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1.
Int J Biometeorol ; 65(1): 31-44, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33236243

RESUMEN

Atmospheric electric fields (AEFs) are produced by both natural processes and electrical infrastructure and are increasingly recognized to influence and interfere with various organisms and biological processes, including human well-being. Atmospheric electric fields, in particular electromagnetic fields (EMFs), currently attract a lot of scientific attention due to emerging technologies such as 5G and satellite internet. However, a broader retrospective analysis of available data for both natural and artificial AEFs and EMFs is hampered due to a lack of a semantic approach, preventing data sharing and advancing our understanding of its intrinsic links. Therefore, here we create an ontology (ENET_Ont) for existing (big) data on AEFs within the context of biological systems that is derived from different disciplines that are distributed over many databases. Establishing an environment for data sharing provided by the proposed ontology approach will increase the value of existing data and facilitate reusability for other communities, especially those focusing on public health, ecology, environmental health, biology, climatology as well as bioinformatics.


Asunto(s)
Electricidad , Campos Electromagnéticos , Humanos , Difusión de la Información , Estudios Retrospectivos , Semántica
2.
Nanotechnology ; 30(5): 055502, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30517085

RESUMEN

Ternary nanocomposites made of γ-iron oxide and aluminum-doped zinc oxide (γ-Fe2O3/Al-ZnO NCs), with different metal oxides ratio (0%-100%) were prepared through a solvothermal sol-gel process. The synthesized materials were characterized by x-ray diffraction, UV-vis spectroscopy, photoluminescence (PL), scanning electron microscope and BET analysis. Characterization results demonstrated that the ternary γ-Fe2O3/Al-ZnO NCs are mainly constituted by γ-Fe2O3 and Al-ZnO individual phases, while structural and physical properties like surface area, pore size, optical band gap, PL and electrical conductivity were deeply affected by the composition of nanocomposite. The synthesized γ-Fe2O3/Al-ZnO NCs were employed to prepare conductometric gas sensors, then their sensing performances toward acetone were also investigated. Results revealed enhanced sensing performance of nanocomposites than both pure γ-Fe2O3 and Al-ZnO phases. In particular, the γ-Fe2O3(33%)/Al-ZnO based gas sensor showed the best sensing properties, like a high response of R air/R gas = 29, a short response time of 3 s, in addition to an improved selectivity toward acetone versus ethanol at an operating temperature of 200 °C. Overall, ternary γ-Fe2O3/Al-ZnO NCs appear to be promising for the development of conductometric acetone sensors.

3.
J Anim Physiol Anim Nutr (Berl) ; 101(5): 914-924, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27184526

RESUMEN

Twelve lactating sows were used to evaluate the effects of reducing dietary crude protein (CP) (14% vs. 12%) and increasing neutral detergent fibre (NDF) levels (18% vs. 22%) on litter performance, total tract apparent digestibility and manure composition in a 4 × 4 latin square arrangement during a 36-day lactation period. Diets were isoenergetic (2.9 Mcal ME/kg) and had similar total lysine content (0.9%). In addition, a second aim was to compare a reference external marker method (Cr2 O3 ) with an internal feed marker [acid-insoluble ash (AIA)] for the calculation of apparent total tract digestibility of nutrients in lactating sows. The reduction of dietary CP level in lactating sows had no effect on either live-weight or backfat thickness or apparent total tract digestibility of nutrients. However, the piglets' average daily gain (ADG) was reduced in low dietary CP diets, which suggests that sows reduced milk production due to an underestimation of certain essential amino acid requirements (e.g. valine). The increase of dietary NDF level did not affect sow and litter performance. Nevertheless, the total tract apparent digestibility of organic matter, CP and carbohydrates was reduced, and ether extract digestion was increased in high NDF compared to normal NDF diets equally balanced for ME and lysine content. The coefficients of total tract apparent digestibility of nutrients in lactating sows were greater when using AIA compared to Cr2 O3 marker, regardless of dietary CP or NDF level, but their coefficients of variation were lower in the former than in the latter. In lactating sows, a trade-off between litter performance and nutrient digestion is established when reducing dietary CP or increasing NDF levels while maintaining similar lysine content through synthetic amino acids and balancing metabolizable energy through dietary fat sources.


