39 research outputs found

    Cavitation bubble wall pressure measurement by an electromagnetic surface wave enhanced pump-probe configuration

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    We report on the measurement of the pressure associated with a shock wave within a very thin layer (100 nm) in proximity of a boundarysurface. In the experiments, the shock wave was emitted by a cavitation bubble generated by a pulsed pump laser in water. We developed apump-probe setup based on the detection of the light scattered at the surface of a one-dimensional photonic crystal, which was purposelydesigned to sustain a surface electromagnetic wave in the visible range and to enhance the optical response. In order to better understand thephenomenon, we implemented numerical simulations to describe the light scattering intensity distributions through a modified Rayleigh’smethod. We report, with a LoD of about 0.1 MPa, the measurements of the pressure at a surface in the presence of a laser-induced cavitationbubble generated at different distances from the surface and for different pulse energies

    Perspectives on cavitation enhanced endothelial layer permeability

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    Traditional drug delivery systems, where pharmaceutical agents are conveyed to the target tissue through the blood circulation, suffer of poor therapeutic efficiency and limited selectivity largely due to the low permeability of the highly specialised biological interface represented by the endothelial layer. Examples concern cancer therapeutics or degenerative disorders where drug delivery is inhibited by the blood-brain barrier (BBB). Microbubbles injected into the bloodstream undergo volume oscillations under localised ultrasound irradiation and possibly collapse near the site of interest, with no effect on the rest of the endothelium. The resulting mechanical action induces a transient increase of the inter-cellular spaces and facilitates drug extravasation. This approach, already pursed in in vivo animal models, is extremely expensive and time-consuming. On the other hand in vitro studies using different kinds of microfluidic networks are firmly established in the pharmaceutical industry for drug delivery testing. The combination of the in vitro approach with ultrasound used to control microbubbles oscillations is expected to provide crucial information for developing cavitation enhanced drug delivery protocols and for screening the properties of the biological interface in presence of healthy or diseased tissues. Purpose of the present review is providing the state of the art in this rapidly growing field where cavitation is exploited as a viable technology to transiently modify the permeability of the biological interface. After describing current in vivo studies, particular emphasis will be placed on illustrating characteristics of micro-devices, biological functionalisation, properties of the artificial endothelium and ultrasound irradiation techniques

    Expression profile of HERVs and inflammatory mediators detected in nasal mucosa as a predictive biomarker of COVID-19 severity

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    IntroductionOur research group and others demonstrated the implication of the human endogenous retroviruses (HERVs) in SARS-CoV-2 infection and their association with disease progression, suggesting HERVs as contributing factors in COVID-19 immunopathology. To identify early predictive biomarkers of the COVID-19 severity, we analyzed the expression of HERVs and inflammatory mediators in SARS-CoV-2-positive and -negative nasopharyngeal/oropharyngeal swabs with respect to biochemical parameters and clinical outcome.MethodsResiduals of swab samples (20 SARS-CoV-2-negative and 43 SARS-CoV-2-positive) were collected during the first wave of the pandemic and expression levels of HERVs and inflammatory mediators were analyzed by qRT-Real time PCR.ResultsThe results obtained show that infection with SARS-CoV-2 resulted in a general increase in the expression of HERVs and mediators of the immune response. In particular, SARS-CoV-2 infection is associated with increased expression of HERV-K and HERV-W, IL-1β, IL-6, IL-17, TNF-α, MCP-1, INF-γ, TLR-3, and TLR-7, while lower levels of IL-10, IFN-α, IFN-β, and TLR-4 were found in individuals who underwent hospitalization. Moreover, higher expression of HERV-W, IL-1β, IL-6, IFN-α, and IFN-β reflected the respiratory outcome of patients during hospitalization. Interestingly, a machine learning model was able to classify hospitalized vs not hospitalized patients with good accuracy based on the expression levels of HERV-K, HERV-W, IL-6, TNF-a, TLR-3, TLR-7, and the N gene of SARS-CoV-2. These latest biomarkers also correlated with parameters of coagulation and inflammation.DiscussionOverall, the present results suggest HERVs as contributing elements in COVID-19 and early genomic biomarkers to predict COVID-19 severity and disease outcome

    Multicentre harmonisation of a six-colour flow cytometry panel for naïve/memory T cell immunomonitoring

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    Background. Personalised medicine in oncology needs standardised immunological assays. Flow cytometry (FCM) methods represent an essential tool for immunomonitoring, and their harmonisation is crucial to obtain comparable data in multicentre clinical trials. The objective of this study was to design a harmonisation workflow able to address the most effective issues contributing to intra- and interoperator variabilities in a multicentre project. Methods. The Italian National Institute of Health (Istituto Superiore di Sanita, ISS) managed a multiparametric flow cytometric panel harmonisation among thirteen operators belonging to five clinical and research centres of Lazio region (Italy). The panel was based on a backbone mixture of dried antibodies (anti-CD3, anti-CD4, anti-CD8, anti-CD45RA, and anti-CCR7) to detect naive/memory T cells, recognised as potential prognostic/predictive immunological biomarkers in cancer immunotherapies. The coordinating centre distributed frozen peripheral blood mononuclear cells (PBMCs) and fresh whole blood (WB) samples from healthy donors, reagents, and Standard Operating Procedures (SOPs) to participants who performed experiments by their own equipment, in order to mimic a real-life scenario. Operators returned raw and locally analysed data to ISS for central analysis and statistical elaboration. Results. Harmonised and reproducible results were obtained by sharing experimental set-up and procedures along with centralising data analysis, leading to a reduction of cross-centre variability for naive/memory subset frequencies particularly in the whole blood setting. Conclusion. Our experimental and analytical working process proved to be suitable for the harmonisation of FCM assays in a multicentre setting, where high-quality data are required to evaluate potential immunological markers, which may contribute to select better therapeutic options

