49 research outputs found
ETHANOL-INDUCED ALTERATIONS IN CARDIAC ENZYMES–AMELIORATIVE EFFECT OF THESPESIA POPULNEA LEAF EXTRACT
Objective: This study covers the estimation of changes in cardiac enzymes such as ATPases and antioxidant enzymes following ethanol-administration in rats, and the possible ameliorative effect of leaf extract of the plant Thespesia populnea (TP) on these changes.Methods: Male adult Wistar rats were divided into 10 groups of six rats each. Vehicle controls received 5% gum acacia. Experimental groups received ethanol (20%, 2g/kg); or TP leaf extract (200 mg/kg and 400 mg/kg respectively); or vitamin E (25 mg/kg); or carvedilol (1 mg/kg) per orally every morning for 6 w, individually as well as in combination with ethanol. Following this, changes in the activities of Na+ ATPase, Ca2+ATPase, Mg2+ATPase, and antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were determined in the heart tissue and compared with those in vehicle control.Results: Ethanol (20%, 2g/kg) treatment caused a reduction from the vehicle control in activities of all the examined enzymes, with minimal reduction in Mg2+ ATPase activity (29.26%) and maximal reduction in CAT activity (71.05%). With TP leaf extracts of 200 and 400 mg/kg, vitamin E and carvedilol individually, the vehicle controls showed percent changes in enzyme activities ranging from ‒8.24% for Mg2+ ATPase activity to+109.39% for Na+ ATPase activity caused by carvedilol. When administered along with ethanol, TP leaf extracts, vitamin E and carvedilol reversed the effect of ethanol to various degrees and brought back the enzyme activities to near vehicle control levels. While recovery with 200 mg Thespesia leaf extract was less, ranging from 24.1% for Mg2+ATPase activity to 190.91% for CAT activity, 400 mg Thespesia extract effected a greater recovery, with a minimum of 48.19% for Mg2+ ATPase activity and a maximum of 222.73% for CAT activity, as compared with ethanol-treated rats as controls. These effects could be interpreted in terms of the adverse effects of ethanol on cardiac function and the ameliorative effects, primarily the antioxidant potential, of TP leaf extracts, vitamin E and carvedilol.Conclusion: The restoration of enzyme activities with TP leaf extract may promote recovery of cardiac tissue from oxidative damage. Results from the current study indicate that treatment with TP leaf extract reduces ethanol-induced oxidative stress in rat heart and hence may help prevent cardiac damage.Â
Implementing opportunistic spectrum access in LTE-Advanced
Long term evolution advanced (LTE-A) has emerged as a promising mobile broadband access technology aiming to cope with the increasing traffic demand in wireless networks. However, the enhanced spectral efficiency offered by LTE-A may become futile without a better management of scarce and overcrowded electromagnetic spectrum. In this sense, cognitive radio (CR) has been proposed as a potential solution to the problem of spectrum scarcity. Among all the mechanisms provided by CR, opportunistic spectrum access (OSA) aims at a dynamic and seamless use of certain licensed bands provided the licensee is not harmfully affected. This operation requires spectral awareness in order to avoid interferences with licensed systems. In spite of implementing some spectrum sensing mechanisms, LTE-A technology lacks other tools that are needed in order to improve the knowledge of the radio environment. This work studies the adoption of a Geo-located data base (Geo-DB) that cooperatively retrieves and maintains information regarding the location of unutilized portions of spectrum potentially available for OSA. Moreover, the potential benefit of this LTE-compliant OSA solution is evaluated using a calibrated simulation tool, by which numerical results allow us to optimally configure the system and show that the proposed opportunistic system is able to significantly improve its performance.The authors would like to thank the funding received from the Ministerio de Ciencia e Innovacion within the Project number TEC2011-27723-C02-02 and from the Ministerio de Industria, Turismo y Comercio TSI-020100-2011-266 funds. This article had been written in the framework of the CELTIC project CP08-001 COMMUNE. Study by X. Gelabert is funded by the BP-DGR 2010 scholarship (ref. 00192). 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Assessment of Insulin Injection Practice of Nurses Working in a Tertiary Healthcare Center of Nepal.
Introduction: Sound knowledge and good practice on insulin injection technique are essential for nurses in order to administer insulin correctly and to educate patients or their relatives adequately. This study aimed to assess the insulin injection practice through the use of insulin pen among nurses working in a tertiary healthcare center of Nepal. Materials and Methods: A cross-sectional descriptive study was conducted among 67 nurses working in one of the tertiary healthcare centers of Nepal. Demographic information and insulin injection practice of nurses through the use of insulin pen were assessed using self-administered questionnaire. Each correct practice was scored "1" and incorrect practice was scored "0." Results. The median (IQR) insulin injection practice score of nurses was 11 (9-12) out of 16. Thirty-seven (55.2%) nurses store insulin pen filled with insulin cartridge at room temperature while 57 (85.1%) nurses store unopened cartridge at refrigerator (2-8°C). The practice of hand washing and injection site cleaning was mentioned by 92.5% and 82.1% of the nurses, respectively. However, just over half of the nurses mix the premix (cloudy) insulin and prime insulin pen before each injection. Thirty-four (50.7%) nurses do not lift skin during injection and more than half of the nurses keep needle beneath the skin for less than 5 seconds after completely injecting the required dose of insulin. One out of ten nurses massage injection site after injecting insulin. Most of the nurses (86.6%) use single needle more than once and the median (IQR) frequency of needle reuse was 6 (3-12). Similarly, systematic site rotation was performed by 59 (88.1%) nurses and twenty (29.9%) nurses claim that they use single insulin pen for two different cartridges. Conclusion: The insulin injection practice of nurses assessed through the use of insulin pen was suboptimal and highlights the need for urgent educational intervention