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1.
Antibiotics (Basel) ; 12(10)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37887188

RESUMO

Neonatal sepsis is an important cause of morbidity and mortality in neonatal intensive care units (NICUs). Continuous evaluation of antimicrobial resistance (AMR) profiles is advised to implement antimicrobial stewardship (AMS) programs and establish effective empiric antibiotic protocols. AMS may reduce AMR in NICUs and improve sepsis outcomes. In this retrospective observational study, we report data on culture-positive neonatal sepsis, assessing differences after the implementation of an AMS program (2011-2016 vs. 2017-2022). A total of 215 positive bacterial cultures from 169 infants were retrieved, with 79 early-onset (36.7%) and 136 late-onset (63.3%) sepsis episodes. Frequent causative agents for early-onset sepsis were S. agalactiae and E. coli, all susceptible to empiric treatment. Late-onset sepsis was mainly caused by Enterobacterales and S. aureus. Aminoglycosides, cefotaxime, and piperacillin-tazobactam resistance among Enterobacterales was substantially low; S. aureus was mostly susceptible to oxacillin and vancomycin. There were no differences in mortality and multidrug-resistant pathogens rates between the two study periods. There were five episodes of fungal late-onset sepsis, mostly due to C. albicans, of which one was fatal. The microbial distribution pattern and AMR profiles overlapped with other European studies. Because susceptibility patterns are rapidly changing worldwide, with the emerging threat of Methicillin-resistant S. aureus and extended-spectrum beta-lactamases producers, infection prevention and control practices and AMS strategies require continuous optimization to limit selection pressure and AMR escalation.

2.
Molecules ; 25(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321824

RESUMO

Despite promising results obtained in the early diagnosis of several pathologies, breath analysis still remains an unused technique in clinical practice due to the lack of breath sampling standardized procedures able to guarantee a good repeatability and comparability of results. The most diffuse on an international scale breath sampling method uses polymeric bags, but, recently, devices named Mistral and ReCIVA, able to directly concentrate volatile organic compounds (VOCs) onto sorbent tubes, have been developed and launched on the market. In order to explore performances of these new automatic devices with respect to sampling in the polymeric bag and to study the differences in VOCs profile when whole or alveolar breath is collected and when pulmonary wash out with clean air is done, a tailored experimental design was developed. Three different breath sampling approaches were compared: (a) whole breath sampling by means of Tedlar bags, (b) the end-tidal breath collection using the Mistral sampler, and (c) the simultaneous collection of the whole and alveolar breath by using the ReCIVA. The obtained results showed that alveolar fraction of breath was relatively less affected by ambient air (AA) contaminants (p-values equal to 0.04 for Mistral and 0.002 for ReCIVA Low) with respect to whole breath (p-values equal to 0.97 for ReCIVA Whole). Compared to Tedlar bags, coherent results were obtained by using Mistral while lower VOCs levels were detected for samples (both breath and AA) collected by ReCIVA, likely due to uncorrected and fluctuating flow rates applied by this device. Finally, the analysis of all data also including data obtained by explorative analysis of the unique lung cancer (LC) breath sample showed that a clean air supply might determine a further confounding factor in breath analysis considering that lung wash-out is species-dependent.


Assuntos
Testes Respiratórios/métodos , Adulto , Testes Respiratórios/instrumentação , Análise de Dados , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Projetos de Pesquisa , Manejo de Espécimes , Compostos Orgânicos Voláteis/análise , Adulto Jovem
3.
Cancers (Basel) ; 12(5)2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32429446

