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21.
The efficacy of MC903, a vitamin D3 analogue, in reducing hyperproliferation as determined by levels of ornithine decarboxylase (ODC) was investigated in a double-blind study of 15 patients with chronic plaque psoriasis. The lesions of psoriasis were treated for 8 weeks with MC903 in one of two different cream bases or with a placebo cream. Biopsies were taken before and after treatment. In addition an uninvolved area of skin was treated during the last 3 weeks and this as well as control areas were then sellotape stripped and biopsied after 8 h. Clinical improvement was seen in eight out of 11 patients treated with MC903 but there was no reduction in the level of ODC in psoriatic lesions after 8 weeks of treatment. The levels of ODC in the tape-stripped uninvolved skin after 3 weeks of treatment with MC903 averaged 22.5 +/- 4.2 pmol/min/mg protein as compared to 58.6 +/- 12.6 pmol/min/mg protein (P = 0.004). The trauma-induced induction of ODC activity was markedly inhibited by the application of MC903. 相似文献
22.
23.
Expression of CD35 (CR1) and CD11b (CR3) on circulating neutrophils and eosinophils from allergic asthmatic children 总被引:3,自引:0,他引:3
C. BERENDS M. O. HOEKSTRA B. DIJKHUIZEN J. G. R. DE MONCHY J. GERRITSEN H. F. KAUFFMAN 《Clinical and experimental allergy》1993,23(11):926-933
Complement receptors on neutrophils and eosinophils play a role in activation and adhesion. During asthmatic reactions these receptors have been found elevated on circulating granulocytes. In the present study we compared the expression of CD35 (complement receptor type 1) and CD11b (complement receptor type 3) on neutrophils and eosinophils from asthmatic and non-asthmatic children. This was done in whole blood samples using depolarized light scattering for the discrimination of neutrophils and eosinophils. The non-stimulated expression as well as the upregulated expression of receptors by the chemotactic peptide N-formylmethionyl-leucyl-phenyl-alanine (fMLP) were studied. The results showed that without prior stimulation only the expression of CD35 on neutrophils was significantly elevated in children with asthma (P<0.05). After up-regulation with fMLP, the CD11b expression on neutrophils (P<0.005, fMLP: 0.002 microM) and eosinophils (P<0.05, fMLP: 0.02 microM) was significantly higher in asthmatic children than in the controls. These results indicate that the inducible expression of CD11b on neutrophils and eosinophils from allergic asthmatic children is primed in vivo. 相似文献
24.
J. A. HASRAT T. DE BRUYNE J.-P. DE BACKER G. VAUQUELIN A. J. VLIETINCK 《The Journal of pharmacy and pharmacology》1997,49(11):1145-1149
The fruit and the leaves of Annona muricata (Annonaceae) are used in traditional medicine for their tranquillizing and sedative properties. Extracts of the plant have been shown to inhibit binding of [3H]rauwolscine to 5-HTergic 5-HT1A receptors in calf hippocampus, and three alkaloids, annonaine ( 1 ), nornuciferine ( 2 ) and asimilobine ( 3 ), isolated from the fruit have been shown to have IC50 values of 3 μm , 9 μm and 5 μm , respectively, although in ligand-binding studies it was not possible to determine whether interaction of these ligands with the receptor was agonistic or antagonistic. This paper presents the results of functional assays of the alkaloids. The inhibition of cAMP accumulation was tested in NIH-3T3 cells stably transfected with the 5-HT1A receptor from man. None of the alkaloids showed antagonistic properties towards the 5-HT1A receptors because in the antagonistic tests no influence on the forskolin-stimulated increase of cAMP level was detected. Full agonistic properties were measured for all three compounds; the inhibition constants (Ki) for 1, 2 and 3 were < 10 μm . Inhibition of the binding of the radioligand to the 5-HT1A receptor was observed in every ligand-binding assay performed with the alkaloids; the Ki values for 1, 2 and 3 were in the μm range. These results imply that the fruit of Annona muricata possesses anti-depressive effects, possibly induced by compounds 1, 2 and 3 , and that in the past potent leads for the development of anti-depressive therapeutics have not been used. 相似文献
25.
Granular cell tumours rarely involve the lower respiratory tract. We report eight cases surgically resected at our institution. There were four females and four males, aged between 18 to 56 years (mean 40). One tumour associated with a peripheral lung adenocarcinoma was asymptomatic. The other lesions presented with obstructive pneumonitis (3 cases), haemoptysis (2), dyspnea (1) or cough (1). These tumours were tracheal (1) or bronchial (6) and one case was located in the lung parenchyma. Four cases were multicentric with associated lesions located in a bronchus (2), the oesophagus (1) or a mediastinal lymph node (1). All tumours, with the largest diameter ranging from 0.5–4.5 cm, were histologically invasive. The tumours were positive for S-100 protein, neuron specific enolase, KP1 (CD68) and vimentin. No tumour expressed desmin, keratin or p53 oncoprotein. Our study demonstrates that, in spite of marked anatomical and clinical polymorphism, the rare granular cell tumours of the lower respiratory tract have a constant histological appearance. Our observations confirm that large tumours (> 8–10 mm) usually extend beyond the tracheo-bronchial cartilages and, therefore, only surgical treatment may avoid recurrence. 相似文献
26.
