12 research outputs found
Electrochemical sensing platform based on carbon dots for the simultaneous determination of theophylline and caffeine in tea
A simple and selective method for the determination of caffeine (CAF) and theophylline (THEO) has been developed for a glassy carbon electrode (GCE) modified with a composite including carbon dots (CDs) and chitosan (CS). To our knowledge, there are no previous studies that analyze a CDs-modified GCE for the presence of CAF and THEO. The electrochemical behavior of a GCE modified with a CDs-CS composite was studied in acidic medium by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Considering the sensor analytical parameters, the same linear
concentrations range was found for CAF and THEO ranging from 1 105 to 5 103 mol L1 with the same detection limit (LOD) of 1 106 mol L1. The reproducibility and repeatability data were satisfactory in terms of RSD%. Moreover, the storage stability was evaluated, evidencing good results whatever the experimental conditions used. The developed sensor was applied for the simultaneous determination of CAF and THEO in tea and drug, and results were compared with those obtained with HPLC-ESI-MS in SIR mode as an independent method optimized on purpose. The electrochemical sensor presents the undoubled advantages in terms of cheapness, portability, and ease of use, since it does not require skilled personnel
The rapid spread of SARS-COV-2 Omicron variant in Italy reflected early through wastewater surveillance
The SARS-CoV-2 Omicron variant emerged in South Africa in November 2021, and has later been identified worldwide, raising serious concerns. A real-time RT-PCR assay was designed for the rapid screening of the Omicron variant, targeting characteristic mutations of the spike gene. The assay was used to test 737 sewage samples collected throughout Italy (19/21 Regions) between 11 November and 25 December 2021, with the aim of assessing the spread of the Omicron variant in the country. Positive samples were also tested with a real-time RT-PCR developed by the European Commission, Joint Research Centre (JRC), and through nested RT-PCR followed by Sanger sequencing. Overall, 115 samples tested positive for Omicron SARS-CoV-2 variant. The first occurrence was detected on 7 December, in Veneto, North Italy. Later on, the variant spread extremely fast in three weeks, with prevalence of positive wastewater samples rising from 1.0% (1/104 samples) in the week 5-11 December, to 17.5% (25/143 samples) in the week 12-18, to 65.9% (89/135 samples) in the week 19-25, in line with the increase in cases of infection with the Omicron variant observed during December in Italy. Similarly, the number of Regions/Autonomous Provinces in which the variant was detected increased from one in the first week, to 11 in the second, and to 17 in the last one. The presence of the Omicron variant was confirmed by the JRC real-time RT-PCR in 79.1% (91/115) of the positive samples, and by Sanger sequencing in 66% (64/97) of PCR amplicons. In conclusion, we designed an RT-qPCR assay capable to detect the Omicron variant, which can be successfully used for the purpose of wastewater-based epidemiology. We also described the history of the introduction and diffusion of the Omicron variant in the Italian population and territory, confirming the effectiveness of sewage monitoring as a powerful surveillance tool
Ultralight vector dark matter search using data from the KAGRA O3GK run
Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM
Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo
Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
Outcome after chimeric antigen receptor (CAR) T-cell therapy failure in large B-cell lymphomas
This study retrospectively evaluated the outcome of salvage therapy in 51 patients who failed axicabtagene ciloleucel or tisagenlecleucel for relapsed/refractory large B-cell lymphomas. Of these patients, 22 (43%) were enrolled in clinical trials (glofitamab or loncastuximab tesirine + ibrutinib), whereas 29 received standard therapies (lenalidomide [Len], checkpoint inhibitors [CPIs], ibrutinib [I], chemoimmunotherapy and radiotherapy) or supportive care. Overall, 26 of 39 (67%) treated patients received a treatment based on immunotherapy (glofitamab, CPI, Len) that was mainly represented by bispecific antibody (n = 18). In this subgroup, plasma samples were collected and analysed for circulating tumour DNA (ctDNA) using cancer-personalized profiling by deep sequencing (CAPP-seq). The study found that patients with high ctDNA had poor outcomes. At a median follow-up of 11.7 months, the estimated 12-month overall survival (OS) was 35%. Factors adversely affecting the prognosis in the multivariable model were the absence of response to CAR T-cell therapy (HR: 3.08; p = 0.0109) and a diagnosis other than PMBCL and t-FL (HR: 4.54; p = 0.0069). The outcome of patients failing CAR T cells is poor and requires further investigation
Chemotherapy after PD-1 inhibitors in relapsed/refractory Hodgkin lymphoma: Outcomes and clonal evolution dynamics
Checkpoint inhibitors (CPIs) are routinely employed in relapsed/refractory classical Hodgkin lymphoma. Nonetheless, persistent long-term responses are uncommon, and one-third of patients are refractory. Several reports have suggested that treatment with CPIs may re-sensitize patients to chemotherapy, however there is no consensus on the optimal chemotherapy regimen and subsequent consolidation strategy. In this retrospective study we analysed the response to rechallenge with chemotherapy after CPI failure. Furthermore, we exploratively characterized the clonal evolution profile of a small sample of patients (n = 5) by employing the CALDER approach. Among the 28 patients included in the study, 17 (71%) were primary refractory and 26 (92%) were refractory to the last chemotherapy prior to CPIs. Following rechallenge with chemotherapy, response was recorded in 23 (82%) patients experiencing complete remission and 3 (11%) patients experiencing partial remission. The tumour evolution of the patients inferred by CALDER seemingly occurred prior to the first cycle of therapy and was characterized either by linear or branching evolution patterns. Twenty-five patients proceeded to allogeneic stem cell transplantation. At a median follow-up of 21 months, median PFS and OS were not reached. In conclusion, patients who fail CPIs can be effectively rescued by salvage chemotherapy and bridged to allo-SCT/auto-SCT
Tracking the Spread of the BA.2.86 Lineage in Italy Through Wastewater Analysis
: The emergence of new SARS-CoV-2 variants poses challenges to global surveillance efforts, necessitating swift actions in their detection, evaluation, and management. Among the most recent variants, Omicron BA.2.86 and its sub-lineages have gained attention due to their potential immune evasion properties. This study describes the development of a digital PCR assay for the rapid detection of BA.2.86 and its descendant lineages, in wastewater samples. By using this assay, we analyzed wastewater samples collected in Italy from September 2023 to January 2024. Our analysis revealed the presence of BA.2.86 lineages already in October 2023 with a minimal detection rate of 2% which then rapidly increased, becoming dominant by January 2024, accounting for a prevalence of 62%. The findings emphasize the significance of wastewater-based surveillance in tracking emerging variants and underscore the efficacy of targeted digital PCR assays for environmental monitoring