805 research outputs found
PDE4 Inhibitors: Profiling Hits through the Multitude of Structural Classes
Cyclic nucleotide phosphodiesterases 4 (PDE4) are a family of enzymes which specifically promote the hydrolysis and degradation of cAMP. The inhibition of PDE4 enzymes has been widely investigated as a possible alternative strategy for the treatment of a variety of respiratory diseases, including chronic obstructive pulmonary disease and asthma, as well as psoriasis and other autoimmune disorders. In this context, the identification of new molecules as PDE4 inhibitors continues to be an active field of investigation within drug discovery. This review summarizes the medicinal chemistry journey in the design and development of effective PDE4 inhibitors, analyzed through chemical classes and taking into consideration structural aspects and binding properties, as well as inhibitory efficacy, PDE4 selectivity and the potential as therapeutic agents
A Data-Driven Slip Estimation Approach for Effective Braking Control under Varying Road Conditions
The performances of braking control systems for robotic platforms, e.g.,
assisted and autonomous vehicles, airplanes and drones, are deeply influenced
by the road-tire friction experienced during the maneuver. Therefore, the
availability of accurate estimation algorithms is of major importance in the
development of advanced control schemes. The focus of this paper is on the
estimation problem. In particular, a novel estimation algorithm is proposed,
based on a multi-layer neural network. The training is based on a synthetic
data set, derived from a widely used friction model. The open loop performances
of the proposed algorithm are evaluated in a number of simulated scenarios.
Moreover, different control schemes are used to test the closed loop scenario,
where the estimated optimal slip is used as the set-point. The experimental
results and the comparison with a model based baseline show that the proposed
approach can provide an effective best slip estimation
Review of Methodologies and Metrics for Assessing the Quality of Random Number Generators
Random number generators are a key element for various applications, such as computer simulation, statistical sampling, and cryptography. They are used to generate/derive cryptographic keys and non-repeating values, e.g., for symmetric or public key cyphers. The strength of a data protection system against cyber attacks corresponds to the strength of the weakest point in the security chain. Therefore, from a mathematical point of view, the security chain can be compromised even if the strongest algorithm is implemented. In fact, if the system requires keys or other random values and the generation process shows a certain vulnerability, the security of the system itself can be compromised. In this article, we present the most reliable tools and methodologies and the main standardisation efforts in the field of computer security to assess the quality of random number generators and ensure that they can be applied to computer security applications by offering adequate security strength. We offer a comprehensive guide that can be used as a quick and practical reference by developers of random number generators of any type to evaluate the random bit streams generated by implemented modules and determine whether or not they can be used in cybersecurity applications. Finally, we also present some use cases to which we applied the presented approach
The Longitudinal Interplay between Sleep, Anthropometric Indices, Eating Behaviors, and Nutritional Aspects: A Systematic Review and Meta-Analysis
Sleep is fundamental for adolescents’ healthy development but undergoes dramatic changes in quantity and quality due to the conflict between biological and social rhythms. Insufficient sleep has been associated with worse physical health status and irregular eating behaviors in adolescents. This review aims to systematically synthesize the longitudinal associations between adolescents’ sleep dimensions (i.e., duration, timing, quality, and insomnia symptoms) and physical health indicators (i.e., anthropometric indices, fat percentage, and risk of obesity), eating behaviors, and nutritional aspects (i.e., type of diet related to the intake of specific foods and nutrients, amount and timing of food consumption, energy expenditure). A total of 28 longitudinal studies were included. The meta-analytic results showed that longer sleep duration, better sleep quality, and lower insomnia symptoms were associated with lower BMI and fat percentage and that shorter sleep duration (<7 h) and lower sleep quality were associated with a higher risk of obesity. Conversely, anthropometric indices were not related to sleep over time. Limited literature examined the bidirectional association between adolescents’ sleep and their eating behaviors and nutritional aspects. Such knowledge sheds new light on the role of sleep for adolescents’ health, highlighting the need to examine further the interplay between these variables
