Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
Int J Mol Sci ; 23(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35628195

RESUMO

The scaffold is a key element in the field of tissue engineering, especially when large defects or substitutions of pathological tissues or organs need to be clinically addressed. The expected outcome is strongly dependent on the cell-scaffold interaction and the integration with the surrounding biological tissue. Indeed, mimicking the natural extracellular matrix (ECM) of the tissue to be healed represents a further optimization that can limit a possible morphological mismatch between the scaffold and the tissue itself. For this aim, and referring to bone tissue engineering, polylactic acid (PLA) scaffolds were 3D printed with a microstructure inspired by the trabecular architecture and biologically evaluated by means of human osteosarcoma SAOS-2 cells. The cells were seeded on two types of scaffolds differing for the designed pore size (i.e., 400 and 600 µm), showing the same growth exponential trend found in the control and no significant alterations in the actin distribution. The microporous structure of the two tested samples enhanced the protein adsorption capability and mRNA expression of markers related to protein synthesis, proliferation, and osteoblast differentiation. Our findings demonstrate that 3D-printed scaffolds support the adhesion, growth, and differentiation of osteoblast-like cells and the microporous architecture, mimicking the natural bone hierarchical structure, and favoring greater bioactivity. These bioinspired scaffolds represent an interesting new tool for bone tissue engineering and regenerative medicine applications.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Osso e Ossos , Humanos , Osteogênese , Impressão Tridimensional , Alicerces Teciduais/química
2.
Nanotechnology ; 29(41): 415102, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30059014

RESUMO

Photothermal therapy (PTT) assisted by nanomaterials is a promising minimally invasive technique for cancer treatment. Here, we explore the PTT properties of a silicon- and gold-based nanostructured platform suitable for being directly integrated in fibre laser systems rather than injected into the human body, which occurs for the most commonly unreported PTT nanoagents. In particular, the photothermal properties of an array of disordered silicon nanowires coated by a thin gold film (Au/SiNWs) were tested on a monolayer of human colon adenocarcinoma cells (Caco-2) irradiated with a 785 nm laser. Au/SiNWs allowed an efficient photothermal action and simultaneous monitoring of the process evolution through the Raman signal coming from the irradiated cellular zone. Strong near infra-red (NIR) absorption, overlapping three biological windows, cell-friendly properties and effective fabrication technology make Au/SiNWs suitable both to be integrated in surgical laser tools and as an in vitro platform to develop novel PTT protocols using different cancer types and NIR sources.

3.
Int J Mol Sci ; 19(8)2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30096780

RESUMO

Cell therapy is an innovative strategy for tissue repair, since adult stem cells could have limited regenerative ability as in the case of myocardial damage. This leads to a local contractile dysfunction due to scar formation. For these reasons, refining strategy approaches for "in vitro" stem cell commitment, preparatory to the "in vivo" stem cell differentiation, is imperative. In this work, we isolated and characterized at molecular and cellular level, human Amniotic Mesenchymal Stromal Cells (hAMSCs) and exposed them to a physical Extremely Low Frequency Electromagnetic Field (ELF-EMF) stimulus and to a chemical Nitric Oxide treatment. Physically exposed cells showed a decrease of cell proliferation and no change in metabolic activity, cell vitality and apoptotic rate. An increase in the mRNA expression of cardiac and angiogenic differentiation markers, confirmed at the translational level, was also highlighted in exposed cells. Our data, for the first time, provide evidence that physical ELF-EMF stimulus (7 Hz, 2.5 µT), similarly to the chemical treatment, is able to trigger hAMSC cardiac commitment. More importantly, we also observed that only the physical stimulus is able to induce both types of commitments contemporarily (cardiac and angiogenic), suggesting its potential use to obtain a better regenerative response in cell-therapy protocols.


