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991.
992.
Rocco Cappellesso Filippo Nozzoli Federica Zito Marino Sara Simi Francesca Castiglione Vincenzo De Giorgi Carlo Cota Rebecca Senetta Giosu Scognamiglio Anna Maria Anniciello Anna Maria Cesinaro Mario Mandal Andrea Gianatti Maria Gabriella Valente Barbara Valeri Angela Rita Sementa Costantino Ricci Barbara Corti Giandomenico Roviello Angelo Paolo Dei Tos Renato Franco Daniela Massi 《International journal of molecular sciences》2021,22(22)
Atypical Spitz tumors (AST) deviate from stereotypical Spitz nevi for one or more atypical features and are now regarded as an intermediate category of melanocytic tumors with uncertain malignant potential. Activating NTRK1/NTRK3 fusions elicit oncogenic events in Spitz lesions and are targetable with kinase inhibitors. However, their prevalence among ASTs and the optimal approach for their detection is yet to be determined. A series of 180 ASTs were screened with pan-TRK immunohistochemistry and the presence of NTRK fusions was confirmed using FISH, two different RNA-based NGS panels for solid tumors, and a specific real time RT-PCR panel. Overall, 26 ASTs showed pan-TRK immunostaining. NTRK1 fusions were detected in 15 of these cases showing cytoplasmic immunoreaction, whereas NTRK3 was detected in one case showing nuclear immunoreaction. Molecular tests resulted all positive in only two ASTs (included the NTRK3 translocated), RNA-based NGS and real time RT-PCR were both positive in three cases, and FISH and real time RT-PCR in another two cases. In seven ASTs NTRK1 fusions were detected only by FISH and in two cases only by real time RT-PCR. The frequency of NTRK fusions in ASTs is 9%, with a clear prevalence of NTRK1 compared to NTRK3 alterations. Pan-TRK immunohistochemistry is an excellent screening test. Confirmation of NTRK fusions may require the use of different molecular techniques. 相似文献
993.
Through differential scanning calorimetry, isothermal crystallization from the melt of polytetrafluoroethylene (PTFE) has been investigated. PTFE was regarded as one of the polymers for which crystallization is so rapid that the samples crystallize during the cooling from the melt to the selected crystallization temperature. By contrast, we now report that a stochastic behavior is observed for isothermal melt‐crystallization of PTFE. In fact, on cooling very quickly the samples from the molten state to the selected crystallization temperature, crystallization during the cooling is randomly observed. Therefore, repeating the experiments until crystallization on cooling was absent, it was possible to investigate isothermal melt‐crystallization of PTFE. However, crystallization is very fast; in fact, crystallization kinetics can be followed just for very low undercoolings, while as the undercooling becomes as large as about 15°C, only secondary crystallization is observed. In both cases, the data have been examined through the well‐known Avrami analysis, taking into account the different physical meaning of the obtained parameters. For the first cases (actual crystallization kinetics) very low, noninteger Avrami exponents have been obtained. They have been related to the fractal dimension of the crystallites and their values to the morphological observations on PTFE. For the second cases, the typical low values of Avrami exponents of secondary crystallization are obtained. Moreover, isothermal melt‐crystallization of random fluorinated copolymers of tetrafluoroethylene with either hexafluoropropylene or perfluoromethylvinylether as comonomers has been studied and compared with that of PTFE. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1607–1613, 1999 相似文献
994.
Elena Chugunova Nurgali Akylbekov Alexey Dobrynin Alexander Burilov Carla Boga Gabriele Micheletti Vincenzo Frenna Edoardo Jun Mattioli Matteo Calvaresi Domenico Spinelli 《International journal of molecular sciences》2021,22(24)
This research focuses on the X-ray structure of 4,6-dichloro-5-nitrobenzofuroxan 1 and of some of its amino derivatives (4a, 4e, 4g, and 4l) and on DFT calculations concerning the nucleophilic reactivity of 1. We have found that by changing the solvent used for crystallization, it is possible to obtain 4,6-dichloro-5-nitrobenzofuroxan (1) in different polymorphic structures. Moreover, the different torsional angles observed for the nitro group in 1 and in its amino derivatives (4a, 4e, 4g, and 4l) are strictly dependent on the steric hindrance of the substituent at C-4. DFT calculations on the course of the nucleophilic substitution confirm the role of the condensed furoxan ring in altering the aromaticity of the carbocyclic frame, while chlorine atoms strongly influence the dihedral angle and the rotational barrier of the nitro group. These results corroborate previous observations based on experimental kinetic data and give a deep picture of the reaction with amines, which proceeds via a “non-aromatic” nucleophilic substitution. 相似文献
995.
