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Sample records for airway glucose concentrations

  1. 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

  2. Modeling of relationship between glucose concentration in blood and glucose concentration in interstitial fluid

    NASA Astrophysics Data System (ADS)

    Shi, Ting; Li, Dachao; Ji, Yongjie; Li, Guoqing; Xu, Kexin

    2012-03-01

    In recent years, using the detection of interstitial fluid glucose concentration to realize the real-time continuous monitoring of blood glucose concentration gets more and more attention, because for one person, the relationship between blood glucose concentration and interstitial fluid glucose concentration satisfies specific rules. However, the glucose concentration in interstitial fluid is not entirely equal to the glucose concentration in blood and has a physiological lag because of the physiological difference of cells in blood and interstitial fluid. Because the clinical diagnostic criteria of diabetes are still blood glucose concentration, the evaluation model of the physiological lag parameter between the glucose concentration in blood and the glucose concentration in interstitial fluid should be established. The physiological difference in glucose molecules uptake, utilization, and elimination by cells in blood and interstitial fluid and the diffusion velocity of glucose molecule from blood to interstitial fluid will be induced to the mass transfer model to express the physiological lag parameter. Based on the continuous monitoring of glucose concentration in interstitial fluid, the project had studied the mass transfer model to establish the evaluation model of the physiological lag parameter between the glucose concentration in blood and the glucose concentration in interstitial fluid. We have preliminary achieved to evaluate the physiological lag parameter exactly and predict the glucose concentration in blood through the glucose concentration in interstitial fluid accurately.

  3. Carinal and tubular airway particle concentrations in the large airways of non-smokers in the general population: evidence for high particle concentration at airway carinas.

    PubMed Central

    Churg, A; Vedal, S

    1996-01-01

    OBJECTIVE: To evaluate the extent to which human airway carinas accumulate ambient atmospheric particles, a newly developed technique was used to micro-dissect and analyse particle concentration in tubular segments and carinas of the large airways of 10 necropsy lungs from non-smokers from the general population of Vancouver. METHODS: Ratios of the particle concentrations on the carinas to the tubular segment immediately preceding it were measured with analytical electron microscopy for the mainstem bronchus, upper and lower lobe bronchi, and four different segmental or subsegmental bronchi--that is, Weibel generations 1 to about 5. A total of 119 carinal-tubular pairs was evaluated. RESULTS: Over all cases, both carinal and tubular particle concentrations increased with increasing airway generation; the median ratio of carinal to tubular particle concentration was 9:1 and did not show any trend with airway generation. The ratio was > 5 in 71% of carinal-tubular pairs, > 10 in 42% of pairs, > 20 in 31% of pairs, and > 100 in 9% of pairs. Some subjects showed a notable tendency to high ratios, with many ratios > 100, and other subjects had a tendency toward low ratios. The predominant mineral species in both carinas and tubular airway segments was crystalline silica and the relative proportion was similar in both sites; however, mean particle diameter was consistently less in the carinal tissues. CONCLUSIONS: These findings suggest that the ratio of carinal to tubular retained particles in the large airways in non-smokers is higher than might be supposed from data generated in airway casts, and that there is considerable variation in this ratio between subjects. This finding is of potential interest in models of carcinogen, toxin, and dose of fibrogenic agent to the large airways as it suggests high and sometimes extreme concentrations of toxic particles at carinas, and thus reinforces the notion that carinas may be sites of initiation of disease. PMID:8983467

  4. High glucose induces dysfunction of airway epithelial barrier through down-regulation of connexin 43.

    PubMed

    Yu, Hongmei; Yang, Juan; Zhou, Xiangdong; Xiao, Qian; Lü, Yang; Xia, Li

    2016-03-01

    The airway epithelium is a barrier to the inhaled antigens and pathogens. Connexin 43 (Cx43) has been found to play critical role in maintaining the function of airway epithelial barrier and be involved in the pathogenesis of the diabetic retinal vasculature, diabetes nephropathy and diabetes skin. Hyperglycemia has been shown to be an independent risk factor for respiratory infections. We hypothesize that the down-regulation of Cx43 induced by HG alters the expression of tight junctions (zonula occludens-1 (ZO-1) and occludin) and contributes to dysfunction of airway epithelial barrier, and Cx43 plays a critical role in the process in human airway epithelial cells (16 HBE). We show that high glucose (HG) decreased the expression of ZO-1 and occludin, disassociated interaction between Cx43 and tight junctions, and then increased airway epithelial transepithelial electrical resistance (TER) and permeability by down-regulation of Cx43 in human airway epithelial cells. These observations demonstrate an important role for Cx43 in regulating HG-induced dysfunction of airway epithelial barrier. These findings may bring new insights into the molecular pathogenesis of pulmonary infection related to diabetes mellitus and lead to novel therapeutic intervention for the dysfunction of airway epithelial barrier in chronic inflammatory airway diseases.

  5. 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

  6. 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.

  7. 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

  8. Yeast AMP-activated Protein Kinase Monitors Glucose Concentration Changes and Absolute Glucose Levels*

    PubMed Central

    Bendrioua, Loubna; Smedh, Maria; Almquist, Joachim; Cvijovic, Marija; Jirstrand, Mats; Goksör, Mattias; Adiels, Caroline B.; Hohmann, Stefan

    2014-01-01

    Analysis of the time-dependent behavior of a signaling system can provide insight into its dynamic properties. We employed the nucleocytoplasmic shuttling of the transcriptional repressor Mig1 as readout to characterize Snf1-Mig1 dynamics in single yeast cells. Mig1 binds to promoters of target genes and mediates glucose repression. Mig1 is predominantly located in the nucleus when glucose is abundant. Upon glucose depletion, Mig1 is phosphorylated by the yeast AMP-activated kinase Snf1 and exported into the cytoplasm. We used a three-channel microfluidic device to establish a high degree of control over the glucose concentration exposed to cells. Following regimes of glucose up- and downshifts, we observed a very rapid response reaching a new steady state within less than 1 min, different glucose threshold concentrations depending on glucose up- or downshifts, a graded profile with increased cell-to-cell variation at threshold glucose concentrations, and biphasic behavior with a transient translocation of Mig1 upon the shift from high to intermediate glucose concentrations. Fluorescence loss in photobleaching and fluorescence recovery after photobleaching data demonstrate that Mig1 shuttles constantly between the nucleus and cytoplasm, although with different rates, depending on the presence of glucose. Taken together, our data suggest that the Snf1-Mig1 system has the ability to monitor glucose concentration changes as well as absolute glucose levels. The sensitivity over a wide range of glucose levels and different glucose concentration-dependent response profiles are likely determined by the close integration of signaling with the metabolism and may provide for a highly flexible and fast adaptation to an altered nutritional status. PMID:24627493

  9. Cutpoints for screening blood glucose concentrations in healthy senior cats.

    PubMed

    Reeve-Johnson, Mia K; Rand, Jacquie S; Vankan, Dianne; Anderson, Stephen T; Marshall, Rhett; Morton, John M

    2017-02-01

    Objectives The objectives of this study were to determine the reference interval for screening blood glucose in senior cats, to apply this to a population of obese senior cats, to compare screening and fasting blood glucose, to assess whether screening blood glucose is predicted by breed, body weight, body condition score (BCS), behaviour score, fasting blood glucose and/or recent carbohydrate intake and to assess its robustness to changes in methodology. Methods The study included a total of 120 clinically healthy client-owned cats aged 8 years and older of varying breeds and BCSs. Blood glucose was measured at the beginning of the consultation from an ear/paw sample using a portable glucose meter calibrated for cats, and again after physical examination from a jugular sample. Fasting blood glucose was measured after overnight hospitalisation and fasting for 18-24 h. Results The reference interval upper limit for screening blood glucose was 189 mg/dl (10.5 mmol/l). Mean screening blood glucose was greater than mean fasting glucose. Breed, body weight, BCS, behaviour score, fasting blood glucose concentration and amount of carbohydrate consumed 2-24 h before sampling collectively explained only a small proportion of the variability in screening blood glucose. Conclusions and relevance Screening blood glucose measurement represents a simple test, and cats with values from 117-189 mg/dl (6.5-10.5 mmol/l) should be retested several hours later. Cats with initial screening blood glucose >189 mg/dl (10.5 mmol/l), or a second screening blood glucose >116 mg/dl (6.4 mmol/l) several hours after the first, should have fasting glucose and glucose tolerance measured after overnight hospitalisation.

  10. The osmolyte xylitol reduces the salt concentration of airway surface liquid and may enhance bacterial killing

    NASA Astrophysics Data System (ADS)

    Zabner, Joseph; Seiler, Michael P.; Launspach, Janice L.; Karp, Philip H.; Kearney, William R.; Look, Dwight C.; Smith, Jeffrey J.; Welsh, Michael J.

    2000-10-01

    The thin layer of airway surface liquid (ASL) contains antimicrobial substances that kill the small numbers of bacteria that are constantly being deposited in the lungs. An increase in ASL salt concentration inhibits the activity of airway antimicrobial factors and may partially explain the pathogenesis of cystic fibrosis (CF). We tested the hypothesis that an osmolyte with a low transepithelial permeability may lower the ASL salt concentration, thereby enhancing innate immunity. We found that the five-carbon sugar xylitol has a low transepithelial permeability, is poorly metabolized by several bacteria, and can lower the ASL salt concentration in both CF and non-CF airway epithelia in vitro. Furthermore, in a double-blind, randomized, crossover study, xylitol sprayed for 4 days into each nostril of normal volunteers significantly decreased the number of nasal coagulase-negative Staphylococcus compared with saline control. Xylitol may be of value in decreasing ASL salt concentration and enhancing the innate antimicrobial defense at the airway surface.

  11. Effect of different glucose concentrations on proteome of Saccharomyces cerevisiae.

    PubMed

    Guidi, Francesca; Francesca, Guidi; Magherini, Francesca; Francesca, Magherini; Gamberi, Tania; Tania, Gamberi; Borro, Marina; Marina, Borro; Simmaco, Maurizio; Maurizio, Simmaco; Modesti, Alessandra; Alessandra, Modesti

    2010-07-01

    We performed a proteomic study to understand how Saccharomyces cerevisiae adapts its metabolism during the exponential growth on three different concentrations of glucose; this information will be necessary to understand yeast carbon metabolism in different environments. We induced a natural diauxic shift by growing yeast cells in glucose restriction thus having a fast and complete glucose exhaustion. We noticed differential expressions of groups of proteins. Cells in high glucose have a decreased growth rate during the initial phase of fermentation; in glucose restriction and in high glucose we found an over-expression of a protein (Peroxiredoxin) involved in protection against oxidative stress insult. The information obtained in our study validates the application of a proteomic approach for the identification of the molecular bases of environmental variations such as fermentation in high glucose and during a naturally induced diauxic shift.

  12. 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.

  13. Concentration of the antibacterial precursor thiocyanate in cystic fibrosis airway secretions

    PubMed Central

    Lorentzen, Daniel; Durairaj, Lakshmi; Pezzulo, Alejandro A.; Nakano, Yoko; Launspach, Janice; Stoltz, David A.; Zamba, Gideon; McCray, Paul B.; Zabner, Joseph; Welsh, Michael J.; Nauseef, William M.; Bánfi, Botond

    2011-01-01

    A recently discovered enzyme system produces antibacterial hypothiocyanite (OSCN−) in the airway lumen by oxidizing the secreted precursor thiocyanate (SCN−). Airway epithelial cultures have been shown to secrete SCN− in a CFTR-dependent manner. Thus, reduced SCN− availability in the airway might contribute to the pathogenesis of cystic fibrosis (CF), a disease caused by mutations in the CFTR gene and characterized by an airway host defense defect. We tested this hypothesis by analyzing the SCN− concentration in the nasal airway surface liquid (ASL) of CF patients and non-CF subjects, and in the tracheobronchial ASL of CFTR-ΔF508 homozygous pigs and control littermates. In the nasal ASL, the SCN− concentration was ~30-fold higher than in serum independently of the CFTR mutation status of the human subject. In the tracheobronchial ASL of CF pigs, the SCN− concentration was somewhat reduced. Among human subjects, SCN− concentrations in the ASL varied from person to person independent of CFTR expression, and CF patients with high SCN− levels had better lung function than those with low SCN− levels. Thus, although CFTR can contribute to SCN− transport, it is not indispensable for the high SCN− concentration in ASL. The correlation between lung function and SCN− concentration in CF patients may reflect a beneficial role for SCN−. PMID:21334431

  14. Optoacoustic signal profiles for monitoring glucose concentration in turbid media

    NASA Astrophysics Data System (ADS)

    Larin, Kirill V.; Oraevsky, Alexander A.

    1999-03-01

    Our research project is focused on theoretical and experimental studies into the possibility of in vivo monitoring of blood glucose concentration. Previous experiments demonstrated that the presence of glucose dissolved in aqueous solution of polystyrene microspheres increases the refractive index of this solution due to glucose hydrophilic properties. As a strong osmolyte glucose influences the scattering properties of any particles or fibers suspended in water or biological fluids. We measured profiles of absorbed laser energy distributions as a function of glucose concentration in aqueous solution of polystyrene microspheres colored with potassium chromate. Experiments were performed at the wavelength of the Nd:YAG laser third harmonic, (lambda) equals 355 nm. The results obtained demonstrated a 4.5% decrease in effective optical attenuation coefficient with a 100 mM increase in glucose concentration. These initial results demonstrated that the effect of glucose on optical attenuation of turbid aqueous solutions is small but reliably measurable with the use of the time-resolved optoacoustic technique.

  15. Determination of glucose concentration using Fourier domain optical coherence tomogram

    NASA Astrophysics Data System (ADS)

    El-Sharkawy, Yasser H.

    2009-02-01

    In order to enhance cell culture growth in biosensors such as those for glucose detection must be developed that are capable of monitoring cell culture processes continuously and accurate. Fourier domain optical coherence tomography (FD-OCT) is used to obtain cell images with nanometer level resolution by analyzing the interference pattern by the mixing of reference and objective light to determine glucose concentration in doped double distilled water and create a glucose signature spectrum in salt-sugar solution. We demonstrate ultrahigh-resolution optical coherence tomography (OCT) imaging of in vitro biological cells and an improved deflection angle measurements formal and back projection method is used to reconstruct the two-dimensional glucose concentration performs refractive index distribution. Slopes of OCT signals decreased substantially and almost linearly with the increase of glucose concentration from 2.5 to 15 mg/dl. Phantom studies demonstrated 1% accuracy of scattering- coefficient measurement. Our theoretical and experimental studies suggest that glucose concentration can potentially be measured non-invasively with high sensitivity and accuracy with OCT systems.

  16. 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

  17. IR spectroscopy vs. Raman scattering by measurement of glucose concentration

    NASA Astrophysics Data System (ADS)

    Abdallah, O.; Hansmann, J.; Bolz, A.; Mertsching, H.

    2010-11-01

    By developing a non-invasive device for glucose concentration measurement, two promising methods were compared for that aim. The Raman scattering using Laser at the wavelength 785 nm and the light scattering in R- and IR-range are demonstrated. An easy accessible and low-cost method for glucose concentration monitoring and management to avoid its complications will be a great help for diabetic patients. Raman Scattering is a promising method for noninvasively measuring of glucose and for the diagnostic of pathological tissue variations. Despite the power and the time of measurement can be reduced using enhanced Raman scattering, it will be difficult to develop a compatible device with low power Laser and low price for a non-invasive method for home monitoring. As using IR-spectroscopy at wavelengths slightly below 10000 nm, the absorption of glucose can be well discriminated from that of water, LED`s or LD's at these wavelengths are very expensive for this purpose. At wavelengths about 6250 and 7700 glucose has a less light absorption than water. Also slightly above 3000 nm glucose has a high absorption. There are also possibilities for the measurement in the NIR at wavelengths between 1400 nm and 1670 nm. Scattering measurements at wavelengths below 900 nm and our measurements with the wavelength about 640 nm give reproducible glucose dependence on the reflected light from a glucose solution at a constant temperature. A multi-sensor with different wavelengths and temperature sensor will be a good choice for in-vivo glucose monitoring.

  18. Effects of concentrated ambient particles on normal and hypersecretory airways in rats.

    PubMed

    Harkema, Jack R; Keeler, Gerald; Wagner, James; Morishita, Masako; Timm, Edward; Hotchkiss, Jon; Marsik, Frank; Dvonch, Timothy; Kaminski, Norbert; Barr, Edward

    2004-08-01

    in southwestern Detroit during the summer months when particulate air pollution is usually high (July and September 2000). We monitored the outdoor air pollution in this community daily, and exposed normal and compromised rats to concentrated PM2.5 from this local urban atmosphere. Rats in the inhalation studies were exposed for 1 day or for 4 or 5 consecutive days (10 hours/day) to either filtered air (controls) or concentrated ambient particles (CAPs) delivered by a Harvard ambient fine particle concentrator. Rats were killed 24 hours after the end of the exposure. Biochemical, morphometric, and molecular techniques were used to identify airway epithelial and inflammatory responses to CAPs. Lung lobes were also either intratracheally lavaged with saline to determine cellular composition and protein in bronchoalveolar lavage fluid (BALF) or removed for analysis by inductively coupled plasma-mass spectrometry (ICPMS) to detect retention of ambient PM2.5--derived trace elements. The Harvard concentrator effectively concentrated the fine ambient particles from this urban atmosphere (10-30 times) without significantly changing the major physicochemical features of the atmospheric particles. Daily CAPs mass concentrations during the 10-hour exposure period (0800-1800) in July ranged from 16 to 895 microg/m3 and in September ranged from 81 to 755 microg/m3. In general, chemical characteristics of ambient particles were conserved through the concentrator into the exposure chamber. Single or repeated exposures to CAPs did not cause adverse effects in the nasal or pulmonary airways of healthy F344 or BN rats. In addition, CAPs-related toxicity was not observed in F344 rats pretreated with bacterial endotoxin. Variable airway responses to CAPs exposure were observed in BN rats with preexisting allergic airway disease induced by OVA sensitization and challenge. Only OVA-challenged BN rats exposed to CAPs for 5 consecutive days in September 2000 had significant increases in

  19. Effect of levofloxacin on serum glucose concentration in rats.

    PubMed

    Ishiwata, Yasuyoshi; Itoga, Yoshie; Yasuhara, Masato

    2006-12-03

    To clarify the mechanism of fluoroquinolone-induced abnormalities in blood glucose, the effect of levofloxacin on serum glucose concentration was investigated in rats. Rats received an intravenous injection of levofloxacin and their arterial blood was sampled periodically. The serum glucose concentration decreased after an injection of 100 mg/kg of levofloxacin, while it increased at levofloxacin 300 mg/kg. The serum immunoreactive insulin concentration increased as the dose of levofloxacin increased. The serum epinephrine concentration was rapidly elevated by levofloxacin at 300 mg/kg. The serum histamine concentration increased after injections of levofloxacin, 200 and 300 mg/kg. Diphenhydramine (1 mg/kg) antagonized the hyperglycemia induced by 300 mg/kg of levofloxacin. In an in vitro study, the release of epinephrine from the adrenal medulla in the presence of levofloxacin was determined. Levofloxacin (300 microg/ml) did not affect epinephrine release from the adrenal medulla. Levofloxacin can induce hypoglycemia and hyperglycemia in rats. Levofloxacin can promote histamine release, leading to an increased serum epinephrine concentration and hyperglycemia.

  20. 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.

  1. Diagnostic significance of nitric oxide concentrations in exhaled air from the airways in allergic rhinitis patients

    PubMed Central

    Krzych-Fałta, Edyta; Samoliński, Bolesław K; Zalewska, Marta

    2016-01-01

    Introduction The effect of nitric oxide (NO) on the human body is very important due its physiological regulation of the following functions of airways: modulation of ciliary movement and maintenance of sterility in sinuses. Aim To evaluate the diagnostic significance of NO concentrations in exhaled air from the upper and lower airways in patients diagnosed with allergic rhinitis (AR). Material and methods The subjects included in the study were a group of 30 people diagnosed with sensitivity to environmental allergens and a control group consisting of 30 healthy subjects. The measurement of NO in the air exhaled from the lower and upper airways was performed using an on-line method by means of Restricted Exhaled Breath (REB), as well as using the measurement procedure (chemiluminescence) set out in the guidelines prepared in 2005 by the American Thoracic Society and the European Respiratory Society. Results In the late phase of the allergic reaction, higher values of the level of exhaled NO concentration from the lower airways were observed in the groups of subjects up to the threshold values of 25.17 ppb in the group of subjects with year-round allergic rhinitis and 21.78 ppb in the group with diagnosed seasonal allergic rhinitis. The difference in the concentration of NO exhaled from the lungs between the test group and the control group in the 4th h of the test was statistically significant (p = 0.045). Conclusions Exhaled NO should be considered as a marker of airway inflammation. It plays an important role in the differential diagnosis of allergy. PMID:27279816

  2. 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

  3. 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.

  4. 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.

  5. Increased phosphatidylcholine concentration in saliva reduces surface tension and improves airway patency in obstructive sleep apnoea.

    PubMed

    Kawai, M; Kirkness, J P; Yamamura, S; Imaizumi, K; Yoshimine, H; Oi, K; Ayuse, T

    2013-10-01

    Surface tension may have important role for maintaining upper airway patency in patients with obstructive sleep apnoea. It has been demonstrated that elevated surface tension increases the pharyngeal pressures required to reopen the upper airway following collapse. The aim of the study was to evaluate the associations between the concentrations of endogenous surfactants in saliva with indices of upper airway patency in obstructive sleep apnoea. We studied 20 male patients with obstructive sleep apnoea (age: 60·3 ± 10·3 years; BMI: 25·9 ± 4·6 kg m(-2); AHI: 41·5 ± 18·6 events h(-1)). We obtained 100-μL samples of saliva prior to overnight polysomnographic sleep study. The surface tension was determined using the pull-off force technique. The concentration of phosphatidylcholine (PC) was evaluated by liquid chromatography-mass spectrometry (LC-MS/MS). Regression analysis between apnoea, hypopnoea and apnoea/hypopnoea indices and the ratio of hypopnoea time/total disordered breathing time (HT/DBT) with surface tension and PC were performed. P < 0·05 was considered significant. The mean saliva surface tension was 48·8 ± 8·0 mN m(-1) and PC concentration was 15·7 ± 11·1 nM. The surface tension was negatively correlated with the PC concentration (r = -0·48, P = 0·03). There was a significant positive correlation between surface tension with hypopnoea index (r = 0·50, P = 0·03) and HT/DBT (r = 0·6, P = 0·006), but not apnoea or apnoea/hypopnoea index (P > 0·11). Similarly, PC concentration negatively correlated with hypopnoea index (r = -0·45, P = 0·04) and HT/DBT (r = -0·6, P = 0·004), but not with apnoea index or AHI (P > 0·08). An increase in salivary PC concentration may increase upper airway patency in obstructive sleep apnoea through a reduction in surface tension.

  6. Measurement of glucose concentration in interstitial fluid by surface plasmon resonance with D-galactose/D-glucose binding protein

    NASA Astrophysics Data System (ADS)

    Li, D. C.; Zhang, J. X.; Wu, P.; Huang, F. X.; Song, B.; Xu, K. X.

    2009-08-01

    A novel minimally invasive way to measure blood glucose concentration is proposed by combining interstitial fluid transdermal extraction and surface plasma resonance (SPR) detecting. 55K Hz low-frequency ultrasound pulse is applied for less than 30 seconds to enhance the skin permeability and then interstitial fluid is extracted out of skin by vacuum. The mathematical model to express the correlation between interstitial fluid glucose and blood glucose is also developed by considering the changes of the skin conductivity. The glucose concentration in the interstitial fluid is determined using an optical SPR biological sensor that measures the refractive index. A protein-glucose binding technology using Dgalactose/ D-glucose Binding Protein for specific absorption of glucose is employed to increase SPR measurement precision. By immobilizing GGBP onto the surface of the SPR sensor, the experimental result indicates the detecting resolution of glucose rises to 1mg/L, the system succeeds in distinguishing glucose from other components in mixture. The feasibility of this method is validated for clinical application with the requirements of bloodless, painless, continuous glucose monitoring and a prototype microfluidic diabetes-monitoring device is under development.

  7. A study on detection of glucose concentration using changes in color coordinates.

    PubMed

    Kim, Ji-Sun; Oh, Han-Byeol; Kim, A-Hee; Kim, Jun-Sik; Lee, Eun-Suk; Baek, Jin-Young; Lee, Ki Sung; Chung, Soon-Cheol; Jun, Jae-Hoon

    2017-01-02

    Glucose concentration is closely related to the metabolic activity of cells and it is the most important substance as the energy source of a living body which plays an important role in the human body. This paper proposes an optical method that can measure the concentration of glucose. The change in glucose concentration was observed by using CIE diagram, and wavelength and purity values were detected. Also, even small changes in glucose concentration can be evaluated through mathematical modeling. This system is simple, economical, and capable of quantifying optical signals with numerical values for glucose sensing. This method can be applicable to the clinical field that examines diabetes mellitus or metabolic syndrome.

  8. Development of a fluorescent method for simultaneous measurement of glucose concentrations in interstitial fluid and blood

    NASA Astrophysics Data System (ADS)

    Shi, Ting; Li, Dachao; Li, Guoqing; Chen, Limin; Lin, Yuan; Xu, Kexin; Lu, Luo

    2013-12-01

    Continuous blood glucose monitoring is of great clinical significance to patients with diabetes. One of the effective methods to monitor blood glucose is to measure glucose concentrations of interstitial fluid (ISF). However, a time-delay problem exists between ISF and blood glucose concentrations, which results in difficulty in indicating real-time blood glucose concentrations. Therefore, we developed a fluorescent method to verify the accuracy and reliability of simultaneous ISF and blood glucose measurement, especially incorporating it into research on the delay relationship between blood and ISF glucose changes. This method is based on a competitive reaction among borate polymer, alizarin and glucose. When glucose molecules combine with borate polymers in alizarin-borate polymer competitively, changes in fluorescence intensity demonstrate changes in glucose concentrations. By applying the measured results to the blood and ISF glucose delay relationship, we were able to calculate the time delay as an average of 2.16 ± 2.05 min for ISF glucose changes with reference to blood glucose concentrations.

  9. The Importance of Different Frequency Bands in Predicting Subcutaneous Glucose Concentration in Type 1 Diabetic Patients

    DTIC Science & Technology

    2010-02-01

    Maran, A. Facchinetti, and C. Cobelli, ―Glucose concentration can be predicted ahead in time from continuous glucose monitoring sensor time-series...Polonsky, ―Circadian modulation of glucose and insulin responses to meals: relationship to cortisol rhythm,‖ Am. J. Physiol. Endocrinol. Metab., vol

  10. 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.

  11. Fetal glucose uptake and utilization as functions of maternal glucose concentration.

    PubMed

    Hay, W W; Sparks, J W; Wilkening, R B; Battaglia, F C; Meschia, G

    1984-03-01

    Seventeen studies were performed in 12 pregnant sheep to examine the relationship among simultaneously measured glucose uptake via the umbilical circulation, fetal glucose utilization (mg X min-1 X kg-1), and maternal arterial glucose (Gm, mg/dl). Fetal glucose utilization was measured by means of tracer glucose infused into the fetus or both mother and fetus. By fasting the ewe, Gm was varied in the 62-22 range. A decrease in Gm was accompanied by a significant (P less than 0.001) decrease in umbilical uptake (uptake = 0.09 Gm - 0.96, r = 0.82) and in fetal utilization, measured either by [U-14C]glucose (utilization = 0.062 Gm + 0.91, r = 0.90) or [6-3H]glucose (utilization = 0.065 Gm + 0.51, r = 0.91). At uptake greater than 3 mg X min-1 X kg-1, utilization and uptake were not significantly different. At lower uptakes, utilization did not decline as much as uptake. The results demonstrate that maternal fasting decreases both the umbilical uptake and the fetal utilization of glucose and suggest that fetal glucogenesis increases when the availability of exogenous glucose is markedly reduced.

  12. IN VITRO EFFECTS OF PARTICULATE MATTER ON AIRWAY EPITHELIAL CELLS ISOLATED FROM CONCENTRATED AIR PARTICLES-EXPOSED SPONTANEOUS HYPERTENSIVE RATS

    EPA Science Inventory

    In vitro effects of particulate matter on airway epithelial cells isolated from concentrated air particles-exposed spontaneous hypertensive rats

    Ines Pagan, Urmila Kodavanti, Paul Evansky, Daniel L Costa and Janice A Dye. U.S. Environmental Protection Agency, ORD, National...

  13. Acid and organic aerosol coatings on magnetic nanoparticles increase iron concentrations in human airway epithelial cells.

    PubMed

    Ghio, Andrew J; Dailey, Lisa A; Richards, Judy H; Jang, Myoseon

    2009-07-01

    Numerous industrial applications for man-made nanoparticles have been proposed. Interactions of nanoparticles with agents in the atmosphere may impact human health. We tested the postulate that in vitro exposures of respiratory epithelial cells to airborne magnetic nanoparticles (MNP; Fe(3)O(4)) with and without a secondary organic aerosol (SOA) and an inorganic acid could affect iron homeostasis, oxidative stress, and interleukin (IL)-8 release. Cell iron concentrations were increased after exposures to MNP and values were further elevated with co-exposures to either SOA or inorganic acid. Increased expression of ferritin and elevated levels of RNA for DMT1, proteins for iron storage and transport respectively, followed MNP exposures, but values were significant for only those with co-exposures to inorganic acid and organic aerosols. Cell iron concentration corresponded to a measure of oxidative stress in the airway epithelial cells; MNP with co-exposures to SOA and inorganic acid increased both available metal and indices of oxidant generation. Finally, the release of a proinflammatory cytokine (i.e. IL-8) by the exposed cells similarly increased with cell iron concentration. We conclude that MNP can interact with a SOA and an inorganic acid to present metal in a catalytically reactive state to cultured respiratory cells. This produces an oxidative stress to affect a release of IL-8.

  14. Effects of concentrated ambient particles and diesel engine exhaust on allergic airway disease in Brown Norway rats.

    PubMed

    Harkema, Jack R; Wagner, James G; Kaminski, Norbert E; Morishita, Masako; Keeler, Gerald J; McDonald, Jacob D; Barrett, Edward G

    2009-11-01

    Increased concentrations of airborne fine particulate matter (PM2.5; particulate matter with an aerodynamic diameter < or = 2.5 microm) are associated with increases in emergency room visits and hospitalizations of asthmatic patients. Emissions from local stationary combustion sources (e.g., coal-burning power plants) or mobile motor vehicles (e.g., diesel-powered trucks) have been identified as potential contributors to the development or exacerbation of allergic airway disease. In the present study, a rodent model of allergic airway disease was used to study the effects of concentrated ambient particles (CAPs) or diesel engine exhaust (DEE) on the development of allergic airway disease in rats sensitized to the allergen ovalbumin (OVA). The overall objective of our project was to understand the effects of PM2.5 on the development of OVA-induced allergic airway disease. Our specific aims were to test the following hypotheses: (1) exposure to CAPs during OVA challenge enhances epithelial remodeling of the airway and inflammation in rats previously sensitized to the allergen; and (2) exposure to DEE during OVA sensitization, or during OVA challenge, exacerbates epithelial remodeling of the airway and inflammation in rats. In the DEE studies, Brown Norway (BN) rats were sensitized with three daily intranasal (IN) instillations of 0.5% OVA, and then two weeks later were challenged with IN OVA or saline for 3 consecutive days. Rats were exposed to DEE diluted to mass concentrations of 30 or 300 microg/m3 diesel exhaust particles (DEPs) or to filtered air during either the sensitization or challenge periods. For the CAPs studies, the same OVA sensitization and challenge rat model was used but exposures to Detroit, Michigan, CAPs were limited to the OVA challenge period. Two separate 3-day CAPs exposures were conducted (week 1, high mean mass concentration = 595 microg/m3; week 2, low mean mass concentration = 356 microg/m3) during OVA challenge. In both the DEE and CAPs

  15. Application of transcutaneous diffuse reflectance spectroscopy in the measurement of blood glucose concentration

    NASA Astrophysics Data System (ADS)

    Chen, Wenliang; Liu, Rong; Cui, Houxin; Xu, Kexin; Lv, Lina

    2004-07-01

    In this paper, the propagation characteristics of near-infrared (NIR) light in the palm tissue are analyzed, and the principle and feasibility of using transcutaneous diffuse reflectance spectroscopy for non-invasive blood glucose detection are presented. An optical probe suitable for measuring the diffuse reflectance spectrum of human palm and a non-invasive blood glucose detection system using NIR spectroscopy are designed. Based on this system, oral glucose tolerance tests are performed to measure the blood glucose concentrations of two young healthy volunteers. The partial least square calibration model is then constructed by all individual experimental data. The final result shows that correlation coefficients of the two experiments between the predicted blood glucose concentrations and the reference blood glucose concentrations are 0.9870 and 0.9854, respectively. The root mean square errors of prediction of full cross validation are 0.54 and 0.52 mmol/l, respectively.

  16. High concentrations of glucose reduce the oxidative metabolism of dog neutrophils in vitro

    PubMed Central

    2013-01-01

    Background Dogs are commonly affected by hyperglycemic conditions. Hyperglycemia compromises the immune response and favors bacterial infections; however, reports on the effects of glucose on neutrophil oxidative metabolism and apoptosis are conflicting in humans and rare in dogs. Considering the many complex factors that affect neutrophil oxidative metabolism in vivo, we investigated in vitro the specific effect of high concentrations of glucose on superoxide production and apoptosis rate in neutrophils from healthy dogs. Results The capacity of the neutrophils to reduce tetrazolium nitroblue decreased significantly in the higher concentration of glucose (15.13 ± 9.73% (8 mmol/L) versus 8.93 ± 5.71% (16 mmol/L)). However, there were no changes in tetrazolium nitroblue reduction at different glucose concentrations when the neutrophils were first activated with phorbol myristate acetate. High concentrations of glucose did not affect the viability and apoptosis rate of canine neutrophils either with or without prior camptothecin stimulation. This study provides the first evidence that high concentrations of glucose inhibit the oxidative metabolism of canine neutrophils in vitro in a manner similar to that which occurs in humans, and that the decrease in superoxide production did not increase the apoptosis rate. Conclusions A high concentration of glucose reduces the oxidative metabolism of canine neutrophils in vitro. It is likely that glucose at high concentrations rapidly affects membrane receptors responsible for the activation of NADPH oxidase in neutrophils; therefore, the nonspecific immune response can be compromised in dogs with acute and chronic hyperglycemic conditions. PMID:23388121

  17. 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.

  18. Glucose uptake and transport in contracting, perfused rat muscle with different pre-contraction glycogen concentrations.

    PubMed Central

    Hespel, P; Richter, E A

    1990-01-01

    1. Glucose uptake and transport, muscle glycogen, free glucose and glucose-6-phosphate concentrations were studied in perfused resting and contracting rat skeletal muscle with different pre-contraction glycogen concentrations. Rats were pre-conditioned by a combination of swimming exercise and diet, resulting in either low (glycogen-depleted rats), normal (control rats) or high (supercompensated rats) muscle glycogen concentrations at the time their hindlimbs were perfused. 2. Compared with control rats, pre-contraction muscle glycogen concentration was approximately 40% lower in glycogen-depleted rats, whereas it was 40% higher in supercompensated rats. Muscle glycogen break-down correlated positively (r = 0.76; P less than 0.001) with pre-contraction muscle glycogen concentration. 3. Glucose uptake during contractions was approximately 50% higher in glycogen-depleted hindquarters than in control hindquarters; in supercompensated hindquarters it was 30% lower. When rats with similar muscle glycogen concentrations were compared, glucose uptake in hindquarters from rats that had exercised on the preceding day was approximately 20% higher than in hindquarters from rats that had not exercised on the preceding day. 4. Muscle membrane glucose transport, as measured by the rate of accumulation of 14C-3-O-methylglucose in the contracting muscles, was 25% lower in supercompensated than in glycogen-depleted muscles at the onset as well as at the end of the 15 min contraction period. 5. Intracellular concentrations of free glucose and glucose-6-phosphate were higher at rest and during the entire 15-min stimulation period in supercompensated muscles than in glycogen-depleted muscles, and glucose uptake during contractions correlated negatively with free glucose (r = -0.52; P less than 0.01) as well as with glucose-6-phosphate (r = -0.49; P less than 0.01) concentrations. 6. It is concluded that: (a) The rate of glucose uptake in contracting skeletal muscle is dependent on the

  19. Highly sensitive detection of glucose concentration with opto-fluidics ring resonator

    NASA Astrophysics Data System (ADS)

    Luo, Yunhan; Khaing Oo, Maung Kyaw; Ge, Jia; Chen, Zhe; Fan, Xudong

    2012-06-01

    Noninvasive detection of glucose has been heavily researched in their roles of offering cost-effective, painless, and bloodless monitoring of glucose concentration. In this work, we describe a novel, label-free, and sensitive approach for detecting the glucose concentration in human interstitial fluid samples using the opto-fluidic ring resonator (OFRR). The OFRR incorporates microfluidics and optical ring resonator sensing technology to achieve rapid label-free detection in a small and low-cost platform. In this study, bulk refractive index measurements are presented. Results show that the OFRR is able to detect glucose at medically relevant concentrations in interstitial fluid ranging from 0 to 25 mM, with a detection limit of 0.32 mM, which is lower than clinical requirement by one order of magnitude. Our work is believed to lead to a device that can be used to frequently monitor glucose concentration in a low-cost and painless manner.

  20. Photonic crystal based biosensor for the detection of glucose concentration in urine

    NASA Astrophysics Data System (ADS)

    Robinson, Savarimuthu; Dhanlaksmi, Nagaraj

    2017-03-01

    Photonic sensing technology is a new and accurate measurement technology for bio-sensing applications. In this paper, a two-dimensional photonic crystal ring resonator based sensor is proposed and designed to detect the glucose concentration in urine over the range of 0 gm/dl-15 gm/dl. The proposed sensor is consisted of two inverted "L" waveguides and a ring resonator. If the glucose concentration in urine is varied, the refractive index of the urine is varied, which in turn the output response of sensor will be varied. By having the aforementioned principle, the glucose concentration in urine, glucose concentration in blood, albumin, urea, and bilirubin concentration in urine are predicted. The size of the proposed sensor is about 11.4 µm×11.4 µm, and the sensor can predict the result very accurately without any delay, hence, this attempt could be implemented for medical applications.

  1. Photonic crystal based biosensor for the detection of glucose concentration in urine

    NASA Astrophysics Data System (ADS)

    Robinson, Savarimuthu; Dhanlaksmi, Nagaraj

    2016-10-01

    Photonic sensing technology is a new and accurate measurement technology for bio-sensing applications. In this paper, a two-dimensional photonic crystal ring resonator based sensor is proposed and designed to detect the glucose concentration in urine over the range of 0 gm/dl-15 gm/dl. The proposed sensor is consisted of two inverted "L" waveguides and a ring resonator. If the glucose concentration in urine is varied, the refractive index of the urine is varied, which in turn the output response of sensor will be varied. By having the aforementioned principle, the glucose concentration in urine, glucose concentration in blood, albumin, urea, and bilirubin concentration in urine are predicted. The size of the proposed sensor is about 11.4 µm×11.4 µm, and the sensor can predict the result very accurately without any delay, hence, this attempt could be implemented for medical applications.

  2. Predicting Human Subcutaneous Glucose Concentration in Real Time: A Universal Data-Driven Approach

    DTIC Science & Technology

    2011-09-01

    devices provide a minimally invasive mechanism for monitoring the glycemic state of a patient as frequently as every minute. However, the ability of...glucose concentration may already be at an unacceptably high or low level) rather than alerting the patients of an impending glucose excursion so

  3. 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

  4. 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

  5. Analysis of Blood Glucose Concentration by Interstitial Fluid Extracted in a Minimally Invasive way

    NASA Astrophysics Data System (ADS)

    Hu, Xiaotang; Xu, Kexin; Cao, Xuejun; Qu, Xinghua; Li, Dachao

    2009-08-01

    A novel minimally invasive way to measure blood glucose concentration is proposed by combining interstitial fluid (ISF) transdermal extraction and surface plasmon resonance (SPR) detection. 55 kHz low-frequency ultrasound pulses are applied for 30 seconds to enhance the skin permeability and then interstitial fluid is extracted out of skin by vacuum. The glucose concentration in the interstitial fluid is determined using an optical SPR sensor that measures the refractive index. A protein-glucose binding technology using D-galactose/D-glucose Binding Protein for specific absorption of glucose is also employed to increase SPR measurement precision. The mathematical model to express the correlation between interstitial fluid glucose and blood glucose is also developed by considering the changes of the skin conductivity. The feasibility of this method is validated for clinical application with the requirements of bloodless, painless, continuous glucose monitoring and a prototype microfluidic diabetes-monitoring device is under development with a current glucose resolution of approximately 1 mg/l.

  6. 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.

  7. Effect of different ozone concentrations on the neurogenic contraction and relaxation of guinea pig airways.

    PubMed

    Sommer, B; Vargas, M H; Segura, P; Bazán-Perkins, B; Carbajal, V; Chávez, J; Gustin, P; Montaño, L M

    1997-01-01

    Prejunctional and postjunctional effects of several ozone (O3) concentrations, including those found in highly polluted cities, were evaluated in guinea pig airways. Animals bred in O3-free conditions were exposed to air or O3 (0.3, 0.6 or 1.2 ppm) during 4 h, and studied 16-18 h later. Tracheal and bronchial rings were studied in organ baths. Electrical field stimulation (EFS) (100 V, 2 ms, 10 s) was given at increasing frequencies (0.25-16 Hz). Some tissues received atropine (2 microM) and/or propranolol (10 microM). Concentration-response curves to carbachol, isoproterenol, nitroprusside, and substance P were constructed. In tracheas, almost all O3 concentrations decreased the relaxation at low EFS frequencies, but had no effect on the propranolol-resistant (i-NANC) relaxation, suggesting that only adrenergic relaxation was affected. This was a prejunctional effect, since O3 did not modify the responses to isoproterenol. Relaxation induced by a nitric oxide (NO) donor, nitroprusside, was not affected by O3, which agrees with the lack of O3-effect on i-NANC system. O3 did not modify the EFS-induced e-NANC contraction in atropine-treated bronchi, nor the contraction caused by exogenous substance P. By contrast, in bronchi without atropine, 1.2 ppm O3 increased the e-NANC contraction induced by the highest EFS (16 Hz). O3 increased the maximum responses to carbachol in tracheas (1.2 ppm) and bronchi (0.6 and 1.2 ppm). In conclusion, we found that: a) O3 decreased adrenergic relaxation in guinea pig tracheas at low EFS frequencies through a prejunctional alteration; b) O3 did not modify the i-NANC relaxation in tracheas, at least the NO-mediated; c) O3 added a cholinergic component to the bronchial slow-phase (e-NANC) contraction evoked by EFS; and d) O3 enhanced the cholinergic responses in trachea and bronchi by a postjunctional mechanism.

  8. 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

  9. Effect of ground cinnamon on postprandial blood glucose concentration in normal-weight and obese adults.

    PubMed

    Magistrelli, Ashley; Chezem, Jo Carol

    2012-11-01

    In healthy normal-weight adults, cinnamon reduces blood glucose concentration and enhances insulin sensitivity. Insulin resistance, resulting in increased fasting and postprandial blood glucose and insulin levels, is commonly observed in obese individuals. The objective of the study was to compare declines in postprandial glycemic response in normal-weight and obese subjects with ingestion of 6 g ground cinnamon. In a crossover study, subjects consumed 50 g available carbohydrate in instant farina cereal, served plain or with 6 g ground cinnamon. Blood glucose concentration, the main outcome measure, was assessed at minutes 0, 15, 30, 45, 60, 90, and 120. Repeated-measures analysis of variance evaluated the effects of body mass index (BMI) group, dietary condition, and time on blood glucose. Paired t-test assessed blood glucose at individual time points and glucose area under the curve (AUC) between dietary conditions. Thirty subjects between the ages of 18 and 30 years, 15 with BMIs between 18.5 and 24.9 and 15 with BMIs of 30.0 or more, completed the study. There was no significant difference in blood glucose between the two BMI groups at any time point. However, in a combined analysis of all subjects, the addition of cinnamon to the cereal significantly reduced 120-minute glucose AUC (P=0.008) and blood glucose at 15 (P=0.001), 30 (P<0.001), 45 (P<0.001), and 60 (P=0.001) minutes. At 120 minutes, blood glucose was significantly higher with cinnamon consumption (P<0.001). These results suggest cinnamon may be effective in moderating postprandial glucose response in normal weight and obese adults.

  10. 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.

  11. Jump neural network for real-time prediction of glucose concentration.

    PubMed

    Zecchin, Chiara; Facchinetti, Andrea; Sparacino, Giovanni; Cobelli, Claudio

    2015-01-01

    Prediction of the future value of a variable is of central importance in a wide variety of fields, including economy and finance, meteorology, informatics, and, last but not least important, medicine. For example, in the therapy of Type 1 Diabetes (T1D), in which, for patient safety, glucose concentration in the blood should be maintained in a defined normoglycemic range, the ability to forecast glucose concentration in the short-term (with a prediction horizon of around 30 min) might be sufficient to reduce the incidence of hypoglycemic and hyperglycemic events. Neural Network (NN) approaches are suitable for prediction purposes because of their ability to model nonlinear dynamics and handle in their inputs signals coming from different domains. In this chapter we illustrate the design of a jump NN glucose prediction algorithm that exploits past glucose concentration data, measured in real-time by a minimally invasive continuous glucose monitoring (CGM) sensor, and information on ingested carbohydrates, supplied by the patient himself or herself. The methodology is assessed by tuning the NN on data of ten T1D individuals and then testing it on a dataset of ten different subjects. Results with a prediction horizon of 30 min show that prediction of glucose concentration in T1D via NN is feasible and sufficiently accurate. The average time anticipation obtained is compatible with the generation of preventive hypoglycemic and hyperglycemic alerts and the improvement of artificial pancreas performance.

  12. Adaptive System Identification for Estimating Future Glucose Concentrations and Hypoglycemia Alarms.

    PubMed

    Eren-Oruklu, Meriyan; Cinar, Ali; Rollins, Derrick K; Quinn, Lauretta

    2012-08-01

    Many patients with diabetes experience high variability in glucose concentrations that includes prolonged hyperglycemia or hypoglycemia. Models predicting a subject's future glucose concentrations can be used for preventing such conditions by providing early alarms. This paper presents a time-series model that captures dynamical changes in the glucose metabolism. Adaptive system identification is proposed to estimate model parameters which enable the adaptation of the model to inter-/intra-subject variation and glycemic disturbances. It consists of online parameter identification using the weighted recursive least squares method and a change detection strategy that monitors variation in model parameters. Univariate models developed from a subject's continuous glucose measurements are compared to multivariate models that are enhanced with continuous metabolic, physical activity and lifestyle information from a multi-sensor body monitor. A real life application for the proposed algorithm is demonstrated on early (30 min in advance) hypoglycemia detection.

  13. Influence of glucose concentrations on biofilm formation, motility, exoprotease production, and quorum sensing in Aeromonas hydrophila.

    PubMed

    Jahid, Iqbal Kabir; Lee, Na-Young; Kim, Anna; Ha, Sang-Do

    2013-02-01

    Aeromonas hydrophila recently has received increased attention because it is opportunistic and a primary human pathogen. A. hydrophila biofilm formation and its control are a major concern for food safety because biofilms are related to virulence. Therefore, we investigated biofilm formation, motility inhibition, quorum sensing, and exoprotease production of this opportunistic pathogen in response to various glucose concentrations from 0.05 to 2.5% (wt/vol). More than 0.05% glucose significantly impaired (P < 0.05) quorum sensing, biofilm formation, protease production, and swarming and swimming motility, whereas bacteria treated with 0.05% glucose had activity similar to that of the control (0% glucose). A stage shift biofilm assay revealed that the addition of glucose (2.5%) inhibited initial biofilm formation but not later stages. However, addition of quorum sensing molecules N-3-butanoyl-DL-homoserine lactone and N-3-hexanoyl homoserine lactone partially restored protease production, indicating that quorum sensing is controlled by glucose concentrations. Thus, glucose present in food or added as a preservative could regulate acyl-homoserine lactone quorum sensing molecules, which mediate biofilm formation and virulence in A. hydrophila.

  14. Determination of glucose concentrations using photonic crystal LEDs

    NASA Astrophysics Data System (ADS)

    Liao, Yu-Yang; Chen, Yung-Tsan; Chang, Cheng-Yu; Lan, Wen-Yi; Huang, Jian-Jang

    2016-09-01

    As internet of things (IOT) has become a popular topic in current consumer electronics, there is a demand for cost-effective sensors to monitor bio-signals. Traditional optical sensors employ low-dimensional gratings and high-resolution spectrometers to detect the refractive index changes of the solutions. In this work, we develop an alternative approach to correlate the concentration of molecules to the band diagrams of the photonic crystals. A relatively low-resolution spectrum analyzer can be employed, yet achieves higher sensitivity than traditional approaches.

  15. 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.

  16. [Adiponectin, insulin and glucose concentrations in overweight and obese subjects after a complex carbohydrates (fiber) diet].

    PubMed

    González Rodríguez, Dora Cristina; Solano R, Liseti; González Martínez, Julio César

    2009-09-01

    Adiponectin one of the cytokines secreted by the adipose tissue that regulates the energetic metabolism through glucose and insulin interactions, stimulates the oxidation of fatty acids, reduces the plasmatic triglycerides and improves glucose metabolism by increasing insulin sensibility. Serum concentrations of adiponectin, insulin and glucose were assessed in order to establish association to weight loss after a dietary regime based on consumption of complex carbohydrates (fiber) during six weeks. Overweight and obese subjects (n=56) were studied by anthropometry. Adiponectin and insulin were measured by ELISA and glucose by Colorimetry. Data was analyzed by non parametric tests to compare independent or related samples. 12 men and 44 women, aged 20 to 55 years, 17 overweight and 39 obese were assessed. Adiponectin concentration was significantly low at basal determination in all the subjects (4,47 +/- 1,64); being higher in women (4,62 +/- 1,57 vs 3,93 +/- 1,86 microU/mL in men), while glucose and insulin values were at normal range (82,46 +/-26,51 mg/dL and 14,12 +/- 10,15 microU/mL) respectively with no significant differences for sex. Overweight subjects had significantly higher adiponectin concentrations than obese participants, at all measurements. Dietary regime promoted significant increase in adiponectin concentration at second and sixth week, with a negative correlation to body mass index and gender as they lost body weight.

  17. A non-invasive photoacoustic and ultrasonic method for the measurement of glucose solution concentration

    NASA Astrophysics Data System (ADS)

    Zhao, Siwei; Tao, Wei; He, Qiaozhi; Zhao, Hui; Cao, Wenwu

    2017-03-01

    Diabetes mellitus (DM) is a chronic disease affecting nearly 400 million people worldwide. In order to manage the disease, patients need to monitor the blood glucose level by puncturing the finger several times a day, which is uncomfortable and inconvenient. We present here a potential non-invasive monitoring method based on the velocity of ultrasonic waves generated in glucose solution by the photoacoustic principal, which can recognize the glucose concentration down to 20mg/dL. In order to apply this method to warm bodies, we carefully designed the experiment and performed measurements from 30 °C to 50 °C to generate a set of calibration curves, which may be used by engineers to build devices. Most importantly, we have theoretically explained the relationship between the compressibility and the glucose concentration. Our results show that the compressibility of solution decreases with the glucose concentration, which clarified the controversy between theory and experiment results in the literature. The derived formula is generally validity, which can be used to nondestructively measure solution concentration for other types of solutions using photoacoustic principle.

  18. 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.

  19. Influence of glucose concentration on the structure and quantity of biofilms formed by Candida parapsilosis.

    PubMed

    Pereira, Leonel; Silva, Sónia; Ribeiro, Bruno; Henriques, Mariana; Azeredo, Joana

    2015-08-01

    Candida parapsilosis is nowadays an emerging opportunistic pathogen and its increasing incidence is part related to the capacity to produce biofilm. In addition, one of the most important C. parapsilosis pathogenic risk factors includes the organisms' selective growth capabilities in hyperalimentation solutions. Thus, in this study, we investigated the role of glucose in C. parapsilosis biofilm modulation, by studying biofilm formation, matrix composition, and structure. Moreover, the expression of biofilm-related genes (BCR1, FKS1 and OLE1) was analysed in the presence of different glucose percentages. The results demonstrated the importance of glucose in the modulation of C. parapsilosis biofilm. The concentration of glucose had direct implications on the C. parapsilosis transition of yeast cells to pseudohyphae. Additionally, it was demonstrated that biofilm-related genes BCR1, FKS1, and OLE1 are involved in biofilm modulation as a result of glucose. The mechanism by which glucose enhances biofilm formation is not fully understood; however, with this study we were able to demonstrate that C. parapsilosis responds to stress conditions caused by elevated levels of glucose by upregulating genes related to biofilm formation (BCR1, FKS1 and OLE1).

  20. 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

  1. The salivary microbiome is altered in the presence of a high salivary glucose concentration

    PubMed Central

    Hartman, Mor-Li; Shi, Ping; Hasturk, Hatice; Yaskell, Tina; Vargas, Jorel; Song, Xiaoqing; Cugini, Maryann; Barake, Roula; Alsmadi, Osama; Al-Mutawa, Sabiha; Ariga, Jitendra; Soparkar, Pramod; Behbehani, Jawad; Behbehani, Kazem

    2017-01-01

    Background Type II diabetes (T2D) has been associated with changes in oral bacterial diversity and frequency. It is not known whether these changes are part of the etiology of T2D, or one of its effects. Methods We measured the glucose concentration, bacterial counts, and relative frequencies of 42 bacterial species in whole saliva samples from 8,173 Kuwaiti adolescents (mean age 10.00 ± 0.67 years) using DNA probe analysis. In addition, clinical data related to obesity, dental caries, and gingivitis were collected. Data were compared between adolescents with high salivary glucose (HSG; glucose concentration ≥ 1.0 mg/d, n = 175) and those with low salivary glucose (LSG, glucose concentration < 0.1 mg/dL n = 2,537). Results HSG was associated with dental caries and gingivitis in the study population. The overall salivary bacterial load in saliva decreased with increasing salivary glucose concentration. Under HSG conditions, the bacterial count for 35 (83%) of 42 species was significantly reduced, and relative bacterial frequencies in 27 species (64%) were altered, as compared with LSG conditions. These alterations were stronger predictors of high salivary glucose than measures of oral disease, obesity, sleep or fitness. Conclusions HSG was associated with a reduction in overall bacterial load and alterations to many relative bacterial frequencies in saliva when compared with LSG in samples from adolescents. We propose that hyperglycemia due to obesity and/or T2D results in HSG and subsequent acidification of the oral environment, leading to a generalized perturbation in the oral microbiome. This suggests a basis for the observation that hyperglycemia is associated with an increased risk of dental erosion, dental caries, and gingivitis. We conclude that HSG in adolescents may be predicted from salivary microbial diversity or frequency, and that the changes in the oral microbial composition seen in adolescents with developing metabolic disease may the consequence

  2. 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

  3. 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.

  4. 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.

  5. Dietary flaxseed lignan extract lowers plasma cholesterol and glucose concentrations in hypercholesterolaemic subjects.

    PubMed

    Zhang, Wei; Wang, Xiaobing; Liu, Yi; Tian, Haimei; Flickinger, Brent; Empie, Mark W; Sun, Sam Z

    2008-06-01

    Lignans, derived from flaxseed, are phyto-oestrogens being increasingly studied for their health benefits. An 8-week, randomised, double-blind, placebo-controlled study was conducted in fifty-five hypercholesterolaemic subjects, using treatments of 0 (placebo), 300 or 600 mg/d of dietary secoisolariciresinol diglucoside (SDG) from flaxseed extract to determine the effect on plasma lipids and fasting glucose levels. Significant treatment effects were achieved (P < 0.05 to < 0.001) for the decrease of total cholesterol (TC), LDL-cholesterol (LDL-C) and glucose concentrations, as well as their percentage decrease from baseline. At weeks 6 and 8 in the 600 mg SDG group, the decreases of TC and LDL-C concentrations were in the range from 22.0 to 24.38 % respectively (all P < 0.005 compared with placebo). For the 300 mg SDG group, only significant differences from baseline were observed for decreases of TC and LDL-C. A substantial effect on lowering concentrations of fasting plasma glucose was also noted in the 600 mg SDG group at weeks 6 and 8, especially in the subjects with baseline glucose concentrations > or = 5.83 mmol/l (lowered 25.56 and 24.96 %; P = 0.015 and P = 0.012 compared with placebo, respectively). Plasma concentrations of secoisolariciresinol (SECO), enterodiol (ED) and enterolactone were all significantly raised in the groups supplemented with flaxseed lignan. The observed cholesterol-lowering values were correlated with the concentrations of plasma SECO and ED (r 0.128-0.302; P < 0.05 to < 0.001). In conclusion, dietary flaxseed lignan extract decreased plasma cholesterol and glucose concentrations in a dose-dependent manner.

  6. Effects of rice bran oil on plasma lipid concentrations, lipoprotein composition, and glucose dynamics in mares.

    PubMed

    Frank, N; Andrews, F M; Elliott, S B; Lew, J; Boston, R C

    2005-11-01

    Plasma lipid concentrations, lipoprotein composition, and glucose dynamics were measured and compared between mares fed diets containing added water, corn oil (CO), refined rice bran oil (RR), or crude rice bran oil (CR) to test the hypothesis that rice bran oil lowers plasma lipid concentrations, alters lipoprotein composition, and improves insulin sensitivity in mares. Eight healthy adult mares received a basal diet fed at 1.5 times the DE requirement for maintenance and each of the four treatments according to a repeated 4 x 4 Latin square design consisting of four 5-wk feeding periods. Blood samples were collected for lipid analysis after mares were deprived of feed overnight at 0 and 5 wk. Glucose dynamics were assessed at 0 and 4 wk in fed mares by combined intravenous glucose-insulin tolerance tests. Plasma glucose and insulin concentrations were measured, and estimated values of insulin sensitivity (SI), glucose effectiveness, and net insulin response were obtained using the minimal model. Mean BW increased (P = 0.014) by 29 kg (range = 10 to 50 kg) over 5 wk. Mean plasma concentrations of NEFA, triglyceride (TG), and very low-density lipoprotein (VLDL) decreased (P < 0.001) by 55, 30, and 39%, respectively, and plasma high-density lipoprotein and total cholesterol (TC) concentrations increased (P < 0.001) by 15 and 12%, respectively, over 5 wk. Changes in plasma NEFA (r = 0.58; P < 0.001) and TC (r = 0.44; P = 0.013) concentrations were positively correlated with weight gain over 5 wk. Lipid components of VLDL decreased (P < 0.001) in abundance over 5 wk, whereas the relative protein content of VLDL increased by 39% (P < 0.001). Addition of oil to the basal diet instead of water lowered plasma NEFA and TG concentrations further (P = 0.002 and 0.020, respectively) and increased plasma TC concentrations by a greater magnitude (P = 0.072). However, only plasma TG concentrations and VLDL free cholesterol content were affected (P = 0.024 and 0.009, respectively

  7. Effects of AMPK activation on lipolysis in primary rat adipocytes: studies at different glucose concentrations.

    PubMed

    Szkudelski, Tomasz; Szkudelska, Katarzyna

    2017-02-01

    Adipose tissue plays a key role in energy homeostasis. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an important intracellular energy sensor. Effects of activation of AMPK by aminomidazole-4-carboxamide ribonucleotide (AICAR) on lipolysis in the rat adipocytes were determined in the presence of 3 or 12 mM glucose. Response to epinephrine or dibutyryl-cAMP was higher in the presence of 12 mM glucose. AICAR decreased lipolysis, also when glucose was replaced by alanine or succinate and without decrease in cAMP levels. AICAR attenuated epinephrine-induced decrease in adenosine triphosphate (ATP) levels, reduced glucose uptake and lactate release. These results indicate that short-term activation of AMPK by AICAR in the rat adipocytes inhibits lipolysis, due to changes in the final, followed by protein kinase A (PKA), steps of the lipolytic cascade and improves intracellular energy status. Similar effects of AICAR were observed in the presence of 3 and 12 mM glucose, which indicates that the AMPK system is operative at high glucose concentrations.

  8. The Effect of Exercise Training on Skeletal Muscle Glucose Transorter Isoform GLUT4 Concentration in the Obese Zucker Rat

    DTIC Science & Technology

    1991-05-01

    NUMBERS The Effect of Exercise Training on Skeletal Muscle Glucose Transorter Isoform GLUT4 Concentration in the Obese Zucker Rat 6. AUTHOR(S) Eric A...Zr) THE EFFECT OF EXERCISE TRAINING ON SKELETAL MUSCLE GLUCOSE TRANSPORTER ISOFORM GLUT4 CONCENTRATION IN THE OBESE ZUCKER RAT by Eric Anthony Banks...laboratory for their help. Eric A. Banks v ABSTRACT THE EFFECT OF EXERCISE TRAINING ON SKELETAL MUSCLE GLUCOSE TRANSPORTER ISOFORM GLUT4 CONCENTRATION IN

  9. Production of Mannitol from a High Concentration of Glucose by Candida parapsilosis SK26.001.

    PubMed

    Meng, Qing; Zhang, Tao; Wei, Wenting; Mu, Wanmeng; Miao, Ming

    2017-01-01

    A novel strain, SK26.001, which can produce mannitol from a high concentration of glucose without the addition of fructose, was isolated from sugarcane juice. This strain was identified as Candida parapsilosis based on 18S ribosomal RNA (rRNA) sequence analysis and the morphological and physiological-biochemical characteristics of the strain. Under optimized fermentation conditions, the mannitol concentration in shake flasks reached 68.5 g/L. When batch fermentation was performed, the fed glucose was completely consumed after 72 h, resulting in a final mannitol concentration of 80.3 g/L. Fed-batch fermentation was then performed with glucose feed. During the fed-batch process, ammonia water was added to maintain the pH at 4.0. The mannitol concentration in the fermenter reached 97.1 g/L after 120 h, with a total glucose consumption of 284 g/L.

