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71.
Matej Vizovisek Dragana Ristanovic Stefano Menghini Michael G. Christiansen Simone Schuerle 《International journal of molecular sciences》2021,22(5)
In recent decades, dysregulation of proteases and atypical proteolysis have become increasingly recognized as important hallmarks of cancer, driving community-wide efforts to explore the proteolytic landscape of oncologic disease. With more than 100 proteases currently associated with different aspects of cancer development and progression, there is a clear impetus to harness their potential in the context of oncology. Advances in the protease field have yielded technologies enabling sensitive protease detection in various settings, paving the way towards diagnostic profiling of disease-related protease activity patterns. Methods including activity-based probes and substrates, antibodies, and various nanosystems that generate reporter signals, i.e., for PET or MRI, after interaction with the target protease have shown potential for clinical translation. Nevertheless, these technologies are costly, not easily multiplexed, and require advanced imaging technologies. While the current clinical applications of protease-responsive technologies in oncologic settings are still limited, emerging technologies and protease sensors are poised to enable comprehensive exploration of the tumor proteolytic landscape as a diagnostic and therapeutic frontier. This review aims to give an overview of the most relevant classes of proteases as indicators for tumor diagnosis, current approaches to detect and monitor their activity in vivo, and associated therapeutic applications. 相似文献
72.
Betemps DL Fachinello JC Galarça SP Portela NM Remorini D Massai R Agati G 《Journal of the science of food and agriculture》2012,92(9):1855-1864
BACKGROUND: The detection of pigments and colourless flavonoids in apples can provide a useful indication of fruit quality. Optical methods are preferable because they are fast and non‐destructive. In this study, a fluorescence‐based portable sensor was used in order to non‐invasively determine the content of chlorophylls, anthocyanins and flavonols in Fuji, Granny Smith and Golden Delicious apple cultivars. The aim was to define new non‐destructive optical indices of apple quality. RESULTS: The anthocyanin index (ANTH) in Fuji was higher in the sunny (i.e. sun‐exposed) side of the fruit compared to the shady side. For all cultivars, the flavonol index (FLAV) was higher in the sunny side compared with the shady side. The chlorophyll index (CHL) for the shady sides of Granny Smith and Golden Delicious was significantly higher than for the sunny sides. Fine linear regressions were found between the ANTH, FLAV and CHL indices and the actual anthocyanin, flavonol and chlorophyll concentrations, respectively, which were determined destructively on the apple peel extracts. A negative correlation was found between the apple sugar content and the chlorophyll fluorescence in the far‐red spectral band. CONCLUSION: Our results indicate that a single multiparametric fluorescence‐based sensor can provide valuable non‐destructive markers of ripening and quality in apples. Copyright © 2012 Society of Chemical Industry 相似文献
73.
Luca Cornolti Simone Martinelli Giovanni Bianchi Alberto Ortona 《Journal of the American Ceramic Society》2019,102(5):2304-2315
In this work, we investigated a procedure which exploits microwave ovens to produce SiC- based components by reactive melt infiltration of silicon into graphite preforms. The employed oven is designed to grant optical access to the sample surface, which allows to measure its temperature evolution though a noncontact pyrometer. This signal was used as a feedback to control the power provided to the preform and as an experimental output whose analysis provides insight into the reaction mechanism. Specifically, it is found that complete infiltration is achieved much before the end of the reaction. The latter is not fully self-sustained as the global reaction rate continuously decreases with time until it is no more able to keep the temperature above the silicon solidification value. At that point, the reaction stops. The analysis of the processed samples proved that this procedure allows producing fully infiltrated samples without material failure by adjusting the heat provided during the infiltration stage rather than by tuning the preform structure and composition, which is the usual approach. The proposed method is less time and energy consuming than the standard one. 相似文献
74.
