We show through nonequilibrium nonadiabatic electron-spin-lattice simulations that above a critical current in magnetic atomic wires with a narrow domain wall (DW), a couple of atomic spaces in width, the electron flow triggers violent stimulated emission of phonons and magnons with an almost complete conversion of the incident electron momentum flux into a phonon and magnon flux. Just below the critical levels of the current flow, the DW achieves maximal velocity of about 3×10^{4} m/s, entering a strongly nonadiabatic regime of DW propagation, followed by a breakdown at higher biases. Above this threshold, a further increase of the current with the applied bias is impossible-the electronic current suffers a heavy suppression and the DW stops.
View Article and Find Full Text PDFUsing the sensitivity of optical second harmonic generation to currents, we demonstrate the generation of 250-fs long spin current pulses in Fe/Au/Fe/MgO(001) spin valves. The temporal profile of these pulses indicates ballistic transport of hot electrons across a sub-100 nm Au layer. The pulse duration is primarily determined by the thermalization time of laser-excited hot carriers in Fe.
View Article and Find Full Text PDFIn a straightforward application of molecular nanospintronics to quantum computing, single-molecule spin transistors can be used to measure nuclear spin qubits. Conductance jumps accompany electronic spin flips at the so-called anticrossings between energy levels, which take place only at specific magnetic fields determined by the nuclear spin state. To date, the only molecular hardware employed for this technique has been the terbium(III) bis(phthalocyaninato) complex.
View Article and Find Full Text PDFWe present a time-dependent study of electron transport through a strongly correlated quantum dot, which combines adiabatic lattice density functional theory in the Bethe ansatz local-density approximation (BALDA) to the Hubbard model, with the multiple-probe battery method for open-boundary simulations in the time domain. In agreement with the recently proposed dynamical picture of Coulomb blockade, a characteristic driven regime, defined by regular current oscillations, is demonstrated for a certain range of bias voltages. We further investigate the effects of systematically improving the approximation for the electron-electron interaction at the dot site (going from non-interacting, through Hartree-only to adiabatic BALDA) on the transmission spectrum and the I-V characteristics.
View Article and Find Full Text PDFInt J Chron Obstruct Pulmon Dis
January 2013
Background: αB-crystallin (HspB5) is a chaperone whose role as a marker of innate immunity activation as well as its therapeutic potential have recently been investigated in several inflammatory diseases: multiple sclerosis, myocardial ischemia, and Guillain-Barré syndrome.
Aim: The aim of this study is to determine the role of αB-crystallin in chronic obstructive pulmonary disease (COPD) pathogenesis and inflammation.
Materials: Plasma levels of αB-crystallin were studied in 163 patients: 52 healthy non-COPD smokers; 20 COPD smokers in Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages I-II; 43 COPD smokers in GOLD stages III-IV.
Objective: Alpha-B-crystallin, a small heat-shock protein, recently gained major interest because of its differential expression during tumourigenesis and metastasis in various epithelial tumours. The purpose of this study was to investigate the expression of alpha-B-crystallin and its biologic and prognostic significance in non-small-cell lung cancer (NSCLC).
Methods: Immunohistochemical analysis was performed on a tissue microarray slide containing samples from 146 NSCLC patients who were operated on between 2004 and 2005.
Am J Reprod Immunol
November 2008
Problem: Expression of heat shock proteins has been described in different tissues relevant to human reproduction, including placenta. AlphaB-crystallin is a member of the small heat shock protein family (sHsp) exerting biologically important chaperon functions.
Method Of Study: Immunofluorescence; immunoblot analysis; quantitative real-time-PCR; CpG island methylation analysis.
Objective: To determine whether first-trimester human decidua contains multipotent stromal cells capable of differentiating into other cell lines.
Design: In vitro-cultured decidual stromal cells were analyzed by flow cytometry and induced to differentiate into osteogenic and adipogenic lineages, endothelial cells, and PRL-secreting mature decidual cells.
Setting: Research laboratory.
Human endometrium is an object of extensive restructuring and remodeling during the female reproductive life and it is quite tempting to assume that these periodic changes happen with the participation of cells that should have the basic characteristics of multipotent cells. The aim of this study was to search for the presence of cells with plastic adherence, clonogenicity, and differentiation in human endometrium. To this end, human endometrial stromal cells were cultured in vitro for more than 15 passages.
View Article and Find Full Text PDFAkush Ginekol (Sofiia)
November 2007
The endometriosis is gynecological disease what is characterized with the presence of endometrial lesions are composed of endometrial epithelial and stromal cells outside of the uterus. There are many theories for the development of the disease endometriosis. The most widely accepted theory is the theory what is postulated the endometriosis is a result of retrograde menstruation.
View Article and Find Full Text PDFA dynamical method for simulating steady-state conduction in atomic and molecular wires is presented which is both computationally and conceptually simple. The method is tested by calculating the current-voltage spectrum of a simple diatomic molecular junction, for which the static Landauer approach produces multiple steady-state solutions. The dynamical method quantitatively reproduces the static results and provides information on the stability of the different solutions.
View Article and Find Full Text PDFInvestigations on specific and functionally active sperm antigens would bring about the elucidation of the mechanisms of gamete interaction and help the search to new approaches for prognosis and regulation of fertility. Previously, we have produced a polyclonal rabbit anti-boar spermatozoa antibody (RABSA) that might affect the fertilizing capacity of boar spermatozoa. The sperm specificity of RABSA was demonstrated by double immunodiffusion, immunoelectrophoresis and ELISA against boar spermatozoa, as well as against saline extracts of boar reproductive and somatic organs.
