94 research outputs found
Correction: Printable and flexible electronics: from TFTs to bioelectronic devices
Correction for 'Printable and flexible electronics: from TFTs to bioelectronic devices' by M. Magliulo et al., J. Mater. Chem. C, 2015, 3, 12347–12363
About the amplification factors in organic bioelectronic sensors
A systematic comparison between electrochemical and organic bioelectronic sensors reveals a unified rational description for a transistor amplified detection
Electrochemical and X-ray Photoelectron Spectroscopy Surface Characterization of Interchain-Driven Self-Assembled Monolayer (SAM) Reorganization
Herein, we report a combined strategy encompassing electrochemical and X-ray photoelectron
spectroscopy (XPS) experiments to investigate self-assembled monolayer (SAM) conformational
reorganization onto an electrode surface due to the application of an electrical field. In particular,
3-mercaptopriopionic acid SAM (3MPA SAM) modified gold electrodes are activated with a 1-ethyl-3-
(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysulfosuccinimide (NHSS) (EDC-NHSS)
mixture by shortening the activation time, from 2 h to 15/20 min, labelled as Protocol-A, -B and -C,
respectively. This step, later followed by a deactivation process with ethanolamine (EA), plays a key
role in the reaction yields (formation of N-(2-hydroxyethyl)-3-mercaptopropanamide, NMPA) but
also in the conformational rearrangement observed during the application of the electrical field. This
study aims at explaining the high performance (i.e., single-molecule detection at a large electrode
interface) of bioelectronic devices, where the 3MPA-based SAM structure is pivotal in achieving
extremely high sensing performance levels due to its interchain interaction. Cyclic voltammetry (CV)
experiments performed in K4Fe(CN)6:K3Fe(CN)6 for 3MPA SAMs that are activated/deactivated
show similar trends of anodic peak current (IA) over time, mainly related to the presence of interchain
hydrogen bonds, driving the conformational rearrangements (tightening of SAMs structure)
while applying an electrical field. In addition, XPS analysis allows correlation of the deactivation
yield with electrochemical data (conformational rearrangements), identifying the best protocol in
terms of high reaction yield, mainly related to the shorter reaction time, and not triggering any side
reactions. Finally, Protocol-C’s SAM surface coverage, determined by CV in H2SO4 and differential
pulse voltammetry (DPV) in NaOH, was 1.29 * 1013 molecules cm2, being similar to the bioreceptor
surface coverage in single-molecule detection at a large electrode interface
Development of terphenyl-2-methyloxazol-5(4H)-one derivatives as selective reversible MAGL inhibitors
Monoacylglycerol lipase is a serine hydrolase that plays a major role in the degradation of the endocannabinoid neurotransmitter 2-arachidonoylglycerol. A wide number of MAGL inhibitors are reported in literature; however, many of them are characterised by an irreversible mechanism of action and this behavior determines an unwanted chronic MAGL inactivation, which acquires a functional antagonism of the endocannabinoid system. The possible use of reversible MAGL inhibitors has only recently been explored, due to the lack of known compounds possessing efficient reversible inhibitory activities. In this work, we report a new series of terphenyl-2-methyloxazol-5(4H)-one derivatives characterised by a reversible MAGL-inhibition mechanism. Among them, compound 20b showed to be a potent MAGL reversible inhibitor (IC50= 348 nM) with a good MAGL/FAAH selectivity. Furthermore, this compound showed antiproliferative activities against two different cancer cell lines that overexpress MAGL
Surface Plasmon Resonance Assay for Label-Free and Selective Detection of Xylella Fastidiosa
Xylella fastidiosa is among the most dangerous plant bacteria worldwide causing
a variety of diseases, with huge economic impact on agriculture and environment.
A surveillance tool, ensuring the highest possible sensitivity enabling the
early detection of X. fastidiosa outbreaks, would be of paramount importance. So
far, a variety of plant pathogen biomarkers are studied by means of surface
plasmon resonance (SPR). Herein, multiparameter SPR (MP-SPR) is used
for the first time to develop a reliable and label-free detection method for X.
fastidiosa. The real-time monitoring of the bioaffinity reactions is provided as
well. Selectivity is guaranteed by biofunctionalizing the gold transducing interface
with polyclonal antibodies for X. fastidiosa and it is assessed by means of a
negative control experiment involving the nonbinding Paraburkholderia phytofirmans
bacterium strain PsJN. Limit of detection of 105 CFU mL 1 is achieved by
transducing the direct interaction between the bacterium and its affinity antibody.
