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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. Increased airway glucose increases airway bacterial load in hyperglycaemia.

    PubMed

    Gill, Simren K; Hui, Kailyn; Farne, Hugo; Garnett, James P; Baines, Deborah L; Moore, Luke S P; Holmes, Alison H; Filloux, Alain; Tregoning, John S

    2016-01-01

    Diabetes is associated with increased frequency of hospitalization due to bacterial lung infection. We hypothesize that increased airway glucose caused by hyperglycaemia leads to increased bacterial loads. In critical care patients, we observed that respiratory tract bacterial colonisation is significantly more likely when blood glucose is high. We engineered mutants in genes affecting glucose uptake and metabolism (oprB, gltK, gtrS and glk) in Pseudomonas aeruginosa, strain PAO1. These mutants displayed attenuated growth in minimal medium supplemented with glucose as the sole carbon source. The effect of glucose on growth in vivo was tested using streptozocin-induced, hyperglycaemic mice, which have significantly greater airway glucose. Bacterial burden in hyperglycaemic animals was greater than control animals when infected with wild type but not mutant PAO1. Metformin pre-treatment of hyperglycaemic animals reduced both airway glucose and bacterial load. These data support airway glucose as a critical determinant of increased bacterial load during diabetes. PMID:27273266

  3. Increased airway glucose increases airway bacterial load in hyperglycaemia

    PubMed Central

    Gill, Simren K.; Hui, Kailyn; Farne, Hugo; Garnett, James P.; Baines, Deborah L.; Moore, Luke S.P.; Holmes, Alison H.; Filloux, Alain; Tregoning, John S.

    2016-01-01

    Diabetes is associated with increased frequency of hospitalization due to bacterial lung infection. We hypothesize that increased airway glucose caused by hyperglycaemia leads to increased bacterial loads. In critical care patients, we observed that respiratory tract bacterial colonisation is significantly more likely when blood glucose is high. We engineered mutants in genes affecting glucose uptake and metabolism (oprB, gltK, gtrS and glk) in Pseudomonas aeruginosa, strain PAO1. These mutants displayed attenuated growth in minimal medium supplemented with glucose as the sole carbon source. The effect of glucose on growth in vivo was tested using streptozocin-induced, hyperglycaemic mice, which have significantly greater airway glucose. Bacterial burden in hyperglycaemic animals was greater than control animals when infected with wild type but not mutant PAO1. Metformin pre-treatment of hyperglycaemic animals reduced both airway glucose and bacterial load. These data support airway glucose as a critical determinant of increased bacterial load during diabetes. PMID:27273266

  4. Optical monitoring of glucose concentration

    NASA Astrophysics Data System (ADS)

    Ross, I. N.; Mbanu, A.

    1985-02-01

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

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

    PubMed

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

    2016-01-01

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

  6. Blood glucose concentration in pediatric outpatient surgery.

    PubMed

    Somboonviboon, W; Kijmahatrakul, W

    1996-04-01

    Blood glucose concentration was measured in 84 pediatric patients who were scheduled for outpatient surgery at Chulalongkorn Hospital. They were allocated into 3 groups according to their ages, group 1:less than 1 year of age, group 2:1 to 5 years of age and group 3:over 5 years. The fasting times were approximately 8-12 hours. All patients received standard general anesthesia under mask. No glucose solution was given during operation. Preoperative mean blood glucose were 91.09 +/- 17.34, 89.55 +/- 18.69 and 82.14 +/- 16.14 mg/dl in group 1, 2 and 3 while the postoperative mean glucose values were 129.07 +/- 37.90, 115.62 +/- 29.63 and 111.53 +/- 23.07 mg/dl respectively. The difference between pre- and post-operative values were statistically significant difference (P < 0.01). None of the children had hypoglycemia even when fasting longer than expected. Increased postoperative glucose values may be due to stress response from surgery and anesthesia. We would suggest that the parents give the fluid to their children according to our instructions in order to prevent dehydration and hypoglycemia especially in small infants.

  7. Fructose transport-deficient Staphylococcus aureus reveals important role of epithelial glucose transporters in limiting sugar-driven bacterial growth in airway surface liquid.

    PubMed

    Garnett, James P; Braun, Daniela; McCarthy, Alex J; Farrant, Matthew R; Baker, Emma H; Lindsay, Jodi A; Baines, Deborah L

    2014-12-01

    Hyperglycaemia as a result of diabetes mellitus or acute illness is associated with increased susceptibility to respiratory infection with Staphylococcus aureus. Hyperglycaemia increases the concentration of glucose in airway surface liquid (ASL) and promotes the growth of S. aureus in vitro and in vivo. Whether elevation of other sugars in the blood, such as fructose, also results in increased concentrations in ASL is unknown and whether sugars in ASL are directly utilised by S. aureus for growth has not been investigated. We obtained mutant S. aureus JE2 strains with transposon disrupted sugar transport genes. NE768(fruA) exhibited restricted growth in 10 mM fructose. In H441 airway epithelial-bacterial co-culture, elevation of basolateral sugar concentration (5-20 mM) increased the apical growth of JE2. However, sugar-induced growth of NE768(fruA) was significantly less when basolateral fructose rather than glucose was elevated. This is the first experimental evidence to show that S. aureus directly utilises sugars present in the ASL for growth. Interestingly, JE2 growth was promoted less by glucose than fructose. Net transepithelial flux of D-glucose was lower than D-fructose. However, uptake of D-glucose was higher than D-fructose across both apical and basolateral membranes consistent with the presence of GLUT1/10 in the airway epithelium. Therefore, we propose that the preferential uptake of glucose (compared to fructose) limits its accumulation in ASL. Pre-treatment with metformin increased transepithelial resistance and reduced the sugar-dependent growth of S. aureus. Thus, epithelial paracellular permeability and glucose transport mechanisms are vital to maintain low glucose concentration in ASL and limit bacterial nutrient sources as a defence against infection.

  8. 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.

  9. 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

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

    PubMed

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

    1982-01-01

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

  11. Concentration effect on the diffusion of glucose in ocular tissues

    NASA Astrophysics Data System (ADS)

    Ghosn, Mohamad G.; Carbajal, Esteban F.; Befrui, Natasha A.; Tuchin, Valery V.; Larin, Kirill V.

    2008-12-01

    In this study, optical coherence tomography (OCT) was utilized in the functional imaging of glucose diffusion through scleral tissues. Permeability coefficients for different concentrations of glucose were quantified nondestructively. Obtained results indicate an inverse proportionality between the permeability coefficient and the concentration of the analyte in epithelial tissues: in-depth diffusion of solutions with lower glucose concentration was faster than those with a higher concentration. The permeability coefficient decreased from (1.67±0.17)×10 -5 cm/s of 10% glucose solution to (5.08±0.23)×10 -6 cm/s of 25% glucose solution. The dependence of the permeability on the concentration of hyperosmotic analytes could potentially be used in various basic science and clinical fields, such as optical clearing of tissues and cells as well as in clinical pharmacology.

  12. 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.

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

    PubMed

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

    2007-02-01

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

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

    PubMed Central

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

    2007-01-01

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

  15. 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.

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

    PubMed Central

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

    2015-01-01

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

  17. Role for the pineal and melatonin in glucose homeostasis: pinealectomy increases night-time glucose concentrations.

    PubMed

    la Fleur, S E; Kalsbeek, A; Wortel, J; van der Vliet, J; Buijs, R M

    2001-12-01

    The effects of melatonin on glucose metabolism are far from understood. In rats, the biological clock generates a 24-h rhythm in plasma glucose concentrations, with declining concentrations in the dark period. We hypothesized that, in the rat, melatonin enhances the dark signal of the biological clock, decreasing glucose concentrations in the dark period. We measured 24-h rhythms of plasma concentrations of glucose and insulin in pinealectomized rats fed ad libitum and subjected to a scheduled feeding regimen with six meals equally distributed over the light/dark cycle and compared them with previous data of intact rats. Pinealectomy dampened the amplitude of the 24-h rhythm in plasma glucose concentrations in rats fed ad libitum, and abolished it completely in rats subjected to the scheduled feeding regimen, while plasma insulin concentrations did not change under both conditions. Pinealectomy abolished the nocturnal decline in plasma glucose concentrations irrespective of whether rats were fed ad libitum or subjected to the scheduled feeding regimen. Melatonin replacement restored 24-h mean plasma glucose concentrations in pinealectomized rats that were subjected to the scheduled feeding regimen but, interestingly, it did not restore the 24-h rhythm. Melatonin treatment also resulted in higher meal-induced insulin responses, probably mediated via an increased sensitivity of the beta-cells. Taken together, our data demonstrate that the pineal hormone, melatonin, influences both glucose metabolism and insulin secretion from the pancreatic beta-cell. The present study also demonstrates that removal of the pineal gland cannot be compensated by mimicking plasma melatonin concentrations only.

  18. Diagnosis of prediabetes in cats: glucose concentration cut points for impaired fasting glucose and impaired glucose tolerance.

    PubMed

    Reeve-Johnson, M K; Rand, J S; Vankan, D; Anderson, S T; Marshall, R; Morton, J M

    2016-10-01

    Diabetes is typically diagnosed in cats once clinical signs are evident. Diagnostic criteria for prediabetes in cats have not been defined. The objective of the study was to establish methodology and cut points for fasting and 2-h blood glucose concentrations in healthy client-owned senior cats (≥8 yr) using ear/paw samples and a portable glucose meter calibrated for feline blood. Of the 78 cats, 27 were ideal (body condition score [BCS] 4 or 5 of 9), 31 overweight (BCS 6 or 7), and 20 obese (BCS 8 or 9); 19 were Burmese and 59 non-Burmese. After an 18-24-h fast and an ear/paw blood glucose measurement using a portable glucose meter, glucose (0.5 g/kg bodyweight) was administered intravenous and blood glucose measured at 2 min and 2 h. Cut points for fasting and 2-h glucose concentrations were defined as the upper limits of 95% reference intervals using cats with BCS 4 or 5. The upper cut point for fasting glucose was 6.5 mmol/L. Of the overweight and obese cats, 1 (BCS 7) was above this cut point indicating evidence of impaired fasting glucose. The cut point for 2-h glucose was 9.8 mmol/L. A total of 7 cats (4 with BCS 8 or 9 including 1 Burmese; 3 with BCS 6 or 7, non-Burmese) were above this cut point and thus had evidence of impaired glucose tolerance. In conclusion, the methodology and cutpoints for diagnosis of prediabetes are defined for use in healthy cats 8 yr and older with a range of BCSs. PMID:27565231

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

    PubMed

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

    2015-12-10

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2008-10-23

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

  3. 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.

  4. 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

  5. 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

  6. SLEEP/WAKE DEPENDENT CHANGES IN CORTICAL GLUCOSE CONCENTRATIONS

    PubMed Central

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

    2012-01-01

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

  7. 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.

  8. 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.

  9. 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.

  10. Direct measurement of brain glucose concentrations in humans by sup 13 C NMR spectroscopy

    SciTech Connect

    Gruetter, R.; Novotny, E.J.; Boulware, S.D.; Rothman, D.L.; Mason, G.F.; Shulman, G.I.; Shulan, R.G.; Tamborlane, W.V. )

    1992-02-01

    Glucose is the main fuel for energy metabolism in the normal human brain. It is generally assumed that glucose transport into the brain is not rate-limiting for metabolism. Since brain glucose concentrations cannot be determined directly by radiotracer techniques, the authors used {sup 13}C NMR spectroscopy after infusing enriched D-(1-{sup 13}C)glucose to measure brain glucose concentrations at euglycemia and at hyperglycemia in six healthy children. Brain glucose concentrations averaged 1.0 {plus minus} 0.1 {mu}mol/ml at euglycemia and 1.8-2.7 {mu}mol/ml at hyperglycemia. Michaelis-Menten parameters of transport were calculated from the relationship between plasma and brain glucose concentrations. The brain glucose concentrations and transport constants are consistent with transport not being rate-limiting for resting brain metabolism at plasma levels >3 mM.

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

    NASA Astrophysics Data System (ADS)

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

    2001-10-01

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

  12. 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.

  13. Effects of elevated glucose concentration on cultured bovine retinal endothelial (BRE) cells

    SciTech Connect

    Capetandes, A.; Gerritsen, M.E.

    1986-03-01

    Salient clinical features of diabetic retinopathy include capillary microaneurysm and neovascularization, which progress with the severity of the disease. It has been suggested that exposure of the retinal vascular cells to high glucose concentrations may play a causative role in the retinopathy. In the present study, the effects of variant media glucose concentrations on BRE cell growth were determined. Normal growth curves were obtained with glucose concentrations of 100, 450 and 600 mg%, but the replication rate was decreased with 600 mg%. To determine if elevated glucose concentrations also altered DNA synthesis, BRE cells cultivated with 100 and 600 mg% glucose demonstrated increased thymidine uptake and total DNA content compared to the 100 mg% group. Furthermore, vacuolation and increased cell diameter occurred in BRE cells cultivated 600 mg% compared to 100 mg% glucose. In conclusion, increases in media glucose concentrations result in a decreased cellular replication rate, increased DNA synthesis and increased cell diameter during the log phase of growth.

  14. Comparison of blood glucose concentrations after administration of a glucose solution via the jugular vein and portal vein in cows.

    PubMed

    Braun, U; Heusmann, B; Camenzind, D; Haessig, M

    2007-10-01

    The goals of the present study were to determine whether the infusion of a glucose solution into the portal vein is tolerated in cows and whether the glucose concentration differs after administration of glucose into the jugular vein and portal vein. Fifteen healthy Swiss Braunvieh cows were used. An indwelling catheter was placed in both jugular veins and a balloon-tipped indwelling catheter with a diameter of 2 mm was placed in the portal vein under the guidance of ultrasonography. Three cows received 500 ml of 20% glucose solution over 60 min via the left jugular vein. Three other cows received the same solution over 60 min via the portal vein. Blood samples were collected from the right jugular vein before and for 24 h after the infusion of glucose for the determination of the concentrations of glucose and bilirubin and the activities of glutamate dehydrogenase, sorbitol dehydrogenase and gamma-glutamyl transferase. Infusion via the portal vein did not result in abnormalities in the general condition of the cows or increases in the concentration of bilirubin or the activities of liver enzymes. The blood glucose concentration increased to the same extent after both intraportal and intrajugular infusion. Over a 12-h period, three cows received 10 l of 20% glucose solution via the left jugular vein and three others received the same solution over a 12-h period via the portal vein. Blood samples were collected from the right jugular vein before and for 30 h after the start of infusion. Infusion via the portal vein did not affect the general condition of the cows or the activities of the liver enzymes. There was no significant difference in the blood glucose concentration between the two groups throughout the study.

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

    NASA Astrophysics Data System (ADS)

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

    2002-07-01

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

  16. 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...

  17. Glucose and glycerol concentrations and their tracer enrichment measurements using liquid chromatography tandem mass spectrometry.

    PubMed

    Bornø, Andreas; Foged, Lene; van Hall, Gerrit

    2014-10-01

    The present study describes a new liquid chromatography tandem mass spectrometry method for high-throughput quantification of glucose and glycerol in human plasma using stable isotopically labeled internal standards and is suitable for simultaneous measurements of glucose and glycerol enrichments in connection to in vivo metabolic studies investigating glucose turnover and lipolytic rate. Moreover, in order to keep up with this new fast analysis, simple derivatization procedures have been developed. Prior to analysis, glucose and glycerol were derivatized using benzoyl chloride in order to form benzoylated derivatives via new simplified fast procedures. For glucose, two internal standards were evaluated, [U-(13) C(6)]glucose and [U-(13) C(6), D(7)]glucose, and for glycerol, [U-(13) C(3), D(8)]glycerol was used. The method was validated by means of calibration curves, quality control samples, and plasma samples spiked with [6,6-D(2)]glucose, [U-(13) C(6)]glucose, and [1,1,2,3,3-D(5)]glycerol in order to test accuracy, precision, and recovery of the method. Moreover, post preparative and freeze-thaw sample stability were tested. The correlation of calibration curves for the glucose concentration were r(2) = 0.9998 for [U-(13) C(6)]glucose and r(2) = 0.9996 for [U-(13) C(6), D(7)]glucose, and r(2) = 0.9995 for the glycerol concentration. Interday accuracy for glucose using [U-(13) C(6)]glucose and glycerol determined in spiked plasma were respectively 103.5% and 106.0%, and the coefficients of variation were 2.0% and 9.7%, respectively. After derivatization, plasma samples were stable for at least 14 days. In conclusion, we have developed and validated a novel, accurate, and sensitive high-throughput liquid chromatography tandem mass spectrometry method for simultaneous determination of glucose and glycerol concentrations and enrichment of infused tracers most commonly used in human metabolic kinetic studies.

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

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen

    2015-08-01

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

  19. 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.

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

    PubMed

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

    1991-04-01

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

  1. [Effect of glucose concentration on the biosynthesis of prodigiosin by serratia marcescens (author's transl)].

    PubMed

    Lorén, J G; Guinea, J

    1978-09-01

    Serratia marcescens is an enterobacteria which produces a characteristic red pigment denominated prodigiosin. To study the effect of glucose on the kinetics of this secondary metabolite, cultures of Serratia marcescens S10 were incubated at 30 degrees C in the mineral medium GL, with glucose (2 g/l) as the carbon source. Prodigiosin production in relation to glucose consumption is studied, and parallel-wise, the effect of various concentrations of glucose on prodigiosin production. The kinetics data show the close correlation between glucose consumption and the synthesis of prodigiosin. This substrate inhibits the synthesis of pigment in cultures grown on solid medium GL with concentrations of glucose up to 15 g/l.

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

    PubMed Central

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

    1991-01-01

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

  3. Effects of reduced mucus oxygen concentration in airway Pseudomonas infections of cystic fibrosis patients

    PubMed Central

    Worlitzsch, Dieter; Tarran, Robert; Ulrich, Martina; Schwab, Ute; Cekici, Aynur; Meyer, Keith C.; Birrer, Peter; Bellon, Gabriel; Berger, Jürgen; Weiss, Tilo; Botzenhart, Konrad; Yankaskas, James R.; Randell, Scott; Boucher, Richard C.; Döring, Gerd

    2002-01-01

    Current theories of CF pathogenesis predict different predisposing “local environmental” conditions and sites of bacterial infection within CF airways. Here we show that, in CF patients with established lung disease, Psuedomonas aeruginosa was located within hypoxic mucopurulent masses in airway lumens. In vitro studies revealed that CF-specific increases in epithelial O2 consumption, linked to increased airway surface liquid (ASL) volume absorption and mucus stasis, generated steep hypoxic gradients within thickened mucus on CF epithelial surfaces prior to infection. Motile P. aeruginosa deposited on CF airway surfaces penetrated into hypoxic mucus zones and responded to this environment with increased alginate production. With P. aeruginosa growth in oxygen restricted environments, local hypoxia was exacerbated and frank anaerobiosis, as detected in vivo, resulted. These studies indicate that novel therapies for CF include removal of hypoxic mucus plaques and antibiotics effective against P. aeruginosa adapted to anaerobic environments. PMID:11827991

  4. Transcriptional analysis of adaptation to high glucose concentrations in Zymomonas mobilis.

    PubMed

    Zhang, Kun; Shao, Huanhuan; Cao, Qinghua; He, Ming-Xiong; Wu, Bo; Feng, Hong

    2015-02-01

    The ethanologenic bacterium Zymomonas mobilis is usually tolerant to high concentrations of glucose. The addition of sorbitol decreases the lag phase and increases ethanol yield and productivity of the bacteria in high glucose concentrations. The molecular mechanisms of adaptation to high glucose concentrations and the effect of sorbitol are still unclear. In this study, microarray analysis was used to study the global transcriptional adaptation responses of Z. mobilis to high glucose concentrations. A total of 235 genes were differentially expressed when 220 g/L glucose was added with or without 10 mM sorbitol. These genes are involved in diverse aspects of cell metabolism and regulation, including membrane transporters, nitrogen metabolism, and plasmid-encoded genes. However, most differentially expressed genes were downregulated when sorbitol was added. Notably, the transcription of almost all genes involved in the Entner-Doudoroff and ethanol production pathways was not significantly affected. In addition, a prophage and a nitrogen-fixation cluster were significantly induced. These results revealed that Z. mobilis cells responded to high glucose concentrations by regulating the transcriptional levels of genes related to membrane channels and transporters, stress response mechanisms, and metabolic pathways. These data provide insight into the intracellular adaptation responses to high glucose concentrations and reveal strategies to engineer efficient ethanol fermentation in Z. mobilis.

  5. Transcriptional analysis of adaptation to high glucose concentrations in Zymomonas mobilis.

    PubMed

    Zhang, Kun; Shao, Huanhuan; Cao, Qinghua; He, Ming-Xiong; Wu, Bo; Feng, Hong

    2015-02-01

    The ethanologenic bacterium Zymomonas mobilis is usually tolerant to high concentrations of glucose. The addition of sorbitol decreases the lag phase and increases ethanol yield and productivity of the bacteria in high glucose concentrations. The molecular mechanisms of adaptation to high glucose concentrations and the effect of sorbitol are still unclear. In this study, microarray analysis was used to study the global transcriptional adaptation responses of Z. mobilis to high glucose concentrations. A total of 235 genes were differentially expressed when 220 g/L glucose was added with or without 10 mM sorbitol. These genes are involved in diverse aspects of cell metabolism and regulation, including membrane transporters, nitrogen metabolism, and plasmid-encoded genes. However, most differentially expressed genes were downregulated when sorbitol was added. Notably, the transcription of almost all genes involved in the Entner-Doudoroff and ethanol production pathways was not significantly affected. In addition, a prophage and a nitrogen-fixation cluster were significantly induced. These results revealed that Z. mobilis cells responded to high glucose concentrations by regulating the transcriptional levels of genes related to membrane channels and transporters, stress response mechanisms, and metabolic pathways. These data provide insight into the intracellular adaptation responses to high glucose concentrations and reveal strategies to engineer efficient ethanol fermentation in Z. mobilis. PMID:25582559

  6. 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

  7. 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

  8. Influence of glucose concentration on the membrane stability of human erythrocytes.

    PubMed

    Lemos, Guilherme Santos Duarte; Márquez-Bernardes, Liandra Freitas; Arvelos, Letícia Ramos; Paraíso, Lara Ferreira; Penha-Silva, Nilson

    2011-12-01

    The action of glucose as an osmolyte in relation to blood cells is not well-characterized in the literature. This study aimed to study the influence of glucose concentration on the stability of red blood cells. The stability of erythrocytes was evaluated by the half-transition point obtained from the curves of lysis induced by glucose in the absence of salt or by increase in medium hypotonicity in the absence and the presence of different concentrations of glucose. In the presence of 0.9 g/dl NaCl, there was no hemolysis with increasing concentration of glucose from 0 to 10 g/dl. In the absence of NaCl, the dependence of hemolysis with the 0-10 g/dl glucose was described by a decreasing sigmoid, with fully lysed and fully protected cells being encountered in the presence of 0-2 and 4-10 g/dl glucose, respectively. The possible origin of such stabilization effect is discussed with base of what is known about osmostabilization of biological complexes and about the influence of glucose on the rheological properties of erythrocytes. PMID:21735128

  9. High-resolution surface plasmon resonance biosensing system for glucose concentration detecting

    NASA Astrophysics Data System (ADS)

    Huang, Xian; Li, Dachao; Yu, Haixia; Huang, Fuxiang; Hu, Xiaotang; Xu, Kexin

    2007-02-01

    Glucose is one of the most important substances widely contained in organism and food, thus people pay much attention in researching and improving the way for the detection of glucose. Traditional ways, although precise and reliable when in high concentration and large amount of sample, have unconvincing performance in detecting mixture and solution with low concentration and micro-volume. As far as the ideal way is concerned, it should not only specifically detect the glucose and exclude other components in solution, but also meet the need of micro-sample (approximately 5μL) and low concentration. We introduced D-galactose/D-glucose Binding Protein (GGBP) - a kind of protein which has the ability to absorb the glucose specifically, to construct a novel surface plasmon resonance measuring system. By immobilizing GGBP onto the surface of the SPR sensor, we develop a new detecting system for glucose testing in mixed solution. The experimental result indicates that compared with 0.1g/L before immobilization of GGBP, the detecting limit or the resolution of glucose testing rises to 1mg/L after the immobilization, the system succeeds in distinguishing glucose from other components in mixture, which reveals a bright future to apply SPR in the minimally invasive diabetes testing and food quality control.

  10. Capsaicin exposure elicits complex airway defensive motor patterns in normal humans in a concentration-dependent manner.

    PubMed

    Vovk, A; Bolser, D C; Hey, J A; Danzig, M; Vickroy, T; Berry, R; Martin, A D; Davenport, P W

    2007-01-01

    The airway defensive response to tussive agents, such as capsaicin, is frequently assessed by counting the number of cough sounds, or expulsive events. This method does not identify or differentiate important respiratory events that occur in the respiratory muscles and lungs, which are critical in assessing airway defensive responses. The purpose of this study was to characterize the airway defensive behaviours (cough and expiration reflex) to capsaicin exposure in humans. We observed complex motor behaviours in response to capsaicin exposure. These behaviours were defined as cough reacceleration (CRn) and expiration reflex (ERn), where n is the number of expulsive events with and without a preceding inspiratory phase, respectively. Airway defensive responses were defined in terms of frequency (number of expulsive events), strength (activation of abdominal muscles) and behaviour type (CRn vs. ERn). Thirty-six subjects (15 females, 24+/-4 yr) were instrumented with EMG electrodes placed over the rectus abdominis (RA), external abdominal oblique (EO) and the 8th intercostal space (IC8). A custom-designed mouth pneumotachograph was used to assess the airflow acceleration, plateau velocity and phase duration of the expulsive phase. Subjects inhaled seven concentrations of capsaicin (5-200 microM) in a randomized block order. The total number of expulsive events (frequency) and the sum of integrated EMG for the IC8, RA and EO (strength) increased in a curvilinear fashion. Differentiating the airway defense responses into type demonstrated predominately CR1 and CR2 (i.e. inspiration followed by one and two expulsive events, respectively) with very few ER's at <50 microM capsaicin. At higher concentrations (>50 microM) ER's with one or more expulsive events (ER1) appeared, and the number of CR's with three or more expulsive events (CR3) increased. The decrease in EMG activation and airflow measurements with each successive expulsive event suggests a decline in power and

  11. 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

  12. An integrated optical sensor for measuring glucose concentration

    NASA Astrophysics Data System (ADS)

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

    1992-01-01

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

  13. The Effects of Oxygen Level and Glucose Concentration on the Metabolism of Porcine TMJ Disc Cells

    PubMed Central

    Cisewski, Sarah E.; Zhang, Lixia; Kuo, Jonathan; Wright, Gregory J.; Wu, Yongren; Kern, Michael J.; Yao, Hai

    2015-01-01

    Objective To determine the combined effect of oxygen level and glucose concentration on cell viability, ATP production, and matrix synthesis of temporomandibular joint (TMJ) disc cells. Design TMJ disc cells were isolated from pigs aged 6-8 months and cultured in a monolayer. Cell cultures were preconditioned for 48 hours with 0, 1.5, 5, or 25mM glucose DMEM under 1%, 5%, 10%, or 21% O2 level, respectively. The cell viability was measured using the WST-1 assay. ATP production was determined using the Luciferin-Luciferase assay. Collagen and proteoglycan synthesis were determined by measuring the incorporation of [2, 3-3H]proline and [35S]sulfate into the cells, respectively. Results TMJ disc cell viability significantly decreased (P<0.0001) without glucose. With glucose present, decreased oxygen levels significantly increased viability (P<0.0001), while a decrease in glucose concentration significantly decreased viability (P<0.0001). With glucose present, decreasing oxygen levels significantly reduced ATP production (P<0.0001) and matrix synthesis (P<0.0001). A decreased glucose concentration significantly decreased collagen synthesis (P<0.0001). The interaction between glucose and oxygen was significant in regards to cell viability (P<0.0001), ATP production (P=0.00015), and collagen (P=0.0002) and proteoglycan synthesis (P<0.0001). Conclusions Although both glucose and oxygen are important, glucose is the limiting nutrient for TMJ disc cell survival. At low oxygen levels, the production of ATP, collagen, and proteoglycan are severely inhibited. These results suggest that steeper nutrient gradients may exist in the TMJ disc and it may be vulnerable to pathological events that impede nutrient supply. PMID:26033165

  14. The Association between Concentrations of Green Tea and Blood Glucose Levels.

    PubMed

    Maruyama, Koutatsu; Iso, Hiroyasu; Sasaki, Satoshi; Fukino, Yoko

    2009-01-01

    Our objective was to examine whether habitual green tea consumption is associated with blood glucose levels and other biomarkers of glucose metabolism. We conducted a cross-sectional study of 35 male volunteers, 23-63 years old and residing in Shizuoka Prefecture in Japan. Biochemical data were measured and we conducted a questionnaire survey on health, lifestyle, and nutrition, as well as frequency of consumption and concentrations (1%, 2%, and 3%) of green tea. Men who consumed a 3% concentration of green tea showed lower mean values of fasting blood glucose and fructosamine than those who consumed a 1% concentration. Fasting blood glucose levels were found to be significantly associated with green tea concentration (beta = -0.14, p = 0.03). However, green tea consumption frequency showed no significant differences in mean levels of blood glucose, fructosamine and hemoglobin A(1c.) In conclusion, our findings suggest that the consumption of green tea at a high concentration has the potential to reduce blood glucose levels.

  15. Pre-germinated brown rice reduced both blood glucose concentration and body weight in Vietnamese women with impaired glucose tolerance.

    PubMed

    Bui, Thi Nhung; Le, Thi Hop; Nguyen, Do Huy; Tran, Quang Binh; Nguyen, Thi Lam; Le, Danh Tuyen; Nguyen, Do Van Anh; Vu, Anh Linh; Aoto, Hiromichi; Okuhara, Yasuhide; Ito, Yukihiko; Yamamoto, Shigeru; Kise, Mitsuo

    2014-01-01

    We have reported that newly diagnosed type 2 diabetes mellitus (DM) patients in Vietnam have a low body mass index (BMI) of around 23 and that the major factor for this is high white rice (WR) intake. Brown rice (BR) is known to be beneficial in the control of blood glucose levels; however, it has the property of unpleasant palatability. Pre-germinated brown rice (PGBR) is slightly germinated by soaking BR in water as this reduces the hardness of BR and makes it easier to eat. This study was designed to evaluate the effect of a 4-mo PGBR administration on various parameters in Vietnamese women aged 45-65 y with impaired glucose tolerance (IGT). Sixty subjects were divided into a WR or PGBR group. For the first 2 wk, WR was replaced by 50% PGBR, then for 2 wk by 75% PGBR and from the second month 100%. Before the beginning of the study and at the end of the study, 1) anthropometric measurements, 2) a nutrition survey for 3 nonconsecutive days by the 24 h recall method and 3) blood biochemical examinations were conducted. Fasting plasma concentrations of glucose and lipids and the obesity-related measurements and blood pressure were favorably improved only in the PGBR diet group. The present results suggest that replacing WR with PGBR for 4 mo may be useful in controlling body weight as well as blood glucose and lipid levels in Vietnamese women with IGT.

  16. Evaluation of the serum fructosamine test to monitor plasma glucose concentration in the transition dairy cow.

    PubMed

    Sorondo, María L; Cirio, Alberto

    2009-05-01

    The usefulness of the serum fructosamine (Fser) to monitor the retrospective glucose concentrations in transitional dairy cows (n=17) was evaluated. In weekly blood samples (3 weeks before to 5 weeks after calving) concentrations of plasma glucose and serum fructosamine, beta-hydroxybutyrate (beta OHB) and total proteins were determined. The observed Fser concentrations (271+/-55 mean value, range 152-423 mumol/l) were within the range reported in the literature, and showed a progressive and significant decrease after calving. Mean plasma glucose concentration was 60.6+/-5.0 (range 39.9-82.2) mg/dl increasing from week 3 before calving to the week of calving and then decreasing during the next 5 weeks of lactation. This decrease was coincident with inverse relationships between plasma glucose and milk yield (P=0.03) and serum beta OHB (P<0.001). Linear regression analysis performed between serum fructosamine and (a) plasma glucose concentration of the same sampling and (b) plasma glucose concentration of 1, 2 and 3 weeks preceding the sampling, did not show significant and systematizing positive correlations. Persistent hypoproteinaemias that could affect the fructosamine concentrations were not found: mean value and range of serum proteins was 6.3+/-1.0 and 4.8-7.8 g/dl, respectively, and no correlation was found between serum proteins and Fser (P=0.26). Results did not support the possibility of retrospective monitoring of the plasma glucose concentration by serum fructosamine in dairy cows in the transition period.

  17. Determining diabetes prevalence: a rational basis for the use of fasting plasma glucose concentrations?

    PubMed

    Finch, C F; Zimmet, P Z; Alberti, K G

    1990-08-01

    The World Health Organization and the National Diabetes Data Group each recommend a diagnostic cut-off point for diabetes of 7.8 mmol l-1 for fasting plasma glucose concentrations as part of the diagnostic criteria for epidemiological studies. However, this cut-off has been shown to be insensitive compared with a screening test based on 2-h plasma glucose levels. In thirteen Pacific populations, from four ethnic groups (Asian Indian, Melanesian, Micronesian, and Polynesian), we have examined whether a different cut-off point for fasting plasma glucose would be more accurate for obtaining an estimate of the prevalence of diabetes when compared with 2-h levels. A fasting plasma glucose diagnostic cut-off of 7.0 mmol l-1 gave an estimate of prevalence not significantly different from that based on the 2-h plasma glucose in 12 of the 13 populations (mean difference 0.27, range -1.51 to +2.44,%). On the other hand, when a cut-off of 7.8 mmol l-1 for fasting plasma glucose was used, the resulting prevalence over-estimated the 2-h glucose prevalence in all populations (mean difference 1.91, range 0.14-5.80,%). Thus for Pacific populations, a fasting plasma glucose cut-off of 7.0 mmol l-1 provides estimates of prevalence that are equivalent to those based on 2-h plasma glucose levels. In epidemiological studies designed to estimate diabetes prevalence, we recommend use of a fasting plasma glucose cut-off of 7.0 mmol l-1 in preference to a detection level of 7.8 mmol l-1, if glucose loading is not possible.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. 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.

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

    PubMed

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

    2016-01-01

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

  20. Cell lineage allocation in equine blastocysts produced in vitro under varying glucose concentrations.

    PubMed

    Choi, Young-Ho; Ross, Pablo; Velez, Isabel C; Macías-García, B; Riera, Fernando L; Hinrichs, Katrin

    2015-07-01

    Equine embryos develop in vitro in the presence of high glucose concentrations, but little is known about their requirements for development. We evaluated the effect of glucose concentrations in medium on blastocyst development after ICSI. In experiment 1, there were no significant differences in rates of blastocyst formation among embryos cultured in our standard medium (DMEM/F-12), which contained >16 mM glucose, and those cultured in a minimal-glucose embryo culture medium (<1 mM; Global medium, GB), with either 0 added glucose for the first 5 days, then 20 mM (0-20) or 20 mM for the entire culture period (20-20). In experiment 2, there were no significant differences in the rates of blastocyst development (31-46%) for embryos cultured in four glucose treatments in GB (0-10, 0-20, 5-10, or 5-20). Blastocysts were evaluated by immunofluorescence for lineage-specific markers. All cells stained positively for POU5F1. An inner cluster of cells was identified that included presumptive primitive endoderm cells (GATA6-positive) and presumptive epiblast (EPI) cells. The 5-20 treatment resulted in a significantly lower number of presumptive EPI-lineage cells than the 0-20 treatment did. GATA6-positive cells appeared to be allocated to the primitive endoderm independent of the formation of an inner cell mass, as was previously hypothesized for equine embryos. These data demonstrate that equine blastocyst development is not dependent on high glucose concentrations during early culture; rather, environmental glucose may affect cell allocation. They also present the first analysis of cell lineage allocation in in vitro-fertilized equine blastocysts. These findings expand our understanding of the factors that affect embryo development in the horse.

  1. Prevalence of morning hyperglycaemia: determinants of fasting blood glucose concentrations in insulin-treated diabetics.

    PubMed

    Francis, A J; Home, P D; Walford, S; Alberti, K G; Mann, N; Reeves, W G

    1985-03-01

    A rise in blood glucose concentration at the end of the night, and consequent morning hyperglycaemia, are well recognized events in some diabetic patients. In 94 patients on twice daily insulin injections we have examined the prevalence and extent of morning hyperglycaemia, and its relation to control, insulin therapy, and insulin antibody levels. Blood glucose reached the highest level of the day before or after breakfast in 83% of patients, and in 50% this value was 2 mmol/l greater than any other time of day. Patients with higher fasting concentrations did not have worse blood glucose control over the rest of the day. No correlation was found between fasting blood glucose concentrations and the evening dose of intermediate acting insulin or the level of insulin antibodies. No consistent change in fasting blood glucose concentrations occurred with changes in antibody levels in patients switched between pork and beef insulin. Morning hyperglycaemia was as common with both insulin species. Pre- and post-breakfast hyperglycaemia is common and significant in insulin-treated diabetic patients. It is not directly related to diabetic control at other times of the day, and is independent of insulin species and insulin antibody levels.

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

    PubMed Central

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

    2013-01-01

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

  3. 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). PMID:26071437

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

    PubMed

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

    2014-01-01

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

  5. 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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2011-10-01

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

  8. Freeze-thawing behaviour of highly concentrated aqueous alkali chloride-glucose systems.

    PubMed

    Kajiwara, K; Motegi, A; Murase, N

    2001-01-01

    The freeze-thawing behaviour of highly concentrated aqueous alkali chloride-glucose systems was investigated by differential scanning calorimetry (DSC). In the aqueous NaCl-glucose solution system, single or double glass transitions followed by the corresponding devitrification exotherms were observed during rewarming. In the aqueous KCl-glucose solution system, on the other hand, a single glass transition followed by an exotherm was observed during rewarming. The presence of double glass transitions observed for a certain composition of the aqueous NaCl-glucose solution was taken as an evidence for the liquid-liquid immiscibility at low temperatures. Two kinds of crystallisation accompanied by exotherms during rewarming were identified by X-ray diffraction as ice and ice/NaCl x 2H(2)O, or ice/KCl eutectic component. PMID:11788873

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

    PubMed

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

    2015-10-05

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

  10. Lactate and glucose concentrations in brain interstitial fluid, cerebrospinal fluid, and serum during experimental pneumococcal meningitis.

    PubMed

    Guerra-Romero, L; Täuber, M G; Fournier, M A; Tureen, J H

    1992-09-01

    Metabolic abnormalities during bacterial meningitis include hypoglycorrhachia and cerebrospinal fluid (CSF) lactate accumulation. The mechanisms by which these alterations occur within the central nervous system (CNS) are still incompletely delineated. To determine the evolution of these changes and establish the locus of abnormal metabolism during meningitis, glucose and lactate concentrations in brain interstitial fluid, CSF, and serum were measured simultaneously and sequentially during experimental pneumococcal meningitis in rabbits. Interstitial fluid samples were obtained from the frontal cortex and hippocampus by using in situ brain microdialysis, and serum and CSF were directly sampled. There was an increase of CSF lactate concentration, accompanied by increased local production of lactate in the brain, and a decrease of CSF-to-serum glucose ratio that was paralleled by a decrease in cortical glucose concentration. Brain microdialysate lactate concentration was not affected by either systemic lactic acidosis or artificially elevated CSF lactate concentration. These data support the hypothesis that the brain is a locus for anaerobic glycolysis during meningitis, resulting in increased lactate production and perhaps contributing to decreased tissue glucose concentration.

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

    PubMed

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

    2015-01-01

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

  12. 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

  13. 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.

  14. 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.

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

    PubMed Central

    Ashok, Vajravelu; Kumar, Nirmal

    2013-01-01

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

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

    PubMed

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

    2016-05-01

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

  17. 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

  18. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

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

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

    SciTech Connect

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

    2010-01-15

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

  1. 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.

  2. Glucose ameliorates the metabolic profile and mitochondrial function of platelet concentrates during storage in autologous plasma

    PubMed Central

    Amorini, Angela M.; Tuttobene, Michele; Tomasello, Flora M.; Biazzo, Filomena; Gullotta, Stefano; De Pinto, Vito; Lazzarino, Giuseppe; Tavazzi, Barbara

    2013-01-01

    Background It is essential that the quality of platelet metabolism and function remains high during storage in order to ensure the clinical effectiveness of a platelet transfusion. New storage conditions and additives are constantly evaluated in order to achieve this. Using glucose as a substrate is controversial because of its potential connection with increased lactate production and decreased pH, both parameters triggering the platelet lesion during storage. Materials and methods In this study, we analysed the morphological status and metabolic profile of platelets stored for various periods in autologous plasma enriched with increasing glucose concentrations (13.75, 27.5 and 55 mM). After 0, 2, 4, 6 and 8 days, high energy phosphates (ATP, GTP, ADP, AMP), oxypurines (hypoxanthine, xanthine, uric acid), lactate, pH, mitochondrial function, cell lysis and morphology, were evaluated. Results The data showed a significant dose-dependent improvement of the different parameters in platelets stored with increasing glucose, compared to what detected in controls. Interestingly, this phenomenon was more marked at the highest level of glucose tested and in the period of time generally used for platelet transfusion (0–6 days). Conclusion These results indicate that the addition of glucose during platelet storage ameliorates, in a dose-dependent manner, the biochemical parameters related to energy metabolism and mitochondrial function. Since there was no correspondence between glucose addition, lactate increase and pH decrease in our experiments, it is conceivable that platelet derangement during storage is not directly caused by glucose through an increase of anaerobic glycolysis, but rather to a loss of mitochondrial functions caused by reduced substrate availability. PMID:22682337

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

    PubMed

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

    2016-01-01

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

  4. 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.

