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51.
Willenberg HS Haase M Papewalis C Schott M Scherbaum WA Bornstein SR 《Neuroendocrinology》2005,82(5-6):274-281
Corticotropin-releasing hormone (CRH) is not only the principal regulator of the central hypothalamic-pituitary-adrenal (HPA) axis but also exerts direct actions on peripheral tissues. We analyzed the expression of CRH receptors in microdissected preparations of normal human adrenal glands and in adrenocortical and adrenomedullary tumors, employing immunohistochemistry, quantitative RT-PCR of microdissected adrenal tissues, and in situ hybridization. The effect of CRH on adrenal steroidogenesis was tested in adrenal cells. Immunoreactive CRH1R was found primarily within the zona reticularis. In addition, we found a higher expression of CRH type-1 and 2 receptors mRNAs in preparations of adrenal cortices as compared to pheochromocytomas, a 6-fold increase in preparations of clinically unapparent adrenocortical adenomas, and a 10- to 60-fold increase in cortisol-producing adrenal adenomas. Stimulation of the adrenal tumor cell line NCI-H295R with CRH elicited a 1.4-fold increase in DHEA secretion. This result could be reproduced in a culture of primary human adrenocortical cells. We conclude that adrenocortical cells exhibit a higher expression of functional CRH receptors than chromaffin cells and that CRH acts on adrenal DHEA production. The data support the assertion of a direct action of CRH on human adrenocortical cells in addition to an intra-adrenal CRH receptor/adrenocorticotropin system. Enhanced CRH1R expression may be involved in adrenocortical tumorigenesis. 相似文献
52.
Lopman B Vennema H Kohli E Pothier P Sanchez A Negredo A Buesa J Schreier E Reacher M Brown D Gray J Iturriza M Gallimore C Bottiger B Hedlund KO Torvén M von Bonsdorff CH Maunula L Poljsak-Prijatelj M Zimsek J Reuter G Szücs G Melegh B Svennson L van Duijnhoven Y Koopmans M 《Lancet》2004,363(9410):682-688
53.
Miche E Radzewitz A Notohamiprodjo G Baller D Kloppe A Eckert S Gleichmann U 《European journal of heart failure》2002,4(4):431-438
BACKGROUND: The rate constant for global fatty acid influx (k(1)) was studied in 12 male patients with dilated cardiomyopathy (DCM). METHOD: 10 normal subjects served as controls. 201-Thallium (201TI) and [123I]-phenyl-pentadecanoic acid (IPPA) were administered during bicycle exercise under fasting conditions. RESULTS: All patients showed non-homogeneous tracer uptake defects for 201TI and IPPA. k(1) was significantly higher in DCM patients than controls. k(1) showed significant inverse correlation between cardiac index, left-ventricular ejection fraction, left-ventricular enddiastolic pressure and echocardiographic left-ventricular ejection fraction. CONCLUSION: We presume that an increased regional rate constant of IPPA influx into the myocardial tissue in patients with DCM reflects a compensatory mechanism of altered myocardium. 相似文献
54.
Luiz Schweitzer Alexandre Cunha Thiago Pereira Kerstin Mika Ana Maria Botelho do Rego Ana Maria Ferraria Heinz Kieburg Sven Geissler Eckart Uhlmann Janosch Schoon 《Materials》2020,13(23)
Loosening of orthodontic and orthopedic implants is a critical and common clinical problem. To minimize the numbers of revision surgeries due to peri-implant inflammation or insufficient osseointegration, developments of new implant manufacturing strategies are indicated. Ultrafast laser surface texturing is a promising contact-free technology to modify the physicochemical properties of surfaces toward an anti-infectious functionalization. This work aims to texture Ti6Al4V surfaces with ultraviolet (UV) and green (GR) radiation for the manufacturing of laser-induced periodic surface structures (LIPSS). The assessment of these surface modifications addresses key aspects of topography, morphology and chemical composition. Human primary mesenchymal stromal cells (hMSCs) were cultured on laser-textured and polished Ti6Al4V to characterize the surfaces in terms of their in vitro biocompatibility, cytotoxicity, and metal release. The outcomes of the in vitro experiment show the successful culture of hMSCs on textured Ti6Al4V surfaces developed within this work. Cells cultured on LIPSS surfaces were not compromised in terms of their viability if compared to polished surfaces. Yet, the hMSC culture on UV-LIPSS show significantly lower lactate dehydrogenase and titanium release into the supernatant compared to polished. Thus, the presented surface modification can be a promising approach for future applications in orthodontics and orthopedics. 相似文献
55.
Maria Benito de Valle Tobias Müller Einar Björnsson Morgane Otten Martin Volkmann Olaf Guckelberger Bertram Wiedenmann Riadh Sadik Eckart Schott Mats Andersson Thomas Berg Björn Lindkvist 《Digestive and liver disease》2014,46(10):903-908
Background
Elevated IgG4 levels have been reported among patients with primary sclerosing cholangitis. Epidemiological data has only been provided from tertiary centres.Aims
To investigate the prevalence of elevated IgG4 levels and to compare prognosis between patients with and without elevated IgG4 levels in serum in two European cohorts of patients with primary sclerosing cholangitis.Methods
Serum IgG4-levels were measured in a consecutive series of patients from Berlin, and retrospectively collected in a population-based cohort from Sweden (total N = 345). Cox's proportional hazard analysis was used to calculate relative risks for liver-related death or liver transplantation and cholangiocarcinoma.Results
Elevated IgG4 values were demonstrated in 10% of patients. A previous history of pancreatitis, combined intra- and extrahepatic biliary involvement and jaundice were independently associated with elevated IgG4 in multivariate analysis. IgG4 status was not associated with an increased risk for the combined endpoint liver-related death or liver transplantation or cholangiocarcinoma.Conclusion
The prevalence of elevated IgG4 values among European patients with primary sclerosing cholangitis is similar to what previously has been reported from the United States. Elevated IgG4 was not associated with an increased risk of liver transplantation or liver-related death or cholangiocarcinoma. 相似文献56.
57.
Astrid Godron Jér?me Harambat Valérie Boccio Anne Mensire Adrien May Claire Rigothier Lionel Couzi Benoit Barrou Michel Godin Dominique Chauveau Stanislas Faguer Marion Vallet Pierre Cochat Philippe Eckart Geneviève Guest Vincent Guigonis Pascal Houillier Anne Blanchard Xavier Jeunemaitre Rosa Vargas-Poussou 《Clinical journal of the American Society of Nephrology》2012,7(5):801-809
58.
59.
Arne J. Venjakob Stephan Vogt Klaus Stöckl Thomas Tischer Philipp J. Jost Eckart Thein Andreas B. Imhoff Hermann Anetzberger 《Journal of orthopaedic research》2013,31(11):1820-1827
Local cooling is very common after bone and joint surgery. Therefore the knowledge of bone blood flow during local cooling is of substantial interest. Previous studies revealed that hypothermia leads to vasoconstriction followed by decreased blood flow levels. The aim of this study was to characterize if local cooling is capable of inducing reduced blood flow in bone tissue using a stepwise‐reduced temperature protocol in experimental rabbits. To examine bone blood flow we utilized the fluorescent microsphere (FM) method. In New Zealand white rabbits one randomly chosen hind limb was cooled stepwise from 32 to 2°C, whereas the contra lateral hind limb served as control. Injection of microspheres was performed after stabilization of bone and muscle temperature at each temperature level. Bones were removed, dissected and fluorescence intensity was determined to calculate blood flow values. We found that blood flow of all cooled regions decreased relative to the applied external temperature. At maximum cooling blood flow was almost completely disrupted, indicating local cooling as powerful regulatory mechanism for regional bone blood flow (RBBF). Postoperative cooling therefore may lead to strongly decreased bone blood flow values. As a result external cooling has capacity to both diminish bone healing and reduce bleeding complications. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1820–1827, 2013 相似文献
60.
Stephan Vogt Arne J. Venjakob Klaus Stöckl Thomas Tischer Philipp J. Jost Andreas B. Imhoff Eckart Thein Hermann Anetzberger 《Archives of orthopaedic and trauma surgery》2013,133(9):1233-1241