Assuntos
Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células-Tronco Mesenquimais/efeitos da radiação , Medicina Regenerativa , Âmnio/citologia , Âmnio/crescimento & desenvolvimento , Âmnio/efeitos da radiação , Terapia Baseada em Transplante de Células e Tecidos/métodos , Campos Eletromagnéticos , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Coração/efeitos da radiação , Humanos , Células-Tronco Mesenquimais/citologia , RNA Mensageiro/efeitos da radiação , Radiação não Ionizante
4.
Electromagn Biol Med ; 36(3): 289-294, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28704129

RESUMO

Several beneficial effects of the electromagnetic information transfer through aqueous system (EMITTAS) procedure have previously been reported in vitro. The clinical potential of this procedure has also started to be evaluated. Information flow in biological systems can be investigated through chemical and molecular approaches or by a biophysical approach focused on endogenous electrodynamic activities. Electromagnetic signals are endogenously generated at different levels of the biological organization and, likely, play an active role in synchronizing internal cell function or local/systemic adaptive response. Consequently, each adaptive response can be described by its specific electromagnetic pattern and, therefore, correlates with a unique and specific electromagnetic signature. A biophysical procedure synchronously integrating the EMITTAS procedure has already been applied for the treatment of articular pain, low-back pain, neck pain and mobility, fluctuating asymmetry, early-stage chronic kidney disease, refractory gynecological infections, minor anxiety and depression disorders. This clinical strategy involves a single treatment, since the EMITTAS procedure allows the patient to continue his/her own personal treatment at home by means of self-administration of the recorded aqueous system. A significant and long-lasting improvement has been reported, showing a potential beneficial use of this biophysical procedure in the management of common illnesses in an efficient, effective and personalized way. Data from recent studies suggest that aqueous systems may play a key role in providing the basis for recording, storing, transferring and retrieving clinically effective quanta of biological information. These features likely enable to trigger local and systemic self-regulation and self-regeneration potential of the organism.


Assuntos
Fenômenos Eletromagnéticos , Magnetoterapia , Água , Humanos
5.
Electromagn Biol Med ; 34(2): 147-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26098527

RESUMO

Several years ago just before Christmas, in a small meeting room at the Institute of Pharmacology at the University of Rome, we had the opportunity to attend a meeting on "The role of QED in medicine" by Emilio Del Giudice and Giuliano Preparata. Before that meeting, we were more oriented towards a mechanistic view of Biochemistry and Medicine, believing that chemical reactions could only take place when a random collision between molecules with a gain in energy takes place. We envisioned water as just a solvent in which was possible to dissolve a solute. After we listened to Giuliano's and Emilio's speech on the "New physics of water", and on "The possible origin of coherence in cell, tissues and the interaction of very weak and low frequency magnetic fields with the ions, systems of the cell", we realized that living organisms are complex electrochemical systems which evolved in a relatively narrow range of well-defined environmental parameters. Environmental natural electro-magnetic fields are an ubiquitous factor in nature. If nature gave certain organisms the ability to receive information about the environment via invisible electromagnetic signals, then there must also the capability to discriminate between significant and meaningless ones. Bearing in mind that electromagnetic fields can be perceived by living organisms by means a resonance effect, we should not be amazed if they can be able to induce different biological effects. The work that we will present in memory of Emilio is based on the hypotheses that an aqueous system a chemical differentiation agent such as retinoic acid (RA) were electronically captured and transferred to the culture medium of Neuroblastoma Cell Line (LAN-5) and the proliferation rate was assessed to assess cell responses to the electromagnetic information transfer through the aqueous system. Like those enfolded in living organisms could play a synergic role in modulating biological functions, generating dissipative structures under appropriate patterns of electromagnetic signals providing basis for storing and retrieving biological activities. An external electro-magnetic stimulus from a source molecule can be stored, translated, and transferred by the aqueous systems to the biological target, selectively driving their endogenous activity and mimicking the effect of a source molecule.


Assuntos
Fenômenos Eletromagnéticos , Teoria Quântica , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Tretinoína/farmacologia
6.
Electromagn Biol Med ; 32(4): 484-99, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23323834

RESUMO

Only recently has the critical importance of electromagnetic (EM) field interactions in biology and medicine been recognized. We review the phenomenon of resonance signaling, discussing how specific frequencies modulate cellular function to restore or maintain health. The application of EM-tuned signals represents more than merely a new tool in information medicine. It can also be viewed in the larger context of EM medicine, the all-encompassing view that elevates the EM over the biochemical. The discovery by Zhadin that ultrasmall magnetic intensities are biologically significant suggests that EM signaling is endogenous to cell regulation, and consequently that the remarkable effectiveness of EM resonance treatments reflects a fundamental aspect of biological systems. The concept that organisms contain mechanisms for generating biologically useful electric signals is not new, dating back to the nineteenth century discovery of currents of injury by Matteucci. The corresponding modern-day version is that ion cyclotron resonance magnetic field combinations help regulate biological information. The next advance in medicine will be to discern and apply those EM signaling parameters acting to promote wellness, with decreasing reliance on marginal biochemical remediation and pharmaceuticals.