RESUMO

Malignant pleural mesothelioma (MPM) is a rare neoplasm, mainly caused by asbestos exposure, with a high mortality rate. The management of patients with MPM is controversial due to a long latency period between exposure and diagnosis and because of non-specific symptoms generally appearing at advanced stage of the disease. Breath analysis, aimed at the identification of diagnostic Volatile Organic Compounds (VOCs) pattern in exhaled breath, is believed to improve early detection of MPM. Therefore, in this study, breath samples from 14 MPM patients and 20 healthy controls (HC) were collected and analyzed by Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC/MS). Nonparametric test allowed to identify the most weighting variables to discriminate between MPM and HC breath samples and multivariate statistics were applied. Considering that MPM is an aggressive neoplasm leading to a late diagnosis and thus the recruitment of patients is very difficult, a promising data mining approach was developed and validated in order to discriminate between MPM patients and healthy controls, even if no large population data are available. Three different machine learning algorithms were applied to perform the classification task with a leave-one-out cross-validation approach, leading to remarkable results (Area Under Curve AUC = 93%). Ten VOCs, such as ketones, alkanes and methylate derivates, as well as hydrocarbons, were able to discriminate between MPM patients and healthy controls and for each compound which resulted diagnostic for MPM, the metabolic pathway was studied in order to identify the link between VOC and the neoplasm. Moreover, five breath samples from asymptomatic asbestos-exposed persons (AEx) were exploratively analyzed, processed and tested by the validated statistical method as blinded samples in order to evaluate the performance for the early recognition of patients affected by MPM among asbestos-exposed persons. Good agreement was found between the information obtained by gold-standard diagnostic methods such as computed tomography CT and model output.

4.
Cancers (Basel) ; 11(6)2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31207975

RESUMO

Malignant pleural mesothelioma (MPM) is a rare neoplasm related to asbestos exposure and with high mortality rate. The management of patients with MPM is complex and controversial, particularly with regard to early diagnosis. In the last few years, breath analysis has been greatly implemented with this aim. In this review the strengths of breath analysis and preliminary results in searching breath biomarkers of MPM are highlighted and discussed, respectively. Through a systematic electronic literature search, collecting papers published from 2000 until December 2018, fifteen relevant scientific papers were selected. All papers considered were prospective, comparative, observational case-control studies although every single one pilot and based on a relatively small number of samples. The identification of diagnostic VOCs pattern, through breath sample characterization and the statistical data treatment, allows to obtain a strategic information for clinical diagnostics. To date the collected data provide just preliminary information and, despite the promising results and diagnostic accuracy, conclusions cannot be generalized due to the limited number of individuals included in each cohort study. Furthermore none of studies was externally validated, although validation process is a necessary step towards clinical implementation. Breathomics-based biomarker approach should be further explored to confirm and validate preliminary findings and to evaluate its potential role in monitoring the therapeutic response.

5.
Molecules ; 23(9)2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30200346

RESUMO

Low temperature treatments commonly applied to seafood products have been shown to influence their phospholipid (PL) profile through enzymatic hydrolysis. In the present study, the generation of lysophospholipids (LPL) resulting from this process was systematically investigated for selected, commercially relevant seafood products, namely oysters, clams, octopuses, and shrimps. These products were subjected to thermal treatments like refrigeration or freezing after being purchased as fresh, defrozen, or frozen products depending on the case. The coupling between hydrophilic interaction liquid chromatography (HILIC) and electrospray ionization with high resolution/accuracy Fourier transform mass spectrometry (ESI-FTMS) was exploited to evaluate the PL profile of the cited products, especially the incidence of LPL related to the two main PL classes of seafood products-phosphatidylcholines (PC) and phosphatidylethanolamines (PE)-in the lipid extracts. The lyso forms of PE (LPE) were found to be generally more sensitive than those of PC (LPC) to thermal treatments, usually exhibiting a significant increase upon prolonged refrigeration at 4 °C in all types of investigated products except European flat oysters. Moreover, the distinction between fresh and frozen or defrozen products could be achieved in the case of octopuses and shrimps, respectively.