Effect of exercise on plasma atrial natriuretic factor and cardiac function in men and women 总被引:1,自引:0,他引:1
J. E. DONCKIER P. M. DE COSTER M. BUYSSCHAERT P. LEVECQUE F. M. CAUWE C. M. BRICHANT A. C. BERBINSCHI J.-M. KETELSLEGERS 《European journal of clinical investigation》1988,18(4):415-419
In order to provide an integrated view of the physiology of atrial natriuretic factor (ANF) during exercise, we studied changes of its plasma concentrations in 13 normal subjects (seven males, six females) during three graded exercise levels and two periods of recovery (5 and 30 min), concomitantly with an assessment of cardiac function and ventricular volumes by multigated radionuclide angiography. Mean ANF levels (+/- SEM) increased in all patients at the second (P less than 0.002) and third (P less than 0.002) exercise levels, and after 5-min recovery (P less than 0.01): in males from 16 +/- 7 to 30 +/- 11 pg ml-1 at the third level, in females from 27 +/- 12 to 61 +/- 33 pg ml-1. Normal values were observed after 30-min recovery. Even if mean ANF levels were all higher in females, this difference did not reach statistical significance (P = 0.06). Significant decreases of ventricular volumes, as well as increases of ejection fraction and rate pressure product, were noted during exercise and were similar in both sexes. The kinetics of plasma ANF concentrations, compared with the increase of rate pressure product, was characterized by a latency and a remanence in recovery. This remanence, also present in the changes of ventricular volumes, supports the hypothesis that other factor(s) like catecholamines might still exert their influence after the exercise stops. 相似文献
27.
Intestinal intraepithelial lymphocytes (iIEL) are primarily CD8 cells and most of them have a CD28? phenotype, the phenotype of effector cytotoxic T cells. We asked whether the predominance of CD8+ CD28? T cells in the gut may result from peripheral blood T cells preferentially migrating to the iIEL compartment and adhering to iEC. Compared with CD4 cells, adhesion of resting CD8+ T cells to iEC cell lines was significantly higher. Adhesion could be blocked with a MoAb to gp180, a molecule expressed on iEC which is known to interact with CD8/lck. No significant difference in the level of adhesion was observed between CD8+ CD28+ and CD8+ CD28? T cells. Thus CD8 cells may preferentially migrate to the iIEL compartment, but loss of CD28 expression could occur in situ after migration. Consistent with this hypothesis, the CD8+ CD28? cells became enriched after co-culturing T cells with iEC cell lines and primary iEC. Induction of the CD8+ CD28? phenotype in cord blood and adult T cells was observed in co-cultures with iEC and also with mitogens and superantigens. In the latter case, CD28 down-modulation was seen specifically in the Vβ subset targeted by the superantigen, indicating that loss of CD28 expression is a direct result of T cell receptor (TCR)-mediated stimulation. The combined results suggest that CD8+ CD28? T cells are antigen experienced T cells, and that they may have a survival advantage in the presence of gut epithelial cells in vitro. This may contribute to the predominance of CD8+ CD28? T cells in the iIEL compartment. 相似文献
28.
Since the experimental infection by hydatid cysts ( Echinococcus granulosus ) in mice causes immunomodulation of the host, the effects of hydatid fluid (HF) and fractions of HF were compared in vitro and in vivo . Fractions of HF were obtained using ammonium sulphate precipitation, chloroform/methanol extraction and thin-layer chromatography (TLC). HF proved to be toxic to murine peritoneal macrophages in vitro , and when macrophages were incubated with the different fractions of HF, most toxicity was found in a single TLC-purified fraction with an adjuvant-like effect on the production of specific antibodies against bovine albumin and human red blood cells in mice. Treatment of mice with the toxin caused a drop in the percentage of peripheral blood lymphocytes. Flow-cytometric analysis showed that T-cells from toxin-treated mice had lower membrane-CD3, CD4 and CD8 density, and had higher percentages of CD8+ splenocytes and CD4+ thymocytes expressing CD25. The toxin caused a down-regulation of CD4 and CD8 expression on thymocytes in vitro , that was dependent on the presence of macrophages. The results may attribute to these toxins a role in the host-parasite relationship of hydatidosis. 相似文献
29.
R. DE BOER W. A. D. VAN DER HOEVEN S. O. STAPEL 《Clinical and experimental allergy》1995,25(8):765-770
Background: Fluctuations in the level of mite allergens in domestic house dust are the result of changes in the balance between synthesis, removal and decay. Purely physical forces as well as enzymatic degradation, mediated by house dust inhabiting microbes, may contribute to the decay of allergens in domestic dust. Knowledge about the speed of decay is essential for an understanding of the dynamics of allergen levels. Objective: The present study is a quantitative assessment of the speed of decay at nine combinations of temperature (15°C, 20°C and 25°C) and relative humidity (33%, 55% and 75%). Methods: Samples of mite infested material of an old rug were stored at these temperature/relative humidity-combinations for 6, 12 or 18 months, after the mites were killed by cither a freezing treatment or an acaricide (lindane). The microbes living in the rug presumably survive these treatments. Concentrations of Der p I and Der p II + Der f II. in extracts of the rug material, were measured by a radio immunoassay. Results: No significant changes in the levels of Der p I and Der p II +Der f II, could be detected even after 11/2 year at a high temperature and humidity. Conclusion: These findings incidate that mite allergens can be extremely stable under normal domestic circumstances. 相似文献
30.
Ivan Tkác Pierre-Gilles Henry Peter Andersen C Dirk Keene Walter C Low Rolf Gruetter 《Magnetic resonance in medicine》2004,52(3):478-484
An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models. 相似文献