Asunto(s)
Animales Recién Nacidos/fisiología , Proteínas en la Dieta/administración & dosificación , Digestión/fisiología , Porcinos/fisiología , Alimentación Animal/análisis , Crianza de Animales Domésticos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Fibras de la Dieta , Femenino , Aumento de Peso
4.
Phys Chem Chem Phys ; 18(31): 21331-9, 2016 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-27427175

RESUMEN

Nanoparticle-based cancer diagnosis-therapy integrative systems (cancer theranostics) represent an emerging approach in oncology. To address this issue in the present work iron oxide (γ-Fe2O3-maghemite) nanoparticles (IONPs) were encapsulated within the matrix of (bis(p-sulfonatophenyl)phenylphosphine)-methoxypolyethylene glycol-thiol (mPEG) polymer vesicles using a two-step process for active chemotherapeutic cargo loading in cancer theranostics. This formation method gives simple access to highly reactive surface groups present on IONPs together with good control over the vesicle size (50-100 nm). The simultaneous loading of a chemotherapeutic drug cargo (doxorubicin) and its in vitro release in cancer cells was achieved. The feasibility of controlled drug release under different pH conditions was demonstrated in the case of encapsulated doxorubicin molecules, showing the viability of the concept of stimulated drug delivery for magneto-chemotherapy. These polymer-magnetic nanocargoes (PMNCs) exhibit enhanced contrast properties that open potential applications for magnetic resonance imaging. These self-assembled magnetic polymersomes can be used as efficient multifunctional nanocarriers for combined therapy and imaging.


Asunto(s)
Sistemas de Liberación de Medicamentos , Hipertermia Inducida , Nanopartículas de Magnetita , Neoplasias/diagnóstico , Neoplasias/terapia , Animales , Portadores de Fármacos , Compuestos Férricos , Humanos , Imagen por Resonancia Magnética
5.
Biochim Biophys Acta ; 1840(7): 2139-51, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24589913

RESUMEN

BACKGROUND: Applications of cell electropermeabilization are rapidly growing but basic concepts are still unclear. In particular, the impact of electric pulse repetition rate in the efficiency of permeabilization has not yet been understood. METHODS: The impact of electric pulse repetition rate in the efficiency of permeabilization was analyzed in experiments performed on potato tissue and partially transposed on mice liver. On potato tissue, pulses with durations of 100µs or 10ns are applied. The intensity of permeabilization was quantified by means of bioimpedance changes and electric current measurements and a new index was defined. RESULTS: For the two pulse durations tested, very low repetition rates (below 0.1Hz) are much more efficient to achieve cell permeabilization in potato tissue. In mice liver, using 100µs pulses, the influence of the repetition rate is more complex. Indeed, repetition rates of 1Hz and 10Hz are more efficient than 100Hz or 1kHz, but not the repetition rate of 0.1Hz for which there is an impact of the living mice organism response. CONCLUSIONS: We propose that the effects reported here might be caused by an electroporation-induced cell membrane 'electro-desensitization' which requires seconds to dissipate due to membrane resealing. GENERAL SIGNIFICANCE: This study not only reinforces previous observations, but moreover it sustains a new concept of 'electro-desensitization' which is the first unifying mechanism enabling to explain all the results obtained until now both in vitro and in vivo, with long and short pulses.


Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Impedancia Eléctrica , Solanum tuberosum/fisiología , Animales , Electroporación/métodos , Hígado/fisiología , Ratones , Pulso Arterial , Solanum tuberosum/citología
6.
Water Sci Technol ; 72(6): 974-82, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26360758

RESUMEN

Four partial carbonized nanoporous resins (PCNRs), based on organic xerogel compounds, were synthesised by the sol-gel method from pyrogallol and formaldehyde mixtures in water using picric acid as catalyst. The PCNRs were prepared at different pyrolysis temperatures: T(1) = 200 °C (PF-200), T(2) = 300 °C (PF-300), T(3) = 400 °C (PF-400), or T(4) = 500 °C (PF-500). The PCNRs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transformed infrared spectroscopy, and nitrogen porosimetry. The obtained results show that PF-200 is more efficient for the removal of Pb(2+) from aqueous solution than the other adsorbent prepared in this study. The characteristics of lead uptake by PF-200 were explored using well-established and effective parameters including pH, contact time, initial metal ion concentration and temperature. Optimum adsorption of Pb(2+), using PF-200, was observed at pH 4.5. The Langmuir model gave a better fit than the other models, and kinetic studies revealed that the adsorption was well fitted by the pseudo second-order kinetic model and thermodynamic properties, i.e., Gibbs free energy change, enthalpy change and entropy change, showed that adsorption of Pb(2+) onto PF-200 was endothermic, spontaneous and feasible in the temperature range of 298-328 K.


Asunto(s)
Nanoestructuras/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Cinética , Microscopía Electrónica de Rastreo , Temperatura , Termodinámica , Agua , Difracción de Rayos X
7.
Int J Obes (Lond) ; 38(5): 707-13, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23979219

RESUMEN

BACKGROUND: It has been suggested that the metabolic benefits of physical exercise could be mediated by myokines. We examined here the effect of exercise training on skeletal muscle expression of a panel of myokines in humans. Pathways regulating myokine expression were investigated in human myotubes. METHODS: Eleven obese non-diabetic male subjects were enrolled in an 8-week endurance training program. Insulin sensitivity was assessed by an oral glucose tolerance test. Subcutaneous adipose tissue and Vastus lateralis muscle biopsy samples were collected before and after training. RNAs were prepared from adipose tissue and skeletal muscle. Primary culture of myoblasts was established. RESULTS: As expected, exercise training improved aerobic capacity and decreased fat mass. No significant change in interleukin 6, fibroblast growth factor 21, myostatin (MSTN) or irisin mRNA level was found in muscle after training. A twofold increase in apelin mRNA level was found in muscle but not in adipose tissue. No change in circulating myokine and adipokine plasma levels was observed in the resting state in response to training. Interestingly, apelin was significantly expressed and secreted in primary human myotubes. Apelin gene expression was upregulated by cyclic AMP and calcium, unlike the other myokines investigated. Importantly, changes in muscle apelin mRNA levels were positively related to whole-body insulin sensitivity improvement. CONCLUSION: Collectively, our data show that exercise training upregulates muscle apelin expression in obese subjects. Apelin expression is induced by exercise signaling pathways and secreted in vitro in human primary myotubes, and may behave as a novel exercise-regulated myokine with autocrine/paracrine action.


Asunto(s)
Ejercicio Físico , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Resistencia Física , Adulto , Apelina , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/metabolismo , Fibronectinas/metabolismo , Humanos , Resistencia a la Insulina , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Interleucina-6/metabolismo , Masculino , Miostatina/metabolismo , Obesidad/prevención & control , Grasa Subcutánea/metabolismo , Regulación hacia Arriba
8.
J Theor Biol ; 360: 83-94, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25010659

RESUMEN

The aim of this paper is to present a new model of in vitro cell electropermeabilization, which describes separately the conducting state and the permeable state of the membrane submitted to high voltage pulses. We first derive the model based on the experimental observations and we present the numerical methods to solve the non-linear partial differential equations. We then present numerical simulations that corroborate qualitatively the experimental data dealing with the uptake of propidium iodide (PI) after millipulses. This tends to justify the validity of our modeling. Forthcoming work will be to calibrate the parameters of the model for quantitative description of the uptake.