Chiara Camponeschi Maria De Carluccio Susanna Amadio Maria Elisabetta Clementi Beatrice Sampaolese Cinzia Volont Maria Tredicine Vincenzo Romano Spica Rosa Di Liddo Francesco Ria Fabrizio Michetti Gabriele Di Sante 《International journal of molecular sciences》2021,22(24)
S100B is an astrocytic protein behaving at high concentration as a damage-associated molecular pattern molecule. A direct correlation between the increased amount of S100B and inflammatory processes has been demonstrated, and in particular, the inhibitor of S100B activity pentamidine has been shown to ameliorate clinical scores and neuropathologic-biomolecular parameters in the relapsing-remitting experimental autoimmune encephalomyelitis mouse model of multiple sclerosis. This study investigates the effect of arundic acid (AA), a known inhibitor of astrocytic S100B synthesis, in the chronic experimental autoimmune encephalomyelitis, which is another mouse model of multiple sclerosis usually studied. By the daily evaluation of clinical scores and neuropathologic-molecular analysis performed in the spinal cord, we observed that the AA-treated group showed lower severity compared to the vehicle-treated mice, particularly in the early phase of disease onset. We also observed a significant reduction of astrocytosis, demyelination, immune infiltrates, proinflammatory cytokines expression and enzymatic oxidative reactivity in the AA-treated group. Overall, our results reinforce the involvement of S100B in the development of animal models of multiple sclerosis and propose AA targeting the S100B protein as a focused potential drug to be considered for multiple sclerosis treatment. 相似文献
996.
Francesco Caponio Vincenzo Alloggio Cosimo Pallavicini 《European Journal of Lipid Science and Technology》1998,100(3):74-78
The lipid fraction of goat milk was subjected to transesterification using a commercially available immobilized lipase to decrease the amount of short- and medium-chain fatty acids (C4–C14) by enrichment of the reaction mixture with long-chain (C18:1 and C18:2) fatty acids. Aliquots were taken during, transesterification at different reaction times and analyzed for triglycerides and their fatty acid components. The gas chromatographic analyses of triglycerides (previously isolated by thinlayer chromatography) showed that at 6 h reaction under the experimental conditions led to the greatest reduction of the low molecular weight triglycerides (C22–C38) and concomitantly to the greatest increase in the higher molecular weight triglycerides (C48–C54). These changes correlated with the variations observed in the fatty acids of the triglyceride fraction. 相似文献
997.
Simone Di Micco Veronica Di Sarno Martina Rossi Vincenzo Vestuto Takumi Konno Sara Novi Mario Felice Tecce Valeria Napolitano Tania Ciaglia Andrea Vitale Isabel Maria Gomez-Monterrey Giuseppe Bifulco Alessia Bertamino Carmine Ostacolo Paolo Blasi Alessio Fasano Pietro Campiglia Simona Musella 《International journal of molecular sciences》2023,24(1)
Different molecular mechanisms contribute to the development of multidrug resistance in cancer, including increased drug efflux, enhanced cellular repair mechanisms and alterations of drug metabolism or drug targets. ABCG2 is a member of the ATP-binding cassette superfamily transporters that promotes drug efflux, inducing chemotherapeutic resistance in malignant cells. In this context, the development of selective ABCG2 inhibitors might be a suitable strategy to improve chemotherapy efficacy. Thus, through a multidisciplinary approach, we identified a new ABCG2 selective inhibitor (8), highlighting its ability to increase mitoxantrone cytotoxicity in both hepatocellular carcinoma (EC50from 8.67 ± 2.65 to 1.25 ± 0.80 μM) and transfected breast cancer cell lines (EC50from 9.92 ± 2.32 to 2.45 ± 1.40 μM). Moreover, mitoxantrone co-administration in both transfected and non-transfected HEK293 revealed that compound 8 notably lowered the mitoxantrone EC50, demonstrating its efficacy along with the importance of the ABCG2 extrusion pump overexpression in MDR reversion. These results were corroborated by evaluating the effect of inhibitor 8 on mitoxantrone cell uptake in multicellular tumor spheroids and via proteomic experiments. 相似文献
998.
