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71.
Jacques R. Caldwell David E. Pearce Craig Spencer Rosmarie Leder Robert H. Waldman 《The Journal of allergy and clinical immunology》1973,52(4):225-230
Immunologic studies were performed on 5 patients with pigeon breeders' disease. Intradermal injection of pigeon serum produced an immediate wheal-and-flare reaction within 15 minutes and a secondary Arthus-type reaction within 4 to 8 hours. Immunofluorescent studies of the secondary reaction site showed IgG, C3, and C4 in 2 patients. Patients' sera produced multiple precipitin bands with pigeon serum when reacted by double diffusion in gel. IgG antibody isolated from each of the patients' serum formed precipitating immune complexes that fixed large amounts of complement (C4) when added to fresh human serum. Peripheral blood lymphocytes from 4 of the 5 patients produced macrophage migration inhibitory factor (MIF) when challenged with dilute pigeon serum. These studies are the first to show complement fixing antibodies and macrophage MIF production by lymphocytes from patients with hypersensitivity lung disease and suggest that both humoral and cellular immunity may be important in the pathogenesis of these disorders. 相似文献
72.
Patrice Hermann Dominique Blanchard Blandine de Saint-Vis Franois Fossiez Claude Gaillard BAtrice Vanbervliet Francine Brire Jacques Banchereau Jean-Pierre Galizzi 《European journal of immunology》1993,23(4):961-964
To identify the ligand(s) of the human CD40 antigen, a cDNA encoding the extracellular domain of the CD40 antigen was fused to a cDNA encoding the constant region (Fc) of human IgGl. The CD40-Fc fusion protein was able to specifically bind to CD4+ and various CD8+ T cell clones activated with immobilized anti-CD3. The 125I-labeled CD40-Fc fusion protein bound anti-CD3 activated CD4+ T cell clone (MT9) with an equilibrium dissociation constant (Ka) of 10-20 nM. The human CD40-binding protein expressed on the cell surface of activated T lymphocytes is a monomeric protein of ≈ 32 kDa. Minor components of 29 kDa and 17 kDa were also detected. A small proportion of CD4+ and CD8+ blood mononuclear T cells activated by anti-CD3 expressed the CD40 ligand but its detection was best observed following depletion of B cells. Addition of B cells to purified T cells abolished the binding of CD40-Fc obtained after anti-CD3 activation. 相似文献
73.
David Cohen Jacques Michel Mina Ferne Sonya Bergner-Rabinowitz Isaac Ginsburg 《Inflammation》1979,3(4):395-403
Leukocyte extracts, trypsin, and lysozyme are all capable of releasing the bulk of the LPS from S. typhi, S. typhimurium, and E. coli. Bacteria which have been killed by heat, ultraviolet irradiation, or by a variety of metabolic inhibitors and antibiotics which affect protein, DNA, RNA, and cell wall synthesis no longer yield soluble LPS following treatment with the releasing agents. On the other hand, bacteria which are resistant to certain of the antibiotics yield nearly the full amount of soluble LPS following treatment, suggesting that certain heatlabile endogenous metabolic pathways collaborate with the releasing agents in the release of LPS from the bacteria. It is suggested that some of the beneficial effects of antibiotics on infections with gram-negative bacteria may be the prevention of massive release of endotoxin by leukocyte enzymes in inflammatory sites. 相似文献
74.
Paulette Mezin Jean-Paul Brion Jacques Vermont Max Micoud Pierre Stoebner 《Ultrastructural pathology》1991,15(6):593-602
Light and electron microscopic studies were performed on neuromuscular biopsy specimens from 12 neurologically affected seropositive patients, 7 with the acquired immune deficiency syndrome (AIDS), 2 with AIDS-related complex, and 3 with no symptoms except for neuropathy. All patients had an axonal injury associated or unassociated with demyelination and peripheral neurogenic atrophy. Capillary lesions were consistently present, which seems to be a new finding. Moreover, tubuloreticular inclusions (TRIs) were found in endomysial (9 of 12 cases) and endoneurial (7 of 12 cases) vessels. Statistical analysis showed that TRIs in more than 20% of endomysial vessels correlated with a survival time shorter than 12 months (P = 0.028). Thus the quantification of TRIs seems to be one of the vital prognostic elements in this patient population. 相似文献
75.
76.
