30 research outputs found

    Circulating irisin levels in newly diagnosed obstructive sleep apnea patients

    Get PDF
    Introduction: Obstructive sleep apnea syndrome (OSAS) is commonly associated with obesity, insulin resistance, metabolic syndrome, hypertension, and coronary artery disease. Irisin is a newly identified myokine and its serum concentration was found to be correlated with cardiac troponin and creatin kinase-MB in acute myocardial infarction patients. Furthermore, irisin levels were positively associated with endothelium-dependent vasodilation in type 2 diabetic patients.Aim: In this study, we aimed to investigate serum irisin level in the newly diagnosed OSAS patients.Materials and Methods: After obtaining ethical approval, 32 OSAS patients were included. All patients gave written informed consent. Diagnosis of OSAS was verified by an overnight polysomnography (PSG) and made by an apnea hypopnea index equal to or higher than 5. Venous blood samples were collected in the morning between 08.00 – 10.00 after PSG (n=25) or after one-night CPAP treatment (n=7). Serum irisin concentrations were studied by ELISA.Results and Conclusion: Serum irisin concentrations were significantly higher in newly diagnosed OSAS group than in OSAS group after one night of CPAP treatment (199.7±42.4 vs 159.7±18.3 ng/mL respectively; p<0.01). These results suggest that increased serum irisin levels can be reduced by CPAP treatment and elevated serum irisin levels may be due to increased respiratory muscle activity and body temperature.

    Enhancing electrochromic and kinetic properties of poly(2,3-bis(4-tert-butylphenyl)-5,8-di(1H-pyrrol-2-yl) quinoxaline) by copolymerization

    No full text
    Electrochemical copolymerization was utilized to combine several properties into a single material in order to obtain a highly stable polymer with a low band gap to meet the requirements for color variation. In that sense, two new donor acceptor type electrochromic copolymers of 2,3-bis(4-tert-butylphenyl)5,8-di(1H-pyrrol-2-yl) quinoxaline (TBPPQ) with bis(3,4-ethylenedioxythiophene) (BiEDOT) and with 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-dodecyl-2H-benzo [ 1,231 triazole (BEBT) were synthesized by electrochemical polymerization. Polymers revealed multicolor electrochromic properties with distinct accessible states and low operation potentials. Electrochromic and kinetic properties of polymers were investigated using cyclic voltammetry (CV) and in situ UV-vis-NIR spectroscopy

    Neutral-State Green Conjugated Polymers from Pyrrole Bis-Substituted Benzothiadiazole and Benzoselenadiazole for Electrochromic Devices

    No full text
    Two donor/acceptor/donor-type pyrrole-incorporated monomers, 4,7-di(1H-pyrrol-2-yl)benzo[c][1,2,5]thiadiazole (M1) and 4,7-di(1H-pyrrol-2-yl) benzo[c][1,2,5] selenadiazole (M2), were synthesized and polymerized electrochemically. The resulting polymers (P1 and P2) were investigated in terms of their electrochromic and optical properties. Spectroelectrochemistry studies revealed that both polymers show two distinct absorptions in both red and blue regions. The absorptions at around 400 and 700 nm correspond to neutral-state green polymers P1 and P2, which is a unique property for conjugated polymers. Optical band gaps were calculated as 1.12 and 1.08 eV for P1 and P2, respectively

    Immobilization of Invertase in Copolymer of 2,5-Di(thiophen-2-yl)-1-p-Tolyl-1H-Pyrrole with Pyrrole

    No full text
    Immobilization of invertase in conducting copolymer matrix of 2,5-di(thiophen-2-yl)-1-p-tolyl-1H-pyrrole with pyrrole (poly(DDTP-co-Py)) was achieved via electrochemical polymerization. Kinetic parameters, Michaelis-Menten constant, Km and the maximum reaction rate, Vmax were investigated. Operational stability and temperature optimization of the enzyme electrodes were also examined. Immobilized invertase reveals maximum activity at 50 degrees C and; pH 8 and pH 4 for two copolymer matrices. Although the same two monomers are utilized for the copolymer synthesis, the way the copolymer is produced results in quite different responses in terms of enzyme activity, optimum pH and kinetic parameters. Excellent operational stability of the enzyme electrodes enables their repetitive use in the determination of invert sugar

    Donor acceptor type neutral state green polymer bearing pyrrole as the donor unit

    No full text
    A new neutral state green polymer, poly (2,3-bis(4-tert-butylphenyl)-5,8-di(1H-pyrrol-2-yl) quinoxaline) (PTBPPQ) was synthesized and its potential use as an electrochromic material was investigated. Spectroelectrochemistry studies showed that polymer reveals two distinct absorption bands as expected for a donor-acceptor type polymer, at 408 and 745 nm. In addition, polymer has excellent switching properties with satisfactory optical contrasts and very short switching times. Outstanding optical contrast in the NIR region and stability make this polymer a great candidate for many applications. It should be noted that PTBPPQ is one of the few examples of neutral state green polymeric materials with superior switching properties. Hence, PTBPPQ can be used as a green polymeric material for display technologies

    Effects of chronic exposure to electromagnetic waves on the auditory system

    No full text
    WOS: 000356673400004PubMed: 25836770Conclusion: the results support that chronic electromagnetic field exposure may cause damage by leading to neuronal degeneration of the auditory system. Objectives: Numerous researches have been done about the risks of exposure to the electromagnetic fields that occur during the use of these devices, especially the effects on hearing. the aim of this study is to evaluate the effects of the electromagnetic waves emitted by the mobile phones through the electrophysiological and histological methods. Methods: Twelve adult Wistar albino rats were included in the study. the rats were divided into two groups of six rats. the study group was exposed to the electromagnetic waves over a period of 30 days. the control group was not given any exposure to the electromagnetic fields. After the completion of the electromagnetic wave application, the auditory brainstem responses of both groups were recorded under anesthesia. the degeneration of cochlear nuclei was graded by two different histologists, both of whom were blinded to group information. Results: the histopathologic and immunohistochemical analysis showed neuronal degeneration signs, such as increased vacuolization in the cochlear nucleus, pyknotic cell appearance, and edema in the group exposed to the electromagnetic fields compared to the control group. the average latency of wave in the ABR was similar in both groups (p > 0.05)
    corecore