PRPS1 loss-of-function variants, from isolated hearing loss to severe congenital encephalopathy: New cases and literature review.

We describe two sporadic and two familial cases with loss-of-function variants in PRPS1, which is located on the X chromosome and encodes phosphoribosyl pyrophosphate synthetase 1 (PRS-1). We illustrate the clinical variability associated with decreased PRS-1 activity, ranging from mild isolated hearing loss to severe encephalopathy. One of the variants we identified has already been reported with a phenotype similar to our patient's, whereas the other three were unknown. The clinical and biochemical information we provide will hopefully contribute to gain insight into the correlation between genotype and phenotype of this rare condition, both in females and in males. Moreover, our observation of a new family in which hemizygous males display hearing loss without any neurological or ophthalmological symptoms prompts us to suggest analysing PRPS1 in cases of isolated hearing loss. Eventually, PRPS1 variants should be considered as a differential diagnosis of mitochondrial disorders.

Efficacy of a CO2-releasing suppository in dyschezia: a double-blind, randomized, placebo-controlled clinical trial.

BACKGROUND: Constipation has a significant impact on quality of life. Aim of this study was to evaluate the safety and the efficacy for relieving dyschezia symptoms of a CO2-releasing suppository in a randomized, placebo-controlled, clinical trial. METHODS: Fifty-three office-based primary care physicians and 24 gastroenterologists conducted the study in France, between November 2010 and January 2012. Patients (aged 18-75 years) with dyschezia were eligible. Patients were randomly allocated a once-a-day suppository (CO2-releasing suppository or placebo) for 21 days. Primary endpoint was the change, from Day 0 to Day 21, in the intensity of discomfort related to dyschezia based on a self-assessed 0-100 visual analogue scale. RESULTS: A total of 323 patients were randomized, i.e. 166 into the intervention group and 157 into the placebo group. Co-variance analysis showed a greater reduction in discomfort visual analogue scale score in the intervention group (-34.5mm; standard error of the mean: 1.8mm) than in the placebo group (-26.2mm; standard error of the mean: 1.9 mm; p<0.001). The greater efficacy of the CO2-releasing suppository was confirmed for all secondary efficacy parameters. No significant side effects for either treatment were observed. CONCLUSION: A CO2-releasing suppository is more effective than a placebo for the relief of symptoms of dyschezia. This efficacy is associated with a good safety profile.

The contribution of Raman spectroscopy to the analytical quality control of cytotoxic drugs in a hospital environment: eliminating the exposure risks for staff members and their work environment.

The purpose of the study was to perform a comparative analysis of the technical performance, respective costs and environmental effect of two invasive analytical methods (HPLC and UV/visible-FTIR) as compared to a new non-invasive analytical technique (Raman spectroscopy). Three pharmacotherapeutic models were used to compare the analytical performances of the three analytical techniques. Statistical inter-method correlation analysis was performed using non-parametric correlation rank tests. The study's economic component combined calculations relative to the depreciation of the equipment and the estimated cost of an AQC unit of work. In any case, analytical validation parameters of the three techniques were satisfactory, and strong correlations between the two spectroscopic techniques vs. HPLC were found. In addition, Raman spectroscopy was found to be superior as compared to the other techniques for numerous key criteria including a complete safety for operators and their occupational environment, a non-invasive procedure, no need for consumables, and a low operating cost. Finally, Raman spectroscopy appears superior for technical, economic and environmental objectives, as compared with the other invasive analytical methods.

Comparison of Raman spectroscopy vs. high performance liquid chromatography for quality control of complex therapeutic objects: model of elastomeric portable pumps filled with a fluorouracil solution.

