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Pesticides are largely used at worldwide level to improve food production, fulfilling the needs of the global population which is increasing year by year. Although pesticides are beneficial for crop production, their extensive use has serious consequences for the pollution of the produced food as well as for soil and groundwaters. Indeed, it is reported that 50% of sprayed pesticides reach different destinations other than their target species, including soil, surface waters, and groundwaters. For this reason, we developed a flower-like origami paper-based device for pesticides detection in aerosol phase for precision agriculture. In detail, the paper-based electrochemical platform detects paraoxon, 2,4-dichlorophenoxyacetic acid, and glyphosate at ppb levels by measuring their inhibitory activity towards three different enzymes namely butyrylcholinesterase, alkaline phosphatase, and peroxidase enzyme, respectively. This integrated electrochemical device is composed of three office paper-based screen-printed electrodes and filter paper-based pads loaded with enzymes and enzymatic substrates. The pesticide detection is carried out by measuring through chronoamperometric technique the initial and residual enzymatic activity by using a smartphone-assisted potentiostat and evaluating the percentage of inhibition, proportional to the amount of aerosolized pesticides. This paper-based device was able to detect the three classes of pesticides in aerosol phase with limits of detection equal to 30 ppb, 10 ppb, and 2 ppb, respectively for 2,4-D, glyphosate, and paraoxon.

The characterization of an economic and ease-to-use carbon paste acetylcholinesterase (AChE) based biosensor to determine the concentration of pesticides Paraoxon and Dichlorvos is discussed. AChE hydrolyses acetylthiocholine (ATCh) in thiocoline (TC) and acetic acid (AA). When AChE is immobilized into a paste carbon working electrode kept at +410 mV vs. Ag/AgCl electrode, the enzyme reaction rate using acetylthiocholine chloride (ATCl) as substrate is monitored as a current intensity. Because Paraoxon and Dichlorvos inhibit the AChE reaction, the decrease of the current intensity, at fixed ATCl concentration, is a measure of their concentration. Linear calibration curves for Paraoxon and Dichlorvos determination have been obtained. The detection limits resulted to be 0.86 ppb and 4.2 ppb for Paraoxon and Dichlorvos, respectively, while the extension of the linear range was up 23 ppb for the former pesticide and up to 33 ppb for the latter. Because the inhibited enzyme can be reactivated when immediately treated with an oxime, the biosensor reactivation has been studied when 1,1'-trimethylene bis 4-formylpyridinium bromide dioxime (TMB-4) and pyridine 2-aldoxime methiodide (2-PAM) were used. TMB-4 resulted more effective. The comparison with the behavior of similar AChE based biosensors is also presented.

Current studies are investigating new E-cadherin gene (CDH1) mutations that may be responsible for diffuse gastric cancer susceptibility. Recently, a novel CDH1 germline variant presenting a G/A nucleotide change at cDNA position 2494 has been found in Japanese patients with familial diffuse gastric cancer. The consequent amino acid variation (Val/Met) may alter the binding activity to beta-catenin and the adhesive function of the E-cadherin protein. We have investigated its frequency in Italian cases of sporadic diffuse gastric cancer a well as in healthy controls. Peripheral blood samples were collected from consecutive patients with sporadic, diffuse gastric cancer and from healthy controls in the District of Urbino, Marche Region, Central Italy. After DNA extraction, standard techniques for molecular analyses were used to investigate the 2494 G/A germline nucleotide change in CDH1 cDNA. None of the 48 patients and 48 controls showed the G/A 2494 nucleotide change. Assuming a binomial distribution of the mutation among individuals and the absence of mutations in the 48 patients, the 95% upper bound for the underlying mutation frequency was 7.4%. The novel CDH1 nucleotide change is uncommon in Italian patients with sporadic diffuse gastric cancer. Given these results, further analyses in large population-based studies are not advisable

To assess the value of Computed Tomography (CT) in the diagnosis and in morphologic characterization of metastatic melanoma.The data of total body CT of 124 consecutive patients with melanoma having a Breslow index 1 mm or a positive sentinel lymph node have been retrospectively reviewed.The CT scan showed loco-regional and/or distant metastases in 36 patients (39%). Ten of these (28%) had metastases only to lymph nodes, whereas 26 patients (72%) had multiple metastases. Nodal, pulmonary, brain, subcutaneous, hepatic, adrenal, bone, gastrointestinal, breast and abdominal wall metastases were detected in 80.6%, 47.2%, 25%, 25%, 16.7%, 13.9%, 11.1%, 5.6%, 5.6% and 2.8% of the patients respectively. All the patients with metastases also had a positive sentinel lymph nodes and/or symptoms of metastatic disease.CT fails to reveal any characteristic feature of metastatic melanoma, but it is of value in the diagnosis of loco-regional and distant metastases in III stage disease.

