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41.
Sleep deprivation exerts antidepressant effects after only one night of deprivation, demonstrating that a rapid antidepressant response is possible. In this report we tested the hypothesis that total sleep deprivation induces an increase in extracellular serotonin (5-HT) levels in the hippocampus, a structure that has been proposed repeatedly to play a role in the pathophysiology of depression. Sleep deprivation was performed using the disk-over-water method. Extracellular levels of 5-HT were determined in 3 h periods with microdialysis and measured by high performance liquid chromatography coupled with electrochemical detection. Sleep deprivation induced an increase in 5-HT levels during the sleep deprivation day. During an additional sleep recovery day, 5-HT remained elevated even though rats displayed normal amounts of sleep. Stimulus control rats, which had been allowed to sleep, did not experience a significant increased in 5-HT levels, though they were exposed to a stressful situation similar to slee-deprived rats. These results are consistent with a role of 5-HT in the antidepressant effects of sleep deprivation. 相似文献
42.
Airway eosinophilia and expression of interleukin-5 protein in asthma and in exacerbations of chronic bronchitis 总被引:6,自引:0,他引:6
M. SAETTA A. DI STEFANO P. MAESTRELLI G. TURATO CE. MAPP M. PIENO G. ZANGUOCHI G. DEL PRETE† L. M. FABBRI 《Clinical and experimental allergy》1996,26(7):766-774
Background An increased nutnber of eosinophils in the bronchial mucosa has been demonstrated both in asthma and in exacerbations of chronic bronchitis. Oiyective To investigate whether the airway eosinophilia present in asthma and in chronic bronchitis during exacerbations is associated with interleukin (IL)-5 protein expression in the bronchial mucosa. Methods We obtained bronchial biopsies in 18 subjects with asthma (four intrinsic, seven extrinsic and seven occupational) and in II subjects with chronic bronchitis examined during an exacerbation. The findings were compared wilh those of bronchial biopsies from 10 subjects with chronic bronchitis examined under baseline conditions and from seven normal subjects, taken as controls. By immunohistochemistry, we assessed the expression of IL-5 protein and the number of eosinophils (EG2), mast cells ftryptase), and T-lymphocytes (CD3) in the submucosa. Results As compared with controls, the number of eosinophils was increased to a similar degree in both asthma (P < 0.001) and in exacerbations of ehronic bronchitis (P < 0.001). whereas the number of I L-5 immunopositive cells was increased significantly only in asthma (P < 0.01). No diflerences were observed in the number of tnast cells and T-lymphocytes between the four groups of subjects examined. Conciusions This study shows that the degree of airway eosinophilia is similar in asthma and in exacerbations of ehronic bronchitis, but only in asthma is it associated with an increased expression of I L-5 protein in the bronchial tnucosa. 相似文献
43.
Five novel mutations in the L1CAM gene in families with X linked hydrocephalus. 总被引:2,自引:2,他引:2
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S M Gu U Orth A Veske H Enders K Klunder M Schlosser W Engel E Schwinger A Gal 《Journal of medical genetics》1996,33(2):103-106
Five novel mutations have been identified in the gene encoding L1CAM, a neural cell adhesion protein, in families with X linked hydrocephalus (XHC). Interestingly, all five mutations are in the evolutionarily highly conserved Ig-like domains of the protein. The two frameshift mutations (52insC and 955delG) and the nonsense mutation (Trp276Ter) most probably result in functional null alleles and complete absence of L1CAM at the cell surface. The two missense mutations (Tyr194Cys and Pro240Leu) may considerably alter the structure of the L1CAM protein. These data provide convincing evidence that XHC is genetically extremely heterogeneous. 相似文献
44.
In vivo and in vitro studies on possible pathogenic mechanisms of Actinomyces viscosus. 总被引:1,自引:6,他引:1
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Actinomycotic infections are characterized by long-term inflammatory lesions containing large numbers of polymorphonuclear leukocytes (PMNs) and mononuclear cells. The pathogenic mechanisms involved in these lesions are not understood. Homogenates of Actinomyces viscosus (AVIS) induce an acute inflammatory response with a predominance of PMNs within 6 h after injection into the footpads of nonimmunized mice. These homogenates, when tested in vitro, contain potent chemotactic activity for human PMNs. In vitro chemotactic activity for human monocytes is weak but statistically significant (P less than 0.025). Doses of AVIS, which alone have little chemotactic activity, cause the generation of PMN chemotactic activity in fresh, but not complement-inactivated, serum. The injection of AVIS into the footpads of immunized mice induces an acute inflammatory response followed within 48 h by a mononuclear cell infiltrate, suggesting that factors affecting monocyte accumulation are generated by the immune host in response to challenge with the bacterial antigens. These findings indicate that the pathogenicity of the Actinomyces may result in part from (i) their direct chemotactic effect on PMNs, (ii) their cytotaxigenic effects on serum, and (iii) their ability to stimulate host immune cells to produce and release mediators of inflammation. 相似文献
45.