  10. 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.

  11. A system for full Stokes vector measurement for low concentration glucose sensing

    NASA Astrophysics Data System (ADS)

    Phan, Quoc-Hung; Lo, Yu-Lung

    2016-03-01

    A high performance system for full Stokes vector measurements was developed. The proposed system comprised a polarization scanning generator (PSG) and a high accuracy polarization state analyzer (PSA) was proposed. The PSG generated full state of polarization of light by using voltage driven electro-optics modulator without using any mechanical moving parts. The PSA was employed to record the intensity of output polarized lights in a high speed manner. The accuracy of proposed system was 10-4 for all Stokes vector (S0, S1, S2, S3) measurements in the full state of polarization of lights. An application of proposed system for low concentration glucose in aqueous solution sensing with/without scattering effects was demonstrated. The sensitivity of the optical rotation angle of CB property to changes in the concentration of glucose sample was examined over the range from 0 to 0.5g/dl. The results confirm that the proposed system is able to detect glucose at fine concentration of 0.02g/dl. The linear variation of the optical rotation angle and different glucose concentration at different scattering effects was obtained. In general, the new measurement system proposed in this study provided a fast and reliable method to measure all Stokes vectors and its potential applications in biological sensing.

  12. In vitro determination of glucose concentration based on photoacoustic spectroscopy and chemometrics

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen

    2014-09-01

    Noninvasive blood glucose level (BGL) monitoring has recently become a research hotspot in the world. Photoacoustic spectroscopy is a well-established, hybrid and promising noninvasive technique, which has already drawn many researchers' attentions in recent years due to the advantage of overcoming the scattering light interference. As the preliminary exploration of photoacoustic BGL monitoring, a photoacoustic BGL monitoring set-up based on nanosecond pulsed laser with repetition rate of 20Hz and ultrasound transducer with central frequency of 9.55MHz was established in this paper. To explore the mechanism of the time resolved BGL photoacoustic signal, a series of in vitro experiments of glucose aqueous solutions were tested, the time resolved photoacoustic signals for different concentrations of glucose solutions under different output wavelengths were captured with the data average of 512 times. The peak-to-peak values of each solution were gotten at the wavelength interval of 10nm. Difference with the peak-to-peak value of pure water via subtractive spectroscopy, the characteristic wavelengths of glucose were gotten, and the optimum characteristic wavelengths were determined via data pre-processing and principle component analysis(PCA) algorithm, the calibration equation between concentration and the peak-to-peak value was gotten via multiple linear regression(MLR), and the calibration root mean square error(CRMSE) and the prediction root mean square error(PRMSE) of glucose level is all less than 10mg/dl under the correction equation.

  13. Serum concentrations of vitamins A and E in impaired glucose tolerance.

    PubMed

    Tavridou, A; Unwin, N C; Laker, M F; White, M; Alberti, K G

    1997-10-31

    Serum concentrations of vitamins A and E were measured in 32 subjects with impaired glucose tolerance (IGT) and 148 subjects with normal glucose tolerance using reversed-phase high-performance liquid chromatography. Fasting glucose, insulin and lipid concentrations were also measured. Serum vitamin A concentrations were higher in subjects with IGT 2.5 (1.1-3.4) vs. 2.1 (1.4-3.2) mumol/l [median (2.5-97.5 percentiles)] (P = 0.002), the difference remaining significant after adjustment for triglycerides (P = 0.028). There was a univariate association between vitamin A levels and insulin resistance (r = 0.164; P = 0.02) and in multivariate logistic regression analysis the relative risk of subjects with high vitamin A concentrations having IGT was 3.8 (P = 0.002). There were no differences in serum vitamin E concentrations between the groups. These data suggest that higher vitamin A concentrations found in non-insulin-dependent diabetes pre-date the onset of diabetes. Further studies are required to confirm this finding and to investigate the possibility of a role for vitamin A in the aetiology of diabetes and IGT.

  14. Carbohydrate Ingestion Before and During Soccer Match Play and Blood Glucose and Lactate Concentrations

    PubMed Central

    Russell, Mark; Benton, David; Kingsley, Michael

    2014-01-01

    Context: The ingestion of carbohydrate (CHO) before and during exercise and at halftime is commonly recommended to soccer players for maintaining blood glucose concentrations throughout match play. However, an exercise-induced rebound glycemic response has been observed in the early stages of the second half of simulated soccer-specific exercise when CHO-electrolyte beverages were consumed regularly. Therefore, the metabolic effects of CHO beverage consumption throughout soccer match play remain unclear. Objective: To investigate the blood glucose and blood lactate responses to CHOs ingested before and during soccer match play. Design: Crossover study. Setting: Applied research study. Patients or Other Participants: Ten male outfield academy soccer players (age = 15.6 ± 0.2 years, height = 1.74 ± 0.02 m, mass = 65.3 ± 1.9 kg, estimated maximal oxygen consumption = 58.4 ± 0.8 mL·kg−1·min−1). Intervention(s): Players received a 6% CHO-electrolyte solution or an electrolyte (placebo) solution 2 hours before kickoff, before each half (within 10 minutes), and every 15 minutes throughout exercise. Blood samples were obtained at rest, every 15 minutes during the match (first half: 0–15, 15–30, and 30–45 minutes; second half: 45–60, 60–75, and 75–90 minutes) and 10 minutes into the halftime break. Main Outcome Measure(s): Metabolic responses (blood glucose and blood lactate concentrations) and markers of exercise intensity (heart rate) were recorded. Results: Supplementation influenced the blood glucose response to exercise (time × treatment interaction effect: P ≤ .05), such that glucose concentrations were higher at 30 to 45 minutes in the CHO than in the placebo condition. However, in the second half, blood glucose concentrations were similar between conditions because of transient reductions from peak values occurring in both trials at halftime. Blood lactate concentrations were elevated above those at rest in the first 15 minutes of exercise

  15. Clofibrate-induced reduction of plasma branched-chain amino acid concentrations impairs glucose tolerance in rats.

    PubMed

    Kadota, Yoshihiro; Kazama, Shunsuke; Bajotto, Gustavo; Kitaura, Yasuyuki; Shimomura, Yoshiharu

    2012-05-01

    It has been reported that branched-chain amino acid (BCAA) administration stimulates glucose uptake into muscles and whole body glucose oxidation in rats. The authors examined the effect of decreased plasma BCAA concentrations induced by clofibrate treatment on glucose tolerance in rats. Since clofibrate, a drug for hyperlipidemia (high serum triglyceride concentration), is a potent inhibitor of the branched-chain α-keto acid dehydrogenase kinase, clofibrate treatment (0.2 g/kg body weight) activated the hepatic branched-chain α-keto acid dehydrogenase complex, resulting in decreased plasma BCAA concentrations by 30% to 50% from the normal level. An intraperitoneal glucose tolerance test was conducted after clofibrate administration, and the results showed that peak plasma glucose concentration and the area under the curve of glucose concentration during the intraperitoneal glucose tolerance test were significantly higher in clofibrate-treated rats than in control rats. This impaired glucose tolerance in the clofibrate-treated rats was ameliorated by administration of BCAAs (0.45 g/kg body weight, leucine:isoleucine:valine = 2:1:1), which kept plasma BCAA concentrations at normal levels during the intraperitoneal glucose tolerance test. These results suggest that plasma BCAAs play an important role in maintaining normal glucose tolerance in rats.

  16. 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

  17. 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.

  18. Metformin prevents the effects of Pseudomonas aeruginosa on airway epithelial tight junctions and restricts hyperglycaemia-induced bacterial growth.

    PubMed

    Patkee, Wishwanath R A; Carr, Georgina; Baker, Emma H; Baines, Deborah L; Garnett, James P

    2016-04-01

    Lung disease and elevation of blood glucose are associated with increased glucose concentration in the airway surface liquid (ASL). Raised ASL glucose is associated with increased susceptibility to infection by respiratory pathogens including Staphylococcus aureus and Pseudomonas aeruginosa. We have previously shown that the anti-diabetes drug, metformin, reduces glucose-induced S. aureus growth across in vitro airway epithelial cultures. The aim of this study was to investigate whether metformin has the potential to reduce glucose-induced P. aeruginosa infections across airway epithelial (Calu-3) cultures by limiting glucose permeability. We also explored the effect of P. aeruginosa and metformin on airway epithelial barrier function by investigating changes in tight junction protein abundance. Apical P. aeruginosa growth increased with basolateral glucose concentration, reduced transepithelial electrical resistance (TEER) and increased paracellular glucose flux. Metformin pre-treatment of the epithelium inhibited the glucose-induced growth of P. aeruginosa, increased TEER and decreased glucose flux. Similar effects on bacterial growth and TEER were observed with the AMP activated protein kinase agonist, 5-aminoimidazole-4-carboxamide ribonucleotide. Interestingly, metformin was able to prevent the P. aeruginosa-induced reduction in the abundance of tight junction proteins, claudin-1 and occludin. Our study highlights the potential of metformin to reduce hyperglycaemia-induced P. aeruginosa growth through airway epithelial tight junction modulation, and that claudin-1 and occludin could be important targets to regulate glucose permeability across airway epithelia and supress bacterial growth. Further investigation into the mechanisms regulating metformin and P. aeruginosa action on airway epithelial tight junctions could yield new therapeutic targets to prevent/suppress hyperglycaemia-induced respiratory infections, avoiding the use of antibiotics.

  19. 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.

  20. Real-time estimation of glucose concentration in algae cultivation system using Raman spectroscopy.

    PubMed

    Oh, Se-Kyu; Yoo, Sung Jin; Jeong, Dong Hwi; Lee, Jong Min

    2013-08-01

    This work proposes a soft-sensor design for real-time estimation of glucose concentration under mixotrophic conditions using Raman spectroscopy. The suggested approach applies a Rolling-Circle Filter (RCF), Partial Least Squares (PLS), and a successive Savitzky-Golay (SG) smoothing filter. RCF is used to remove the background effects of Raman spectrum in the pre-processing step. PLS is used to reduce the dimensionality of spectrum data and relate them to the concentration. The SG filter is further employed as a post-processing step in a successive manner to adjust predicted glucose concentrations. Two sets of experiments using artificial assays and samples from a microalgae cultivation system were performed for verification. The proposed approach showed improved prediction performances compared to other data processing and regression techniques.

  1. 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.

  2. Seasonal variations in plasma glucose and insulin concentrations after glucose loading in the edible dormouse (Glis glis L.).

    PubMed

    Castex, C; Donnio, R; Sutter, B C

    1979-01-01

    Glucose tolerance tests made in the Edible dormouse showed annual variations in B cell secretory capacity, associated with glucose tolerance changes. 1. During autumn and winter, the B cell is sensitive to glucose, and insulin regulates the high peripheral consumption of this hexose. 2. At the beginning of spring, insulin secretion decreases and glucose tolerance is impaired. In June, the B cell response si low or absent and a poor tolerance to glucose still persists. 3. The variations in B cell activity can be related to changing energy requirements during the year.

  3. 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.

  4. 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.

  5. Blood concentrations of amino acids, glucose and lactate during experimental swine dysentery.

    PubMed

    Jonasson, R; Essén-Gustavsson, B; Jensen-Waern, M

    2007-06-01

    The aim of this study was to examine blood concentrations of amino acids, glucose and lactate in association with experimental swine dysentery. Ten pigs (approximately 23kg) were orally inoculated with Brachyspira hyodysenteriae. Eight animals developed muco-haemorrhagic diarrhoea with impaired general appearance, changes in white blood cell counts and increased levels of the acute phase protein Serum Amyolid A. Blood samples were taken before inoculation, during the incubation period, during clinical signs of dysentery and during recovery. Neither plasma glucose nor lactate concentrations changed during the course of swine dysentery, but the serum concentrations of gluconeogenic non-essential amino acids decreased during dysentery. This was mainly due to decreases in alanine, glutamine, serine and tyrosine. Lysine increased during dysentery and at the beginning of the recovery period, and leucine increased during recovery. Glutamine, alanine and tyrosine levels show negative correlations with the numbers of neutrophils and monocytes. In conclusion, swine dysentery altered the blood concentrations of amino acids, but not of glucose or lactate.

  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. Simultaneous detection of pH value and glucose concentrations for wound monitoring applications.

    PubMed

    Jankowska, D A; Bannwarth, M B; Schulenburg, C; Faccio, G; Maniura-Weber, K; Rossi, R M; Scherer, L; Richter, M; Boesel, L F

    2017-01-15

    Aging population and longer life expectancy are the main reasons for an increasing number of patients with wound problems. Although the interest in wound care increases continuously, wound management still remains a challenge mainly due to the higher occurrence of chronic wounds, which require intensive care and constant monitoring. Here, we demonstrate a fluorescent sensing system to monitor the wound status and to distinguish between an autonomously healing and a chronic wound at an early stage. The system allows monitoring two of the most relevant fluctuating wound parameters during the healing process which are pH and glucose concentration. A fluorescent pH indicator dye, carboxynaphthofluorescein, and a metabolite-sensing enzymatic system, based on glucose oxidase and horseradish peroxidase, were immobilized on a biocompatible polysaccharide matrix to develop a functional hydrogel coating for wound monitoring. The changes in metabolite and enzyme concentration in artificial wound extract were converted into a fluorescent signal.

  8. Effect of glucose concentration on the rate of fructose consumption in native strains isolated from the fermentation of Agave duranguensis.

    PubMed

    Díaz-Campillo, M; Urtíz, N; Soto, O; Barrio, E; Rutiaga, M; Páez, J

    2012-12-01

    Studies on hexose consumption by Saccharomyces cerevisiae show that glucose is consumed faster than fructose when both are present (9:1 fructose to glucose) in the medium during the fermentation of Agave. The objective of this work was to select strains of S. cerevisiae that consume fructose equal to or faster than glucose at high fructose concentrations by analyzing the influence of different glucose concentrations on the fructose consumption rate. The optimal growth conditions were determined by a kinetics assay using high performance liquid chromatography (HPLC) using 50 g of glucose and 50 g of fructose per liter of synthetic medium containing peptone and yeast extract. Using the same substrate concentrations, strain ITD-00185 was shown to have a higher reaction rate for fructose over glucose. At 75 g of fructose and 25 g of glucose per liter, strain ITD-00185 had a productivity of 1.02 gL(-1) h(-1) after 40 h and a fructose rate constant of 0.071 h(-1). It was observed that glucose concentration positively influences fructose consumption when present in a 3:1 ratio of fructose to glucose. Therefore, adapted strains at high fructose concentrations could be used as an alternative to traditional fermentation processes.

  9. Effect of glucose concentration on formation of AGEs in erythrocytes in vitro.

    PubMed

    Nagai, Ryoji; Deemer, Elizabeth K; Brock, Jonathan W; Thorpe, Suzanne R; Baynes, John W

    2005-06-01

    Posttranslational modifications, such as advanced glycoxidation and lipoxidation end products (AGE/ALEs), are implicated in the pathogenesis of diabetic complications and atherosclerosis. Recent studies have demonstrated that AGE/ALEs are generated not only in extracellular matrix proteins, but also in intracellular proteins from metabolic intermediates. In this study we investigate the effect of glucose concentration on the formation of the AGE/ALEs, Nepsilon-(carboxymethyl)lysine (CML), Nepsilon-(carboxyethyl)lysine (CEL), S-(carboxymethyl)cysteine (CMC), and S-(2-succinyl)cysteine (2SC) in erythrocytes as a function of glucose concentration. Human erythrocytes (10% hematocrit) were incubated in Dulbecco's modified Eagle's medium (DMEM) containing 5 mM or 30 mM glucose for 5 days at 37 degrees C. Globin was recovered by precipitation with 0.25 M HCl in acetone. Following acid hydrolysis, amino acids were converted to their trifluoroacetyl methyl ester derivatives and analyzed by GC/MS/MS. The CML and CEL content of globin increased in a time- and glucose-dependent manner and also increased 1.3- and 1.8-fold, respectively, in incubations containing 30 mM glucose; whereas CMC and 2SC content did not change during the five-day incubations. Furthermore, CEL content of globin in erythrocytes incubated with 30 mM was the highest in the other AGEs, indicating that methylglyoxal may play a major role in AGE formation in erythrocytes. The erythrocyte system should be useful for cellular screening of the efficacy of inhibitors of AGE/ALE formation.

  10. Effect of chronic hypoglycaemia on glucose concentration and glycogen content in rat brain: a localized 13C NMR study

    PubMed Central

    Lei, Hongxia; Gruetter, Rolf

    2006-01-01

    While chronic hypoglycaemia has been reported to increase unidirectional glucose transport across the blood-brain barrier (BBB) and to increase GLUT1 expression at the endothelium, the effect on steady-state brain d-glucose and brain glycogen content is currently unknown. Brain glucose and glycogen concentrations were directly measured in vivo using localized 13C magnetic resonance spectroscopy (MRS) following 12-14 days of hypoglycaemia. Brain glucose content was significantly increased by 48%, which is consistent with an increase in the maximal glucose transport rate, Tmax, by 58% compared with the sham-treated animals. The localized 13C NMR measurements of brain glucose were directly validated by comparison with biochemically determined brain glucose content after rapid focused microwave fixation (1.4 s at 4 kW). Both in vivo MRS and biochemical measurements implied that brain glycogen content was not affected by chronic hypoglycaemia, consistent with brain glucose being a major factor controlling brain glycogen content. We conclude that the increased glucose transporter expression in chronic hypoglycaemia leads to increased brain glucose content at a given level of glycaemia. Such increased brain glucose concentrations can result in a lowered glycaemic threshold of counter-regulation observed in chronic hypoglycaemia. PMID:16987249

  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).

  12. 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

  13. Paper-based microfluidic biofuel cell operating under glucose concentrations within physiological range.

    PubMed

    González-Guerrero, Maria José; Del Campo, F Javier; Esquivel, Juan Pablo; Leech, Dónal; Sabaté, Neus

    2017-04-15

    This work addresses the development of a compact paper-based enzymatic microfluidic glucose/O2 fuel cell that can operate using a very limited sample volume (≈35µl) and explores the energy generated by glucose at concentrations typically found in blood samples at physiological conditions (pH 7.4). Carbon paper electrodes combined with a paper sample absorption substrate all contained within a plastic microfluidic casing are used to construct the paper-based fuel cell. The anode catalysts consist of glucose dehydrogenase and [Os(4,4'-dimethoxy-2,2'-bipyridine)2(poly-vinylimidazole)10Cl](+) as mediator, while the cathode catalysts were bilirubin oxidase and [Os(2,2'-bipyridine)2(poly-vinylimidazole)10Cl](+) as mediator. The fuel cell delivered a linear power output response to glucose over the range of 2.5-30mM, with power densities ranging from 20 to 90µWcm(-2). The quantification of the available electrical power as well as the energy density extracted from small synthetic samples allows planning potential uses of this energy to power different sensors and analysis devices in a wide variety of in-vitro applications.

  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.

  15. Study on the mechanism of human blood glucose concentration measuring using mid-infrared spectral analysis technology

    NASA Astrophysics Data System (ADS)

    Li, Xiang

    2016-10-01

    All forms of diabetes increase the risk of long-term complications. Blood glucose monitoring is of great importance for controlling diabetes procedure, preventing the complications and improving the patient's life quality. At present, the clinical blood glucose concentration measurement is invasive and could be replaced by noninvasive spectroscopy analytical techniques. The mid-infrared spectral region contains strong characteristic and well-defined absorption bands. Therefore, mid-infrared provides an opportunity for monitoring blood glucose invasively with only a few discrete bonds. Although the blood glucose concentration measurement using mid-infrared spectroscopy has a lot of advantages, the disadvantage is also obvious. The absorption in this infrared region is fundamental molecular group vibration. Absorption intensity is very strong, especially for biological molecules. In this paper, it figures out that the osmosis rate of glucose has a certain relationship with the blood glucose concentration. Therefore, blood glucose concentration could be measured indirectly by measuring the glucose exudate in epidermis layer. Human oral glucose tolerance tests were carried out to verify the correlation of glucose exudation in shallow layer of epidermis layer and blood glucose concentration. As it has been explained above, the mid-infrared spectral region contains well-defined absorption bands, the intensity of absorption peak around 1123 cm-1 was selected to measure the glucose and that around 1170 cm-1 was selected as reference. Ratio of absorption peak intensity was recorded for each set of measurement. The effect and importance of the cleaning the finger to be measured before spectrum measuring are discussed and also verified by experiment.

  16. Effects of basswood honey, honey-comparable glucose-fructose solution, and oral glucose tolerance test solution on serum insulin, glucose, and C-peptide concentrations in healthy subjects.

    PubMed

    Münstedt, Karsten; Sheybani, Babak; Hauenschild, Annette; Brüggmann, Dörthe; Bretzel, Reinhard G; Winter, Daniel

    2008-09-01

    Studies suggest that honey has less influence on serum glucose concentrations than monosaccharides and disaccharides. This study aimed to confirm these findings conclusively by comparing directly the effects of honey, an identical sugar solution, and oral glucose tolerance (OGT) test solution on serum glucose, insulin, and C-peptide values in healthy subjects. Twelve healthy men with a mean age of 27.7 years, a mean body mass index of 23.2 kg/m(2), and no history of metabolic disorders participated in the study. Subjects underwent OGT testing to establish values and exclude preclinical diabetes. One week later they were randomly assigned to basswood honey or a glucose-fructose solution (honey-comparable glucose-fructose solution). The following week subjects were given the other solution. All solutions contained 75 g of glucose. Serum glucose was measured before drinking test solutions and every 10 minutes for 120 minutes afterwards. C-peptide and insulin were measured at 60 and 120 minutes. Serum insulin and C-peptide values at 60 minutes were significantly lower for honey. The mean serum glucose concentration was also lower for honey, but direct comparisons at the various times showed no statistically significant differences between solutions. However, the area under the concentration-time profile for glucose response was lower for the honey than the honey-comparable glucose-fructose solution. Honey had less effect on serum glucose, C-peptide, and insulin values than the honey-comparable glucose-fructose solution. Further study to elucidate underlying mechanisms may be worthwhile, as may investigation of the implications of these findings for diabetic patients.

  17. Olanzapine-induced changes in glucose metabolism are independent of the melanin-concentrating hormone system.

    PubMed

    Girault, Elodie M; Toonen, Pim W; Eggels, Leslie; Foppen, Ewout; Ackermans, Mariëtte T; la Fleur, Susanne E; Fliers, Eric; Kalsbeek, Andries

    2013-11-01

    Atypical antipsychotic drugs such as Olanzapine (Ola) induce weight gain and metabolic changes associated with the development of type 2 diabetes. The mechanisms underlying these undesired side-effects are currently unknown. Chagnon et al. showed that the common allele rs7973796 of the prepro-melanin-concentrating hormone (PMCH) gene is associated with a greater body mass index in Ola-treated schizophrenic patients. As PMCH encodes for the orexigenic neuropeptide melanin-concentrating hormone (MCH), it was hypothesized that MCH is involved in Ola-induced metabolic changes. We have recently reported that the intragastric infusion of Ola results in hyperglycaemia and insulin resistance in male rats. In order to test in vivo the possible involvement of the PMCH gene in the pathogenesis of Ola side-effects, we administered Ola intragastrically in wild-type (WT) and PMCH knock-out (KO) rats. Our results show that glucose and corticosterone levels, as well as endogenous glucose production, are elevated by the infusion of Ola in both WT and KO animals. Thus, the lack of MCH does not seem to affect the acute effects of Ola on glucose metabolism. On the other hand, these effects might be obliterated by compensatory changes in other hypothalamic systems. In addition, possible modulatory effects of the MCH KO on the long term effects of Ola, i.e. increased adiposity, body weight gain, have not been investigated yet.

  18. Non-contact optical sensor for detection of glucose concentration using a magneto-optic effect

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    In this paper we aim to experimentally verify a speckle based technique for non-contact measurement of glucose concentration in blood stream while the vision for the final device aims to contain a single wristwatch-style device containing an AC (alternating) electro-magnet generated by a solenoid, a laser and a camera. The experiments presented in work are performed in-vitro in order to verify the effects that are responsible for the operation principle. When a glucose substance is inserted into a solenoid generating an alternating magnetic field it exhibits Faraday rotation which affects the temporal changes of the secondary speckle patterns distribution. 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.

  19. 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.

  20. Extremely high intracellular concentration of glucose-6-phosphate and NAD(H) in Deinococcus radiodurans.

    PubMed

    Yamashiro, Takumi; Murata, Kousaku; Kawai, Shigeyuki

    2017-03-01

    Deinococcus radiodurans is highly resistant to ionizing radiation and UV radiation, and oxidative stress caused by such radiations. NADP(H) seems to be important for this resistance (Slade and Radman, Microbiol Mol Biol Rev 75:133-191; Slade, Radman, Microbiol Mol Biol Rev 75:133-191, 2011), but the mechanism underlying the generation of NADP(H) or NAD(H) in D. radiodurans has not fully been addressed. Intracellular concentrations of NAD(+), NADH, NADP(+), and NADPH in D. radiodurans are also not determined yet. We found that cell extracts of D. radiodurans catalyzed reduction of NAD(P)(+) in vitro, indicating that D. radiodurans cells contain both enzymes and a high concentration of substrates for this activity. The enzyme and the substrate were attributed to glucose-6-phosphate dehydrogenase and glucose-6-phosphate of which intracellular concentration was extremely high. Unexpectedly, the intracellular concentration of NAD(H) was also much greater than that of NADP(H), suggesting some significant roles of NADH. These unusual features of this bacterium would shed light on a new aspect of physiology of this bacterium.

  1. 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.

  2. 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.

  3. Concentration of Rutin Model Solutions from Their Mixtures with Glucose Using Ultrafiltration

    PubMed Central

    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 m2 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°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

  4. Sweet talk: insights into the nature and importance of glucose transport in lung epithelium.

    PubMed

    Garnett, James P; Baker, Emma H; Baines, Deborah L

    2012-11-01

    For over 50 years, glucose has been recognised to cross the lung epithelial barrier and be transported by lung epithelial cells. However, until recently, research into these processes focused on their effects on lung liquid volume. Here, we consider a newly identified role for pulmonary glucose transport in maintaining low airway surface liquid (ASL) glucose concentrations and propose that this contributes to lung defence against infection. Glucose diffuses into ASL via paracellular pathways at a rate determined by paracellular permeability and the transepithelial glucose gradient. Glucose is removed from ASL in proximal airways via facilitative glucose transporters, down a concentration gradient generated by intracellular glucose metabolism. In the distal lung, glucose transport via sodium-coupled glucose transporters predominates. These processes vary between species but universally maintain ASL glucose at 3-20-fold lower concentrations than plasma. ASL glucose concentrations are increased in respiratory disease and by hyperglycaemia. Elevated ASL glucose in intensive care patients was associated with increased Staphylococcus aureus infection. Diabetic patients with and without chronic lung disease are at increased risk of respiratory infection. Understanding of mechanisms underlying lung glucose homeostasis could identify new therapeutic targets for control of ASL glucose and prevention and treatment of lung infection.

  5. 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)

  6. Chickpeas suppress postprandial blood glucose concentration, and appetite and reduce energy intake at the next meal.

    PubMed

    Zafar, Tasleem A; Kabir, Yearul

    2017-03-01

    The current study was designed to explore the beneficial properties of chickpeas consumption on suppressing appetite, excessive blood glucose excursions, and energy intake (EI) from a subsequent meal. Two caloric preloaded foods, chickpeas, and white bread were compared to water control, fed to healthy female subjects at equal energy density, volume, and available carbohydrate content in two experiments spanning over 60 and 120 min. Blood glucose was measured by a portable glucometer and satiety by using a visual analogue scale questionnaire at baseline and every 15 up to 60 min in both experiments and then every 30 until 120 min in Experiment 2 after the preloads ingestion. A test meal was served at the end of both experiments to calculate EI and percent energy compensation (%EC). The results suggest a reduction of 29-36% in blood glucose concentration, and 83-98% EC after the chickpeas in Experiments 1 and 2 respectively compared to white bread. The average appetite showed a positive association with EI. We conclude that the consumption of chickpeas is beneficial on glycemic control and may help in body weight management through suppressing appetite and energy intake.

  7. Correction of glucose concentration interference on Jaffé kinetic creatinine assay in peritoneal dialysis.

    PubMed

    Da Rin, G; Amici, G; Virga, G; Bardin, C; Calzavara, P; Bocci, C

    1995-01-01

    Overestimation of creatinine measurement using the Jaffé kinetic method in peritoneal dialysis solutions, due to glucose interference, has been quantified and corrected through the elaboration of linear formulas obtained from 110 recovery and 301 biological tests. The added pure powdered creatinine and enzymatic method were considered as references after proven accuracy. Considering creatinine as well as glucose concentration interference, we obtained correction formulas from multiple regression application. All the computed formulas gave satisfactory corrections but different accuracy levels. The best model in biological samples was: Corrected CR = K1JafféCr + K2Glucose (all values in mg/dl) where K1 = 0.973 and K2 = -0.00035 (Rsq = 0.987, F ratio = 10,945, p = 0.00001). Applying formulas to biological samples there was a drop in accuracy, possibly explained by the presence of numerous unidentified substances in peritoneal dialysis biological samples that can amplify scatter. Every laboratory can reduce the error of the Jaffé kinetic assay by calculating their own correction formula in relation to the method and instrument used, because Jaffé kinetic assay gives different results with different kinetic windows. So, especially when applied to peritoneal dialysis fluid measurements, if a creatinine assay reference method is not available, the correction formula can be applied directly as given. Otherwise the method we have described can be followed with a well-structured creatinine recovery fest to identify and quantify assay interferences.

  8. The sex of the foetus affects maternal blood glucose concentrations in overweight and obese pregnant women.

    PubMed

    Seneviratne, Sumudu N; Derraik, José G B; Jiang, Yannan; McCowan, Lesley M E; Gusso, Silmara; Cutfield, Wayne S; Hofman, Paul L

    2016-12-26

    There is increasing evidence that the sex of the foetus may alter the maternal metabolic milieu during pregnancy. Following a randomized controlled trial of exercise in overweight and obese pregnant women, we assessed whether the sex of the foetus was associated with changes in maternal metabolism. Data were analysed on 74 randomized participants who completed the trial, including 38 mothers carrying males and 36 mothers carrying females. At 19 weeks of gestation, mothers carrying boys had higher blood glucose concentrations than those carrying girls (5.4 vs 4.9 mmol/l; p = .046). At 36 weeks of gestation, differences were more marked, with blood glucose concentrations 15% higher in mothers carrying females (5.7 vs 5.0 mmol/l; p = .004). In addition, mothers carrying girls had higher concentrations of hs-CRP across pregnancy (5.0 vs 3.6 mg/l; p = .029). Our findings provide further evidence that the sex of the foetus appears to influence maternal metabolism.

  9. Acute postexercise effects of concentric and eccentric exercise on glucose tolerance.

    PubMed

    Cook, Matthew David; Myers, Stephen David; Kelly, John Stephen Michael; Willems, Mark Elisabeth Theodorus

    2015-02-01

    Impaired glucose tolerance was shown to be present 48 hr following muscle-damaging eccentric exercise. We examined the acute effect of concentric and muscle-damaging eccentric exercise, matched for intensity, on the responses to a 2-hr 75-g oral glucose tolerance test (OGTT). Ten men (27 ± 9 years, 178 ± 7 cm, 75 ± 11 kg, VO₂max: 52.3 ± 7.3 ml · kg⁻¹ · min⁻¹) underwent three OGTTs after an overnight 12 hr fast: rest (control), 40-min (5 × 8-min with 2-min interbout rest) of concentric (level running, 0%, CON) or eccentric exercise (downhill running, -12%, ECC). Running intensity was matched at 60% of maximal metabolic equivalent. Maximal isometric force of m. quadriceps femoris of both legs was measured before and after the running protocols. Downhill running speed was higher (level: 9.7 ± 2.1, downhill: 13.8 ± 3.2 km · hr⁻¹, p < .01). Running protocols had similar VO₂max (p = .59), heart rates (p = .20) and respiratory exchange ratio values (p = .74) indicating matched intensity and metabolic demands. Downhill running resulted in higher isometric force deficits (level: 3.0 ± 6.7, downhill: 17.1 ± 7.3%, p < .01). During OGTTs, area-under-the-curve for plasma glucose (control: 724 ± 97, CON: 710 ± 77, ECC: 726 ± 72 mmol · L⁻¹ · 120 min, p = .86) and insulin (control: 24995 ± 11229, CON: 23319 ± 10417, ECC: 21842 ± 10171 pmol · L⁻¹ · 120 min, p = .48), peak glucose (control: 8.1 ± 1.3, CON: 7.7 ± 1.2, ECC: 7.7 ± 1.1 mmol · L⁻¹, p = .63) and peak insulin levels (control: 361 ± 188, CON: 322 ± 179, ECC: 299 ± 152 pmol · L⁻¹, p = .30) were similar. It was concluded that glucose tolerance and the insulin response to an OGTT were not changed immediately by muscle-damaging eccentric exercise.

  10. Effects of glucose concentration on in vitro fertilization in BALB/c mice.

    PubMed

    Wu, H T; Chou, C K; Lin, C S; Huang, M C

    2003-12-01

    BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty. Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 mm of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively. It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa.

  11. Time- and concentration-dependent genomic responses of the rat airway to inhaled nickel subsulfide

    SciTech Connect

    Efremenko, A.Y.; Campbell, J.L.; Dodd, D.E.; Oller, A.R.; Clewell, H.J.

    2014-09-15

    Objective: To provide insights into the mode of action for Ni{sub 3}S{sub 2} lung carcinogenicity by examining gene expression changes in target cells after inhalation exposure. Methods: Gene expression changes were determined in micro-dissected lung broncho-alveolar cells from Fischer 344 rats following inhalation of Ni{sub 3}S{sub 2} at 0.0, 0.04, 0.08, 0.15, and 0.60 mg/m{sup 3} (0.03, 0.06, 0.11, and 0.44 mg Ni/m{sup 3}) for one and four weeks (6 h/day, 5 days/week). Results: Broncho-alveolar lavage fluid evaluation and lung histopathology provided evidence of inflammation only at the two highest concentrations, which were similar to those tested in the 2-year bioassay. The number of statistically significant up- and down-regulated genes decreased markedly from one to four weeks of exposure, suggesting adaptation. Cell signal pathway enrichment at both time-points primarily reflected responses to toxicity, including inflammatory and proliferative signaling. While proliferative signaling was up-regulated at both time points, some inflammatory signaling reversed from down-regulation at 1 week to up-regulation at 4 weeks. Conclusions: These results support a mode of action for Ni{sub 3}S{sub 2} carcinogenicity driven by chronic toxicity, inflammation and proliferation, leading to mis-replication, rather than by direct genotoxicity. Benchmark dose (BMD) analysis identified the lowest pathway transcriptional BMD exposure concentration as 0.026 mg Ni/m{sup 3}, for apoptosis/survival signaling. When conducted on the basis of lung Ni concentration the lowest pathway BMD was 0.64 μg Ni/g lung, for immune/inflammatory signaling. Implications: These highly conservative BMDs could be used to derive a point of departure in a nonlinear risk assessment for Ni{sub 3}S{sub 2} toxicity and carcinogenicity. - Highlights: • The mode of action for lung carcinogenicity of inhaled Ni{sub 3}S{sub 2} was investigated in rats. • Gene expression changes were determined in micro

  12. Elevated glucose concentration changes the content and cellular localization of AMPA receptors in the retina but not in the hippocampus.

    PubMed

    Castilho, A F; Liberal, J T; Baptista, F I; Gaspar, J M; Carvalho, A L; Ambrósio, A F

    2012-09-06

    Diabetic retinopathy and diabetic encephalopathy are two common complications of diabetes mellitus. The impairment of glutamatergic neurotransmission in the retina and hippocampus has been suggested to be involved in the pathogenesis of these diabetic complications. In this study, we investigated the effect of elevated glucose concentration and diabetes on the protein content and surface expression of AMPA receptor subunits in the rat retina and hippocampus. We have used two models, cultured retinal and hippocampal cells exposed to elevated glucose concentration and an animal model of streptozotocin-induced type 1 diabetes. The immunoreactivity of GluA1, GluA2 and GluA4 was evaluated by Western blot and immunocytochemistry. The levels of these subunits at the plasma membrane were evaluated by biotinylation and purification of plasma membrane-associated proteins. Elevated glucose concentration increased the total levels of GluA2 subunit of AMPA receptors in retinal neural cells, but not of the subunits GluA1 or GluA4. However, at the plasma membrane, elevated glucose concentration induced an increase of all AMPA receptor subunits. In cultured hippocampal neurons, elevated glucose concentration did not induce significant alterations in the levels of AMPA receptor subunits. In the retinas of diabetic rats there were no persistent changes in the levels of AMPA receptor subunits comparing to aged-matched control retinas. Also, no consistent changes were detected in the levels of GluA1, GluA2 or GluA4 in the hippocampus of diabetic rats. We demonstrate that elevated glucose concentration induces early changes in AMPA receptor subunits, mainly in GluA2 subunit, in retinal neural cells. Conversely, hippocampal neurons seem to remain unaffected by elevated glucose concentration, concerning the expression of AMPA receptors, suggesting that AMPA receptors are more susceptible to the stress caused by elevated glucose concentration in retinal cells than in hippocampal neurons.

  13. Infiltrated photonic crystal cavity as a highly sensitive platform for glucose concentration detection

    NASA Astrophysics Data System (ADS)

    Arafa, Safia; Bouchemat, Mohamed; Bouchemat, Touraya; Benmerkhi, Ahlem; Hocini, Abdesselam

    2017-02-01

    A Bio-sensing platform based on an infiltrated photonic crystal ring shaped holes cavity-coupled waveguide system is proposed for glucose concentration detection. Considering silicon-on-insulator (SOI) technology, it has been demonstrated that the ring shaped holes configuration provides an excellent optical confinement within the cavity region, which further enhances the light-matter interactions at the precise location of the analyte medium. Thus, the sensitivity and the quality factor (Q) can be significantly improved. The transmission characteristics of light in the biosensor under different refractive indices that correspond to the change in the analyte glucose concentration are analyzed by performing finite-difference time-domain (FDTD) simulations. Accordingly, an improved sensitivity of 462 nm/RIU and a Q factor as high as 1.11х105 have been achieved, resulting in a detection limit of 3.03х10-6 RIU. Such combination of attributes makes the designed structure a promising element for performing label-free biosensing in medical diagnosis and environmental monitoring.

  14. 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.

  15. Small elevations of glucose concentration redirect and amplify the synthesis of guanosine 5'-triphosphate in rat islets.

    PubMed Central

    Metz, S A; Meredith, M; Rabaglia, M E; Kowluru, A

    1993-01-01

    Recent studies suggest a permissive requirement for guanosine 5'-triphosphate (GTP) in insulin release, based on the use of GTP synthesis inhibitors (such as myocophenolic acid) acting at inosine monophosphate (IMP) dehydrogenase; herein, we examine the glucose dependency of GTP synthesis. Mycophenolic acid inhibited insulin secretion equally well after islet culture at 7.8 or 11.1 mM glucose (51% inhibition) but its effect was dramatically attenuated when provided at < or = 6.4 mM glucose (13% inhibition; P < 0.001). These observations were explicable by a stimulation of islet GTP synthesis derived from IMP since, at high glucose: (a) total GTP content was augmented; (b) a greater decrement in GTP (1.75 vs. 1.05 pmol/islet) was induced by mycophenolic acid; and (c) a smaller "pool" of residual GTP persisted after drug treatment. Glucose also accelerated GTP synthesis from exogenous guanine ("salvage" pathway) and increased content of a pyrimidine, uridine 5'-triphosphate (UTP), suggesting that glucose augments production of a common regulatory intermediate (probably 5-phosphoribosyl-1-pyrophosphate). Pathway-specific radiolabeling studies confirmed that glucose tripled both salvage and de novo synthesis of nucleotides. We conclude that steep changes in the biosynthesis of cytosolic pools of GTP occur at modest changes in glucose concentrations, a finding which may have relevance to the adaptive (patho) physiologic responses of islets to changes in ambient glucose levels. PMID:8349822

  16. Capillary blood sampling from the ear of dogs and cats and use of portable meters to measure glucose concentration.

    PubMed

    Wess, G; Reusch, C

    2000-02-01

    Two new methods for collection of capillary blood from the ear of dogs and cats for the measurement of blood glucose concentration using portable blood glucose meters (PBGMs) are described. The first method uses a lancing device after pre-warming the ear, while the second employs a vacuum lancing device. Both methods generated blood drops of adequate size, although the latter method was faster and easier to perform. Accuracy of the two PBGMs was evaluated clinically and statistically. Although assessment of statistical accuracy revealed differences between the PBGMs and the reference method, all of the PBGM readings were within clinically acceptable ranges. Measurement of capillary blood glucose concentration is easy to perform, inexpensive and fast. It may be used by owners to determine blood glucose concentrations at home, and could serve as a new tool for monitoring diabetic dogs and cats.

  17. [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.

  18. Adenosine deaminase 1 and concentrative nucleoside transporters 2 and 3 regulate adenosine on the apical surface of human airway epithelia: implications for inflammatory lung diseases.

    PubMed

    Hirsh, Andrew J; Stonebraker, Jaclyn R; van Heusden, Catja A; Lazarowski, Eduardo R; Boucher, Richard C; Picher, Maryse

    2007-09-11

    Adenosine is a multifaceted signaling molecule mediating key aspects of innate and immune lung defenses. However, abnormally high airway adenosine levels exacerbate inflammatory lung diseases. This study identifies the mechanisms regulating adenosine elimination from the apical surface of human airway epithelia. Experiments conducted on polarized primary cultures of nasal and bronchial epithelial cells showed that extracellular adenosine is eliminated by surface metabolism and cellular uptake. The conversion of adenosine to inosine was completely inhibited by the adenosine deaminase 1 (ADA1) inhibitor erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA). The reaction exhibited Km and Vmax values of 24 microM and 0.14 nmol x min(-1) x cm(-2). ADA1 (not ADA2) mRNA was detected in human airway epithelia. The adenosine/mannitol permeability coefficient ratio (18/1) indicated a minor contribution of paracellular absorption. Adenosine uptake was Na+-dependent and was inhibited by the concentrative nucleoside transporter (CNT) blocker phloridzin but not by the equilibrative nucleoside transporter (ENT) blocker dipyridamole. Apparent Km and Vmax values were 17 microM and 7.2 nmol x min(-1) x cm(-2), and transport selectivity was adenosine = inosine = uridine > guanosine = cytidine > thymidine. CNT3 mRNA was detected throughout the airways, while CNT2 was restricted to nasal epithelia. Inhibition of adenosine elimination by EHNA or phloridzin raised apical adenosine levels by >3-fold and stimulated IL-13 and MCP-1 secretion by 6-fold. These responses were reproduced by the adenosine receptor agonist 5'-(N-ethylcarboxamido)adenosine (NECA) and blocked by the adenosine receptor antagonist, 8-(p-sulfophenyl) theophylline (8-SPT). This study shows that adenosine elimination on human airway epithelia is mediated by ADA1, CNT2, and CNT3, which constitute important regulators of adenosine-mediated inflammation.

  19. Oral green tea catechins transiently lower plasma glucose concentrations in female db/db mice.

    PubMed

    Wein, Silvia; Schrader, Eva; Rimbach, Gerald; Wolffram, Siegfried

    2013-04-01

    Polyphenols, including green tea catechins, are secondary plant compounds often discussed in the context of health-promoting potential. Evidence for such effects is mainly derived from epidemiological and cell culture studies. The aim of the present study was to investigate antidiabetic, antiadipogenic, and anti-inflammatory effects at nonpharmacological doses in an obese diabetic mouse model that exerts early relevant clinical signs of non-insulin-dependent diabetes mellitus. Female db/db mice received a flavonoid-poor diet either without additive, with rosiglitazone (RSG, 0.02 g/kg diet), or with green tea extract (low-dose green tea extract [LGTE] and high-dose green tea extract [HGTE], 0.1 and 1 g/kg diet). Food and water were freely available. The body weight was monitored weekly. Blood was sampled (12-h fasted) from the tail vein on day 28 and analyzed for glucose, cholesterol, triacylglycerol, nonesterified fatty acids, insulin, adiponectin, and soluble intercellular adhesion molecule-1 (sICAM-1). Blood glucose was also analyzed on day 14. Furthermore, sICAM-1 release was investigated in tumor necrosis factor alpha-stimulated EAhy926 cells. After 14 days, fasting glycemia was improved by RSG or HGTE supplementation compared to controls. However, at the end of the study (day 28), only RSG exhibited glucose-lowering effects and induced plasma adiponectin concentrations, paralleled by higher body weight gain and reduced periuterine fat pads compared to controls. However, only GTE treatment reduced sICAM-1 release in vitro and in vivo. Nonpharmacological HGTE supplementation in db/db mice caused (1) no adiponectin-inducing or antiadipogenic effects, (2) reduced sICAM-1 release, thereby potentially exerting anti-inflammatory effects in the progressive diabetic state, and (3) a transient improvement in glycemia.

  20. Behavior of plastic and metal ameroid constrictors during in vitro incubation in physiologic solutions of varying glucose concentration.

    PubMed

    Griffin, Maureen A; Hunt, Geraldine B; Epstein, Steven E

    2016-04-01

    The objective of this study was to evaluate the influence of ameroid constrictor (AC) composition as well as glucose concentration in the surrounding fluid on the rate and completeness of AC closure. In a pilot study, four ACs (two metal, two plastic) were incubated in a solution containing 100 mg/dL glucose, and in a follow-up study, two additional ACs (one metal, one plastic) were incubated in a solution of 100 mg/dL glucose and six ACs (three metal, three plastic) were incubated in a solution of 50 mg/dL glucose. Dimensions of the ACs were analyzed weekly for 57 days. No significant difference was found in the rate or overall proportionate closure for either metal versus plastic ACs or ACs incubated in 50 mg/dL versus 100 mg/dL glucose. As there was no statistically significant difference in the proportionate closure of metal and plastic ACs, both types are clinically suitable for gradual attenuation of portosystemic shunts in animal patients. The lack of a significant difference in rate and completeness of closure of ACs incubated in different concentrations of glucose provides evidence that the glucose concentration of the surrounding fluid likely does not have a significant effect on AC closure. However, a significant difference in the proportionate closure of ACs occurred within the first week of the study between constrictors incubated in 50 mg/dL glucose and those incubated in 100 mg/dL glucose, and additional studies are indicated to determine the significance of this early difference in vivo.

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

    PubMed Central

    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/m2; 5 men, 4 women) consumed 1) a control meal (∼800 kcal; 100 g of carbohydrate, 31 g of fat, and 30 g of protein), 2) a low-fat meal (∼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 (∼30 g) provided via an intravenous lipid infusion]. All three meals contained [13C]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 [13C]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 YY3-36 (PYY3-36). The recovery of the ingested [13C]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 μM·h, respectively]. However, removing dietary fat from the meal did not affect the plasma concentration of glucose or insulin. Importantly, [13C]glucose recovery was not different during the low-fat and lipid infusion trials (AUC: 1,206 ± 252 and 1,134 ± 247 μM·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 PYY3-36. In summary, these data suggest that removing fat from the diet expedited exogenous glucose delivery into the systemic circulation

  2. A low frequency electromagnetic sensor for indirect measurement of glucose concentration: in vitro experiments in different conductive solutions.

    PubMed

    Tura, Andrea; Sbrignadello, Stefano; Cianciavicchia, Domenico; Pacini, Giovanni; Ravazzani, Paolo

    2010-01-01

    In recent years there has been considerable interest in the study of glucose-induced dielectric property variations of human tissues as a possible approach for non-invasive glycaemia monitoring. We have developed an electromagnetic sensor, and we tested in vitro its ability to estimate variations in glucose concentration of different solutions with similarities to blood (sodium chloride and Ringer-lactate solutions), differing though in the lack of any cellular components. The sensor was able to detect the effect of glucose variations over a wide range of concentrations (∼78-5,000 mg/dL), with a sensitivity of ∼0.22 mV/(mg/dL). Our proposed system may thus be useful in a new approach for non-invasive and non-contact glucose monitoring.

  3. Noninvasive monitoring of blood glucose concentration in diabetic patients with optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Lan, Y. T.; Kuang, Y. P.; Zhou, L. P.; Wu, G. Y.; Gu, P. C.; Wei, H. J.; Chen, K.

    2017-03-01

    Optical coherence tomography (OCT) has been used to noninvasively monitor the blood glucose concentration (BGC) in healthy subjects with good accuracy and acceptable specificity. Based on this, the paper further considered the possibility of OCT in noninvasive monitoring BGC in diabetic patients. The OCT signal slope (OCTSS) changed with variation of BGC. The correlation coefficient R between BGC and OCTSS in diabetic patients was 0.91; while the correlation coefficient R in healthy volunteers was 0.78. Thus, a better linear dependence of OCTSS on BGC in diabetic patients was presented in the experiment. The results showed that the capability and accuracy of OCT in noninvasive monitoring BGC of diabetic patients, and the noninvasive monitoring BGC in diabetic patients may be better than the monitoring in the healthy subjects.

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

    PubMed

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

    2015-12-01

    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.

  5. 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.

  6. Determination of glucose concentration in tissue-like material using spatially resolved steady-state diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Hjalmarsson, Pär; Thennadil, Suresh N.

    2008-02-01

    An important parameter in medical diagnostic and one of the most frequently determined analyte in the hospitals is blood glucose. Fast and accurate methods of measuring blood glucose concentrations could therefore be significant. We will in this paper investigate the feasibility of using a spatially resolved steady-state diffuse reflectance spectroscopy in the wavelength region 1000-1700nm, where glucose has two absorption peaks at around 1250nm and 1600nm, to quickly determine the concentration of glucose in tissue-like material. This method could later be transferred to estimate the amount of glucose in blood both in vivo e.g. the forearm and in vitro e.g. on blood samples. The novel spatially resolved system that is used for this study is based around a 2D InGaAs detector and a fibre probe with 10 fibres, one as a source and 9 to collect the diffuse reflected light at distances between 0.3-2.7mm from the source. An inversion method using Monte Carlo generated diffuse reflectance profiles is used to estimate the absolute absorption coefficient (μ a) and reduced scattering coefficient (μ s') which could be used to estimate the glucose concentration in the tissue-like phantoms. The method was investigated by performing spatially resolved measurements on turbid gelatin phantoms containing mixtures of water and D IIO as absorbers, Intralipid as a scatterer and glucose. The phantoms were made with four different glucose concentrations spanning the range of 0-5000 mg/dl.

  7. End-tidal sevoflurane concentration for ProSeal(TM) versus Classic(TM) laryngeal mask airway insertion in unpremedicated anaesthetised adult females.

    PubMed

    Ghai, B; Jain, K; Bansal, D; Bhatia, N

    2016-03-01

    The optimal end-tidal sevoflurane concentration for successful ProSealTM (Teleflex, Morrisville, NC, USA) laryngeal mask airway (PLMA) versus ClassicTM (Teleflex, Morrisville, NC, USA) laryngeal mask airway (CLMA) insertion in unpremedicated anaesthetised adults is unknown. We determined end-tidal sevoflurane concentrations for successful insertion in fifty percent of anaesthetised adults. This randomised, prospective, double-blind study was conducted in the operating theatre of a government tertiary care hospital. Forty-four unpremedicated American Society of Anesthesiologists physical status I and II women with cervical carcinoma (aged 30 to 60 years), scheduled for intracavity caesium implantation under general anaesthesia with a laryngeal mask airway (LMA) were included in the study. The participants were randomised to one of the two groups, to receive either a PLMA or CLMA. After anaesthetic induction with sevoflurane, a predetermined end-tidal sevoflurane concentration (starting at 2.5%) was sustained for 10 minutes before LMA insertion was attempted. End-tidal sevoflurane concentration was increased/decreased (step-size 0.25%) using Dixon and Massey's up-and-down method for the next patient based on the previous patient's response. Placement without clenching, movement, coughing or biting within one minute was considered successful insertion. The end-tidal sevoflurane concentration required for successful LMA insertion in fifty percent of anaesthetised adults was calculated as the mean of the crossover pairs' midpoints in each group and further confirmed by probit regression analysis. The end-tidal sevoflurane concentration (95% confidence interval) required for successful PLMA insertion in 50% of anaesthetised adults (3.15% [3.12% to 3.18%]) was significantly higher than that for CLMA insertion (2.71% [2.66% to 2.76%], P<0.001). These findings suggest that deeper anaesthesia is required for placement of a PLMA in comparison to a CLMA.

  8. Temperature insensitive prediction of glucose concentration in turbid medium using multivariable calibration based on external parameter orthogonalization

    NASA Astrophysics Data System (ADS)

    Han, Tongshuai; Zhang, Ziyang; Sun, Cuiying; Guo, Chao; Sun, Di; Liu, Jin

    2016-10-01

    The measurement accuracy of non-invasive blood glucose concentration (BGC) sensing with near-infrared spectroscopy is easily affected by the temperature variation in tissue because it would induce an unacceptable spectrum variation and the consequent prediction deviation. We use a multivariable correction method based on external parameter orthogonalization (EPO) to calibrate the spectral data recorded at different temperature values to reduce the spectral variation. The tested medium is a kind of tissue phantom, the Intralipid aqueous solution. The calibration uses a projection matrix to get the orthogonal spectral space to the variable of external parameter, i.e. temperature, and then the useful spectral information relative to glucose concentration has been reserved. Even more, training the projection matrix can be separated to building the calibration matrix for the prediction of glucose concentration as it only uses the representative samples' data with temperature variation. The method presents a lower complexity than modeling a robust prediction matrix, which can be built from comprehensive spectral data involved the all variables both of BGC and temperature. In our test, the calibrated spectra with the same glucose concentration but different temperature values show a significantly improved repeatability. And then the glucose concentration prediction results show a lower root mean squared error of prediction (RMSEP) than that using the robust calibration model, which has considered the two variables. We also discuss the rationality of the representative samples chosen by EPO. This research may be referenced to the temperature calibration for in vivo BGC sensing.

  9. Portal vein and systemic adiponectin concentrations are closely linked with hepatic glucose and lipoprotein kinetics in extremely obese subjects.

    PubMed

    Magkos, Faidon; Fabbrini, Elisa; Patterson, Bruce W; Eagon, J Christopher; Klein, Samuel

    2011-11-01

    Low systemic plasma adiponectin concentrations are associated with abnormalities in hepatic glucose and lipoprotein metabolism in obese people. However, the relationship between the delivery of adiponectin to the liver via the portal vein and hepatic glucose and lipoprotein metabolism is not known. We examined the relationship between hepatic substrate metabolism (glucose rate of appearance into plasma and hepatic very low-density lipoprotein [VLDL]-triglyceride [TG] and VLDL-apolipoprotein B-100 [apoB-100] secretion rates, determined by using stable isotope-labeled tracer techniques) and portal vein adiponectin concentration, in 8 insulin-resistant, extremely obese subjects (body mass index, 65 ± 7 kg/m(2)). Portal vein adiponectin concentration was inversely associated with basal glucose rate of appearance (r = -0.820, P = .013) and VLDL-TG (r = -0.823, P = .012) and VLDL-apoB-100 (r = -0.787, P = .020) secretion rates. Very similar correlations were obtained for radial artery adiponectin as a result of a mirroring relationship between portal and arterial adiponectin concentrations (r = 0.899, P = .002) and the absence of significant arteriovenous concentration differences (P = .570). Insulin resistance, assessed with the homeostasis model assessment score, was also strongly associated with hepatic glucose and lipid metabolic parameters, as well as with adiponectin concentrations in the portal vein and radial artery. These results suggest that adiponectin delivery to the liver, whether via the portal or the systemic circulation, may be an important regulator of basal hepatic glucose, VLDL-TG, and VLDL-apoB-100 production rates in obese people, possibly through direct effects on the liver or changes in hepatic insulin sensitivity. However, portal vein adiponectin does not appear to be superior to arterial adiponectin as a marker of hepatic metabolic dysregulation. Additional studies are needed to elucidate the mechanism(s) responsible for the strong association

  10. Photoacoustic spectroscopy that uses a resonant characteristic of a microphone for in vitro measurements of glucose concentration.

    PubMed

    Joo Yong Sim; Chang-Geun Ahn; Eunju Jeong; Bong Kyu Kim

    2016-08-01

    Glucose measurements using photoacoustic spectroscopy have been highlighted to be a modality for non-invasive glucose monitoring. Previous photoacoustic spectroscopy for glucose measurements have used a resonant acoustic cell with a broadband capacitive microphone to increase sensitivity. However, a resonant characteristic of a microphone has not been investigated yet due to the working frequency range much lower than the resonance frequency of the microphone membrane. We, here, present a photoacoustic spectroscopy system that utilizes an ultrasound resonance of a microphone to increase sensitivity. We found that matching the resonance of a photoacoustic cell with the resonance of a microphone can increase signal-to-noise ratio and our system can distinguish the glucose concentration in liquid.

  11. 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.

  12. 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.

  13. Pioglitazone acutely reduces insulin secretion and causes metabolic deceleration of the pancreatic beta-cell at submaximal glucose concentrations.

    PubMed

    Lamontagne, Julien; Pepin, Emilie; Peyot, Marie-Line; Joly, Erik; Ruderman, Neil B; Poitout, Vincent; Madiraju, S R Murthy; Nolan, Christopher J; Prentki, Marc

    2009-08-01

    Thiazolidinediones (TZDs) have beneficial effects on glucose homeostasis via enhancement of insulin sensitivity and preservation of beta-cell function. How TZDs preserve beta-cells is uncertain, but it might involve direct effects via both peroxisome proliferator-activated receptor-gamma-dependent and -independent pathways. To gain insight into the independent pathway(s), we assessed the effects of short-term (glucose-induced insulin secretion (GIIS), AMP-activated protein kinase (AMPK) activation, and beta-cell metabolism in INS 832/13 beta-cells and rat islets. Pio caused a right shift in the dose-dependence of GIIS, such that insulin release was reduced at intermediate glucose but unaffected at either basal or maximal glucose concentrations. This was associated in INS 832/13 cells with alterations in energy metabolism, characterized by reduced glucose oxidation, mitochondrial membrane polarization, and ATP levels. Pio caused AMPK phosphorylation and its action on GIIS was reversed by the AMPK inhibitor compound C. Pio also reduced palmitate esterification into complex lipids and inhibited lipolysis. As for insulin secretion, the alterations in beta-cell metabolic processes were mostly alleviated at elevated glucose. Similarly, the antidiabetic agents and AMPK activators metformin and berberine caused a right shift in the dose dependence of GIIS. In conclusion, Pio acutely reduces glucose oxidation, energy metabolism, and glycerolipid/fatty acid cycling of the beta-cell at intermediate glucose concentrations. We suggest that AMPK activation and the metabolic deceleration of the beta-cell caused by Pio contribute to its known effects to reduce hyperinsulinemia and preserve beta-cell function and act as an antidiabetic agent.

  14. Positive Feedback Amplifies the Response of Mitochondrial Membrane Potential to Glucose Concentration in Clonal Pancreatic Beta Cells.

    PubMed

    Gerencser, Akos A; Mookerjee, Shona A; Jastroch, Martin; Brand, Martin D

    2016-10-20

    Analysis of the cellular mechanisms of metabolic disorders, including type 2 diabetes mellitus, is complicated by the large number of reactions and interactions in metabolic networks. Metabolic control analysis with appropriate modularization is a powerful method for simplifying and analyzing these networks. To analyze control of cellular energy metabolism in adherent cell cultures of the INS-1 832/13 pancreatic β-cell model we adapted our microscopy assay of absolute mitochondrial membrane potential (ΔψM) to a fluorescence microplate reader format, and applied it in conjunction with cell respirometry. In these cells the sensitive response of ΔψM to extracellular glucose concentration drives glucose-stimulated insulin secretion. Using metabolic control analysis we identified the control properties that generate this sensitive response. Force-flux relationships between ΔψM and respiration were used to calculate kinetic responses to ΔψM of processes both upstream (glucose oxidation) and downstream (proton leak and ATP turnover) of ΔψM. The analysis revealed that glucose-evoked ΔψM hyperpolarization is amplified by increased glucose oxidation activity caused by factors downstream of ΔψM. At high glucose, the hyperpolarized ΔψM is stabilized almost completely by the action of glucose oxidation, whereas proton leak also contributes to the homeostatic control of ΔψM at low glucose. These findings suggest a strong positive feedback loop in the regulation of β-cell energetics, and a possible regulatory role of proton leak in the fasting state. Analysis of islet bioenergetics from published cases of type 2 diabetes suggests that disruption of this feedback can explain the damaged bioenergetic response of β-cells to glucose.

  15. Relationships between body weight, fasting blood glucose concentration, sex and age in tree shrews (Tupaia belangeri chinensis).

    PubMed

    Wu, X; Chang, Q; Zhang, Y; Zou, X; Chen, L; Zhang, L; Lv, L; Liang, B

    2013-12-01

    The tree shrew (Tupaia belangeri chinensis) is a squirrel-like lower primate or a close relative of primates, commonly used as an animal model in biomedical research. Despite more than three decades of usage in research, the clear relationships between body weight, fasting blood glucose concentration, sex and age among tree shrews remain unclear. Based on an investigation of 992 tree shrews (454 males and 538 females) aged between 4 months and 4 years old, we found that male tree shrews have significantly higher body weight and fasting blood glucose concentration than female tree shrews (p < 0.001). The concentration of fasting blood glucose slightly increased with body weight in males (r = 0.152, p < 0.001). Meanwhile, in females, the body weight, concentration of fasting blood glucose and waist circumference positively increased with age (p < 0.001). Additionally, 17 tree shrews with Lee index [body weight (g)*0.33*1000/body length (cm)] above 290 had significantly higher body weight, waist circumference and glycated haemoglobin A1c (HbA1c) than non-obese tree shrews with a Lee index score below 290 (p < 0.001). Interestingly, 6 of 992 tree shrews (three males and three females, 2-4 years old) displayed impaired plasma triglycerides, HbA1c, low-density lipoprotein and oral glucose tolerance test, suggestive of the early symptoms of metabolic syndrome. This study provides the first clear relationships between body weight, fasting blood glucose concentration, sex and age in tree shrews, further improving our understanding of this relationship in metabolic syndrome (MetS). Given the similarity of tree shrews to humans and non-human primates, this finding supports their potential use as an animal model in the research of MetS.