BACKGROUND: The use of robotic technologies in pediatric rehabilitation has seen a large increase, but with a lack of a comprehensive framework about their effectiveness. OBJECTIVE: An Italian Consensus Conference has been promoted to develop recommendations on these technologies: definitions and classification criteria of devices, indications and limits of their use in neurological diseases, theoretical models, ethical and legal implications. In this paper, we present the results for the pediatric age. METHODS: A systematic search on Cochrane Library, PEDro and PubMed was performed. Papers published up to March 1st, 2020, in English, were included and analyzed using the methodology of the Centre for Evidence-Based Medicine in Oxford, AMSTAR2 and PEDro scales for systematic reviews and RCT, respectively. RESULTS: Some positives aspects emerged in the area of gait: an increased number of children reaching the stance, an improvement in walking distance, speed and endurance. Critical aspects include the heterogeneity of the studied cases, measurements and training protocols. CONCLUSION: Many studies demonstrate the benefits of robotic training in developmental age. However, it is necessary to increase the number of trials to achieve greater homogeneity between protocols and to confirm the effectiveness of pediatric robotic rehabilitation.

Paper-based devices are always more gaining a relevant position in the field of sensors. The continuous demand for affordable, simple, sustainable, and portable devices, is making paper as the ideal basis towards the realization of analytical tools for the easy self-testing. In this work, we demonstrate, for the first time, the development of a disposable paper-based printed electroanalytical strip for reliable, rapid, and high-throughput detection of glutathione in blood. The detection is based on the thiol-disulfide exchange reaction, which produces a detectable compound easily oxidizable at a Prussian Blue/carbon black nanocomposite involving a favorable low-interference overpotential. This nanocomposite is mixed within a carbon-based conductive ink and successively screen-printed onto a wax-patterned filter paper. The employment of paper provides a reagent-free device, as a consequence of the reagents pre-loading within the testing area. After the experimental conditions have been optimized, glutathione has been detected up to 10 mM, with a detection limit of 60 μM, and a sensitivity of (0.102 ± 0.005) μA/mM. This sensor showed satisfactory repeatability (relative standard deviation equal to 10%, for detection of glutathione 1 mM), especially by considering the hand-made manufacturing process. The “real-world” applicability of this strip has been evaluated by quantifying blood glutathione at physiological levels and by recovery studies achieving satisfactory values.

Nowadays, environmentally friendly synthesis pathways for preserving the environment and minimizing waste are strongly required. Herein, we propose filter paper as a convenient scaffold for chemical reactions. To demonstrate this novel approach, Prussian Blue Nanoparticles (PBNPs) were synthesized on filter paper by utilizing few μL of its precursors without external inputs, i.e. pH, voltage, reducing agents, and without producing waste as well. The functional paper, named “Paper Blue”, is successfully applied in the sensing field, exploiting the reduction of hydrogen peroxide at low applied potential. The eco-designed “Paper Blue” was combined with wax- and screen-printing to manufacture a reagentless electrochemical point-of-care device for diabetes self-monitoring, by using glucose oxidase as the biological recognition element. Blood glucose was linearly detected for a wide concentration range up to 25 mM (450 mg/dL), demonstrating its suitability for management of diabetes and glucose-related diseases. The Paper Blue-based biosensor demonstrated a correlation coefficient of 0.987 with commercial glucose strips (Bayer Contour XT). The achieved results demonstrated the effectiveness of this approach, which is also extendible to other (bio)systems to be applied in catalysis, remediation, and diagnostics.

