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21.

Purpose

In the diagnosis of head and neck melanoma, lymphatic drainage is complex and highly variable. As regional lymph node metastasis is one of the most important prognostic factors, lymphoscintigraphy can help map individual drainage patterns. The aim of this study was to compare the results of lymphoscintigraphy and sentinel lymph node (SLN) detection with theoretical anatomical patterns of lymphatic drainage based on the location of the primary tumour lesion in patients with head and neck melanoma. We also determined the percentage of discrepancies between our lymphoscintigraphy and the theoretical location of nodal drainage predicted by a large lymphoscintigraphic database, in order to explain recurrence and false-negative SLN biopsies.

Methods

In this retrospective study of 152 patients with head and neck melanoma, the locations of the SLNs on lymphoscintigraphy and detected intraoperatively were compared with the lymphatic drainage predicted by on-line software based on a large melanoma database.

Results

All patients showed lymphatic drainage and in all patients at least one SLN was identified by lymphoscintigraphy. Of the 152 patients, 4 had a primary lesion in areas that were not described in the Sydney Melanoma Unit database, so agreement could only be evaluated in 148 patients. Agreement between lymphoscintigraphic findings and the theoretical lymphatic drainage predicted by the software was completely concordant in 119 of the 148 patients (80.4 %, 95 % CI 73.3 – 86 %). However, this concordance was partial (some concordant nodes and others not) in 18 patients (12.2 %, 95 % CI 7.8 – 18.4 %). Discordance was complete in 11 patients (7.4 %, 95 % CI 4.2 – 12.8 %).

Conclusion

In melanoma of the head and neck there is a high correlation between lymphatic drainage found by lymphoscintigraphy and the predicted drainage pattern and basins provided by a large reference database. Due to unpredictable drainage, preoperative lymphoscintigraphy is essential to accurately detect the SLNs in head and neck melanoma.
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ObjectiveThe objective was to develop and operate a cloud-based federated system for managing, analyzing, and sharing patient data for research purposes, while allowing each resource sharing patient data to operate their component based upon their own governance rules. The federated system is called the Biomedical Research Hub (BRH).Materials and MethodsThe BRH is a cloud-based federated system built over a core set of software services called framework services. BRH framework services include authentication and authorization, services for generating and assessing findable, accessible, interoperable, and reusable (FAIR) data, and services for importing and exporting bulk clinical data. The BRH includes data resources providing data operated by different entities and workspaces that can access and analyze data from one or more of the data resources in the BRH.ResultsThe BRH contains multiple data commons that in aggregate provide access to over 6 PB of research data from over 400 000 research participants.Discussion and conclusionWith the growing acceptance of using public cloud computing platforms for biomedical research, and the growing use of opaque persistent digital identifiers for datasets, data objects, and other entities, there is now a foundation for systems that federate data from multiple independently operated data resources that expose FAIR application programming interfaces, each using a separate data model. Applications can be built that access data from one or more of the data resources.  相似文献   
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Catecholamines present in the mammalian ovary are involved in many normal aspects of ovarian functions, including initial follicle growth, steroidogenesis, and pathological states such as polycystic ovary syndrome. Sympathetic nerve fibers are the largest source of norepinephrine (NE), but not the only one. Surgical denervation of the rat ovary reduces, but does not eliminate, the ovarian content of NE. The aim of this work was to explore which intraovarian cells may participate in the ovarian NE homeostasis and the mechanisms involved. It was found that denervated rat ovaries can take up NE and cocaine considerably, decreased its uptake, suggesting involvement of catecholamine transporters. Granulosa cells of rat ovarian follicles present dopamine transporter and NE transporter. Their functionality was confirmed in isolated rat granulosa cells while cocaine blocked the uptake of NE. Furthermore, the presence of the vesicular monoamine transporter 2, together with the exocytotic protein (synaptosome-associated protein of 25 kDa) in granulosa cells, implies catecholamine storage and regulated release. Regulated calcium-dependent release of NE was shown after depolarization by potassium, implying all neuron-like cellular machinery in granulosa cells. These results in rats may be of relevance for the human ovary because dopamine transporter, NE transporter, vesicular monoamine transporter 2, and synaptosome-associated protein of 25-kDa protein and mRNA are found in human ovarian follicles and/or isolated granulosa cells. Thus, ovarian nonneuronal granulosa cells, after taking up catecholamines, can serve as an intraovarian catecholamine-storing compartment, releasing them in a regulated way. This suggests a more complex involvement of catecholamines in ovarian functions as is currently being recognized.  相似文献   
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