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1.
Summary A small population of T cells does not express the conventional T cell receptor characterized by the and polypeptide chains (TCR) but instead, two polypeptides termed and (TCR). This alternative receptor is able to recognize antigen. It appears early in T cell ontogeny, but its role in the thymus prior to the availability of TCR remains unclear. In selected sites such as skin or gut TCR predominates in mice which might suggest a role of T cells in the first line of defense against infection, T cells secrete lymphokines and display cytotoxic activity. However, their activation requirements may differ from what is known for T cells since MHC-nonrestricted and also CD4 and CD8 negative T cells have been described. Preferential activation by mycobacterial antigens possibly indicates a special repertoire of the T cells. In various diseases slightly increased numbers of T cells were found, but these preliminary studies have not yet provided evidence for a major pathogenetic role of T cells.List of abbreviations C constant region (immunoglobulin or TCR gene segment) - CD4 cluster of differentiation 4 (mainly on helper cells) - CD8 cluster of differentiation 8 (mainly on cytotoxic cells) - D diversity region (immunoglobulin or TCR gene segment) - DNA desoxyribonucleic acid - IL2 interleukin 2 - J joining region (immunoglobulin or TCR gene segment) - kD kiloDalton - MHC major histocompatibility complex - NK natural killer (cells) - RA rheumatoid arthritis - TCR T cell receptor - V variable region (immunoglobulin or TCR gene segment)  相似文献   

2.
We studied the effects of 1-acid glycoprotein on tumor necrosis factor- (TNF-) and interleukin-10 (IL-10) production and lymphocyte response to phytohemagglutinin in cultured peripheral blood mononuclear leukocytes from 6 healthy donors. We observed 2 opposite responses to 1-acid glycoprotein: first, stimulation of TNF- and IL-10 production and inhibition of lymphocyte proliferation, and second, suppression of cytokine production and stimulation of lymphocyte proliferation. In cell cultures isolated from 4 of 6 donors, the TNF-/IL-10 ratio remained unchanged after addition of native 1-acid glycoprotein, but some fractions isolated by chromatography on concanavalin A-Sepharose changed this parameter. These changes were most pronounced after treatment with fraction C enriched with molecules with incomplete (biantennary) carbohydrate chains. The mechanisms of 1-acid glycoprotein-induced effects on peripheral blood mononuclear leukocytes are discussed.  相似文献   

3.
Summary Studies have been made of the heterogeneity of infectivity and CFA in Teschen virus (Talfan strain) suspensions. Most of the infectivity was contained in two components of densities 1.46 gm./ml. and 1.35 gm./ml. The physical, chemical and immunological properties of these components have been compared. It was possible, however, to convert a large proportion of 1.46 component to 1.35 component by treating the 1.46 component with sodium dodecyl sulphate. This would indicate that the 1.46 component was a complex formed between the infective particles and cellular debris.Further studies on the growth characteristics and electron microscopy of the virus have been made.  相似文献   

4.
The human protease inhibitor genes 1 antitrypsin (1-PI) and 1-antichymotrypsin (1-ACT) are acute-phase proteins which are induced in response to inflammation. These inhibitors function to limit the activity of serine proteases in vivo. 1-PI acts as an inhibitor of neutrophil elastase to protect the elastin fibers of the lung. Genetic deficiencies of 1-PI result in development of chronic pulmonary emphysema. The physiologic role of 1-ACT has not been clearly defined, but it also appears to function in the maintenance of protease-protease inhibitor equilibrium in the lung. Nucleic acid and protein sequence homologies detected between 1-PI and 1 t-ACT suggested an evolutionary relationship. Gene mapping experiments were performed to determine if these protease inhibitor genes reside at the same chromosomal locus in man. In situ hybridization data demonstrate that both 1-PI and 1-ACT map to the same region, q31–q32.3, on chromosome 14.  相似文献   

