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51.
This study investigated the effect of adenosine in the forced swimming test (FST) and the tail suspension test (TST) in mice, and the contribution of adenosine A1 and A2A receptors to adenosine's antidepressant-like effect. The immobility time in the FST was reduced by adenosine given either by i.p. (5-10 mg/kg) or i.c.v. (0.01-10 microg/site) route. Adenosine (1-10 mg/kg, i.p.) also produced an antidepressant-like effect in the TST. No treatment affected locomotion in an open-field. The anti-immobility effect of adenosine (10 mg/kg, i.p.) in the FST was prevented by i.p. pretreatment of mice with caffeine (3 mg/kg), DPCPX (2 mg/kg) and ZM241385 (1 mg/kg). CHA (0.05 mg/kg, i.p.) and DPMA (1-5 mg/kg, i.p.) also produced an antidepressant-like effect in the FST. This is the first report of an antidepressant-like effect of adenosine in mice, apparently mediated through an interaction with A1 and A2A receptors.  相似文献   
52.
Oner S  Ercan F  Arbak S 《Acta histochemica》2004,106(3):207-217
Small bowel is one of the organs that can in principle be transplanted. Optimum preservation of the organ is essential for the success of transplantation. The aim of the present study is the investigation of time-related morphological changes of rat small bowel during preservation in hypothermic Euro-Collins (EC) and Ringer's lactate (RL) solution using light microscopy and transmission electron microscopy to evaluate the integrity of intercellular complexes of mucosal epithelium, one of the tissues of the intestine that is most susceptible to ischemia. Small bowels were perfused with either EC, RL solution or physiological saline solution and were placed in the different preservation solutions at 4 degrees C for 0, 3, 6 and 12 h. The results of our study suggest that both preservation solutions are suitable for short-term preservation of the small bowel although RL solution is more effective than EC solution. However, we conclude that further improvement of preservation solutions and/or techniques are needed to perform long-term preservation.  相似文献   
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Recent studies have revealed that dynamic biomechanical forces can exert antiinflammatory and antiproteolytic effects on fibrocartitage. Whether the effects of mechanical strain also involve stimulation of the insulin-like growth factor (IGF) system and, therefore, of growth and repair of fibrocartilage has yet to be determined. The objective of this in vitro study was to determine if continuous biophysical strain regulates the gene expression of IGF1, IGF2, IGF1 receptor (IGF1R), insulin receptor substrate (IRS1), and IGF-binding proteins (IGFBP) 3 and 5 in cells from the fibrocartilaginous disc of the temporomandibular joint (TMJ). Rat TMJ disc cells were subjected to continuous biophysical strain (3% and 20%) for 4 and 24 h. Subsequently, RNA was extracted and real-time PCR was performed using an iCycler iQ detection system to analyze the gene expression of the IGF system. The gene expression of IGF1, IGF2, IGF1R, IRS1, IGFBP3, and IGFBP5 was significantly (p < 0.05) inhibited when cells were subjected to continuous biophysical strain, as compared to control at both time points. High strain induced a stronger inhibition of these molecules as compared to strain of Low magnitude. In conclusion, continuous biophysical strain seems to downregulate the expression of the IGF system and may, therefore, reduce the potential of fibrocartilage for growth and repair.  相似文献   
55.
Two-component systems are widely distributed in prokaryotes where they control gene expression in response to diverse stimuli. To study the role of the sixteen putative two-component systems of Listeria monocytogenes systematically, in frame deletions were introduced into 15 out of the 16 response regulator genes and the resulting mutants were characterized. With one exception the deletion of the individual response regulator genes has only minor effects on in vitro and in vivo growth of the bacteria. The mutant carrying a deletion in the ortholog of the Bacillus subtilis response regulator gene degU showed a clearly reduced virulence in mice, indicating that DegU is involved in the regulation of virulence-associated genes.  相似文献   
56.