    Physiological parameters for Prognosis in Abdominal Sepsis (PIPAS) Study : a WSES observational study

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    BackgroundTiming and adequacy of peritoneal source control are the most important pillars in the management of patients with acute peritonitis. Therefore, early prognostic evaluation of acute peritonitis is paramount to assess the severity and establish a prompt and appropriate treatment. The objectives of this study were to identify clinical and laboratory predictors for in-hospital mortality in patients with acute peritonitis and to develop a warning score system, based on easily recognizable and assessable variables, globally accepted.MethodsThis worldwide multicentre observational study included 153 surgical departments across 56 countries over a 4-month study period between February 1, 2018, and May 31, 2018.ResultsA total of 3137 patients were included, with 1815 (57.9%) men and 1322 (42.1%) women, with a median age of 47years (interquartile range [IQR] 28-66). The overall in-hospital mortality rate was 8.9%, with a median length of stay of 6days (IQR 4-10). Using multivariable logistic regression, independent variables associated with in-hospital mortality were identified: age > 80years, malignancy, severe cardiovascular disease, severe chronic kidney disease, respiratory rate >= 22 breaths/min, systolic blood pressure 4mmol/l. These variables were used to create the PIPAS Severity Score, a bedside early warning score for patients with acute peritonitis. The overall mortality was 2.9% for patients who had scores of 0-1, 22.7% for those who had scores of 2-3, 46.8% for those who had scores of 4-5, and 86.7% for those who have scores of 7-8.ConclusionsThe simple PIPAS Severity Score can be used on a global level and can help clinicians to identify patients at high risk for treatment failure and mortality.Peer reviewe

    Global validation of the WSES Sepsis Severity Score for patients with complicated intra-abdominal infections : a prospective multicentre study (WISS Study)

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    Background: To validate a new practical Sepsis Severity Score for patients with complicated intra-abdominal infections (cIAIs) including the clinical conditions at the admission (severe sepsis/septic shock), the origin of the cIAIs, the delay in source control, the setting of acquisition and any risk factors such as age and immunosuppression. Methods: The WISS study (WSES cIAIs Score Study) is a multicenter observational study underwent in 132 medical institutions worldwide during a four-month study period (October 2014-February 2015). Four thousand five hundred thirty-three patients with a mean age of 51.2 years (range 18-99) were enrolled in the WISS study. Results: Univariate analysis has shown that all factors that were previously included in the WSES Sepsis Severity Score were highly statistically significant between those who died and those who survived (p <0.0001). The multivariate logistic regression model was highly significant (p <0.0001, R-2 = 0.54) and showed that all these factors were independent in predicting mortality of sepsis. Receiver Operator Curve has shown that the WSES Severity Sepsis Score had an excellent prediction for mortality. A score above 5.5 was the best predictor of mortality having a sensitivity of 89.2 %, a specificity of 83.5 % and a positive likelihood ratio of 5.4. Conclusions: WSES Sepsis Severity Score for patients with complicated Intra-abdominal infections can be used on global level. It has shown high sensitivity, specificity, and likelihood ratio that may help us in making clinical decisions.Peer reviewe

    SEPARATION OF DANSYLAMINO ACID ENANTIOMERS BY THIN-LAYER CHROMATOGRAPHY

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    A simple thin-layer chromatographic method for the separation of D- and L-dansylamino acids using a new resolving agent is described. The enantiomeric resolution of racemates was accomplished on reversed-phase plates pre-treated with a poly-L-phenylalaninamide - copper(II) complex using water- acetonitrile mixtures as eluent under isocratic conditions. The polymeric ligand was easily prepared by reaction of the optically active amide with ethylene glycol diglycidyl ether at room temperature. The method is rapid and sensitive, and was successfully employed to resolve various dansylamino acids

    Separation of Flavanone-7- O-

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    CEC enantioseparations of carboxylic acids on silica-based monoliths modified with ergot alkaloid derivative

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    The enantioseparation of carboxylic acids, including amino acid dansyl-derivatives, 2-arylpropionic acids and 2-aryloxypropionic acids, was tested by CEC on a porous silica sol-gel monolithic column that was prepared by polycondensation of tetramethoxysilane in acidic conditions and post-gelation heat treatment (120 degrees C for 3 h) in the presence of urea, and successively, by anchoring to the silica (+)-1-allyl-(5R,8S,10R)-terguride as the chiral selector. The bimodal structure of the sorbent showed through pores with a median value of 1.39 mu m and a mesopore size distribution ranging between 6 and 12 nm (average pore size of 9.9 nm). To attain optimum separation conditions, the influence of the pH and the concentration of the buffer solution in the mobile phase on resolution were investigated. The monolithic column showed: (i) for the compounds studied resolution values two or three times higher in comparison with previously developed separation systems where the same chiral selector was used. For example, on the monolithic column Dns-serine enantiomers were much better separated (8 min with a selectivity factor of 1.34) than by HPLC (20 min, alpha = 1.17); (ii) high chemical and mechanical stability as demonstrated by the use of such column for hundreds of analysis along about 1 year without significant variations of the resolution and the retention parameters
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