300 research outputs found
Diel rhythm of volatile emissions from males and females of the olive fruit fly Bactrocera oleae using PTR-ToF and GC–MS
The olive fruit fly Bactrocera oleae, is the major key pest of olive groves worldwide. As an odor-driven species, its intraspecific communication has been thoroughly investigated, yielding a combination of spiroacetals, esters and hydrocarbons. However, its management with pheromone is still restricted to olean, the major pheromone component. Given the crucial role of circadian rhythm and pheromone blends in mediating flies reproductive behavior compared to single compounds, B. oleae headspace chemical profile was carefully examined, through the combination of Proton Transfer Reaction Time of Flight Mass Spectrometry (PTR-ToF) and Gas Chromatography coupled with Mass Spectrometry (GC–MS). This novel approach aimed at continuously investigating the temporal scale of volatilome profile of B. oleae individuals, as well as the determination of new candidate sexborne compounds (particularly those emitted in traces or having low molecular weight), that may be relevant to the fly’s chemical communication and were unreported due to limitations of frequently used analytical techniques. Our results describe the dynamics and diversity of B. oleae chemical profile, highlighting the emission of 90 compounds, with clear diel rhythm of release, of known pheromone components of B. oleae (e.g., olean, alphapinene and muscalure) and new candidates. In contrast to ammonia, acetaldehyde and muscalure, which were highly emitted during the afternoon by males and mixed groups, olean was mostly released by mature females and mixed groups, with a peak of emission during early-morning and afternoon. This emission of olean around dawn is reported for the first time, suggesting early-morning mating activity in B. oleae. Furthermore, esters, such as methyl tetradecanoate, which had been earlier identified as a pheromone for B. oleae, did not exhibit any discernible release patterns. These findings are the first to demonstrate the emission of chemicals, which are only produced when males and females are close to one another, with an emission peak during the afternoon (mating period), and that may have aphrodisiac properties for B. oleae males. These results emphasize the relevance of compounds with distinct diel rhythm and address their potential function as intraspecific messengers, according to their source and timing of releas
Metal release under anaerobic conditions of urban soils of four European cities
Urban soil contamination may represent an environmental threat in view of their proximity to humans. The ecological homogenization of urban areas has been postulated, and as the sources of pollution are the same in most European cities, it is possible that soil contamination is another factor of convergence. The current climate change with consequent increase of extreme rain events may affect the mobility of potentially toxic elements (PTE) thus increasing the risks. If the soil is submerged, Eh decreases and causes the solubilization of Fe and Mn oxides, which are important carriers of PTE. We compared the release of Cu, Pb, and Zn from 48 soils of four cities (namely Glasgow, Ljubljana, Sevilla, and Torino) when submerged for up to 30 days. A decrease of the redox potential was observed in all soils after a few days and an increase of Mn and then Fe in solution. Cu, Pb, and Zn were consequently released to the solution according to the general soil contamination. Despite the marked differences in soil properties, the reaction to anaerobiosis appeared to be similar in all samples indicating that waterlogging of urban soil contaminated with PTE may pose a serious environmental risk and substantiating the hypothesis of ecological convergence
PTR-ToF-MS for the online monitoring of alcoholic fermentation in wine: assessment of VOCs variability associated with different combinations of Saccharomyces/non-Saccharomyces as a case-study
7openInternationalItalian coauthor/editorThe management of the alcoholic fermentation (AF) in wine is crucial to shaping product quality. Numerous variables (e.g., grape varieties, yeast species/strains, technological parameters) can affect the performances of this fermentative bioprocess. The fact that these variables are often interdependent, with a high degree of interaction, leads to a huge ‘oenological space’ associated with AF that scientists and professionals have explored to obtain the desired quality standards in wine and to promote innovation. This challenge explains the high interest in approaches tested to monitor this bioprocess including those using volatile organic compounds (VOCs) as target molecules. Among direct injection mass spectrometry approaches, no study has proposed an untargeted online investigation of the diversity of volatiles associated with the wine headspace. This communication proposed the first application of proton-transfer reaction-mass spectrometry coupled to a time-of-flight mass analyzer (PTR-ToF-MS) to follow the progress of AF and evaluate the impact of the different variables of wine quality. As a case study, the assessment of VOC variability associated with different combinations of Saccharomyces/non-Saccharomyces was selected. The different combinations of microbial resources in wine are among the main factors susceptible to influencing the content of VOCs associated with the wine headspaces. In particular, this investigation explored the effect of multiple combinations of two Saccharomyces strains and two non-Saccharomyces strains (belonging to the species Metschnikowia pulcherrima and Torulaspora delbrueckii) on the content of