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Background Nitric oxide (NO), a gaseous messenger with pleiotropic functions, plays a role in cancer, including breast cancer (BC). Considering the high permeability and leakiness of NO across tissues and the increased levels of NO recently reported in exhaled breath and blood of patients with lung cancer, we explored exhaled NO levels in patients with BC in a future perspective of non‐invasive cancer detection. Patients and Methods Fractional exhaled NO (FeNO) levels were detected in the breath of 192 women with BC and malignancy‐free controls employing a widely used point‐of‐care (POC)‐based system previously developed for asthma monitoring. Results FeNO levels were lower in BC patients compared to controls, with the lowest levels in women with HER2‐expressing tumors. In univariate and multivariate analyses and after adjustment for age, smoking, and asthma, this difference was not significant. The effects of smoking were not statistically significant, whereas asthmatic subjects had significantly higher levels of FeNO (p = 0.006). Neither menopause nor BMI had a significant impact on FeNO levels. Conclusion Our explorative work indicates that FeNO levels are heterogeneously detected in the breath of BC patients in the absence of confounding effects and are associated with the clinical characteristics of the disease. More sensitive detection of exhaled NO and larger cohorts enriched with ER negative BC are needed to further explore the potential of NO in non‐invasive detection of BC, either alone or in conjunction with other BC‐related volatile markers, and extending the NO measurement to blood or tissues.

Introduction In this paper, an analytical pipeline designed for untargeted lipidomic profiling in human plasma is proposed. The analytical pipeline was developed for case-control studies nested in prospective cohorts. Methods The procedure consisted of isopropanol protein precipitation followed by reverse phase liquid chromatography coupled to high resolution mass spectrometry and software-assisted data processing. The compounds are putatively annotated by matching experimental mass spectrometry data with spectral library data using LipidSearch software. The lipid profile of a pool of plasma samples from 10 healthy volunteers was detected in both positive and negative polarity modes. The impact of the chosen polarity on the number and quality of the lipid identification has been evaluated. Results More than 1000 lipids from 12 different classes were detected, 1150 in positive mode and 273 in negative mode. Nearly half of them were unambiguously identified by the software in positive mode, and about one-third in negative mode. The method repeatability was assessed on the plasma pool samples by means of variance components analysis. The intra- and inter-assay precision was measured for 10 lipids chosen among the most abundant found within the different lipid classes. The intra-assay coefficients of variation ranged from 2.56% to 4.56% while intra- and inter-day coefficients of variance never exceeded the 15% benchmark adopted. The lipidomic profiles of the 10 healthy volunteers were also investigated. Discussion This method detects a wide range of lipids and reports their degree of identification. It is particularly fit and well-designed for large case-control epidemiologic studies.

Silicon is the reference material of microelectronics, is readily available, relatively unexpensive, and its use may take profit of a fantastic technology. This may explain why a substantial effort has focused on improving its thermoelectric efficiency, either by top-down nanostructuring or through suitable processing. In this paper we report an analysis of the electronic transport properties of heavily boron-doped nanocrystalline silicon films. High-temperature thermal treatments are confirmed to remarkably increase its thermoelectric power factor. Electrical conductivity and Hall effect measurements were carried out over the temperature range 20–300 K along with Seebeck coefficient measurements. We provide evidence of the occurrence of low-temperature hopping conduction between impurity subbands. Dopant ionization was studied as a function of temperature. Freeze-out temperature was found to correlate with the Seebeck coefficient in agreement with Pisarenko equation. This brings to the conclusion that, while untreated samples are weakly degenerate, the thermal processing reverts them into non-degenerate semiconductors, in spite of the high doping level.