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

    PubMed Central

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

    2015-01-01

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

  6. 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.

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

    PubMed

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

    2011-05-01

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

  8. 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.

  9. 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.

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

    SciTech Connect

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

    1988-07-01

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

  11. 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. PMID:22886556

  12. 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.

  13. Cholesterol and unsaturated fat diets influence lipid and glucose concentrations in rats.

    PubMed

    Adamopoulos, P N; Papamichael, C M; Zampelas, A; Moulopoulos, S D

    1996-03-01

    The present study investigated the effects of dietary cholesterol and monounsaturated and polyunsaturated fatty acids on plasma lipids and glucose concentrations. Four groups of ten male Wistar albino rats were fed diets of different fatty acid composition for 40 days. The control group consumed nonpurified diet (containing fat 3.7 g/100 g diet), and cholesterol, olive oil, and safflower oil groups consumed the nonpurified diet enriched with 14 g fat/100 g diet with egg yolk, olive oil, or safflower oil, respectively. Compared with the control, the diet enriched with cholesterol significantly increased fasting plasma cholesterol (P < 0.01), triacylglycerol (P < 0.01), total lipid (P < 0.01) and glucose (P < 0.05) concentrations; in the olive oil group, cholesterol and triacylglycerol levels were significantly increased compared with control group (P < 0.01 in both instances). In safflower oil group, triacylglycerol levels were also significantly increased (P < 0.05) compared with the controls. After comparing diets providing the same amount of fat (cholesterol, olive oil, and safflower oil groups), higher cholesterol, triacylglycerol and total lipid levels were observed in the cholesterol group than in the olive oil group (P < 0.01, P < 0.05 and P < 0.01, respectively), and safflower oil group (P < 0.01 in all instances). High-density lipoprotein-cholesterol concentrations were significantly lower in the cholesterol group than in the olive oil and safflower oil groups (P < 0.05 in both instances) and fasting plasma glucose levels were higher in the cholesterol than in the olive oil (P < 0.05) and safflower oil groups (P < 0.01). Finally, after comparing lipid and glucose levels in the unsaturated fatty acids-enriched diets, higher plasma cholesterol concentrations were observed in the olive oil than in the safflower oil group (P < 0.05). These data suggest that not only the amount but also the type of dietary fat can influence serum lipid levels.

  14. 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.

  15. 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

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

    PubMed

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

    2013-05-21

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

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

    PubMed

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

    2013-05-21

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

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

    PubMed Central

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2009-02-01

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

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

    PubMed Central

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

    2015-01-01

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

  1. 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.

  2. 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.

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

    PubMed

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

    2016-06-01

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

  4. 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.

  5. Sub-chronic inhalation of high concentrations of manganese sulfate induces lower airway pathology in rhesus monkeys

    PubMed Central

    Dorman, David C; Struve, Melanie F; Gross, Elizabeth A; Wong, Brian A; Howroyd, Paul C

    2005-01-01

    lung manganese concentrations and small airway inflammatory changes in the absence of observable clinical signs. Subchronic exposure to manganese sulfate at exposure concentrations (≤0.3 mg Mn/m3) similar to the current 8-hr occupational threshold limit value established for inhaled manganese was not associated with pulmonary pathology. PMID:16242036

  6. In vivo noninvasive monitoring of glucose concentration in human epidermis by mid-infrared pulsed photoacoustic spectroscopy.

    PubMed

    Pleitez, Miguel A; Lieblein, Tobias; Bauer, Alexander; Hertzberg, Otto; von Lilienfeld-Toal, Hermann; Mäntele, Werner

    2013-01-15

    The noninvasive determination of glucose in the interstitial layer of the human skin by mid-infrared spectroscopy is reported. The sensitivity for this measurement was obtained by combining the high pulse energy from an external cavity quantum cascade laser (EC-QCL) tunable in the infrared glucose fingerprint region (1000-1220 cm(-1)) focused on the skin, with a detection of the absorbance process by photoacoustic spectroscopy in the ultrasound region performed by a gas cell coupled to the skin. This combination facilitates a quantitative measurement for concentrations of skin glucose in the range from <50 mg/dL to >300 mg/dL, which is the relevant range for the glucose monitoring in diabetes patients. Since the interstitial fluid glucose level is representative of the blood glucose level and follows it without significant delay (<10 min), this method could be applied to establish a noninvasive, painless glucose measurement procedure that is urgently awaited by diabetes patients. We report here the design of the photoacoustic experiments, the spectroscopy of glucose in vivo, and the calibration method for the quantitative determination of glucose in skin. Finally, a preliminary test with healthy volunteers and volunteers suffering from diabetes mellitus demonstrates the viability of a noninvasive glucose monitoring for patients based on the combination of infrared QCL and photoacoustic detection.

  7. Effect of initial glucose concentrations on carbon material and energy balances in hydrogen-producing Clostridium tyrobutyricum JM1.

    PubMed

    Jo, Ji Hye; Lee, Dae Sung; Kim, Junhoon; Park, Jong Moon

    2009-03-01

    The carbon metabolism of newly isolated Clostridium tyrobutyricum JM1 was investigated at varying initial glucose concentrations (27.8-333.6mM). Because an understanding of metabolic regulations was required to provide guidance for further effective metabolic design or optimization, in this case, maximizing hydrogen production, carbon material, and energy balances by C. tyrobutyricum JM1 were determined and applied in anaerobic glucose metabolism. The overall carbon distribution suggested that initial glucose concentrations had strong influence on the stoichiometric coefficients of products and the molar production of ATP on the formation of biomass. C. tyrobutyricum JM1 had a high capacity for hydrogen production at the initial glucose concentration of 222.4 mM with high concentrations of acetate and butyrate.

  8. Glucose, insulin concentrations and obesity in childhood and adolescence as predictors of NIDDM.

    PubMed

    McCance, D R; Pettitt, D J; Hanson, R L; Jacobsson, L T; Bennett, P H; Knowler, W C

    1994-06-01

    Metabolic abnormalities antedate the development of non-insulin-dependent diabetes mellitus (NIDDM) by some years. How these metabolic abnormalities relate to the genetic component of the disease and to the subsequent prediction of diabetes is unknown. The present study was designed to examine the association of parental diabetes with relative weight, fasting and 2-h plasma glucose and fasting and 2-h serum insulin in childhood, and to identify which of these variables were most predictive of subsequent NIDDM. Subjects comprised 1258 Pima Indians aged 5-19 years with normal glucose tolerance participating in a longitudinal population-based study. Age-sex-adjusted values of relative weight, fasting and 2-h glucose and fasting and 2-h insulin were positively associated with parental diabetes. Only one of 138 subjects with two non-diabetic parents developed diabetes. Among 1120 subjects with at least one diabetic parent, 101 (9.0%) developed diabetes during a mean follow up of 8.4 years. Fasting insulin was a significant predictor of diabetes, but did not add to the predictive value of relative weight. Relative weight and 2-h and fasting plasma glucose were the variables most predictive of NIDDM in childhood and adolescence. Against a background of parental diabetes, high fasting insulin concentrations predict diabetes, compatible with the hypothesis that insulin resistance is an early metabolic abnormality leading to NIDDM. In this study, however, its predictive power did not add significantly to that of relative weight, with which it was correlated.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. 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

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

    PubMed

    Jo, Ji Hye; Kim, Woong

    2016-06-20

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

  11. 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.

  12. 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.

  13. 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. PMID:23514230

  14. Studies of Human Adipose Tissue in Culture III INFLUENCE OF INSULIN AND MEDIUM GLUCOSE CONCENTRATION ON CELLULAR METABOLISM

    PubMed Central

    Smith, Ulf

    1974-01-01

    Explants of human adipose tissue were maintained in culture for 1 wk in different glucose concentrations with or without the addition of insulin. After this period of time the explants were carefully washed and then subjected to short-term incubations in the same glucose concentration and in the absence of insulin. With this experimental design the influence of long-term exposure to insulin and different glucose concentrations on adipose tissue metabolism could be studied. The results of these studies show that an increase in the glucose concentration of the culture medium enhanced the basal as well as the catecholamine-stimulated lipolysis in the short-term incubations. The presence of insulin in the culture medium enhanced the lipolytic process as well. Analogous results were obtained with the cellular rate of glucose conversion to triglycerides in the short-term incubations. The stimulating effects of insulin and glucose were most pronounced in the larger adipose cells possibly due to their enlarged surface areas. The data suggest that the metabolism of adipose tissue as revealed by short-term studies may be profoundly influenced by the antecedent biochemical environment. PMID:4808648

  15. A Low Frequency Electromagnetic Sensor for Indirect Measurement of Glucose Concentration: In Vitro Experiments in Different Conductive Solutions

    PubMed Central

    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. PMID:22219665

  16. 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.

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

    PubMed Central

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

    2015-01-01

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

  18. 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.

  19. 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. PMID:26713213

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed Central

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

    2008-01-01

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

  2. Surgical Airway

    PubMed Central

    Patel, Sapna A; Meyer, Tanya K

    2014-01-01

    Close to 3% of all intubation attempts are considered difficult airways, for which a plan for a surgical airway should be considered. Our article provides an overview of the different types of surgical airways. This article provides a comprehensive review of the main types of surgical airways, relevant anatomy, necessary equipment, indications and contraindications, preparation and positioning, technique, complications, and tips for management. It is important to remember that the placement of a surgical airway is a lifesaving procedure and should be considered in any setting when one “cannot intubate, cannot ventilate”. PMID:24741501

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

    PubMed

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

    2003-07-01

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

  4. 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.

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

    PubMed

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

    2006-02-01

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

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

    PubMed

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

    2006-02-01

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

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

    PubMed Central

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

    2015-01-01

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

  8. Pasta supplemented with isolated lupin protein fractions reduces body weight gain and food intake of rats and decreases plasma glucose concentration upon glucose overload trial.

    PubMed

    Capraro, Jessica; Magni, Chiara; Scarafoni, Alessio; Caramanico, Rosita; Rossi, Filippo; Morlacchini, Mauro; Duranti, Marcello

    2014-02-01

    The supplementation of foods with biologically active compounds can be a powerful approach for improving diet and well being. In this study we separately included in pasta matrices a concentrate of γ-conglutin, a glucose-lowering protein from Lupinus albus seeds, an isolate of the other main lupin storage proteins and ovalbumin, at a ratio corresponding to 125 mg of pure protein in 100 g of pasta. With these products we fed rats made hyperglycaemic, for 3 weeks. Among the most relevant changes measured in body and blood parameters were: (i) a significant reduction in food intake of rats fed γ-conglutin concentrate supplemented pasta and a significant limitation in the body weight increase in rats fed α, β and δ-conglutin isolate supplemented pasta, while the food conversion indices were unchanged; (ii) a reduction in glycaemia upon glucose overload trial, especially in the γ-conglutin concentrate supplemented pasta fed animals, at a dose of 45 mg per kg body weight. The correlations among the measured parameters are discussed. Overall, the results evidence the potentiality of supplementing traditional foods with exogenous nutraceutical seed proteins to control body weight gain and glycaemia.

  9. 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.

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

    PubMed

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

    2012-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2015-07-01

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

  14. 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%.

  15. 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.

  16. Metabolic response to MMS-mediated DNA damage in Saccharomyces cerevisiae is dependent on the glucose concentration in the medium.

    PubMed

    Kitanovic, Ana; Walther, Thomas; Loret, Marie Odile; Holzwarth, Jinda; Kitanovic, Igor; Bonowski, Felix; Van Bui, Ngoc; Francois, Jean Marie; Wölfl, Stefan

    2009-06-01

    Maintenance and adaptation of energy metabolism could play an important role in the cellular ability to respond to DNA damage. A large number of studies suggest that the sensitivity of cells to oxidants and oxidative stress depends on the activity of cellular metabolism and is dependent on the glucose concentration. In fact, yeast cells that utilize fermentative carbon sources and hence rely mainly on glycolysis for energy appear to be more sensitive to oxidative stress. Here we show that treatment of the yeast Saccharomyces cerevisiae growing on a glucose-rich medium with the DNA alkylating agent methyl methanesulphonate (MMS) triggers a rapid inhibition of respiration and enhances reactive oxygen species (ROS) production, which is accompanied by a strong suppression of glycolysis. Further, diminished activity of pyruvate kinase and glyceraldehyde-3-phosphate dehydrogenase upon MMS treatment leads to a diversion of glucose carbon to glycerol, trehalose and glycogen accumulation and an increased flux through the pentose-phosphate pathway. Such conditions finally result in a significant decline in the ATP level and energy charge. These effects are dependent on the glucose concentration in the medium. Our results clearly demonstrate that calorie restriction reduces MMS toxicity through increased respiration and reduced ROS accumulation, enhancing the survival and recovery of cells.

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

    PubMed

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

    1998-01-01

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

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

    PubMed Central

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

    2013-01-01

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

  1. 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.

  2. Effect of Dipyridamole Injected for Myocardial Perfusion Imaging on Blood Glucose Concentration; A Preliminary Study

    PubMed Central

    Arabi, Mohsen; Akhavein, Alireza; Seyedabadi, Mohammad; Eftekhari, Mansooreh; Javadi, Hamid; Nabipour, Iraj; Assadi, Majid

    2016-01-01

    Introduction Dipyridamole inhibits adenosine reuptake and increases cyclic Adenosine Monophosphate (cAMP) levels in platelets, erythrocytes and endothelial cells, all of which influence blood glucose. Acute hyperglycaemia reduces endothelium-dependent vasodilation and suppresses coronary microcirculation; which, in theory, can alter the outcome of a radionuclide scan. Aim The present study was conducted with the aim to investigate the changes in blood glucose level of patients receiving dipyridamole for cardiac scan. Materials and Methods A total of 293 patients (85 men and 208 women, age: 60.59±10.43 years) were included in the study. Fasting Blood Glucose (FBG) was measured before and 8 min after dipyridamole (0.568 mg/kg) injection during myocardial perfusion imaging. The data in different groups were analysed by paired t-test. Results There was not a significant difference between first (106.89 ± 19.21mg/dL) and second (107.98 ± 17.57 mg/dL) FBG measurements (p= 0.293). However, when the patients were grouped based on the quartiles of first measurement, there was an increase in FBG following dipyridamole injection in the first quartile (mean difference: 7.15±21.27 mg/dL, p<0.01); in contrast, FBG levels showed a significant decrease after dipyridamole administration in the 4th quartile (mean difference: -9.53±18.20 mg/dL, p<0.001). The differences in 2nd and 3rd quartiles were negligible. The patients were divided into normal, ischemic and fixed lesions based on the outcome of scans, then the possible correlation of dipyridamole-induced FBG alteration and scan results were investigated. There were no significant difference between the FBG values before and after dipyridamole injection and the final outcome of scan. Conclusion The effects of dipyridamole on blood glucose highly depend on the initial blood glucose level. PMID:27656528

  3. 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

  4. Concomitant Intake of Quercetin with a Grain-Based Diet Acutely Lowers Postprandial Plasma Glucose and Lipid Concentrations in Pigs

    PubMed Central

    Wein, Silvia; Wolffram, Siegfried

    2014-01-01

    Treatment goals of diabetes mellitus type 2 (DMT2) include glycemic control and reduction of nonglycemic risk factors, for example, dyslipidemia. Quercetin, a plant-derived polyphenol, often discussed for possible antidiabetic effects, was investigated for acute postprandial glucose- and lipid-lowering effects in healthy growing pigs. Male pigs (n = 16, body weight = BW 25–30 kg) were fed flavonoid-poor grain-based meals without (GBM) or with quercetin (GBMQ). In a first experiment, postprandial plasma concentrations of glucose, nonesterified fatty acids (NEFA), and triacylglycerols were analyzed in 8 pigs receiving 500 g of either GBM or GBMQ (10 mg/kg BW) in a cross-over design. Blood samples were collected before, and up to 5 h every 30 min, as well as 6 and 8 h after the feeding. In the second experiment, 2 h after ingestions of 1000 g of either GBM or GBMQ (50 mg/kg BW) animals were sacrificed; gastric content was collected and analyzed for dry matter content. Quercetin ingestion reduced postprandial glucose, NEFA, and TG concentration, but two hours after ingestion of the meal no effect on gastric emptying was observed. Our results point to inhibitory effects of quercetin on nutrient absorption, which appear not to be attributable to delayed gastric emptying. PMID:24847478

  5. 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.

  6. Distinct H2O2 concentration promotes proliferation of tumour cells after transient oxygen/glucose deprivation.

    PubMed

    Schild, Lorenz; Makarow, Petr; Haroon, Fahad; Krautwald, Karla; Keilhoff, Gerburg

    2008-03-01

    A solid tumour undergoes ischemia/reperfusion due to deficient vascularization and subsequent formation of new blood vessels. This study investigated the effect of transient oxygen and glucose deprivation (OGD) on proliferation of C6 glioma cells. The cells were subjected to 18 h of OGD followed by reoxygenation in the presence of glucose and different extra-cellular H(2)O(2) concentrations since H(2)O(2) affects cell proliferation. After reoxygenation, the cellular H(2)O(2) concentration was increased returning to control levels within 24 h. Within this period, increase in cell number and MTT-reduction were impaired. Regeneration was completed on the third day of reoxygenation. MTT-reduction increased faster than cell number, indicating an OGD-dependent up-regulation of protein expression. It is concluded that ischemia/reperfusion stress promotes proliferation of tumour cells. An essential factor is a distinct H(2)O(2) concentration. Massive elevation as well as significant reduction of H(2)O(2) concentration impairs the proliferation process. PMID:18344118

  7. 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.

  8. Changes in metabolic enzymes, cortisol and glucose concentrations of Beluga (Huso huso) exposed to dietary methylmercury.

    PubMed

    Gharaei, Ahmad; Ghaffari, Mostafa; Keyvanshokooh, Saeed; Akrami, Reza

    2011-09-01

    In this paper, effects of dietary methylmercury (MeHg) on several blood biochemical parameters including GLU (glucose), LDH (lactate dehydrogenase), AST (aspartate aminotransferase), ALT (alanine aminotransferase), ALP (alkaline phosphatase) and cortisol were investigated in the Beluga sturgeon (Huso huso). Beluga juveniles were fed for 32 days on four diets containing MeHg (control: 0.04 mg kg⁻¹; low: 0.76 mg kg⁻¹; medium: 7.88 mg kg⁻¹; and high 16.22 mg kg⁻¹ treatment). Significant increases (P < 0.05) were observed in all biochemical parameters, except ALP levels, which decreased significantly (P < 0.05) compared to the control group with either dose- or time-dependent effects. These results suggest that long-term dietary MeHg exposure may affect metabolic enzyme activity and glucose levels in Belugas. These findings provide useful information for environmental and fishery officials to apply in future decisions for managing fish resources in Caspian Sea.

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

    PubMed Central

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

    2015-01-01

    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 (r2 = 0.97). We observed no significant differences in the dose responses for glucose stimulation of respiration, NAD(P)H autofluorescence, or Ca2+ responses between left- and right-shifted β-cells. However, a left shift in the sensitivity of exocytosis to Ca2+ 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. PMID:25934392

  10. 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. PMID:19069917

  11. 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

  12. Comparison of a Point-of-Care Glucometer and a Laboratory Autoanalyzer for Measurement of Blood Glucose Concentrations in Domestic Pigeons ( Columba livia domestica).

    PubMed

    Mohsenzadeh, Mahdieh Sadat; Zaeemi, Mahdieh; Razmyar, Jamshid; Azizzadeh, Mohammad

    2015-09-01

    Biochemical analysis is necessary for diagnosis and monitoring of diseases in birds; however, the small volume of blood that can be safely obtained from small avian species often limits laboratory diagnostic testing. Consequently, a suitable methodology requiring only a small volume of blood must be used. This study was designed to compare blood glucose concentrations in domestic pigeons ( Columba livia domestica) as measured by a commercial, handheld, human glucometer and a standard autoanalyzer. During the first phase of the study, whole blood samples obtained from 30 domestic pigeons were used to measure the blood glucose concentration with a glucometer, the packed cell volume (PCV), and the total erythrocyte count (nRBC). Plasma separated from the each sample was then used to obtain the plasma glucose concentration with the autoanalyzer. During the second phase of the study, 30 pigeons were assigned to 2 equal groups (n = 15). Hypoglycemia or hyperglycemia was induced in each group by intravenous injection of insulin or glucose, respectively. Blood was collected and processed, and glucose concentrations, PCV, and nRBC were measured as previously described. Linear-regression models demonstrated a significant relationship between results measured by the glucometer and autoanalyzer results from normoglycemic (correlation coefficient [R] = 0.43, P = .02), hypoglycemic (R = 0.95; P < .001), and hyperglycemic (R = 0.81; P < .001) birds. The results of this study suggest that we can predict the real blood-glucose concentration of pigeons by using results obtained by a glucometer.

  13. 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

  14. 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.

  15. Discrete wavelength selection for the optical readout of a metamaterial biosensing system for glucose concentration estimation via a support vector regression model.

    PubMed

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

    2015-01-01

    In this contribution, a method to select discrete wavelengths that allow an accurate estimation of the glucose concentration in a biosensing system based on metamaterials is presented. The sensing concept is adapted to the particular application of ophthalmic glucose sensing by covering the metamaterial with a glucose-sensitive hydrogel and the sensor readout is performed optically. Due to the fact that in a mobile context a spectrometer is not suitable, few discrete wavelengths must be selected to estimate the glucose concentration. The developed selection methods are based on nonlinear support vector regression (SVR) models. Two selection methods are compared and it is shown that wavelengths selected by a sequential forward feature selection algorithm achieves an estimation improvement. The presented method can be easily applied to different metamaterial layouts and hydrogel configurations.

  16. Glucose-stimulated oscillations in free cytosolic ATP concentration imaged in single islet beta-cells: evidence for a Ca2+-dependent mechanism.

    PubMed

    Ainscow, Edward K; Rutter, Guy A

    2002-02-01

    Normal glucose-stimulated insulin secretion is pulsatile, but the molecular mechanisms underlying this pulsatility are poorly understood. Oscillations in the intracellular free [ATP]/[ADP] ratio represent one possible mechanism because they would be expected to cause fluctuations in ATP-sensitive K(+) channel activity and hence oscillatory Ca(2+) influx. After imaging recombinant firefly luciferase, expressed via an adenoviral vector in single human or mouse islet beta-cells, we report here that cytosolic free ATP concentrations oscillate and that these oscillations are affected by glucose. In human beta-cells, oscillations were observed at both 3 and 15 mmol/l glucose, but the oscillations were of a longer wavelength at the higher glucose concentration (167 vs. 66 s). Mouse beta-cells displayed oscillations in both cytosolic free [Ca(2+)] and [ATP] only at elevated glucose concentrations, both with a period of 120 s. To explore the causal relationship between [Ca(2+)] and [ATP] oscillations, the regulation of each was further investigated in populations of MIN6 beta-cells. Incubation in Ca(2+)-free medium lowered cytosolic [Ca(2+)] but increased [ATP] in MIN6 cells at both 3 and 30 mmol/l glucose. Removal of external Ca(2+) increased [ATP], possibly by decreasing ATP consumption by endoplasmic reticulum Ca(2+)-ATPases. These results allow a model to be constructed of the beta-cell metabolic oscillator that drives nutrient-induced insulin secretion.

  17. 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

  18. Modelling ischaemia in vitro: effects of temperature and glucose concentration on dopamine release evoked by oxygen and glucose depletion in a mouse brain slice.

    PubMed

    Davidson, C; Chauhan, N K; Knight, S; Gibson, C L; Young, A M J

    2011-11-15

    Current pharmacological interventions for acute stroke are largely ineffective or confounded by adverse effects, emphasising the need to develop new pharmacological treatments for neuroprotection. We have developed a robust in vitro model previously used in rats to assess dopamine release in mouse caudate nucleus brain slices, measured by fast cyclic voltammetry, during oxygen and glucose deprivation (OGD) as a model for cerebral ischaemia: this model will allow the study of transgenic mouse strains. During the pre-OGD equilibration period we found that a temperature of 33°C, with solution containing 10 mM glucose provided the optimum baseline conditions from which reliable OGD-induced changes in dopamine efflux could be measured, without being susceptible to spontaneous release events. During OGD we found no significant difference in any of the parameters measured between perfusion with glucose-free solution, and perfusion with solution containing 2 mM glucose. We therefore suggest, in agreement with previous work, that using 2 mM glucose during OGD is appropriate, and using these conditions we were able to reliably produce OGD-evoked dopamine release. PMID:21669225

  19. Modelling ischaemia in vitro: effects of temperature and glucose concentration on dopamine release evoked by oxygen and glucose depletion in a mouse brain slice.

    PubMed

    Davidson, C; Chauhan, N K; Knight, S; Gibson, C L; Young, A M J

    2011-11-15

    Current pharmacological interventions for acute stroke are largely ineffective or confounded by adverse effects, emphasising the need to develop new pharmacological treatments for neuroprotection. We have developed a robust in vitro model previously used in rats to assess dopamine release in mouse caudate nucleus brain slices, measured by fast cyclic voltammetry, during oxygen and glucose deprivation (OGD) as a model for cerebral ischaemia: this model will allow the study of transgenic mouse strains. During the pre-OGD equilibration period we found that a temperature of 33°C, with solution containing 10 mM glucose provided the optimum baseline conditions from which reliable OGD-induced changes in dopamine efflux could be measured, without being susceptible to spontaneous release events. During OGD we found no significant difference in any of the parameters measured between perfusion with glucose-free solution, and perfusion with solution containing 2 mM glucose. We therefore suggest, in agreement with previous work, that using 2 mM glucose during OGD is appropriate, and using these conditions we were able to reliably produce OGD-evoked dopamine release.

  20. Failure of human and mouse leptin to affect insulin, glucagon and somatostatin secretion by the perfused rat pancreas at physiological glucose concentration.

    PubMed

    Leclercq-Meyer, V; Malaisse, W J

    1998-06-25

    In isolated perfused pancreas from normal rats, a rise in d-glucose concentration from 3.3 to 8.3 mM provoked a rapid phasic stimulation of both insulin and somatostatin secretion and rapid fall in glucagon output, these changes being reversed when the concentration of the hexose was brought back to its initial low level. In the presence of 8.3 mM d-glucose, the administration of either human or mouse leptin (10 nM in both cases) for 15 min failed to affect significantly the perfusion pressure and release of the three hormones. It is concluded that leptin does not exert any major immediate and direct effect upon pancreatic insulin, glucagon and somatostatin secretion, at least at the physiological concentration of d-glucose normally found in the plasma of fed rats. PMID:9723892

  1. 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.

  2. Obesity and upper airway control during sleep

    PubMed Central

    Patil, Susheel P.; Squier, Samuel; Schneider, Hartmut; Kirkness, Jason P.; Smith, Philip L.

    2010-01-01

    Mechanisms linking obesity with upper airway dysfunction in obstructive sleep apnea are reviewed. Obstructive sleep apnea is due to alterations in upper airway anatomy and neuromuscular control. Upper airway structural alterations in obesity are related to adipose deposition around the pharynx, which can increase its collapsibility or critical pressure (Pcrit). In addition, obesity and, particularly, central adiposity lead to reductions in resting lung volume, resulting in loss of caudal traction on upper airway structures and parallel increases in pharyngeal collapsibility. Metabolic and humoral factors that promote central adiposity may contribute to these alterations in upper airway mechanical function and increase sleep apnea susceptibility. In contrast, neural responses to upper airway obstruction can mitigate these mechanical loads and restore pharyngeal patency during sleep. Current evidence suggests that these responses can improve with weight loss. Improvements in these neural responses with weight loss may be related to a decline in systemic and local pharyngeal concentrations of specific inflammatory mediators with somnogenic effects. PMID:19875707

  3. 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.

  4. High concentrations of glucose suppress etoposide-induced cell death of B-cell lymphoma through BCL-6.

    PubMed

    Shao, Yan; Ling, Chang Chun; Liu, Xu Qing

    2014-07-18

    Glucose is potentially a factor in the resistance to chemotherapy of B-cell lymphomas. In this study we investigated the expression of the glucose induced transcription factor Bcl-6 and the underlying mechanism by which it suppresses B-cell lymphoma cell death. Glucose was found to prevent etoposide-induced tumor cell death. BCL-6 expression was induced by glucose but down-regulated by etoposide. BCL-6 expression was regulated by the interaction of VDUP1 and p53. The molecular mechanism by which glucose prevented etoposide-induced tumor cell death was shown to involve the BCL-6 mediated caspase pathway. Our data suggest that glucose-induced BCL-6 overexpression could abrogate the etoposide chemotherapy effect on tumor cell death. PMID:24878528

  5. 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

  6. Short communication: plasma concentration of glucose-dependent insulinotropic polypeptide may regulate milk energy production in lactating dairy cows.

    PubMed

    Relling, A E; Crompton, L A; Loerch, S C; Reynolds, C K

    2014-01-01

    In dairy cows, an increase in plasma concentration of glucose-dependent insulinotropic polypeptide (GIP) is associated with an increase in metabolizable energy intake, but the role of GIP in energy partitioning of dairy cattle is not certain. The objective of this study was to examine the relationship between plasma GIP concentrations and energy partitioning toward milk production. Four mid-lactation, primiparous, rumen-fistulated Holstein-Friesian cows were fed a control diet of 55% forage and 45% concentrate [dry matter (DM) basis] in a 4×4 Latin square design with 4-wk periods. The 4 treatments were (1) control diet fed at 1000 and 1600h, and (2) once-daily (1000h) feeding, (3) twice-daily (1000 and 1600h) feeding, and (4) 4 times/d (1000, 1600, 2200 and 0400h) feeding of the control diet plus 1 dose (1.75kg on a DM basis at 0955h) into the rumen of supplemental vegetable proteins (Amino Green; SCA NuTec Ltd., Thirsk, UK). Measurements of respiratory exchange and energy balance were obtained over 4d during the last week of each period while cows were housed in open-circuit respiration chambers. Blood was collected from the jugular vein every 30min for 12h, using indwelling catheters, starting at 0800h on d 20 of each period. Plasma GIP concentration was measured in samples pooled over each 5 consecutive blood samplings. The relationships between plasma GIP, DM intake, heat production, respiratory quotient (RQ), milk yield, and milk energy output were analyzed using linear correlation procedures, with metabolizable intake as a partial variant. Plasma GIP concentration was not correlated with heat production, or milk yield, but was positively correlated with milk energy yield (correlation coefficient=0.67) and negatively correlated with RQ (correlation coefficient=-0.72). The correlations between GIP with RQ and milk energy output do not imply causality, but support a role for GIP in the regulation of energy metabolism in dairy cows.

  7. 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. PMID:3533597

  8. Effects of isoleucine on glucose uptake through the enhancement of muscular membrane concentrations of GLUT1 and GLUT4 and intestinal membrane concentrations of Na+/glucose co-transporter 1 (SGLT-1) and GLUT2.

    PubMed

    Zhang, Shihai; Yang, Qing; Ren, Man; Qiao, Shiyan; He, Pingli; Li, Defa; Zeng, Xiangfang

    2016-08-01

    Knowledge of regulation of glucose transport contributes to our understanding of whole-body glucose homoeostasis and human metabolic diseases. Isoleucine has been reported to participate in regulation of glucose levels in many studies; therefore, this study was designed to examine the effect of isoleucine on intestinal and muscular GLUT expressions. In an animal experiment, muscular GLUT and intestinal GLUT were determined in weaning pigs fed control or isoleucine-supplemented diets. Supplementation of isoleucine in the diet significantly increased piglet average daily gain, enhanced GLUT1 expression in red muscle and GLUT4 expression in red muscle, white muscle and intermediate muscle (P<0·05). In additional, expressions of Na+/glucose co-transporter 1 and GLUT2 were up-regulated in the small intestine when pigs were fed isoleucine-supplemented diets (P<0·05). C2C12 cells were used to examine the expressions of muscular GLUT and glucose uptake in vitro. In C2C12 cells supplemented with isoleucine in the medium, cellular 2-deoxyglucose uptake was increased (P<0·05) through enhancement of the expressions of GLUT4 and GLUT1 (P<0·05). The effect of isoleucine was greater than that of leucine on glucose uptake (P<0·05). Compared with newborn piglets, 35-d-old piglets have comparatively higher GLUT4, GLUT2 and GLUT5 expressions. The results of this study demonstrated that isoleucine supplementation enhanced the intestinal and muscular GLUT expressions, which have important implications that suggest that isoleucine could potentially increase muscle growth and intestinal development by enhancing local glucose uptake in animals and human beings. PMID:27464458

  9. 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.

  10. Alterations in blood glucose and plasma glucagon concentrations during deep brain stimulation in the shell region of the nucleus accumbens in rats.

    PubMed

    Diepenbroek, Charlene; van der Plasse, Geoffrey; Eggels, Leslie; Rijnsburger, Merel; Feenstra, Matthijs G P; Kalsbeek, Andries; Denys, Damiaan; Fliers, Eric; Serlie, Mireille J; la Fleur, Susanne E

    2013-01-01

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) is an effective therapy for obsessive compulsive disorder (OCD) and is currently under investigation as a treatment for eating disorders. DBS of this area is associated with altered food intake and pharmacological treatment of OCD is associated with the risk of developing type 2 diabetes. Therefore we examined if DBS of the NAc-shell (sNAc) influences glucose metabolism. Male Wistar rats were subjected to DBS, or sham stimulation, for a period of 1 h. To assess the effects of stimulation on blood glucose and glucoregulatory hormones, blood samples were drawn before, during and after stimulation. Subsequently, all animals were used for quantitative assessment of Fos immunoreactivity in the lateral hypothalamic area (LHA) using computerized image analysis. DBS of the sNAc rapidly increased plasma concentrations of glucagon and glucose while sham stimulation and DBS outside the sNAc were ineffective. In addition, the increase in glucose was dependent on DBS intensity. In contrast, the DBS-induced increase in plasma corticosterone concentrations was independent of intensity and region, indicating that the observed DBS-induced metabolic changes were not due to corticosterone release. Stimulation of the sNAc with 200 μA increased Fos immunoreactivity in the LHA compared to sham or 100 μA stimulated animals. These data show that DBS of the sNAc alters glucose metabolism in a region- and intensity- dependent manner in association with neuronal activation in the LHA. Moreover, these data illustrate the need to monitor changes in glucose metabolism during DBS-treatment of OCD patients. PMID:24339800

  11. Glucose enhances insulin promoter activity in MIN6 beta-cells independently of changes in intracellular Ca2+ concentration and insulin secretion.

    PubMed Central

    Kennedy, H J; Rafiq, I; Pouli, A E; Rutter, G A

    1999-01-01

    Recent studies have suggested that glucose may activate insulin gene transcription through increases in intracellular Ca(2+) concentration, possibly acting via the release of stored insulin. We have investigated this question by dynamic photon-counting imaging of insulin- and c-fos-promoter-firefly luciferase reporter construct activity. Normalized to constitutive viral promoter activity, insulin promoter activity in MIN6 beta-cells was increased 1.6-fold after incubation at 30 mM compared with 3 mM glucose, but was unaltered at either glucose concentration by the presence of insulin (100 nM) or the Ca(2+) channel inhibitor, verapamil (100 microM). Increases in intracellular [Ca(2+)] achieved by plasma membrane depolarization with KCl failed to enhance either insulin or c-fos promoter activity in MIN6 cells, but increased c-fos promoter activity 5-fold in AtT20 cells. Together, these results demonstrate that glucose can exert a direct effect on insulin promoter activity in islet beta-cells, via a signalling pathway which does not require increases in intracellular [Ca(2+)] nor insulin release and insulin receptor activation. PMID:10455011

  12. Growth as a solid tumor or reduced glucose concentrations in culture reversibly induce CD44-mediated hyaluronan recognition by Chinese hamster ovary cells.

    PubMed Central

    Zheng, Z; Cummings, R D; Pummill, P E; Kincade, P W

    1997-01-01

    The density, molecular isoform, and posttranslational modifications of CD44 can markedly influence growth and metastatic behavior of tumors. Many CD44 functions, including some involving tumors, have been attributed to its ability to recognize hyaluronan (HA). However, only certain CD44-bearing cells bind soluble or immobilized HA. We now show that CD44 made by wild-type Chinese hamster ovary (CHO-K1) cells and a ligand-binding subclone differ with respect to N-linked glycosylation. While both bear CD44 with highly branched, complex-type glycoforms, CD44 expressed by the wild type was more extensively sialylated. CHO-K1 cells which failed to recognize HA when grown in culture gained this ability when grown as a solid tumor and reverted to a non-HA-binding state when returned to culture. The ability of CHO-K1 cells to recognize HA was also reversibly induced when glucose concentrations in the medium were reduced. Glucose restriction influenced CD44-mediated HA binding by many but not all, of a series of murine tumors. Glucose concentrations and glycosylation inhibitors only partially influenced CD44 receptor function on resting murine B lymphocytes. These observations suggest that glucose levels or other local environmental conditions may markedly influence glycosylation pathways used by some tumor cells, resulting in dramatic alteration of CD44-mediated functions. PMID:9276740

  13. The effect of glucose, insulin and noradrenaline on lipolysis and on the concentrations of adenosine 3′:5′-cyclic monophosphate and adenosine 5′-triphosphate in adipose tissue

    PubMed Central

    Knight, Brian L.; Iliffe, Jill

    1973-01-01

    Glycerol release and tissue concentrations of ATP and cyclic AMP were followed during the incubation of adipose tissue with or without glucose, insulin and noradrenaline. Glucose plus insulin or, to a lesser extent, glucose alone increased the accumulation of glycerol during incubations both with and without noradrenaline by slowing the decline in the rate of glycerol release with time. Insulin alone decreased the accumulation by accelerating the fall in glycerol release. In the absence of noradrenaline, ATP and cyclic AMP concentrations were not significantly affected by insulin or glucose. With noradrenaline or noradrenaline plus insulin the ATP concentration gradually fell. With noradrenaline plus glucose the ATP concentration fell rapidly and then stabilized, or, if insulin was also present, returned to the control value. In the presence of noradrenaline, the concentration of cyclic AMP rose during the first 20min and then fell. Insulin lowered the peak concentration of cyclic AMP, but glucose had no effect either on the peak value or the fall in the concentration of the nucleotide. The increase and fall in the concentration of cyclic AMP with noradrenaline or noradrenaline plus insulin bore similarities to the increase and decline in the lipolytic rate in incubations without glucose. It is proposed that glucose stimulates ATP production by furnishing glycerol 1-phosphate and thus removing free fatty acids, but that it can influence lipolysis by a mechanism which is distinct from any which is mediated by free fatty acids, possibly by inhibiting the inactivation of the lipase. PMID:4353001

  14. Emergency airway puncture

    MedlinePlus

    Emergency airway puncture is the placement of a hollow needle through the throat into the airway. It ... efforts to assist with breathing have failed. A hollow needle or tube can be inserted into the ...

  15. At diabetes-like concentration, glucose down-regulates the placental serotonin transport system in a cell-cycle-dependent manner.

    PubMed

    Unal, R; Ahmed, B A; Jeffus, B C; Harney, J T; Lyle, C S; Wu, Y-K; Chambers, T C; Reece, E A; Kilic, F

    2007-05-01

    Serotonin [5-hydroxytryptamine (5HT)] is a vasoconstrictor that also acts as a developmental signal early in embryogenesis. The 5HT transporter (SERT) on the membranes of the placental trophoblast cells controls 5HT levels in the maternal bloodstream to maintain stable transplacental blood flow and simultaneously provide 5HT to the embryo. The 5HT uptake rate of placental SERT is important for both the mother and the developing embryo. The impact of glucose on the placental SERT system during diabetic pregnancy is not known. The present in vitro study investigated this important issue in human placental choriocarcinoma (JAR) cells that were cultured for 24-96 h in a medium containing either 5.5 (physiologic concentration) or 25 mmol/L D-glucose (diabetic-like concentration). The 5HT uptake rates of the cultured cells were not altered at exogenous D-glucose concentrations in the range of 5.5-15 mmol/L, but were decreased significantly at a diabetic-like concentration (>or=25 mmol/L). To understand better the role of glucose on the placental 5HT system, we first characterized SERT in JAR cells at different cell-cycle phases and then determined the expression levels of SERT on the plasma membrane and in the intracellular pools of JAR cells at the late-S and G2 phases, where the uptake rates were decreased 73% under diabetic-like glucose concentrations. Finally, the importance of self-association of SERT molecules was examined. In JAR cells co-expressing Flag- and myc-tagged SERT, myc-antibody precipitated 70% of Flag-SERT, indicating that a large percentage of SERT proteins exist as oligomers in situ. Under diabetic conditions, myc-antibody no longer precipitated Flag-SERT, suggesting a disruption in the aggregation of SERT molecules. Therefore, we propose that under uncontrolled diabetic conditions, glucose down-regulates 5HT uptake rates of placental SERT by interfering with its functional expression in a cell-cycle-dependent manner.