Asunto(s)
Membrana Celular/metabolismo , Conductividad Eléctrica , Modelos Biológicos , Simulación por Computador , Técnicas In Vitro , Permeabilidad , Propidio/farmacocinética
9.
RSC Adv ; 14(38): 27622-27633, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39221124

RESUMEN

Cobalt-doped zinc oxide nanoparticles (NPs) were synthesized using a modified sol-gel method. Thereafter, the obtained powder was deposited on a Suprasil glass substrate by employing a pulsed laser deposition (PLD) technique. X-ray diffraction analysis with Rietveld refinement confirmed a hexagonal wurtzite ZnO phase belonging to the P63 mc space group for both samples in the NP and thin film forms. In particular, the thin film exhibited an intensive (002) XRD peak, indicating that it had a preferred c-axis orientation owing to the self-texturing mechanism. No segregated secondary phases were detected. The crystallite structure, morphology, and size were investigated using high-resolution transmission electron microscopy (HRTEM). To study the crystalline quality, structural disorder, and defects in the host lattice, we employed Raman spectroscopy. UV-vis-NIR spectroscopy was performed to confirm the nature of the Co-doped ZnO NP powder and the film. The chemical states of oxygen and zinc in the thin film sample were also investigated via X-ray photoelectron spectroscopy (XPS). The M-T curve could be successfully fitted using both the three-dimensional (3D) spin-wave model and Curie-Weiss law, confirming the mixed state existence of weak ferromagnetic (FM) and paramagnetic (PM) phases. Magnetic interaction was quantitatively studied and explained by polaronic percolation of bound magnetic polarons (BMPs). Analysis of magnetic symmetry of the topological antiferromagnetic as-deposited thin film using torque measurements was performed. Based on a phenomenological model, it was revealed that the structure gives rise to uniaxial magneto-crystalline anisotropy (UMA) with the magnetic easy axis parallel to the c-axis.

10.
Neurocrit Care ; 19(2): 192-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23896815

RESUMEN

BACKGROUND: As important mediators of solute transport at the blood-brain and blood-cerebrospinal fluid barriers, ATP-binding cassette (ABC) transporters (including ABCB1, ABCC1, and ABCC2), impact the bioavailability of drugs and endogenous substrates in the brain. While several ABCB1, ABCC1, and ABCC2 single nucleotide polymorphisms (SNPs) have been identified, their impact on outcome after traumatic brain injury (TBI) is unknown. HYPOTHESIS: ABCB1, ABCC1, and ABCC2 SNPs are associated with Glasgow Outcome Scale (GOS) score after TBI. METHODS: DNA samples from 305 adult patients with severe TBI (Glasgow Coma Scale, GCS score ≤ 8) were genotyped for tagging SNPs of ABCB1 (rs1045642; rs1128503), ABCC1 (rs212093; rs35621; rs4148382), and ABCC2 (rs2273697). For each SNP, patients were dichotomized based on presence of variant allele for multivariate analysis to determine associations with GOS assigned at 6 months adjusting for GCS, Injury Severity score, age, and patient sex. RESULTS: For ABCB1 rs1045642, patients homozygous for the T allele were less likely to be assigned poor outcome versus those possessing the C allele [CT/CC; odds of unfavorable GOS = 0.71(0.55-0.92)]. For ABCC1 rs4148382, patients homozygous for the G allele were less likely to be assigned poor outcome versus those possessing the A allele [AG/AA; odds of unfavorable GOS = 0.73(0.55-0.98)]. CONCLUSIONS: In this single-center study, patients homozygous for the T allele of ABCB1 rs1045642 or the G allele of ABCC1 rs4148382 were found to have better outcome after severe TBI. Further study is necessary to replicate these very preliminary findings and to determine whether these associations are due to central nervous system bioavailability of ABC transporter drug substrates commonly used in the management of TBI, brain efflux of endogenous solutes, or both.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Lesiones Encefálicas/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Adolescente , Adulto , Anciano , Barrera Hematoencefálica/fisiología , Lesiones Encefálicas/metabolismo , Femenino , Escala de Coma de Glasgow , Homocigoto , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Polimorfismo de Nucleótido Simple , Recuperación de la Función/genética , Adulto Joven
11.
RSC Adv ; 13(30): 20651-20662, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37435386