Dr. Riccardo De Ricco Dr. Daniela Valensin Dr. Simone Dell'Acqua Prof. Dr. Luigi Casella Dr. Christelle Hureau Prof. Dr. Peter Faller 《Chembiochem : a European journal of chemical biology》2015,16(16):2319-2328
Copper binding to α‐synuclein (aS) and to amyloid‐β (Ab) has been connected to Parkinson's and Alzheimer's disease (AD), respectively, because Cu ions can modulate the peptide aggregation, and these Cu ? peptide complexes can catalyse the production of reactive oxygen species (ROS). In a significant proportion of AD brains, aggregation of aS and Ab has been detected, and it was proposed that Ab and aS interact with each other. Thus, we investigated the potential interactions of Ab and aS through their binding of copper(I) and copper(II). Additionally, β‐synuclein (bS) was investigated, due to its additional methionine residue, a potential CuI ligand. We found that: 1) the peptides containing the Cu‐binding domains Ab1–16, aS1–15 and bS1–15 have similar affinities towards CuII and towards CuI, with Ab1–16 being slightly stronger, 2) in the case of CuI, the additional Met residue in bS1–15 increased the affinity slightly, 3) the exchange of CuI/II between the two peptides is rapid (≤ms), 4) a/bS1–15 and Ab1–16 form a heterodimeric complex with CuII, 5) CuI probably promotes a transient ternary complex, 6) the different CuI/II coordination of Ab1–16, aS1–15 and bS1–15 impacts the capacity to produce ROS and to oxidise catechol, and 7) when Ab1–16, aS1–15 and Cu are present, the ROS production more closely resembles that by Ab1–16. The work gives insights into the coordination chemistry of these related peptides, and the relevance of coordination differences, the ternary complex and ROS production are discussed. 相似文献
75.
Designing Dual Transglutaminase 2/Histone Deacetylase Inhibitors Effective at Halting Neuronal Death 下载免费PDF全文
Dr. Manuela Basso Dr. Huan Huan Chen Dr. Debasmita Tripathy Dr. Mariarosaria Conte Dr. Kim Y. P. Apperley Dr. Angela De Simone Prof. Dr. Jeffrey W. Keillor Prof. Dr. Rajiv Ratan Dr. Angela Nebbioso Dr. Federica Sarno Prof. Dr. Lucia Altucci Dr. Andrea Milelli 《ChemMedChem》2018,13(3):227-230
In recent years there has been a clear consensus that neurodegenerative conditions can be better treated through concurrent modulation of different targets. Herein we report that combined inhibition of transglutaminase 2 (TG2) and histone deacetylases (HDACs) synergistically protects against toxic stimuli mediated by glutamate. Based on these findings, we designed and synthesized a series of novel dual TG2–HDAC binding agents. Compound 3 [(E)‐N‐hydroxy‐5‐(3‐(4‐(3‐oxo‐3‐(pyridin‐3‐yl)prop‐1‐en‐1‐yl)phenyl)thioureido)pentanamide] emerged as the most interesting of the series, being able to inhibit TG2 and HDACs both in vitro (TG2 IC50=13.3±1.5 μm , HDAC1 IC50=3.38±0.14 μm , HDAC6 IC50=4.10±0.13 μm ) and in cell‐based assays. Furthermore, compound 3 does not exert any toxic effects in cortical neurons up to 50 μm and protects neurons against toxic insults induced by glutamate (5 mm ) with an EC50 value of 3.7±0.5 μm . 相似文献
76.
Small and large scale segmental motion in polymers: estimating cooperativity length by ordinary relaxation experiments 下载免费PDF全文
Marco Pieruccini Andrea Alessandrini Simone Sturniolo Maurizio Corti Attilio Rigamonti 《Polymer International》2015,64(11):1506-1512
We derive a suitable expression for estimating the size of the cooperatively rearranging regions (CRRs) in supercooled polymer melts by fitting data worked out by ordinary relaxation experiments carried out in isothermal conditions. As an example, the average CRR size in poly(n‐butyl methacrylate) in proximity to the glass transition temperature is derived from a stress relaxation experiment performed by means of an atomic force microscopy setup. Good agreement is found with results in the literature derived from measurements of temperature fluctuations (the so‐called Donth method). The temperature dependence of the CRR size is explored for poly(butadiene); in this case the segmental relaxation function is derived through a novel method for the analysis of the efficiency with which free induction decay echoes are refocused in 1H NMR experiments. It is found that the CRR size increases upon cooling. The results derived from the analysis of the NMR data are found to be in satisfactory agreement with those worked out from broadband dielectric spectroscopy data in the literature. © 2015 Society of Chemical Industry 相似文献
77.
