Abstract:
:The pulling of micropipette electrodes from glass tubing has been treated as a problem of viscous flow coupled with the Newtonian dynamics of the pulling apparatus. Analytical solutions are given from which the taper profile, tip diameter, and pulling time can be obtained. The physical principles of operation of micropipette pullers are discussed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Purves RDdoi
10.1016/S0006-3495(80)85150-2subject
Has Abstractpub_date
1980-03-01 00:00:00pages
523-9issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(80)85150-2journal_volume
29pub_type
杂志文章abstract::Using a recently developed in vitro motility assay, we have demonstrated that local anesthetics directly inhibit myosin-based movement of single actin filaments in a reversible dose-dependent manner. This is the first reported account of the actions of local anesthetics on purified proteins at the molecular level. In ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79466-3
更新日期:1996-11-01 00:00:00
abstract::Two modes of behavior of single human red cells in a shear field have been described. It is known that in low viscosity media and at shear rates less than 20 s-1, the cells rotate with a periodically varying angular velocity, in accord with the theory of Jeffery (1922) for oblate spheroids. In media of viscosity great...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(86)83734-1
更新日期:1986-05-01 00:00:00
abstract::Hundreds of cationic antimicrobial and cell-penetrating peptides (CPPs) form amphipathic α-helices when bound to lipid membranes. Here, we test two hypotheses for the differences in the ability of these peptides to translocate across membranes. The first, which we now call the hydrophobicity hypothesis, is that peptid...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.08.047
更新日期:2016-10-18 00:00:00
abstract::PROPPINs (β-propellers that bind polyphosphoinositides) are a family of PtdIns3P- and PtdIns(3,5)P2-binding proteins that play an important role in autophagy. We analyzed PROPPIN-membrane binding through isothermal titration calorimetry (ITC), stopped-flow measurements, mutagenesis studies, and molecular dynamics (MD)...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.03.045
更新日期:2015-05-05 00:00:00
abstract::The engulfment function of macrophages relies on complex molecular interactions involving both lipids and proteins. In particular, the clearance of apoptotic bodies (efferocytosis) is enabled by externalization on the cell target of phosphatidylserine lipids, which activate receptors on macrophages, suggesting that (l...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.12.036
更新日期:2014-02-04 00:00:00
abstract::The E5 oncoprotein is the major transforming protein of bovine papillomavirus type 1. This 44-residue transmembrane protein can interact with the platelet-derived growth factor receptor β, leading to ligand-independent activation and cell transformation. For productive interaction, E5 needs to dimerize via a C-termina...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.06.073
更新日期:2010-09-22 00:00:00
abstract::Solubility plays a major role in protein purification, and has serious implications in many diseases. We studied the effects of pH and mutations on protein solubility by calculating the transfer free energy from the condensed phase to the solution phase. The condensed phase was modeled as an implicit solvent, with a d...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.127746
更新日期:2008-09-15 00:00:00
abstract::Odorant-induced currents in mammalian olfactory receptor neurons have proved difficult to obtain reliably using conventional whole-cell recording. By using a mathematical model of the electrical circuit of the patch and rest-of-cell, we demonstrate how cell-attached patch measurements can be used to quantitatively ana...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78791-5
更新日期:1997-03-01 00:00:00
abstract::Alamethicin is a 19-residue hydrophobic peptide, which is extended by a C-terminal phenylalaninol but lacks residues that might anchor the ends of the peptide at the lipid-water interface. Voltage-dependent ion channels formed by alamethicin depend strongly in their characteristics on chain length of the host lipid me...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.104026
更新日期:2007-06-01 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
abstract::Phosphorescence spectroscopy on mouse myeloma IgA J539 in rigid solution at 77K revealed the type of anomalous short-lived component in the tryptophan decay originally observed with lysozyme (Churchich, J.E., 1966. Biochim. Biophys. Acta. 120:406-412) and seen in a large number of Bence Jones proteins (Longworth, J.W....
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(89)82681-5
更新日期:1989-08-01 00:00:00
abstract::Melittin has been reported to form toroidal pores under certain conditions, but the atomic-resolution structure of these pores is unknown. A 9-μs all-atom molecular-dynamics simulation starting from a closely packed transmembrane melittin tetramer in DMPC shows formation of a toroidal pore after 1 μs. The pore remains...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.04.006
更新日期:2015-05-19 00:00:00
abstract::The dynamics of proton transfer between the surface of purple membrane and the aqueous bulk have recently been investigated by the Laser Induced Proton Pulse Method. Following a Delta-function release of protons to the bulk, the system was seen to regain its state of equilibrium within a few hundreds of microseconds. ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74887-5
更新日期:2003-01-01 00:00:00
abstract::The crystal structure of the RNA octamer, 5'-GGCGUGCC-3' has been determined from x-ray diffraction data to 1.5 angstroms resolution. In the crystal, this oligonucleotide forms five self-complementary double-helices in the asymmetric unit. Tandem 5'GU/3'UG basepairs comprise an internal loop in the middle of each dupl...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.081018
更新日期:2006-06-15 00:00:00
abstract::We examined the effects of brief current pulses on the pacemaker oscillations of the Purkinje fiber using the model of McAllister , Noble, and Tsien (1975. J. Physiol. [Lond.]. 251:1-57). This model was used to construct phase-response curves for brief electric stimuli to find "black holes," where rhythmic activity of...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(84)84228-9
更新日期:1984-04-01 00:00:00
abstract::We describe a statistical technique, the joint peristimulus time (PST) scatter diagram, for the analysis of data from simultaneously recorded neurons subjected to repeated stimulation. Distinguishable features in the scatter diagram are related to effects of the stimulus on the observed neurons and to functional relat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(72)86097-1
更新日期:1972-05-01 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::Structural rearrangements of the myosin upper-50 kD subdomain are thought to play a key role in coordinating actin binding with nucleotide hydrolysis during the myosin ATPase cycle. Such rearrangements could open and close the active site in opposition to the actin-binding cleft, helping explain the opposing affinitie...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.059840
更新日期:2005-09-01 00:00:00
abstract::The pathway to membrane fusion in synthetic and biological systems is thought to pass through hemifusion, in which the outer leaflets are fused while the inner leaflets engage in a hemifusion diaphragm (HD). Fusion has been proposed to be completed by lysis of the expanded HD that matures from a localized stalklike in...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.06.041
更新日期:2012-08-22 00:00:00
abstract::The following arguments are presented for the observation that curves relating free Ca2+ and force development of thin filament regulated myofilaments of skinned muscle fibers have Hill coefficient (n) greater than 4, which is the number of Ca2+ binding sites on troponin: Activation of the myofilaments is a process re...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(84)84051-5
更新日期:1984-10-01 00:00:00
abstract::The fluorescent Mg(2+) indicator furaptra (mag-fura-2) was introduced into single ventricular myocytes by incubation with its acetoxy-methyl ester form. The ratio of furaptra's fluorescence intensity at 382 and 350 nm was used to estimate the apparent cytoplasmic [Mg(2+)] ([Mg(2+)](i)). In Ca(2+)-free extracellular co...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.055517
更新日期:2005-03-01 00:00:00
abstract::We have performed molecular dynamics simulations of multiple copies of the lung-surfactant peptide SP-B1-25 in a palmitic acid (PA) monolayer. SP-B1-25 is a shorter version of lung-surfactant protein B, an important component of lung surfactant. Up to 30 ns simulations of 20 wt % SP-B1-25 in the PA monolayers were per...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.066241
更新日期:2005-12-01 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::Skeletal and heart muscle excitability is based upon the pool of available sodium channels as determined by both fast and slow inactivation. Slow inactivation in hH1 sodium channels significantly differs from slow inactivation in hSkM1. The beta(1)-subunit modulates fast inactivation in human skeletal sodium channels ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)76987-0
更新日期:1999-09-01 00:00:00
abstract::Endophilins are SH3- and BAR domain-containing proteins implicated in membrane remodeling and vesicle formation. Endophilins A1 and A2 promote the budding of endocytic vesicles from the plasma membrane, whereas endophilin B1 has been implicated in vesicle budding from intracellular organelles, including the trans-Golg...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.06.017
更新日期:2016-08-09 00:00:00
abstract::The ability to discriminate between different cations efficiently is essential for the proper physiological functioning of many membrane transport proteins. One obvious mechanism of ion selectivity is when a binding site is structurally constrained by the protein architecture and its geometry is precisely adapted to f...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.03.038
更新日期:2010-06-16 00:00:00
abstract::The depth of insertion of an antimicrobial peptide, protegrin-1 (PG-1), in lipid bilayers is investigated using solid-state NMR. Paramagnetic Mn(2+) ions bind to the surface of lipid bilayers and induce distance-dependent dipolar relaxation of nuclear spins. By comparing the signal dephasing of the peptide with that o...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74660-8
更新日期:2003-10-01 00:00:00
abstract::Muscle contraction occurs as the result of actin-myosin interaction, which is mediated by the intermolecular forces exerted at the actin-myosin interface. To obtain information about the nature of these intermolecular forces, we tested the sensitivity of various contractile parameters of skinned skeletal muscle fibers...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76850-0
更新日期:2000-06-01 00:00:00
abstract::In previous in vivo studies, amyloid fibers formed from a peptide ubiquitous in human seminal fluid (semen-derived enhancer of viral infection (SEVI)) were found to dramatically enhance the infectivity of the HIV virus (3-5 orders of magnitude by some measures). To complement those studies, we performed in vitro assay...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.08.034
更新日期:2009-11-04 00:00:00
abstract::Noncanonical DNA structures that retain programmability and structural predictability are increasingly being used in DNA nanotechnology applications, in which they offer versatility beyond traditional Watson-Crick interactions. The d(CGA) triplet repeat motif is structurally dynamic and can transition between parallel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.09.002
更新日期:2020-10-20 00:00:00