Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 104
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 119(4)2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35042814

RESUMEN

We unravel the interplay of topological properties and the layered (anti)ferromagnetic ordering in EuSn2P2, using spin and chemical selective electron and X-ray spectroscopies supported by first-principle calculations. We reveal the presence of in-plane long-range ferromagnetic order triggering topological invariants and resulting in the multiple protection of topological Dirac states. We provide clear evidence that layer-dependent spin-momentum locking coexists with ferromagnetism in this material, a cohabitation that promotes EuSn2P2 as a prime candidate axion insulator for topological antiferromagnetic spintronics applications.

2.
Nano Lett ; 24(5): 1487-1493, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38285518

RESUMEN

van der Waals materials provide a versatile toolbox for the emergence of new quantum phenomena and fabrication of functional heterostructures. Among them, the trihalide VI3 stands out for its unique magnetic and structural landscape. Here we investigate the spin and orbital magnetic degrees of freedom in the layered ferromagnet VI3 by means of temperature-dependent X-ray absorption spectroscopy and X-ray magnetic circular and linear dichroism. We detect localized electronic states and reduced magnetic dimensionality, due to electronic correlations. We furthermore provide experimental evidence of (a) an unquenched orbital magnetic moment (up to 0.66(7) µB/V atom) in the ferromagnetic state and (b) an instability of the orbital moment in the proximity of the spin reorientation transition. Our results support a coherent picture where electronic correlations give rise to a strong magnetic anisotropy and a large orbital moment and establish VI3 as a prime candidate for the study of orbital quantum effects.

3.
Nano Lett ; 23(17): 8035-8042, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37638737

RESUMEN

Engineering surfaces and interfaces of materials promises great potential in the field of heterostructures and quantum matter designers, with the opportunity to drive new many-body phases that are absent in the bulk compounds. Here, we focus on the magnetic Weyl kagome system Co3Sn2S2 and show how for the terminations of different samples the Weyl points connect differently, still preserving the bulk-boundary correspondence. Scanning tunneling microscopy has suggested such a scenario indirectly, and here, we probe the Fermiology of Co3Sn2S2 directly, by linking it to its real space surface distribution. By combining micro-ARPES and first-principles calculations, we measure the energy-momentum spectra and the Fermi surfaces of Co3Sn2S2 for different surface terminations and show the existence of topological features depending on the top-layer electronic environment. Our work helps to define a route for controlling bulk-derived topological properties by means of surface electrostatic potentials, offering a methodology for using Weyl kagome metals in responsive magnetic spintronics.

4.
BMC Cancer ; 23(1): 1194, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057796

RESUMEN

BACKGROUND: Myxofibrosarcoma is a rare malignant soft tissue sarcoma characterised by multiple local recurrence and can become of higher grade with each recurrence. Consequently, myxofibrosarcoma represents a burden for patients, a challenge for clinicians, and an interesting disease to study tumour progression. Currently, few myxofibrosarcoma preclinical models are available. METHODS: In this paper, we present a spontaneously immortalised myxofibrosarcoma patient-derived cell line (MF-R 3). We performed phenotypic characterization through multiple biological assays and analyses: proliferation, clonogenic potential, anchorage-independent growth and colony formation, migration, invasion, AgNOR staining, and ultrastructural evaluation. RESULTS: MF-R 3 cells match morphologic and phenotypic characteristics of the original tumour as 2D cultures, 3D aggregates, and on the chorioallantoic membrane of chick embryos. Overall results show a clear neoplastic potential of this cell line. Finally, we tested MF-R 3 sensitivity to anthracyclines in 2D and 3D conditions finding a good response to these drugs. CONCLUSIONS: In conclusion, we established a novel patient-derived myxofibrosarcoma cell line that, together with the few others available, could serve as an important model for studying the molecular pathogenesis of myxofibrosarcoma and for testing new drugs and therapeutic strategies in diverse experimental settings.