  16. Evaluation of short-term predictors of glucose concentration in type 1 diabetes combining feature ranking with regression models.

    PubMed

    Georga, Eleni I; Protopappas, Vasilios C; Polyzos, Demosthenes; Fotiadis, Dimitrios I

    2015-12-01

    Glucose concentration in type 1 diabetes is a function of biological and environmental factors which present high inter-patient variability. The objective of this study is to evaluate a number of features, which are extracted from medical and lifestyle self-monitoring data, with respect to their ability to predict the short-term subcutaneous (s.c.) glucose concentration of an individual. Random forests (RF) and RReliefF algorithms are first employed to rank the candidate feature set. Then, a forward selection procedure follows to build a glucose predictive model, where features are sequentially added to it in decreasing order of importance. Predictions are performed using support vector regression or Gaussian processes. The proposed method is validated on a dataset of 15 type diabetics in real-life conditions. The s.c. glucose profile along with time of the day and plasma insulin concentration are systematically highly ranked, while the effect of food intake and physical activity varies considerably among patients. Moreover, the average prediction error converges in less than d/2 iterations (d is the number of features). Our results suggest that RF and RReliefF can find the most informative features and can be successfully used to customize the input of glucose models.

  17. Infusion of fluoxetine, a serotonin reuptake inhibitor, in the shell region of the nucleus accumbens increases blood glucose concentrations in rats.

    PubMed

    Diepenbroek, C; Rijnsburger, M; Eggels, L; van Megen, K M; Ackermans, M T; Fliers, E; Kalsbeek, A; Serlie, M J; la Fleur, S E

    2017-01-10

    The brain is well known to regulate blood glucose, and the hypothalamus and hindbrain, in particular, have been studied extensively to understand the underlying mechanisms. Nuclei in these regions respond to alterations in blood glucose concentrations and can alter glucose liver output or glucose tissue uptake to maintain blood glucose concentrations within strict boundaries. Interestingly, several cortico-limbic regions also respond to alterations in glucose concentrations and have been shown to project to hypothalamic nuclei and glucoregulatory organs. For instance, electrical stimulation of the shell of the nucleus accumbens (sNAc) results in increased circulating concentrations of glucose and glucagon and activation of the lateral hypothalamus (LH). Whether this is caused by the simultaneous increase in serotonin release in the sNAc remains to be determined. To study the effect of sNAc serotonin on systemic glucose metabolism, we implanted bilateral microdialysis probes in the sNAc of male Wistar rats and infused fluoxetine, a serotonin reuptake inhibitor, or vehicle after which blood glucose, endogenous glucose production (EGP) and glucoregulatory hormones were measured. Fluoxetine in the sNAc for 1h significantly increased blood glucose concentrations without an effect on glucoregulatory hormones. This increase was accompanied by a higher EGP in the fluoxetine infused rats compared to the controls. These data provide further evidence for a role of sNAc-serotonin in the regulation of glucose metabolism.

  18. Serum thyroid hormone, insulin, glucose, triglycerides and protein concentrations in normal horses: association with topical dexamethasone usage.

    PubMed

    Abraham, Getu; Allersmeier, Maren; Schusser, Gerald F; Ungemach, Fritz R

    2011-06-01

    The aim of this study was to determine if topical application of dexamethasone affected the serum concentrations of thyroid hormones (triiodothyronine T(3) and thyroxine T(4)), glucose, triglycerides, total protein and insulin in normal horses. Ten horses were treated twice daily for 10 days with 50 g dexamethasone using an ointment formulation. Thyroid hormones and insulin were assayed using standard radioimmunoassay methods, while glucose, triglycerides and total protein were determined using a standard enzymatic method and the Biuret reaction, respectively. An increase in serum glucose and triglyceride concentrations was accompanied by 2-6-fold increases in serum insulin concentrations, but there was no change in serum total protein concentration. Insulin secretion increased with concomitant hyperglycemia and hypertriglyceridemia. A non-significant decline in T(4) secretion was noted. Serum T(3) and T(4) concentrations declined continuously below baseline values from 48 h. Glucose and insulin levels returned to baseline values 3 days after treatment withdrawal, whereas triglycerides reverted to baseline by 7 days. In contrast, baseline values of serum T(3) and T(4) were not reached by 20 days following drug withdrawal. The results indicated that topical administration of dexamethasone affected thyroid function and physiological metabolic functions, which may have implications for potential doping cases in racing horses.

  19. Correlation between Bethatrophin and 25(OH)D Concentrations in a Group of Subjects With Normal and Impaired Glucose Metabolism.

    PubMed

    Turkon, H; Yalcın, H; Toprak, B; Demirpençe, M; Yaşar, H Y; Colak, A

    2016-02-24

    Aim: Inducing beta cell replication is a potential therapeutic approach for the treatment of diabetes mellitus. Recently betatrophin was suggested as a novel stimulator of beta cell proliferation in mice but its role in humans remains to be established. We aimed to investigate betatrophin concentration and its association with metabolic parameters in a group of individuals with normal glucose tolerance, pre-diabetes and diabetes mellitus who had not been previously treated. Methods: A total of 72 subjects were recruited for this cross sectional study: 23 subjects with normal glucose tolerance (NGT), 22 subjects with prediabetes, and 27 subjects with diabetes mellitus (DM). Circulating betatrophin concentration, 75 g oral glucose tolerance test, fasting insulin, glycosylated hemoglobin, 25hydroxy vitamin D and HOMA IR were measured. Results: The difference in betatrophin values did not reach statistical significance between the 3 groups [NGT:206 (176-297)pg/mL, Prediabetes:232 (181-254)pg/mL, DM:245 (205-526)pg/mL, p=0.078]. Betatrophin was negatively significantly correlated with BMI and positively significantly correlated with 25(OH)vitD (p=0.043 and p=0.001 respectively). Multivariate linear regression showed that 25(OH) vitD (β=0.440 p=0.001) and fasting glucose (β=0.003 p=0.038) were variables associated with betatrophin concentration (R2=0.251). Conclusions: In a group of subjects ranging from those with normal glucose tolerance to newly diagnosed diabetes, we found that 25(OH)D and fasting glucose were factors associated with serum betatrophin concentration.

  20. Comparison of jet injector and insulin pen in controlling plasma glucose and insulin concentrations in type 2 diabetic patients.

    PubMed

    Guo, Lixin; Xiao, Xinhua; Sun, Xue; Qi, Cuijuan

    2017-01-01

    This study is conducted to investigate efficacy of an insulin jet injector and an insulin pen in treatment of type 2 diabetic patients. Sixty patients with type 2 diabetes were treated with rapid-acting insulin (regular insulin) and insulin analog (insulin aspart) using the jet injector and the pen in 4 successive test cycles. Postprandial glucose and insulin concentrations in blood were measured over time. Areas under curves of glucose and the insulin were calculated, and efficacy of 2 injection methods in treatment of the diabetes was compared. Regular insulin and insulin aspart administration by the jet injector showed significant decreases in plasma glucose levels as compared to the pen injection (P < 0.05). Postprandial plasma glucose excursions at the time points of 0.5 to 3 hours were obviously lower in the jet-treated patients than the pen-treated ones (P < 0.05). Postprandial plasma insulin levels were markedly higher in the jet-treated patients than the pen-treated ones (P < 0.05). Area under the glucose curve in the pen-treated patients was significantly increased as compared to the jet-treated ones (P < 0.01). Efficacy of the insulin jet injector in treatment of type 2 diabetic patients is obviously superior to the insulin pen in regulating plasma glucose and insulin levels.

  1. Comparison of jet injector and insulin pen in controlling plasma glucose and insulin concentrations in type 2 diabetic patients

    PubMed Central

    Guo, Lixin; Xiao, Xinhua; Sun, Xue; Qi, Cuijuan

    2017-01-01

    Abstract This study is conducted to investigate efficacy of an insulin jet injector and an insulin pen in treatment of type 2 diabetic patients. Sixty patients with type 2 diabetes were treated with rapid-acting insulin (regular insulin) and insulin analog (insulin aspart) using the jet injector and the pen in 4 successive test cycles. Postprandial glucose and insulin concentrations in blood were measured over time. Areas under curves of glucose and the insulin were calculated, and efficacy of 2 injection methods in treatment of the diabetes was compared. Regular insulin and insulin aspart administration by the jet injector showed significant decreases in plasma glucose levels as compared to the pen injection (P < 0.05). Postprandial plasma glucose excursions at the time points of 0.5 to 3 hours were obviously lower in the jet-treated patients than the pen-treated ones (P < 0.05). Postprandial plasma insulin levels were markedly higher in the jet-treated patients than the pen-treated ones (P < 0.05). Area under the glucose curve in the pen-treated patients was significantly increased as compared to the jet-treated ones (P < 0.01). Efficacy of the insulin jet injector in treatment of type 2 diabetic patients is obviously superior to the insulin pen in regulating plasma glucose and insulin levels. PMID:28072690

  2. Impact of estrus expression and conceptus presence on plasma and uterine glucose concentrations up until maternal recognition of pregnancy in beef cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glucose is an essential component of uterine luminal fluid (ULF), it is a major energy source utilized by the conceptus for growth and development. Previously we reported increased concentrations of glucose in the ULF of cows that exhibited estrus, and observed differences in glucose transporter tr...

  3. Stimulation of phosphoenolpyruvate carboxykinase (guanosine triphosphate) activity by low concentrations of circulating glucose in perfused rat liver.

    PubMed Central

    Moreno, F J; Sánchez-Urrutia, L; Medina, J M; Sánchez-Medina, F; Mayor, F

    1975-01-01

    1. After nicotinic acid treatment, rat liver glycogen is depleted and phosphoenolpyruvate carboxykinase activity increased, to about twice the initial value. 2. The increase in phosphoenolpyruvate carboxykinase activity promoted by nicotinic acid is prevented by cycloheximide or actinomycin D, suggesting that this effect is produced by synthesis of the enzyme de novo. 3. Despite the enhancement of phosphoenolpyruvate carboxykinase activity and glycogen depletion, which occurs 5h after the injection of nicotinic acid, the gluconeogenic capacity of liver is low and considerably less than the values found in rats starved for 48h. 4. When the livers of well-fed rats are perfused in the presence of low concentrations of glucose, the activity of phosphoenolpyruvate carboxykinase significantly increases compared with the control. 5. This increase is not related to the glycogen content, but seems to be also the result of synthesis of the enzyme de novo, since this effect is counteracted by previous treatment with cycloheximide or actinomycin D. 6. Phosphoenolpyruvate carboxykinase activity is not increased in the presence of low concentrations of circulating glucose when 40 mM-imidazole (an activator of phosphodiesterase) is added to the perfusion medium. 7. Addition of dibutyryl cyclic AMP to the perfusion medium results in an increase in phosphoenolpyruvate carboxykinase activity, in spite of the presence of normal concentrations of circulating glucose. On the other hand, the concentration of cyclic AMP in the liver increases when that of glucose in the medium is low. 8. These results suggest that, in the absence of hormonal factors, the regulation of phosphoenolpyruvate carboxykinase can be accomplished by glucose itself, inadequate concentrations of it resulting in the induction of the enzyme. The mediator in this regulation, as in hormonal regulation, seems to be cyclic AMP. PMID:173301

  4. Neural network incorporating meal information improves accuracy of short-time prediction of glucose concentration.

    PubMed

    Zecchin, Chiara; Facchinetti, Andrea; Sparacino, Giovanni; De Nicolao, Giuseppe; Cobelli, Claudio

    2012-06-01

    Diabetes mellitus is one of the most common chronic diseases, and a clinically important task in its management is the prevention of hypo/hyperglycemic events. This can be achieved by exploiting continuous glucose monitoring (CGM) devices and suitable short-term prediction algorithms able to infer future glycemia in real time. In the literature, several methods for short-time glucose prediction have been proposed, most of which do not exploit information on meals, and use past CGM readings only. In this paper, we propose an algorithm for short-time glucose prediction using past CGM sensor readings and information on carbohydrate intake. The predictor combines a neural network (NN) model and a first-order polynomial extrapolation algorithm, used in parallel to describe, respectively, the nonlinear and the linear components of glucose dynamics. Information on the glucose rate of appearance after a meal is described by a previously published physiological model. The method is assessed on 20 simulated datasets and on 9 real Abbott FreeStyle Navigator datasets, and its performance is successfully compared with that of a recently proposed NN glucose predictor. Results suggest that exploiting meal information improves the accuracy of short-time glucose prediction.

  5. 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.

  6. 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.

  7. Intranasal insulin suppresses endogenous glucose production in humans compared with placebo in the presence of similar venous insulin concentrations.

    PubMed

    Dash, Satya; Xiao, Changting; Morgantini, Cecilia; Koulajian, Khajag; Lewis, Gary F

    2015-03-01

    Intranasal insulin (INI) has been shown to modulate food intake and food-related activity in the central nervous system in humans. Because INI increases insulin concentration in the cerebrospinal fluid, these effects have been postulated to be mediated via insulin action in the brain, although peripheral effects of insulin cannot be excluded. INI has been shown to lower plasma glucose in some studies, but whether it regulates endogenous glucose production (EGP) is not known. To assess the role of INI in the regulation of EGP, eight healthy men were studied in a single-blind, crossover study with two randomized visits (one with 40 IU INI and the other with intranasal placebo [INP] administration) 4 weeks apart. EGP was assessed under conditions of an arterial pancreatic clamp, with a primed, constant infusion of deuterated glucose and infusion of 20% dextrose as required to maintain euglycemia. Between 180 and 360 min after administration, INI significantly suppressed EGP by 35.6% compared with INP, despite similar venous insulin concentrations. In conclusion, INI lowers EGP in humans compared with INP, despite similar venous insulin concentrations. INI may therefore be of value in treating excess liver glucose production in diabetes.

  8. 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%.

  9. 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.

  10. Improved glucose metabolism following bariatric surgery is associated with increased circulating bile acid concentrations and remodeling of the gut microbiome.

    PubMed

    Kaska, Lukasz; Sledzinski, Tomasz; Chomiczewska, Agnieszka; Dettlaff-Pokora, Agnieszka; Swierczynski, Julian

    2016-10-21

    Clinical studies have indicated that circulating bile acid (BA) concentrations increase following bariatric surgery, especially following malabsorptive procedures such as Roux-en-Y gastric bypasses (RYGB). Moreover, total circulating BA concentrations in patients following RYGB are positively correlated with serum glucagon-like peptide-1 concentrations and inversely correlated with postprandial glucose concentrations. Overall, these data suggest that the increased circulating BA concentrations following bariatric surgery - independently of calorie restriction and body-weight loss - could contribute, at least in part, to improvements in insulin sensitivity, incretin hormone secretion, and postprandial glycemia, leading to the remission of type-2 diabetes (T2DM). In humans, the primary and secondary BA pool size is dependent on the rate of biosynthesis and the enterohepatic circulation of BAs, as well as on the gut microbiota, which play a crucial role in BA biotransformation. Moreover, BAs and gut microbiota are closely integrated and affect each other. Thus, the alterations in bile flow that result from anatomical changes caused by bariatric surgery and changes in gut microbiome may influence circulating BA concentrations and could subsequently contribute to T2DM remission following RYGB. Research data coming largely from animal and cell culture models suggest that BAs can contribute, via nuclear farnezoid X receptor (FXR) and membrane G-protein-receptor (TGR-5), to beneficial effects on glucose metabolism. It is therefore likely that FXR, TGR-5, and BAs play a similar role in glucose metabolism following bariatric surgery in humans. The objective of this review is to discuss in detail the results of published studies that show how bariatric surgery affects glucose metabolism and subsequently T2DM remission.

  11. Effects of intravenous infusion of amino acids and glucose on the yield and concentration of milk protein in dairy cows.

    PubMed

    Kim, C H; Kim, T G; Choung, J J; Chamberlain, D G

    2001-02-01

    To test the hypothesis that the availability of glucose or its precursors can influence the response of milk protein concentration to the intravenous infusion of amino acids, five cows were used in a 5 x 5 Latin square design with period lengths of 7 d. The five treatments were the basal diet of grass silage ad lib. plus 5 kg/d of a cereal-based supplement containing feather meal (Basal); Basal plus 4 g/d histidine, 8 g/d methionine and 26 g/d lysine (4H); Basal plus 8 g/d histidine, 8 g/d methionine and 26 g/d lysine (SH); and these two amino acid mixtures together with 600 g/d of gluctose (4HG and 8HG respectively). Earlier experiments with this basal diet had shown that histidine was first-limiting for secretion of milk protein, followed by methionine and lysine. The yield of milk protein was increased progressively with the amount of histidine infused. The efficiency of transfer of histidine into milk protein was 0.42 for the 4H and 4HG and 0.35 for the 8H and 8HG treatments, and the concentration of milk protein was increased over Basal by all infusion treatments. However, milk protein concentrations were higher, and lactose concentrations in the milk were lower, in the absence of added glucose. Concentrations of insulin in blood plasma were not affected by treatment. It is concluded that, with the treatments without added glucose, a shortage of glucose prevented an increase in lactose secretion, and hence limited the increase in milk yield, leading to an increased concentration of protein in the milk.

  12. Improved glucose metabolism following bariatric surgery is associated with increased circulating bile acid concentrations and remodeling of the gut microbiome

    PubMed Central

    Kaska, Lukasz; Sledzinski, Tomasz; Chomiczewska, Agnieszka; Dettlaff-Pokora, Agnieszka; Swierczynski, Julian

    2016-01-01

    Clinical studies have indicated that circulating bile acid (BA) concentrations increase following bariatric surgery, especially following malabsorptive procedures such as Roux-en-Y gastric bypasses (RYGB). Moreover, total circulating BA concentrations in patients following RYGB are positively correlated with serum glucagon-like peptide-1 concentrations and inversely correlated with postprandial glucose concentrations. Overall, these data suggest that the increased circulating BA concentrations following bariatric surgery - independently of calorie restriction and body-weight loss - could contribute, at least in part, to improvements in insulin sensitivity, incretin hormone secretion, and postprandial glycemia, leading to the remission of type-2 diabetes (T2DM). In humans, the primary and secondary BA pool size is dependent on the rate of biosynthesis and the enterohepatic circulation of BAs, as well as on the gut microbiota, which play a crucial role in BA biotransformation. Moreover, BAs and gut microbiota are closely integrated and affect each other. Thus, the alterations in bile flow that result from anatomical changes caused by bariatric surgery and changes in gut microbiome may influence circulating BA concentrations and could subsequently contribute to T2DM remission following RYGB. Research data coming largely from animal and cell culture models suggest that BAs can contribute, via nuclear farnezoid X receptor (FXR) and membrane G-protein-receptor (TGR-5), to beneficial effects on glucose metabolism. It is therefore likely that FXR, TGR-5, and BAs play a similar role in glucose metabolism following bariatric surgery in humans. The objective of this review is to discuss in detail the results of published studies that show how bariatric surgery affects glucose metabolism and subsequently T2DM remission. PMID:27818587

  13. 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.

  14. 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.

  15. 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)

  16. Assessment of circulating betatrophin concentrations in lean glucose-tolerant women with polycystic ovary syndrome.

    PubMed

    Erol, Onur; Özel, Mustafa Kemal; Ellidağ, Hamit Yaşar; Toptaş, Tayfun; Derbent, Aysel Uysal; Yılmaz, Necat

    2017-03-20

    The aims of the current study were to investigate the betatrophin levels in lean glucose-tolerant women with polycystic ovary syndrome (PCOS), and to explore the relationships between these levels and antropometric, hormonal and metabolic parameters. The study population consisted of 50 lean (body mass index [BMI] < 25 kg/m(2)) women diagnosed with PCOS using the Rotterdam criteria, and 60 age- and BMI-matched healthy controls without any features of clinical or biochemical hyperandrogenism. Before recruitment, glucose tolerance was evaluated in all of the subjects using the 2-h 75 g oral glucose-tolerance test, and only those exhibiting normal glucose tolerance were enrolled. Serum betatrophin levels were significantly higher in women with PCOS (median 322.3; range 44.7-1989.3 ng/L) compared to the controls (median 199.9; range 6.2-1912.9 ng/L; p = .005). In the control group, no significant correlation was evident between betatrophin levels and clinical or biochemical parameters. In the PCOS group, betatrophin levels were positively correlated with prolactin levels (r = .286, p = .046) and negatively correlated with BMI (r = -.283, p = .049), waist/hip ratio (r = -.324, p = .023), and low-density lipoprotein cholesterol levels (r = -.385, p = .006). Impact statement What is already known on this subject: Several studies have suggested that primary alteration in beta-cell function is a pathophysiological feature of PCOS, and insulin resistance is the most significant predictor of beta-cell dysfunction independent of obesity. Betatrophin is a circulating protein that is primarily expressed in the liver in humans. Early experimental investigations demonstrated that overexpression of betatrophin significantly promoted pancreatic beta-cell proliferation, insulin production and improved glucose tolerance. Few studies have investigated the association between PCOS and betatrophin. However, in contrast to our study, the

  17. 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.

  18. On-line near infrared bioreactor monitoring of cell density and concentrations of glucose and lactate during insect cell cultivation.

    PubMed

    Qiu, Jiang; Arnold, Mark A; Murhammer, David W

    2014-03-10

    Near infrared spectroscopy is demonstrated as a suitable method for monitoring real time cell density and concentrations of glucose and lactate during insect cell cultivation. The utility of this approach is illustrated during the cultivation of Trichoplusia ni BTI-Tn-5B1-4 insect cells in a stirred-tank bioreactor. On-line near infrared measurements are made by passing unaltered culture medium through an autoclavable near infrared flow-through sample cell during the cultivation process. Single-beam near infrared spectra were collected over the combination spectral range (5000-4000cm(-1)) through a 1.5mm path length sample. Cell density calibration model was established by uni-variable linear regressions with measured mean absorbance values of on-line spectra collected during a cultivation run. Calibration models are generated for glucose and lactate by regression analysis of both off line and on line spectra collected during a series of pre-measurement cultivation runs. Analyte-specific calibration models are generated by using a combination of spectra from both natural, unaltered samples and samples spiked with known levels of glucose and lactate. Spiked samples are used to destroy concentration correlations between solutes, thereby enhancing the selectivity of the calibration models. Absorbance spectra are used to build partial least squares calibration models for glucose and lactate. The calibration model for cell density corresponds to a univariate linear regression calibration model based on the mean absorbance between 4750 and 4250cm(-1). The standard errors of prediction are 1.54mM, 0.83mM, and 0.38×10(6)cells/mL for the glucose, lactate, and cell density models, respectively.

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

    PubMed

    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

    2013-06-28

    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 mm(3)-to qualify the sensor chip as key component in a continuous glucose monitor for the interstitial tissue.

  20. 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.

  1. Consumption of meat is associated with higher fasting glucose and insulin concentrations regardless of glucose and insulin genetic risk scores: a meta-analysis of 50,345 Caucasians12

    PubMed Central

    Fretts, Amanda M; Follis, Jack L; Nettleton, Jennifer A; Lemaitre, Rozenn N; Ngwa, Julius S; Wojczynski, Mary K; Kalafati, Ioanna Panagiota; Varga, Tibor V; Frazier-Wood, Alexis C; Houston, Denise K; Lahti, Jari; Ericson, Ulrika; van den Hooven, Edith H; Mikkilä, Vera; Kiefte-de Jong, Jessica C; Mozaffarian, Dariush; Rice, Kenneth; Renström, Frida; North, Kari E; McKeown, Nicola M; Feitosa, Mary F; Kanoni, Stavroula; Smith, Caren E; Garcia, Melissa E; Tiainen, Anna-Maija; Sonestedt, Emily; Manichaikul, Ani; van Rooij, Frank JA; Dimitriou, Maria; Raitakari, Olli; Pankow, James S; Djoussé, Luc; Province, Michael A; Hu, Frank B; Lai, Chao-Qiang; Keller, Margaux F; Perälä, Mia-Maria; Rotter, Jerome I; Hofman, Albert; Graff, Misa; Kähönen, Mika; Mukamal, Kenneth; Johansson, Ingegerd; Ordovas, Jose M; Liu, Yongmei; Männistö, Satu; Uitterlinden, André G; Deloukas, Panos; Seppälä, Ilkka; Psaty, Bruce M; Cupples, L Adrienne; Borecki, Ingrid B; Franks, Paul W; Arnett, Donna K; Nalls, Mike A; Eriksson, Johan G; Orho-Melander, Marju; Franco, Oscar H; Lehtimäki, Terho; Dedoussis, George V; Meigs, James B; Siscovick, David S

    2015-01-01

    Background: Recent studies suggest that meat intake is associated with diabetes-related phenotypes. However, whether the associations of meat intake and glucose and insulin homeostasis are modified by genes related to glucose and insulin is unknown. Objective: We investigated the associations of meat intake and the interaction of meat with genotype on fasting glucose and insulin concentrations in Caucasians free of diabetes mellitus. Design: Fourteen studies that are part of the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium participated in the analysis. Data were provided for up to 50,345 participants. Using linear regression within studies and a fixed-effects meta-analysis across studies, we examined 1) the associations of processed meat and unprocessed red meat intake with fasting glucose and insulin concentrations; and 2) the interactions of processed meat and unprocessed red meat with genetic risk score related to fasting glucose or insulin resistance on fasting glucose and insulin concentrations. Results: Processed meat was associated with higher fasting glucose, and unprocessed red meat was associated with both higher fasting glucose and fasting insulin concentrations after adjustment for potential confounders [not including body mass index (BMI)]. For every additional 50-g serving of processed meat per day, fasting glucose was 0.021 mmol/L (95% CI: 0.011, 0.030 mmol/L) higher. Every additional 100-g serving of unprocessed red meat per day was associated with a 0.037-mmol/L (95% CI: 0.023, 0.051-mmol/L) higher fasting glucose concentration and a 0.049–ln-pmol/L (95% CI: 0.035, 0.063–ln-pmol/L) higher fasting insulin concentration. After additional adjustment for BMI, observed associations were attenuated and no longer statistically significant. The association of processed meat and fasting insulin did not reach statistical significance after correction for multiple comparisons. Observed associations were not modified by genetic

  2. Plasma concentrations of cortisol, testosterone, glucose and blood gases in male goats during anaesthesia with pentobarbitone sodium.

    PubMed

    Sanhouri, A A; Jones, R S; Dobson, H

    1990-01-01

    Fasting for 24 h had no statistically significant effect on cortisol, glucose or testosterone concentrations. A dose of pentobarbitone sodium which induced light anaesthesia resulted in an immediate decrease in cortisol values from 5.0-11.1 ng/ml to 2.2-3.6 ng/ml until waking-this latter event was accompanied by an excessive release of cortisol (up to 16.6 ng/ml). In two out of three goats testosterone concentrations decreased from 4.0-9.0 ng/ml to less than 0.5 ng/ml after pentobarbitone; low values were maintained for 4.5-6 hours. Glucose concentrations were unaffected. Precise doses of pentobarbitone (20 mg/kg or 30 mg/kg) resulted in similar cortisol profiles as above but with higher concentrations achieved upon waking from the higher dose of pentobarbitone. On two out of nine occasions increased PCO2 values were recorded concurrently with increased cortisol concentrations during the period of anaesthesia, suggesting that a sufficiently strong stressful stimulus can break through the pentobarbitone blockade.

  3. Neuroscience of glucose homeostasis.

    PubMed

    La Fleur, S E; Fliers, E; Kalsbeek, A

    2014-01-01

    Plasma glucose concentrations are homeostatically regulated and maintained within strict boundaries. Several mechanisms are in place to increase glucose output when glucose levels in the circulation drop as a result of glucose utilization, or to decrease glucose output and increase tissue glucose uptake to prevent hyperglycemia. Although the term homeostasis mostly refers to stable levels, the blood glucose concentrations fluctuate over the day/night cycle, with the highest concentrations occurring just prior to the activity period in anticipation of increased caloric need. In this chapter we describe how the brain, particularly the hypothalamus, is involved in both the daily rhythm of plasma glucose concentrations and acute glucose challenges.

  4. 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.

  5. Engineering of a Novel Saccharomyces cerevisiae Wine Strain with a Respiratory Phenotype at High External Glucose Concentrations

    PubMed Central

    Henricsson, C.; de Jesus Ferreira, M. C.; Hedfalk, K.; Elbing, K.; Larsson, C.; Bill, R. M.; Norbeck, J.; Hohmann, S.; Gustafsson, L.

    2005-01-01

    The recently described respiratory strain Saccharomyces cerevisiae KOY.TM6*P is, to our knowledge, the only reported strain of S. cerevisiae which completely redirects the flux of glucose from ethanol fermentation to respiration, even at high external glucose concentrations (27). In the KOY.TM6*P strain, portions of the genes encoding the predominant hexose transporter proteins, Hxt1 and Hxt7, were fused within the regions encoding transmembrane (TM) domain 6. The resulting chimeric gene, TM6*, encoded a chimera composed of the amino-terminal half of Hxt1 and the carboxy-terminal half of Hxt7. It was subsequently integrated into the genome of an hxt null strain. In this study, we have demonstrated the transferability of this respiratory phenotype to the V5 hxt1-7Δ strain, a derivative of a strain used in enology. We also show by using this mutant that it is not necessary to transform a complete hxt null strain with the TM6* construct to obtain a non-ethanol-producing phenotype. The resulting V5.TM6*P strain, obtained by transformation of the V5 hxt1-7Δ strain with the TM6* chimeric gene, produced only minor amounts of ethanol when cultured on external glucose concentrations as high as 5%. Despite the fact that glucose flux was reduced to 30% in the V5.TM6*P strain compared with that of its parental strain, the V5.TM6*P strain produced biomass at a specific rate as high as 85% that of the V5 wild-type strain. Even more relevant for the potential use of such a strain for the production of heterologous proteins and also of low-alcohol beverages is the observation that the biomass yield increased 50% with the mutant compared to its parental strain. PMID:16204537

  6. Engineering of a novel Saccharomyces cerevisiae wine strain with a respiratory phenotype at high external glucose concentrations.

    PubMed

    Henricsson, C; de Jesus Ferreira, M C; Hedfalk, K; Elbing, K; Larsson, C; Bill, R M; Norbeck, J; Hohmann, S; Gustafsson, L

    2005-10-01

    The recently described respiratory strain Saccharomyces cerevisiae KOY.TM6*P is, to our knowledge, the only reported strain of S. cerevisiae which completely redirects the flux of glucose from ethanol fermentation to respiration, even at high external glucose concentrations (27). In the KOY.TM6*P strain, portions of the genes encoding the predominant hexose transporter proteins, Hxt1 and Hxt7, were fused within the regions encoding transmembrane (TM) domain 6. The resulting chimeric gene, TM6*, encoded a chimera composed of the amino-terminal half of Hxt1 and the carboxy-terminal half of Hxt7. It was subsequently integrated into the genome of an hxt null strain. In this study, we have demonstrated the transferability of this respiratory phenotype to the V5 hxt1-7Delta strain, a derivative of a strain used in enology. We also show by using this mutant that it is not necessary to transform a complete hxt null strain with the TM6* construct to obtain a non-ethanol-producing phenotype. The resulting V5.TM6*P strain, obtained by transformation of the V5 hxt1-7Delta strain with the TM6* chimeric gene, produced only minor amounts of ethanol when cultured on external glucose concentrations as high as 5%. Despite the fact that glucose flux was reduced to 30% in the V5.TM6*P strain compared with that of its parental strain, the V5.TM6*P strain produced biomass at a specific rate as high as 85% that of the V5 wild-type strain. Even more relevant for the potential use of such a strain for the production of heterologous proteins and also of low-alcohol beverages is the observation that the biomass yield increased 50% with the mutant compared to its parental strain.

  7. Dapagliflozin‐lowered blood glucose reduces respiratory Pseudomonas aeruginosa infection in diabetic mice

    PubMed Central

    Åstrand, Annika; Wingren, Cecilia; Benjamin, Audra; Tregoning, John S; Garnett, James P; Groves, Helen; Gill, Simren; Orogo‐Wenn, Maria; Lundqvist, Anders J; Walters, Dafydd; Smith, David M; Taylor, John D; Baker, Emma H

    2017-01-01

    Background and Purpose Hyperglycaemia increases glucose concentrations in airway surface liquid and increases the risk of pulmonary Pseudomonas aeruginosa infection. We determined whether reduction of blood and airway glucose concentrations by the anti‐diabetic drug dapagliflozin could reduce P. aeruginosa growth/survival in the lungs of diabetic mice. Experimental Approach The effect of dapagliflozin on blood and airway glucose concentration, the inflammatory response and infection were investigated in C57BL/6J (wild type, WT) or leptin receptor‐deficient (db/db) mice, treated orally with dapagliflozin prior to intranasal dosing with LPS or inoculation with P. aeruginosa. Pulmonary glucose transport and fluid absorption were investigated in Wistar rats using the perfused fluid‐filled lung technique. Key Results Fasting blood, airway glucose and lactate concentrations were elevated in the db/db mouse lung. LPS challenge increased inflammatory cells in bronchoalveolar lavage fluid from WT and db/db mice with and without dapagliflozin treatment. P. aeruginosa colony‐forming units (CFU) were increased in db/db lungs. Pretreatment with dapagliflozin reduced blood and bronchoalveolar lavage glucose concentrations and P. aeruginosa CFU in db/db mice towards those seen in WT. Dapagliflozin had no adverse effects on the inflammatory response in the mouse or pulmonary glucose transport or fluid absorption in the rat lung. Conclusion and Implications Pharmacological lowering of blood glucose with dapagliflozin effectively reduced P. aeruginosa infection in the lungs of diabetic mice and had no adverse pulmonary effects in the rat. Dapagliflozin has potential to reduce the use, or augment the effect, of antimicrobials in the prevention or treatment of pulmonary infection. PMID:28192604

  8. 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

    2016-01-06

    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.

  9. 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

  10. Effects of dietary D-psicose on diurnal variation in plasma glucose and insulin concentrations of rats.

    PubMed

    Matsuo, Tatsuhiro; Izumori, Ken

    2006-09-01

    The effects of supplemental D-psicose in the diet on diurnal variation in plasma glucose and insulin concentrations were investigated in rats. Forty-eight male Wistar rats were divided into four groups. Each group except for the control group was fed a diet of 5% D-fructose, D-psicose, or psico-rare sugar (3:1 mixture of D-fructose and D-psicose) for 8 weeks. Plasma glucose levels were lower and plasma insulin levels were higher at all times of day in the psicose and psico-rare sugar groups than in the control and fructose groups. Weight gain was significantly lower in the psicose group than in the control and fructose groups. Liver glycogen content, both before and after meals was higher in the psicose group than in the control and fructose groups. These results suggest that supplemental D-psicose can lower plasma glucose levels and reduce body fat accumulation. Hence, D-psicose might be useful in preventing postprandial hyperglycemia in diabetic patients.

  11. 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.

  12. African plant foods rich in non-starch polysaccharides reduce postprandial blood glucose and insulin concentrations in healthy human subjects.

    PubMed

    Onyechi, U A; Judd, P A; Ellis, P R

    1998-11-01

    The effects of two vegetable flours, prepared from the African plants Detarium senegalense Gmelin, a legume, and Cissus rotundifolia, a shrub, on postprandial blood glucose and insulin concentrations in human subjects, were investigated. Chemical analysis indicated that these flours contained significant amounts of NSP. The detarium in particular was found to be a rich source of water-soluble NSP (SNSP). The flours were incorporated into two types of breakfast meal, a stew meal and a wheat bread meal, containing 50 g and 70 g available carbohydrate respectively. Both meals also contained 10-12 g NSP, the major fraction of which was SNSP. Control and fibre-rich meals were consumed on separate days in randomized order by two different groups of subjects (n 5, stew meals; n 10, bread meals). Venous blood samples were taken at fasting (0 min) and postprandially at 30 min intervals for 2.5 h and the plasma analysed for glucose and insulin. Compared with the controls, detarium and cissus meals elicited significant reductions (P < 0.006) in plasma glucose levels at most postprandial time points and for area-under-the-curve (AUC) values (AUC reductions 38-62%). Significant reductions (P < 0.002) in plasma insulin levels at various postprandial time points and for AUC values were also seen after detarium and cissus breads (AUC reductions 43 and 36% respectively), but not after the fibre-rich stew meals. SNSP and starch are possibly the main, but not the only, components responsible for the glucose- and insulin-lowering effects of cissus flour. The main SNSP fraction of detarium, identified as a high-molecular-weight xyloglucan, is likely to be a primary factor in determining the physiological activity of detarium flour.

  13. 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.

  14. Chronic Exposure to Excess Nutrients Left-shifts the Concentration Dependence of Glucose-stimulated Insulin Secretion in Pancreatic β-Cells.

    PubMed

    Erion, Karel A; Berdan, Charles A; Burritt, Nathan E; Corkey, Barbara E; Deeney, Jude T

    2015-06-26

    Hyperinsulinemia (HI) is elevated plasma insulin at basal glucose. Impaired glucose tolerance is associated with HI, although the exact cause and effect relationship remains poorly defined. We tested the hypothesis that HI can result from an intrinsic response of the β-cell to chronic exposure to excess nutrients, involving a shift in the concentration dependence of glucose-stimulated insulin secretion. INS-1 (832/13) cells were cultured in either a physiological (4 mm) or high (11 mm) glucose concentration with or without concomitant exposure to oleate. Isolated rat islets were also cultured with or without oleate. A clear hypersensitivity to submaximal glucose concentrations was evident in INS-1 cells cultured in excess nutrients such that the 25% of maximal (S0.25) glucose-stimulated insulin secretion was significantly reduced in cells cultured in 11 mm glucose (S0.25 = 3.5 mm) and 4 mm glucose with oleate (S0.25 = 4.5 mm) compared with 4 mm glucose alone (S0.25 = 5.7 mm). The magnitude of the left shift was linearly correlated with intracellular lipid stores in INS-1 cells (r(2) = 0.97). We observed no significant differences in the dose responses for glucose stimulation of respiration, NAD(P)H autofluorescence, or Ca(2+) responses between left- and right-shifted β-cells. However, a left shift in the sensitivity of exocytosis to Ca(2+) was documented in permeabilized INS-1 cells cultured in 11 versus 4 mm glucose (S0.25 = 1.1 and 1.7 μm, respectively). Our results suggest that the sensitivity of exocytosis to triggering is modulated by a lipid component, the levels of which are influenced by the culture nutrient environment.

  15. The protective activity of Urtica dioica leaves on blood glucose concentration and beta-cells in streptozotocin-diabetic rats.

    PubMed

    Golalipour, Mohammad Jafar; Khori, Vahid

    2007-04-15

    This study was done to determine the protective activity of the hydroalcholic extract of Urtica dioica leaves on Hyperglycemia and beta-cells in hyperglycemic rats. Thirty Wistar rats were allocated in groups of normal, Diabetic and treatment. Hyperglycemia in Rats induced by 80 mg kg(-1) streptozotocin. In treatment group, animals received hydroalcholic extract of Urtica dioica 100 mg kg(-1) day(-1) for five days, intraperitoneally and then hyperglycemia induced by streptozotocin. The blood glucose concentration was measured by using a Glucometer in 1st, 3rd and 5th weeks. In the end of 5th weeks the animals in each group were sacrificed by anesthesia and whole pancreas in three groups extracted and fixed in bouin's fluid and stained by chromealum hematoxiline-phloxine and beta cells were counted in three groups by Olympus microscope. Mean +/- SE of blood glucose concentrations in the end of fifth weeks were 99.4 +/-5.0, 454.7 +/- 34.5 and 303.6 +/- 100.6 in control, diabetic and treatment groups, respectively (p < 0.05). The percentages of beta-cells in control, diabetic and treatment groups were 73.6, 1.9 and 22.9%, respectively. The percentage of beta-cells in treatment group comparing with diabetic group was significant (p < 0.05). This study showed that the protective administration of hydroalcholic extract of Urtica dioica has hypoglycemic effect and protective activity of beta-cells of langerhans in hyperglycemic rats.

  16. Low Concentrations of Metformin Suppress Glucose Production in Hepatocytes through AMP-activated Protein Kinase (AMPK)*♦

    PubMed Central

    Cao, Jia; Meng, Shumei; Chang, Evan; Beckwith-Fickas, Katherine; Xiong, Lishou; Cole, Robert N.; Radovick, Sally; Wondisford, Fredric E.; He, Ling

    2014-01-01

    Metformin is a first-line antidiabetic agent taken by 150 million people across the world every year, yet its mechanism remains only partially understood and controversial. It was proposed that suppression of glucose production in hepatocytes by metformin is AMPK-independent; however, unachievably high concentrations of metformin were employed in these studies. In the current study, we find that metformin, via an AMP-activated protein kinase (AMPK)-dependent mechanism, suppresses glucose production and gluconeogenic gene expression in primary hepatocytes at concentrations found in the portal vein of animals (60–80 μm). Metformin also inhibits gluconeogenic gene expression in the liver of mice administered orally with metformin. Furthermore, the cAMP-PKA pathway negatively regulates AMPK activity through phosphorylation at Ser-485/497 on the α subunit, which in turn reduces net phosphorylation at Thr-172. Because diabetic patients often have hyperglucagonemia, AMPKα phosphorylation at Ser-485/497 is a therapeutic target to improve metformin efficacy. PMID:24928508

  17. 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

  18. Increased fetal insulin concentrations for one week fail to improve insulin secretion or β-cell mass in fetal sheep with chronically reduced glucose supply.

    PubMed

    Lavezzi, Jinny R; Thorn, Stephanie R; O'Meara, Meghan C; LoTurco, Dan; Brown, Laura D; Hay, William W; Rozance, Paul J

    2013-01-01

    Maternal undernutrition during pregnancy and placental insufficiency are characterized by impaired development of fetal pancreatic β-cells. Prolonged reduced glucose supply to the fetus is a feature of both. It is unknown if reduced glucose supply, independent of other complications of maternal undernutrition and placental insufficiency, would cause similar β-cell defects. Therefore, we measured fetal insulin secretion and β-cell mass following prolonged reduced fetal glucose supply in sheep. We also tested whether restoring physiological insulin concentrations would correct any β-cell defects. Pregnant sheep received either a direct saline infusion (CON = control, n = 5) or an insulin infusion (HG = hypoglycemic, n = 5) for 8 wk in late gestation (75 to 134 days) to decrease maternal glucose concentrations and reduce fetal glucose supply. A separate group of HG fetuses also received a direct fetal insulin infusion for the final week of the study with a dextrose infusion to prevent a further fall in glucose concentration [hypoglycemic + insulin (HG+I), n = 4]. Maximum glucose-stimulated insulin concentrations were 45% lower in HG fetuses compared with CON fetuses. β-Cell, pancreatic, and fetal mass were 50%, 37%, and 40% lower in HG compared with CON fetuses, respectively (P < 0.05). Insulin secretion and β-cell mass did not improve in the HG+I fetuses. These results indicate that chronically reduced fetal glucose supply is sufficient to reduce pancreatic insulin secretion in response to glucose, primarily due to reduced pancreatic and β-cell mass, and is not correctable with insulin.

  19. Longitudinal association between fasting blood glucose concentrations and first stroke in hypertensive adults in China: effect of folic acid intervention.

    PubMed

    Xu, Richard B; Kong, Xiangyi; Xu, Benjamin P; Song, Yun; Ji, Meng; Zhao, Min; Huang, Xiao; Li, Ping; Cheng, Xiaoshu; Chen, Fang; Zhang, Yan; Tang, Genfu; Qin, Xianhui; Wang, Binyan; Hou, Fan Fan; Dong, Qiang; Chen, Yundai; Yang, Tianlun; Sun, Ningling; Li, Xiaoying; Zhao, Lianyou; Ge, Junbo; Ji, Linong; Huo, Yong; Li, Jianping

    2017-03-01

    Background: Diabetes is a known risk factor for stroke, but data on its prospective association with first stroke are limited. Folic acid supplementation has been shown to protect against first stroke, but its role in preventing first stroke in diabetes is unknown.Objectives: This post hoc analysis of the China Stroke Primary Prevention Trial tested the hypotheses that the fasting blood glucose (FBG) concentration is positively associated with first stroke risk and that folic acid treatment can reduce stroke risk associated with elevated fasting glucose concentrations.Design: This analysis included 20,327 hypertensive adults without a history of stroke or myocardial infarction, who were randomly assigned to a double-blind daily treatment with 10 mg enalapril and 0.8 mg folic acid (n = 10,160) or 10 mg enalapril alone (n = 10,167). Kaplan-Meier survival analysis and Cox proportionate hazard models were used to test the hypotheses with adjustment for pertinent covariables.Results: During a median treatment duration of 4.5 y, 616 participants developed a first stroke (497 ischemic strokes). A high FBG concentration (≥7.0 mmol/L) or diabetes, compared with a low FBG concentration (<5.0 mmol/L), was associated with an increased risk of first stroke (6.0% compared with 2.6%, respectively; HR: 1.9; 95% CI: 1.3, 2.8; P < 0.001). Folic acid treatment reduced the risk of stroke across a wide range of FBG concentrations ≥5.0 mmol/L, but risk reduction was greatest in subjects with FBG concentrations ≥7.0 mmol/L or with diabetes (HR: 0.66; 95% CI: 0.46, 0.97; P < 0.05). There was a significant interactive effect of FBG and folic acid treatment on first stroke (P = 0.01).Conclusions: In Chinese hypertensive adults, an FBG concentration ≥7.0 mmol/L or diabetes is associated with an increased risk of first stroke; this increased risk is reduced by 34% with folic acid treatment. These findings warrant additional investigation. This trial was registered at clinicaltrials

  20. How does airway exposure of aflatoxin B1 affect serum albumin adduct concentrations? Evidence based on epidemiological study and animal experimentation.

    PubMed

    Mo, Xianwei; Lai, Hao; Yang, Yang; Xiao, Jun; He, Ke; Liu, Chao; Chen, Jiansi; Lin, Yuan

    2014-08-01

    Aflatoxin B1 (AFB1) airway inhalation represents an additional route of exposure to this toxin. However, the association between AFB1 inhalation and serum AFB1 albumin adducts remains unclear. The aim of this study was to explore the association between airway exposure to AFB1 and serum AFB1 albumin adduct concentrations via an epidemiological study, as well as in an AFB1 airway exposure animal model. Our epidemiological study was conducted in a sugar factory in the Guangxi Autonomous Region of China. In order to examine fungal contamination, air samples were obtained in the workshop and areas outside the workshop, such as the office and nearby store. Dust samples were also collected from the bagasse warehouse and presser workshop, and were analyzed using an indirect competitive enzyme-linked immunosorbent assay (ELISA). Additionally, blood samples were collected from a total of 121 workshop workers, and a control group (n = 80) was comprised of workers who undertook administrative tasks or other work outside the workshop. The animal experiment was conducted in the laboratory animal center of Guangxi Medical University, where a total of 60 adult male rabbits were involved in this study. By intubation, AFB1 was administered in three groups of rabbits daily, at dose rates of 0.075, 0.05 and 0.025 mg/kg/day for a period of 7 days. Blood samples were collected on day 1, day 3, day 7 and day 21, and the measurements of the AFB1 albumin adducts in the serum were performed by a double antibody sandwich ELISA. The epidemiological study showed that serum albumin adducts were detected in 67 workshop workers (55.37%), and the values ranged 6.4 pg/mg albumin to 212 pg/mg albumin (mean value: 51 ± 4.62 pg/mg albumin). In contrast, serum albumin adducts were detected in only 7 control group participants, with the values ranging from 9 pg AFB1/mg albumin to 59 pg/mg albumin (mean value: 20 ± 13.72 pg/mg albumin). The animal experiment revealed that the rabbits had detectable

  1. 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.

  2. Magnesium oxide nanoparticles coated with glucose can silence important genes of Leishmania major at sub-toxic concentrations.

    PubMed

    Bafghi, Ali Fatahi; Daghighi, Mojtaba; Daliri, Karim; Jebali, Ali

    2015-12-01

    The aim of this study was to investigate the effect of magnesium oxide nanoparticles (MgO NPs) and MgO NPs coated with glucose (MONPCG) on Leishmania (L) major. First, the promastigotes of L. major were separately incubated with serial concentrations of MgO NPs and MONPCG for 24, 48, and 72 h at 37 °C. Then, the cell viability of promastigotes was evaluated by MTT assay. On the other hand, the relative expression of Cpb and GP63 genes was detected by quantitative-real time PCR. Based on results, the increase of concentration, both MgO NPs and MONPCG, and incubation time led to decrease of cell viability. Moreover, the expression of Cpb and GP63 genes was decreased with increase of concentration of MgO NPs and MONPCG. Also, the increase of incubation time led to decrease of their expression in MgO NPs treated promastogotes. But, in case of MONPCG treated promastogotes, the increase of incubation time did not change the expression of Cpb and GP63. Interestingly, MONPCG could silence Cpb and GP63 genes better than MgO NPs. Note, the capability was also seen at sub-toxic concentrations of MONPCG.

  3. Basal blood glucose concentration in free-living striped mice is influenced by food availability, ambient temperature and social tactic.

    PubMed

    Schradin, Carsten; Pillay, Neville; Kondratyeva, Anna; Yuen, Chi-Hang; Schoepf, Ivana; Krackow, Sven

    2015-05-01

    Vertebrates obtain most of their energy through food, which they store mainly as body fat or glycogen, with glucose being the main energy source circulating in the blood. Basal blood glucose concentration (bBGC) is expected to remain in a narrow homeostatic range. We studied the extent to which bBGC in free-living African striped mice (Rhabdomys pumilio) is influenced by ecological factors with a bearing on energy regulation, i.e. food availability, abiotic environmental variation and social tactic. Striped mice typically form extended family groups that huddle together at night, reducing energetic costs of thermoregulation, but solitary individuals also occur in the population. We analysed 2827 blood samples from 1008 individuals of seven different social categories that experienced considerable variation in food supply and abiotic condition. Blood samples were taken from mice in the morning after the overnight fast and before foraging. bBGC increased significantly with food plant abundance and decreased significantly with minimum daily ambient temperature. Solitary striped mice had significantly higher bBGC than group-living striped mice. Our results suggest that adaptive responses of bBGC occur and we found large natural variation, indicating that bBGC spans a far greater homeostatic range than previously thought.

  4. Prognostic value of admission blood glucose concentration and diabetes diagnosis on survival after acute myocardial infarction: results from 4702 index cases in routine practice.

    PubMed

    Squire, Ian B; Nelson, Christopher P; Ng, Leong L; Jones, David R; Woods, Kent L; Lambert, Paul C

    2010-04-01

    The diagnosis of diabetes and admission blood glucose concentration are associated with adverse outcome after acute coronary syndromes. We compared the relative association with survival after ST elevation AMI (acute myocardial infarction) of admission blood glucose concentration and of diabetes diagnosis. We carried out a retrospective cohort study in 4702 consecutive patients with STEMI (ST elevation AMI) occurring from 1 April 1993 to 31 December 2005, assessed for mortality at 30 days and 1 year. Patients were classified according to antecedent diabetes and by blood glucose concentration at admission (quartile 1, <7 mmol/l; quartile 2, 7–8.2 mmol/l;quartile 3, 8.3–10.9 mmol/l; quartile 4, 11 mmol/l). Multivariable models were constructed for determinants of mortality, including year of STEMI and demographic variables, entering blood glucose concentration and antecedent diabetes individually and together. All-cause 30-day and 1-year mortality were 22.8% and 31.3% for patients with antecedent diabetes, compared with 16.3% and 23.0% respectively for those without. For glucose quartiles 1, 2, 3 and 4, crude 30-day mortality was 9.0%, 10.6%, 17.9% and 31.0%. Adjusted 30-day mortality risk was similar in quartile 2, higher by >80% in quartile 3 and by >150% in quartile 4, compared with glucose quartile 1. Antecedent diabetes was associated with an increase in mortality [unadjusted odds ratio (OR)1.52 (95% CI 1.24, 1.86)]. On multivariable analysis (excluding glucose quartile), this reduced to 1.24 (0.98, 1.58) and changed to a small, statistically non-significant reduction in risk when glucose quartile was added to the analysis [adjusted OR 0.87 (0.67, 1.13)]. Inclusion of antecedent diabetes in multivariable models did not add to the predictive value for mortality of glucose quartile(P=0.368). Similar relationships were observed for 1 year mortality. In patients with STEMI, blood glucose concentration shows graded association with risk of 30-day and 1-year

  5. The Phillips airway.

    PubMed

    Haridas, R P; Wilkinson, D J

    2012-07-01

    The Phillips airway was developed by George Ramsay Phillips. There is no known original description of the airway and the earliest known reference to it is from 1919. The airway and its modifications are described.

  6. Sorbitol promotes growth of Zymomonas mobilis in environments with high concentrations of sugar: evidence for a physiological function of glucose-fructose oxidoreductase in osmoprotection.

    PubMed Central

    Loos, H; Krämer, R; Sahm, H; Sprenger, G A

    1994-01-01

    The gram-negative ethanologenic bacterium Zymomonas mobilis is able to grow in media containing high concentrations of glucose or other sugars. A novel compatible solute for bacteria, sorbitol, which enhances growth of Z. mobilis at glucose concentrations exceeding 0.83 M (15%), is described. Added sorbitol was accumulated intracellularly up to 1 M to counteract high external glucose concentrations (up to 1.66 M or 30%). Accumulation of sorbitol was triggered by a glucose upshift (e.g., from 0.33 to 1.27 M or 6 to 23%) and was prevented by the uncoupler CCCP (carbonyl cyanide m-chlorophenylhydrazone; 100 microM). The sorbitol transport system followed Michaelis-Menten kinetics, with an apparent Km of 34 mM and a Vmax of 11.2 nmol.min-1.mg-1 (dry mass). Sorbitol was produced by the cells themselves and was accumulated when growing on sucrose (1 M or 36%) by the action of the periplasmic enzyme glucose-fructose oxidoreductase, which converts glucose and fructose to gluconolactone and sorbitol. Thus, Z. mobilis can form and accumulate the compatible solute sorbitol from a natural carbon source, sucrose, in order to overcome osmotic stress in high-sugar media. No other major compatible solute (betaine, proline, glutamate, or trehalose) was detected. PMID:8002594

  7. Blockage of upper airway

    MedlinePlus

    ... Airway obstruction - acute upper Images Throat anatomy Choking Respiratory system References Cukor J, Manno M. Pediatric respiratory emergencies: upper airway obstruction and infections. In: Marx ...

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. Staphylococcus aureus Alpha-Toxin Mediates General and Cell Type-Specific Changes in Metabolite Concentrations of Immortalized Human Airway Epithelial Cells

    PubMed Central

    Gierok, Philipp; Harms, Manuela; Richter, Erik; Hildebrandt, Jan-Peter; Lalk, Michael; Mostertz, Jörg; Hochgräfe, Falko

    2014-01-01

    Staphylococcus aureus alpha-toxin (Hla) is a potent pore-forming cytotoxin that plays an important role in the pathogenesis of S. aureus infections, including pneumonia. The impact of Hla on the dynamics of the metabolome in eukaryotic host cells has not been investigated comprehensively. Using 1H-NMR, GC-MS and HPLC-MS, we quantified the concentrations of 51 intracellular metabolites and assessed alterations in the amount of 25 extracellular metabolites in the two human bronchial epithelial cell lines S9 and 16HBE14o− under standard culture conditions and after treatment with sub-lethal amounts (2 µg/ml) of recombinant Hla (rHla) in a time-dependent manner. Treatment of cells with rHla caused substantial decreases in the concentrations of intracellular metabolites from different metabolic pathways in both cell lines, including ATP and amino acids. Concomitant increases in the extracellular concentrations were detected for various intracellular compounds, including nucleotides, glutathione disulfide and NAD+. Our results indicate that rHla has a major impact on the metabolome of eukaryotic cells as a consequence of direct rHla-mediated alterations in plasma membrane permeability or indirect effects mediated by cellular signalling. However, cell-specific changes also were observed. Glucose consumption and lactate production rates suggest that the glycolytic activity of S9 cells, but not of 16HBE14o− cells, is increased in response to rHla. This could contribute to the observed higher level of resistance of S9 cells against rHla-induced membrane damage. PMID:24733556

  13. 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.

  14. Dietary intake and serum and hair concentrations of minerals and their relationship with serum lipids and glucose levels in hypertensive and obese patients with insulin resistance.

    PubMed

    Suliburska, Joanna; Bogdański, Paweł; Pupek-Musialik, Danuta; Krejpcio, Zbigniew

    2011-02-01

    Inadequate minerals intake, as well as disruption of some metabolic processes in which microelements are cofactors, are suggested to lead to the development of hypertension. The role of minerals in the pathogenesis of hypertension still remains to be explained. In the present study, we sought to determine associations between serum and hair mineral concentrations and serum lipids and glucose levels. Forty obese hypertensive subjects with insulin resistance and 40 healthy volunteers were recruited in the study. Blood pressure, BMI, and insulin resistance were recorded in all subjects. Levels of lipids, glucose, sodium and potassium, iron, copper, zinc, magnesium, and calcium were assessed in serum. Iron, copper, zinc, magnesium, and calcium were assessed in hair. Dietary intake of the analyzed minerals was estimated. We found distinctly higher concentrations of serum iron and serum and hair calcium as well as markedly lower levels of hair zinc in the hypertensive subjects. The study group manifested also significantly lower daily intake of calcium, magnesium, and iron. We observed a relationship between the concentrations of iron, zinc, and copper in serum and hair and high and low range of cholesterol, triglycerides, and glucose serum levels in the studied patients. Moreover, this study demonstrated significant correlation between serum and hair concentrations of selected minerals and their dietary intake and levels of serum lipids and glucose and blood pressure in the study and the control groups. The obtained results seem to indicate the association between lipid and glucose metabolism and iron, copper, zinc, and calcium concentrations in blood and hair of hypertensive and obese patients with insulin resistance.

  15. Triggers of airway inflammation.

    PubMed

    Kerrebijn, K F

    1986-01-01

    Most asthmatics have hyperresponsive airways. This makes them more sensitive than non-asthmatics to bronchoconstricting environmental exposures which, in their turn, may enhance responsiveness. Airway inflammation is considered to be a key determinant of airway hyperresponsiveness: the fact that chronic airway inflammation in cystic fibrosis does not lead to airway hyperresponsiveness of any importance indicates, however, that the role of airway inflammation is complex and incompletely elucidated. The main inducers of airway inflammation are viral infections, antigens, occupational stimuli and pollutants. Although exercise, airway cooling and hyper- or hypotonic aerosols are potent stimuli of bronchoconstriction, it is questionable if airway inflammation is involved in their mode of action. Each of the above-mentioned stimuli is discussed, with emphasis laid on the relation of symptoms to mechanisms.

  16. Physiologically based pharmacokinetic-pharmacodynamic modeling to predict concentrations and actions of sodium-dependent glucose transporter 2 inhibitor canagliflozin in human intestines and renal tubules.

    PubMed

    Mori, Kazumi; Saito, Ryuta; Nakamaru, Yoshinobu; Shimizu, Makiko; Yamazaki, Hiroshi

    2016-11-01

    Canagliflozin is a recently developed sodium-glucose cotransporter (SGLT) 2 inhibitor that promotes renal glucose excretion and is considered to inhibit renal SGLT2 from the luminal side of proximal tubules. Canagliflozin reportedly inhibits SGLT1 weakly and suppresses postprandial plasma glucose, suggesting that it also inhibits intestinal SGLT1. However, it is difficult to measure the drug concentrations of these assumed sites of action directly. The pharmacokinetic-pharmacodynamic (PK/PD) relationships of canagliflozin remain poorly characterized. Therefore, a physiologically based pharmacokinetic (PBPK) model of canagliflozin was developed based on clinical data from healthy volunteers and it was used to simulate luminal concentrations in intestines and renal tubules. In small intestine simulations, the inhibition ratios for SGLT1 were predicted to be 40%-60% after the oral administration of clinical doses (100-300 mg/day). In contrast, inhibition ratios of canagliflozin for renal SGLT2 and SGLT1 were predicted to be approximately 100% and 0.2%-0.4%, respectively. These analyses suggest that canagliflozin only inhibits SGLT2 in the kidney. Using the simulated proximal tubule luminal concentrations of canagliflozin, the urinary glucose excretion rates in canagliflozin-treated diabetic patients were accurately predicted using the renal glucose reabsorption model as a PD model. Because the simulation of canagliflozin pharmacokinetics was successful, this PBPK methodology was further validated by successfully simulating the pharmacokinetics of dapagliflozin, another SGLT2 inhibitor. The present results suggest the utility of this PBPK/PD model for predicting canagliflozin concentrations at target sites and help to elucidate the pharmacological effects of SGLT1/2 inhibition in humans. Copyright © 2016 John Wiley & Sons, Ltd.

  17. The Saccharomyces cerevisiae Hot1p regulated gene YHR087W (HGI1) has a role in translation upon high glucose concentration stress

    PubMed Central

    2012-01-01

    Background While growing in natural environments yeasts can be affected by osmotic stress provoked by high glucose concentrations. The response to this adverse condition requires the HOG pathway and involves transcriptional and posttranscriptional mechanisms initiated by the phosphorylation of this protein, its translocation to the nucleus and activation of transcription factors. One of the genes induced to respond to this injury is YHR087W. It encodes for a protein structurally similar to the N-terminal region of human SBDS whose expression is also induced under other forms of stress and whose deletion determines growth defects at high glucose concentrations. Results In this work we show that YHR087W expression is regulated by several transcription factors depending on the particular stress condition, and Hot1p is particularly relevant for the induction at high glucose concentrations. In this situation, Hot1p, together to Sko1p, binds to YHR087W promoter in a Hog1p-dependent manner. Several evidences obtained indicate Yhr087wp’s role in translation. Firstly, and according to TAP purification experiments, it interacts with proteins involved in translation initiation. Besides, its deletion mutant shows growth defects in the presence of translation inhibitors and displays a slightly slower translation recovery after applying high glucose stress than the wild type strain. Analyses of the association of mRNAs to polysome fractions reveals a lower translation in the mutant strain of the mRNAs corresponding to genes GPD1, HSP78 and HSP104. Conclusions The data demonstrates that expression of Yhr087wp under high glucose concentration is controlled by Hot1p and Sko1p transcription factors, which bind to its promoter. Yhr087wp has a role in translation, maybe in the control of the synthesis of several stress response proteins, which could explain the lower levels of some of these proteins found in previous proteomic analyses and the growth defects of the deletion strain

  18. Insulin resistance and glucose and lipid concentrations in a cohort of perinatally HIV-infected Latin American children.