Assuntos
Análise de Fourier , Interações Hidrofóbicas e Hidrofílicas , Lisofosfolipídeos/análise , Alimentos Marinhos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Temperatura , Cromatografia Líquida , Fosfatidilcolinas/análise
6.
Food Chem ; 255: 309-322, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29571481

RESUMO

An unprecedented characterization of free fatty acids (FFA) in the lipid extracts of fresh or thermally treated mussels of sp. Mytilus galloprovincialis, including up to 128 saturated, mono- or poly-unsaturated and 63 oxidized (i.e., modified by hydroxylic, carbonylic and/or epoxylic groups) compounds, was achieved using reverse phase chromatography coupled to electrospray ionization-Fourier transform single and tandem mass spectrometry (RPC-ESI-FTMS,MS/MS). Subsequent Principal Components Analysis (PCA) evidenced several effects of thermal treatments on the mussel FFA profiles. In particular, death-inducing low temperature treatments (freezing at -16 °C or refrigeration at 4 °C for several days) induced a peculiar increase in the incidence of FFA, whereas the effect was absent in mussels undergoing death upon prolonged storage at room temperature (25 °C, 6 h) or fast cooking (100 °C, 5 min). Alive mussels, either fresh or resulting from short term (up to 48 h) refrigeration were actually indistinguishable by PCA, although subtle seasonal effects were observed.


Assuntos
Ácidos Graxos não Esterificados/análise , Mytilus/química , Alimentos Marinhos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Cromatografia Líquida/métodos , Temperatura Alta , Oxirredução , Fatores de Tempo
7.
J Mass Spectrom ; 53(1): 1-20, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28892241

RESUMO

A systematic characterization of phosphatidylcholines and phosphatidylethanolamines in mussels of sp Mytilus galloprovincialis was performed by high-efficiency hydrophilic interaction liquid chromatography combined with electrospray ionization and Fourier transform mass spectrometry (FTMS), based on a quadrupole-Orbitrap hybrid spectrometer. The FTMS/MS experiments under high collisional energy dissociation conditions, complemented by low-energy collisionally induced dissociation MSn (n = 2,3) experiments, performed in a linear ion trap mass spectrometer, were exploited for structural elucidation purposes. The described approach led to an unprecedented characterization of the mussel phospholipidome, with 185 phosphatidylcholines and 131 phosphatidylethanolamines species recognized, distributed among diacylic, plasmanylic, and plasmenylic forms. This was the starting point for the evaluation of the effects of season (in particular, of sea temperature) on the profile of those phospholipids. To this aim, a set of mussel samples retrieved from commercial sources in different periods of the year was considered. Principal component analysis revealed a clear separation between samples collected in periods characterized by cold, intermediate, or warm sea temperatures, respectively. In particular, an enrichment in phospholipids containing unsaturated side chains was observed in mussels collected from cold seawaters (winter-early spring), thus confirming the general model previously elaborated to explain the adaptation of marine invertebrates, including some bivalve molluscs, to low temperatures. On the other hand, relevant levels of plasma(e)nylic and acylic phospholipids bearing either saturated or non-methylene-interrupted side chains were found in mussels collected in warm seawaters (typical of summer and early autumn, at Italian latitudes). This finding opened interesting perspectives towards the development of strategies able to prevent global warming-related mussel losses in aquacultural plants.


Assuntos
Mytilus/química , Fosfolipídeos/análise , Animais , Cromatografia Líquida , Análise de Fourier , Interações Hidrofóbicas e Hidrofílicas , Estações do Ano , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
8.
Sci Rep ; 6: 32452, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27578427

RESUMO

In spite of its positive repercussions on nutrition and environment, faba bean still remains an underutilized crop due to the presence of some undesired compounds. The pyrimidine glycosides vicine and convicine are precursors of the aglycones divicine and isouramil, the main factors of favism, a genetic condition which may lead to severe hemolysis after faba bean ingestion. The reduction of vicine and convicine has been targeted in several studies but little is known about their degradation. In this study, the hydrolysis kinetics of vicine and convicine and their derivatives during fermentation with L. plantarum DPPMAB24W was investigated. In particular, a specific HPLC method coupled to ESI-MS and MS/MS analysis, including the evaluation procedure of the results, was set up as the analytical approach to monitor the compounds. The degradation of the pyrimidine glycosides in the fermented flour was complete after 48 h of incubation and the aglycone derivatives could not be detected in any of the samples. The toxicity of the fermented faba bean was established through ex-vivo assays on human blood, confirming the experimental findings. Results indicate that mild and cost effective bioprocessing techniques can be applied to detoxify faba bean also for industrial applications.