Assuntos
Campos Eletromagnéticos , Medicina/métodos , Transdução de Sinais/efeitos da radiação , Animais , Diagnóstico , Humanos , Magnetoterapia
7.
Sci Rep ; 13(1): 11370, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452161

RESUMO

An early and accurate detection of different subtypes of tumors is crucial for an effective guidance to personalized therapy and in predicting the ability of tumor to metastasize. Here we exploit the Surface Enhanced Raman Scattering (SERS) platform, based on disordered silver coated silicon nanowires (Ag/SiNWs), to efficiently discriminate genomic DNA of different subtypes of melanoma and colon tumors. The diagnostic information is obtained by performing label free Raman maps of the dried drops of DNA solutions onto the Ag/NWs mat and leveraging the classification ability of learning models to reveal the specific and distinct physico-chemical interaction of tumor DNA molecules with the Ag/NW, here supposed to be partly caused by a different DNA methylation degree.


Assuntos
Nanofios , Neoplasias , Humanos , Análise Espectral Raman , DNA , Nanofios/química , Neoplasias/diagnóstico , Neoplasias/genética , Genômica
8.
Bioengineering (Basel) ; 10(5)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37237637

RESUMO

Material extrusion (MEX), commonly referred to as fused deposition modeling (FDM) or fused filament fabrication (FFF), is a versatile and cost-effective technique to fabricate suitable scaffolds for tissue engineering. Driven by a computer-aided design input, specific patterns can be easily collected in an extremely reproducible and repeatable process. Referring to possible skeletal affections, 3D-printed scaffolds can support tissue regeneration of large bone defects with complex geometries, an open major clinical challenge. In this study, polylactic acid scaffolds were printed resembling trabecular bone microarchitecture in order to deal with morphologically biomimetic features to potentially enhance the biological outcome. Three models with different pore sizes (i.e., 500, 600, and 700 µm) were prepared and evaluated by means of micro-computed tomography. The biological assessment was carried out seeding SAOS-2 cells, a bone-like cell model, on the scaffolds, which showed excellent biocompatibility, bioactivity, and osteoinductivity. The model with larger pores, characterized by improved osteoconductive properties and protein adsorption rate, was further investigated as a potential platform for bone-tissue engineering, evaluating the paracrine activity of human mesenchymal stem cells. The reported findings demonstrate that the designed microarchitecture, better mimicking the natural bone extracellular matrix, favors a greater bioactivity and can be thus regarded as an interesting option for bone-tissue engineering.

9.
Adv Sci (Weinh) ; 10(24): e2301925, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37357140

RESUMO

Today, the key methodology to study in vitro or in vivo electrical activity in a population of electrogenic cells, under physiological or pathological conditions, is by using microelectrode array (MEA). While significant efforts have been devoted to develop nanostructured MEAs for improving the electrophysiological investigation in neurons and cardiomyocytes, data on the recording of the electrical activity from neuroendocrine cells with MEA technology are scarce owing to their weaker electrical signals. Disordered silicon nanowires (SiNWs) for developing a MEA that, combined with a customized acquisition board, successfully capture the electrical signals generated by the corticotrope AtT-20 cells as a function of the extracellular calcium (Ca2+ ) concentration are reported. The recorded signals show a shape that clearly resembles the action potential waveform by suggesting a natural membrane penetration of the SiNWs. Additionally, the generation of synchronous signals observed under high Ca2+ content indicates the occurrence of a collective behavior in the AtT-20 cell population. This study extends the usefulness of MEA technology to the investigation of the electrical communication in cells of the pituitary gland, crucial in controlling several essential human functions, and provides new perspectives in recording with MEA the electrical activity of excitable cells.


