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1.
Polymers (Basel) ; 15(22)2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-38006177

RESUMEN

We investigated the effect of nanoscale curvature on the structure of thermally equilibrated poly-3-hexylthiophene (P3HT) ultrathin films. The curvature-induced effects were investigated with synchrotron grazing incidence X-ray diffraction (GIXRD) and atomic force microscopy (AFM). Our results demonstrate that nanoscale curvature reduces the polymer crystalline fraction and the crystal length. The first effect is strongest for the lowest curvature and results in a decrease in the out-of-plane thickness of the polymer crystals. On the other hand, the crystal in-plane length decreases with the increase in substrate curvature. Finally, the semi-quantitative analysis of crystal anisotropy shows a marked dependence on the substrate curvature characterized by a minimum at curvatures between 0.00851 nm-1 and 0.0140 nm-1. The results are discussed in terms of a curvature-dependent polymer fraction, which fills the interstices between neighboring particles and cannot crystallize due to extreme space confinement. This fraction, whose thickness is highest at the lowest curvatures, inhibits the crystal nucleation and the out-of-plane crystal growth. Moreover, because of the adhesion to the curved portion of the substrates, crystals adopt a random orientation. By increasing the substrate curvature, the amorphous fraction is reduced, leading to polymer films with higher crystallinity. Finally, when the thickness of the film exceeds the particle diameter, the curvature no longer affects the crystal orientation, which, similarly to the flat case, is predominantly edge on.

2.
Langmuir ; 38(40): 12281-12291, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36172718

RESUMEN

The lack of methodologies which enable us to measure forces acting between nanomaterials is one of the factors limiting the full comprehension of their behavior and their more effective exploitation in new devices. Here we exploit the irreversible adsorption of surfactant-decorated nanoparticles at the air/water interface to investigate interparticle forces and the effect of the surfactant structure on them. We measured the interparticle repulsive forces as a function of the modulation of the interparticle distance by simultaneously performing compression isotherms and the grazing incidence small-angle X-ray scattering (GISAXS) structural characterization of the monolayers at water-vapor interfaces. Our results demonstrate that the short-range interparticle forces are strongly affected by the presence of the organic ligands, which are shown to be able to influence the interparticle repulsions even when added in micromolar amounts. In particular, we demonstrate the predominant steric nature of short-range forces, which are accounted for in terms of the compression-induced stretched-to-coiled conformational transition of the ligand hydrophobic tail.

3.
Nanoscale ; 13(32): 13650-13657, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34477640

RESUMEN

Novel preparative approaches towards lamellar nanocomposites of carbon and inorganic materials are relevant for a broad range of technological applications. Here, we describe how to utilize the co-assembly of a liquid-crystalline hexaphenylene amphiphile and an aluminosilicate precursor to prepare carbon-aluminosilicate nanocomposites with controlled lamellar orientation and macroscopic order. To this end, the shear-induced alignment of a precursor phase of the two components resulted in thin films comprising lamellae with periodicities on the order of the molecular length scale, an "edge-on" orientation relative to the substrate and parallel to the shearing direction with order on the centimeter length scale. The lamellar structure, orientation, and macroscopic alignment were preserved in the subsequent pyrolysis that yielded the corresponding carbon-aluminosilicate nanocomposites.

4.
Int J Mol Sci ; 22(1)2020 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33379143

RESUMEN

Although translational research has identified a large number of potential biomarkers involved in colorectal cancer (CRC) carcinogenesis, a better understanding of the molecular pathways associated with biological aging in colorectal cells and tissues is needed. Here, we aim to summarize the state of the art about the role of age acceleration, defined as the difference between epigenetic age and chronological age, in the development and progression of CRC. Some studies have shown that accelerated biological aging is positively associated with the risk of cancer and death in general. In line with these findings, other studies have shown how the assessment of epigenetic age in people at risk for CRC could be helpful for monitoring the molecular response to preventive interventions. Moreover, it would be interesting to investigate whether aberrant epigenetic aging could help identify CRC patients with a high risk of recurrence and a worst prognosis, as well as those who respond poorly to treatment. Yet, the application of this novel concept is still in its infancy, and further research should be encouraged in anticipation of future applications in clinical practice.


