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41.
Distinct events in the virus-stimulated T-cell-mediated cytotoxicity (V-CMC) have been investigated: 1.) The induction of V-CMC is possible by immunizing mice with infectious as well as UV-inactivated virus (parainfluenza type 1 strain 6/94), or with virus-infected cells either compatible or imcompatible with the recipient. 2.) Recognition of viral antigens by the effector cells occurs independently of the H2 environment: Fractionation of effector cells on columns loaded with virus-infected cells eliminates virus-specific cytotoxic cells. Effector cells and cells on the column need not share H-2 antigens. The findings are discussed with regard to the H2 restriction of the virus induced T-cell mediated cytotoxicity.This paper was presented at the Sixteenth Symposium of the European Association Against Virus Diseases in Amsterdam, September 7–9, 1977 相似文献
42.
Petersson LM Nordin K Glimelius B Brekkan E Sjödén PO Berglund G 《Psychosomatic medicine》2002,64(6):971-980
OBJECTIVE: The major aim was to explore the extent to which the Miller Behavioral Style Scale (MBSS) can be used to differentiate cancer patients who are likely to benefit from rehabilitation efforts with a strong information component from those who are not. METHODS: Newly diagnosed patients with breast, gastrointestinal, or prostate cancer (N = 442) were included in a randomized, prospective study of the effects (on anxiety, depression, intrusion, avoidance) of rehabilitation approximately 4 months after diagnosis as compared with control patients. Patients were classified as "monitors" or "blunters" on the basis of the MBSS (368 patients, 83%, completed the MBSS). RESULTS: The expected interaction at postintervention between coping style and experimental condition (ie, rehabilitation or control) was found only for avoidance among breast and prostate cancer patients. Assignment to the rehabilitation or control condition was of no importance for outcome among blunters. Among monitors, the response pattern differed between breast and prostate cancer patients. Prostate cancer monitors seemed to benefit from rehabilitation on all outcome measures, whereas intrusion and avoidance were reduced among breast cancer patients in the control condition. This interaction of diagnosis with condition (rehabilitation or control) among monitors is suggested to be due to demands for diagnosis-specific information during diagnostic work, in the period just after diagnosis, and before treatment decision. CONCLUSIONS: Only the monitor concept seems useful for predicting response to cancer rehabilitation with a strong information component. However, whether rehabilitation is of benefit depends also on other factors. 相似文献
43.
Gilissen LJ Bolhaar ST Matos CI Rouwendal GJ Boone MJ Krens FA Zuidmeer L Van Leeuwen A Akkerdaas J Hoffmann-Sommergruber K Knulst AC Bosch D Van de Weg WE Van Ree R 《The Journal of allergy and clinical immunology》2005,115(2):364-369
BACKGROUND: Apple allergy is dominated by IgE antibodies against Mal d 1 in areas where birch pollen is endemic. Apples with significantly decreased levels of Mal d 1 would allow most patients in these areas to eat apples without allergic reactions. OBJECTIVE: The aim of this study was to inhibit the expression of Mal d 1 in apple plants by RNA interference. METHODS: In vitro -grown apple plantlets were transformed with a construct coding for an intron-spliced hairpin RNA containing a Mal d 1-specific inverted repeat sequence separated by a Mal d 1-specific intron sequence. The presence of the construct in transformants was checked by PCR. Expression of Mal d 1 in leaves was monitored by prick-to-prick skin testing in 3 patients allergic to apples and by immunoblotting with a Mal d 1-reactive mAb and with IgE antibodies against Mal d 1. RESULTS: After transformation, plantlets were selected on the basis of having a normal phenotype and growth rate. With PCR, in 6 of 9 selected plantlets, the presence of the gene-silencing construct was demonstrated. By skin prick test it was shown that a wild-type plantlet had significantly ( P < .05) higher allergenicity than 5 of the transformants. Reduction of expression of Mal d 1 was confirmed by immunoblotting. In wild-type and unsuccessful transformants, a strong band was detected with Mal d 1-reactive mAb 5H8 at the expected apparent M r of 17 kDa. This band was virtually absent in the transformants that carried the gene-silencing construct. With human IgE antibodies, the same observations were made. CONCLUSIONS: Mal d 1 expression was successfully reduced by RNA interference. This translated into significantly reduced in vivo allergenicity. These observations support the feasibility of the production by gene silencing of apples hypoallergenic for Mal d 1. 相似文献
44.
45.
