The described SCAC protocol is practicable and gives additional information not yet acquired by radiologic typing and seems suitable for studies evaluating genetic influence and biomarkers.

The appearance of pyrazolam in Internet shops selling 'research chemicals' in 2012 marked the beginning of designer benzodiazepines being sold as recreational drugs or 'self medication'. With recent changes in national narcotics laws in many countries, where two uncontrolled benzodiazepines (phenazepam and etizolam), which were marketed by pharmaceutical companies in some countries, were scheduled, clandestine laboratories seem to turn to poorly characterized research drug candidates as legal substitutes. Following the appearance of pyrazolam, it comes with no surprise that recently, flubromazepam (7-bromo-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one), a second designer benzodiazepine, was offered on the market. In this article, this new compound was characterized using nuclear magnetic resonance, gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS/MS) and liquid chromatography quadrupole time-of-flight MS (LC-Q-ToF-MS). Additionally, a study was carried out, in which one of the authors consumed 4 mg of flubromazepam to gain preliminary data on the pharmacokinetic properties and the metabolism of this compound. For this purpose, serum as well as urine samples were collected for up to 31 days post-ingestion and analyzed applying LC-MS/MS and LC-Q-ToF-MS techniques. On the basis of this study, flubromazepam appears to have an extremely long elimination half-life of more than 100 h. One monohydroxylated compound and the debrominated compound could be identified as the predominant metabolites, the first allowing a detection of a consumption for up to 28 days post-ingestion when analyzing urine samples in our case. Additionally, various immunochemical assays were evaluated, showing that the cross-reactivity of the used assay seems not to be sufficient for safe detection of the applied dose in urine samples, bearing the risk that it could be misused in drug-withdrawal settings or in other circumstances requiring regular drug testing. Furthermore, it may be used in drug-facilitated crimes without being detected.

BackgroundTherapeutic drug monitoring of immunosuppressive drugs in organ-transplanted patients is crucial to prevent intoxication or transplant rejection due to inadequate dosage. The commonly used immunoassays have been gradually undergoing replacement by mass spectrometry, since this physical method offers both a higher sensitivity and specificity. However, a switch should be carefully considered because it is a challenging procedure and needs to be thoroughly validated.From an economic perspective it is reasonable to include mycophenolic acid into the assay, because this saves the necessity for an additional measurement. However, to date very few validation protocols for the measurement of immunosuppressants, including mycophenolic acid, are available. In order to adequately compensate for matrix effects, the use of stable isotope labeled internal standards is advisable. Here, the authors describe a single method suitable for the quantification of cyclosporine A, tacrolimus, sirolimus, everolimus and mycophenolic acid, based on deuterated internal standards.MethodsPlasma proteins were precipitated with zinc-sulfate, followed by an online solid phase extraction in the flow-through direction. Chromatographic separation was performed by a c18-phenyl-hexyl column. For subsequent mass spectrometric analysis stable-isotope-labeled internal standards were used. Results were available after 3.5 minutes.ResultsLow quantification limits (accuracy: 104 - 118%) and linearity resulted in 2 -1250 ng/ml for cyclosporine A; 0.5 - 42.2 ng/ml for tacrolimus; 0.6 - 49.2 ng/ml for sirolimus; 0.5 - 40.8 ng/ml for everolimus and 0.01 - 7.5 μg/ml for mycophenolic acid. Intra-assay precision revealed a coefficient of variation (CV) of 0.9 - 14.7%, with an accuracy of 89 - 138%. The CV of inter-assay precision was 2.5 - 12.5%, with an accuracy of 90 - 113%. Recovery ranged from 76.6 to 84%. Matrix effects were well compensated by deuterated internal standards.ConclusionsThe authors present a fast, economical and robust method for routine therapeutic drug monitoring comprising five immunosuppressants including mycophenolic acid.

No abstract

Purpose This study compares vitreal levels of erythropoietin (EPO) in patients with retinal vein occlusion (RVO) with control subjects. In addition, it investigates different RVO disease parameters (time of vein occlusion, patient age, vitreal vascular endothelial growth factor (VEGF) levels, and extent of central macular edema) for possible correlations with vitreal EPO levels. Methods Serum and vitreal EPO were measured from 6 patients with branch retinal vein occlusion, 6 patients with central retinal vein occlusion, and 12 control subjects (10 macular puckers and 2 macular holes). Results Serum EPO levels (9.8 ± 4.9 mU/mL) did not differ between the RVO and control groups and were significantly lower than vitreal EPO levels in all groups. Vitreal EPO was elevated both in branch RVO (91 ± 59 mU/mL) and central RVO (182 ± 70 mU/mL) compared with controls (35 ± 24 mU/mL). Increased vitreal EPO correlated with higher vitreal VEGF (r = 0.64, P = 0.0008) and more pronounced central macular edema (r = 0.66, P = 0.001). Conclusion The results from this study indicate that EPO is locally expressed in the retina and that it is upregulated together with VEGF in RVO eyes. Because of its role both in neuroprotection and angiogenesis, ocular EPO might represent an interesting target to investigate in patients with RVO, especially in light of the current anti-VEGF treatments.