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1.
Cell Commun Signal ; 22(1): 165, 2024 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448982

RESUMEN

BACKGROUND: Among the mechanisms of mitochondrial quality control (MQC), generation of mitochondria-derived vesicles (MDVs) is a process to avoid complete failure of mitochondria determining lysosomal degradation of mitochondrial damaged proteins. In this context, RAB7, a late endocytic small GTPase, controls delivery of MDVs to late endosomes for subsequent lysosomal degradation. We previously demonstrated that RAB7 has a pivotal role in response to cisplatin (CDDP) regulating resistance to the drug by extracellular vesicle (EVs) secretion. METHODS: Western blot and immunofluorescence analysis were used to analyze structure and function of endosomes and lysosomes in CDDP chemosensitive and chemoresistant ovarian cancer cell lines. EVs were purified from chemosensitive and chemoresistant cells by ultracentrifugation or immunoisolation to analyze their mitochondrial DNA and protein content. Treatment with cyanide m-chlorophenylhydrazone (CCCP) and RAB7 modulation were used, respectively, to understand the role of mitochondrial and late endosomal/lysosomal alterations on MDV secretion. Using conditioned media from chemoresistant cells the effect of MDVs on the viability after CDDP treatment was determined. Seahorse assays and immunofluorescence analysis were used to study the biochemical role of MDVs and the uptake and intracellular localization of MDVs, respectively. RESULTS: We observed that CDDP-chemoresistant cells are characterized by increased MDV secretion, impairment of late endocytic traffic, RAB7 downregulation, an increase of RAB7 in EVs, compared to chemosensitive cells, and downregulation of the TFEB-mTOR pathway overseeing lysosomal and mitochondrial biogenesis and turnover. We established that MDVs can be secreted rather than delivered to lysosomes and are able to deliver CDDP outside the cells. We showed increased secretion of MDVs by chemoresistant cells ultimately caused by the extrusion of RAB7 in EVs, resulting in a dramatic drop in its intracellular content, as a novel mechanism to regulate RAB7 levels. We demonstrated that MDVs purified from chemoresistant cells induce chemoresistance in RAB7-modulated process, and, after uptake from recipient cells, MDVs localize to mitochondria and slow down mitochondrial activity. CONCLUSIONS: Dysfunctional MQC in chemoresistant cells determines a block in lysosomal degradation of MDVs and their consequent secretion, suggesting that MQC is not able to eliminate damaged mitochondria whose components are secreted becoming effectors and potential markers of chemoresistance.


Asunto(s)
Resistencia a Antineoplásicos , Neoplasias Ováricas , Femenino , Humanos , Lisosomas , Neoplasias Ováricas/tratamiento farmacológico , Mitocondrias , Cisplatino/farmacología
2.
Molecules ; 28(19)2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37836603

RESUMEN

The therapeutic advantages of some platinum complexes as major anticancer chemotherapeutic agents and of nucleoside analogue-based compounds as essential antiviral/antitumor drugs are widely recognized. Red blood cells (RBCs) offer a potential new strategy for the targeted release of therapeutic agents due to their biocompatibility, which can protect loaded drugs from inactivation in the blood, thus improving biodistribution. In this study, we evaluated the feasibility of loading model nucleobase-containing Pt(II) complexes into human RBCs that were highly stabilized by four N-donors and susceptible to further modification for possible antitumor/antiviral applications. Specifically, platinum-based nucleoside derivatives [PtII(dien)(N7-Guo)]2+, [PtII(dien)(N7-dGuo)]2+, and [PtII(dien)(N7-dGTP)] (dien = diethylenetriamine; Guo = guanosine; dGuo = 2'-deoxy-guanosine; dGTP = 5'-(2'-deoxy)-guanosine-triphosphate) were investigated. These Pt(II) complexes were demonstrated to be stable species suitable for incorporation into RBCs. This result opens avenues for the possible incorporation of other metalated nucleobases analogues, with potential antitumor and/or antiviral activity, into RBCs.


Asunto(s)
Antineoplásicos , Compuestos Organoplatinos , Humanos , Compuestos Organoplatinos/farmacología , Compuestos Organoplatinos/metabolismo , Distribución Tisular , Platino (Metal) , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Antivirales/farmacología , Eritrocitos/metabolismo , Guanosina/metabolismo
3.
Molecules ; 26(10)2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-34068079

RESUMEN

Noble metals nanoparticles (NPs) and metal oxide NPs are widely used in different fields of application and commercial products, exposing living organisms to their potential adverse effects. Recent evidences suggest their presence in the aquifers water and consequently in drinking water. In this work, we have carefully synthesized four types of NPs, namely, silver and gold NPs (Ag NPs and Au NPs) and silica and titanium dioxide NPs (SiO2 NPs and TiO2 NPs) having a similar size and negatively charged surfaces. The synthesis of Ag NPs and Au NPs was carried out by colloidal route using silver nitrate (AgNO3) and tetrachloroauric (III) acid (HAuCl4) while SiO2 NPs and TiO2 NPs were achieved by ternary microemulsion and sol-gel routes, respectively. Once the characterization of NPs was carried out in order to assess their physico-chemical properties, their impact on living cells was studied. We used the human colorectal adenocarcinoma cells (Caco-2), known as the best representative intestinal epithelial barrier model to understand the effects triggered by NPs through ingestion. Then, we moved to explore how water contamination caused by NPs can be lowered by the ability of three species of aquatic moss, namely, Leptodictyum riparium, Vesicularia ferriei, and Taxiphyllum barbieri, to absorb them. The experiments were conducted using two concentrations of NPs (100 µM and 500 Μm as metal content) and two time points (24 h and 48 h), showing a capture rate dependent on the moss species and NPs type. Then, the selected moss species, able to actively capture NPs, appear as a powerful tool capable to purify water from nanostructured materials, and then, to reduce the toxicity associated to the ingestion of contaminated drinking water.


Asunto(s)
Absorción Fisicoquímica , Organismos Acuáticos/metabolismo , Briófitas/metabolismo , Fenómenos Químicos , Compuestos Inorgánicos/química , Mucosa Intestinal/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Modelos Biológicos , Organismos Acuáticos/efectos de los fármacos , Briófitas/efectos de los fármacos , Células CACO-2 , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dispersión Dinámica de Luz , Células Germinativas de las Plantas/efectos de los fármacos , Humanos , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Espectrofotometría Ultravioleta , Electricidad Estática , Titanio/química , Titanio/toxicidad , Difracción de Rayos X
4.
Sensors (Basel) ; 20(19)2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-32992867

RESUMEN

In the last decades, the increase in global industrialization and the consequent technological progress have damaged the quality of the environment. As a consequence, the high levels of hazardous compounds such as metals and gases released in the atmosphere and water, have raised several concerns about the health of living organisms. Today, many analytical techniques are available with the aim to detect pollutant chemical species. However, a lot of them are not affordable due to the expensive instrumentations, time-consuming processes and high reagents volumes. Last but not least, their use is exclusive to trained operators. Contrarily, colorimetric sensing devices, including paper-based devices, are easy to use, providing results in a short time, without particular specializations to interpret the results. In addition, the colorimetric response is suitable for fast detection, especially in resource-limited environments or underdeveloped countries. Among different chemical species, transition and heavy metals such as iron Fe(II) and copper Cu(II) as well as volatile compounds, such as ammonia (NH3) and acetaldehyde (C2H4O) are widespread mainly in industrialized geographical areas. In this work, we developed a colorimetric paper-based analytical device (PAD) to detect different contaminants, including Fe2+ and Cu2+ ions in water, and NH3 and C2H4O in air at low concentrations. This study is a "proof of concept" of a new paper sensor in which the intensity of the colorimetric response is proportional to the concentration of a detected pollutant species. The sensor model could be further implemented in other technologies, such as drones, individual protection devices or wearable apparatus to monitor the exposure to toxic species in both indoor and outdoor environments.

5.
Int J Mol Sci ; 20(14)2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31340471

RESUMEN

The side effects induced by nanoparticle exposure at a cellular level are one of the priority research topics due to the steady increase in the use of nanoparticles (NPs). Recently, the focus on cellular morphology and mechanical behavior is gaining relevance in order to fully understand the cytotoxic mechanisms. In this regard, we have evaluated the morphomechanical alteration in human breast adenocarcinoma cell line (MCF-7) exposed to TiO2NPs at two different concentrations (25 and 50 µg/mL) and two time points (24 and 48 h). By using confocal and atomic force microscopy, we demonstrated that TiO2NP exposure induces significant alterations in cellular membrane elasticity, due to actin proteins rearrangement in cytoskeleton, as calculated in correspondence to nuclear and cytoplasmic compartments. In this work, we have emphasized the alteration in mechanical properties of the cellular membrane, induced by nanoparticle exposure.


Asunto(s)
Núcleo Celular/efectos de los fármacos , Citosol/efectos de los fármacos , Citotoxinas/toxicidad , Nanopartículas/toxicidad , Titanio/toxicidad , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/ultraestructura , Fenómenos Biomecánicos , Membrana Celular/efectos de los fármacos , Núcleo Celular/ultraestructura , Supervivencia Celular/efectos de los fármacos , Citosol/ultraestructura , Citotoxinas/química , Elasticidad/efectos de los fármacos , Humanos , Células MCF-7 , Microscopía de Fuerza Atómica , Nanopartículas/ultraestructura , Titanio/química
6.
Int J Mol Sci ; 20(19)2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31546661

RESUMEN

The widespread use of nanoparticles (NPs) in medical devices has opened a new scenario in the treatment and prevention of many diseases and infections owing to unique physico-chemical properties of NPs. In this way, silver nanoparticles (AgNPs) are known to have a strong antimicrobial activity, even at low concentrations, due to their ability to selectively destroy cellular membranes. In particular, in the field of dental medicine, the use of AgNPs in different kinds of dental prosthesis matrixes could be a fundamental tool in immunodepressed patients that suffer of different oral infections. Candida albicans (C. albicans), an opportunistic pathogenic yeast with high colonization ability, is one of the causative agents of oral cavity infection. In our work, we added monodispersed citrate-capping AgNPs with a size of 20 nm at two concentrations (3 wt% and 3.5 wt%) in poly(methyl methacrylate) (PMMA), the common resin used to develop dental prostheses. After AgNPs characterization, we evaluated the topographical modification of PMMA and PMMA with the addition of AgNPs by means of atomic force microscopy (AFM), showing the reduction of surface roughness. The C. albicans colonization on PMMA surfaces was assessed by the Miles and Misra technique as well as by scanning electron microscopy (SEM) at 24 h and 48 h with encouraging results on the reduction of yeast viability after AgNPs exposure.


Asunto(s)
Antifúngicos/farmacología , Prótesis Dental/microbiología , Nanopartículas del Metal/química , Polimetil Metacrilato/química , Plata/farmacología , Antifúngicos/química , Candida albicans/efectos de los fármacos , Candida albicans/ultraestructura , Humanos , Nanopartículas del Metal/ultraestructura , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Plata/química
7.
Molecules ; 24(11)2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31141939

RESUMEN

Lauric acid is a green derivate that is abundant in some seeds such as coconut oil where it represents the most relevant fatty acid. Some studies have emphasized its anticancer effect due to apoptosis induction. In addition, the lauric acid is a Phase Change Material having a melting temperature of about 43.2 °C: this property makes it a powerful tool in cancer treatment by hyperthermal stress, generally induced at 43 °C. However, the direct use of lauric acid can have some controversial effects, and it can undergo degradation phenomena in the extracellular environment. For this reason, we have encapsulated lauric acid in a silica shell with a one-step and reproducible synthetic route in order to obtain a monodispersed SiO2@LA NPs with a good encapsulation efficiency. We have used these NPs to expose breast cancer cell lines (MCF-7) at different concentrations in combination with hyperthermal treatment. Uptake, viability, oxidative stress induction, caspases levels, and morphometric parameters were analyzed. These nanovectors showed double action in anticancer treatments thanks to the synergic effect of temperature and lauric acid activity.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Composición de Medicamentos , Ácidos Láuricos/uso terapéutico , Dióxido de Silicio/química , Temperatura , Actinas/metabolismo , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Rastreo Diferencial de Calorimetría , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Dispersión Dinámica de Luz , Femenino , Humanos , Ácidos Láuricos/farmacología , Células MCF-7 , Nanopartículas/química , Nanopartículas/ultraestructura , Especies Reactivas de Oxígeno/metabolismo , Espectrometría por Rayos X
8.
Anal Chem ; 90(12): 7659-7665, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29766712

RESUMEN

Functional, flexible, and integrated lab-on-chips, based on elastic membranes, are capable of fine response to external stimuli, so to pave the way for many applications as multiplexed sensors for a wide range of chemical, physical and biomedical processes. Here, we report on the use of elastic thin membranes (TMs), integrated with a reaction chamber, to fabricate a membrane-based pressure sensor (MePS) for reaction monitoring. In particular, the TM becomes the key-element in the design of a highly sensitive MePS capable to monitor gaseous species production in dynamic and temporally fast processes with high resolution and reproducibility. Indeed, we demonstrate the use of a functional MePS integrating a 2 µm thick polydimethylsiloxane TM by monitoring the dioxygen evolution resulting from catalytic hydrogen peroxide dismutation. The operation of the membrane, explained using a diffusion-dominated model, is demonstrated on two similar catalytic systems with catalase-like activity, assembled into polyelectrolyte multilayers capsules. The MePS, tested in a range between 2 and 50 Pa, allows detecting a dioxygen variation of the µmol L-1 s-1 order. Due to their structural features, flexibility of integration, and biocompatibility, the MePSs are amenable of future development within advanced lab-on-chips.

9.
Biomacromolecules ; 19(8): 3560-3571, 2018 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-30008208

RESUMEN

Alginate (ALG) and chitosan (CS) have been extensively used for biomedical applications; however, data relative to immune responses exerted by them are scarce. We synthesized a submicron vesicle system (SV) displaying a CS shell over an ALG core. Intravenous injection of these promising carriers could be a possible route of delivery; therefore, we evaluated their impact on human peripheral blood mononuclear cells (PBMCs). By this ex vivo approach, we established how SV chemical-physical characteristics affected the immune cells in terms of cellular uptake, viability, and state of activation. By flow cytometry, we demonstrated that SVs were internalized by PBMCs with differential trends. No substantial necrotic and apoptotic signals were recorded, and SVs weakly affected activation status of PBMCs (concerning the markers CD69, CD25, CD80, and the cytokines TNF-α and IL-6), showing high immune biocompatibility and low immunomodulating properties. Our findings gain particular value toward the biomedical applications of SVs and make these polymer-based structures more attractive for translation into clinical uses.


Asunto(s)
Alginatos/química , Quitosano/análogos & derivados , Monocitos/efectos de los fármacos , Nanopartículas/efectos adversos , Adulto , Antígenos CD/inmunología , Apoptosis , Células Cultivadas , Quitosano/inmunología , Humanos , Interleucina-6/inmunología , Persona de Mediana Edad , Monocitos/inmunología , Nanopartículas/química , Factor de Necrosis Tumoral alfa/inmunología
10.
Exp Cell Res ; 360(2): 303-309, 2017 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-28935466

RESUMEN

The EMT phenomenon is based on tumour progression. The cells lose their physiologic phenotype and assumed a mesenchymal phenotype characterized by an increased migratory capacity, invasiveness and high resistance to apoptosis. In this process, RHO family regulates the activation or suppression of ROCK (Rho-associated coiled-coil containing protein kinase) which in turn regulates the cytoskeleton dynamics. However, while the biochemical mechanisms are widely investigated, a comprehensive and careful estimation of biomechanical changes has not been extensively addressed. In this work, we used a strong ROCK inhibitor, Y-27632, to evaluate the effects of inhibition on living breast cancer epithelial cells by a biomechanical approach. Atomic Force Microscopy (AFM) was used to estimate changes of cellular elasticity, quantified by Young's modulus parameter. The morphometric alterations were analyzed by AFM topographies and Confocal Laser Scanning Microscopy (CLSM). Our study revealed a significant modification in the Young's modulus after treatment, especially as regards cytoskeletal region. Our evidences suggest that the use of Y-27632 enhanced the cell rigidity, preventing cell migration and arrested the metastasization process representing a potential powerful factor for cancer treatment.


Asunto(s)
Amidas/farmacología , Neoplasias de la Mama/patología , Neoplasias de la Mama/ultraestructura , Forma de la Célula/efectos de los fármacos , Piridinas/farmacología , Quinasas Asociadas a rho/antagonistas & inhibidores , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Citoesqueleto/ultraestructura , Módulo de Elasticidad/efectos de los fármacos , Elasticidad/efectos de los fármacos , Femenino , Humanos , Células MCF-7 , Microscopía de Fuerza Atómica , Estrés Mecánico , Células Tumorales Cultivadas
11.
Adv Exp Med Biol ; 1048: 1-19, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29453529

RESUMEN

The wide use of engineered nanomaterials in many fields, ranging from biomedical, agriculture, environment, cosmetic, urged the scientific community to understand the processes behind their potential toxicity, in order to develop new strategies for human safety. As a matter of fact, there is a big discrepancy between the increased classes of nanoparticles and the consequent applications versus their toxicity assessment. Nanotoxicology is defined as the science that studies the effects of engineered nanodevices and nanostructures in living organisms. This chapter analyzes the physico-chemical properties of the most used nanoparticles, the way they enter the living organism and their cytoxicity mechanisms at cellular exposure level. Moreover, the current state of nanoparticles risk assessment is reported and analyzed.


Asunto(s)
Nanopartículas/química , Nanopartículas/toxicidad , Seguridad , Animales , Humanos
12.
Int J Mol Sci ; 19(3)2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29509706

RESUMEN

LY2157299 (LY), which is very small molecule bringing high cancer diffusion, is a pathway antagonist against TGFß. LY dosage can be diluted by blood plasma, can be captured by immune system or it might be dissolved during digestion in gastrointestinal tract. The aim of our study is to optimize a "nano-elastic" carrier to avoid acidic pH of gastrointestinal tract, colon alkaline pH, and anti-immune recognition. Polygalacturonic acid (PgA) is not degradable in the gastrointestinal tract due to its insolubility at acidic pH. To avoid PgA solubility in the colon, we have designed its conjugation with Polyacrylic acid (PAA). PgA-PAA conjugation has enhanced their potential use for oral and injected dosage. Following these pre-requisites, novel polymeric nano-micelles derived from PgA-PAA conjugation and loading LY2157299 are developed and characterized. Efficacy, uptake and targeting against a hepatocellular carcinoma cell line (HLF) have also been demonstrated.


Asunto(s)
Antineoplásicos/farmacología , Hepatocitos/metabolismo , Micelas , Nanopartículas/química , Pirazoles/farmacología , Quinolinas/farmacología , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Hepatocitos/efectos de los fármacos , Humanos , Nanopartículas/metabolismo , Pirazoles/administración & dosificación , Quinolinas/administración & dosificación
13.
J Mater Sci Mater Med ; 28(8): 120, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28685231

RESUMEN

TGFß1 pathway antagonists have been considered promising therapies to attenuate TGFß downstream signals in cancer cells. Inhibiting peptides, as P-17 in this study, are bound to either TGFß1 or its receptors, blocking signal transduction. However, for efficient use of these TGFß1antagonist as target therapeutic tools, improvement in their delivery is required. Here, a plasmid carrying specific shDNA (SHT-DNA), small interfering RNA (siRNA), and the peptide (P-17) were loaded separately into folic acid (FA)-functionalized nano-carriers made of Bovine Serum Albumin (BSA). The two building blocks of the carrier, (BSA and FA) were used because of the high affinity of albumin for liver and for the overexpression of folate receptors on the membrane of hepatocellular carcinoma cells. The empty and the encapsulated carriers were thoroughly investigated to characterize their structure, to evaluate the colloidal stability and the surface functionalization. The entrapment of SHT-DNA, siRNA and P-17, respectively, was demonstrated by morphological and quantitative analysis. Finally, cellular studies were performed to assess the targeting efficiency of the hybrid carriers. These vectors were used because of the high affinity of albumin for liver and for the overexpression of folate receptors on the membrane hepatocellular carcinoma cells. The empty and the encapsulated carriers were thoroughly investigated to characterize their structure, to evaluate the colloidal stability and the surface functionalization. The entrapment of SHT-DNA, siRNA and P-17, respectively, was demonstrated by morphological and quantitative analysis. A novel fabrication of Hybrid Polymeric-Protein Nano-Carriers (HPPNC) for delivering TGF ß1 inhibitors to HCC cells has been developed. SHT-DNA, siRNA and P-17 have been successfully encapsulated. TGF ß1 inhibitors-loaded HPPNC were efficiently uptaken by HLF cells.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Portadores de Fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Polímeros/química , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Animales , Bovinos , Coloides/química , Sistemas de Liberación de Medicamentos , Receptores de Folato Anclados a GPI/metabolismo , Ácido Fólico/química , Humanos , Microscopía de Fuerza Atómica , Microscopía Fluorescente , Péptidos/química , ARN Interferente Pequeño/metabolismo , Albúmina Sérica Bovina , Espectroscopía Infrarroja por Transformada de Fourier
14.
Small ; 11(48): 6417-24, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26539625

RESUMEN

A fundamental issue in biomedical and environmental sciences is the development of sensitive and robust sensors able to probe the analyte of interest, under physiological and pathological conditions or in environmental samples, and with very high spatial resolution. In this work, novel hybrid organic fibers that can effectively report the analyte concentration within the local microenvironment are reported. The nanostructured and flexible wires are prepared by embedding fluorescent pH sensors based on seminaphtho-rhodafluor-1-dextran conjugate. By adjusting capsule/polymer ratio and spinning conditions, the diameter of the fibers and the alignment of the reporting capsules are both tuned. The hybrid wires display excellent stability, high sensitivity, as well as reversible response, and their operation relies on effective diffusional kinetic coupling of the sensing regions and the embedding polymer matrix. These devices are believed to be a powerful new sensing platform for clinical diagnostics, bioassays and environmental monitoring.


Asunto(s)
Nanofibras/química , Nanotecnología/métodos , Compuestos Orgánicos/química , Concentración de Iones de Hidrógeno , Iones , Microscopía Confocal , Nanofibras/ultraestructura , Factores de Tiempo
15.
Small ; 11(48): 6416, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26768351

RESUMEN

On page 6417, L. L. del Mercato, D. Pisignano, and co-workers report a new type of 3D nanostructured pH-sensing organic fiber with embedded ratiometric fluorescent capsules. Upon proton-induced switching, the fibers undergo optical changes that are recorded by fluorescence detectors and correlated to the analyte concentration. The developed electrospinning fabrication approach is facile and versatile and enables the creation of sensitive and highly robust pH-sensing 3D scaffolds for environmental monitoring and biomedical applications, including tissue engineering and wound healing.


Asunto(s)
Nanofibras/química , Nanotecnología/métodos , Concentración de Iones de Hidrógeno , Iones , Protones , Ingeniería de Tejidos , Andamios del Tejido/química
16.
Chemistry ; 20(35): 10910-4, 2014 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-24920540

RESUMEN

Multicompartment, spherical microcontainers were engineered through a layer-by-layer polyelectrolyte deposition around a fluorescent core while integrating a ruthenium polyoxometalate (Ru4POM), as molecular motor, vis-à-vis its oxygenic, propeller effect, fuelled upon H2O2 decomposition. The resulting chemomechanical system, with average speeds of up to 25 µm s(-1), is amenable for integration into a microfluidic set-up for mixing and displacement of liquids, whereby the propulsion force and the resulting velocity regime can be modulated upon H2O2-controlled addition.

17.
Ibrain ; 10(2): 123-133, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915951

RESUMEN

Neurodegenerative diseases represent an increasingly burdensome challenge of the past decade, primarily driven by the global aging of the population. Ongoing efforts focus on implementing diverse strategies to mitigate the adverse effects of neurodegeneration, with the goal of decelerating the pathology progression. Notably, in recent years, it has emerged that the use of nanoparticles (NPs), particularly those obtained through green chemical processes, could constitute a promising therapeutic approach. Green NPs, exclusively sourced from phytochemicals, are deemed safer compared to NPs synthetized through conventional chemical route. In this study, the effects of green chemistry-derived silver NPs (AgNPs) were assessed in neuroblastoma cells, SHSY-5Y, which are considered a pivotal model for investigating neurodegenerative diseases. Specifically, we used two different concentrations (0.5 and 1 µM) of AgNPs and two time points (24 and 48 h) to evaluate the impact on neuroblastoma cells by observing viability reduction and intracellular calcium production, especially using 1 µM at 48 h. Furthermore, investigation using atomic force microscopy (AFM) unveiled an alteration in Young's modulus due to the reorganization of cortical actin following exposure to green AgNPs. This evidence was further corroborated by confocal microscopy acquisitions as well as coherency and density analyses on actin fibers. Our in vitro findings suggest the potential efficacy of green AgNPs against neurodegeneration; therefore, further in vivo studies are imperative to optimize possible therapeutic protocols.

18.
RSC Adv ; 14(20): 14126-14138, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38686287

RESUMEN

Magnetic nanocomposites (MNC) are promising theranostic platforms with tunable physicochemical properties allowing for remote drug delivery and multimodal imaging. Here, we developed doxorubicin-loaded Fe3O4-Au MNC (DOX-MNC) using electron beam physical vapor deposition (EB-PVD) in combination with magneto-mechanochemical synthesis to assess their antitumor effect on Walker-256 carcinosarcoma under the influence of a constant magnetic (CMF) and electromagnetic field (EMF) by comparing tumor growth kinetics, magnetic resonance imaging (MRI) scans and electron spin resonance (ESR) spectra. Transmission (TEM) and scanning electron microscopy (SEM) confirmed the formation of spherical magnetite nanoparticles with a discontinuous gold coating that did not significantly affect the ferromagnetic properties of MNC, as measured by vibrating-sample magnetometry (VSM). Tumor-bearing animals were divided into the control (no treatment), conventional doxorubicin (DOX), DOX-MNC and DOX-MNC + CMF + EMF groups. DOX-MNC + CMF + EMF resulted in 14% and 16% inhibition of tumor growth kinetics as compared with DOX and DOX-MNC, respectively. MRI visualization showed more substantial tumor necrotic changes after the combined treatment. Quantitative analysis of T2-weighted (T2W) images revealed the lowest value of skewness and a significant increase in tumor intensity in response to DOX-MNC + CMF + EMF as compared with the control (1.4 times), DOX (1.6 times) and DOX-MNC (1.8 times) groups. In addition, the lowest level of nitric oxide determined by ESR was found in DOX-MNC + CMF + EMF tumors, which was close to that of the muscle tissue in the contralateral limb. We propose that the reason for the relationship between the observed changes in MRI and ESR is the hyperfine interaction of nuclear and electron spins in mitochondria, as a source of free radical production. Therefore, these results point to the use of EB-PVD and magneto-mechanochemically synthesized Fe3O4-Au MNC loaded with DOX as a potential candidate for cancer magnetic nanotheranostic applications.

19.
Pharmaceutics ; 15(2)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36839822

RESUMEN

The conventional methods of cancer treatment and diagnosis, such as radiotherapy, chemotherapy, and computed tomography, have developed a great deal. However, the effectiveness of such methods is limited to the possible failure or collateral effects on the patients. In recent years, nanoscale materials have been studied in the field of medical physics to develop increasingly efficient methods to treat diseases. Gold nanoparticles (AuNPs), thanks to their unique physicochemical and optical properties, were introduced to medicine to promote highly effective treatments. Several studies have confirmed the advantages of AuNPs such as their biocompatibility and the possibility to tune their shapes and sizes or modify their surfaces using different chemical compounds. In this review, the main properties of AuNPs are analyzed, with particular focus on star-shaped AuNPs. In addition, the main methods of tumor treatment and diagnosis involving AuNPs are reviewed.

20.
Nanomaterials (Basel) ; 13(19)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37836360

RESUMEN

Radiotherapy (RT) involves delivering X-ray beams to the tumor site to trigger DNA damage. In this approach, it is fundamental to preserve healthy cells and to confine the X-ray beam only to the malignant cells. The integration of gold nanoparticles (AuNPs) in the X-ray methodology could be considered a powerful tool to improve the efficacy of RT. Indeed, AuNPs have proven to be excellent allies in contrasting tumor pathology upon RT due to their high photoelectric absorption coefficient and unique physiochemical properties. However, an analysis of their physical and morphological reaction to X-ray exposure is necessary to fully understand the AuNPs' behavior upon irradiation before treating the cells, since there are currently no studies on the evaluation of potential NP morphological changes upon specific irradiations. In this work, we synthesized two differently shaped AuNPs adopting two different techniques to achieve either spherical or star-shaped AuNPs. The spherical AuNPs were obtained with the Turkevich-Frens method, while the star-shaped AuNPs (AuNSs) involved a seed-mediated approach. We then characterized all AuNPs with Transmission Electron Microscopy (TEM), Uv-Vis spectroscopy, Dynamic Light Scattering (DLS), zeta potential and Fourier Transform Infrared (FTIR) spectroscopy. The next step involved the treatment of AuNPs with two different doses of X-radiation commonly used in RT, namely 1.8 Gy and 2 Gy, respectively. Following the X-rays' exposure, the AuNPs were further characterized to investigate their possible physicochemical and morphological alterations induced with the X-rays. We found that AuNPs do not undergo any alteration, concluding that they can be safely used in RT treatments. Lastly, the actin rearrangements of THP-1 monocytes treated with AuNPs were also assessed in terms of coherency. This is a key proof to evaluate the possible activation of an immune response, which still represents a big limitation for the clinical translation of NPs.

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