Moreover, the binding affinity between polyclonal antibodies and X. fastidiosa
bacteria is also evaluated, returning an affinity constant of 3.5   107m 1,
comparable with those given in the literature for bacteria detection against
affinity antibodies
Organic bioelectronics probing conformational changes in surface confined proteins
The study of proteins confined on a surface has attracted a great deal of attention due to its relevance in the development of bio-systems for laboratory and clinical settings. In this respect, organic bio-electronic platforms can be used as tools to achieve a deeper understanding of the processes involving protein interfaces. In this work, biotin-binding proteins have been integrated in two different organic thin-film transistor (TFT) configurations to separately address the changes occurring in the protein-ligand complex morphology and dipole moment. This has been achieved by decoupling the output current change upon binding, taken as the transducing signal, into its component figures of merit. In particular, the threshold voltage is related to the protein dipole moment, while the field-effect mobility is associated with conformational changes occurring in the proteins of the layer when ligand binding occurs. Molecular Dynamics simulations on the whole avidin tetramer in presence and absence of ligands were carried out, to evaluate how the tight interactions with the ligand affect the protein dipole moment and the conformation of the loops surrounding the binding pocket. These simulations allow assembling a rather complete picture of the studied interaction processes and support the interpretation of the experimental results
Guidelines for the use and interpretation of diagnostic methods in adult food allergy
Food allergy has an increasing prevalence in the general population and in Italy concerns 8 % of people with allergies. The spectrum of its clinical manifestations ranges from mild symptoms up to potentially fatal anaphylactic shock. A number of patients can be diagnosed easily by the use of first- and second-level procedures (history, skin tests and allergen specific IgE). Patients with complex presentation, such as multiple sensitizations and pollen-food syndromes, frequently require a third-level approach including molecular diagnostics, which enables the design of a component-resolved sensitization profile for each patient. The use of such techniques involves specialists' and experts' skills on the issue to appropriately meet the diagnostic and therapeutic needs of patients. Particularly, educational programs for allergists on the use and interpretation of molecular diagnostics are needed
Correction: Printed, cost-effective and stable poly(3-hexylthiophene) electrolyte-gated field-effect transistors
Correction for 'Printed, cost-effective and stable poly(3-hexylthiophene) electrolyte-gated field-effect transistors' by Davide Blasi et al., J. Mater. Chem. C, 2020, DOI: 10.1039/d0tc03342a
Short course palliative radiotherapy in advanced solid tumors: a pooled analysis (the SHARON project)
Previous trials showed the tolerability and efficacy of a palliative radiotherapy (RT) regimen (SHARON) based on the 4 fractions delivered in 2 days in different oncological settings. In order to identify possible predictors of symptomatic response, the purpose of this study is to perform a pooled analysis of previous trials. We analyzed the impact on symptomatic response of the following parameters: tumor site, histological type, performance status (ECOG), dominant symptom, and RT dose using the Chi-square test and Fisher's exact test. One-hundred-eighty patients were analyzed. Median RT dose was 20 Gy (range: 14-20 Gy). The overall response rate was 88.8% (95% CI 83.3-92.7%) while pre- and post-treatment mean VAS was 5.3 (+/- 7.7) and 2.2 (+/- 2.2), respectively (p < 0.001). The overall response rate of pain, dyspnea, bleeding, dysphagia, and other symptoms was 86.2%, 90.9%, 100%, 87.5%, and 100%, respectively. Comparing the symptomatic effect based on the analyzed parameters no significant differences were recorded. However, patients with locally advanced disease showed a higher rate of symptomatic responses than metastatic ones (97.3% vs 83.0%; p = 0.021). Finally, the complete pain response rate was more than double in patients with mild to moderate (VAS: 4-7) compared to those with severe (VAS > 7) pain (36.0% vs 14.3%; p = 0.028). This pooled analysis showed high efficacy of the SHARON regimen in the relief of several cancer-related symptoms. The markedly and significantly higher complete pain response rate, in patients with mild-moderate pain, suggests early referral to palliative RT for patients with cancer-related pain
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