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Clemens Aigner Guenther Winkler Peter Jaksch Gernot Seebacher Gyorgy Lang Sharokh Taghavi Wilfried Wisser Walter Klepetko 《European journal of cardio-thoracic surgery》2005,27(5):757-761
OBJECTIVE: Standard lung donor criteria have been established on opinions and individual experiences rather than on existing evidence. Since the scarcity of donor organs is one of the major limitations to lung transplantation, extension of donor lung criteria might considerably increase the donor pool. This study therefore evaluates the outcome, achieved with the use of extended donors versus standard donors and aims to redefine lung donor criteria. METHODS: We performed a retrospective analysis of 98 consecutive primary lung transplantations from 94 donors from 1/2001 to 12/2002. Donors were classified as extended if they fulfilled at least one criteria: age >55 years, PaO(2) at FiO(2)/PEEP 5 <300mmHg, tobacco history >20 pack years, inhalative drug abuse, presence of infiltration on chest X-ray or purulent secretions at bronchoscopy. Recipients were stratified in two groups according to whether they received a 'standard' or 'extended' organ. Postoperative complications, extubation time, ICU and hospital stay and survival were compared. RESULTS: Twenty-three (24.5%) donors were extended. Twenty-six recipients (26.55%) received organs from extended donors. Differences in intubation times (12+/-2 days standard vs. 14+/-5 days extended, P=0.70), ICU stay (16+/-2 days standard vs. 18+/-5 days extended, P=0.74) and hospital stay (38+/-4 days standard vs. 40+/-6 days extended, P=0.71) were not statistically significant. Postoperative bleeding rates were comparable (n=14 standard vs. n=3 extended) as well as bronchial anastomotic complications (n=7 standard vs. n=3 extended). Three months survival was 88.89% in the standard group vs. 92.31% in the extended group. One year survival is comparable as well with 81.94 vs. 84.62%, respectively. CONCLUSIONS: The use of lung donors who fail to meet standard criteria does not impair short and medium term results compared to standard lung donors. The impact on long term development of BOS has yet to be evaluated. The strict application of standard lung donor criteria excludes a considerable number of lungs potentially suitable for transplantation, thus liberalisation of donor criteria might help to overcome donor shortage. 相似文献
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Mansour Mohamadzadeh Anastassia Pavlidou Alexander Enk Jürgen Knop Erwin Rüde Gernot Gradehandt 《European journal of immunology》1994,24(12):3170-3174
The antibody 4F7 was reported to recognize an epitope expressed on dendritic cells (DC) from various tissues. To study the ability of splenic 4F7+ dendritic cells to process antigen for presentation to CD4+ T cells, DC were enriched using a separation procedure avoiding overnight culture which could lead to an altered phenotype. These DC were used as antigen-presenting cells (APC) in stimulation cultures of major histocompatibility complex class II-restricted T cells. It was found that they induce antigen-dependent lymphokine production by T cells and therefore could present exogenous antigens. These processing takes place intracellularly, because fixation abrogates presentation to T cells. Moreover, antigen presentation needs intracellular processing within endo- or lysosomes as chloroquine-treatment prevents T cell activation. Titration of APC numbers revealed that contaminating APC most likely did not account for antigen-specific T cell activation by DC. No evidence was found for release of antigenic peptides or for partial antigen processing possibly done by cell surface located enzymes on DC. In conclusion, these results indicate that freshly enriched DC are able to process antigens similarly to other APC. 相似文献
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Giuliante Felice Viganò Luca De Rose Agostino M. Mirza Darius F. Lapointe Réal Kaiser Gernot Barroso Eduardo Ferrero Alessandro Isoniemi Helena Lopez-Ben Santiago Popescu Irinel Ouellet Jean-Francois Hubert Catherine Regimbeau Jean-Marc Lin Jen-Kou Skipenko Oleg G. Ardito Francesco Adam René 《Annals of surgical oncology》2021,28(13):8198-8208
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to... 相似文献
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Frank Wilhelm Alexa Holtkamp Antje Theurer Jacques Darman jr. Gernot Duncker Lutz Wilhelm 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(10):640-642
