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991.
Lymphocytes in Peyer patches regulate clinical tolerance in a murine model of food allergy 总被引:2,自引:0,他引:2
Frossard CP Tropia L Hauser C Eigenmann PA 《The Journal of allergy and clinical immunology》2004,113(5):958-964
BACKGROUND: Food allergy can lead to severe, potentially life-threatening anaphylactic reactions. To generate efficient strategies aimed at an active cure, a better understanding of the pathogenic mechanisms is strongly needed. OBJECTIVE: To investigate T-cell-related mechanisms of food allergy and tolerance to beta-lactoglobulin (BLG) in gut-associated lymphoid structures. METHODS: Beta-lactoglobulin-specific IgG1, IgG2a, and IgE in serum from mice anaphylactic to BLG were analyzed by ELISA and compared with those obtained in mice actively tolerized to BLG. The number of Ab-secreting cells in the spleen and in Peyer patches was determined by ELISPOT. The numbers of cytokine-producing cells after antigen-specific activation were measured by the same method. Furthermore, mesenteric lymph node cells and Peyer patches cells were transferred to naive mice, and Ab production as well as Ab-secreting cells were measured. RESULTS: Serum IgG1 and IgE Ab titers as well as IL-4-producing cell numbers were strongly increased in anaphylactic mice. IL-10 was found in Peyer patch cells from tolerant mice after BLG activation but not in anaphylactic mice. Peyer patch cells, in contrast to mesenteric lymph node cells, proliferated weakly in anaphylactic mice after antigen activation, and activation of Peyer patches was partially inhibited by tolerization. CONCLUSIONS: Our data suggest a specific role for lymphocytes in Peyer patches in tolerance to BLG. Low IL-10 production in Peyer patches may favor symptoms of food allergy. 相似文献
992.
Chen H Katz PP Eisner MD Yelin EH Blanc PD 《The Journal of allergy and clinical immunology》2004,114(4):845-850
BACKGROUND: Factors affecting health-related quality of life (HRQOL) in adult rhinitis have not been well described. OBJECTIVE: To understand how symptom severity, physical functioning, psychological distress, and perceived control of disease relate to HRQOL in a population-based sample of adults with rhinitis. METHODS: We conducted telephone interviews in 109 adults with rhinitis recruited via random digit dialing. We assessed HRQOL by using the Rhinosinusitis Disability Index, physical functioning by using the physical component score of the Short Form-12, and psychological distress by using the Center for Epidemiologic Studies Depression Scale. To evaluate the role of patient-perceived control of disease in rhinitis, we developed a new 8-item instrument, the Perceived Control of Rhinitis Questionnaire. RESULTS: Lower HRQOL correlated with greater symptom severity ( r=0.57), poorer physical functioning ( r=-0.41), greater psychological distress ( r=0.44), and less perceived control ( r=-0.53). In a multivariate model, symptom severity ( P < .001), psychological distress ( P <.001), and perceived control ( P <.001) were all independent predictors of HRQOL. Adding functional and psychosocial measures to a base model with demographics and disease severity explained an additional 26% of variance in HRQOL. CONCLUSIONS: Although disease severity is an important factor in HRQOL, psychosocial factors, such as perceived control of disease, explain a substantial amount of the variability in HRQOL among adults with rhinitis. 相似文献
993.
Drancourt M Bodaghi B Lepidi H Le Hoang P Raoult D 《Journal of clinical microbiology》2004,42(4):1822-1825
Bartonella henselae uveitis was diagnosed in a 40-year-old woman with underlying HLA-B27 uveitis on the basis of immunodetection and molecular detection of the organism, a Marseilles genogroup and a CAL-1 genotype strain, in the vitreous fluid. This case illustrates that B. henselae should be included in the differential diagnosis of uveitis and the usefulness of immunodetection for rapid and specific diagnosis. 相似文献
994.
995.
Camilleri-Broët S Fermé C Berger F Lepage E Bain S Brière J Marmey B Gaulard P Audouin J 《Virchows Archiv : an international journal of pathology》2004,445(4):344-346
No reliable marker still exists for predicting those patients with Hodgkins lymphoma (HL) who may experience a fatal outcome. Among the factors tested in the literature, it has been suggested that the number of activated cytotoxic T cells may represent a prognostic marker in HL. In 244 samples from patients with stage-IIIB/IV HL issued from the GELA H89 trial, we have analysed TiA1 expression on Reed Sternberg (RS) cells as well as the percentage of positive reactive lymphocytes. There were 34 cases (13.7%) that showed TiA1 expression on tumour cells; whereas, in 32 cases (13.1%), TiA1-positive reactive lymphocytes represented more than 30% of the reactive lymphocytes. LMP-1 was found co-expressed with TiA1 in 10 of the 22 positive cases tested. Our study confirms that a subset of classical HL expresses cytotoxic proteins, with occasional co-expression of CD20. In stage-IIIB/IV disease, neither TiA1 expression by RS cells nor a high percentage of TiA1-positive reactive lymphocytes have a prognostic impact on outcome. 相似文献
996.
997.
Maassen MM Rodriguez Jorge J Herberhold S Vonthein R Zimmermann R Baumann I Brosch S Mauz PS Pfister M Zalaman IM Löwenheim H Zenner HP 《The Laryngoscope》2004,114(11):2012-2020
OBJECTIVES: The aim of the study was to evaluate the safety and feasibility of piezoelectric malleus vibration audiometer (MVA), which presents micromechanical vibrations to the umbo membranae tympani. STUDY DESIGN: Phase I study performed in a tertiary referral center (University Hospital). METHODS: The coupling rod of the MVA was moved slowly through the outer ear canal toward the eardrum with a micromanipulator. Coupling was completed when the rod tip touched the umbo membranae tympani. Basic audiologic measures of sound threshold obtained with direct stimulation of the malleus are presented. We used MANOVA (multivariate repeated measures ANOVA) to investigate the repeatability of MVA thresholds from one day to the other and when decoupling and retracting the coupling rod 2 mm off the umbo. We also selected the MANOVA to test for unwanted bone-conduction threshold shifts after MVA application. We assessed normality of the data by quantile-quantile plots of the residuals. RESULTS: Twenty-eight male and 10 female subjects with normal hearing, 22.2 to 34.6 years old (median age, 27.2 yr) underwent an examination. Thirty-six subjects underwent MVA, because 2 of the 38 subjects who volunteered for the study have not undergone the procedure due to the external auditory canal anatomy preventing application of the MVA. The results show that it is possible to safely and reliably measure thresholds of direct vibration of the ossicular chain. Using pure tone audiograms, no pure tone bone- and/or air-conduction threshold shifts occurred after the procedure. None of the subjects reported any other ear-related symptoms such as vertigo, tinnitus, or dizziness. Geometric mean vibratory displacements at threshold ranged from 0.55 nm at 250 Hz to 0.03 nm at 6 kHz. MANOVA demonstrated a repeatability of MVA thresholds. CONCLUSION: Malleus vibration audiometry will not allow exact linkage of actual implantable hearing aid. But the present study demonstrates that MVA can provide an audiometric tool for assessing ossicular function and integrity prior to implantation of an electronic hearing amplifier. 相似文献
998.
999.
1000.
Lichtman AH Leung D Shelton CC Saghatelian A Hardouin C Boger DL Cravatt BF 《The Journal of pharmacology and experimental therapeutics》2004,311(2):441-448
Fatty acid amide hydrolase (FAAH) is the primary catabolic regulator of several bioactive lipid amides in vivo, including the endogenous cannabinoid anandamide and the sleep-inducing substance oleamide. Inhibitors of FAAH are considered a potential therapeutic approach for the treatment of several nervous system disorders, including pain, anxiety, and insomnia. However, for FAAH inhibitors to achieve clinical utility, they must not only display efficacy in vivo but also selectivity for this enzyme relative to the numerous other serine hydrolases present in mammalian proteomes. Here, we report a general strategy for evaluating the pharmacological activity and target specificity of FAAH inhibitors and its implementation to develop the first class of selective reversible inhibitors of this enzyme that are highly efficacious in vivo. Using a series of functional proteomics, analytical chemistry, and behavioral pharmacology assays, we have identified a class of alpha-keto-heterocycles that show unprecedented selectivity for FAAH relative to other mammalian hydrolases, and, when administered to rodents, raise central nervous system levels of anandamide and promote cannabinoid receptor 1-dependent analgesia in several assays of pain sensation. These studies provide further evidence that FAAH may represent an attractive therapeutic target and describe a general route by which inhibitors of this enzyme can be optimized to achieve exceptional potency, selectivity, and efficacy in vivo. 相似文献