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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   
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ObjectiveWe evaluated the long-term results of sigmoid vaginoplasty in women with gynecologic malignancies after radical pelvic surgery, with specific focus on safety and effects of the procedure on patients' sexuality and self image.MethodsThis prospective study included women with gynecologic malignancies who underwent partial or complete colpectomy as part of the cancer treatment. In all cases a pedicled sigmoid loop was used for the neovaginal reconstruction. Systematic clinical examination was performed and validated questionnaires about sexuality (Female Sexual Function Index), quality of life (SF-12) and susceptibility to depression (ADSk-15) were answered by all patients at the earliest 6 months after vaginoplasty.ResultsSeven patients with sigmoid vaginoplasty, recruited between 11/2003 and 02/2008, were evaluated in the present analysis. Mean patients age was 48 ± 8.49 years. Mean neovaginal length was 6.4 cm (range: 2–12 cm). The mean Female Sexual Function Index (FSFI)-score of all patients was 16.6 ± 12.6. In the subset of sexually active patients the mean FSFI-score was 22.5 ± 9.4 higher. Regarding early operative morbidity and complications, sigmoid vaginal reconstruction appears to be a safe procedure, though in a long-term assessment 85% of the patients developed a vaginal stenosis with the need for operative bougienage.ConclusionsThe vaginal reconstruction using a sigmoid loop is a safe and well accepted procedure in patients with gynecologic malignancies. However lower sexuality scores seem to be achieved than in non-cancer patients after equivalent vaginoplasty. Cancer-related physical and psychological comorbidity seem to have negative effects on the overall outcome and patient's satisfaction.  相似文献   
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We report the case of a 68-year-old man who had previously undergone heart transplantation and pelvic irradiation for Hodgkin’s lymphoma and who was under active surveillance for prostate cancer. In response to his increased prostate-specific antigen levels and elevated Gleason score, he was offered robot-assisted laparoscopic prostatectomy.  相似文献   
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In a Wistar rat model, prolonged supplementation of mustard seed (MS) to the diet significantly ameliorates the induction of colorectal carcinomas by 1,2-dimethylhydrazine (DMH). The expression of the splenocyte major histocompatibility complex class I (MHCI) was found significantly enhanced, whereas that of the major histocompatibility complex class II (MHCII) was significantly decreased. Compared to that of control animals, the proportion of spleenic B- and dendritic cells (DC) was amplified in the MS group. The expressions of MHCI, as well as that of MHCII, were increased in DC cells; whereas in B cells, MHCI expression was augmented but that of MHCII moderately decreased. The percentages of CD8+CD28+ and CD4+CD28+ cells were increased in the MS group, while the CD4+CD25+Foxp3+ subset was depressed. Plasma analysis showed that DMH-exposure induced amplified amounts of interleukin (IL)-4, IL-5, IL-10, and transforming growth factor-beta, whereas MS feeding counteracted this effect but enhanced IL-2, IL12p70, IL21, TNF-alpha, and interferon-gamma. In the SW480 colon adenocarcinoma cell-line, the cytotoxicity of spleenic T-cells from MS-fed animals was significantly increased. In the DMH-exposed rats, the expression of perforin in the spleenic T-cells was dramatically decreased, whereas MS abolished this depression. In summary, dietary MS suppresses DMH-induced immuno-imbalance as well as colon carcinogenesis in rats.  相似文献   
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Fish stocks experiencing high fishing mortality show a tendency to mature earlier and at a smaller size, which may have a genetic component and therefore long-lasting economic and biological effects. To date, the economic effects of such ecoevolutionary dynamics have not been empirically investigated. Using 70 y of data, we develop a bioeconomic model for Northeast Arctic cod to compare the economic yield in a model in which life-history traits can vary only through phenotypic plasticity with a model in which, in addition, genetic changes can occur. We find that evolutionary changes toward faster growth and earlier maturation occur consistently even if a stock is optimally managed. However, if a stock is managed optimally, the evolutionary changes actually increase economic yield because faster growth and earlier maturation raise the stock’s productivity. The optimal fishing mortality is almost identical for the evolutionary and nonevolutionary model and substantially lower than what it has been historically. Therefore, the costs of ignoring evolution under optimal management regimes are negligible. However, if fishing mortality is as high as it has been historically, evolutionary changes may result in economic losses, but only if the fishery is selecting for medium-sized individuals. Because evolution facilitates growth, the fish are younger and still immature when they are susceptible to getting caught, which outweighs the increase in productivity due to fish spawning at an earlier age.  相似文献   
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