Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA.
Published: April 2022
AI Article Synopsis
Article Abstract
Desiccation-tolerance of cells of four strains of and individual strains of , , , and were measured by two methods. The survival of water-acclimated cells both in filter paper and on the surface of stainless-steel coupons were measured. In filter paper at 40% relative humidity at 25 °C, survival of patient isolates of and cells was 28% and 34% after 21 days of incubation, whereas it was 100% for the Sorin 3T isolate of . On stainless-steel biofilms after 42 days of incubation at 40% relative humidity at 25 °C, survival of water-acclimated cells of was above 100%, while cells did not survive beyond 21 days, and survival of water-acclimated cells of and was 18% and 14%, respectively. On stainless-steel coupons, survival of patient and Sorin 3T isolates of was quite similar, specifically between 14% and 28% survival, after 42 days of incubation at 40% relative humidity at 25 °C. The experiments would support the hypothesis that some nontuberculous mycobacterial species are relatively desiccation-tolerant, whereas others are not. Further, long-term survival of the two strains is consistent with the presence of that species in Sorin 3T heater-coolers shipped throughout the world.
Coldwater species are challenged with increasing water temperatures and fluctuations over their upper thermal limits. This study evaluated the potential of acclimation to higher temperature and dietary antioxidants capacity to mitigate the adverse effects of heat shocks in rainbow trout. To this end, rainbow trout fingerlings were acclimated at optimal (14 °C) and high (20 °C) temperatures and fed on selenium (5 mg/kg) and polyphenol (2 g/kg) supplemented diets for 60 days and then were exposed to heat shocks by increasing water temperature up to 30 °C.
Desiccation-tolerance of cells of four strains of and individual strains of , , , and were measured by two methods. The survival of water-acclimated cells both in filter paper and on the surface of stainless-steel coupons were measured. In filter paper at 40% relative humidity at 25 °C, survival of patient isolates of and cells was 28% and 34% after 21 days of incubation, whereas it was 100% for the Sorin 3T isolate of .
Copper (Cu) is an abundant trace metal, and although essential at low levels, it is also potentially toxic to aquatic organisms. Mechanisms of toxicity and consequences of exposure vary depending on ionoregulatory status (acclimated to freshwater or salt water). The goal of this research was to examine the responses of hybrid striped bass (Morone chrysops x Morone saxatilis) exposed to Cu in freshwater and 15 g/L salt water.
(1) The marine teleost fish, Lagodon rhomboides, can only tolerate fresh water (5 mM Na) if Ca is also present (10 mM). Transfer to Ca-free fresh water is followed by a substantial increase in radioactive Na efflux with little or no change in the transepithelial potential. Addition of the chelating agent EDTA (2 mM) further increases Na efflux.