VOCs in wine, inoculated both in commercial grape juice and fresh grape must. The results demonstrated the possible exploitation of non-invasive PTR-ToF-MS monitoring to explore, using VOCs as biomarkers, (i) the huge number of variables influencing AF in wine, and (ii) applications of single/mixed starter cultures in wine. Reported preliminary findings underlined the presence of different behaviors on grape juice and on must, respectively, and confirmed differences among the single yeast strains ‘volatomes’. It was one of the first studies to include the simultaneous inoculation on two non-Saccharomyces species together with a S. cerevisiae strain in terms of VOC contribution. Among the other outcomes, evidence suggests that the addition of M. pulcherrima to the coupled S. cerevisiae/T. delbrueckii can modify the global release of volatiles as a function of the characteristics of the fermented matrixopenBerbegal, C.; Khomenko, I.; Russo, P.; Spano, G.; Fragasso, M.; Biasioli, F.; Capozzi, V.Berbegal, C.; Khomenko, I.; Russo, P.; Spano, G.; Fragasso, M.; Biasioli, F.; Capozzi, V
Optimization of gas sensors measurements by dynamic headspace analysis supported by simultaneous direct injection mass spectrometry
Dynamic headspace extraction is frequently used in gas sensors measurements. The procedure may introduce artefacts but its influence in sensor signals interpretation is rarely considered. In this paper, taking advantage of the on-line combination of a quartz microbalance gas sensor array with a proton transfer reaction mass spectrometer, we have been able to track the evolution of the concentration of volatile compounds along 75 s of extraction of the headspace of differently treated tomato pastes. Proton transfer reaction mass spectrometer signals show that VOCs are characterized by a large diversity of the evolution of the concentration. VOCs kinetics has been described by an electric equivalent circuit model. On the other hand, sensor signals continuously grow approaching a steady value. The contrasting behaviour between sensors signals and the concentration of most of VOCs is explained considering that water is the dominant component in the tomato paste sample and that water is one of those compounds whose concentration in the sensor cell steadily grows. Analysis of variance show that sensors signals achieve the largest separation between classes when the concentration of VOCs in the sensor cell reached its peak. Thus, although the sensor signals continue to rise their information content decays. This finding suggests that measurement protocols need to be adjusted according to the properties of the sample and that the actual measurement times could be much shorter than those predicted from the behaviour of sensor signal
Simultaneous Proton Transfer Reaction-Mass Spectrometry and electronic nose study of the volatile compounds released by Plasmodium falciparum infected red blood cells in vitro
The discovery that Volatile Organic Compounds (VOCs) can be biomarkers for several diseases has led to the conception of their possible application as diagnostic tools. In this study, we aimed at defining of diagnostic signatures for the presence of malaria transmissible stages in infected individuals. To do this, we compared VOCs released by asexual and sexual stage cultures of Plasmodium falciparum, the deadliest species of malaria, with those emitted by uninfected red blood cells (RBCs). VOC analysis was carried out with an innovative set-up, where each sample was simultaneously analysed by proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS) and an electronic nose. PTR-Tof-MS results show that sexual stages are characterized by a larger emission of hexanal, compared with uninfected or asexual stage-infected RBCs, which makes them clearly identifiable. PTR-Tof-MS analysis also detected differences in VOC composition between asexual stages and uninfected RBCs. These results have been substantially replicated by the electronic nose analysis and may open the possibility to develop sensitive and easy-to-use devices able to detect sexual parasite stages in infected individuals. This study also demonstrates that the combination of mass spectrometry with electronic noses is a useful tool to identify markers of diseases and to support the development of optimized sensors
Mesonephric-Like Adenocarcinomas a Rare Tumor: The Importance of Diagnosis
Mesonephric-like adenocarcinomas (MLA) are rare neoplasms that arise in the uterine body and ovary and have been added to the World Health Organisation’s recent 2020 classification of female genital cancers. The pathogenesis of MLA is unknown and it remains debated whether they represent mesonephric carcinomas (Wolffian) arising in the endometrium/ovary or endometrioid carcinomas (Müllerian) closely mimicking mesonephric carcinomas. Here we report the case of a 57-year-old woman with an initial misdiagnosis of endometrioid adenocarcinoma on diagnostic biopsy. The patient came to our clinical evaluation for the appearance of menometrorrhagia complicated by anemia for several months. Therefore, she underwent pelvic echo-flowmetry, with indication for diagnostic hysteroscopy with endometrial biopsy, which yielded a positive result for endometrioid endometrial adenocarcinoma. Following staging CT scan and targeted examinations on pulmonary findings, the patient underwent surgery with surprise of definitive diagnosis deponent for endometrial MLA. Our intention is to establish a brief review of the scientific evidence in the literature and the tools available for a correct histological diagnosis, in the light of the scant anatomopathological evidence. Our question gives rise to the motive for the publication: is immunohistochemistry the right way to resolve the diagnostic error at histology, which is usually the only source of diagnostic certainty? This case is intended to alert of diagnostic error that risked having the patient treated as a neoplasm with a favorable prognosis and low degree of aggressiveness instead of for a very aggressive and poor prognosis tumor such as MLA