Asunto(s)
Fibrosarcoma , Histiocitoma Fibroso Maligno , Sarcoma , Animales , Adulto , Humanos , Embrión de Pollo , Fibrosarcoma/tratamiento farmacológico , Fibrosarcoma/patología , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Línea Celular Tumoral
5.
Nano Lett ; 22(17): 7034-7041, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36039834

RESUMEN

Two-dimensional van der Waals magnetic semiconductors display emergent chemical and physical properties and hold promise for novel optical, electronic and magnetic "few-layers" functionalities. Transition-metal iodides such as CrI3 and VI3 are relevant for future electronic and spintronic applications; however, detailed experimental information on their ground state electronic properties is lacking often due to their challenging chemical environment. By combining X-ray electron spectroscopies and first-principles calculations, we report a complete determination of CrI3 and VI3 electronic ground states. We show that the transition metal-induced orbital filling drives the stabilization of distinct electronic phases: a wide bandgap in CrI3 and a Mott insulating state in VI3. Comparison of surface-sensitive (angular-resolved photoemission spectroscopy) and bulk-sensitive (X-ray absorption spectroscopy) measurements in VI3 reveals a surface-only V2+ oxidation state, suggesting that ground state electronic properties are strongly influenced by dimensionality effects. Our results have direct implications in band engineering and layer-dependent properties of two-dimensional systems.

6.
Int J Mol Sci ; 24(8)2023 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-37108089

RESUMEN

Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) can be considered as a spectrum of the same disease entity, representing one of the most common adult soft tissue sarcoma (STS) of the extremities. While MFS is rarely metastasizing, it shows an extremely high rate of multiple frequent local recurrences (50-60% of cases). On the other hand, UPS is an aggressive sarcoma prone to distant recurrence, which is correlated to a poor prognosis. Differential diagnosis is challenging due to their heterogeneous morphology, with UPS remaining a diagnosis of exclusion for sarcomas with unknown differentiation lineage. Moreover, both lesions suffer from the unavailability of diagnostic and prognostic biomarkers. In this context, a genomic approach combined with pharmacological profiling could allow the identification of new predictive biomarkers that may be exploited for differential diagnosis, prognosis and targeted therapy, with the aim to improve the management of STS patients. RNA-Seq analysis identified the up-regulation of MMP13 and WNT7B in UPS and the up-regulation of AKR1C2, AKR1C3, BMP7, and SGCG in MFS, which were confirmed by in silico analyses. Moreover, we identified the down-regulation of immunoglobulin genes in patient-derived primary cultures that responded to anthracycline treatment compared to non-responder cultures. Globally, the obtained data corroborated the clinical observation of UPS as an histotype refractory to chemotherapy and the key role of the immune system in determining chemosensitivity of these lesions. Moreover, our results confirmed the validity of genomic approaches for the identification of predictive biomarkers in poorly characterized neoplasms as well as the robustness of our patient-derived primary culture models in recapitulating the chemosensitivity features of STS. Taken as a whole, this body of evidence may pave the way toward an improvement of the prognosis of these rare diseases through a treatment modulation driven by a biomarker-based patient stratification.


Asunto(s)
Fibrosarcoma , Histiocitoma Fibroso Maligno , Sarcoma , Neoplasias de los Tejidos Blandos , Adulto , Humanos , Sarcoma/diagnóstico , Sarcoma/tratamiento farmacológico , Sarcoma/genética , Neoplasias de los Tejidos Blandos/patología , Extremidades/patología , Genómica
7.
Phys Chem Chem Phys ; 24(44): 27328-27342, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36326290