Jekaterina Hermane Ilona Bułyszko Dr. Simone Eichner Dr. Florenz Sasse Wera Collisi Prof. Dr. Antti Poso Emilia Schax Dr. Johanna‐Gabriela Walter Prof. Dr. Thomas Scheper Dr. Klaus Kock Prof. Dr. Christian Herrmann Dr. Pooyan Aliuos Prof. Dr. Günter Reuter Priv.‐Doz. Dr. Carsten Zeilinger Prof. Dr. Andreas Kirschning 《Chembiochem : a European journal of chemical biology》2015,16(2):302-311
Streptomyces hygroscopicus is a natural producer of geldanamycin. Mutasynthetic supplementation of an AHBA‐blocked mutant with all possible monofluoro 3‐aminobenzoic acids provided new fluorogeldanamycins. These showed strong antiproliferative activity and inhibitory effects on human heat shock protein Hsp90. Binding to Hsp90 in the low nanomolar range was determined from molecular modelling, AFM analysis and by calorimetric studies. 相似文献
78.
Simone Ceriani Giulio Fontana Alessandro Giusti Daniele Marzorati Matteo Matteucci Davide Migliore Davide Rizzi Domenico G. Sorrenti Pierluigi Taddei 《Autonomous Robots》2009,27(4):353-371
A trustable and accurate ground truth is a key requirement for benchmarking self-localization and mapping algorithms; on the
other hand, collection of ground truth is a complex and daunting task, and its validation is a challenging issue. In this
paper we propose two techniques for indoor ground truth collection, developed in the framework of the European project Rawseeds, which are mutually independent and also independent on the sensors onboard the robot. These techniques are based, respectively,
on a network of fixed cameras, and on a network of fixed laser scanners. We show how these systems are implemented and deployed,
and, most importantly, we evaluate their performance; moreover, we investigate the possible fusion of their outputs. 相似文献
79.
The paper presents a new lossless ECG compression scheme. The short-term predictor and the coder use conditioning on a small number of contexts. The long-term prediction is based on an algorithm for R-R interval estimation. Several QRS detection algorithms are investigated to select a low complexity and reliable detection algorithm. The coding of prediction residuals uses primarily the Golomb-Rice (GR) codes, but, to improve the coding results, escape codes GR-ESC are used in some contexts for a limited number of samples. Experimental results indicate the good overall performance of the lossless ECG compression algorithms (reducing the storage needs from 12 to about 3-4 bits per sample). The scheme consistently outperforms other waveform or general purpose coding algorithms. 相似文献
80.
Simone Fujii Ricardo Marcelo Reche Ribeiro Maria Brígida Dos Santos Scholz Elisabete Yurie Sataque Ono Cássio Egidio C Prete Eiko Nakagawa Itano Yoshio Ueno Osamu Kawamura Elisa Yoko Hirooka 《Food Additives & Contaminants》2006,23(9):902-909
The performance of an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on a monoclonal antibody (mAb) for ochratoxin A (OTA) detection was evaluated in a comparative study with high-performance liquid chromatography (HPLC) analysis using 68 freshly harvested coffee samples from the North of Paraná State, Brazil. The anti-OTA mAb showed high specificity and low cross-reactivity with OTA analogues (OTB and OTalpha), but cross-reacted with OTC. This ic-ELISA showed a detection limit of 3.75 ngg-1 sample, when compared to 0.80 ngg-1 by HPLC, with an ic-ELISA/HPLC correlation coefficient of 0.90. As regards OTA analysis of these coffee samples, natural contamination was detected in 10 samples (14.7%) by both methods, where the ic-ELISA values (range 3.9-7.3 ngg-1) were 1.1 to 1.6-fold higher than HPLC data (2.7-4.7 ngg-1). Five samples (7.4%) were OTA positive (range 0.84-1.30 ngg-1) only by HPLC assay, probably due to the higher detection limit reached by ic-ELISA. OTA was undetectable in 53 samples (77.9%) by both methods, while all positive samples (range 0.84-7.30 ngg-1) showed OTA levels lower than 8 ngg-1 (maximum limit recommended by the European Union). The matrix interference of green coffee was minimized by dilution of sample extracts before carrying out the ELISA assay. This mAb-based ic-ELISA can be effectively applied for OTA screening in coffee, because it is simple, sensitive and sample preparation is easy. 相似文献