Validation of Mitra® VAMS® as a blood collection technique for trace elements analysis using ICP-MS/MS

Background: Clinical dosage of toxic and essential elements in blood is well established and the collection method is still by venipuncture. This method has drawbacks and is not suited for everyone. Volumetric absorptive microsampling (VAMS) has been shown to have advantages over venipuncture. Materials & methods: Using inductively coupled plasma tandem mass spectrometry, a method for quantifying elements in whole blood sampled on VAMS was developed/validated. Method's performance was assessed by comparison with whole blood results. Results: Validation and performance assessment tests tend to show that most of the targeted elements provides accurate and reproducible results comparing to a method of reference. Conclusion: Overall, VAMS presents good preliminary results to eventually become an alternative to venipuncture for blood sampling for some trace elements analysis purposes.

Transformation d’un restaurant hospitalier en unité de soins critiques de courte durée

En mars 2021, l’Île-de-France a connu une nouvelle vague de Covid-19. Face à une projection épidémique faisant craindre un dépassement des capacités, la cellule de crise de l’Assistance publique-Hôpitaux de Paris a validé la mise en oeuvre du projet Météor. Météor est la transformation d’un restaurant du personnel du CHU Pitié-Salpêtrière en réanimation d’accueil et d’orientation de patients Covid-19 avant qu’ils ne soient adressés à des réanimations plus pérennes sur site ou en dehors. Cette démarche n’ayant jamais été pensée auparavant, tout était à construire. Une équipe projet composée d’un cadre de santé, d’un médecin, d’un ingénieur et d’un directeur a piloté sa mise en oeuvre. Le projet s’est voulu modulable, démontable et intégré comme une ressource zonale. En à peine 15 jours, l’unité était opérationnelle. L’organisation des soins a été simplifiée et standardisée au maximum pour que chaque personnel puisse assurer sa mission en sérénité malgré un contexte et des lieux inhabituels. L’efficacité de la mise en oeuvre du projet est liée à l’expertise des équipes en place et au caractère multiprofessionnel de l’équipe projet. Le point de fragilité s’est avéré être les ressources humaines. La constitution d’un corps de réserve sanitaire de personnels de soins critiques est nécessaire pour anticiper la prochaine crise.

Determination of glyphosate, glufosinate and their major metabolites in urine by the UPLC-MS/MS method applicable to biomonitoring and epidemiological studies

The preoccupation concerning glyphosate (GLYP) has rapidly grown over recent years, and the availability of genetically modified crops that are resistant to GLYP or glufosinate (GLUF) has increased the use of these herbicides. The debate surrounding the carcinogenicity of GLYP has raised interest and the desire to gain information on the level of exposure of the population. GLYP and aminomethylphosphonic acid (AMPA) are commonly simultaneously analysed. GLUF is sometimes also monitored, but its major metabolite, 3-[hydroxy(methyl)phosphinoyl]propionic acid (3MPPA), is rarely present in the method. Using a pentafluorobenzyl derivative to extract the analytes from human urine, we present a method that contains four important analytes to monitor human exposure to GLYP and GLUF. The use of the flash freeze technique speeds up the extraction process and requires less organic solvent than conventional liquid-liquid extraction. The limits of detection in the low μg/L range enable the use of this method for epidemiological studies. The results obtained for 35 volunteers from the Quebec City area are presented with the results from multiple interlaboratory comparisons (G-EQUAS, HBM4EU and OSEQAS). This methodology is currently being used in the Maternal-Infant Research on Environmental Chemicals (MIREC-ENDO) study and in the Canadian Health Measures Survey (CHMS).

Quantification of titanium dioxide nanoparticles in human urine by single-particle ICP-MS

The increasing use of titanium dioxide nanoparticles in daily use consumer products such as cosmetics, personal care products, food additives, and even medicine has led to growing concerns regarding human safety. It would be ideal to track exposure to this emerging nanopollutant, for example through bioassays, however, so far nanoparticle assessment in biological matrices such as urine remains challenging. The lack of data is mainly due to the limitations of the current metrology, but also to the low expected concentration in human samples. In this study, a quantification method for titanium dioxide nanoparticles in urine has been developed and validated following the ISO/CEI 17025:2017 guidelines. The detection limit for titanium dioxide nanoparticle mass concentration by single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS) was 0.05 ng mL^-1. The particle size limit was determined using three different approaches, with the highest calculated limit value approaching 50 nm. Repeatability and reproducibility of 14% and 18% respectively were achieved for particle mass concentration, and 6% for both parameters for particle size determination. Method trueness and recovery were 98% and 84%, respectively.

