Abstract:
:Calculations are reported of the time-dependent Nernst-Planck equations for a thin permeable membrane between electrolytic solutions. Charge neutrality is assumed for the time-dependent case. The response of such a membrane system to step current input is measured in terms of the time and space changes in concentration, electrical potential, and effective conductance. The report also includes discussion of boundary effects that occur when charge neutrality does not hold in the steady-state case.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
COHEN H,COOLEY JWdoi
10.1016/s0006-3495(65)86707-8subject
Has Abstractpub_date
1965-03-01 00:00:00pages
145-62eissn
0006-3495issn
1542-0086pii
S0006-3495(65)86707-8journal_volume
5pub_type
杂志文章abstract::An innovative method is presented to measure the mechanical driving point impedance of biological structures up to at least 40 kHz. The technique employs an atomic force cantilever with a ferromagnetic coating and an external magnetic field to apply a calibrated force to the cantilever. Measurement of the resulting ca...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.103.037184
更新日期:2004-08-01 00:00:00
abstract::The structure of polymer-decorated phospholipid monolayers at the solid-solution interface was investigated using neutron reflectometry. The monolayers were composed of distearoylphosphatidylethanolamine (DSPE) matrixed with varying amounts of DSPE-PEG (DSPE with polyethylene glycol covalently grafted to its headgroup...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77679-9
更新日期:1998-11-01 00:00:00
abstract::Fluorescence resonance energy transfer (FRET) was used to reveal aspects of the mechanism of signal transduction by epidermal growth factor receptors (EGFR). The superpositions of epidermal growth factor (EGF), transforming growth factor-alpha (TGFalpha) and an antibody fragment (29.1) to the carbohydrate extremity of...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75585-9
更新日期:2002-05-01 00:00:00
abstract::Evidence that the fluorophore sempervirene binds to nucleic acids is presented. The complexes were studied by fluorescence intensity, spectra, decay lifetime, and polarization methods. Both fluorescent and nonfluorescent complexes are formed. The sempervirene is rigidly fixed to DNA. If ethidium bromide and sempervire...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(74)85906-0
更新日期:1974-03-01 00:00:00
abstract::A growth cone is a motile structure at the tips of axons that is driven by the actin network and guides axon extension. Low actin adhesion to the substrate creates a stationary actin treadmill that allows leading-edge protrusion when adhesion increases in response to guidance cues. We use experimental measurements in ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.03.003
更新日期:2012-04-04 00:00:00
abstract::Drug-membrane interactions are well known but poorly understood. Here we describe dual measurements of membrane thickness change and membrane area change due to the binding of the amphipathic drug curcumin. The combined results allowed us to analyze the binding states of a drug to lipid bilayers, one on the water-memb...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.133736
更新日期:2008-09-01 00:00:00
abstract::We show prolonged contraction of permeabilized muscle fibers of the frog during which structural order, as judged from low-angle x-ray diffraction, was preserved by means of partial cross-linking of the fibers using the zero-length cross-linker 1-ethyl-3-[3-dimethylamino)propyl]carbodiimide. Ten to twenty percent of t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79347-5
更新日期:1996-09-01 00:00:00
abstract::In two-color fluorescence correlation spectroscopy (TCFCS), the fluorescence intensities of two fluorescently-labeled species are cross-correlated over time and can be used to identify static and dynamic interactions. Generally, fluorophore labels are chosen that do not undergo Förster resonance energy transfer (FRET)...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75189-8
更新日期:2002-07-01 00:00:00
abstract::A new general method for the determination of electrostatic potentials at biological surfaces is presented. The approach is based on measurement of the collision frequency of a charged nitroxide in solution with a nitroxide fixed to the surface at the point of interest. The collision frequency is determined with 14N:1...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81950-1
更新日期:1992-06-01 00:00:00
abstract::We present a single virion method to determine absolute distributions of copy number in the protein composition of viruses and apply it to herpes simplex virus type 1. Using two-color coincidence fluorescence spectroscopy, we determine the virion-to-virion variability in copy numbers of fluorescently labeled tegument ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.106351
更新日期:2007-08-15 00:00:00
abstract::O-acetylserine sulfhydrylase, a homo-dimeric enzyme from Salmonella typhimurium, covalently binds one pyridoxal 5'-phosphate molecule per subunit as a fluorescent coenzyme. Different tautomers of the Schiff base between the coenzyme and lysine 41 generate structured absorption and fluorescence spectra upon one-photon ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76167-X
更新日期:2001-04-01 00:00:00
abstract::Total internal reflection (TIR) microfluorimetry was established as a method to measure continuously the volume of adherent cells and applied to measure membrane permeabilities in cells transfected with water channel homologs. Cytosol was labeled with the membrane-impermeant fluorophore calcein. Fluorescence was excit...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80335-8
更新日期:1995-04-01 00:00:00
abstract::We have used the elastic neutron scattering technique to investigate the dynamics of the two main saccharidic components of starch: amylose and amylopectin. The measurements were carried out in the temperature range of 20 to 320 K and at different hydration levels from the dry state up to 0.47 g saccharide/g D(2)O. In...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75776-1
更新日期:2001-08-01 00:00:00
abstract::The role played by non-homogeneous interactions in stabilizing cooperative structural changes in proteins was investigated by exhaustive simulations of all compact conformations compatible with several well-defined globule-like shapes in three dimensions. Conformational free energies corresponding to the association o...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(94)80798-2
更新日期:1994-02-01 00:00:00