    PubMed

    Hazra, Rohan; Hance, Laura Freimanis; Monteiro, Jacqueline Pontes; Ruz, Noris Pavia; Machado, Daisy Maria; Saavedra, Mariza; Motta, Fabrizio; Harris, D Robert

    2013-07-01

    We measured glucose, insulin and lipids in 249 perinatally HIV-infected Latin American children. Only 1 subject had impaired fasting glucose; 6.8% had insulin resistance. Abnormalities in total, low-density lipoprotein and high-density lipoprotein cholesterol and triglycerides were reported for 13%, 13%, 21% and 34%, respectively. Continued follow-up of this population is necessary to characterize the evolution and clinical consequences of these findings.

  19. 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.

  20. Glucose concentration and medium volume influence cell viability and glycosaminoglycan synthesis in chondrocyte-seeded alginate constructs.

    PubMed

    Heywood, Hannah K; Bader, Dan L; Lee, David A

    2006-12-01

    Increasing the thickness of tissue-engineered cartilage is associated with loss of chondrocyte viability and biosynthetic activity at the tissue center. Exceptionally high volumes of culture medium, however, can maintain cellularity and glycosaminoglycan synthesis throughout 4-mm-thick constructs. We hypothesized that glucose supplementation could replicate the augmentation of tissue formation achieved by medium volume. Chondrocyte-alginate constructs (40x10(6) cells/mL) were cultured for 14 days in 0.4-6.4 mL/10(-6) cells of either low- (5.1 mM) or high- (20.4 mM) glucose medium. Glucose was critical to chondrocyte viability, and glucose uptake increased significantly (P < .001) with both medium volume and glucose supplementation. After 14 days, constructs cultured in 0.4 mL/10(-6) cells of low-glucose medium had a mass of 172 +/- 6.1 mg and glycosaminoglycan (GAG) content of 0.32 +/- 0.03 mg (mean +/- standard deviation). A 4-fold increase in medium volume increased the final construct mass by 44% and GAG content by 207%. An equivalent increase in glucose supply in the absence of volume change increased these parameters by just 10% and 73%, respectively. A similar trend was observed from 0.8 to 3.2 mL/10(-6) cells, when maximal values of construct GAG content and mass were obtained. Therefore, medium volume remains an important consideration for the optimal culture of tissue-engineered cartilage.

  1. The concentration of cyclic AMP and the activity of cyclic AMP dependent protein kinase and an inhibitor in the adipose tissue of rats fed lard or glucose diets.

    PubMed

    Jackowski, M M; Tepperman, H M; Tepperman, J

    1978-08-01

    Measurements of tissue cyclic AMP (cAMP) concentration, the activity of cAMP-dependent protein kinase and the level of the enzyme's thermostable, macromolecular inhibitor were made on preparations of rat epididymal fat pad from animals fed high fat or high carbohydrate diets. The cAMP concentration from rats adapted to a high lard diet for 14-15 days was 153 +/- 17.8 pmoles/mg protein as opposed to 76 +/- 6.0 found with high glucose diet. No significant difference in total cAMP-dependent protein kinase activity was observed among rats fed high glucose, high lard or laboratory chow, although the enzyme's activity ratio (-cAMP)(+cAMP) was significantly elevated with lard feeding (0.49 +/- 0.02) as opposed to glucose feeding (0.43 +/- 0.01). Crude preparations from lard and glucose fed animals were equivalent in inhibitory activity when tested with enzyme from chow fed animals. Agarose column chromatography separated holoenzyme and C subunit forms of the protein kinase when 500 mM NaCl was present in the elution buffer. Absence of the salt allowed subunit reassociation to occur. Direct addition of NaCl greater than or equal to 75 mM significantly inhibited protein kinase activity. The results indicate that the adipose tissue of rats fed a high lard diet has a higher concentration of cAMP and an increased protein kinase activity ratio than tissue from rats fed a fat free, high glucose diet. Total cAMP-dependent protein kinase activity and the level of a thermostable macromolecular inhibitor remained unchanged.

  2. Emergency airway puncture

    MedlinePlus

    ... support for only a very short period of time. Alternative Names Needle cricothyrotomy Images Emergency airway puncture Cricoid cartilage Emergency airway puncture - series References Hebert RB, Bose S, Mace SE. Cricothyrotomy and ...

  3. Upper airway biopsy

    MedlinePlus

    ... upper airway Images Upper airway test Bronchoscopy Throat anatomy References Yung RC, Boss EF. Tracheobronchial endoscopy. In: Flint PW, Haughey BH, Lund LJ, et al, eds. Cummings Otolaryngology: Head & Neck Surgery. 5th ed. Philadelphia, PA: Elsevier Mosby; ...

  4. Evaluation of the Sensitivity and Specificity of Use of Glucose and pH for Bacterial Screening of Platelet Concentrates Compared to the Bact/Alert.

    PubMed

    Razjou, Farhad; Naghadeh, Hossein Timori; Ferdowsi, Shirin; Dabirmoghadam, Abolfazl

    2017-03-01

    Bacterial contamination of blood components is the major infectious risk in transfusion medicine. Since platelets should be stored at room temperature that makes them an excellent growth medium for bacteria; it is mentioned as a major problem in transfusion medicine. Transfusion risk of a bacterial contaminated platelet concentrate is higher than viral pathogen such as HIV, HBV, HCV and HTLV. The objective of this study was to evaluation of the sensitivity and specificity of use of glucose and pH for bacterial screening of platelet concentrates compared to the Bact/Alert. 1332 platelet concentrates were screened by the Bact/Alert system for aerobic and anaerobic bacterial contamination. Bacterial contamination was also evaluated by using urine reagent strips (Multistix10 SG Bayer) and culture methods. Moreover PH screening with a pH meter (Metrohm 744 Swiss) and glucose was also used for detection of bacterial contamination. The rate of bacterial contamination detected by the Bact/Alert system in platelet concentrates was 25 in 1332 (1.9 %). It contained 15 (1.1 %) for aerobic bacteria and 10 (.8 %) for anaerobic bacteria. 226 of 1332 were considered as containing bacteria by using urine reagent strips. Six of the 226 units were also positive by the Bact/Alert system. Three of those units were culture positive for aerobic bacteria and three for anaerobic. The result of platelet concentrates that underwent pH screening by use of pH meter and a pH portion of urine reagent strips was the same. The sensitivity and specificity of considering glucose alone for detection of bacterial contamination were 12 and 98 % respectively. For pH alone, these were 24 and 83 %. For glucose and/or pH, these were 24 and 83 %; and for combination of glucose and pH, these were 12 and 98 %. Our results showed use of glucose/pH strips would improve the safety of blood products and should be encouraged.

  5. Careers in Airway Science.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC.

    The Federal Aviation Administration (FAA) has initiated the Airway Science curriculum as a method of preparing the next generation of aviation technicians and managers. This document: (1) discusses the FAA's role in the Airway Science program; (2) describes some of the career fields that FAA offers to Airway Science graduates (air traffic control…

  6. 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).

  7. Resolution of 8-aminonaphthalene-1,3,6-trisulfonic acid-labeled glucose oligomers in polyacrylamide gel electrophoresis at low gel concentration.

    PubMed

    Cabanes-Macheteau, Marion; Chrambach, Andreas; Taverna, Myriam; Buzás, Zsuzsanna; Berna, Patrick

    2004-01-01

    A discontinuous Tris-Cl/acetate (OAc) buffer system, unprecedently containing OAc as the trailing constituent, and operative in polyacrylamide gel electrophoresis (PAGE) at low polyacrylamide concentration (T = 4.8%) is described in the paper. The characteristics of the electrophoretic system are illustrated by the resolution of fluorescent 8-aminonaphthalene-1,3,6-trisulfonic acid (ANTS)-labeled malto-oligosaccharides and dextran homopolymers. In this buffer system, the resolving phase is constituted by Tris-OAc behind a moving boundary formed between the leading chloride ion of Tris-HCl gel buffer and the trailing OAc ion provided by a catholyte of NH(4)OAc. In contrast with the results obtained with Tris-CI/glycinate buffer commonly used in electrophoresis, or with Tris-CI/borate, the best resolution of the glucose oligomers containing 1-4 glucose units in Tris-OAc, pH 8.8, ionic strength of 0.08, was obtained at 4.8% polyacrylamide concentration, using 0.5 M NH(4)OAc, pH 9.5 as the catholyte. Under those conditions, the ANTS-glucose oligomers were separated with mobilities decreasing from glucose to maltohexaose. The linear Ferguson plots (log relative mobility, R(f), vs.%T) of the glucose oligomers show that the surface net charge of those oligomers is inversely related to their sizes, given by the slopes, K(R), of the plots. The molecular weight of the oligomers is directly but nonlinearly related to K(R). The novel electrophoretic system illustrated here for separation of short ANTS-saccharides can be potentially applied to the resolution of other biomolecules such as rapidly migrating DNA, peptides or proteins.

  8. 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.

  9. 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.

  10. 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

  11. 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.

    PubMed

    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

  12. 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

  13. Stimulatory short-term effects of free fatty acids on glucagon secretion at low to normal glucose concentrations.

    PubMed

    Bollheimer, L Cornelius; Landauer, Heike C; Troll, Stephanie; Schweimer, Joachim; Wrede, Christian E; Schölmerich, Jürgen; Buettner, Roland

    2004-11-01

    While free fatty acids (FFA) are well known as insulin secretagogues, their effects on pancreatic alpha cells have been mostly neglected. In the present study we therefore systematically analyzed the glucagon metabolism of rat pancreatic islets under the influence of FFA. Primary islets were incubated in the presence or absence of 200 micromol/L albumin-complexed palmitate or oleate at 2.8 mmol/L versus 16.7 mmol/L glucose and glucagon secretion was monitored over 8 hours. In addition to these time-course experiments, dose dependency of palmitate-induced effects was tested by a 2-hour incubation with 50 to 300 micromol/L albumin-complexed palmitate at 2.8 mmol/L and 5.6 mmol/L glucose. Apart from glucagon secretion, intracellular immunoreactive glucagon and cellular preproglucagon-mRNA (PPG-mRNA) content were determined from the remaining cell lysates. FFA, especially palmitate, induced a significant and dose-dependent increase of glucagon secretion (in average 2-fold above control) during the first 120 minutes of incubation at low to normal glucose (2.8 and 5.6 mmol/L). There was no significant glucagonotropic effect of FFA at concomitant 16.7 mmol/L glucose. Intracellular glucagon as well as cellular PPG-mRNA content were found to be dose-dependently diminished by palmitate when compared with untreated controls at 5.6 mmol/L glucose. The present analysis therefore points to a new role for FFA as a nutritient secretagogue and a modulator of alpha-cellular glucagon metabolism.

  14. 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.

  15. 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

  16. Glucose repression of lactose/galactose metabolism in Kluyveromyces lactis is determined by the concentration of the transcriptional activator LAC9 (K1GAL4) [corrected

    PubMed Central

    Zachariae, W; Kuger, P; Breunig, K D

    1993-01-01

    In the budding yeast Kluyveromyces lactis glucose repression of genes involved in lactose and galactose metabolism is primarily mediated by LAC9 (or K1GAL4) the homologue of the well-known Saccharomyces cerevisiae transcriptional activator GAL4. Phenotypic difference in glucose repression existing between natural strains are due to differences in the LAC9 gene (Breunig, 1989, Mol.Gen.Genet. 261, 422-427). Comparison between the LAC9 alleles of repressible and non-repressible strains revealed that the phenotype is a result of differences in LAC9 gene expression. A two-basepair alteration in the LAC9 promoter region produces a promoter-down effect resulting in slightly reduced LAC9 protein levels under all growth conditions tested. In glucose/galactose medium any change in LAC9 expression drastically affects expression of LAC9 controlled genes e.g. those encoding beta-galactosidase or galactokinase revealing a strong dependence of the kinetics of induction on the LAC9 concentration. We propose that in tightly repressible strains the activator concentration drops below a critical threshold that is required for induction to occur. A model is presented to explain how small differences in activator levels are amplified to produce big changes in expression levels of metabolic genes. Images PMID:8441621

  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. Identification of genes required for maximal tolerance to high-glucose concentrations, as those present in industrial alcoholic fermentation media, through a chemogenomics approach.

    PubMed

    Teixeira, Miguel C; Raposo, Luís R; Palma, Margarida; Sá-Correia, Isabel

    2010-04-01

    Chemogenomics, the study of genomic responses to chemical compounds, has the potential to elucidate the basis of cellular resistance to those chemicals. This knowledge can be applied to improve the performance of strains of industrial interest. In this study, a collection of approximately 5,000 haploid single deletion mutants of Saccharomyces cerevisiae in which each nonessential yeast gene was individually deleted, was screened for strains with increased susceptibility toward stress induced by high-glucose concentration (30% w/v), one of the main stresses occurring during industrial alcoholic fermentation processes aiming the production of alcoholic beverages or bio-ethanol. Forty-four determinants of resistance to high-glucose stress were identified. The most significant Gene Ontology (GO) terms enriched in this dataset are vacuolar organization, late endosome to vacuole transport, and regulation of transcription. Clustering the identified resistance determinants by their known physical and genetic interactions further highlighted the importance of nutrient metabolism control in this context. A concentration of 30% (w/v) of glucose was found to perturb vacuolar function, by reducing cell ability to maintain the physiological acidification of the vacuolar lumen. This stress also affects the active rate of proton efflux through the plasma membrane. Based on results of published studies, the present work revealed shared determinants of yeast resistance to high-glucose and ethanol stresses, including genes involved in vacuolar function, cell wall biogenesis (ANP1), and in the transcriptional control of nutrient metabolism (GCN4 and GCR1), with possible impact on the design of more robust strains to be used in industrial alcoholic fermentation processes.

  19. Associations between meal size, gastric emptying and post-prandial plasma glucose, insulin and lactate concentrations in meal-fed cats.

    PubMed

    Coradini, M; Rand, J S; Filippich, L J; Morton, J M; O'Leary, C A

    2015-08-01

    Plasma glucose and insulin concentrations are increased for 12-24 h in healthy cats following moderate- to high-carbohydrate meals. This study investigated associations between gastric emptying time and post-prandial plasma glucose, insulin and lactate concentrations in cats fed an extruded dry, high-carbohydrate, moderate-fat, low-protein diet (51, 28, 21% metabolizable energy, respectively) once daily by varying meal volume. Eleven healthy, non-obese, neutered adult cats were enrolled in a prospective study and fed to maintain body weight. Ultrasound examinations were performed for up to 26 h, and blood collections over 24 h after eating meals containing approximately 100% and 50% of the cats' daily caloric intake (209 and 105 kJ/kg BW, respectively). Gastric emptying time was increased after a meal of 209 kJ/kg BW compared with 105 kJ/kg BW (median gastric emptying times 24 and 14 h, respectively; p = 0.03). Time for glucose to return to fasting was longer after the 209 kJ/kg BW meal (median 20 h; 25th and 75th percentiles 15 and 23 h, respectively) than the 105 kJ/kg BW meal (13, 12 and 14 h; p < 0.01); however, peak glucose was not higher after the 209 kJ/kg BW meal compared with the 105 kJ/kg BW meal [(mean ± SD) 6.6 ± 0.6 and 7.8 ± 1.2 mmol/l, respectively, p = 0.07]. Times for insulin to return to fasting were not significantly longer after the 209 kJ/kg BW meal than the 105 kJ/kg BW meal (p = 0.29). d- and l-lactate concentrations were not associated with gastric emptying time or post-prandial blood glucose and insulin. Based on results obtained, prolonged gastric emptying contributes to prolonged post-prandial hyperglycemia in cats meal fed a high-carbohydrate, low-protein, dry diet and fasting times for cats' meal-fed diets of similar composition should be 14-26 h, depending on meal size.

  20. Effect of Acarbose, Sitagliptin and combination therapy on blood glucose, insulin, and incretin hormone concentrations in experimentally induced postprandial hyperglycemia of healthy cats.

    PubMed

    Mori, Akihiro; Ueda, Kaori; Lee, Peter; Oda, Hitomi; Ishioka, Katsumi; Arai, Toshiro; Sako, Toshinori

    2016-06-01

    Acarbose (AC) and Sitagliptin (STGP) are oral hypoglycemic agents currently used either alone or in conjunction with human diabetic (Type 2) patients. AC has been used with diabetic cats, but not STGP thus far. Therefore, the objective of this study was to determine the potential use of AC or STGP alone and in combination for diabetic cats, by observing their effect on short-term post-prandial serum glucose, insulin, and incretin hormone (active glucagon-like peptide-1 (GLP-1) and total glucose dependent insulinotropic polypeptide (GIP)) concentrations in five healthy cats, following ingestion of a meal with maltose. All treatments tended (p<0.10; 5-7.5% reduction) to reduce postprandial glucose area under the curve (AUC), with an accompanying significant reduction (p<0.05, 35-45%) in postprandial insulin AUC as compared to no treatment. Meanwhile, a significant increase (p<0.05) in postprandial active GLP-1 AUC was observed with STGP (100% higher) and combined treatment (130% greater), as compared to either AC or no treatment. Lastly, a significant reduction (p<0.05) in postprandial total GIP AUC was observed with STGP (21% reduction) and combined treatment (7% reduction) as compared to control. Overall, AC, STGP, or combined treatment can significantly induce positive post-prandial changes to insulin and incretin hormone levels of healthy cats. Increasing active GLP-1 and reducing postprandial hyperglycemia appear to be the principal mechanisms of combined treatment. Considering the different, but complementary mechanisms of action by which AC and STGP induce lower glucose and insulin levels, combination therapy with both these agents offers great potential for treating diabetic cats in the future.

  1. Hydrogen concentration in expired air analyzed with a new hydrogen sensor, plasma glucose rise, and symptoms of lactose intolerance after oral administration of 100 gram lactose.

    PubMed

    Berg, A; Eriksson, M; Bárány, F; Einarsson, K; Sundgren, H; Nylander, C; Lundström, I; Blomstrand, R

    1985-09-01

    A rapid breath hydrogen analyzer to detect lactose malabsorption is described. After ingestion of a lactose solution the patient expires into a mouthpiece attached to a hydrogen sensor at 30-min intervals for 3 1/2 h. The hydrogen of the expired air causes a voltage change that can be transformed into ppm from a calibration curve. A tolerance test with a load of 100 g lactose was performed in 43 consecutive patients with various gastrointestinal disturbances, referred to the laboratory for the commonly used lactose tolerance test based on plasma glucose measurements. Eleven patients developed symptoms of lactose intolerance during the test. Biopsy specimens from the distal duodenum or proximal jejunum showed partial villous atrophy in one, in whom celiac disease with lactose intolerance was diagnosed; the other 10 had normal specimens. In nine of them lactose intolerance was diagnosed and confirmed by observation for months on a lactose-poor diet. The 10th patient (H.P.L.) did not improve on such a diet. He also showed pronounced symptoms of intolerance during a test with monosaccharides (glucose + galactose). His intestinal disease remained undiagnosed. The 11 patients with symptoms of intolerance and 3 patients without symptoms during the lactose load showed a flat plasma glucose curve after drinking the lactose solution--that is, a maximum rise of the glucose concentration of 1.5 mmol/l. One of the symptom-free patients dropped out and could not be observed, another did not improve on a lactose-poor diet, and the third noticed a favorable effect of the diet on stool consistency but not on other abdominal symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Effects of dehulled adlay on plasma glucose and lipid concentrations in streptozotocin-induced diabetic rats fed a diet enriched in cholesterol.

    PubMed

    Yeh, Pao-Hua; Chiang, Wenchang; Chiang, Meng-Tsan

    2006-09-01

    Adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) is a cereal food for humans and has been also used as a superior medical herb substance and functional food for traditional treatment of diabetes in China. However, its scientific basis as a functional food is still unclear. The purpose of this study was to investigate the effect of dietary dehulled adlay on plasma lipid and glucose concentrations in diabetic rats. The diabetic male Sprague-Dawley (SD) rats, induced by injection of streptozotocin (60 mg/kg subcutaneously), were fed a cholesterol-rich diet (0.5% cholesterol) containing corn starch or dehulled adlay for four weeks. After completion of the experimental period, the abdominal adipose tissue and liver of rats were excised and weighed, and the plasma glucose, triglyceride, and lipoprotein cholesterol concentrations were assayed. The results showed that diabetic rats fed a dehulled adlay diet exhibited a greater adipose tissue weight (9.36 +/- 3.43 vs. 5.39 +/- 3.04 g, p < 0.05) and a reduced food intake (39.3 +/- 5.9 vs. 61.0 +/- 11.7 g/day, p < 0.05) when compared with animals fed a cornstarch diet. Significantly decreased plasma glucose (261.6 +/- 96.6 vs. 422.1 +/- 125.4 mg/dL, p < 0.05), total cholesterol (289.4 +/- 140.6 vs. 627.3 +/- 230.5 mg/dL, p < 0.05), and triglyceride (52.3 +/- 14.4 vs. 96.5 +/- 36.6 mg/dL, p < 0.05) levels were observed in rats fed the dehulled adlay diet. In addition, the ingestion of dehulled adlay appears to significantly decrease plasma low-density lipoprotein (LDL) plus very low-density lipoprotein (VLDL) cholesterol concentrations. Rats fed a dehulled adlay diet showed an increase in fecal weight and cholesterol contents of stools. Although a significantly decreased plasma thiobarbituric reactive substances (TBARS) value was observed in diabetic rats fed the dehulled adlay diet (6.2 +/- 3.4 vs. 11.0 +/- 3.8 nmol malondialdehyde (MDA)/mL, p < 0.05), no significant difference in the hepatic TBARS value was observed between

  3. High glucose concentration induces the overexpression of transforming growth factor-beta through the activation of a platelet-derived growth factor loop in human mesangial cells.

    PubMed Central

    Di Paolo, S.; Gesualdo, L.; Ranieri, E.; Grandaliano, G.; Schena, F. P.

    1996-01-01

    High glucose concentration has been shown to induce the overexpression of transforming growth factor (TGF)-beta 1 mRNA and protein in different cell types, including murine mesangial cells, thus possibly accounting for the expansion of mesangial extracellular matrix observed in diabetic glomerulopathy. In the present study, we evaluated platelet-derived growth factor (PDGF) B-chain and PDGF-beta receptor gene expression in human mesangial cells (HMCs) exposed to different concentrations of glucose and then sought a possible relationship between a PDGF loop and the modulation of TGF-beta 1 expression. HMC [3H]thymidine incorporation was upregulated by 30 mmol/L glucose (HG) up to 24 hours, whereas it was significantly inhibited at later time points. Neutralizing antibodies to PDGF BB abolished the biphasic response to HG, whereas anti-TGF-beta antibodies reversed only the late inhibitory effect of hyperglycemic medium. HG induced an early and persistent increase of PDGF B-chain gene expression, as evaluated by reverse transcriptase polymerase chain reaction, whereas PDGF-beta receptor mRNA increased by twofold after 6 hours, thereafter declining at levels 70% lower than in controls after 24 hours. 125I-Labeled PDGF BB binding studies in HMCs exposed to HG for 24 hours confirmed the decrease of PDGF-beta receptor expression. TGF-beta 1-specific transcripts showed 43 and 78% increases after 24 and 48 hours of incubation in HG, respectively, which was markedly diminished by anti-PDGF BB neutralizing antibodies or suramin. We conclude that HG induces an early activation of a PDGF loop that, in turn, causes an increase of TGF-beta 1 gene expression, thus modulating both HMC proliferation and mesangial matrix production. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:8952542

  4. Controversies in Pediatric Perioperative Airways

    PubMed Central

    Klučka, Jozef; Štourač, Petr; Štoudek, Roman; Ťoukálková, Michaela; Harazim, Hana; Kosinová, Martina

    2015-01-01

    Pediatric airway management is a challenge in routine anesthesia practice. Any airway-related complication due to improper procedure can have catastrophic consequences in pediatric patients. The authors reviewed the current relevant literature using the following data bases: Google Scholar, PubMed, Medline (OVID SP), and Dynamed, and the following keywords: Airway/s, Children, Pediatric, Difficult Airways, and Controversies. From a summary of the data, we identified several controversies: difficult airway prediction, difficult airway management, cuffed versus uncuffed endotracheal tubes for securing pediatric airways, rapid sequence induction (RSI), laryngeal mask versus endotracheal tube, and extubation timing. The data show that pediatric anesthesia practice in perioperative airway management is currently lacking the strong evidence-based medicine (EBM) data that is available for adult subpopulations. A number of procedural steps in airway management are derived only from adult populations. However, the objective is the same irrespective of patient age: proper securing of the airway and oxygenation of the patient. PMID:26759809

  5. Comparison of the Current Diagnostic Criterion of HbA1c with Fasting and 2-Hour Plasma Glucose Concentration

    PubMed Central

    Karnchanasorn, Rudruidee; Huang, Jean; Feng, Wei; Chuang, Lee-Ming

    2016-01-01

    To determine the effectiveness of hemoglobin A1c (HbA1c) ≥ 6.5% in diagnosing diabetes compared to fasting plasma glucose (FPG) ≥ 126 mg/dL and 2-hour plasma glucose (2hPG) ≥ 200 mg/dL in a previously undiagnosed diabetic cohort, we included 5,764 adult subjects without established diabetes for whom HbA1c, FPG, 2hPG, and BMI measurements were collected. Compared to the FPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 43.3% (106 subjects). Compared to the 2hPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 28.1% (110 subjects). Patients who were diabetic using 2hPG criterion but had HbA1c < 6.5% were more likely to be older (64 ± 15 versus 60 ± 15 years old, P = 0.01, mean ± STD), female (53.2% versus 38.2%, P = 0.008), leaner (29.7 ± 6.1 versus 33.0 ± 6.6 kg/m2, P = 0.000005), and less likely to be current smokers (18.1% versus 29.1%, P = 0.02) as compared to those with HbA1c ≥ 6.5%. The diagnostic agreement in the clinical setting revealed the current HbA1c ≥ 6.5% is less likely to detect diabetes than those defined by FPG and 2hPG. HbA1c ≥ 6.5% detects less than 50% of diabetic patients defined by FPG and less than 30% of diabetic patients defined by 2hPG. When the diagnosis of diabetes is in doubt by HbA1c, FPG and/or 2hPG should be obtained. PMID:27597979

  6. Effects of bacterial lipopolysaccharide injection on white blood cell counts, hematological variables, and serum glucose, insulin, and cortisol concentrations in ewes fed low- or high-protein diets.

    PubMed

    Yates, D T; Löest, C A; Ross, T T; Hallford, D M; Carter, B H; Limesand, S W

    2011-12-01

    Bacterial lipopolysaccharide endotoxins (LPS) elicit inflammatory responses reflective of acute bacterial infection. We determined if feeding ewes high-CP (15.5%) or low-CP (8.5%) diets for 10 d altered inflammatory responses to an intravenous bolus of 0 (control), 0.75 (L75), or 1.50 (L150) μg of LPS/kg of BW in a 2 × 3 factorial arrangement of treatments (n = 5/treatment). Rectal temperatures, heart and respiratory rates, blood leukocyte concentrations, and serum cortisol, insulin, and glucose concentrations were measured for 24 h after an LPS bolus (bolus = 0 h). In general, rectal temperatures were greater (P ≤ 0.05) in control ewes fed high CP, but LPS increased (P ≤ 0.05) rectal temperatures in a dose-dependent manner at most times between 2 and 24 h after the bolus. Peak rectal temperatures in L75 and L150 occurred 4 h after the bolus. A monophasic, dose-independent increase (P ≤ 0.023) in serum cortisol occurred from 0.5 to 24 h after the bolus, with peak cortisol at 4 h. Serum insulin was increased (P ≤ 0.016) by LPS in a dose-dependent manner from 4 to 24 h after the bolus. Insulin did not differ between control ewes fed high- and low-CP diets but was greater (P < 0.001) in L75 ewes fed low CP compared with high CP and in L150 ewes fed high CP compared with low CP. Increased insulin was not preceded by increased serum glucose. Total white blood cell concentrations were not affected (P ≥ 0.135) by LPS, but the neutrophil and monocyte fractions of white blood cells were increased (P ≤ 0.047) by LPS at 12 and 24 h and at 24 h after the bolus, respectively, and the lymphocyte fraction was increased (P = 0.037) at 2 h and decreased (P ≤ 0.006) at 12 and 24 h after the bolus. Red blood cell and hemoglobin concentrations and hematocrit (%) were increased (P ≤ 0.022) by LPS at 2 and 4 h after the bolus. Rectal temperatures and serum glucose were greater (P ≤ 0.033) in ewes fed a high-CP diet before LPS injection, but these effects were lost at

  7. The role of alpha- and beta-adrenoceptor subtypes in mediating the effects of catecholamines on fasting glucose and insulin concentrations in the rat.

    PubMed Central

    John, G. W.; Doxey, J. C.; Walter, D. S.; Reid, J. L.

    1990-01-01

    1. The role of alpha- and beta-adrenoceptor subtypes in the regulation of plasma glucose and immunoreactive insulin (IRI) levels has been investigated in normal conscious fasted rats by employing selective agonists and antagonists. 2. Adrenaline (0.2 mg kg-1)-induced hyperglycaemia was abolished by the selective alpha 2-adrenoceptor antagonist idazoxan (1.0 mg kg-1), unaltered by non-selective beta-adrenoceptor blockade (propranolol, 1.0 mg kg-1) and potentiated by the selective alpha 1-adrenoceptor antagonist prazosin (0.3 mg kg-1). Adrenaline increased plasma IRI levels in the presence of idazoxan but not in the presence of either prazosin or propranolol. 3. The selective alpha 2-adrenoceptor agonists UK 14304 (0.1 and 0.3 mg kg-1) and BHT-920 (0.2 and 0.5 mg kg-1) elicited dose-dependent hyperglycaemic responses, but did not alter plasma IRI levels. UK 14304 (0.1 mg kg-1)-evoked hyperglycaemia was blocked by idazoxan but not by prazosin. 4. The selective alpha 1-adrenoceptor agonists methoxamine (0.3 mg kg-1) and phenylephrine (0.3 mg kg-1) failed to modify either plasma glucose or IRI levels. 5. Isoprenaline (0.2 mg kg-1) elicited hyperglycaemic and insulinotropic responses which were attenuated by propranolol (1.0 mg kg-1) and the selective beta 2-adrenoceptor antagonist ICI 118551 (1.0 mg kg-1), but not by the beta 1-selective antagonists atenolol (1.0 mg kg-1) and betaxolol (1.0 mg kg-1). 6. None of the antagonists per se affected basal plasma glucose or IRI concentrations, except prazosin (1.0 mg kg-1).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1976400

  8. Leucine supplementation improves adiponectin and total cholesterol concentrations despite the lack of changes in adiposity or glucose homeostasis in rats previously exposed to a high-fat diet

    PubMed Central

    2011-01-01

    Background Studies suggest that leucine supplementation (LS) has a therapeutic potential to prevent obesity and to promote glucose homeostasis. Furthermore, regular physical exercise is a widely accepted strategy for body weight maintenance and also for the prevention of obesity. The aim of this study was to determine the effect of chronic LS alone or combined with endurance training (ET) as potential approaches for reversing the insulin resistance and obesity induced by a high-fat diet (HFD) in rats. Methods Forty-seven rats were randomly divided into two groups. Animals were fed a control diet-low fat (n = 10) or HFD (n = 37). After 15 weeks on HFD, all rats received the control diet-low fat and were randomly divided according to treatment: reference (REF), LS, ET, and LS+ET (n = 7-8 rats per group). After 6 weeks of treatment, the animals were sacrificed and body composition, fat cell volume, and serum concentrations of total cholesterol, HDL-cholesterol, triacylglycerol, glucose, adiponectin, leptin and tumor necrosis factor-alpha (TNF-α) were analyzed. Results At the end of the sixth week of treatment, there was no significant difference in body weight between the REF, LS, ET and LS+ET groups. However, ET increased lean body mass in rats (P = 0.019). In addition, ET was more effective than LS in reducing adiposity (P = 0.019), serum insulin (P = 0.022) and TNF-α (P = 0.044). Conversely, LS increased serum adiponectin (P = 0.021) levels and reduced serum total cholesterol concentration (P = 0.042). Conclusions The results showed that LS had no beneficial effects on insulin sensitivity or adiposity in previously obese rats. On the other hand, LS was effective in increasing adiponectin levels and in reducing total cholesterol concentration. PMID:21899736

  9. Growth in glucose-based medium and exposure to subinhibitory concentrations of imipenem induce biofilm formation in a multidrug-resistant clinical isolate of Acinetobacter baumannii

    PubMed Central

    2009-01-01

    Background Acinetobacter baumannii is emerging as an important nosocomial pathogen. Multidrug resistance, as well as ability to withstand environmental stresses, makes eradication of A. baumannii difficult, particularly from hospital settings. Results Over a six-year period, 73 isolates of A. baumannii were collected from infected patients in two hospitals in Italy. While 69 out of the 73 isolates displayed identical multidrug antibiotic resistance pattern, they were susceptible to carbapenems. Genetic profiles of these 69 isolates, determined by Pulsed Field Gel Electrophoresis (PFGE), indicated that they were genetically related and could be clustered in a specific clone, called SMAL. We tested the ability of the SMAL clone to form biofilm, an important determinant for bacterial colonization of the human host and for persistence in the hospital environment. Biofilm formation by A. baumannii SMAL, measured as surface adhesion to polystyrene, is strongly affected by growth conditions, being impaired in rich growth media such as LB, while being favoured in glucose-based medium. Surface adhesion in glucose-based media is inhibited by treatment with cellulase, suggesting that it depends on production of cellulose or of a chemically related extracellular polysaccharide. Exposure of A. baumannii SMAL to subinhibitory concentrations of imipenem resulted in biofilm stimulation and increased production of iron uptake proteins. Growth in iron-supplemented medium also stimulated surface adhesion, thus suggesting that increased intracellular iron concentrations might act as an environmental signal for biofilm formation in A. baumannii SMAL. Conclusions Our results indicate that exposure to subinhibitory concentrations of imipenem can stimulate biofilm formation and induce iron uptake in a pathogenic strain of A. baumannii, with potential implications on antibiotic susceptibility and ability to persist in the human host. PMID:20028528

  10. Yolk concentrations of hormones and glucose and egg weight and egg dimensions in unincubated chicken eggs, in relation to egg sex and hen body weight.

    PubMed

    Aslam, M Aamir; Hulst, Marcel; Hoving-Bolink, Rita A H; Smits, Mari A; de Vries, Bonnie; Weites, Ilse; Groothuis, Ton G G; Woelders, Henri

    2013-06-15

    Birds can manipulate offspring sex ratio under natural and experimental conditions and maternal hormones have been shown to be involved in this process. Studies also provided evidence for the presence of sex specific concentrations of yolk hormones in avian eggs. These findings led to the suggestion that yolk hormones could influence genetic sex determination in birds. However, in previous studies, yolk hormone concentrations and egg sex were studied in incubated eggs, although incubation of the eggs and embryonic development can alter yolk hormone concentrations and measured sex ratio. This study is the first to determine a wide array of egg components and hen body weight in relation to the sex of the egg in unincubated eggs. Egg parameters studied were yolk concentrations of testosterone, estradiol, androstenedione, progesterone, dihydrotestosterone, and glucose, and egg weight and dimensions. In addition, we studied the associations among all measured parameters. Associations were found between a number of yolk hormones (progesterone associated with testosterone, estradiol and androstenedione; androstenedione with testosterone; dihydrotestosterone with estradiol and androstenedione) as well as between yolk testosterone and egg length and egg weight. There were no significant overall differences between male and female chicken eggs in any of the measured egg parameters. However, there were a few interactions such as the interaction of egg sex with dihydrotestosterone and with hen body weight which predicted estradiol levels and an interaction of estradiol levels with egg width for predicting sex of egg. Their biological relevance need, however, further study.

  11. The effect of NO-donors on chloride efflux, intracellular Ca(2+) concentration and mRNA expression of CFTR and ENaC in cystic fibrosis airway epithelial cells.

    PubMed

    Oliynyk, Igor; Hussain, Rashida; Amin, Ahmad; Johannesson, Marie; Roomans, Godfried M

    2013-06-01

    Since previous studies showed that the endogenous bronchodilator, S-nitrosglutathione (GSNO), caused a marked increase in CFTR-mediated chloride (Cl(-)) efflux and improved the trafficking of CFTR to the plasma membrane, and that also the nitric oxide (NO)-donor GEA3162 had a similar, but smaller, effect on Cl(-) efflux, it was investigated whether the NO-donor properties of GSNO were relevant for its effect on Cl(-) efflux from airway epithelial cells. Hence, the effect of a number of other NO-donors, sodium nitroprusside (SNP), S-nitroso-N-acetyl-DL-penicillamine (SNAP), diethylenetriamine/nitric oxide adduct (DETA-NO), and diethylenetriamine/nitric oxide adduct (DEA-NONOate) on Cl(-) efflux from CFBE (∆F508/∆F508-CFTR) airway epithelial cells was tested. Cl(-) efflux was determined using the fluorescent N-(ethoxycarbonylmethyl)-6-methoxyquinoliniu bromide (MQAE)-technique. Possible changes in the intracellular Ca(2+) concentration were tested by the fluorescent fluo-4 method in a confocal microscope system. Like previously with GSNO, after 4 h incubation with the NO-donor, an increased Cl(-) efflux was found (in the order SNAP>DETA-NO>SNP). The effect of DEA-NONOate on Cl(-) efflux was not significant, and the compound may have (unspecific) deleterious effects on the cells. Again, as with GSNO, after a short (5 min) incubation, SNP had no significant effect on Cl(-) efflux. None of the NO-donors that had a significant effect on Cl(-) efflux caused significant changes in the intracellular Ca(2+) concentration. After 4 h preincubation, SNP caused a significant increase in the mRNA expression of CFTR. SNAP and DEA-NONOate decreased the mRNA expression of all ENaC subunits significantly. DETA-NO caused a significant decrease only in α-ENaC expression. After a short preincubation, none of the NO-donors had a significant effect, neither on the expression of CFTR, nor on that of the ENaC subunits in the presence and absence of L-cysteine. It can be concluded that

  12. Interactions between zinc transporter-8 gene (SLC30A8) and plasma zinc concentrations for impaired glucose regulation and type 2 diabetes.

    PubMed

    Shan, Zhilei; Bao, Wei; Zhang, Yan; Rong, Ying; Wang, Xia; Jin, Yilin; Song, Yadong; Yao, Ping; Sun, Changhao; Hu, Frank B; Liu, Liegang

    2014-05-01

    Although both SLC30A8 rs13266634 single nucleotide polymorphism and plasma zinc concentrations have been associated with impaired glucose regulation (IGR) and type 2 diabetes (T2D), their interactions for IGR and T2D remain unclear. Therefore, to assess zinc-SLC30A8 interactions, we performed a case-control study in 1,796 participants: 218 newly diagnosed IGR patients, 785 newly diagnosed T2D patients, and 793 individuals with normal glucose tolerance. After adjustment for age, sex, BMI, family history of diabetes, and hypertension, the multivariable odds ratio (OR) of T2D associated with a 10 µg/dL higher plasma zinc level was 0.87 (95% CI 0.85-0.90). Meanwhile, the OR of SLC30A8 rs13266634 homozygous genotypes CC compared with TT was 1.53 (1.11-2.09) for T2D. Similar associations were found in IGR and IGR&T2D groups. Each 10 µg/dL increment of plasma zinc was associated with 22% (OR 0.78 [0.72-0.85]) lower odds of T2D in TT genotype carriers, 17% (0.83 [0.80-0.87]) lower odds in CT genotype carriers, and 7% (0.93 [0.90-0.97]) lower odds in CC genotype carriers (P for interaction = 0.01). Our study suggested that the C allele of rs13266634 was associated with higher odds of T2D, and higher plasma zinc was associated with lower odds. The inverse association of plasma zinc concentrations with T2D was modified by SLC30A8 rs13266634. Further studies are warranted to confirm our findings and clarify the mechanisms underlying the interaction between plasma zinc and the SLC30A8 gene in relation to T2D.

  13. Evolutionary engineering of a glycerol-3-phosphate dehydrogenase-negative, acetate-reducing Saccharomyces cerevisiae strain enables anaerobic growth at high glucose concentrations.

    PubMed

    Guadalupe-Medina, Víctor; Metz, Benjamin; Oud, Bart; van Der Graaf, Charlotte M; Mans, Robert; Pronk, Jack T; van Maris, Antonius J A

    2014-01-01

    Glycerol production by Saccharomyces cerevisiae, which is required for redox-cofactor balancing in anaerobic cultures, causes yield reduction in industrial bioethanol production. Recently, glycerol formation in anaerobic S. cerevisiae cultures was eliminated by expressing Escherichia coli (acetylating) acetaldehyde dehydrogenase (encoded by mhpF) and simultaneously deleting the GPD1 and GPD2 genes encoding glycerol-3-phosphate dehydrogenase, thus coupling NADH reoxidation to reduction of acetate to ethanol. Gpd⁻ strains are, however, sensitive to high sugar concentrations, which complicates industrial implementation of this metabolic engineering concept. In this study, laboratory evolution was used to improve osmotolerance of a Gpd⁻ mhpF-expressing S. cerevisiae strain. Serial batch cultivation at increasing osmotic pressure enabled isolation of an evolved strain that grew anaerobically at 1 M glucose, at a specific growth rate of 0.12 h⁻¹. The evolved strain produced glycerol at low concentrations (0.64 ± 0.33 g l⁻¹). However, these glycerol concentrations were below 10% of those observed with a Gpd⁺ reference strain. Consequently, the ethanol yield on sugar increased from 79% of the theoretical maximum in the reference strain to 92% for the evolved strains. Genetic analysis indicated that osmotolerance under aerobic conditions required a single dominant chromosomal mutation, and one further mutation in the plasmid-borne mhpF gene for anaerobic growth.

  14. A glucose sensor protein for continuous glucose monitoring.

    PubMed

    Veetil, Jithesh V; Jin, Sha; Ye, Kaiming

    2010-12-15

    In vivo continuous glucose monitoring has posed a significant challenge to glucose sensor development due to the lack of reliable techniques that are non- or at least minimally-invasive. In this proof-of-concept study, we demonstrated the development of a new glucose sensor protein, AcGFP1-GBPcys-mCherry, and an optical sensor assembly, capable of generating quantifiable FRET (fluorescence resonance energy transfer) signals for glucose monitoring. Our experimental data showed that the engineered glucose sensor protein can generate measurable FRET signals in response to glucose concentrations varying from 25 to 800 μM. The sensor developed based on this protein had a shelf-life of up to 3 weeks. The sensor response was devoid of interference from compounds like galactose, fructose, lactose, mannose, and mannitol when tested at physiologically significant concentrations of these compounds. This new glucose sensor protein can potentially be used to develop implantable glucose sensors for continuous glucose monitoring.

  15. Consumption of meat is associated with higher fasting glucose and insulin concentrations regardless of glucose and insulin genetic risk scores: a meta-analysis of 50,345 Caucasians

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies suggest that meat intake is associated with diabetes-related phenotypes. However, whether the associations of meat intake and glucose and insulin homeostasis are modified by genes related to glucose and insulin is unknown. We investigated the associations of meat intake and the intera...

  16. Consumption of meat is associated with higher fasting glucose and insulin concentrations regardless of glucose and insulin genetic risk scores: a meta-analysis of 50,345 Caucasians

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: Recent studies suggest that meat intake is associated with diabetes-related phenotypes. However, whether the associations of meat intake and glucose and insulin homeostasis are modified by genes related to glucose and insulin is unknown. OBJECTIVE: We investigated the associations of mea...

  17. Does the length dependency of airway smooth muscle force contribute to airway hyperresponsiveness?

    PubMed

    Lee-Gosselin, Audrey; Pascoe, Chris D; Couture, Christian; Paré, Peter D; Bossé, Ynuk

    2013-11-01

    Airway wall remodeling and lung hyperinflation are two typical features of asthma that may alter the contractility of airway smooth muscle (ASM) by affecting its operating length. The aims of this study were as follows: 1) to describe in detail the "length dependency of ASM force" in response to different spasmogens; and 2) to predict, based on morphological data and a computational model, the consequence of this length dependency of ASM force on airway responsiveness in asthmatic subjects who have both remodeled airway walls and hyperinflated lungs. Ovine tracheal ASM strips and human bronchial rings were isolated and stimulated to contract in response to increasing concentrations of spasmogens at three different lengths. Ovine tracheal strips were more sensitive and generated greater force at longer lengths in response to acetylcholine (ACh) and K(+). Equipotent concentrations of ACh were approximately a log less for ASM stretched by 30% and approximately a log more for ASM shortened by 30%. Similar results were observed in human bronchi in response to methacholine. Morphometric and computational analyses predicted that the ASM of asthmatic subjects may be elongated by 6.6-10.4% (depending on airway generation) due to remodeling and/or hyperinflation, which could increase ACh-induced force by 1.8-117.8% (depending on ASM length and ACh concentration) and enhance the increased resistance to airflow by 0.4-4,432.8%. In conclusion, elongation of ASM imposed by airway wall remodeling and/or hyperinflation may allow ASM to operate at a longer length and to consequently generate more force and respond to lower concentration of spasmogens. This phenomenon could contribute to airway hyperresponsiveness.

  18. Protective and antidiabetic effects of extract from Nigella sativa on blood glucose concentrations against streptozotocin (STZ)-induced diabetic in rats: an experimental study with histopathological evaluation

    PubMed Central

    2013-01-01

    Background Diabetes in humans induces chronic complications such as cardiovascular damage, cataracts and retinopathy, nephropathy and polyneuropathy. The most common animal model of human diabetes is streptozotocin (STZ)-induced diabetes in the rat. The present study investigated the effects of Nigella sativa hydroalcholic extract on glucose concentrations in streptozotocin (STZ) diabetic rats. Methods In this study Twenty-five Wister-Albino rats (aged 8-9 weeks and weighing 200-250 g) were tested. Rats were divided into five experimental groups (control, untreated STZ-diabetic (60 mg/kg B.W., IP), treated STZ-diabetic with hydroalcholic extract of Nigella Sativa (NS) (5 mg/kg B.W, IP), treated STZ-diabetic with hydroalcholic extract of NS (10 mg/kg B.W., IP) and treated STZ-diabetic with hydroalcholic extract of NS (20 mg/kg B.W., IP and 32 days were evaluated to assess its effect on fasting blood glucose (FBG), and in different groups fasting blood glucose (FBG) and body weight (BW) were measured in the particular days (1, 16 and 32). At the end of the study, the animals were fasted overnight, anaesthetized with an intraperitoneal injection of sodium pentobarbital (60 mg/kg), and sacrificed for obtaining tissues samples (liver, pancreases). The number of islets and cells were counted and the islet diameters were determined by calibrated micrometer. The glycogen content in the liver was examined by Periodic Acid-Schiff (PAS) staining. Results Treatment with NS (5 mg/kg b.w.) markedly increased BW gain and the FBG level was significantly (p<0.001) reduced when compared to the control. Histopathological examination showed that the NS (5 mg/kg b.w.) partially recovered hepatic glycogen content and protected the great deal of the pancreatic islet cells. The number of islets, cells and islets diameter were found statistically significant when compared to the control (p<0.01, p<0.05). Conclusions Higher doses of NS did not exhibit any therapeutic effect. These results

  19. Cold weather exercise and airway cytokine expression.

    PubMed

    Davis, Michael S; Malayer, Jerry R; Vandeventer, Lori; Royer, Christopher M; McKenzie, Erica C; Williamson, Katherine K

    2005-06-01

    Athletes who perform repeated exercise while breathing cold air have a high prevalence of asthmalike chronic airway disease, but the mechanism linking such activity to airway inflammation is unknown. We used a novel animal model (exercising horses) to test the hypothesis that exercise-induced chronic airway disease is caused by exposure of intrapulmonary airways to unconditioned air, resulting in the upregulation of cytokine expression. Bronchoalveolar lavage fluid (BALF) was obtained from eight horses 5 h after submaximal exercise while they breathed room temperature or subfreezing air in a random crossover design. BALF total and differential nucleated cell counts were determined, and relative cytokine mRNA expression in BALF nucleated cells was quantified by real-time RT-PCR using primer and probe sequences specific for equine targets. There were no significant changes in total or differential cell concentrations between BALF recovered after warm and cold air exercise, although there was a strong trend toward increased concentrations of airway epithelial cells after cold air exercise (P = 0.0625). T(H)2 cytokines IL-4, IL-5, and IL-10 were preferentially upregulated after cold air exercise 12-, 9-, and 10-fold, respectively, compared with warm air exercise. Other cytokines (IL-2 and IL-6) were upregulated to a lesser extent (6- and 3-fold, respectively) or not at all (IL-1, IL-8, IFN-gamma, and TNF-alpha). These results suggest that cold weather exercise can lead to asthmalike airway disease through the local induction of cytokines typical of the T(H)2 phenotype.

  20. Coordinated release of nucleotides and mucin from human airway epithelial Calu-3 cells

    PubMed Central

    Kreda, Silvia M; Okada, Seiko F; van Heusden, Catharina A; O'Neal, Wanda; Gabriel, Sherif; Abdullah, Lubna; Davis, C William; Boucher, Richard C; Lazarowski, Eduardo R

    2007-01-01

    The efficiency of the mucociliary clearance (MCC) process that removes noxious materials from airway surfaces depends on the balance between mucin secretion, airway surface liquid (ASL) volume, and ciliary beating. Effective mucin dispersion into ASL requires salt and water secretion onto the mucosal surface, but how mucin secretion rate is coordinated with ion and, ultimately, water transport rates is poorly understood. Several components of MCC, including electrolyte and water transport, are regulated by nucleotides in the ASL interacting with purinergic receptors. Using polarized monolayers of airway epithelial Calu-3 cells, we investigated whether mucin secretion was accompanied by nucleotide release. Electron microscopic analyses of Calu-3 cells identified subapical granules that resembled goblet cell mucin granules. Real-time confocal microscopic analyses revealed that subapical granules, labelled with FM 1-43 or quinacrine, were competent for Ca2+-regulated exocytosis. Granules containing MUC5AC were apically secreted via Ca2+-regulated exocytosis as demonstrated by combined immunolocalization and slot blot analyses. In addition, Calu-3 cells exhibited Ca2+-regulated apical release of ATP and UDP-glucose, a substrate of glycosylation reactions within the secretory pathway. Neither mucin secretion nor ATP release from Calu-3 cells were affected by activation or inhibition of the cystic fibrosis transmembrane conductance regulator. In SPOC1 cells, an airway goblet cell model, purinergic P2Y2 receptor-stimulated increase of cytosolic Ca2+ concentration resulted in secretion of both mucins and nucleotides. Our data suggest that nucleotide release is a mechanism by which mucin-secreting goblet cells produce paracrine signals for mucin hydration within the ASL. PMID:17656429

  1. Coordinated release of nucleotides and mucin from human airway epithelial Calu-3 cells.

    PubMed

    Kreda, Silvia M; Okada, Seiko F; van Heusden, Catharina A; O'Neal, Wanda; Gabriel, Sherif; Abdullah, Lubna; Davis, C William; Boucher, Richard C; Lazarowski, Eduardo R

    2007-10-01

    The efficiency of the mucociliary clearance (MCC) process that removes noxious materials from airway surfaces depends on the balance between mucin secretion, airway surface liquid (ASL) volume, and ciliary beating. Effective mucin dispersion into ASL requires salt and water secretion onto the mucosal surface, but how mucin secretion rate is coordinated with ion and, ultimately, water transport rates is poorly understood. Several components of MCC, including electrolyte and water transport, are regulated by nucleotides in the ASL interacting with purinergic receptors. Using polarized monolayers of airway epithelial Calu-3 cells, we investigated whether mucin secretion was accompanied by nucleotide release. Electron microscopic analyses of Calu-3 cells identified subapical granules that resembled goblet cell mucin granules. Real-time confocal microscopic analyses revealed that subapical granules, labelled with FM 1-43 or quinacrine, were competent for Ca(2+)-regulated exocytosis. Granules containing MUC5AC were apically secreted via Ca(2+)-regulated exocytosis as demonstrated by combined immunolocalization and slot blot analyses. In addition, Calu-3 cells exhibited Ca(2+)-regulated apical release of ATP and UDP-glucose, a substrate of glycosylation reactions within the secretory pathway. Neither mucin secretion nor ATP release from Calu-3 cells were affected by activation or inhibition of the cystic fibrosis transmembrane conductance regulator. In SPOC1 cells, an airway goblet cell model, purinergic P2Y(2) receptor-stimulated increase of cytosolic Ca(2+) concentration resulted in secretion of both mucins and nucleotides. Our data suggest that nucleotide release is a mechanism by which mucin-secreting goblet cells produce paracrine signals for mucin hydration within the ASL.

  2. Medicinal values of fruit peels from Citrus sinensis, Punica granatum, and Musa paradisiaca with respect to alterations in tissue lipid peroxidation and serum concentration of glucose, insulin, and thyroid hormones.

    PubMed

    Parmar, Hamendra Singh; Kar, Anand

    2008-06-01

    Peel extracts from Citrus sinensis, Punica granatum, and Musa paradisiaca were investigated for their effects on tissue lipid peroxidation (LPO) and on the concentration of thyroid hormones, insulin, and glucose in male rats. In vitro inhibition of H(2)O(2)-induced LPO in red blood cells of rats by 0.25, 0.50, 1.0, and 2.0 microg/mL C. sinensis, P. granatum, and M. paradisiaca peel extracts was observed in a dose-specific manner. Maximum inhibition was observed at 0.50 microg/mL C. sinensis, 2.0 microg/mL P. granatum, and 1.0 microg/mL M. paradisiaca. In the in vivo investigation, out of four different concentrations of each peel extract, 25, 200, and 100 mg/kg C. sinensis, P. granatum, and M. paradisiaca, respectively, were found to maximally inhibit hepatic LPO. The most effective doses were further evaluated for effects on serum triiodothyronine (T(3)), thyroxine (T(4)), insulin, and glucose concentrations. C. sinensis exhibited antithyroidal, hypoglycemic, and insulin stimulatory activities, in addition to inhibition of LPO, as it significantly decreased the serum T(4) (P < .05) and glucose (P < .001) concentrations with a concomitant increase in insulin levels (P < .05). P. granatum decreased LPO in hepatic, cardiac, and renal tissues (P < .01, P < .001, and P < .05, respectively) and serum glucose concentration (P < .01). M. paradisiaca strongly inhibited the serum level of thyroid hormones (P < .01 for both T(3) and T(4)) but increased the level of glucose (P < .05). These findings reveal the hitherto unknown potential of the tested peel extracts in the regulation of thyroid function and glucose metabolism. Besides antiperoxidative activity, C. sinensis extract has antithyroidal, hypoglycemic, and insulin stimulatory properties, which suggest its potential to ameliorate both hyperthyroidism and diabetes mellitus.

  3. Mechanosensitive ATP Release Maintains Proper Mucus Hydration of Airways

    PubMed Central

    Button, Brian; Okada, Seiko F.; Frederick, Charles Brandon; Thelin, William R.; Boucher, Richard C.

    2013-01-01

    The clearance of mucus from the airways protects the lungs from inhaled noxious and infectious materials. Proper hydration of the mucus layer enables efficient mucus clearance through beating of cilia on airway epithelial cells, and reduced clearance of excessively concentrated mucus occurs in patients with chronic obstructive pulmonary disease and cystic fibrosis. Key steps in the mucus transport process are airway epithelia sensing and responding to changes in mucus hydration. We reported that extracellular adenosine triphosphate (ATP) and adenosine were important luminal auto-crine and paracrine signals that regulated the hydration of the surface of human airway epithelial cultures through their action on apical membrane purinoceptors. Mucus hydration in human airway epithelial cultures was sensed by an interaction between cilia and the overlying mucus layer: Changes in mechanical strain, proportional to mucus hydration, regulated ATP release rates, adjusting fluid secretion to optimize mucus layer hydration. This system provided a feedback mechanism by which airways maintained mucus hydration in an optimum range for cilia propulsion. Understanding how airway epithelia can sense and respond to changes in mucus properties helps us to understand how the mucus clearance system protects the airways in health and how it fails in lung diseases such as cystic fibrosis. PMID:23757023

  4. Mechanosensitive ATP release maintains proper mucus hydration of airways.

    PubMed

    Button, Brian; Okada, Seiko F; Frederick, Charles Brandon; Thelin, William R; Boucher, Richard C

    2013-06-11

    The clearance of mucus from the airways protects the lungs from inhaled noxious and infectious materials. Proper hydration of the mucus layer enables efficient mucus clearance through beating of cilia on airway epithelial cells, and reduced clearance of excessively concentrated mucus occurs in patients with chronic obstructive pulmonary disease and cystic fibrosis. Key steps in the mucus transport process are airway epithelia sensing and responding to changes in mucus hydration. We reported that extracellular adenosine triphosphate (ATP) and adenosine were important luminal autocrine and paracrine signals that regulated the hydration of the surface of human airway epithelial cultures through their action on apical membrane purinoceptors. Mucus hydration in human airway epithelial cultures was sensed by an interaction between cilia and the overlying mucus layer: Changes in mechanical strain, proportional to mucus hydration, regulated ATP release rates, adjusting fluid secretion to optimize mucus layer hydration. This system provided a feedback mechanism by which airways maintained mucus hydration in an optimum range for cilia propulsion. Understanding how airway epithelia can sense and respond to changes in mucus properties helps us to understand how the mucus clearance system protects the airways in health and how it fails in lung diseases such as cystic fibrosis.

  5. Optoelectronic Apparatus Measures Glucose Noninvasively

    NASA Technical Reports Server (NTRS)

    Ansari, Rafat R.; Rovati, Luigi L.

    2003-01-01

    An optoelectronic apparatus has been invented as a noninvasive means of measuring the concentration of glucose in the human body. The apparatus performs polarimetric and interferometric measurements of the human eye to acquire data from which the concentration of glucose in the aqueous humor can be computed. Because of the importance of the concentration of glucose in human health, there could be a large potential market for instruments based on this apparatus.

  6. The switch from xylose to glucose stalled by repression of xylose-utilizing enzymes during exposure of Scheffersomyces (Pichia) stipitis to high ethanol concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the fermentation of lignocellulosic hydrolyzates to ethanol by Scheffersomyces (Pichia) stipitis NRRL Y-7124 (CBS 5773), the switch from glucose to xylose uptake results in a diauxic lag unless process strategies to prevent this are applied. When cells were grown on glucose, the length of th...

  7. Airway epithelium stimulates smooth muscle proliferation.

    PubMed

    Malavia, Nikita K; Raub, Christopher B; Mahon, Sari B; Brenner, Matthew; Panettieri, Reynold A; George, Steven C

    2009-09-01

    Communication between the airway epithelium and stroma is evident during embryogenesis, and both epithelial shedding and increased smooth muscle proliferation are features of airway remodeling. Hence, we hypothesized that after injury the airway epithelium could modulate airway smooth muscle proliferation. Fully differentiated primary normal human bronchial epithelial (NHBE) cells at an air-liquid interface were co-cultured with serum-deprived normal primary human airway smooth muscle cells (HASM) using commercially available Transwells. In some co-cultures, the NHBE were repeatedly (x4) scrape-injured. An in vivo model of tracheal injury consisted of gently denuding the tracheal epithelium (x3) of a rabbit over 5 days and then examining the trachea by histology 3 days after the last injury. Our results show that HASM cell number increases 2.5-fold in the presence of NHBE, and 4.3-fold in the presence of injured NHBE compared with HASM alone after 8 days of in vitro co-culture. In addition, IL-6, IL-8, monocyte chemotactic protein (MCP)-1 and, more markedly, matrix metalloproteinase (MMP)-9 concentration increased in co-culture correlating with enhanced HASM growth. Inhibiting MMP-9 release significantly attenuated the NHBE-dependent HASM proliferation in co-culture. In vivo, the injured rabbit trachea demonstrated proliferation in the smooth muscle (trachealis) region and significant MMP-9 staining, which was absent in the uninjured control. The airway epithelium modulates smooth muscle cell proliferation via a mechanism that involves secretion of soluble mediators including potential smooth muscle mitogens such as IL-6, IL-8, and MCP-1, but also through a novel MMP-9-dependent mechanism.

  8. Upper airway radiographs in infants with upper airway insufficiency.

    PubMed Central

    Tonkin, S L; Davis, S L; Gunn, T R

    1994-01-01

    Upper airway measurements in nine infants considered to be at risk of upper airway insufficiency, six of whom presented after an apnoeic episode, were compared with measurements taken in two age groups of healthy infants. Paired, inspiratory and expiratory, lateral upper airway radiographs were obtained while the infants were awake and breathing quietly. The radiographs of all nine infants demonstrated narrowing in the oropharyngeal portion of the airway during inspiration and in six infants there was ballooning of the upper airway during expiration. Seven of the nine infants subsequently experienced recurrent apnoeic episodes which required vigorous stimulation to restore breathing. Experience suggests that respiratory phase timed radiographs are a useful adjunct to the evaluation of infants who are suspected of having upper airway dysfunction. They provide information regarding both the dimensions and compliance of the upper airway as well as the site of any restriction. Images PMID:8048825

  9. Digestive efficiencies of Cape white-eyes (Zosterops virens), red-winged starlings (Onychognathus morio) and speckled mousebirds (Colius striatus) fed varying concentrations of equicaloric glucose or sucrose artificial fruit diets.