RESUMEN

The cytotoxicity of ionic liquids (ILs) has been receiving attention in the context of the biological and environmental impact of their vast field of applications. It has been ascertained that the cell membrane is the main target of ILs when they interact with microorganisms, cells and bacteria; nevertheless, studies at the micro- and nano-scale aiming at better understanding of the fundamental mechanisms of toxicity of ILs are lacking. In this work, we used atomic force microscopy (AFM) to investigate the impact of room-temperature ILs on the mechanical, morphological and electrostatic properties of solid-supported DOPC phospholipid bilayers, taken as models of biomembranes. In particular, we have characterized the concentration-dependent and time-dependent evolution of the morphological, structural and mechanical properties of DOPC lipid membranes in the presence of imidazolium-based ILs with different alkyl chain lengths and hydrophilic/hydrophobic characteristics. The majority of ILs investigated were found to possess the ability of restructuring the lipid bilayer, through the formation of new IL/lipid complexes, showing distinctive morphological features (increase of area and roughness). The nanomechanical analysis of the lipid membrane exposed to ILs revealed a progressive, concentration-dependent perturbation of the structural ordering and rigidity of the membrane, evidenced by a decrease in the breakthrough force, Young's modulus and area stretching modulus. AFM detected a modification of the electrostatic double-layer at the membrane surface, in terms of a reduction of the original negative surface charge density, suggesting a progressive stratification of cations on the exposed leaflet of the lipid membrane. Our findings may be helpful in designing novel ILs with tailored interaction with biological membranes.


Asunto(s)
Líquidos Iónicos , Fosfolípidos , Membrana Dobles de Lípidos , Membrana Celular , Microscopía de Fuerza Atómica
8.
Int J Mol Sci ; 23(6)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35328661

RESUMEN

In the clinical management of solid tumors, the possibility to successfully couple the regeneration of injured tissues with the elimination of residual tumor cells left after surgery could open doors to new therapeutic strategies. In this work, we present a composite hydrogel-electrospun nanofiber scaffold, showing a modular architecture for the delivery of two pharmaceutics with distinct release profiles, that is potentially suitable for local therapy and post-surgical treatment of solid soft tumors. The composite was obtained by coupling gelatin hydrogels to poly(ethylene oxide)/poly(butylene terephthalate) block copolymer nanofibers. Results of the scaffolds' characterization, together with the analysis of gelatin and drug release kinetics, displayed the possibility to modulate the device architecture to control the release kinetics of the drugs, also providing evidence of their activity. In vitro analyses were also performed using a human epithelioid sarcoma cell line. Furthermore, publicly available expression datasets were interrogated. Confocal imaging showcased the nontoxicity of these devices in vitro. ELISA assays confirmed a modulation of IL-10 inflammation-related cytokine supporting the role of this device in tissue repair. In silico analysis confirmed the role of IL-10 in solid tumors including 262 patients affected by sarcoma as a negative prognostic marker for overall survival. In conclusion, the developed modular composite device may provide a key-enabling technology for the treatment of soft tissue sarcoma.


Asunto(s)
Nanofibras , Neoplasias de los Tejidos Blandos , Alquenos , Sistemas de Liberación de Medicamentos , Óxido de Etileno , Gelatina , Humanos , Hidrogeles , Interleucina-10 , Óxidos , Ácidos Ftálicos , Poliésteres , Polietilenglicoles , Tereftalatos Polietilenos , Ingeniería de Tejidos , Andamios del Tejido
9.
Small ; 17(26): e2100050, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34061425

RESUMEN

The femtosecond evolution of the electronic temperature of laser-excited gold nanoparticles is measured, by means of ultrafast time-resolved photoemission spectroscopy induced by extreme-ultraviolet radiation pulses. The temperature of the electron gas is deduced by recording and fitting high-resolution photo emission spectra around the Fermi edge of gold nanoparticles providing a direct, unambiguous picture of the ultrafast electron-gas dynamics. These results will be instrumental to the refinement of existing models of femtosecond processes in laterally-confined and bulk condensed-matter systems, and for understanding more deeply the role of hot electrons in technological applications.