Asunto(s)
Envejecimiento/metabolismo , Neoplasias Colorrectales/etiología , Metilación de ADN , Epigénesis Genética , MicroARNs/metabolismo , Animales , Carcinogénesis , Humanos
5.
Molecules ; 25(23)2020 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-33291853

RESUMEN

Real-time sensing of chemical warfare agents by optical sensors is today a crucial target to prevent terroristic attacks by chemical weapons. Here the synthesis, characterization and detection properties of a new sensor, based on covalently functionalized carbon nanoparticles, are reported. This nanosensor exploits noncovalent interactions, in particular hydrogen bonds, to detect DMMP, a simulant of nerve agents. The nanostructure of the sensor combined with the supramolecular sensing approach leads to high binding constant affinity, high selectivity and the possibility to reuse the sensor.


Asunto(s)
Sustancias para la Guerra Química/química , Nanopartículas/química , Nanotubos de Carbono/química , Enlace de Hidrógeno , Nanoestructuras/química , Agentes Nerviosos/química
6.
Nanoscale ; 12(44): 22386-22397, 2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33150913

RESUMEN

Molecular communication (MoCo) is a new paradigm of bio-inspired communication in which the transport of information occurs through information particles instead of electromagnetic waves. Herein, the enormous potential of nanoparticles in this field is highlighted. The MoCo concept has been extensively modelled both theoretically and computationally within the scientific community, mainly in the field of engineering. We collected the most relevant findings about the implementation of prototypal MoCo platforms by exploiting nanoparticles as informative nanomessengers and herein the theoretical and computational modelling used to design MoCo systems is presented.

7.
Ann Med Surg (Lond) ; 58: 4-7, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32874569

RESUMEN

We describe a case of a 30-year-old man who complained intermitted pain in right abdominal flank; a large cavernoumatos hemangioma - up to 6 cm in size - was revealed in the fifth hepatic segment using Ultrasonography and MRI (Magnetic Resonance Imaging). Indications for treatment - based on imaging features and clinical data - are briefly discussed in our report, providing also a review of existing literature.

8.
Updates Surg ; 72(3): 793-800, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32632764

RESUMEN

According to the American Joint Committee on Cancer, at least 12 lymph nodes are required to accurately stage locally advanced rectal cancer (LARC). Neoadjuvant chemoradiation therapy (NACRT) reduces the number of lymph nodes retrieved during surgery. In this study, we evaluated the effect of NACRT on lymph node retrieval and prognosis in patients with LARC. We performed an observational study of 142 patients with LARC. Although our analysis was retrospective, data were collected prospectively. Half the patients were treated with NACRT and total mesorectal excision (TME) and the other half underwent TME only. The number of lymph nodes retrieved and the number of metastatic lymph nodes were significantly reduced in the NACRT group (P > 0.001). In the univariate and multivariate analyses, only NACRT and patient age were significantly associated with reduced lymph node retrieval. The number of metastatic lymph nodes and the lymph node ratio (LNR) both had a significant effect on prognosis when the patient population was examined as a whole (P = 0.003 and P = 0.001, respectively). However, the LNR was the only significant, independent prognostic factor in both treatment groups (P = 0.007 for the NACRT group; P = 0.04 for the no-NACRT group). NACRT improves patient prognosis only when the number of metastatic lymph nodes is reduced. The number of metastatic lymph nodes and the LNR are important prognostic factors. Lymph node retrieval remains an indispensable tool for staging and prognostic assessment of patients with rectal carcinoma treated with NACRT.


Asunto(s)
Quimioradioterapia Adyuvante , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Metástasis Linfática/terapia , Terapia Neoadyuvante , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Recto/cirugía , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
9.
Nanoscale ; 12(17): 9817-9823, 2020 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-32338670

RESUMEN

A prototypal molecular Internet of things (IoT) network is reported. Starting from the design of the communication architecture, we have theoretically simulated molecular messenger information exchange by means of fluid-based advection. The objective was to determine the key experimental parameters affecting information storage and transfer efficiency. The first working molecular-IoT prototype, based on a chemical communication network, was then developed. Its selectivity was ensured by employing as many different chemical messengers as networked devices; thus three different carbon nanoparticles, characterized by different fluorescence wavelengths, were employed to ensure an effective communication between three networked actuators.