Assuntos
Nanofios , Células Neuroendócrinas , Humanos , Silício , Microeletrodos , Miócitos Cardíacos
10.
Biomedicines ; 12(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38275391

RESUMO

BACKGROUND: The regeneration of severe traumatic muscle injuries is an unsolved medical need that is relevant for civilian and military medicine. In this work, we produced a critically sized nonhealing muscle defect in a mouse model to investigate muscle degeneration/healing phases. MATERIALS AND METHODS: We caused a freeze injury (FI) in the biceps femoris of C57BL/6N mice. From day 1 to day 25 post-injury, we conducted histological/morphometric examinations, an analysis of the expression of genes involved in inflammation/regeneration, and an in vivo functional evaluation. RESULTS: We found that FI activates cytosolic DNA sensing and inflammatory responses. Persistent macrophage infiltration, the prolonged expression of eMHC, the presence of centrally nucleated myofibers, and the presence of PAX7+ satellite cells at late time points and with chronic physical impairment indicated inadequate repair. By looking at stem-cell-based therapeutic protocols of muscle repair, we investigated the crosstalk between M1-biased macrophages and human amniotic mesenchymal stem cells (hAMSCs) in vitro. We demonstrated their reciprocal paracrine effects where hAMSCs induced a shift of M1 macrophages into an anti-inflammatory phenotype, and M1 macrophages promoted an increase in the expression of hAMSC immunomodulatory factors. CONCLUSIONS: Our findings support the rationale for the future use of our injury model to exploit the full potential of in vivo hAMSC transplantation following severe traumatic injuries.

11.
Nanomedicine ; 8(3): 299-307, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21723243

RESUMO

Aiming to explore the mechanisms modulating cell-carbon nanotube interactions, we investigated whether Ca(2+) ion balancing between intra- and extracellular environments could be affected by multiwalled carbon nanotubes (MWCNTs). We analyzed the effects induced by two different kinds of MWCNTs (as prepared and annealed at 2400°C) on the intracellular Ca(2+) ion levels in rat electrically sensitive cells and on the intercellular junction integrity of rat adenocarcinoma colon cells and platelet aggregation ability, which depend on the Ca(2+) concentration in the medium. MWCNTs, purified by annealing and more electroconductive as compared to nonannealed MWCNTs, affected Ca(2+) ion balancing between extra- and intracellular environments and induced changes on Ca(2+) ion-dependent cellular junctions and platelet aggregation, behaving as the calcium chelator ethylene glycol tetraacetic acid. This could be due to the sorption of cationic Ca(2+) ions on CNTs surface because of the excess of negatively charged electrons on the aromatic units formed on MWCNTs after annealing. From the ClinicAL Editor: The authors investigated whether Ca(2+) ion balance between intra- and extracellular space can be modulated by multiwalled carbon nanotubes (MWCNTs). Annealed nanotubes induced changes on Ca(2+) dependent cellular junctions and platelet aggregation, behaving similary to ethylene glycol tetraacetic acid, an established calcium chelator.


Assuntos
Cálcio/metabolismo , Condutividade Elétrica , Nanotecnologia/métodos , Nanotubos de Carbono/química , Animais , Linhagem Celular Tumoral , Forma Celular , Impedância Elétrica , Técnicas Eletroquímicas , Elétrons , Humanos , Junções Intercelulares/metabolismo , Espaço Intracelular/metabolismo , Íons , Agregação Plaquetária , Plasma Rico em Plaquetas/metabolismo , Ratos , Compostos de Estanho/química
12.
J Ultrasound Med ; 31(7): 1123-36, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22733861

RESUMO

Automated computer-aided detection systems for measurement of the carotid intima-media thickness (IMT) are becoming popular. These systems yield lumen-intima (LI) and media-adventitia (MA) borders. In this work, we developed and validated a novel and patented completely automated IMT measurement system called carotid measurement using dual snakes (CMUDS): a class of AtheroEdge system (Global Biomedical Technologies, Inc, Roseville, CA). CMUDS is modeled as a dual parametric system corresponding to LI and MA borders with initialization from the far adventitia layer. The novelty of CMUDS is the first-order absolute moment-based external energy, which provides stable deformation. The dual snakes evolve simultaneously and are forced to maintain a regularized distance to prevent collapsing or bleeding. Two independent readers manually traced the LI/MA boundaries of a multi-institutional, multi-ethnic, and multi-scanner database of 665 longitudinal images for performance evaluation. CMUDS was also benchmarked against a previously developed automated technique. CMUDS correctly processed 660 images (99.2% success). The differences between the CMUDS and two manual IMT measurements (mean ± SD) were 0.013 ± 0.216 and -0.021 ± 0.197 mm, respectively. The corresponding figures of merit for CMUDS compared to reader tracings were 98.4% and 97.5%. Compared to the previous technique (IMT differences, 0.022 ± 0.276 and -0.012 ± 0.266 mm), CMUDS improved accuracy (Wilcoxon P < 0.009) and variability (Fisher P < 10(-8)). Among different resolution images from original equipment manufacturer ultrasound scanners, CMUDS performed best with high-resolution images corresponding to 0.0789 mm/pixel. Accuracy in IMT measurement with the proposed automated CMUDS technique makes this system adaptable to large multi-center studies, in which such an IMT measurement system would be very useful tool.


