High-throughput bioaffinity mass spectrometry for screening and identification of designer anabolic steroids in dietary supplements.

A generic high-throughput bioaffinity liquid chromatography-mass spectrometry (BioMS) approach was developed and applied for the screening and identification of known and unknown recombinant human sex hormone-binding globulin (rhSHBG)-binding designer steroids in dietary supplements. For screening, a semi-automated competitive inhibition binding assay was combined with fast ultrahigh-performance-LC-electrospray ionization-triple-quadrupole-MS (UPLC-QqQ-MS). 17ß-Testosterone-D3 was used as the stable isotope label of which the binding to rhSHBG-coated paramagnetic microbeads was inhibited by any other binding (designer) steroid. The assay was performed in a 96-well plate and combined with the fast LC-MS, 96 measurements could be performed within 4 h. The concentration-dependent inhibition of the label by steroids in buffer and dietary supplements was demonstrated. Following an adjusted bioaffinity isolation procedure, suspect extracts were injected into a chip-UPLC(NanoTile)-Q-time-of-flight-MS system for full-scan accurate mass identification. Next to known steroids, 1-testosterone was identified in three of the supplements studied and the designer steroid tetrahydrogestrinone was identified in a spiked supplement. The generic steroid-binding assay can be used for high-throughput screening of androgens, estrogens, and gestagens in dietary supplements to fight doping. When combined with chip-UPLC-MS, it is a powerful tool for early warning of unknown emerging rhSHBG bioactive designer steroids in dietary supplements.

[Investigation of keratinophilic fungi in Laodicea's recreation workshop]. / Laodikeia rekreasyon atölyesinde keratinofilik mantarlarin arastirilmasi.

Recreation ateliers in which archeological remnants are operated to be restorated to their original forms, are closed places with high humidity rates. The hands and the nails of archeology workers contact directly with the keratinophilic fungi during recreation facilities. The aim of this study was to investigate the presence and distribution of keratinophilic fungi in Laodikeia antique city's recreation atelier (Pamukkale region; Aegean part of Turkey). A total of 18 archeological remnant samples were collected from Laodikeia recreation atelier during the digging period of 2006. The samples were screened for the prevalence of keratinophilic fungi by hair baiting technique and the isolates were identified by conventional mycological methods. Of the samples 38.9% (7/18) were found positive and the distribution of keratinophilic fungi were as follows; Chrysosporium spp. (22.2%) (two of them were C. keratinophilum), Aphanoascus spp. (11.1%), Auxarthron spp. (5.5%) and Trichophyton rubrum (5.5%). It was concluded that the patient histories including living and working conditions, may be helpful to identify the keratinophilic fungi growing on cycloheximide containing mycologic media and archeology workers should be informed for the diseases caused by environmental keratinophilic fungi.

[Investigation of serum resistance for Pseudomonas aeruginosa and Acinetobacter baumannii strains]. / Pseudomonas aeruginosa ve Acinetobacter baumannii suslarinda serum direncinin arastirilmasi.

Serum resistance is one of the major virulence factors of Gram negative bacteria. The aim of this study was to investigate the serum resistance of Pseudomonas aeruginosa and Acinetobacter baumannii strains isolated from various clinical samples (19 tracheal aspirates, 14 urine, 7 sputum, 7 wound and one peritoneal fluid specimens). Forty-eight P. aeuginosa and 48 A. baumannii strains were tested for human serum bactericidal effect by using Benge's method. Thirty-five (72.9%), 9 (18.7%), and 4 (8.3%) of P. aeruginosa strains were found to be resistant, intermediate sensitive and sensitive to serum, respectively. These rates were detected as 81.2% (39/48), 14.5% (7/48), and 4.1% (2/48) for A. baumannii strains, respectively. It can be concluded that, high serum resistance rates of P. aeruginosa and A. baumannii isolates might have an important role in the pathogenesis of infections of these bacteria.