10.
Neuroendocrinology ; 111(9): 895-906, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33221806

RESUMEN

BACKGROUND: Neuroendocrine neoplasias (NENs) are a rare group of tumors with different prognosis and response to therapy. Their heterogeneity is dependent on the site of origin, morphology, and Ki67. Temozolomide (TEM) appears to be active in metastatic NENs (mNENs) but there is limited evidence about its efficacy in gastrointestinal NENs. We analyzed "real-world" data on the use of TEM alone or in association with capecitabine (CAPTEM) in patients with mNENs. PATIENTS AND METHODS: One hundred consecutive patients with advanced NENs treated with TEM or CAPTEM between 2009 and 2019 were included. A pretreatment tumor growth rate (TGR0) was calculated. Overall survival (OS), progression-free survival (PFS), tolerance, objective response rate (ORR), and disease control rate (DCR) were analyzed. A propensity score analysis and inverse probability of treatment weights for Cox regression models were used. RESULTS: TEM-based therapy was administered to 95 patients (26.3% CAPTEM and 83.7% TEM) with a median age of 59 years (range 26-85) years. ECOG performance status was 0-2. Carcinoid syndrome was reported in 12 (12.6%) patients. Twenty (21.1%) patients with grade (G) 3 neuroendocrine carcinoma (NEC) and 9 (9.4%) with G3 neuroendocrine tumors (NETs) were included in the analysis. Median PFS of the entire group was 10.4 months (95% confidence interval [CI]: 6.0-11.5). In multivariate analysis, a higher risk of progression was observed for NEC G3 patients (hazard ratio [HR] 2.70, 95% CI: 1.25-5.84) and for a TGR ≥19.55 (HR: 2.53, 95% CI: 1.45-4.40). Median OS was 23.4 months (95% CI: 17.0-29.0) and was similar in both treatment groups (23.9 vs. 20.5 months for TEM and CAPTEM, respectively, p = 0.585). In multivariate analysis, TGR ≥19.55 was associated with a higher risk of death (HR: 2.18, 95% CI: 1.16-4.11) than TGR <19.55, as was NEC G3 (HR: 2.42, 95% CI: 1.04-5.59) with respect to NETs. No differences in terms of mPFS or mOS were seen in relation to the primary site of disease. In the 86 patients evaluable for response, ORR was 44.1% and the DCR was 70.9%. Mild adverse events (grade I-II) included anemia, neutropenia, and headache. Rare cases of G 3 neutropenia and thrombocytopenia were recorded. CONCLUSIONS: TEM-based regimens are associated with a high DCR and a relatively tolerable toxicity profile in NENs of pancreatic, intestinal, and lung origin. Further investigation of these specific NETs is warranted in prospective clinical trials.


Asunto(s)
Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica , Capecitabina/farmacología , Tumores Neuroendocrinos/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Temozolomida/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Capecitabina/administración & dosificación , Capecitabina/efectos adversos , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Temozolomida/administración & dosificación , Temozolomida/efectos adversos
11.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34299136

RESUMEN

Soft tissue sarcomas (STSs) are a family of rare malignant tumors encompassing more than 80 histologies. Current therapies for metastatic STS, a condition that affects roughly half of patients, have limited efficacy, making innovative therapeutic strategies urgently needed. From a molecular point of view, STSs can be classified as translocation-related and those with a heavily rearranged genotype. Although only the latter display an increased mutational burden, molecular profiles suggestive of an "immune hot" tumor microenvironment are observed across STS histologies, and response to immunotherapy has been reported in both translocation-related and genetic complex STSs. These data reinforce the notion that immunity in STSs is multifaceted and influenced by both genetic and epigenetic determinants. Cumulative evidence indicates that a fine characterization of STSs at different levels is required to identify biomarkers predictive of immunotherapy response and to discover targetable pathways to switch on the immune sensitivity of "immune cold" tumors. In this review, we will summarize recent findings on the interplay between genetic landscape, molecular profiling and immunity in STSs. Immunological and molecular features will be discussed for their prognostic value in selected STS histologies. Finally, the local and systemic immunomodulatory effects of the targeted drugs imatinib and sunitinib will be discussed.