Basic knowledge and new advances in panoramic radiography imaging techniques: A narrative review on what dentists and radiologists should know
Objectives: A panoramic radiograph (PAN) is the most frequently diagnostic imaging technique carried out in dentistry and oral surgery. The correct performance of image acquisition is crucial to obtain adequate image quality. The aim of the present study is to (i) review the principles of PAN image acquisition and (ii) describe positioning errors and artefacts that may affect PAN image quality. Methods: Articles regarding PAN acquisition principles, patient’s positioning errors, artefacts, and image quality were retrieved from the literature. Results: Head orientation is of the utmost importance in guaranteeing correct image acquisition. Symmetry, occlusal plane inclination, mandibular condyles localization, cervical spine position, aspect of upper teeth root apexes, exposure parameters, and metal and motion artefacts are factors that greatly affect the image quality of a successful PAN. Conclusions: Several factors are the basis for PAN performance; therefore, a systematic approach that takes into account correct patient positioning and preparation is strongly suggested to improve overall examination quality
Psychometric properties of the Italian Tinnitus Functional Index (TFI)
Diversi questionari sono utilizzati per valutare l\u2019impatto dell\u2019acufene sulla qualit\ue0 della vita. Il Tinnitus Functional Index (TFI) proposto da Meikle et al, nel 2012, ha dimostrato propriet\ue0 eccellenti per misurare la gravit\ue0 e le modificazioni indotte dal trattamento degli acufeni, sia in ambito clinico che di ricerca. Lo scopo di questo studio \ue8 stato valutare le propriet\ue0 psicometriche della versione italiana del TFI, in particolare, l\u2019analisi fattoriale, la consistenza interna, l\u2019affidabilit\ue0 e la validit\ue0. La versione originale inglese del TFI \ue8 stata tradotta in italiano secondo la procedura translation - back translation; 137 partecipanti con acufeni da almeno 3 mesi (39,4% femmine, et\ue0: 18-80 anni, et\ue0 media: 48,26, SD: 14,08), reclutati presso la Tinnitus Clinic di Milano, hanno completato la versione italiana del TFI, il Tinnitus Handicap Inventory, la Beck Depression Inventory - Versione Primary Care e la scala di valutazione numerica per il fastidio. Una parte del campione, 57 pazienti, ha completato la versione italiana del TFI in una seconda visita, dopo 7-14 giorni, prima di ricevere qualsiasi tipo di trattamen- to, per ricavare i dati per la valutazione della riproducibilit\ue0. Le propriet\ue0 psicometriche sono state studiate attraverso un\u2019analisi fattoriale esplorativa ed il calcolo di misure di consistenza interna e affidabilit\ue0 test-retest. La validit\ue0 convergente \ue8 stata valutata mediante i coefficienti di correlazione con le restanti misure. La versione italiana del TFI ha mostrato una struttura a quattro fattori, parzialmente diversa dalla struttura originale a otto fattori. L\u2019adattamento italiano del TFI ha rivelato buoni livelli di consistenza interna (0,92 64 \u3b1 64 0,96) e affidabilit\ue0 test-retest (0,79 64 \u3b1 64 0,85). In termini di validit\ue0 convergente, ha mostrato buone correlazioni con i punteggi del THI (r = 0,77) e della scala del fastidio (r = 0,70) e correlazioni medie con i punteggi del BDI (r = 0,46). Le difficolt\ue0 nel riprodurre la struttura originale a otto fattori sono coerenti con altri studi di validazione del TFI nelle lingue europee. Nonostante tali discrepanze, la versione italiana del TFI ha mostrato una struttura fattoriale caratterizzata da alti livelli di affidabilit\ue0 e validit\ue0. Nel complesso, l\u2019adattamento italiano di TFI si \ue8 rivelato idoneo a misurare l\u2019impatto degli acufeni sulla vita quotidiana degli individui.Various questionnaires are used to assess the impact of tinnitus on the quality of life. The Tinnitus Functional Index (TFI) has excellent properties for scaling the severity of tinnitus and treatment-related changes in both clinical and research settings. The aim of this study was to evaluate the psychometric properties of the Italian version of the TFI with particular emphasis on factor analysis, internal consistency, reliability and validity. The original English version of the TFI was translated into Italian using the translation/back - translation process; 137 participants who were re- cruited at the Tinnitus Clinic in Milan and had suffered from tinnitus for at least three months (39.4% females, age: 18-80 years, mean age: 48.26, SD: 14.08) completed the Italian version of the TFI, the Tinnitus Handicap Inventory (THI), the Beck Depression Inventory - Primary Care Version (BDI-PC) and the Numeric Rating Scale of annoyance (NRS-A). Of these patients, 57 completed the TFI again at a second visit 7-14 days later, before undergoing any intervention, in order to provide data for reproducibility assessment. The psychometric properties were investigated using exploratory factor analysis and internal consistency and test-retest reliability instruments. The convergent validity