Assuntos
Algoritmos , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Micromachines (Basel) ; 13(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36144012

RESUMO

We exploit Surface-Enhanced Raman Scattering (SERS) to investigate aqueous droplets of genomic DNA deposited onto silver-coated silicon nanowires, and we show that it is possible to efficiently discriminate between spectra of tumoral and healthy cells. To assess the robustness of the proposed technique, we develop two different statistical approaches, one based on the Principal Components Analysis of spectral data and one based on the computation of the ℓ2 distance between spectra. Both methods prove to be highly efficient, and we test their accuracy via the Cohen's κ statistics. We show that the synergistic combination of the SERS spectroscopy and the statistical analysis methods leads to efficient and fast cancer diagnostic applications allowing rapid and unexpansive discrimination between healthy and tumoral genomic DNA alternative to the more complex and expensive DNA sequencing.

14.
Micromachines (Basel) ; 12(3)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806524

RESUMO

This article demonstrates the possibility to use a novel powerful approach based on Raman mapping of analyte solutions drop casted on a disordered array of Ag covered silicon nanowires (Ag/SiNWs), to identify the characteristic spectral signal of the four DNA bases, adenine (A), thymine (T), cytosine (C), and guanine (G), at concentration as low as 10 ng/µL, and to study their specific way of interacting with the nanostructured substrate. The results show a distinctive and amplified interaction of guanine, the base that is most susceptible to oxidation, with the nanostructured surface. Our findings explain the recently revealed diverse behaviour of cancer and normal DNA deposited on the same Ag/SiNWs, which is ascribed to mechanical deformation and base lesions present on the oxidised DNA molecule backbone and causes detectable variation in the Raman signal, usable for diagnostic purposes. The notable bio-analytical capability of the presented platform, and its sensitivity to the molecule mechanical conformation at the single-base level, thus provides a new reliable, rapid, label-free DNA diagnostic methodology alternative to more sophisticated and expensive sequencing ones.

15.
Mater Sci Eng C Mater Biol Appl ; 122: 111951, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641882

RESUMO

Genomic deoxyribonucleic acid (DNA) stores and carries the information required to maintain and replicate cellular life. While much efforts have been devoted in decoding the sequence of DNA basis to detect the genetic mutations related to cancer disease, it is becoming clear that physical properties, like structural conformation, stiffness and shape, can play an important role to recognize DNA modifications. Here, silver-coated silicon nanowires (Ag/SiNWs) are exploited as Raman spectroscopic platform to easily discriminate healthy and cancer genomic DNA, extracted from human normal skin and malignant melanoma cells, respectively. In particular, aqueous DNA droplets are directly deposited onto a forest of Ag/SiNWs and Raman maps are acquired after sample dehydration. By applying principal component analysis (PCA) to the Raman spectra collected within the droplets, healthy and cancer cell DNA can be distinguished without false negative identifications and with few false positive results (< 2%). The discrimination occurs regardless the analysis of specific DNA sequencing, but through Raman bands strictly related to the interfacing of the DNA and the NWs. The observed phenomenon can be ascribed to conformational differences and/or diverse charge properties between healthy and cancer cell DNA determining a different arrangement of the molecules adsorbed onto the NWs upon water evaporation. The unique interaction with DNA and facile fabrication technology make Ag/SiNWs an effective platform for a robust, rapid and label-free cancer diagnosis, as well as a potential tool to investigate physical properties of DNA.


