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51.
Tetracycline-regulated gene expression following direct gene transfer into mouse skeletal muscle 总被引:7,自引:0,他引:7
Jyotsna Dhawan Thomas A. Rando Sarah L. Elson Hermann Bujard Helen M. Blau 《Somatic Cell and Molecular Genetics》1995,21(4):233-240
For most experimental and therapeutic applications of gene transfer, regulation of the timing and level of gene expression is preferable to constitutive gene expression. Among the systems that have been developed for pharmacologically controlled gene expression in mammalian cells, the bacterial tetracycline (tet)-responsive system has the advantage that it is dependent on a drug (tet) that is both highly specific and non-toxic. The tet-responsive system has been previously used to modulate expression of cell cycle regulatory proteins in cultured cells, reporter genes in plants and transgenic mice and reporter genes directly injected into the heart. Here we show that orally or parenterally administered tet regulates expression of tet-responsive plasmids injected directly into mouse skeletal muscle. Reporter gene expression was suppressed by two orders of magnitude in the presence of tet, and that suppression was reversed when tet was withdrawn. These data show that skeletal muscle offers an accessible and well characterized target tissue for tet-controlled expression of genesin vivo, suggesting applications to developmental studies and gene therapy. 相似文献
52.
Hermann A. Hienz Paul N. Ehlers 《Journal of molecular medicine (Berlin, Germany)》1957,35(19):985-985
Ohne Zusammenfassung 相似文献
53.
Hermann Schtzl Gerhard Schwarzfischer Dietlinde Rose Birgit Gathof Wilhelm Weise Friedrich Deinhardt Klaus Von Der Helm 《Journal of medical virology》1994,43(2):159-160
The extent of human T-cell lymphotropic retorvirus HTLV-I and HTLV-II infections in the general population in central Europe has not been investigated fully. Two hundred forty-eight thousand blood donors from southern Germany were examined serologically for antibodies to the human lymphotropic retroviruses HTLV-I and HTLV-II: 0.021% were confirmed postive and 0.056% were “indeterminate”. A limited number of seropositives and “indeterminate” samples were analyzed by polymerase chain reaction (PCR): the seropositives were confirmed as positive and 43% of the “indeterminate” samples were PCR-positive. The range of 0.021% HTLV-positives in 248,000 donors, i.e. about two in 10,000 individuals, mirrors closely the published data for the United States. © 1994 Wiley-Liss, Inc. 相似文献
54.
Quantitative measurement of cortical surface features in localization-related temporal lobe epilepsy 总被引:1,自引:0,他引:1
Oyegbile T Hansen R Magnotta V O'leary D Bell B Seidenberg M Hermann BP 《Neuropsychology》2004,18(4):729-737
Differences in cortical surface features between healthy controls (n = 48) and patients with temporal lobe epilepsy (n = 46), ages 14-59, were characterized by means of advanced quantitative MRI processing techniques. Cortical surface features of interest included gyral and sulcal curvature, cortical depth, and total cortical surface area. Epilepsy patients and controls differed on measures of gyrification; the abnormalities generalized despite the focal nature of the primary epileptic process. Changes in cortical surface features were associated with increasing chronological age in both groups. Abnormalities in gyrification were associated with cognitive performance and with other morphometric measurements (e.g., surface cerebral spinal fluid). These findings are related to the literature regarding morphometric changes associated with temporal lobe epilepsy and normal aging. 相似文献
55.
Glycoprotein B of bovine herpesvirus type 4: Its phylogenetic relationship to gB equivalents of the herpesviruses 总被引:1,自引:0,他引:1
Michael Goltz Hermann Broll Annette Mankertz Wolfgang Weigelt Hanns Ludwig Hans-Jörg Buhk Kerstin Borchers 《Virus genes》1994,9(1):53-59
In order to estimate the phylogenetic relationship of BHV-4 among the herpesviruses, we have cloned and sequenced its glycoprotein B (gB). The 2.6 kb open reading frame codes for a 874 amino acid long protein. The comparison of its deduced amino acid sequence with those of its counterparts in 19 distinct herpesviruses groups BHV-4 into the -herpesvirinae. The calculation of an evolutionary tree emphasized that BHV-4 is more closely related to herpesvirus saimiri (HVS) than to Epstein-Barr virus (EBV). However, in contrast to EBV and HVS, the gB of BHV-4 contains a putative protease cleavage site and 20 potential N-glycosylation sites. The alignment of the amino acid sequences revealed that 10 cysteine and 7 proline residues, as well as the motifs SPF and GQLG, were completely conserved among the 20 investigated gBs. 相似文献
56.
