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1.
Anal Chem ; 95(40): 14853-14860, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37753614

RESUMEN

Oxidative processes in all types of organisms cause the chemical formation of electronically excited species, with subsequent ultraweak photon emission termed biological auto(chemi)luminescence (BAL). Imaging this luminescence phenomenon using ultrasensitive devices could potentially enable monitoring of oxidative stress in optically accessible areas of the human body, such as skin. Although oxidative stress induced by UV light has been explored, for chemically induced stress, there is no in vivo-quantified imaging of oxidative processes in human skin using BAL under the controlled extent of oxidative stress conditions. Furthermore, the mechanisms and dynamics of BAL from the skin have not been fully explored. Here, we demonstrate that different degrees of chemically induced oxidative stress on the skin can be spatially resolved quantitatively through noninvasive label-free BAL imaging. Additionally, to gain insight into the underlying mechanisms, a minimal chemical model of skin based on a mixture of lipid, melanin, and water was developed and used to show that it can be used to reproduce essential features of the response of real skin to oxidative stress. Our results contribute to novel, noninvasive photonic label-free methods for quantitative sensing of oxidative processes and oxidative stress.


Asunto(s)
Luminiscencia , Piel , Humanos , Piel/metabolismo , Estrés Oxidativo , Rayos Ultravioleta , Fotones
2.
Mikrochim Acta ; 190(11): 442, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37847341

RESUMEN

Electrochemical methods can be used not only for the sensitive analysis of proteins but also for deeper research into their structure, transport functions (transfer of electrons and protons), and sensing their interactions with soft and solid surfaces. Last but not least, electrochemical tools are useful for investigating the effect of an electric field on protein structure, the direct application of electrochemical methods for controlling protein function, or the micromanipulation of supramolecular protein structures. There are many experimental arrangements (modalities), from the classic configuration that works with an electrochemical cell to miniaturized electrochemical sensors and microchip platforms. The support of computational chemistry methods which appropriately complement the interpretation framework of experimental results is also important. This text describes recent directions in electrochemical methods for the determination of proteins and briefly summarizes available methodologies for the selective labeling of proteins using redox-active probes. Attention is also paid to the theoretical aspects of electron transport and the effect of an external electric field on the structure of selected proteins. Instead of providing a comprehensive overview, we aim to highlight areas of interest that have not been summarized recently, but, at the same time, represent current trends in the field.


Asunto(s)
Técnicas Electroquímicas , Proteínas , Electroquímica , Oxidación-Reducción , Transporte de Electrón , Técnicas Electroquímicas/métodos
3.
Int J Biometeorol ; 65(1): 59-67, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32335726

RESUMEN

Mechanisms of how electromagnetic (EM) field acts on biological systems are governed by the same physics regardless of the origin of the EM field (technological, atmospheric...), given that EM parameters are the same. We draw from a large body of literature of bioeffects of a man-made electromagnetic field. In this paper, we performed a focused review on selected possible mechanisms of how atmospheric electromagnetic phenomena can act at the molecular and cellular level. We first briefly review the range of frequencies and field strengths for both electric and magnetic fields in the atmosphere. Then, we focused on a concise description of the current knowledge on weak electric and magnetic field bioeffects with possible molecular mechanisms at the basis of possible EM field bioeffects combined with modeling strategies to estimate reliable outcomes and speculate about the biological effects linked to lightning or pyroelectricity. Indeed, we bring pyroelectricity as a natural source of voltage gradients previously unexplored. While very different from lightning, it can result in similar bioeffects based on similar mechanisms, which can lead to close speculations on the importance of these atmospheric electric fields in the evolution.


Asunto(s)
Electricidad , Campos Electromagnéticos , Campos Electromagnéticos/efectos adversos , Humanos
4.
Int J Biometeorol ; 65(1): 107-117, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32198562

RESUMEN

The term neurodegenerative diseases include a long list of diseases affecting the nervous system that are characterized by the degeneration of different neurological structures. Among them, Alzheimer disease (AD), Parkinson disease (PD), and amyotrophic lateral sclerosis (ALS) are the most representative ones. The vast majority of cases are sporadic and results from the interaction of genes and environmental factors in genetically predisposed individuals. Among environmental conditions, electromagnetic field exposure has begun to be assessed as a potential risk factor for neurodegeneration. In this review, we discuss the existing literature regarding electromagnetic fields and neurodegenerative diseases. Epidemiological studies in AD, PD, and ALS have shown discordant results; thus, a clear correlation between electromagnetic exposure and neurodegeneration has not been demonstrated. In addition, we discuss the role of electromagnetic radiation as a potential non-invasive therapeutic strategy for some neurodegenerative diseases, particularly for PD and AD.