5.
Summary A caldesmon kinase activity was partially purified from an extract of chicken gizzard smooth muscle by sequential chromatography on columns of DEAE-Sephacel, MonoQ and Superose 12. This kinase was identified as casein kinase II by Western blotting using peptide-directed antibodies raised against the , and subunits of human casein kinase II; the smooth muscle enzyme consisted of similar subunits of Mr 43 000 (), 39 000 (), and 27 000 (). Phosphorylation of caldesmon and casein by smooth muscle casein kinase II was optimal at 0.1 M NaCl, did not require second messengers, and was inhibited by heparin. The kinase utilized either GTP or ATP as a substrate. Caldesmon was phosphorylated to 1 mol Pi mol-1 caldesmon by smooth muscle casein kinase II with a Km for caldesmon of 4.9 M. Two-dimensional thin-layer electrophoresis indicated phosphate incorporation into both serine and threonine. All the incorporated phosphate was recovered in the N-terminal peptide (residues 1–152) generated by cleavage at cysteine 153 with 2-nitro-5-thiocyanobenzoic acid. Purification of tryptic phosphopeptides and N-terminal sequencing revealed two principal sites of phosphorylation: serine 73 and threonine 83. The following four synthetic peptides corresponding to this domain of caldesmon were examined as substrates of casein kinase II: A = RRREVNAQNSVAEEE; B = AQNSVAEEE; C = RSTDDEAA; D = SVAEEETKRSTDDE. Interestingly, only peptides C and D were phosphorylated and both only at threonine. Phosphorylation of intact caldesmon did not affect the pattern of chymotryptic digestion suggesting that it does not induce a significant conformational change in the protein substrate. Phosphorylation also had no effect on the binding of caldesmon to actin or on the caldesmon-mediated inhibition of actomyosin MgATPase activity. However, phosphorylation completely abolished the interaction of caldesmon with immobilized smooth muscle myosin. These results are consistent with the localization of the myosin-binding domain near the N-terminus of caldesmon and of the actin-binding domain near the opposite end of the elongated molecule. Casein kinase II may therefore play a role in regulating caldesmon-myosin interaction and the ability of caldesmon to cross-link actin and myosin filaments in smooth muscle.  相似文献   

6.
Zusammenfassung Seit Juli 1978 wurden 103 Patienten mit inoperablem kleinzelligem Bronchialkarzinom mit der Zytostatikakombination Adriamycin, Cyclophosphamid und Vincristin (ACO) behandelt. Im Stadium limited disease (n=64) erfolgte während des zweiten Chemotherapiekurses eine prophylaktische Schädelbestrahlung, nach dem vierten eine konsolidierende thorakale Bestrahlung. Nach Erreichen einer kompletten Remission erhielten die Patienten prospektiv randomisiert Etoposid oder keine weitere spezifische Therapie. Ein objektives Ansprechen konnte bei 88/100 auswertbaren Patienten erzielt werden. Im Stadium limited disease fanden sich 72%, im Stadium extensive disease nur 33% komplette Remissionen. Im Stadium limited disease betrug die hochgerechnete mediane Überlebenszeit 15,8, im Stadium extensive disease 9,3 Monate (p<0.005). Es leben noch 29 Patienten, 4 rezidivfrei länger als 24 Monate. Patienten mit kompletter Remission hatten eine statistisch signifikant (p<0.001) längere Überlebenszeit als Patienten mit geringerem Ansprechen. Regelmäßig traten gastrointestinale und hämatologische Nebenwirkungen auf, drei Patienten starben während der Induktionsphase an Infektionen. Die kurzzeitige Induktionsbehandlung verbesserte jedoch den Krankheitsverlauf subjektiv und objektiv. Bisher ist kein positiver Effekt der zyklischen Etoposid-Gabe nach ACO festzustellen.Vorliegende Untersuchungen wurden gefördert im Rahmen des Forschungsprogramms Arzneimittelentwicklung und -testung für die Krebstherapie des BMFT  相似文献   

7.
Effects of G protein subunits from rat brain on cardiac K+ channel was examined in single atrial cells of guinea-pig, using patch clamp techniques. We found that 10 pM concentration of rat brain subunits preparation could activate the atrial muscarine receptor-gated K+ channel (IK.ACh). Neither the detergent, CHAPS, used to suspend nor the boiled preparation activated IK.ACh. Furthermore, preincubation of subunits preparation in Mg2+-free solution, which easily inactivated -GTP-S, did not affect -activation of IK.ACh. We concluded, therefore, that subunits themselves can activate IK.ACh.Supported by the grants from the Ministry of Education, Culture and Science of Japan and from the Calcium Signal Workshop on Cardiovascular Systems  相似文献   

