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a b s t r a c tThe widespread occurrence of antibiotics as contaminants in the aquatic environment has increased attention in the last years. The concern over the release of antibiotics into the environment is related primarily to the potential for the development of antimicrobial resistance among microorganisms. This article presents an overview of analytical methodologies for the determination of quinolone (Qs) and fluoroquinolone (FQs), macrolide (MLs), tetracycline (TCs), sulfonamide (SAs) antibiotics and trimethoprim (TMP) in different environmental waters. The analysis of these antibiotics has usually been carried out by high-performance liquid chromatography (HPLC) coupled to mass spectrometry (MS) or tandem mass spectrometry (MS/MS) and to a lesser extent by ultraviolet (UV) or fluorescence detection (FD). A very important step before LC analysis is sample preparation and extraction leading to elimination of interferences and prevention of matrix effect and preconcentration of target analytes.

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Mucosal-associated invariant T (MAIT) cells are innate-like T cells comprising up to 10% of the peripheral blood T cells in humans. During ontogeny, MAIT cells can first be detected in the cord blood in low amounts, but rise steadily after birth. In this population-based study, we show that their counts continue to increase, reaching maximal levels (4.5% of CD3 + cells, 65 cells/ll) in the third and fourth decenniums. At this age, the amounts of MAIT cells exhibit the highest interindividual variability. The values then dramatically decline; subjects 80 years old and older have on average 10 times less MAIT cells, both absolutely and as a percentage among CD3 + T cells, than subjects in fertile age. The senescence of MAIT cells is associated with decreased CD8/double negative (DN) ratio. Finally, we observed significantly higher amounts of MAIT cells in women of reproductive age than in men of the same age. Our data suggest that further studies aimed at elucidating a role of MAIT cells in human pathologies must recruit age-and gender-matched controls.

Vitamin C (L-ascorbic acid) has been known as an antioxidant for most people. However, its physiological role is much larger and encompasses very different processes ranging from facilitation of iron absorption through involvement in hormones and carnitine synthesis for important roles in epigenetic processes. Contrarily, high doses act as a pro-oxidant than an anti-oxidant. This may also be the reason why plasma levels are meticulously regulated on the level of absorption and excretion in the kidney. Interestingly, most cells contain vitamin C in millimolar concentrations, which is much higher than its plasma concentrations, and compared to other vitamins. The role of vitamin C is well demonstrated by miscellaneous symptoms of its absence—scurvy. The only clinically well-documented indication for vitamin C is scurvy. The effects of vitamin C administration on cancer, cardiovascular diseases, and infections are rather minor or even debatable in the general population. Vitamin C is relatively safe, but caution should be given to the administration of high doses, which can cause overt side effects in some susceptible patients (e.g., oxalate renal stones). Lastly, analytical methods for its determination with advantages and pitfalls are also discussed in this review.