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Jan Gessmann Dominik Seybold Elvira Peter Thomas Armin Schildhauer Manfred Köller 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2013,398(1):161-167
Purpose
Freshly prepared autologous plasma clots may serve as a carrier matrix for expanded multipotent mesenchymal stromal cells (MSCs) or bone marrow cells. By varying the calcium concentration, plasma clots with different properties can be produced. The purpose of this in vitro study was to determine the optimal calcium concentrations for the clotting process, intra-clot cell viability, and clot lysis.Methods
Different plasma clots were prepared by adding an equal volume of RPMI1640 (with or without MSCs) to citrate plasma (either containing platelets or platelet-free). Clotting was initiated by the addition of CaCl2 (10 g/100 ml H2O, 10 % solution). The final concentration of CaCl2 ranged from 1 to 10 % by volume of plasma. Viability and distribution of the MSCs were analysed by calcein-AM/propidium iodide staining. MSC-embedded plasma clots were dissolved with trypsin (0.25 %), and recovered cells were further incubated for 1 week under cell culture conditions.Results
The viability of MSCs embedded in clots formed by the addition of 1–8 % by volume CaCl2 was not affected by incubation of up to 1 week. In contrast, clots produced by higher volumes of CaCl2 solutions (9–10 % by volume of plasma) showed decreased numbers of viable cells. Intra-clot cell proliferation was highest in clots produced by addition of 5 % CaCl2 by plasma volume. Osteocalcin release was not influenced in platelet-free plasma but decreased in platelet-containing plasma. Morphological analysis of stained recovered MSCs revealed that lysis of the plasma clot did not affect cell morphology or subsequent spontaneous proliferation.Conclusions
Clot formation and clot stability can be controlled by changing the concentration of CaCl2 added to plasma. The addition of 5 % CaCl2 produced a plasma clot with optimal results for stem cell delivery. 相似文献95.
Dominik Grotegerd Thomas Suslow Jochen Bauer Patricia Ohrmann Volker Arolt Anja Stuhrmann Walter Heindel Harald Kugel Udo Dannlowski 《European archives of psychiatry and clinical neuroscience》2013,263(2):119-131
Bipolar disorders rank among the most debilitating psychiatric diseases. Bipolar depression is often misdiagnosed as unipolar depression, leading to suboptimal therapy and poor outcomes. Discriminating unipolar and bipolar depression at earlier stages of illness could therefore help to facilitate efficient and specific treatment. In the present study, the neurobiological underpinnings of emotion processing were investigated in a sample of unipolar and bipolar depressed patients matched for age, gender, and depression severity by means of fMRI. A pattern-classification approach was employed to discriminate the two samples. The pattern classification yielded up to 90 % accuracy rates discriminating the two groups. According to the feature weights of the multivariate maps, medial prefrontal and orbitofrontal regions contributed to classifications specific to unipolar depression, whereas stronger feature weights in dorsolateral prefrontal areas contribute to classifications as bipolar. Strong feature weights were observed in the amygdala for the negative faces condition, which were specific to unipolar depression, whereas higher amygdala features weights during the positive faces condition were observed, specific to bipolar subjects. Standard univariate fMRI analysis supports an interpretation, where this might be related to a higher responsiveness, by yielding a significant emotion × group interaction within the bilateral amygdala. We conclude that pattern-classification techniques could be a promising tool to classify acutely depressed subjects as unipolar or bipolar. However, since the present approach deals with small sample sizes, it should be considered as a proof-of-concept study. Hence, results have to be confirmed in larger samples preferably of unmedicated subjects. 相似文献
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Philipp G. Smann Juan Eugenio Iglesias Boris Gutman Dominik Grotegerd Ramona Leenings Claas Flint Udo Dannlowski Emily K. Clarke-Rubright Rajendra A. Morey Theo G.M. van Erp Christopher D. Whelan Laura K. M. Han Laura S. van Velzen Bo Cao Jean C. Augustinack Paul M. Thompson Neda Jahanshad Lianne Schmaal 《Human brain mapping》2022,43(1):207-233
Structural hippocampal abnormalities are common in many neurological and psychiatric disorders, and variation in hippocampal measures is related to cognitive performance and other complex phenotypes such as stress sensitivity. Hippocampal subregions are increasingly studied, as automated algorithms have become available for mapping and volume quantification. In the context of the Enhancing Neuro Imaging Genetics through Meta Analysis Consortium, several Disease Working Groups are using the FreeSurfer software to analyze hippocampal subregion (subfield) volumes in patients with neurological and psychiatric conditions along with data from matched controls. In this overview, we explain the algorithm's principles, summarize measurement reliability studies, and demonstrate two additional aspects (subfield autocorrelation and volume/reliability correlation) with illustrative data. We then explain the rationale for a standardized hippocampal subfield segmentation quality control (QC) procedure for improved pipeline harmonization. To guide researchers to make optimal use of the algorithm, we discuss how global size and age effects can be modeled, how QC steps can be incorporated and how subfields may be aggregated into composite volumes. This discussion is based on a synopsis of 162 published neuroimaging studies (01/2013–12/2019) that applied the FreeSurfer hippocampal subfield segmentation in a broad range of domains including cognition and healthy aging, brain development and neurodegeneration, affective disorders, psychosis, stress regulation, neurotoxicity, epilepsy, inflammatory disease, childhood adversity and posttraumatic stress disorder, and candidate and whole genome (epi-)genetics. Finally, we highlight points where FreeSurfer-based hippocampal subfield studies may be optimized. 相似文献
98.
Göschel Michael Treml Benedikt Dahlmann Philipp Warnstorff Dominik 《Notfall & Rettungsmedizin》2022,25(3):207-215
Notfall + Rettungsmedizin - Die O2-Inhalationstherapie gehört zu den Standardmaßnahmen der Notfallmedizin und wird zunehmend kritisch diskutiert. Pathophysiologische Überlegungen und... 相似文献
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