Abstract:
:We modeled two different mechanisms, a shunting conductance and a slow sodium inactivation, to test whether they could modulate the active propagation of a train of action potentials in a dendritic tree. Computer simulations, using a compartmental model of a pyramidal neuron, suggest that each of these two mechanisms could account for the activity-dependent attenuation and failure of the action potentials in the dendrites during the train. Each mechanism is shown to be in good qualitative agreement with experimental findings on somatic or dendritic stimulation and on the effects of hyperpolarization. The conditions under which branch point failures can be observed, and a few experimentally testable predictions, are presented and discussed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Migliore Mdoi
10.1016/S0006-3495(96)79433-Xsubject
Has Abstractpub_date
1996-11-01 00:00:00pages
2394-403issue
5eissn
0006-3495issn
1542-0086pii
S0006-3495(96)79433-Xjournal_volume
71pub_type
杂志文章abstract::We have used optical tweezers to study the elasticity of red cell membranes; force was applied to a bead attached to a permeabilized spherical ghost and the force-extension relation was obtained from the response of a second bead bound at a diametrically opposite position. Interruption of the skeletal network by disso...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77139-0
更新日期:1999-12-01 00:00:00
abstract::Despite the importance of magnetic properties of biological samples for biomagnetism and related fields, the exact magnetic susceptibilities of most biological samples in their physiological conditions are still unknown. Here we used superconducting quantum interferometer device to detect the magnetic properties of no...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.12.020
更新日期:2020-02-04 00:00:00
abstract::Catch bonds are characterized by average lifetimes that initially increase with increasing tensile force. Recently, they have been implicated in T cell activation, where small numbers of antigenic receptor-ligand bonds at a cell-cell interface can stimulate a T cell. Here, we use computational methods to investigate s...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.05.023
更新日期:2017-07-11 00:00:00
abstract::The structure of the Bowman-Birk inhibitor from Vigna unguiculata seeds (BTCI) in complex with beta-trypsin was solved and refined at 1.55 A to a crystallographic R(factor) of 0.154 and R(free) of 0.169, and represents the highest resolution for a Bowman-Birk inhibitor structure to date. The BTCI-trypsin interface is ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.090555
更新日期:2007-03-01 00:00:00
abstract::Ras is a membrane-anchored signaling protein that serves as a hub for many signaling pathways and also plays a prominent role in cancer. The intrinsic behavior of Ras on the membrane has captivated the biophysics community in recent years, especially the possibility that it may form dimers. In this article, we describ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.10.042
更新日期:2018-01-09 00:00:00
abstract::We present a qualitative computer graphics approach to the characterization of forces important to the assembly of beta domains that should have general utility for examining protein interactions and assembly. In our approach, the nature of the molecular surface buried by the domain contacts, the specificity of the re...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(86)83634-7
更新日期:1986-01-01 00:00:00
abstract::Electron paramagnetic resonance spectroscopy was used to monitor the orientation of muscle cross-bridges attached to actin in a low force and high stiffness state that may occur before force generation in the actomyosin cycle of interactions. 2,3-butanedione monoxime (BDM) has been shown to act as an uncompetitive inh...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80375-9
更新日期:1995-05-01 00:00:00
abstract::We have developed a method of performing near-field fluorescence correlation spectroscopy via an array of planarized circular apertures of 50 nm diameter. This technique provides 1 μs and 60 nm resolution on proximal samples, including live cells, without incorporating a scanning probe or pulsed lasers or requiring pe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.02.034
更新日期:2011-04-06 00:00:00
abstract::The distal side of the heme pocket, known to regulate ligand affinity, is shown to be directly involved in subunit interactions. Valency hybrids with oxygen or carbon monoxide bound to the reduced chain are used to model R-state hemoglobin with different distal perturbations. Electron paramagnetic resonance of the oxi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81879-9
更新日期:1992-03-01 00:00:00
abstract::BP100 (KKLFKKILKYL-NH(2)) is a short cecropin A-melittin hybrid peptide, obtained through a combinatorial chemistry approach, which is highly effective in inhibiting both the in vitro and in vivo growth of economically important plant pathogenic Gram-negatives. The intrinsic Tyr fluorescence of BP100 was taken advanta...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2008.11.053
更新日期:2009-03-04 00:00:00
abstract::Self-aggregation of isolated plant light-harvesting complexes (LHCs) upon detergent extraction is associated with fluorescence quenching and is used as an in vitro model to study the photophysical processes of nonphotochemical quenching (NPQ). In the NPQ state, in vivo induced under excess solar light conditions, harm...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.09.055
更新日期:2011-11-16 00:00:00
abstract::The fundamental backbone dynamics of unfolded proteins arising due to intrinsic ϕ-ψ dihedral angle fluctuations dictate the course of protein folding, binding, assembly, and function. These internal fluctuations are also critical for protein misfolding associated with a range of human diseases. However, direct observa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.07.023
更新日期:2016-08-23 00:00:00
abstract::Phenotypic plasticity is posed to be a vital trait of cancer cells such as circulating tumor cells, allowing them to undergo reversible or irreversible switching between phenotypic states important for tumorigenesis and metastasis. While irreversible phenotypic switching can be detected by studying the genome, reversi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.02.012
更新日期:2017-03-28 00:00:00
abstract::The three-dimensional structure of chromatin affects DNA accessibility and is therefore a key regulator of gene expression. However, the path of the DNA between consecutive nucleosomes, and the resulting chromatin fiber organization remain controversial. The conformational space available for the folding of the nucleo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.11.040