Assuntos
Nanofios , Prata , DNA , Células Epiteliais , Genômica , Humanos , Silício , Análise Espectral Raman
16.
Electromagn Biol Med ; 29(3): 63-71, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20707641

RESUMO

The aim of this work is the study of the effect of electromagnetic radiations (ELF-EMF) tuned to the calcium cyclotron resonance condition of 7.0 Hz, 9.2 microT on the differentiation process of pituitary corticotrope-derived AtT20 D16V cells. These cells respond to nerve growth factor by extending neurite-like processes. To establish whether exposure to the field could influence the molecular biology of the pituitary gland, a corticotrope-derived cells line (AtT20 D16V) was exposed to ELF-EMF at a frequency of 7.0 Hz, 9.2 microT electromagnetic field by a Vega Select 719 power supply. Significant evidence was obtained to conclude that as little as 36 h exposure to the Ca(2+) ICR condition results in enhanced neurite outgrowth, with early expression and aggregation of the neuronal differentiation protein NF-200 into neurite structures.


Assuntos
Cálcio , Diferenciação Celular/efeitos da radiação , Corticotrofos/citologia , Corticotrofos/efeitos da radiação , Ciclotrons , Campos Eletromagnéticos , Linhagem Celular , Proliferação de Células/efeitos da radiação , Corticotrofos/metabolismo , Neuritos/metabolismo , Neuritos/efeitos da radiação , Proteínas de Neurofilamentos/genética , Reação em Cadeia da Polimerase , Fatores de Tempo
17.
Nanoscale ; 12(3): 1759-1778, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31895375

RESUMO

Ultrasmall superparamagnetic iron oxide nanoparticles with a size <5 nm are emerging nanomaterials for their excellent biocompatibility, chemical stability, and tunable surface modifications. The applications explored include dual-modal or multi-modal imaging, drug delivery, theranostics and, more recently, magnetic resonance angiography. Good biocompatibility and biosafety are regarded as the preliminary requirements for their biomedical applications and further exploration in this field is still required. We previously synthesized and characterized ultrafine (average core size of 3 nm) silica-coated superparamagnetic iron oxide fluorescent nanoparticles, named sub-5 SIO-Fl, uniform in size, shape, chemical properties and composition. The cellular uptake and in vitro biocompatibility of the as-synthesized nanoparticles were demonstrated in a human colon cancer cellular model. Here, we investigated the biocompatibility of sub-5 SIO-Fl nanoparticles in human Amniotic Mesenchymal Stromal/Stem Cells (hAMSCs). Kinetic analysis of cellular uptake showed a quick nanoparticle internalization in the first hour, increasing over time and after long exposure (48 h), the uptake rate gradually slowed down. We demonstrated that after internalization, sub-5 SIO-Fl nanoparticles neither affect hAMSC growth, viability, morphology, cytoskeletal organization, cell cycle progression, immunophenotype, and the expression of pro-angiogenic and immunoregulatory paracrine factors nor the osteogenic and myogenic differentiation markers. Furthermore, sub-5 SIO-Fl nanoparticles were intravenously injected into mice to investigate the in vivo biodistribution and toxicity profile for a time period of 7 weeks. Our findings showed an immediate transient accumulation of nanoparticles in the kidney, followed by the liver and lungs, where iron contents increased over a 7-week period. Histopathology, hematology, serum pro-inflammatory response, body weight and mortality studies demonstrated a short- and long-term biocompatibility and biosafety profile with no apparent acute and chronic toxicity caused by these nanoparticles in mice. Overall, these results suggest the feasibility of using sub-5 SIO-Fl nanoparticles as a promising agent for stem cell magnetic targeting as well as for diagnostic and therapeutic applications in oncology.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Nanopartículas de Magnetita/química , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Dióxido de Silício , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Feminino , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Desenvolvimento Muscular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Dióxido de Silício/química , Dióxido de Silício/farmacologia
18.
Electromagn Biol Med ; 28(1): 71-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19337897

RESUMO

According to Quantum Electro-Dynamical Theory by G. Preparata, liquid water can be viewed as an equilibrium between of two components: coherent and incoherent ones. The coherent component is contained within spherical so called "coherence domains" (CDs) where all molecules synchronously oscillate with the same phase. CDs are surrounded by the incoherent component where molecules oscillate with casual phases regarding each other. The existence of coherent domain in water has been demonstrated in a set of experiments on pure water exposed to high voltage, under this condition the electric field concentrates inside the water, arranging the water molecules to form high ordered structure. Recently has been studied the influence of combined static and alternating parallel magnetic fields on the current through the aqueous solution of glutamic acid; outlining the relevance of low frequency electro-magnetic field in interacting with biological target. Additional results demonstrate that at combined static and alternating parallel, magnetic fields matching the ion cyclotron energy resonance of a particular charged molecule into biological tissue an intrinsic weak magnetic field is generated by ion currents in the cell. These results should increase the reliability and the clinical feasibility of the use of electromagnetic field, tuned at ion cyclotron resonance of charged molecules, as a biophysical approach to interfere with biological mechanisms. We demonstrate that Exposure of human epithelial cell to ion cyclotron energy resonance generated by a commercial electromedical device (Vega select 719) tuned to calcium ion at 7 Hz act as a differentiation factor, thus opening up the possibility to use particular extremely low frequency electro magnetic field protocols, in informative medicine.