Asunto(s)
Enfermedad de Alzheimer , Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Enfermedad de Alzheimer/epidemiología , Esclerosis Amiotrófica Lateral/epidemiología , Campos Electromagnéticos , Humanos , Enfermedades Neurodegenerativas/epidemiología
5.
Int J Biometeorol ; 65(1): 45-58, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32666310

RESUMEN

The atmosphere is host to a complex electric environment, ranging from a global electric circuit generating fluctuating atmospheric electric fields to local lightning strikes and ions. While research on interactions of organisms with their electrical environment is deeply rooted in the aquatic environment, it has hitherto been confined to interactions with local electrical phenomena and organismal perception of electric fields. However, there is emerging evidence of coupling between large- and small-scale atmospheric electrical phenomena and various biological processes in terrestrial environments that even appear to be tied to continental waters. Here, we synthesize our current understanding of this connectivity, discussing how atmospheric electricity can affect various levels of biological organization across multiple ecosystems. We identify opportunities for research, highlighting its complexity and interdisciplinary nature and draw attention to both conceptual and technical challenges lying ahead of our future understanding of the relationship between atmospheric electricity and the organization and functioning of biological systems.


Asunto(s)
Ecosistema , Electricidad , Atmósfera
6.
Int J Biometeorol ; 65(1): 5-29, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33025117

RESUMEN

There is an increasing interest to study the interactions between atmospheric electrical parameters and living organisms at multiple scales. So far, relatively few studies have been published that focus on possible biological effects of atmospheric electric and magnetic fields. To foster future work in this area of multidisciplinary research, here we present a glossary of relevant terms. Its main purpose is to facilitate the process of learning and communication among the different scientific disciplines working on this topic. While some definitions come from existing sources, other concepts have been re-defined to better reflect the existing and emerging scientific needs of this multidisciplinary and transdisciplinary area of research.


Asunto(s)
Biología , Electricidad
7.
Phys Biol ; 15(3): 031002, 2018 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-29205173

RESUMEN

This roadmap outlines the role semiconductor-based materials play in understanding the complex biophysical dynamics at multiple length scales, as well as the design and implementation of next-generation electronic, optoelectronic, and mechanical devices for biointerfaces. The roadmap emphasizes the advantages of semiconductor building blocks in interfacing, monitoring, and manipulating the activity of biological components, and discusses the possibility of using active semiconductor-cell interfaces for discovering new signaling processes in the biological world.


Asunto(s)
Comunicación Celular/fisiología , Polímeros/química , Semiconductores , Propiedades de Superficie
8.
Ann Bot ; 122(5): 757-766, 2018 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-29300820

RESUMEN

Background: A brief review is given of Peter W. Barlows' contributions to research on gravity tide-related phenomena in plant biology, or 'selenonastic' effects as he called them, including his early research on root growth. Also, new results are presented here from long-term recordings of spontaneous ultra-weak light emission during germination, reinforcing the relationship between local lunisolar tidal acceleration and seedling growth. Scope: The main ideas and broad relevance of the work by Barlow and his collaborators about the effects of gravity on plants are reviewed, highlighting the necessity of new models to explain the apparent synchronism between root growth and microscale gravity changes 107 times lower than that exerted by the Earth's gravity. The new results, showing for the first time the germination of coffee beans in sequential tests over 2 months, confirm the co-variation between the patterns in ultra-weak light emission and the lunisolar tidal gravity curves for the initial growth phase. For young sprouts (<1 month old), the rhythm of growth as well as variation in light emission exhibit the once a day and twice a day periodic variations, frequency components that are the hallmark of local lunisolar gravimetric tides. Although present, this pattern is less pronounced in coffee beans older than 1 month. Conclusions: The apparent co-variation between ultra-weak light emission and growth pattern in coffee seedlings and the lunisolar gravity cycles corroborate those previously found in seedlings from other species. It is proposed here that such patterns may attenuate with time for older sprouts with slow development. These data suggest that new models considering both intra- and intercellular interactions are needed to explain the putative sensing and reaction of seedlings to the variations in the gravimetric tide. Here, a possible model is presented based on supracellular matrix interconnections.


Asunto(s)
Coffea/fisiología , Germinación/fisiología , Gravitación , Luz , Fenómenos Fisiológicos de las Plantas , Historia del Siglo XX , Historia del Siglo XXI
9.
J Biol Phys ; 42(1): 1-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26174548

RESUMEN

The knowledge of mechanisms underlying interactions between biological systems, be they biomacromolecules or living cells, is crucial for understanding physiology, as well as for possible prevention, diagnostics and therapy of pathological states. Apart from known chemical and direct contact electrical signaling pathways, electromagnetic phenomena were proposed by some authors to mediate non-chemical interactions on both intracellular and intercellular levels. Here, we discuss perspectives in the research of nanoscale electromagnetic interactions between biosystems on radiofrequency and microwave wavelengths. Based on our analysis, the main perspectives are in (i) the micro and nanoscale characterization of both passive and active radiofrequency properties of biomacromolecules and cells, (ii) experimental determination of viscous damping of biomacromolecule structural vibrations and (iii) detailed analysis of energetic circumstances of electromagnetic interactions between oscillating polar biomacromolecules. Current cutting-edge nanotechnology and computational techniques start to enable such studies so we can expect new interesting insights into electromagnetic aspects of molecular biophysics of cell signaling.


Asunto(s)
Microondas , Radiobiología/métodos , Sustancias Macromoleculares/metabolismo
10.
Data Brief ; 52: 109765, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38370023

RESUMEN

We present trajectories from non-equilibrium (in electric field) molecular dynamics (MD) simulations of a kinesin motor domain on tubulin heterodimers with two tubulin heterodimers forming neighbouring microtubule protofilaments. The trajectories are for no field (long equilibrium simulation), for four different electric field orientations (X, -X, Y, -Y) and for the X electric field at four different field strengths. We also provide a trajectory for larger simulation box. Our data enable to analyze the electric field effects on kinesin, which ultimately leads to kinesin detachment. This data set was used to understand the effect of electric field orientation and field strength on the kinetics and energetics of the electro-detachment of kinesin [1].

11.
J Phys Chem Lett ; 15(32): 8334-8342, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39110643

RESUMEN

Many proteins are thought to coordinate distant sites in their structures through a concerted action of global structural vibrations. However, the direct experimental spectroscopic detection of these vibration modes is rather elusive. We used normal-mode analysis to explore the dominant vibration modes of an all-atom model of the tubulin protein and described their characteristics using a large ensemble of tubulin structures. We quantified the frequency range of the normal vibrational modes to be in the subterahertz band, specifically between ∼40 and ∼160 GHz. Adding water layers to the model increases the frequencies of the low-frequency modes and narrows the frequency variations of the modes among the protein ensemble. We also showed how the electromagnetic absorption of tubulin vibration modes is affected by vibrational damping. These results contribute to our understanding of tubulin's vibrational and electromagnetic properties and provide a foundation for future attempts to control protein behavior via external electromagnetic fields.

12.
Biotechnol J ; 19(4): e2300475, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38651262

RESUMEN

The application of pulsed electric fields (PEFs) is becoming a promising tool for application in biotechnology, and the food industry. However, real-time monitoring of the efficiency of PEF treatment conditions is challenging, especially at the industrial scale and in continuous production conditions.  To overcome this challenge, we have developed a straightforward setup capable of real-time detection of yeast biological autoluminescence (BAL) during pulsing. Saccharomyces cerevisiae culture was exposed to 8 pulses of 100 µs width with electric field strength magnitude 2-7 kV cm-1. To assess the sensitivity of our method in detecting yeast electroporation, we conducted a comparison with established methods including impedance measurements, propidium iodide uptake, cell growth assay, and fluorescence microscopy. Our results demonstrate that yeast electroporation can be instantaneously monitored during pulsing, making it highly suitable for industrial applications. Furthermore, the simplicity of our setup facilitates its integration into continuous liquid flow systems. Additionally, we have established quantitative indicators based on a thorough statistical analysis of the data that can be implemented through a dedicated machine interface, providing efficiency indicators for analysis.


Asunto(s)
Electroporación , Saccharomyces cerevisiae , Saccharomyces cerevisiae/crecimiento & desarrollo , Electroporación/métodos
13.
Cell Commun Signal ; 11: 87, 2013 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-24219796

RESUMEN

Despite the large number of reports attributing the signaling between detached cell cultures to the electromagnetic phenomena, almost no report so far included a rigorous analysis of the possibility of such signaling.In this paper, we examine the physical feasibility of the electromagnetic communication between cells, especially through light, with regard to the ambient noise illumination. We compare theoretically attainable parameters of communication with experimentally obtained data of the photon emission from cells without a specially pronounced ability of bioluminescence.We show that the weak intensity of the emission together with an unfavorable signal-to-noise ratio, which is typical for natural conditions, represent an important obstacle to the signal detection by cells.


Asunto(s)
Comunicación Celular , Fenómenos Electromagnéticos , Luz , Transducción de Señal , Fotones , Probabilidad , Relación Señal-Ruido
14.
Prog Biophys Mol Biol ; 177: 80-108, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36336139

RESUMEN

Biological oxidation processes are in the core of life energetics, play an important role in cellular biophysics, physiological cell signaling or cellular pathophysiology. Understanding of biooxidation processes is also crucial for biotechnological applications. Therefore, a plethora of methods has been developed for monitoring oxidation so far, each with distinct advantages and disadvantages. We review here the available methods for monitoring oxidation and their basic characteristics and capabilities. Then we focus on a unique method - the only one that does not require input of additional external energy or chemicals - which employs detection of biological autoluminescence (BAL). We highlight the pros and cons of this method and provide an overview of how BAL can be used to report on various aspects of cellular oxidation processes starting from oxygen consumption to the generation of oxidation products such as carbonyls. This review highlights the application potential of this completely non-invasive and label-free biophotonic diagnostic method.


Asunto(s)
Estrés Oxidativo , Oxidación-Reducción
15.
Comput Struct Biotechnol J ; 21: 1349-1361, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36814722

RESUMEN

Kinesin is a motor protein essential in cellular functions, such as intracellular transport and cell-division, as well as for enabling nanoscopic transport in bio-nanotechnology. Therefore, for effective control of function for nanotechnological applications, it is important to be able to modify the function of kinesin. To circumvent the limitations of chemical modifications, here we identify another potential approach for kinesin control: the use of electric forces. Using full-atom molecular dynamics simulations (247,358 atoms, total time ∼ 4.4 µs), we demonstrate, for the first time, that the kinesin-1 motor domain can be detached from a microtubule by an intense electric field within the nanosecond timescale. We show that this effect is field-direction dependent and field-strength dependent. A detailed analysis of the electric forces and the work carried out by electric field acting on the microtubule-kinesin system shows that it is the combined action of the electric field pulling on the ß-tubulin C-terminus and the electric-field-induced torque on the kinesin dipole moment that causes kinesin detachment from the microtubule. It is shown, for the first time in a mechanistic manner, that an electric field can dramatically affect molecular interactions in a heterologous functional protein assembly. Our results contribute to understanding of electromagnetic field-biomatter interactions on a molecular level, with potential biomedical and bio-nanotechnological applications for harnessing control of protein nanomotors.

16.
Methods Mol Biol ; 2430: 61-70, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35476325

RESUMEN

Microtubules composed of tubulin heterodimers represent highly dynamic structures. These structures are essential for basic cellular functions, such as cell division. Microtubules can grow or shrink in response to environmental signals, principally chemical cues. Here, we provide an alternative-physical-strategy to modulate tubulin properties and its self-assembly process. The conformation and electrical properties of tubulin subunits are modulated by nanosecond electropulse signals. The formed structures of electrically treated tubulin are tightly linked to the degree of conformational and electrical properties changes induced by nanosecond electropulses. This strategy opens a new way for controlling the self-assembly process in biomolecules as well as in bioinspired materials.


Asunto(s)
Microtúbulos , Tubulina (Proteína) , Electricidad , Microtúbulos/metabolismo , Estructura Cuaternaria de Proteína , Tubulina (Proteína)/metabolismo
17.
Sci Rep ; 12(1): 2462, 2022 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-35165315