10.
Ann Med Surg (Lond) ; 47: 50-52, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31641505

RESUMEN

INTRODUCTION: Gallbladder cancer commonly spreads by direct extension to the liver and adjacent organs of the gastrointestinal tract. Ovarian metastases by biliary origin, though known, are a very uncommon finding. PRESENTATION OF CASE: We report a rare metastatic localization by gallbladder cancer, Krukenberg tumor mimicking a primitive ovarian cancer. A comprehensive critical review was performed and suggested strategies were analyzed. DISCUSSION: The prognosis of ovarian metastastes by biliary origin is very poor with an overall survival estimated at around 6 months. The variable clinical presentation, radiology and serum markers make the appropriate histological diagnosis mandatory. CONCLUSION: The presence of Krukenberg tumor should be considered in the work-up of gallbladder cancer.

11.
Ann Ital Chir ; 90: 275-280, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31657350

RESUMEN

AIM: The authors seek to assess whether the lymph node ratio (the ratio of positive nodes divided by the total number of retrieved nodes) could predict the risk of metachronous liver metastases. MATERIAL AND METHODS: A homogeneous group of 280 patients, followed-up for at least 5 years, was evaluated. In order to highlight the groups with the highest risk of metachronous liver metastases, patients were divided into four quartiles groups in relation to the LNR. RESULTS: The number of lymph nodes sampled in group "stage I" was significantly lower. Even if statistical significance between the global LNR and the development of liver metastases has not been reached, the subdivision into quartiles has made it possible to highlight that in the more advanced ratio groups, a higher incidence of metachronous liver metastases (p <0.028) was registered and was a different distribution of patients with or without liver metastasis in function of quartiles (P =0.01). DISCUSSION: The LNR has enabled us to prognosticate patients who are at greater risk of developing metachronous liver metastases. The lower lymph node sampling in the patients with less advanced staging (I) and in patients with nodenegative cancer (I+II) who developed liver metastases, leads us to believe that some patients have been understaged. CONCLUSION: We believe that the LNR, especially in cases of adequate lymph node sampling, is a useful gauge to better sub-stratify "node-positive" patients. KEY WORDS: Colorectal cancer, Liver metastases, Lymph node ratio.


Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Hepáticas/secundario , Índice Ganglionar , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Neoplasias Hepáticas/epidemiología , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo
12.
Soft Matter ; 15(42): 8475-8482, 2019 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-31603450

RESUMEN

The control of self-assembly and the related interactions among nanoparticles (NPs) at liquid surfaces and interfaces represents a stimulating experimental challenge to fully understand the behaviour of nano-colloids confined in a 2D asymmetric environment, in turn prompting the building of novel NP-based functional monolayers. Here, we first investigate the structural evolution of a model mixed surfactant/NP monolayer as a function of the surfactant/NP bulk ratio finding that, at ratios lower than 20, the adsorption at the air/water interface of surfactant-decorated NPs is dominant. We then employed these 2D nano-colloidal monolayers as model systems for grazing incidence small angle X-ray scattering measurements, performed using synchrotron radiation, while compressing the monolayers in a Langmuir trough. The simultaneous determination of the compression work and the related reduction of the inter-particle distance at the interface enabled, for the first time, the quantitative characterization of the forces acting between adsorbed NPs, as well as their dispersion law with the inter-particle distance. Distinct surfactant reorganization processes are proposed to interpret the measured forces and the characteristic inter-particle distances.