  16. 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…

  17. 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).

  18. 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.

  19. Effects of high and moderate non-structural carbohydrate hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings.

    PubMed

    Shepherd, M L; Pleasant, R S; Crisman, M V; Werre, S R; Milton, S C; Swecker, W S

    2012-06-01

    The objective of this study was to determine the effects of high and moderate non-structural carbohydrates (NSC) hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings. Eight adult overweight (average BCS 7 [9-point scale]) Arabian geldings were fed each of two orchardgrass hays, high NSC (18% DM) and moderate NSC (12% DM), in a cross over design during two 28-day periods. Body weight and body condition score assessment along with blood sampling to measure insulin, glucose, leptin, and triglyceride concentrations were performed on days 0, 7, 14, 21 and 28 of each period. Effects of hay, period, day, and day*hay on plasma glucose and serum leptin were not detected. Serum insulin was influenced by hay (p = 0.001), day (p = 0.03), and day*hay (p = 0.04). Insulin concentrations were higher on day 7 in the high NSC group (15.6 μIU/ml) than the moderate NSC group (9.5 μIU/ml), but not by day 14 (p = 0.0007). Plasma triglyceride was influenced by period (p = 0.0003), day*period (p < 0.0001), and day*hay (p = 0.02). Hyperinsulinaemia was not observed in the overweight Arabian geldings fed either a moderate or high NSC hay. PMID:21575079

  20. Comparison of a human portable glucometer and an automated chemistry analyzer for measurement of blood glucose concentration in pet ferrets (Mustela putorius furo).

    PubMed

    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.

  1. 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

  2. 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

  3. Biosensor based on excessively tilted fiber grating in thin-cladding optical fiber for sensitive and selective detection of low glucose concentration.

    PubMed

    Luo, Binbin; Yan, Zhijun; Sun, Zhongyuan; Liu, Yong; Zhao, Mingfu; Zhang, Lin

    2015-12-14

    We report a highly sensitive, high Q-factor, label free and selective glucose sensor by using excessively tilted fiber grating (Ex-TFG) inscribed in the thin-cladding optical fiber (TCOF). Glucose oxidase (GOD) was covalently immobilized on optical fiber surface and the effectiveness of GOD immobilization was investigated by the fluorescence microscopy and highly accurate spectral interrogation method. In contrast to the long period grating (LPG) and optical fiber (OF) surface Plasmon resonance (SPR) based glucose sensors, the Ex-TFG configuration has merits of nearly independent cross sensitivity of the environmental temperature, simple fabrication method (no noble metal deposition or cladding etching) and high detection accuracy (or Q-factor). Our experimental results have shown that Ex-TFG in TCOF based sensor has a reliable and fast detection for the glucose concentration as low as 0.1~2.5mg/ml and a high sensitivity of ~1.514 nm·(mg/ml)⁻¹, which the detection accuracy is ~0.2857 nm⁻¹ at pH 5.2, and the limit of detection (LOD) is 0.013~0.02 mg/ml at the pH range of 5.2~7.4 by using an optical spectrum analyzer with a resolution of 0.02 nm. PMID:26699032

  4. Glucose, memory, and aging.

    PubMed

    Korol, D L; Gold, P E

    1998-04-01

    Circulating glucose concentrations regulate many brain functions, including learning and memory. Much of the evidence for this view comes from experiments assessing stress-related release of epinephrine with subsequent increases in blood glucose concentrations. One application of this work has been to investigate whether age-related memory impairments result from dysfunctions in the neuroendocrine regulation of the brain processes responsible for memory. Like humans, aged rodents exhibit some memory impairments that can be reversed by administration of epinephrine or glucose. In elderly humans, ingestion of glucose enhances some cognitive functions, with effects best documented thus far on tests of verbal contextual and noncontextual information. Glucose also effectively enhances cognition in persons with Alzheimer disease or Down syndrome. Although earlier evidence suggested that glucose does not enhance cognitive function in healthy young adults, more recent findings suggest that glucose is effective in this population, provided the tests are sufficiently difficult. In college students, glucose consumption significantly enhanced memory of material in a paragraph. Glucose also appeared to enhance attentional processes in these students. Neither face and word recognition nor working memory was influenced by treatment with glucose. The neurobiological mechanisms by which glucose acts are under current investigation. Initial evidence suggests that glucose or a metabolite may activate release of the neurotransmitter acetylcholine in rats when they are engaged in learning. Consequently, the issue of nutrition and cognition becomes increasingly important in light of evidence that circulating glucose concentrations have substantial effects on brain and cognitive functions.

  5. The emergency airway.

    PubMed

    Goon, Serena S H; Stephens, Robert C M; Smith, Helen

    2009-12-01

    The 'can't intubate, can't ventilate' scenario is a nightmare for all clinicians who manage airways. Cricothyroidotomy is one of several emergency airway management techniques. Cricothyroidotomy is a short-term solution which provides oxygenation, not ventilation, and is not a definitive airway. Although there are tests which can help predict whether an intubation will be difficult, they are not always good predictors. As the can't intubate, can't ventilate scenario is rare, cricothyroidotomy is an unfamiliar procedure to many. In this situation, expert help must be called for early on. In the meantime, it is vital that all other simple airway manoeuvres have been attempted, such as good positioning of the patient with head tilt and chin lift, and use of airway adjuncts like the oral (Guedel) airway or nasopharyngeal airway, and the laryngeal mask airway. However, if attempts to secure the airway are unsuccessful, there may be no other option than to perform a cricothyroidotomy. It is a difficult decision to make, but with increasing hypoxia, it is essential that one oxygenates the patient. Cricothyroidotomy provides an opening in the pace between the anterior inferior border of the thyroid cartilage and the anterior superior border of the cricoid cartilage, allowing access to the airway below the glottis. The anatomical considerations are important when performing this procedure (Ellis, 2009), and there are other scenarios when it is used. It is not without consequence, as with any procedure.

  6. 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.

  7. Engineering Airway Epithelium

    PubMed Central

    Soleas, John P.; Paz, Ana; Marcus, Paula; McGuigan, Alison; Waddell, Thomas K.

    2012-01-01

    Airway epithelium is constantly presented with injurious signals, yet under healthy circumstances, the epithelium maintains its innate immune barrier and mucociliary elevator function. This suggests that airway epithelium has regenerative potential (I. R. Telford and C. F. Bridgman, 1990). In practice, however, airway regeneration is problematic because of slow turnover and dedifferentiation of epithelium thereby hindering regeneration and increasing time necessary for full maturation and function. Based on the anatomy and biology of the airway epithelium, a variety of tissue engineering tools available could be utilized to overcome the barriers currently seen in airway epithelial generation. This paper describes the structure, function, and repair mechanisms in native epithelium and highlights specific and manipulatable tissue engineering signals that could be of great use in the creation of artificial airway epithelium. PMID:22523471

  8. 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. PMID:27234550

  9. Circulating concentrations of glucagon-like peptide 1, glucose-dependent insulinotropic peptide, peptide YY, and insulin in client-owned lean, overweight, and diabetic cats.

    PubMed

    McMillan, C J; Zapata, R C; Chelikani, P K; Snead, E C R; Cosford, K

    2016-01-01

    Our objectives were to measure plasma concentrations of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and peptide YY (PYY) in client-owned newly diagnosed diabetic cats and nondiabetic lean or overweight cats and to determine whether circulating concentrations of these hormones differed between study groups and if they increased postprandially as seen in other species. A total of 31 cats were recruited and placed into 1 of 3 study groups: lean (body condition score 4-5 on a scale of 1-9; n = 10), overweight (body condition score 6-8; n = 11), or diabetic (n = 10). Diabetics were newly diagnosed and had not had prior insulin therapy. Preprandial (fasting) and postprandial (60 min after meal) plasma hormone and glucose concentrations were measured at baseline and 2 and 4 wk. All cats were exclusively fed a commercially available high-protein and low-carbohydrate diet commonly prescribed to feline diabetic patients for 2 wk before the 2-wk assessment and continued through the 4-wk assessment. Results showed that plasma concentrations of GLP-1, GIP, PYY, and insulin increased in general after a meal in all study groups. Plasma PYY concentrations did not differ (P > 0.10) between study groups. Diabetics had greater plasma concentrations of GLP-1 and GIP compared with the other study groups at baseline (P < 0.05), and greater preprandial and postprandial GLP-1 concentrations than lean cats at 2 and 4 wk (P < 0.05). Preprandial plasma GIP concentrations were greater in diabetics than obese and lean (P < 0.05) cats at week 4. Postprandial plasma GIP concentrations in diabetics were greater than lean (P < 0.05) at week 2 and obese and lean cats (P < 0.05) at week 4. Together, our findings suggest that diabetic status is an important determinant of circulating concentrations of GLP-1 and GIP, but not PYY, in cats. The role of GLP-1, GIP, and PYY in the pathophysiology of feline obesity and diabetes remains to be determined.

  10. Prevalence of subclinical ketosis in dairy cattle in the Southwestern Iran and detection of cutoff point for NEFA and glucose concentrations for diagnosis of subclinical ketosis.

    PubMed

    Asl, Ardavan Nowroozi; Nazifi, Saeed; Ghasrodashti, Abbas Rowshan; Olyaee, Ahad

    2011-06-01

    Subclinical ketosis (SCK) is simply a condition marked by increased levels of circulating ketone bodies without the presence of the clinical signs of ketosis. Subclinical ketosis can cause economic losses through decreased milk production and association with preparturient diseases. Limited information is available regarding the prevalence of SCK in dairy herds in Southwestern Iran. The objectives of this study were (i) determination of the cutoff point of nonesterified fatty acids (NEFAs) and glucose concentrations for diagnosis of SCK using receiver operating characteristic (ROC) analysis, and (ii) determination of prevalence of subclinical ketosis in apparently healthy dairy cattle in Southwestern Iran. From October to December 2009, a total of 100 clinically healthy multiparous Holstein cows (3-8 years old) were randomly selected from 16 dairy herds around Kazerun, Fars Province, Iran. The cows had two-six lactations, with body weight ranging from 500 to 650 kg. Blood samples for each cow were taken at 2, 4 and 6 weeks post parturition and 3-4h after the morning feeding. The optimal cutoff point was set, by the ROC method, to >0.26 mmol/L for NEFA, and < 2.26 mmol/L for glucose with corresponding 82.54% sensitivity and 91.89% specificity for NEFA and 44.44% sensitivity and 78.38% specificity for glucose. Cows with BHB concentrations higher than 1200 μmol/L were classified as having SCK. In 2, 4 and 6 weeks post parturition 63%, 68% and 59% of the tested cows were subclinically ketotic. Overall, 97% of tested cows (97/100) were considered subclinically ketotic in at least one sample period. Thirty percent of tested cows (30/100) suffered from subclinical ketosis in all of the 2, 4 and 6 weeks postpartum. The results suggest that, a cut-off point of 0.26 mmol/L for NEFA concentrations can be used during early lactation for diagnosis of subclinical ketosis and making management decisions for prevention and treatment. Glucose cannot be a good criterion for

  11. Heterotrophic and mixotrophic growth of Micractinium pusillum Fresenius in the presence of acetate and glucose: effect of light and acetate gradient concentration.

    PubMed

    Bouarab, L; Dauta, A; Loudiki, M

    2004-06-01

    The main objective of this study was to determine the importance of secondary mechanism of organic carbon utilization (mixotrophic and heterotrophic modes) in addition to CO2 fixation (photoautotrophic mode) in the green alga, Micractinium pusillum Fresenius (chlorophyta), isolated from a waste stabilization pond. The growth was studied in the presence of acetate and glucose. The incorporation rate of 14C- acetate was measured in the light and in the dark at different concentrations. Finally, in order to underline the role of photosynthesis and respiration processes in the acetate assimilation, the effect of two specific metabolic inhibitors, a specific inhibitor of photosystem II (DCMU) and an uncoupler respiratory (DNP), has been studied. The obtained results showed that M. pusillum grows in the presence of organic substrates, i.e., glucose and acetate, in the light (mixotrophic growth) as well as in the dark (Heterotrophic growth). The growth was much more important in the light than in the dark and more in the presence of glucose than of acetate. In the light, the presence of acetate led to a variation of growth parameters mumax, iotaopt, and beta. The effect of acetate gradient on the growth of the microalga was severe as soon as its concentration in the medium was higher. The acetate uptake followed a Michaelis-Menten kinetic in the light as well as in the dark. The capacity of assimilation was slightly higher in the dark. The utilization of DNP and DCMU indicates that acetate incorporation is an active process depending on both anabolic (photosynthesis) and catabolic (respiration) metabolisms, corroborating the model of the Michaelis-Menten kinetic.

  12. 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

  13. Aldose reductase regulates acrolein-induced cytotoxicity in human small airway epithelial cells.

    PubMed

    Yadav, Umesh C S; Ramana, K V; Srivastava, Satish K

    2013-12-01

    Aldose reductase (AR), a glucose-metabolizing enzyme, reduces lipid aldehydes and their glutathione conjugates with more than 1000-fold efficiency (Km aldehydes 5-30 µM) relative to glucose. Acrolein, a major endogenous lipid peroxidation product as well as a component of environmental pollutants and cigarette smoke, is known to be involved in various pathologies including atherosclerosis, airway inflammation, COPD, and age-related disorders, but the mechanism of acrolein-induced cytotoxicity is not clearly understood. We have investigated the role of AR in acrolein-induced cytotoxicity in primary human small airway epithelial cells (SAECs). Exposure of SAECs to varying concentrations of acrolein caused cell death in a concentration- and time-dependent manner. AR inhibition by fidarestat prevented the low-dose (5-10 µM) but not the high-dose (>10 µM) acrolein-induced SAEC death. AR inhibition protected SAECs from low-dose (5 µM) acrolein-induced cellular reactive oxygen species (ROS). Inhibition of acrolein-induced apoptosis by fidarestat was confirmed by decreased condensation of nuclear chromatin, DNA fragmentation, comet tail moment, and annexin V fluorescence. Further, fidarestat inhibited acrolein-induced translocation of the proapoptotic proteins Bax and Bad from the cytosol to the mitochondria and that of Bcl2 and BclXL from the mitochondria to the cytosol. Acrolein-induced cytochrome c release from mitochondria was also prevented by AR inhibition. The mitogen-activated protein kinases (MAPKs), such as extracellular signal-regulated kinases 1 and 2, stress-activated protein kinase/c-Jun NH2-terminal kinase, and p38MAPK, and c-Jun were transiently activated in airway epithelial cells by acrolein in a concentration- and time-dependent fashion, which was significantly prevented by AR inhibition. These results suggest that AR inhibitors could prevent acrolein-induced cytotoxicity in the lung epithelial cells.

  14. 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.

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

    PubMed

    Karnchanasorn, Rudruidee; Huang, Jean; Ou, Horng-Yih; Feng, Wei; Chuang, Lee-Ming; Chiu, Ken C; Samoa, Raynald

    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/m(2), 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

  16. 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

  17. Management of the difficult airway.

    PubMed

    Strauss, Robert A; Noordhoek, Roseanna

    2010-03-01

    The oral and maxillofacial surgeon frequently encounters and manages difficult airways. Knowledge of and calm progression by practitioner and staff through different means to ventilate and manage a difficult airway are crucial. Practitioners should become comfortable with different types of alternative or rescue airways in order to intervene quickly in case of emergent or unanticipated airway compromise.

  18. 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

  19. Partial pressures of oxygen and carbon dioxide, pH, and concentrations of bicarbonate, lactate, and glucose in pleural fluid from horses.

    PubMed

    Brumbaugh, G W; Benson, P A

    1990-07-01

    Samples of pleural fluid from 20 horses with effusive pleural diseases of various causes were evaluated; samples from 19 horses were used for the study. There were differences for pH (P = 0.001) and partial pressure of oxygen (PO2) between arterial blood and nonseptic pleural fluid (P = 0.0491), but there were no differences for pH, PO2, partial pressure of carbon dioxide (PCO2), and concentrations of bicarbonate (HCO3-), lactate, and glucose between venous blood and nonseptic pleural fluid. Paired comparisons of venous blood and nonseptic pleural fluid from the same horse indicated no differences. There were differences (P = 0.0001, each) for pH, PO2, PCO2, and concentrations of HCO3- between arterial blood and septic pleural fluid. Differences also existed for pH (P = 0.0001), PCO2 (P = 0.0003), and concentrations of HCO3- (P = 0.0001), lactate (P = 0.0051), and glucose (P = 0.0001) between venous blood and septic pleural fluid. Difference was not found for values of PO2 between venous blood and septic pleural fluid, although 4 samples of septic pleural fluid contained virtually no oxygen. Paired comparisons of venous blood and septic pleural fluid from the same horse revealed differences (P less than 0.05) for all values, except those for PO2. These alterations suggested functional and physical compartmentalization that separated septic and healthy tissue. Compartmentalization and microenvironmental factors at the site of infection should be considered when developing therapeutic strategies for horses with septic pleural disease. PMID:2389879

  20. Insulin and glucose regulation.

    PubMed

    Ralston, Sarah L

    2002-08-01

    Abnormally high or low blood glucose and insulin concentrations after standardized glucose tolerance tests can reflect disorders such as pituitary dysfunction, polysaccharide storage myopathies, and other clinical disorders. Glucose and insulin responses, however, are modified by the diet to which the animal has adapted, time since it was last fed, and what it was fed. Body fat (obesity), fitness level, physiologic status, and stress also alter glucose and insulin metabolism. Therefore, it is important to consider these factors when evaluating glucose and insulin tests, especially if only one sample it taken. This article describes the factors affecting glucose and insulin metabolism in horses and how they might influence the interpretation of standardized tests of glucose tolerance.

  1. Blindness in dogs with pituitary dependent hyperadrenocorticism: relationship with glucose, cortisol and triglyceride concentration and with ophthalmic blood flow.

    PubMed

    Cabrera Blatter, M F; del Prado, A; Gallelli, M F; D'Anna, E; Ivanic, J; Esarte, M; Miceli, D D; Gómez, N V; Castillo, V A

    2012-06-01

    Pituitary dependent hyperadrenocorticism (PDH) shows a high morbidity and blindness is one of its complications. Compression of the optic chiasm (OC) by the hypophysis adenoma is one of the causes. Another cause could be due to vascular and metabolic alterations of the PDH. Out of a total of 70 dogs with confirmed diagnosis of PDH, 12/70 showed blindness. In only 2/12 the OC was compromised. Electroretinography in dogs without the OC being compromised showed altered A and B wave patterns. Ophthalmological Doppler showed an alteration of the blood flow only in blind dogs without OC compression. Cortisol concentrations (Co), triglycerides (Tg) and glycaemia (G) were greater in 10 dogs with non-compressive blindness vs. dogs with conserved vision. Loss of vision correlated with the increase in these variables. Blindness in dogs with PDH would be related to changes in retinal blood flow, associated to higher Co, Tg and G concentrations.

  2. 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.

  3. Airway management in trauma.

    PubMed

    Langeron, O; Birenbaum, A; Amour, J

    2009-05-01

    Maintenance of a patent and prevention of aspiration are essential for the management of the trauma patient, that requires experienced physicians in airway control techniques. Difficulties of the airway control in the trauma setting are increased by the vital failures, the risk of aspiration, the potential cervical spine injury, the combative patient, and the obvious risk of difficult tracheal intubation related to specific injury related to the trauma. Endotracheal intubation remains the gold standard in trauma patient airway management and should be performed via the oral route with a rapid sequence induction and a manual in-line stabilization maneuver, to decrease the risks previously mentioned. Different techniques to control the airway in trauma patients are presented: improvement of the laryngoscopic vision, lighted stylet tracheal intubation, retrograde technique for orotracheal intubation, the laryngeal mask and the intubating laryngeal mask airways, the combitube and cricothyroidotomy. Management of the airway in trauma patients requires regular training in these techniques and the knowledge of complementary techniques allowing tracheal intubation or oxygenation to overcome difficult intubation and to prevent major complications as hypoxemia and aspiration. PMID:19412149

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

    PubMed Central

    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. PMID:24004455

  5. 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...

  6. Role of upper airway ultrasound in airway management.

    PubMed

    Osman, Adi; Sum, Kok Meng

    2016-01-01

    Upper airway ultrasound is a valuable, non-invasive, simple, and portable point of care ultrasound (POCUS) for evaluation of airway management even in anatomy distorted by pathology or trauma. Ultrasound enables us to identify important sonoanatomy of the upper airway such as thyroid cartilage, epiglottis, cricoid cartilage, cricothyroid membrane, tracheal cartilages, and esophagus. Understanding this applied sonoanatomy facilitates clinician to use ultrasound in assessment of airway anatomy for difficult intubation, ETT and LMA placement and depth, assessment of airway size, ultrasound-guided invasive procedures such as percutaneous needle cricothyroidotomy and tracheostomy, prediction of postextubation stridor and left double-lumen bronchial tube size, and detecting upper airway pathologies. Widespread POCUS awareness, better technological advancements, portability, and availability of ultrasound in most critical areas facilitate upper airway ultrasound to become the potential first-line non-invasive airway assessment tool in the future. PMID:27529028

  7. Role of upper airway ultrasound in airway management.

    PubMed

    Osman, Adi; Sum, Kok Meng

    2016-01-01

    Upper airway ultrasound is a valuable, non-invasive, simple, and portable point of care ultrasound (POCUS) for evaluation of airway management even in anatomy distorted by pathology or trauma. Ultrasound enables us to identify important sonoanatomy of the upper airway such as thyroid cartilage, epiglottis, cricoid cartilage, cricothyroid membrane, tracheal cartilages, and esophagus. Understanding this applied sonoanatomy facilitates clinician to use ultrasound in assessment of airway anatomy for difficult intubation, ETT and LMA placement and depth, assessment of airway size, ultrasound-guided invasive procedures such as percutaneous needle cricothyroidotomy and tracheostomy, prediction of postextubation stridor and left double-lumen bronchial tube size, and detecting upper airway pathologies. Widespread POCUS awareness, better technological advancements, portability, and availability of ultrasound in most critical areas facilitate upper airway ultrasound to become the potential first-line non-invasive airway assessment tool in the future.

  8. 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

  9. Indirect airway challenges.

    PubMed

    Joos, G F; O'Connor, B; Anderson, S D; Chung, F; Cockcroft, D W; Dahlén, B; DiMaria, G; Foresi, A; Hargreave, F E; Holgate, S T; Inman, M; Lötvall, J; Magnussen, H; Polosa, R; Postma, D S; Riedler, J

    2003-06-01

    Indirect challenges act by causing the release of endogenous mediators that cause the airway smooth muscle to contract. This is in contrast to the direct challenges where agonists such as methacholine or histamine cause airflow limitation predominantly via a direct effect on airway smooth muscle. Direct airway challenges have been used widely and are well standardised. They are highly sensitive, but not specific to asthma and can be used to exclude current asthma in a clinic population. Indirect bronchial stimuli, in particular exercise, hyperventilation, hypertonic aerosols, as well as adenosine, may reflect more directly the ongoing airway inflammation and are therefore more specific to identify active asthma. They are increasingly used to evaluate the prevalence of bronchial hyperresponsiveness and to assess specific problems in patients with known asthma, e.g. exercise-induced bronchoconstriction, evaluation before scuba diving. Direct bronchial responsiveness is only slowly and to a modest extent, influenced by repeated administration of inhaled steroids. Indirect challenges may reflect more closely acute changes in airway inflammation and a change in responsiveness to an indirect stimulus may be a clinically relevant marker to assess the clinical course of asthma. Moreover, some of the indirect challenges, e.g. hypertonic saline and mannitol, can be combined with the assessment of inflammatory cells by induction of sputum.

  10. Ozone-induced modulation of airway hyperresponsiveness in guinea pigs.

    PubMed

    Schlesinger, Richard B; Cohen, Mitchell; Gordon, Terry; Nadziejko, Christine; Zelikoff, Judith T; Sisco, Maureen; Regal, Jean F; Ménache, Margaret G

    2002-06-01

    Although acute exposure to ozone (03*) has been shown to influence the severity and prevalence of airway hyperresponsiveness, information has been lacking on effects due to long-term exposure at relatively low exposure concentrations. The goals of this study were to determine whether long-term repeated ozone exposures could induce nonspecific hyperresponsiveness in normal, nonatopic (nonsensitized) animals, whether such exposure could exacerbate the preexisting hyperresponsive state in atopic (sensitized) animals, or both. The study was also designed to determine whether gender modulated airway responsiveness related to ozone exposure. Airway responsiveness was measured during and after exposure to 0.1 and 0.3 ppm ozone for 4 hours/day, 4 days/week for 24 weeks in normal, nonsensitized guinea pigs, in guinea pigs sensitized to an allergen (ovalbumin) prior to initiation of ozone exposures, and in animals sensitized concurrently with ozone exposures. Both male and female animals were studied. Ozone exposure did not produce airway hyperresponsiveness in nonsensitized animals. Ozone exposure did exacerbate airway hyperresponsiveness to specific and nonspecific bronchoprovocation in both groups of sensitized animals, and this effect persisted at least 4 weeks after the end of the exposures. Although the overall degree of airway responsiveness did differ between genders (males had more responsive airways than did females), the airway response to ozone exposure did not differ between the two groups. Ozone-induced effects upon airway responsiveness were not associated with the number of pulmonary eosinophils or with any chronic pulmonary inflammatory response. Levels of antigen-specific antibodies increased in sensitized animals, and a significant correlation was observed between airway responsiveness and antibody levels. The results of this study provide support for a role of ambient ozone exposure in exacerbation of airway dysfunction in persons with atopy.

  11. 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. PMID:18598183

  12. Airway statuses and nasopharyngeal airway use for airway obstruction in syndromic craniosynostosis.

    PubMed

    Kouga, Takeshi; Tanoue, Koji; Matsui, Kiyoshi

    2014-05-01

    Syndromic craniosynostosis is associated with a high rate of respiratory difficulty, due mainly to midfacial hypoplasia. Nasopharyngeal airway establishment has been reported as the first-line approach to airway obstruction and may obviate the need for a highly invasive tracheotomy. No previous studies have compared airway obstruction status in syndromic craniosynostosis between cases requiring and not requiring airway managements. We focus on nasopharyngeal airway use and airway status outcomes to assess respiratory difficulty in patients with syndromic craniosynostosis. A retrospective data analysis of 51 cases with syndromic craniosynostosis was carried out. We divided 30 of the 51 cases with lateral pharyngeal x-rays taken before operations affecting airway diameters into 2 groups, one with neither nasopharyngeal airway insertion nor tracheotomy and the other with one or both of these interventions, and the mean diameters for 8 indices related to the pharyngeal space were compared. Cases with respiratory difficulty due to nasopharyngeal stenosis and requiring airway managements comprised a significantly higher proportion of those with Pfeiffer syndrome than patients with Crouzon or Apert syndrome. Comparative examination of lateral x-ray cephalometry between cases with neither nasopharyngeal airway insertion nor tracheotomy and cases with one or both revealed oropharyngeal diameters tended to be smaller in those with interventions. Cases requiring nasopharyngeal airway insertion were able to continue nasopharyngeal airway use for more than 1 year and a considerable number avoided tracheotomy. It may be worth considering an oropharyngeal-bypass nasopharyngeal airway before performing a tracheotomy. PMID:24820706

  13. 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.

  14. Vascular Anomalies and Airway Concerns

    PubMed Central

    Clarke, Caroline; Lee, Edward I.; Edmonds, Joseph

    2014-01-01

    Vascular anomalies, both tumors and malformations, can occur anywhere in the body, including the airway, often without any external manifestations. However, vascular anomalies involving the airway deserve special consideration as proper recognition and management can be lifesaving. In this article, the authors discuss vascular anomalies as they pertains to the airway, focusing on proper diagnosis, diagnostic modalities, and therapeutic options. PMID:25045336

  15. Volatile Organic Compounds Contribute to Airway Hyperresponsiveness

    PubMed Central

    Jang, An-Soo; Choi, Inseon-S; Koh, Young-Il

    2007-01-01

    Background Volatile organic compounds (VOCs) in concentrations found in both the work and home environments may influence lung function. We investigated the prevalence of airway responsiveness in workers exposed to VOCs. Methods We used allergic skin tests, nonspecific airway hyperresponsiveness testing and questionnaires to study twenty exposed workers and twenty-seven control subjects. Atopy was defined as a reactor who showed >3+ response to one or more allergens on the skin prick tests. Airway hyperresponsiveness (BRindex) was defined as log [% fall of FEV1/ log (last concentration of methacholine) +10]. Results The VOC exposed workers, in comparison with the control subjects, tended to have a higher BRindex (1.19±0.07 vs. 1.15±0.08, respectively). Workers exposed to VOCs with atopy or smoker, as compared with the workers exposed to VOCs with non-atopy and who were non-smokers and the control subjects with non-atopy and who were non-smokers, had a significantly higher BRindex (1.20±0.05 vs. 1.14±0.06 vs. 1.10±0.03, respectively p<0.05). The BRindex was not correlated with atopy, the smoking status or the duration of VOC exposure. Conclusions These findings suggest that VOCs may act as a contributing factor of airway hyperresponsiveness in workers exposed to VOCs. PMID:17427638

  16. Adiponectin receptor-mediated signaling ameliorates cerebral cell damage and regulates the neurogenesis of neural stem cells at high glucose concentrations: an in vivo and in vitro study

    PubMed Central

    Song, J; Kang, S M; Kim, E; Kim, C-H; Song, H-T; Lee, J E

    2015-01-01

    In the central nervous system (CNS), hyperglycemia leads to neuronal damage and cognitive decline. Recent research has focused on revealing alterations in the brain in hyperglycemia and finding therapeutic solutions for alleviating the hyperglycemia-induced cognitive dysfunction. Adiponectin is a protein hormone with a major regulatory role in diabetes and obesity; however, its role in the CNS has not been studied yet. Although the presence of adiponectin receptors has been reported in the CNS, adiponectin receptor-mediated signaling in the CNS has not been investigated. In the present study, we investigated adiponectin receptor (AdipoR)-mediated signaling in vivo using a high-fat diet and in vitro using neural stem cells (NSCs). We showed that AdipoR1 protects cell damage and synaptic dysfunction in the mouse brain in hyperglycemia. At high glucose concentrations in vitro, AdipoR1 regulated the survival of NSCs through the p53/p21 pathway and the proliferation- and differentiation-related factors of NSCs via tailless (TLX). Hence, we suggest that further investigations are necessary to understand the cerebral AdipoR1-mediated signaling in hyperglycemic conditions, because the modulation of AdipoR1 might alleviate hyperglycemia-induced neuropathogenesis. PMID:26247729

  17. 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. PMID:27174647

  18. Total airway reconstruction.

    PubMed

    Connor, Matthew P; Barrera, Jose E; Eller, Robert; McCusker, Scott; O'Connor, Peter

    2013-02-01

    We present a case of obstructive sleep apnea (OSA) that required multilevel surgical correction of the airway and literature review and discuss the role supraglottic laryngeal collapse can have in OSA. A 34-year-old man presented to a tertiary otolaryngology clinic for treatment of OSA. He previously had nasal and palate surgeries and a Repose tongue suspension. His residual apnea hypopnea index (AHI) was 67. He had a dysphonia associated with a true vocal cord paralysis following resection of a benign neck mass in childhood. He also complained of inspiratory stridor with exercise and intolerance to continuous positive airway pressure. Physical examination revealed craniofacial hypoplasia, full base of tongue, and residual nasal airway obstruction. On laryngoscopy, the paretic aryepiglottic fold arytenoid complex prolapsed into the laryngeal inlet with each breath. This was more pronounced with greater respiratory effort. Surgical correction required a series of operations including awake tracheostomy, supraglottoplasty, midline glossectomy, genial tubercle advancement, maxillomandibular advancement, and reconstructive rhinoplasty. His final AHI was 1.9. Our patient's supraglottic laryngeal collapse constituted an area of obstruction not typically evaluated in OSA surgery. In conjunction with treating nasal, palatal, and hypopharyngeal subsites, our patient's supraglottoplasty represented a key component of his success. This case illustrates the need to evaluate the entire upper airway in a complicated case of OSA. PMID:22965285

  19. Methods of airway resistance assessment.

    PubMed

    Urbankowski, Tomasz; Przybyłowski, Tadeusz

    2016-01-01

    Airway resistance is the ratio of driving pressure to the rate of the airflow in the airways. The most frequent methods used to measure airway resistance are whole-body plethysmography, the interrupter technique and the forced oscillation technique. All these methods allow to measure resistance during respiration at the level close to tidal volume, they do not require forced breathing manoeuvres or deep breathing during measurement. The most popular method for measuring airway resistance is whole-body plethysmography. The results of plethysmography include among others the following parameters: airway resistance (Raw), airway conductance (Gaw), specific airway resistance (sRaw) and specific airway conductance (sGaw). The interrupter technique is based on the assumption that at the moment of airway occlusion, air pressure in the mouth is equal to the alveolar pressure . In the forced oscillation technique (FOT), airway resistance is calculated basing on the changes in pressure and flow caused by air vibration. The methods for measurement of airway resistance that are described in the present paper seem to be a useful alternative to the most common lung function test - spirometry. The target group in which these methods may be widely used are particularly the patients who are unable to perform spirometry.

  20. 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.

  1. Airway epithelial cell responses to ozone injury

    SciTech Connect

    Leikauf, G.D.; Simpson, L.G.; Zhao, Qiyu

    1995-03-01

    The airway epithelial cell is an important target in ozone injury. Once activated, the airway epithelium responds in three phases. The initial, or immediate phase, involves activation of constitutive cells, often through direct covalent interactions including the formation of secondary ozonolysis products-hydroxyhydroperoxides, aldehydes, and hydrogen peroxide. Recently, we found hydroxyhydroperoxides to be potent agonists; of bioactive eicosanoid formation by human airway epithelial cells in culture. Other probable immediate events include activation and inactivation of enzymes present on the epithelial surface (e.g., neutral endopeptidase). During the next 2 to 24 hr, or early phase, epithelial cells respond by synthesis and release of chemotactic factors, including chemokines-macrophage inflammatory protein-2, RANTES, and interleukin-8. Infiltrating leukocytes during this period also release elastase, an important agonist of epithelial cell mucus secretion and additional chemokine formation. The third (late) phase of ozone injury is characterized by eosinophil or monocyte infiltration. Cytokine expression leads to alteration of structural protein synthesis, with increases in fibronectin evident by in situ hybridization. Synthesis of epithelial antiproteases, e.g., secretary leukocyte protease inhibitor, may also increase locally 24 to 48 hr after elastase concentrations become excessive. Thus, the epithelium is not merely a passive barrier to ozone injury but has a dynamic role in directing the migration, activating, and then counteracting inflammatory cells. Through these complex interactions, epithelial cells can be viewed as the initiators (alpha) and the receptors (omega) of ozone-induced airway disease. 51 refs., 2 figs., 3 tabs.

  2. 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

  3. Managing upper airway obstruction.

    PubMed

    Innes, M H

    A complete respiratory obstruction can lead to death in 3 minutes. The first and constant duty of the nurse aider is to check that the person is breathing by looking, listening and feeling. Partial obstruction is no less serious than complete obstruction. The nurse aider, in any situation, should assess the problem and attempt to overcome the airway obstruction using the measures described. PMID:1490067

  4. Airway gene therapy.

    PubMed

    Davies, Jane C; Alton, Eric W F W

    2005-01-01

    Given both the accessibility and the genetic basis of several pulmonary diseases, the lungs and airways initially seemed ideal candidates for gene therapy. Several routes of access are available, many of which have been refined and optimized for nongene drug delivery. Two respiratory diseases, cystic fibrosis (CF) and alpha1-antitrypsin (alpha1-AT) deficiency, are relatively common; the single gene responsible has been identified and current treatment strategies are not curative. This type of inherited disease was the obvious initial target for gene therapy, but it has become clear that nongenetic and acquired diseases, including cancer, may also be amenable to this approach. The majority of preclinical and clinical studies in the airway have involved viral vectors, although for diseases such as CF, likely to require repeated application, non-viral delivery systems have clear advantages. However, with both approaches a range of barriers to gene expression have been identified that are limiting success in the airway and alveolar region. This chapter reviews these issues, strategies aimed at overcoming them, and progress into clinical trials with non-viral vectors in a variety of pulmonary diseases.

  5. Causes of the difficult airway.

    PubMed

    Orfanos, John G; Quereshy, Faisal A

    2010-03-01

    Recognizing a potentially difficult airway is important in avoiding a life-threatening emergency. There are 2 separate scenarios for considering the difficult airway: difficult mask ventilation (DMV) and difficult tracheal intubation (DTI). DMV can be described as lacking the ability to maintain oxygen saturation or lacking the ability to reverse signs of inadequate ventilation with positive-pressure mask ventilation under general anesthesia. DTI remains constant among anesthesia-related patient injuries, and is the third most common respiratory-related episode leading to death and possible brain damage. It is important to preoperatively assess every patient by completing a full history and physical. A thorough history can provide clues in detecting a possible difficult airway. Airway impairment has been further subdivided into the anatomic regions that affect the airway, namely above the larynx, supraglottic, glottic, subglottic, and tracheobronchial. This article discusses the factors that can result in a difficult airway.

  6. 17beta-Estradiol inhibits Ca2+-dependent homeostasis of airway surface liquid volume in human cystic fibrosis airway epithelia.

    PubMed

    Coakley, Ray D; Sun, Hengrui; Clunes, Lucy A; Rasmussen, Julia E; Stackhouse, James R; Okada, Seiko F; Fricks, Ingrid; Young, Steven L; Tarran, Robert

    2008-12-01

    Normal airways homeostatically regulate the volume of airway surface liquid (ASL) through both cAMP- and Ca2+-dependent regulation of ion and water transport. In cystic fibrosis (CF), a genetic defect causes a lack of cAMP-regulated CFTR activity, leading to diminished Cl- and water secretion from airway epithelial cells and subsequent mucus plugging, which serves as the focus for infections. Females with CF exhibit reduced survival compared with males with CF, although the mechanisms underlying this sex-related disadvantage are unknown. Despite the lack of CFTR, CF airways retain a limited capability to regulate ASL volume, as breathing-induced ATP release activates salvage purinergic pathways that raise intracellular Ca2+ concentration to stimulate an alternate pathway to Cl- secretion. We hypothesized that estrogen might affect this pathway by reducing the ability of airway epithelia to respond appropriately to nucleotides. We found that uridine triphosphate-mediated (UTP-mediated) Cl- secretion was reduced during the periovulatory estrogen maxima in both women with CF and normal, healthy women. Estrogen also inhibited Ca2+ signaling and ASL volume homeostasis in non-CF and CF airway epithelia by attenuating Ca2+ influx. This inhibition of Ca2+ signaling was prevented and even potentiated by estrogen antagonists such as tamoxifen, suggesting that antiestrogens may be beneficial in the treatment of CF lung disease because they increase Cl- secretion in the airways. PMID:19033671

  7. 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

    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.

  8. 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

  9. Reflex modulation of airflow dynamics through the upper airway.

    PubMed

    Seelagy, M M; Schwartz, A R; Russ, D B; King, E D; Wise, R A; Smith, P L

    1994-06-01

    We studied the effect of respiratory reflexes on maximal inspiratory flow (VImax) and its mechanical determinants, pharyngeal critical pressure (Pcrit) and nasal resistance, in an isolated feline upper airway preparation. Chemoreceptor reflexes were evaluated by varying inspired oxygen and end-tidal CO2 concentrations. At each gas concentration, we found that changes in VImax were related to changes in Pcrit. As CO2 increased, Pcrit became increasingly subatmospheric (P < 0.02), indicating reductions in pharyngeal collapsibility. In contrast, progressive hypoxia had no effect on Pcrit. We then examined the effects of vagal afferents and upper airway mucosal receptors on airflow dynamics at three levels of CO2. We confirmed that CO2 increased VImax (P < 0.01) and decreased Pcrit to more subatmospheric levels (P < 0.05) in both the presence and absence of vagal and airway mucosal afferent activity. Moreover, airway mucosal afferents led to smaller reductions in Pcrit (a less collapsible airway) (P < 0.05), whereas vagal afferents led to a larger increase in Pcrit (a more collapsible pharynx) under hypercapnic conditions (P < 0.01). We conclude that CO2 had a major effect on pharyngeal collapsability and that its effect was modulated by vagal and mucosal afferents. We speculate that the sensitivity and threshold to reflex CO2 responses play a major role in the maintenance of airway patency.

  10. 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

  11. 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

  12. 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.

  13. Loss of CFTR chloride channels alters salt absorption by cystic fibrosis airway epithelia in vitro.

    PubMed

    Zabner, J; Smith, J J; Karp, P H; Widdicombe, J H; Welsh, M J

    1998-09-01

    Cystic fibrosis (CF) is caused by the loss of functional CFTR Cl- channels. However, it is not understood how this defect disrupts salt and liquid movement in the airway or whether it alters the NaCl concentration in the thin liquid film covering the airway surface. Using a new approach, we found that CF airway surface liquid had a higher NaCl concentration than normal. Both CF and non-CF epithelia absorbed salt and liquid; however, expression of CFTR Cl- channels was required for maximal absorption. Thus, loss of CFTR elevates the salt concentration in CF airway surface liquid and in sweat by related mechanisms; the elevated NaCl concentration is due to a block in transcellular Cl- movement. The high NaCl may predispose CF airways to bacterial infections by inhibiting endogenous antibacterial defenses. PMID:9774978

  14. The buffer capacity of airway epithelial secretions

    PubMed Central

    Kim, Dusik; Liao, Jie; Hanrahan, John W.