    PubMed

    Zungu, Manqoba M; Downs, Colleen T

    2016-09-01

    Digestive physiology is important for understanding the feeding behaviour of organisms. Specifically, studies on the digestive physiology of frugivorous and nectarivorous birds are important for elucidating their preference patterns in the wild and the selective pressures they exert on fruit pulp and nectar. In this study, digesta transit times and digestive efficiencies of three species of birds, the Cape white-eyes (Zosterops virens), red-winged starlings (Onychognathus morio) and speckled mousebirds (Colius striatus) were investigated on equicaloric glucose or sucrose artificial fruit diets. Three concentrations, approximating the natural range of sugar concentrations in sugary, bird-dispersed fruits were used: low (6.6%), medium (12.4%) and high (22%). Digesta transit times of birds increased with an increase in concentration for all diets but were generally higher on glucose diets. Intake rates, on the other hand, decreased with an increase in sugar concentration. All species of birds failed to maintain a constant assimilated energy intake on glucose diets but mousebirds and white-eyes maintained it on sucrose diets. Apparent assimilation efficiencies of glucose diets for all species were comparable and typical of those found in other frugivorous birds. However, assimilation efficiencies for sucrose diets differed widely with red-winged starlings displaying very low assimilation efficiencies and as a consequence; they lost significant body mass on all sucrose diets. These results demonstrate the importance of digestive physiology in explaining fruit selection patterns in frugivorous birds and how a seemingly trivial physiological trait can have dire ecological consequences.

  10. Activities of enzymes of fat and ketone-body metabolism and effects of starvation on blood concentrations of glucose and fat fuels in teleost and elasmobranch fish

    PubMed Central

    Zammit, Victor A.; Newsholme, Eric A.

    1979-01-01

    1. Activities of 3-oxo acid CoA-transferase and carnitine palmitoyltransferase together with tri- and di-acylglycerol lipase were present in red and heart muscles of the teleost fish. However, d-3-hydroxybutyrate dehydrogenase activity was not detectable. These results suggest that the heart and red muscles of the teleosts should be able to utilize the fat fuels triacylglycerol, fatty acids or acetoacetate, but not hydroxybutyrate. The muscles from the elasmobranchs differed in that d-3-hydroxybutyrate dehydrogenase and 3-oxo acid CoA-transferase activities were present, but carnitine palmitoyltransferase activity was not detectable. This suggests that ketone bodies are the most important fat fuels in elasmobranchs. 2. The concentrations of acetoacetate, 3-hydroxybutyrate, glycerol, non-esterified fatty acids and triacylglycerols were measured in blood or plasma of several species of fish (teleosts and elasmobranchs) in the fed state. Teleosts have a 10-fold higher concentration of plasma non-esterified fatty acids, but a lower blood concentration of ketone bodies; both acetoacetate and 3-hydroxybutyrate are present in blood of elasmobranchs, whereas 3-hydroxybutyrate is absent from that of the teleosts. 3. The effects of starvation (up to 150 days) on the concentrations of blood metabolites were studied in a teleost (bass) and an elasmobranch (dogfish). In the bass there was a 60% decrease in blood glucose after 100 and 150 days starvation. In dogfish there was a large increase in the concentration of ketone bodies, whereas in bass the concentration of acetoacetate (the only ketone body present) remained low (<0.04mm) throughout the period of starvation. The concentration of plasma non-esterified fatty acids increased in bass, but decreased in dogfish. These changes are consistent with the predictions based on the enzyme-activity data. 4. Starvation did not change the activities of ketone-body-utilizing enzymes or that of phosphoenolpyruvate carboxykinase in heart

  11. Acute pulmonary edema and airway hemorrhage in a goat during sevoflurane anesthesia.

    PubMed

    Adami, C; Levionnois, O; Spadavecchia, C

    2011-02-01

    A goat was scheduled for experimental surgery under general anesthesia. The first attempt of performing endotracheal intubation failed and provoked laryngeal spasm. After repeated succesful intubation of inhalation anesthesia was delivered in high concentrations of sevoflurane. Suddenly hypertension and tachycardia were observed, followed by foamy airway secretion and then severe airway hemorrhage. The authors hypothesize that laryngeal spasm provoked respiratory distress and pulmonary edema. The delivered high concentrations of sevoflurane probably enhanced a hyperadrenergic response, predisposing to the development of airway hemorrhage.

  12. Hyperglycaemia and Pseudomonas aeruginosa acidify cystic fibrosis airway surface liquid by elevating epithelial monocarboxylate transporter 2 dependent lactate-H+ secretion

    PubMed Central

    Garnett, James Peter; Kalsi, Kameljit K.; Sobotta, Mirko; Bearham, Jade; Carr, Georgina; Powell, Jason; Brodlie, Malcolm; Ward, Christopher; Tarran, Robert; Baines, Deborah L.

    2016-01-01

    The cystic fibrosis (CF) airway surface liquid (ASL) provides a nutrient rich environment for bacterial growth including elevated glucose, which together with defective bacterial killing due to aberrant HCO3− transport and acidic ASL, make the CF airways susceptible to colonisation by respiratory pathogens such as Pseudomonas aeruginosa. Approximately half of adults with CF have CF related diabetes (CFRD) and this is associated with increased respiratory decline. CF ASL contains elevated lactate concentrations and hyperglycaemia can also increase ASL lactate. We show that primary human bronchial epithelial (HBE) cells secrete lactate into ASL, which is elevated in hyperglycaemia. This leads to ASL acidification in CFHBE, which could only be mimicked in non-CF HBE following HCO3− removal. Hyperglycaemia-induced changes in ASL lactate and pH were exacerbated by the presence of P. aeruginosa and were attenuated by inhibition of monocarboxylate lactate-H+ co-transporters (MCTs) with AR-C155858. We conclude that hyperglycaemia and P. aeruginosa induce a metabolic shift which increases lactate generation and efflux into ASL via epithelial MCT2 transporters. Normal airways compensate for MCT-driven H+ secretion by secreting HCO3−, a process which is dysfunctional in CF airway epithelium leading to ASL acidification and that these processes may contribute to worsening respiratory disease in CFRD. PMID:27897253

  13. Hyperglycaemia and Pseudomonas aeruginosa acidify cystic fibrosis airway surface liquid by elevating epithelial monocarboxylate transporter 2 dependent lactate-H(+) secretion.

    PubMed

    Garnett, James Peter; Kalsi, Kameljit K; Sobotta, Mirko; Bearham, Jade; Carr, Georgina; Powell, Jason; Brodlie, Malcolm; Ward, Christopher; Tarran, Robert; Baines, Deborah L

    2016-11-29

    The cystic fibrosis (CF) airway surface liquid (ASL) provides a nutrient rich environment for bacterial growth including elevated glucose, which together with defective bacterial killing due to aberrant HCO3(-) transport and acidic ASL, make the CF airways susceptible to colonisation by respiratory pathogens such as Pseudomonas aeruginosa. Approximately half of adults with CF have CF related diabetes (CFRD) and this is associated with increased respiratory decline. CF ASL contains elevated lactate concentrations and hyperglycaemia can also increase ASL lactate. We show that primary human bronchial epithelial (HBE) cells secrete lactate into ASL, which is elevated in hyperglycaemia. This leads to ASL acidification in CFHBE, which could only be mimicked in non-CF HBE following HCO3(-) removal. Hyperglycaemia-induced changes in ASL lactate and pH were exacerbated by the presence of P. aeruginosa and were attenuated by inhibition of monocarboxylate lactate-H(+) co-transporters (MCTs) with AR-C155858. We conclude that hyperglycaemia and P. aeruginosa induce a metabolic shift which increases lactate generation and efflux into ASL via epithelial MCT2 transporters. Normal airways compensate for MCT-driven H(+) secretion by secreting HCO3(-), a process which is dysfunctional in CF airway epithelium leading to ASL acidification and that these processes may contribute to worsening respiratory disease in CFRD.

  14. Glucose Variability

    PubMed Central

    Le Floch, Jean-Pierre; Kessler, Laurence

    2016-01-01

    Background: Glucose variability has been suspected to be a major factor of diabetic complications. Several indices have been proposed for measuring glucose variability, but their interest remains discussed. Our aim was to compare different indices. Methods: Glucose variability was studied in 150 insulin-treated diabetic patients (46% men, 42% type 1 diabetes, age 52 ± 11 years) using a continuous glucose monitoring system (668 ± 564 glucose values; mean glucose value 173 ± 38 mg/dL). Results from the mean, the median, different indices (SD, MAGE, MAG, glucose fluctuation index (GFI), and percentages of low [<60 mg/dL] and high [>180 mg/dL] glucose values), and ratios (CV = SD/m, MAGE/m, MAG/m, and GCF = GFI/m) were compared using Pearson linear correlations and a multivariate principal component analysis (PCA). Results: CV, MAGE/m (ns), GCF and GFI (P < .05), MAG and MAG/m (P < .01) were not strongly correlated with the mean. The percentage of high glucose values was mainly correlated with indices. The percentage of low glucose values was mainly correlated with ratios. PCA showed 3 main axes; the first was associated with descriptive data (mean, SD, CV, MAGE, MAGE/m, and percentage of high glucose values); the second with ratios MAG/m and GCF and with the percentage of low glucose values; and the third with MAG, GFI, and the percentage of high glucose values. Conclusions: Indices and ratios provide complementary pieces of information associated with high and low glucose values, respectively. The pairs MAG+MAG/m and GFI+GCF appear to be the most reliable markers of glucose variability in diabetic patients. PMID:26880391

  15. Supraglottic airway devices in children

    PubMed Central

    Ramesh, S; Jayanthi, R

    2011-01-01

    Modern anaesthesia practice in children was made possible by the invention of the endotracheal tube (ET), which made lengthy and complex surgical procedures feasible without the disastrous complications of airway obstruction, aspiration of gastric contents or asphyxia. For decades, endotracheal intubation or bag-and-mask ventilation were the mainstays of airway management. In 1983, this changed with the invention of the laryngeal mask airway (LMA), the first supraglottic airway device that blended features of the facemask with those of the ET, providing ease of placement and hands-free maintenance along with a relatively secure airway. The invention and development of the LMA by Dr. Archie Brain has had a significant impact on the practice of anaesthesia, management of the difficult airway and cardiopulmonary resuscitation in children and neonates. This review article will be a brief about the clinical applications of supraglottic airways in children. PMID:22174464

  16. Electrolyte transport properties in distal small airways from cystic fibrosis pigs with implications for host defense

    PubMed Central

    Tang, Xiao Xiao; Vargas Buonfiglio, Luis G.; Comellas, Alejandro P.; Thornell, Ian M.; Ramachandran, Shyam; Karp, Philip H.; Taft, Peter J.; Sheets, Kelsey; Abou Alaiwa, Mahmoud H.; Welsh, Michael J.; Stoltz, David A.; Zabner, Joseph

    2016-01-01

    While pathological and clinical data suggest that small airways are involved in early cystic fibrosis (CF) lung disease development, little is known about how the lack of cystic fibrosis transmembrane conductance regulator (CFTR) function contributes to disease pathogenesis in these small airways. Large and small airway epithelia are exposed to different airflow velocities, temperatures, humidity, and CO2 concentrations. The cellular composition of these two regions is different, and small airways lack submucosal glands. To better understand the ion transport properties and impacts of lack of CFTR function on host defense function in small airways, we adapted a novel protocol to isolate small airway epithelial cells from CF and non-CF pigs and established an organotypic culture model. Compared with non-CF large airways, non-CF small airway epithelia cultures had higher Cl− and bicarbonate (HCO3−) short-circuit currents and higher airway surface liquid (ASL) pH under 5% CO2 conditions. CF small airway epithelia were characterized by minimal Cl− and HCO3− transport and decreased ASL pH, and had impaired bacterial killing compared with non-CF small airways. In addition, CF small airway epithelia had a higher ASL viscosity than non-CF small airways. Thus, the activity of CFTR is higher in the small airways, where it plays a role in alkalinization of ASL, enhancement of antimicrobial activity, and lowering of mucus viscosity. These data provide insight to explain why the small airways are a susceptible site for the bacterial colonization. PMID:26801568

  17. Reproducibility of airway wall thickness measurements

    NASA Astrophysics Data System (ADS)

    Schmidt, Michael; Kuhnigk, Jan-Martin; Krass, Stefan; Owsijewitsch, Michael; de Hoop, Bartjan; Peitgen, Heinz-Otto

    2010-03-01

    Airway remodeling and accompanying changes in wall thickness are known to be a major symptom of chronic obstructive pulmonary disease (COPD), associated with reduced lung function in diseased individuals. Further investigation of this disease as well as monitoring of disease progression and treatment effect demand for accurate and reproducible assessment of airway wall thickness in CT datasets. With wall thicknesses in the sub-millimeter range, this task remains challenging even with today's high resolution CT datasets. To provide accurate measurements, taking partial volume effects into account is mandatory. The Full-Width-at-Half-Maximum (FWHM) method has been shown to be inappropriate for small airways1,2 and several improved algorithms for objective quantification of airway wall thickness have been proposed.1-8 In this paper, we describe an algorithm based on a closed form solution proposed by Weinheimer et al.7 We locally estimate the lung density parameter required for the closed form solution to account for possible variations of parenchyma density between different lung regions, inspiration states and contrast agent concentrations. The general accuracy of the algorithm is evaluated using basic tubular software and hardware phantoms. Furthermore, we present results on the reproducibility of the algorithm with respect to clinical CT scans, varying reconstruction kernels, and repeated acquisitions, which is crucial for longitudinal observations.

  18. The Effect of Glucose Concentration and Sodium Phenylbutyrate Treatment on Mitochondrial Bioenergetics and ER Stress in 3T3-L1 Adipocytes

    PubMed Central

    Tanis, Ross M.; Piroli, Gerardo G.; Day, Stani D.; Frizzell, Norma

    2016-01-01

    While the 3T3-L1 adipocyte model is routinely used for the study of obesity and diabetes, the mitochondrial respiratory profile in normal versus high glucose has not been examined in detail. We matured adipocytes in normal (5 mM) or high (30 mM) glucose and insulin and examined the mitochondrial bioenergetics. We also assessed the requirement for the Unfolded Protein Response (UPR) and ER stress under these conditions. Basal respiration was ∼1.7-fold greater in adipocytes that had matured in 30 mM glucose; however, their ability to increase oxygen consumption in response to stress was impaired. Adipogenesis proceeded in both normal and high glucose with concomitant activation of the UPR, but only high glucose was associated with increased levels of ER stress and mitochondrial stress as observed by parallel increases in CHOP and protein succination. Treatment of adipocytes with sodium phenylbutyrate relieved mitochondrial stress through a reduction in mitochondrial respiration. Our data suggests that mitochondrial stress, protein succination and ER stress are uniquely linked in adipocytes matured in high glucose. PMID:25448036

  19. Regulation of Blood Glucose Concentration in Type 1 Diabetics Using Single Order Sliding Mode Control Combined with Fuzzy On-line Tunable Gain, a Simulation Study

    PubMed Central

    Dinani, Soudabeh Taghian; Zekri, Maryam; Kamali, Marzieh

    2015-01-01

    Diabetes is considered as a global affecting disease with an increasing contribution to both mortality rate and cost damage in the society. Therefore, tight control of blood glucose levels has gained significant attention over the decades. This paper proposes a method for blood glucose level regulation in type 1 diabetics. The control strategy is based on combining the fuzzy logic theory and single order sliding mode control (SOSMC) to improve the properties of sliding mode control method and to alleviate its drawbacks. The aim of the proposed controller that is called SOSMC combined with fuzzy on-line tunable gain is to tune the gain of the controller adaptively. This merit causes a less amount of control effort, which is the rate of insulin delivered to the patient body. As a result, this method can decline the risk of hypoglycemia, a lethal phenomenon in regulating blood glucose level in diabetics caused by a low blood glucose level. Moreover, it attenuates the chattering observed in SOSMC significantly. It is worth noting that in this approach, a mathematical model called minimal model is applied instead of the intravenously infused insulin–blood glucose dynamics. The simulation results demonstrate a good performance of the proposed controller in meal disturbance rejection and robustness against parameter changes. In addition, this method is compared to fuzzy high-order sliding mode control (FHOSMC) and the superiority of the new method compared to FHOSMC is shown in the results. PMID:26284169

  20. Airway drug pharmacokinetics via analysis of exhaled breath condensate.

    PubMed

    Esther, Charles R; Boucher, Richard C; Johnson, M Ross; Ansede, John H; Donn, Karl H; O'Riordan, Thomas G; Ghio, Andrew J; Hirsh, Andrew J

    2014-02-01

    Although the airway surface is the anatomic target for many lung disease therapies, measuring drug concentrations and activities on these surfaces poses considerable challenges. We tested whether mass spectrometric analysis of exhaled breath condensate (EBC) could be utilized to non-invasively measure airway drug pharmacokinetics and predicted pharmacological activities. Mass spectrometric methods were developed to detect a novel epithelial sodium channel blocker (GS-9411/P-680), two metabolites, a chemically related internal standard, plus naturally occurring solutes including urea as a dilution marker. These methods were then applied to EBC and serum collected from four (Floridian) sheep before, during and after inhalation of nebulized GS-9411/P-680. Electrolyte content of EBC and serum was also assessed as a potential pharmacodynamic marker of drug activity. Airway surface concentrations of drug, metabolites, and electrolytes were calculated from EBC measures using EBC:serum urea based dilution factors. GS-9411/P-680 and its metabolites were quantifiable in the sheep EBC, with peak airway concentrations between 1.9 and 3.4 μM measured 1 h after inhalation. In serum, only Metabolite #1 was quantifiable, with peak concentrations ∼60-fold lower than those in the airway (45 nM at 1 h). EBC electrolyte concentrations suggested a pharmacological effect; but this effect was not statistical significant. Analysis of EBC collected during an inhalation drug study provided a method for quantification of airway drug and metabolites via mass spectrometry. Application of this methodology could provide an important tool in development and testing of drugs for airways diseases.

  1. 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

  2. Consumption of fructose- but not glucose-sweetened beverages for 10 weeks increases circulating concentrations of uric acid, retinol binding protein-4, and gamma-glutamyl transferase activity in overweight/obese humans

    PubMed Central

    2012-01-01

    Background Prospective studies in humans examining the effects of fructose consumption on biological markers associated with the development of metabolic syndrome are lacking. Therefore we investigated the relative effects of 10 wks of fructose or glucose consumption on plasma uric acid and RBP-4 concentrations, as well as liver enzyme (AST, ALT, and GGT) activities in men and women. Methods As part of a parallel arm study, older (age 40–72), overweight and obese male and female subjects (BMI 25–35 kg/m2) consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 wks. Fasting and 24-h blood collections were performed at baseline and following 10 wks of intervention and plasma concentrations of uric acid, RBP-4 and liver enzyme activities were measured. Results Consumption of fructose, but not glucose, led to significant increases of 24-h uric acid profiles (P < 0.0001) and RBP-4 concentrations (P = 0.012), as well as plasma GGT activity (P = 0.04). Fasting plasma uric acid concentrations increased in both groups; however, the response was significantly greater in subjects consuming fructose (P = 0.002 for effect of sugar). Within the fructose group male subjects exhibited larger increases of RBP-4 levels than women (P = 0.024). Conclusions These findings suggest that consumption of fructose at 25% of energy requirements for 10 wks, compared with isocaloric consumption of glucose, may contribute to the development of components of the metabolic syndrome by increasing circulating uric acid, GGT activity, suggesting alteration of hepatic function, and the production of RBP-4. PMID:22828276

  3. The study of the influence of temperature and initial glucose concentration on the fermentation process in the presence of Saccharomyces cerevisiae yeast strain immobilized on starch gels by reversed-flow gas chromatography.

    PubMed

    Lainioti, G Ch; Kapolos, J; Koliadima, A; Karaiskakis, G

    2012-01-01

    The technique of reversed-flow gas chromatography (RFGC) was employed for the determination of the alcoholic fermentation phases and of kinetic parameters for free and immobilized cell systems, at different initial glucose concentrations and temperature values. In addition to this, due to its considerable advantages over other techniques, RFGC was used for the characterization of a new biocatalyst, yeast cells immobilized on starch gel, and especially wheat starch gel. Immobilization of wine yeast Saccharomyces cerevisiae AXAZ-1 was accomplished on wheat and corn starch gels in order to prepare new biocatalysts with great interest for the fermentation industry. The RFGC led with great accuracy, resulting from a literature review, to the determination of reaction rate constants and activation energies at each phase of the fermentation processes. A maximum value of rate constants was observed at initial glucose concentration of 205 g/L, where a higher number of yeast cells was observed. The increase of glucose concentrations had a negative influence on the growth of AXAZ-1 cells and rate constants were decreased. The decrease of fermentation temperature caused a substantial reduction in the viability of immobilized cells as well as in rate constant values. Activation energies of corn starch gel presented lower values than those of wheat starch gel. However, the two supports showed higher catalytic efficiency than free cell systems, proving that starch gels may act as a promoter of the catalytic activity of the yeast cells involved in the fermentation process.

  4. Vascular Glucose Sensor Symposium

    PubMed Central

    Joseph, Jeffrey I; Torjman, Marc C.; Strasma, Paul J.

    2015-01-01

    Hyperglycemia, hypoglycemia, and glycemic variability have been associated with increased morbidity, mortality, length of stay, and cost in a variety of critical care and non–critical care patient populations in the hospital. The results from prospective randomized clinical trials designed to determine the risks and benefits of intensive insulin therapy and tight glycemic control have been confusing; and at times conflicting. The limitations of point-of-care blood glucose (BG) monitoring in the hospital highlight the great clinical need for an automated real-time continuous glucose monitoring system (CGMS) that can accurately measure the concentration of glucose every few minutes. Automation and standardization of the glucose measurement process have the potential to significantly improve BG control, clinical outcome, safety and cost. PMID:26078254

  5. Effects of rumen fill on short-term ingestive behavior and circulating concentrations of ghrelin, insulin, and glucose of dairy cows foraging vegetative micro-swards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of ruminal fill (RF) on foraging behaviour, intake rate and the levels of circulating ghrelin, insulin and glucose was measured with four rumen-cannulated lactating dairy cows foraging micro-swards of vegetative orchardgrass. The treatments compared were removal of 1.00 (RF0), 0.66 (RF33)...

  6. Airway inflammation in aluminium potroom asthma

    PubMed Central

    Sjaheim, T; Halstensen, T; Lund, M; Bjortuft, O; Drablos, P; Malterud, D; Kongerud, J

    2004-01-01

    Aims: To examine whether asthma induced by exposure to aluminium potroom emissions (potroom asthma) is associated with inflammatory changes in the airways. Methods: Bronchial biopsy specimens from 20 asthmatic workers (8 non-smokers and 12 smokers), 15 healthy workers (8 non-smokers and 7 smokers), and 10 non-exposed controls (all non-smokers) were analysed. Immunohistofluorescent staining was performed to identify mucosal total leucocytes (CD45+ leucocytes), neutrophils, and mast cells. Results: Median RBM thickness was significantly increased in both asthmatic workers (8.2 µm) and healthy workers (7.4 µm) compared to non-exposed controls (6.7 µm). Non-smoking asthmatic workers had significantly increased median density of lamina propria CD45+ leucocytes (1519 cells/mm2v 660 and 887 cells/mm2) and eosinophils (27 cells/mm2v 10 and 3 cells/mm2) and significantly increased concentrations of exhaled NO (18.1 ppb v 6.5 and 5.1 ppb) compared to non-smoking healthy workers and non-exposed controls. Leucocyte counts and exhaled NO concentrations varied with smoking habits and fewer leucocytes were observed in asthmatic smokers than in non-smokers Asthmatic smokers had significantly increased numbers of eosinophils in lamina propria compared to non-exposed controls (10 v 3 cells/mm2). Both eosinophilic and non-eosinophilic phenotypes of asthma were recognised in the potroom workers and signs of airway inflammation were also observed in healthy workers. Conclusions: Airway inflammation is a central feature of potroom asthma and exposure to potroom emissions induces pathological alterations similar to those described in other types of asthma. Cigarette smoking seems to affect the underlying mechanisms involved in asthma, as the cellular composition of airway mucosa appears different in asthmatic smokers and non-smokers. PMID:15317920

  7. The metabolic syndrome of fructose-fed rats: effects of long-chain polyunsaturated ω3 and ω6 fatty acids. II. Time course of changes in food intake, body weight, plasma glucose and insulin concentrations and insulin resistance.

    PubMed

    Mellouk, Zoheir; Hachimi Idrissi, Tarek; Louchami, Karim; Hupkens, Emeline; Sener, Abdullah; Yahia, Dalila Ait; Malaisse, Willy J

    2012-01-01

    The time course for changes in food intake, body weight, plasma glucose and insulin concentrations and HOMA index was monitored over a period of 8 weeks in rats exposed from the 8th week after birth to diets containing either starch or fructose and sunflower oil. In two further groups of rats exposed to the fructose-rich diet part of the sunflower oil was substituted by either salmon oil rich in long-chain polyunsaturated ω3 fatty acids or safflower oil rich in long-chain polyunsaturated ω6 fatty acids. Despite lower food intake, the gain in body weight was higher in fructose-fed rats than in starch-fed rats. The supplementation of the fructose-rich diet by either ω3 or ω6 fatty acids lowered both food intake and body weight gain. The measurements of plasma glucose and insulin concentrations, HOMA index and insulinogenic index performed after overnight starvation were in fair agreement with those recorded at the occasion of an intraperitoneal glucose tolerance test, with higher values for plasma glucose concentration and HOMA index in the fructose-fed rats exposed to the sunflower oil (with or without enrichment with ω6 fatty acids) than in the starch-fed rats exposed to the sunflower oil or fructose-fed rats exposed to a diet enriched with ω3 fatty acids. Such was also the case for the measurements of glycated albumin at sacrifice. Moreover, the insulinogenic index was lower in the fructose-fed rats with or without dietary enrichment in ω6 fatty acids than in the fructose-fed rats with dietary enrichment in ω3 fatty acids. The elucidation of the biochemical determinants of the later difference requires further investigations in isolated pancreatic islets.

  8. Operative endoscopy of the airway

    PubMed Central

    Walters, Dustin M.

    2016-01-01

    Airway endoscopy has long been an important and useful tool in the management of thoracic diseases. As thoracic specialists have gained experience with both flexible and rigid bronchoscopic techniques, the technology has continued to evolve so that bronchoscopy is currently the foundation for diagnosis and treatment of many thoracic ailments. Airway endoscopy plays a significant role in the biopsy of tumors within the airways, mediastinum, and lung parenchyma. Endoscopic methods have been developed to treat benign and malignant airway stenoses and tracheomalacia. And more recently, techniques have been conceived to treat end-stage emphysema and prolonged air leaks in select patients. This review describes the abundant uses of airway endoscopy, as well as technical considerations and limitations of the current technologies. PMID:26981263

  9. Global airway disease beyond allergy.

    PubMed

    Hellings, Peter W; Prokopakis, Emmanuel P

    2010-03-01

    Besides the anatomic continuity of the upper and lower airways, inflammation in one part of the airway influences the homeostasis of the other. The mechanisms underlying this interaction have been studied primarily in allergic disease, showing systemic immune activation, induction of inflammation at a distance, and a negative impact of nasal inflammation on bronchial homeostasis. In addition to allergy, other inflammatory conditions of the upper airways are associated with lower airway disease. Rhinosinusitis is frequently associated with asthma and chronic obstructive pulmonary disease. The impairment of purification, humidification, and warming up of the inspired air by the nose in rhinosinusitis may be responsible in part for bronchial pathology. The resolution of sinonasal inflammation via medical and/or surgical treatment is responsible for the beneficial effect of the treatment on bronchial disease. This article provides a comprehensive overview of the current knowledge of upper and lower airway communication beyond allergic disease.

  10. Recurrent airway obstruction: a review.

    PubMed

    Pirie, R S

    2014-05-01

    Recurrent airway obstruction is a widely recognised airway disorder, characterised by hypersensitivity-mediated neutrophilic airway inflammation and lower airway obstruction in a subpopulation of horses when exposed to suboptimal environments high in airborne organic dust. Over the past decade, numerous studies have further advanced our understanding of different aspects of the disease. These include clarification of the important inhaled airborne agents responsible for disease induction, improving our understanding of the underlying genetic basis of disease susceptibility and unveiling the fundamental immunological mechanisms leading to establishment of the classic disease phenotype. This review, as well as giving a clinical overview of recurrent airway obstruction, summarises much of the work in these areas that have culminated in a more thorough understanding of this debilitating disease.

  11. The airway microbiome and disease.

    PubMed

    Marsland, Benjamin J; Yadava, Koshika; Nicod, Laurent P

    2013-08-01

    Although traditionally thought to be sterile, accumulating evidence now supports the concept that our airways harbor a microbiome. Thus far, studies have focused upon characterizing the bacterial constituents of the airway microbiome in both healthy and diseased lungs, but what perhaps provides the greatest impetus for the exploration of the airway microbiome is that different bacterial phyla appear to dominate diseased as compared with healthy lungs. As yet, there is very limited evidence supporting a functional role for the airway microbiome, but continued research in this direction is likely to provide such evidence, particularly considering the progress that has been made in understanding host-microbe mutualism in the intestinal tract. In this review, we highlight the major advances that have been made discovering and describing the airway microbiome, discuss the experimental evidence that supports a functional role for the microbiome in health and disease, and propose how this emerging field is going to impact clinical practice.

  12. Wogonin Induces Eosinophil Apoptosis and Attenuates Allergic Airway Inflammation

    PubMed Central

    Dorward, David A.; Sharma, Sidharth; Rennie, Jillian; Felton, Jennifer M.; Alessandri, Ana L.; Duffin, Rodger; Schwarze, Jurgen; Haslett, Christopher; Rossi, Adriano G.

    2015-01-01

    Rationale: Eosinophils are key effector cells in allergic diseases, including allergic rhinitis, eczema, and asthma. Their tissue presence is regulated by both recruitment and increased longevity at inflamed sites. Objectives: To investigate the ability of the flavone wogonin to induce eosinophil apoptosis in vitro and attenuate eosinophil-dominant allergic inflammation in vivo in mice. Methods: Human and mouse eosinophil apoptosis in response to wogonin was investigated by cellular morphology, flow cytometry, mitochondrial membrane permeability, and pharmacological caspase inhibition. Allergic lung inflammation was modeled in mice sensitized and challenged with ovalbumin. Bronchoalveolar lavage (BAL) and lung tissue were examined for inflammation, mucus production, and inflammatory mediator production. Airway hyperresponsiveness to aerosolized methacholine was measured. Measurements and Main Results: Wogonin induced time- and concentration-dependent human and mouse eosinophil apoptosis in vitro. Wogonin-induced eosinophil apoptosis occurred with activation of caspase-3 and was inhibited by pharmacological caspase inhibition. Wogonin administration attenuated allergic airway inflammation in vivo with reductions in BAL and interstitial eosinophil numbers, increased eosinophil apoptosis, reduced airway mucus production, and attenuated airway hyperresponsiveness. This wogonin-induced reduction in allergic airway inflammation was prevented by concurrent caspase inhibition in vivo. Conclusions: Wogonin induces eosinophil apoptosis and attenuates allergic airway inflammation, suggesting that it has therapeutic potential for the treatment of allergic inflammation in humans. PMID:25629436

  13. Validation of the conceptual anatomical model of the lung airway.

    PubMed

    Fleming, John S; Sauret, Veronique; Conway, Joy H; Martonen, Ted B

    2004-01-01

    The conceptual anatomical model of the lung airway considers each lung volume divided into ten concentric shells. It specifies the volume of each airway generation in each shell, using Weibel morphometry. This study updates and validates the model and evaluates the errors obtained when using it to estimate inhaled aerosol deposition per generation from spatial imaging data. A comparison of different airway models describing the volume per generation, including data from CT images of a lung cast and a human subject, was performed. A revised version of the conceptual model was created, using the average volume per generation from these data. The new model was applied to derive the aerosol deposition per generation from 24 single photon emission computed tomography (SPECT) studies. Analysis errors were assessed by applying the same calculations but using airway models based on the minimum and maximum volumes per generation. The mean shell position of each generation in the average model was not significantly different from either CT model. However there were differences between the volumes per generation of the different models. The root mean square differences between bronchial airways deposition fraction (generations 2-8) obtained from the maximum and minimum models compared to the new average model was 0.66 percentage points (14%). For the conducting airways deposition fraction (generations 2-15) this was 1.66 percentage points (12%). The conceptual model is consistent with CT measurements of airway geometry. The errors resulting from using a generic airway model to interpret 3D radionuclide image data have been defined.

  14. An acoustic glucose sensor.

    PubMed

    Hu, Ruifen; Stevenson, Adrian C; Lowe, Christopher R

    2012-05-15

    In vivo glucose monitoring is required for tighter glycaemic control. This report describes a new approach to construct a miniature implantable device based on a magnetic acoustic resonance sensor (MARS). A ≈ 600-800 nm thick glucose-responsive poly(acrylamide-co-3-acrylamidophenylboronic acid) (poly(acrylamide-co-3-APB)) film was polymerised on the quartz disc (12 mm in diameter and 0.25 mm thick) of the MARS. The swelling/shrinking of the polymer film induced by the glucose binding to the phenylboronate caused changes in the resonance amplitude of the quartz disc in the MARS. A linear relationship between the response of the MARS and the glucose concentration in the range ≈ 0-15 mM was observed, with the optimum response of the MARS sensor being obtained when the polymer films contained ≈ 20 mol% 3-APB. The MARS glucose sensor also functioned under flow conditions (9 μl/min) with a response almost identical to the sensor under static or non-flow conditions. The results suggest that the MARS could offer a promising strategy for developing a small subcutaneously implanted continuous glucose monitor.

  15. Mulberry-extract improves glucose tolerance and decreases insulin concentrations in normoglycaemic adults: Results of a randomised double-blind placebo-controlled study

    PubMed Central

    2017-01-01

    Background High sugar and refined carbohydrate intake is associated with weight gain, increased incidence of diabetes and is linked with increased cardiovascular mortality. Reducing the health impact of poor quality carbohydrate intake is a public health priority. Reducose, a proprietary mulberry leaf extract (ME), may reduce blood glucose responses following dietary carbohydrate intake by reducing absorption of glucose from the gut. Methods A double-blind, randomised, repeat measure, phase 2 crossover design was used to study the glycaemic and insulinaemic response to one reference product and three test products at the Functional Food Centre, Oxford Brooks University, UK. Participants; 37 adults aged 19–59 years with a BMI ≥ 20kg/m2 and ≤ 30kg/m2. The objective was to determine the effect of three doses of mulberry-extract (Reducose) versus placebo on blood glucose and insulin responses when co-administered with 50g maltodextrin in normoglycaemic healthy adults. We also report the gastrointestinal tolerability of the mulberry extract. Results Thirty-seven participants completed the study: The difference in the positive Incremental Area Under the Curve (pIAUC) (glucose (mmol / L x h)) for half, normal and double dose ME compared with placebo was -6.1% (-18.2%, 5.9%; p = 0.316), -14.0% (-26.0%, -2.0%; p = 0.022) and -22.0% (-33.9%, -10.0%; p<0.001) respectively. The difference in the pIAUC (insulin (mIU / L x h)) for half, normal and double dose ME compared with placebo was -9.7% (-25.8%, 6.3%; p = 0.234), -23.8% (-39.9%, -7.8%; p = 0.004) and -24.7% (-40.8%, -8.6%; p = 0.003) respectively. There were no statistically significant differences between any of the 4 groups in the odds of experiencing one or more gastrointestinal symptoms (nausea, abdominal cramping, distension or flatulence). Conclusions Mulberry leaf extract significantly reduces total blood glucose rise after ingestion of maltodextrin over 120 minutes. The pattern of effect demonstrates a

  16. Beneficial effects of severe sleep apnea therapy on nocturnal glucose control in persons with type 2 diabetes mellitus.

    PubMed

    Pallayova, Maria; Donic, Viliam; Tomori, Zoltan

    2008-07-01

    Given the consequences of sleep apnea and coexisting diabetes, satisfactory treatment of both diseases is required. Our results of continuous glucose monitoring in severe sleep apnea diabetic patients before and during continuous positive airway pressure/CPAP therapy showed significant reduction of nocturnal glucose variability and improved overnight glucose control on CPAP.

  17. Glucose metabolism and hyperglycemia.

    PubMed

    Giugliano, Dario; Ceriello, Antonio; Esposito, Katherine

    2008-01-01

    Islet dysfunction and peripheral insulin resistance are both present in type 2 diabetes and are both necessary for the development of hyperglycemia. In both type 1 and type 2 diabetes, large, prospective clinical studies have shown a strong relation between time-averaged mean values of glycemia, measured as glycated hemoglobin (HbA1c), and vascular diabetic complications. These studies are the basis for the American Diabetes Association's current recommended treatment goal that HbA1c should be <7%. The measurement of the HbA1c concentration is considered the gold standard for assessing long-term glycemia; however, it does not reveal any information on the extent or frequency of blood glucose excursions, but provides an overall mean value only. Postprandial hyperglycemia occurs frequently in patients with diabetes receiving active treatment and can occur even when metabolic control is apparently good. Interventional studies indicate that reducing postmeal glucose excursions is as important as controlling fasting plasma glucose in persons with diabetes and impaired glucose tolerance. Evidence exists for a causal relation between postmeal glucose increases and microvascular and macrovascular outcomes; therefore, it is not surprising that treatment with different compounds that have specific effects on postprandial glucose regulation is accompanied by a significant improvement of many pathways supposed to be involved in diabetic complications, including oxidative stress, endothelial dysfunction, inflammation, and nuclear factor-kappaB activation. The goal of therapy should be to achieve glycemic status as near to normal as safely possible in all 3 components of glycemic control: HbA1c, fasting glucose, and postmeal glucose peak.

  18. Resting calcium influx in airway smooth muscle.

    PubMed

    Montaño, Luis M; Bazán-Perkins, Blanca

    2005-01-01

    Plasma membrane Ca2+ leak remains the most uncertain of the cellular Ca2+ regulation pathways. During passive Ca2+ influx in non-stimulated smooth muscle cells, basal activity of constitutive Ca2+ channels seems to be involved. In vascular smooth muscle, the 3 following Ca2+ entry pathways contribute to this phenomenon: (i) via voltage-dependent Ca2+ channels, (ii) receptor gated Ca2+ channels, and (iii) store operated Ca2+ channels, although, in airway smooth muscle it seems only 2 passive Ca2+ influx pathways are implicated, one sensitive to SKF 96365 (receptor gated Ca2+ channels) and the other to Ni2+ (store operated Ca2+ channels). Resting Ca2+ entry could provide a sufficient amount of Ca2+ and contribute to resting intracellular Ca2+ concentration ([Ca2+]i), maintenance of the resting membrane potential, myogenic tone, and sarcoplasmic reticulum-Ca2+ refilling. However, further research, especially in airway smooth muscle, is required to better explore the physiological role of this passive Ca2+ influx pathway as it could be involved in airway hyperresponsiveness.

  19. Putting the Squeeze on Airway Epithelia

    PubMed Central

    Park, Jin-Ah; Fredberg, Jeffrey J.

    2015-01-01

    Asthma is characterized by chronic inflammation, airway hyperresponsiveness, and progressive airway remodeling. The airway epithelium is known to play a critical role in the initiation and perpetuation of these processes. Here, we review how excessive epithelial stress generated by bronchoconstriction is sufficient to induce airway remodeling, even in the absence of inflammatory cells. PMID:26136543

  20. Serum leptin concentrations are not related to dietary patterns but are related to sex, age, body mass index, serum triacylglycerol, serum insulin, and plasma glucose in the US population

    PubMed Central

    Ganji, Vijay; Kafai, Mohammad R; McCarthy, Erin

    2009-01-01

    Background Leptin is known to play a role in food intake regulation. The aim of this study was to investigate the relation between serum leptin concentrations and dietary patterns and demographic, lifestyle, and health factors in the US population. Methods Data from the third National Health and Nutrition Examination Survey, 1988–1994 were used to study the association between fasting serum leptin and dietary patterns, sex, race-ethnicity, smoking, age, energy and alcohol intakes, body mass index (BMI), plasma glucose, serum triacylglycerol, and serum insulin in 4009 individuals. Factor analysis was used to derive three principle factors and these were labeled as Vegetable, Fruit, and Lean Meat, Western, and Mixed dietary patterns. Results Serum leptin concentrations were significantly higher in Vegetable, Fruit, and Lean Meat (8.5 fg/L) and Mixed patterns (8.0 fg/L) compared to Western pattern (6.29 fg/L) (P < 0.0001). When analysis was adjusted for confounding variables, no significant association was observed between serum leptin and dietary patterns (P = 0.22). Multivariate adjusted serum leptin concentrations were significantly associated with sex (higher in women than in men; β = -1.052; P < 0.0001), age (direct relation, β = 0.006, P < 0.0001), BMI, (direct relation, β = 0.082, P < 0.0001), fasting plasma glucose (inverse relation, β = -0.024, P = 0.0146), serum triacylglycerol (direct relation, β = 0.034, P = 0.0022), and serum insulin (direct relation, β = 0.003, P < 0.0001) but not with race-ethnicity (P = 0.65), smoking (P = 0.20), energy intake (P = 0.42), and alcohol intake (P = 0.73). Conclusion In this study, serum leptin was not independently associated with dietary patterns. Sex, age, BMI, serum triacylglycerol, plasma glucose, and serum insulin are independent predictors of serum leptin concentrations. PMID:19144201

  1. Airway complications after lung transplantation.

    PubMed

    Machuzak, Michael; Santacruz, Jose F; Gildea, Thomas; Murthy, Sudish C

    2015-01-01

    Airway complications after lung transplantation present a formidable challenge to the lung transplant team, ranging from mere unusual images to fatal events. The exact incidence of complications is wide-ranging depending on the type of event, and there is still evolution of a universal characterization of the airway findings. Management is also wide-ranging. Simple observation or simple balloon bronchoplasty is sufficient in many cases, but vigilance following more severe necrosis is required for late development of both anastomotic and nonanastomotic airway strictures. Furthermore, the impact of coexisting infection, rejection, and medical disease associated with high-level immunosuppression further complicates care.

  2. Gene Delivery to the Airway

    PubMed Central

    Keiser, Nicholas W.; Engelhardt, John F.

    2013-01-01

    This unit describes generation of and gene transfer to several commonly used airway models. Isolation and transduction of primary airway epithelial cells are first described. Next, the preparation of polarized airway epithelial monolayers is outlined. Transduction of these polarized cells is also described. Methods are presented for generation of tracheal xenografts as well as both ex vivo and in vivo gene transfer to these xenografts. Finally, a method for in vivo gene delivery to the lungs of rodents is included. Methods for evaluating transgene expression are given in the support protocols. PMID:23853081

  3. 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.

  4. A low frequency variant within the GWAS locus of MTNR1B affects fasting glucose concentrations: genetic risk is modulated by obesity.

    PubMed

    Been, L F; Hatfield, J L; Shankar, A; Aston, C E; Ralhan, S; Wander, G S; Mehra, N K; Singh, J R; Mulvihill, J J; Sanghera, D K

    2012-11-01

    Two common variants (rs1387153, rs10830963) in MTNR1B have been reported to have independent effects on fasting blood glucose (FBG) levels with increased risk to type 2 diabetes (T2D) in recent genome-wide association studies (GWAS). In this investigation, we report the association of these two variants, and an additional variant (rs1374645) within the GWAS locus of MTNR1B with FBG, 2h glucose, insulin resistance (HOMA IR), β-cell function (HOMA B), and T2D in our sample of Asian Sikhs from India. Our cohort comprised 2222 subjects [1201 T2D, 1021 controls]. None of these SNPs was associated with T2D in this cohort. Our data also could not confirm association of rs1387153 and rs10830963 with FBG phenotype. However, upon stratifying data according to body mass index (BMI) (low ≤ 25 kg/m(2) and high > 25 kg/m(2)) in normoglycemic subjects (n = 1021), the rs1374645 revealed a strong association with low FBG levels in low BMI group (β = -0.073, p = 0.002, Bonferroni p = 0.01) compared to the high BMI group (β = 0.015, p = 0.50). We also detected a strong evidence of interaction between rs1374645 and BMI with respect to FBG levels (p = 0.002). Our data provide new information about the significant impact of another MTNR1B variant on FBG levels that appears to be modulated by BMI. Future confirmation on independent datasets and functional studies will be required to define the role of this variant in fasting glucose variation.

  5. Sputum glucose and glycemic control in cystic fibrosis-related diabetes: a cross-sectional study.

    PubMed

    Van Sambeek, Lindsey; Cowley, Elise S; Newman, Dianne K; Kato, Roberta

    2015-01-01

    Cystic fibrosis-related diabetes affects up to half of cystic fibrosis patients and is associated with increased mortality and more frequent pulmonary exacerbations. However, it is unclear to what degree good glycemic control might mitigate these risks and clinical outcomes have not previously been studied in relation to glucose from the lower airways, the site of infection and CF disease progression. We initially hypothesized that diabetic cystic fibrosis patients with glycosylated hemoglobin (HbA(1c)) > 6.5% have worse pulmonary function, longer and more frequent exacerbations and also higher sputum glucose levels than patients with HbA(1c) ≤ 6.5% or cystic fibrosis patients without diabetes. To test this, we analyzed spontaneously expectorated sputum samples from 88 cystic fibrosis patients. The median sputum glucose concentration was 0.70 mM (mean, 4.75 mM; range, 0-64.6 mM). Sputum glucose was not correlated with age, sex, body mass index, diabetes diagnosis, glycemic control, exacerbation frequency or length, or pulmonary function. Surprisingly, sputum glucose was highest in subjects with normal glucose tolerance, suggesting the dynamics of glycemic control, sputum glucose and pulmonary infections are more complex than previously thought. Two-year mean HbA(1c) was positively correlated with the length of exacerbation admission (p < 0.01), and negatively correlated with measures of pulmonary function (p < 0.01). While total number of hospitalizations for exacerbations were not significantly different, subjects with an HbA(1c) > 6.5% were hospitalized on average 6 days longer than those with HbA(1c) ≤ 6.5% (p < 0.01). Current clinical care guidelines for cystic fibrosis-related diabetes target HbA(1c) ≤ 7% to limit long-term microvascular damage, but more stringent glycemic control (HbA(1c) ≤ 6.5%) may further reduce the short-term pulmonary complications.

  6. Predicted combustion product deposition in the human airway.

    PubMed

    Kaufman, J W; Scherer, P W; Yang, C C

    1996-12-31

    Fires involving modern polymeric materials produce toxic vapours and particles of widely varying composition and size depending on available oxygen and localized temperatures. Adverse health effects of inhaled combustion-generated particles depend on physiological interactions at the airway deposition site. The present work is a theoretical investigation into the importance of airway humidity and temperature profiles, initial particle size, particle size distribution and ionic concentration on airway particle deposition. A modified numerical model accounting for hygroscopic particle growth was used to predict airway deposition of 0.1-10.0 microm mass median aerodynamic diameter (MMAD) particles. Dynamic humidity profiles were generated with an unsteady state model of heat and water vapour transport. Results suggest that for hygroscopic particles < 2.0 microm, MMAD dynamic end-inspiratory humidity profiles produce up to 250% greater predicted nasopharyngeal deposition than steady state humidity profiles. Assuming combustion products are hygroscopic, these results also suggest that less pulmonary deposition will occur than previously predicted. In addition, higher upper airway concentrations of combustion products may have significant health consequences independent of pulmonary deposition patterns.

  7. Circulating Concentrations of Monocyte Chemoattractant Protein-1, Plasminogen Activator Inhibitor-1, and Soluble Leukocyte Adhesion Molecule-1 in Overweight/Obese Men and Women Consuming Fructose- or Glucose-Sweetened Beverages for 10 Weeks

    PubMed Central

    Cox, Chad L.; Stanhope, Kimber L.; Schwarz, Jean Marc; Graham, James L.; Hatcher, Bonnie; Griffen, Steven C.; Bremer, Andrew A.; Berglund, Lars; McGahan, John P.; Keim, Nancy L.

    2011-01-01

    Context: Results from animal studies suggest that consumption of large amounts of fructose can promote inflammation and impair fibrinolysis. Data describing the effects of fructose consumption on circulating levels of proinflammatory and prothrombotic markers in humans are unavailable. Objective: Our objective was to determine the effects of 10 wk of dietary fructose or glucose consumption on plasma concentrations of monocyte chemoattractant protein-1 (MCP-1), plasminogen activator inhibitor-1 (PAI-1), E-selectin, intercellular adhesion molecule-1, C-reactive protein, and IL-6. Design and Setting: This was a parallel-arm study with two inpatient phases (2 wk baseline, final 2 wk intervention), conducted in a clinical research facility, and an outpatient phase (8 wk) during which subjects resided at home. Participants: Participants were older (40–72 yr), overweight/obese (body mass index = 25–35 kg/m2) men (n = 16) and women (n = 15). Interventions: Participants consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 wk. Blood samples were collected at baseline and during the 10th week of intervention. Main Outcome Measures: Fasting concentrations of MCP-1 (P = 0.009), PAI-1 (P = 0.002), and E-selectin (P = 0.048) as well as postprandial concentrations of PAI-1 (P < 0.0001) increased in subjects consuming fructose but not in those consuming glucose. Fasting levels of C-reactive protein, IL-6, and intercellular adhesion molecule-1 were not changed in either group. Conclusions: Consumption of fructose for 10 wk leads to increases of MCP-1, PAI-1, and E-selectin. These findings suggest the possibility that fructose may contribute to the development of the metabolic syndrome via effects on proinflammatory and prothrombotic mediators. PMID:21956423

  8. United airway disease: current perspectives

    PubMed Central

    Giavina-Bianchi, Pedro; Aun, Marcelo Vivolo; Takejima, Priscila; Kalil, Jorge; Agondi, Rosana Câmara

    2016-01-01

    Upper and lower airways are considered a unified morphological and functional unit, and the connection existing between them has been observed for many years, both in health and in disease. There is strong epidemiologic, pathophysiologic, and clinical evidence supporting an integrated view of rhinitis and asthma: united airway disease in the present review. The term “united airway disease” is opportune, because rhinitis and asthma are chronic inflammatory diseases of the upper and lower airways, which can be induced by allergic or nonallergic reproducible mechanisms, and present several phenotypes. Management of rhinitis and asthma must be jointly carried out, leading to better control of both diseases, and the lessons of the Allergic Rhinitis and Its Impact on Asthma initiative cannot be forgotten. PMID:27257389

  9. Apoptosis and the Airway Epithelium

    PubMed Central

    White, Steven R.

    2011-01-01

    The airway epithelium functions as a barrier and front line of host defense in the lung. Apoptosis or programmed cell death can be elicited in the epithelium as a response to viral infection, exposure to allergen or to environmental toxins, or to drugs. While apoptosis can be induced via activation of death receptors on the cell surface or by disruption of mitochondrial polarity, epithelial cells compared to inflammatory cells are more resistant to apoptotic stimuli. This paper focuses on the response of airway epithelium to apoptosis in the normal state, apoptosis as a potential regulator of the number and types of epithelial cells in the airway, and the contribution of epithelial cell apoptosis in important airways diseases. PMID:22203854

  10. Extraglottic airway devices: A review

    PubMed Central

    Ramaiah, Ramesh; Das, Debasmita; Bhananker, Sanjay M; Joffe, Aaron M

    2014-01-01

    Extraglottic airway devices (EAD) have become an integral part of anesthetic care since their introduction into clinical practice 25 years ago and have been used safely hundreds of millions of times, worldwide. They are an important first option for difficult ventilation during both in-hospital and out-of-hospital difficult airway management and can be utilized as a conduit for tracheal intubation either blindly or assisted by another technology (fiberoptic endoscopy, lightwand). Thus, the EAD may be the most versatile single airway technique in the airway management toolbox. However, despite their utility, knowledge regarding specific devices and the supporting data for their use is of paramount importance to patient's safety. In this review, number of commercially available EADs are discussed and the reported benefits and potential pitfalls are highlighted. PMID:24741502

  11. Thixotropic solutions enhance viral-mediated gene transfer to airway epithelia.

    PubMed

    Seiler, Michael P; Luner, Paul; Moninger, Thomas O; Karp, Philip H; Keshavjee, Shaf; Zabner, Joseph

    2002-08-01

    Adenovirus-mediated gene transfer to airway epithelia is inefficient in part because its receptor is absent on the apical surface of the airways. Targeting adenovirus to other receptors, increasing the viral concentration, and even prolonging the incubation time with adenovirus vectors can partially overcome the lack of receptors and facilitate gene transfer. Unfortunately, mucociliary clearance would prevent prolonged incubation time in vivo. Thixotropic solutions (TS) are gels that upon a vigorous shearing force reversibly become liquid. We hypothesized that formulating recombinant adenoviruses in TS would decrease virus clearance and thus enhance gene transfer to the airway epithelia. We found that clearance of virus-sized fluorescent beads by human airway epithelia in vitro and by monkey trachea in vivo were markedly decreased when the beads were formulated in TS compared with phosphate-buffered saline (PBS). Adenovirus formulated in TS significantly increased adenovirus-mediated gene transfer of a reporter gene in human airway epithelia in vitro and in murine airway epithelia in vivo. Furthermore, an adenovirus encoding the cystic fibrosis transmembrane regulator (CFTR) gene (AdCFTR) formulated in TS was more efficient in correcting the chloride transport defect in cystic fibrosis airway epithelia than AdCFTR formulated in PBS. These data indicate a novel strategy to augment the efficiency of gene transfer to the airways that may be applicable to a number of different gene transfer vectors and could be of value in gene transfer to cystic fibrosis (CF) airway epithelia in vivo.

  12. Bioluminescence Imaging of Glucose in Tissue Surrounding Polyurethane and Glucose Sensor Implants

    PubMed Central

    Prichard, Heather L; Schroeder, Thies; Reichert, William M; Klitzman, Bruce

    2010-01-01

    Background The bioluminescence technique was used to quantify the local glucose concentration in the tissue surrounding subcutaneously implanted polyurethane material and surrounding glucose sensors. In addition, some implants were coated with a single layer of adipose-derived stromal cells (ASCs) because these cells improve the wound-healing response around biomaterials. Methods Control and ASC-coated implants were implanted subcutaneously in rats for 1 or 8 weeks (polyurethane) or for 1 week only (glucose sensors). Tissue biopsies adjacent to the implant were immediately frozen at the time of explant. Cryosections were assayed for glucose concentration profile using the bioluminescence technique. Results For the polyurethane samples, no significant differences in glucose concentration within 100 μm of the implant surface were found between bare and ASC-coated implants at 1 or 8 weeks. A glucose concentration gradient was demonstrated around the glucose sensors. For all sensors, the minimum glucose concentration of approximately 4 mM was found at the implant surface and increased with distance from the sensor surface until the glucose concentration peaked at approximately 7 mM at 100 μm. Then the glucose concentration decreased to 5.5–6.5 mM more than 100 μmm from the surface. Conclusions The ASC attachment to polyurethane and to glucose sensors did not change the glucose profiles in the tissue surrounding the implants. Although most glucose sensors incorporate a diffusion barrier to reduce the gradient of glucose and oxygen in the tissue, it is typically assumed that there is no steep glucose gradient around the sensors. However, a glucose gradient was observed around the sensors. A more complete understanding of glucose transport and concentration gradients around sensors is critical. PMID:20920425

  13. Circulating C1q complement/TNF-related protein (CTRP) 1, CTRP9, CTRP12 and CTRP13 concentrations in Type 2 diabetes mellitus: In vivo regulation by glucose

    PubMed Central

    Zhang, Man Man; Tan, Bee Kang; Chen, Jing

    2017-01-01

    Objectives The C1q complement/TNF-related protein (CTRP) superfamily, which includes the adipokine adiponectin, has been shown in animal models to have positive metabolic and cardiovascular effects. We sought to investigate circulating CTRP1, CTRP9, CTRP12 and CTRP13 concentrations in persons with type 2 diabetes mellitus (T2DM), with age and BMI matched controls, and to examine the effects of a 2 hour 75g oral glucose tolerance test (OGTT) on serum CTRP1, CTRP9, CTRP12 and CTRP13 levels in persons with T2DM. Design Cross-sectional study [newly diagnosed T2DM (n = 124) and control (n = 139) participants]. Serum CTRP1, CTRP9, CTRP12 and CTRP13 were measured by ELISA. Results Systolic and diastolic blood pressure, total cholesterol (TCH), Low-density lipoprotein (LDL)-cholesterol, triglycerides, TCH/High-density lipoprotein (HDL) ratio, triglycerides/HDL ratio, glucose, insulin, homeostatic model assessment–insulin resistance (HOMA-IR), C-reactive protein and endothelial lipase were significantly higher, whereas leptin and adiponectin were significantly lower in T2DM participants. Serum CTRP1 were significantly higher and CTRP12 significantly lower in T2DM participants. Age, diastolic blood pressure, glucose and CTRP12 were predictive of serum CTRP1; leptin was predictive of serum CTRP9; glucose and CTRP1 were predictive of serum CTRP12; endothelial lipase was predictive of serum CTRP13. Finally, serum CTRP1 were significantly higher and CTRP12 significantly lower in T2DM participants after a 2 hour 75g OGTT. Conclusions Our data supports CTRP1 and CTRP12 as potential novel biomarkers for the prediction and early diagnosis of T2DM. Furthermore, pharmacological agents that target CTRP1 and CTRP12 could represent a new strategy in the treatment of T2DM. PMID:28207876

  14. A new removable airway stent

    PubMed Central

    Amundsen, Tore; Sørhaug, Sveinung; Leira, Håkon Olav; Tyvold, Stig Sverre; Langø, Thomas; Hammer, Tommy; Manstad-Hulaas, Frode; Mattsson, Erney

    2016-01-01

    Background Malignant airway obstruction is a feared complication and will most probably occur more frequently in the future because of increasing cancer incidence and increased life expectancy in cancer patients. Minimal invasive treatment using airway stents represents a meaningful and life-saving palliation. We present a new removable airway stent for improved individualised treatment. Methods To our knowledge, the new airway stent is the world's first knitted and uncovered self-expanding metal stent, which can unravel and be completely removed. In an in vivo model using two anaesthetised and spontaneously breathing pigs, we deployed and subsequently removed the stents by unravelling the device. The procedures were executed by flexible bronchoscopy in an acute and a chronic setting – a ‘proof-of-principle’ study. Results The new stent was easily and accurately deployed in the central airways, and it remained fixed in its original position. It was easy to unravel and completely remove from the airways without clinically significant complications. During the presence of the stent in the chronic study, granulation tissue was induced. This tissue disappeared spontaneously with the removal. Conclusions The new removable stent functioned according to its purpose and unravelled easily, and it was completely removed without significant technical or medical complications. Induced granulation tissue disappeared spontaneously. Further studies on animals and humans are needed to define its optimal indications and future use. PMID:27608269

  15. Delayed feeding after hatch caused compensatory increases in blood glucose concentration in fed chicks from low but not high body weight lines.

    PubMed

    Zhao, Xiaoling; Sumners, Lindsay H; Gilbert, Elizabeth R; Siegel, Paul B; Zhang, Wei; Cline, Mark

    2014-03-01

    This experiment used 2 lines of chickens that have been selected 54 generations for either low (LWS) or high (HWS) 8-wk BW from the same founder population, sublines (HWR and LWR) in which selection was relaxed in generation 43 in the selected lines, and crosses (HL and LH) made from generation 54 of HWS and LWS. For 8-wk BW, the difference between lines LWS and HWS in generation 54 was approximately 10-fold, whereas for the relaxed contemporary lines they were approximately 7-fold. Three trials were designed to measure developmental, nutritional, and genetic aspects of blood glucose homeostasis during the first 2 wk posthatch. In trial 1, we measured BW, whole blood glucose (BG), and weights (relative to BW) of liver, pancreas, and yolk sac of chicks fed from day of hatch to d 15. In trial 2, we compared those traits in chicks feed-delayed 72 h posthatch and in chicks without feed delay. In trial 3, we evaluated the effect of a 16-h fast on BW and BG on d 3, 8, and 15. There were higher levels of BG in HWS than LWS, and males than females in the fed state. Delayed access to feed for 72 h after hatch was associated with a dramatic reduction in BG. Feeding triggered a compensatory response whereby LWS displayed greater BG but smaller pancreases (% BW; d 15), compared with the controls. There were maternal effects for BW in both fed and fasted states and the reciprocal crosses exhibited heterosis for BG in the fasted state. These results show that chickens selected for high or low BW differ in BG regulation during the early posthatch period.