RESUMEN

This work reports on the integration of ZnO pellets for use as a virtual sensor array (VSA) of volatile organic compounds (VOCs). ZnO pellets consist of nano-powder prepared using a sol-gel technique. The microstructure of the obtained samples was characterized by XRD and TEM methods. The response to VOCs at different concentrations was measured over a range of operating temperatures (250-450 °C) using DC electrical characterization. The ZnO based sensor showed a good response towards ethanol, methanol, isopropanol, acetone and toluene vapors. We note that the highest sensitivity (0.26 ppm-1) is obtained with ethanol while the lowest one (0.041 ppm-1) corresponds to methanol. Consequently, the limit of detection (LOD) estimated analytically reached 0.3 ppm for ethanol and 2.0 ppm for methanol at an operating temperature of 450 °C. The sensing mechanism of the ZnO semiconductor was developed on the basis of the reaction between the reducing VOCs with the chemisorbed oxygen. We verify through the Barsan model that mainly O- ions in the layer react with VOC vapor. Furthermore, dynamic response was investigated to construct mathematical features with distinctly different values for each vapor. Basic linear discrimination analysis (LDA) shows a good job of separating two groups by combining features. In the same way we have shown an original reason embodying the distinction between more than two volatile compounds. With relevant features and VSA formalism, the sensor is clearly selective towards individual VOCs.

12.
RSC Adv ; 13(32): 21852-21860, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37475757

RESUMEN

Titanium dioxide (TiO2) thin films were deposited on glass substrates at 350 °C using the spray pyrolysis technique. As deposited and annealed thin films were characterized by X-ray diffraction, scanning electron microscopy, UV-VIS spectroscopy, and photodetection. Unlike the as deposited samples which were amorphous, annealed samples show an anatase phase. Films were absorbent in the UV region and the band gap energy decreases from 3.78 eV to 3.4 eV with annealing. The photoresponse of TiO2 photodetectors was recorded under UV (λ1 = 365 nm, λ2 = 254 nm) and visible light illumination by reversible switching (ON/OFF) cycles using DC electrical characterization. Photosensitive properties such as reproducible photosensitivity, responsivity, and detectivity were also studied.

13.
Gene Ther ; 19(12): 1177-86, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22170344

RESUMEN

Electrotransfer of plasmid DNA in skeletal muscle is a common non-viral delivery method for both therapeutic genes and DNA vaccines. Yet, despite the similar approaches, an immune response is detrimental in gene therapy, but desirable for vaccines. However, the full nature of the immune and tissue responses to nucleic acids and electrotransfer in skeletal muscle has not been addressed. Here we used microarray analysis, fluorescence-activated cell sorting and quantitative polymerase chain reaction to obtain the molecular and cellular signature of the tissue and immune response to electrotransfer of saline and non-coding plasmid DNA. Saline electrotransfer resulted in limited infiltration and induction of a moderate damage-repair gene expression pattern not involving innate immune activation. However, plasmid electrotransfer augmented expression of the same genes in addition to inducing a strong innate immune response associated with pro-inflammatory infiltration. In particular, the inflammasome, Toll-like receptor 9 and other pattern recognition receptors able to respond to cytoplasmic DNA were upregulated. Several key differences in the nature of the inflammatory infiltrate and the kinetics of gene expression were also identified when comparing electrotransfer of conventional and CpG-free plasmids. Our data provide insights into the mechanisms of DNA detection and response in muscle that has relevance for non-viral gene therapy and DNA vaccination.


