Abstract:
:In adherent and motile neutrophils NAD(P)H concentration, flavoprotein redox potential, and production of reactive oxygen species and nitric oxide, are all periodic and exhibit defined phase relationships to an underlying metabolic oscillation of approximately 20 s. Utilizing fluorescence microscopy, we have shown in real-time, on the single cell level, that the system is sensitive to externally applied periodically pulsed weak magnetic fields matched in frequency to the metabolic oscillation. Depending upon the phase relationship of the magnetic pulses to the metabolic oscillation, the magnetic pulses serve to either increase the amplitude of the NAD(P)H and flavoprotein oscillations, and the rate of production of reactive oxygen species and nitric oxide or, alternatively, collapse the metabolic oscillations and curtail production of reactive oxygen species and nitric oxide. Significantly, we demonstrate that the cells do not directly respond to the magnetic fields, but instead are sensitive to the electric fields which the pulsed magnetic fields induce. These weak electric fields likely tap into an endogenous signaling pathway involving calcium channels in the plasma membrane. We estimate that the threshold which induced electric fields must attain to influence cell metabolism is of the order of 10(-4) V/m.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Rosenspire AJ,Kindzelskii AL,Simon BJ,Petty HRdoi
10.1529/biophysj.104.056663subject
Has Abstractpub_date
2005-05-01 00:00:00pages
3334-47issue
5eissn
0006-3495issn
1542-0086pii
S0006-3495(05)73383-Xjournal_volume
88pub_type
杂志文章abstract::Halobacterium halobium contains at least three retinal-containing pigments: bacteriorhodopsin, halorhodopsin, and a third rhodopsin-like pigment (tR) absorbing at approximately 590 nm, tR590. Illumination of tR590 gives rise to a very long-lived blue absorbing photoproduct, tR370. Using high-performance liquid chromat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83969-2
更新日期:1985-05-01 00:00:00
abstract::The activity of the voltage-gated Na+ channel is subjected to modulation through covalent modifications. It has been previously shown that brain Na+ currents are reduced following the activation of the protein kinase A (PKA) pathway, but the effect of the phosphorylation on the gating mechanism of the channel has not ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)76882-7
更新日期:1999-07-01 00:00:00
abstract::A useful technique in studying the saturation of hemoglobin in erythrocytes or myoglobin in tissue is cryophotometry, in which tissue is frozen for later spectrophotometric analysis. A general question associated with this technique is whether the freezing process alters the chemical state. This paper presents a theor...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84365-3
更新日期:1983-04-01 00:00:00
abstract::We showed recently that the high-salt transition of poly[d(G-C)]. poly[d(G-C)] between B-DNA and Z-DNA (at [NaCl] = 2.25 M or [MgCl(2)] = 0.7 M) can be ascribed to the lesser electrostatic free energy of the B form, due to better immersion of the phosphates in the solution. This property was incorporated in cylindrica...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(00)76665-3
更新日期:2000-02-01 00:00:00
abstract::The thermal stability of a Schizolobium parahyba chymotrypsin inhibitor (SPCI) as a function of pH has been investigated using fluorescence, circular dichroism, and differential scanning calorimetry (DSC). The thermodynamic parameters derived from all methods are remarkably similar and strongly suggest the high stabil...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.045682
更新日期:2005-05-01 00:00:00
abstract::Actin is one of the main components of the architecture of cells. Actin filaments form different polymer networks with versatile mechanical properties that depend on their spatial organization and the presence of cross-linkers. Here, we investigate the mechanical properties of actin bundles in the absence of cross-lin...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.07.017
更新日期:2017-09-05 00:00:00
abstract::We have constructed a model of the upper part of the glycolysis in the pancreatic beta-cell. The model comprises the enzymatic reactions from glucokinase to glyceraldehyde-3-phosphate dehydrogenase (GAPD). Our results show, for a substantial part of the parameter space, an oscillatory behavior of the glycolysis for a ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74460-9
更新日期:2003-07-01 00:00:00