We used an enzyme-linked immunosorbent assay (ELISA) of immunoglobulin G avidity to determine the dengue immune status of 105 pairs of serum samples from patients infected with dengue virus. This study shows that a simple avidity test, for which only one acute-phase serum sample is required, is potentially more useful than the hemagglutination inhibition test for the discrimination of primary from secondary dengue virus infection, whatever the type of dengue antigen used.  相似文献   
57.
BACKGROUND: Many male cancer survivors experience fertility problems due to antineoplastic treatment. We report the fertility outcome in 67 couples referred to assisted reproduction treatment (ART) because of male factor infertility due to cancer. METHODS: This was a retrospective study assessing the following parameters: diagnosis, cancer treatment, type of fertility treatment and type of sperm used, number of pregnancies and pregnancy outcome. RESULTS: Testicular cancer and lymphomas were the most prevalent diagnoses. Adjuvant treatment with chemo- and/or radiation therapy had been given to 90% of the men. Semen was cryopreserved in 82% of the men prior to treatment. Following antineoplastic treatment, 43% of the men had motile spermatozoa in the ejaculate, but 57% were azoospermic. A total of 151 ART cycles were performed [55 intra-uterine insemination (IUI), 82 ICSI and 14 ICSI-frozen embryo replacement (FER)]. The clinical pregnancy rate per cycle was 14.8% after IUI, 38.6% after ICSI and 25% after ICSI-FER. The corresponding delivery rates were 11.1, 30.5 and 21%. Cryopreserved semen was used in 58% of the pregnancies. The delivery rate per cycle was similar after use of fresh or cryopreserved spermatozoa. CONCLUSIONS: Male cancer survivors have a good chance of fathering a child by using either fresh ejaculated sperm or cryopreserved sperm.  相似文献   
58.
59.
BACKGROUND: Increased total serum IgE levels are a common characteristic of atopic disorders. Six potentially functional variants, including C-590T in the IL4 gene, C-1055T and Arg130Gln in the IL13 gene, and Ile50Val, Ser478Pro, and Gln551Arg in the IL4RA gene, have been evaluated for their involvement in the control of total serum IgE levels and related atopic disorders, but the results of these studies have been inconsistent. OBJECTIVE: We examined whether these 6 variants had genotypic effects on total serum IgE levels in 823 unrelated German children from a large infant cohort, the German Multicenter Atopy Study. METHODS: Marginal effect models were used for the analyses of the repeated IgE measurements. Weighted linear regression and family-based tests of association were performed to minimize the possibility of spurious effects caused by selection bias or confounding on the basis of ethnic background. RESULTS: There are significant associations between increased total serum IgE levels and 2 variants in the IL13 gene (P <.005 and.0002 for Arg130Gln and C-1055T, respectively). These genetic effects are unlikely to be due to solely linkage disequilibrium between 2 polymorphisms, population stratification, or nonrepresentative samples. In addition, exposure to maternal smoking appears to modify the above effects on total serum IgE levels. However, no statistical association was observed between this quantitative phenotype and the other 4 variants examined. CONCLUSION: These findings suggest that variants C-1055T and Arg130Gln of the IL13 gene might play an important role on total serum IgE production in this study population.  相似文献   
60.
The requirement for interleukin-2 (IL-2) in repertoire selection and peripheral activation of CD8 T cells was tested in mice rendered IL-2 deficient by gene targeting and expressing a transgenic T cell receptor (TcR) (F5) specific for influenza nucleoprotein (NP) 366-374 + H-2Db. Positive selection of the transgenic F5 TcR into the CD8 compartment proceeded normally. Both in vivo and in vitro, the antigenic peptide induced depletion of immature thymocytes and proliferation of mature CD8 T cells regardless of the presence of an intact IL-2 gene. In contrast, cytotoxic T lymphocyte (CTL) activity was only generated by T cells from IL-2+ F5 transgenic mice. Exogenous IL-2 was able to fully restore the CTL response of IL-2?/? responder cells in vitro. Thus, both in vivo and in vitro, clonal expansion of CD8 T cells can proceed in the absence of IL-2, whereas in peptide-immunized F5 transgenic mice, induction of cytotoxic effector function is IL-2 dependent.  相似文献   
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