更新日期:2010-03-17 00:00:00
abstract::We investigate the permeability of lipid membranes for fluorescence dyes and ions. We find that permeability reaches a maximum close to the chain melting transition of the membranes. Close to transitions, fluctuations in area and compressibility are high, leading to an increased likelihood of spontaneous lipid pore fo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.01.062
更新日期:2009-06-03 00:00:00
abstract::The photoreceptor rhodopsin is a G-protein coupled receptor that has recently been proposed to exist as a dimer or higher order oligomer, in contrast to the previously described monomer, in retinal rod outer segment disk membranes. Rhodopsin exhibits considerably greater thermal stability than opsin (the bleached form...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.128868
更新日期:2008-09-15 00:00:00
abstract::We studied the cold unfolding of myoglobin with Fourier transform infrared spectroscopy and compared it with pressure and heat unfolding. Because protein aggregation is a phenomenon with medical as well as biotechnological implications, we were interested in both the structural changes as well as the aggregation behav...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75605-1
更新日期:2002-05-01 00:00:00
abstract::The effects of phosphorylation on the voltage-dependent properties of dihydropyridine-sensitive Ca channels of skeletal muscle were studied. Single channel currents were recorded upon incorporation of transverse tubule membranes into planar bilayers that were kept polarized at near physiological resting potential and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82124-5
更新日期:1991-10-01 00:00:00
abstract::Mechanical properties of living cells can be determined using atomic force microscopy (AFM). In this study, a novel analysis was developed to determine the mechanical properties of adherent monolayers of pulmonary microvascular endothelial cells (ECs) using AFM and finite element modeling, which considers both the fin...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.099333
更新日期:2008-04-15 00:00:00
abstract::Bases, nucleosides, nucleotides, and polynucleotides were exposed to chemically generated singlet oxygen to determine whether the species oxidized paralleled those oxidized in photodynamic reactions. In neutral or basic aqueous solution guanine, guanosine, deoxyguanosine, guanylic acid, deoxyguanylic acid, thymine, an...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(70)86303-2
更新日期:1970-04-01 00:00:00
abstract::A first principles model for calculating hydrogen bonding interactions, previously applied to water, is here applied to the more difficult problem of interactions between DNA bases. We first consider the energetics and geometry for the A-T and the G-C basepairs, comparing our results to other calculated results as wel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79980-5
更新日期:1995-09-01 00:00:00
abstract::Cryo-electron microscopy is rapidly emerging as a powerful technique to determine the structures of complex macromolecular systems elusive to other techniques. Because many of these systems are highly dynamical, characterizing their movements is also a crucial step to unravel their biological functions. To achieve thi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.02.028
更新日期:2018-04-10 00:00:00
abstract::Evidence is presented for the existence of two forms of low-potential cytochrome a3. One appears to be similar to the low-spin form reported by Nicholls, P., and V. Hildebrandt (1978 Biochem. J. 173:65-72) and Wrigglesworth, J. M., J. Elsden, A. Chapman, N. Van der Water, and M. F. Grahn (1988. Biochim. Biophys. Acta....
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82633-3
更新日期:1990-06-01 00:00:00
abstract::We report a method to profile the torsional spring properties of proteins as a function of the angle of rotation. The torque is applied by superparamagnetic particles and has been calibrated while taking account of the magnetization dynamics of the particles. We record and compare the torsional profiles of single Prot...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.01.027
更新日期:2013-03-05 00:00:00
abstract::Changes in the ultraviolet light scattering from a suspension of purple membrane fragments were detected during the photocycle of bacteriorhodopsin with a cross-correlation method. The scattered light intensity from a suspension of membrane fragments containing the protein bacteriorhodopsin was measured on a logarithm...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82415-2
更新日期:1990-09-01 00:00:00
abstract::The pKa values of ionizable groups that lie between the active site region of bacteriorhodopsin (bR) and the extracellular surface of the protein are reported. Glu-204 is found to have an elevated pKa in the resting state of bR, suggesting that it corresponds to the proton-releasing group in bR. Its elevated pKa is pr...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79320-7
更新日期:1996-09-01 00:00:00
abstract::The energy transfer processes between carotenoids and Chls have been studied by femtosecond transient absorption in the CP29-WT complex, which contains only two carotenoids per polypeptide located in the L1 and L2 sites, and in the CP29-E166V mutant in which only the L1 site is occupied. The comparison of these two sa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)75057-7
更新日期:2003-04-01 00:00:00
abstract::Deuterium wide line NMR spectroscopy was used to study cholesterol effects on the ceramide portions of two glycosphingolipids (GSLs) distributed as minor components in fluid membranes. The common existence of very long fatty acids on GSLs was taken into account by including one glycolipid species with fatty acid chain...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80173-6
更新日期:1995-01-01 00:00:00
abstract::We find evidence for a direct transition of insulin monomers into amyloid fibrils without measurable concentrations of oligomers or protofibrils, suggesting that fibrillogenesis may occur directly from assembly of denaturing insulin monomers rather than by successive transitions through protofibril nuclei. To support ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.10.010
更新日期:2010-12-15 00:00:00
abstract::Voltage-sensing dyes and voltage-sensing fluorescence proteins have been continually improved and as a result have provided a wealth of insights into neuronal circuits. Further improvements in voltage-sensing dyes and voltage-sensing fluorescence proteins are needed, however, for routine detection of single action pot...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.12.047
更新日期:2017-02-28 00:00:00