Fragrance monoterpenes are widely used commercially due to their pleasant scent. In previous studies, we have shown that air-exposed monoterpenes form hydroperoxides that are strong skin sensitizers. Methods for detection and quantification of the hydroperoxides in essential oils and scented products are thus desirable. Due to thermolability and low UV absorbance, this is a complicated task. We have recently developed a sensitive LC-ESI-MS method, but with limited structural information and separation efficiency for positional isomers and stereoisomers. In the present study, we investigated derivatization with a trimethyl silyl reagent and subsequent GC with electron ionization MS for the determination of monoterpene hydroperoxides. All investigated monoterpene hydroperoxides could be chromatographed as thermostable trimethyl silyl derivatives and yielded the fragment m/z 89 ([OSi(CH3)3](+)) at a higher extent compared to corresponding alcohols. Limonene-2-hydroperoxide and four other hydroperoxide isomers of limonene were separated and detected in sweet orange oil autoxidized for two months. The concentration of limonene-2-hydroperoxide isomers was found to be 19 μg/mg in total. Also isomers of linalyl acetate hydroperoxide and linalool hydroperoxide were detected in autoxidized petitgrain oil (two months). The presented GC-MS method showed concentrations in the same order as previous LC-MS/MS analysis of the same type of oils.

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PMV achieves comparable results to CSC both in the short and long term.

BackgroundPatients with severe aortic stenosis and concomitant active cancer (AC) are considered high-risk patients and usually are not allowed to undergo surgical valve replacement. Transcatheter aortic valve replacement (TAVR) may be an attractive option for them; however, little is known about the outcomes of TAVR in this subset of complex patients.Methods and resultsIn this meta-analysis, Medline, Cochrane Library and Scopus databases were searched (anytime up to April 2019) for studies evaluating the outcomes of TAVR in patients with or without AC. We assessed pooled estimates (with their 95% CIs) of the risk ratio (RR) for the all-cause mortality at the 30-day and 1-year follow-ups, a 4-point safety outcome (any bleeding, stroke, need for a pacemaker and acute kidney injury) and a 2-point efficacy outcome (device success and residual mean gradient (mean difference)). Three studies (5162 patients) were included. Of those patients, a total of 368 (7.1%) had AC. Apart from a significantly higher need for a postprocedural pacemaker (RR 1.29, 95% CI 1.06 to 1.58, p=0.01), TAVR in patients with AC resulted in similar outcomes for safety and efficacy at the 30-day follow-up compared with those without AC. Patients with AC experienced similar rates of the all-cause mortality at the 30-day follow-up compared with those without (RR 0.92, 95% CI 0.53 to 1.59, p=0.76); however, the all-cause mortality was significantly higher in patients with AC at the 1-year follow-up (RR 1.71, 95% CI 1.26 to 2.33, p=0.0006). This mortality difference was independent of cancer stage (advanced or limited) at the 30-day follow-up but not at the 1-year follow-up; only patients with limited cancer stages showed similar all-cause mortality rates compared with those without cancer at the 1-year follow-up (RR 1.22, 95% CI 0.79 to 1.91, p=0.37).ConclusionTAVR in patients with AC is associated with similar 30-day and potentially worse 1-year outcomes compared with those in patients without AC. The 1-year all-cause mortality appears to be dependent on the cancer stage. Involving a specialised oncologist who usually considers cancer stage in the decision-making process and applying additional preoperative scores such as frailty indices might refine the risk assessment process among these patients.PROSPERO registration numberCRD42019120416.

Transcatheter aortic valve replacement (TAVR) has recently been approved for use in patients who are at intermediate and low surgical risk. Moreover, recent years have witnessed a renewed interest in minimally invasive aortic valve replacement (miAVR). The present meta-analysis compared the outcomes of TAVR and miAVR in the management of aortic stenosis (AS). We conducted an electronic search across six databases from 2002 (TAVR inception) to December 2019. Data from relevant studies regarding the clinical and length of hospitalisation outcomes were extracted and analysed using R software. We identified a total of 11 cohort studies, of which seven were matched/propensity matched. Our analysis demonstrated higher rates of midterm mortality (≥1 year) with TAVR (risk ratio (RR): 1.93, 95% CI: 1.16 to 3.22), but no significant differences with respect to 1 month mortality (RR: 1.00, 95% CI: 0.55 to 1.81), stroke (RR: 1.08, 95% CI: 0.40 to 2.87) and bleeding (RR: 1.45, 95% CI: 0.56 to 3.75) rates. Patients undergoing TAVR were more likely to experience paravalvular leakage (RR: 14.89, 95% CI: 6.89 to 32.16), yet less likely to suffer acute kidney injury (RR: 0.38, 95% CI: 0.21 to 0.69) compared with miAVR. The duration of hospitalisation was significantly longer in the miAVR group (mean difference: 1.92 (0.61 to 3.24)). Grading of Recommendations Assessment, Development and Evaluation assessment revealed ≤moderate quality of evidence in all outcomes. TAVR was associated with lower acute kidney injury rate and shorter length of hospitalisation, yet higher risks of midterm mortality and paravalvular leakage. Given the increasing adoption of both techniques, there is an urgent need for head-to-head randomised trials with adequate follow-up periods.