Asunto(s)
Biomarcadores de Tumor/antagonistas & inhibidores , Regulación Neoplásica de la Expresión Génica , Inmunoterapia/métodos , Terapia Molecular Dirigida , Sarcoma/inmunología , Microambiente Tumoral/inmunología , Animales , Biomarcadores de Tumor/inmunología , Humanos , Sarcoma/tratamiento farmacológico , Sarcoma/patología
12.
Int J Mol Sci ; 22(21)2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34768995

RESUMEN

Adult rhabdomyosarcoma (RMS) represents an uncommon entity with an incidence of less than 3% of all soft tissue sarcomas (STS). Consequently, the natural history and the clinical management of this disease are infrequently reported. In order to fill this gap, we investigated the molecular biology of an adult RMS case series. The expression of epithelial mesenchymal transition-related gene and chemoresistance-related gene panels were evaluated. Moreover, taking advantage of our STS translational model combining patient-derived primary culture and 3D-scaffold, the pharmacological profile of an adult head and neck sclerosing RMS was assessed. Furthermore, NGS, microsatellite instability, and in silico analyses were carried out. RT-PCR identified the upregulation of CDH1, SLUG, MMP9, RAB22a, S100P, and LAPTM4b, representing promising biomarkers for this disease. Pharmacological profiling showed the highest sensitivity with anthracycline-based regimen in both 2D and 3D culture systems. NGS analysis detected RAB3IP-HMGA2 in frame gene rearrangement and FGFR4 mutation; microsatellite instability analysis did not detect any alteration. In silico analysis confirmed the mutation of FGFR4 as a promising marker for poor prognosis and a potential therapeutic target. We report for the first time the molecular and pharmacological characterization of rare entities of adult head and neck and posterior trunk RMS. These preliminary data could shed light on this poorly understood disease.


Asunto(s)
Rabdomiosarcoma/genética , Adulto , Anciano , Biomarcadores de Tumor/genética , Transición Epitelial-Mesenquimal/genética , Femenino , Genómica/métodos , Humanos , Masculino , Inestabilidad de Microsatélites , Mutación/genética , Sarcoma/genética , Neoplasias de los Tejidos Blandos/genética , Regulación hacia Arriba
13.
Small ; 16(36): e1907693, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32643290

RESUMEN

Current investigations into hazardous nanoparticles (i.e., nanotoxicology) aim to understand the working mechanisms that drive toxicity. This understanding has been used to predict the biological impact of the nanocarriers as a function of their synthesis, material composition, and physicochemical characteristics. It is particularly critical to characterize the events that immediately follow cell stress resulting from nanoparticle internalization. While reactive oxygen species and activation of autophagy are universally recognized as mechanisms of nanotoxicity, the progression of these phenomena during cell recovery has yet to be comprehensively evaluated. Herein, primary human endothelial cells are exposed to controlled concentrations of polymer-functionalized silica nanoparticles to induce lysosomal damage and achieve cytosolic delivery. In this model, the recovery of cell functions lost following endosomal escape is primarily represented by changes in cell distribution and the subsequent partitioning of particles into dividing cells. Furthermore, multilamellar bodies are found to accumulate around the particles, demonstrating progressive endosomal escape. This work provides a set of biological parameters that can be used to assess cell stress related to nanoparticle exposure and the subsequent recovery of cell processes as a function of endosomal escape.


Asunto(s)
Células Endoteliales , Nanopartículas , Polímeros , Dióxido de Silicio , Línea Celular , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Modelos Biológicos , Nanopartículas/metabolismo , Nanopartículas/toxicidad , Polímeros/química , Dióxido de Silicio/toxicidad
14.
J Org Chem ; 85(5): 3454-3464, 2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32027511

RESUMEN

The replacement of carbon atoms at the zigzag periphery of a benzo[fg]tetracenyl derivative with an NBN atomic triad allows the formation of heteroatom-doped polycyclic aromatic hydrocarbon (PAH) isosteres, which expose BN mimics of the amidic NH functions. Their ability to form H-bonded complexes has never been touched so far. Herein, we report the first solution recognition studies of peripherally NBN-doped PAHs to form H-bonded DD·AA- and ADDA·DAAD-type complexes with suitable complementary H-bonding acceptor partners. The first determination of Ka in solution showed that the 1:1 association strength is around 27 ± 1 M-1 for the DD·AA complexes in C6D6, whereas it rises to 1820 ± 130 M-1 for the ADDA·DAAD array in CDCl3. Given the interest of BN-doped polyaromatic hydrocarbons in supramolecular and materials chemistry, it is expected that these findings will open new possibilities to design novel materials, where the H-bonding properties of peripheral NH hydrogens could serve as anchors to tailor the organizational properties of PAHs.