Asunto(s)
Electroporación/métodos , Terapia Genética , Inmunidad Innata , Músculo Esquelético/metabolismo , Animales , Masculino , Ratones , Plásmidos , Receptor Toll-Like 9/genética , Transcriptoma
14.
Eur Cell Mater ; 24: 18-28, 2012 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-22777950

RESUMEN

Transplantation of mesenchymal stem cells (MSCs) with electrotransferred bone morphogenetic protein-2 (BMP-2) transgene is an attractive therapeutic modality for the treatment of large bone defects: it provides both stem cells with the ability to form bone and an effective bone inducer while avoiding viral gene transfer. The objective of the present study was to determine the influence of the promoter driving the human BMP-2 gene on the level and duration of BMP-2 expression after transgene electrotransfer into rat MSCs. Cytomegalovirus, elongation factor-1α, glyceraldehyde 3-phosphate dehydrogenase, and beta-actin promoters resulted in a BMP-2 secretion rate increase of 11-, 78-, 66- and 36-fold over respective controls, respectively. In contrast, the osteocalcin promoter had predictable weak activity in undifferentiated MSCs but induced the strongest BMP-2 secretion rates in osteoblastically-differentiated MSCs. Regardless of the promoter driving the transgene, a plateau of maximal BMP-2 secretion persisted for at least 21 d after the hBMP-2 gene electrotransfer. The present study demonstrates the feasibility of gene electrotransfer for efficient BMP-2 transgene delivery into MSCs and for a three-week sustained BMP-2 expression. It also provides the first in vitro evidence for a safe alternative to viral methods that permit efficient BMP-2 gene delivery and expression in MSCs but raise safety concerns that are critical when considering clinical applications.


Asunto(s)
Proteína Morfogenética Ósea 2/genética , Expresión Génica , Operón Lac , Osteocalcina/genética , Animales , Proteína Morfogenética Ósea 2/metabolismo , Huesos/citología , Huesos/fisiología , Diferenciación Celular , Células Cultivadas , Electroporación , Técnicas de Transferencia de Gen , Humanos , Masculino , Células Madre Mesenquimatosas , Ratones , Osteocalcina/metabolismo , Plásmidos , Regiones Promotoras Genéticas , Ratas , Ratas Endogámicas Lew , Factores de Tiempo , Transgenes
15.
J Cell Biol ; 143(6): 1575-89, 1998 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-9852152

RESUMEN

Glutamylation is the major posttranslational modification of neuronal and axonemal tubulin and is restricted predominantly to centrioles in nonneuronal cells (Bobinnec, Y., M. Moudjou, J.P. Fouquet, E. Desbruyères, B. Eddé, and M. Bornens. 1998. Cell Motil. Cytoskel. 39:223-232). To investigate a possible relationship between the exceptional stability of centriole microtubules and the compartmentalization of glutamylated isoforms, we loaded HeLa cells with the monoclonal antibody GT335, which specifically reacts with polyglutamylated tubulin. The total disappearance of the centriole pair was observed after 12 h, as judged both by immunofluorescence labeling with specific antibodies and electron microscopic observation of cells after complete thick serial sectioning. Strikingly, we also observed a scattering of the pericentriolar material (PCM) within the cytoplasm and a parallel disappearance of the centrosome as a defined organelle. However, centriole disappearance was transient, as centrioles and discrete centrosomes ultimately reappeared in the cell population. During the acentriolar period, a large proportion of monopolar half-spindles or of bipolar spindles with abnormal distribution of PCM and NuMA were observed. However, as judged by a quasinormal increase in cell number, these cells likely were not blocked in mitosis. Our results suggest that a posttranslational modification of tubulin is critical for long-term stability of centriolar microtubules. They further demonstrate that in animal cells, centrioles are instrumental in organizing centrosomal components into a structurally stable organelle.


