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Vasopressin and nitric oxide synthesis after three days of water or food deprivation Полный текст
2006
Mornagui, B. | Grissa, A. | Duvareille, M. | Gharib, C. | Kamoun, A. | El-Fazaa, S. | Gharbi, N.
Nitric oxide has been suggested to be involved in the regulation of fluid and nutrient homeostasis. In the present investigation, vasopressin and nitric oxide metabolite (nitrite and nitrate) levels were determined in plasma of male Wistar rats submitted to water or food deprivation for three days. Hematocrit and plasma sodium showed marked increase in dehydrated and starved rats. Potassium levels and plasma volume decreased in both treated groups. Plasma osmolality and vasopressin levels were significantly elevated in water deprived (362.8±7.1 mOsm/kg H<sub>2</sub>O, 17.3±2.7 pg/ml, respectively, p<0.001) rats, but not in food deprived (339.9±5.0, 1.34±0.28) rats, compared to the controls (326.1±4.1, 1.47±0.32). The alterations observed in plasma vasopressin levels were related to plasma osmolality rather than plasma volume. Plasma levels of nitrite and nitrate were markedly increased in both water and food deprived rats (respectively, 2.19±0.29 mg/l and 2.22±0.17 mg/l <i>versus</i>1.33±0.19 mg/l, both p<0.01). There was a significant negative correlation between plasma nitrite and nitrate concentration and plasma volume. These results suggest that both dehydration and starvation increase plasma nitric oxide, probably by activation of nitric oxide synthases. The release of nitric oxide may participate in the regulation of the alteration in blood flow, fluid and nutrient metabolism caused by water deprivation or starvation.
Показать больше [+] Меньше [-]Integrated spatial assessment of the water, energy and food dimensions of the Sustainable Development Goals Полный текст
2017
Giupponi, Carlo | Gain, Animesh Kumar
Water is considered the bloodstream of the biosphere, but its management is one of the most important challenges for human development. In view of the sustainable water management, several approaches have been proposed: Integrated Water Resources Management, Adaptive Management and, more recently, Water–Energy–Food (WEF) Nexus. Considering these approaches, over the last few decades, extensive efforts have been made to develop assessment methods and tools framed within the paradigm of sustainable development. As part of a holistic assessment of water resources, the recent approach based upon the WEF Nexus narrows down the consideration of intersectoral linkages to three dimensions that are of prominent interest, in particular in developing countries. This study presents a comprehensive indicator-based approach for the assessment of water, energy and food securities, with reference to the Sustainable Development Goals of the United Nations. The main ambition of the proposed approach is to provide a tool to monitor progresses, compare different geographical areas, highlight synergies and conflicts amongst and within the three dimensions of the WEF Nexus, and provide support for improved—more effective—management strategies to meet the goals. The proposed approach is demonstrated in the Ganges–Brahmaputra–Meghna (GBM) River Basin in Asia and to the Po River Basin in Europe. The comparative analysis suggests that WEF security is currently rather low in the GBM basin compared to the other case study and other parts of the world and allows the identification of which dimensions (indicators) require special attention on the part of local and global policy makers.
Показать больше [+] Меньше [-]Reversible and Selective Turn-on Fluorescent and Naked-Eye Colorimetric Sensor to Detect Cyanide in Tap Water, Food Samples, and Living Systems Полный текст
2020
Bai, Cui-Bing | Zhang, Jie | Qiao, Rui | Zhang, Qiu-Yan | Mei, Meng-Yun | Chen, Meng-Yu | Wei, Biao | Wang, Chang | Qu, Chang-Qing
The identification of CN– in water, seeds, and biological systems has, because of its high toxicity, attracted the increasing attention of many chemical industry researchers. In the work, a novel highly selective and reversible sensor, MMY, was shown to recognize CN– effectively. The color and fluorescent changes verified the interaction of MMY with CN–, and the fluorescence lifetime of MMY was also changed upon addition of CN–. A mode of interaction of MMY with CN– based on the results of various experiments was speculated. The LOD of MMY toward CN– was 9.4 × 10–¹⁰ M, lower than the concentration of CN– deemed acceptable by the WHO (World Health Organization) and the U.S. EPA (United States Environmental Protection Agency). MMY showed good reversibility and reusability for detecting CN–. In addition, test slips and silica plates were both earned by ourselves, which were able to recognize CN– qualitatively. Additionally, MMY could recognize CN– in tap water quantitatively with the use of a smartphone APP. Interestingly, MMY was also used to detect CN– in seeds. It was valid to image CN– in Caenorhabditis elegans and mice with a vivid “turn-on” fluorescence. MMY thus can circulate in the bloodstream.
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