View Article and Find Full Text PDFIn this study, the authors tried to figure out the value of immunodiagnostics, and especially the protein characteristics of the peritoneal fluid in women with endometriosis. The main purpose was to establish whether this kind of diagnostics is reliable enough for clinical purposes.
View Article and Find Full Text PDFBackground: The usual sources of antigenic material for investigations on circulating immunoglobulins with anti-lens crystallins specificity are saline extracts of human cataract lenses. This practice has a number of drawbacks, especially the possible antigenic alterations that may have occurred in cataract lenses. The aim of this investigation was to compare the antigenic properties of porcine eye lens crystallins and human crystallins, with regard to the possibility for an alternative source of antigenic material for detection of anti-crystallin antibodies in human sera.
View Article and Find Full Text PDFAm J Reprod Immunol
October 1999
Problem: Monoclonal anti-capacitated sperm antibody has been used as a probe to identify, isolate, and characterize specific, fertilization-related antigen with some characteristic features that point to its possible significance in immunocontraception.
Method Of Study: Fast protein liquid chromatography (FPLC), enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and isoelectrofocusing were used for isolation, immunochemical and physicochemical characterization of a monoclonal antibody (mAb) 1F10 cognate antigen. Sperm-zona pellucida binding and hemizona assay were used for testing the biological roles of mAb 1F10 and Ag 1F10 in boar and human fertilization processes.
Investigations on the specific idiotypes of autoantibodies are supposed to help with the understanding of the control mechanisms participating in the pathogenesis of autoimmune diseases. This study describes three monoclonal antibodies (Mabs) that recognize distinct idiotypic determinants on anti-insulin autoantibodies. The preabsorption by IAA-positive sera of insulin inhibits their subsequent binding to the anti-Id, thus suggesting that the Mabs recognize epitopes located at or near the binding site of insulin autoantibodies (IAA).
View Article and Find Full Text PDFTo compare the crystallin composition of embryonic and fetal human lenses with those of postnatal and adult lenses, we investigated the crystallins of lenses of various ages (from the 5th gestational week to 55 years) by gel chromatography, isoelectric focusing, immunodiffusion, and immunoelectrophoresis. Age-related changes were calculated as relative percentages of the different classes and subclasses of crystallins. During prenatal lens development the percentages of both high- and low-molecular-weight alpha-crystallins as well as gamma-crystallins gradually increased, whereas the percentage of beta-crystallins decreased.
View Article and Find Full Text PDFInt J Biochem Cell Biol
November 1995
Monoclonal antibody designated 1B10 (Mab 1B10) has been shown to be highly specific for the beta-chain of human chorionic gonadotrophin (HCG). We used this antibody to investigate its paratope using anti-idiotypic antibodies. Purified Mab 1B10 has been used to immunize syngeneic BALB/c mice to produce anti-idiotypic monoclonal antibodies.
View Article and Find Full Text PDFAn anti-digoxin monoclonal antibody (mAb 4G3) has been produced and characterized with respect to its fine specificity and affinity. In an independent series of experiments anti-idiotypic monoclonal antibody (mAb 7G9) was selected which reacted with the antigen-binding center of an anti-human chorionic gonadotropin monoclonal antibody (anti-hCG mAb 1B10). In detailed studies on its binding characteristics it has been shown that mAb 4G3 binds to an anti-idiotypic monoclonal antibody mAb 7G9 in solution.
View Article and Find Full Text PDFSaline extracts from human lenses were studied during prenatal eye development. Using immunodiffusion and immunoelectrophoresis with a specific antiserum against total extract of human adult lenses and monospecific antisera against the individual crystallin classes, it was established that alpha and beta crystallins were present in extracts from eye lenses from 5-week-old embryos while gamma crystallins could be detected in extracts from embryonic lenses at the beginning of the 6th gestational week. When analyzed by isoelectric focussing all alpha and beta crystallin components were found in extracts from 8-week-old embryos, while those of gamma crystallins were shown to appear successively within the period between the 8th and 14th gestational week.
View Article and Find Full Text PDFOur previous investigations have demonstrated that saline extract of Arum maculatum contains lectin (sperm agglutinin) which agglutinates human ejaculated spermatozoa of the type tail to tail and head to tail. By means of speed liquid chromatography (Mono S XP 5/5) eight fractions (I-VIII) were obtained. The sperm-agglutinating activity of the fractions was investigated against frog testicular spermatozoa and testicular and epididymal spermatozoa of man, rabbit, rat and mouse.
View Article and Find Full Text PDFThe delipidized saline extract of Arum maculatum (AM) contains two selectively agglutinating human spermatozoa isolectinesphytospermoagglutinins (FSA1 and FSA2), which bind to various receptors of spermatozoon plasmalemma. It is established by means of disc polyacrilamide electrophoresis amino acid analysis and isoelectric focusing that FSA1 is tetrameter, but FSA2-octameter, which have similar amino-acid content and do not contain carbohydrates. The established structural differences probably cause also the capability of FSA1 and FSA2 to bind various receptors of spermatozoon plasmalemma.
View Article and Find Full Text PDFFolia Biol (Praha)
August 1990
Spleen cells from mice immunized with human chorionic gonadotropin (hCG) were fused with mouse myeloma cells and four hybridomas, secreting monoclonal antibodies, were selected for further studies. In cross-check tests against tissue extracts and peptide hormones it was established that mAb IB10 (IgG1) reacted positively against hCG only but not with other hormones. Ascites from this hybridoma was fractionated by ammonium sulphate precipitation and by FPLC to isolate the IgG fraction.
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