    2014-01-01

    The pH of airway epithelial secretions influences bacterial killing and mucus properties and is reduced by acidic pollutants, gastric reflux, and respiratory diseases such as cystic fibrosis (CF). The effect of acute acid loads depends on buffer capacity, however the buffering of airway secretions has not been well characterized. In this work we develop a method for titrating micro-scale (30 μl) volumes and use it to study fluid secreted by the human airway epithelial cell line Calu-3, a widely used model for submucosal gland serous cells. Microtitration curves revealed that HCO−3 is the major buffer. Peak buffer capacity (β) increased from 17 to 28 mM/pH during forskolin stimulation, and was reduced by >50% in fluid secreted by cystic fibrosis transmembrane conductance regulator (CFTR)-deficient Calu-3 monolayers, confirming an important role of CFTR in HCO−3 secretion. Back-titration with NaOH revealed non-volatile buffer capacity due to proteins synthesized and released by the epithelial cells. Lysozyme and mucin concentrations were too low to buffer Calu-3 fluid significantly, however model titrations of porcine gastric mucins at concentrations near the sol-gel transition suggest that mucins may contribute to the buffer capacity of ASL in vivo. We conclude that CFTR-dependent HCO−3 secretion and epithelially-derived proteins are the predominant buffers in Calu-3 secretions. PMID:24917822

  15. A comparison between the impact of two types of dietary protein on brain glucose concentrations and oxidative stress in high fructose-induced metabolic syndrome rats

    PubMed Central

    MADANI, ZOHRA; MALAISSE, WILLY J.; AIT-YAHIA, DALILA

    2015-01-01

    The present study explored the potential of fish proteins to counteract high glucose levels and oxidative stress induced by fructose in the brain. A total of 24 male Wistar rats consumed sardine protein or casein with or without high fructose (64%). After 2 months, brain tissue was used for analyses. The fructose rats exhibited an increase in body mass index (BMI), body weight, absolute and relative brain weights and brain glucose; however, there was a decrease in food and water intake. Fructose disrupts membrane homeostasis, as evidenced by an increase in the brain hydroperoxides and a decrease in catalase (CAT) and glutathione peroxidase (GSH-Px) compared to the control. The exposure to the sardine protein reduced BMI, food intake, glucose and hydroperoxides, and increased CAT and GSH-Px in the brain. In conclusion, the metabolic dysfunctions associated with the fructose treatment were ameliorated by the presence of sardine protein in the diet by decreasing BMI, brain glucose and lipid peroxidation, and increasing CAT and GSH-Px activities. PMID:26405554

  16. Activation of protein kinase C by elevation of glucose concentration: Proposal for a mechanism in the development of diabetic vascular complications

    SciTech Connect

    Lee, Tianshing; Saltsman, K.A.; Ohashi, Hiromi; King, G.L. )

    1989-07-01

    Hyperglycemia is believed to be the major cause of diabetic vascular complications involving both microvessels and arteries as in the retina, renal glomeruli, and aorta. It is unclear by which mechanism hyperglycemia is altering the metabolism and functions of vascular cells, although changes in nonenzymatic protein glycosylation and increases in cellular sorbitol levels have been postulated to be involved. Previously, the authors have reported that the elevation of extracellular glucose levels with cultured bovine retinal capillary endothelial cells causes an increase in protein kinase C (PKC) activity of the membranous pool with a parallel decrease in the cytosol without alteration of its total activity. Now they demonstrate that the mechanism for the activation of PKC is due to an enhanced de novo synthesis of diacylglycerol as indicated by a 2-fold increase of ({sup 14}C)diacylglycerol labeling from ({sup 14}C)glucose. The elevated diacylglycerol de novo synthesis is secondarily due to increased formation of precursors derived from glucose metabolism; this formation is enhanced by hyperglycemia as substantiated by elevated ({sup 3}H)glucose conversion into water. This effect of hyperglycemia on PKC is also observed in cultured aortic smooth muscle and endothelial cells and the retina and kidney of diabetic rats, but not in the brain. Since PKC in vascular cells has been shown to modulate hormone receptor turnover, neovascularization in vitro, and cell growth, they propose that this mechanism of enhancing the membranous PKC activities by hyperglycemia plays an important role in the development of diabetic vascular complications.

  17. Specific natural isotope profile studied by isotope ratio mass spectrometry (SNIP-IRMS): (13)C/(12)C ratios of fructose, glucose, and sucrose for improved detection of sugar addition to pineapple juices and concentrates.

    PubMed

    González, J; Remaud, G; Jamin, E; Naulet, N; Martin, G G

    1999-06-01

    The delta(13)C values of fructose, glucose, and sucrose have been determined in authentic pineapple juices. The sugar fraction is separated from the organic acids by an anionic exchange process. Then the individual components (fructose, glucose, and sucrose) are isolated on a preparative HPLC device using a NH(2)-type column. It is demonstrated that no significant isotope fractionation occurs when close to 100% of material is recovered and when the hydrolysis of sucrose is avoided. The control of the recovery rates and of the sucrose hydrolysis rate after purification is recommended for a reliable interpretation of the results. Correlations between the delta(13)C values of fructose (delta(13)Cf), glucose (delta(13)Cg), and sucrose (delta(13)Csu) can be characterized by systematic differences between these values. For the set of measurements on authentic pineapple juices and concentrates, the mean and the standard deviation of the differences are delta(13)Cf - delta(13)Cg = -0.6 +/- 0.6 per thousand, delta(13)Cf - delta(13)Csu = -1.3 +/- 0. 6 per thousand, and delta(13)Cf - delta(13)Csu = -0.7 +/- 0.5 per thousand. The determinations of the (13)C content of fructose, glucose, and sucrose enable a refinement of the detection of added sugars in fruit juices, re-enforcing the SNIP-IRMS method. PMID:10794628

  18. Airway-parenchymal interdependence after airway contraction in rat lung explants.

    PubMed

    Adler, A; Cowley, E A; Bates, J H; Eidelman, D H

    1998-07-01

    The constriction of pulmonary airways is limited by the tethering effect exerted by parenchymal attachments. To characterize this tethering effect at the scale of intraparenchymal airways, we studied the pattern of parenchymal distortion due to bronchoconstriction in a rat lung explant system. First, we measured the elastic modulus under tension for 2% (wt/vol) agarose alone (37.6 +/- 1.5 kPa) and for agarose-filled lung (5.7 +/- 1.3 kPa). The latter is similar to the elastic modulus of air-filled lung at total lung capacity (4.5-6 kPa) (S. J. Lai-Fook, T. A. Wilson, R. E. Hyatt, and J. R. Rodarte. J. Appl. Physiol. 40: 508-513, 1976), suggesting that explants can be used as a model of lung tissue distortion. Subsequently, confocal microscopic images of fluorescently labeled 0.5-mm-thick explants prepared from agarose-filled rat lungs inflated to total lung capacity (48 ml/kg) were acquired. Images were taken before and after airway constriction was induced by direct application of 10 mM methacholine, and the pattern of parenchymal distortion was measured from the displacement of tissue landmarks identified in each image for 14 explants. The magnitude of the radial component of tissue displacement was calculated as a function of distance from the airway wall and characterized by a parameter, b, describing the rate at which tissue movement decreased with radial distance. The parameter b was 0.994 +/- 0.19 (SE), which is close to the prediction of b = 1 of micromechanical modeling (T. A. Wilson. J. Appl. Physiol. 33: 472-478, 1972). There was significant variability in b, however, which was correlated with the fractional reduction in airway diameter (r = 0.496). Additionally, parenchymal distortion showed significant torsion with respect to the radial direction. This torsion was similar in concentric zones around the airway, suggesting that it originates from inhomogeneity in the parenchyma rather than inhomogeneous airway constriction. Our results demonstrate the

  19. IL-6 trans-signaling increases expression of airways disease genes in airway smooth muscle

    PubMed Central

    Robinson, Mac B.; Deshpande, Deepak A.; Chou, Jeffery; Cui, Wei; Smith, Shelly; Langefeld, Carl; Hastie, Annette T.; Bleecker, Eugene R.

    2015-01-01

    Genetic data suggest that IL-6 trans-signaling may have a pathogenic role in the lung; however, the effects of IL-6 trans-signaling on lung effector cells have not been investigated. In this study, human airway smooth muscle (HASM) cells were treated with IL-6 (classical) or IL-6+sIL6R (trans-signaling) for 24 h and gene expression was measured by RNAseq. Intracellular signaling and transcription factor activation were assessed by Western blotting and luciferase assay, respectively. The functional effect of IL-6 trans-signaling was determined by proliferation assay. IL-6 trans-signaling had no effect on phosphoinositide-3 kinase and Erk MAP kinase pathways in HASM cells. Both classical and IL-6 trans-signaling in HASM involves activation of Stat3. However, the kinetics of Stat3 phosphorylation by IL-6 trans-signaling was different than classical IL-6 signaling. This was further reflected in the differential gene expression profile by IL-6 trans-signaling in HASM cells. Under IL-6 trans-signaling conditions 36 genes were upregulated, including PLA2G2A, IL13RA1, MUC1, and SOD2. Four genes, including CCL11, were downregulated at least twofold. The expression of 112 genes was divergent between IL-6 classical and trans-signaling, including the genes HILPDA, NNMT, DAB2, MUC1, WWC1, and VEGFA. Pathway analysis revealed that IL-6 trans-signaling induced expression of genes involved in regulation of airway remodeling, immune response, hypoxia, and glucose metabolism. Treatment of HASM cells with IL-6+sIL6R induced proliferation in a dose-dependent fashion, suggesting a role for IL-6 trans-signaling in asthma pathogenesis. These novel findings demonstrate differential effect of IL-6 trans-signaling on airway cells and identify IL-6 trans-signaling as a potential modifier of airway inflammation and remodeling. PMID:26001777

  20. 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.

  1. The mechanics of airway closure.

    PubMed

    Heil, Matthias; Hazel, Andrew L; Smith, Jaclyn A

    2008-11-30

    We describe how surface-tension-driven instabilities of the lung's liquid lining may lead to pulmonary airway closure via the formation of liquid bridges that occlude the airway lumen. Using simple theoretical models, we demonstrate that this process may occur via a purely fluid-mechanical "film collapse" or through a coupled, fluid-elastic "compliant collapse" mechanism. Both mechanisms can lead to airway closure in times comparable with the breathing cycle, suggesting that surface tension is the primary mechanical effect responsible for the closure observed in peripheral regions of the human lungs. We conclude by discussing the influence of additional effects not included in the simple models, such as gravity, the presence of pulmonary surfactant, respiratory flow and wall motion, the airways' geometry, and the mechanical structure of the airway walls. PMID:18595784

  2. 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

  3. Assessment of airway inflammation by exhaled breath condensate and impedance due to gastroesophageal reflux disease (GERD).

    PubMed

    Shimizu, Yasuo; Dobashi, Kunio; Nagoshi, Atsuto; Kawamura, Osamu; Mori, Masatomo

    2009-09-01

    Avoiding oxidative stress in the airways is important for the treatment of respiratory disease associated with gastroesophageal reflux disease (GERD). It is often difficult to decide whether GERD is causing airway inflammation or whether an airway disease is complicated by GERD. Measurement of exhaled breath condensate (EBC) is performed by cooling and collecting the airway lining fluid contained in exhaled air. A decrease of pH and an increase of the 8-isoprostane concentration in EBC have been observed in patients with mild to moderate asthma accompanied by GERD. There are still problems to be overcome before EBC can be used clinically, but pH and 8-isoprostane may be promising objective markers of airway inflammation due to GERD. The disease concept and diagnosis of GERD are constantly advancing, including the development of impedance methods. It is expected that treatment will be based on the latest diagnostic knowledge of GERD associated with respiratory disease and on monitoring of airway inflammation.

  4. Increased airway epithelial Na+ absorption produces cystic fibrosis-like lung disease in mice.

    PubMed

    Mall, Marcus; Grubb, Barbara R; Harkema, Jack R; O'Neal, Wanda K; Boucher, Richard C

    2004-05-01

    Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene result in defective epithelial cAMP-dependent Cl(-) secretion and increased airway Na(+) absorption. The mechanistic links between these altered ion transport processes and the pathogenesis of cystic fibrosis lung disease, however, are unclear. To test the hypothesis that accelerated Na(+) transport alone can produce cystic fibrosis-like lung disease, we generated mice with airway-specific overexpression of epithelial Na(+) channels (ENaC). Here we show that increased airway Na(+) absorption in vivo caused airway surface liquid (ASL) volume depletion, increased mucus concentration, delayed mucus transport and mucus adhesion to airway surfaces. Defective mucus transport caused a severe spontaneous lung disease sharing features with cystic fibrosis, including mucus obstruction, goblet cell metaplasia, neutrophilic inflammation and poor bacterial clearance. We conclude that increasing airway Na(+) absorption initiates cystic fibrosis-like lung disease and produces a model for the study of the pathogenesis and therapy of this disease. PMID:15077107

  5. 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.

  6. Ultrafine carbon black particles cause early airway inflammation and have adjuvant activity in a mouse allergic airway disease model.

    PubMed

    de Haar, Colin; Hassing, Ine; Bol, Marianne; Bleumink, Rob; Pieters, Raymond

    2005-10-01

    To gain more insight into the mechanisms of particulate matter (PM)-induced adjuvant activity, we studied the kinetics of airway toxicity/inflammation and allergic sensitization to ovalbumin (OVA) in response to ultrafine carbon black particles (CBP). Mice were exposed intranasally to OVA alone or in combination with different concentrations of CBP. Airway toxicity and inflammation were assessed at days 4 and 8. Immune adjuvant effects were studied in the lung draining peribronchial lymph nodes (PBLN) at day 8. Antigen-specific IgE was measured at days 21 and 28, whereas allergic airway inflammation was studied after OVA challenges (day 28). Results show that a total dose of 200 microg CBP per mouse, but not 20 microg or 2 microg, induced immediate airway inflammation. This 200 microg CBP was the only dose that had immune adjuvant activity, by inducing enlargement of the PBLN and increasing OVA-specific production of Th2 cytokines (IL-4, IL-5, and IL-10). The immune adjuvant activity of 200 microg CBP dosing was further examined. Whereas increased OVA-specific IgE levels in serum on day 21 confirms systemic sensitization, this was further supported by allergic airway inflammation after challenges with OVA. Our data show a link between early airway toxicity and adjuvant effects of CBP. In addition, results indicate that local cytokine production early after exposure to CBP is predictive of allergic airway inflammation. In addition this model appears suitable for studying the role of airway toxicity, inflammation and other mechanisms of particle adjuvant activity, and predicting the adjuvant potential of different particles.

  7. 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

  8. 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.

  9. Glucose control.

    PubMed

    Preiser, Jean-Charles

    2013-01-01

    Stress-related hyperglycemia is a common finding in acutely ill patients, and is related to the severity and outcome of the critical illness. The pathophysiology of stress hyperglycemia includes hormonal and neural signals, leading to increased production of glucose by the liver and peripheral insulin resistance mediated by the translocation of transmembrane glucose transporters. In one pioneering study, tight glycemic control by intensive insulin therapy in critically ill patients was associated with improved survival. However, this major finding was not confirmed in several other prospective randomized controlled trials. The reasons underlying the discrepancy between the first and the subsequent studies could include nutritional strategy (amount of calories provided, use of parenteral nutrition), case-mix, potential differences in the optimal blood glucose level (BG) in different types of patients, hypoglycemia and its correction, and the magnitude of glucose variability. Therefore, an improved understanding of the physiology and pathophysiology of glycemic regulation during acute illness is needed. Safe and effective glucose control will need improvement in the definition of optimal BG and in the measurement techniques, perhaps including continuous monitoring of insulin algorithms and closed-loop systems. PMID:23075589

  10. Glucose-stat, a glucose-controlled continuous culture.

    PubMed Central

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

    1991-01-01

    A predictive and feedback proportional control algorithm, developed for fed-batch fermentations and described in a companion paper (G. L. Kleman, J. J. Chalmers, G. W. Luli, and W. R. Strohl, Appl. Environ. Microbiol. 57:910-917, 1991), was used in this work to control a continuous culture on the basis of the soluble-glucose concentration (called the glucose-stat). This glucose-controlled continuous-culture system was found to reach and maintain steady state for 11 to 24 residence times when four different background glucose concentrations (0.27, 0.50, 0.7, and 1.5 g/liter) were used. The predictive-plus-feedback control system yielded very tight control of the continuous nutristat cultures; glucose concentrations were maintained at the set points with less than 0.003 standard error. Acetate production by Escherichia coli B in glucose-stats was found not to be correlated with the level of steady-state soluble-glucose concentration. PMID:2059050

  11. Glucose-stat, a glucose-controlled continuous culture.

    PubMed

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

    1991-04-01

    A predictive and feedback proportional control algorithm, developed for fed-batch fermentations and described in a companion paper (G. L. Kleman, J. J. Chalmers, G. W. Luli, and W. R. Strohl, Appl. Environ. Microbiol. 57:910-917, 1991), was used in this work to control a continuous culture on the basis of the soluble-glucose concentration (called the glucose-stat). This glucose-controlled continuous-culture system was found to reach and maintain steady state for 11 to 24 residence times when four different background glucose concentrations (0.27, 0.50, 0.7, and 1.5 g/liter) were used. The predictive-plus-feedback control system yielded very tight control of the continuous nutristat cultures; glucose concentrations were maintained at the set points with less than 0.003 standard error. Acetate production by Escherichia coli B in glucose-stats was found not to be correlated with the level of steady-state soluble-glucose concentration. PMID:2059050

  12. 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

  13. 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

  14. 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

  15. Airway Surface Mycosis in Chronic Th2-Associated Airway Disease

    PubMed Central

    Porter, Paul; Lim, Dae Jun; Maskatia, Zahida Khan; Mak, Garbo; Tsai, Chu-Lin; Citardi, Martin J; Fakhri, Samer; Shaw, Joanne L.; Fothergil, Annette; Kheradmand, Farrah; Corry, David B; Luong, Amber

    2014-01-01

    Background Environmental fungi have been linked to T helper type 2 (Th2) cell-related airway inflammation and the Th2-associated chronic airway diseases asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and allergic fungal rhinosinusitis (AFRS), but whether these organisms participate directly or indirectly in disease pathology remains unknown. Objective To determine the frequency of fungus isolation and fungus-specific immunity in Th2-associated and non-associated airway disease patients. Methods Sinus lavage fluid and blood were collected from sinus surgery patients (n=118) including CRS patients with and without nasal polyps and AFRS and non-CRS/non-asthmatic control patients. Asthma status was deteremined from medical history. Sinus lavage fluids were cultured and directly examined for evidence of viable fungi. Peripheral blood mononuclear cells were restimulated with fungal antigens in an enzyme linked immunocell spot (ELISpot) assay to determine total memory fungus-specific IL-4-secreting cells. These data were compared to fungus-specific IgE levels measured from plasma by ELISA. Results Filamentous fungi were significantly more commonly cultured from Th2-associated airway disease subjects (asthma, CRSwNP, or AFRS: n=68) compared to non-Th2-associated control patients (n=31); 74% vs 16% respectively, p<0.001. Both fungus-specific IL-4 ELISpot (n=48) and specific IgE (n=70) data correlated with Th2-associated diseases (sensitivity 73% and specificity 100% vs. 50% and 77%, respectively). Conclusions The frequent isolation of fungi growing directly within the airways accompanied by specific immunity to these organisms only in patients with Th2-associated chronic airway diseases suggests that fungi participate directly in the pathogenesis of these conditions. Efforts to eradicate airway fungi from the airways should be considered in selected patients. Clinical Implications Airway fungi may contribute to the expression of sinusitis with nasal polyps and

  16. [Effects of once-daily low-dose administration of sustained-release theophylline on airway inflammation and airway hyperresponsiveness in patients with asthma].

    PubMed

    Terao, Ichiro

    2002-04-01

    Bronchial asthma is eosinophilic airway inflammation with enhanced airway responsiveness induced by eosinophilic granule proteins such as eosinophilic cationic protein (ECP) that are released from eosinophils. In the present study using 30 outpatients with mild to moderate asthma who had no history of treatment with steroid inhalation, we examined the effects of 4-week low-dose (200 mg/day) treatment with Uniphyl Tablets, a sustained-release theophylline formulated for once-daily dosing, on airway inflammation and airway hyperresponsiveness, as well as on respiratory function. Uniphyl Tablets significantly (p < 0.01) decreased peripheral blood eosinophil count from 647.00 to 444.17/mm3 and ECP level (geometric mean) from 1318 to 741 ng/ml and improved airway hyperresponsiveness as indicated by a decrease in airway hyperresponsiveness (Dmin, geometric mean) from 1.15 to 6.70 units. FEV1.0 and PEF showed statistically significant (p < 0.01) improvement from 2.39 to 2.69 L and from 6.21 to 7.14 L/sec, respectively. V25 and V50 also showed statistically significant (p < 0.05) improvement. Mean blood theophylline concentration at the time the improvements were seen was 3.95 mg/mL. These results suggest that low-dose administration of Uniphyl Tablets has anti-airway inflammatory and anti-airway hyperresponsiveness effects in mild to moderate asthmatic patients.

  17. Blood-Brain Glucose Transfer: Repression in Chronic Hyperglycemia

    NASA Astrophysics Data System (ADS)

    Gjedde, Albert; Crone, Christian

    1981-10-01

    Diabetic patients with increased plasma glucose concentrations may develop cerebral symptoms of hypoglycemia when their plasma glucose is rapidly lowered to normal concentrations. The symptoms may indicate insufficient transport of glucose from blood to brain. In rats with chronic hyperglycemia the maximum glucose transport capacity of the blood-brain barrier decreased from 400 to 290 micromoles per 100 grams per minute. When plasma glucose was lowered to normal values, the glucose transport rate into brain was 20 percent below normal. This suggests that repressive changes of the glucose transport mechanism occur in brain endothelial cells in response to increased plasma glucose.

  18. Airway obstruction with cricoid pressure.

    PubMed

    Hartsilver, E L; Vanner, R G

    2000-03-01

    Cricoid pressure may cause airway obstruction. We investigated whether this is related to the force applied and to the technique of application. We recorded expired tidal volumes and inflation pressures during ventilation via a face-mask and oral airway in 52 female patients who were anaesthetised and about to undergo elective surgery. An inspired tidal volume of 900 ml was delivered using a ventilator. Ventilation was assessed under five different conditions: no cricoid pressure, backwards cricoid pressure applied with a force of 30 N, cricoid pressure applied in an upward and backward direction with a force of 30 N, backwards cricoid pressure with a force of 44 N and through a tracheal tube. An expired tidal volume of < 200 ml was taken to indicate airway obstruction. Airway obstruction did not occur without cricoid pressure, but did occur in one patient (2%) with cricoid pressure at 30 N, in 29 patients (56%) with 30 N applied in an upward and backward direction and in 18 (35%) patients with cricoid pressure at 44 N. Cricoid pressure applied with a force of 44 N can cause airway obstruction but if cricoid pressure is applied with a force of 30 N, airway obstruction occurs less frequently (p = 0.0001) unless the force is applied in an upward and backward direction.

  19. 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

  20. Airway obstruction with cricoid pressure.

    PubMed

    Hartsilver, E L; Vanner, R G

    2000-03-01

    Cricoid pressure may cause airway obstruction. We investigated whether this is related to the force applied and to the technique of application. We recorded expired tidal volumes and inflation pressures during ventilation via a face-mask and oral airway in 52 female patients who were anaesthetised and about to undergo elective surgery. An inspired tidal volume of 900 ml was delivered using a ventilator. Ventilation was assessed under five different conditions: no cricoid pressure, backwards cricoid pressure applied with a force of 30 N, cricoid pressure applied in an upward and backward direction with a force of 30 N, backwards cricoid pressure with a force of 44 N and through a tracheal tube. An expired tidal volume of < 200 ml was taken to indicate airway obstruction. Airway obstruction did not occur without cricoid pressure, but did occur in one patient (2%) with cricoid pressure at 30 N, in 29 patients (56%) with 30 N applied in an upward and backward direction and in 18 (35%) patients with cricoid pressure at 44 N. Cricoid pressure applied with a force of 44 N can cause airway obstruction but if cricoid pressure is applied with a force of 30 N, airway obstruction occurs less frequently (p = 0.0001) unless the force is applied in an upward and backward direction. PMID:10671836

  1. Antigen Sensitization Influences Organophosphorus Pesticide–Induced Airway Hyperreactivity

    PubMed Central

    Proskocil, Becky J.; Bruun, Donald A.; Lorton, Jesse K.; Blensly, Kirsten C.; Jacoby, David B.; Lein, Pamela J.; Fryer, Allison D.

    2008-01-01

    Background Recent epidemiologic studies have identified organophosphorus pesticides (OPs) as environmental factors potentially contributing to the increase in asthma prevalence over the last 25 years. In support of this hypothesis, we have demonstrated that environmentally relevant concentrations of OPs induce airway hyperreactivity in guinea pigs. Objectives Sensitization to allergen is a significant contributing factor in asthma, and we have shown that sensitization changes virus-induced airway hyperreactivity from an eosinophil-independent mechanism to one mediated by eosinophils. Here, we determine whether sensitization similarly influences OP-induced airway hyperreactivity. Methods Nonsensitized and ovalbumin-sensitized guinea pigs were injected subcutaneously with the OP parathion (0.001–1.0 mg/kg). Twenty-four hours later, animals were anesthetized and ventilated, and bronchoconstriction was measured in response to either vagal stimulation or intravenous acetylcholine. Inflammatory cells and acetylcholinesterase activity were assessed in tissues collected immediately after physiologic measurements. Results Ovalbumin sensitization decreased the threshold dose for parathion-induced airway hyperreactivity and exacerbated parathion effects on vagally induced bronchoconstriction. Pretreatment with antibody to interleukin (IL)-5 prevented parathion-induced hyperreactivity in sensitized but not in nonsensitized guinea pigs. Parathion did not increase the number of eosinophils in airways or the number of eosinophils associated with airway nerves nor did it alter eosinophil activation as assessed by major basic protein deposition. Conclusions Antigen sensitization increases vulnerability to parathion-induced airway hyperreactivity and changes the mechanism to one that is dependent on IL-5. Because sensitization to allergens is characteristic of 50% of the general population and 80% of asthmatics (including children), these findings have significant implications for

  2. Fast-induced changes in plasma glucose, insulin and free fatty acid concentration compared in rats during the night and day.

    PubMed

    Larue-Achagiotis, C; Le Magnen, J

    1983-01-01

    Changes in PG, PI and PFFA were examined and compared in fed rats or after 0 to 12 hours of fasting, during the night or during the day. At night, a progressive decrease in PG and PI and an increase in PFFA were induced by 0 to 12 hours of food deprivation. During the light period a decrease in PG occurred only from the 6th hour of fasting. A slight, progressive increase in PFFA levels was induced from 0 to 12 hours of fasting, while no significant variation of PI levels was observed. The results are discussed in terms of relationships between blood glucose, PFFA levels, and food intake in control rats over the circadian cycle.

  3. Intravenous glucose administration in fasting rats has differential effects on acylated and unacylated ghrelin in the portal and systemic circulation: a comparison between portal and peripheral concentrations in anesthetized rats.

    PubMed

    Gauna, Carlotta; Uitterlinden, Piet; Kramer, Piet; Kiewiet, Rosalie M; Janssen, Joop A M J L; Delhanty, Patric J D; van Aken, Maarten O; Ghigo, Ezio; Hofland, Leo J; Themmen, Axel P N; van der Lely, Aart Jan

    2007-11-01

    Ghrelin is produced by the gastrointestinal tract, and its systemic concentrations are mainly regulated by nutritional factors. Our aim was to investigate: 1) endogenous portal and systemic acylated and unacylated ghrelin levels (AG and UAG, respectively); 2) whether an iv glucose tolerance test (IVGTT) modifies AG and UAG; and 3) whether the liver passage plays a role in regulating systemic AG and UAG. To elucidate this, we evaluated the effects of IVGTT or saline injection on endogenous portal and systemic concentrations of glucose, insulin, AG, and UAG in anesthetized fasting rats. Hepatic extraction of insulin, AG, and UAG and the ratio of AG to UAG were also measured. IVGTT suppressed both portal (P < 0.03) and peripheral (P < 0.05) UAG, whereas it only blunted prehepatic, but not peripheral, AG. During fasting, hepatic clearance of UAG was 11%, and it was decreased to 8% by IVGTT. AG was cleared by the liver by 38% but unaffected by glucose. The AG to UAG ratio was higher in the portal than the systemic circulation, both in the saline (P < 0.004) and IVGTT (P < 0.0005) rats. In conclusion, this study shows that: 1) the ratio of AG to UAG is very low in the portal vein and decreases further in the systemic circulation; 2) IVGTT in anesthetized fasting rats inhibits UAG, whereas it only blunts prehepatic, but not systemic, AG; and 3) hepatic clearance of AG is much higher than that of UAG. Thus, our results suggest that peripheral AG metabolic regulation and action are mainly confined within the gastrointestinal tract.

  4. 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

  5. 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

  6. 21 CFR 168.120 - Glucose sirup.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Glucose sirup. 168.120 Section 168.120 Food and... § 168.120 Glucose sirup. (a) Glucose sirup is the purified, concentrated, aqueous solution of nutritive... equivalent), expressed as D-glucose, is not less than 20.0 percent m/m calculated on a dry basis. (2)...

  7. 21 CFR 168.120 - Glucose sirup.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Glucose sirup. 168.120 Section 168.120 Food and... § 168.120 Glucose sirup. (a) Glucose sirup is the purified, concentrated, aqueous solution of nutritive... equivalent), expressed as D-glucose, is not less than 20.0 percent m/m calculated on a dry basis. (2)...

  8. 21 CFR 168.120 - Glucose sirup.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Glucose sirup. 168.120 Section 168.120 Food and... § 168.120 Glucose sirup. (a) Glucose sirup is the purified, concentrated, aqueous solution of nutritive... equivalent), expressed as D-glucose, is not less than 20.0 percent m/m calculated on a dry basis. (2)...

  9. 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

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

    PubMed

    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. PMID:23956499

  11. 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.

  12. Effects of pentobarbital on upper airway patency during sleep

    PubMed Central

    Eikermann, M.; Eckert, D.J.; Chamberlin, N.L.; Jordan, A.S.; Zaremba, S.; Smith, S.; Rosow, C.; Malhotra, A.

    2012-01-01

    We hypothesised that pentobarbital would improve upper airway mechanics based on an increase in latency to arousal and amplitude of the phasic genioglossus electromyogram (EMG), and a decrease in the active upper airway critical closing pressure (Pcrit). 12 healthy subjects received pentobarbital (100 mg) or placebo in a double-blind, crossover protocol. During wakefulness, we measured the genioglossus reflex response to negative pressure pulses. During sleep, carbon dioxide was insufflated into the inspired air. Airway pressure was then decreased in a stepwise fashion until arousal from sleep. With basal breathing during sleep: flow rate was lower in volunteers given pentobarbital; end-tidal CO2 concentration and upper airway resistance were greater; and Pcrit was unaffected (pentobarbital mean±sd -11.7±4.5 versus placebo -10.25±3.6 cmH2O; p=0.11). Pentobarbital increased the time to arousal (297±63s versus 232±67 s; p<0.05), at which time phasic genioglossus EMG was higher (6.2±4.8% maximal versus 3.1±3%; p<0.05) as were CO2 levels. The increase in genioglossus EMG after CO2 administration was greater after pentobarbital versus placebo. Pentobarbital did not affect the genioglossus negative-pressure reflex. Pentobarbital increases the time to arousal and stimulates genioglossus muscle activity, but it also increases upper airway resistance during sleep. PMID:20032012

  13. Effects of pentobarbital on upper airway patency during sleep.

    PubMed

    Eikermann, M; Eckert, D J; Chamberlin, N L; Jordan, A S; Zaremba, S; Smith, S; Rosow, C; Malhotra, A

    2010-09-01

    We hypothesised that pentobarbital would improve upper airway mechanics based on an increase in latency to arousal and amplitude of the phasic genioglossus electromyogram (EMG), and a decrease in the active upper airway critical closing pressure (P(crit)). 12 healthy subjects received pentobarbital (100 mg) or placebo in a double-blind, crossover protocol. During wakefulness, we measured the genioglossus reflex response to negative pressure pulses. During sleep, carbon dioxide was insufflated into the inspired air. Airway pressure was then decreased in a stepwise fashion until arousal from sleep. With basal breathing during sleep: flow rate was lower in volunteers given pentobarbital; end-tidal CO(2) concentration and upper airway resistance were greater; and P(crit) was unaffected (pentobarbital mean ± SD -11.7 ± 4.5 versus placebo -10.25 ± 3.6 cmH(2)O; p = 0.11). Pentobarbital increased the time to arousal (297 ± 63s versus 232 ± 67 s; p<0.05), at which time phasic genioglossus EMG was higher (6.2 ± 4.8% maximal versus 3.1 ± 3%; p<0.05) as were CO(2) levels. The increase in genioglossus EMG after CO(2) administration was greater after pentobarbital versus placebo. Pentobarbital did not affect the genioglossus negative-pressure reflex. Pentobarbital increases the time to arousal and stimulates genioglossus muscle activity, but it also increases upper airway resistance during sleep.

  14. A MEMS Dielectric Affinity Glucose Biosensor

    PubMed Central

    Huang, Xian; Li, Siqi; Davis, Erin; Li, Dachao; Wang, Qian; Lin, Qiao

    2013-01-01

    Continuous glucose monitoring (CGM) sensors based on affinity detection are desirable for long-term and stable glucose management. However, most affinity sensors contain mechanical moving structures and complex design in sensor actuation and signal readout, limiting their reliability in subcutaneously implantable glucose detection. We have previously demonstrated a proof-of-concept dielectric glucose sensor that measured pre-mixed glucose-sensitive polymer solutions at various glucose concentrations. This sensor features simplicity in sensor design, and possesses high specificity and accuracy in glucose detection. However, lack of glucose diffusion passage, this device is unable to fulfill real-time in-vivo monitoring. As a major improvement to this device, we present in this paper a fully implantable MEMS dielectric affinity glucose biosensor that contains a perforated electrode embedded in a suspended diaphragm. This capacitive-based sensor contains no moving parts, and enables glucose diffusion and real-time monitoring. The experimental results indicate that this sensor can detect glucose solutions at physiological concentrations and possesses good reversibility and reliability. This sensor has a time constant to glucose concentration change at approximately 3 min, which is comparable to commercial systems. The sensor has potential applications in fully implantable CGM that require excellent long-term stability and reliability. PMID:24511215

  15. Glucose-sensing neurons of the hypothalamus

    PubMed Central

    Burdakov, Denis; Luckman, Simon M; Verkhratsky, Alexei

    2005-01-01

    Specialized subgroups of hypothalamic neurons exhibit specific excitatory or inhibitory electrical responses to changes in extracellular levels of glucose. Glucose-excited neurons were traditionally assumed to employ a ‘β-cell’ glucose-sensing strategy, where glucose elevates cytosolic ATP, which closes KATP channels containing Kir6.2 subunits, causing depolarization and increased excitability. Recent findings indicate that although elements of this canonical model are functional in some hypothalamic cells, this pathway is not universally essential for excitation of glucose-sensing neurons by glucose. Thus glucose-induced excitation of arcuate nucleus neurons was recently reported in mice lacking Kir6.2, and no significant increases in cytosolic ATP levels could be detected in hypothalamic neurons after changes in extracellular glucose. Possible alternative glucose-sensing strategies include electrogenic glucose entry, glucose-induced release of glial lactate, and extracellular glucose receptors. Glucose-induced electrical inhibition is much less understood than excitation, and has been proposed to involve reduction in the depolarizing activity of the Na+/K+ pump, or activation of a hyperpolarizing Cl− current. Investigations of neurotransmitter identities of glucose-sensing neurons are beginning to provide detailed information about their physiological roles. In the mouse lateral hypothalamus, orexin/hypocretin neurons (which promote wakefulness, locomotor activity and foraging) are glucose-inhibited, whereas melanin-concentrating hormone neurons (which promote sleep and energy conservation) are glucose-excited. In the hypothalamic arcuate nucleus, excitatory actions of glucose on anorexigenic POMC neurons in mice have been reported, while the appetite-promoting NPY neurons may be directly inhibited by glucose. These results stress the fundamental importance of hypothalamic glucose-sensing neurons in orchestrating sleep-wake cycles, energy expenditure and

  16. Allergen-induced airway responses.

    PubMed

    Gauvreau, Gail M; El-Gammal, Amani I; O'Byrne, Paul M

    2015-09-01

    Environmental allergens are an important cause of asthma and can contribute to loss of asthma control and exacerbations. Allergen inhalation challenge has been a useful clinical model to examine the mechanisms of allergen-induced airway responses and inflammation. Allergen bronchoconstrictor responses are the early response, which reaches a maximum within 30 min and resolves by 1-3 h, and late responses, when bronchoconstriction recurs after 3-4 h and reaches a maximum over 6-12 h. Late responses are followed by an increase in airway hyperresponsiveness. These responses occur when IgE on mast cells is cross-linked by an allergen, causing degranulation and the release of histamine, neutral proteases and chemotactic factors, and the production of newly formed mediators, such as cysteinyl leukotrienes and prostaglandin D2. Allergen-induced airway inflammation consists of an increase in airway eosinophils, basophils and, less consistently, neutrophils. These responses are mediated by the trafficking and activation of myeloid dendritic cells into the airways, probably as a result of the release of epithelial cell-derived thymic stromal lymphopoietin, and the release of pro-inflammatory cytokines from type 2 helper T-cells. Allergen inhalation challenge has also been a widely used model to study potential new therapies for asthma and has an excellent negative predictive value for this purpose. PMID:26206871

  17. 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

  18. 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

    2016-03-01

    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.

  19. 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.

  20. Composition of nasal airway surface liquid in cystic fibrosis and other airway diseases determined by X-ray microanalysis.

    PubMed

    Vanthanouvong, V; Kozlova, I; Johannesson, M; Nääs, E; Nordvall, S L; Dragomir, A; Roomans, G M

    2006-04-01

    The ionic composition of the airway surface liquid (ASL) in healthy individuals and in patients with cystic fibrosis (CF) has been debated. Ion transport properties of the upper airway epithelium are similar to those of the lower airways and it is easier to collect nasal ASL from the nose. ASL was collected with ion exchange beads, and the elemental composition of nasal fluid was determined by X-ray microanalysis in healthy subjects, CF patients, CF heterozygotes, patients with rhinitis, and with primary ciliary dyskinesia (PCD). In healthy subjects, the ionic concentrations were approximately isotonic. In CF patients, CF heterozygotes, rhinitis, and PCD patients, [Na] and [Cl] were significantly higher compared when compared with those in controls. [K] was significantly higher in CF and PCD patients compared with that in controls. Severely affected CF patients had higher ionic concentrations in their nasal ASL than in patients with mild or moderate symptoms. Female CF patients had higher levels of Na, Cl, and K than male patients. As higher salt concentrations in the ASL are also found in other patients with airway diseases involving chronic inflammation, it appears likely that inflammation-induced epithelial damage is important in determining the ionic composition of the ASL. PMID:16586482

  1. Postnatal Exposure History and Airways

    PubMed Central

    Murphy, Shannon R.; Schelegle, Edward S.; Edwards, Patricia C.; Miller, Lisa A.; Hyde, Dallas M.

    2012-01-01

    Postnatally, the lung continues to grow and differentiate while interacting with the environment. Exposure to ozone (O3) and allergens during postnatal lung development alters structural elements of conducting airways, including innervation and neurokinin abundance. These changes have been linked with development of asthma in a rhesus monkey model. We hypothesized that O3 exposure resets the ability of the airways to respond to oxidant stress and that this is mediated by changes in the neurokinin-1 receptor (NK-1R). Infant rhesus monkeys received episodic exposure to O3 biweekly with or without house dust mite antigen (HDMA) from 6 to 12 months of age. Age-matched monkeys were exposed to filtered air (FA). Microdissected airway explants from midlevel airways (intrapulmonary generations 5–8) for four to six animals in each of four groups (FA, O3, HDMA, and HDMA+O3) were tested for NK-1R gene responses to acute oxidant stress using exposure to hydrogen peroxide (1.2 mM), a lipid ozonide (10 μM), or sham treatment for 4 hours in vitro. Airway responses were measured using real-time quantitative RT-PCR of NK-1R and IL-8 gene expression. Basal NK-1R gene expression levels were not different between the exposure groups. Treatment with ozonide or hydrogen peroxide did not change NK-1R gene expression in animals exposed to FA, HDMA, or HDMA+O3. However, treatment in vitro with lipid ozonide significantly increased NK-1R gene expression in explants from O3–exposed animals. We conclude that a history of prior O3 exposure resets the steady state of the airways to increase the NK-1R response to subsequent acute oxidant stresses. PMID:22962062

  2. 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...

  3. 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.

  4. 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.

  5. Aspartame ingestion with and without carbohydrate in phenylketonuric and normal subjects: effect on plasma concentrations of amino acids, glucose, and insulin.

    PubMed

    Wolf-Novak, L C; Stegink, L D; Brummel, M C; Persoon, T J; Filer, L J; Bell, E F; Ziegler, E E; Krause, W L

    1990-04-01

    Seven subjects homozygous for phenylketonuria (PKU) and seven normal subjects were administered four beverage regimens after an overnight fast: unsweetened beverage, beverage providing carbohydrate (CHO), beverage providing aspartame (APM), and beverage providing APM plus CHO. The APM dose (200 mg) was the amount provided in 12 oz of diet beverage; the CHO was partially hydrolyzed starch (60 g). Plasma amino acid concentrations were determined after dosing and the molar plasma phenylalanine (Phe) to large neutral amino acid (LNAA) ratio calculated. APM administration without CHO did not increase plasma Phe concentrations over baseline values in either normal or PKU subjects (5.48 +/- 0.85 and 150 +/- 23.0 mumols/dL, respectively). Similarly, the Phe/LNAA did not increase significantly. Ingestion of beverage providing APM and CHO did not significantly increase plasma Phe concentrations over baseline values in either normal or PKU subjects. However, ingestion of beverage providing CHO (with or without APM) significantly decreased plasma levels of valine, isoleucine, and leucine 1.5 to 4 hours after dosing in both normal and PKU subjects, thereby increasing the Phe/LNAA ratio significantly. These data indicate that changes noted in Phe/LNAA values after ingestion of beverage providing APM plus CHO were due to CHO. The plasma insulin response to beverage providing CHO (with or without APM) was significantly higher in PKU subjects than in normals.

  6. [Airway equipment and its maintenance for a non difficult adult airway management (endotracheal intubation and its alternative: face mask, laryngeal mask airway, laryngeal tube)].

    PubMed

    Francon, D; Estèbe, J P; Ecoffey, C

    2003-08-01

    The airway equipment for a non difficult adult airway management are described: endotracheal tubes with a specific discussion on how to inflate the balloon, laryngoscopes and blades, stylets and intubation guides, oral airways, face masks, laryngeal mask airways and laryngeal tubes. Cleaning and disinfections with the maintenance are also discussed for each type of airway management.

  7. Inflammatory bowel disease and airway diseases

    PubMed Central

    Vutcovici, Maria; Brassard, Paul; Bitton, Alain

    2016-01-01

    Airway diseases are the most commonly described lung manifestations of inflammatory bowel disease (IBD). However, the similarities in disease pathogenesis and the sharing of important environmental risk factors and genetic susceptibility suggest that there is a complex interplay between IBD and airway diseases. Recent evidence of IBD occurrence among patients with airway diseases and the higher than estimated prevalence of subclinical airway injuries among IBD patients support the hypothesis of a two-way association. Future research efforts should be directed toward further exploration of this association, as airway diseases are highly prevalent conditions with a substantial public health impact. PMID:27678355

  8. Inflammatory bowel disease and airway diseases

    PubMed Central

    Vutcovici, Maria; Brassard, Paul; Bitton, Alain

    2016-01-01

    Airway diseases are the most commonly described lung manifestations of inflammatory bowel disease (IBD). However, the similarities in disease pathogenesis and the sharing of important environmental risk factors and genetic susceptibility suggest that there is a complex interplay between IBD and airway diseases. Recent evidence of IBD occurrence among patients with airway diseases and the higher than estimated prevalence of subclinical airway injuries among IBD patients support the hypothesis of a two-way association. Future research efforts should be directed toward further exploration of this association, as airway diseases are highly prevalent conditions with a substantial public health impact.

  9. Lung function and airway diseases.

    PubMed

    Weiss, Scott T

    2010-01-01

    Two studies report genome-wide association studies for lung function, using cross-sectional spirometric measurements in healthy individuals. They identify six genetic loci newly associated to natural variation in lung function, which may have implications for the related airway diseases of asthma and chronic obstructive pulmonary disease. PMID:20037613

  10. Management of the difficult airway.

    PubMed

    Schwartz, D E; Wiener-Kronish, J P

    1991-09-01

    For clinicians involved in airway management, a plan of action for dealing with the difficult airway or a failed intubation should be developed well in advance of encountering a patient in whom intubation is not routine. When difficulty is anticipated, the equipment necessary for performing a difficult intubation should be immediately available. It also is prudent to have a surgeon skilled in performing a tracheotomy and a criothyroidotomy stand by. The intubation should be attempted in the awake state, preferably using the fiberoptic bronchoscope. The more challenging situation is when the difficult airway is confronted unexpectedly. After the first failed attempt at laryngoscopy, head position should be checked and the patient ventilated with oxygen by mask. A smaller styletted tube and possibly a different laryngoscope blade should be selected for a second attempt at intubation. The fiberoptic bronchoscope and other equipment for difficult intubation should be obtained. A second attempt should then be made. If this is unsuccessful, the patient should be reoxygenated, and assistance including a skilled anesthesiologist and surgeon should be summoned. On a third attempt, traction to the tongue can be applied by an assistant, a tube changer could be used to enter the larynx, or one of the other special techniques previously described can be used. If this third attempt fails, it may be helpful to have a physician more experienced in airway management attempt intubation after oxygen has been administered to the patient. If all attempts are unsuccessful, then invasive techniques to secure the airway will have to be performed. PMID:1934950

  11. [Supraglottic airways in infants and children].

    PubMed

    Goldmann, Kai

    2013-04-01

    The development of the LMA-Classic™ revolutionized anaesthesia practice as its wide-spread use led to the establishment of a unique form of airway management, the "supraglottic airway management", besides the existing classical airway management with the face mask or endotracheal tube. Today, 25 years later, along with the original prototype of supraglottic airways quite a few numbers of different devices exist that can be used to secure the airway "above the glottis". After initially primarily marketing adult sizes many suppliers offer paediatric sizes nowadays. However, the scientific evidence in terms of superiority or at a least equality to the original LMA-Classic( of any of these airway devices must be considered insufficient except for the LMA-ProSeal™. Consequently, the routine use of these devices outside controlled clinical studies must be considered questionable. The following article aims at providing a critical appraisal of currently available supraglottic airway devices for neonates and infants. PMID:23633256

  12. Laryngeal mask airway: uses in anesthesiology.

    PubMed

    Pinosky, M

    1996-06-01

    The laryngeal mask airway (LMA), developed in 1983, is a new device to assist in the management of the pediatric and adult airway. In 1991, the Food and Drug Administration gave its approval for use of the LMA in the United States. The LMA is reusable and appears to provide cost-effective airway management in numerous situations. The LMA is simple to use, atraumatic to insert, and helpful in overcoming an obstructed airway. Its role in management of the difficult airway and the traumatic airway is still evolving. This review will introduce the LMA to the nonanesthesiologist and review for the anesthesiologist the origins of the LMA, its physical structure, the technical aspects of insertion, problems with aspiration, its role in the difficult airway, and experience with the pediatric population.

  13. 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. PMID:22082167

  14. Wavelet-Based Analytical Algorithm for Solving Steady-State Concentration in Immobilized Glucose Isomerase of Packed-Bed Reactor Model.

    PubMed

    Selvi, M Salai Mathi; Hariharan, G

    2016-08-01

    Wavelet method is a recently developed tool in applied mathematics. The mathematical model of the steady-state immobilized enzyme electrodes is discussed. This theoretical model is based on one-dimensional heat conduction equations containing a non-linear term related to Michaelis-Menten kinetics. An efficient Chebyshev wavelet-based technique is applied to solve the non-linear diffusion equation for the steady-state condition. A simple expression of the substrate concentration is obtained as a function of the Thiele modulus [Formula: see text] and [Formula: see text](kinetic parameter). The wavelet results are compared with the numerical and HPM solutions and found to be in good agreement.

  15. Wavelet-Based Analytical Algorithm for Solving Steady-State Concentration in Immobilized Glucose Isomerase of Packed-Bed Reactor Model.

    PubMed

    Selvi, M Salai Mathi; Hariharan, G

    2016-08-01

    Wavelet method is a recently developed tool in applied mathematics. The mathematical model of the steady-state immobilized enzyme electrodes is discussed. This theoretical model is based on one-dimensional heat conduction equations containing a non-linear term related to Michaelis-Menten kinetics. An efficient Chebyshev wavelet-based technique is applied to solve the non-linear diffusion equation for the steady-state condition. A simple expression of the substrate concentration is obtained as a function of the Thiele modulus [Formula: see text] and [Formula: see text](kinetic parameter). The wavelet results are compared with the numerical and HPM solutions and found to be in good agreement. PMID:27161606

  16. 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

  17. 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). PMID:24925919

  18. UPPER AIRWAY BLOCKS FOR AWAKE DIFFICULT AIRWAY MANAGEMENT.

    PubMed

    Pintaric, Tatjana Stopar

    2016-03-01

    Airway anesthesia is pivotal for successful awake intubation provided either topically or by blocks. Airway blocks are considered technically more difficult to perform and carry a higher risk of complications. However, in experienced hands, they can be useful as they provide excellent intubating conditions. For complete upper airway anesthesia, bilateral glossopharyngeal and superior laryngeal nerve blocks with translaryngeal injection are required. Superior laryngeal nerve block and translaryngeal injection can be performed easily, safely and with a high success rate in patients with normal anatomy. In those with difficult landmarks, ultrasound can be of assistance. For the superior laryngeal nerve block, other targets than the nerve itself must be established to make the technique consistently successful, easy to teach, learn and perform. The same applies to the translaryngeal injection, where the use of ultrasound is necessary for correct midline identification. Intraoral glossopharyngeal nerve block is also safe and easy to perform, but associated with long lasting discomfort. Bilateral extraoral peristyloid approach should be discouraged since inadvertent blocks of the closely adjacent vagus nerve cannot be prevented in this location. A safe and easy method of blocking the distal portions of the glossopharyngeal nerve for awake intubation is therefore required. PMID:27276778

  19. 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).

  20. Does nitrogen dioxide exposure increase airways responsiveness

    SciTech Connect

    Folinsbee, L.J.

    1992-01-01

    A number of reports have suggested that exposure to nitrogen dioxide (NO2) may cause increased airways responsiveness (AR). Twenty studies of asthmatics and five studies of healthy subjects exposed to NO[sub 2] were used to test the hypothesis using a simple method of meta-analysis. Individual data were obtained for the above studies and the direction of change in AR was determined for each subject. Only studies with available individual data were used. Subjects from these studies whose directional change in AR could not be determined were excluded. The fraction of positive responses (i.e. increased AR) was determined for all subjects within a group and tested for significance using a sign test. Data were also grouped according to NO[sub 2] concentration and by whether the exposure included exercise.

  1. Increased airways responsiveness in swine farmers.

    PubMed

    Zhou, C; Hurst, T S; Cockcroft, D W; Dosman, J A

    1991-04-01

    A respiratory questionnaire, pulmonary function tests, and an examination of airways responsiveness were conducted on 20 swine farmers and 20 control subjects. The swine farmers represented almost the complete work force from 13 Hutterite colonies and had worked in confinement buildings with more than 2,000 swine (3,270 +/- 1,221 swine) for at least four hours (6.6 +/- 1.8 hours) per day for more than two years (10.5 +/- 7.5 years). The control subjects were randomly selected from outdoor city workers from the city of Saskatoon and were matched for gender, age (+/- 2 years), and smoking status. Eleven swine farmers (55 percent) had chronic cough, compared with three (15 percent) of the control subjects (p less than 0.01). Eight (40 percent) of the swine farmers had symptoms of wheezing, compared with three (15 percent) of the control subjects (p less than 0.05). The FEV1 was significantly lower in swine farmers (97.2 +/- 11.5 percent predicted) than in control subjects (106.0 +/- 12.0 percent of predicted) (p less than 0.05). Airways responsiveness was measured by methacholine challenge with doubling concentrations ranging from 0.25 to 256 mg/ml. The provocation concentrations resulting in a reduction of 10 percent (PC10) and 20 percent (PC20) in FEV1 were lower in swine farmers than in control subjects (PC10, 77.2 +/- 78.8 mg/ml vs 180.8 +/- 96.5 mg/ml; p less than 0.01; and PC20, 154.5 +/- 99.9 mg/ml vs 229.6 +/- 66.8 mg/ml; p less than 0.05). Twelve swine farmers (60 percent) had PC20 of less than 256 mg/ml, compared with three (15 percent) of the control workers (p less than 0.01). Fewer swine farmers demonstrated atopy as measured by skin prick tests than did control workers (21 percent vs 56 percent; p less than 0.05). These findings suggested that occupational exposure in swine confinement buildings is associated with mild increases of nonspecific, nonatopic airways responsiveness in swine farmers. PMID:2009799

  2. Low Blood Glucose (Hypoglycemia)

    MedlinePlus

    ... Other Dental Problems Diabetic Eye Disease Low Blood Glucose (Hypoglycemia) What is hypoglycemia? Hypoglycemia, also called low ... actions can also help prevent hypoglycemia: Check blood glucose levels Knowing your blood glucose level can help ...

  3. 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. If glucose levels ...

  4. Endothelin receptor alterations in equine airway hyperreactivity

    PubMed Central

    2006-01-01

    Abstract The purpose of this study was to evaluate the role of endothelin-1 (ET-1) and its receptors in the airway hyperreactivity of horses with obstructive pulmonary disease associated with summer pasture (SPAOPD). The right diaphragmatic lobe of the lung of 8 clinically healthy (unaffected) and 8 SPAOPD-affected horses was collected immediately after euthanasia. Bronchial rings (4 mm wide) were prepared and mounted in organ baths and attached to force transducers interfaced with a polygraph. Four rings were used to study each ET-1 receptor; 1 ring served as the control, and the other 3 were incubated with 10−9, 10−7, or 10−5 M of either BQ-123, an ETA-receptor antagonist, or IRL-1038, an ETB-receptor antagonist. Cumulative concentrations (10−8.5 to 10−6 M) of ET-1 were applied to all rings. Using pooled pulmonary tissue from different regions of the lung, we performed a reverse-transcription polymerase chain reaction (RT-PCR) to determine ETB-receptor gene expression. Although ET-1 caused concentration-dependent bronchial ring contraction in both groups of horses, the rings of SPAOPD-affected horses had significantly greater contraction than the rings of unaffected horses. Whereas ETA-receptor blockade significantly increased the response to ET-1 in unaffected horses, ETB-receptor blockade significantly decreased the response in affected horses. The pA2 values showed a nonsignificant decrease in ETA-receptor affinity and a significant increase in ETB-receptor affinity in affected horses compared with unaffected horses. The ETB-receptor mRNA expression of the pooled pulmonary tissue showed a nonsignificant increase in affected horses compared with unaffected horses. The airway hyperreactivity to ET-1 observed in the bronchial rings from the affected horses appears to be due in part to activation of pulmonary ETB receptors, which appear to be inactive in unaffected horses. PMID:16548332

  5. Microwave dielectric resonator biosensor for aqueous glucose solution

    NASA Astrophysics Data System (ADS)

    Kim, Jongchul; Babajanyan, Arsen; Hovsepyan, Artur; Lee, Kiejin; Friedman, Barry

    2008-08-01

    We report a near-field microwave biosensor based on a dielectric resonator to detect glucose concentration. A microwave biosensor with a high Q dielectric resonator allows observation of the small variation of the glucose concentration by measuring the shift of the resonance frequency and the microwave reflection coefficient S11. We observed the concentration of glucose with a detectable resolution up to 5mg/ml at an operating frequency of about f =1.68GHz. The change in the glucose concentration is directly related to the change in the reflection coefficient due to the electromagnetic interaction between the dielectric resonator and the glucose solution.

  6. Dose-response relationship of ozone-induced airway hyperresponsiveness in unanesthetized guinea pigs

    SciTech Connect

    Nishikawa, M.; Suzuki, S.; Ikeda, H.; Fukuda, T.; Suzuki, J.; Okubo, T. )

    1990-06-01

    The effect of ozone dose (the product of ozone concentration and exposure time) on airway responsiveness was examined in unanesthetized, spontaneously breathing guinea pigs. Airway responsiveness was assessed by measuring specific airway resistance (sRaw) as a function of increasing concentration of inhaled methacholine (Mch) aerosol (the concentration of Mch required in order to double the baseline sRaw: PC200Mch). The airway responsiveness was measured before and at 5 min, 5 h, and 24 h after exposure. A 30-min exposure to 1 ppm ozone (dose 30 ppm.min) did not change PC200Mch at any time after exposure. Both a 90-min exposure to 1 ppm ozone and a 30-min exposure to 3 ppm ozone, which are identical in terms of ozone dose (90 ppm.min), decreased PC200Mch to a similar degree. A 120-min exposure to 3 ppm ozone (360 ppm.min) produced a much greater decrease of PC200Mch at 5 min and 5 h after exposure, compared with low-dose exposure. There was a significant correlation between ozone dose and the change in airway responsiveness. In all groups, the baseline sRaw was increased by approximately 50% at 5 min after exposure, but there was no correlation between the changes in PC200Mch and the baseline sRaw. This study suggests that ozone-induced airway hyperresponsiveness in guinea pigs is closely related to ozone dose.

  7. Naked eye detection of glucose in urine using glucose oxidase immobilized gold nanoparticles.

    PubMed

    Radhakumary, Changerath; Sreenivasan, Kunnatheeri

    2011-04-01

    Colloidal gold is extensively used for molecular sensing because of the flexibilities it offers in terms of modification of the gold nanoparticle surface with a variety of functional groups using thiol chemistry. We describe a simple assay that allows the visual detection of glucose in aqueous samples and demonstrates its applicability by estimating glucose in urine. To enable the glucose detection, we functionalized the thiol capped gold nanoparticles with glucose oxidase, the enzyme specific to β-D glucose, using carbodiimide chemistry. The visible color change of the GOD-functionalized gold nanoparticles from red to blue on interaction with glucose is the principle applied here for the sensing of urine glucose level. The solution turns blue when the glucose concentration exceeds 100 μg/mL. The approach depicted here seems to be important, particularly in third world countries where high tech diagnostics aids are inaccessible to the bulk of the population. PMID:21391552

  8. Glucose metabolism in diabetic blood vessels

    SciTech Connect

    Brown, B.J.; Crass, M.F. III

    1986-03-05

    Since glycolysis appears to be coupled to active ion transport in vascular smooth muscle, alterations in glucose metabolism may contribute to cellular dysfunction and angiopathy in diabetes. Uptake and utilization of glucose were studied in perfused blood vessels in which pulsatile flow and perfusion pressure were similar to those measured directly in vivo. Thoracic aortae isolated from 8-wk alloxan diabetic (D) and nondiabetic control rabbits were cannulated, tethered, and perfused with oxygenated buffer containing 7 or 25 mM glucose and tracer amounts of glucose-U/sup -14/ C. Norepinephrine (NE) (10/sup -6/ M) and/or insulin (I) (150 ..mu..U/ml) and albumin (0.2%) were added. NE-induced tension development increased glucose uptake 39% and /sup 14/CO/sub 2/ and lactate production 2.3-fold. With 7 mM glucose, marked decreases in glucose uptake (74%), /sup 14/CO/sub 2/ (68%), lactate (30%), total tissue glycogen (75%), and tissue phospholipids (70%) were observed in D. Addition of I or elevation of exogenous glucose to 25 mM normalized glucose uptake, but had differential effects on the pattern of substrate utilization. Thus, in D, there was a marked depression of vascular glucose metabolism that was partially reversed by addition of low concentrations of insulin or D levels of glucose.

  9. Airway management in cervical spine injury

    PubMed Central

    Austin, Naola; Krishnamoorthy, Vijay; Dagal, Arman

    2014-01-01

    To minimize risk of spinal cord injury, airway management providers must understand the anatomic and functional relationship between the airway, cervical column, and spinal cord. Patients with known or suspected cervical spine injury may require emergent intubation for airway protection and ventilatory support or elective intubation for surgery with or without rigid neck stabilization (i.e., halo). To provide safe and efficient care in these patients, practitioners must identify high-risk patients, be comfortable with available methods of airway adjuncts, and know how airway maneuvers, neck stabilization, and positioning affect the cervical spine. This review discusses the risks and benefits of various airway management strategies as well as specific concerns that affect patients with known or suspected cervical spine injury. PMID:24741498

  10. Airway obstruction in congenital central hypoventilation syndrome.

    PubMed

    Reverdin, Alexandra K; Mosquera, Ricardo; Colasurdo, Giuseppe N; Jon, Cindy K; Clements, Roya M

    2014-01-01

    Congenital central hypoventilation syndrome (CCHS) is the failure of the autonomic system to control adequate ventilation while asleep with preserved ventilatory response while awake. We report a case of a patient with CCHS who presented with intrathoracic and extrathoracic airway obstruction after tracheostomy tube decannulation and phrenic nerve pacer placement. Nocturnal polysomnography (NPSG) revealed hypoxia, hypercapnia and obstructive sleep apnoea, which required bilevel positive airway pressure titration. Airway endoscopy demonstrated tracheomalacia and paretic true vocal cords in the paramedian position during diaphragmatic pacing. Laryngeal electromyography demonstrated muscular electrical impulses that correlated with diaphragmatic pacer settings. Thus, we surmise that the patient's upper and lower airway obstruction was secondary to diaphragmatic pacer activity. Thorough airway evaluation, including NPSG and endoscopy, may help identify the side effects of diaphragmatic pacing, such as airway obstruction, in patients with CCHS.

  11. 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

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

    2015-09-01

    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 [(3)H]-ouabain binding. However, amiloride-sensitive uptake of (22)Na(+) 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.

  12. The glucose/glucose-6-phosphate cycle in the periportal and perivenous zone of rat liver.

    PubMed

    Jungermann, K; Heilbronn, R; Katz, N; Sasse, D

    1982-04-01

    Periportal and perivenous hepatocytes contain different activities (V) of antagonistic key enzymes such as glucokinase and glucose-6-phosphatase. In order to get an insight into the metabolism of the periportal and perivenous area the flux rates (v) of the glucose/glucose-6-phosphate cycle were calculated on the basis of the Michaelis-Menten equation using the measured zonal concentrations of glucose and glucose 6-phosphate, the zonal activities of glucokinase and glucose-6-phosphatase previously reported and the half-saturating substrate concentrations (Km) of the two enzymes found in the literature. The concentrations of glucose were obtained as a first approximation by measuring the concentrations in portal (= periportal) and hepatovenous (= perivenous) blood; those of glucose 6-phosphate were calculated from the levels determined in microdissected periportal and perivenous liver tissue. The calculations showed (a) that the overall cycling rates agreed remarkably well with those reported for intact animals and (b) that during a normal feeding rhythm the periportal zone should catalyze net glucose output and the perivenous zone should mediate net glucose uptake, as proposed by the model of 'metabolic zonation'.

  13. Noninvasive technique for measurement of glucose content in body

    NASA Astrophysics Data System (ADS)

    Agapiou, George; Theofanous, N. G.

    1998-07-01

    This work is focused on the measurement of glucose in various diluted solutions and aims to be implemented in testing the glucose content in the anterior chamber of the eye by means of an electro-optic modulation method. By using solutions containing only glucose concentrations, a calibration curve displaying the dependence of the glucose concentration on a DC field, applied to a modulator, was obtained.

  14. Innate immune response in CF airway epithelia: hyperinflammatory?

    PubMed

    Machen, Terry E

    2006-08-01

    The lack of functional cystic fibrosis (CF) transmembrane conductance regulator (CFTR) in the apical membranes of CF airway epithelial cells abolishes cAMP-stimulated anion transport, and bacteria, eventually including Pseudomonas aeruginosa, bind to and accumulate in the mucus. Flagellin released from P. aeruginosa triggers airway epithelial Toll-like receptor 5 and subsequent NF-kappaB signaling and production and release of proinflammatory cytokines that recruit neutrophils to the infected region. This response has been termed hyperinflammatory because so many neutrophils accumulate; a response that damages CF lung tissue. We first review the contradictory data both for and against the idea that epithelial cells exhibit larger-than-normal proinflammatory signaling in CF compared with non-CF cells and then review proposals that might explain how reduced CFTR function could activate such proinflammatory signaling. It is concluded that apparent exaggerated innate immune response of CF airway epithelial cells may have resulted not from direct effects of CFTR on cellular signaling or inflammatory mediator production but from indirect effects resulting from the absence of CFTRs apical membrane channel function. Thus, loss of Cl-, HCO3-, and glutathione secretion may lead to reduced volume and increased acidification and oxidation of the airway surface liquid. These changes concentrate proinflammatory mediators, reduce mucociliary clearance of bacteria and subsequently activate cellular signaling. Loss of apical CFTR will also hyperpolarize basolateral membrane potentials, potentially leading to increases in cytosolic [Ca2+], intracellular Ca2+, and NF-kappaB signaling. This hyperinflammatory effect of CF on intracellular Ca2+ and NF-kappaB signaling would be most prominently expressed during exposure to both P. aeruginosa and also endocrine, paracrine, or nervous agonists that activate Ca2+ signaling in the airway epithelia. PMID:16825601

  15. Rapid clearance of xanthines from airway and pulmonary tissues

    SciTech Connect

    Kroell, F.K.; Karlsson, J.A.; Nilsson, E.; Ryrfeldt, A.; Persson, C.G. )

    1990-05-01

    The airway and pulmonary fate of two antiasthma xanthines was examined in a guinea pig perfused lung preparation where the airway mechanics and airway microvascular perfusion are maintained at near normal values. 14C-theophylline or 14C-enprofylline was infused for 10, 30, and 300 s into the pulmonary artery of the guinea pig isolated lung. The radioactivity increased rapidly (within 10 s) in tracheobronchial as well as in lung tissue, confirming that the large airway microcirculation was well supplied also by the perfusion. The effluent concentrations of total 3H and 14C radioactivity at the onset, during, and after intrapulmonary infusion of 14C-labeled xanthines and 3H-sucrose were closely associated, suggesting that the xanthines, like sucrose, largely distributed in extracellular fluid and were not taken up by the tissues. No metabolites of enprofylline or theophylline could be detected in the lung tissue or lung effluent, suggesting that xanthines are not biotransformed by the guinea pig lung. After intratracheal instillation of 14C-theophylline, the peak radioactivity in the lung effluent appeared in the second 15-s fraction after instillation, and after 10 and 60 min, 68.1 +/- 4.7% and 86.9 +/- 8.4%, respectively, of the given dose had appeared in the lung effluent. The present data suggest a mainly extracellular distribution and a rapid clearance of xanthines from the lung and airway tissues. The rapid disappearance of topical theophylline may explain the lack of success of inhalation therapy with this drug.

  16. 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. PMID:27377929

  17. 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.

  18. AIRWAY VISUALIZATION: EYES SEE WHAT MIND KNOWS.

    PubMed

    Sorbello, Massimiliano; Frova, Giulio; Zdravković, Ivana

    2016-03-01

    Airway management is basic for anesthesia practice, and sometimes it can represent a really dramatic scenario for both the patient and the physicians. Laryngoscopy has been the gold standard of airway visualization for more than 60 years, showing its limitations and failure rates with time. New technology has made available an opportunity to move the physician's eye inside patient airways thanks to video laryngoscopy and video assisted airway management technique. Undoubtedly, we have entered a new era of high resolution airway visualization and different approach in airway instrumentation. Nevertheless, each new technology needs time to be tested and considered reliable, and pitfalls and limitations may come out with careful and long lasting analysis, so it is probably not the right time yet to promote video assisted approach as a new gold standard for airway visualization, despite the fact that it certainly offers some new prospects. In any case, whatever the visualization approach, no patient dies because of missed airway visualization or failed intubation, but due to failed ventilation, which remains without doubt the gold standard of any patient safety goal and airway management technique.

  19. 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

  20. Sequential Stenting for Extensive Malignant Airway Stenosis

    PubMed Central

    Takahama, Makoto; Nakajima, Ryu; Kimura, Michitaka; Tei, Keiko; Yamamoto, Ryoji

    2014-01-01

    Purpose: Malignant airway stenosis extending from the bronchial bifurcation to the lower lobar orifice was treated with airway stenting. We herein examine the effectiveness of airway stenting for extensive malignant airway stenosis. Methods: Twelve patients with extensive malignant airway stenosis underwent placement of a silicone Dumon Y stent (Novatech, La Ciotat, France) at the tracheal bifurcation and a metallic Spiral Z-stent (Medico’s Hirata, Osaka, Japan) at either distal side of the Y stent. We retrospectively analyzed the therapeutic efficacy of the sequential placement of these silicone and metallic stents in these 12 patients. Results: The primary disease was lung cancer in eight patients, breast cancer in two patients, tracheal cancer in one patient, and thyroid cancer in one patient. The median survival period after airway stent placement was 46 days. The Hugh–Jones classification and performance status improved in nine patients after airway stenting. One patient had prolonged hemoptysis and died of respiratory tract hemorrhage 15 days after the treatment. Conclusion: Because the initial disease was advanced and aggressive, the prognosis after sequential airway stent placement was significantly poor. However, because respiratory distress decreased after the treatment in most patients, this treatment may be acceptable for selected patients with extensive malignant airway stenosis. PMID:25273272

  1. Physical principle of airway design in human lungs

    NASA Astrophysics Data System (ADS)

    Park, Keunhwan; Son, Taeho; Kim, Wonjung; Kim, Ho-Young

    2014-11-01

    From an engineering perspective, lungs are natural microfluidic devices that extract oxygen from air. In the bronchial tree, airways branch by dichotomy with a systematic reduction of their diameters. It is generally accepted that in conducting airways, which air passes on the way to the acinar airways from the atmosphere, the reduction ratio of diameter is closely related to the minimization of viscous dissipation. Such a principle is formulated as the Hess-Murray law. However, in acinar airways, where oxygen transfer to alveolae occurs, the diameter reduction with progressive generations is more moderate than in conducting airways. Noting that the dominant transfer mechanism in acinar airways is diffusion rather than advection, unlike conducting airways, we construct a mathematical model for oxygen transfer through a series of acinar airways. Our model allows us to predict the optimal airway reduction ratio that maximizes the oxygen transfer in a finite airway volume, thereby rationalizing the observed airway reduction ratio in acinar airways.

  2. 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.

  3. Aluminum Gallium Nitride (GaN)/GaN High Electron Mobility Transistor-Based Sensors for Glucose Detection in Exhaled Breath Condensate

    PubMed Central

    Chu, Byung Hwan; Kang, Byoung Sam; Hung, Sheng Chun; Chen, Ke Hung; Ren, Fan; Sciullo, Andrew; Gila, Brent P.; Pearton, Stephen J.

    2010-01-01

    Background Immobilized aluminum gallium nitride (AlGaN)/GaN high electron mobility transistors (HEMTs) have shown great potential in the areas of pH, chloride ion, and glucose detection in exhaled breath condensate (EBC). HEMT sensors can be integrated into a wireless data transmission system that allows for remote monitoring. This technology offers the possibility of using AlGaN/GaN HEMTs for extended investigations of airway pathology of detecting glucose in EBC without the need for clinical visits. Methods HEMT structures, consisting of a 3-μm-thick undoped GaN buffer, 30-Å-thick Al0.3Ga0.7N spacer, and 220-Å-thick silicon-doped Al0.3Ga0.7N cap layer, were used for fabricating the HEMT sensors. The gate area of the pH, chloride ion, and glucose detection was immobilized with scandium oxide (Sc2O3), silver chloride (AgCl) thin film, and zinc oxide (ZnO) nanorods, respectively. Results The Sc2O3-gated sensor could detect the pH of solutions ranging from 3 to 10 with a resolution of ∼0.1 pH. A chloride ion detection limit of 10-8 M was achievedt with a HEMT sensor immobilized with the AgCl thin film. The drain–source current of the ZnO nanorod-gated AlGaN/GaN HEMT sensor immobilized with glucose oxidase showed a rapid response of less than 5 seconds when the sensor was exposed to the target glucose in a buffer with a pH value of 7.4. The sensor could detect a wide range of concentrations from 0.5 nM to 125 μM. Conclusion There is great promise for using HEMT-based sensors to enhance the detection sensitivity for glucose detection in EBC. Depending on the immobilized material, HEMT-based sensors can be used for sensingt different materials. These electronic detection approaches with rapid response and good repeatability show potential for the investigation of airway pathology. The devices can also be integrated into a wireless data transmission system for remote monitoring applications. This sensor technology could use the exhaled breath condensate to

  4. Blood Test: Glucose

    MedlinePlus

    ... Things to Know About Zika & Pregnancy Blood Test: Glucose KidsHealth > For Parents > Blood Test: Glucose Print A A A Text Size What's in ... de sangre: glucosa What It Is A blood glucose test measures the amount of glucose (the main ...

  5. 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

  6. Postprandial glucose and insulin profiles following a glucose-loaded meal in cats and dogs.

    PubMed

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

    2011-10-01

    Data from intravenous (i.v.) glucose tolerance tests suggest that glucose clearance from the blood is slower in cats than in dogs. Since different physiological pathways are activated following oral administration compared with i.v. administration, we investigated the profiles of plasma glucose and insulin in cats and dogs following ingestion of a test meal with or without glucose. Adult male and female cats and dogs were fed either a high-protein (HP) test meal (15 g/kg body weight; ten cats and eleven dogs) or a HP + glucose test meal (13 g/kg body-weight HP diet + 2 g/kg body-weight D-glucose; seven cats and thirteen dogs) following a 24 h fast. Marked differences in plasma glucose and insulin profiles were observed in cats and dogs following ingestion of the glucose-loaded meal. In cats, mean plasma glucose concentration reached a peak at 120 min (10.2, 95 % CI 9.7, 10.8 mmol/l) and returned to baseline by 240 min, but no statistically significant change in plasma insulin concentration was observed. In dogs, mean plasma glucose concentration reached a peak at 60 min (6.3, 95 % CI 5.9, 6.7 mmol/l) and returned to baseline by 90 min, while plasma insulin concentration was significantly higher than pre-meal values from 30 to 120 min following the glucose-loaded meal. These results indicate that cats are not as efficient as dogs at rapidly decreasing high blood glucose levels and are consistent with a known metabolic adaptation of cats, namely a lack of glucokinase, which is important for both insulin secretion and glucose uptake from the blood. PMID:22005400

  7. 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

  8. Cardiovascular effects of methacholine-induced airway obstruction in man.

    PubMed

    Sharman, J E; Johns, D P; Marrone, J; Walls, J; Wood-Baker, R; Walters, E H

    2014-06-01

    Cardiovascular disease is the most frequent cause of death in people with chronic respiratory disease. The cause of this association has been attributed to airway obstruction leading to cardiovascular dysfunction (increased central blood pressure (BP) and aortic stiffness). However, this has never been experimentally tested. Methacholine is routinely used to stimulate airway function changes that mimic airway pathology. This study aimed to determine the cardiovascular effects of methacholine-induced airway obstruction. Fifteen healthy young adults (aged 22.9±2.5 years; 4 male; mean±S.D.) underwent a bronchial challenge test (randomized, blinded, cross-over design) in which they received nebulized methacholine inhalation in serially increasing concentrations (from 0.39 to 25 mg/ml) or saline (0.9%; control) on two separate days. Bronchoconstriction was assessed by forced expiratory volume at one second (FEV1) and cardiovascular effects by augmentation index, brachial BP, central BP, heart rate and aortic stiffness. Methacholine significantly decreased FEV1 from baseline to peak inhaled concentration compared with saline (-0.48±0.34 vs. -0.07±0.16 L; p<0.001), but there was no between-group change in augmentation index (1.6±7.0 vs. 3.7±10.2% p=0.49), brachial systolic BP (-3.3±7.6 vs. -4.7±5.7 mmHg; p=0.59), central systolic BP (-1.1±5.2 vs. -0.3±5.5 mmHg; p=0.73), heart rate (0.4±7.1 vs. -0.8±6.6 bpm; p=0.45) or aortic stiffness (0.2±1.3 vs. 0.8±1.8 m/s; p=0.20; n=12). Thus, methacholine induced airway obstruction does not acutely change brachial BP or central haemodynamics. This finding refutes the notion that airway obstruction per se leads to cardiovascular dysfunction, at least in healthy individuals in the acute setting.

  9. 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. PMID:16475003

  10. Airway hyperresponsiveness in elite athletes.

    PubMed

    Langdeau, J B; Turcotte, H; Bowie, D M; Jobin, J; Desgagné, P; Boulet, L P

    2000-05-01

    It has been suggested that high-level training could contribute to the development of airway hyperresponsiveness (AHR), but the comparative effects of different sports on airway function remains to be determined. We evaluated 150 nonsmoking volunteers 18 to 55 yr of age; 100 athletes divided into four subgroups of 25 subjects each according to the predominant estimated hydrocaloric characteristic of ambient air inhaled during training: dry air (DA), cold air (CA), humid air (HA) and a mixture of dry and humid air (MA), and 50 sedentary subjects. Each subject had a respiratory questionnaire, a methacholine challenge, allergy skin-prick tests, and heart rate variability recording for evaluation of parasympathetic tone. The athletes had a 49% prevalence of AHR (PC(20) < 16 mg/ml), with a mean PC(20) of 16.9 mg/ml, compared with 28% (PC(20): 35.4) in sedentary subjects (p = 0.009). The prevalence (%) of AHR and mean PC(20) (mg/ml) varied as followed in the four subgroups of athletes: DA: 32% and 30.9; CA: 52% and 15.8; HA: 76% and 7.3; and MA: 32% and 21.5 (p = 0.002). The estimated parasympathetic tone was higher in athletes (p < 0.001), but this parameter showed only a weak correlation with PC(20) (r = -0.17, p = 0.04). This study has shown a significantly higher prevalence of AHR in athletes than in the control group because of the higher prevalence in the CA and HA groups. Parasympathetic activity may act as modulator of airway responsiveness, but the increased prevalence of AHR in our athlete population may be related to the type and possibly the content of inhaled air during training.

  11. Modeling Glucose Metabolism in the Kidney.

    PubMed

    Chen, Ying; Fry, Brendan C; Layton, Anita T

    2016-06-01

    The mammalian kidney consumes a large amount of energy to support the reabsorptive work it needs to excrete metabolic wastes and to maintain homeostasis. Part of that energy is supplied via the metabolism of glucose. To gain insights into the transport and metabolic processes in the kidney, we have developed a detailed model of the renal medulla of the rat kidney. The model represents water and solute flows, transmural fluxes, and biochemical reactions in the luminal fluid of the nephrons and vessels. In particular, the model simulates the metabolism of oxygen and glucose. Using that model, we have identified parameters concerning glucose transport and basal metabolism that yield predicted blood glucose concentrations that are consistent with experimental measurements. The model predicts substantial axial gradients in blood glucose levels along various medullary structures. Furthermore, the model predicts that in the inner medulla, owing to the relatively limited blood flow and low tissue oxygen tension, anaerobic metabolism of glucose dominates. PMID:27371260

  12. Continuous Glucose Monitoring Systems: A Review

    PubMed Central

    Vashist, Sandeep Kumar

    2013-01-01

    There have been continuous advances in the field of glucose monitoring during the last four decades, which have led to the development of highly evolved blood glucose meters, non-invasive glucose monitoring (NGM) devices and continuous glucose monitoring systems (CGMS). Glucose monitoring is an integral part of diabetes management, and the maintenance of physiological blood glucose concentration is the only way for a diabetic to avoid life-threatening diabetic complications. CGMS have led to tremendous improvements in diabetic management, as shown by the significant lowering of glycated hemoglobin (HbA1c) in adults with type I diabetes. Most of the CGMS have been minimally-invasive, although the more recent ones are based on NGM techniques. This manuscript reviews the advances in CGMS for diabetes management along with the future prospects and the challenges involved. PMID:26824930

  13. Monitoring breath during oral glucose tolerance tests.

    PubMed

    Ghimenti, S; Tabucchi, S; Lomonaco, T; Di Francesco, F; Fuoco, R; Onor, M; Lenzi, S; Trivella, M G

    2013-03-01

    The evolution of breath composition during oral glucose tolerance tests (OGTTs) was analysed by thermal desorption/gas chromatography/mass spectrometry in 16 subjects and correlated to blood glucose levels. The glucose tolerance tests classified five of the subjects as diabetics, eight as affected by impaired glucose tolerance and three as normoglycaemic. Acetone levels were generally higher in diabetics (average concentration values: diabetics, 300 ± 40 ppbv; impaired glucose tolerance, 350 ± 30 ppbv; normoglycaemic, 230 ± 20 ppbv) but the large inter-individual variability did not allow us to identify the three groups by this parameter alone. The exhalation of 3-hydroxy-butan-2-one and butane-2,3-dione, likely due to the metabolization of glucose by bacteria in the mouth, was also observed. Future work will involve the extension of the analyses to other volatile compounds by attempting to improve the level of discrimination between the various classes of subjects. PMID:23446273

  14. Microcalorimetric Measurements of Glucose Metabolism by Marine Bacterium Vibrio alginolyticus

    PubMed Central

    Gordon, Andrew S.; Millero, Frank J.; Gerchakov, Sol M.

    1982-01-01

    Microcalorimetric measurements of heat production from glucose by Vibrio alginolyticus were made to assess the viability of calorimetry as a technique for studying the metabolism of marine bacteria at organic nutrient concentrations found in marine waters. The results show that the metabolism of glucose by this bacterium can be measured by calorimetry at submicromolar concentrations. A linear correlation between glucose concentration and total heat production was observed over a concentration range of 8 mM to 0.35 μM. It is suggested that these data indicate a constant efficiency of metabolism for this bacterium over the wide range of glucose concentrations studied. PMID:16346131

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

    PubMed Central

    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.

