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51.
Krauth MT Majlesi Y Florian S Bohm A Hauswirth AW Ghannadan M Wimazal F Raderer M Wrba F Valent P 《International archives of allergy and immunology》2005,138(2):111-120
BACKGROUND: Mast cells (MC) are important effector cells of allergic and inflammatory reactions in diverse organs. These cells interact with a number of other immune cells and structural cells in the tissues as well as with proinflammatory mediators and cytokines. The various interactions are considered to be mediated through distinct cell surface membrane receptors on MC. METHODS: In the present study, we have established the cell surface membrane phenotype of human gastrointestinal MC (HGMC) using a panel of monoclonal antibodies and indirect immunofluorescence staining techniques. RESULTS: HGMC were found to react with antibodies against CD29, CD33, CD44, CD45, CD47, CD54, CD55, CD58, CD63, CD117, CD147, CD151, CD172a, and CD203c. By contrast, HGMC did not express detectable amounts of CD1, CD2, CD4, CD5, CD14, CD15, CD16, CD22, CD24, CD25, CD26, CD27, CD28, CD31, CD32, CD34, CD35, CD88, or CD116. The alpha-chain of the IL-3 receptor (CD123) was detectable neither in resting HGMC nor in HGMC exposed to stem cell factor and interleukin-4. CONCLUSIONS: HGMC express a unique profile of surface antigens including the receptor for mast cell growth factor, adhesion-related molecules, and activation-linked membrane antigens. 相似文献
52.
Stimulation of murine lymphocyte blastogenesis by mitogens in heat-killed Histoplasma capsulatum yeast cells. 下载免费PDF全文
In vitro blastogenesis by normal murine splenocytes from several mouse strains has been detected after exposure to heat-killed Histoplasma capsulatum yeast cells. Maximal lymphocyte stimulation induced by 10(4) heat-killed cells resulted in 20- to 45-fold increases in [3H]thymidine uptake by splenocytes when compared with responses by normal unstimulated lymphocytes. The kinetics for this response to heat-killed H. capsulatum cells has shown peak mitogenesis 3 days after culture. Examination of the mitogenic potential of soluble antigen preparations from H. capsulatum has revealed stimulation of lymphocyte blastogenesis with yeast cell sonicates and autolysates but not substances from autoclaved yeast cells. The levels of lymphocyte blastogenesis induced by sonicates or autolysates were comparable to mitogen responses stimulated by heat-killed cells. Preliminary biochemical characterization of the mitogenic factor(s) associated with yeast cell sonicates show two peaks of activity, at 178,000 and less than 12,000 Mr, which have a protein or glycoprotein nature. Finally, analysis of lymphocyte blastogenesis in cultures enriched for selected lymphocyte subpopulations has shown that T lymphocytes are preferentially stimulated by yeast cell mitogens. 相似文献
53.
Endothelin and cardiac development 总被引:3,自引:0,他引:3
Luft FC 《Journal of molecular medicine (Berlin, Germany)》2002,80(11):685-686
54.
Theophylline and 3-isobutyl-1-methylxanthine, two cyclic nucleotide phosphodiesterase inhibitors, when fed to wild-typeDrosophila adults, cause the rapid decay of learning index after training in a shock-odor learning paradigm. The drugs practically do not affect the olfactory acuity of flies, hence they influence the learning/memory process itself. The time courses of memory decay resemble those of the memory mutantsrutabaga andamnesiac and, to a lesser extent,dunce
2 anddunce
M11. Theophylline further deteriorates the learning performance ofdunce
M11. Biochemical characterization of the inhibition of the two major phosphodiesterase isoenzymes inDrosophila by theophylline predicts only a slight inhibition of these enzymesin vivo, in accordance with the unchanged level of cAMP in wild-type fly heads during drug feeding. 8-Phenyltheophylline, an adenosine receptor antagonist in mammals, slightly retards memory decay in the wild-type. It is suggested that alkylxanthines induce memory decay inDrosophila by interfering with cAMP dynamics at more than one point of its metabolism.This work was supported by Grants OTKA and OKKFT Tt to P.F. 相似文献
55.
This study discusses three software tools, the first two aid in integrating sequence with an FPC physical map and the third automatically selects a minimal tiling path given genomic draft sequence and BAC end sequences. The first tool, FSD (FPC Simulated Digest), takes a sequenced clone and adds it back to the map based on a fingerprint generated by an in silico digest of the clone. This allows verification of sequenced clone positions and the integration of sequenced clones that were not originally part of the FPC map. The second tool, BSS (Blast Some Sequence), takes a query sequence and positions it on the map based on sequence associated with the clones in the map. BSS has multiple uses as follows: (1) When the query is a file of marker sequences, they can be added as electronic markers. (2) When the query is draft sequence, the results of BSS can be used to close gaps in a sequenced clone or the physical map. (3) When the query is a sequenced clone and the target is BAC end sequences, one may select the next clone for sequencing using both sequence comparison results and map location. (4) When the query is whole-genome draft sequence and the target is BAC end sequences, the results can be used to select many clones for a minimal tiling path at once. The third tool, pickMTP, automates the majority of this last usage of BSS. Results are presented using the rice FPC map, BAC end sequences, and whole-genome shotgun from Syngenta. 相似文献
56.
