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51.
52.
Otto C Gasser M Waaga-Gasser AM Rohde AC Lenhard M Jost S Gassel HJ Ulrichs K Timmermann W 《Human immunology》2002,63(10):880-887
It has been extensively documented the role of the indirect pathway of allorecognition in allograft rejection. However, recent data demonstrate that the manipulation of this pathway could be also sufficient to promote prolongation of allograft survival. In the present study we evaluated the effect of preoperative immunization with the WF-specific MHC class II peptides RT1.D2 and RT1.B2 in combination with low-dose CsA from days 0 to 7 (5 mg/kg/day) and from days 8 to 30 (1 mg/kg/day) after WF small bowel transplantation. Seven days before and on the day of transplantation, LEW recipients were immunized with the two WF MHC class II peptides RT1.B2 and RT1.D2. The CsA monotherapy induced an allograft survival of 49.3 +/- 6.1 days. MHC class II peptide immunization had a limited effect on allograft survival for RT1.D2 (47.1 +/- 3.8 days) and induced prolongation of allograft survival for RT1.B2 (73.6 +/- 34.6 days). This effect seems to be based on the absence or silence of RT1.B2-reactive T cells and rejection seems to be correlated with the presence of RT1.B2-specific T cells in the late phase. Therefore, the combination of RT1.B2 with low-dose CsA shifts the immunological response and protects small bowel allograft rejection. 相似文献
53.
Ursula R. Kees Jette Ford Pamela R. Ranford Susanne E. Peroni Jaclyn A. Biegel Annette H. Parmiter Lavinia A. Hallam Michael L. N. Willoughby Dominic Spagnolo 《Genes, chromosomes & cancer》1994,9(2):129-135
We have established two cell lines, PER-452 and PER-453, from an 8-month-old girl with an extensive pineoblastoma. Characterization of these lines revealed that the proto-oncogenes MYC and MYCN were not amplified, but both cell lines showed MYCN expression comparable to a cell line with 200-fold MYCN amplification. Both cell lines contained an i( 17q). These results support the concept that pineoblastomas belong to a larger group of primitive neuroectodermal tumors of the central nervous system. These two cell lines provide a unique opportunity to investigate the molecular genetic mechanisms underlying these neoplasms further. Genes Chrom Cancer 9:129-135 (1994).© 1994 Wiley-Liss, Inc. 相似文献
54.
Alteration of the LRP1B gene region is associated with high grade of urothelial cancer 总被引:6,自引:0,他引:6
Langbein S Szakacs O Wilhelm M Sukosd F Weber S Jauch A Lopez Beltran A Alken P Kälble T Kovacs G 《Laboratory investigation; a journal of technical methods and pathology》2002,82(5):639-643
We have delineated regions of interest at chromosome 2q21.2, 2q36.3, and 2q37.1 by deletion mapping of 114 urothelial cancers (UC). Altogether, 17%, 18%, and 63% of the G1, G2, and G3 tumors displayed loss of heterozygosity at chromosome 2q, respectively, The region at 2q21.2 was narrowed down to the LRP1B gene (NT_005129.6). Hemi- and homozygous deletion at the LRP1B gene region was seen in 31 of 114 UCs. Only 8% of the UCs with G1 and none with G2 tumors showed loss of heterozygosity at the LRP1B gene, whereas 49% of the G3 UCs had allelic loss at this region. RT-PCR analysis of the LRP1B gene showed the lack of expression of several exons in 2 of 9 cases analyzed. Our analysis suggests that the LRP1B gene is a candidate tumor suppressor gene in UCs. 相似文献
55.
Volker Schmidt Susanne Schneider Julian Schlömer Maria-Elisabeth Krautwald-Junghanns Elvira Richter 《Avian pathology》2008,37(6):589-592
The present report describes a case of Mycobacterium tuberculosis infection in an African Grey parrot (Psittacus erithacus erithacus) kept as a pet bird. Diagnosis was confirmed by microbiologic and pathologic results, and indicated a human–avian transmission. Clinical signs included sublingual nodules resulting in anorexia and signs of osteolysis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation without intralesional acid-fast rods. M. tuberculosis was cultured from a pooled sample of sublingual and liver nodules, and was confirmed via polymerase chain reaction. Transmission between men and parrot was proved by spoligotyping pattern analysis. The absence of facial skin lesions and acid-fast rods within the tubercles is contrary to previous publications of tuberculosis in birds. This disease in a common pet bird species is of zoonotic importance, and those parrots with close contact to owners suffering from tuberculosis may serve as a potential reservoir for human infection. 相似文献
56.