    2008-01-01

    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. PMID:17470619

  16. 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 ...

  17. Airway and Extracellular Matrix Mechanics in COPD.

    PubMed

    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.

  18. Athletic Trainers' Knowledge Regarding Airway Adjuncts

    ERIC Educational Resources Information Center

    Edler, Jessica R.; Eberman, Lindsey E.; Kahanov, Leamor; Roman, Christopher; Mata, Heather Lynne

    2015-01-01

    Context: Research suggests that knowledge gaps regarding the appropriate use of airway adjuncts exist among various health care practitioners, and that knowledge is especially limited within athletic training. Objective: To determine the relationship between perceived knowledge (PK) and actual knowledge (AK) of airway adjunct use and the…

  19. 21 CFR 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 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....

  20. 21 CFR 868.5100 - Nasopharyngeal airway.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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....

  1. 21 CFR 868.5100 - Nasopharyngeal airway.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 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....

  2. 21 CFR 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 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....

  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 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 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....

  5. 21 CFR 868.5100 - Nasopharyngeal airway.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 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....

  6. 21 CFR 868.5100 - Nasopharyngeal airway.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 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....

  7. 21 CFR 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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....

  8. 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....

  9. 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

  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. 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

  12. Airway fires during surgery: Management and prevention

    PubMed Central

    Akhtar, Navaid; Ansar, Farrukh; Baig, Mirza Shahzad; Abbas, Akbar

    2016-01-01

    Airway fires pose a serious risk to surgical patients. Fires during surgery have been reported for many years with flammable anesthetic agents being the main culprits in the past. Association of airway fires with laser surgery is well-recognized, but there are reports of endotracheal tube fires ignited by electrocautery during pharyngeal surgery or tracheostomy or both. This uncommon complication has potentially grave consequences. While airway fires are relatively uncommon occurrences, they are very serious and can often be fatal. Success in preventing such events requires a thorough understanding of the components leading to a fire (fuel, oxidizer, and ignition source), as well as good communication between all members present to appropriately manage the fire and ensure patient safety. We present a case of fire in the airway during routine adenotonsillectomy. We will review the causes, preventive measures, and brief management for airway fires. PMID:27006554

  13. Airway fires during surgery: Management and prevention.

    PubMed

    Akhtar, Navaid; Ansar, Farrukh; Baig, Mirza Shahzad; Abbas, Akbar

    2016-01-01

    Airway fires pose a serious risk to surgical patients. Fires during surgery have been reported for many years with flammable anesthetic agents being the main culprits in the past. Association of airway fires with laser surgery is well-recognized, but there are reports of endotracheal tube fires ignited by electrocautery during pharyngeal surgery or tracheostomy or both. This uncommon complication has potentially grave consequences. While airway fires are relatively uncommon occurrences, they are very serious and can often be fatal. Success in preventing such events requires a thorough understanding of the components leading to a fire (fuel, oxidizer, and ignition source), as well as good communication between all members present to appropriately manage the fire and ensure patient safety. We present a case of fire in the airway during routine adenotonsillectomy. We will review the causes, preventive measures, and brief management for airway fires. PMID:27006554

  14. Awake Craniotomy: A New Airway Approach.

    PubMed

    Sivasankar, Chitra; Schlichter, Rolf A; Baranov, Dimitry; Kofke, W Andrew

    2016-02-01

    Awake craniotomies have been performed regularly at the University of Pennsylvania since 2004. Varying approaches to airway management are described for this procedure, including intubation with an endotracheal tube and use of a laryngeal mask airway, simple facemask, or nasal cannula. In this case series, we describe the successful use (i.e., no need for endotracheal intubation related to inadequate gas exchange) of bilateral nasopharyngeal airways in 90 patients undergoing awake craniotomies. The use of nasopharyngeal airways can ease the transition between the asleep and awake phases of the craniotomy without the need to stimulate the airway. Our purpose was to describe our experience and report adverse events related to this technique. PMID:26579845

  15. Anaesthetic management of acute airway obstruction

    PubMed Central

    Wong, Patrick; Wong, Jolin; Mok, May Un Sam

    2016-01-01

    The acutely obstructed airway is a medical emergency that can potentially result in serious morbidity and mortality. Apart from the latest advancements in anaesthetic techniques, equipment and drugs, publications relevant to our topic, including the United Kingdom’s 4th National Audit Project on major airway complications in 2011 and the updated American Society of Anesthesiologists’ difficult airway algorithm of 2013, have recently been published. The former contained many reports of adverse events associated with the management of acute airway obstruction. By analysing the data and concepts from these two publications, this review article provides an update on management techniques for the acutely obstructed airway. We discuss the principles and factors relevant to the decision-making process in formulating a logical management plan. PMID:26996162

  16. 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.

  17. Nucleotide release by airway epithelia.

    PubMed

    Lazarowski, Eduardo R; Sesma, Juliana I; Seminario, Lucia; Esther, Charles R; Kreda, Silvia M

    2011-01-01

    The purinergic events regulating the airways' innate defenses are initiated by the release of purines from the epithelium, which occurs constitutively and is enhanced by chemical or mechanical stimulation. While the external triggers have been reviewed exhaustively, this chapter focuses on current knowledge of the receptors and signaling cascades mediating nucleotide release. The list of secreted purines now includes ATP, ADP, AMP and nucleotide sugars, and involves at least three distinct mechanisms reflecting the complexity of airway epithelia. First, the constitutive mechanism involves ATP translocation to the ER/Golgi complex as energy source for protein folding, and fusion of Golgi-derived vesicles with the plasma membrane. Second, goblet cells package ATP with mucins into granules, which are discharged in response to P2Y(2)R activation and Ca(2+)-dependent signaling pathways. Finally, non-mucous cells support a regulated mechanism of ATP release involving protease activated receptor (PAR)-elicited G(12/13) activation, leading to the RhoGEF-mediated exchange of GDP for GTP on RhoA, and cytoskeleton rearrangement. Together, these pathways provide fine tuning of epithelial responses regulated by purinergic signaling events. PMID:21560042

  18. Puberty and Upper Airway Dynamics During Sleep

    PubMed Central

    Bandla, Preetam; Huang, Jingtao; Karamessinis, Laurie; Kelly, Andrea; Pepe, Michelle; Samuel, John; Brooks, Lee; Mason, Thornton. A.; Gallagher, Paul R.; Marcus, Carole L.

    2008-01-01

    Study Objectives: The upper airway compensatory response to subatmospheric pressure loading declines with age. The epidemiology of obstructive sleep apnea suggests that sex hormones play a role in modulating upper airway function. Sex hormones increase gradually during puberty, from minimally detectable to adult levels. We hypothesized that the upper airway response to subatmospheric pressure loading decreased with increasing pubertal Tanner stage in males but remained stable during puberty in females. Design: Upper airway dynamic function during sleep was measured over the course of puberty. Participants: Normal subjects of Tanner stages 1 to 5. Measurements: During sleep, maximal inspiratory airflow was measured while varying the level of nasal pressure. The slope of the upstream pressure-flow relationship (SPF) was measured. Results: The SPF correlated with age and Tanner stage. However, the relationship with Tanner stage became nonsignificant when the correlation due to the mutual association with age was removed. Females had a lower SPF than males. Conclusions: In both sexes, the upper airway compensatory response to subatmospheric pressure loading decreased with age rather than degree of pubertal development. Thus, changes in sex hormones are unlikely to be a primary modulator of upper airway function during the transition from childhood to adulthood. Although further studies of upper airway structural changes during puberty are needed, we speculate that the changes in upper airway function with age are due to the depressant effect of age on ventilatory drive, leading to a decrease in upper airway neuromotor tone. Citation: Bandla P; Huang J; Karamessinis L; Kelly A; Pepe M; Samuel J; Brooks L; Mason TA; Gallagher PR; Marcus CL. Puberty and Upper Airway Dynamics During Sleep. SLEEP 2008;31(4):534-541. PMID:18457241

  19. [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. PMID:25823935

  20. 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.

  1. Acute regulation of tight junction ion selectivity in human airway epithelia

    PubMed Central

    Flynn, Andrea N.; Itani, Omar A.; Moninger, Thomas O.; Welsh, Michael J.

    2009-01-01

    Electrolyte transport through and between airway epithelial cells controls the quantity and composition of the overlying liquid. Many studies have shown acute regulation of transcellular ion transport in airway epithelia. However, whether ion transport through tight junctions can also be acutely regulated is poorly understood both in airway and other epithelia. To investigate the paracellular pathway, we used primary cultures of differentiated human airway epithelia and assessed expression of claudins, the primary determinants of paracellular permeability, and measured transepithelial electrical properties, ion fluxes, and La3+ movement. Like many other tissues, airway epithelia expressed multiple claudins. Moreover, different cell types in the epithelium expressed the same pattern of claudins. To evaluate tight junction regulation, we examined the response to histamine, an acute regulator of airway function. Histamine stimulated a rapid and transient increase in the paracellular Na+ conductance, with a smaller increase in Cl− conductance. The increase was mediated by histamine H1 receptors and depended on an increase in intracellular Ca2+ concentration. These results suggest that ion flow through the paracellular pathway can be acutely regulated. Such regulation could facilitate coupling of the passive flow of counter ions to active transcellular transport, thereby controlling net transepithelial salt and water transport. PMID:19208806

  2. 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

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

    PubMed

    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.

  4. Breakfast, blood glucose, and cognition.

    PubMed

    Benton, D; Parker, P Y

    1998-04-01

    This article compares the findings of three studies that explored the role of increased blood glucose in improving memory function for subjects who ate breakfast. An initial improvement in memory function for these subjects was found to correlate with blood glucose concentrations. In subsequent studies, morning fasting was found to adversely affect the ability to recall a word list and a story read aloud, as well as recall items while counting backwards. Failure to eat breakfast did not affect performance on an intelligence test. It was concluded that breakfast consumption preferentially influences tasks requiring aspects of memory. In the case of both word list recall and memory while counting backwards, the decline in performance associated with not eating breakfast was reversed by the consumption of a glucose-supplemented drink. Although a morning fast also affected the ability to recall a story read aloud, the glucose drink did not reverse this decline. It appears that breakfast consumption influences cognition via several mechanisms, including an increase in blood glucose. PMID:9537627

  5. Kinetics of glucose isomerization to fructose by immobilized glucose isomerase: anomeric reactivity of D-glucose in kinetic model.

    PubMed

    Lee, H S; Hong, J

    2001-11-30

    The substrate specificity of immobilized D-glucose isomerase (EC 5.3. 1.5) is investigated with an immobilized enzyme-packed reactor. A series of isomerization experiments with alpha-, beta-, and equilibrated D-glucose solutions indicates that beta anomer as well as alpha anomer is a substrate of the glucose isomerase at pH 7.5 and 60 degrees C. For substrate concentration of 0.028 mol l(-1) (1% w/v), the initial conversion rate of alpha-D-glucose was 43% higher than that with equilibrated glucose at the same concentration and 113% higher than beta-D-glucose conversion rate. This anomeric reactivity of glucose isomerase is mathematically described with a set of kinetic equations based on the reaction steps complying with Briggs-Haldane mechanism and the experimentally determined kinetic constants. The proposed reaction mechanism includes the mutarotation and the isomerization reactions of alpha- and beta-D-glucose with different rate constants.

  6. 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.

  7. Hydroxycitric acid delays intestinal glucose absorption in rats.

    PubMed

    Wielinga, Peter Y; Wachters-Hagedoorn, Renate E; Bouter, Brenda; van Dijk, Theo H; Stellaard, Frans; Nieuwenhuizen, Arie G; Verkade, Henkjan J; Scheurink, Anton J W

    2005-06-01

    In this study, we investigated in rats if hydroxycitric acid (HCA) reduces the postprandial glucose response by affecting gastric emptying or intestinal glucose absorption. We compared the effect of regulator HCA (310 mg/kg) and vehicle (control) on the glucose response after an intragastric or intraduodenal glucose load to investigate the role of altered gastric emptying. Steele's one-compartment model was used to investigate the effect of HCA on systemic glucose appearance after an intraduodenal glucose load, using [U-(13)C]-labeled glucose and d-[6,6-(2)H(2)]-labeled glucose. Because an effect on postabsorptive glucose clearance could not be excluded, the effect of HCA on the appearance of enterally administered glucose in small intestinal tissue, liver, and portal and systemic circulation was determined by [U-(14)C]glucose infusion. Data show that HCA treatment delays the intestinal absorption of enterally administered glucose at the level of the small intestinal mucosa in rats. HCA strongly attenuated postprandial blood glucose levels after both intragastric (P < 0.01) and intraduodenal (P < 0.001) glucose administration, excluding a major effect of HCA on gastric emptying. HCA delayed the systemic appearance of exogenous glucose but did not affect the total fraction of glucose absorbed over the study period of 150 min. HCA treatment decreased concentrations of [U-(14)C]glucose in small intestinal tissue at 15 min after [U-(14)C]glucose administration (P < 0.05), in accordance with the concept that HCA delays the enteral absorption of glucose. These data support a possible role for HCA as food supplement in lowering postprandial glucose profiles. PMID:15604199

  8. 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. PMID:26390345

  9. 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.

  10. Development of a Robust Optical Glucose Sensor

    NASA Astrophysics Data System (ADS)

    Cote, Gerard Laurence

    1990-01-01

    The long term objective of this research was the development of a noninvasive, optically-based, polarimetric sensor to monitor in vivo glucose concentrations. The goal of diabetes therapy is to approximate the 24-hour blood glucose profile of a normal individual. There have been major advances in the development of reliable, versatile, and accurate pumps for the delivery of insulin to diabetic patients and in the development of control algorithms for closed-loop insulin delivery, however, there remain major obstacles to the development of clinically useful, continuous glucose sensors. The development of an accurate noninvasive glucose sensor would have significant application in the diagnosis and management of diabetes mellitis both in conjunction with, and independent of, the glucose pump controller applications. The linear polarization vector of light routes when it interacts with an optically active material such as glucose. The amount of rotation of polarization is directly proportional to the glucose concentration and to the path length. The ability to quantitate blood glucose levels for the limited available path length in our primary sensing site, namely, the anterior chamber of the eye, therefore depends on the signal-to-noise ratio of the polarization detector. Our primary research focused on the development and testing of a prototype optical polarimetry system using D + glucose solution in a test cell, as well as using an enucleated human eye to assess the sensitivity of the system to measure physiologic glucose levels for the approximate one centimeter path length present in the anterior chamber of the eye. Our research has led to the development of a true phase technique in which helium neon laser light was coupled through a rotating linear polarizer along with two stationary linear polarizers and two detectors to produce reference and signal outputs whose amplitudes varied sinusoidally and whose phase was proportional to the rotation of light caused by

  11. 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.

  12. Zinc oxide nanoparticles induce eosinophilic airway inflammation in mice.

    PubMed

    Huang, Kuo-Liang; Lee, Yi-Hsin; Chen, Hau-Inh; Liao, Huang-Shen; Chiang, Bor-Luen; Cheng, Tsun-Jen

    2015-10-30

    Zinc oxide nanoparticles (ZnO NPs) have been widely used in industry. The metal composition of PM2.5 might contribute to the higher prevalence of asthma. To investigate the effects of ZnO NPs on allergic airway inflammation, mice were first exposed to different concentrations of ZnO NPs (0.1 mg/kg, 0.5 mg/kg) or to a combination of ZnO NPs and chicken egg ovalbumin (OVA) by oropharyngeal aspiration on day 0 and day 7 and then were sacrificed 5 days later. The subsequent time course of airway inflammation in the mice after ZnO NPs exposure was evaluated on days 1, 7, and 14. To further determine the role of zinc ions, ZnCl2 was also administered. The inflammatory cell count, cytokine levels in the bronchoalveolar lavage fluid (BALF), and lung histopathology were examined. We found significant neutrophilia after exposure to high-dose ZnO NPs on day 1 and significant eosinophilia in the BALF at 7 days. However, the expression levels of the T helper 2 (Th2) cytokines IL-4, IL-5, and IL-13 increased significantly after 24h of exposure to only ZnO NPs and then decreased gradually. These results suggested that ZnO NPs could cause eosinophilic airway inflammation in the absence of allergens.

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

    PubMed

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

    2015-08-01

    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.

  14. Gas transport in branched airways during high-frequency ventilation.

    PubMed

    Scherer, P W; Haselton, F R; Seybert, J R

    1984-01-01

    A theoretical model of high-frequency ventilation (HFV) is presented based on the physical convective exchange process that occurs due to the irreversibility of gas velocity profiles in oscillatory flow through the bronchial airways. Mass transport during the convective exchange process can be characterized by a convective exchange length, LE, which depends only on the irreversibility of bronchial velocity profiles and can be measured by the experimental technique of photographic flow visualization in bronchial tree models. Using the exchange length and the molecular diffusivity, a simple model of overall bronchial mass transfer is developed. The model allows a prediction of the mean gas concentration profiles along the airways, the site of maximum mass transfer resistance, and overall flow rate of the gas of interest in or out of the lung as functions of the parameters of HFV. The results predicted by the model agree with the limited experimental data available for animals and humans. For normal unassisted ventilation, total bronchial cross-sectional area around the 15th Weibel bronchial generation is predicted to be the single most important parameter in controlling the total gas transport rate along the airways. For the breathing of room air, values of the respiratory quotient around 0.78 are predicted, which are insensitive to VT and f. The model represents a fruitful combination of fluid mechanical theory and experiment with physiologic data to yield new and deeper insight into the operation of the human respiratory system during HFV and normal breathing.

  15. 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…

  16. Small particles disrupt postnatal airway development

    PubMed Central

    Lee, DongYoub; Wallis, Chris; Schelegle, Edward S.; Van Winkle, Laura S.; Plopper, Charles G.; Fanucchi, Michelle V.; Kumfer, Ben; Kennedy, Ian M.; Chan, Jackie K. W.

    2010-01-01

    Increasing numbers of epidemiologic studies associate air pollution exposure in children with decreased lung function development. The objective of this study was to examine the effects of exposure to combustion-generated fine [230 and 212 nm number mean aerodynamic particle diameter (NMAD)] to ultrafine (73 nm NMAD) particles differing in elemental (EC) and organic (OC) carbon content on postnatal airway development in rats. Neonatal Sprague-Dawley rats were exposed from postnatal day 7 through 25, and lung function and airway architecture were evaluated 81 days of age. In a separate group of rats, cell proliferation was examined after a single particle exposure at 7 days of age. Early life exposure to 73 nm high OC/EC particles altered distal airway architecture and resulted in subtle changes in lung mechanics. Early life exposure to 212 nm high OC/EC particles did not alter lung architecture but did alter lung mechanics in a manner suggestive of central airway changes. In contrast, early life exposure to 230 nm low OC/EC particles did not alter lung architecture or mechanics. A single 6-h exposure to 73 nm high OC/EC particle decreased airway cell proliferation, whereas 212 nm high OC/EC particles increased it and 230 nm low OC/EC particles did not. The early life exposure to ultrafine, high OC/EC particles results in persistent alterations in distal airway architecture that is characterized by an initial decrease in airway cell proliferation. PMID:20634362

  17. 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.

  18. Glucose-6-phosphate dehydrogenase

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003671.htm Glucose-6-phosphate dehydrogenase test To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) is a type of ...

  19. Your Glucose Meter

    MedlinePlus

    ... by Audience For Women Women's Health Topics Your Glucose Meter Share Tweet Linkedin Pin it More sharing ... Español Basic Facts 7 Tips for Testing Your Blood Sugar and Caring for Your Meter Glucose meters test ...

  20. Insulin Control of Glucose Metabolism in Man

    PubMed Central

    Insel, Paul A.; Liljenquist, John E.; Tobin, Jordan D.; Sherwin, Robert S.; Watkins, Paul; Andres, Reubin; Berman, Mones

    1975-01-01

    Analyses of the control of glucose metabolism by insulin have been hampered by changes in bloog glucose concentration induced by insulin administration with resultant activation of hypoglycemic counterregulatory mechanisms. To eliminate such mechanisms, we have employed the glucose clamp technique which allows maintenance of fasting blood glucose concentration during and after the administration of insulin. Analyses of six studies performed in young healthy men in the postabsorptive state utilizing the concurrent administration of [14C]glucose and 1 mU/kg per min (40 mU/m2 per min) porcine insulin led to the development of kinetic models for insulin and for glucose. These models account quantitatively for the control of insulin on glucose utilization and on endogenous glucose production during nonsteady states. The glucose model, a parallel three-compartment model, has a central compartment (mass = 68±7 mg/kg; space of distribution = blood water volume) in rapid equilibrium with a smaller compartment (50±17 mg/kg) and in slow equilibrium with a larger compartment (96±21 mg/kg). The total plasma equivalent space for the glucose system averaged 15.8 liters or 20.3% body weight. Two modes of glucose loss are introduced in the model. One is a zero-order loss (insulin and glucose independent) from blood to the central nervous system; its magnitude was estimated from published data. The other is an insulin-dependent loss, occurring from the rapidly equilibrating compartment and, in the basal period, is smaller than the insulin-independent loss. Endogenous glucose production averaged 1.74 mg/kg per min in the basal state and enters the central compartment directly. During the glucose clamp experiments plasma insulin levels reached a plateau of 95±8 μU/ml. Over the entire range of insulin levels studied, glucose losses were best correlated with levels of insulin in a slowly equilibrating insulin compartment of a three-compartment insulin model. A proportional control

  1. 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)

  2. Trehalose-Mediated Autophagy Impairs the Anti-Viral Function of Human Primary Airway Epithelial Cells

    PubMed Central

    Wu, Qun; Jiang, Di; Huang, Chunjian; van Dyk, Linda F.; Li, Liwu; Chu, Hong Wei

    2015-01-01

    Human rhinovirus (HRV) is the most common cause of acute exacerbations of chronic lung diseases including asthma. Impaired anti-viral IFN-λ1 production and increased HRV replication in human asthmatic airway epithelial cells may be one of the underlying mechanisms leading to asthma exacerbations. Increased autophagy has been shown in asthmatic airway epithelium, but the role of autophagy in anti-HRV response remains uncertain. Trehalose, a natural glucose disaccharide, has been recognized as an effective autophagy inducer in mammalian cells. In the current study, we used trehalose to induce autophagy in normal human primary airway epithelial cells in order to determine if autophagy directly regulates the anti-viral response against HRV. We found that trehalose-induced autophagy significantly impaired IFN-λ1 expression and increased HRV-16 load. Inhibition of autophagy via knockdown of autophagy-related gene 5 (ATG5) effectively rescued the impaired IFN-λ1 expression by trehalose and subsequently reduced HRV-16 load. Mechanistically, ATG5 protein interacted with retinoic acid-inducible gene I (RIG-I) and IFN-β promoter stimulator 1 (IPS-1), two critical molecules involved in the expression of anti-viral interferons. Our results suggest that induction of autophagy in human primary airway epithelial cells inhibits the anti-viral IFN-λ1 expression and facilitates HRV infection. Intervention of excessive autophagy in chronic lung diseases may provide a novel approach to attenuate viral infections and associated disease exacerbations. PMID:25879848

  3. A glucose oxidase-coupled DNAzyme sensor for glucose detection in tears and saliva.

    PubMed

    Liu, Chengcheng; Sheng, Yongjie; Sun, Yanhong; Feng, Junkui; Wang, Shijin; Zhang, Jin; Xu, Jiacui; Jiang, Dazhi

    2015-08-15

    Biosensors have been widely investigated and utilized in a variety of fields ranging from environmental monitoring to clinical diagnostics. Glucose biosensors have triggered great interest and have been widely exploited since glucose determination is essential for diabetes diagnosis. In here, we designed a novel dual-enzyme biosensor composed of glucose oxidase (GOx) and pistol-like DNAzyme (PLDz) to detect glucose levels in tears and saliva. First, GOx, as a molecular recognition element, catalyzes the oxidation of glucose forming H2O2; then PLDz recognizes the produced H2O2 as a secondary signal and performs a self-cleavage reaction promoted by Mn(2+), Co(2+) and Cu(2+). Thus, detection of glucose could be realized by monitoring the cleavage rate of PLDz. The slope of the cleavage rate of PLDz versus glucose concentration curve was fitted with a Double Boltzmann equation, with a range of glucose from 100 nM to 10mM and a detection limit of 5 μM. We further applied the GOx-PLDz 1.0 biosensor for glucose detection in tears and saliva, glucose levels in which are 720±81 μM and 405±56 μM respectively. Therefore, the GOx-PLDz 1.0 biosensor is able to determine glucose levels in tears and saliva as a noninvasive glucose biosensor, which is important for diabetic patients with frequent/continuous glucose monitoring requirements. In addition, induction of DNAzyme provides a new approach in the development of glucose biosensors.

  4. Mechanisms Linking Advanced Airway Management and Cardiac Arrest Outcomes

    PubMed Central

    Benoit, Justin L.; Prince, David K.; Wang, Henry E.

    2015-01-01

    Advanced airway management – such as endotracheal intubation (ETI) or supraglottic airway (SGA) insertion – is one of the most prominent interventions in out-of-hospital cardiac arrest (OHCA) resuscitation. While randomized controlled trials are currently in progress to identify the best advanced airway technique in OHCA, the mechanisms by which airway management may influence OHCA outcomes remain unknown. We provide a conceptual model describing potential mechanisms linking advanced airway management with OHCA outcomes. PMID:26073275

  5. Nasal airway responses to nasal continuous positive airway pressure breathing: An in-vivo pilot study.

    PubMed

    White, David E; Bartley, Jim; Shakeel, Muhammad; Nates, Roy J; Hankin, Robin K S

    2016-06-14

    The nasal cycle, through variation in nasal airflow partitioning, allows the upper airway to accommodate the contrasting demands of air conditioning and removal of entrapped air contaminants. The purpose of this study was to investigate the influence of nasal continuous positive airway pressure (nCPAP) breathing has on both nasal airflow partitioning and nasal geometry. Using a custom-made nasal mask, twenty healthy participants had the airflow in each naris measured during normal nasal breathing followed by nCPAP breathing. Eight participants also underwent magnetic resonance imaging (MRI) of the nasal region during spontaneous nasal breathing, and then nCPAP breathing over a range of air pressures. During nCPAP breathing, a simultaneous reduction in airflow through the patent airway together with a corresponding increase in airway flow within the congested nasal airway were observed in sixteen of the twenty participants. Nasal airflow resistance is inversely proportional to airway cross-sectional area. MRI data analysis during nCPAP breathing confirmed airway cross-sectional area reduced along the patent airway while the congested airway experienced an increase in this parameter. During awake breathing, nCPAP disturbs the normal inter-nasal airflow partitioning. This could partially explain the adverse nasal drying symptoms frequently reported by many users of this therapy. PMID:27173595

  6. Chemotaxis and Binding of Pseudomonas aeruginosa to Scratch-Wounded Human Cystic Fibrosis Airway Epithelial Cells.

    PubMed

    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

  7. Influence of chronological aging on the survival and nucleotide content of Saccharomyces cerevisiae cells grown in different conditions: occurrence of a high concentration of UDP-N-acetylglucosamine in stationary cells grown in 2% glucose.

    PubMed

    Osório, Hugo; Silles, Eduardo; Maia, Rita; Peleteiro, Bárbara; Moradas-Ferreira, Pedro; Günther Sillero, María A; Sillero, Antonio

    2005-02-01

    Saccharomyces cerevisiae cells (strain W303) grown in a minimal medium (containing 2% or 0.1% glucose) until exponential or stationary phase, were subjected to chronological aging in water, and yeast viability and nucleotide content were analyzed along several days of nutrient starvation. Cells collected in exponential phase (whether grown in the presence of 0.1% or 2% glucose) were viable up to five days and thereafter the viability decreased linearly with a half-survival rate of around eight days. ATP and other nucleoside triphosphates decreased similarly in both cases. Cells collected in stationary phase, and transferred to water, behaved differently whether grown in 0.1% or in 2% glucose, with a half-survival life of around nine and 28 days respectively. A double mutant in glycogen synthase (gsy1delta gsy2delta) and its isogenic wild-type strain, grown to stationary phase in 2% glucose, presented a similar half-survival life of around eight days. The W303 cells grown to stationary phase in the presence of 2% glucose showed a 7-fold increase of UDP-N-acetylglucosamine (UDP-GlcNAc) as compared with the level present in the cells grown in any of the other three metabolic situations. The nature of UDP-GlcNAc was established by MALDI-TOF ionization analysis. It is also worth noting that the rate of decay of NAD+ was lower than that of ATP in any of the situations here considered.

  8. 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 ...

  9. 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.

  10. Extravascular fibrin, plasminogen activator, plasminogen activator inhibitors, and airway hyperresponsiveness

    PubMed Central

    Wagers, Scott S.; Norton, Ryan J.; Rinaldi, Lisa M.; Bates, Jason H.T.; Sobel, Burton E.; Irvin, Charles G.

    2004-01-01

    Mechanisms underlying airway hyperresponsiveness are not yet fully elucidated. One of the manifestations of airway inflammation is leakage of diverse plasma proteins into the airway lumen. They include fibrinogen and thrombin. Thrombin cleaves fibrinogen to form fibrin, a major component of thrombi. Fibrin inactivates surfactant. Surfactant on the airway surface maintains airway patency by lowering surface tension. In this study, immunohistochemically detected fibrin was seen along the luminal surface of distal airways in a patient who died of status asthmaticus and in mice with induced allergic airway inflammation. In addition, we observed altered airway fibrinolytic system protein balance consistent with promotion of fibrin deposition in mice with allergic airway inflammation. The airways of mice were exposed to aerosolized fibrinogen, thrombin, or to fibrinogen followed by thrombin. Only fibrinogen followed by thrombin resulted in airway hyperresponsiveness compared with controls. An aerosolized fibrinolytic agent, tissue-type plasminogen activator, significantly diminished airway hyperresponsiveness in mice with allergic airway inflammation. These results are consistent with the hypothesis that leakage of fibrinogen and thrombin and their accumulation on the airway surface can contribute to the pathogenesis of airway hyperresponsiveness. PMID:15232617

  11. Sodium coupled glucose co-transporters contribute to hypothalamic glucose-sensing

    PubMed Central

    O'Malley, Dervla; Reimann, Frank; Simpson, Anna K; Gribble, Fiona M

    2007-01-01

    Specialised neurons within the hypothalamus have the ability to sense and respond to changes in ambient glucose concentrations. We investigated the mechanisms underlying glucose-triggered activity in glucose-excited (GE) neurons, using primary cultures of rat hypothalamic neurons monitored by fluorescence calcium imaging. 35% (738/2139) of neurons were excited by increasing glucose from 3 to 15mM, but only 9% (6/64) of these GE neurons were activated by tolbutamide, suggesting the involvement of a KATP channel-independent mechanism. α-Methylglucopyranoside (αMDG, 12mM), a non-metabolisable substrate of sodium glucose co-transporters (SGLTs), mimicked the effect of high glucose in 67% of GE neurons, and both glucose and αMDG-triggered excitation were blocked by Na+ removal or by the SGLT inhibitor, phloridzin (100nM). In the presence of 0.5mM glucose and tolbutamide, responses could also be triggered by 3.5mM αMDG, supporting a role for an SGLT-associated mechanism at low as well as high substrate concentrations. By RT-PCR, we detected SGLT1, SGLT3a, SGLT3b in both cultured neurons and adult rat hypothalamus. Our findings suggest a novel role for SGLTs in glucose-sensing by hypothalamic GE neurons. PMID:17130483

  12. 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

  13. 21 CFR 868.5810 - Airway connector.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... airway connector is a device intended to connect a breathing gas source to a tracheal tube, tracheostomy tube, or mask. (b) Classification. Class I (general controls). The device is exempt from the...

  14. 21 CFR 868.5810 - Airway connector.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... airway connector is a device intended to connect a breathing gas source to a tracheal tube, tracheostomy tube, or mask. (b) Classification. Class I (general controls). The device is exempt from the...

  15. 21 CFR 868.5810 - Airway connector.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... airway connector is a device intended to connect a breathing gas source to a tracheal tube, tracheostomy tube, or mask. (b) Classification. Class I (general controls). The device is exempt from the...

  16. Virtual Airway Skills Trainer (VAST) Simulator

    PubMed Central

    DEMIREL, Doga; YU, Alexander; HALIC, Tansel; SANKARANARAYANAN, Ganesh; RYASON, Adam; SPINDLER, David; BUTLER, Kathryn L.; CAO, Caroline; PETRUSA, Emil; MOLINA, Marcos; JONES, Dan; DE, Suvranu; DEMOYA, Marc; JONES, Stephanie

    2016-01-01

    This paper presents a simulation of Virtual Airway Skill Trainer (VAST) tasks. The simulated tasks are a part of two main airway management techniques; Endotracheal Intubation (ETI) and Cricothyroidotomy (CCT). ETI is a simple nonsurgical airway management technique, while CCT is the extreme surgical alternative to secure the airway of a patient. We developed identification of Mallampati class, finding the optimal angle for positioning pharyngeal/mouth axes tasks for ETI and identification of anatomical landmarks and incision tasks for CCT. Both ETI and CCT simulators were used to get physicians’ feedback at Society for Education in Anesthesiology and Association for Surgical Education spring meetings. In this preliminary validation study, total 38 participants for ETI and 48 for CCT performed each simulation task and completed pre and post questionnaires. In this work, we present the details of the simulation for the tasks and also the analysis of the collected data from the validation study. PMID:27046559

  17. 21 CFR 868.5810 - Airway connector.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... airway connector is a device intended to connect a breathing gas source to a tracheal tube, tracheostomy tube, or mask. (b) Classification. Class I (general controls). The device is exempt from the...

  18. 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 ...

  19. Airway clearance therapy: finding the evidence.

    PubMed

    Volsko, Teresa A

    2013-10-01

    Disease processes can impair ciliary function, alter secretion production and mucus rheology, and interfere with the cough reflex. Airway clearance therapy has been a cornerstone of therapy aimed at minimizing the devastating effects of airway obstruction, infection, and inflammation due to mucus stasis on the conducting airways and lung parenchyma. Although challenges to performing clinical studies evaluating the effectiveness of airway clearance therapeutic modalities exist, resources are available in the literature. In addition to device evaluations and original clinical research, the expert opinion, systematic reviews, and evidence-based practice guidelines can be found. These tools can be used to develop protocols and pathways to guide our practice. Monitoring and reporting patient, process, and financial outcomes are essential steps germane to the implementation of evidence-based care.

  20. [Glucose Metabolism: Stress Hyperglycemia and Glucose Control].

    PubMed

    Tanaka, Katsuya; Tsutsumi, Yasuo M

    2016-05-01

    It is important for the anesthesiologists to understand pathophysiology of perioperative stress hyperglycemia, because it offers strategies for treatment of stress hyperglycemia. The effect of glucose tolerance is different in the choice of the anesthetic agent used in daily clinical setting. Specifically, the volatile anesthetics inhibit insulin secretion after glucose load and affects glucose tolerance. During minor surgery by the remifentanil anesthesia, the stress reaction is hard to be induced, suggesting that we should consider low-dose glucose load. Finally it is necessary to perform the glycemic control of the patients who fell into stress hyperglycemia depending on the individual patient. However, there are a lot of questions to be answered in the future. The prognosis of the perioperative patients is more likely to be greatly improved if we can control stress hyperglycemia.

  1. [Glucose Metabolism: Stress Hyperglycemia and Glucose Control].

    PubMed

    Tanaka, Katsuya; Tsutsumi, Yasuo M

    2016-05-01

    It is important for the anesthesiologists to understand pathophysiology of perioperative stress hyperglycemia, because it offers strategies for treatment of stress hyperglycemia. The effect of glucose tolerance is different in the choice of the anesthetic agent used in daily clinical setting. Specifically, the volatile anesthetics inhibit insulin secretion after glucose load and affects glucose tolerance. During minor surgery by the remifentanil anesthesia, the stress reaction is hard to be induced, suggesting that we should consider low-dose glucose load. Finally it is necessary to perform the glycemic control of the patients who fell into stress hyperglycemia depending on the individual patient. However, there are a lot of questions to be answered in the future. The prognosis of the perioperative patients is more likely to be greatly improved if we can control stress hyperglycemia. PMID:27319094

  2. Airway obstruction secondary to rhinoscleroma during pregnancy.

    PubMed

    Armstrong, W B; Peskind, S P; Bressler, K L; Crockett, D M

    1995-11-01

    Dyspnea is a fairly common complaint during pregnancy. However, if one excludes allergic nasal congestion of pregnancy, upper airway obstruction is a distinctly uncommon cause of dyspnea in the pregnant patient. Three cases of laryngeal rhinoscleroma in pregnant women requiring tracheostomy for airway management are reported. All three delivered healthy infants vaginally. Postpartum, two of the three were successfully decannulated, while the third became pregnant again before decannulation was accomplished. Treatment options and a review of the literature are presented.

  3. Short communication: Interrelationship between butyrate and glucose supply on butyrate and glucose oxidation by ruminal epithelial preparations.

    PubMed

    Wiese, B I; Górka, P; Mutsvangwa, T; Okine, E; Penner, G B

    2013-09-01

    The aim of this study was to determine whether dietary Na-butyrate supplementation affects butyrate and glucose oxidation by ruminal epithelial preparations and whether this effect can be acutely modulated by substrate (glucose and butyrate) supply. Eighteen Suffolk wether lambs (6 lambs/treatment) were blocked by body weight and, within block, randomly assigned to the control treatment (CON) or to diets containing differing Na-butyrate inclusion rates (1.58 or 3.16%) equating to 1.25 (B1.25), and 2.50% (B2.50) butyrate on a dry matter basis, respectively. All lambs received their diet for a period of 14 d. After dietary adaptation, lambs were killed and the ruminal epithelium was harvested from the ventral sac, minced finely, and used for in vitro incubations. Incubation medium contained either a constant concentration of glucose (4 mM) with increasing butyrate concentrations (0, 5, 15, 25, or 40 mM) or a constant butyrate concentration (15 mM) with increasing glucose concentrations (0, 1, 2, 4, or 8 mM) to allow for the evaluation of whether acute changes in the concentration of metabolic substrates affect the oxidation of glucose and butyrate. We observed no interactions between the in vivo and in vitro treatments. Increasing dietary butyrate supplementation linearly decreased glucose oxidation by ruminal epithelial preparations, but had no effect on butyrate oxidation. Increasing butyrate concentration in vitro decreased (cubic effect) glucose oxidation when butyrate concentration ranged between 5 and 15 mM; however, glucose oxidation was increased with a butyrate concentration of 40 mM. Butyrate oxidation decreased (cubic effect) as glucose concentration increased from 1 to 4 mM; however, butyrate oxidation increased when glucose was included at 8mM. The results of this study demonstrate that dietary butyrate supplementation can decrease glucose oxidation by the ruminal epithelium, but the relative supply of glucose and butyrate has a pronounced effect on

  4. Small Airway Dysfunction and Abnormal Exercise Responses

    PubMed Central

    Petsonk, Edward L.; Stansbury, Robert C.; Beeckman-Wagner, Lu-Ann; Long, Joshua L.; Wang, Mei Lin

    2016-01-01

    Rationale Coal mine dust exposure can cause symptoms and loss of lung function from multiple mechanisms, but the roles of each disease process are not fully understood. Objectives We investigated the implications of small airway dysfunction for exercise physiology among a group of workers exposed to coal mine dust. Methods Twenty coal miners performed spirometry, first breathing air and then helium-oxygen, single-breath diffusing capacity, and computerized chest tomography, and then completed cardiopulmonary exercise testing. Measurements and Main Results Six participants meeting criteria for small airway dysfunction were compared with 14 coal miners who did not. At submaximal workload, miners with small airway dysfunction used a higher proportion of their maximum voluntary ventilation and had higher ventilatory equivalents for both O2 and CO2. Regression modeling indicated that inefficient ventilation was significantly related to small airway dysfunction but not to FEV1 or diffusing capacity. At the end of exercise, miners with small airway dysfunction had 27% lower O2 consumption. Conclusions Small airway abnormalities may be associated with important inefficiency of exercise ventilation. In dust-exposed individuals with only mild abnormalities on resting lung function tests or chest radiographs, cardiopulmonary exercise testing may be important in defining causes of exercise intolerance. PMID:27073987

  5. Migration of Airway Smooth Muscle Cells

    PubMed Central

    Gerthoffer, William T.

    2008-01-01

    Migration of smooth muscle cells is a process fundamental to development of hollow organs, including blood vessels and the airways. Migration is also thought to be part of the response to tissue injury. It has also been suggested to contribute to airways remodeling triggered by chronic inflammation. In both nonmuscle and smooth muscle cells numerous external signaling molecules and internal signal transduction pathways contribute to cell migration. The review includes evidence for the functional significance of airway smooth muscle migration, a summary of promigratory and antimigratory agents, and summaries of important signaling pathways mediating migration. Important signaling pathways and effector proteins described include small G proteins, phosphatidylinositol 3-kinases (PI3-K), Rho activated protein kinase (ROCK), p21-activated protein kinases (PAK), Src family tyrosine kinases, and mitogen-activated protein kinases (MAPK). These signaling modules control multiple critical effector proteins including actin nucleating, capping and severing proteins, myosin motors, and proteins that remodel microtubules. Actin filament remodeling, focal contact remodeling and propulsive force of molecular motors are all coordinated to move cells along gradients of chemical cues, matrix adhesiveness, or matrix stiffness. Airway smooth muscle cell migration can be modulated in vitro by drugs commonly used in pulmonary medicine including β-adrenergic agonists and corticosteroids. Future studies of airway smooth muscle cell migration may uncover novel targets for drugs aimed at modifying airway remodeling. PMID:18094091

  6. Trichobezoar Causing Airway Compromise during Esophagogastroduodenoscopy

    PubMed Central

    Kao, Erica Y.; Scalzitti, Nicholas J.; Dion, Gregory R.; Bowe, Sarah N.

