Volatile organic compound profiling to explore primary graft dysfunction after lung transplantation

Primary graft dysfunction (PGD) is a major determinant of morbidity and mortality following lung transplantation. Delineating basic mechanisms and molecular signatures of PGD remain a fundamental challenge. This pilot study examines if the pulmonary volatile organic compound (VOC) spectrum relate to PGD and postoperative outcomes. The VOC profiles of 58 bronchoalveolar lavage fluid (BALF) and blind bronchial aspirate samples from 35 transplant patients were extracted using solid-phase-microextraction and analyzed with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry. The support vector machine algorithm was used to identify VOCs that could differentiate patients with severe from lower grade PGD. Using 20 statistically significant VOCs from the sample headspace collected immediately after transplantation (< 6 h), severe PGD was differentiable from low PGD with an AUROC of 0.90 and an accuracy of 0.83 on test set samples. The model was somewhat effective for later time points with an AUROC of 0.80. Three major chemical classes in the model were dominated by alkylated hydrocarbons, linear hydrocarbons, and aldehydes in severe PGD samples. These VOCs may have important clinical and mechanistic implications, therefore large-scale study and potential translation to breath analysis is recommended

Enhanced Characterization of the Smell of Death by Comprehensive Two-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry (GCxGC-TOFMS)

Soon after death, the decay process of mammalian soft tissues begins and leads to the release of cadaveric volatile compounds in the surrounding environment. The study of postmortem decomposition products is an emerging field of study in forensic science. However, a better knowledge of the smell of death and its volatile constituents may have many applications in forensic sciences. Domestic pigs are the most widely used human body analogues in forensic experiments, mainly due to ethical restrictions. Indeed, decomposition trials on human corpses are restricted in many countries worldwide. This article reports on the use of comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOFMS) for thanatochemistry applications. A total of 832 VOCs released by a decaying pig carcass in terrestrial ecosystem, i.e. a forest biotope, were identified by GCxGC-TOFMS. These postmortem compounds belong to many kinds of chemical class, mainly oxygen compounds (alcohols, acids, ketones, aldehydes, esters), sulfur and nitrogen compounds, aromatic compounds such as phenolic molecules and hydrocarbons. The use of GCxGC-TOFMS in study of postmortem volatile compounds instead of conventional GC-MS was successful

LES EXTREMES NIVOMETRIQUES DANS LES ALPES ITALIENNES : ANALYSE DES DONNEES DE DEUX STATIONS DU MONTE CANIN(ALPES IULIENNEES - FRIOUL) ET SITUATIONS SYNOPTIQUES RESPONSABLES DES CHUTES DE NEIGE

Extreme snow levels in the Italian Alps. Analysis of data from two stations in Monte Canin (Julian Alps - Frioul) and representative synoptic situations for snowfalls. The Julian Alps are the most important "water castle" of the Italian territory; she’s are situated on the border with Slovenia and to be ready for about 50 kilometres’ with west-east direction, less than 60 kilometres’ from the coast of the Adriatic Sea. The Mediterranean air masses, triggered by depressions positioned on the Atlantic or centred in the Genoa Gulf, they will rise and determine heavy and recurring rainfall; very abundant throughout the year. From mid November until the mid April, more than 1200 meters, the precipitation are almost exclusively snowy and the snowfall are exceptionally heavy; so in Canin massif two glaciers are found and descending to 1900 meters about. The notable thickness of snow to the ground and the prolonged snow cover favours a very long ski season bath, at same time, determine a frequent releases of large avalanches, that is harmful to the tourism