Wolff N Yannai S Karin N Levy Y Reifen R Dalal I Cogan U 《The Journal of allergy and clinical immunology》2004,114(5):1151-1158
BACKGROUND: The increased consumption of foods containing sesame seeds is paralleled by an increase in reported sesame-induced allergic reactions. OBJECTIVE: This study aimed at identifying and characterizing the linear B-cell epitopes of the 14-kd beta-globulin, the major allergen of sesame seed. METHODS: A peptide containing 71 amino acids (peptide B) was previously identified by us as the IgE-binding region on beta-globulin. To determine the amino acid sequence of the IgE-binding sites on peptide B, we synthesized overlapping peptides 20 and 10 amino acid residues long that span the entire length of peptide B, which were offset from each other by 10 and 2 amino acid residues, respectively. Sera from 20 subjects given diagnoses of allergy to sesame beta-globulin served to identify the epitopes by using the dot-blot test. RESULTS: At least 9 different IgE-recognition sites were identified on peptide B. Three of them, numbers 2, 3, and 13 (corresponding to amino acids 46-55, 48-57, and 76-86, respectively, in the beta-globulin sequence), appeared to be immunodominant IgE-binding epitopes. Also, these peptides were best recognized in terms of intensity of response. There was no obvious sequence motif shared by the 9 different IgE-binding epitopes of beta-globulin. However, approximately 60% of the amino acids represented in the epitopes are hydrophobic residues. CONCLUSION: Identification of the IgE-binding epitopes might provide a better understanding of the functional role the allergens play in the disease and might have implications for immunodiagnosis and probably immunotherapy. 相似文献
46.
Requirement for tumor necrosis factor receptor 2 expression on vascular cells to induce experimental cerebral malaria
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Stoelcker B Hehlgans T Weigl K Bluethmann H Grau GE Männel DN 《Infection and immunity》2002,70(10):5857-5859
Using tumor necrosis factor receptor type 2 (TNFR2)-deficient mice and generating bone marrow chimeras which express TNFR2 on either hematopoietic or nonhematopoietic cells, we demonstrated the requirement for TNFR2 expression on tissue cells to induce lethal cerebral malaria. Thus, TNFR2 on the brain vasculature mediates tumor necrosis factor-induced neurovascular lesions in experimental cerebral malaria. 相似文献
47.
cDNA arrays are a powerful tool for the identification of differentially expressed genes in malignant tumors. We used this technique to study the gene expression profiles of anaplastic large cell lymphoma (ALCL) and Hodgkin's disease (HD). Gene expression of 11 lymphoma cell lines was analyzed covering 1176 cDNA sequences. Comparing these data to the expression profiles of B- and T-lymphocytes, we identified 27 genes that were deregulated in all cell lines or in a particular entity. For the establishment of gene expression profiles the 27 genes were assigned to four groups composed of genes deregulated in (i) all lymphoma cell lines, (ii) ALCL and HD, (iii) only HD, and (iv) ALCL exclusively. Our results indicate that ALCL and HD share the differential expression of at least five genes. In addition, both entities are characterized by the differentially deregulated expression of four genes in HD and seven genes in ALCL. Because the expression profiling was performed on cell lines, further studies are needed to clarify the biological significance of the differentially expressed genes. 相似文献
48.
Krustrup P Söderlund K Mohr M González-Alonso J Bangsbo J 《Pflügers Archiv : European journal of physiology》2004,449(1):56-65
To investigate recruitment of slow-twitch (ST) and fast-twitch (FT) muscle fibres, as well as the involvement of the various quadriceps femoris muscle portions during repeated, intense, one-legged knee-extensor exercise, 12 healthy male subjects performed two 3-min exercise bouts at ~110% maximum thigh O2 consumption (EX1 and EX2) separated by 6 min rest. Single-fibre metabolites were determined in successive muscle biopsies obtained from the vastus lateralis muscle (n=6) and intra-muscular temperatures were continuously measured at six quadriceps muscle sites (n=6). Creatine phosphate (CP) had decreased (P<0.05) by 27, 73 and 88% in ST fibres and 25, 71 and 89% in FT fibres after 15 and 180 s of EX1 and after 180 s of EX2, respectively. CP was below resting mean–1 SD in 15, 46, 84 and 100% of the ST fibres and 9, 48, 85 and 100% of the FT fibres at rest, after 15 and 180 s of EX1 and after 180 s of EX2, respectively. A significant muscle temperature increase (Tm) occurred within 2–4 s at all quadriceps muscle sites. Tm varied less than 10% between sites during EX1, but was 23% higher (P<0.05) in the vastus lateralis than in the rectus femoris muscle during EX2. Tm in the vastus lateralis was 101 and 109% of the mean quadriceps value during EX1 and EX2, respectively. We conclude that both fibre types and all quadriceps muscle portions are recruited at the onset of intense knee-extensor exercise, that essentially all quadriceps muscle fibres are activated during repeated intense exercise and that metabolic measurements in the vastus lateralis muscle provide a good indication of the whole-quadriceps muscle metabolism during repeated, intense, one-legged knee-extensor exercise. 相似文献
49.
Outbreak of carbapenem-resistant Acinetobacter baumannii producing the OXA-23 enzyme in Curitiba,Brazil 总被引:19,自引:0,他引:19
Dalla-Costa LM Coelho JM Souza HA Castro ME Stier CJ Bragagnolo KL Rea-Neto A Penteado-Filho SR Livermore DM Woodford N 《Journal of clinical microbiology》2003,41(7):3403-3406
Carbapenem-resistant Acinetobacter baumannii isolates were obtained from eight patients in two hospitals in Curitiba, Brazil. The isolates were multiresistant, belonged to a single strain, and produced the OXA-23 carbapenemase. Treatment options were limited, although the isolates were susceptible to polymyxin B in vitro. The strain contributed to the deaths of five patients. 相似文献
50.