This study compares the performance of a reference method of HPLC to Raman spectroscopy (RS) for the analytical quality control (AQC) of complex therapeutic objects. We assessed a model consisting of a widely used anticancer drug, i.e., 5-fluorouracil, which was compounded in a complex medical device, i.e., an elastomeric portable infusion pump. In view of the main objective, the two methods provided excellent results for the analytical validation key criteria, i.e., trueness, precision and accuracy, ranging from 7.5 to 50mg/mL and in either isotonic sodium or 5% dextrose. The Spearman and Kendall correlation tests (p-value<1×10(-15)) and the statistical studies performed on the graphs confirm a strong correlation in the results between RS and the standard HPLC under the experimental conditions. The selection of a spectral interval between 700 and 1400cm(-1) for both the characterization and quantification by RS was the result of a gradual process optimization, combining matrix and packaging responses. In this new application, we demonstrate at least eight benefits of RS: (a) operator safety, (b) elimination of disposables, (c) elimination of analysis waste, which contributes to the protection of the environment, (d) a fast analytical response of less than 2min, (e) the ability to identify the solubilizing phase, (f) reduction of the risk of errors because no intrusion or dilution are needed, (g) negligible maintenance costs and (h) a reduction in the budget dedicated to technician training. Overall, we indicate the potential of non-intrusive AQC performed by RS, especially when the analysis is not possible using the usual techniques, and the technique's high potential as a contributor to the safety of medication.

Liquid chromatography-tandem mass spectrometry assay for therapeutic drug monitoring of the tyrosine kinase inhibitor, midostaurin, in plasma from patients with advanced systemic mastocytosis.

We developed and validated quantitative bioanalytical liquid chromatography-tandem mass spectrometry assay for the protein kinase inhibitor, midostaurin. Plasma samples were pre-treated using a protein precipitation with methanol containing midostaurin-d5 as an internal standard. After centrifugation, 5µL of the supernatant was injected into the chromatographic system. The system consisted of a 3.5µm particle bonded octadecyl silica column, with gradient elution using a mixture of 0.1% (v/v) formic acid in acetonitrile and 10mM ammonium formate in water with 0.1% formic acid. The analyte was quantified using the selected reaction-monitoring mode of a triple quadrupole mass spectrometer equipped with a heated electrospray interface. The assay was validated in a 75-2500ng/mL calibration range. For quality control, within-day and between-day precisions were 1.2-2.8%, and 1.2-6.9%, respectively. The ß-expectation tolerance limit (accuracy) met the limits of acceptance ±15% (±20% for the LLQ). The drug was sufficiently stable under all relevant analytical conditions. The assay has successfully been used to assess drug levels for therapeutic drug monitoring in patients presenting advanced systemic mastocytosis and treated with the promising midostaurin.

[A medical-pharmaceutical partnership model as a contributor to the success in conditioning regimen for allogenic hematopoietic stem cell transplantation in adults: a cross-reflection on our organizations]. / Modèle de coopération médico-pharmaceutique comme contributeur au succès du conditionnement de la greffe allogénique de cellules souches hématopoïétiques chez l'adulte : un regard croisé sur nos organisations.

Allogeneic hematopoietic stem-cell transplant (allo-SCT) remains the only cure for many hematological malignancies and some benign and congenital diseases. Busulfan, proposed in its injectable form, has quickly become a mainstay of pharmacological and myeloablative (or non-myeloablative) conditioning. This is following the outbreak in 2010 of a multicenter international clinical phase II trial, we tested the robustness and reliability of our organization in a complex model of organization and multifactorial partnership. In this type "BuCy2" protocol based on a classical treatment duration of 4 consecutive days, the administration of IV busulfan is given in one single daily infusion instead of the conventional 16 infusions, while keeping the same total dose. Under these conditions, the treatment is totally secured using a therapeutic drug monitoring of busulfan, applied in real-time. The process is technically complex and requires the very close cooperation of the teams involved. A strength, weakness, opportunity and threat (SWOT) analysis has been constructed; it fully supports continuous quality improvement to the triple benefit of the nursing chain, the patients and their environment. Several critical points were identified and corrected. The experiment strongly contributes to the safety and security of the medication circuit at the hospital and, improves the performance of allo-SCT. It also contributes to the protection of all actors in the health field and their working environment via a well-functioning quality management system.