Assuntos
Campos Eletromagnéticos , Animais , Biofísica/métodos , Remodelação Óssea , Ciclotrons , Eletroquímica/métodos , Desenho de Equipamento , Humanos , Íons , Informática Médica/métodos , Modelos Biológicos , Água/química
19.
J Tissue Eng Regen Med ; 13(6): 1031-1043, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30942524

RESUMO

Cell therapy represents a promising alternative strategy for end-stage liver disease, and hepatic progenitors are the best candidates. The possibility to maximize the paracrine effects of transplanted cells represents a great potential benefit for cell therapy success. We studied how cell type and microenvironment modulate the Wnt/ß-catenin signaling in vitro and in vivo. In vitro, the onset of hepatocyte commitment was characterized by the presence of nuclear truncated ß-catenin. In vivo, we analyzed the effect of human hepatic progenitors on damage recovery and functional regeneration in a mouse model of acute liver injury, either in combination or in absence of a selected mix of hepatogenic factors. Animals injected with human hepatic progenitors and hepatogenic factors showed improved engraftment triggering the Wnt/ß-catenin signaling cascade. Human hepatic progenitors expressing the human oval cell marker OV6 displayed a consistent colocalization with ß-catenin and colocalized with Wnt1 main ligand of the canonical pathway. Wnt5a, on the contrary, was expressed in distinct liver cell populations. Epithelial mesenchymal transition-related markers showed enhanced expression and wider distribution, and the hepato-mesenchymal population Thy1 + CK19- was also present. Control animals injected with hepatogenic factors alone exhibited higher ß-catenin, decreased Wnt5a levels, and persistent proliferation of the hepato-mesenchymal population. In conclusion, the combination of human hepatic progenitors with selected hepatogenic factors creates a positive synergy with local microenvironment, ameliorates cell engraftment, stimulates and accelerates regenerative process, and improves the rescue of hepatic function by modulating the Wnt/ßcatenin signaling and activating hepato-mesenchymal population.


Assuntos
Sangue Fetal/citologia , Fígado/lesões , Transplante de Células-Tronco , Células-Tronco/citologia , Via de Sinalização Wnt , Animais , Diferenciação Celular , Proliferação de Células , Humanos , Fígado/patologia , Masculino , Camundongos SCID
20.
Electromagn Biol Med ; 27(3): 230-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18821199

RESUMO

The specific aim of the present work concerns the effectiveness of low-frequency electromagnetic fields treatment to modify biochemical properties of human keratinocytes (HaCaT). Cells exposed to a 7 Hz electromagnetic field, tuned to calcium ion cyclotron resonance (ICR), showed modifications in the cytoskeleton. These modifications were related to different actin distributions as revealed by phalloidin fluorescence analysis. Indirect immunofluorescence with fluorescent antibodies against involucrin and beta catenin, both differentiation and adhesion markers, revealed an increase in involucrin and beta-catenin expression, indicating that exposure to electromagnetic field carries keratinocytes to an upper differentiation level. This study confirms our previous observation and supports the hypothesis that a 7 Hz calcium ICR electromagnetic field may modify cell biochemistry and interfere in the differentiation and cellular adhesion of normal keratinocytes, suggesting the possibility to use ICR electromagnetic therapy for the treatment of undifferentiated diseases.


Assuntos
Cálcio/metabolismo , Diferenciação Celular/efeitos da radiação , Ciclotrons , Queratinócitos/citologia , Queratinócitos/efeitos da radiação , Actinas/metabolismo , Western Blotting , Terapia por Estimulação Elétrica , Campos Eletromagnéticos , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Queratinócitos/metabolismo , Precursores de Proteínas/metabolismo , Reprodutibilidade dos Testes , beta Catenina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA