Using transmission electron microscopy, we investigate the thermally activated motion of domain walls (DWs) between two positions in Permalloy (Ni80Fe20) nanowires at room temperature. We show that ...this purely thermal motion is well described by an Arrhenius law, allowing for a description of the DW as a quasiparticle in a one-dimensional potential landscape. By injecting small currents, the potential is modified, allowing for the determination of the nonadiabatic spin torque: βt=0.010±0.004 for a transverse DW and βv=0.073±0.026 for a vortex DW. The larger value is attributed to the higher magnetization gradients present.
To induce an immunogenic response in vivo, an antigen-presenting (stimulator) cell must present both antigen-specific (class II MHC) and an accessory signal to the CD4 T cell. Failure to express the ...accessory signal has been shown in vitro to induce a state of specific unresponsiveness (anergy) in the T cell. We have shown that although stimulator cells in blood continue to express class II MHC molecules during refrigerated storage, their ability to present the accessory signal diminishes, reaching zero in all units tested by about 13 days. This implies that blood in excess of 2 weeks old should not alloimmunize but could induce some degree of immunosuppression. UV-B irradiation and, to a lesser extent, gamma-irradiation, were also shown to inhibit expression of the accessory signal by stimulator cells in blood.
Differences in cytokine patterns in stable chronic obstructive pulmonary disease (COPD), exacerbated COPD, smokers without apparent COPD, and healthy volunteers should be of interest for ...pathophysiological and therapeutic reasons. Methods including lavage, biopsy and sputum have been employed to investigate cytokines in the lung. For asystematic comparison, exhaled breath condensate (EBC) appears to be well suited.
We investigated healthy volunteers, smokers without apparent COPD, stable and exacerbated COPD patients (± inhalative steroids) and finally those whose exacerbation made mechanical ventilation inevitable, for a more complete picture of inflammatory cytokines in COPD. We chose EBC because it is non-invasive and can be used repeatedly in spontaneous breathing individuals and during mechanical ventilation. EBC cytokines (IL-1
β
, IL-6, IL-8, IL-10, IL-12p70, TNF-
α
) were assayed from a single sample using a multiplex array test kit.
We observed a significant increase of all cytokines in acute exacerbation compared to stable COPD, smokers, and volunteers. Stable COPD and volunteers exhibited only small differences in cytokine pattern with respect to IL-1
β
and IL-12
(
P
<
0.01
)
. Smokers had increased levels of all investigated cytokines
(
P
<
0.01
)
compared to non-smokers and, with the exception of IL-1
β
, to stable COPD. Inhaled steroids resulted in reduced levels of IL-1
β
, IL-6, IL-8, IL-10, and IL-12 (all:
P
<
0.01
) in stable COPD (all: ex-smokers) with dose dependency for IL-8, IL-1
β
and IL-12.
EBC analysis successfully characterized important differences in stable COPD compared to exacerbation or smoking and non-smoking healthy individuals.
Die Untersuchung des nicht invasiv zu gewinnenden Atemkondensates (EBC) spielt eine zunehmend größere Bedeutung im Rahmen des Monitoring akut inflammatorischer Erkrankungen. Neben der Bestimmung von ...pH-Wert und Leukotrienen kommt der Analyse von proinflammatorischen Interleukinen eine große Bedeutung zu. Hauptproblem bei der Analyse von Interleukinen im EBC war bisher der große Materialbedarf, der die gleichzeitige Bestimmung mehrerer Marker verhinderte.
Sechs verschiedene Interleukine wurden gleichzeitig und in derselben Probe aus dem lyophilisierten und rekonstituierten EBC (IL-12p70, TNF alpha, IL-10, IL-6, IL-1 beta, IL-8) mittels eines „cytometric bead array“ (CBA) auf einem FACS Calibur (Becton-Dickinson) bestimmt. Das EBC stammte von 10 gesunden Rauchern, 25 stabilen COPD Patienten, 18 Patienten mit akuter Infektexazerbation und 11 beatmeten Patienten mit einer schweren Pneumonie und Sepsis.
Signifikante Unterschiede zeigten sich zwischen den Gruppen mit akuter inflammatorischer Reaktion und den Patienten mit stabiler Erkrankung für alle untersuchten Interleukine (IL-12p70: p=0,002; TNF-alpha: p=0,001; IL-10: p=0,0001; IL-6: p=0,0001; IL-1 beta: 0,011; IL-8: p=0,001).
Diese Ergebnisse zeigen die Eignung eines partikelbasierten Immunoassays in der Analyse multipler Interleukine aus dem EBC. Pneumonie und Sepsis fielen durch erhöhte IL-8 und TNF alpha Werte auf, während IL-1 beta und IL-6 bei infektexazerbierten COPD Patienten besonders erhöht gefunden wurden.
Alkyl-lysophospholipids (ALPs) are reported to have an antineoplastic activity against leukaemic cells. We have tested some halogen-containing ALPs from the Central Institute of Molecular Biology (H. ...Brachwitz) in comparison with racemic 1-ostadecyl-2-methyl-glycero-3-phosphocholine (ET-18-OCH3) (P.G. Munder, Max-Planck-Institut für Immunobiologie, Freiburg, FRG). We found freshly dissolved ALPs to be very toxic both to human bone marrow and to leukaemic cells of patients. ALP-incubation before cryopreservation is more toxic to bone marrow (but not to AML blasts) than after cryopreservation. All experiments to test the selectivity and to establish a purging protocol should be done using 1, remission marrow including a cryopreservation step and 2, blasts of de novo leukaemias instead of cell as sensitive as HL 60 to ALP-incubation. We found direct toxicity of ALPs to be not suitable for purging lines of bone marrow from patients in remission.
Using transmission electron microscopy, we investigate the thermally activated motion of domain walls (DWs) between two positions in permalloy (Ni80Fe20) nanowires at room temperature. We show that ...this purely thermal motion is well described by an Arrhenius law, allowing for a description of the DW as a quasi-particle in a 1D potential landscape. By injecting small currents, the potential is modified, allowing for the determination of the non-adiabatic spin torque: the non-adiabatic coefficient is 0.010 +/- 0.004 for a transverse DW and 0.073 +/- 0.026 for a vortex DW. The larger value is attributed to the higher magnetization gradients present.
Experiments with Coombs-sera as raw and usable sera having different levels of titre were carried out in order to examine their stability in fluid nitrogen. Therewith, significant differences ...concerning the storing stability did not appear. Generally seen two third of the sera retained their initial titres at the end of one year in store.
In a survey different methods of culture are represented for the purpose of identifying and quantifying haemopoietic stem cells (CFU-GEMM, CFU-GM, CFU-E/BFU-E) in human bone-marrow or peripheral ...blood respectively. On the basis of findings from international medical literature their validity is explained in the diagnostics and prognosis of some haematological diseases, such as acute and chronic myeloic leukemia, aplastic anemia, preleukemia. Special attention is given to their significance within bone-marrow transplantation. Their importance in evaluating transplantations after their preceding in-vitro manipulation as to the separation of rest tumour and T-cells is particularly referred to.
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