van den Engel NK an Haack M Martin S Kolb H 《Journal of molecular medicine (Berlin, Germany)》2002,80(5):301-308
Adhesion molecules are important for leukocyte extravasation and for the delivery of costimulatory signals in T cell activation. We therefore interfered in the immune process leading to islet inflammation in diabetes prone NOD mice by oral vaccination with plasmid DNA encoding soluble ICAM-1. Female NOD mice were treated orally with ICAM-1, TGF-beta, or control plasmid DNA and received a single injection of cyclophosphamide for synchronization and acceleration of the disease process in the pancreas. Quantitative RT-PCR analysis of pancreatic mRNA showed that cyclophosphamide induced the expression of Th1 cytokines (IFN-gamma and IL-12p40) in vehicle- or control plasmid-treated mice. Treatment with ICAM-1 and TGF-beta DNA resulted in increased levels of IL-10 mRNA in the pancreas, indicating an anti-inflammatory regulatory immune response. Histological analysis of pancreatic islets showed that the DNA treatment did not alter islet infiltration in response to cyclophosphamide. Hence vaccination with the ICAM-1 plasmid had not suppressed leukocyte migration but rather modulated lymphocyte activity, similarly as seen for the TGF-beta-encoding plasmid. Neither of the three plasmids caused recognizable changes in cytokine expression in the small intestine, Peyer's patches, or mesenteric lymph nodes. We conclude that oral vaccination with DNA encoding immunoregulatory molecules such as ICAM-1 and TGF-beta represents an approach for modulating the ongoing inflammatory process in the pancreas of diabetes prone NOD mice. 相似文献
46.
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48.
Reiss J Bonin M Schwegler H Sass JO Garattini E Wagner S Lee HJ Engel W Riess O Schwarz G 《Molecular genetics and metabolism》2005,85(1):12-20
Molybdenum cofactor (Moco)-deficiency is a lethal autosomal recessive disease, for which until now no effective therapy is available. The biochemical hallmark of this disorder is the inactivity of the Moco-dependent sulfite oxidase, which results in elevated sulfite and diminished sulfate levels throughout the organism. In humans, Moco-deficiency results in neurological damage, which is apparent in untreatable seizures and various brain dysmorphisms. We have recently described a murine model for Moco-deficiency, which reflects all enzyme and metabolite changes observed in the patients, and an efficient therapy using a biosynthetic precursor of Moco has been established in this animal model. We now analyzed these mice in detail and excluded morphological brain damage, while expression analysis with microarrays indicates a massive cell death program. This neuronal damage appears to be triggered by elevated sulfite levels and is ameliorated in affected embryos by maternal clearance. 相似文献
49.
Reinehr T Jauch A Zoll B Engel U Bartels I Andler W 《American journal of medical genetics》2001,102(1):81-85
Deletions of the terminal Xp regions, including the short-stature homeobox (SHOX) gene, were described in families with hereditary Turner syndrome and Léri-Weill syndrome. We report on a 10-2/12-year-old girl and her 37-year-old mother with short stature and no other phenotypic symptoms. In the daugther, additional chromosome material was detected in the pseudoautosomal region of one X chromosome (46,X,add(Xp.22.3)) by chromosome banding analysis. The elongation of the X chromosome consisted of Giemsa dark and bright bands with a length one-fifth of the size of Xp. The karyotype of the mother demonstrated chromosome mosaicism with three cell lines (46,X,add(X)(p22.3) [89]; 45,X [8]; and 47,X,add(X)(p22.3), add(X)(p22.3) [2]). In both daughter and mother, fluorescence in situ hybridization (FISH), together with data from G banding, identified the breakpoints in Xp22.1-3 and Xq26, resulting in a partial trisomy of the terminal region of Xq (Xq26-qter) and a monosomy of the pseudoautosomal region (Xp22.3) with the SHOX gene and the proximal region Xp22.1-3, including the steroidsulfatase gene (STS) and the Kallmann syndrome region. The derivative X chromosome was defined as ish.der(X)t(X;X)(p22.1-3;q26)(yWXD2540-, F20cos-, STS-, 60C10-, 959D10-, 2771+, cos9++). In daughter and mother, the monosomy of region Xp22.1-3 is compatible with fertility and does not cause any other somatic stigmata of the Turner syndrome or Léri-Weill syndrome, except for short stature due to monosomy of the SHOX gene. 相似文献
50.