Abstract:
:The high gradient magnetic separation technique has been applied to separate paramagnetic erythrocytes from a cell suspension that also contained diamagnetic cells. Paramagnetism was induced in the red blood cells by oxidizing the iron atoms in the cell hemoglobin to the ferric state (methemoglobin). Diamagnetic cells were either untreated erythrocytes, containing oxyferrohemoglobin, or leukocytes in a suspension of mouse spleen cells. Cell suspensions were passed through a column containing 40 micron diameter stainless steel wire in a high magnetic field (33 kG). The paramagnetic cells were retained on the surface of the wire while the diamagnetic cells passed through. Elution of the paramagnetic cells was accomplished by removing the column from the magnet, in effect turning off the field.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Owen CSdoi
10.1016/S0006-3495(78)85482-4subject
Has Abstractpub_date
1978-05-01 00:00:00pages
171-8issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(78)85482-4journal_volume
22pub_type
杂志文章abstract::Two-color spatio-temporal image cross-correlation spectroscopy (STICCS) is a new, to our knowledge, image analysis method that calculates space-time autocorrelation and cross-correlation functions from fluorescence intensity fluctuations. STICCS generates cellular flow and diffusion maps that reveal interactions and c...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.08.060
更新日期:2012-10-17 00:00:00
abstract::The effect of antibodies to glycophorin A on the rotational diffusion of band 3 in human erythrocyte membranes was investigated by transient dichrosim. Three antibodies that recognize different epitopes on the exofacial domain of glycophorin A all strongly reduce the rotational mobility of band 3. The effect is at mos...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80365-6
更新日期:1995-05-01 00:00:00
abstract::Gap junction conductance (Gj) and channel gating sensitivity to voltage, Ca2+, H+, and heptanol were studied by double whole-cell clamp in Novikoff hepatoma cell pairs. Channel gating was observed at transjunctional voltages (Vj) > +/- 50 mV. The cells readily uncoupled with 1 mM 1-heptanol. With heptanol, single (gap...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81242-6
更新日期:1993-11-01 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::In biological applications of atomic force microscopy, the different surface properties of the biological sample and its support become apparent. Observed height differences between the biomolecule and its supporting surface are thus not only of structural origin, but also depend on the different sample-tip and suppor...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78195-5
更新日期:1997-09-01 00:00:00
abstract::The strength of receptor-mediated cell adhesion is directly controlled by the mechanism of cohesive failure between the cell surface and underlying substrate. Unbinding can occur either at the locus of the specific bond or within the bilayer, which results in tearing the hydrophobic anchors from the membrane interior....
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79990-8
更新日期:1995-09-01 00:00:00
abstract::Recent biological optical spectroscopic studies have correlated discrete spectroscopic states with biological function in several systems. One of the challenges of molecular biophysics is to correlate structural changes with these spectroscopic states. From small-angle x-ray scattering one can obtain a key structural ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(79)85252-2
更新日期:1979-05-01 00:00:00
abstract::Transport of large proteins into the nucleus involves two events, binding of the cargo protein to a transport receptor in the cytoplasm and passage of the cargo-transporter complex through the selective permeability barrier of the nuclear pore complex. The permeability barrier is formed by largely disordered polypepti...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.02.049
更新日期:2010-06-02 00:00:00
abstract::Closing linear poly(ethylene glycol) (PEG) into a circular "crown" dramatically changes its dynamics in the alpha-hemolysin channel. In the electrically neutral crown ether (C2H4O)6, six ethylene oxide monomers are linked into a circle that gives the molecule ion-complexing capacity and increases its rigidity. As with...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.044453
更新日期:2004-11-01 00:00:00
abstract::Previous data as well as new results are examined with a view to determining the boundary conditions which present experimental information places on a satisfactory polypeptide chain model for the structure of feather keratin. Our studies indicate these conditions to include the following: (1) A 189 A identity period,...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(61)86903-8
更新日期:1961-07-01 00:00:00
abstract::Relations describing threshold fluctuation phenomena in nerves are derived by calculating the approximate response of the Hodgkin-Huxley (HH) axon to electrical noise. We use FitzHugh's reduced phase space approximation and describe the dynamics of a noisy nerve by a two-dimensional brownian motion. The theory predict...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(71)86277-X
更新日期:1971-12-01 00:00:00
abstract::The molecular basis of the activation of G-proteins by the G-protein coupled receptor for parathyroid hormone (PTH) is unknown. Employing a combination of NMR methods and computer-based structural refinement, structural features involved in the activation of Galpha(s) by the PTH receptor (PTH1R) have been determined. ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.094813
更新日期:2007-01-15 00:00:00
abstract::Gigaohm recordings have been made from glutamate receptor channels in excised, outside-out patches of collagenase-treated locust muscle membrane. The channels in the excised patches exhibit the kinetic state switching first seen in megaohm recordings from intact muscle fibers. Analysis of channel dwell time distributi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82367-5
更新日期:1990-07-01 00:00:00
abstract::Molecular sensors based on intramolecular Förster resonance energy transfer (FRET) have become versatile tools to monitor regulatory molecules in living tissue. However, their use is often compromised by low signal strength and excessive noise. We analyzed signal/noise (SNR) aspects of spectral FRET analysis methods, ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.07.053
更新日期:2010-10-06 00:00:00