    2015-01-01

    Objectives. (1) Report the case of a 5-year-old female with trichotillomania and trichophagia that suffered airway compromise during esophagogastroduodenoscopy for removal of a trichobezoar. (2) Provide management recommendations for an unusual foreign body causing extubation and partial airway obstruction. Methods. Case report of a rare situation of airway compromise caused by a trichobezoar. Results. A 5-year-old patient underwent endoscopic retrieval of a gastric trichobezoar (hairball) by the gastroenterology service under general endotracheal anesthesia in a sedation unit. During removal, the hairball, due to its large size, dislodged the endotracheal tube, effectively extubating the patient. The bezoar became lodged at the cricopharyngeus muscle. Attempts to remove the bezoar or reintubation were unsuccessful. The child was able to be mask ventilated while the otolaryngology service was called. Direct laryngoscopy revealed a hairball partially obstructing the view of the glottis from its position in the postcricoid area. The hairball, still entrapped in the snare from the esophagoscope, was grasped with Magill forceps and slowly extracted. The patient was then reintubated and the airway and esophagus were reevaluated. Conclusions. Trichobezoar is an uncommon cause of airway foreign body. Careful attention to airway management during these and similar foreign body extractions can prevent inadvertent extubations. PMID:26457086

  7. 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. PMID:27466851

  8. 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

  9. Autocorrelation optical coherence tomography for glucose quantification in blood

    NASA Astrophysics Data System (ADS)

    Ullah, H.; Gilanie, G.; Hussain, F.; Ahmad, E.

    2015-12-01

    We report a new method for glucose monitoring in blood tissue based on the autocorrelation function (ACF) analysis in Fourier domain optical coherence tomography (FD-OCT). We have determined the changes in OCT monitoring signals’ depth to characterize the modulations in ACFs for quantitative measurements of glucose concentrations in blood. We found that an increase in the concentration of glucose in blood results in decreased OCT monitoring signal due to the increase in the refractive index of the media.

  10. Urinary glucose and vitamin C.

    PubMed

    Brandt, R; Guyer, K E; Banks, W L

    1977-11-01

    The recent popularization of self-prescribed large doses of vitamin C has increased the possibility for erroneous conclusions to be drawn from standard clinical methods used in urinary glucose monitoring, due to interference with these methods by the greatly elevated excretion of vitamin C. The coupled-enzyme-chromogen strip tests showed erroneously negative glucose levels in urines of both a diabetic individual and a subject with a genetic low renal threshold for glucose when they were supplementing their normal diets with 1-2 g vitamin C per day. With this regimen, their urinary vitamin C levels reached 200 mg/dl (11.4 mmol/l). For normal urine with vitamin C added, false-positive tests for glucose were found using Benedict's reagent when vitamin C was present at 250 mg/dl (14.3 mmol/l) or higher concentrations. In diabetic individuals consuming large quantities of vitamin C, this interference with standard coupled-enzyme-chromogen strip tests or Benedict's test could present a significant problem in diagnosis and clinical management of the disease. A simple anion exchange method of treating the urine was used to correct the false results. PMID:920657

  11. Ambient ozone causes upper airways inflammation in children.

    PubMed

    Frischer, T M; Kuehr, J; Pullwitt, A; Meinert, R; Forster, J; Studnicka, M; Koren, H

    1993-10-01

    Ozone constitutes a major air pollutant in Western Europe. During the summer national air quality standards are frequently exceeded, which justifies concern about the health effects of ozone at ambient concentrations. We studied upper airways inflammation after ozone exposure in 44 children by repeated nasal lavages from May to October 1991. During this time period five to eight lavages were performed for each child. On 14 days following high ozone exposure (daily maximum > or = 180 micrograms/m3) 148 nasal lavages were performed, and on 10 days following low ozone exposure (daily maximum < or = 140 micrograms/m3) 106 nasal lavages were performed. A significant increase of intra-individual mean polymorphonuclear leukocytes (PMN) counts from low ozone days (median, 20.27 x 10(3)) to high ozone days (median, 27.38 x 10(3); p < 0.01) was observed. Concomitant with a decrease of ozone concentrations in the fall mean PMN counts showed a downward trend. Linear regression analysis of log-PMN counts yielded a significant effect for ozone (p = 0.017). In a subsample humoral markers of inflammation were measured for each child's highest and lowest exposure. A significant increase was observed for eosinophilic cationic protein (median, 77.39 micrograms/L on low ozone days versus 138.6 micrograms/L on high ozone days; p < 0.05). Thus we conclude that ozone at ambient concentrations initiates a reversible inflammatory response of the upper airways in normal children.

  12. Surface tension of airway aspirates withdrawn during neonatal resuscitation reflects lung maturity.

    PubMed

    Stichtenoth, Guido; Walter, Gabi; Lange, Romy; Raith, Marco; Bernhard, Wolfgang; Herting, Egbert

    2014-08-01

    The indications for treatment of neonates with exogenous pulmonary surfactant are still discussed controversially. Some premature neonates are sufficiently treated by CPAP, others need conventional ventilation and/or surfactant. The available lung maturity tests have limitations. The captive bubble surfactometer (CBS) provides measurement of surface activity from rather small amounts of surfactant. This study aimed to determine surface activity from small volume aspirates of the upper airways of neonates by means of the CBS and to correlate the results with clinical data. Small upper airway aspirates from 159 neonates (gestational age 25-42 weeks) were withdrawn and concentrated 16.7-fold by ultracentrifugation and resuspension in saline. Surface activities after 5 min of adsorption were determined in the CBS and correlated to the perinatal data (e.g., gestational age, birth weight, gender), airway interventions (like CPAP, conventional ventilation) and surfactant treatment. Additionally, 27 samples were analyzed for surfactant specific phosphatidylcholine concentrations by using electrospray ionization tandem mass-spectroscopy. Surface activities show a significant correlation to gestational age, birth weight, and the need for airway interventions. Comparing the need for airway interventions versus surface activity, a receiver operating characteristic calculated a sensitivity of 0.77 and a specificity of 0.72 at a "cut off" of 44 mN/m. Surface activity correlates significantly with the phosphatidylcholine concentrations and the latter one correlates with the gestational age. Determination of surface activity from upper airway aspirates is feasible. Further clinical studies are needed to prove the predictive value of the method.

  13. O3-induced mucosa-linked airway muscle hyperresponsiveness in the guinea pig

    SciTech Connect

    Murlas, C.G.; Murphy, T.P.; Chodimella, V. )

    1990-07-01

    We investigated the effects of ozone exposure (3.0 ppm, 2 h) on the responsiveness of guinea pig airway muscle in vitro from animals developing bronchial hyperreactivity. Muscarinic reactivity in vivo was determined by measuring specific airway resistance (sRaw) in response to increasing concentrations of aerosolized acetylcholine (ACh) administered before and 30 min after exposure. Immediately after reactivity testing, multiple tracheal rings from ozone- and air-exposed animals were prepared and the contractile responses to increasing concentrations of substance P, ACh, or KCl were assessed in the presence of 10 microM indomethacin with or without 1 microM phosphoramidon, an inhibitor of neutral endopeptidase. Isometric force generation in vitro was measured on stimulation by cumulative concentrations of the agonists, and force generation (in g/cm2) was calculated after determination of muscle cross-sectional area. The smooth muscle of mucosa-intact airways from guinea pigs with ozone-induced bronchial hyper-reactivity proved to be hyperresponsive in vitro to substance P and ACh but not to KCl. Pretreatment with phosphoramidon abolished the increase in substance P responsiveness but had no effect on muscarinic hyperresponsiveness after ozone exposure. Furthermore, substance P responsiveness was not augmented in ozone-exposed airways in which the mucosa had been removed before testing in vitro. Likewise, muscarinic hyperresponsiveness was not present in ozone-exposed airways without mucosa. Our data indicate that airway smooth muscle responsiveness is increased in guinea pigs with ozone-induced bronchial hyperreactivity and suggest that this hyperresponsiveness may be linked to non-cyclooxygenase mucosa-derived factors.

  14. Etiology and pathogenesis of airway disease in children and adults from rural communities.

    PubMed Central

    Schwartz, D A

    1999-01-01

    Asthma is the most common chronic disease of childhood and affects nearly 5 million children. The prevalence and severity of childhood asthma have continued to increase over the past decade despite major advances in the recognition and treatment of this condition. A comparison of urban and rural children suggests that the etiology of airway disease is multifactorial and that unique exposures and genetic factors contribute to the development of asthma in both settings. The most important environmental exposure that distinguishes the rural environment and is known to cause asthma is the organic dusts. However, animal-derived proteins, common allergens, and low concentrations of irritants also contribute to the development of airway disease in children and adults living in rural communities. A fundamental unanswered question regarding asthma is why only a minority of children who wheeze at an early age develop persistent airway disease that continues throughout their life. Although genetic factors are important in the development of asthma, recurrent airway inflammation, presumably mediated by environmental exposures, may result in persistent airway hyperresponsiveness and the development of chronic airway disease. Increasing evidence indicates that control of the acute inflammatory response substantially improves airflow and reduces chronic airway remodeling. Reducing exposure to agricultural dusts and treatment with anti-inflammatory medication is indicated in most cases of childhood asthma. In addition, children with asthma from rural (in comparison to urban) America face multiple barriers that adversely affect their health e.g., more poverty, geographic barriers to health care, less health insurance, and poorer access to health care providers. These unique problems must be considered in developing interventions that effectively reduce the morbidity and mortality of asthma in children from rural communities. Images Figure 1 Figure 2 Figure 3 PMID:10346988

  15. 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.

  16. 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.

  17. 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...

  18. Endogenous nitrogen oxides and bronchodilator S-nitrosothiols in human airways.

    PubMed Central

    Gaston, B; Reilly, J; Drazen, J M; Fackler, J; Ramdev, P; Arnelle, D; Mullins, M E; Sugarbaker, D J; Chee, C; Singel, D J

    1993-01-01

    Recent discoveries suggesting essential bioactivities of nitric oxide (NO.) in the lung are difficult to reconcile with the established pulmonary cytotoxicity of this common air pollutant. These conflicting observations suggest that metabolic intermediaries may exist in the lung to modulate the bioactivity and toxicity of NO.. We report that S-nitrosothiols (RS-NO), predominantly the adduct with glutathione, are present at nano- to micromolar concentrations in the airways of normal subjects and that their levels vary in different human pathophysiologic states. These endogenous RS-NO are long-lived, potent relaxants of human airways under physiological O2 concentrations. Moreover, RS-NO form in high concentrations upon administration of NO. gas. Nitrite (10-20 microM) is found in airway lining fluid in concentrations linearly proportional to leukocyte counts, suggestive of local NO. metabolism. NO. itself was not detected either free in solution or in complexes with transition metals. These observations may provide insight into the means by which NO. is packaged in biological systems to preserve its bioactivity and limit its potential O2-dependent toxicity and suggest an important role for NO. in regulation of airway luminal homeostasis. PMID:8248198

  19. Full Airway Drainage by Fiber Bronchoscopy Through Artificial Airway in the Treatment of Occult Traumatic Atelectasis.

    PubMed

    Zhao, Xue Hong; Zhang, Yun; Liang, Zhong Yan; Zhang, Shao Yang; Yu, Wen Qiao; Huang, Fang-Fang

    2015-12-01

    The objective of this study is to investigate the effects of full airway drainage by fiber bronchoscopy through artificial airway in the treatment of traumatic atelectasis with occult manifestations. From May 2006 to May 2011, 40 cases of occult traumatic atelectasis were enrolled into our prospective study. Group A (n = 18) received drainage by nasal bronchoscope; group B underwent airway drainage by fiber bronchoscopy through artificial airway (n = 22). The effects of treatment were evaluated by the incidence of adult respiratory distress syndrome (ARDS), lung abscess, and the average length of hospital stay. Compared with nasal fiber-optic treatment, airway drainage by fiber bronchoscopy through artificial airway reduced the incidence of ARDS (p = 0.013) and lung abscess (p = 0.062) and shortened the mean length of stay (p = 0.018). Making the decision to create an artificial airway timely and carry out lung lavage by fiber bronchoscopy through artificial airway played a significant role in the treatment of occult traumatic atelectasis. PMID:27011511

  20. Full Airway Drainage by Fiber Bronchoscopy Through Artificial Airway in the Treatment of Occult Traumatic Atelectasis.

    PubMed

    Zhao, Xue Hong; Zhang, Yun; Liang, Zhong Yan; Zhang, Shao Yang; Yu, Wen Qiao; Huang, Fang-Fang

    2015-12-01

    The objective of this study is to investigate the effects of full airway drainage by fiber bronchoscopy through artificial airway in the treatment of traumatic atelectasis with occult manifestations. From May 2006 to May 2011, 40 cases of occult traumatic atelectasis were enrolled into our prospective study. Group A (n = 18) received drainage by nasal bronchoscope; group B underwent airway drainage by fiber bronchoscopy through artificial airway (n = 22). The effects of treatment were evaluated by the incidence of adult respiratory distress syndrome (ARDS), lung abscess, and the average length of hospital stay. Compared with nasal fiber-optic treatment, airway drainage by fiber bronchoscopy through artificial airway reduced the incidence of ARDS (p = 0.013) and lung abscess (p = 0.062) and shortened the mean length of stay (p = 0.018). Making the decision to create an artificial airway timely and carry out lung lavage by fiber bronchoscopy through artificial airway played a significant role in the treatment of occult traumatic atelectasis.

  1. 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

  2. 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.

  3. Effects of ozone on airway epithelial permeability and ion transport

    SciTech Connect

    Bromberg, P.A.; Ranga, V.; Stutts, M.J. )

    1991-12-01

    Ozone is a highly reactive form of oxygen produced in the atmosphere by photochemical reactions involving substrates emitted from automobile engines. Outdoor air concentrations as high as 0.4 parts per million (ppm) occur. The respiratory tract extracts about 90% of inhaled ozone. From the chemical reactivity of ozone, it is expected to attack organic molecules located on or near the respiratory surfaces. The airways are covered with a cohesive layer of epithelial cells that forms the boundary between the external environment and the respiratory tissues. One important role of this epithelial layer is its barrier function. Airborne particles that deposit (and dissolve) in the airway surface liquid are not readily absorbed, and soluble tissue components are excluded from the surface liquid. The epithelium also controls the volume and composition of the surface liquid. One important process in this regard is the absorption and secretion of ions and water. We have studied the effects of inhalation of ozone on the barrier function (permeability to dissolved molecules) and the ion transport activity of epithelium using both in vivo and in vitro techniques. All our experiments were performed with male Hartley strain guinea pigs. Conscious, unrestrained animals were exposed to a concentration of ozone of 1 ppm for three hours in controlled environmental chambers in the Health Effects Research Laboratory, U.S. Environmental Protection Agency (EPA), Research Triangle Park, NC. Such exposures caused a marked increase in the rate of appearance in blood of various water-soluble compounds instilled onto the surface of the trachea, indicating increased permeability of the airway epithelium.

  4. Delivered dose estimate to standardize airway hyperresponsiveness assessment in mice.

    PubMed

    Robichaud, Annette; Fereydoonzad, Liah; Schuessler, Thomas F

    2015-04-15

    Airway hyperresponsiveness often constitutes a primary outcome in respiratory studies in mice. The procedure commonly employs aerosolized challenges, and results are typically reported in terms of bronchoconstrictor concentrations loaded into the nebulizer. Yet, because protocols frequently differ across studies, especially in terms of aerosol generation and delivery, direct study comparisons are difficult. We hypothesized that protocol variations could lead to differences in aerosol delivery efficiency and, consequently, in the dose delivered to the subject, as well as in the response. Thirteen nebulization patterns containing common protocol variations (nebulization time, duty cycle, particle size spectrum, air humidity, and/or ventilation profile) and using increasing concentrations of methacholine and broadband forced oscillations (flexiVent, SCIREQ, Montreal, Qc, Canada) were created, characterized, and studied in anesthetized naïve A/J mice. A delivered dose estimate calculated from nebulizer-, ventilator-, and subject-specific characteristics was introduced and used to account for protocol variations. Results showed that nebulization protocol variations significantly affected the fraction of aerosol reaching the subject site and the delivered dose, as well as methacholine reactivity and sensitivity in mice. From the protocol variants studied, addition of a slow deep ventilation profile during nebulization was identified as a key factor for optimization of the technique. The study also highlighted sensitivity differences within the lung, as well as the possibility that airway responses could be selectively enhanced by adequate control of nebulizer and ventilator settings. Reporting results in terms of delivered doses represents an important standardizing element for assessment of airway hyperresponsiveness in mice. PMID:25637610

  5. An overview of muscle glucose uptake during exercise. Sites of regulation.

    PubMed

    Wasserman, D H; Halseth, A E

    1998-01-01

    The uptake of blood glucose by skeletal muscle is a complex process. In order to be metabolized, glucose must travel the path from blood to interstitium to intracellular space and then be phosphorylated to glucose 6-phosphate (G6P). Movement of glucose from blood to interstitium is determined by skeletal muscle blood flow, capillary recruitment and the endothelial permeability to glucose. The influx of glucose from the interstitium to intracellular space is determined by the number of glucose transporters in the sarcolemma and the glucose gradient across the sarcolemma. The capacity to phosphorylate glucose is determined by the amount of skeletal muscle hexokinase II, hexokinase II compartmentalization within the cell, and the concentration of the hexokinase II inhibitor G6P. Any change in glucose uptake occurs due to an alteration in one or more of these steps. Based on the low calculated intracellular glucose levels and the higher affinity of glucose for phosphorylation relative to transport, glucose transport is generally considered rate-determining for basal muscle glucose uptake. Exercise increases both the movement of glucose from blood to sarcolemma and the permeability of the sarcolemma to glucose. Whether the ability to phosphorylate glucose is increased in the working muscle remains to be clearly shown. It is possible that the accelerated glucose delivery and transport rates during exercise bias regulation so that muscle glucose phosphorylation exerts more control on muscle glucose uptake. Conditions that alter glucose uptake during exercise, such as increased NEFA concentrations, decreased oxygen availability and adrenergic stimulation, must work by altering one or more of the three steps involved in glucose uptake. This review describes the regulation of glucose uptake during exercise at each of these sites under a number of conditions, as well as describing muscle glucose uptake in the post-exercise state.

  6. Relation of airway responsiveness to duration of work in a dusty environment.

    PubMed Central

    Ernst, P; Dales, R E; Nunes, F; Becklake, M R

    1989-01-01

    Health selection within a workforce has been found in several industries and appears to be more pronounced in dustier occupations. In this study of airway disease among workers exposed to asbestos and man made mineral fibres, 215 of 246 construction insulators 50 years old or less and currently working in the Montreal area were examined. Spirometry was completed successfully in 214 workers without known asbestosis and 207 underwent methacholine bronchoprovocation testing. Airway responsiveness was expressed as PC15, the concentration of methacholine causing a 15% fall in the forced expiratory volume in one second (FEV1). Exposure to asbestos and synthetic mineral fibre dust was estimated from the total hours of work in the trade since first employment. After the effect of age, height, and pack years of smoking had been taken into account, no relation was found between hours of work and any indices obtained from the forced expiratory manoeuvre (FEV1/FVC, MMF). After the effect of airway calibre (FEV1/FVC), age, and pack years of cigarette consumption had been taken into account, airway responsiveness decreased as the total hours of work in the trade increased. These findings suggest that workers with greater levels of airway responsiveness are more sensitive to exposure in a dusty workplace and in consequence are less likely to continue. In studies of workforces a survivor effect of this nature will tend to weaken the relation between lung function abnormality and occupational exposure. PMID:2648647

  7. ONE AIRWAY: BIOMARKERS OF PROTECTION FROM UPPER AND LOWER AIRWAY INJURY AFTER WORLD TRADE CENTER EXPOSURE

    PubMed Central

    Cho, Soo Jung; Echevarria, Ghislaine C.; Kwon, Sophia; Naveed, Bushra; Schenck, Edward J; Tsukiji, Jun; Rom, William N.; Prezant, David J.; Nolan, Anna; Weiden, Michael D.

    2013-01-01

    Background Firefighters exposed to World Trade Center (WTC) dust have developed chronic rhinosinusitis (CRS) and abnormal forced expiratory volume in 1 second (FEV1). Overlapping but distinct immune responses may be responsible for the clinical manifestations of upper and lower airway injury. We investigated whether a panel of inflammatory cytokines, either associated or not associated with WTC-LI, can predict future chronic rhinosinusitis disease and its severity. Methods Serum obtained within six months of 9/11/2001 from 179 WTC exposed firefighters presenting for subspecialty evaluation prior to 3/2008 was assayed for 39 cytokines. The main outcomes were medically managed CRS (N=62) and more severe CRS cases requiring sinus surgery (N=14). We tested biomarker-CRS severity association using ordinal logistic regression analysis. Results Increasing serum IL-6, IL-8, GRO and neutrophil concentration reduced the risk of CRS progression. Conversely, increasing TNF-α increased the risk of progression. In a multivariable model adjusted for exposure intensity, increasing IL-6, TNF-α and neutrophil concentration remained significant predictors of progression. Elevated IL-6 levels and neutrophil counts also reduced the risk of abnormal FEV1 but in contrast to CRS, increased TNF-α did not increase the risk of abnormal FEV1. Conclusions Our study demonstrates both independent and overlapping biomarker associations with upper and lower respiratory injury, and suggests that the innate immune response may play a protective role against CRS and abnormal lung function in those with WTC exposure. PMID:24290899

  8. Continuous mucociliary transport by primary human airway epithelial cells in vitro

    PubMed Central

    Sears, Patrick R.; Yin, Wei-Ning

    2015-01-01

    Mucociliary clearance (MCC) is an important innate defense mechanism that continuously removes inhaled pathogens and particulates from the airways. Normal MCC is essential for maintaining a healthy respiratory system, and impaired MCC is a feature of many airway diseases, including both genetic (cystic fibrosis, primary ciliary dyskinesia) and acquired (chronic obstructive pulmonary disease, bronchiectasis) disorders. Research into the fundamental processes controlling MCC, therefore, has direct clinical application, but has been limited in part due to the difficulty of studying this complex multicomponent system in vitro. In this study, we have characterized a novel method that allows human airway epithelial cells to differentiate into a mucociliary epithelium that transports mucus in a continuous circular track. The mucociliary transport device allows the measurement and manipulation of all features of mucociliary transport in a controlled in vitro system. In this initial study, the effect of ciliary beat frequency and mucus concentration on the speed of mucociliary transport was investigated. PMID:25979076

  9. Ceylon cinnamon does not affect postprandial plasma glucose or insulin in subjects with impaired glucose tolerance.

    PubMed

    Wickenberg, Jennie; Lindstedt, Sandra; Berntorp, Kerstin; Nilsson, Jan; Hlebowicz, Joanna

    2012-06-01

    Previous studies on healthy subjects have shown that the intake of 6 g Cinnamomum cassia reduces postprandial glucose and that the intake of 3 g C. cassia reduces insulin response, without affecting postprandial glucose concentrations. Coumarin, which may damage the liver, is present in C. cassia, but not in Cinnamomum zeylanicum. The aim of the present study was to study the effect of C. zeylanicum on postprandial concentrations of plasma glucose, insulin, glycaemic index (GI) and insulinaemic index (GII) in subjects with impaired glucose tolerance (IGT). A total of ten subjects with IGT were assessed in a crossover trial. A standard 75 g oral glucose tolerance test (OGTT) was administered together with placebo or C. zeylanicum capsules. Finger-prick capillary blood samples were taken for glucose measurements and venous blood for insulin measurements, before and at 15, 30, 45, 60, 90, 120, 150 and 180 min after the start of the OGTT. The ingestion of 6 g C. zeylanicum had no significant effect on glucose level, insulin response, GI or GII. Ingestion of C. zeylanicum does not affect postprandial plasma glucose or insulin levels in human subjects. The Federal Institute for Risk Assessment in Europe has suggested the replacement of C. cassia by C. zeylanicum or the use of aqueous extracts of C. cassia to lower coumarin exposure. However, the positive effects seen with C. cassia in subjects with poor glycaemic control would then be lost.

  10. A MEMS affinity glucose sensor using a biocompatible glucose-responsive polymer.

    PubMed

    Huang, Xian; Li, Siqi; Schultz, Jerome S; Wang, Qian; Lin, Qiao

    2009-07-16

    We present a MEMS affinity sensor that can potentially allow long-term continuous monitoring of glucose in subcutaneous tissue for diabetes management. The sensing principle is based on detection of viscosity changes due to affinity binding between glucose and poly(acrylamide-ran-3-acrylamidophenylboronic acid) (PAA-ran-PAAPBA), a biocompatible, glucose-specific polymer. The device uses a magnetically driven vibrating microcantilever as a sensing element, which is fabricated from Parylene and situated in a microchamber. A solution of PAA-ran-PAAPBA fills the microchamber, which is separated from the surroundings by a semi-permeable membrane. Glucose permeates through the membrane and binds reversibly to the phenylboronic acid moiety of the polymer. This results in a viscosity change of the sensing solution, which is obtained by measuring the damped cantilever vibration using an optical lever setup, allowing determination of the glucose concentration. Experimental results demonstrate that the device is capable of detecting glucose at physiologically relevant concentrations from 27 mg/dL to 324 mg/dL. The glucose response time constant of the sensor is approximately 3 min, which can be further improved with device design optimization. Excellent reversibility and stability are observed in sensor responses, as highly desired for long-term, stable continuous glucose monitoring. PMID:24511207

  11. Estriol blunts postprandial blood glucose rise in male rats through regulating intestinal glucose transporters.

    PubMed

    Yamabe, Noriko; Kang, Ki Sung; Lee, Woojung; Kim, Su-Nam; Zhu, Bao Ting

    2015-03-01

    Despite increased total food intake in healthy, late-stage pregnant women, their peak postprandial blood sugar levels are normally much lower than the levels seen in healthy nonpregnant women. In this study, we sought to determine whether estriol (E3), an endogenous estrogen predominantly produced during human pregnancy, contributes to the regulation of the postprandial blood glucose level in healthy normal rats. In vivo studies using rats showed that E3 blunted the speed and magnitude of the blood glucose rise following oral glucose administration, but it did not appear to affect the total amount of glucose absorbed. E3 also did not affect insulin secretion, but it significantly reduced the rate of intestinal glucose transport compared with vehicle-treated animals. Consistent with this finding, expression of the sodium-dependent glucose transporter 1 and 2 was significantly downregulated by E3 treatment in the brush-border membrane and basolateral membrane, respectively, of enterocytes. Most of the observed in vivo effects were noticeably stronger with E3 than with 17β-estradiol. Using differentiated human Caco-2 enterocyte monolayer culture as an in vitro model, we confirmed that E3 at physiologically relevant concentrations could directly inhibit glucose uptake via suppression of glucose transporter 2 expression, whereas 17β-estradiol did not have a similar effect. Collectively, these data showed that E3 can blunt the postprandial glycemic surge in rats through modulating the level of intestinal glucose transporters.

  12. Identification of glucose transporters in Aspergillus nidulans.

    PubMed

    Dos Reis, Thaila Fernanda; Menino, João Filipe; Bom, Vinícius Leite Pedro; Brown, Neil Andrew; Colabardini, Ana Cristina; Savoldi, Marcela; Goldman, Maria Helena S; Rodrigues, Fernando; Goldman, Gustavo Henrique

    2013-01-01

    To characterize the mechanisms involved in glucose transport, in the filamentous fungus Aspergillus nidulans, we have identified four glucose transporter encoding genes hxtB-E. We evaluated the ability of hxtB-E to functionally complement the Saccharomyces cerevisiae EBY.VW4000 strain that is unable to grow on glucose, fructose, mannose or galactose as single carbon source. In S. cerevisiae HxtB-E were targeted to the plasma membrane. The expression of HxtB, HxtC and HxtE was able to restore growth on glucose, fructose, mannose or galactose, indicating that these transporters accept multiple sugars as a substrate through an energy dependent process. A tenfold excess of unlabeled maltose, galactose, fructose, and mannose were able to inhibit glucose uptake to different levels (50 to 80 %) in these s. cerevisiae complemented strains. Moreover, experiments with cyanide-m-chlorophenylhydrazone (CCCP), strongly suggest that hxtB, -C, and -E mediate glucose transport via active proton symport. The A. nidulans ΔhxtB, ΔhxtC or ΔhxtE null mutants showed ~2.5-fold reduction in the affinity for glucose, while ΔhxtB and -C also showed a 2-fold reduction in the capacity for glucose uptake. The ΔhxtD mutant had a 7.8-fold reduction in affinity, but a 3-fold increase in the capacity for glucose uptake. However, only the ΔhxtB mutant strain showed a detectable decreased rate of glucose consumption at low concentrations and an increased resistance to 2-deoxyglucose. PMID:24282591

  13. Triptolide inhibits TGF-β1-induced cell proliferation in rat airway smooth muscle cells by suppressing Smad signaling

    SciTech Connect

    Chen, Ming; Lv, Zhiqiang; Huang, Linjie; Zhang, Wei; Lin, Xiaoling; Shi, Jianting; Zhang, Wei; Liang, Ruiyun; Jiang, Shanping

    2015-02-15

    Background: We have reported that triptolide can inhibit airway remodeling in a murine model of asthma via TGF-β1/Smad signaling. In the present study, we aimed to investigate the effect of triptolide on airway smooth muscle cells (ASMCs) proliferation and the possible mechanism. Methods: Rat airway smooth muscle cells were cultured and made synchronized, then pretreated with different concentration of triptolide before stimulated by TGF-β1. Cell proliferation was evaluated by MTT assay. Flow cytometry was used to study the influence of triptolide on cell cycle and apoptosis. Signal proteins (Smad2, Smad3 and Smad7) were detected by western blotting analysis. Results: Triptolide significantly inhibited TGF-β1-induced ASMC proliferation (P<0.05). The cell cycle was blocked at G1/S-interphase by triptolide dose dependently. No pro-apoptotic effects were detected under the concentration of triptolide we used. Western blotting analysis showed TGF-β1 induced Smad2 and Smad3 phosphorylation was inhibited by triptolide pretreatment, and the level of Smad7 was increased by triptolide pretreatment. Conclusions: Triptolide may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation via negative regulation of Smad signaling pathway. - Highlights: • In this study, rat airway smooth muscle cells were cultured and made synchronized. • Triptolide inhibited TGF-β1-induced airway smooth muscle cells proliferation. • Triptolide inhibited ASMCs proliferation via negative regulation of Smad signaling pathway.

  14. Effects of fasting on plasma glucose and prolonged tracer measurement of hepatic glucose output in NIDDM

    SciTech Connect

    Glauber, H.; Wallace, P.; Brechtel, G.

    1987-10-01

    We studied the measurement of hepatic glucose output (HGO) with prolonged (3-/sup 3/H)glucose infusion in 14 patients with non-insulin-dependent diabetes mellitus (NIDDM). Over the course of 10.5 h, plasma glucose concentration fell with fasting by one-third, from 234 +/- 21 to 152 +/- 12 mg/dl, and HGO fell from 2.35 +/- 0.18 to 1.36 +/- 0.07 mg . kg-1 . min-1 (P less than .001). In the basal state, HGO and glucose were significantly correlated (r = 0.68, P = .03), and in individual patients, HGO and glucose were closely correlated as both fell with fasting (mean r = 0.79, P less than .01). Plasma (3-/sup 3/H)glucose radioactivity approached a steady state only 5-6 h after initiation of the primed continuous infusion, and a 20% overestimate of HGO was demonstrated by not allowing sufficient time for tracer labeling of the glucose pool. Assumption of steady-state instead of non-steady-state kinetics in using Steele's equations to calculate glucose turnover resulted in a 9-24% overestimate of HGO. Stimulation of glycogenolysis by glucagon injection demonstrated no incorporation of (3-/sup 3/H)glucose in hepatic glycogen during the prolonged tracer infusion. In a separate study, plasma glucose was maintained at fasting levels (207 +/- 17 mg/dl) for 8 h with the glucose-clamp technique. Total glucose turnover rates remained constant during this prolonged tracer infusion. However, HGO fell to 30% of the basal value simply by maintaining fasting hyperglycemia in the presence of basal insulin levels.

  15. Antioxidant airway responses following experimental exposure to wood smoke in man

    PubMed Central

    2010-01-01

    Background Biomass combustion contributes to the production of ambient particulate matter (PM) in rural environments as well as urban settings, but relatively little is known about the health effects of these emissions. The aim of this study was therefore to characterize airway responses in humans exposed to wood smoke PM under controlled conditions. Nineteen healthy volunteers were exposed to both wood smoke, at a particulate matter (PM2.5) concentration of 224 ± 22 μg/m3, and filtered air for three hours with intermittent exercise. The wood smoke was generated employing an experimental set-up with an adjustable wood pellet boiler system under incomplete combustion. Symptoms, lung function, and exhaled NO were measured over exposures, with bronchoscopy performed 24 h post-exposure for characterisation of airway inflammatory and antioxidant responses in airway lavages. Results Glutathione (GSH) concentrations were enhanced in bronchoalveolar lavage (BAL) after wood smoke exposure vs. air (p = 0.025), together with an increase in upper airway symptoms. Neither lung function, exhaled NO nor systemic nor airway inflammatory parameters in BAL and bronchial mucosal biopsies were significantly affected. Conclusions Exposure of healthy subjects to wood smoke, derived from an experimental wood pellet boiler operating under incomplete combustion conditions with PM emissions dominated by organic matter, caused an increase in mucosal symptoms and GSH in the alveolar respiratory tract lining fluids but no acute airway inflammatory responses. We contend that this response reflects a mobilisation of GSH to the air-lung interface, consistent with a protective adaptation to the investigated wood smoke exposure. PMID:20727160

  16. Detection of Trace Glucose on the Surface of a Semipermeable Membrane Using a Fluorescently Labeled Glucose-Binding Protein: A Promising Approach to Noninvasive Glucose Monitoring

    PubMed Central

    Ge, Xudong; Rao, Govind; Kostov, Yordan; Kanjananimmanont, Sunsanee; Viscardi, Rose M.; Woo, Hyung; Tolosa, Leah

    2013-01-01

    Background Our motivation for this study was to develop a noninvasive glucose sensor for low birth weight neonates. We hypothesized that the underdeveloped skin of neonates will allow for the diffusion of glucose to the surface where it can be sampled noninvasively. On further study, we found that measurable amounts of glucose can also be collected on the skin of adults. Method Cellulose acetate dialysis membrane was used as surrogate for preterm neonatal skin. Glucose on the surface was collected by saline-moistened swabs and analyzed with glucose-binding protein (GBP). The saline-moistened swab was also tested in the neonatal intensive care unit. Saline was directly applied on adult skin and collected for analysis with two methods: GBP and high-performance anion-exchange chromatography (HPAEC). Results The amount of glucose on the membrane surface was found (1) to accumulate with time but gradually level off, (2) to be proportional to the swab dwell time, and (3) the concentration of the glucose solution on the opposite side of the membrane. The swab, however, failed to absorb glucose on neonatal skin. On direct application of saline onto adult skin, we were able to measure by HPAEC and GBP the amount of glucose collected on the surface. Blood glucose appears to track transdermal glucose levels. Conclusions We were able to measure trace amounts of glucose on the skin surface that appear to follow blood glucose levels. The present results show modest correlation with blood glucose. Nonetheless, this method may present a noninvasive alternative to tracking glucose trends. PMID:23439155

  17. Acoustic simulation of a patient's obstructed airway.

    PubMed

    van der Velden, W C P; van Zuijlen, A H; de Jong, A T; Lynch, C T; Hoeve, L J; Bijl, H

    2016-01-01

    This research focuses on the numerical simulation of stridor; a high pitched, abnormal noise, resulting from turbulent airflow and vibrating tissue through a partially obstructed airway. Characteristics of stridor noise are used by medical doctors as indication for location and size of the obstruction. The relation between type of stridor and the various diseases associated with airway obstruction is unclear; therefore, simply listening to stridor is an unreliable diagnostic tool. The overall aim of the study is to better understand the relationship between characteristics of stridor noise and localization and size of the obstruction. Acoustic analysis of stridor may then in future simplify the diagnostic process, and reduce the need for more invasive procedures such as laryngoscopy under general anesthesia. In this paper, the feasibility of a coupled flow, acoustic and structural model is investigated to predict the noise generated by the obstruction as well as the propagation of the noise through the airways, taking into account a one-way coupled fluid, structure, and acoustic interaction components. The flow and acoustic solver are validated on a diaphragm and a simplified airway model. A realistic airway model of a patient suffering from a subglottic stenosis, derived from a real computed tomography scan, is further analyzed. Near the mouth, the broadband noise levels at higher frequencies increased with approximately 15-20 dB comparing the stridorous model with the healthy model, indicating stridorous sound.

  18. Silibinin attenuates allergic airway inflammation in mice

    SciTech Connect

    Choi, Yun Ho; Jin, Guang Yu; Guo, Hui Shu; Piao, Hong Mei; Li, Liang chang; Li, Guang Zhao; Lin, Zhen Hua; Yan, Guang Hai

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Silibinin diminishes ovalbumin-induced inflammatory reactions in the mouse lung. Black-Right-Pointing-Pointer Silibinin reduces the levels of various cytokines into the lung of allergic mice. Black-Right-Pointing-Pointer Silibinin prevents the development of airway hyperresponsiveness in allergic mice. Black-Right-Pointing-Pointer Silibinin suppresses NF-{kappa}B transcriptional activity. -- Abstract: Allergic asthma is a chronic inflammatory disease regulated by coordination of T-helper2 (Th2) type cytokines and inflammatory signal molecules. Silibinin is one of the main flavonoids produced by milk thistle, which is reported to inhibit the inflammatory response by suppressing the nuclear factor-kappa B (NF-{kappa}B) pathway. Because NF-{kappa}B activation plays a pivotal role in the pathogenesis of allergic inflammation, we have investigated the effect of silibinin on a mouse ovalbumin (OVA)-induced asthma model. Airway hyperresponsiveness, cytokines levels, and eosinophilic infiltration were analyzed in bronchoalveolar lavage fluid and lung tissue. Pretreatment of silibinin significantly inhibited airway inflammatory cell recruitment and peribronchiolar inflammation and reduced the production of various cytokines in bronchoalveolar fluid. In addition, silibinin prevented the development of airway hyperresponsiveness and attenuated the OVA challenge-induced NF-{kappa}B activation. These findings indicate that silibinin protects against OVA-induced airway inflammation, at least in part via downregulation of NF-{kappa}B activity. Our data support the utility of silibinin as a potential medicine for the treatment of asthma.

  19. Measles: an epidemic of upper airway obstruction.

    PubMed

    Manning, S C; Ridenour, B; Brown, O E; Squires, J

    1991-09-01

    Between October 1989 and August 1990, Dallas County experienced an 11-month epidemic of measles. Of 995 cases of pediatric measles diagnosed in the outpatient department of Children's Medical Center, 108 patients were admitted and 34 of these demonstrated significant upper airway obstruction at the time of admission. Airway problems ranged from mild inspiratory stridor with nasal flaring to frank obstruction and arrest in the emergency room, requiring intubation. Eight of the 34 airway patients were eventually diagnosed with bacterial tracheitis on the basis of endoscopic findings and culture results. The remaining patients had pictures more consistent with viral laryngotracheitis, but all patients were treated with broad-spectrum antibiotics to prevent possible progression to bacterial tracheitis. A total of nine patients overall required intubation for airway obstruction and all were successfully extubated. Large outbreaks of measles are becoming common again in populations of urban poor--largely unvaccinated children. The disease in these populations tends to occur at a younger age and may be more aggressive with more associated complications. Physicians must keep in mind the possibility of upper airway obstruction in a significant proportion of these patients. Early diagnosis on the basis of clinical signs and symptoms, endoscopy, and radiographs is the key to timely appropriate management.

