Castro-Alférez M, Polo-López MI, Fernández-Ibáñez P. Intracellular mechanisms of solar water disinfection. Science Reports. 2016 Dec 2;6:38145. doi: 10.1038/srep38145.
Solar water disinfection (SODIS) is a zero-cost intervention measure to disinfect drinking water in areas of poor access to improved water sources, used by more than 6 million people in the world. The bactericidal action of solar radiation in water has been widely proven, nevertheless the causes for this remain still unclear. Scientific literature points out that generation of reactive oxygen species (ROS) inside microorganisms promoted by solar light absorption is the main reason. For the first time, this work reports on the experimental measurement of accumulated intracellular ROS in E. coli during solar irradiation. For this experimental achievement, a modified protocol based on the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA), widely used for oxidative stress in eukaryotic cells, has been tested and validated for E. coli. Our results demonstrate that ROS and their accumulated oxidative damages at intracellular level are key in solar water disinfection.
Posted in Disinfection
“The young Muslims, even the undecided ones, will understand that it’s not only a war against the Islamic State, which they try to paint as a homicidal monster, but one against Islam itself,” he added. “The Islamic State only uses measures permitted by Islam and Allah. It doesn’t kill people for the sake of killing, but only carries out the divine edicts against those who seek to corrupt our lands and life on earth, spread moral decay and oppose Sharia law.” click here
Posted in Politics
Implementation of a treaty that was crafted based on misinformation and deceit will not have a good outcome.
“Pope Francis urged national leaders on Monday to implement global environmental agreements without delay, a message that looked to be squarely aimed at U.S. President-elect Donald Trump.” click here
After reading articles like this I have to wonder. How does a democrat in insurgency benefit anyone?
“There are no consolation prizes from a loss as humbling and catastrophic as the heavily-favored Clinton suffered on Nov. 8. But for her aides, there is a measure of liberation, freedom from the constraints of having to defend their flawed, awkward front-runner and adopt the hell-to-pay role of insurgents.” click here
Coria P, Urízar C, Alba A, Noemí I, Pino A, Cerva JL. [The water supply of a pediatric hospital as a possible source of an outbreak of diarrhea due to Microsporidium spp. in immunocompromised patients] Rev Chilena Infectol. 2016 Aug;33(4):373-379. [Article in Spanish]
INTRODUCTION: The hospital water supply is a reservoir of a variety of potentially pathogenic microorganisms that can particularly affect children and immunocompromised patients. Potentially pathogenic Microsporidium spp. have been identified in water. Microsporidiosis is an emerging parasitic and opportunistic infection in immunocompromised patients.
OBJECTIVE AND METHOD: to describe an outbreak of nosocomial diarrhea due to Microsporidium, species Encephalitozoon intestinalis.
RESULTS: Seven cases of E. intestinalis associated diarrhea were reported between november 2012 and february 2013, in a unit of immunocompromised patients in L. Calvo Mackenna Children’s Hospital. Microsporidium spp. was found in the hospital water supply and water reservoir tank. Secondary cases were transmitted by contact. Control measures included contact precautions, not to use faucet water for hand washing, bottled water for drinking and water reservoir tank sanitation.
CONCLUSIONS: This research is about a nosocomial outbreak associated with water supply. Water quality in Chilean hospitals is an unresolved issue, especially in immunocompromised patient areas. Compliance of cleaning and disinfection of water supply systems in hospitals must be ensured.
Ground water transport models are relatively easy to develop if enough assumptions are made. Validation is needed before the output of any model is applied. Also, Pb-210 is a decay produce of radon and will be present in any water from an aquifer containing radium-226 or other radionuclides in its decay chain. This model must assume secular equilibrium.
Torres L, Yadav OP, Khan E. Holistic risk assessment of surface water contamination due to Pb-210 in oil produced water from the Bakken Shale. Chemosphere 2016 Nov 29;169:627-635. doi: 10.1016/j.chemosphere.2016.11.125.
A holistic risk assessment of surface water (SW) contamination due to lead-210 (Pb-210) in oil produced water (PW) from the Bakken Shale in North Dakota (ND) was conducted. Pb-210 is a relatively long-lived radionuclide and very mobile in water. Because of limited data on Pb-210, a simulation model was developed to determine its concentration based on its parent radium-226 and historical total dissolved solids levels in PW. Scenarios where PW spills could reach SW were analyzed by applying the four steps of the risk assessment process. These scenarios are: (1) storage tank overflow, (2) leakage in equipment, and (3) spills related to trucks used to transport PW. Furthermore, a survey was conducted in ND to quantify the risk perception of PW from different stakeholders. Findings from the study include a low probability of a PW spill reaching SW and simulated concentration of Pb-210 in drinking water higher than the recommended value established by the World Health Organization. Also, after including the results from the risk perception survey, the assessment indicates that the risk of contamination of the three scenarios evaluated is between medium-high to high.
Tyrrell JB, Hafida S, Stemmer P, Adhami A, Leff T. Lead (Pb) exposure promotes diabetes in obese rodents. J Trace Elem Med Biol. 2017 Jan;39:221-226. doi: 10.1016/j.jtemb.2016.10.007.
BACKGROUND: Pb (lead) exposure occurs at elevated frequency in urban inner city populations that also have high rates of obesity and diabetes.
OBJECTIVES: To determine if Pb can promote the development of diabetes in a setting of obesity, we examined the effect of Pb exposure on glucose metabolism in a rodent model of obesity.
METHODS: Adult female ZDF rats were exposed to Pb in drinking water for 24 weeks. Fasting blood glucose, insulin, and glucose tolerance were measured at regular intervals. Expression of hepatic gluconeogenic genes was measured in exposed and control animals and in cultured hepatoma cells treated with Pb.
RESULTS: Pb exposure induced fasting hyperglycemia after 8 weeks and glucose intolerance after 12 weeks of exposure. In addition, Pb-exposed animals showed elevated hepatic triglyceride levels and increased expression of the gluconeogenic genes PEPCK and glucose-6-phosphatase. In cultured rat hepatoma cells treatment with Pb stimulated PEPCK and glucose-6-phosphatase gene expression, suggesting a possible direct effect of Pb on hepatic gluconeogenic gene expression.
CONCLUSIONS: In the setting of obesity, Pb exposure is prodiabetic, causing fasting hyperglycemia and glucose intolerance in rats. A contributing factor to the metabolic effects of Pb may be the direct stimulation of hepatic gluconeogenic gene expression.