abstract::We have studied the photoinduced volume changes, energetics, and kinetics in the early steps of the bacteriorhodopsin (BR) photocycle with pulsed, time-resolved photoacoustics. Our data show that there are two volume changes. The fast volume change ( < or = 200 ns) is an expansion (2.5 +/- 0.3 A3/molecule) and is obse...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79235-4
更新日期:1996-07-01 00:00:00
abstract::Observation of cell membrane buckling and cell folding in micropipette aspiration experiments was used to evaluate the bending rigidity of the red blood cell membrane. The suction pressure required to buckle the membrane surface initially was found to be about one-half to two-thirds of the pressure that caused the cel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84319-7
更新日期:1983-07-01 00:00:00
abstract::This study aims to define the role of E-cadherin (Ecad) engagement in cell-cell contact during membrane-cortex interaction. As a tool, we used a hydrodynamic membrane tube extrusion technique to characterize the mechanical interaction between the plasma membrane and the underlying cortical cytoskeleton. Cells were anc...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2008.11.059
更新日期:2009-03-18 00:00:00
abstract::Sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA) and phospholamban (PLB) are essential for intracellular Ca2+ transport in myocytes. Ca2+-dependent activation of SERCA-PLB provides a control function that regulates cytosolic and SR Ca2+ levels. Although experimental and computational studies alone have led to a greater...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.09.014
更新日期:2020-11-03 00:00:00
abstract::Multiconformation membrane proteins are mechanosensitive (MS) if their conformations displace different bilayer areas. Might MS closed-closed transitions serve as tension buffers, that is, as membrane "spandex"? While bilayer expansion is effectively instantaneous, transitions of bilayer-embedded MS proteins are stoch...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.08.054
更新日期:2009-11-18 00:00:00
abstract::The mathematics of the binomial model for quantal neurotransmitter release is considered in general terms, to explore what information might be extractable from statistical aspects of data. For an array of N statistically independent release sites, each with a release probability p, the compound binomial always pertai...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(97)78709-5
更新日期:1997-02-01 00:00:00
abstract::Laser Raman spectroscopy has been used detect structural changes in troponin C induced by Ca2+ binding. Addition of Ca2+ - Mg2+ sites produces perturbations in the amide III region of the spectrum indicative of increased alpha-helical content, and in regions of the spectrum corresponding to carboxylate, thiol, and phe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(80)85099-5
更新日期:1980-05-01 00:00:00
abstract::The influence of patch electrode glass composition on macroscopic IV relations in inside-out patches of the cGMP-activated ion channel from rod photoreceptors was examined for a soda lime glass, a Kovar sealing glass, a borosilicate glass, and several soft lead glasses. In several glasses the shape or magnitude of the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(88)83091-1
更新日期:1988-02-01 00:00:00
abstract::Formation of low-temperature ordered gel phases in several fully hydrated phosphatidylethanolamines (PEs) and phosphatidylcholines (PCs) with saturated chains as well as in dipalmitoylphosphatidylglycerol (DPPG) was observed by synchrotron x-ray diffraction, microcalorimetry, and densitometry. The diffraction patterns...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76157-7
更新日期:2001-04-01 00:00:00
abstract::Cell adhesion to extracellular matrix is mediated by receptor-ligand interactions. When a cell first contacts a surface, it spreads, exerting traction forces against the surface and forming new bonds as its contact area expands. Here, we examined the changes in shape, actin polymerization, focal adhesion formation, an...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.054320
更新日期:2005-07-01 00:00:00
abstract::In permeabilized single fibers of fast (psoas) and slow (soleus) muscle from the rabbit, the effect of pH on isometric myofibrillar ATPase activity and force was studied at 15 degrees C, in the pH range 6.4-7.9. ATPase activity was measured photometrically by enzymatic coupling of the regeneration of ATP to the oxidat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(94)80727-1
更新日期:1994-12-01 00:00:00
abstract::We have formulated a kinetic model for the primary steps that occur at the cell membrane during receptor-mediated endocytosis. This model includes the diffusion of receptor molecules, the binding of receptors to coated pits, the loss of coated pits by invagination, and random reinsertion of receptors and coated pits. ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83879-0
更新日期:1985-01-01 00:00:00
abstract::The single photon response in vertebrate phototransduction is highly reproducible despite a number of random components of the activation cascade, including the random activation site, the random walk of an activated receptor, and its quenching in a random number of steps. Here we use a previously generated and tested...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.114058
更新日期:2008-05-01 00:00:00
abstract::The current article describes a new two-dimensional lambda-dynamics method to include proton tautomerism in continuous constant pH molecular dynamics (CPHMD) simulations. The two-dimensional lambda-dynamics framework is used to devise a tautomeric state titration model for the CPHMD simulations involving carboxyl and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.061341
更新日期:2005-07-01 00:00:00
abstract::Tendons are important load-bearing structures, which are frequently injured in both sports and work. Type I collagen fibrils are the primary components of tendons and carry most of the mechanical loads experienced by the tissue, however, knowledge of how load is transmitted between and within fibrils is limited. The p...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.04.033
更新日期:2013-06-04 00:00:00
abstract::The equation of motion for sperm flagella, in which the elastic bending moment and the active contractile moment are balanced by the moment from the viscous resistance of the surrounding fluid, is solved for a wave solution that superimposes partial solutions. Substitution of the expression for the wave solution into ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(78)85442-3
更新日期:1978-08-01 00:00:00