  20. Acoustic simulation of a patient's obstructed airway.

    PubMed

    van der Velden, W C P; van Zuijlen, A H; de Jong, A T; Lynch, C T; Hoeve, L J; Bijl, H

    2016-01-01

    This research focuses on the numerical simulation of stridor; a high pitched, abnormal noise, resulting from turbulent airflow and vibrating tissue through a partially obstructed airway. Characteristics of stridor noise are used by medical doctors as indication for location and size of the obstruction. The relation between type of stridor and the various diseases associated with airway obstruction is unclear; therefore, simply listening to stridor is an unreliable diagnostic tool. The overall aim of the study is to better understand the relationship between characteristics of stridor noise and localization and size of the obstruction. Acoustic analysis of stridor may then in future simplify the diagnostic process, and reduce the need for more invasive procedures such as laryngoscopy under general anesthesia. In this paper, the feasibility of a coupled flow, acoustic and structural model is investigated to predict the noise generated by the obstruction as well as the propagation of the noise through the airways, taking into account a one-way coupled fluid, structure, and acoustic interaction components. The flow and acoustic solver are validated on a diaphragm and a simplified airway model. A realistic airway model of a patient suffering from a subglottic stenosis, derived from a real computed tomography scan, is further analyzed. Near the mouth, the broadband noise levels at higher frequencies increased with approximately 15-20 dB comparing the stridorous model with the healthy model, indicating stridorous sound. PMID:25567545

  1. Kinins, airway obstruction, and anaphylaxis.

    PubMed

    Kaplan, Allen P

    2010-01-01

    Anaphylaxis is a term that implies symptoms that are present in many organs, some of which are potentially fatal. The pathogenic process can either be IgE-dependent or non-IgE-dependent; the latter circumstance may be referred to as anaphylactoid. Bradykinin is frequently responsible for the manifestations of IgE-independent reactions. Blood levels may increase because of overproduction; diseases such as the various forms of C1 inhibitor deficiency (hereditary or acquired) or hereditary angioedema with normal C1 inhibitor are examples in this category. Blood levels may also increase because of an abnormality in bradykinin metabolism; the angioedema due to ACE inhibitors is a commonly encountered example. Angioedema due to bradykinin has the potential to cause airway obstruction and asphyxia as well as severe gastrointestinal symptoms simulating an acute abdomen. Formation of bradykinin in plasma is a result of a complex interaction among proteins such as factor XII, prekallikrein, and high molecular weight kininogen (HK) resulting in HK cleavage and liberation of bradykinin. These proteins also assemble along the surface of endothelial cells via zinc-dependent interactions with gC1qR, cytokeratin 1, and u-PAR. Endothelial cell expression (or secretion) of heat-shock protein 90 or prolylcarboxypeptidase can activate the prekallikrein-HK complex to generate bradykinin in the absence of factor XII, however factor XII is then secondarily activated by the kallikrein that results. Bradykinin is destroyed by carboxypeptidase N and angiotensin-converting enzyme. The hypotension associated with IgE-dependent anaphylaxis maybe mediated, in part, by massive proteolytic digestion of HK by kallikreins (tissue or plasma-derived) or other cell-derived kininogenases. PMID:20519882

  2. Sputum Leucine-Rich Alpha-2 Glycoprotein as a Marker of Airway Inflammation in Asthma

    PubMed Central

    Honda, Hiromi; Fujimoto, Minoru; Miyamoto, Shintaro; Ishikawa, Nobuhisa; Serada, Satoshi; Hattori, Noboru; Nomura, Shintaro; Kohno, Nobuoki; Yokoyama, Akihito; Naka, Tetsuji

    2016-01-01

    Background Asthma is a chronic inflammatory disease of airways, but an ideal biomarker that accurately reflects ongoing airway inflammation has not yet been established. The aim of this study was to examine the potential of sputum leucine-rich alpha-2 glycoprotein (LRG) as a new biomarker for airway inflammation in asthma. Methods We obtained induced sputum samples from patients with asthma (N = 64) and healthy volunteers (N = 22) and measured LRG concentration by sandwich enzyme-linked immunosorbent assay (ELISA). Ovalbumin (OVA)-induced asthma model mice were used to investigate the mechanism of LRG production during airway inflammation. The LRG concentrations in the bronchoalveolar lavage fluid (BALF) obtained from mice were determined by ELISA and mouse lung sections were stained with anti-LRG antibody and periodic acid-Schiff (PAS) reagent. Results Sputum LRG concentrations were significantly higher in patients with asthma than in healthy volunteers (p = 0.00686). Consistent with patients’ data, BALF LRG levels in asthma model mice were significantly higher than in control mice (p = 0.00013). Immunohistochemistry of lung sections from asthma model mice revealed that LRG was intensely expressed in a subpopulation of bronchial epithelial cells, which corresponded with PAS-positive mucus producing cells. Conclusion These findings suggest that sputum LRG is a promising biomarker of local inflammation in asthma. PMID:27611322

  3. Identification of Glycosaminoglycans in Human Airway Secretions

    PubMed Central

    Monzon, Maria E.; Casalino-Matsuda, Susana M.; Forteza, Rosanna M.

    2006-01-01

    Glycosaminoglycans (GAGs), known to be present in airway mucus, are macromolecules with a variety of structural and biological functions. In the present work, we used fluorophore-assisted carbohydrate electrophoresis (FACE) to identify and relatively quantify GAGs in human tracheal aspirates (HTA) obtained from healthy volunteers. Primary cultures of normal human bronchial epithelial (NHBE) and submucosal gland (SMG) cells were used to assess their differential contribution to GAGs in mucus. Distribution was further assessed by immunofluorescence in human trachea tissue sections and in cell cultures. HTA samples contained keratan sulfate (KS), chondroitin/dermatan sulfate (CS/DS), and hyaluronan (HA), whereas heparan sulfate (HS) was not detected. SMG cultures secreted CS/DS and HA, CS/DS being the most abundant GAGs in these cultures. NHBE cells synthesized KS, HA, and CS/DS. Confocal microscopy showed that KS was exclusively found at the apical border of NHBE cells and on the apical surface of ciliated epithelial cells in tracheal tissues. CS/DS and HA were present in both NHBE and SMG cells. HS was only found in the extracellular matrix in trachea tissue sections. In summary, HTA samples contain KS, CS/DS, and HA, mirroring a mixture of secretions originated in surface epithelial cells and SMGs. We conclude that surface epithelium is responsible for most HA and all KS present in secretions, whereas glands secrete most of CS/DS. These data suggest that, in diseases where the contribution to secretions of glands versus epithelial cells is altered, the relative concentration of individual GAGs, and therefore their biological activities, will also be affected. PMID:16195536

  4. Effects of ozone on airway epithelial permeability and ion transport.

    PubMed

    Bromberg, P A; Ranga, V; Stutts, M J

    1991-12-01

    Ozone is a highly reactive form of oxygen produced in the atmosphere by photochemical reactions involving substrates emitted from automobile engines. Outdoor air concentrations as high as 0.4 parts per million (ppm) occur. The respiratory tract extracts about 90% of inhaled ozone. From the chemical reactivity of ozone, it is expected to attack organic molecules located on or near the respiratory surfaces. The airways are covered with a cohesive layer of epithelial cells that forms the boundary between the external environment and the respiratory tissues. One important role of this epithelial layer is its barrier function. Airborne particles that deposit (and dissolve) in the airway surface liquid are not readily absorbed, and soluble tissue components are excluded from the surface liquid. The epithelium also controls the volume and composition of the surface liquid. One important process in this regard is the absorption and secretion of ions and water. We have studied the effects of inhalation of ozone on the barrier function (permeability to dissolved molecules) and the ion transport activity of epithelium using both in vivo and in vitro techniques. All our experiments were performed with male Hartley strain guinea pigs. Conscious, unrestrained animals were exposed to a concentration of ozone of 1 ppm for three hours in controlled environmental chambers in the Health Effects Research Laboratory, U.S. Environmental Protection Agency (EPA), Research Triangle Park, NC. Such exposures caused a marked increase in the rate of appearance in blood of various water-soluble compounds instilled onto the surface of the trachea, indicating increased permeability of the airway epithelium. This interpretation was supported by electron microscopy, which showed that the tracer molecule horseradish peroxidase was present in the intercellular spaces of tracheal epithelium from ozone-exposed, but not air-exposed (control), animals. However, when the tracheas were excised after ozone

  5. Concentrated arabinoxylan in wheat bread has beneficial effects as rye breads on glucose and changes in gene expressions in insulin-sensitive tissues of Zucker diabetic fatty (ZDF) rats.

    PubMed

    Hartvigsen, Merete Lindberg; Jeppesen, Per Bendix; Lærke, Helle Nygaard; Njabe, Elvis Ngande; Knudsen, Knud Erik Bach; Hermansen, Kjeld

    2013-05-29

    The health-promoting effects of dietary fiber may vary with content, structure, and composition in the diet. The aim was to study how low-fiber wheat bread (WB), wheat bread supplemented with wheat arabinoxylan (AX) or oat β-glucan (BG), whole meal rye bread (RM), and rye bread with kernels (RK) affected central parameters of glucose and lipid metabolism and gene changes of Zucker diabetic fatty rats. Blood glucose response areas after an oral glucose tolerance test were significantly lower after AX (mean ± SEM; 2117 ± 170 mmol/L·180 min), RM (1978 ± 206 mmol/L·180 min), and RK (2234 ± 262 mmol/L·180 min) breads than after WB (3586 ± 100 mmol/L·180 min; p < 0.0001). AX, RK, and RM changed expressions of adipose GAPDH, AMPK, FAS, SREBP-1c, and hepatic PCG-1α, whereas BG had similar effects as WB. Thus, arabinoxylan added to wheat bread had beneficial effects on glycemic control as whole grain rye bread in this animal model. PMID:23656567

  6. A fluorescence polarization based assay for glucose sensing

    NASA Astrophysics Data System (ADS)

    Cummins, Brian M.; Coté, Gerard L.

    2012-03-01

    A fluorescence polarization (FP) assay was developed to determine concentrations of glucose using concanavalin A (ConA) and fluorescently-labeled dextran. Predictive FP responses to glucose were elicited for different assay configurations using mathematical modeling and displayed herein. Using 4 kDa FITC-dextran, we predicted a change of 0.120 P units from 0 mg/dL glucose to 500 mg/dL. This shows the potential that a homogenous, reproducible FP assay can be engineered to measure glucose concentrations using tetrameric ConA and 4k kDa FITC-dextran.

  7. Noninvasive glucose sensing by transcutaneous Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Shih, Wei-Chuan; Bechtel, Kate L.; Rebec, Mihailo V.

    2015-05-01

    We present the development of a transcutaneous Raman spectroscopy system and analysis algorithm for noninvasive glucose sensing. The instrument and algorithm were tested in a preclinical study in which a dog model was used. To achieve a robust glucose test system, the blood levels were clamped for periods of up to 45 min. Glucose clamping and rise/fall patterns have been achieved by injecting glucose and insulin into the ear veins of the dog. Venous blood samples were drawn every 5 min and a plasma glucose concentration was obtained and used to maintain the clamps, to build the calibration model, and to evaluate the performance of the system. We evaluated the utility of the simultaneously acquired Raman spectra to be used to determine the plasma glucose values during the 8-h experiment. We obtained prediction errors in the range of ˜1.5-2 mM. These were in-line with a best-case theoretical estimate considering the limitations of the signal-to-noise ratio estimates. As expected, the transition regions of the clamp study produced larger predictive errors than the stable regions. This is related to the divergence of the interstitial fluid (ISF) and plasma glucose values during those periods. Two key contributors to error beside the ISF/plasma difference were photobleaching and detector drift. The study demonstrated the potential of Raman spectroscopy in noninvasive applications and provides areas where the technology can be improved in future studies.

  8. Noninvasive glucose sensing by transcutaneous Raman spectroscopy

    PubMed Central

    Shih, Wei-Chuan; Bechtel, Kate L.; Rebec, Mihailo V.

    2015-01-01

    Abstract. We present the development of a transcutaneous Raman spectroscopy system and analysis algorithm for noninvasive glucose sensing. The instrument and algorithm were tested in a preclinical study in which a dog model was used. To achieve a robust glucose test system, the blood levels were clamped for periods of up to 45 min. Glucose clamping and rise/fall patterns have been achieved by injecting glucose and insulin into the ear veins of the dog. Venous blood samples were drawn every 5 min and a plasma glucose concentration was obtained and used to maintain the clamps, to build the calibration model, and to evaluate the performance of the system. We evaluated the utility of the simultaneously acquired Raman spectra to be used to determine the plasma glucose values during the 8-h experiment. We obtained prediction errors in the range of ∼1.5−2  mM. These were in-line with a best-case theoretical estimate considering the limitations of the signal-to-noise ratio estimates. As expected, the transition regions of the clamp study produced larger predictive errors than the stable regions. This is related to the divergence of the interstitial fluid (ISF) and plasma glucose values during those periods. Two key contributors to error beside the ISF/plasma difference were photobleaching and detector drift. The study demonstrated the potential of Raman spectroscopy in noninvasive applications and provides areas where the technology can be improved in future studies. PMID:25688542

  9. Critical Care Glucose Point-of-Care Testing.

    PubMed

    Narla, S N; Jones, M; Hermayer, K L; Zhu, Y

    2016-01-01

    Maintaining blood glucose concentration within an acceptable range is a goal for patients with diabetes mellitus. Point-of-care glucose meters initially designed for home self-monitoring in patients with diabetes have been widely used in the hospital settings because of ease of use and quick reporting of blood glucose information. They are not only utilized for the general inpatient population but also for critically ill patients. Many factors affect the accuracy of point-of-care glucose testing, particularly in critical care settings. Inaccurate blood glucose information can result in unsafe insulin delivery which causes poor glucose control and can be fatal. Healthcare professionals should be aware of the limitations of point-of-care glucose testing. This chapter will first introduce glucose regulation in diabetes mellitus, hyperglycemia/hypoglycemia in the intensive care unit, importance of glucose control in critical care patients, and pathophysiological variables of critically ill patients that affect the accuracy of point-of-care glucose testing. Then, we will discuss currently available point-of-care glucose meters and preanalytical, analytical, and postanalytical sources of variation and error in point-of-care glucose testing. PMID:27645817

  10. Glucose: detection and analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glucose is an aldosic monosaccharide that is centrally entrenched in the processes of photosynthesis and respiration, serving as an energy reserve and metabolic fuel in most organisms. As both a monomer and as part of more complex structures such as polysaccharides and glucosides, glucose also pla...

  11. Monitor blood glucose - slideshow

    MedlinePlus

    ... medlineplus.gov/ency/presentations/100220.htm Monitoring blood glucose - Series—Monitoring blood glucose: Using a self-test meter To use the ... A.M. Editorial team. Related MedlinePlus Health Topics Blood Sugar A.D.A.M., Inc. is accredited by ...

  12. SPONTANEOUS AIRWAY HYPERRESPONSIVENESS IN ESTROGEN RECEPTOR-A DEFICIENT MICE

    EPA Science Inventory

    Rationale: Airway hyperresponsiveness is a critical feature of asthma. Substantial epidemiologic evidence supports a role for female sex hormones in modulating lung function and airway hyperresponsiveness in humans. Objectives: To examine the role of estrogen receptors in modulat...

  13. Laser applications in pediatric airway surgery

    NASA Astrophysics Data System (ADS)

    Karamzadeh, Amir M.; Ahuja, Gurpreet S.; Nguyen, John D.; Crumley, Roger

    2003-06-01

    The smaller anatomy and limited access to instrumentation pose a challenge to the pediatric airway surgeon. The enhanced precision and ability to photocoagulate tissue while operating with the laser enhances the surgeon"s ability to successfully treat unique pediatric conditions such subglottic hemangiomas, congenital cysts, respiratory papillomatosis, and laryngeal or tracheal stenosis. Due to its shallow tissue penetration and thermal effect, the carbon dioxide (CO2) laser is generally considered the laser of choice for pediatric airway applications. The potential for increased scarring and damage to underlying tissue caused by the greater penetration depth and thermal effect of the Nd:YAG and KTP lasers preclude their use in this population. In this review, we will describe the specific advantages of using lasers in airway surgery, the current technology and where the current technology is deficient.

  14. Airway Management in Croup and Epiglottitis

    PubMed Central

    Crumley, Roger L.

    1977-01-01

    Treatment techniques for airway obstruction in croup and epiglottitis are reviewed in the medical literature. Series totaling 295 nasotracheal intubations, and 591 tracheostomies were reviewed. There were two deaths attributable to airway complications in 126 patients in whom nasotracheal intubation was carried out. In three patients subglottic granulation tissue and subglottic stenoses developed from short-term nasotracheal intubation. There were no subglottic stenoses or tracheal stenoses reported in the 591 tracheostomies. From this review, it would seem feasible to use nasotracheal intubation for short-term airway treatment in croup and epiglottitis. The increasing occurrence of laryngeal and tracheal complications with long-term intubation suggests that tracheostomy be considered in such cases. PMID:349884

  15. MicroRNA in United Airway Diseases

    PubMed Central

    Liu, Zheng; Zhang, Xin-Hao; Callejas-Díaz, Borja; Mullol, Joaquim

    2016-01-01

    The concept of united airway diseases (UAD) has received increasing attention in recent years. Sustained and increased inflammation is a common feature of UAD, which is inevitably accompanied with marked gene modification and tight gene regulation. However, gene regulation in the common inflammatory processes in UAD remains unclear. MicroRNA (miRNA), a novel regulator of gene expression, has been considered to be involved in many inflammatory diseases. Although there are an increasing number of studies of miRNAs in inflammatory upper and lower airway diseases, few miRNAs have been identified that directly link the upper and lower airways. In this article, therefore, we reviewed the relevant studies available in order to improve the understanding of the roles of miRNAs in the interaction and pathogenesis of UAD. PMID:27187364

  16. Effect of Perinatal secondhand tobacco smoke exposure on in vivo and intrinsic airway structure/function in non-human primates

    SciTech Connect

    Joad, Jesse P. Kott, Kayleen S.; Bric, John M.; Peake, Janice L.; Pinkerton, Kent E.

    2009-02-01

    Infants exposed to second hand smoke (SHS) experience more problems with wheezing. This study was designed to determine if perinatal SHS exposure increases intrinsic and/or in vivo airway responsiveness to methacholine and whether potential structural/cellular alterations in the airway might explain the change in responsiveness. Pregnant rhesus monkeys were exposed to filtered air (FA) or SHS (1 mg/m{sup 3} total suspended particulates) for 6 h/day, 5 days/week starting at 50 days gestational age. The mother/infant pairs continued the SHS exposures postnatally. At 3 months of age each infant: 1) had in vivo lung function measurements in response to inhaled methacholine, or 2) the right accessory lobe filled with agarose, precision-cut to 600 {mu}m slices, and bathed in increasing concentrations of methacholine. The lumenal area of the central airway was determined using videomicrometry followed by fixation and histology with morphometry. In vivo tests showed that perinatal SHS increases baseline respiratory rate and decreases responsiveness to methacholine. Perinatal SHS did not alter intrinsic airway responsiveness in the bronchi. However in respiratory bronchioles, SHS exposure increased airway responsiveness at lower methacholine concentrations but decreased it at higher concentrations. Perinatal SHS did not change eosinophil profiles, epithelial volume, smooth muscle volume, or mucin volume. However it did increase the number of alveolar attachments in bronchi and respiratory bronchioles. In general, as mucin increased, airway responsiveness decreased. We conclude that perinatal SHS exposure alters in vivo and intrinsic airway responsiveness, and alveolar attachments.

  17. Effect of perinatal secondhand tobacco smoke exposure on in vivo and intrinsic airway structure/function in non-human primates.

    PubMed

    Joad, Jesse P; Kott, Kayleen S; Bric, John M; Peake, Janice L; Pinkerton, Kent E

    2009-02-01

    Infants exposed to second hand smoke (SHS) experience more problems with wheezing. This study was designed to determine if perinatal SHS exposure increases intrinsic and/or in vivo airway responsiveness to methacholine and whether potential structural/cellular alterations in the airway might explain the change in responsiveness. Pregnant rhesus monkeys were exposed to filtered air (FA) or SHS (1 mg/m(3) total suspended particulates) for 6 h/day, 5 days/week starting at 50 days gestational age. The mother/infant pairs continued the SHS exposures postnatally. At 3 months of age each infant: 1) had in vivo lung function measurements in response to inhaled methacholine, or 2) the right accessory lobe filled with agarose, precision-cut to 600 mum slices, and bathed in increasing concentrations of methacholine. The lumenal area of the central airway was determined using videomicrometry followed by fixation and histology with morphometry. In vivo tests showed that perinatal SHS increases baseline respiratory rate and decreases responsiveness to methacholine. Perinatal SHS did not alter intrinsic airway responsiveness in the bronchi. However in respiratory bronchioles, SHS exposure increased airway responsiveness at lower methacholine concentrations but decreased it at higher concentrations. Perinatal SHS did not change eosinophil profiles, epithelial volume, smooth muscle volume, or mucin volume. However it did increase the number of alveolar attachments in bronchi and respiratory bronchioles. In general, as mucin increased, airway responsiveness decreased. We conclude that perinatal SHS exposure alters in vivo and intrinsic airway responsiveness, and alveolar attachments. PMID:19084550

  18. Glucose-lowering effects of intestinal bile acid sequestration through enhancement of splanchnic glucose utilization.

    PubMed

    Prawitt, Janne; Caron, Sandrine; Staels, Bart

    2014-05-01

    Intestinal bile acid (BA) sequestration efficiently lowers plasma glucose concentrations in type 2 diabetes (T2D) patients. Because BAs act as signaling molecules via receptors, including the G protein-coupled receptor TGR5 and the nuclear receptor FXR (farnesoid X receptor), to regulate glucose homeostasis, BA sequestration, which interrupts the entero-hepatic circulation of BAs, constitutes a plausible action mechanism of BA sequestrants. An increase of intestinal L-cell glucagon-like peptide-1 (GLP-1) secretion upon TGR5 activation is the most commonly proposed mechanism, but recent studies also argue for a direct entero-hepatic action to enhance glucose utilization. We discuss here recent findings on the mechanisms of sequestrant-mediated glucose lowering via an increase of splanchnic glucose utilization through entero-hepatic FXR signaling.

  19. Glucose as substrate and signal in priming: Results from experiments with non-metabolizable glucose analogues

    NASA Astrophysics Data System (ADS)

    Mason-Jones, Kyle; Kuzyakov, Yakov

    2016-04-01

    Priming of soil organic matter remains the subject of intense research, but a mechanistic explanation of the phenomenon remains to be demonstrated. This is largely due to the multiple effects of easily available carbon on the soil microbial community, and the challenge of separating these influences from one another. Several glucose analogues can be taken up by microbial glucose transporters and have similar regulatory effects on metabolism. These substances are, however, not easily catabolized by the common glycolytic pathway, limiting their energy value. Therefore, they can be used to distinguish between the action of glucose as a metabolic signal, and its influence as an energy source. We incubated an agricultural Haplic Luvisol under controlled conditions for 24 days after addition of: 1) glucose, 2) 3-O-methyl-glucose, 3) α-methylglucoside or 4) 2-deoxyglucose, at three concentration levels, along with a control treatment of water addition. CO2 efflux from soil was monitored by trapping evolved CO2 in NaOH and back-titration with HCl. On the first day after amendment, CO2 efflux from soil increased strongly for glucose and much less for the analogues, relative to the control. Only glucose caused a peak in efflux within the first two days. Peak mineralization of 2-deoxyglucose and α-methylglucoside was delayed until the third day, while CO2 from 3-O-methyl-glucose increased gradually, with a peak delayed by approximately a week. For glucose, the immediate increase in respiration was strongly dependent on the amount of glucose added, but this was not the case for the analogues, indicating that the catabolic potential for these substances was saturated. This is consistent with only a small part of the microbial community being capable of utilizing these carbon sources. In a subsequent experiment, 14C-labelled glucose or 14C-labelled 3-O-methyl-glucose were added to the same soil, enabling quantification of the priming effect. For 3-O-methyl-glucose, priming was

  20. Construction of near-infrared photonic crystal glucose-sensing materials for ratiometric sensing of glucose in tears.

    PubMed

    Hu, Yumei; Jiang, Xiaomei; Zhang, Laiying; Fan, Jiao; Wu, Weitai

    2013-10-15

    Noninvasive monitoring of glucose in tears is highly desirable in tight glucose control. The polymerized crystalline colloidal array (PCCA) that can be incorporated into contact lens represents one of the most promising materials for noninvasive monitoring of glucose in tears. However, low sensitivity and slow time response of the PCCA reported in previous arts has limited its clinical utility. This paper presents a new PCCA, denoted as NIR-PCCA, comprising a CCA of glucose-responsive sub-micrometered poly(styrene-co-acrylamide-co-3-acrylamidophenylboronic acid) microgels embedded within a slightly positive charged hydrogel matrix of poly(acrylamide-co-2-(dimethylamino)ethyl acrylate). This newly designed NIR-PCCA can reflect near-infrared (NIR) light, whose intensity (at 1722 nm) would decrease evidently with increasing glucose concentration over the physiologically relevant range in tears. The lowest glucose concentration reliably detectable was as low as ca. 6.1 μg/dL. The characteristic response time τ(sensing) was 22.1±0.2s when adding glucose to 7.5 mg/dL, and the higher the glucose concentration is, the faster the time response. Such a rationally designed NIR-PCCA is well suited for ratiometric NIR sensing of tear glucose under physiological conditions, thereby likely to bring this promising glucose-sensing material to the forefront of analytical devices for diabetes.

  1. Mitogen-stimulated and rapamycin-sensitive glucose transporter 12 targeting and functional glucose transport in renal epithelial cells.

    PubMed

    Wilson-O'Brien, Amy L; Dehaan, Carrie L; Rogers, Suzanne

    2008-03-01

    We hypothesized that glucose transporter 12 (GLUT12) is involved in regulation of glucose flux in distal renal tubules in response to elevated glucose. We used the Madin-Darby canine kidney polarized epithelial cell model and neutralizing antibodies to analyze GLUT12 targeting and directional GLUT12-mediated glucose transport. At physiological glucose concentrations, GLUT12 was localized to a perinuclear position. High glucose and serum treatment resulted in GLUT12 localization to the apical membrane. This mitogen-stimulated targeting of GLUT12 was inhibited by rapamycin, the specific inhibitor of mammalian target of rapamycin (mTOR). The functional role of GLUT12 was also examined. We constructed a GLUT12 cDNA containing a c-Myc epitope tag in the fifth exofacial loop. Assays of glucose transport at the apical membrane were performed using Transwell filters. By comparing transport assays in the presence of neutralizing anti-c-Myc monoclonal antibody, we specifically measured GLUT12-mediated glucose transport at the apical surface. GLUT12-mediated glucose transport was mitogen dependent and rapamycin sensitive. Our results implicate mTOR signaling in a novel pathway of glucose transporter protein targeting and glucose transport. Activity of the mTOR pathway has been associated with diabetic kidney disease. Our results provide evidence for a link between GLUT12 protein trafficking, glucose transport and signaling molecules central to the control of metabolic disease processes. PMID:18039784

  2. [Modern airway management--current concepts for more patient safety].

    PubMed

    Timmermann, Arnd

    2009-04-01

    Effective and safe airway management is one of the core skills among anaesthesiologists and all physicians involved in acute care medicine. However, failure in airway management is still the most frequent single incidence with the highest impact on patient's morbidity and mortality known from closed claims analyses. The anaesthesiologist has to manage the airway in elective patients providing a high level of safety with as little airway injury and interference with the cardio-vascular system as possible. Clinical competence also includes the management of the expected and unexpected difficult airway in different clinical environments. Therefore, it is the anaesthesiologist's responsibility not only to educate and train younger residents, but also all kinds of medical personnel involved in airway management, e.g. emergency physicians, intensive care therapists or paramedics. Modern airway devices, strategies and educational considerations must fulfill these sometimes diverse and large range requirements. Supraglottic airway devices will be used more often in the daily clinical routine. This is not only due the multiple advantages of these devices compared to the tracheal tube, but also because of the new features of some supraglottic airways, which separate the airway from the gastric track and give information of the pharyngeal position. For the event of a difficult airway, new airway devices and concepts should be trained and applied in daily practice.

  3. 21 CFR 868.2600 - Airway pressure monitor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Airway pressure monitor. 868.2600 Section 868.2600...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2600 Airway pressure monitor. (a) Identification. An airway pressure monitor is a device used to measure the pressure in a patient's upper...

  4. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  5. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  6. 21 CFR 868.2600 - Airway pressure monitor.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Airway pressure monitor. 868.2600 Section 868.2600...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2600 Airway pressure monitor. (a) Identification. An airway pressure monitor is a device used to measure the pressure in a patient's upper...

  7. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  8. 21 CFR 868.2600 - Airway pressure monitor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Airway pressure monitor. 868.2600 Section 868.2600...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2600 Airway pressure monitor. (a) Identification. An airway pressure monitor is a device used to measure the pressure in a patient's upper...

  9. 21 CFR 868.2600 - Airway pressure monitor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Airway pressure monitor. 868.2600 Section 868.2600...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2600 Airway pressure monitor. (a) Identification. An airway pressure monitor is a device used to measure the pressure in a patient's upper...

  10. 21 CFR 868.2600 - Airway pressure monitor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Airway pressure monitor. 868.2600 Section 868.2600...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2600 Airway pressure monitor. (a) Identification. An airway pressure monitor is a device used to measure the pressure in a patient's upper...

  11. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  12. 21 CFR 868.1780 - Inspiratory airway pressure meter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Inspiratory airway pressure meter. 868.1780... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1780 Inspiratory airway pressure meter. (a) Identification. An inspiratory airway pressure meter is a device used to measure the...

  13. New scheme for polarimetric glucose sensing without polarizers

    NASA Astrophysics Data System (ADS)

    Winkler, Amy M.; Bonnema, Garret T.; Barton, Jennifer K.

    2010-02-01

    Polarimetric glucose sensing is a promising method for noninvasive estimation of blood glucose concentration. Published methods of polarimetric glucose sensing generally rely on measuring the rotation of light as it traverses the aqueous humor of the eye. In this article, an interferometer is described that can detect polarization changes due to glucose without the use of polarization control or polarization analyzing elements. Without polarizers, this system is sensitive to optical activity, inherent to glucose, but minimally sensitive to linear retardance, inherent to the cornea. The underlying principle of the system was experimentally verified using spectral domain optical coherence tomography. A detection scheme involving amplitude modulation was simulated, demonstrating sensitivity to clinically relevant glucose concentrations and an acceptable error due to time varying linear birefringence of the cornea using Clarke Error Grid Analysis.

  14. Soluble mediators, not cilia, determine airway surface liquid volume in normal and cystic fibrosis superficial airway epithelia.

    PubMed

    Tarran, Robert; Trout, Laura; Donaldson, Scott H; Boucher, Richard C

    2006-05-01

    A key aspect of the lung's innate defense system is the ability of the superficial epithelium to regulate airway surface liquid (ASL) volume to maintain a 7-mum periciliary liquid layer (PCL), which is required for cilia to beat and produce mucus flow. The mechanisms whereby airway epithelia regulate ASL height to >or=7 microm are poorly understood. Using bumetanide as an inhibitor of Cl- secretion, and nystatin as an activator of Na+ absorption, we found that a coordinated "blending" of both Cl- secretion and Na+ absorption must occur to effect ASL volume homeostasis. We then investigated how ASL volume status is regulated by the underlying epithelia. Cilia were not critical to this process as (a) ASL volume was normal in cultures from patients with primary ciliary dyskinesia with immotile cilia, and (b) in normal cultures that had not yet undergone ciliogenesis. However, we found that maneuvers that mimic deposition of excess ASL onto the proximal airways, which occurs during mucociliary clearance and after glandular secretion, acutely stimulated Na+ absorption, suggesting that volume regulation was sensitive to changes in concentrations of soluble mediators in the ASL rather than alterations in ciliary beating. To investigate this hypothesis further, we added potential "soluble mediators" to the ASL. ASL volume regulation was sensitive to a channel-activating protein (CAP; trypsin) and a CAP inhibitor (aprotinin), which regulated Na+ absorption via changes in epithelial Na+ channel (ENaC) activity in both normal and cystic fibrosis cultures. ATP was also found to acutely regulate ASL volume by inducing secretion in normal and cystic fibrosis (CF) cultures, while its metabolite adenosine (ADO) evoked secretion in normal cultures but stimulated absorption in CF cultures. Interestingly, the amount of ASL/Cl- secretion elicited by ATP/ADO was influenced by the level of CAP-induced Na+ absorption, suggesting that there are important interactions between the soluble

  15. Characterization of the intravenous glucose tolerance test and the combined glucose-insulin test in donkeys.

    PubMed

    Mendoza, F J; Aguilera-Aguilera, R; Gonzalez-De Cara, C A; Toribio, R E; Estepa, J C; Perez-Ecija, A

    2015-12-01

    Glucose-insulin dynamic challenges such as the intravenous glucose tolerance test (IVGTT) and combined glucose-insulin test (CGIT) have not been described in donkeys. The objectives of this study were (1) to characterize the IVGTT and CGIT in healthy adult donkeys, and (2) to establish normal glucose-insulin proxies. Sixteen donkeys were used and body morphometric variables obtained each. For the IVGTT, glucose (300 mg/kg) was given IV. For the CGIT, glucose (150 mg/kg) followed by recombinant insulin (0.1 IU/kg) were administered IV. Blood samples for glucose and insulin determinations were collected over 300 min. In the IVGTT the positive phase lasted 160.9 ± 13.3 min, glucose concentration peaked at 323.1 ± 9.2 mg/dL and declined at a rate of 1.28 ± 0.15 mg/dL/min. The glucose area under the curve (AUC) was 21.4 ± 1.9 × 10(3) mg/dL/min and the insulin AUC was 7.2 ± 0.9 × 10(3) µIU/mL/min. The positive phase of the CGIT curve lasted 44 ± 3 min, with a glucose clearance rate of 2.01 ± 0.18 mg/dL/min. The negative phase lasted 255.9 ± 3 min, decreasing glucose concentration at rate of -0.63 ± 0.06 mg/dL/min, and reaching a nadir (33.1 ± 3.6 mg/dL) at 118.3 ± 6.3 min. The glucose and insulin AUC values were 15.2 ± 0.9 × 10(3) mg/dL/min and 13.2 ± 0.9 × 10(3) µIU/mL/min. This is the first study characterizing CGIT and IVGTT, and glucose-insulin proxies in healthy adult donkeys. Distinct glucose dynamics, when compared with horses, support the use of species-specific protocols to assess endocrine function.

  16. Noninvasive blood glucose monitoring with laser diode

    NASA Astrophysics Data System (ADS)

    Zhang, Xiqin; Chen, Jianhong; Ooi, Ean Tat; Yeo, Joon Hock

    2006-02-01

    The non-invasive measurement of blood sugar level was studied by use of near infrared laser diodes. The in vitro and in vivo experiments were carried out using six laser diodes having wavelengths range from 1550 nm to 1750nm. Several volunteers were tested for OGTT (Oral Glucose Tolerance Test) experiment. We took blood from a fingertip and measured its concentration with a glucose meter while taking signal voltage from laser diodes system. The data of signal voltage were processed to do calibration and prediction; in this paper PLS (Partial Least Square) method was used to do modeling. For in vitro experiment, good linear relationship between predicted glucose concentration and real glucose concentration was obtained. For in vivo experiments, we got the blood sugar level distributions in Clarke error grid that is a reference for doctors to do diagnosis and treatment. In the Clarke error grid, 75% of all data was in area A and 25 % was in area B. From the in vitro and in vivo results we know that multiple laser diodes are suitable for non-invasive blood glucose monitoring.

  17. Inhaled ethanol potentiates the cough response to capsaicin in patients with airway sensory hyperreactivity.

    PubMed

    Millqvist, Eva; Ternesten-Hasséus, Ewa; Bende, Mats

    2008-10-01

    A suggested explanation for airway symptoms induced by chemicals and scents is sensory hyperreactivity (SHR) of airway mucosal nerves. Patients with SHR have increased cough sensitivity to inhaled capsaicin, mediated by transient receptor potential (TRP) ion channels. In animal experiments, some TRP receptors are potentiated by ethanol, which is why in this study, the aim was to evaluate whether a pre-inhalation of ethanol could influence the capsaicin cough response in patients with SHR. Fifteen patients with SHR and 15 healthy controls were provoked on three occasions with two concentrations of inhaled capsaicin. Before each capsaicin provocation, a pre-inhalation of saline or one of two concentrations of ethanol was given in a double-blind, randomized fashion. The participants reacted in a dose-dependent way with cough on the capsaicin inhalations. Among the patients, but not in the control group, pre-inhalation of ethanol increased the cough response dose-dependently. The results suggest that the pathophysiology of SHR is related to airway mucosal TRP receptors in the sensory nerves. In scented products, the combination of ethanol as a solvent and perfume may augment an airway reaction in sensitive individuals.

  18. The antidiabetic agent glibenclamide protects airway hyperresponsiveness and inflammation in mice.

    PubMed

    Cui, Wei; Zhang, Shufang; Cai, Zhijian; Hu, Xinlei; Zhang, Ruifeng; Wang, Yong; Li, Na; Chen, Zhihua; Zhang, Gensheng

    2015-04-01

    Glibenclamide has a newly discovered role in inflammation regulation besides its antidiabetic effect. As an inhibitor of ATP-sensitive potassium (KATP) channel, glibenclamide antagonizes the relaxation of the tracheal smooth muscle. This indicates that glibenclamide might attenuate airway inflammation while aggravate airway hyperresponsiveness (AHR) in asthmatics. Clinically, many diabetics with asthma are prescribed with glibenclamide to control blood glucose. However, whether glibenclamide could exert any effects on asthmatic inflammation remains unknown. Using an ovalbumin (OVA)-induced mouse model of asthma, we evaluated the effects of glibenclamide on the AHR and inflammation. Interestingly, glibenclamide reduced all the cardinal features of asthma in OVA-challenged mice, including AHR, airway inflammation, and T-helper type 2 (Th2) cytokines. Glibenclamide also downregulated OVA-induced expressions of vascular cell adhesion molecule 1 (VCAM-1) and phosphorylated signal transducer and activator of transcription 6 (p-STAT6) in the lung. In addition, increased sulfonylurea receptor 1 (SUR1) expression in the lung was observed after the OVA challenge. These findings suggest that the classic sulfonylurea glibenclamide plays an important protective role in the development of asthma, which not only provides the evidence for the safety of prescribed glibenclamide in diabetics combined with asthma but also indicates a possible new therapeutic for asthma via targeting glibenclamide-related pathways.

  19. Arachidonic acid metabolites do not mediate toluene diisocyanate-induced airway hyperresponsiveness in guinea pigs

    SciTech Connect

    Gordon, T.; Thompson, J.E.; Sheppard, D.

    1988-05-01

    Arachidonic acid metabolites have previously been demonstrated to mediate the airway hyperresponsiveness observed in guinea pigs and dogs after exposure to ozone. Guinea pigs were treated with indomethacin (a cyclooxygenase inhibitor), U-60,257 (piriprost, a 5-lipoxygenase inhibitor), or BW775c (a lipoxygenase and cyclooxygenase inhibitor) and exposed to air or 3 ppm TDI. Airway responsiveness to acetylcholine aerosol was examined 2 h after exposure. In control animals, the provocative concentration of acetylcholine which caused a 200% increase in pulmonary resistance over baseline (PC200) was significantly less (p less than 0.05) after exposure to TDI (8.6 +/- 2.0 mg/ml, geometric mean + geometric SE, n = 10) than after exposure to air (23.9 + 2.5 mg/ml, n = 14). The airway responsiveness to acetylcholine in animals treated with indomethacin or piriprost and exposed to TDI was not different from that of control animals exposed to TDI. Treatment with BW755c enhanced the airway hyperresponsiveness observed in animals exposed to TDI without altering the PC200 of animals exposed to air. The PC200 of animals treated with BW755c and exposed to TDI (2.3 + 0.8 mg/ml, n = 8) was significantly lower than the PC200 of control animals exposed to TDI (p less than 0.025). These results suggest that products of arachidonic acid metabolism are not responsible for TDI-induced airway hyperresponsiveness in guinea pigs. BW755c, however, appears to potentiate the TDI-induced airway hyperresponsiveness to acetylcholine by an as yet unidentified mechanism.

  20. Airway Epithelial Cell Integrity Protects from Cytotoxicity of Pseudomonas aeruginosa Quorum-Sensing Signals.

    PubMed

    Losa, Davide; Köhler, Thilo; Bacchetta, Marc; Saab, Joanna Bou; Frieden, Maud; van Delden, Christian; Chanson, Marc

    2015-08-01

    Cell-to-cell communication via gap junctions regulates airway epithelial cell homeostasis and maintains the epithelium host defense. Quorum-sensing molecules produced by Pseudomonas aeruginosa coordinate the expression of virulence factors by this respiratory pathogen. These bacterial signals may also incidentally modulate mammalian airway epithelial cell responses to the pathogen, a process called interkingdom signaling. We investigated the interactions between the P. aeruginosa N-3-oxo-dodecanoyl-L-homoserine lactone (C12) quorum-sensing molecule and human airway epithelial cell gap junctional intercellular communication (GJIC). C12 degradation and its effects on cells were monitored in various airway epithelial cell models grown under nonpolarized and polarized conditions. Its concentration was further monitored in daily tracheal aspirates of colonized intubated patients. C12 rapidly altered epithelial integrity and decreased GJIC in nonpolarized airway epithelial cells, whereas other quorum-sensing molecules had no effect. The effects of C12 were dependent on [Ca(2+)]i and could be prevented by inhibitors of Src tyrosine family and Rho-associated protein kinases. In contrast, polarized airway cells grown on Transwell filters were protected from C12 except when undergoing repair after wounding. In vivo during colonization of intubated patients, C12 did not accumulate, but it paralleled bacterial densities. In vitro C12 degradation, a reaction catalyzed by intracellular paraoxonase 2 (PON2), was impaired in nonpolarized cells, whereas PON2 expression was increased during epithelial polarization. The cytotoxicity of C12 on nonpolarized epithelial cells, combined with its impaired degradation allowing its accumulation, provides an additional pathogenic mechanism for P. aeruginosa infections.