  16. Human airway ciliary dynamics

    PubMed Central

    Thompson, Kristin; Knowles, Michael R.; Davis, C. William

    2013-01-01

    Airway cilia depend on precise changes in shape to transport the mucus gel overlying mucosal surfaces. The ciliary motion can be recorded in several planes using video microscopy. However, cilia are densely packed, and automated computerized systems are not available to convert these ciliary shape changes into forms that are useful for testing theoretical models of ciliary function. We developed a system for converting planar ciliary motions recorded by video microscopy into an empirical quantitative model, which is easy to use in validating mathematical models, or in examining ciliary function, e.g., in primary ciliary dyskinesia (PCD). The system we developed allows the manipulation of a model cilium superimposed over a video of beating cilia. Data were analyzed to determine shear angles and velocity vectors of points along the cilium. Extracted waveforms were used to construct a composite waveform, which could be used as a standard. Variability was measured as the mean difference in position of points on individual waveforms and the standard. The shapes analyzed were the end-recovery, end-effective, and fastest moving effective and recovery with mean (± SE) differences of 0.31(0.04), 0.25(0.06), 0.50(0.12), 0.50(0.10), μm, respectively. In contrast, the same measures for three different PCD waveforms had values far outside this range. PMID:23144323

  17. Airway Hydration and COPD

    PubMed Central

    Ghosh, Arunava; Boucher, R.C.; Tarran, Robert

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is one of the prevalent causes of worldwide mortality and encompasses two major clinical phenotypes, i.e., chronic bronchitis (CB) and emphysema. The most common cause of COPD is chronic tobacco inhalation. Research focused on the chronic bronchitic phenotype of COPD has identified several pathological processes that drive disease initiation and progression. For example, the lung’s mucociliary clearance (MCC) system performs the critical task of clearing inhaled pathogens and toxic materials from the lung. MCC efficiency is dependent on: (i) the ability of apical plasma membrane ion channels such as the cystic fibrosis transmembrane conductance regulator (CFTR) and the epithelial Na+ channel (ENaC) to maintain airway hydration; (ii) ciliary beating; and, (iii) appropriate rates of mucin secretion. Each of these components is impaired in CB and likely contributes to the mucus stasis/accumulation seen in CB patients. This review highlights the cellular components responsible for maintaining MCC and how this process is disrupted following tobacco exposure and with CB. We shall also discuss existing therapeutic strategies for the treatment of chronic bronchitis and how components of the MCC can be used as biomarkers for the evaluation of tobacco or tobacco-like-product exposure. PMID:26068443

  18. Efficacy of Surgical Airway Plasty for Benign Airway Stenosis

    PubMed Central

    Takahama, Makoto; Nakajima, Ryu; Kimura, Michitaka; Inoue, Hidetoshi; Yamamoto, Ryoji

    2015-01-01

    Background: Long-term patency is required during treatment for benign airway stenosis. This study investigated the effectiveness of surgical airway plasty for benign airway stenosis. Methods: Clinical courses of 20 patients, who were treated with surgical plasty for their benign airway stenosis, were retrospectively investigated. Results: Causes of stenosis were tracheobronchial tuberculosis in 12 patients, post-intubation stenosis in five patients, malacia in two patients, and others in one patient. 28 interventional pulmonology procedures and 20 surgical plasty were performed. Five patients with post-intubation stenosis and four patients with tuberculous stenosis were treated with tracheoplasty. Eight patients with tuberculous stenosis were treated with bronchoplasty, and two patients with malacia were treated with stabilization of the membranous portion. Anastomotic stenosis was observed in four patients, and one to four additional treatments were required. Performance status, Hugh–Jones classification, and ventilatory functions were improved after surgical plasty. Outcomes were fair in patients with tuberculous stenosis and malacia. However, efficacy of surgical plasty for post-intubation stenosis was not observed. Conclusion: Surgical airway plasty may be an acceptable treatment for tuberculous stenosis. Patients with malacia recover well after surgical plasty. There may be untreated patients with malacia who have the potential to benefit from surgical plasty. PMID:26567879

  19. Effects of dextromethorphan as add-on to sitagliptin on blood glucose and serum insulin concentrations in individuals with type 2 diabetes mellitus: a randomized, placebo-controlled, double-blinded, multiple crossover, single-dose clinical trial.

    PubMed

    Marquard, J; Stirban, A; Schliess, F; Sievers, F; Welters, A; Otter, S; Fischer, A; Wnendt, S; Meissner, T; Heise, T; Lammert, E

    2016-01-01

    In this clinical trial, we investigated the blood glucose (BG)-lowering effects of 30, 60 and 90 mg dextromethorphan (DXM) as well as 100 mg sitagliptin alone versus combinations of DXM and sitagliptin during an oral glucose tolerance test (OGTT) in 20 men with T2DM. The combination of 60 mg DXM plus 100 mg sitagliptin was observed to have the strongest effect in the OGTT. It lowered maximum BG concentrations and increased the baseline-adjusted area under the curve for serum insulin concentrations in the first 30 min of the OGTT (mean ± standard deviation 240 ± 47 mg/dl and 8.1 ± 6.1 mU/l/h, respectively) to a significantly larger extent than did 100 mg sitagliptin alone (254 ± 50 mg/dl and 5.8 ± 2.5 mU/l/h, respectively; p < 0.05) and placebo (272 ± 49 mg/dl and 3.9 ± 3.0 mU/l/h, respectively; p < 0.001). All study drugs were well tolerated, alone and in combination, without serious adverse events or hypoglycaemia. Long-term clinical trials are now warranted to investigate the potential of the combination of 30 or 60 mg DXM and dipeptidyl peptidase-4 inhibitors in the treatment of individuals with T2DM, in particular as preclinical studies have identified the β-cell protective properties of DXM.

  20. Airway management in emergency situations.

    PubMed

    Dörges, Volker

    2005-12-01

    Securing and monitoring the airway are among the key requirements of appropriate therapy in emergency patients. Failures to secure the airways can drastically increase morbidity and mortality of patients within a very short time. Therefore, the entire range of measures needed to secure the airway in an emergency, without intermediate ventilation and oxygenation, is limited to 30-40 seconds. Endotracheal intubation is often called the 'gold standard' for airway management in an emergency, but multiple failed intubation attempts do not result in maintaining oxygenation; instead, they endanger the patient by prolonging hypoxia and causing additional trauma to the upper airways. Thus, knowledge and availability of alternative procedures are also essential in every emergency setting. Given the great variety of techniques available, it is important to establish a well-planned, methodical protocol within the framework of an algorithm. This not only facilitates the preparation of equipment and the training of personnel, it also ensures efficient decision-making under time pressure. Most anaesthesia-related deaths are due to hypoxaemia when difficulty in securing the airway is encountered, especially in obstetrics during induction of anaesthesia for caesarean delivery. The most commonly occurring adverse respiratory events are failure to intubate, failure to recognize oesophageal intubation, and failure to ventilate. Thus, it is essential that every anaesthesiologist working on the labour and delivery ward is comfortable with the algorithm for the management of failed intubation. The algorithm for emergency airway management describing the sequence of various procedures has to be adapted to internal standards and to techniques that are available.

  1. A MEMS differential viscometric sensor for affinity glucose detection in continuous glucose monitoring

    NASA Astrophysics Data System (ADS)

    Huang, Xian; Li, Siqi; Davis, Erin; Leduc, Charles; Ravussin, Yann; Cai, Haogang; Song, Bing; Li, Dachao; Accili, Domenico; Leibel, Rudolph; Wang, Qian; Lin, Qiao

    2013-05-01

    Micromachined viscometric affinity glucose sensors have been previously demonstrated using vibrational cantilever and diaphragm. These devices featured a single glucose detection module that determines glucose concentrations through viscosity changes of glucose-sensitive polymer solutions. However, fluctuations in temperature and other environmental parameters might potentially affect the stability and reliability of these devices, creating complexity in their applications in subcutaneously implanted continuous glucose monitoring (CGM). To address these issues, we present a MEMS differential sensor that can effectively reject environmental disturbances while allowing accurate glucose detection. The sensor consists of two magnetically driven vibrating diaphragms situated inside microchambers filled with a boronic-acid based glucose-sensing solution and a reference solution insensitive to glucose. Glucose concentrations can be accurately determined by characteristics of the diaphragm vibration through differential capacitive detection. Our in vitro and preliminary in vivo experimental data demonstrate the potential of this sensor for highly stable subcutaneous CGM applications.

  2. Grepafloxacin inhibits tumor necrosis factor-alpha-induced interleukin-8 expression in human airway epithelial cells.

    PubMed

    Hashimoto, S; Matsumoto, K; Gon, Y; Maruoka, S; Hayashi, S; Asai, Y; Machino, T; Horie, T

    2000-01-01

    We examined the effect of grepafloxacin (GPFX), a new fluoroquinolone antimicrobial agent, on interleukin-8 (IL-8) expression in tumor necrosis factor-alpha (TNF-alpha)-stimulated human airway epithelial cells (AEC). GPFX inhibited IL-8 protein production as well as mRNA expression in a concentration-dependent manner (2.5 - 25 micro g/ml), but the inhibition of IL-8 expression by corresponding concentrations of GPFX to serum and airway lining fluids was not complete. We discuss the modulatory effect of GPFX on IL-8 production in the context of its efficacy on controlling chronic airway inflammatory diseases.

  3. One-Pot Biosynthesis of High-Concentration α-Glucose 1-Phosphate from Starch by Sequential Addition of Three Hyperthermophilic Enzymes.

    PubMed

    Zhou, Wei; You, Chun; Ma, Hongwu; Ma, Yanhe; Zhang, Y-H Percival

    2016-03-02

    α-Glucose 1-phosphate (G1P) is synthesized from 5% (w/v) corn starch and 1 M phosphate mediated by α-glucan phosphorylase (αGP) from the thermophilic bacterium Thermotoga maritima at pH 7.2 and 70 °C. To increase G1P yield from corn starch containing branched amylopectin, a hyper-thermostable isoamylase from Sulfolobus tokodaii was added for simultaneous starch gelatinization and starch-debranching hydrolysis at 85 °C and pH 5.5 before αGP use. The pretreatment of isoamylase increased G1P titer from 120 mM to 170 mM. To increase maltose and maltotriose utilization, the third thermostable enzyme, 4-glucanotransferase (4GT) from Thermococcus litoralis, was added during the late stage of G1P biotransformation, further increasing G1P titer to 200 mM. This titer is the highest G1P level obtained on starch or its derived products (maltodextrin and soluble starch). This study suggests that in vitro multienzyme biotransformation has an advantage of great engineering flexibility in terms of space and time compared with microbial fermentation.

  4. The Airway Microbiome at Birth

    PubMed Central

    Lal, Charitharth Vivek; Travers, Colm; Aghai, Zubair H.; Eipers, Peter; Jilling, Tamas; Halloran, Brian; Carlo, Waldemar A.; Keeley, Jordan; Rezonzew, Gabriel; Kumar, Ranjit; Morrow, Casey; Bhandari, Vineet; Ambalavanan, Namasivayam

    2016-01-01

    Alterations of pulmonary microbiome have been recognized in multiple respiratory disorders. It is critically important to ascertain if an airway microbiome exists at birth and if so, whether it is associated with subsequent lung disease. We found an established diverse and similar airway microbiome at birth in both preterm and term infants, which was more diverse and different from that of older preterm infants with established chronic lung disease (bronchopulmonary dysplasia). Consistent temporal dysbiotic changes in the airway microbiome were seen from birth to the development of bronchopulmonary dysplasia in extremely preterm infants. Genus Lactobacillus was decreased at birth in infants with chorioamnionitis and in preterm infants who subsequently went on to develop lung disease. Our results, taken together with previous literature indicating a placental and amniotic fluid microbiome, suggest fetal acquisition of an airway microbiome. We speculate that the early airway microbiome may prime the developing pulmonary immune system, and dysbiosis in its development may set the stage for subsequent lung disease. PMID:27488092

  5. Cystic Fibrosis Transmembrane Conductance Regulator in Sarcoplasmic Reticulum of Airway Smooth Muscle. Implications for Airway Contractility

    PubMed Central

    Cook, Daniel P.; Rector, Michael V.; Bouzek, Drake C.; Michalski, Andrew S.; Gansemer, Nicholas D.; Reznikov, Leah R.; Li, Xiaopeng; Stroik, Mallory R.; Ostedgaard, Lynda S.; Abou Alaiwa, Mahmoud H.; Thompson, Michael A.; Prakash, Y. S.; Krishnan, Ramaswamy; Meyerholz, David K.; Seow, Chun Y.

    2016-01-01

    Rationale: An asthma-like airway phenotype has been described in people with cystic fibrosis (CF). Whether these findings are directly caused by loss of CF transmembrane conductance regulator (CFTR) function or secondary to chronic airway infection and/or inflammation has been difficult to determine. Objectives: Airway contractility is primarily determined by airway smooth muscle. We tested the hypothesis that CFTR is expressed in airway smooth muscle and directly affects airway smooth muscle contractility. Methods: Newborn pigs, both wild type and with CF (before the onset of airway infection and inflammation), were used in this study. High-resolution immunofluorescence was used to identify the subcellular localization of CFTR in airway smooth muscle. Airway smooth muscle function was determined with tissue myography, intracellular calcium measurements, and regulatory myosin light chain phosphorylation status. Precision-cut lung slices were used to investigate the therapeutic potential of CFTR modulation on airway reactivity. Measurements and Main Results: We found that CFTR localizes to the sarcoplasmic reticulum compartment of airway smooth muscle and regulates airway smooth muscle tone. Loss of CFTR function led to delayed calcium reuptake following cholinergic stimulation and increased myosin light chain phosphorylation. CFTR potentiation with ivacaftor decreased airway reactivity in precision-cut lung slices following cholinergic stimulation. Conclusions: Loss of CFTR alters porcine airway smooth muscle function and may contribute to the airflow obstruction phenotype observed in human CF. Airway smooth muscle CFTR may represent a therapeutic target in CF and other diseases of airway narrowing. PMID:26488271

  6. Studies on Electrical behavior of Glucose using Impedance Spectroscopy

    NASA Astrophysics Data System (ADS)

    Juansah, Jajang; Yulianti, Wina

    2016-01-01

    In this work we report the electrical characteristics of glucose at different frequencies. We show the correlation between electrical properties (impedance, reactance, resistance and conductance) of glucose and glucose concentration. Electrical property measurements on glucose solution were performed in order to formulate the correlation. The measurements were conducted for frequencies between 50 Hz and 1 MHz. From the measurements, we developed a single-pole Cole-Cole graph as a function of glucose concentration.

  7. [Orthodontics and the upper airway].

    PubMed

    Cobo Plana, J; de Carlos Villafranca, F; Macías Escalada, E

    2004-03-01

    One of the general aims of orthodontic treatment and of the combination of orthodontics and orthognathic surgery is to achieve good occlusion and aesthetic improvement, especially in cases of severe dentoskeletal deformities. However, on many occasions, the parameters of the upper airways are not taken into account when the aims of conventional treatment are fulfilled. Patients with obstructive alterations during sleep represent for the orthodontist a type of patient who differs from the normal; for them, treatment should include the objective of improving oxygen saturation. Here, functional considerations should outweigh purely aesthetic ones. It is important, when making an orthodontic, surgical or combined diagnosis for a patient, to bear in mind the impact that treatment may have on the upper airways. Good aesthetics should never be achieved for some of our patients at the expense of diminishing the capacity of their upper airways.

  8. Airway hyperresponsiveness and inflammation induced by toluene diisocyanate in guinea pigs

    SciTech Connect

    Gordon, T.; Sheppard, D.; McDonald, D.M.; Distefano, S.; Scypinski, L.

    1985-11-01

    The authors examined the changes in airway responsiveness to increasing doses of an acetylcholine aerosol in anesthetized and ventilated guinea pigs 2, 6, or 24 h after exposure to 2 ppm toluene diisocyanate (TDI) or 2 h after exposure to air or 1 ppm TDI. The concentration of acetylcholine calculated to cause a 200% increase in RL was significantly lower for animals studied at 2 h (0.68%) or at 6 h (0.77%), but not at 24 h (2.39%), after TDI than for air animals (3.07%). The increase in airway responsiveness in the TDI-exposed animals was associated with histologic changes in the trachea and intrapulmonary airways. Exposure to 2 ppm TDI caused a patchy loss of cilia, shedding of epithelial cells into the airway lumen, and an influx of inflammatory cells into the trachea and other airways. In the lamina propria of the trachea, the concentration of extravascular polymorphonuclear leukocytes (PMN) was 13- to 26-fold greater in animals studied 2 or 6 h after exposure to 2 ppm TDI or at 2 h after 1 ppm TDI than in animals exposed to air. The concentration of PMN in the epithelium was significantly increased only in animals examined 2 h after 2 ppm TDI. These results indicate that a single exposure to TDI can cause an increase in airway responsiveness that is associated with epithelial injury and acute airway inflammation.

  9. A Common Missense Variant in the Glucokinase Regulatory Protein Gene (GCKR) Is Associated with Increased Plasma Triglyceride and C-Reactive Protein but Lower Fasting Glucose Concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 metaboli...

  10. Airway Assessment for Office Sedation/Anesthesia.

    PubMed

    Rosenberg, Morton B; Phero, James C

    2015-01-01

    Whenever a patient is about to receive sedation or general anesthesia, no matter what the technique, the preoperative assessment of the airway is one of the most important steps in ensuring patient safety and positive outcomes. This article, Part III in the series on airway management, is directed at the ambulatory office practice and focuses on predicting the success of advanced airway rescue techniques.

  11. Comments to Role of upper airway ultrasound in airway management.

    PubMed

    Lien, Wan-Ching

    2017-01-01

    Tracheal ultrasound can be an alternative diagnostic tool in airway management, besides traditional confirmatory methods such as capnography and auscultation. The standard image is a hyperechoic air-mucosa (A-M) interface with a reverberation artifact posteriorly (comet-tail artifact). If the second A-M interface appears, which we call a "double-tract sign," esophageal intubation is considered.

  12. Distal airway dysfunction identifies pulmonary inflammation in asymptomatic smokers

    PubMed Central

    Berger, Kenneth I.; Pradhan, Deepak R.; Goldring, Roberta M.; Oppenheimer, Beno W.; Rom, William N.

    2016-01-01

    Smoking induced inflammation leads to distal airway destruction. However, the relationship between distal airway dysfunction and inflammation remains unclear, particularly in smokers prior to the development of airway obstruction. Seven normal controls and 16 smokers without chronic obstructive pulmonary disease (COPD) were studied. Respiratory function was assessed using the forced oscillation technique (FOT). Abnormal FOT was defined as elevated resistance at 5 Hz (R5). Parameters reflecting distal lung function included frequency dependence of resistance (R5–20) and dynamic elastance (X5). Inflammation was quantified in concentrated bronchoalveolar lavage utilising cell count differential and cytokines expressed as concentration per mL epithelial lining fluid. All control subjects and seven smokers had normal R5. Nine smokers had elevated R5 with abnormal R5–20 and X5, indicating distal lung dysfunction. The presence of abnormal FOT was associated with two-fold higher lymphocyte and neutrophil counts (p<0.025) and with higher interleukin (IL)-8, eotaxin and fractalkine levels (p<0.01). Reactivity of R5–20 and X5 correlated with levels of IL-8, eotaxin, fractalkine, IL-12p70 and transforming growth factor-α (r>0.47, p<0.01). Distal airway dysfunction in smokers without COPD identifies the presence of distal lung inflammation that parallel reported observations in established COPD. These findings were not evident on routine pulmonary function testing and may allow the identification of smokers at risk of progression to COPD. PMID:27995132

  13. Distal airway dysfunction identifies pulmonary inflammation in asymptomatic smokers.

    PubMed

    Berger, Kenneth I; Pradhan, Deepak R; Goldring, Roberta M; Oppenheimer, Beno W; Rom, William N; Segal, Leopoldo N

    2016-10-01

    Smoking induced inflammation leads to distal airway destruction. However, the relationship between distal airway dysfunction and inflammation remains unclear, particularly in smokers prior to the development of airway obstruction. Seven normal controls and 16 smokers without chronic obstructive pulmonary disease (COPD) were studied. Respiratory function was assessed using the forced oscillation technique (FOT). Abnormal FOT was defined as elevated resistance at 5 Hz (R5). Parameters reflecting distal lung function included frequency dependence of resistance (R5-20) and dynamic elastance (X5). Inflammation was quantified in concentrated bronchoalveolar lavage utilising cell count differential and cytokines expressed as concentration per mL epithelial lining fluid. All control subjects and seven smokers had normal R5. Nine smokers had elevated R5 with abnormal R5-20 and X5, indicating distal lung dysfunction. The presence of abnormal FOT was associated with two-fold higher lymphocyte and neutrophil counts (p<0.025) and with higher interleukin (IL)-8, eotaxin and fractalkine levels (p<0.01). Reactivity of R5-20 and X5 correlated with levels of IL-8, eotaxin, fractalkine, IL-12p70 and transforming growth factor-α (r>0.47, p<0.01). Distal airway dysfunction in smokers without COPD identifies the presence of distal lung inflammation that parallel reported observations in established COPD. These findings were not evident on routine pulmonary function testing and may allow the identification of smokers at risk of progression to COPD.

  14. Oxidant-mediated ciliary dysfunction. Possible role in airway disease

    SciTech Connect

    Burman, W.J.; Martin, W.J. 2d.

    1986-03-01

    The effects of reactive species of oxygen on the airway are not well known. This study examined the effects of hydrogen peroxide (H2O2) on the structure and function of the airway epithelium. Tracheal rings were prepared from 200 g male rats. Damage to the airway epithelium was assayed by monitoring the ciliary beat frequency, the release of 51Cr, and histology. H2O2 at concentrations of 1.0 mM and above caused a very rapid decrease in ciliary beat frequency. After ten minutes' exposure to 1.0 mM, the ciliary beat frequency was 72 +/- 20 percent of control. Release of 51Cr was a less sensitive measure with significant release occurring after four hours of exposure to ciliotoxic concentrations of H2O2. Histologic changes were not evident within the experimental time period. All toxic effects of H2O2 were completely blocked by catalase. This study shows that H2O2 causes a rapid decline in ciliary activity and suggests that oxidant-mediated ciliary dysfunction could play a role in the pathogenesis of airway disease. The ciliary beat frequency provides a sensitive, physiologically relevant parameter for the in vitro study of these diseases.

  15. Feedback Regulation of Glucose Transporter Gene Transcription in Kluyveromyces lactis by Glucose Uptake

    PubMed Central

    Milkowski, C.; Krampe, S.; Weirich, J.; Hasse, V.; Boles, E.; Breunig, K. D.

    2001-01-01

    In the respirofermentative yeast Kluyveromyces lactis, only a single genetic locus encodes glucose transporters that can support fermentative growth. This locus is polymorphic in wild-type isolates carrying either KHT1 and KHT2, two tandemly arranged HXT-like genes, or RAG1, a low-affinity transporter gene that arose by recombination between KHT1 and KHT2. Here we show that KHT1 is a glucose-induced gene encoding a low-affinity transporter very similar to Rag1p. Kht2p has a lower Km (3.7 mM) and a more complex regulation. Transcription is high in the absence of glucose, further induced by low glucose concentrations, and repressed at higher glucose concentrations. The response of KHT1 and KHT2 gene regulation to high but not to low concentrations of glucose depends on glucose transport. The function of either Kht1p or Kht2p is sufficient to mediate the characteristic response to high glucose, which is impaired in a kht1 kht2 deletion mutant. Thus, the KHT genes are subject to mutual feedback regulation. Moreover, glucose repression of the endogenous β-galactosidase (LAC4) promoter and glucose induction of pyruvate decarboxylase were abolished in the kht1 kht2 mutant. These phenotypes could be partially restored by HXT gene family members from Saccharomyces cerevisiae. The results indicate that the specific responses to high but not to low glucose concentrations require a high rate of glucose uptake. PMID:11514503

  16. Growth of Carnobacterium divergens V41 and production of biogenic amines and divercin V41 in sterile cold-smoked salmon extract at varying temperatures, NaCl levels, and glucose concentrations.

    PubMed

    Connil, Nathalie; Plissoneau, Léon; Onno, Bernard; Pilet, Marie-France; Prévost, Hervé; Dousset, Xavier

    2002-02-01

    A complete factorial design 2(3) was used to study some aspects of Carnobacterium divergens V41 metabolism (growth, biogenic amine production, and divercin V41 production) in sterile cold-smoked salmon extract (SSE) at varying temperatures (3 to 9 degrees C), NaCl levels (2.5 to 6.5%), and glucose concentrations (2 to 6 g liter(-1)). The results showed that temperature and NaCl content were the most influential factors on growth parameters in SSE. Predictive models are suggested for the assessment of C. divergens lag time (t(lag)) and maximum specific growth rate (micro(max)) Among the biogenic amines studied, only tyramine was found to be produced by C. divergens in SSE. Furthermore, we showed that temperature, NaCl, and glucose variations did not greatly affect tyramine and divercin V41 production by the bacteria under the experimental conditions used. Indeed, divercin V41, a bacteriocin from C. divergens V41 that is highly active against some Listeria strains, was produced in SSE even under harsh culture conditions. Similarly, tyramine production in SSE was delayed at 3 degrees C but reached 35 microg ml(-1) in all experiments after 27 days of storage. However, this final tyramine concentration in SSE is low compared with the threshold values of 100 to 800 microg g(-1) reported as the potentially toxic dose in foods. Thus, we have found that C. divergens V41 is a promising strain for the biopreservation of refrigerated cold-smoked salmon.

  17. The Lung Microbiome and Airway Disease.

    PubMed

    Lynch, Susan V

    2016-12-01

    A growing body of literature has demonstrated relationships between the composition of the airway microbiota (mixed-species communities of microbes that exist in the respiratory tract) and critical features of immune response and pulmonary function. These studies provide evidence that airway inflammatory status and capacity for repair are coassociated with specific taxonomic features of the airway microbiome. Although directionality has yet to be established, the fact that microbes are known drivers of inflammation and tissue damage suggests that in the context of chronic inflammatory airway disease, the composition and, more importantly, the function, of the pulmonary microbiome represent critical factors in defining airway disease outcomes.

  18. Airway nerves: in vitro electrophysiology.

    PubMed

    Fox, Alyson

    2002-06-01

    Recording the activity of single airway sensory fibres or neuronal cell bodies in vitro has allowed detailed characterisation of fibre types and membrane properties. Fibre types can be identified by their conduction velocities and further studied by the application of drugs to their receptive field. C-fibres are sensitive to mechanical stimuli and a range of irritant chemicals (bradykinin, capsaicin, low pH, platelet-activating factor), whereas Adelta-fibres are relatively insensitive to chemical stimuli and appear to correlate to the rapidly adapting receptors identified in airways in vivo. Their site of origin also differs: upper airway C-fibres arise predominantly from the jugular ganglion and Adelta-fibres from the jugular and nodose ganglia. Intracellular recording from cell bodies in the ganglia has revealed a calcium-dependent potassium current common to many putative C-fibre cell bodies. This slow after hyperpolarisation current may be inhibited by stimuli that excite and sensitise C-fibres - this could be an important mechanism underlying the sensitisation of C-fibres in airway irritability.

  19. Effects of a meal rich in 1,3-diacylglycerol on postprandial cardiovascular risk factors and the glucose-dependent insulinotropic polypeptide in subjects with high fasting triacylglycerol concentrations.

    PubMed

    Shoji, Kentaro; Mizuno, Tomohito; Shiiba, Daisuke; Kawagoe, Tadanobu; Mitsui, Yuuki

    2012-03-14

    It was previously reported that compared to triacylglycerol (TAG) oil, diacylglycerol (DAG) oil improves postprandial lipid response. However, the effects of DAG oil on postprandial hyperglycemia and incretin response have not yet been determined. In this study, the effects of DAG oil on both postprandial hyperlipidemia and hyperglycemia and the response to the glucose-dependent insulinotropic polypeptide (GIP) were studied. This randomized, double-blind, crossover study analyzed data for 41 individuals with high fasting triacylglycerol concentrations. The subjects ingested test meals (30.3 g of protein, 18.6 g of fat, and 50.1 g of carbohydrate) containing 10 g of DAG oil (DAG meal) or TAG oil (TAG meal) after fasting for at least 12 h. Blood samples were collected prior to and 0.5, 2, 3, 4, and 6 h after ingestion of the test meal. Postprandial TAG concentrations were significantly lower after the DAG meal compared with the TAG meal. Postprandial TAG, insulin, and GIP concentrations were significantly lower after the DAG meal compared with the TAG meal in 26 subjects with fasting serum TAG levels between 1.36 and 2.83 mmol/L. DAG-oil-based meals, as a replacement for TAG oil, may provide cardiovascular benefits in high-risk individuals by limiting lipid and insulin excursions.

  20. Airway malacia in children with achondroplasia.

    PubMed

    Dessoffy, Kimberly E; Modaff, Peggy; Pauli, Richard M

    2014-02-01

    This study was undertaken to assess the frequency of airway malacia in infants and young children with achondroplasia, a population well known to be at risk for a variety of respiratory problems. We also wished to evaluate what, if any, contribution airway malacia makes to the complex respiratory issues that may be present in those with achondroplasia. Retrospective chart review of all infants and young children with achondroplasia who were assessed through the Midwest Regional Bone Dysplasia Clinics from 1985 through 2012 (n = 236) was completed. Records of comprehensive clinical examinations, polysomnographic assessments, and airway visualization were reviewed and abstracted using a data collection form. Analyses were completed comparing the group with and those without evidence for airway malacia. Thirteen of 236 patients (5.5%) were found to have airway malacia. Most of those affected had lower airway involvement (9/13). The presence of airway malacia was correlated with an increased occurrence of obstructive sleep apnea as well as need for oxygen supplementation, airway surgeries and tracheostomy placement. Although estimates of the frequency of airway malacia in the general population are limited, its frequency in children with achondroplasia appears to be much higher than any published general population estimate. The presence of airway malacia appears to confound other breathing abnormalities in this population and results in the need for more invasive airway treatments.

  1. Native Small Airways Secrete Bicarbonate

    PubMed Central

    Quinton, Paul M.

    2014-01-01

    Since the discovery of Cl− impermeability in cystic fibrosis (CF) and the cloning of the responsible channel, CF pathology has been widely attributed to a defect in epithelial Cl− transport. However, loss of bicarbonate (HCO3−) transport also plays a major, possibly more critical role in CF pathogenesis. Even though HCO3− transport is severely affected in the native pancreas, liver, and intestines in CF, we know very little about HCO3− secretion in small airways, the principle site of morbidity in CF. We used a novel, mini-Ussing chamber system to investigate the properties of HCO3− transport in native porcine small airways (∼ 1 mm φ). We assayed HCO3− transport across small airway epithelia as reflected by the transepithelial voltage, conductance, and equivalent short-circuit current with bilateral 25-mM HCO3− plus 125-mM NaGlu Ringer’s solution in the presence of luminal amiloride (10 μM). Under these conditions, because no major transportable anions other than HCO3− were present, we took the equivalent short-circuit current to be a direct measure of active HCO3− secretion. Applying selective agonists and inhibitors, we show constitutive HCO3− secretion in small airways, which can be stimulated significantly by β-adrenergic– (cAMP) and purinergic (Ca2+) -mediated agonists, independently. These results indicate that two separate components for HCO3− secretion, likely via CFTR- and calcium-activated chloride channel–dependent processes, are physiologically regulated for likely roles in mucus clearance and antimicrobial innate defenses of small airways. PMID:24224935

  2. Sarcoidosis of the upper and lower airways.

    PubMed

    Morgenthau, Adam S; Teirstein, Alvin S

    2011-12-01

    Sarcoidosis is a systemic granulomatous disease of undetermined etiology characterized by a variable clinical presentation and disease course. Although clinical granulomatous inflammation may occur within any organ system, more than 90% of sarcoidosis patients have lung disease. Sarcoidosis is considered an interstitial lung disease that is frequently characterized by restrictive physiologic dysfunction on pulmonary function tests. However, sarcoidosis also involves the airways (large and small), causing obstructive airways disease. It is one of a few interstitial lung diseases that affects the entire length of the respiratory tract - from the nose to the terminal bronchioles - and causes a broad spectrum of airways dysfunction. This article examines airway dysfunction in sarcoidosis. The anatomical structure of the airways is the organizational framework for our discussion. We discuss sarcoidosis involving the nose, sinuses, nasal passages, larynx, trachea, bronchi and small airways. Common complications of airways disease, such as, atelectasis, fibrosis, bullous leions, bronchiectasis, cavitary lesions and mycetomas, are also reviewed.

  3. Computational Fluid Dynamics Modeling of Bacillus anthracis Spore Deposition in Rabbit and Human Respiratory Airways

    SciTech Connect

    Kabilan, Senthil; Suffield, Sarah R.; Recknagle, Kurtis P.; Jacob, Rick E.; Einstein, Daniel R.; Kuprat, Andrew P.; Carson, James P.; Colby, Sean M.; Saunders, James H.; Hines, Stephanie; Teeguarden, Justin G.; Straub, Tim M.; Moe, M.; Taft, Sarah; Corley, Richard A.

    2016-09-30

    Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived from computed tomography (CT) or µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation-exhalation breathing conditions using average species-specific minute volumes. The highest exposure concentration was modeled in the rabbit based upon prior acute inhalation studies. For comparison, human simulation was also conducted at the same concentration. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the upper conducting airways compared to the human at the same air concentration of anthrax spores. As a result, higher particle deposition was predicted in the conducting airways and deep lung of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology.

  4. Airway remodeling in asthma: what really matters.

    PubMed

    Fehrenbach, Heinz; Wagner, Christina; Wegmann, Michael

    2017-03-01

    Airway remodeling is generally quite broadly defined as any change in composition, distribution, thickness, mass or volume and/or number of structural components observed in the airway wall of patients relative to healthy individuals. However, two types of airway remodeling should be distinguished more clearly: (1) physiological airway remodeling, which encompasses structural changes that occur regularly during normal lung development and growth leading to a normal mature airway wall or as an acute and transient response to injury and/or inflammation, which ultimately results in restoration of a normal airway structures; and (2) pathological airway remodeling, which comprises those structural alterations that occur as a result of either disturbed lung development or as a response to chronic injury and/or inflammation leading to persistently altered airway wall structures and function. This review will address a few major aspects: (1) what are reliable quantitative approaches to assess airway remodeling? (2) Are there any indications supporting the notion that airway remodeling can occur as a primary event, i.e., before any inflammatory process was initiated? (3) What is known about airway remodeling being a secondary event to inflammation? And (4), what can we learn from the different animal models ranging from invertebrate to primate models in the study of airway remodeling? Future studies are required addressing particularly pheno-/endotype-specific aspects of airway remodeling using both endotype-specific animal models and "endotyped" human asthmatics. Hopefully, novel in vivo imaging techniques will be further advanced to allow monitoring development, growth and inflammation of the airways already at a very early stage in life.

  5. Arginase enzymes in isolated airways from normal and nitric oxide synthase 2-knockout mice exposed to ovalbumin

    SciTech Connect

    Bratt, Jennifer M.; Franzi, Lisa M.; Linderholm, Angela L.; Last, Michael S.; Kenyon, Nicholas J. Last, Jerold A.

    2009-02-01

    Arginase has been suggested to compete with nitric oxide synthase (NOS) for their common substrate, L-arginine. To study the mechanisms underlying this interaction, we compared arginase expression in isolated airways and the consequences of inhibiting arginase activity in vivo with NO production, lung inflammation, and lung function in both C57BL/6 and NOS2 knockout mice undergoing ovalbumin-induced airway inflammation, a mouse model of asthma. Arginases I and II were measured by western blot in isolated airways from sensitized C57BL/6 mice exposed to ovalbumin aerosol. Physiological and biochemical responses - inflammation, lung compliance, airway hyperreactivity, exhaled NO concentration, arginine concentration - were compared with the responses of NOS2 knockout mice. NOS2 knockout mice had increased total cells in lung lavage, decreased lung compliance, and increased airway hyperreactivity. Both arginase I and arginase II were constitutively expressed in the airways of normal C57BL/6 mice. Arginase I was up-regulated approximately 8-fold in the airways of C57BL/6 mice exposed to ovalbumin. Expression of both arginase isoforms were significantly upregulated in NOS2 knockout mice exposed to ovalbumin, with about 40- and 4-fold increases in arginases I and II, respectively. Arginine concentration in isolated airways was not significantly different in any of the groups studied. Inhibition of arginase by systemic treatment of C57BL/6 mice with a competitive inhibitor, N{omega}-hydroxy-nor-L-arginine (nor-NOHA), significantly decreased the lung inflammatory response to ovalbumin in these animals. We conclude that NOS2 knockout mice are more sensitive to ovalbumin-induced airway inflammation and its sequelae than are C57BL/6 mice, as determined by increased total cells in lung lavage, decreased lung compliance, and increased airway hyperreactivity, and that these findings are strongly correlated with increased expression of both arginase isoforms in the airways of the

  6. Integrated care pathways for airway diseases (AIRWAYS-ICPs).

    PubMed

    Bousquet, J; Addis, A; Adcock, I; Agache, I; Agusti, A; Alonso, A; Annesi-Maesano, I; Anto, J M; Bachert, C; Baena-Cagnani, C E; Bai, C; Baigenzhin, A; Barbara, C; Barnes, P J; Bateman, E D; Beck, L; Bedbrook, A; Bel, E H; Benezet, O; Bennoor, K S; Benson, M; Bernabeu-Wittel, M; Bewick, M; Bindslev-Jensen, C; Blain, H; Blasi, F; Bonini, M; Bonini, S; Boulet, L P; Bourdin, A; Bourret, R; Bousquet, P J; Brightling, C E; Briggs, A; Brozek, J; Buhl, R; Bush, A; Caimmi, D; Calderon, M; Calverley, P; Camargos, P A; Camuzat, T; Canonica, G W; Carlsen, K H; Casale, T B; Cazzola, M; Cepeda Sarabia, A M; Cesario, A; Chen, Y Z; Chkhartishvili, E; Chavannes, N H; Chiron, R; Chuchalin, A; Chung, K F; Cox, L; Crooks, G; Crooks, M G; Cruz, A A; Custovic, A; Dahl, R; Dahlen, S E; De Blay, F; Dedeu, T; Deleanu, D; Demoly, P; Devillier, P; Didier, A; Dinh-Xuan, A T; Djukanovic, R; Dokic, D; Douagui, H; Dubakiene, R; Eglin, S; Elliot, F; Emuzyte, R; Fabbri, L; Fink Wagner, A; Fletcher, M; Fokkens, W J; Fonseca, J; Franco, A; Frith, P; Furber, A; Gaga, M; Garcés, J; Garcia-Aymerich, J; Gamkrelidze, A; Gonzales-Diaz, S; Gouzi, F; Guzmán, M A; Haahtela, T; Harrison, D; Hayot, M; Heaney, L G; Heinrich, J; Hellings, P W; Hooper, J; Humbert, M; Hyland, M; Iaccarino, G; Jakovenko, D; Jardim, J R; Jeandel, C; Jenkins, C; Johnston, S L; Jonquet, O; Joos, G; Jung, K S; Kalayci, O; Karunanithi, S; Keil, T; Khaltaev, N; Kolek, V; Kowalski, M L; Kull, I; Kuna, P; Kvedariene, V; Le, L T; Lodrup Carlsen, K C; Louis, R; MacNee, W; Mair, A; Majer, I; Manning, P; de Manuel Keenoy, E; Masjedi, M R; Melen, E; Melo-Gomes, E; Menzies-Gow, A; Mercier, G; Mercier, J; Michel, J P; Miculinic, N; Mihaltan, F; Milenkovic, B; Molimard, M; Momas, I; Montilla-Santana, A; Morais-Almeida, M; Morgan, M; N'Diaye, M; Nafti, S; Nekam, K; Neou, A; Nicod, L; O'Hehir, R; Ohta, K; Paggiaro, P; Palkonen, S; Palmer, S; Papadopoulos, N G; Papi, A; Passalacqua, G; Pavord, I; Pigearias, B; Plavec, D; Postma, D S; Price, D; Rabe, K F; Radier Pontal, F; Redon, J; Rennard, S; Roberts, J; Robine, J M; Roca, J; Roche, N; Rodenas, F; Roggeri, A; Rolland, C; Rosado-Pinto, J; Ryan, D; Samolinski, B; Sanchez-Borges, M; Schünemann, H J; Sheikh, A; Shields, M; Siafakas, N; Sibille, Y; Similowski, T; Small, I; Sola-Morales, O; Sooronbaev, T; Stelmach, R; Sterk, P J; Stiris, T; Sud, P; Tellier, V; To, T; Todo-Bom, A; Triggiani, M; Valenta, R; Valero, A L; Valiulis, A; Valovirta, E; Van Ganse, E; Vandenplas, O; Vasankari, T; Vestbo, J; Vezzani, G; Viegi, G; Visier, L; Vogelmeier, C; Vontetsianos, T; Wagstaff, R; Wahn, U; Wallaert, B; Whalley, B; Wickman, M; Williams, D M; Wilson, N; Yawn, B P; Yiallouros, P K; Yorgancioglu, A; Yusuf, O M; Zar, H J; Zhong, N; Zidarn, M; Zuberbier, T

    2014-08-01

    The objective of Integrated Care Pathways for Airway Diseases (AIRWAYS-ICPs) is to launch a collaboration to develop multi-sectoral care pathways for chronic respiratory diseases in European countries and regions. AIRWAYS-ICPs has strategic relevance to the European Union Health Strategy and will add value to existing public health knowledge by: 1) proposing a common framework of care pathways for chronic respiratory diseases, which will facilitate comparability and trans-national initiatives; 2) informing cost-effective policy development, strengthening in particular those on smoking and environmental exposure; 3) aiding risk stratification in chronic disease patients, using a common strategy; 4) having a significant impact on the health of citizens in the short term (reduction of morbidity, improvement of education in children and of work in adults) and in the long-term (healthy ageing); 5) proposing a common simulation tool to assist physicians; and 6) ultimately reducing the healthcare burden (emergency visits, avoidable hospitalisations, disability and costs) while improving quality of life. In the longer term, the incidence of disease may be reduced by innovative prevention strategies. AIRWAYSICPs was initiated by Area 5 of the Action Plan B3 of the European Innovation Partnership on Active and Healthy Ageing. All stakeholders are involved (health and social care, patients, and policy makers).

  7. Orienteering performance and ingestion of glucose and glucose polymers.

    PubMed

    Kujala, U M; Heinonen, O J; Kvist, M; Kärkkäinen, O P; Marniemi, J; Niittymäki, K; Havas, E

    1989-06-01

    The benefit of glucose polymer ingestion in addition to 2.5 per cent glucose before and during a prolonged orienteering competition was studied. The final time in the competition in the group ingesting 2.5 per cent glucose (group G, n = 10) was 113 min 37 s +/- 8 min 11 s, and in the group which had additionally ingested glucose polymer (group G + GP, n = 8) 107 min 18s +/- 4 min 41 s (NS). One fifth (21 per cent) of the time difference between the two groups was due to difference in orienteering errors. Group G + GP orienteered the last third of the competition faster than group G (p less than 0.05). The time ratio between the last third of the competition and the first third of the competition was lower in group G + GP than in group G (p less than 0.05). After the competition, there was statistically insignificant tendency to higher serum glucose and lower serum free fatty acid concentrations in group G + GP, and serum insulin concentration was higher in group G + GP than in group G (p less than 0.05). Three subjects reported that they exhausted during the competition. These same three subjects had the lowest serum glucose concentrations after the competition (2.9 mmol.1(-1), 2.9 mmol.1(-1), 3.5 mmol.1(-1] and all of them were from group G. It is concluded that glucose polymer syrup ingestion is beneficial for prolonged psychophysical performance.

  8. Generation of Pig Airways using Rules Developed from the Measurements of Physical Airways

    PubMed Central

    Azad, Md Khurshidul; Mansy, Hansen A.

    2017-01-01

    Background A method for generating bronchial tree would be helpful when constructing models of the tree for benchtop experiments as well as for numerical modeling of flow or sound propagation in the airways. Early studies documented the geometric details of the human airways that were used to develop methods for generating human airway tree. However, methods for generating animal airway tree are scarcer. Earlier studies suggested that the morphology of animal airways can be significantly different from that of humans. Hence, using algorithms for the human airways may not be accurate in generating models of animal airway geometry. Objective The objective of this study is to develop an algorithm for generating pig airway tree based on the geometric details extracted from the physical measurements. Methods In the current study, measured values of branch diameters, lengths and bifurcation angles and rotation of bifurcating planes were used to develop an algorithm that is capable of generating a realistic pig airway tree. Results The generation relations between parent and daughter branches were found to follow certain trends. The diameters and the length of different branches were dependent on airway generations while the bifurcation angles were primarily dependent on bifurcation plane rotations. These relations were sufficient to develop rules for generating a model of the pig large airways. Conclusion The results suggested that the airway tree generated from the algorithm can provide an approximate geometric model of pig airways for computational and benchtop studies. PMID:28255517

  9. Mathematical modeling on experimental protocol of glucose adjustment for non-invasive blood glucose sensing

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Min, Xiaolin; Zou, Da; Xu, Kexin

    2012-03-01

    Currently, blood glucose concentration levels from OGTT(Oral Glucose Tolerance Test) results are used to build PLS model in noninvasive blood glucose sensing by Near-Infrared(NIR) Spectroscopy. However, the univocal dynamic change trend of blood glucose concentration based on OGTT results is not various enough to provide comprehensive data to make PLS model robust and accurate. In this talk, with the final purpose of improving the stability and accuracy of the PLS model, we introduced an integrated minimal model(IMM) of glucose metabolism system. First, by adjusting parameters, which represent different metabolism characteristics and individual differences, comparatively ideal mediation programs to different groups of people, even individuals were customized. Second, with different glucose input types(oral method, intravenous injection, or intravenous drip), we got various changes of blood glucose concentration. And by studying the adjustment methods of blood glucose concentration, we would thus customize corresponding experimental protocols of glucose adjustment to different people for noninvasive blood glucose concentration and supply comprehensive data for PLS model.

  10. Recent trends in airway management

    PubMed Central

    Karlik, Joelle; Aziz, Michael

    2017-01-01

    Tracheal intubation remains a life-saving procedure that is typically not difficult for experienced providers in routine conditions. Unfortunately, difficult intubation remains challenging to predict and intubation conditions may make the event life threatening. Recent technological advances aim to further improve the ease, speed, safety, and success of intubation but have not been fully investigated. Video laryngoscopy, though proven effective in the difficult airway, may result in different intubation success rates in various settings and in different providers’ hands. The rescue surgical airway remains a rarely used but critical skill, and research continues to investigate optimal techniques. This review highlights some of the new thoughts and research on these important topics. PMID:28299194

  11. Simulation on how to customize glucose adjustment method for non-invasive blood glucose sensing by NIRS

    NASA Astrophysics Data System (ADS)

    Min, Xiaolin; Jiang, Jingying; Zou, Da; Liu, Rong; Xu, Kexin

    2013-02-01

    Previous studies have shown the limitations of taking OGTT (Oral Glucose Tolerance Test) as the glucose adjustment protocol for non-invasive blood glucose sensing. Previous studies built a mathematical model of glucose metabolism system-IMM (the Integrated Minimal Model) to probe other available adjustment methods. In this talk, a further study would be focused on more detailed combination options of different glucose input types for glucose adjustment projects in non-invasive blood glucose sensing. And predictive models of blood glucose concentration have been established by means of partial least squares (PLS) method, which could be used to evaluate the quality of different glucose adjustment options. Results of PLS modeling suggested that predictive models under combined glucose input types, compared with OGTT, show a great enhancement in the stability. This would finally improve the precision of non-invasive blood glucose sensing.

  12. Ketones suppress brain glucose consumption.

    PubMed

    LaManna, Joseph C; Salem, Nicolas; Puchowicz, Michelle; Erokwu, Bernadette; Koppaka, Smruta; Flask, Chris; Lee, Zhenghong

    2009-01-01

    The brain is dependent on glucose as a primary energy substrate, but is capable of utilizing ketones such as beta-hydroxybutyrate (beta HB) and acetoacetate (AcAc), as occurs with fasting, prolonged starvation or chronic feeding of a high fat/low carbohydrate diet (ketogenic diet). In this study, the local cerebral metabolic rate of glucose consumption (CMRglu; microM/min/100g) was calculated in the cortex and cerebellum of control and ketotic rats using Patlak analysis. Rats were imaged on a rodent PET scanner and MRI was performed on a 7-Tesla Bruker scanner for registration with the PET images. Plasma glucose and beta HB concentrations were measured and 90-minute dynamic PET scans were started simultaneously with bolus injection of 2-Deoxy-2[18F]Fluoro-D-Glucose (FDG). The blood radioactivity concentration was automatically sampled from the tail vein for 3 min following injection and manual periodic blood samples were taken. The calculated local CMRGlu decreased with increasing plasma BHB concentration in the cerebellum (CMRGlu = -4.07*[BHB] + 61.4, r2 = 0.3) and in the frontal cortex (CMRGlu = -3.93*[BHB] + 42.7, r2 = 0.5). These data indicate that, under conditions of ketosis, glucose consumption is decreased in the cortex and cerebellum by about 10% per each mM of plasma ketone bodies.

  13. Partial airway obstruction following manufacturing defect in laryngeal mask airway (Laryngeal Mask Silken™).

    PubMed

    Jangra, Kiran; Malhotra, Surender Kumar; Saini, Vikas

    2014-10-01

    Laryngeal mask (LM) airway is commonly used for securing airway in day-care surgeries. Various problems have been described while using LM airway. Out of those, mechanical obstruction causing airway compromise is most common. Here, we describe a case report of 4-year-old child who had partial upper airway obstruction due to LM manufacturer's defect. There was a silicon band in upper one-third of shaft of LM airway. This band was made up of the same material as that of LM airway so it was not identifiable on external inspection of transparent shaft. We suggest that such as non-transparent laryngeal mask, a transparent LM airway should also be inspected looking inside the lumen with naked eyes or by using a probe to rule out any manufacturing defect before its insertion.

  14. Glucose biosensor based on nanocomposite films of CdTe quantum dots and glucose oxidase.

    PubMed

    Li, Xinyu; Zhou, Yunlong; Zheng, Zhaozhu; Yue, Xiuli; Dai, Zhifei; Liu, Shaoqin; Tang, Zhiyong

    2009-06-02

    A blood glucose sensor has been developed based on the multilayer films of CdTe semiconductor quantum dots (QDs) and glucose oxidase (GOD) by using the layer-by-layer assembly technique. When the composite films were contacted with glucose solution, the photoluminescence of QDs in the films was quickly quenched because the enzyme-catalyzed reaction product (H2O2) of GOD and glucose gave rise to the formation of surface defects on QDs. The quenching rate was a function of the concentration of glucose. The linear range and sensitivity for glucose determination could be adjusted by controlling the layers of QDs and GOD. The biosensor was used to successfully determine the concentration of blood glucose in real serum samples without sample pretreatment and exhibited satisfactory reproducibility and accuracy.

  15. Glucose-responsive hydrogel electrode for biocompatible glucose transistor.

    PubMed

    Kajisa, Taira; Sakata, Toshiya

    2017-01-01

    In this paper, we propose a highly sensitive and biocompatible glucose sensor using a semiconductor-based field effect transistor (FET) with a functionalized hydrogel. The principle of the FET device contributes to the easy detection of ionic charges with high sensitivity, and the hydrogel coated on the electrode enables the specific detection of glucose with biocompatibility. The copolymerized hydrogel on the Au gate electrode of the FET device is optimized by controlling the mixture ratio of biocompatible 2-hydroxyethylmethacrylate (HEMA) as the main monomer and vinylphenylboronic acid (VPBA) as a glucose-responsive monomer. The gate surface potential of the hydrogel FETs shifts in the negative direction with increasing glucose concentration from 10 μM to 40 mM, which results from the increase in the negative charges on the basis of the diol-binding of PBA derivatives with glucose molecules in the hydrogel. Moreover, the hydrogel coated on the gate suppresses the signal noise caused by the nonspecific adsorption of proteins such as albumin. The hydrogel FET can serve as a highly sensitive and biocompatible glucose sensor in in vivo or ex vivo applications such as eye contact lenses and sheets adhering to the skin.

  16. Glucose-responsive hydrogel electrode for biocompatible glucose transistor

    PubMed Central

    Kajisa, Taira; Sakata, Toshiya

    2017-01-01

    Abstract In this paper, we propose a highly sensitive and biocompatible glucose sensor using a semiconductor-based field effect transistor (FET) with a functionalized hydrogel. The principle of the FET device contributes to the easy detection of ionic charges with high sensitivity, and the hydrogel coated on the electrode enables the specific detection of glucose with biocompatibility. The copolymerized hydrogel on the Au gate electrode of the FET device is optimized by controlling the mixture ratio of biocompatible 2-hydroxyethylmethacrylate (HEMA) as the main monomer and vinylphenylboronic acid (VPBA) as a glucose-responsive monomer. The gate surface potential of the hydrogel FETs shifts in the negative direction with increasing glucose concentration from 10 μM to 40 mM, which results from the increase in the negative charges on the basis of the diol-binding of PBA derivatives with glucose molecules in the hydrogel. Moreover, the hydrogel coated on the gate suppresses the signal noise caused by the nonspecific adsorption of proteins such as albumin. The hydrogel FET can serve as a highly sensitive and biocompatible glucose sensor in in vivo or ex vivo applications such as eye contact lenses and sheets adhering to the skin. PMID:28179956

  17. Airway surface liquid volume expansion induces rapid changes in amiloride-sensitive Na+ transport across upper airway epithelium-Implications concerning the resolution of pulmonary edema

    PubMed Central

    Azizi, Fouad; Arredouani, Abdelilah; Mohammad, Ramzi M

    2015-01-01

    During airway inflammation, airway surface liquid volume (ASLV) expansion may result from the movement of plasma proteins and excess liquid into the airway lumen due to extravasation and elevation of subepithelial hydrostatic pressure. We previously demonstrated that elevation of submucosal hydrostatic pressure increases airway epithelium permeability resulting in ASLV expansion by 500 μL cm−2 h−1. Liquid reabsorption by healthy airway epithelium is regulated by active Na+ transport at a rate of 5 μL cm−2 h−1. Thus, during inflammation the airway epithelium may be submerged by a large volume of luminal liquid. Here, we have investigated the mechanism by which ASLV expansion alters active epithelial Na+ transport, and we have characterized the time course of the change. We used primary cultures of tracheal airway epithelium maintained under air interface (basal ASLV, depth is 7 ± 0.5 μm). To mimic airway flooding, ASLV was expanded to a depth of 5 mm. On switching from basal to expanded ASLV conditions, short-circuit current (Isc, a measure of total transepithelial active ion transport) declined by 90% with a half-time (t1/2) of 1 h. 24 h after the switch, there was no significant change in ATP concentration nor in the number of functional sodium pumps as revealed by [3H]-ouabain binding. However, amiloride-sensitive uptake of 22Na+ was reduced by 70% upon ASLV expansion. This process is reversible since after returning cells back to air interface, Isc recovered with a t1/2 of 5–10 h. These results may have important clinical implications concerning the development of Na+ channels activators and resolution of pulmonary edema. PMID:26333829

  18. Upper-airway cough syndrome with latent eosinophilic bronchitis.

    PubMed

    Yu, Li; Wei, Weili; Wang, Lan; Huang, Yang; Shi, Cuiqin; Lü, Hanjing; Qiu, Zhongmin

    2010-01-01

    Upper-airway cough syndrome often coexists with other diseases that elicit chronic cough. However, the concomitant conditions are not always relevant to chronic cough, which complicates the cause diagnosis of chronic cough. The objective of this study was to explore the diagnosis and clinical implication of upper-airway cough syndrome with latent eosinophilic bronchitis. Eleven patients with upper-airway cough syndrome and latent eosinophilic bronchitis were retrospectively analyzed for their clinical manifestations, changes of eosinophilia in induced sputum, and cough threshold with capsaicin defined as capsaicin concentration that elicits two or more coughs (C2) and five or more coughs (C5) between pretreatment and post-treatment. All patients reported a history of allergic rhinitis, showed persistent dry cough or small amounts of viscid sputum with a time course of 2-60 months (median = 7 months), and presented with symptoms and signs of rhinitis, normal lung function, and airway responsiveness. Initial eosinophil percentage in induced sputum was 3.5-8.0%. Cough disappeared after 2-5 (3 +/- 1) weeks of only oral antihistamine. With successful treatment, cough threshold C2 increased from 1.73 +/- 1.45 to 4.43 +/- 4.50 micromol/L (t = 2.64, P = 0.025) and C5 increased from 2.79 +/- 2.16 to 10.10 +/- 8.22 micromol/L (t = 3.10, P = 0.011). However, there was no significant change of eosinophil percentage in induced sputum (4.8 +/- 1.5% vs. 4.4 +/- 1.4%, t = 0.84, P = 0.427). Upper-airway cough syndrome with latent eosinophilic bronchitis is a unique condition. The recognition of the entity may avoid unnecessary use of corticosteroids.

  19. Nucleotide release provides a mechanism for airway surface liquid homeostasis.

    PubMed

    Lazarowski, Eduardo R; Tarran, Robert; Grubb, Barbara R; van Heusden, Catharina A; Okada, Seiko; Boucher, Richard C

    2004-08-27

    Nucleotides within the airway surface liquid (ASL) regulate airway epithelial ion transport rates by Ca(2+) -and protein kinase C-dependent mechanisms via activation of specific P2Y receptors. Extracellular adenine nucleotides also serve as precursors for adenosine, which promotes cyclic AMP-mediated activation of the cystic fibrosis transmembrane regulator chloride channel via A(2b) adenosine receptors. A biological role for extracellular ATP in ASL volume homeostasis has been suggested by the demonstration of regulated ATP release from airway epithelia. However, nucleotide hydrolysis at the airway surface makes it difficult to assess the magnitude of ATP release and the relative abundance of adenyl purines and, hence, to define their biological functions. We have combined ASL microsampling and high performance liquid chromatography analysis of fluorescent 1,N(6)-ethenoadenine derivatives to measure adenyl purines in ASL. We found that adenosine, AMP, and ADP accumulated in high concentrations relative to ATP within the ASL covering polarized primary human normal or cystic fibrosis airway epithelial cells. By using immortalized epithelial cell monolndogenayers that eously express a luminal A(2b) adenosine receptor, we found that basal as well asforskolin-promoted cyclic AMP production was reduced by exogenous adenosine deaminase, suggesting that A(2b) receptors sense endogenous adenosine within the ASL. The physiological role of adenosine was further established by illustrating that adenosine removal or inhibition of adenosine receptors in primary cultures impaired ASL volume regulation. Our data reveal a complex pattern of nucleotides/nucleosides in ASL under resting conditions and suggest that adenosine may play a key role in regulating ASL volume homeostasis.

  20. Nucleotide Release Provides a Mechanism for Airway Surface Liquid Homeostasis*

    PubMed Central

    Lazarowski, Eduardo R.; Tarran, Robert; Grubb, Barbara R.; van Heusden, Catharina A.; Okada, Seiko; Boucher, Richard C.

    2010-01-01

    Nucleotides within the airway surface liquid (ASL) regulate airway epithelial ion transport rates by Ca2+- and protein kinase C-dependent mechanisms via activation of specific P2Y receptors. Extracellular adenine nucleotides also serve as precursors for adenosine, which promotes cyclic AMP-mediated activation of the cystic fibrosis transmembrane regulator chloride channel via A2b adenosine receptors. A biological role for extracellular ATP in ASL volume homeostasis has been suggested by the demonstration of regulated ATP release from airway epithelia. However, nucleotide hydrolysis at the airway surface makes it difficult to assess the magnitude of ATP release and the relative abundance of adenyl purines and, hence, to define their biological functions. We have combined ASL microsampling and high performance liquid chromatography analysis of fluorescent 1,N6-ethenoadenine derivatives to measure adenyl purines in ASL. We found that adenosine, AMP, and ADP accumulated in high concentrations relative to ATP within the ASL covering polarized primary human normal or cystic fibrosis airway epithelial cells. By using immortalized epithelial cell monolayers that endogenously express a luminal A2b adenosine receptor, we found that basal as well as forskolin-promoted cyclic AMP production was reduced by exogenous adenosine deaminase, suggesting that A2b receptors sense endogenous adenosine within the ASL. The physiological role of adenosine was further established by illustrating that adenosine removal or inhibition of adenosine receptors in primary cultures impaired ASL volume regulation. Our data reveal a complex pattern of nucleotides/nucleosides in ASL under resting conditions and suggest that adenosine may play a key role in regulating ASL volume homeostasis. PMID:15210701

  1. Colonization of CF patients' upper airways with S. aureus contributes more decisively to upper airway inflammation than P. aeruginosa.

    PubMed

    Janhsen, Wibke Katharina; Arnold, Christin; Hentschel, Julia; Lehmann, Thomas; Pfister, Wolfgang; Baier, Michael; Böer, Klas; Hünniger, Kerstin; Kurzai, Oliver; Hipler, Uta-Christina; Mainz, Jochen Georg

    2016-10-01

    In cystic fibrosis (CF) patients' airways, inflammatory processes decisively contribute to remodeling and pulmonary destruction. The aims of this study were to compare upper airway (UAW) inflammation in the context of Staphylococcus aureus and Pseudomonas aeruginosa colonization in a longitudinal setting, and to examine further factors influencing UAW inflammation. Therefore, we analyzed soluble inflammatory mediators in noninvasively obtained nasal lavage (NL) of CF patients together with microbiology, medication, and relevant clinical parameters. NL, applying 10 mL of isotonic saline per nostril, was serially performed in 74 CF patients (326 samples). Concentrations of the inflammatory mediators' interleukin (IL)-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-9, and its anti-protease TIMP-1 were quantified by bead-based multiplexed assay, neutrophil elastase (NE) via ELISA. Culture-based microbiology of the upper and lower airways (LAW), as well as serological and clinical findings, were compiled. Our results indicate that UAW colonization with S. aureus significantly impacts the concentration of all measured inflammatory mediators in NL fluid except TIMP-1, whereas these effects were not significant for P. aeruginosa. Patients with S. aureus colonization of both the UAW and LAW showed significantly increased concentrations of IL-1β, IL-6, IL-8, MMP-9, and slightly elevated concentrations of NE in NL fluid compared to non-colonized patients. This work elaborates a survey on S. aureus' virulence factors that may contribute to this underestimated pathology. Serial assessment of epithelial lining fluid by NL reveals that colonization of the UAW with S. aureus contributes more to CF airway inflammatory processes than hitherto expected.