Pham MT Maitz MF Reuther H Muecklich A Prokert F Steiner G 《Journal of biomedical materials research. Part A》2004,71(1):16-24
The native extracellular matrix (ECM) laid down on silicon and titanium surfaces by osteoblast-like SAOS-2 cells was exposed by selective removal of cells. This type of material surface ECM-Si, ECM-Ti was shown to promote the nucleation of calcium phosphate from a simulated body fluid (SBF). Microscopic and spectroscopic results revealed the effect was associated with a collagen fiber-free extracellular matrix. 相似文献
57.
Horak F Stübner UP Zieglmayer R Harris AG 《The Journal of allergy and clinical immunology》2002,109(6):956-961
BACKGROUND: Unlike many antihistamines, desloratadine can reduce nasal congestion in patients with seasonal allergic rhinitis (SAR). OBJECTIVE: We compared the effects of 5 mg of desloratadine and placebo on nasal airflow and SAR symptoms, including nasal congestion, in response to grass pollen in an allergen-exposure unit. METHODS: In a randomized, double-blind, placebo-controlled, crossover trial, 47 subjects with histories of SAR received desloratadine or placebo every morning for 7 days and, after a 10-day washout period, were crossed over to the other treatment arm for 7 days. Subjects underwent a 6-hour allergen exposure on day 7 of each treatment period. Nasal airflow and nasal secretion weights were measured before and every 30 minutes during allergen exposure; SAR symptoms (including nasal congestion) were scored before exposure and every 15 minutes thereafter. RESULTS: Nasal obstruction, as measured by nasal airflow, was less severe with desloratadine than with placebo (P <.02). Individual and combined SAR symptom severity scores, including nasal congestion and sneezing, were significantly lower with desloratadine than with placebo (all P < or =.003). Within 30 minutes of allergen exposure, less severely decreased nasal airflow (P <.02), less nasal secretions (P <.001), and less severe symptoms, including nasal congestion (P <.002), rhinorrhea, and sneezing, occurred with desloratadine compared with placebo, and this continued throughout (0-6 hours) allergen exposure. Desloratadine was well tolerated, with an adverse event profile similar to that of placebo. CONCLUSION: In subjects with allergen-induced SAR symptoms, desloratadine significantly reduced the severity of nasal obstruction and accompanying complaints of nasal congestion and other SAR symptoms compared with the effects of placebo. 相似文献
58.
Charles Frèche Francisque Leynadier Friedrich Horak David Hide Fernando Duce Gracia Manfred Goos Claus Bachert Attila Horvath Eva Antosova Muriel Verrecchia Paul Ben Soussen 《Annals of allergy, asthma & immunology》2002,89(3):304-310
BACKGROUND: Mizolastine is a nonsedating H1 histamine receptor antagonist with additional antiallergic properties currently marketed in Europe for the treatment of seasonal and perennial allergic rhinitis (PAR) and urticaria. OBJECTIVE: This multicenter, randomized, double-blind, parallel-group study was conducted to evaluate the efficacy and safety of mizolastine in PAR compared with loratadine and placebo. METHODS: After a 1-week placebo run-in period, 428 adult PAR patients received placebo (146 of 428), mizolastine 10 mg (141 of 428), or loratadine 10 mg (141 of 428) once daily for 28 days. Symptoms were evaluated by patients and physicians using a total nasal score, evaluating itching, rhinorrhea, nasal blockade, and sneezing severity. RESULTS: Mizolastine treatment resulted in a significantly greater decrease in patient-rated total nasal score than placebo after 2 weeks (D14; -42%, P < 0.001) and at the end of the treatment period (-46%, P = 0.01), and significantly greater than that observed with loratadine at D14 (P = 0.031). No significant difference in change in total nasal score was observed between loratadine and placebo at 2- and 4-week visits. The global safety was satisfactory and the incidence of adverse events was similar in the three treatment groups. CONCLUSIONS: Mizolastine provides effective symptom relief in PAR together with a satisfactory safety profile. Improvement with mizolastine was significantly greater than placebo throughout the study despite a large placebo effect. Also mizolastine's effects were greater those observed with loratadine after 2 weeks of treatment. 相似文献
59.
Henrik Ewald Ole Mors Tracey Flint Ursula Friedrich Hans Eiberg Torben A. Kruse 《American journal of medical genetics. Part A》1995,60(5):386-392
The long arm of chromosome 11 is one of the most interesting regions in the search for major genes involved in the etiology of manic-depressive illness. Several candidate genes have been identified, including the gene encoding the dopamine D2 receptor, the M1 muscarinic receptor, and porfobillinogen deaminase. Furthermore, different families with co-segregation of psychiatric illness and structural chromosome abnormalities involving regions 11q21, 11q22.3, and 11q25 have been reported. Using narrow as well as broad phenotypic models, conservative genetic parameters, models with dominant or recessive modes of inheritance, and various methods to reduce misclassification, the present study did not find evidence for a major gene causing manic-depressive illness on the long arm of chromosome 11. In the broader phenotypic models multi-point analyses excluded at least 11q14 to 11q23.3, approximately 60 cM, even in one large family. Assuming homogeneity close linkage to DRD2 was excluded for all dominant models, and also in the affecteds-only analyses in the large family alone. © 1995 Wiley-Liss, Inc. 相似文献
60.