Altres ajuts: the ICN2 is funded by the CERCA Programme/Generalitat de Catalunya. The development of paper-based electroanalytical strips as powerful diagnostic tools has gained a lot of attention within the sensor community. In particular, the detection of nucleic acids in complex matrices represents a trending topic, especially when focused toward the development of emerging technologies, such as liquid biopsy. DNA-based biosensors have been largely applied in this direction, and currently, there are two main approaches based on target/probe hybridization reported in the literature, namely Signal ON and Signal OFF. In this technical note, the two approaches are evaluated in combination with paper-based electrodes, using a single strand DNA relative to H1047R (A3140G) missense mutation in exon 20 in breast cancer as the model target. A detailed comparison among the analytical performances, detection protocol, and cost associated with the two systems is provided, highlighting the advantages and drawbacks depending on the application. The present work is aimed to a wide audience, particularly for those in the field of point-of-care, and it is intended to provide the know-how to manage with the design and development stages, and to optimize the platform for the sensing of nucleic acids using a paper-based detection method.

Biosensor development exploiting various transduction principles is characterized by a strong competition to reach high detectability, portability and robustness. Nevertheless, a literature-based comparison is not possible, as different conditions are employed in each paper. Herein, we aim at evaluating which measurement, photons or electrons, yields better biosensor performance. Upon outlining an update in recent achievements to boost analytical performance, amperometry and chemiluminescence (CL)-based biosensors are directly compared employing the same biospecific reagents and analytical formats. Horseradish peroxidase (HRP) and hydrogen peroxide concentrations were directly measured, while glucose and mouse IgG were detected employing an enzyme paper-based biosensor and an immunosensor, respectively. Detectability was down to picomoles of hydrogen peroxide (4 pmol for CL and 210 pmol for amperometry) and zeptomoles of HRP (45 zmol for CL and 20 zmol for amperometry); IgG was detected down to 12 fM (CL) and 120 fM (amperometry), while glucose down to 17 μM (CL) and 40 μM (amperometry). Results showed that amperometric and CL biosensors offered similar detectability and analytical performance, with some peculiarities that suggest complementary application fields. As they generally provided slightly higher detectability and wider dynamic ranges, CL-based biosensors appear more suitable for point-of-care testing of clinical biomarkers, where detectability is crucial. Nevertheless, as high detectability in CL biosensors usually requires longer acquisition times, their rapidity will allocate electrochemical biosensors in real-time monitoring and wearable biosensors. The analytical challenge demonstrated that these biosensors have competitive and similar performance, and between photons and electrons the competition is still open.

In the last decades, there is a growing search for analytical strategies to ensure clinical analysis without the need of laboratory set-up and skilled personnel. Indeed, user-friendly and low-cost devices are highly valued in the era of sustainability for their capability to be applied in low-resource contexts, such as developing countries. To address this issue, herein we report a 96-well paper-based and laboratory setup-free optical platform for the detection of butyrylcholinesterase enzyme (BChE) activity in human serum. We used chromatographic paper to realize a novel analytical tool exploiting its porous structure for reagentless synthesize Prussian Blue Nanoparticles (the sensing element), as well to load all the reagents required for the measurement. The principle of BChE activity detection relies on the reaction between the enzymatic product thiocholine and Prussian Blue, giving the Prussian White with subsequently Prussian Blue's fading, detected by a common office scanner supported by ImageJ software. Using this novel paper-based optical platform, BChE activity was linearly detected in the 2–15 U/mL range with a detection limit down to 0.8 U/mL. The accuracy was successfully demonstrated by recovery study with spiked serum and by comparing the data with the gold standard method.

Herein, we report the synthesis of several magnetic carbon structures starting from spheres (CSs) to more elongated structures to get tubes and fibers by customizing chemical vapour deposition parameters. These CSs-based products, ranging from nano-to micro-size, were investigated by morphological point of view using scanning electron microscopy, energy dispersive x-ray spectroscopy, and Raman spectroscopy. These carbon structures were combined with screen-printed electrodes highlighting their electrochemical effectiveness towards the detection of several species, i.e. ferricyanide, ascorbic acid, dopamine, cysteine, serotonin, and NADH. The presence of iron nuclei within the carbonaceous lattices, besides having improved the electrochemical performances at the printed electrodes, might confer these CSs-based structures a future application in the field of remediation/sensing. Herein, some preliminary applications were provided showing that these materials can be easily employed to collect species and, successively, coupled with printed electrochemical sensors.