Asunto(s)
Ciclo Celular/fisiología , Centriolos/fisiología , Centrosoma/fisiología , Microtúbulos/fisiología , Tubulina (Proteína)/metabolismo , Animales , Anticuerpos Monoclonales/farmacología , División Celular , Línea Celular , Centriolos/ultraestructura , Centrosoma/ultraestructura , Técnica del Anticuerpo Fluorescente Indirecta , Ácido Glutámico/metabolismo , Células HeLa , Humanos , Cinética , Metafase , Microscopía Electrónica , Microtúbulos/ultraestructura , Mitosis , Fosforilación , Procesamiento Proteico-Postraduccional , Vertebrados
16.
Mol Biotechnol ; 43(2): 167-76, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19562526

RESUMEN

About 25 years after the publication of the first report on gene transfer in vitro in cultured cells by the means of electric pulses delivery, reversible cell electroporation for gene transfer and gene therapy (DNA electrotransfer) is at a cross in its development. Present knowledge on the effects of cell exposure to appropriate electric field pulses, particularly at the level of the cell membrane, is reported here. The importance of the models of electric field distribution in tissues and of the correct choice of electrodes and applied voltages is highlighted. The mechanisms involved in DNA electrotransfer, which include cell electropermeabilization and DNA electrophoresis, are also surveyed. This knowledge has allowed developing new nucleic acids electrotransfer conditions using combinations of permeabilizing pulses of high voltage and short duration, and of electrophoretic pulses of low voltage and long duration, which are very efficient and safer. Feasibility of electric pulses delivery for gene transfer in humans is discussed taking into account that electric pulses delivery is already regularly used for localized drug delivery in the treatment of cutaneous and subcutaneous solid tumors by electrochemotherapy. Because recent technological developments made DNA electrotransfer more and more efficient and safer, this non-viral gene therapy approach is now ready to reach the clinical stage. A good understanding of DNA electrotransfer principles and the respect of safe procedures will be key elements for a successful future transfer DNA electrotransfer into the clinics.


Asunto(s)
Electroporación/métodos , Electroporación/tendencias , Terapia Genética/métodos , Terapia Genética/tendencias , Ácidos Nucleicos/genética , Transfección/métodos , Transfección/tendencias , Animales , Predicción , Humanos
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 134-137, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31945862

RESUMEN

When investigating the biophysical effects induced by the interaction between electromagnetic fields and biological cells, it is crucial to estimate the electromagnetic field intensity at the microscopic scale (microdosimetry). This information allows to find a connection between the external applied field and the observed biological event required to establish related biomedical applications. Here, authors present a microdosimetric study based on a 2D realistic model of a cell and its endoplasmic reticulum. The microdosimetric analysis of the cell and endoplasmic reticulum was quantified in terms of electric field and transmembrane potential induced by an externally applied high amplitude 10-ns pulsed electric field. In addition, electroporated local membrane sites and pore densities were also evaluated. This study opens the way to numerically assist experimental applications of nanosecond pulsed electric fields for controlled bio-manipulation of cells and subcellular organelles.


Asunto(s)
Retículo Endoplásmico , Membrana Celular , Campos Electromagnéticos , Electroporación , Potenciales de la Membrana
18.
Gene Ther ; 15(7): 537-44, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18256695

RESUMEN

Gene electrotransfer is an efficient and reproducible nonviral gene transfer technique useful for the nonpermanent expression of therapeutic transgenes. The present study established optimal conditions for the electrotransfer of reporter genes into mesenchymal stem cells (MSCs) isolated from rat bone marrow by their selective adherence to tissue-culture plasticware. The electrotransfer of the lacZ reporter gene was optimized by adjusting the pulse electric field intensity, electric pulse type, electropulsation buffer conductivity and electroporation temperature. LacZ electrotransfection into MSCs was optimal at 1500 V cm(-1) with pre-incubation in Spinner's minimum essential medium buffer at 22 degrees C. Under these conditions beta-galactosidase expression was achieved in 29+/-3% of adherent cells 48 h post transfection. The kinetics of beta-galactosidase activity revealed maintenance of beta-galactosidase production for at least 10 days. Moreover, electroporation did not affect the MSC potential for multidifferentiation; electroporated MSCs differentiated into osteoblastic, adipogenic and chondrogenic lineages to the same extent as cells that were not exposed to electric pulses. Thus, this study demonstrates the feasibility of efficient transgene electrotransfer into MSCs while preserving cell viability and multipotency.