BACKGROUND: Although cataract surgery is highly developed today, there are still problems such as secondary cataract. In polishing the posterior capsule lens, epithelial cells often remain, causing secondary cataracts. Additionally, there are the problems of tissue heating and endothelial cell loss during phacoemulsification by ultrasound. This could be another field for improvement of cataract surgery by using the waterjet. METHODS: After removing the cornea of freshly enucleated porcine bulbs, we used the water jet from 4 to 12 bar. The hit angel on the capsule varied between 45 degrees and 90 degrees. RESULTS: Rupture of the posterior capsule occurred at a mean of 8.5 bar using the jet at 45 degrees and a mean of 8.6 bar using the jet at 90 degrees. CONCLUSION: The waterjet pressure should not be over 4 bar during polishing of the posterior capsule. 相似文献
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Anke Goldhahn Thomas Schrom Alexander Berghaus Albrecht Krause Gernot Duncker 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,23(2):494-497
Lid-loading with precious metals, described by Illig in 1958, has become increasingly important. Because of its good functional
and cosmetic results this method is superior to tarsorrhaphy. Furthermore, lid-loading can be combined with additional surgical
techniques to achieve more dynamic lid-closure. In a prospective study we examined the results after lid-loading and discuss
postoperative changes of the cornea. 相似文献
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Christian Scherwitz Gernot Rassner Rainer Martin 《Archives of dermatological research》1978,263(1):47-58
Summary Candida (C.) albicans cells were exposed to 8-Methoxypsoralen (8-MOP) concentrations of 1.0 g/ml and 10.0 g/ml medium and irradiated with 365 nm light. The amount of energy emitted was 4.8 J/cm2. Two divergent types of cell damage occured concerning yeast cell cytoplasm and cell wall. Two hours after exposure cytoplasmic changes involving mitochondria, which showed irregularities in shape, blurred appearance or loss of mitochondrial cristae and outer membrane were seen. The number of vacuoles was increased. The cytoplasm showed large electron transparent areas, the cytoplasmic membrane disappeared in some areas completely. Nucleus and nuclear envelope usually remained intact in early stages. 24h after exposure conspicuous cell wall alterations were observed in addition to cytoplasmic changes. Newly produced cell wall material formed ball-like protrusions or was adherent sickle-shaped to the cell wall. The investigations strongly suggest that the results found after 8-MOP-UVA treatment of C. albicans cells can not be interpreted in the sense of a general cytotoxic effect. Apparently it takes the form of a combination of events involving regressive and progressive alterations. 相似文献
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Anja Ulmer Oleg Schmidt-Kittler J?rg Fischer Ulf Ellwanger Gernot Rassner Gert Riethmüller Gerhard Fierlbeck Christoph A Klein 《Clinical cancer research》2004,10(2):531-537
PURPOSE: The finding of melanoma cells in the peripheral blood, thus far mainly inferred from the PCR-based demonstration of tyrosinase mRNA, has been associated with metastatic melanoma. Neither the malignant nature nor the prognostic significance of circulating cells could be established. To address this question, we analyzed immunomagnetically isolated circulating melanoma cells for chromosomal aberrations and performed a clinical follow-up study of the enrolled patients. EXPERIMENTAL DESIGN: In a prospective study, blood samples were taken from 164 melanoma patients and 50 donors without malignant disease. Circulating melanoma cells were enriched by immunomagnetic cell sorting using a murine monoclonal antibody against the melanoma-associated chondroitin sulfate proteoglycan. To prove the malignant origin of the positive cells and to define their chromosomal aberrations, we analyzed the genomes of 15 individually isolated cells from seven patients by single-cell comparative genomic hybridization (SCOMP). RESULTS: Absolute and relative frequencies of circulating melanoma cells were associated with stage and with the presence or absence of detectable tumor. The detection of two or more cells correlated significantly with a reduced survival of patients with metastatic melanoma. All of the cells that were analyzed by SCOMP displayed multiple chromosomal changes and carried aberrations typical for melanoma. CONCLUSIONS: Immunomagnetic enrichment enables isolation and genomic characterization of circulating melanoma cells. The prognostic impact on survival of metastatic patients apparently reflects the aggressiveness of an ongoing tumor spread. Direct genomic analysis of the enriched and isolated cells will help to clarify the molecular-genetic basis of the establishment of generalized melanoma. 相似文献