8.
The roles of endotoxin (LPS) and tumor necrosis factor- (TNF-) in the causation of organ injury during sepsis are unclear. To study LPS and TNF- in the genesis of lung inflammation after cecal ligation and puncture (CLP), we used endotoxin-resistant (C3H/HeJ) and endotoxin-sensitive mice (C3H/HeOuJ). We examined lung neutrophil sequestration, interleukin 1 (IL-1) mRNA expression, IL-1 protein expression, and injury. We also determined the expression of two C-X-C chemokine mRNAs, macrophage inflammatory protein-2 (MIP-2) and KC, in the lung to determine whether in vivo, endotoxin, or TNF- are significant modulators of MIP-2 and KC mRNA expression. After CLP, increased neutrophils sequestrated in the lungs of both strains of mice and coincided with an increase in expression of IL-1, MIP-2 and KC mRNAs, and IL-1 protein. Lung and serum TNF- were significantly increased in the C3H/HeOuJ strain but not in the C3H/HeJ strain. Histologic studies of the lung revealed similar injury in both strains. Our results suggest that bacterial factors other than endotoxin cause lung neutrophil sequestration and injury after CLP and further, that TNF- production is not a prerequisite. Our findings also suggest a potential role for local pulmonary chemokine production in the control of neutrophil sequestration after CLP.  相似文献   

9.
A strain ofKlebsiella pneumoniae K25 resistant to newer-lactam drugs was isolated in clusters in five hospitals in the Paris area. The MICs of ceftazidime and aztreonam (128 mg/l) were higher than that of cefotaxime (16 mg/l) for the strain but when measured in the presence of clavulanic acid, they were 1 mg/l. The donor strains and derivatives produced a-lactamase with a pI of 7.75–7.8 and hydrolysing activity against a wide spectrum of-lactams similar to that of SHV-2 and SHV-3, but with significant hydrolysis of ceftazidime. This new enzyme could be designated SHV-4.  相似文献   

10.
Zusammenfassung AnpassungsvorgÄnge bei informatorischen TÄtigkeiten in Me\grö\en der Leistung — Cycluszeiten, deren Streuung, deren informatorische Anteile und Fehler — und der physiologischen Beanspruchung — Elektromyogramme des m. extensor digitorum und m. rhomboideus, horizontales und vertikales Elektrooculogramm, Herzfrequenz und Arrhythmie — werden dargestellt und nach Art und HÄufigkeit beschrieben. Simultanrekationen und Sukzessivreaktionen aller Me\grö\en über die Schichtzeit — und drei aufeinanderfolgende Tage — werden beschrieben, nach den Ursachen übung und emotionale Gewöhnung zusammengefa\t und im Hinblick auf ein Modell Experimentator — Experimentalsituationen diskutiert.  相似文献   

11.
In the process of developing an intravenously injectable drug, its haemolytic potential must be considered. There are no Regulatory Guidelines for this kind of test. Many authors have set up different models, attempting to obtain early information about the behaviour of test compounds when injected into the bloodstream.In the present work, an in vitro static model is presented, which takes into account the injection rate (R inj.) of the drug, and the blood flow rate (Q v) of the vein in which the drug must be injected. From the relationship between these two parameters, the Cmax, expressed as mg/ml, can be calculated. This latter parameter allows us to calculate the drug concentration which, at any moment during injection, comes into contact with a known aliquot of new' blood passing through the injection site. Furthermore, a dynamic test has been developed, which simulates an injection into the blood flow using a tubing system and infusion pumps set for the same R ini. and Q v values used in static test. Two injectable drugs, Valium® and Lanoxin®, and a commonly used vehicle, propylene glycol, have been tested by both the methods. These compounds have also been tested with another in vitro method (Prieur et al. 1973), in which a volumetric blood-to-test solution ratio of 1:1 is adopted for every drug tested, with neither R inj. nor Q v being taken into account. Results of the haemolytic potential obtained with the three tests have been compared.A good correlation has been observed between the static and the dynamic tests, whereas Prieur's model, which uses a drug-to-blood ratio which is far higher than in vivo, has been shown to give false positive results.It is concluded that a test for the evaluation of the haemolytic potential of drugs must take into account the pharmacodynamic characteristics of the formulation intended to be injected, and at least the blood flow rate. The proposed static test has been demonstrated to be an easy and reliable method of obtaining a true picture of the in vivo situation.  相似文献   

12.
Zusammenfassung Bei Implantationen von Diäthylstilböstrol in einen ventralen Prostatalappen der Ratte konnte im Gegensatz zum Bayer E 39 keine direkte zellschädigende Wirkung auf das Prostatagewebe beobachtet werden. Ein antigonadotroper und damit antimaskuliner Effekt war dagegen neben einer Nebennierenrindenstimulierung sicher nachweisbar. Es wird daraus geschlossen, daß auch das wasserlösliche Diäthylstilböstroldiphosphat bei der Behandlung des Prostatacarcinoms nicht als Cytostaticum sondern als Östrogen wirkt.Eingeführt als St-52 von Asta, Brackwede; jetzt Honvan (Asta) bzw. Cytonal (VEB Beropharm, Berlin-Johannisthal).  相似文献   

13.
The aim of this study was to examine the distribution of 1 and v integrins (Ints) and some of their ligands in the kidneys of patients with congenital nephrotic syndrome of the Finnish type (CNF) and in controls using indirect immunofluorescence with monoclonal antibodies. The mesangial reactivity of Int 1 and Int 1 subunits was more variable and an increased glomerular reactivity with Int 3 and Int-6 antibodies was found in CNF kidneys than in controls. Int 2 subunit was either completely missing from or found in significantly lesser amounts in CNF kidney glomeruli. The immunoreactivity for Int v was more variable, fainter and also more granular in CNF samples than in control kidneys. The glomerular reactivity for Int 5 was more diffuse and weaker, and in sclerotic Bowman's capsules more intense in CNF kidneys than in controls. Immunoreactivity for Int 6 was restricted and was comparable in extent in CNF and control kidneys. Of the extracellular matrix components studied, the expression of EDAFn, EDBFn, OncFn, Ln 2 chain, Ln 1 chain and tenascin was increased. This is also seen in several glomerular diseases with inflammation and sclerosis. Immunoreactivity for vitronectin was decreased. Several differences were found in the intensity or location of the immunostaining for the 1 and v Ints and their ligands in CNF kidneys compared with controls, which have not been found in any other proteinuric disease. Disturbed Int expression pattern in CNF may specifically reflect the disturbance of glomerular function caused by the primary defect in this disease.  相似文献   

14.
The effects of interleukin-1 and were tested on the [3H]-arachidonic acid release and the prostaglandin synthesis by human cultured synovial cells and chondrocytes. Both forms of interleukin-1 stimulated the arachidonic acid release but interleukin-1 was more potent than IL-1. Human synovial cells and chondrocytes synthesized three types of prostaglandins upon stimulation with interleukin-1 or : prostaglandin E2, F2 and 6-keto-prostaglandin F1. Regarding the synthesis of these prostaglandins, IL-1 was again more potent than IL-1. A comparison between interleukin-1-stimulated synovial cells and chondrocytes revealed neither significant quantitative nor qualitative differences in both the arachidonic acid release and the prostaglandin synthesis.  相似文献   

15.
Zusammenfassung Auf Grund ihres immunbiologischen Verhaltens gehören die Leptospirenstämme Sari, Ghidorsi und Szwajizak zu demselben serologischen Leptospirentyp, für den der Name Leptospira Mini vorgeschlagen wird.Der Stamm Sari wurde 1942 vonMino sowieVercelli in Italien isoliert. Der Stamm Ghidorsi wurde von uns im Zuge unserer Leptospirenforschungen bei einer Reisfeldarbeiterin der Po-Ebene nachgewiesen. Der Stamm Szwajizak, der vonSmith, Brown, Tonge u. Mitarb. im Jahre 1954 beschrieben wurde, ist in Nord-Qeensland gefunden worden. Der Stamm Sari und Ghidorsi gehören dem kompletten Biotyp (AB), der Stamm Szwajizak dem inkompletten (A) an.Leptospira Mini gehört zur Serogruppe hebdomadis. Ihre Virulenz ist schwach und ihre Bedeutung als Erreger menschlicher Leptospiren-infektionen scheint gering zu sein.  相似文献   

16.
Nephritogenicity (anti-GBM-nephritis-inducing activity) and -chain composition of globular-domain (NC1) fractions of type IV collagen from bovine renal, pulmonary, and placental basement membranes (BMs) was examined by injecting these fractions with adjuvant into WKY/NCrj rats and by Western blotting using epitope-defined monoclonal antibodies to the six different chains of type IV collagen. A purified nephritogenic fraction from renal BM contained 1–6(IV)NC1, whereas a non-nephritogenic fraction contained only 1–2(IV)NC1. Renal and pulmonary NC1 had strong nephritogenic activity; placental NC1 had weak activity. The renal and pulmonary fractions contained 1–6(IV)NC1, and the placental fraction had a large amount of 1–2(IV)NC1 and a very small amount of 3–6(IV)NC1. Immunohistochemical study of bovine renal BM with the monoclonal antibodies revealed that bovine glomerular BM contained 1–5(IV) chains, but not the 6(IV) chain. The absence of 6(IV) chain in glomerular BM in bovine and in humans indicates that 6(IV) chain is not a target antigen of anti-GBM nephritis. Nephritogenicity is apparently a property of 3–5(IV)NC1.  相似文献   