  2. Method for 3D Airway Topology Extraction

    PubMed Central

    Grothausmann, Roman; Kellner, Manuela; Heidrich, Marko; Lorbeer, Raoul-Amadeus; Ripken, Tammo; Meyer, Heiko; Kuehnel, Mark P.; Ochs, Matthias; Rosenhahn, Bodo

    2015-01-01

    In lungs the number of conducting airway generations as well as bifurcation patterns varies across species and shows specific characteristics relating to illnesses or gene variations. A method to characterize the topology of the mouse airway tree using scanning laser optical tomography (SLOT) tomograms is presented in this paper. It is used to test discrimination between two types of mice based on detected differences in their conducting airway pattern. Based on segmentations of the airways in these tomograms, the main spanning tree of the volume skeleton is computed. The resulting graph structure is used to distinguish between wild type and surfactant protein (SP-D) deficient knock-out mice. PMID:25767561

  3. Automated Lobe-Based Airway Labeling

    PubMed Central

    Gu, Suicheng; Wang, Zhimin; Siegfried, Jill M.; Wilson, David; Bigbee, William L.; Pu, Jiantao

    2012-01-01

    Regional quantitative analysis of airway morphological abnormalities is of great interest in lung disease investigation. Considering that pulmonary lobes are relatively independent functional unit, we develop and test a novel and efficient computerized scheme in this study to automatically and robustly classify the airways into different categories in terms of pulmonary lobe. Given an airway tree, which could be obtained using any available airway segmentation scheme, the developed approach consists of four basic steps: (1) airway skeletonization or centerline extraction, (2) individual airway branch identification, (3) initial rule-based airway classification/labeling, and (4) self-correction of labeling errors. In order to assess the performance of this approach, we applied it to a dataset consisting of 300 chest CT examinations in a batch manner and asked an image analyst to subjectively examine the labeled results. Our preliminary experiment showed that the labeling accuracy for the right upper lobe, the right middle lobe, the right lower lobe, the left upper lobe, and the left lower lobe is 100%, 99.3%, 99.3%, 100%, and 100%, respectively. Among these, only two cases are incorrectly labeled due to the failures in airway detection. It takes around 2 minutes to label an airway tree using this algorithm. PMID:23093951

  4. Anatomic Optical Coherence Tomography of Upper Airways

    NASA Astrophysics Data System (ADS)

    Chin Loy, Anthony; Jing, Joseph; Zhang, Jun; Wang, Yong; Elghobashi, Said; Chen, Zhongping; Wong, Brian J. F.

    The upper airway is a complex and intricate system responsible for respiration, phonation, and deglutition. Obstruction of the upper airways afflicts an estimated 12-18 million Americans. Pharyngeal size and shape are important factors in the pathogenesis of airway obstructions. In addition, nocturnal loss in pharyngeal muscular tone combined with high pharyngeal resistance can lead to collapse of the airway and periodic partial or complete upper airway obstruction. Anatomical optical coherence tomography (OCT) has the potential to provide high-speed three-dimensional tomographic images of the airway lumen without the use of ionizing radiation. In this chapter we describe the methods behind endoscopic OCT imaging and processing to generate full three dimensional anatomical models of the human airway which can be used in conjunction with numerical simulation methods to assess areas of airway obstruction. Combining this structural information with flow dynamic simulations, we can better estimate the site and causes of airway obstruction and better select and design surgery for patients with obstructive sleep apnea.

  5. The influence of nutrition on the insulin-like growth factor system and the concentrations of growth hormone, glucose, insulin, gonadotropins and progesterone in ovarian follicular fluid and plasma from adult female horses (Equus caballus)

    PubMed Central

    2014-01-01

    Background Feed intake affects the GH-IGF system and may be a key factor in determining the ovarian follicular growth rate. In fat mares, the plasma IGF-1 concentration is high with low GH and a quick follicular growth rate, in contrast to values observed in thin mares. Nothing is known regarding the long-term effects of differential feed intake on the IGF system. The objective of this experiment was to quantify IGFs, IGFBPs, GH, glucose, insulin, gonadotropin and progesterone (P4) in blood and in preovulatory follicular fluid (FF) in relation to feeding levels in mares. Methods Three years prior to the experiment, Welsh Pony mares were assigned to a restricted diet group (R, n = 10) or a well-fed group (WF, n = 9). All mares were in good health and exhibited differences in body weight and subcutaneous fat thickness. Follicular development was scanned daily and plasma was also collected daily. Preovulatory FF was collected by ultrasound-guided follicular aspiration. Hormone levels were assayed in FF and plasma with a validated RIA. Results According to scans, the total number of follicles in group R was 53% lower than group WF. Insulin and IGF-1 concentrations were higher in WF than in R mares. GH and IGF-2 concentrations were lower in plasma from WF mares than from R mares, but the difference was not significant in FF. The IGFBP-2/IGFBP-3 ratio in FF was not affected by feeding but was dramatically increased in R mare plasma. No difference in gonadotropin concentration was found with the exception of FSH, which was higher in the plasma of R mares. On the day of puncture, P4 concentrations were not affected by feeding but were higher in preovulatory FF than in plasma. Conclusions The bioavailability of IGF-1 or IGF-2, represented by the IGFBP2/IGFBP3 ratio, is modified by feed intake in plasma but not in FF. These differences partially explain the variability in follicular growth observed between well-fed mares and mares on restricted diets. PMID:25078409

  6. Ion channel regulation of intracellular calcium and airway smooth muscle function.

    PubMed

    Perez-Zoghbi, Jose F; Karner, Charlotta; Ito, Satoru; Shepherd, Malcolm; Alrashdan, Yazan; Sanderson, Michael J

    2009-10-01

    Airway hyper-responsiveness associated with asthma is mediated by airway smooth muscle cells (SMCs) and has a complicated etiology involving increases in cell contraction and proliferation and the secretion of inflammatory mediators. Although these pathological changes are diverse, a common feature associated with their regulation is a change in intracellular Ca(2+) concentration ([Ca(2+)](i)). Because the [Ca(2+)](i) itself is a function of the activity and expression of a variety of ion channels, in both the plasma membrane and sarcoplasmic reticulum of the SMC, the modification of this ion channel activity may predispose airway SMCs to hyper-responsiveness. Our objective is to review how ion channels determine the [Ca(2+)](i) and influence the function of airway SMCs and emphasize the potential of ion channels as sites for therapeutic approaches to asthma.

  7. Use of mucolytics to enhance magnetic particle retention at a model airway surface

    NASA Astrophysics Data System (ADS)

    Ally, Javed; Roa, Wilson; Amirfazli, A.

    A previous study has shown that retention of magnetic particles at a model airway surface requires prohibitively strong magnetic fields. As mucus viscoelasticity is the most significant factor contributing to clearance of magnetic particles from the airway surface, mucolytics are considered in this study to reduce mucus viscoelasticity and enable particle retention with moderate strength magnetic fields. The excised frog palate model was used to simulate the airway surface. Two mucolytics, N-acetylcysteine (NAC) and dextran sulfate (DS) were tested. NAC was found to enable retention at moderate field values (148 mT with a gradient of 10.2 T/m), whereas DS was found to be effective only for sufficiently large particle concentrations at the airway surface. The possible mechanisms for the observed behavior with different mucolytics are also discussed based on aggregate formation and the loading of cilia.

  8. The effect of short-term dietary supplementation with glucose on gastric emptying of glucose and fructose and oral glucose tolerance in normal subjects.

    PubMed

    Horowitz, M; Cunningham, K M; Wishart, J M; Jones, K L; Read, N W

    1996-04-01

    Recent observations indicate that gastric emptying may be influenced by patterns of previous nutrient intake. The aims of this study were to determine the effects of a high glucose diet on gastric emptying of glucose and fructose, and the impact of any changes in gastric emptying on plasma concentrations of glucose, insulin and gastric inhibitory polypeptide in response to glucose and fructose loads. Gastric emptying of glucose and fructose (both 75 g dissolved in 350 ml water) were measured in seven normal volunteers on separate days while each was on a "standard' diet and an identical diet supplemented with 440 g/day of glucose for 4-7 days. Venous blood samples for measurement of plasma glucose, insulin and gastric inhibitory polypeptide levels were taken immediately before and for 180 min after ingestion of glucose and fructose loads. Dietary glucose supplementation accelerated gastric emptying of glucose (50% emptying time 82 +/- 8 vs 106 +/- 10 min, p = 0.004) and fructose (73 +/- 9 vs 106 +/- 9 min, p = 0.001). After ingestion of glucose, plasma concentrations of insulin (p < 0.05) and gastric inhibitory polypeptide (p < 0.05) were higher during the glucose-supplemented diet. In contrast, plasma glucose concentrations at 60 min and 75 min were lower (p < 0.05) on the glucose-supplemented diet. We conclude that short-term supplementation of the diet with glucose accelerates gastric emptying of glucose and fructose, presumably as a result of reduced feedback inhibition of gastric emptying from small intestinal luminal receptors. More rapid gastric emptying of glucose has a significant impact on glucose tolerance.

  9. CSF glucose test

    MedlinePlus

    Glucose test - CSF; Cerebrospinal fluid glucose test ... The glucose level in the CSF should be 50 to 80 mg/100 mL (or greater than 2/3 ... Abnormal results include higher and lower glucose levels. Abnormal ... or fungus) Inflammation of the central nervous system Tumor

  10. Blood Test: Glucose

    MedlinePlus

    ... Your 1- to 2-Year-Old Blood Test: Glucose KidsHealth > For Parents > Blood Test: Glucose A A A What's in this article? What ... de sangre: glucosa What It Is A blood glucose test measures the amount of glucose (the main ...

  11. Arginase inhibition in airways from normal and nitric oxide synthase 2-knockout mice exposed to ovalbumin

    SciTech Connect

    Bratt, Jennifer M.; Franzi, Lisa M.; Linderholm, Angela L.; O'Roark, Erin M.; Kenyon, Nicholas J.; Last, Jerold A.

    2010-01-01

    Arginase1 and nitric oxide synthase2 (NOS2) utilize L-arginine as a substrate, with both enzymes expressed at high levels in the asthmatic lung. Inhibition of arginase in ovalbumin-exposed C57BL/6 mice with the transition state inhibitor N{sup o}mega-hydroxy-nor-L-arginine (nor-NOHA) significantly increased total L-arginine content in the airway compartment. We hypothesized that such an increase in L-arginine content would increase the amount of nitric oxide (NO) being produced in the airways and thereby decrease airway hyperreactivity and eosinophilic influx. We further hypothesized that despite arginase inhibition, NOS2 knockout (NOS2-/-) mice would be unable to up-regulate NO production in response to allergen exposure and would demonstrate higher amounts of airway hyperreactivity and eosinophilia under conditions of arginase inhibition than C57BL/6 animals. We found that administration of nor-NOHA significantly decreased airway hyperreactivity and eosinophilic airway inflammation in ovalbumin-exposed C57BL/6 mice, but these parameters were unchanged in ovalbumin-exposed NOS2-/- mice. Arginase1 protein content was increased in mice exposed to ovalbumin, an effect that was reversed upon nor-NOHA treatment in C57BL/6 mice. Arginase1 protein content in the airway compartment directly correlated with the degree of airway hyperreactivity in all treatment groups. NOS2-/- mice had significantly greater arginase1 and arginase2 concentrations compared to their respective C57BL/6 groups, indicating that inhibition of arginase may be dependent upon NOS2 expression. Arginase1 and 2 content were not affected by nor-NOHA administration in the NOS2-/- mice. We conclude that L-arginine metabolism plays an important role in the development of airway hyperreactivity and eosinophilic airway inflammation. Inhibition of arginase early in the allergic inflammatory response decreases the severity of the chronic inflammatory phenotype. These effects appear to be attributable to NOS2

  12. Role of Matrix Metalloproteinases-1 and -2 in Interleukin-13–Suppressed Elastin in Airway Fibroblasts in Asthma

    PubMed Central

    Slade, David; Church, Tony D.; Francisco, Dave; Heck, Karissa; Sigmon, R. Wesley; Ghio, Michael; Murillo, Anays; Firszt, Rafael; Lugogo, Njira L.; Que, Loretta; Sunday, Mary E.; Kraft, Monica

    2016-01-01

    Elastin synthesis and degradation in the airway and lung parenchyma contribute to airway mechanics, including airway patency and elastic recoil. IL-13 mediates many features of asthma pathobiology, including airway remodeling, but the effects of IL-13 on elastin architecture in the airway wall are not known. We hypothesized that IL-13 modulates elastin expression in airway fibroblasts from subjects with allergic asthma. Twenty-five subjects with mild asthma (FEV1, 89 ± 3% predicted) and 30 normal control subjects (FEV1, 102 ± 2% predicted) underwent bronchoscopy with endobronchial biopsy. Elastic fibers were visualized in airway biopsy specimens using Weigert’s resorcin-fuchsin elastic stain. Airway fibroblasts were exposed to IL-13; a pan-matrix metalloproteinase (MMP) inhibitor (GM6001); specific inhibitors to MMP-1, -2, -3, and -8; and combinations of IL-13 with MMP inhibitors in separate conditions in serum-free media for 48 hours. Elastin (ELN) expression as well as MMP secretion and activity were quantified. Results of this study show that elastic fiber staining of airway biopsy tissue was significantly associated with methacholine PC20 (i.e., the provocative concentration of methacholine resulting in a 20% fall in FEV1 levels) in patients with asthma. IL-13 significantly suppressed ELN expression in asthmatic airway fibroblasts as compared with normal control fibroblasts. The effect of IL-13 on ELN expression was significantly correlated with postbronchodilator FEV1/FVC in patients with asthma. MMP inhibition significantly stimulated ELN expression in patients with asthma as compared with normal control subjects. Specific inhibition of MMP-1 and MMP-2, but not MMP-3 or MMP-8, reversed the IL-13–induced suppression of ELN expression. In asthma, MMP-1 and MMP-2 mediate IL-13–induced suppression of ELN expression in airway fibroblasts. PMID:26074138

  13. Glucose-dependent insulinotropic polypeptide directly induces glucose transport in rat skeletal muscle.

    PubMed

    Snook, Laelie A; Nelson, Emery M; Dyck, David J; Wright, David C; Holloway, Graham P

    2015-08-01

    Several gastrointestinal proteins have been identified to have insulinotropic effects, including glucose-dependent insulinotropic polypeptide (GIP); however, the direct effects of incretins on skeletal muscle glucose transport remain largely unknown. Therefore, the purpose of the current study was to examine the role of GIP on skeletal muscle glucose transport and insulin signaling in rats. Relative to a glucose challenge, a mixed glucose+lipid oral challenge increased circulating GIP concentrations, skeletal muscle Akt phosphorylation, and improved glucose clearance by ∼35% (P < 0.05). These responses occurred without alterations in serum insulin concentrations. In an incubated soleus muscle preparation, GIP directly stimulated glucose transport and increased GLUT4 accumulation on the plasma membrane in the absence of insulin. Moreover, the ability of GIP to stimulate glucose transport was mitigated by the addition of the PI 3-kinase (PI3K) inhibitor wortmannin, suggesting that signaling through PI3K is required for these responses. We also provide evidence that the combined stimulatory effects of GIP and insulin on soleus muscle glucose transport are additive. However, the specific GIP receptor antagonist (Pro(3))GIP did not attenuate GIP-stimulated glucose transport, suggesting that GIP is not signaling through its classical receptor. Together, the current data provide evidence that GIP regulates skeletal muscle glucose transport; however, the exact signaling mechanism(s) remain unknown.

  14. Glucose sensing mechanisms in hypothalamic cell models: glucose inhibition of AgRP synthesis and secretion.

    PubMed

    Chalmers, Jennifer A; Jang, Janet J; Belsham, Denise D

    2014-01-25

    Glucose-sensing neurons play a role in energy homeostasis, yet how orexigenic neurons sense glucose remains unclear. As models of glucose-inhibited (GI) neurons, mHypoE-29/1 and mHypoA-NPY/GFP cells express the essential orexigenic neuropeptide AgRP and glucose sensing machinery. Exposure to increasing concentrations of glucose or the glucose analog 2-deoxyglucose (2-DG) results in a decrease in AgRP mRNA levels. Taste receptor, Tas1R2 mRNA expression was reduced by glucose, whereas 2-DG reduced Tas1R3 mRNA levels. Increasing glucose concentrations elicited a rise in Akt and neuronal nitric oxide synthase (nNOS) phosphorylation, CaMKKβ levels, and a reduction of AMP-kinase alpha phosphorylation. Inhibitors of NOS and the cystic fibrosis transmembrane conductance regulator (CFTR) prevented a decrease in AgRP secretion with glucose, suggesting a pivotal role for nNOS and the CFTR in glucose-sensing. These models possess the hallmark characteristics of GI neurons, and can be used to disentangle the mechanisms by which orexigenic neurons sense glucose.

  15. Brain areas and pathways in the regulation of glucose metabolism.

    PubMed

    Diepenbroek, Charlene; Serlie, Mireille J; Fliers, Eric; Kalsbeek, Andries; la Fleur, Susanne E

    2013-01-01

    Glucose is the most important source of fuel for the brain and its concentration must be kept within strict boundaries to ensure the organism's optimal fitness. To maintain glucose homeostasis, an optimal balance between glucose uptake and glucose output is required. Besides managing acute changes in plasma glucose concentrations, the brain controls a daily rhythm in glucose concentrations. The various nuclei within the hypothalamus that are involved in the control of both these processes are well known. However, novel studies indicate an additional role for brain areas that are originally appreciated in other processes than glucose metabolism. Therefore, besides the classic hypothalamic pathways, we will review cortico-limbic brain areas and their role in glucose metabolism.

  16. Continuous glucose monitoring, oral glucose tolerance, and insulin - glucose parameters in adolescents with simple obesity.

    PubMed

    El Awwa, A; Soliman, A; Al-Ali, M; Yassin, M; De Sanctis, V

    2012-09-01

    In obese adolescents pancreatic beta-cells may not be able to cope with insulin resistance leading to hyperglycemia and type2 diabetes (T2DM To assess oral glucose tolerance, 72-h continuous blood glucose concentrations (CGM) and calculate homeostatic model assessment (HOMA), and the quantitative insulin sensitivity check index (QUICKI) in 13 adolescents with simple obesity (BMI SDS=4 ± 1.06). OGTT performed in 13 obese adolescents (13.47 ± 3 years) revealed 3 cases (23%) with impaired fasting glucose (IFG: fasting glucose >5.6 mmol/L), 4 cases (30%) with impaired glucose tolerance (IGT: 2h blood glucose >7.8 <11.1 mmol/L), and none with diabetes. Using the continuous glucose monitoring system ( CGMS), IFG was detected in 4 cases, the maximum serum blood glucose (BG : 2h or more after meal) was >7.8 and <11.1 mmol/L (IGT) in 9 children (69%) and >11.1 mmol/L (diabetes) in one case (7.6%). Five cases had a minimum BG recorded of <2.7 mmol/L (hypoglycemia). No glycemic abnormality was detected using HbA1C (5.7 ± 0.3%). 11/13 patients had HOMA values >2.6 and QUICKI values <0.35 denoting insulin resistance. Beta cell mass percent (B %) = 200 ± 94.8% and insulin sensitivity values (IS)=50.4 ± 45.5% denoted insulin resistance with hyper-insulinaemia and preserved beta cell mass. In obese adolescents, CGMS is superior to OGTT and HbA1C in detecting glycemic abnormalities, which appears to be secondary to insulin resistance.

  17. Computational fluid dynamics modeling of Bacillus anthracis spore deposition in rabbit and human respiratory airways

    SciTech Connect

    Kabilan, S.; Suffield, S. R.; Recknagle, K. P.; Jacob, R. E.; Einstein, D. R.; Kuprat, A. P.; Carson, J. P.; Colby, S. M.; Saunders, J. H.; Hines, S. A.; Teeguarden, J. G.; Straub, T. M.; Moe, M.; Taft, S. C.; Corley, R. A.

    2016-09-01

    Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived respectively from computed tomography (CT) and µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation–exhalation breathing conditions using average species-specific minute volumes. Two different exposure scenarios were modeled in the rabbit based upon experimental inhalation studies. For comparison, human simulations were conducted at the highest exposure concentration used during the rabbit experimental exposures. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the nasal sinus compared to the human at the same air concentration of anthrax spores. In contrast, higher spore deposition was predicted in the lower conducting airways of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology for deposition.

  18. Inhaled Bordetella pertussis vaccine decreases airway responsiveness in guinea pigs.

    PubMed

    Vargas, M H; Bazán-Perkins, B; Segura, P; Campos, M G; Selman, M; Montaño, L M

    1995-01-01

    Bordetella pertussis (BP) has been used as adjuvant for experimental animal immunization, but its effects on airway responsiveness are uncertain. Three groups of guinea pigs were used: animals with a single exposure to inhaled BP vaccine (strain 134, total dose 1.24 x 10(12) germs), animals submitted to a sensitization procedure through inhalation of ovalbumin plus BP, and healthy control animals. Four weeks after inhalation of BP or after the beginning of sensitization, dose- or concentration-response curves to histamine were constructed in vivo and in vitro (tracheal and parenchymal preparations). We found that BP alone produced lower responses to histamine than control guinea pigs in vivo (insufflation pressure, p = 0.0003) and in tracheal tissues (p = 0.04), but not in parenchymal preparations. Sensitization did not modify the responsiveness compared with their respective controls. These results suggest that some BP component(s), probably pertussis toxin, causes a long lasting airway hyporesponsiveness in guinea pigs.

  19. Airway management: induced tension pneumoperitoneum

    PubMed Central

    Ahmed, Khedher; Amine, El Ghali Mohamed; Abdelbaki, Azouzi; Jihene, Ayachi; Khaoula, Meddeb; Yamina, Hamdaoui; Mohamed, Boussarsar

    2016-01-01

    Pneumoperitoneum is not always associated with hollow viscus perforation. Such condition is called non-surgical or spontaneous pneumoperitoneum. Intrathoracic causes remain the most frequently reported mechanism inducing this potentially life threatening complication. This clinical condition is associated with therapeutic dilemma. We report a case of a massive isolated pneumoperitoneum causing acute abdominal hypertension syndrome, in a 75 year female, which occurred after difficult airway management and mechanical ventilation. Emergent laparotomy yielded to full recovery. The recognition of such cases for whom surgical management can be avoided is primordial to avoid unnecessary laparotomy and its associated morbidity particularly in the critically ill.

  20. Airway smooth muscle dynamics: a common pathway of airway obstruction in asthma.

    PubMed

    An, S S; Bai, T R; Bates, J H T; Black, J L; Brown, R H; Brusasco, V; Chitano, P; Deng, L; Dowell, M; Eidelman, D H; Fabry, B; Fairbank, N J; Ford, L E; Fredberg, J J; Gerthoffer, W T; Gilbert, S H; Gosens, R; Gunst, S J; Halayko, A J; Ingram, R H; Irvin, C G; James, A L; Janssen, L J; King, G G; Knight, D A; Lauzon, A M; Lakser, O J; Ludwig, M S; Lutchen, K R; Maksym, G N; Martin, J G; Mauad, T; McParland, B E; Mijailovich, S M; Mitchell, H W; Mitchell, R W; Mitzner, W; Murphy, T M; Paré, P D; Pellegrino, R; Sanderson, M J; Schellenberg, R R; Seow, C Y; Silveira, P S P; Smith, P G; Solway, J; Stephens, N L; Sterk, P J; Stewart, A G; Tang, D D; Tepper, R S; Tran, T; Wang, L

    2007-05-01

    Excessive airway obstruction is the cause of symptoms and abnormal lung function in asthma. As airway smooth muscle (ASM) is the effecter controlling airway calibre, it is suspected that dysfunction of ASM contributes to the pathophysiology of asthma. However, the precise role of ASM in the series of events leading to asthmatic symptoms is not clear. It is not certain whether, in asthma, there is a change in the intrinsic properties of ASM, a change in the structure and mechanical properties of the noncontractile components of the airway wall, or a change in the interdependence of the airway wall with the surrounding lung parenchyma. All these potential changes could result from acute or chronic airway inflammation and associated tissue repair and remodelling. Anti-inflammatory therapy, however, does not "cure" asthma, and airway hyperresponsiveness can persist in asthmatics, even in the absence of airway inflammation. This is perhaps because the therapy does not directly address a fundamental abnormality of asthma, that of exaggerated airway narrowing due to excessive shortening of ASM. In the present study, a central role for airway smooth muscle in the pathogenesis of airway hyperresponsiveness in asthma is explored.

  1. Glucose metabolism in rat retinal pigment epithelium.

    PubMed

    Coffe, Víctor; Carbajal, Raymundo C; Salceda, Rocío

    2006-01-01

    The retinal pigment epithelium (RPE) is the major transport pathway for exchange of metabolites and ions between choroidal blood supply and the neural retina. To gain insight into the mechanisms controlling glucose metabolism in RPE and its possible relationship to retinopathy, we studied the influence of different glucose concentrations on glycogen and lactate levels and CO(2) production in RPE from normal and streptozotocin-treated diabetic rats. Incubation of normal RPE in the absence of glucose caused a decrease in lactate production and glycogen content. In normal RPE, increasing glucose concentrations from 5.6 mM to 30 mM caused a four-fold increase in glucose accumulation and CO(2) yield, as well as reduction in lactate and glycogen production. In RPE from diabetic rats glucose accumulation did not increase in the presence of high glucose substrate, but it showed a four- and a seven-fold increase in CO(2) production through the mitochondrial and pentose phosphate pathways, respectively. We found high glycogen levels in RPE which can be used as an energy reserve for RPE itself and/or neural retina. Findings further show that the RPE possesses a high oxidative capacity. The large increase in glucose shunting to the pentose phosphate pathway in diabetic retina exposed to high glucose suggests a need for reducing capacity, consistent with increased oxidative stress.

  2. Mechanisms of inflammation-mediated airway smooth muscle plasticity and airways remodeling in asthma.

    PubMed

    Halayko, Andrew J; Amrani, Yassine

    2003-09-16

    Recent evidence points to progressive structural change in the airway wall, driven by chronic local inflammation, as a fundamental component for development of irreversible airway hyperresponsiveness. Acute and chronic inflammation is orchestrated by cytokines from recruited inflammatory cells, airway myofibroblasts and myocytes. Airway myocytes exhibit functional plasticity in their capacity for contraction, proliferation, and synthesis of matrix protein and cytokines. This confers a principal role in driving different components of the airway remodeling process, and mediating constrictor hyperresponsiveness. Functional plasticity of airway smooth muscle (ASM) is regulated by an array of environmental cues, including cytokines, which mediate their effects through receptors and a number of intracellular signaling pathways. Despite numerous studies of the cellular effects of cytokines on cultured airway myocytes, few have identified how intracellular signaling pathways modulate or induce these cellular responses. This review summarizes current understanding of these concepts and presents a model for the effects of inflammatory mediators on functional plasticity of ASM in asthma.

  3. 21 CFR 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oropharyngeal airway. 868.5110 Section 868.5110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5110 Oropharyngeal airway....

  4. 21 CFR 868.5100 - Nasopharyngeal airway.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nasopharyngeal airway. 868.5100 Section 868.5100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5100 Nasopharyngeal airway....

  5. SUBCHRONIC ENDOTOXIN INHALATION CAUSES PERSISTENT AIRWAY DISEASE

    EPA Science Inventory

    ABSTRACT

    The endotoxin component of organic dusts causes acute reversible airflow obstruction and airway inflammation. To test the hypothesis that endotoxin alone causes airway remodeling, we have compared the response of two inbred mouse strains to subchronic endotoxin ...

  6. Upper airway resistance: species-related differences.

    PubMed

    Kirschvink, N; Reinhold, P

    2010-07-01

    In veterinary medicine, upper airway resistance deserves a particular attention in equines athletes and brachycephalic dogs. Due to the anatomical peculiarities of the upper airway and/or pathological conditions, significant alterations of performance and/or well being might occur in horses and dogs. Physiological specificities and pathological changes of the lower respiratory tract deserve a major attention in other species.

  7. Airway and Extracellular Matrix Mechanics in COPD

    PubMed Central

    Bidan, Cécile M.; Veldsink, Annemiek C.; Meurs, Herman; Gosens, Reinoud

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases worldwide, and is characterized by airflow obstruction that is not fully reversible with treatment. Even though airflow obstruction is caused by airway smooth muscle contraction, the extent of airway narrowing depends on a range of other structural and functional determinants that impact on active and passive tissue mechanics. Cells and extracellular matrix in the airway and parenchymal compartments respond both passively and actively to the mechanical stimulation induced by smooth muscle contraction. In this review, we summarize the factors that regulate airway narrowing and provide insight into the relative contributions of different constituents of the extracellular matrix and their biomechanical impact on airway obstruction. We then review the changes in extracellular matrix composition in the airway and parenchymal compartments at different stages of COPD, and finally discuss how these changes impact airway narrowing and the development of airway hyperresponsiveness. Finally, we position these data in the context of therapeutic research focused on defective tissue repair. As a conclusion, we propose that future works should primarily target mild or early COPD, prior to the widespread structural changes in the alveolar compartment that are more characteristic of severe COPD. PMID:26696894

  8. Difficult Airway Response Team: A Novel Quality Improvement Program for Managing Hospital-Wide Airway Emergencies

    PubMed Central

    Mark, Lynette J.; Herzer, Kurt R.; Cover, Renee; Pandian, Vinciya; Bhatti, Nasir I.; Berkow, Lauren C.; Haut, Elliott R.; Hillel, Alexander T.; Miller, Christina R.; Feller-Kopman, David J.; Schiavi, Adam J.; Xie, Yanjun J.; Lim, Christine; Holzmueller, Christine; Ahmad, Mueen; Thomas, Pradeep; Flint, Paul W.; Mirski, Marek A.

    2015-01-01

    Background Difficult airway cases can quickly become emergencies, increasing the risk of life-threatening complications or death. Emergency airway management outside the operating room is particularly challenging. Methods We developed a quality improvement program—the Difficult Airway Response Team (DART)—to improve emergency airway management outside the operating room. DART was implemented by a team of anesthesiologists, otolaryngologists, trauma surgeons, emergency medicine physicians, and risk managers in 2005 at The Johns Hopkins Hospital in Baltimore, Maryland. The DART program had three core components: operations, safety, and education. The operations component focused on developing a multidisciplinary difficult airway response team, standardizing the emergency response process, and deploying difficult airway equipment carts throughout the hospital. The safety component focused on real-time monitoring of DART activations and learning from past DART events to continuously improve system-level performance. This objective entailed monitoring the paging system, reporting difficult airway events and DART activations to a web-based registry, and using in situ simulations to identify and mitigate defects in the emergency airway management process. The educational component included development of a multispecialty difficult airway curriculum encompassing case-based lectures, simulation, and team building/communication to ensure consistency of care. Educational materials were also developed for non-DART staff and patients to inform them about the needs of patients with difficult airways and ensure continuity of care with other providers after discharge. Results Between July 2008 and June 2013, DART managed 360 adult difficult airway events comprising 8% of all code activations. Predisposing patient factors included body mass index > 40, history of head and neck tumor, prior difficult intubation, cervical spine injury, airway edema, airway bleeding, and previous

  9. The critical airway in adults: The facts

    PubMed Central

    Bonanno, Fabrizio Giuseppe

    2012-01-01

    An algorithm on the indications and timing for a surgical airway in emergency as such cannot be drawn due to the multiplicity of variables and the inapplicability in the context of life-threatening critical emergency, where human brain elaborates decisions better in cluster rather than in binary fashion. In particular, in emergency or urgent scenarios, there is no clear or established consensus as to specifically who should receive a tracheostomy as a life-saving procedure; and more importantly, when. The two classical indications for emergency tracheostomy (laryngeal injury and failure to secure airway with endotracheal intubation or cricothyroidotomy) are too generic and encompass a broad spectrum of possibilities. In literature, specific indications for emergency tracheostomy are scattered and are biased, partially comprehensive, not clearly described or not homogeneously gathered. The review highlights the indications and timing for an emergency surgical airway and gives recommendations on which surgical airway method to use in critical airway. PMID:22787346

  10. A self-powered glucose biosensing system.

    PubMed

    Slaughter, Gymama; Kulkarni, Tanmay

    2016-04-15

    A self-powered glucose biosensor (SPGS) system is fabricated and in vitro characterization of the power generation and charging frequency characteristics in glucose analyte are described. The bioelectrodes consist of compressed network of three-dimensional multi-walled carbon nanotubes with redox enzymes, pyroquinoline quinone glucose dehydrogenase (PQQ-GDH) and laccase functioning as the anodic and cathodic catalyst, respectively. When operated in 45 mM glucose, the biofuel cell exhibited an open circuit voltage and power density of 681.8 mV and 67.86 µW/cm(2) at 335 mV, respectively, with a current density of 202.2 µA/cm(2). Moreover, at physiological glucose concentration (5mM), the biofuel cell exhibits open circuit voltage and power density of 302.1 mV and 15.98 µW/cm(2) at 166.3 mV, respectively, with a current density of 100 µA/cm(2). The biofuel cell assembly produced a linear dynamic range of 0.5-45 mM glucose. These findings show that glucose biofuel cells can be further investigated in the development of a self-powered glucose biosensor by using a capacitor as the transducer element. By monitoring the capacitor charging frequencies, which are influenced by the concentration of the glucose analyte, a linear dynamic range of 0.5-35 mM glucose is observed. The operational stability of SPGS is monitored over a period of 63 days and is found to be stable with 15.38% and 11.76% drop in power density under continuous discharge in 10mM and 20mM glucose, respectively. These results demonstrate that SPGSs can simultaneously generate bioelectricity to power ultra-low powered devices and sense glucose.

  11. Investigating the geometry of pig airways using computed tomography

    NASA Astrophysics Data System (ADS)

    Mansy, Hansen A.; Azad, Md Khurshidul; McMurray, Brandon; Henry, Brian; Royston, Thomas J.; Sandler, Richard H.

    2015-03-01

    Numerical modeling of sound propagation in the airways requires accurate knowledge of the airway geometry. These models are often validated using human and animal experiments. While many studies documented the geometric details of the human airways, information about the geometry of pig airways is scarcer. In addition, the morphology of animal airways can be significantly different from that of humans. The objective of this study is to measure the airway diameter, length and bifurcation angles in domestic pigs using computed tomography. After imaging the lungs of 3 pigs, segmentation software tools were used to extract the geometry of the airway lumen. The airway dimensions were then measured from the resulting 3 D models for the first 10 airway generations. Results showed that the size and morphology of the airways of different animals were similar. The measured airway dimensions were compared with those of the human airways. While the trachea diameter was found to be comparable to the adult human, the diameter, length and branching angles of other airways were noticeably different from that of humans. For example, pigs consistently had an early airway branching from the trachea that feeds the superior (top) right lung lobe proximal to the carina. This branch is absent in the human airways. These results suggested that the human geometry may not be a good approximation of the pig airways and may contribute to increasing the errors when the human airway geometric values are used in computational models of the pig chest.

  12. Intrathoracic airway measurement: ex-vivo validation

    NASA Astrophysics Data System (ADS)

    Reinhardt, Joseph M.; Raab, Stephen A.; D'Souza, Neil D.; Hoffman, Eric A.

    1997-05-01

    High-resolution x-ray CT (HRCT) provides detailed images of the lungs and bronchial tree. HRCT-based imaging and quantitation of peripheral bronchial airway geometry provides a valuable tool for assessing regional airway physiology. Such measurements have been sued to address physiological questions related to the mechanics of airway collapse in sleep apnea, the measurement of airway response to broncho-constriction agents, and to evaluate and track the progression of disease affecting the airways, such as asthma and cystic fibrosis. Significant attention has been paid to the measurements of extra- and intra-thoracic airways in 2D sections from volumetric x-ray CT. A variety of manual and semi-automatic techniques have been proposed for airway geometry measurement, including the use of standardized display window and level settings for caliper measurements, methods based on manual or semi-automatic border tracing, and more objective, quantitative approaches such as the use of the 'half-max' criteria. A recently proposed measurements technique uses a model-based deconvolution to estimate the location of the inner and outer airway walls. Validation using a plexiglass phantom indicates that the model-based method is more accurate than the half-max approach for thin-walled structures. In vivo validation of these airway measurement techniques is difficult because of the problems in identifying a reliable measurement 'gold standard.' In this paper we report on ex vivo validation of the half-max and model-based methods using an excised pig lung. The lung is sliced into thin sections of tissue and scanned using an electron beam CT scanner. Airways of interest are measured from the CT images, and also measured with using a microscope and micrometer to obtain a measurement gold standard. The result show no significant difference between the model-based measurements and the gold standard; while the half-max estimates exhibited a measurement bias and were significantly

  13. Specificity of noninvasive blood glucose monitoring with optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Larin, Kirill V.; Ashitkov, Taras V.; Motamedi, Massoud; Esenaliev, Rinat O.

    2003-07-01

    Management of diabetic disease requires frequent monitoring of blood glucose concentration. Development of a noninvasive technique capable of reliable and sensitive monitoring of blood glucose concentration would considerably improve quality of life of diabetic patients and reduce mortality associated with this disease. Recently, we proposed to use Optical Coherence Tomography (OCT) technique for noninvasive glucose monitoring. In this paper, we tested in animals several aspects of specificity of noninvasive blood glucose monitoring with the OCT technique. Influence of temperature and tissue heterogeneity on the OCT signal profile is experimentally studied in this paper. We also theoretically investigated the changes in tissue scattering induced by variation of concentration of glucose and other osmolytes. Obtained results suggest that although several physical and chemical agents could potentially interfere with blood glucose concentration measurements using the OCT technique, their effect is smaller compared to that of glucose under normal physiological conditions.

  14. [Continuous positive airways pressure treatment for obstructive sleep apnoea].

    PubMed

    Antone, E; Gilbert, M; Bironneau, V; Meurice, J C

    2015-04-01

    Continuous positive airway pressure (CPAP) still remains the most frequently used and the most efficient treatment for obstructive sleep apnea syndrome. However, its efficiency is conditioned by healthcare quality depending on many factors such as medical specificities of the patients as well as the severity of sleep-related breathing disorders. In order to optimize CPAP efficiency, it is necessary to be aware of the functional abilities of the different devices, and to perform a close monitoring of the patients, particularly during the first weeks of treatment, by maximally using the data provided by the CPAP apparatus. Some questions remain unsolved, such as the impact of nasal CPAP on glucose metabolism or cardiovascular prognosis. Furthermore, the strategy of CPAP use should be improved according to future results of studies dedicated to the interest of home telemonitoring and taking into account the validated mode of CPAP initiation.

  15. Computational modeling of unsteady surfactant-laden liquid plug propagation in neonatal airways

    NASA Astrophysics Data System (ADS)

    Olgac, Ufuk; Muradoglu, Metin

    2013-07-01

    Surfactant-free and surfactant-laden liquid plug propagation in neonatal airways in various generations representing the upper and lower airways are investigated computationally using a finite-difference/front-tracking method. Emphasis is placed on the unsteady surfactant-laden plug propagation as a model for Surfactant Replacement Therapy (SRT) and airway reopening. The numerical method is designed to solve the evolution equations of the interfacial and bulk surfactant concentrations coupled with the incompressible Navier-Stokes equations. Available experimental data for surfactant Survanta are used to relate surface tension coefficient to surfactant concentration at the interface. It is found that, for the surfactant-free case, the trailing film thickness is in good agreement with Taylor's law for plugs with plug length greater than the airway width. Mechanical stresses that could be injurious to epithelial cells such as pressure and shear stress and their gradients are maximized on the front and rear menisci with increasing magnitudes in the lower generations. These mechanical stresses, especially pressure and pressure gradient, are diminished with the introduction of surfactants. Surfactant is absorbed onto the trailing film and thickens it, eventually leading to either plug rupture or, if totally consumed prior to rupture, to steadily propagating plug. In the upper airways, initially small plugs rupture rapidly and plugs with comparable initial plug length with the airway width persist and propagate steadily. For a more effective SRT treatment, we recommend utilization of plugs with initial plug length greater than the airway width. Increasing surfactant strength or increasing the initially instilled surfactant concentration is found to be ineffective.

  16. The Effects of Proresolution of Ellagic Acid in an Experimental Model of Allergic Airway Inflammation

    PubMed Central

    de Freitas Alves, Claudiney; Angeli, Giovanna Natalia; Favarin, Daniely Cornélio; Lemos de Andrade, Edinéia; Lazo Chica, Javier Emilio; Faccioli, Lúcia Helena; Roberto da Silva, Paulo; de Paula Rogerio, Alexandre

    2013-01-01

    Asthma is a disease of airway inflammation characterized by airway hyperresponsiveness, eosinophilic inflammation, and hypersecretion of mucus. Ellagic acid, a compound derived from medicinal plants and fruits, has shown anti-inflammatory activity in several experimental disease models. We used the classical experimental model, in BALB/c mice, of sensibilization with ovalbumin to determine the effect of ellagic acid (10 mg/kg; oral route) in the resolution of allergic airways response. Dexamethasone (1 mg/kg; subcutaneous route) was used as a positive control. The control group consisted of nonimmunized mice that received challenge with ovalbumin. Ellagic acid and dexamethasone or vehicle (water) were administered before or after intranasal allergen challenge. Ellagic acid accelerated the resolution of airways inflammation by decreasing total leukocytes and eosinophils numbers in the bronchoalveolar lavage fluid (BALF), the mucus production and lung inflammation in part by reducing IL-5 concentration, eosinophil peroxidase (EPO) activity, and P-selectin expression, but not activator protein 1 (AP-1) and nuclear factor kappa B (NF-κB) pathways. In addition, ellagic acid enhanced alveolar macrophage phagocytosis of IgG-OVA-coated beads ex vivo, a new proresolving mechanism for the clearance of allergen from the airways. Together, these findings identify ellagic acid as a potential therapeutic agent for accelerating the resolution of allergic airways inflammation. PMID:24376308

  17. An analysis of pollutant gas transport and absorption in pulmonary airways

    SciTech Connect

    Grotberg, J.B.; Sheth, B.V.; Mockros, L.F. )

    1990-05-01

    A mathematical model of ozone absorption, or for any soluble gas that has similar transport properties, is developed for a branching network of liquid-lined cylinders. In particular, we investigate specific flow regimes for finite length tubes where boundary layer phenomena and entrance effects exist in high Reynolds and Peclet (Pe) number airways. The smaller airways which have lower Reynolds and Peclet number flows are modelled by incorporating the detailed analysis found in (10) and modifying it for airways which have alveolated surfaces. We also consider a reacting gas and treat specific regimes where the reaction front is located at the air-liquid interface, within the liquid or at the liquid-tissue interface. Asymptotic methods are used in regions of the tracheobronchial tree where Pe much less than 1 and Pe much greater than 1. In addition, the fact that the radial transport parameter gamma much less than 1 for this toxin, and others such as nitrous oxides, is employed to simplify the analysis. The ozone concentrations, airway absorption and tissue dose are examined as a function of airway generation for several values of the governing parameters. The general result is a maximal dosing in airway generations 17 to 18 that is much larger (up to an order of magnitude) than the predictions of previous theories.

  18. Involvement of superoxide in ozone-induced airway hyperresponsiveness in anesthetized cats

    SciTech Connect

    Takahashi, T.; Miura, M.; Katsumata, U.; Ichinose, M.; Kimura, K.; Inoue, H.; Takishima, T.; Shirato, K. )

    1993-07-01

    To determine whether oxygen radical scavengers inhibit ozone-induced airway hyperresponsiveness, we examined the protective effect of polyethylene glycol-superoxide dismutase (PEG-SOD) and PEG-catalase (PEG-CAT) on ozone-induced airway hyperresponsiveness in cat airways. Twenty-five cats divided into five groups were anesthetized and mechanically ventilated. There was no difference between the groups in baseline airway responsiveness to inhaled acetylcholine (ACh). In the control group, AChPC, the concentration required to produce a doubling increase in baseline pulmonary resistance, was significantly reduced by ozone exposure (2.0 ppm for 2 h); the ratios of AChPC before ozone exposure to after ozone exposure (AChPC ratio) were 14.8 +/- 5.7 (p < 0.001) and 4.80 +/- 1.6 (p < 0.01) 30 and 120 min after exposure, respectively. Local administration of PEG-SOD (2,000 U/kg) into airways partially but significantly prevented ozone-induced airway hyperresponsiveness. The AChPC ratios were 6.2 +/- 1.4 and 1.5 +/- 0.2 30 and 120 min after exposure, respectively, which were significantly different from those of the control group (p < 0.05), whereas PEG-CAT pretreatment (6,000 U/kg) was without effect. Combined pretreatment with PEG-SOD and PEG-CAT had no additional protective effect compared with PEG-SOD alone. PEG-SOD had no direct effect on airway responsiveness to ACh. These results suggest that superoxide may be involved in ozone-induced airway hyperresponsiveness.

  19. Respiratory symptoms and airway responsiveness in apparently healthy workers exposed to flour dust.

    PubMed

    Bohadana, A B; Massin, N; Wild, P; Kolopp, M N; Toamain, J P

    1994-06-01

    Our aim was to measure the levels of exposure to wheat flour dust in a modern industrial bakery, and to assess the relationship between respiratory symptoms, sensitization to wheat flour antigens and airway responsiveness in the workforce. Forty four flour-exposed male workers and 164 unexposed controls were examined. Inspirable dust concentrations were measured using personal samplers. Respiratory symptoms were assessed by questionnaire, sensitization to wheat flour antigens by skin-prick tests, and methacholine airway challenge (MAC) test using an abbreviated method. Subjects were labelled MAC+ if forced expiratory volume in one second (FEV1) fell by 20% or more. The linear dose-response slope (DRS) was calculated as the percentage fall in FEV1 at last dose divided by the total dose administered. Inspirable dust concentrations were within acceptable limits in all working areas but one. The proportion of subjects with one or more symptoms and with airway hyperresponsiveness was significantly greater among flour-exposed workers than among controls. Using logistic or linear regression analysis, airway responsiveness was found to be strongly related to working at the bakery and to the baseline level of lung function. A positive skin-prick test was found in only 11% of flour-exposed workers and 6% of controls. In conclusion, our data show that despite exposure to relatively low concentration levels of inspirable flour dust, subjects working in the baking industry are at risk of developing both respiratory symptoms and airway hyperresponsiveness.

  20. Fetal programming of perivenous glucose uptake reveals a regulatory mechanism governing hepatic glucose output during refeeding.

    PubMed

    Murphy, Helena C; Regan, Gemma; Bogdarina, Irina G; Clark, Adrian J L; Iles, Richard A; Cohen, Robert D; Hitman, Graham A; Berry, Colin L; Coade, Zoe; Petry, Clive J; Burns, Shamus P

    2003-06-01

    Increased hepatic gluconeogenesis maintains glycemia during fasting and has been considered responsible for elevated hepatic glucose output in type 2 diabetes. Glucose derived periportally via gluconeogenesis is partially taken up perivenously in perfused liver but not in adult rats whose mothers were protein-restricted during gestation (MLP rats)-an environmental model of fetal programming of adult glucose intolerance exhibiting diminished perivenous glucokinase (GK) activity. We now show that perivenous glucose uptake rises with increasing glucose concentration (0-8 mmol/l) in control but not MLP liver, indicating that GK is flux-generating. The data demonstrate that acute control of hepatic glucose output is principally achieved by increasing perivenous glucose uptake, with rising glucose concentration during refeeding, rather than by downregulation of gluconeogenesis, which occurs in different hepatocytes. Consistent with these observations, glycogen synthesis in vivo commenced in the perivenous cells during refeeding, MLP livers accumulating less glycogen than controls. GK gene transcription was unchanged in MLP liver, the data supporting a recently proposed posttranscriptional model of GK regulation involving nuclear-cytoplasmic transport. The results are pertinent to impaired regulation of hepatic glucose output in type 2 diabetes, which could arise from diminished GK-mediated glucose uptake rather than increased gluconeogenesis.

  1. Glutathione redox regulates airway hyperresponsiveness and airway inflammation in mice.

    PubMed

    Koike, Yoko; Hisada, Takeshi; Utsugi, Mitsuyoshi; Ishizuka, Tamotsu; Shimizu, Yasuo; Ono, Akihiro; Murata, Yukie; Hamuro, Junji; Mori, Masatomo; Dobashi, Kunio

    2007-09-01

    Glutathione is the major intracellular redox buffer. We have shown that glutathione redox status, which is the balance between intracellular reduced (GSH) and oxidized (GSSG) glutathione, in antigen-presenting cells (APC) regulates the helper T cell type 1 (Th1)/Th2 balance due to the production of IL-12. Bronchial asthma is a typical Th2 disease. Th2 cells and Th2 cytokines are characteristic of asthma and trigger off an inflammation. Accordingly, we studied the effects of the intracellular glutathione redox status on airway hyperresponsiveness (AHR) and allergen-induced airway inflammation in a mouse model of asthma. We used gamma-Glutamylcysteinylethyl ester (gamma-GCE), which is a membrane-permeating GSH precursor, to elevate the intracellular GSH level and GSH/GSSG ratio of mice. In vitro, gamma-GCE pretreatment of human monocytic THP-1 cells elevated the GSH/GSSG ratio and enhanced IL-12(p70) production induced by LPS. In the mouse asthma model, intraperitoneal injection of gamma-GCE elevated the GSH/GSSG ratio of lung tissue and reduced AHR. gamma-GCE reduced levels of IL-4, IL-5, IL-10, and the chemokines eotaxin and RANTES (regulated on activation, normal T cell expressed and secreted) in bronchoalveolar lavage fluid, whereas it enhanced the production of IL-12 and IFN-gamma. Histologically, gamma-GCE suppressed eosinophils infiltration. Interestingly, we also found that gamma-GCE directly inhibited chemokine-induced eosinophil chemotaxis without affecting eotaxin receptor chemokine receptor 3 (CCR3) expressions. Taken together, these findings suggest that changing glutathione redox balance, increase in GSH level, and the GSH/GSSG ratio by gamma-GCE, ameliorate bronchial asthma by altering the Th1/Th2 imbalance through IL-12 production from APC and suppressing chemokine production and eosinophil migration itself.

  2. The role of pancreatic insulin secretion in neonatal glucoregulation. II. Infants with disordered blood glucose homoeostasis.

    PubMed Central

    Hawdon, J M; Aynsley-Green, A; Bartlett, K; Ward Platt, M P

    1993-01-01

    Some neonates, such as those who are preterm or small for dates, become hypoglycaemic or hyperglycaemic. These disorders represent a failure of neonatal metabolic adaptation, but the underlying mechanisms are unclear. Data from studies of hypoglycaemic and hyperglycaemic infants were reviewed in the light of new data from studies of healthy neonates. Data from 28 neonates, who had disordered blood glucose homoeostasis, were analysed to determine the interrelationships between circulating concentrations of glucose, intermediary metabolites, glucagon and insulin, and glucose production rates. Blood glucose concentrations ranged from 2.5 to 26.1 mmol/l, and glucose production rates from 0 to 19.2 mg/kg/min. Blood glucose concentrations were positively related to intravenous glucose infusion rates and to glucose production rates. A negative relationship existed between plasma glucagon and blood glucose concentrations, but there was a wide variation in plasma insulin levels at all blood glucose concentrations. No relationship between either plasma insulin or glucagon concentration and glucose production rate was shown. It is concluded that in neonates with disordered blood glucose homoeostasis, blood glucose concentration is influenced by the rate of administration of glucose, with less precise internal control mechanisms than older subjects. This emphasises the importance of blood glucose monitoring and careful prescribing of exogenous glucose by clinicians caring for such infants. PMID:8466263

  3. Noninvasive Continuous Monitoring of Tear Glucose Using Glucose-Sensing Contact Lenses.

    PubMed

    Ascaso, Francisco J; Huerva, Valentín

    2016-04-01

    : The incidence of diabetes mellitus is dramatically increasing in the developed countries. Tight control of blood glucose concentration is crucial to diabetic patients to prevent microvascular complications. Self-monitoring of blood glucose is widely used for controlling blood glucose levels and usually performed by an invasive test using a portable glucometer. Many technologies have been developed over the past decades with the purpose of obtaining a continuous physiological glycemic monitoring. A contact lens is the ideal vehicle for continuous tear glucose monitoring of glucose concentration in tear film. There are several research groups that are working in the development of contact lenses with embedded biosensors for continuously and noninvasively monitoring tear glucose levels. Although numerous aspects must be improved, contact lens technology is one step closer to helping diabetic subjects better manage their condition, and these contact lenses will be able to measure the level of glucose in the wearer's tears and communicate the information to a mobile phone or computer. This article reviews studies on ocular glucose and its monitoring methods as well as the attempts to continuously monitor the concentration of tear glucose by using contact lens-based sensors.

  4. Wireless glucose monitoring watch enabled by an implantable self-sustaining glucose sensor system

    NASA Astrophysics Data System (ADS)

    Rai, Pratyush; Varadan, Vijay K.

    2012-10-01

    Implantable glucose sensors can measure real time blood glucose as compared to conventional techniques involving drawing blood samples and in-vitro processing. An implantable sensor requires energy source for operation with wire inout provision for power and sending signals. Implants capable of generation-transmission of sensory signals, with minimal or no power requirement, can solve this problem. An implantable nanosensor design has been presented here, which can passively detect glucose concentration in blood stream and transmit data to a wearable receiver-recorder system or a watch. The glucose sensitive component is a redox pair of electrodes that generates voltage proportional to glucose concentration. The bio-electrode, made of carbon nanotubes-enzyme nanocluster, has been investigated because of the large surface area for taping electrical signals. This glucose sensor can charge a capacitor, which can be a part of a LCR resonance/inductive coupling based radio frequency (RF) sensor telemetry. Such a system can measure change in glucose concentration by the induced frequency shift in the LCR circuit. A simultaneous power transmission and signal transmission can be achieved by employing two separate LCR oscillating loops, one for each operation. The corresponding coupling LCR circuits can be housed in the wearable receiving watch unit. The data logged in this glucose monitoring watch can be instrumental in managing blood glucose as trigger for an insulin dispensing payload worn on person or implanted.

  5. Respiratory syncytial virus infection increases chlorine-induced airway hyperresponsiveness

    PubMed Central

    Song, Weifeng; Yu, Zhihong; Doran, Stephen F.; Ambalavanan, Namasivayam; Steele, Chad; Garantziotis, Stavros

    2015-01-01

    Exposure to chlorine (Cl2) damages airway and alveolar epithelia resulting in acute lung injury and reactive airway hyperresponsiveness (AHR) to methacholine. However, little is known about the effect of preexisting respiratory disease on Cl2-induced lung injury. By using a murine respiratory syncytial virus (RSV) infection model, we found that preexisting RSV infection increases Cl2 (187 ppm for 30 min)-induced lung inflammation and airway AHR at 24 h after exposure (5 days after infection). RSV infection and Cl2 exposure synergistically induced oxygen desaturation and neutrophil infiltration and increased MCP-1, MIP-1β, IL-10, IFN-γ, and RANTES concentrations in the bronchoalveolar lavage fluid (BALF). In contrast, levels of type 2 cytokines (i.e., IL-4, IL-5, IL-9, and IL-13) were not significantly affected by either RSV infection or Cl2 exposure. Cl2 exposure, but not RSV infection, induced AHR to methacholine challenge as measured by flexiVent. Moreover, preexisting RSV infection amplified BALF levels of hyaluronan (HA) and AHR. The Cl2-induced AHR was mitigated by treatment with inter-α-trypsin inhibitor antibody, which inhibits HA signaling, suggesting a mechanism of HA-mediated AHR from exacerbated oxidative injury. Our results show for the first time that preexisting RSV infection predisposes the lung to Cl2-induced injury. These data emphasize the necessity for further research on the effects of Cl2 in vulnerable populations and the development of appropriate treatments. PMID:26071553

  6. Expression of interleukin-18 by porcine airway and intestinal epithelium.

    PubMed

    Muneta, Yoshihiro; Goji, Noriko; Tsuji, Noriko M; Mikami, Osamu; Shimoji, Yoshihiro; Nakajima, Yasuyuki; Yokomizo, Yuichi; Mori, Yasuyuki

    2002-08-01

    In this study, we investigated the expression of interleukin-18 (IL-18) in porcine airway and intestinal epithelium. We found constitutive protein expression of precursor IL-18 in primary culture of porcine airway epithelium. Immunohistochemical staining revealed that porcine IL-18 was localized in the porcine airway epithelium and that it was significantly upregulated with experimental endotoxemia induced by Escherichia coli lipopolysaccharide (LPS) inoculation. We also confirmed by immunohistochemical staining that IL-18 was expressed in porcine intestinal epithelial cells. Moreover, the concentration of IL-18 in intestinal cell lysates of 1-day-old piglets was about 3-fold and 6-fold less than that in those of 1-month-old and 6-month-old piglets, respectively. Exogenous IL-18 was able to induce interferon-gamma (IFN-gamma) in the peripheral blood of 1-day-old piglets, whereas concanavalin A (ConA) was not able to induce IFN-gamma in the same condition. These results suggest that mucosal epithelial cells are among the major sources of IL-18 in pig and that IL-18 may be useful as a therapeutic agent for the enhancement of immune responses and as a vaccine adjuvant, especially in neonatal piglets.

  7. Educating the Educator: Teaching Airway Adjunct Techniques in Athletic Training

    ERIC Educational Resources Information Center

    Berry, David C.; Seitz, S. Robert

    2011-01-01

    The 5th edition of the "Athletic Training Education Competencies" ("Competencies") now requires athletic training educators (ATEs) to introduce into the curriculum various types of airway adjuncts including: (1) oropharyngeal airways (OPA), (2) nasopharyngeal airways (NPA), (3) supraglottic airways (SGA), and (4) suction. The addition of these…

  8. Airway adequacy, head posture, and craniofacial morphology.

    PubMed

    Solow, B; Siersbaek-Nielsen, S; Greve, E

    1984-09-01

    Previous studies of different samples have demonstrated associations between craniocervical angulation and craniofacial morphology, between airway obstruction by adenoids and craniofacial morphology, and between airway obstruction and craniocervical angulation. A hypothesis to account for the different sets of associations was suggested by Solow and Kreiborg in 1977. In the present study, the three sets of associations were examined in a single group of nonpathologic subjects with no history of airway obstruction. Cephalometric radiographs taken in the natural head position and rhinomanometric recordings were obtained from twenty-four children 7 to 9 years of age. Correlations were calculated between twenty-seven morphologic, eight postural, and two airway variables. A large craniocervical angle was, on the average, seen in connection with small mandibular dimensions, mandibular retrognathism, and a large mandibular inclination. Obstructed nasopharyngeal airways (defined as a small pm-ad 2 radiographic distance and a large nasal respiratory resistance, NRR, determined rhinomanometrically) were, on the average, seen in connection with a large craniocervical angle and with small mandibular dimensions, mandibular retrognathism, a large mandibular inclination, and retroclination of the upper incisors. The observed correlations were in agreement with the predicted pattern of associations between craniofacial morphology, craniocervical angulation, and airway resistance, thus suggesting the simultaneous presence of such associations in the sample of nonpathologic subjects with no history of airway obstruction.

  9. Comparison of analysis methods for airway quantification

    NASA Astrophysics Data System (ADS)

    Odry, Benjamin L.; Kiraly, Atilla P.; Novak, Carol L.; Naidich, David P.

    2012-03-01

    Diseased airways have been known for several years as a possible contributing factor to airflow limitation in Chronic Obstructive Pulmonary Diseases (COPD). Quantification of disease severity through the evaluation of airway dimensions - wall thickness and lumen diameter - has gained increased attention, thanks to the availability of multi-slice computed tomography (CT). Novel approaches have focused on automated methods of measurement as a faster and more objective means that the visual assessment routinely employed in the clinic. Since the Full-Width Half-Maximum (FWHM) method of airway measurement was introduced two decades ago [1], several new techniques for quantifying airways have been detailed in the literature, but no approach has truly become a standard for such analysis. Our own research group has presented two alternative approaches for determining airway dimensions, one involving a minimum path and the other active contours [2, 3]. With an increasing number of techniques dedicated to the same goal, we decided to take a step back and analyze the differences of these methods. We consequently put to the test our two methods of analysis and the FWHM approach. We first measured a set of 5 airways from a phantom of known dimensions. Then we compared measurements from the three methods to those of two independent readers, performed on 35 airways in 5 patients. We elaborate on the differences of each approach and suggest conclusions on which could be defined as the best one.

  10. Glucose test (image)

    MedlinePlus

    ... person with diabetes constantly manages their blood's sugar (glucose) levels. After a blood sample is taken and tested, it is determined whether the glucose levels are low or high. Following your health ...

  11. Blood Glucose Monitoring Devices

    MedlinePlus

    ... the Bar for Blood Glucose Meter Performance Recalls & Alerts Shasta Technologies GenStrip Blood Glucose Test Strips May ... Latest Recalls Report an Adverse Event MedWatch Safety Alerts News Releases Consumer Updates About FDA Contact FDA ...

  12. Molecular Pathophysiology of Hepatic Glucose Production

    PubMed Central

    Sharabi, Kfir; Tavares, Clint D. J.; Rines, Amy K.; Puigserver, Pere

    2015-01-01

    Maintaining blood glucose concentration within a relatively narrow range through periods of fasting or excess nutrient availability is essential to the survival of the organism. This is achieved through an intricate balance between glucose uptake and endogenous glucose production to maintain constant glucose concentrations. The liver plays a major role in maintaining normal whole body glucose levels by regulating the processes of de novo glucose production (gluconeogenesis) and glycogen breakdown (glycogenolysis), thus controlling the levels of hepatic glucose release. Aberrant regulation of hepatic glucose production (HGP) can result in deleterious clinical outcomes, and excessive HGP is a major contributor to the hyperglycemia observed in Type 2 diabetes mellitus (T2DM). Indeed, adjusting glycaemia as close as possible to a non-diabetic range is the foremost objective in the medical treatment of patients with T2DM and is currently achieved in the clinic primarily through suppression of HGP. Here, we review the molecular mechanisms controlling HGP in response to nutritional and hormonal signals and discuss how these signals are altered in T2DM. PMID:26549348

  13. Molecular pathophysiology of hepatic glucose production.

    PubMed

    Sharabi, Kfir; Tavares, Clint D J; Rines, Amy K; Puigserver, Pere

    2015-12-01

    Maintaining blood glucose concentration within a relatively narrow range through periods of fasting or excess nutrient availability is essential to the survival of the organism. This is achieved through an intricate balance between glucose uptake and endogenous glucose production to maintain constant glucose concentrations. The liver plays a major role in maintaining normal whole body glucose levels by regulating the processes of de novo glucose production (gluconeogenesis) and glycogen breakdown (glycogenolysis), thus controlling the levels of hepatic glucose release. Aberrant regulation of hepatic glucose production (HGP) can result in deleterious clinical outcomes, and excessive HGP is a major contributor to the hyperglycemia observed in Type 2 diabetes mellitus (T2DM). Indeed, adjusting glycemia as close as possible to a non-diabetic range is the foremost objective in the medical treatment of patients with T2DM and is currently achieved in the clinic primarily through suppression of HGP. Here, we review the molecular mechanisms controlling HGP in response to nutritional and hormonal signals and discuss how these signals are altered in T2DM.