Room temperature ammonia gas sensor based on p-type-like V2O5 nanosheets towards food spoilage monitoring
Gas sensors play an important role in many areas of human life, including the monitoring of production processes, occupational safety, food quality assessment, and air pollution monitoring. Therefore, the need for gas sensors to monitor hazardous gases, such as ammonia, at low operating temperatures has become increasingly important in many fields. Sensitivity, selectivity, low cost, Citation: Van Duy, L.; Nguyet, T.T.; Le, D.T.T.; Van Duy, N.; Nguyen, H.; Biasioli, F.; Tonezzer, M.; Di Natale, C.; Hoa, N.D. Room Temperature AmmoniaGasSensor Based on p-Type-like V2O5 Nanosheets towards Food Spoilage Monitoring. Nanomaterials 2023, 13, 146. https:// doi.org/10.3390/nano13010146 Academic Editors: Sergei Kulinich and Li Hai Received: 17 November 2022 Revised: 23 December 2022 Accepted: 24 December 2022 Published: 28 December 2022 Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). and ease of production are crucial characteristics for creating a capillary network of sensors for the protection of the environment and human health. However, developing gas sensors that are not only efficient but also small and inexpensive and therefore integrable into everyday life is a difficult challenge. In this paper, we report on a resistive sensor for ammonia detection based on thin V2O5 nanosheets operating at room temperature. The small thickness and porosity of the V2O5 nanosheets give the sensors good performance for sensing ammonia at room temperature (RT), with a relative change of resistance of 9.4% to 5 ppm ammonia (NH3) and an estimated detection limit of 0.4 ppm. The sensor is selective with respect to the seven interferents tested; it is repeatable and stable over the long term (four months). Although V2O5 is generally an n-type semiconductor, in this case the nanosheets show a p-type semiconductor behavior, and thus a possible sensing mechanism is proposed. The device’s performance, along with its size, low cost, and low power consumption, makes it a good candidate for monitoring freshness and spoilage along the food supply chai
Applications of Direct Injection Soft Chemical Ionisation-Mass Spectrometry for the Detection of Pre-blast Smokeless Powder Organic Additives
Analysis of smokeless powders is of interest from forensics and security perspectives. This article reports the detection of smokeless powder organic additives (in their pre-detonation condition), namely the stabiliser diphenylamine and its derivatives 2-nitrodiphenylamine and 4-nitrodiphenylamine, and the additives (used both as stabilisers and plasticisers) methyl centralite and ethyl centralite, by means of swab sampling followed by thermal desorption and direct injection soft chemical ionisation-mass spectrometry. Investigations on the product ions resulting from the reactions of the reagent ions H3O+ and O2+ with additives as a function of reduced electric field are reported. The method was comprehensively evaluated in terms of linearity, sensitivity and precision. For H3O+, the limits of detection (LoD) are in the range of 41-88 pg of additive, for which the accuracy varied between 1.5 and 3.2%, precision varied between 3.7 and 7.3% and linearity showed R20.9991. For O2+, LoD are in the range of 72 to 1.4 ng, with an accuracy of between 2.8 and 4.9% and a precision between 4.5 and 8.6% and R20.9914. The validated methodology was applied to the analysis of commercial pre-blast gun powders from different manufacturers.(VLID)4826148Accepted versio
CUP-syndrome: Inguinal high grade serous ovarian carcinoma lymph node metastases with unknown primary origin – a case report and literature review
Objective: High-grade serous ovarian carcinoma (HGSC) often presents lymph node involvement. According to the paths of lymphatic drainage, the most common site of nodal metastasis is in the aortic area. However, pelvic lymph nodes are also involved and inguinal metastases are less frequent. Methods: Our report concerns the case of a 78-year-old woman with an inguinal lymph node relapse of HGSC, with the prior positivity of a right inguinal lymph node, after the primary surgery. Ovaries and tubes were negative on histological examination. A comprehensive search of the literature published from January 2000 to October 2021 was conducted on PubMed and Scopus. The papers were selected following the PRISMA guidelines. Nine retrospective studies were evaluated. Results: Overall, 67 studies were included in the initial search. Applying the screening criteria, 36 articles were considered eligible for full-text reading of which, after applying the exclusion criteria, 9 studies were selected for the final analysis and included in the systematic review. No studies were included for a quantitative analysis. We divided the results according to the relapse location: loco-regional, abdominal, and extra-abdominal recurrence. Conclusions: Inguinal node metastasis is a rare but not unusual occurrence in HGSC. A reasonable level of suspicion should be maintained in patients with inguinal adenopathy and high CA125 values, especially in women with a history of gynecologic surgery, even in the absence of negative imaging for an ovarian origin
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