abstract::Atherosclerosis is a disease initiated by lipoprotein aggregation and deposition in artery walls. In this study, the de novo low-density lipoprotein aggregation process was examined. Nine major intermediates were identified in two stages of the aggregation process. In the aggregation stage, low-density lipoprotein mol...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75887-0
更新日期:2001-10-01 00:00:00
abstract::We have attempted to link the solution actomyosin ATPase with the mechanical properties of in vitro actin filament sliding over heavy meromyosin. To accomplish this we perturbed the system by altering the substrate with various NTPs and divalent cations, and by altering ionic strength. A wide variety of enzymatic and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76022-5
更新日期:2001-01-01 00:00:00
abstract::We present an analysis of physical chemical constraints on the accuracy of DNA micro-arrays under equilibrium and nonequilibrium conditions. At the beginning of the article we describe an algorithm for choosing a probe set with high specificity for targeted genes under equilibrium conditions. The algorithm as well as ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74837-1
更新日期:2003-01-01 00:00:00
abstract::Two monocysteine mutants of cardiac muscle troponin C, cTnC(C35S) and cTnC(C84S), were genetically generated and labeled with the fluorescent probe 2-[4'-(iodoacetamido)anilino]naphthalene-6-sulfonic acid (IAANS) at Cys-84 and Cys-35, respectively. Cys-84 is located on helix D in the regulatory N-domain, and Cys-35 is...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(97)78719-8
更新日期:1997-02-01 00:00:00
abstract::Unlike most transmembrane proteins, phospholipids can migrate from one leaflet of the membrane to the other. Because this spontaneous lipid translocation (flip-flop) tends to be very slow, cells facilitate the process with enzymes that catalyze the transmembrane movement and thereby regulate the transbilayer lipid dis...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.01.016
更新日期:2019-03-05 00:00:00
abstract::Protein solubility in aqueous solutions depends in a complicated and not well understood way on pH, salt type, and salt concentration. Why for instance does the use of two different monovalent salts, potassium thiocyanate and potassium chloride, produce such different results? One important and previously neglected so...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74512-3
更新日期:2003-08-01 00:00:00
abstract::The structure and dynamics of soluble misfolded aggregates are poorly understood, despite their importance in protein science and disease. Water-soluble self-associated species that do not become insoluble over time are invaluable tools for high-resolution conformational studies aimed at dissecting the determinants of...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.12.3722
更新日期:2011-02-02 00:00:00
abstract::The design and implementation of a high-speed, random-access, laser-scanning fluorescence microscope configured to record fast physiological signals from small neuronal structures with high spatiotemporal resolution is presented. The laser-scanning capability of this nonimaging microscope is provided by two orthogonal...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78086-X
更新日期:1997-07-01 00:00:00
abstract::The structure of the unusually long (∼100 amino-acid residues) N-terminal domain of the light-harvesting protein CP29 of plants is not defined in the crystal structure of this membrane protein. We studied the N-terminus using two electron paramagnetic resonance (EPR) approaches: the rotational diffusion of spin labels...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.11.4506
更新日期:2014-03-18 00:00:00
abstract::Formation of liquid-ordered domains in model membranes can be linked to raft formation in cellular membranes. The lipid stoichiometry has a governing influence on domain formation and consequently, biochemical hydrolysis of specific lipids has the potential to remodel domain features. Activation of phospholipase A(2) ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.114363
更新日期:2008-05-15 00:00:00
abstract::The earliest event in exocytosis is the formation of a fusion pore, an aqueous channel that connects the lumen of a secretory granule with the extracellular space. We can observe the formation of individual fusion pores and their subsequent dilation or closure by measuring the changes in the admittance of patch-clampe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81884-2
更新日期:1992-03-01 00:00:00
abstract::Neal and Cunningham (Neal, M. J., and J. R. Cunningham. 1995. J. Physiol. (Lond.). 482:363-372) showed that GABA(B) agonists and glycinergic antagonists enhance the light-evoked release of retinal acetylcholine. They proposed that glycinergic cells inhibit the cholinergic Starburst amacrine cells and are in turn inhib...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.072256
更新日期:2006-07-15 00:00:00
abstract::The potassium selective, inward rectifier current (IK1) is known to be responsible for maintaining the resting membrane potential of quiescent ventricular myocytes. However, the contribution of this current to the different phases of the cardiac action potential has not been adequately established. In the present stud...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82187-7
更新日期:1991-12-01 00:00:00
abstract::Trimethylamine-N-oxide (TMAO) in the cells of sharks and rays is believed to counteract the deleterious effects of the high intracellular concentrations of urea in these animals. It has been hypothesized that TMAO has the generic ability to counteract the effects of urea on protein structure and function, regardless o...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77972-X
更新日期:1998-05-01 00:00:00
abstract::We develop a model of tyrosine phosphorylation and activation of the T-cell receptor (TCR) by localization to regions of close membrane-membrane proximity (close contact) that physically exclude tyrosine phosphatases such as CD45. Phosphatase exclusion generates regions of low phosphatase and high kinase activity and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.080044
更新日期:2006-09-01 00:00:00
abstract::Neutron scattering and nuclear magnetic resonance relaxation experiments are combined with molecular dynamics (MD) simulations in a novel, to our knowledge, approach to investigate the change in internal dynamics on substrate (camphor) binding to a protein (cytochrome P450cam). The MD simulations agree well with both ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.10.013
更新日期:2012-11-21 00:00:00