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We explore and demonstrate the extension of the synapse-mimicking properties of memristive devices to a dysfunctional synapse as it occurs in the Alzheimer's disease (AD) pathology. The ability of memristive devices to reproduce synapse properties such as LTP, LTD, and STDP has been already widely demonstrated, and moreover, they were used for developing artificial neuron networks (perceptrons) able to simulate the information transmission in a cell network. However, a major progress would be to extend the common sense of neuromorphic device even to the case of dysfunction of natural synapses. Can memristors efficiently simulate them? We provide here evidences of the ability of emulating the dysfunctional synaptic behavior typical of the AD pathology with organic memristive devices considering the effect of the disease not only on a single synapse but also in the case of a neural network, composed by numerous synapses.
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Potenciação de Longa Duração/fisiologia , Modelos Neurológicos , Doenças Neurodegenerativas/fisiopatologia , Sinapses/fisiologia , Algoritmos , Encéfalo/fisiopatologia , HumanosRESUMO
Additive manufacturing (AM), or 3D printing processes, is introducing new possibilities in electronic, biomedical, sensor-designing, and wearable technologies. In this context, the present work focuses on the development of flexible 3D-printed polyethylene glycol diacrylate (PEGDA)- sulfonated polyaniline (PANIs) electrically conductive hydrogels (ECHs) for pH-monitoring applications. PEGDA platforms are 3D printed by a stereolithography (SLA) approach. Here, we report the successful realization of PEGDA-PANIs electroconductive hydrogel (ECH) composites produced by an in situ chemical oxidative co-polymerization of aniline (ANI) and aniline 2-sulfonic acid (ANIs) monomers at a 1:1 equimolar ratio in acidic medium. The morphological and functional properties of PEGDA-PANIs are compared to those of PEGDA-PANI composites by coupling SEM, swelling degree, I-V, and electro-chemo-mechanical analyses. The differences are discussed as a function of morphological, structural, and charge transfer/transport properties of the respective PANIs and PANI filler. Our investigation showed that the electrochemical activity of PANIs allows for the exploitation of the PEGDA-PANIs composite as an electrode material for pH monitoring in a linear range compatible with that of most biofluids. This feature, combined with the superior electromechanical behavior, swelling capacity, and water retention properties, makes PEGDA-PANIs hydrogel a promising active material for developing advanced biomedical, soft tissue, and biocompatible electronic applications.
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In recent years, studies concerning Organic Bioelectronics have had a constant growth due to the interest in disciplines such as medicine, biology and food safety in connecting the digital world with the biological one. Specific interests can be found in organic neuromorphic devices and organic transistor sensors, which are rapidly growing due to their low cost, high sensitivity and biocompatibility. This trend is evident in the literature produced in Italy, which is full of breakthrough papers concerning organic transistors-based sensors and organic neuromorphic devices. Therefore, this review focuses on analyzing the Italian production in this field, its trend and possible future evolutions.
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BACKGROUND: No data are available on the presence and content of Coenzyme Q10 (CoQ10) in human follicular fluid and its role. OBJECTIVE: To assess the presence and concentration of CoQ10 in human follicular fluid in relation to oocyte fertilization. METHODS: CQ10 content was measured in follicular fluid obtained from 20 infertile women undergoing ovarian stimulation program for in vitro fertilization. CoQ10 levels were assayed by high-performance liquid chromatography system and normalized for follicular cholesterol and protein levels. Oocyte morphology and embryo grading were assessed. RESULTS: CoQ10/Protein levels resulted significantly in mature versus dysmorphic oocytes. Similarly, CoQ10/Cholesterol was significantly higher in grading I-II versus grading III-IV embryos. CONCLUSIONS: This study is the first demonstration of the presence of CoQ10 in the human follicular fluid. Although the biological and endocrine mechanism of CoQ10 in the follicular fluid and its correlation with oocyte and embryo development is unclear, a new step may be the administration of CoQ10 in infertile women to evaluate the biological and reproductive outcomes.
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Fertilização/fisiologia , Líquido Folicular/química , Infertilidade Feminina/fisiopatologia , Infertilidade Feminina/terapia , Ubiquinona/análogos & derivados , Adulto , Feminino , Fertilização in vitro , Humanos , Oócitos/fisiologia , Indução da Ovulação , Ubiquinona/análiseRESUMO
Designing fully green materials for flexible electronics is an urgent need due to the growing awareness of an environmental crisis. With the aim of developing a sustainable, printable, and biocompatible material to be exploited in flexible electronics, the rheological, structural and charge transport properties of water-based hydroxypropyl cellulose (HPC)-detonation nanodiamond (DND) viscous dispersions are investigated. A rheological investigation disclosed that the presence of the DND affects the orientation and entanglement of cellulose chains in the aqueous medium. In line with rheological analyses, the NMR diffusion experiments pointed out that the presence of DND modifies the hydrodynamic behavior of the cellulose molecules. Despite the increased rigidity of the system, the presence of DND slightly enhances the ionic conductivity of the dispersion, suggesting a modification in the charge transport properties of the material. The electrochemical analyses, performed through Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS), revealed that the HPC-DND system is remarkably stable in the explored voltage range (-0.1 to +0.4 V) and characterized by a lowered bulk resistance with respect to HPC. Such features, coupled with the printability and filmability of the material, represent good requirements for the exploitation of such systems in flexible electronic applications.
