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Lympho-plasmacytic infiltrates in cryostat sections (resected small intestine or colon specimens and rectal biopsies) from 29 patients with Crohn's disease (CD) were studied with the immunoperoxidase and immunofluorescence technique, by means of specific anti-human lymphocyte globulin (ALG) and specific anti-human T-lymphocyte globulin (ATG). Control specimens were obtained from 16 patients with ulcerative colitis (UC) and 12 subjects without inflammatory bowel disease. Characteristic transmural inflammatory infiltrates in CD consisted mainly of lymphocytes. A wide variation of the relative T-cell proportion was observed. However, in contrast with UC, abundant numbers of T-lymphocytes in CD were often detected, particularly in the deeper layers of the bowel wall. Furthermore, in serial sections immunoglobulin-containing plasma cells were counted, using specific anti-IgA, -IgM, and -IgG antisera. A significant reduction of the IgA/IgM plasma cell-ratio was found in CD in comparison with UC and controls. Our results indicate that in CD a chronic cellular immune reaction is going on within the diseases gut, involving increased numbers of lymphocytes and particularly T-cells. It remains to be established whether a deficient IgA barrier has to be considered of primary pathogenetic importance.  相似文献   
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Δ10(18)-Acetylandromendenol, a new Substance isolated from Rhododendron ponticum Δ10(18)-Acetylandromedenol was found in the leaves of Rhododendron ponticum.  相似文献   
35.
Vesicoureteral reflux (VUR) remains one of the most controversial subjects in paediatric urology. Much literature has been published on VUR, making the understanding of this anomaly and its treatments quite opaque. Evidence-Based Medicine (EBM) should be helpful to clarify the various VUR approaches contained in the 6224 titles found on Medline using the keywords "vesicoureteral reflux" and "vesicoureteric reflux". These articles were critically reviewed and graded according to EBM scorings, with regard to their methodological designs. This review of VUR literature suggests that most of our knowledge is based on publications with a low level of evidence, and that EBM lacks arguments to support recommendations for VUR diagnostic and treatment. It appears yet that antenatal dilatation of the urinary tract and symptomatic urinary tract infections (UTI) justify VUR screening. Surgery should be discussed in recurrent UTIs or deterioration of renal function. There is no consensus in case of persistent asymptomatic VUR regarding indication and duration of antibio-prophylaxis, and selection of radical treatment.  相似文献   
36.
BACKGROUND: Human T-cell lymphotrophic virus (HTLV) type I has been linked to adult T-cell leukemia/lymphoma (ATL) and HTLV-I associated myelopathy (HAM). Transmission of HTLV by blood and organ transplantation has been documented, with some infections leading to clinical disease. Organ donors are tested for anti-HTLV antibodies and donor suitability is determined primarily by results from enzyme immunoassays (EIA). Confirmatory testing is not routinely performed, and the number of false positive organ donors is unknown. METHODS: In order to investigate the contemporary seroprevalence of anti-HTLV I/II antibodies among solid organ donors and determine the number of false positive samples, we tested 1,408 specimens from prospective organ donors in 2002 and 2003. All specimens were tested for anti-HTLV antibodies by a commercial EIA. Repeatedly reactive specimens underwent confirmatory testing using a commercial Western blot. RESULTS: There were 22 repeatedly EIA reactive donor specimens (1.56%). Five specimens did not undergo further testing because of case shutdown or insufficient sample quantity. HTLV I/II western blot confirmed six positives, whereas five were negative and six were indeterminate. The majority of confirmed specimens were positive for antibodies to HTLV-II. CONCLUSIONS: Our data shows that 29% of initially reactive specimens were false positives. With the increasing demand for organs, the unnecessary rejection of organs that are falsely positive for HTLV antibodies becomes of tremendous importance and stresses the need for timely confirmatory testing for HTLV.  相似文献   
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High titer antisera against the protective antigen (PA) from Bacillus anthracis were generated immunizing Balb/c mice two times intraperitoneally with PA in combination with lipopeptide adjuvant P3CSK4. The sera were able to protect the mouse macrophage cell line J774A.1 from an anthrax toxin challenge. We also tested the blood of anthrax vaccine-immunized persons for PA- and lethal factor (LF)-specific antibodies. An increased titer was found after three immunizations, and the sera were also able to protect the mouse macrophage cell line from a toxin challenge. For the preparation of human monoclonal antibodies, we used peripheral blood lymphocytes. After in vitro stimulation using PA or synthetic peptides derived from PA, B lymphocytes were immortalized by PEG fusion with the human mouse heteromyeloma cell line CB-F7. We obtained several clones producing high amounts of PA-specific immunoglobulin (Ig).  相似文献   
39.
Modification of the enzymatic functions of tissue transglutaminase (TG2) by anti-TG2 autoantibodies may play a role in manifestations of coeliac disease. Our aim was to evaluate the effect of coeliac autoantibodies on reactions catalysed by TG2 by a systematic biochemical approach, and in relation to observed clinical presentation type. Coeliac antibodies did not have significant inhibitory effect on transamidation/deamidation activity of TG2 as measured by amine-incorporation into solid and immobilised casein and by ultraviolet kinetic assay. In contrast, immunoglobulins from patients with severe malabsorption enhanced the reaction velocity to 105.4-242.2%. This activating effect was dose-dependent, most pronounced with immobilised glutamine-acceptor substrates, and correlated inversely with the basal specific activity of the enzyme and with dietary treatment. A similar activation could be demonstrated also with the TG2-specific fraction of autoantibodies and in transamidation activity assays which use fibronectin-bound TG2 and thereby mimic in vivo conditions. These results suggest that coeliac antibodies may stabilise the enzyme in a catalytically advantageous conformation. GTPase activity of TG2 decreased to 67.0-73.4% in the presence of antibodies raising the possibility that inhibition of GTPase activity may affect cellular signalling in case coeliac autoantibodies would reach intracellular compartments.  相似文献   
40.
Atherosclerotic cardiovascular mortality is increased in rheumatoid arthritis (RA) patients. We evaluated the association of inflammatory response with platelet, endothelial, coagulation activation parameters; and subclinical atherosclerosis in RA patients. We included 27 RA patients (21 female; six male) and 19 healthy subjects (14 female; five male). Disease activity score (DAS28) in RA patients was calculated; and patients were divided into two groups as active and inactive. Flow cytometry was used to determine platelet CD62P expression, platelet microparticles (PMP), platelet-monocyte (PMC) and platelet-neutrophil complexes (PNC). Plasma E-selectin, thrombin-antithrombin (TAT) complex, and serum sCD40L levels were determined by ELISA. The intima-media thickness (IMT) of carotid arteries was determined by B-mode ultrasonography. In RA patients, platelet CD62P expression (p < 0.001), PMC (p = 0.037) and sCD40L (p < 0.001) levels were increased when compared to the control group. PNC (p = 0.07) and TAT levels (p = 0.1) were non-significantly higher, and PMP level (p = 0.075) was nonsignificantly lower in RA patients. Soluble E-selectin level was significantly higher in the active RA group than in the inactive RA group (p = 0.009). There was no correlation between carotid IMT and activity markers, the evaluated parameters (p > 0.05).The increase in markers of active platelets, CD62P and sCD40L, and PMC levels might be associated with the increased cardiovascular mortality in RA. Nevertheless, none of these parameters were associated with carotid IMT: this suggests that one cross-sectional value might not be a good marker for atherosclerosis.  相似文献   
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