Assuntos
Barbitúricos/metabolismo , Farinha/análise , Glucosídeos/metabolismo , Lactobacillus plantarum/metabolismo , Pirimidinonas/metabolismo , Uridina/análogos & derivados , Vicia faba/metabolismo , Barbitúricos/toxicidade , Biotransformação , Fermentação , Tecnologia de Alimentos/métodos , Glucosídeos/toxicidade , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Pirimidinonas/toxicidade , Espectrometria de Massas por Ionização por Electrospray , Uridina/metabolismo , Uridina/toxicidade , Vicia faba/toxicidade
9.
J Mass Spectrom ; 51(9): 768-81, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27479706

RESUMO

Hydrophilic interaction liquid chromatography coupled to electrospray ionization-Fourier transform mass spectrometry was employed to study ceramide lipids occurring in mussels of sp. Mytilus galloprovincialis. Lipid extracts from alive mussels and mussels deliberately subjected to specific thermal treatments were analyzed. In particular, single and tandem MS measurements were performed on a hybrid quadrupole-Orbitrap mass spectrometer and then complemented by MS(n) analyses (n = 2, 3) achieved by a linear ion trap mass spectrometer. This approach enabled the characterization of 66 ceramide lipids, encompassing ceramide phosphoethanolamines (CPE), ceramide aminoethylphosphonates (CAEP) and N-monomethylated CAEP. The sphingoid and acyl chains of each ceramide lipid could be distinctly recognized in terms of numbers of carbon atoms and C=C bonds, and indications on the possible location of the latter on the sphingoid chain could be often inferred from fragmentation patterns. The occurrence of several species hydroxylated on the α carbon of the acyl chain was also discovered. On the other hand, the sphingoid chain of ceramide lipids was never found to be involved in oxidation processes, unless forced exposure of the mussel lipid extracts to atmospheric oxygen was performed. CPE(d19:3/16:0) and its hydroxylated form, CPE(d19:3/2-OH-16:0), were found to be the prevailing species among CPE, whereas CAEP(d18:2/16:0), CAEP(d19:3/16:0) and CAEP(d19:3/2-OH-16:0) were the most abundant CAEP. Finally, ceramide lipids showed a remarkably higher stability, compared with glycerophospholipids, in mussels subjected to different thermal treatments. This finding opens interesting perspectives on the role of ceramide-based lipids in the adaptation of aquatic organisms to thermal stresses. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Bivalves/química , Ceramidas/análise , Cromatografia Líquida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Temperatura Baixa , Armazenamento de Alimentos , Análise de Fourier , Interações Hidrofóbicas e Hidrofílicas , Lisofosfolipídeos , Espectrometria de Massas em Tandem/métodos
10.
Curr Neurovasc Res ; 13(2): 147-55, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26903394

RESUMO

The fiber matrix of the surface glycocalyx layer internally coating the endothelial cells and plugging the intercellular clefts is crucial for microvascular wall homeostasis. Disruption of the glycocalyx is found in clinical conditions characterized by microvascular and endothelial dysfunction such as atherosclerosis, diabetes mellitus, chronic renal failure and cerebrovascular disease. Shedding of its components may also occur during oxidative stress and systemic inflammatory states including septis. In this work, we investigate the effects of glycocalyx degradation, either due to enzymatic digestion or to agonist recruitment, on plasma filtration and solute extravasation. We also take into account the possibility of a physiological or pathological increase in blood pressure, as in hypertensive zones such as pre- and post-stenotic blood vessels. Our mathematical model shows that a seriously damaged glycocalyx produces an augmentation of flux of both solvent and solute, thus losing its role of transport barrier and macro-molecular sieve, in agreement with experimental evidence. Similarly, hypertension causes an increase in both volume and solute fluxes, also according to physiological findings. The combination of glycocalyx deterioration and hypertension further raises plasma and solute fluxes, potentially leading in most severe cases to edema and hemorrhage, as in the case of diabetes.