15.
Int J Clin Pract ; 73(11): e13404, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31408256

RESUMEN

BACKGROUND: Patients undergoing chemotherapy are at risk of toxicity, especially of haematological origin. Granulocyte depletion, although often underestimated, can lead to the occurrence of an event defined as febrile neutropenia (FN). Neutropenic fever syndromes are dangerous because they cause major complications in around 25%-30% of patients and have a mortality rate of up to 11%. Treatment for FN was limited to antibiotics and supportive therapies until filgrastim was approved for use in the 1990s. OBJECTIVES: The present systematic review focuses on the efficacy and safety of this haematopoietic growth factor. DATA SOURCES AND METHODS: For this review, a systematic literature search of electronic databases and references from recent reviews up to December 2018 was carried out to identify clinical trials, observational studies and case reports evaluating filgrastim efficacy and safety. English language was defined as a restriction. Published randomised controlled trials (RCTs), case reports and reviews analysing the effects of filgrastim on severe neutropenia and its limits were considered. Four review authors independently selected the studies, assessed the risk of bias and extracted study data. RESULTS: As reported in ASCO guidelines, the efficacy of filgrastim with respect to placebo or no treatment in RCTs is based on its prevention of FN. A recent meta-analysis analysed nine RCTs with 2197 patients, revealing a reduction in the incidence of FN with filgrastim (risk ratio [RR] 0.63, 95% CI 0.53-0.75). These findings were further confirmed in two observational studies. Bone pain is the most commonly reported adverse event with filgrastim, while other toxicities are associated with filgrastim efficacy and with an increased neutrophil count. KEY FINDINGS: In conclusion, our findings attest to the previous results on the efficacy and safety of filgrastim.


Asunto(s)
Filgrastim/uso terapéutico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Fármacos Hematológicos/uso terapéutico , Neutropenia/prevención & control , Antibacterianos/uso terapéutico , Humanos , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
J Chem Phys ; 148(24): 241739, 2018 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-29960375

RESUMEN

We assess Gaussian process (GP) regression as a technique to model interatomic forces in metal nanoclusters by analyzing the performance of 2-body, 3-body, and many-body kernel functions on a set of 19-atom Ni cluster structures. We find that 2-body GP kernels fail to provide faithful force estimates, despite succeeding in bulk Ni systems. However, both 3- and many-body kernels predict forces within an ∼0.1 eV/Šaverage error even for small training datasets and achieve high accuracy even on out-of-sample, high temperature structures. While training and testing on the same structure always provide satisfactory accuracy, cross-testing on dissimilar structures leads to higher prediction errors, posing an extrapolation problem. This can be cured using heterogeneous training on databases that contain more than one structure, which results in a good trade-off between versatility and overall accuracy. Starting from a 3-body kernel trained this way, we build an efficient non-parametric 3-body force field that allows accurate prediction of structural properties at finite temperatures, following a newly developed scheme [A. Glielmo et al., Phys. Rev. B 95, 214302 (2017)]. We use this to assess the thermal stability of Ni19 nanoclusters at a fractional cost of full ab initio calculations.

17.
J Am Chem Soc ; 139(50): 18271-18280, 2017 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-29064236

RESUMEN

The E/Z isomerization process of a uracil-azobenzene derivative in which the nucleobase is conjugated to a phenyldiazene tail is studied in view of its ability to form triply H-bonded complexes with a suitably complementary 2,6-diacetylamino-4-pyridine ligand. UV-vis and 1H NMR investigations of the photochemical and thermal isomerization kinetics show that the thermal Z → E interconversion is 4-fold accelerated upon formation of the H-bonded complex. DFT calculations show that the formation of triple H-bonds triggers a significant elongation of the N═N double bond, caused by an increase of its πg* antibonding character. This results in a reduction of the N═N torsional barrier and thus in accelerated thermal Z → E isomerization. Combined with light-controlled E → Z isomerization, this enables controllable fractional tuning of the two configurational isomers.

18.
J Transl Med ; 15(1): 229, 2017 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-29116016

RESUMEN

The use of patient-derived primary cell cultures in cancer preclinical assays has increased in recent years. The management of resected tumor tissue remains complex and a number of parameters must be respected to obtain complete sample digestion and optimal vitality yield. We provide an overview of the benefits of correct primary cell culture management using different preclinical methodologies, and describe the pros and cons of this model with respect to other kinds of samples. One important advantage is that the heterogeneity of the cell populations composing a primary culture partially reproduces the tumor microenvironment and crosstalk between malignant and healthy cells, neither of which is possible with cell lines. Moreover, the use of patient-derived specimens in innovative preclinical technologies, such as 3D systems or bioreactors, represents an important opportunity to improve the translational value of the results obtained. In vivo models could further our understanding of the crosstalk between tumor and other tissues as they enable us to observe the systemic and biological interactions of a complete organism. Although engineered mice are the most common model used in this setting, the zebrafish (Danio rerio) species has recently been recognized as an innovative experimental system. In fact, the transparent body and incomplete immune system of zebrafish embryos are especially useful for evaluating patient-derived tumor tissue interactions in healthy hosts. In conclusion, ex vivo systems represent an important tool for cancer research, but samples require correct manipulation to maximize their translational value.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Neoplasias/patología , Animales , Reactores Biológicos , Humanos , Investigación Biomédica Traslacional , Células Tumorales Cultivadas , Microambiente Tumoral
19.
Support Care Cancer ; 25(1): 111-117, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27568305

RESUMEN

PURPOSE: Anthracycline and ifosfamide-based chemotherapy represents a widely used regimen both in early and advanced settings in soft tissue sarcoma (STS). Prophylaxis with granulocyte colony-stimulating factor (G-CSF) reduces the severity of chemotherapy-induced neutropenia. The aim of this study was to assess the efficacy and safety of biosimilar G-CSF in these patients. METHODS: Between 2003 and 2013, 67 patients with soft tissue tumors under epirubicin and ifosfamide (EI) treatment receiving biosimilar filgrastim (Zarzio®), originator filgrastim (Granulokine®, Neupogen®), and lenograstim (only originator Myelostim®) as primary prophylaxis for a total of 260 cycles of therapy were retrospectively analyzed. Baseline patient characteristics were summarized in a propensity score (PS). RESULTS: The incidence of febrile neutropenia (FN) was 44.0 % in biosimilar filgrastim, 40.0 % in originator filgrastim, and 45.5 % in the lenograstim groups (p = 0.935). All grade and G4 neutropenia were similar in the three groups with the same safety profile. The use of biosimilar filgrastim achieved cost savings of €225.25 over originator filgrastim and €262.00 over lenograstim. CONCLUSION: Biosimilar G-CSF was effective in preventing FN and in reducing the need for hospitalization in STS patients undergoing EI treatment. It also proved comparable to its reference products from both a clinical and cost-effective standpoint.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neutropenia Febril Inducida por Quimioterapia/prevención & control , Filgrastim/uso terapéutico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Sarcoma/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neutropenia Febril Inducida por Quimioterapia/etiología , Epirrubicina/efectos adversos , Femenino , Fármacos Hematológicos/uso terapéutico , Humanos , Ifosfamida/administración & dosificación , Ifosfamida/efectos adversos , Lenograstim , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Sarcoma/sangre
20.
J Chem Phys ; 147(21): 214706, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-29221400

RESUMEN

We report on the assembly of a highly ordered array of copper tetrameric clusters, coordinated into a metal-organic network. The ordered cluster array has been achieved by the deposition of tetrahydroxyquinone molecules on the Cu(111) surface at room temperature, and subsequent thermally activated dehydrogenation with the formation of tetraoxyquinone tetra-anions with a 4 × 4 periodicity. The supramolecular organic network acts as a spacer for the highly ordered two-dimensional network of copper tetramers at the very surface.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA