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1.
Bioelectron Med ; 9(1): 28, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38053220

RESUMEN

The increasing prevalence of chronic diseases is a driver for emerging big data technologies for healthcare including digital platforms for data collection, systems for active patient engagement and education, therapy specific predictive models, optimized patient pathway models. Powerful bioelectronic medicine tools for data collection, analysis and visualization allow for joint processing of large volumes of heterogeneous data, which in turn can produce new insights about patient outcomes and alternative interpretations of clinical patterns that can lead to implementation of optimized clinical decisions and clinical patient pathway by healthcare professionals.With this perspective, we identify innovative solutions for disease management and evaluate their impact on patients, payers and society, by analyzing their impact in terms of clinical outcomes (effectiveness, safety, and quality of life) and economic outcomes (cost-effectiveness, savings, and productivity).As a result, we propose a new approach based on the main pillars of innovation in the disease management area, i.e. progressive patient care models, patient-centric approaches, bioelectronics for precise medicine, and lean management that, combined with an increase in appropriate private-public-citizen-partnership, leads towards Patient-Centric Healthcare.

2.
Int J Pharm ; 647: 123489, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-37805150

RESUMEN

Fungal infections of the skin, nails, and hair are a common health concern affecting a significant proportion of the population worldwide. The current treatment options include topical and systematic agents which have low permeability and prolonged treatment period, respectively. Consequently, there is a growing need for a permeable, effective, and safe treatment. Keratin nanoparticles are a promising nanoformulation that can improve antifungal agent penetration, providing sustainable targeted drug delivery. In this study, keratin nanoparticles were prepared using a custom-made 3D-printed microfluidic chip and the manufacturing process was optimized using the design of experiments (DoE) approach. The total flow rate (TFR), flow rate ratio (FRR), and keratin concentration were found to be the most influential factors of the size and polydispersity index (PDI) of the nanoparticles. The crosslinking procedure by means of tannic acid as safe and biocompatible compound was also optimized. Keratin nanoparticles loaded with a different amount of tioconazole showed a size lower than 200 nm, a PDI lower than 0.2 and an encapsulation efficiency of 91 ± 1.9 %. Due to their sustained drug release, the formulations showed acceptable in vitro biocompatibility. Furthermore, a significant inhibitory effect compared to the free drug against Microsporum canis.


Asunto(s)
Microfluídica , Nanopartículas , Microfluídica/métodos , Queratinas , Sistemas de Liberación de Medicamentos/métodos , Imidazoles , Tamaño de la Partícula
3.
Nanomaterials (Basel) ; 13(14)2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37513040

RESUMEN

Hydrotalcites (HTlcs) are a class of nanostructured layered materials that may be employed in a variety of applications, from green to bio technologies. In this paper, we report an investigation on HTlcs made of Mg and Fe, recently employed to improve the growth in vitro of osteoblasts within a keratin sponge. We carried out an analysis of powder materials and of HTlcs dispersed in keratin and spin-coated on a Si/SiO2 substrate at different temperatures. A magnetic study of the powders was carried out with a Quantum Design Physical Property Measurement System equipped with a Vibrating Sample Magnetometer. The data gathered prove that these HTlcs are fully paramagnetic, and keratin showed a very small magnetic response. Optical and Atomic Force Microscopy analyses of the thin films provide a detailed picture of clusters randomly dispersed in the films with various dimensions. The magnetic properties of these films were characterized using the Nano Magneto Optical Kerr Effect (NanoMOKE) down to 7.5 K. The data collected show that the local magnetic properties can be mapped with a micrometric resolution distinguishing HTlc regions from keratin ones. This approach opens new perspectives in the characterization of these composite materials.

4.
Pharmacol Ther ; 245: 108403, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37024060

RESUMEN

Interoception is the process by which the nervous system regulates internal functions to achieve homeostasis. The role of neurons in interoception has received considerable recent attention, but glial cells also contribute. Glial cells can sense and transduce signals including osmotic, chemical, and mechanical status of extracellular milieu. Their ability to dynamically communicate "listening" and "talking" to neurons is necessary to monitor and regulate homeostasis and information integration in the nervous system. This review introduces the concept of "Glioception" and focuses on the process by which glial cells sense, interpret and integrate information about the inner state of the organism. Glial cells are ideally positioned to act as sensors and integrators of diverse interoceptive signals and can trigger regulatory responses via modulation of the activity of neuronal networks, both in physiological and pathological conditions. We believe that understanding and manipulating glioceptive processes and underlying molecular mechanisms provide a key path to develop new therapies for the prevention and alleviation of devastating interoceptive dysfunctions, among which pain is emphasized here with more focused details.


Asunto(s)
Interocepción , Humanos , Interocepción/fisiología , Neuroglía , Neuronas/fisiología , Dolor
5.
Foods ; 12(6)2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36981100

RESUMEN

In this study the recycling of pomegranate peel powder (PPP) was proposed. In particular, the use of powder loaded in a silk fibroin polymeric matrix to create an active pad was tested. For the sake of comparison, the powder alone was also analysed. Both powder and active pad efficacy was assessed in two different food systems, soymilk (rich in proteins), preliminarily contaminated with Pseudomonas spp. and yeasts, and apple juice (rich in carbohydrates), preliminarily contaminated with Alyciclobacillus acidoterrestris. Three different concentrations of powder alone and powder in the pad were tested (5%, 7.5% and 10% w/v) in both types of beverages. To assess a possible dependence of the efficacy on the powder granulometry, different powder sizes were preliminarily analysed on Pseudomonas spp. and yeasts using an in vitro test. PPP was effective on both Pseudomonas spp. and yeasts. No significant differences appeared among the tested granulometries and therefore in the subsequent tests powder with an average diameter of 250 µm was used. Results recorded with soymilk and apple juice were different. When applied to the soymilk, the activity of PPP in the pad was less effective than that recorded when the powder was directly added to the beverage. With the two highest powder concentrations directly added to food, more than four log cycle reductions in Pseudomonas spp. and yeast cells were recorded, compared to soymilk without any powder. Compared to the control sample, all the soymilk samples either with PPP or with the active pad showed a delayed microbial and fungal growth. When applied to apple juice, both powder and pad were effective at completely inhibiting the proliferation of A. acidoterrestris (<102 CFU/g).

6.
Adv Biol (Weinh) ; 7(6): e2200269, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36709481

RESUMEN

Astrocytes are key regulators of brain homeostasis, equilibrating ion, water, and neurotransmitter concentrations and maintaining essential conditions for proper cognitive function. Recently, it has been shown that the excitability of the actin cytoskeleton manifests in second-scale dynamic fluctuations and acts as a sensor of chemophysical environmental cues. However, it is not known whether the cytoskeleton is excitable in astrocytes and how the homeostatic function of astrocytes is linked to the dynamics of the cytoskeleton. Here it is shown that homeostatic regulation involves the excitable dynamics of actin in certain subcellular regions of astrocytes, especially near the cell boundary. The results further indicate that actin dynamics concentrate into "hotspot" regions that selectively respond to certain chemophysical stimuli, specifically the homeostatic challenges of ion or water concentration increases. Substrate topography makes the actin dynamics of astrocytes weaker. Super-resolution images demonstrate that surface topography is also associated with the predominant perpendicular alignment of actin filaments near the cell boundary, whereas flat substrates result in an actin cortex mainly parallel to the cell boundary. Additionally, coculture with neurons increases both the probability of actin dynamics and the strength of hotspots. The excitable systems character of actin thus makes astrocytes direct participants in neural cell network dynamics.


Asunto(s)
Actinas , Astrocitos , Animales , Actinas/metabolismo , Astrocitos/metabolismo , Roedores/metabolismo , Células Cultivadas , Citoesqueleto/metabolismo
7.
Int J Mol Sci ; 23(12)2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35743248

RESUMEN

Skin disorders are widespread around the world, affecting people of all ages, and oxidative stress represents one of the main causes of alteration in the normal physiological parameters of skin cells. In this work, we combined a natural protein, fibroin, with antioxidant compounds extracted in water from pomegranate waste. We demonstrate the effective and facile fabrication of bioactive and eco-sustainable films of potential interest for skin repair. The blended films are visually transparent (around 90%); flexible; stable in physiological conditions and in the presence of trypsin for 12 days; able to release the bioactive compounds in a controlled manner; based on Fickian diffusion; and biocompatible towards the main skin cells, keratinocytes and fibroblasts. Furthermore, reactive oxygen species (ROS) production tests demonstrated the high capacity of our films to reduce the oxidative stress induced in cells, which is responsible for various skin diseases.


Asunto(s)
Fibroínas , Granada (Fruta) , Fibroblastos , Humanos , Queratinocitos , Seda
8.
Int J Pharm ; 623: 121888, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35716978

RESUMEN

In this work keratin/poly(lactic acid) (PLA) 50/50 wt blend nanofibers with different loadings of graphene-oxide (GO) were prepared by electrospinning and tested as delivery systems of Rhodamine Blue (RhB), selected as a model of a drug. The effect of GO on the electrospinnability and drug release mechanism and kinetics was investigated. Rheological measurements carried out on the blend solutions revealed unsatisfactory compatibility between keratin and PLA under quiet condition. Accordingly, poor interfacial adhesion between the two phases was observed by SEM analysis of a film prepared by solution casting. On the contrary, keratin chains seem to rearrange under the flux conditions of the electrospinning process thus promoting better interfacial interactions between the two polymers, thereby enhancing their miscibility, which resulted in homogeneous and defect-free nanofibers. The loading of GO into the keratin/PLA solution contributes to increase its viscosity, its shear thinning behavior, and its conductivity. Accordingly, thinner and more homogeneous nanofibers resulted from solutions with a relatively high conductivity coupled with a pronounced shear thinning behavior. FTIR and DSC analyses have underlined, that while the PLA/GO interfacial interactions significantly compete with the PLA/keratin ones, there are no significant effects of GO on the structural organization of keratin in blend with the PLA. However, GO offers several advantages from the application point of view by slightly improving the mechanical properties of the electrospun mats and by slowing down the release of the model drug through the reduction of the matrix swelling.


Asunto(s)
Grafito , Nanofibras , Grafito/química , Queratinas/química , Nanofibras/química , Poliésteres/química
9.
Nanomaterials (Basel) ; 12(9)2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35564115

RESUMEN

In recent years, several studies have focused their attention on the preparation of biocompatible and biodegradable nanocarriers of potential interest in the biomedical field, ranging from drug delivery systems to imaging and diagnosis. In this regard, natural biomolecules-such as proteins-represent an attractive alternative to synthetic polymers or inorganic materials, thanks to their numerous advantages, such as biocompatibility, biodegradability, and low immunogenicity. Among the most interesting proteins, keratin extracted from wool and feathers, as well as fibroin extracted from Bombyx mori cocoons, possess all of the abovementioned features required for biomedical applications. In the present review, we therefore aim to give an overview of the most important and efficient methodologies for obtaining drug-loaded keratin and fibroin nanoparticles, and of their potential for biomedical applications.

10.
Foods ; 10(12)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34945471

RESUMEN

In this study, a bio-based polymeric system loaded with fruit by-products was developed. It was based on silk fibroin produced by the silkworm Bombyx mori and pomegranate peel powder, selected as active agent. The weight ratio between fibroin and pomegranate powder was 30:70. Pads also contained 20% w/w of glycerol vs. fibroin to induce water insolubility. Control systems, consisting of only fibroin and glycerol, were produced as reference. Both control and active systems were characterized for structural and morphological characterization (Fourier-transform infrared spectroscopy and optical microscope), antioxidant properties and antimicrobial activity against two foodborne spoilage microorganisms. Results demonstrate that under investigated conditions, an active system was obtained. The pad showed a good water stability, with weight loss of about 28% due to the release of the active agent and not to the fibroin loss. In addition, this edible system has interesting antioxidant and antimicrobial properties. In particular, the pad based on fibroin with pomegranate peel recorded an antioxidant activity of the same order of magnitude of that of vitamin C, which is one of the most well-known antioxidant compounds. As regards the antimicrobial properties, results underlined that pomegranate peel in the pad allowed maintaining microbial concentration around the same initial level (104 CFU/mL) for more than 70 h of monitoring, compared to the control system where viable cell concentration increased very rapidly up to 108 CFU/mL.

11.
Cell Physiol Biochem ; 55(S1): 196-212, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34740285

RESUMEN

BACKGROUND/AIMS: The ability of astrocytes to control extracellular volume homeostasis is critical for brain function and pathology. Uncovering the mechanisms of cell volume regulation by astrocytes will be important for identifying novel therapeutic targets for neurological conditions, such as those characterized by imbalances to hydro saline challenges (as in edema) or by altered cell volume regulation (as in glioma). One major challenge in studying the astroglial membrane channels involved in volume homeostasis in cell culture model systems is that the expression patterns of these membrane channels do not resemble those observed in vivo. In our previous study, we demonstrated that rat primary astrocytes grown on nanostructured interfaces based on hydrotalcite-like compounds (HTlc) in vitro are differentiated and display molecular and functional properties of in vivo astrocytes, such as the functional expression of inwardly rectifying K+ channel (Kir 4.1) and Aquaporin-4 (AQP4) at the astrocytic microdomain. Here, we take advantage of the properties of differentiated primary astrocytes in vitro to provide an insight into the mechanism underpinning astrocytic cell volume regulation and its correlation with the expression and function of AQP4, Transient Receptor Potential Vanilloid 4(TRPV4), and Volume Regulated Anion Channel (VRAC). METHODS: The calcein quenching method was used to study water transport and cell volume regulation. Calcium imaging and electrophysiology (patch-clamp) were used for functional analyses of calcium dynamics and chloride currents. Western blot and immunofluorescence were used to analyse the expression and localization of the channel proteins of interest. RESULTS: We found that the increase in water permeability, previously observed in differentiated astrocytes, occurs simultaneously with more efficient regulatory volume increase and regulatory volume decrease. Accordingly, the magnitude of the hypotonic induced intracellular calcium response, typically mediated by TRPV4, as well as the hypotonic induced VRAC current, was almost twice as high in differentiated astrocytes. Interestingly, while we confirmed increased AQP4 expression in the membrane of differentiated astrocytes, the expression of the channels TRPV4 and Leucine-Rich Repeats-Containing 8-A (LRRC8-A) were comparable between differentiated and non-differentiated astrocytes. CONCLUSION: The reported results indicate that AQP4 up-regulation observed in differentiated astrocytes might promote higher sensitivity of the cell to osmotic changes, resulting in increased magnitude of calcium signaling and faster kinetics of the RVD and RVI processes. The implications for cell physiology and the mechanisms underlying astrocytic interaction with nanostructured interfaces are discussed.


Asunto(s)
Astrocitos/citología , Tamaño de la Célula , Animales , Acuaporina 4/metabolismo , Astrocitos/metabolismo , Células Cultivadas , Permeabilidad , Ratas Wistar , Canales Catiónicos TRPV/metabolismo , Agua/metabolismo
12.
Biomolecules ; 11(8)2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-34439860

RESUMEN

In recent years there has been a growing interest in the use of proteins as biocompatible and environmentally friendly biomolecules for the design of wound healing and drug delivery systems. Keratin is a fascinating protein, obtainable from several keratinous biomasses such as wool, hair or nails, with intrinsic bioactive properties including stimulatory effects on wound repair and excellent carrier capability. In this work keratin/poly(butylene succinate) blend solutions with functional properties tunable by manipulating the polymer blending ratios were prepared by using 1,1,1,3,3,3-hexafluoroisopropanol as common solvent. Afterwards, these solutions doped with rhodamine B (RhB), were electrospun into blend mats and the drug release mechanism and kinetics as a function of blend composition was studied, in order to understand the potential of such membranes as drug delivery systems. The electrophoresis analysis carried out on keratin revealed that the solvent used does not degrade the protein. Moreover, all the blend solutions showed a non-Newtonian behavior, among which the Keratin/PBS 70/30 and 30/70 ones showed an amplified orientation ability of the polymer chains when subjected to a shear stress. Therefore, the resulting nanofibers showed thinner mean diameters and narrower diameter distributions compared to the Keratin/PBS 50/50 blend solution. The thermal stability and the mechanical properties of the blend electrospun mats improved by increasing the PBS content. Finally, the RhB release rate increased by increasing the keratin content of the mats and the drug diffused as drug-protein complex.


Asunto(s)
Butileno Glicoles/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Diseño de Fármacos , Liberación de Fármacos , Queratinas/síntesis química , Nanofibras/química , Polímeros/síntesis química , Animales , Butileno Glicoles/farmacocinética , Queratinas/farmacocinética , Polímeros/farmacocinética
13.
Nanoscale ; 13(8): 4390-4407, 2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33599662

RESUMEN

Graphene nanosheets are mechanically strong but flexible, electrically conductive and bio-compatible. Thus, due to these unique properties, they are being intensively studied as materials for the next generation of neural interfaces. Most of the literature focused on optimizing the interface between these materials and neurons. However, one of the most common causes of implant failure is the adverse inflammatory reaction of glial cells. These cells are not, as previously considered, just passive and supportive cells, but play a crucial role in the physiology and pathology of the nervous system, and in the interaction with implanted electrodes. Besides providing structural support to neurons, glia are responsible for the modulation of synaptic transmission and control of central and peripheral homeostasis. Accordingly, knowledge on the interaction between glia and biomaterials is essential to develop new implant-based therapies for the treatment of neurological disorders, such as epilepsy, brain tumours, and Alzheimer's and Parkinson's disease. This work provides an overview of the emerging literature on the interaction of graphene-based materials with glial cells, together with a complete description of the different types of glial cells and problems associated with them. We believe that this description will be important for researchers working in materials science and nanotechnology to develop new active materials to interface, measure and stimulate these cells.


Asunto(s)
Grafito , Neuroglía , Neuronas , Transmisión Sináptica
14.
RSC Adv ; 11(19): 11347-11355, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35423613

RESUMEN

Recent studies have proposed that the bioelectrical response of glial cells, called astrocytes, currently represents a key target for neuroregenerative purposes. Here, we propose the fabrication of electrospun nanofibres containing gelatin and polyaniline (PANi) synthesized in the form of nano-needles (PnNs) as electrically conductive scaffolds to support the growth and functionalities of primary astrocytes. We report a fine control of the morphological features in terms of fibre size and spatial distribution and fibre patterning, i.e. random or aligned fibre organization, as revealed by SEM- and TEM-supported image analysis. We demonstrate that the peculiar morphological properties of fibres - i.e., the fibre size scale and alignment - drive the adhesion, proliferation, and functional properties of primary cortical astrocytes. In addition, the gradual transmission of biochemical and biophysical signals due to the presence of PnNs combined with the presence of gelatin results in a permissive and guiding environment for astrocytes. Accordingly, the functional properties of astrocytes measured via cell patch-clamp experiments reveal that PnNs do not alter the bioelectrical properties of resting astrocytes, thus setting the scene for the use of PnN-loaded nanofibres as bioconductive platforms for interfacing astrocytes and controlling their bioelectrical properties.

15.
Mater Sci Eng C Mater Biol Appl ; 118: 111363, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33254982

RESUMEN

Increasing evidences are demonstrating that structural and functional properties of non-neuronal brain cells, called astrocytes, such as those of cytoskeleton and of ion channels, are critical for brain physiology. Also, changes in astrocytes structure and function concur to and might determine the outcome of neuronal damage in acute neurological conditions or of chronic disease. Thus, the design and engineering of biomaterials that can drive the structural and functional properties of astrocytes is of growing interest for neuroregenerative medicine. Poly-ɛ-caprolactone (PCL), is FDA-approved polyester having excellent mechanical and chemical properties that can be tailored to obtain neural implants for regenerative purposes. However, the study on the use of PCL substrates for neuroregenerative purposes are mainly aimed at investigating the interaction of the material with neurons. Here, we report on the long-term viability, morphology, structural and functional properties of primary astrocytes grown on electrospun fibres of PCL (-GEL) and on blending of PCL and Gelatin protein (+GEL). We found that topography and morphological features of the substrate are the properties that mainly drives astrocytes adhesion and survival, over the long term, while they do not alter the cell function. Specifically, aligned PCL fibres induced in astrocytes a dramatic actin-cytoskeletal rearrangement as well as focal adhesion point number and distribution. Interestingly, structural changes observed in elongated astrocytes are not correlated with alterations in their electrophysiological properties. Our results indicated that PCL electrospun fibres are a permissive substrate that can be tuned to selectively alters astrocytes structural components while preserving astrocytes function. The results open the view for the use of PCL based electrospun fibres to target astrocytes for the treatment of brain dysfunction such as injuries or chronical disease.


Asunto(s)
Nanofibras , Astrocitos , Gelatina , Poliésteres , Ingeniería de Tejidos , Andamios del Tejido
16.
Adv Healthc Mater ; 10(1): e2001268, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33103375

RESUMEN

Research over the past four decades has highlighted the importance of certain brain cells, called glial cells, and has moved the neurocentric vision of structure, function, and pathology of the nervous system toward a more holistic perspective. In this view, the demand for technologies that are able to target and both selectively monitor and control glial cells is emerging as a challenge across neuroscience, engineering, chemistry, and material science. Frequently neglected or marginally considered as a barrier to be overcome between neural implants and neuronal targets, glial cells, and in particular astrocytes, are increasingly considered as active players in determining the outcomes of device implantation. This review provides a concise overview not only of the previously established but also of the emerging physiological and pathological roles of astrocytes. It also critically discusses the most recent advances in biomaterial interfaces and devices that interact with glial cells and thus have enabled scientists to reach unprecedented insights into the role of astroglial cells in brain function and dysfunction. This work proposes glial interfaces and glial engineering as multidisciplinary fields that have the potential to enable significant advancement of knowledge surrounding cognitive function and acute and chronic neuropathologies.


Asunto(s)
Astrocitos , Neuroglía , Encéfalo , Neuronas
17.
Adv Biosyst ; 4(4): e1900264, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32293156

RESUMEN

The correct human brain function is dependent on the activity of non-neuronal cells called astrocytes. The bioelectrical properties of astrocytes in vitro do not closely resemble those displayed in vivo and the former are incapable of generating action potential; thus, reliable approaches in vitro for noninvasive electrophysiological recording of astrocytes remain challenging for biomedical engineering. Here it is found that primary astrocytes grown on a device formed by a forest of randomly oriented gold coated-silicon nanowires, resembling the complex structural and functional phenotype expressed by astrocytes in vivo. The device enables noninvasive extracellular recording of the slow-frequency oscillations generated by differentiated astrocytes, while flat electrodes failed on recording signals from undifferentiated cells. Pathophysiological concentrations of extracellular potassium, occurring during epilepsy and spreading depression, modulate the power of slow oscillations generated by astrocytes. A reliable approach to study the role of astrocytes function in brain physiology and pathologies is presented.


Asunto(s)
Potenciales de Acción , Astrocitos/metabolismo , Relojes Biológicos , Diferenciación Celular , Nanocables/química , Silicio/química , Animales , Humanos , Cultivo Primario de Células , Ratas , Ratas Wistar
18.
Front Chem ; 8: 158, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32219091

RESUMEN

In this work we report the preparation and characterization of free-standing keratin-based films containing Au/Ag nanorods. The effect of nanorods surface chemistry on the optical and mechanical properties of keratin composite films is fully investigated. Colloid nanorods confer to the keratin films interesting color effects due to plasmonic absorptions of the metal nanostructures. The presence of metal NRs induces also substantial change in the protein fluorescence emission. In particular, the relative contribution of the ordered-protein aggregates emission is enhanced by the presence of cysteine and thus strictly related to the surface chemistry of nanorods. The presence of more packed supramolecular structures in the films containing metal nanorods (in particular cysteine modified ones) is confirmed by ATR measurements. In addition, the films containing nanorods show a higher Young's modulus compared to keratin alone and again the effect is more pronounced for cysteine modified nanorods. Collectively, the reported results indicate the optical and mechanical properties of keratin composites films are related to a common property and can be tuned simultaneously, paving the way to the optimization and improvement of their performances and enhancing the exploitation of keratin composites in highly technological optoelectronic applications.

19.
FASEB J ; 34(5): 6539-6553, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32202681

RESUMEN

Astrocytes are non-neuronal cells that govern the homeostatic regulation of the brain through ions and water transport, and Ca2+ -mediated signaling. As they are tightly integrated into neural networks, label-free tools that can modulate cell function are needed to evaluate the role of astrocytes in brain physiology and dysfunction. Using live-cell fluorescence imaging, pharmacology, electrophysiology, and genetic manipulation, we show that pulsed infrared light can modulate astrocyte function through changes in intracellular Ca2+ and water dynamics, providing unique mechanistic insight into the effect of pulsed infrared laser light on astroglial cells. Water transport is activated and, IP3 R, TRPA1, TRPV4, and Aquaporin-4 are all involved in shaping the dynamics of infrared pulse-evoked intracellular calcium signal. These results demonstrate that astrocyte function can be modulated with infrared light. We expect that targeted control over calcium dynamics and water transport will help to study the crucial role of astrocytes in edema, ischemia, glioma progression, stroke, and epilepsy.


Asunto(s)
Astrocitos/metabolismo , Calcio/metabolismo , Rayos Infrarrojos , Agua/metabolismo , Animales , Acuaporina 4/genética , Acuaporina 4/metabolismo , Astrocitos/citología , Astrocitos/efectos de la radiación , Transporte Biológico , Células Cultivadas , Homeostasis , Ratas , Transducción de Señal , Canal Catiónico TRPA1/genética , Canal Catiónico TRPA1/metabolismo , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo
20.
Artículo en Inglés | MEDLINE | ID: mdl-32154225

RESUMEN

In this work, keratin sponges were prepared by freeze-drying method and tested for adsorption of Azure A and Methyl Orange dyes. The obtained materials showed a porosity of 99.92% and a mean pore size dimension of about 91 µm. The use of oxidized sucrose with a heating treatment at 150°C was demonstrated to be a useful crosslinking procedure alternative to the conventional glutaraldehyde. Keratin sponges showed a maximum adsorption capacity of 0.063 and of 0.037 mmol/g for Azure A and Methyl Orange, respectively. The absorption of the cationic dye Azure A onto keratin sponges was better described by Freundlich model while the isotherm adsorption of the anionic Methyl Orange was found to correlate with both Langmuir and Freundlich models. The mean free energies evaluated by using the D-R model indicated a physisorption of Methyl Orange and a chemisorptions of Azure A onto keratin sponges. Finally, the functionalization of keratin sponges with Zn Al hydrotalcites nanoparticles did not affect the adsorption performances of the adsorbent toward the cationic dye Azure A, while it improved those toward the anionic Methyl Orange, increasing the related removal efficiencies from 43 to 96%. Collectively, the reported data indicates that the combination of keratin with hydrotalcites nanoparticles is a good strategy to obtain more functional adsorbent materials of potential interest for water treatment and purification.

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