Asunto(s)
Electroporación/métodos , Terapia Genética/métodos , Células Madre Mesenquimatosas/metabolismo , Animales , Técnicas de Cultivo de Célula , Diferenciación Celular , Células Cultivadas , Expresión Génica , Operón Lac , Masculino , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Ratas , Ratas Endogámicas Lew , Temperatura , Factores de Tiempo , Transfección/métodos , Transgenes , beta-Galactosidasa/genética
19.
Gene Ther ; 15(21): 1436-45, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18548116

RESUMEN

Given as a prophylactic treatment, a single muscle electrogene transfer of plasmid coding canstatin fused to human serum albumin (CanHSA), slowed down the development of two xenografted human carcinomas from mammary (MDA-MB-231) and prostate origin (PC-3) in nude mice and delayed lung metastatic spreading of B16F10 melanoma cells in syngenic mice. No effect was observed with unfused canstatin. The long lasting circulating blood level of CanHSA (20 ng ml(-1)) resulted in a profound disorganization of the tumor blood vessel network. However, when used as a curative treatment, on well-established tumors, CanHSA electrogenetherapy was ineffective in reducing tumor growth. As radiation is known to increase the alpha v beta3 and alpha v beta5 integrins, which are canstatin receptors, to extend the use of CanHSA electrogenetherapy, as a curative treatment, we explored the combination of CanHSA and ionizing radiation. We demonstrated a better efficacy (P=0.01) of the bitherapy over irradiation alone, as a result of strong vessel disorganization and dramatic increase of tumor cells apoptosis. This extremely simple virus free curative protocol could open the door to potential clinical applications, especially for prostate cancer that often develops radioresistance.


Asunto(s)
Neoplasias de la Mama/terapia , Colágeno Tipo IV/genética , Terapia Genética/métodos , Fragmentos de Péptidos/genética , Neoplasias de la Próstata/terapia , Proteínas Recombinantes de Fusión/uso terapéutico , Animales , Apoptosis , Neoplasias de la Mama/radioterapia , Línea Celular Tumoral , Colágeno Tipo IV/sangre , Terapia Combinada , Electroporación , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Músculo Esquelético/metabolismo , Fragmentos de Péptidos/sangre , Neoplasias de la Próstata/radioterapia , Dosificación Radioterapéutica , Proteínas Recombinantes de Fusión/genética , Albúmina Sérica/genética , Ensayos Antitumor por Modelo de Xenoinjerto
20.
J Vet Intern Med ; 22(4): 826-31, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18537879

RESUMEN

Electropermeabilization is a method that uses electric field pulses to induce an electrically mediated reorganization of the plasma membrane of cells. Electrochemotherapy combines local or systemic administration of chemotherapeutic drugs such as bleomycin or cisplatin that have poor membrane permeability with electropermeabilization by direct application of electric pulses to the tumors. Preclinical studies have demonstrated excellent antitumor effectiveness of electrochemotherapy on different animal models and various tumor types, minimal toxicity, and safety of the procedure. Based on results of preclinical studies, clinical studies were conducted in human patients, which demonstrated pronounced antitumor effectiveness of electrochemotherapy with 80-85% objective responses of the treated cutaneous and SC tumors. Clinical studies in veterinary oncology have demonstrated that electrochemotherapy is very effective in the treatment of cutaneous and SC tumors of different histologic types in cats, dogs, and horses. The results of these studies have also demonstrated approximately 80% long-lasting objective responses of tumors treated by electrochemotherapy. Primary tumors of different histologic types were treated. Electrochemotherapy in veterinary oncology has future promise to be highly effective, and could be used to treat primary or recurrent solitary or multiple cutaneous and SC tumors of different histology or as an adjuvant treatment to surgery.


Asunto(s)
Electroquimioterapia/métodos , Electroquimioterapia/veterinaria , Neoplasias/terapia , Neoplasias/veterinaria , Enfermedades de los Animales/terapia , Animales , Electroquimioterapia/instrumentación , Humanos
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