Valentina Vassallo Antonietta Stellavato Rosita Russo Donatella Cimini Mariangela Valletta Alberto Alfano Paolo Vincenzo Pedone Angela Chambery Chiara Schiraldi 《International journal of molecular sciences》2022,23(24)
Pharma-grade extractive chondroitin sulfate (CS) is widely used for osteoarthritis (OA) treatment. Recently, unsulfated biofermentative chondroitin (BC) proved positive effects in OA in vitro model. This study, based on primary pathological human synoviocytes, aimed to analyze, by a multiplex assay, a panel of OA-related biomarkers in response to short-term treatments with bovine (CSb), pig (CSp) and fish (CSf) chondroitins, in comparison to BC. As expected, all samples had anti-inflammatory properties, however CSb, CSf and especially BC affected more cytokines and chemokines. Based on these results and molecular weight similarity, CSf and BC were selected to further explore the synoviocytes’ response. In fact, Western blot analyses showed CSf and BC were comparable, downregulating OA-related biomarkers such as the proteins mTOR, NF-kB, PTX-3 and COMP-2. Proteomic analyses, performed by applying a nano-LC-MS/MS TMT isobaric labelling-based approach, displayed the modulation of both common and distinct molecules to chondroitin treatments. Thus, CSf and BC modulated the biological mediators involved in the inflammation cascade, matrix degradation/remodeling, glycosaminoglycans’ synthesis and cellular homeostasis. This study helps in shedding light on different molecular mechanisms related to OA disease that may be potentially affected not only by animal-source chondroitin sulfate but also by unsulfated biofermentative chondroitin. 相似文献
999.
Simona Sagona Chiara DOnofrio Vincenzo Miragliotta Antonio Felicioli 《International journal of molecular sciences》2022,23(24)
The occurrence of the honeybee caste polyphenism arises when a change in diet is transduced into cellular metabolic responses, resulting in a developmental shift mediated by gene expression. The aim of this investigation was to detect and describe the expression profile of water-soluble proteases during the ontogenesis of honeybee worker-fate larvae. The extraction of insect homogenates was followed by the electrophoretic separation of the protein extract in polyacrylamide gels under semi-denaturing condition, precast with gelatin, pollen, or royal jelly protein extracts. The worker-fate honeybee larva showed a proteolytic pattern that varied with aging, and a protease with the highest activity at 72 h after hatching was named PS4. PS4 has a molecular weight of 45 kDa, it remained active until cell sealing, and its enzymatic properties suggest a serine-proteinase nature. To define the process that originates a queen-fate larvae, royal jelly and pollen were analysed, but PS4 was not detected in either of them. The effect of food on the PS4 was investigated by mixing crude extracts of queen and worker-fate larvae with pollen and royal jelly, respectively. Only royal jelly inhibited PS4 in worker-fate larvae. Taken together, our data suggest that PS4 could be involved in caste differentiation. 相似文献
1000.
Maila Chirivì Claudia Bearzi Paolo Rosa Selenia Miglietta Francesca Petronella Elena De Falco Antonella Calogero Roberto Pani Vincenzo Petrozza Giovanni Perotto Roberto Rizzi Luciano De Sio 《International journal of molecular sciences》2022,23(17)
Before entering human clinical studies to evaluate their safety and effectiveness, new drugs and novel medical treatments are subject to extensive animal testing that are expensive and time-consuming. By contrast, advanced technologies enable the development of animal-free models that allow the efficacy of innovative therapies to be studied without sacrificing animals, while providing helpful information and details. We report on the powerful combination of 3D bioprinting (3DB) and photo-thermal therapy (PTT) applications. To this end, we realize a 3DB construct consisting of glioblastoma U87-MG cells in a 3D geometry, incorporating biomimetic keratin-coated gold nanoparticles (Ker-AuNPs) as a photo-thermal agent. The resulting plasmonic 3DB structures exhibit a homogeneous cell distribution throughout the entire volume while promoting the localization of Ker-AuNPs within the cells. A 3D immunofluorescence assay and transmission electron microscopy (TEM) confirm the uniform distribution of fluorescent-labeled Ker-AuNPs in the volume and their capability to enter the cells. Laser-assisted (λ = 532 nm) PTT experiments demonstrate the extraordinary ability of Ker-AuNPs to generate heating, producing the highest temperature rise of about 16 °C in less than 2 min. 相似文献