Comparison of blood carbonic anhydrase activity of athletes performing interval and continuous running exercise at high altitude

The effects of high-intensity interval and continuous exercise on erythrocytes carbonic anhydrase (CA, EC 4.2.1.1) activity levels were scarcely investigated up until now. Here we present a study focused on the CA activity from erythrocytes of athletes experiencing interval and continuous training for 6 weeks, during cold weather and at high altitude (> 1600 m). We observed a 50% increase in the blood CA activity at the second week after initiation of the training in both interval and continuos running groups, whereas the control group did not experience any variation in the enzyme activity levels. In the trained individuals a mild decrease in their body mass, BMI and an increased (Formula presented.) were also observed. The CA activity returned at the basal values after 4–6 weeks after the training started, probably proving that a metabolic compensation occurred without the need of an enhanced enzyme activity. The unexpected 50% rise of activity for an enzyme which acts as a very efficient catalyst for CO2 hydration/bicarbonate dehydration, such as the blood CA, deserves further investigations for better understanding the physiologic basis of this phenomenon. © 2018, © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

Numerical analysis of an engineering structure effect on a heat loss of channel-free heat pipeline

The results of mathematical modeling of thermal modes of channel-free heating network laid in the areas of influence of engineering structures, as well as numerical analysis of the heat loss of the objects submitted. The regularities of heat transfer in the system and the factors that influence the intensification of heat losses are revealed. Revealed that thermal losses heating pipes laid in the channel-free zones of influence engineering structures decreases in the range from 1.53 to 10.79%, depending on the temperature inside the engineering structures and geometric characteristics of the system. It is shown that the standard method of calculation of heat loss channel-free heating pipes gives overestimated values of heat loss

Glutathione and its dependent enzymes' modulatory responses to toxic metals and metalloids in fish: a review

Toxic metals and metalloid are being rapidly added from multiple pathways to aquatic ecosystem and causing severe threats to inhabiting fauna including fish. Being common in all the type of aquatic ecosystems such as freshwater, marine and brackish water fish are the first to get prone to toxic metals and metalloids. In addition to a number of physiological/biochemical alterations, toxic metals and metalloids cause enhanced generation of varied reactive oxygen species (ROS) ultimately leading to a situ- ation called oxidative stress. However, as an important com- ponent of antioxidant defence system in fish, the tripeptide glutathione (GSH) directly or indirectly regulates the scav- enging of ROS and their reaction products. Additionally, several other GSH-associated enzymes such as GSH reduc- tase (GR, EC 1.6.4.2), GSH peroxidase (EC 1.11.1.9), and GSH sulfotransferase (glutathione-S-transferase (GST), EC 2.5.1.18) cumulatively protect fish against ROS and their reaction products accrued anomalies under toxic metals and metalloids stress conditions. The current review highlights recent research findings on the modulation of GSH, its redox couple (reduced glutathione/oxidised glutathione), and other GSH-related enzymes (GR, glutathione peroxidase, GST) involved in the detoxification of harmful ROS and their reaction products in toxic metals and metalloids-exposed fish