of the TFI was evalu- ated using correlation coefficients obtained from the remaining measurements. The Italian TFI has a four-factor structure that was somewhat different from the original. The internal consistency proved to be good (0.92 64 \u3b1 64 0.96) as did the test-retest reliability (0.79 64 \u3b1 64 0.85). In terms of convergent validity, the TFI showed high correlations with the THI (r = 0.77) and the NRS-A (r = 0.70) scores, and moderate correlations with the BDI-PC scores (r = 0.46). The difficulties encountered when attempting to reproduce the original eight-factor structure were consistent with other studies in which the TFI was translated into European languages. In spite of this, the factorial structure of the Italian version of the TFI was characterised by high levels of reliability and validity. Overall, the Italian adaptation of the TFI was shown to be suitable to measure the impact of tinnitus on the daily lives of individuals
AI-driven ground robots: mobile edge computing and mmWave communications at work
The seamless integration of multiple radio access technologies (multi-RAT) and cloud/edge resources is pivotal for advancing future networks, which seek to unify distributed and heterogeneous computing and communication resources into a cohesive continuum system, tailored for mobile applications. Many research projects and focused studies are proposing solutions in this area, the impact of which is undoubtedly increased by moving from theoretical and simulation studies to experimental validations. To this aim, this paper proposes a testbed architecture that combines contemporary communication and cloud technologies to provide microservice-based mobile applications with the ability to offload part of their tasks to cloud/edge data centers connected by multi-RAT cellular networks. The testbed leverages Kubernetes, Istio service mesh, OpenFlow, public 5G networks, and IEEE 802.11ad mmWave (60 GHz) Wi-Fi access points. The architecture is validated through a use case in which a ground robot autonomously follows a moving object by using an artificial intelligence-driven computer vision application. Computationally intensive navigation tasks are offloaded by the robot to microservice instances, which are executed on demand within cloud and edge data centers that the robot can exploit during its journey. The proposed testbed is flexible and can be reused to assess communication and cloud innovations focusing on multi-RAT cloud continuum scenarios
Optimization of 4-amino-pyridazin-3(2H)-one as a valid core scaffold for FABP4 inhibitors
Current clinical research suggests that fatty acid-binding protein 4 inhibitors (FABP4is), which are of biological and therapeutic interest, may show potential in treating cancer and other illnesses. We sought to uncover new structures through the optimization of the previously reported 4-amino and 4-ureido pyridazinone-based series of FABP4is as part of a larger research effort to create more potent FABP4 inhibitors. This led to the identification of 14e as the most potent analog with IC₅₀ = 1.57 μM, which is lower than the IC₅₀ of the positive control. Advanced modeling investigations and in silico absorption, distribution, metabolism, and excretion - toxicity calculations suggested that 14e represents a potential candidate for in vivo studies such as FABP4i
Ligand Growing Experiments Suggested 4-amino and 4-ureido pyridazin-3(2H)-one as Novel Scaffold for FABP4 Inhibition
Fatty acid binding protein (FABP4) inhibitors are of synthetic and therapeutic interest and ongoing clinical studies indicate that they may be a promise for the treatment of cancer, as well as other diseases. As part of a broader research effort to develop more effective FABP4 inhibitors, we sought to identify new structures through a two-step computing assisted molecular design based on the established scaffold of a co-crystallized ligand. Novel and potent FABP4 inhibitors have been developed using this approach and herein we report the synthesis, biological evaluation and molecular docking of the 4-amino and 4-ureido pyridazinone-based series
Further studies on pyrazolo[1',5':1,6]pyrimido[4,5-d]pyridazin-4(3H)-ones as potent and selective human A1 adenosine receptor antagonists.
A new series of pyrazolo[1',5':1,6]pyrimido[4,5-dlpyridazin-4(3H)-ones was synthesized and tested in radioligand binding assays on human A(1), A(2A) and A(3) adenosine receptors. Most of the compounds showed high selectivity of action towards A(1) receptor and high affinity with K-i values in the low nanomolar range. The pharmacological profile of the most active molecules towards A(1) adenosine receptors was evaluated in cAMP functional assay. Compounds demonstrated their ability to completely counteract the effect of the agonist NECA, thus demonstrating their antagonist profile. Moreover, the most interesting compound, tested in the mouse passive avoidance, exhibited an antiamnesic effect at the doses of 10 and 30 mg/kg. (C) 2014 Published by Elsevier Masson SAS
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