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In several biomedical applications, the detection of biomarkers demands high sensitivity, selectivity and easy-to-use devices. Organic electrochemical transistors (OECTs) represent a promising class of devices combining a minimal invasiveness and good signal transduction. However, OECTs lack of intrinsic selectivity that should be implemented by specific approaches to make them well suitable for biomedical applications. Here, we report on a biosensor in which selectivity and a high sensitivity are achieved by interfacing, in an OECT architecture, a novel gate electrode based on aptamers, Au nanoparticles and graphene hierarchically organized to optimize the final response. The fabricated biosensor performs state of the art limit of detection monitoring biomolecules, such as thrombin-with a limit of detection in the picomolar range (≤ 5 pM) and a very good selectivity even in presence of supraphysiological concentrations of Bovine Serum Albumin (BSA-1mM). These accomplishments are the final result of the gate hierarchic structure that reduces sterich indrance that could contrast the recognition events and minimizes false positive, because of the low affinity of graphene towards the physiological environment. Since our approach can be easily applied to a large variety of different biomarkers, we envisage a relevant potential for a large series of different biomedical applications.
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Endometriosis is a debilitating condition characterized by high recurrence rates. The etiology and pathogenesis remain unclear. Typically, endometriosis causes pain and infertility, although 20-25% of patients are asymptomatic. The principal aims of therapy include relief of symptoms, resolution of existing endometriotic implants, and prevention of new foci of ectopic endometrial tissue. Current therapeutic approaches are far from being curative; they focus on managing the clinical symptoms of the disease rather than fighting the disease. Specific combinations of medical, surgical, and psychological treatments can ameliorate the quality of life of women with endometriosis. The benefits of these treatments have not been entirely demonstrated, particularly in terms of expectations that women hold for their own lives. Although theoretically advantageous, there is no evidence that a combination medical-surgical treatment significantly enhances fertility, and it may unnecessarily delay further fertility therapy. Randomized controlled trials are required to demonstrate the efficacy of different treatments.
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Endometriose/complicações , Infertilidade Feminina/etiologia , Endometriose/epidemiologia , Endometriose/terapia , Feminino , Fertilização in vitro , Humanos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/terapiaRESUMO
The interfacing of artificial devices with biological systems is a challenging field that crosses several disciplines ranging from fundamental research (biophysical chemistry, neurobiology, material and surface science) to frontier technological application (nanotechnology, bioelectronics). The memristor is the fourth fundamental circuit element, whose electrical properties favor applications in signal processing, neural networks, and brain-computer interactions and it represents a new frontier for technological applications in many fields including the nanotechnologies, bioelectronics and the biosensors. Using multidisciplinary approaches, covering surface science, cell biology and electrophysiology, we successfully implemented a living bio-hybrid system constituted by cells adhering to films of poly(aniline) (PANI), a semiconductor polymer having memristive properties assembled with polyelectrolytes. Here we tested whether the PANI devices could support survivor, adhesion and differentiation of several cell lines, including the neuron-like SHSY5Y cells. Moreover, we performed electrophysiology on these cells showing that the biophysical properties are retained with differences occurring in the recorded ion currents. Taken together, the cell viability here reported is the key requirement to design and develop a reliable functional memristor-based bio-hybrid able to mimic neuronal activity and plasticity.
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Compostos de Anilina/química , Adesão Celular , Sobrevivência Celular , Eletrólitos/química , Células HEK293 , Células HeLa , Humanos , Semicondutores , Propriedades de SuperfícieRESUMO
OBJECTIVE: To evaluate the role of a dedicated neurosonographer in prenatal diagnosis of isolated complete agenesis of the corpus callosum (iCACC) and to asses the postnatal outcome of these infants. METHODS: Prospective study between January 2004 to December 2004 at Fetal Maternal Medical Centre 'Artemisia', Rome, Italy. A detailed ultrasound scan was performed in fetuses affected by iCACC by a dedicated fetal neurosonographer (CG). In all cases, magnetic resonance imaging (MRI) within 5 weeks and 13-15 months after birth was performed. A comparison was made between prenatal findings following the ultrasound scan and postnatal MRI. In these cases, a follow-up of 4-years was performed with a neurological evaluation. RESULTS: Among 23 cases of ACC diagnosed at our centre in the study period, CACC was diagnosed in 17 fetuses. Two were then excluded due to associated malformations, one was lost at follow-up and one patient opted to terminate her pregnancy. Newborn MRI confirmed the ultrasonographic diagnosis of iCACC in all 13 cases. A regular development was present in 92.3% of prenatally diagnosed iCACC. CONCLUSION: A dedicated neurosonographer could diagnose the iCACC with the same accuracy as MRI and in up to 90% of cases the newborn will have a regular development.