Muriel Moser Thibaut De Smedt Thierry Sornasse Franoise Tielemans Aziz Alami Chentoufi Eric Muraille Marcelle Van Mechelen Jacques Urbain Oberdan Leo 《European journal of immunology》1995,25(10):2818-2824
Exogenous glucocorticoid hormones are widely used as therapeutical agents, whereas endogenous glucocorticoids may act as physiological immunosuppressants involved in the control of immune and inflammatory responses. The optimal activation of T lymphocytes requires two distinct signals: the major histocompatibility complex-restricted presentation of the antigen and an additional co-stimulatory signal provided by the antigen-presenting cells. There is ample evidence that, among the cells able to present the antigen, the dendritic cells (DC) have the unique property to activate antigen-specific, naive T cells in vitro and in vivo, and are therefore required for the induction of primary immune responses. In this work, we tested whether glucocorticoids affected the capacity of DC to sensitize naive T cells. Our data show that, in vitro, the steroid hormone analog dexamethasone (Dex) affects the viability of DC, selectively downregulates the expression of co-stimulatory molecules on viable DC, and strongly reduces their immunostimulatory properties. In vivo, a single injection of Dex results in impaired antigen presenting function, a finding which correlates with reduced numbers of splenic DC. These results show that glucocorticoids regulate DC maturation and immune function in vitro and in vivo and suggest that this mechanism may play a role in preventing overstimulation of the immune system. 相似文献
77.
Jacques Chappuis Igor A. Sherman A. Wilhelm Neumann 《Annals of biomedical engineering》1983,11(5):435-449
Measurements of the surface tension of articular cartilage and friction experiments were carried out to provide further evidence
in support of a new theory regarding the mechanism of friction in joints. To determine the surface tension of cartilage, contact
angle measurements were used in conjunction with the equation of state for interfacial tensions. The advancing contact angle
between saline drops and articular cartilage was found to be 100°±5°, indicating a highly hydrophobic surface. The corresponding
surface tension value was calculated to be 22.5 ergs/cm2. Friction of cartilage against hydrophobic surfaces is shown to be lower than the friction of cartilage against hydrophilic
surfaces. All these results further support the theory that lubrication by nonwetting drops occurs in joints and may be responsible
for the exceptional friction characteristics of the joints. 相似文献
78.
Bernard Roussel Jacques Bittel 《Pflügers Archiv : European journal of physiology》1979,382(3):225-231
Thermogenesis (VO2), sensible heat loss and subcutaneous back temperature were recorded simultaneously during sleeping and waking in both intact and depilated rats at Ta ranging from 21–28°C.VO2 increased during wakefulness (W), decreased and plateaued during slow wave sleep (SWS) and then decreased 10% with each paradoxical sleep (PS) phase. Sensible heat loss, which represented about 90% of the heat production, increased and plateaued during SWS, decreased in W and generally rose abruptly (+40%) during PS. After removal of the fur the mean levels ofVO2 and sensible heat loss were increased by 30–50% and returned to normal values within two weeks, although their variations related to stages of sleep were unchanged.These results concerning thermogenesis and thermolysis are in agreement with the variations of body temperature (brain excluded) during sleeping and waking. 相似文献
79.
J. Jacques 《International journal of experimental pathology》1969,50(5):486-489
Lathyrism, which affects developing connective tissue, is produced by extracts of sweet-pea seeds (Lathyrus odoratus) and by various amino-nitriles. The basic lesion is a defect in the intra- and inter-molecular bonding of collagen, as a result of which wound tensile strength is diminished. Wounds involving skin loss in rats heal largely by a process known as contraction, in which the skin edges are brought together, leaving only a small defect to be closed by the migrating epithelium. Here, it has been found that a lathyrogenic agent (β-aminopropionitrile) has no effect on wound contraction and the implications of this are discussed. The result suggests that tensile strength and contraction reflect different aspects of healing. 相似文献
80.
Akeb F Ferrua B Creminon C Roptin C Grassi J Nevers MC Guedj R Garraffo R Duval D 《Journal of immunological methods》2002,263(1-2):1-9
The HIV protease inhibitor ritonavir (Norvir; ABT-578), currently used in combination with nucleoside analogs and other protease inhibitors in anti-HIV therapy, has previously been quantified by an HPLC procedure. Here, we report the first convenient one-step competitive ELISA for measuring plasma and intracellular ritonavir in HIV patients. Anti-ritonavir antibody was raised in rabbits using ritonavir-KLH conjugate as immunogen, and the enzymatic tracer was prepared by coupling the drug to acetylcholine esterase. Samples for analysis were first extracted with methanol. Bound/free separation was achieved in a microtiter plate previously coated with anti rabbit IgG monoclonal antibody. Fifty percent inhibition was observed at 1 ng/ml ritonavir and the method accurately and specifically detected as little as 3-4 ng/ml of plasma ritonavir as well as intracellular drug in the peripheral blood mononuclear cells of patients undergoing ritonavir therapy. Within-run and day to day coefficients of variation were below 10% and the drugs currently used in HIV therapy did not interfere with the test. The ELISA was applied to the measurement of plasma ritonavir and to the determination of the extracellular/intracellular drug level ratios in HIV patients receiving long-term multidrug therapy. 相似文献