Fatty acids and sphingolipids profile in the blood plasma of experienced divers in response to hyperbaric exposure.

INTRODUCTION: Hyperbaric exposure mimics air-breathing scuba diving, which is reaching enormous popularity around the world. The diver's body is subjected to a broad range of divergent effects exerted by, e.g.: an increased partial pressure of inert gases, microclotting, oxidative stress and/or production of gas bubbles. However, very little is known regarding the impact of hyperbaric exposure on plasma fatty acids content and composition, together with the body's sphingolipids profile. MATERIAL AND METHODS: The aim of this study was to investigate the contents of major fatty acids present in the plasma as well as sphingolipids, namely: sphingosine (SPH); sphingosine-1-phosphate (S1P); sphinganine (SPA); and ceramide (CER), after hyperbaric exposure corresponding to dives conducted to the depths of 30 and 60 meters of seawater. For the plasma lipids measurements, high-performance liquid chromatography together with gas-liquid chromatography were applied. RESULTS: We demonstrated that hyperbaric exposure does not affect the content and composition of plasma fatty acids of experienced divers. Similarly, the amounts of major sphingolipids fractions were not influenced, as only the content of sphingosine-1-phosphate in the plasma was significantly decreased. CONCLUSIONS: Observed lack of significant changes in plasma lipid profile after hyperbaric exposure suggests that the procedure might be considered as secure. However, decreased sphingosine-1-phosphate content in the plasma might possibly exert some adverse effects.

High-frequency (13.56-MHz) and ultrahigh-frequency (915-MHz) radio identification systems do not affect platelet activation and functions.

BACKGROUND: In radiofrequency identification (RFID) systems used in labeling of blood components, blood cells are subjected to the direct influence of electromagnetic waves throughout the storage period. The aim of this study was to prove the safety of storage of platelet concentrates (PCs) in containers labeled with RFID tags. STUDY DESIGN AND METHODS: Ten pooled PCs obtained from 12 buffy coats each suspended in additive solution were divided into three separate containers that were assigned to three groups: control, PCs labeled with ultrahigh frequency (UHF) range tags and exposed to 915-MHz radio waves, and PCs labeled with high-frequency (HF) range tags and exposed to 13.56-MHz radio waves. PCs were stored at 20 to 24°C for 7 days. In vitro tests of platelet (PLT) function were performed on the first, fifth, and seventh days of storage. RESULTS: There were no significant differences in pH; hypotonic shock resistance; surface expression of CD62P, CD42a, or CD63; release of PLT-derived microparticles; PLT aggregation; and number of PLTs between PCs stored at a constant exposure to radio waves of two different frequencies and the control group on the first, fifth, and seventh days of storage. CONCLUSION: The results of the study indicate no impact of electromagnetic radiation generated in HF and UHF RFID systems and constant contact with the tags on the quality of stored PCs.

Metabolism, physiological role, and clinical implications of sphingolipids in gastrointestinal tract.

Sphingolipids in digestive system are responsible for numerous important physiological and pathological processes. In the membrane of gut epithelial cells, sphingolipids provide structural integrity, regulate absorption of some nutrients, and act as receptors for many microbial antigens and their toxins. Moreover, bioactive sphingolipids such as ceramide or sphingosine-1-phosphate regulate cellular growth, differentiation, and programmed cell death-apoptosis. Although it is well established that sphingolipids have clinical implications in gastrointestinal tumorigenesis or inflammation, further studies are needed to fully explore the role of sphingolipids in neoplastic and inflammatory diseases in gastrointestinal tract. Pharmacological agents which regulate metabolism of sphingolipids can be potentially used in the management of colorectal cancer or inflammatory bowel diseases. The aim of this work is to critically the review physiological and pathological roles of sphingolipids in the gastrointestinal tract.