  14. Glucose measurement in interstitial fluid by microdialysis for the calibration of minimally invasive blood glucose monitoring

    NASA Astrophysics Data System (ADS)

    Li, Dachao; Wang, Ridong; Chong, Hao; Liu, Yu; Xu, Kexin

    2013-03-01

    According to the requirement of the calibration in minimally invasive blood glucose monitoring, a method based on microdialysis was presented to monitor glucose level in interstitial fluid continuously. An experimental system simulating the continuous change of glucose concentration in vivo was built. The influences on recovery of microdialysis caused by flow rate, glucose concentration, and temperature etc. were studied. The results led to the conclusion that the recovery fell by 71.7% when perfusion rate increased from 0.3 μL/min to 3.0 μL/min, while the different concentrations of glucose solutions scarcely contribute to the recovery instead, and the temperatures from 25 to 58 °C caused the recovery to increase by 34.6%.

  15. Airway smooth muscle growth in asthma: proliferation, hypertrophy, and migration.

    PubMed

    Bentley, J Kelley; Hershenson, Marc B

    2008-01-01

    Increased airway smooth muscle mass is present in fatal and non-fatal asthma. However, little information is available regarding the cellular mechanism (i.e., hyperplasia vs. hypertrophy). Even less information exists regarding the functional consequences of airway smooth muscle remodeling. It would appear that increased airway smooth muscle mass would tend to increase airway narrowing and airflow obstruction. However, the precise effects of increased airway smooth muscle mass on airway narrowing are not known. This review will consider the evidence for airway smooth muscle cell proliferation and hypertrophy in asthma, potential functional effects, and biochemical mechanisms.

  16. Myeloid sarcoma causing airway obstruction

    PubMed Central

    Krause, John R.

    2017-01-01

    Myeloid sarcoma is an extramedullary collection of blasts of the myeloid series that partially or totally effaces the architecture of the tissue in which it is found. These tumors have been described in many sites of the body, but the skin, lymph nodes, gastrointestinal tract, bone, soft tissue, and testes are most common. They can arise in a patient following the diagnosis of acute myeloid leukemia, but they may also be precursors of leukemia and should be considered diagnostic for acute myeloid leukemia. The differential diagnosis of this neoplasm includes malignant lymphoma, with which it is often mistaken, leading to diagnostic and therapeutic delays. We present the case of an 84-year-old African American man with a history of renal disease secondary to hypertension and coronary artery disease without any prior history of malignancies who presented with airway obstruction. He was diagnosed with a myeloid sarcoma of the mediastinum compressing his trachea.

  17. The Development and Application of Airway Devices in China

    PubMed Central

    Chen, Xiangdong; Ma, Wuhua; Liu, Renyu; Yao, Shanglong

    2017-01-01

    Airway management is one of the most important tasks for anesthesiologists. Anesthesiologists are experts in airway management and have made tremendous contribution to the development of the airway devices. Chinese anesthesiologists have made significant contribution in introducing advanced airway management and developing innovative techniques and devices for airway management in China. This article overviews the development and application of airway devices in China as well as the dedication and contribution of Chinese experts in the development of novel airway devices. With the development of science and technology accompanied by the advanced knowledge in airway management, more effective and safe artificial airways will be developed for clinical practice. The authors believe that Chinese experts will continue their outstanding contribution to the development of innovative airway devices, systems and knowledge. PMID:28191485

  18. Pharmacology of airway afferent nerve activity

    PubMed Central

    Undem, Bradley J; Carr, Michael J

    2001-01-01

    Afferent nerves in the airways serve to regulate breathing pattern, cough, and airway autonomic neural tone. Pharmacologic agents that influence afferent nerve activity can be subclassified into compounds that modulate activity by indirect means (e.g. bronchial smooth muscle spasmogens) and those that act directly on the nerves. Directly acting agents affect afferent nerve activity by interacting with various ion channels and receptors within the membrane of the afferent terminals. Whether by direct or indirect means, most compounds that enter the airspace will modify afferent nerve activity, and through this action alter airway physiology. PMID:11686889

  19. Firefighting acutely increases airway responsiveness.

    PubMed

    Sherman, C B; Barnhart, S; Miller, M F; Segal, M R; Aitken, M; Schoene, R; Daniell, W; Rosenstock, L

    1989-07-01

    The acute effects of the products of combustion and pyrolysis on airway responsiveness among firefighters are poorly documented. To study this relationship, spirometry and methacholine challenge testing (MCT) were performed on 18 active Seattle firefighters before and 5 to 24 h after firefighting. Body plethysmography was used to measure changes in specific airway conductance (SGaw), and results of MCT were analyzed using PD35-SGaw, the cumulative dose causing a 35% decrease in SGaw. Subjects who did not react by the end of the protocol were assigned a value of 640 inhalational units, the largest cumulative dose. Fire exposure was defined as the total time (hours) spent without a self-contained breathing apparatus at the firesite and was categorized as mild (less than 1 h, n = 7), moderate (1 to 2 h, n = 5), or severe (greater than 2 h, n = 6). Mean age of the 18 firefighters was 36.7 +/- 6.7 yr (range, 25 to 51), with a mean of 9.1 +/- 7.9 active years in the trade (range, zero to 22). None was known to be asthmatic. After firefighting, FEV1 % predicted (%pred) and FEF25-75 %pred significantly decreased by means of 3.4 +/- 1.1% and 5.6 +/- 2.6%, respectively. The mean decline in PD35-SGaw after firefighting was 184.5 +/- 53.2 units (p = 0.003). This observed decline in PD35-SGaw could not be explained by decrements in prechallenge SGaw, FEV1, or FVC.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. All about Blood Glucose

    MedlinePlus

    Toolkit No. 15 All About Blood Glucose Keeping your blood glucose (sugar)in your target range can prevent or delay the health problems ... Diabetes Association, Inc. 1/15 Toolkit No.15: All About Blood Glucose continued team about when and ...

  1. Effect of dry- versus wet-autoclaving of spray-dried egg albumen compared with casein as protein sources on apparent nitrogen and energy balance, plasma urea nitrogen and glucose concentrations, and growth performance of neonatal swine.

    PubMed

    Watkins, K L; Veum, T L

    2010-08-01

    Forty crossbred neonatal pigs with an average initial age of 4 d and BW of 2.16 kg were used in a 28-d experiment to evaluate the nutritional effects of autoclaving a commercial sugar-free, spray-dried egg albumen (EA) compared with casein. Basal diet protein sources were lactic acid casein and EA. Two more dietary treatments were made by replacing the EA with dry-autoclaved EA (DAEA) or wet-autoclaved EA (WAEA, EA and water mixed in a 1.0:1.2 ratio before autoclaving). The DAEA and WAEA were autoclaved at 121 degrees C and 1.75 kg/cm(2) pressure for 30 min, and WAEA was oven-dried after autoclaving. Analyzed trypsin inhibitor units/mg of EA, DAEA, and WAEA were 535.0, 9.0, and 6.5, respectively. Pigs were fed the diets in gruel form to appetite in individual metabolism cages every 2 h during the experiment. Blood samples were taken on d 7, 14, and 21, and total urine and fecal grab-samples were collected from d 14 to 21 of the experiment. Response criteria were N and energy balance, plasma urea N (PUN) and glucose concentrations, and growth performance. The WAEA was a higher quality protein source for neonatal pigs than DAEA. Pigs fed the diet containing WAEA absorbed and retained more (P < 0.05) grams of N/d, had higher (P < 0.05) percentages of N and energy that were absorbed and retained/intake, had lower (P < 0.05) concentrations of PUN overall, and had higher (P < 0.05) ADG and G:F than pigs fed the diet containing DAEA. Most response criteria of pigs fed the diets containing DAEA or EA were not different, although pigs fed the diet containing DAEA had lower (P < 0.05) overall PUN concentrations, and pigs fed the diet containing EA had higher (P < 0.05) percentages of energy absorbed and retained/intake, and higher ADG and G:F than pigs fed the diet containing DAEA. Growth performance was not different for pigs fed the diets containing WAEA or casein. However, pigs fed the diet containing casein excreted less (P < 0.05) fecal N, retained more (P < 0/05) grams

  2. Ozone at high-pollution urban levels causes airway hyperresponsiveness to substance P but not to other agonists.

    PubMed

    Segura, P; Montaño, L M; Bazán-Perkins, B; Gustin, P; Vargas, M H

    1997-06-06

    Ozone (O(3)) causes airway hyperresponsiveness, but few studies have evaluated this effect at urban concentrations. In this work dose-response curves to intravenous acetylcholine, histamine or substance P were performed in guinea pigs with or without previous exposure to O(3) (0.15, 0.3, 0.6 or 1.2 ppm for 4 h, 16-18 h before the studies). We found airway hyperresponsiveness to histamine, but not to acetylcholine, only after 1.2 ppm O(3). By contrast, airway hyperresponsiveness to substance P was developed at O(3) levels encountered in highly-polluted cities (0.3 ppm). These results suggest that excitatory non-adrenergic non-cholinergic responses could be affected by air pollution, and that substance P is a useful pharmacological tool for evaluating the airway hyperresponsiveness induced by low O(3) concentrations.

  3. Ambulatory glucose profile: Flash glucose monitoring.

    PubMed

    Kalra, Sanjay; Gupta, Yashdeep

    2015-12-01

    Ambulatory glucose profile (AGP) is a novel way of assessing glycaemic levels on a 24 hour basis, through a minimally invasive method, known as flash glucose monitoring. This review describes the unique features of AGP, differentiates it from existing methods of glucose monitoring, and explains how it helps pursue the glycaemic pentad. The review suggests pragmatic usage of this technology, including pre-test, intra-test, and post-test counselling, and lists specific clinical scenarios where the investigation seems to be of immense benefit.

  4. Glucose uptake saturation explains glucose kinetics profiles measured by different tests.

    PubMed

    Bizzotto, Roberto; Natali, Andrea; Gastaldelli, Amalia; Muscelli, Elza; Krssak, Martin; Brehm, Attila; Roden, Michael; Ferrannini, Ele; Mari, Andrea

    2016-08-01

    It is known that for a given insulin level glucose clearance depends on glucose concentration. However, a quantitative representation of the concomitant effects of hyperinsulinemia and hyperglycemia on glucose clearance, necessary to describe heterogeneous tests such as euglycemic and hyperglycemic clamps and oral tests, is lacking. Data from five studies (123 subjects) using a glucose tracer and including all the above tests in normal and diabetic subjects were collected. A mathematical model was developed in which glucose utilization was represented as a Michaelis-Menten function of glucose with constant Km and insulin-controlled Vmax, consistently with the basic notions of glucose transport. Individual values for the model parameters were estimated using a population approach. Tracer data were accurately fitted in all tests. The estimated Km was 3.88 (2.83-5.32) mmol/l [median (interquartile range)]. Median model-derived glucose clearance at 600 pmol/l insulin was reduced from 246 to 158 ml·min(-1)·m(-2) when glucose was raised from 5 to 10 mmol/l. The model reproduced the characteristic lack of increase in glucose clearance when moderate hyperinsulinemia was accompanied by hyperglycemia. In all tests, insulin sensitivity was inversely correlated with BMI, as expected (R(2) = 0.234, P = 0.0001). In conclusion, glucose clearance in euglycemic and hyperglycemic clamps and oral tests can be described with a unifying model, consistent with the notions of glucose transport and able to reproduce the suppression of glucose clearance due to hyperglycemia observed in previous studies. The model may be important for the design of reliable glucose homeostasis simulators.

  5. Accuracy of Handheld Blood Glucose Meters at High Altitude

    PubMed Central

    de Vries, Suzanna T.; Fokkert, Marion J.; Dikkeschei, Bert D.; Rienks, Rienk; Bilo, Karin M.; Bilo, Henk J. G.

    2010-01-01

    Background Due to increasing numbers of people with diabetes taking part in extreme sports (e.g., high-altitude trekking), reliable handheld blood glucose meters (BGMs) are necessary. Accurate blood glucose measurement under extreme conditions is paramount for safe recreation at altitude. Prior studies reported bias in blood glucose measurements using different BGMs at high altitude. We hypothesized that glucose-oxidase based BGMs are more influenced by the lower atmospheric oxygen pressure at altitude than glucose dehydrogenase based BGMs. Methodology/Principal Findings Glucose measurements at simulated altitude of nine BGMs (six glucose dehydrogenase and three glucose oxidase BGMs) were compared to glucose measurement on a similar BGM at sea level and to a laboratory glucose reference method. Venous blood samples of four different glucose levels were used. Moreover, two glucose oxidase and two glucose dehydrogenase based BGMs were evaluated at different altitudes on Mount Kilimanjaro. Accuracy criteria were set at a bias <15% from reference glucose (when >6.5 mmol/L) and <1 mmol/L from reference glucose (when <6.5 mmol/L). No significant difference was observed between measurements at simulated altitude and sea level for either glucose oxidase based BGMs or glucose dehydrogenase based BGMs as a group phenomenon. Two GDH based BGMs did not meet set performance criteria. Most BGMs are generally overestimating true glucose concentration at high altitude. Conclusion At simulated high altitude all tested BGMs, including glucose oxidase based BGMs, did not show influence of low atmospheric oxygen pressure. All BGMs, except for two GDH based BGMs, performed within predefined criteria. At true high altitude one GDH based BGM had best precision and accuracy. PMID:21103399

  6. Estrogen effects on human airway smooth muscle involve cAMP and protein kinase A.

    PubMed

    Townsend, Elizabeth A; Sathish, Venkatachalem; Thompson, Michael A; Pabelick, Christina M; Prakash, Y S

    2012-11-15

    Clinically observed differences in airway reactivity and asthma exacerbations in women at different life stages suggest a role for sex steroids in modulating airway function although their targets and mechanisms of action are still being explored. We have previously shown that clinically relevant concentrations of exogenous estrogen acutely decrease intracellular calcium ([Ca(2+)](i)) in human airway smooth muscle (ASM), thereby facilitating bronchodilation. In this study, we hypothesized that estrogens modulate cyclic nucleotide regulation, resulting in decreased [Ca(2+)](i) in human ASM. In Fura-2-loaded human ASM cells, 1 nM 17β-estradiol (E(2)) potentiated the inhibitory effect of the β-adrenoceptor (β-AR) agonist isoproterenol (ISO; 100 nM) on histamine-mediated Ca(2+) entry. Inhibition of protein kinase A (PKA) activity (KT5720; 100 nM) attenuated E(2) effects on [Ca(2+)](i). Acute treatment with E(2) increased cAMP levels in ASM cells comparable to that of ISO (100 pM). In acetylcholine-contracted airways from female guinea pigs or female humans, E(2) potentiated ISO-induced relaxation. These novel data suggest that, in human ASM, physiologically relevant concentrations of estrogens act via estrogen receptors (ERs) and the cAMP pathway to nongenomically reduce [Ca(2+)](i), thus promoting bronchodilation. Activation of ERs may be a novel adjunct therapeutic avenue in reactive airway diseases in combination with established cAMP-activating therapies such as β(2)-agonists.

  7. Injury Induces Localized Airway Increases in Pro-Inflammatory Cytokines in Humans and Mice

    PubMed Central

    Jonker, Mark A.; Hermsen, Joshua L.; Gomez, F. Enrique; Sano, Yoshifumi

    2011-01-01

    Abstract Background Secretory immunoglobulin A (sIgA) increases in the airways of humans and mice after injury to protect against infection. The pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 are linked molecularly to sIgA production and secretion and are required for sIgA increases in the airway after injury in a mouse model. We investigated the injury effect on airway and serum concentrations to determine the source of the cytokines involved in the airway IgA response. Methods In the first experiment, TNF-α, IL-1β, and IL-6 concentrations in bronchoalveolar lavage (BAL) fluid and serum obtained from 11 ventilated trauma patients within 30 h of admission were compared with those in eight elective surgical patients. In the second experiment, male ICR mice received no injury (n = 7) or injury with sham celiotomy and neck incisions (n = 8) with sacrifice of all animals at 8 h for BAL fluid and serum cytokine measurements by enzyme-linked immunosorbent assay. Results Injured patients had significantly higher BAL fluid and serum TNF-α, IL-1β, and IL-6 concentrations, with greater increases in the BAL fluid than in the serum. Injured mice had significantly increased BAL fluid concentrations of TNF-α, IL-1β, and IL-6 without significant changes in serum TNF-α or IL-1β. Serum IL-6 increased significantly. Conclusions Injury significantly increases human and mouse airway TNF-α, IL-1β, and IL-6. Increases are greater in the airway than in serum, implying a local rather than a systemic stress response to injury. PMID:21166596

  8. Regulation of eosinophilia and allergic airway inflammation by the glycan-binding protein galectin-1.

    PubMed

    Ge, Xiao Na; Ha, Sung Gil; Greenberg, Yana G; Rao, Amrita; Bastan, Idil; Blidner, Ada G; Rao, Savita P; Rabinovich, Gabriel A; Sriramarao, P

    2016-08-16

    Galectin-1 (Gal-1), a glycan-binding protein with broad antiinflammatory activities, functions as a proresolving mediator in autoimmune and chronic inflammatory disorders. However, its role in allergic airway inflammation has not yet been elucidated. We evaluated the effects of Gal-1 on eosinophil function and its role in a mouse model of allergic asthma. Allergen exposure resulted in airway recruitment of Gal-1-expressing inflammatory cells, including eosinophils, as well as increased Gal-1 in extracellular spaces in the lungs. In vitro, extracellular Gal-1 exerted divergent effects on eosinophils that were N-glycan- and dose-dependent. At concentrations ≤0.25 µM, Gal-1 increased eosinophil adhesion to vascular cell adhesion molecule-1, caused redistribution of integrin CD49d to the periphery and cell clustering, but inhibited ERK(1/2) activation and eotaxin-1-induced migration. Exposure to concentrations ≥1 µM resulted in ERK(1/2)-dependent apoptosis and disruption of the F-actin cytoskeleton. At lower concentrations, Gal-1 did not alter expression of adhesion molecules (CD49d, CD18, CD11a, CD11b, L-selectin) or of the chemokine receptor CCR3, but decreased CD49d and CCR3 was observed in eosinophils treated with higher concentrations of this lectin. In vivo, allergen-challenged Gal-1-deficient mice exhibited increased recruitment of eosinophils and CD3(+) T lymphocytes in the airways as well as elevated peripheral blood and bone marrow eosinophils relative to corresponding WT mice. Further, these mice had an increased propensity to develop airway hyperresponsiveness and displayed significantly elevated levels of TNF-α in lung tissue. This study suggests that Gal-1 can limit eosinophil recruitment to allergic airways and suppresses airway inflammation by inhibiting cell migration and promoting eosinophil apoptosis.

  9. Regulation of eosinophilia and allergic airway inflammation by the glycan-binding protein galectin-1

    PubMed Central

    Ge, Xiao Na; Ha, Sung Gil; Greenberg, Yana G.; Rao, Amrita; Bastan, Idil; Blidner, Ada G.; Rao, Savita P.; Rabinovich, Gabriel A.; Sriramarao, P.

    2016-01-01

    Galectin-1 (Gal-1), a glycan-binding protein with broad antiinflammatory activities, functions as a proresolving mediator in autoimmune and chronic inflammatory disorders. However, its role in allergic airway inflammation has not yet been elucidated. We evaluated the effects of Gal-1 on eosinophil function and its role in a mouse model of allergic asthma. Allergen exposure resulted in airway recruitment of Gal-1–expressing inflammatory cells, including eosinophils, as well as increased Gal-1 in extracellular spaces in the lungs. In vitro, extracellular Gal-1 exerted divergent effects on eosinophils that were N-glycan– and dose-dependent. At concentrations ≤0.25 µM, Gal-1 increased eosinophil adhesion to vascular cell adhesion molecule-1, caused redistribution of integrin CD49d to the periphery and cell clustering, but inhibited ERK(1/2) activation and eotaxin-1–induced migration. Exposure to concentrations ≥1 µM resulted in ERK(1/2)-dependent apoptosis and disruption of the F-actin cytoskeleton. At lower concentrations, Gal-1 did not alter expression of adhesion molecules (CD49d, CD18, CD11a, CD11b, L-selectin) or of the chemokine receptor CCR3, but decreased CD49d and CCR3 was observed in eosinophils treated with higher concentrations of this lectin. In vivo, allergen-challenged Gal-1–deficient mice exhibited increased recruitment of eosinophils and CD3+ T lymphocytes in the airways as well as elevated peripheral blood and bone marrow eosinophils relative to corresponding WT mice. Further, these mice had an increased propensity to develop airway hyperresponsiveness and displayed significantly elevated levels of TNF-α in lung tissue. This study suggests that Gal-1 can limit eosinophil recruitment to allergic airways and suppresses airway inflammation by inhibiting cell migration and promoting eosinophil apoptosis. PMID:27457925

  10. Chemotaxis and Binding of Pseudomonas aeruginosa to Scratch-Wounded Human Cystic Fibrosis Airway Epithelial Cells

    PubMed Central

    Schwarzer, Christian; Fischer, Horst; Machen, Terry E.

    2016-01-01

    Confocal imaging was used to characterize interactions of Pseudomonas aeruginosa (PA, expressing GFP or labeled with Syto 11) with CF airway epithelial cells (CFBE41o-, grown as confluent monolayers with unknown polarity on coverglasses) in control conditions and following scratch wounding. Epithelia and PAO1-GFP or PAK-GFP (2 MOI) were incubated with Ringer containing typical extracellular salts, pH and glucose and propidium iodide (PI, to identify dead cells). PAO1 and PAK swam randomly over and did not bind to nonwounded CFBE41o- cells. PA migrated rapidly (began within 20 sec, maximum by 5 mins) and massively (10–80 fold increase, termed “swarming”), but transiently (random swimming after 15 mins), to wounds, particularly near cells that took up PI. Some PA remained immobilized on cells near the wound. PA swam randomly over intact CFBE41o- monolayers and wounded monolayers that had been incubated with medium for 1 hr. Expression of CFTR and altered pH of the media did not affect PA interactions with CFBE41o- wounds. In contrast, PAO1 swarming and immobilization along wounds was abolished in PAO1 (PAO1ΔcheYZABW, no expression of chemotaxis regulatory components cheY, cheZ, cheA, cheB and cheW) and greatly reduced in PAO1 that did not express amino acid receptors pctA, B and C (PAO1ΔpctABC) and in PAO1 incubated in Ringer containing a high concentration of mixed amino acids. Non-piliated PAKΔpilA swarmed normally towards wounded areas but bound infrequently to CFBE41o- cells. In contrast, both swarming and binding of PA to CFBE41o- cells near wounds were prevented in non-flagellated PAKΔfliC. Data are consistent with the idea that (i) PA use amino acid sensor-driven chemotaxis and flagella-driven swimming to swarm to CF airway epithelial cells near wounds and (ii) PA use pili to bind to epithelial cells near wounds. PMID:27031335

  11. Abdominal adiposity and obstructive airway disease: testing insulin resistance and sleep disordered breathing mechanisms

    PubMed Central

    2012-01-01

    Background This study examined associations of abdominal adiposity with lung function, asthma symptoms and current doctor-diagnosed asthma and mediation by insulin resistance (IR) and sleep disordered breathing (SDB). Methods A random sample of 2500 households was drawn from the community of Whyalla, South Australia (The Whyalla Intergenerational Study of Health, WISH February 2008 - July 2009). Seven-hundred twenty-two randomly selected adults (≥18 years) completed clinical protocols (32.2% response rate). Lung function was measured by spirometry. Post-bronchodilator FEV1/FVC was used to measure airway obstruction and reversibility of FEV1 was calculated. Current asthma was defined by self-reported doctor-diagnosis and evidence of currently active asthma. Symptom scores for asthma (CASS) and SDB were calculated. Intra-abdominal fat (IAF) was estimated using dual-energy x-ray absorptiometry (DXA). IR was calculated from fasting glucose and insulin concentrations. Results The prevalence of current doctor-diagnosed asthma was 19.9% (95% CI 16.7 – 23.5%). The ratio of observed to expected cases given the age and sex distribution of the population was 2.4 (95%CI 2.1, 2.9). IAF was not associated with current doctor-diagnosed asthma, FEV1/FVC or FEV1 reversibility in men or women but was positively associated with CASS independent of IR and SDB in women. A 1% increase in IAF was associated with decreases of 12 mL and 20 mL in FEV1 and FVC respectively in men, and 4 mL and 7 mL respectively in women. SDB mediated 12% and 26% of these associations respectively in men but had minimal effects in women. Conclusions In this population with an excess of doctor-diagnosed asthma, IAF was not a major factor in airway obstruction or doctor-diagnosed asthma, although women with higher IAF perceived more severe asthma symptoms which did not correlate with lower FEV1. Higher IAF was significantly associated with lower FEV1 and FVC and in men SDB mechanisms may

  12. Glucose screening tests during pregnancy

    MedlinePlus

    Oral glucose tolerance test - pregnancy; OGTT - pregnancy; Glucose challenge test - pregnancy; Gestational diabetes - glucose screening ... first step, you will have a glucose screening test: You DO NOT need to prepare or change ...

  13. Diesel exhaust particles and airway inflammation

    EPA Science Inventory

    Purpose of review. Epidemiologic investigation has associated traffic-related air pollution with adverse human health outcomes. The capacity ofdiesel exhaust particles (DEP), a major emission source air pollution particle, to initiate an airway inflammation has subsequently been ...

  14. Airway management for cervical spine surgery.

    PubMed

    Farag, Ehab

    2016-03-01

    Cervical spine surgery is one of the most commonly performed spine surgeries in the United States, and 90% of the cases are related to degenerative cervical spine disease (the rest to cervical spine trauma and/or instability). The airway management for cervical spine surgery represents a crucial step in the anesthetic management to avoid injury to the cervical cord. The crux for upper airway management for cervical spine surgery is maintaining the neck in a neutral position with minimal neck movement during endotracheal intubation. Therefore, the conventional direct laryngoscopy (DL) can be unsuitable for securing the upper airway in cervical spine surgery, especially in cases of cervical spine instability and myelopathy. This review discusses the most recent evidence-based facts of the main advantages and limitations of different techniques available for upper airway management for cervical spine surgery.

  15. Therapeutic bronchoscopic interventions for malignant airway obstruction

    PubMed Central

    Dalar, Levent; Özdemir, Cengiz; Abul, Yasin; Karasulu, Levent; Sökücü, Sinem Nedime; Akbaş, Ayşegül; Altın, Sedat

    2016-01-01

    Abstract There is no definitive consensus about the factors affecting the choice of interventional bronchoscopy in the management of malignant airway obstruction. The present study defines the choice of the interventional bronchoscopic modality and analyzes the factors influencing survival in patients with malignant central airway obstruction. Totally, over 7 years, 802 interventional rigid bronchoscopic procedures were applied in 547 patients having malignant airway obstruction. There was a significant association between the type of stent and the site of the lesion in the present study. Patients with tracheal involvement and/or involvement of the main bronchi had the worst prognosis. The sites of the lesion and endobronchial treatment modality were independent predictors of survival in the present study. The selection of different types of airway stents can be considered on the base of site of the lesion. Survival can be estimated based on the site of the lesion and endobronchial brochoscopic modality used. PMID:27281104

  16. Glucose determination with fiber optic spectrometers

    NASA Astrophysics Data System (ADS)

    Starke, Eva; Kemper, Ulf; Barschdorff, Dieter

    1999-05-01

    Noninvasive blood glucose monitoring is the aim of research activities concerning the detection of small glucose concentrations dissolved in water and blood plasma. One approach for these measurements is the exploitation of absorption bands in the near infrared. However, the strong absorption of water represents a major difficulty. Transmission measurements of glucose dissolved in water and in blood plasma in the spectral region around 1600 nm with one- beam spectrometers and a FT-IR spectrometer are discussed. The evaluation of the data is carried out using a two-layer Lambert-Beer model and neural networks. In order to reduce the dimensions of a potential measuring device, an integrated acousto-optic tunable filter (AOTF) with an Erbium doped fiber amplifier as a radiation source is used. The fiber optic components are examined concerning their suitability. The smallest concentrations of glucose dissolved in water that can be separated are approximately 50 mg/dl. In the range of 50 mg/dl to 1000 mg/dl a correlation coefficient of 0.98 between real and estimated glucose concentrations is achieved using neural networks. In blood plasma so far glucose concentrations of about 100 mg/dl can be distinguished with good accuracy.

  17. Taste Receptors in Upper Airway Immunity.

    PubMed

    Carey, Ryan M; Lee, Robert J; Cohen, Noam A

    2016-01-01

    Taste receptors are well known for their role in communicating information from the tongue to the brain about nutritional value or potential toxicity of ingested substances. More recently, it has been shown that taste receptors are expressed in other locations throughout the body, including the airway, gastrointestinal tract, brain and pancreas. The roles of some 'extraoral' taste receptors are largely unknown, but emerging research suggests that bitter and sweet taste receptors in the airway are capable of sensing bacteria and modulating innate immunity. This chapter focuses on the role of bitter and sweet taste receptors in human airway innate immunity and their clinical relevance to rhinosinusitis. The bitter taste receptor T2R38 expressed in sinonasal cilia detects bitter bacterial quorum-sensing molecules and activates a nitric oxide-dependent innate immune response; moreover, there are polymorphisms in T2R38 that underlie susceptibility to chronic rhinosinusitis (CRS). Bitter and sweet receptors in sinonasal solitary chemosensory cells control secretion of antimicrobial peptides in the upper airway and may have a profound impact on airway infections in patients with CRS and diabetes. Future research on taste receptors in the airway has enormous potential to expand our understanding of host-pathogen immune interactions and provide novel therapeutic targets.

  18. Sensory nerves in lung and airways.

    PubMed

    Lee, Lu-Yuan; Yu, Jerry

    2014-01-01

    Sensory nerves innervating the lung and airways play an important role in regulating various cardiopulmonary functions and maintaining homeostasis under both healthy and disease conditions. Their activities conducted by both vagal and sympathetic afferents are also responsible for eliciting important defense reflexes that protect the lung and body from potential health-hazardous effects of airborne particulates and chemical irritants. This article reviews the morphology, transduction properties, reflex functions, and respiratory sensations of these receptors, focusing primarily on recent findings derived from using new technologies such as neural immunochemistry, isolated airway-nerve preparation, cultured airway neurons, patch-clamp electrophysiology, transgenic mice, and other cellular and molecular approaches. Studies of the signal transduction of mechanosensitive afferents have revealed a new concept of sensory unit and cellular mechanism of activation, and identified additional types of sensory receptors in the lung. Chemosensitive properties of these lung afferents are further characterized by the expression of specific ligand-gated ion channels on nerve terminals, ganglion origin, and responses to the action of various inflammatory cells, mediators, and cytokines during acute and chronic airway inflammation and injuries. Increasing interest and extensive investigations have been focused on uncovering the mechanisms underlying hypersensitivity of these airway afferents, and their role in the manifestation of various symptoms under pathophysiological conditions. Several important and challenging questions regarding these sensory nerves are discussed. Searching for these answers will be a critical step in developing the translational research and effective treatments of airway diseases.

  19. Regulation of Airway Mucin Gene Expression

    PubMed Central

    Thai, Philip; Loukoianov, Artem; Wachi, Shinichiro; Wu, Reen

    2015-01-01

    Mucins are important components that exert a variety of functions in cell-cell interaction, epidermal growth factor receptor signaling, and airways protection. In the conducting airways of the lungs, mucins are the major contributor to the viscoelastic property of mucous secretion, which is the major barrier to trapping inhaled microbial organism, particulates, and oxidative pollutants. The homeostasis of mucin production is an important feature in conducting airways for the maintenance of mucociliary function. Aberrant mucin secretion and accumulation in airway lumen are clinical hallmarks associated with various lung diseases, such as asthma, chronic obstructive pulmonary disease, cystic fibrosis, emphysema, and lung cancer. Among 20 known mucin genes identified, 11 of them have been verified at either the mRNA and/or protein level in airways. The regulation of mucin genes is complicated, as are the mediators and signaling pathways. This review summarizes the current view on the mediators, the signaling pathways, and the transcriptional units that are involved in the regulation of airway mucin gene expression. In addition, we also point out essential features of epigenetic mechanisms for the regulation of these genes. PMID:17961085

  20. Nitrogen Dioxide Exposure and Airway Responsiveness in ...

    EPA Pesticide Factsheets

    Controlled human exposure studies evaluating the effect of inhaled NO2 on the inherent responsiveness of the airways to challenge by bronchoconstricting agents have had mixed results. In general, existing meta-analyses show statistically significant effects of NO2 on the airway responsiveness of individuals with asthma. However, no meta-analysis has provided a comprehensive assessment of clinical relevance of changes in airway responsiveness, the potential for methodological biases in the original papers, and the distribution of responses. This paper provides analyses showing that a statistically significant fraction, 70% of individuals with asthma exposed to NO2 at rest, experience increases in airway responsiveness following 30-minute exposures to NO2 in the range of 200 to 300 ppb and following 60-minute exposures to 100 ppb. The distribution of changes in airway responsiveness is log-normally distributed with a median change of 0.75 (provocative dose following NO2 divided by provocative dose following filtered air exposure) and geometric standard deviation of 1.88. About a quarter of the exposed individuals experience a clinically relevant reduction in their provocative dose due to NO2 relative to air exposure. The fraction experiencing an increase in responsiveness was statistically significant and robust to exclusion of individual studies. Results showed minimal change in airway responsiveness for individuals exposed to NO2 during exercise. A variety of fa

  1. Mechanical Properties of the Upper Airway

    PubMed Central

    Strohl, Kingman P.; Butler, James P.; Malhotra, Atul

    2013-01-01

    The importance of the upper airway (nose, pharynx, and larynx) in health and in the pathogenesis of sleep apnea, asthma, and other airway diseases, discussed elsewhere in the Comprehensive Physiology series, prompts this review of the biomechanical properties and functional aspects of the upper airway. There is a literature based on anatomic or structural descriptions in static circumstances, albeit studied in limited numbers of individuals in both health and disease. As for dynamic features, the literature is limited to studies of pressure and flow through all or parts of the upper airway and to the effects of muscle activation on such features; however, the links between structure and function through airway size, shape, and compliance remain a topic that is completely open for investigation, particularly through analyses using concepts of fluid and structural mechanics. Throughout are included both historically seminal references, as well as those serving as signposts or updated reviews. This article should be considered a resource for concepts needed for the application of biomechanical models of upper airway physiology, applicable to understanding the pathophysiology of disease and anticipated results of treatment interventions. PMID:23723026

  2. Slowly Adapting Sensory Units Have More Receptors in Large Airways than in Small Airways in Rabbits

    PubMed Central

    Liu, Jun; Song, Nana; Guardiola, Juan; Roman, Jesse; Yu, Jerry

    2016-01-01

    Sensory units of pulmonary slowly adapting receptors (SARs) are more active in large airways than in small airways. However, there is no explanation for this phenomenon. Although sensory structures in large airways resemble those in small airways, they are bigger and more complex. Possibly, a larger receptor provides greater surface area for depolarization, and thus has a lower activating threshold and/or a higher sensitivity to stretch, leading to more nerve electrical activities. Recently, a single sensory unit has been reported to contain multiple receptors. Therefore, sensory units in large airways may contain more SARs, which may contribute to high activities. To test this hypothesis, we used a double staining technique to identify sensory receptor sizes. We labeled the sensory structure with Na+/K+-ATPase antibodies and the myelin sheath with myelin basic protein (MBP) antibodies. A SAR can be defined as the end formation beyond MBP labeling. Thus, we are able to compare sizes of sensory structures and SARs in large (trachea and bronchi) vs. small (bronchioles <500 μm in diameter) airways in the rabbit. We found that even though the sensory structure was bigger in large airways than in small airways (3340 ± 223 vs. 1168 ± 103 μm2; P < 0.0001), there was no difference in receptor sizes (349 ± 14 vs. 326 ± 16 μm2; > 0.05). However, the sensory structure contains more SARs in large airways than in small airways (9.6 ± 0.6 vs. 3.6 ± 0.3; P < 0.0001). Thus, our data support the hypothesis that greater numbers of SARs in sensory units of large airways may contribute to higher activities. PMID:28018231

  3. Slowly Adapting Sensory Units Have More Receptors in Large Airways than in Small Airways in Rabbits.

    PubMed

    Liu, Jun; Song, Nana; Guardiola, Juan; Roman, Jesse; Yu, Jerry

    2016-01-01

    Sensory units of pulmonary slowly adapting receptors (SARs) are more active in large airways than in small airways. However, there is no explanation for this phenomenon. Although sensory structures in large airways resemble those in small airways, they are bigger and more complex. Possibly, a larger receptor provides greater surface area for depolarization, and thus has a lower activating threshold and/or a higher sensitivity to stretch, leading to more nerve electrical activities. Recently, a single sensory unit has been reported to contain multiple receptors. Therefore, sensory units in large airways may contain more SARs, which may contribute to high activities. To test this hypothesis, we used a double staining technique to identify sensory receptor sizes. We labeled the sensory structure with Na(+)/K(+)-ATPase antibodies and the myelin sheath with myelin basic protein (MBP) antibodies. A SAR can be defined as the end formation beyond MBP labeling. Thus, we are able to compare sizes of sensory structures and SARs in large (trachea and bronchi) vs. small (bronchioles <500 μm in diameter) airways in the rabbit. We found that even though the sensory structure was bigger in large airways than in small airways (3340 ± 223 vs. 1168 ± 103 μm(2); P < 0.0001), there was no difference in receptor sizes (349 ± 14 vs. 326 ± 16 μm(2); > 0.05). However, the sensory structure contains more SARs in large airways than in small airways (9.6 ± 0.6 vs. 3.6 ± 0.3; P < 0.0001). Thus, our data support the hypothesis that greater numbers of SARs in sensory units of large airways may contribute to higher activities.

  4. Multiphasic Absorption of Glucose and 3-O-Methyl Glucose by Aged Potato Slices 1

    PubMed Central

    Linask, Juri; Laties, George G.

    1973-01-01

    The isotherm for glucose absorption by aged potato (Solanum tuberosum var. Russet Burbank) discs shows four distinct phases in the concentration ranges 1.0 to 75 μm, 75 μm to 1.5 mm, 1.5 to 15 mm, and 15 to 100 mm, respectively. Each segment of the multiphasic isotherm, when plotted reciprocally by the method of Lineweaver and Burk or of Hofstee, without regard for uptake in earlier phases, indicates absorption rate to be a hyperbolic function of concentration. The observations suggest that glucose uptake is carrier-mediated, and that the transport barrier undergoes a series of all-or-none transformations at critical external concentrations, yielding successive new and higher values for the parameters Km and Vmax 3-O-Methyl glucose, a nonmetabolizable analogue of glucose, shows the same multiphasic absorption isotherm, with Km values essentially similar to those for glucose uptake, and Vmax values somewhat lower than those for glucose absorption. Whereas the first three phases of the absorption isotherm are taken to reflect passage across the plasma membrane, the fourth phase may reflect kinetics of glucose or 3-O-methyl glucose transport to the vacuole. PMID:16658317

  5. Toward a Continuous Intravascular Glucose Monitoring System

    PubMed Central

    Beier, Brooke; Musick, Katherine; Matsumoto, Akira; Panitch, Alyssa; Nauman, Eric; Irazoqui, Pedro

    2011-01-01

    Proof-of-concept studies that display the potential of using a glucose-sensitive hydrogel as a continuous glucose sensor are presented. The swelling ratio, porosity, and diffusivity of the hydrogel increased with glucose concentration. In glucose solutions of 50, 100, 200, and 300 mg/dL, the hydrogel swelling ratios were 4.9, 12.3, 15.9, and 21.7, respectively, and the swelling was reversible. The impedance across the hydrogel depended solely on the thickness and had an average increase of 47 Ω/mm. The hydrogels exposed to a hyperglycemic solution were more porous than the hydrogels exposed to a normal glycemic solution. The diffusivity of 390 Da MW fluorescein isothiocyanate in hydrogels exposed to normal and hyperglycemic solutions was examined using fluorescence recovery after photobleaching and was found to be 9.3 × 10−14 and 41.4 × 10−14 m2/s, respectively, compared to 6.2 × 10−10 m2/s in glucose solution. There was no significant difference between the permeability of hydrogels in normal and hyperglycemic glucose solutions with averages being 5.26 × 10−17 m2 and 5.80 × 10−17 m2, respectively, which resembles 2–4% agarose gels. A prototype design is presented for continuous intravascular glucose monitoring by attaching a glucose sensor to an FDA-approved stent. PMID:22344366

  6. Nebulized lidocaine blunts airway hyper-responsiveness in experimental feline asthma.

    PubMed

    Nafe, Laura A; Guntur, Vamsi P; Dodam, John R; Lee-Fowler, Tekla M; Cohn, Leah A; Reinero, Carol R

    2013-08-01

    Nebulized lidocaine may be a corticosteroid-sparing drug in human asthmatics, reducing airway resistance and peripheral blood eosinophilia. We hypothesized that inhaled lidocaine would be safe in healthy and experimentally asthmatic cats, diminishing airflow limitation and eosinophilic airway inflammation in the latter population. Healthy (n = 5) and experimentally asthmatic (n = 9) research cats were administered 2 weeks of nebulized lidocaine (2 mg/kg q8h) or placebo (saline) followed by a 2-week washout and crossover to the alternate treatment. Cats were anesthetized to measure the response to inhaled methacholine (MCh) after each treatment. Placebo and doubling doses of methacholine (0.0625-32.0000 mg/ml) were delivered and results were expressed as the concentration of MCh increasing baseline airway resistance by 200% (EC200Raw). Bronchoalveolar lavage was performed after each treatment and eosinophil numbers quantified. Bronchoalveolar lavage fluid (BALF) % eosinophils and EC200Raw within groups after each treatment were compared using a paired t-test (P <0.05 significant). No adverse effects were noted. In healthy cats, lidocaine did not significantly alter BALF eosinophilia or the EC200Raw. There was no difference in %BALF eosinophils in asthmatic cats treated with lidocaine (36±10%) or placebo (33 ± 6%). However, lidocaine increased the EC200Raw compared with placebo 10 ± 2 versus 5 ± 1 mg/ml; P = 0.043). Chronic nebulized lidocaine was well-tolerated in all cats, and lidocaine did not induce airway inflammation or airway hyper-responsiveness in healthy cats. Lidocaine decreased airway response to MCh in asthmatic cats without reducing airway eosinophilia, making it unsuitable for monotherapy. However, lidocaine may serve as a novel adjunctive therapy in feline asthmatics with beneficial effects on airflow obstruction.

  7. Lifestyle, glucose regulation and the cognitive effects of glucose load in middle-aged adults.

    PubMed

    Riby, Leigh M; McLaughlin, Jennifer; Riby, Deborah M; Graham, Cheryl

    2008-11-01

    Interventions aimed at improving glucose regulatory mechanisms have been suggested as a possible source of cognitive enhancement in the elderly. In particular, previous research has identified episodic memory as a target for facilitation after either moderate increases in glycaemia (after a glucose drink) or after improvements in glucose regulation. The present study aimed to extend this research by examining the joint effects of glucose ingestion and glucose regulation on cognition. In addition, risk factors associated with the development of poor glucose regulation in middle-aged adults were considered. In a repeated measures design, thirty-three middle-aged adults (aged 35-55 years) performed a battery of memory and non-memory tasks after either 25 g or 50 g glucose or a sweetness matched placebo drink. To assess the impact of individual differences in glucose regulation, blood glucose measurements were taken on four occasions during testing. A lifestyle and diet questionnaire was also administered. Consistent with previous research, episodic memory ability benefited from glucose ingestion when task demands were high. Blood glucose concentration was also found to predict performance across a number of cognitive domains. Interestingly, the risk factors associated with poor glucose regulation were linked to dietary impacts traditionally associated with poor health, e.g. the consumption of high-sugar sweets and drinks. The research replicates earlier work suggesting that task demands are critical to the glucose facilitation effect. Importantly, the data demonstrate clear associations between elevated glycaemia and relatively poor cognitive performance, which may be partly due to the effect of dietary and lifestyle factors.

  8. Exenatide Regulates Cerebral Glucose Metabolism in Brain Areas Associated With Glucose Homeostasis and Reward System.

    PubMed

    Daniele, Giuseppe; Iozzo, Patricia; Molina-Carrion, Marjorie; Lancaster, Jack; Ciociaro, Demetrio; Cersosimo, Eugenio; Tripathy, Devjit; Triplitt, Curtis; Fox, Peter; Musi, Nicolas; DeFronzo, Ralph; Gastaldelli, Amalia

    2015-10-01

    Glucagon-like peptide 1 receptors (GLP-1Rs) have been found in the brain, but whether GLP-1R agonists (GLP-1RAs) influence brain glucose metabolism is currently unknown. The study aim was to evaluate the effects of a single injection of the GLP-1RA exenatide on cerebral and peripheral glucose metabolism in response to a glucose load. In 15 male subjects with HbA1c of 5.7 ± 0.1%, fasting glucose of 114 ± 3 mg/dL, and 2-h glucose of 177 ± 11 mg/dL, exenatide (5 μg) or placebo was injected in double-blind, randomized fashion subcutaneously 30 min before an oral glucose tolerance test (OGTT). The cerebral glucose metabolic rate (CMRglu) was measured by positron emission tomography after an injection of [(18)F]2-fluoro-2-deoxy-d-glucose before the OGTT, and the rate of glucose absorption (RaO) and disposal was assessed using stable isotope tracers. Exenatide reduced RaO0-60 min (4.6 ± 1.4 vs. 13.1 ± 1.7 μmol/min ⋅ kg) and decreased the rise in mean glucose0-60 min (107 ± 6 vs. 138 ± 8 mg/dL) and insulin0-60 min (17.3 ± 3.1 vs. 24.7 ± 3.8 mU/L). Exenatide increased CMRglu in areas of the brain related to glucose homeostasis, appetite, and food reward, despite lower plasma insulin concentrations, but reduced glucose uptake in the hypothalamus. Decreased RaO0-60 min after exenatide was inversely correlated to CMRglu. In conclusion, these results demonstrate, for the first time in man, a major effect of a GLP-1RA on regulation of brain glucose metabolism in the absorptive state.

  9. Myo-inositol inhibits intestinal glucose absorption and promotes muscle glucose uptake: a dual approach study.

    PubMed

    Chukwuma, Chika Ifeanyi; Ibrahim, Mohammed Auwal; Islam, Md Shahidul

    2016-12-01

    The present study investigated the effects of myo-inositol on muscle glucose uptake and intestinal glucose absorption ex vivo as well as in normal and type 2 diabetes model of rats. In ex vivo study, both intestinal glucose absorption and muscle glucose uptake were studied in isolated rat jejunum and psoas muscle respectively in the presence of increasing concentrations (2.5 % to 20 %) of myo-inositol. In the in vivo study, the effect of a single bolus dose (1 g/kg bw) of oral myo-inositol on intestinal glucose absorption, blood glucose, gastric emptying and digesta transit was investigated in normal and type 2 diabetic rats after 1 h of co-administration with 2 g/kg bw glucose, when phenol red was used as a recovery marker. Myo-inositol inhibited intestinal glucose absorption (IC50 = 28.23 ± 6.01 %) and increased muscle glucose uptake, with (GU50 = 2.68 ± 0.75 %) or without (GU50 = 8.61 ± 0.55 %) insulin. Additionally, oral myo-inositol not only inhibited duodenal glucose absorption and reduced blood glucose increase, but also delayed gastric emptying and accelerated digesta transit in both normal and diabetic animals. Results of this study suggest that dietary myo-inositol inhibits intestinal glucose absorption both in ex vivo and in normal or diabetic rats and also promotes muscle glucose uptake in ex vivo condition. Hence, myo-inositol may be further investigated as a possible anti-hyperglycaemic dietary supplement for diabetic foods and food products.

  10. Self-powered glucose-responsive micropumps.

    PubMed

    Zhang, Hua; Duan, Wentao; Lu, Mengqian; Zhao, Xi; Shklyaev, Sergey; Liu, Lei; Huang, Tony Jun; Sen, Ayusman

    2014-08-26

    A self-powered polymeric micropump based on boronate chemistry is described. The pump is triggered by the presence of glucose in ambient conditions and induces convective fluid flows, with pumping velocity proportional to the glucose concentration. The pumping is due to buoyancy convection that originates from reaction-associated heat flux, as verified from experiments and finite difference modeling. As predicted, the fluid flow increases with increasing height of the chamber. In addition, pumping velocity is enhanced on replacing glucose with mannitol because of the enhanced exothermicity associated with the reaction of the latter.

  11. Evidence that humans can taste glucose polymers.

    PubMed

    Lapis, Trina J; Penner, Michael H; Lim, Juyun

    2014-11-01

    The sense of taste is essential for identifying potential nutrients and poisons. Accordingly, specialized taste receptor cells are activated by food-derived chemicals. Because of its importance in the human diet, oral detection of starch, or its degradation products, would presumably be highly beneficial. Yet, it has long been assumed that simple sugars are the only class of carbohydrates that humans can taste. There is, however, considerable evidence that rodents can taste starch degradation products (i.e., glucose polymers composed of maltooligosaccharides with 3-10 glucose units and maltopolysaccharides with >10 glucose units) and that their detection is independent of the sweet taste receptor, T1R2/T1R3. The present study was designed 1) to measure individual differences in human taste perception of glucose polymers, 2) to understand individual differences in the activity of salivary α-amylase, and 3) to investigate the role that salivary α-amylase may play in the taste perception of glucose polymers. In the first experiment, subjects rated taste intensity of glucose, sucrose, NaCl, and glucose polymers of various chain lengths, while their noses were clamped. Saliva samples from the subjects were also collected and their salivary α-amylase activity was assayed. Results showed that the perceived intensities of glucose, sucrose, and NaCl were significantly correlated (r = 0.75-0.85, P < 0.001), but not with the longer chain glucose polymers, whereas intensity ratings of all glucose polymers were highly correlated with one another (r = 0.69-0.82, P < 0.001). Importantly, despite large individual differences in α-amylase activity among subjects, responsiveness to glucose polymers did not significantly differ between individuals with high and low α-amylase activity. A follow up experiment was conducted to quantify the concentrations of glucose and maltose that were inherently present in the glucose polymer stimuli and to determine whether the amounts were

  12. PROINFLAMMATORY OXIDANT HYPOCHLOROUS ACID (HOCL) INDUCES DUAL SIGNALING PATHWAYS IN AIRWAY EPITHELIAL CELLS

    EPA Science Inventory

    In the airway of inflammatory diseases such as bacterial infection, cystic fibrosis and COPD, high level of HOCL (local concentration of up to 5mM) can be generated through a reaction catalyzed by leukocyte granule enzyme- Myeloperoxidase (MPO). HOCL is a very potent oxidative ag...

  13. Promotion of airway anastomotic microvascular regeneration and alleviation of airway ischemia by deferoxamine nanoparticles

    PubMed Central

    Tian, Wen; Sung, Yon K.; Sun, Wenchao; Hsu, Joe L.; Manickam, Sathish; Wagh, Dhananjay; Joubert, Lydia-Marie; Semenza, Gregg L.; Rajadas, Jayakumar; Nicolls, Mark R.

    2014-01-01

    Airway tissue ischemia and hypoxia in human lung transplantation is a consequence of the sacrifice of the bronchial circulation during the surgical procedure and is a major risk factor for the development of airway anastomotic complications. Augmented expression of hypoxia-inducible factor (HIF)-1α promotes microvascular repair and alleviates allograft ischemia and hypoxia. Deferoxamine mesylate (DFO) is an FDA-approved iron chelator which has been shown to upregulate cellular HIF-1α. Here, we developed a nanoparticle formulation of DFO that can be topically applied to airway transplants at the time of surgery. In a mouse orthotopic tracheal transplant (OTT) model, the DFO nanoparticle was highly effective in enhancing airway microvascular perfusion following transplantation through the production of the angiogenic factors, placental growth factor (PLGF) and stromal cell-derived factor (SDF)-1. The endothelial cells in DFO treated airways displayed higher levels of p-eNOS and Ki67, less apoptosis, and decreased production of perivascular reactive oxygen species (ROS) compared to vehicle-treated airways. In summary, a DFO formulation topically-applied at the time of surgery successfully augmented airway anastomotic microvascular regeneration and the repair of alloimmune-injured microvasculature. This approach may be an effective topical transplant-conditioning therapy for preventing airway complications following clinical lung transplantation. PMID:24161166

  14. Airway smooth muscle in airway reactivity and remodeling: what have we learned?

    PubMed Central

    2013-01-01

    It is now established that airway smooth muscle (ASM) has roles in determining airway structure and function, well beyond that as the major contractile element. Indeed, changes in ASM function are central to the manifestation of allergic, inflammatory, and fibrotic airway diseases in both children and adults, as well as to airway responses to local and environmental exposures. Emerging evidence points to novel signaling mechanisms within ASM cells of different species that serve to control diverse features, including 1) [Ca2+]i contractility and relaxation, 2) cell proliferation and apoptosis, 3) production and modulation of extracellular components, and 4) release of pro- vs. anti-inflammatory mediators and factors that regulate immunity as well as the function of other airway cell types, such as epithelium, fibroblasts, and nerves. These diverse effects of ASM “activity” result in modulation of bronchoconstriction vs. bronchodilation relevant to airway hyperresponsiveness, airway thickening, and fibrosis that influence compliance. This perspective highlights recent discoveries that reveal the central role of ASM in this regard and helps set the stage for future research toward understanding the pathways regulating ASM and, in turn, the influence of ASM on airway structure and function. Such exploration is key to development of novel therapeutic strategies that influence the pathophysiology of diseases such as asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis. PMID:24142517

  15. Two-dimensional airway analysis using probabilistic neural networks

    NASA Astrophysics Data System (ADS)

    Tan, Jun; Zheng, Bin; Park, Sang Cheol; Pu, Jiantao; Sciurba, Frank C.; Leader, Joseph K.

    2010-03-01

    Although 3-D airway tree segmentation permits analysis of airway tree paths of practical lengths and facilitates visual inspection, our group developed and tested an automated computer scheme that was operated on individual 2-D CT images to detect airway sections and measure their morphometry and/or dimensions. The algorithm computes a set of airway features including airway lumen area (Ai), airway cross-sectional area (Aw), the ratio (Ra) of Ai to Aw, and the airway wall thickness (Tw) for each detected airway section depicted on the CT image slice. Thus, this 2-D based algorithm does not depend on the accuracy of 3-D airway tree segmentation and does not require that CT examination encompasses the entire lung or reconstructs contiguous images. However, one disadvantage of the 2-D image based schemes is the lack of the ability to identify the airway generation (Gb) of the detected airway section. In this study, we developed and tested a new approach that uses 2-D airway features to assign a generation number to an airway. We developed and tested two probabilistic neural networks (PNN) based on different sets of airway features computed by our 2-D based scheme. The PNNs were trained and tested on 12 lung CT examinations (8 training and 4 testing). The accuracy for the PNN that utilized Ai and Ra for identifying the generation of airway sections varies from 55.4% - 100%. The overall accuracy of the PNN for all detected airway sections that are spread over all generations is 76.7%. Interestingly, adding wall thickness feature (Tw) to PNN did not improve identification accuracy. This preliminary study demonstrates that a set of 2-D airway features may be used to identify the generation number of an airway with reasonable accuracy.

  16. The relation of airway size to lung function

    NASA Astrophysics Data System (ADS)

    Leader, J. Ken; Zheng, Bin; Sciurba, Frank C.; Fuhrman, Carl R.; Bon, Jessica M.; Park, Sang C.; Pu, Jiantao; Gur, David

    2008-03-01

    Chronic obstructive pulmonary disease may cause airway remodeling, and small airways are the mostly likely site of associated airway flow obstruction. Detecting and quantifying airways depicted on a typical computed tomography (CT) images is limited by spatial resolution. In this study, we examined the association between lung function and airway size. CT examinations and spirometry measurement of forced expiratory volume in one second as a percent predicted (FEV I%) from 240 subjects were used in this study. Airway sections depicted in axial CT section were automatically detected and quantified. Pearson correlation coefficients (PCC) were computed to compare lung function across three size categories: (1) all detected airways, (2) the smallest 50% of detected airways, and (3) the largest 50% of detected airways using the CORANOVA test. The mean number of all airways detected per subject was 117.4 (+/- 40.1) with mean size ranging from 20.2 to 50.0 mm2. The correlation between lung function (i.e., FEV I) and airway morphometry associated with airway remodeling and airflow obstruction (i.e., lumen perimeter and wall area as a percent of total airway area) was significantly stronger for smaller compared to larger airways (p < 0.05). The PCCs between FEV I and all airways, the smallest 50%, and the largest 50% were 0.583, 0.617, 0.523, respectively, for lumen perimeter and -0.560, -0.584, and -0.514, respectively, for wall area percent. In conclusion, analyzing a set of smaller airways compared to larger airways may improve detection of an association between lung function and airway morphology change.

  17. Sensing of glucose in the gastrointestinal tract.

    PubMed

    Raybould, Helen E

    2007-04-30

    In general, nutrient sensing mechanisms in the intestine are not well understood. Potential sensors include the terminals of extrinsic afferent nerves, enteric nerves, endocrine cells and other epithelial cells including enterocytes and immune cells. This short review will concentrate on the neural pathways that are activated by the presence of glucose in the intestinal lumen and the role of a specialized endocrine cell, the enterochromaffin cell in glucose-sensing and the subsequent activation of extrinsic neural pathways.

  18. I-gel Laryngeal Mask Airway Combined with Tracheal Intubation Attenuate Systemic Stress Response in Patients Undergoing Posterior Fossa Surgery

    PubMed Central

    Tang, Chaoliang; Chai, Xiaoqing; Kang, Fang; Huang, Xiang; Hou, Tao; Tang, Fei; Li, Juan

    2015-01-01

    Background. The adverse events induced by intubation and extubation may cause intracranial hemorrhage and increase of intracranial pressure, especially in posterior fossa surgery patients. In this study, we proposed that I-gel combined with tracheal intubation could reduce the stress response of posterior fossa surgery patients. Methods. Sixty-six posterior fossa surgery patients were randomly allocated to receive either tracheal tube intubation (Group TT) or I-gel facilitated endotracheal tube intubation (Group TI). Hemodynamic and respiratory variables, stress and inflammatory response, oxidative stress, anesthesia recovery parameters, and adverse events during emergence were compared. Results. Mean arterial pressure and heart rate were lower in Group TI during intubation and extubation (P < 0.05 versus Group TT). Respiratory variables including peak airway pressure and end-tidal carbon dioxide tension were similar intraoperative, while plasma β-endorphin, cortisol, interleukin-6, tumor necrosis factor-alpha, malondialdehyde concentrations, and blood glucose were significantly lower in Group TI during emergence relative to Group TT. Postoperative bucking and serious hypertensions were seen in Group TT but not in Group TI. Conclusion. Utilization of I-gel combined with endotracheal tube in posterior fossa surgery patients is safe which can yield more stable hemodynamic profile during intubation and emergence and lower inflammatory and oxidative response, leading to uneventful recovery. PMID:26273146

  19. Glucose metabolism in pregnant sheep when placental growth is restricted

    SciTech Connect

    Owens, J.A.; Falconer, J.; Robinson, J.S. )

    1989-08-01

    The effect of restricting placental growth on glucose metabolism in pregnant sheep in late gestation was determined by primed constant infusions of D-(U-{sup 14}C)- and D-(2-{sup 3}H)glucose and antipyrine into fetuses of six control sheep and six sheep from which endometrial caruncles had been removed before pregnancy (caruncle sheep). In the latter, placental and fetal weights were reduced, as was the concentration of glucose in fetal arterial blood. Fetal glucose turnover in caruncle sheep was only 52-59% of that in controls, largely because of lower umbilical loss of glucose back to the placenta (38-39% of control) and lower fetal glucose utilization (61-74% of control). However, fetal glucose utilization on a weight-specific basis was similar in control and caruncle sheep. Significant endogenous glucose production occurred in control and caruncle fetal sheep. Maternal glucose production and partition of glucose between the gravid uterus and other maternal tissues were similar in control and caruncle sheep. In conclusion, when placental and fetal growth are restricted, fetal glucose utilization is maintained by reduced loss of glucose back to the placenta and mother and by maintaining endogenous glucose production.

  20. Insulin Signaling in the Control of Glucose and Lipid Homeostasis.

    PubMed

    Saltiel, Alan R

    2016-01-01

    A continuous supply of glucose is necessary to ensure proper function and survival of all organs. Plasma glucose levels are thus maintained in a narrow range around 5 mM, which is considered the physiological set point. Glucose homeostasis is controlled primarily by the liver, fat, and skeletal muscle. Following a meal, most glucose disposals occur in the skeletal muscle, whereas fasting plasma glucose levels are determined primarily by glucose output from the liver. The balance between the utilization and production of glucose is primarily maintained at equilibrium by two opposing hormones, insulin and glucagon. In response to an elevation in plasma glucose and amino acids (after consumption of a meal), insulin is released from the beta cells of the islets of Langerhans in the pancreas. When plasma glucose falls (during fasting or exercise), glucagon is secreted by α cells, which surround the beta cells in the pancreas. Both cell types are extremely sensitive to glucose concentrations, can regulate hormone synthesis, and are released in response to small changes in plasma glucose levels. At the same time, insulin serves as the major physiological anabolic agent, promoting the synthesis and storage of glucose, lipids, and proteins and inhibiting their degradation and release back into the circulation. This chapter will focus mainly on signal transduction mechanisms by which insulin exerts its plethora of effects in liver, muscle, and fat cells, focusing on those pathways that are crucial in the control of glucose and lipid homeostasis.

  1. Airway pressure with chest compressions versus Heimlich manoeuvre in recently dead adults with complete airway obstruction.

    PubMed

    Langhelle, A; Sunde, K; Wik, L; Steen, P A

    2000-04-01

    In a previous case report a standard chest compression successfully removed a foreign body from the airway after the Heimlich manoeuvre had failed. Based on this case, standard chest compressions and Heimlich manoeuvres were performed by emergency physicians o