RESUMEN

Pulsed electric field (PEF) technology is promising for the manipulation of biomolecular components and has potential applications in biomedicine and bionanotechnology. Microtubules, nanoscopic tubular structures self-assembled from protein tubulin, serve as important components in basic cellular processes as well as in engineered biomolecular nanosystems. Recent studies in cell-based models have demonstrated that PEF affects the cytoskeleton, including microtubules. However, the direct effects of PEF on microtubules are not clear. In this work, we developed a lab-on-a-chip platform integrated with a total internal reflection fluorescence microscope system to elucidate the PEF effects on a microtubules network mimicking the cell-like density of microtubules. The designed platform enables the delivery of short (microsecond-scale), high-field-strength ([Formula: see text] 25 kV/cm) electric pulses far from the electrode/electrolyte interface. We showed that microsecond PEF is capable of overcoming the non-covalent microtubule bonding force to the substrate and translocating the microtubules. This microsecond PEF effect combined with macromolecular crowding led to aggregation of microtubules. Our results expand the toolbox of bioelectronics technologies and electromagnetic tools for the manipulation of biomolecular nanoscopic systems and contribute to the understanding of microsecond PEF effects on a microtubule cytoskeleton.

18.
Eur Biophys J ; 40(6): 747-59, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21394502

RESUMEN

This paper describes a proposed biophysical mechanism of a novel diagnostic method for cancer detection developed recently by Vedruccio. The diagnostic method is based on frequency selective absorption of electromagnetic waves by malignant tumors. Cancer is connected with mitochondrial malfunction (the Warburg effect) suggesting disrupted physical mechanisms. In addition to decreased energy conversion and nonutilized energy efflux, mitochondrial malfunction is accompanied by other negative effects in the cell. Diminished proton space charge layer and the static electric field around the outer membrane result in a lowered ordering level of cellular water and increased damping of microtubule-based cellular elastoelectrical vibration states. These changes manifest themselves in a dip in the amplitude of the signal with the fundamental frequency of the nonlinear microwave oscillator-the core of the diagnostic device-when coupled to the investigated cancerous tissue via the near-field. The dip is not present in the case of healthy tissue.


Asunto(s)
Biofisica/métodos , Campos Electromagnéticos , Microtúbulos/efectos de la radiación , Neoplasias/diagnóstico , Neoplasias/patología , Biofisica/instrumentación , Estudios de Casos y Controles , Elasticidad , Electricidad , Humanos , Microtúbulos/química , Microtúbulos/metabolismo , Microondas , Neoplasias/metabolismo , Vibración , Agua/química , Agua/metabolismo
19.
J Integr Neurosci ; 10(1): 65-88, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21425483

RESUMEN

In this paper we argue that, in addition to electrical and chemical signals propagating in the neurons of the brain, signal propagation takes place in the form of biophoton production. This statement is supported by recent experimental confirmation of photon guiding properties of a single neuron. We have investigated the interaction of mitochondrial biophotons with microtubules from a quantum mechanical point of view. Our theoretical analysis indicates that the interaction of biophotons and microtubules causes transitions/fluctuations of microtubules between coherent and incoherent states. A significant relationship between the fluctuation function of microtubules and alpha-EEG diagrams is elaborated on in this paper. We argue that the role of biophotons in the brain merits special attention.


Asunto(s)
Membrana Celular/metabolismo , Fenómenos Electromagnéticos , Microtúbulos/metabolismo , Mitocondrias/metabolismo , Fotones , Animales , Membrana Celular/química , Electroencefalografía/métodos , Humanos , Microtúbulos/química , Mitocondrias/química , Transducción de Señal/fisiología
20.
Sci Rep ; 11(1): 10852, 2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34035342

RESUMEN

Nowadays, modern medicine is looking for new, more gentle, and more efficient diagnostic methods. A pathological state of an organism is often closely connected with increased amount of reactive oxygen species. They can react with biomolecules and subsequent reactions can lead to very low endogenous light emission (biological autoluminescence-BAL). This phenomenon can be potentially used as a non-invasive and low-operational-cost tool for monitoring oxidative stress during diseases. To contribute to the understanding of the parameters affecting BAL, we analyzed the BAL from yeast Saccharomyces cerevisiae as a representative eukaryotic organism. The relationship between the BAL intensity and the amount of reactive oxygen species that originates as a result of the Fenton reaction as well as correlation between spontaneous BAL and selected physical and chemical parameters (pH, oxygen partial pressure, and cell concentration) during cell growth were established. Our results contribute to real-time non-invasive methodologies for monitoring oxidative processes in biomedicine and biotechnology.


Asunto(s)
Especies Reactivas de Oxígeno/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Mediciones Luminiscentes , Oxidación-Reducción , Saccharomyces cerevisiae/metabolismo
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