17.
Summary The present study concerns the immunocytochemical localization of S-100 protein and subunits in the cells of human lymphoreticular tissue and their related tumours. The subunit is mainly localized in dendritic cells, most likely the dendritic reticulum cells (DRCs) located within the germinal centers, while the subunit is mainly localized in the interdigitating reticulum cells (IRCs) in the paracortical area and in Histiocytosis X cells. No immunoreactivity for either subunit was found in the majority of normal lymphocytes, macrophages, malignant lymphoma cells, or xanthoma cells.The DRCs and IRCs are generally considered to show different distribution in the lymphoid tissues and demonstrate some difference in their immunocytochemical and enzyme-histochemical features. It is suggested that S-100 subunits can be used as useful markers for these two types of dendritic cells and investigation of these subunits may provide more information for the study of human lymphoreticular system.  相似文献   

18.
We attempted to estimate in living adherent epithelial alveolar cells, the degree of structural and mechanical heterogeneity by considering two individualized cytoskeleton components, i.e., a submembranous cortical cytoskeleton and a deep cytoskeleton (CSK). F-actin structure characterizing each CSK component was visualized from spatial reconstructions at low and high density, respectively, especially in a 10-m-cubic neighborhood including the bead. Specific mechanical properties (Young elastic and viscous modulus E and ) were revealed after partitioning the magnetic twisting cytometry response using a double viscoelastic solid model with asymmetric plastic relaxation. Results show that the cortical CSK response is a faster ( 1 0.7s), softer (E1: 63-109 Pa), moderately viscous (1: 7-18 Pa s), slightly tensed, and easily damaged structure compared to the deep CSK structure which appears slower (2 min), stiffer (E2: 95-204 Pa), highly viscous (2: 760-1967 Pa s), more tensed, and fully elastic, while exhibiting a larger stress hardening behavior. Adding drug depolymerizing actin filaments decreased predominantly the deep CSK stiffness. By contrast, an agent altering cell–matrix interactions affected essentially the cortical CSK stiffness. We concluded that partitioning the CSK within cortical and deep structures is largely consistent with their respective functional activities. © 2003 Biomedical Engineering Society. PAC2003: 8716Ka, 8716Ac, 8380Lz  相似文献   

19.
Many B cell abnormalities have been reported in human immunodeficiency virus (HIV)-infected patients, including changes in the expression of , , and CD22 molecules on the cell surface. Phenotypic changes in these markers on B cells isolated from HIV-seropositive patients with high or low levels of plasma viremia were measured. The phenotypic changes in B cells isolated from such patients were compared with the markers on B cells isolated from HIV-seronegative individuals using three-color flow cytometry. HIV patients showed a reduction in the proportion of mature B cells isolated from peripheral blood mononuclear cells compared with B cells isolated from HIV-seronegative individuals. An increase in the proportion of B cells expressing both and molecules on the cell surface was also seen in association with high-HIV plasma viremia. A low plasma viral load was accompanied by a reduction in the proportion of B cells expressing both and molecules to a level comparable to those seen in HIV-seronegative individuals. HIV-seropositive individuals demonstrated an increase in the proportion of committed B cells, as indicated by an increase in the proportion of B cells expressing molecules. This observation may explain the poor humoral response of HIV seropositive patients to neo-antigens. Our results demonstrate that phenotypic changes indicative of in vivo B cell activation and an increase in immature cells are associated with HIV infection, particularly with a high plasma viral load. Phenotypic changes in B cell markers may correlate with functional deficits of B cells.  相似文献   

20.
    
Zusammenfassung Die aus den Fraktionen Hb A1 und Hb A1 hergestellten Globine liefern bei der Stärkegel Hochspannungselektrophorese praktisch identische Peptidketten-Auftrennungen. Die Aufspaltung der Hauptkomponente (Hb A1) des Erwachsenen-Hämoglobins (Hb A) in zwei Fraktionen (Hb A1, Hb A1) kann daher nicht durch eine Separation der- und-Peptidketten des Hämoglobinmoleküls bedingt sein. Vielmehr ist anzunehmen, daß das Molekül von Hb A1 in zwei symmetrische Hälften aufgespalten wird.  相似文献   

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