13.
Int J Mol Sci ; 20(15)2019 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-31390840

RESUMEN

Colorectal cancer (CRC) represents the third-most common cancer worldwide and one of the main challenges for public health. Despite great strides in the application of neoadjuvant and adjuvant therapies for rectal and colon cancer patients, each of these treatments is still associated with certain adverse effects and different response rates. Thus, there is an urgent need for identifying novel potential biomarkers that might guide personalized treatments for specific subgroups of patients. However, until now, there are no biomarkers to predict the manifestation of adverse effects and the response to treatment in CRC patients. Herein, we provide a systematic review of epidemiological studies investigating epigenetic biomarkers in CRC patients receiving neoadjuvant or adjuvant therapy, and their potential role for the prediction of outcomes and response to treatment. With this aim in mind, we identified several epigenetic markers in CRC patients who received surgery with adjuvant or neoadjuvant therapy. However, none of them currently has the robustness to be translated into the clinical setting. Thus, more efforts and further large-size prospective studies and/or trials should be encouraged to develop epigenetic biomarker panels for personalized prevention and medicine in CRC cancer.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Colorrectales/genética , Epigénesis Genética , Epigenómica , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/terapia , Islas de CpG , Metilación de ADN , Epigenómica/métodos , Humanos , MicroARNs/genética , Epidemiología Molecular , Terapia Neoadyuvante , Oportunidad Relativa , Resultado del Tratamiento
14.
Phys Chem Chem Phys ; 21(29): 16223-16229, 2019 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-31298236

RESUMEN

Artificial chemical communication is an emerging field of study driven by the need of exchanging information in delicate environments where standard procedures based on electromagnetic waves cannot be used. A non-synchronized artificial chemical communication system, based on a new modulation technique, namely reaction shift keying (RSK), is presented. The RSK implies that the quenchers are injected into the transmitter, the chemical messenger reacts and a chemically modified messenger travels towards the receiver. Encoding of "0" is obtained by means of the emission of a messenger that reaches the receiver once chemically modified. To encode the value "1", the messenger is not subjected to chemical reaction. Fluorescent carbon nanoparticle molecular messengers that exploit the reaction with Cu(ii) ions for signal modulation were synthesized. A prototypal RSK modulated chemical communication system is developed, from simulations of the communication platform to an operating prototypal system.

15.
Nanoscale ; 11(30): 14203-14209, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31271403

RESUMEN

Herein, supramolecular carbon nanoparticle aggregates were obtained via covalent functionalization of the shell of nanoparticles with triazine and subsequent hydrogen bonding reticulation upon the addition of naphthalene diimide. The resulting reticulated nanoparticles maintained the optical properties required for artificial chemical communication but exhibited a reduced diffusion coefficient, enabling sharper and more intense molecular bit capabilities when employed as chemical messengers. As a result, they are ideal candidates for the transport of information along extended fluid paths. We believe that our results represent a further step towards the understanding and optimization of all the experimental parameters affecting the information transfer efficiency in artificial chemical communication.

16.
Cancers (Basel) ; 11(2)2019 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-30791468

RESUMEN

KCNMA1 is a gene located at 10q22 that encodes the pore-forming α-subunit of the large-conductance Ca2+-activated K⁺ channel. KCNMA1 is down-regulated in gastric carcinoma tumors, through hypermethylation of its promoter. In the present study, we have evaluated the expression levels of KCNMA1 both in a mouse model of Colorectal Cancer (CRC) and in human CRC samples. Additionally, epigenetic mechanisms of KCNMA1 gene regulation were investigated. We observed a significant down-regulation of KCNMA1 both in a human and mouse model of CRC. No differences in KCNMA1 levels were, however, observed at different TNM stages. We also wanted to determine whether the modulation in KCNMA1 was dependent on epigenetic mechanisms. A statistically significant inverse correlation between KCNMA1 expression and mir-17-5p levels was observed in patients with CRC. Furthermore, in the tumor samples, we found a significant hypermethylation of the promoter, in the loci cg24113782 and cg25655799, compared to healthy tissue. Overall, our data suggest the possible use of KCNMA1 as a therapeutic target in the early stages of CRC.

17.
J Invest Surg ; 32(1): 1-7, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28972442

RESUMEN

Purpose/aim: The appropriate staging of colorectal cancer requires at least 12 lymph nodes to be sampled. We evaluated whether lymph node sampling (LNS) and lymph node ratio (LNR) can predict the prognosis of stage II-III patients. MATERIALS AND METHODS: This is a retrospective study on 432 patients classified in LNS ≥12 and LNS <12. Disease-free survival (DFS) was computed using the Kaplan-Meier method. We stratified stage III patients into 4 quartiles base on LNR values. To determine the optimal LNR cut-off, receiver operating characteristic (ROC) curve analysis was performed. RESULTS: There was a positive association between the number of lymph node sampled and the number of metastatic lymph nodes (p < 0.01). Among stage II patients, the DFS was 81% for LNS ≥ 12 and 72% for LNS < 12 (p = 0.158). Among stage III patients, the DFS was 58% (p < 0.001). We found a significant association between LNR quartiles and relapse in stage III patients but only in the LNS ≥ 12 group. ROC curve analysis indicated an ideal LNR cut-off value at 0.194 (sensitivity 65% and specificity 61%). The DFS of patients with LNR below 0.194 was 71%, and that of patients with LNR above 0.194 was 45% (log-rank test, p < 0.001). In the patients with LNS ≥ 12, the cut-off of 0.257 could predict recurrence (specificity 86%). CONCLUSIONS: Stage II patients with LNS < 12 tend to have shorter DFS than stage II patients with LNS ≥ 12. In stage III patients, an appropriate LNR cut-off is a better prognostic predictor than LNR quartile, especially in patients with LNS ≥ 12.


Asunto(s)
Neoplasias Colorrectales/patología , Escisión del Ganglio Linfático/estadística & datos numéricos , Metástasis Linfática/patología , Recurrencia Local de Neoplasia/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/cirugía , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Análisis de Supervivencia
18.
Phys Chem Chem Phys ; 20(48): 30312-30320, 2018 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-30484449

RESUMEN

Molecular communication exploits functional molecular systems travelling along fluid media to deliver messages encoded as concentration pulses, e.g. molecular bits. As the bits are naturally broadened by diffusion, limiting the distance along which information can be transferred, by careful design and optimization of the molecular messengers, is required. A new paradigm, exploiting the chemical reactivity of a suitable molecular messenger, has been developed to achieve long range information transfer with variable transmitter-receiver distances. The experimental results and theoretical simulations, carried out by using fluorescent molecules switched by pH-driven hydrolysis, are reported here. In particular, we simulated the information transport process by using numerical solutions of differential equations governing information swapping and we show that by exploiting the reactivity of the chemical messenger, a stable signal at the receiver is maintained within a wide range of distance. This theoretical prediction was fully experimentally verified by using a prototypal molecular communication platform.

19.
Langmuir ; 34(39): 11706-11713, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30199641

RESUMEN

We have developed a novel approach enabling us to follow and facilitate the formation of two-dimensional coordination polymer monolayers directly at the air/water interface without the need of complex instrumentation. The method is based on the use of a surface active ligand that, when spread at the air/water interface, progressively undergoes hydrolysis with consequent gradual decrease in surface pressure. Notably, if the aqueous subphase contains metal ions capable of coordinating the ligand, coordination competes with hydrolysis, resulting in a lower surface pressure decrease. As a consequence, the formation of the coordination polymer monolayer can be verified simply by surface pressure measurements. Competition between hydrolysis and coordination was investigated as a function of the main experimental parameters affecting the two reactions, enabling the formation of stable coordination polymer monolayers with controlled density. Finally, the formation of continuous rigid 2D layers was confirmed by compression isotherms and ex situ morphological characterization. This work will simplify the verification of coordination polymer monolayer formation; thus, it will boost the synthesis of novel and innovative 2D materials.

20.
J Phys Chem Lett ; 8(16): 3861-3866, 2017 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-28767249

RESUMEN

The modeling and realization of an effective communication platform for long-range information transfer is reported. Messages are encrypted in molecular bits by concentration pulses of fluorescent carbon quantum dots having self-quenching emission that dynamically depends on the concentration pulses. Messages are transferred along longer paths when received and decoded by means of dynamical emission response with respect to the ones encoded by absorbance scaling linearly with messenger concentration. These results represent a significant breakthrough in view of the futuristic development of a nonspecific molecular communication platform to encode and transfer information in multiple fluid environments, ranging from physiological to industrial ones.

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