Stability issues in the determination of 19 urinary (free and conjugated) monohydroxy polycyclic aromatic hydrocarbons

Data on the stability of monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs; metabolites of PAHs) in urine are needed in order to effectively study the effects of PAHs in the body, but the relevant data are not available in the literature. Therefore, in this work, we investigated the stability of OH-PAHs in urine. For each OH-PAH studied, the free form (as opposed to the conjugated form) comprised <10 % of the total OH-PAH in urine samples obtained from a normal population, except for 9-OH-phenanthrene (where the free form represented 22.2 % of the total 9-OH-phenanthrene). 1-Naphthol and 9-OH-phenanthrene were found to be less stable in their free forms in urine than in their conjugated forms when the urine samples were stored at 4 °C or room temperature. Free 3-OH-fluoranthene was also very unstable at 4 °C or room temperature. The conjugated forms of the OH-PAHs were more stable than their corresponding free forms. However, the free and conjugated forms of all the OH-PAHs were stable in urine at -20 °C and -80 °C. A freeze and thaw assay also revealed that freezing and thawing had minimal impact on the stability of the OH-PAHs in urine. For the derivatized extracts, storing the samples under an argon atmosphere at 4 °C was found to maintain sample integrity. In order to measure the stabilities of 19 hydroxylated metabolites of PAHs in urine, we developed a method with sensitivity in the low pg/mL range using nine labeled internal standards. This method combined enzymatic deconjugation with liquid-liquid extraction, derivatization with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA), and gas chromatography/tandem mass spectrometry (GC-MS/MS). Graphical abstract Stability of the conjugated forms of the OH-PAHs versus free forms (e.g. 1-naphthol).

[KTP-80 laser endovaporisation of prostate symptomatic hypertrophy in patients under anticoagulant and/or antiagregant therapy]

Our population is ageing along with the rate of cardiovascular pathologies, which frequently require administration of antithrombotic treatments. Consequently, prostatic surgery becomes increasingly delicate. Thus per- and post-operative macroscopic hematuria contributes significantly to the duration of hospitalization and the morbidity of conventional surgery of symptomatic prostate hypertrophy. Moreover, these patients require transient suspension of their anticoagulation or anti-aggregation treatment. The recent KTP-80 laser limits post-operative hematuria and allows to operate on the growing population of patients under antiagregant and/or anticoagulant therapy. We review in these patients the operative modalities and the results of this surgery, in comparison with transurethral resection of the prostate.

Brown fat in breast cancer patients: analysis of serial 18F-FDG PET/CT scans

PURPOSE

It has recently been suggested that FDG accumulation in the brown adipose tissue varies as a function of age, sex and outdoor temperature. The aim of this study was to assess changes in FDG uptake in brown fat in patients based on serial PET/CT scans and to compare our results with previous findings.

METHODS

Early response to neoadjuvant chemotherapy in 33 female breast cancer patients was assessed by FDG PET. Five PET/CT scans were performed for each patient. PET/CT images were analysed retrospectively. PET scans were considered positive when diffuse, symmetrical, abnormal "USA" (uptake in supraclavicular area) fat was detected.

RESULTS

A total of 163 PET images were analysed. Seventy-four PET scans (45%) revealed abnormal FDG uptake in the supraclavicular area. These foci were present on uncorrected and attenuation-corrected images. FDG uptake was identical on all five scans in only five patients. No significant relationship was found between abnormal FDG uptake and outdoor temperature, age or time interval between chemotherapy and PET. Abnormal FDG uptake in the neck seemed to predominantly occur in patients with a low body mass index (p<0.05). Most significant changes in the PET/CT scan results were observed during chemotherapy with docetaxel (p<0.05). When observed, bilateral uptake in the neck was more intense than background uptake (p<0.00001).

CONCLUSION

This study shows that FDG uptake in the neck varies as a function of time, that it is unrelated to age or outdoor temperature, and that bilateral uptake is generally intense.