abstract::The patch-clamp technique of Mueller (1975, Ann. N.Y. Acad. Sci., 274:247-264) and Neher and Sakmann (1976, Nature (Lond.), 260:799-802) was modified to be suitable for single-channel measurements in lipid bilayers at potentials up to 500 mV. This method was used to study gramicidin A single-channel current-voltage ch...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84414-2
更新日期:1983-02-01 00:00:00
abstract::Sodium perchlorate salt (NaClO(4)) is commonly used as an internal intensity standard in ultraviolet resonance Raman (UVRR) spectroscopy experiments. It is well known that NaClO(4) can have profound effects on peptide stability. The impact of NaClO(4) on protein stability in UVRR experiments has not yet been fully inv...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.10.013
更新日期:2010-01-20 00:00:00
abstract::We present a probability density approach to modeling localized Ca2+ influx via L-type Ca2+ channels and Ca2+-induced Ca2+ release mediated by clusters of ryanodine receptors during excitation-contraction coupling in cardiac myocytes. Coupled advection-reaction equations are derived relating the time-dependent probabi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.099861
更新日期:2007-04-01 00:00:00
abstract::The resonance Raman spectrum of the second intermediate in the bacteriorhodopsin cycle, bL550, is obtained by a simple flow technique. The Schiff base linkage in this intermediate appears to be protonated, contrary to previous suggestion. The fingerprint region of the spectrum of bL550 does not closely match those of ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(79)85269-8
更新日期:1979-06-01 00:00:00
abstract::Many organs adapt to their mechanical environment as a result of physiological change or disease. Cells are both the detectors and effectors of this process. Though many studies have been performed in vitro to investigate the mechanisms of detection and adaptation to mechanical strains, the cellular strains remain unk...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75214-4
更新日期:2002-08-01 00:00:00
abstract::Detection of the transition between the two myosin isoforms α- and β-myosin in living cardiomyocytes is essential for understanding cardiac physiology and pathology. In this study, the differences in symmetry of polarization spectra obtained from α- and β-myosin in various mammalian ventricles and propylthiouracil-tre...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.12.030
更新日期:2020-03-10 00:00:00
abstract::Conventional equations for enzyme kinetics are based on mass-action laws, that may fail in low-dimensional and disordered media such as biological membranes. We present Monte Carlo simulations of an isolated Michaelis-Menten enzyme reaction on two-dimensional lattices with varying obstacle densities, as models of biol...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)73953-2
更新日期:2002-10-01 00:00:00
abstract::We have constructed a theory for diffusion through the pore of a single-ion channel by taking a limit of a random walk around a cycle of states. Similar to Levitt's theory of single-ion diffusion, one obtains boundary conditions for the Nernst-Planck equation that guarantee that the pore is occupied by at most one ion...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79374-8
更新日期:1996-10-01 00:00:00
abstract::The proteorhodopsin family consists of retinal proteins of marine bacterial origin with optical properties adjusted to their local environments. For green proteorhodopsin, a highly specific mutation in the EF loop, A178R, has been found to cause a surprisingly large redshift of 20 nm despite its distance from the chro...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.06.014
更新日期:2013-07-16 00:00:00
abstract::A discrete multistate kinetic model for water-wire proton transport is constructed and analyzed using Monte Carlo simulations. In the model, each water molecule can be in one of three states: oxygen lone-pairs pointing leftward, pointing rightward, or protonated (H(3)O(+)). Specific rules for transitions among these s...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(04)74335-0
更新日期:2004-05-01 00:00:00
abstract::The analysis of peptide and protein partitioning in lipid membranes is of high relevance for the understanding of biomembrane function. We used statistical thermodynamics analysis to demonstrate the effect of peptide mixing behavior on heat capacity profiles of lipid membranes with the aim to predict peptide aggregati...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)75047-4
更新日期:2003-04-01 00:00:00
abstract::Quantitative characterization of protein interactions under physiological conditions is vital for systems biology. Fluorescence photobleaching/activation experiments of GFP-tagged proteins are frequently used for this purpose, but robust analysis methods to extract physicochemical parameters from such data are lacking...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.071241
更新日期:2006-03-15 00:00:00
abstract::Identifying the basic module of enzymatic amplification as an irreversible cycle of messenger activation/deactivation by a "push-pull" pair of opposing enzymes, we analyze it in terms of gain, bandwidth, noise, and power consumption. The enzymatic signal transduction cascade is viewed as an information channel, the de...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76519-2
更新日期:2000-12-01 00:00:00
abstract::We have determined directly the effects of the inhibitory peptide phospholamban (PLB) on the rotational dynamics of the calcium pump (Ca-ATPase) of cardiac sarcoplasmic reticulum (SR). This was accomplished by comparing mouse ventricular SR, which has PLB levels similar to those found in other mammals, with mouse atri...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80355-3
更新日期:1995-05-01 00:00:00
abstract::The influence of electrostatic multipole moments up to hexadecapole on the dynamics of photodissociated carbon monoxide (CO) in myoglobin is investigated. The CO electrostatic potential is expressed as an expansion into atomic multipole moments of increasing order up to octopole which are obtained from a distributed m...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.120519
更新日期:2008-04-01 00:00:00
abstract::A new stable substrate applicable to the observation of DNA molecules by atomic force microscopy (AFM) was fabricated from a ultrasmooth sapphire (alpha-Al2O3 single crystal) plate. The atomically ultrasmooth sapphire as obtained by high-temperature annealing has hydrophobic surfaces and could not be used for the AFM ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77878-6
更新日期:1998-04-01 00:00:00
abstract::Sedimentation velocity is a powerful tool for the analysis of complex solutions of macromolecules. However, sample turbidity imposes an upper limit to the size of molecular complexes currently amenable to such analysis. Furthermore, the breadth of the particle size distribution, combined with possible variations in th...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77273-5
更新日期:1999-02-01 00:00:00
abstract::Effects of alkali cations on the nuclear magnetic resonance intensity of 23Na were studied in rat liver homogenate. The loss in the resonance intensity of 23Na in the homogenate was able to be divided into two components, one of which is abolished by the addition of Cs+ ("Cs-sensitive component"), the other being inse...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(76)85779-7
更新日期:1976-12-01 00:00:00
abstract::Two T = 1 and one T = 3 plant viruses, along with a protein, were crystallized in microgravity during the International Microgravity Laboratory-2 (IML-2) mission in July of 1994. The method used was liquid-liquid diffusion in the European Space Agency's Advanced Protein Crystallization Facility (APCF). Distinctive alt...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79890-3
更新日期:1995-07-01 00:00:00
abstract::Single-particle tracking is an important technique in the life sciences to understand the kinetics of biomolecules. The analysis of apparent diffusion coefficients in vivo, for example, enables researchers to determine whether biomolecules are moving alone, as part of a larger complex, or are bound to large cellular c...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.09.033
更新日期:2020-11-17 00:00:00
abstract::How do Ca channels conduct Ca ions during the cardiac action potential? We attempt to answer this question by applying a two-microelectrode technique, previously used for Na and K currents, in which we record the patch current and the action potential at the same time (Mazzanti, M., and L. J. DeFelice. 1987. Biophys. ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82448-6
更新日期:1990-10-01 00:00:00
abstract::The increasingly widespread use of parametric mathematical models to describe biological systems means that the ability to infer model parameters is of great importance. In this study, we consider parameter inferability in nonlinear ordinary differential equation models that undergo a bifurcation, focusing on a simple...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.126086
更新日期:2008-07-01 00:00:00
abstract::The interaction of Phormidium laminosum plastocyanin (PC) with P. laminosum cytochrome f (cyt f) was studied using Brownian dynamics (BD) simulations. Few complexes and a low rate of electron transfer were observed for wild-type PC. Increasing the positive electrostatic field on PC by the addition of a Zn(2+) ion in t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.103.038497
更新日期:2004-09-01 00:00:00