Heike Nave Susanne Kuhlmann Georg Brabant Reinhard Pabst 《Experimental and toxicologic pathology》2003,55(1):45-49
Leptin, a potent anorectic, 16-kDa, adipose tissue-derived protein, predominantly acts in hypothalamic nuclei, signaling obesity and modulating ingestive behavior. To reach this brain area, leptin, probably has to cross the blood-brain barrier (BBB). In some cases of obesity, enhanced leptin levels in the blood do not result in anorectic effects, probably due to an altered leptin transport across the BBB. Therefore, we investigated the BBB in lean and diet-induced obese Lewis rats. To obtain information about the presence of microvessels with barrier dysfunction we examined three brain areas (hypothalamus, cortex, hippocampus) using a monoclonal antibody which detects intact microvessels of the BBB (anti-endothelial barrier antigen, anti-EBA). The results showed a significantly reduced EBA staining in the brain sections of the obese animals, except the hippocampus, compared to the control group. In a second step we injected I125-labeled leptin intravenously (i.v.) in permanent i.v.-cannulated, unrestrained Lewis rats (lean and obese). We measured the radioactivity in the cerebrospinal fluid after puncture of the cisterna magna, in the blood and brain tissue 90 min after injection. The leptin content in the cerebrospinal fluid and brain was not reduced in obese compared to lean rats, thus showing a similar transport capacity of the BBB in both experimental groups. Therefore, the results of the in vivo investigations do not indicate an impairment of the BBB in diet-induced obesity, despite the immunohistological findings. Further functional and morphological studies are necessary to evaluate the specific role of other organs and distinct forms of leptin (free and protein-bound) in the pathogenesis of diet-induced obesity. 相似文献
57.
Tieno Germann Maurice K. Gately David S. Schoenhaut Michael Lohoff Frank Mattner Susanne Fischer Shen-Chu Jin Edgar Schmitt Erwin Rüde 《European journal of immunology》1993,23(8):1762-1770
At least two subsets of CD4+ T helper cell lymphocytes termed Th1 and T h, 2 exist in the mouse and probably in humans. They are characterized by the secretion of different lymphokines and by their functional behavior. Dysregulated expansion of one or the other subset may be one reason for the development of certain diseases. Thus, it is of importance to define the signals involved in the differentiation and activation of the two Th cell subsets. It is known and has been confirmed in this report that the cytokine interleukin (IL)-1 acts onTh2 cells but not on Th1 cells. We now report that a previously identified cytokine which was provisionally termed T cell stimulating factor is identical with IL-12 and exhibits a reciprocal behaviour to IL-1. IL-12 has several effects on Th1 cells. It can induce the proliferation of certain Th1 cells in combination with IL-2. Synthesis of interferon (IFN)-γ by Th1 cells can be triggered by IL-2 plus IL-12. In contrast to the IFN-γ production observed after T cell receptor (TcR) CD3 stimulation of Th1 cells with lectin Concanavalin A the IFN-γ production induced by IL-12+IL-2 is insensitive to the immunosuppressive drug cyclosporin A. Furthermore, IL-12 enhances the TcR/CD3-induced synthesis of IFN-γ of several Th1 clones. Finally, IL-12 (+ IL-2) induces homotypic cell aggregation of Th1 clones. This type of cell aggregation depends on the participation of LFA-1 and ICAM-1 molecules. In all activation systems with Th1 cells no effect of IL-1 was demonstrable. In contrast, only IL-1 but not IL-12 served as a co-stimulatory signal for several Th2 cell lines activated via the TcR/CD3 complex. 相似文献
58.
59.
Persistent HBV and HCV infection represent major causes of chronic liver disease with a high risk of progression to liver cirrhosis and hepatocellular carcinoma (HCC). Conventional protein-based vaccines are highly efficacious in preventing HBV infection; whereas in therapeutic settings with chronically infected patients, results have been disappointing. Prophylactic vaccination against HCV infection has not yet been achieved due to many impediments including frequent spontaneous mutations of the virus with escape from immune system control. Using animal models it has been demonstrated that DNA-based immunisation strategies may overcome this problem because of their potential to induce immunity against multiple viral epitopes. DNA-based vaccines mimic the effect of live attenuated viral vaccines, eliciting cell mediated immunity in addition to inducing humoral responses. Efficacy may further be improved by addition of DNA encoding immunomodulatory cytokines and more recently, direct genetic modulation of antigen-presenting cells, such as dendritic cells (DC), has been shown to increase antigen-specific immune responses. This review focuses on immunological aspects of chronic HBV and HCV infection and on the potential of DNA- and DC-based vaccines for the treatment of chronic viral hepatitis. 相似文献
60.
van Eeden S Offerhaus GJ Morsink FH van Rees BP Busch OR van Noesel CJ 《Virchows Archiv : an international journal of pathology》2004,444(6):590-593
Pyogenic granuloma is a lobular capillary hemangioma that mostly occurs on the skin, but it is also encountered on the mucosal surface of the oral cavity. Only a few cases in other parts of the digestive tract have been reported in Japanese patients. In this report, two Caucasian patients are described, who presented with gastrointestinal bleeding due to the presence of a pyogenic granuloma. One was located in the distal esophagus and could be treated with local excision and laser-photocoagulation therapy. The other one was located in the small intestine and was removed by surgical resection. Although extremely rare, pyogenic granuloma as a cause of gastrointestinal bleeding needs consideration. The lesion is benign, presumably reactive and can be adequately treated by excision or laser photocoagulation. Immunohistochemistry and/or polymerase chain reaction for herpesvirus 8 can reliably distinguish pyogenic granuloma from Kaposis sarcoma, an important differential diagnosis. 相似文献