57.
Helicobacter pylori-Specific Immune Responses of Children: Implications for Future Vaccination Strategy
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Günter Bode Isolde Piechotowski Dietrich Rothenbacher Hermann Brenner 《Clinical and Vaccine Immunology : CVI》2002,9(5):1126-1128
We analyzed the specific anti-Helicobacter pylori immunoglobulin G (IgG) antibody profile for a sample of 824 asymptomatic schoolchildren in southern Germany (mean age, 10.7 ± 0.65 years) with an H. pylori-specific IgG enzyme-linked immunosorbent assay and Western blot analysis. The prevalence of infection was 19.8% (95% confidence interval, 17.1 to 22.7%). The immunoresponses were characterized predominantly by antibodies against low-molecular-mass antigens of 14 and 29 kDa, with a significant difference between children of German and Turkish nationalities (P = 0.0012 and P < 0.0001, respectively). 相似文献
58.
Dominique Blanchard Claude Gaillard Patrice Hermann Jacques Banchereau 《European journal of immunology》1994,24(2):330-335
In the present study, we examined the participation of CD40 ligand (L)-CD40 interaction in T cell-dependent B cell responses. To this end, purified B lymphocytes were cultured over irradiated CD4+ cloned T cells activated with immobilized anti-CD3 antibody. The anti-CD40 mAb 89 strongly blocked, in a specific fashion, both proliferation and Ig secretion of tonsil B cells. Interestingly, proliferation of surface (s)IgD+ B cell was significantly less inhibited by anti-CD40 than that of sIgD? cells. Preactivated T cells induced B cells to grow and secrete immunoglobulins preferentially in response to IL-2. This contrasts with the CD40 system where B cells are essentially responsive to IL-4 and IL-10 but not to IL-2 alone. Collectively, these data indicate that CD40L-CD40 interaction plays an important role in IL-2-mediated T cell-dependent B cell responses. However, the activation of a subset of sIgD+ cells may be independent of this interaction. 相似文献
59.
Claudia Müller Hermann Herbst Barbara Uchanska-Ziegler Andreas Ziegler Friedrich Schunter Ingeborg Steiert Claude Muller Peter Wernet 《Human immunology》1985,14(4):333-349
The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6+ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6+ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6. 相似文献
60.
Krug N Hohlfeld JM Geldmacher H Larbig M Heermann R Lavallee N Nguyen DT Petzold U Hermann R 《Allergy》2005,60(3):354-359
BACKGROUND: Loteprednol etabonate (LE) is a novel soft steroid that was designed to improve the benefit/risk ratio of topical corticosteroid therapy. This study assesses the clinical efficacy and safety of three different doses of LE nasal spray in seasonal allergic rhinitis (SAR). METHODS: In this single-center, double-blind, placebo-controlled, parallel-group trial 165 subjects with SAR to grass pollen received daily single doses of either 100, 200, 400 microg LE nasal spray, or placebo for 14 days. The patients underwent three 4-h allergen challenges with grass pollen in an environmental exposure unit at a screening visit (baseline) and on days 7 and 14 of treatment. Standardized nasal symptom scores were obtained every 20 min. Nasal flow, nasal secretions, and FEV(1) were measured every hour during allergen challenges. RESULTS: After 14 days of treatment, patients who received 400 microg LE had significantly lower total nasal symptom scores compared with those receiving placebo (P = 0.007). LE400 reduced rhinorrhea, nasal congestion, nasal itching, the amount of nasal secretions, and improved nasal flow as compared with placebo (P < 0.05). LE100 and LE200 were not significantly different from placebo. All treatments were well tolerated. CONCLUSIONS: Loteprednol 400 microg once daily is superior to placebo and the only effective dose tested in improving nasal symptoms and objective parameters in patients with SAR. 相似文献