Assuntos
Endotélio Vascular/patologia , Glicocálix/metabolismo , Homeostase , Hipertensão/fisiopatologia , Modelos Biológicos , Animais , Permeabilidade Capilar , Humanos , Hipertensão/sangue , Modelos Teóricos
11.
Electrophoresis ; 37(13): 1823-38, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26860242

RESUMO

The separation efficiency of hydrophilic interaction liquid chromatography and the high resolution/accuracy of electrospray ionization-Fourier transform MS were successfully applied to the detailed characterization of lyso-phosphatidylcholines (LPCs) and lyso-phosphatidylethanolamines (LPEs) contained in the lipid extracts of Mytilus galloprovincialis (Mediterranean mussel). As a result, 57 LPCs, including regio- and positional isomers, and 45 LPEs, including acyl and plasma(e)nyl species, were identified. Four lyso-phosphonocholines were also identified among mussel Lyso-Phospholipids. To the best of our knowledge this represents the first characterization, at a molecular level, ever reported for LPEs in mussels. No significant variation was observed in the composition of both LPCs and LPEs when mussels were refrigerated at +4°C for up to 48 h, i.e. under conditions usually employed for seafood transportation and storage. Treatments mimicking more severe thermal stresses, namely eight day-refrigeration at + 4°C, two week-freezing at -15°C and 6 h-storage at 25°C, resulted in a significant increase in the molar abundance of LPCs and LPEs (expressed with respect to that of their precursors, PCs and PEs, respectively) and was accompanied by the death of all or part of the molluscs. These results were interpreted invoking the generation of lyso-phospholipids, mediated by endogenous phospholipases, as an intermediate process toward the partial replacement of side chains in phospholipids, perhaps functional to a better adaptation of mussels to adverse temperature conditions. Interestingly, the relative abundances of specific compounds belonging to the LPC and LPE classes were found to follow the seasonal variations of sea temperature.


Assuntos
Bivalves/química , Cromatografia Líquida/métodos , Lisofosfolipídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Análise de Fourier
12.
Anal Bioanal Chem ; 405(5): 1641-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23232957

RESUMO

In the dairy industry one of the most common frauds is mixing high-value milk (sheep's and goats') with milk of lower value (cows'). This illegal practice has commercial, ethical, and serious sanitary consequences because consumers can be exposed to hidden allergens contained in the undeclared cows' milk. Here, we investigated the possibility of using matrix-assisted laser-desorption/ionization (MALDI)-time of flight (TOF) mass spectrometry (MS) as a rapid, sensitive, and accurate technique for detection of milk adulteration by analysis of phospholipid profiles. Lipid extracts of pure raw milk, commercial milk, and binary mixtures of cows' and goats' milk and cows' and sheep's milk (the concentrations of each milk varied from 0 % to 50 %) were analyzed with α-cyano-4-chlorocinnamic acid as matrix. The abundance ratio of the ions at m/z 703 and m/z 706 was found to be species-correlated and was used as marker of cows' milk in sheep's and goats' milk. Furthermore, the procedure could potentially be applied to cheese samples, because peaks at m/z 703 and 706 were also found in several commercial cheese samples. This approach proved to be an efficient, rapid, and inexpensive method of detecting milk fraud.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Leite/química , Fosfolipídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Bovinos , Análise de Alimentos/economia , Cabras , Ovinos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/economia , Fatores de Tempo
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