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91.
Hellmut Marx 《Journal of molecular medicine (Berlin, Germany)》1941,20(38):958-961
Ohne Zusammenfassung 相似文献
92.
Dr. Hellmut Marx Dr. Wilhelm Mohr 《Naunyn-Schmiedeberg's archives of pharmacology》1927,123(3-4):205-214
Ohne ZusammenfassungMit 3 Kurven. 相似文献
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94.
Development of (17)O NMR approach for fast imaging of cerebral metabolic rate of oxygen in rat brain at high field 总被引:3,自引:0,他引:3
Zhu XH Zhang Y Tian RX Lei H Zhang N Zhang X Merkle H Ugurbil K Chen W 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(20):13194-13199
A comprehensive technique was developed for using three-dimensional (17)O magnetic resonance spectroscopic imaging at 9.4T for rapidly imaging the cerebral metabolic rate of oxygen consumption (CMRO(2)) in the rat brain during a two-min inhalation of (17)O(2). The CMRO(2) value (2.19 +/- 0.14 micromol/g/min, n = 7) was determined in the rat anesthetized with alpha-chloralose by independent and concurrent (17)O NMR measurements of cerebral H(2)17O content, arterial input function, and cerebral perfusion. CMRO(2) values obtained were consistent with the literature results for similar conditions. Our results reveal that, because of its superior sensitivity at ultra-high fields, the (17)O magnetic resonance spectroscopic imaging approach is capable of detecting small dynamic changes of metabolic H(2)17O during a short inhalation of (17)O(2) gas, and ultimately, for imaging CMRO(2) in the small rat brain. This study provides a crucial step toward the goal of developing a robust and noninvasive (17)O NMR approach for imaging CMRO(2) in animal and human brains that can be used for studying the central role of oxidative metabolism in brain function under normal and diseased conditions, as well as for understanding the mechanisms underlying functional MRI. 相似文献
95.
The Tie-2 ligand angiopoietin-2 is stored in and rapidly released upon stimulation from endothelial cell Weibel-Palade bodies 总被引:15,自引:0,他引:15
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Fiedler U Scharpfenecker M Koidl S Hegen A Grunow V Schmidt JM Kriz W Thurston G Augustin HG 《Blood》2004,103(11):4150-4156
The angiopoietins Ang-1 and Ang-2 have been identified as ligands with opposing functions of the receptor tyrosine kinase Tie-2 regulating endothelial cell survival and vascular maturation. Ang-1 acts in a paracrine agonistic manner, whereas Ang-2 appears to act primarily as an autocrine antagonistic regulator. To shed further light on the complexity of autocrine/paracrine agonistic/antagonistic functions of the angiopoietin/Tie-2 system, we have studied Ang-2 synthesis and secretion in different populations of wild-type and retrovirally Ang-2-transduced endothelial cells. Endogenous and overexpressed endothelial cell Ang-2 is expressed in a characteristic granular pattern indicative of a cytoplasmic storage granule. Light and electron microscopic double staining revealed Ang-2 colocalization with von Willebrand factor, identifying Ang-2 as a Weibel-Palade body molecule. Costaining with P-selectin showed that storage of Ang-2 and P-selectin in Weibel-Palade bodies is mutually exclusive. Stored Ang-2 has a long half-life of more than 18 hours and can be secreted within minutes of stimulation (eg, by phorbol 12-myristate 13-acetate [PMA], thrombin, and histamine). Collectively, the identification of Ang-2 as a stored, rapidly available molecule in endothelial cells strongly suggests functions of the angiopoietin/Tie-2 system beyond the established roles during angiogenesis likely to be involved in rapid vascular homeostatic reactions such as inflammation and coagulation. 相似文献
96.
Baider L Andritsch E Uziely B Goldzweig G Ever-Hadani P Hofman G Krenn G Samonigg H 《Critical reviews in oncology/hematology》2003,46(1):5-16
Age-related differences in emotional distress were examined by studying two random samples (N=424) of women diagnosed with early stages of breast cancer in Graz, Austria and Jerusalem, Israel. We found that psychological distress, coping abilities, and different perceptions of illness are attributable to socialization differences of age experience according to young (49 or younger), intermediate (50-64) and old (65 and older) age groups. Patients were interviewed at home to obtain sociodemographic and medical background data. They also completed five standardized instruments (Brief Symptom Inventory, Psychological Adjustment to Illness Scale, Impact of Events Scale, Mental Adjustment to Cancer, and Perceived Family Support). A two-way MANOVA for all the demographic variables yielded significant main group (Graz vs. Jerusalem) effect (P<0.0001), significant main age effect (P<0.0001) and significant interaction (group by age) effect (P<0.001). Examination of the contribution of the age category to the level of the coping variables showed a different pattern in each group. The psychological distress variables revealed that, in the Jerusalem sample, there is a tendency toward decreasing distress levels with age and, in the Graz sample, elevated scores for the intermediate-age group. Age was found to be related to the level of Global Severity Index (GSI) and to the variables correlated to the GSI level. Psychological intervention should be guided to the different age groups. 相似文献
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99.
Jongho Lee Karin Shmueli Masaki Fukunaga Peter van Gelderen Hellmut Merkle Afonso C. Silva Jeff H. Duyn 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(11):5130-5135
Recent advances in high-field (≥7 T) MRI have made it possible to study the fine structure of the human brain at the level of fiber bundles and cortical layers. In particular, techniques aimed at detecting MRI resonance frequency shifts originating from local variation in magnetic susceptibility and other sources have greatly improved the visualization of these structures. A recent theoretical study [He X, Yablonskiy DA (2009) Proc Natl Acad Sci USA 106:13558–13563] suggests that MRI resonance frequency may report not only on tissue composition, but also on microscopic compartmentalization of susceptibility inclusions and their orientation relative to the magnetic field. The proposed sensitivity to tissue structure may greatly expand the information available with conventional MRI techniques. To investigate this possibility, we studied postmortem tissue samples from human corpus callosum with an experimental design that allowed separation of microstructural effects from confounding macrostructural effects. The results show that MRI resonance frequency does depend on microstructural orientation. Furthermore, the spatial distribution of the resonance frequency shift suggests an origin related to anisotropic susceptibility effects rather than microscopic compartmentalization. This anisotropy, which has been shown to depend on molecular ordering, may provide valuable information about tissue molecular structure. 相似文献
100.
Nacak TG Alajati A Leptien K Fulda C Weber H Miki T Czepluch FS Waltenberger J Wieland T Augustin HG Kroll J 《Circulation research》2007,100(8):1155-1163
Sprouting and invasive migration of endothelial cells are important steps of the angiogenic cascade. Vascular endothelial growth factor (VEGF) induces angiogenesis by activating intracellular signal transduction cascades, which regulate endothelial cell morphology and function. BTB-kelch proteins are intracellular proteins that control cellular architecture and cellular functions. The BTB-kelch protein KLEIP has been characterized as an actin-binding protein that interacts with the nucleotide exchange factor ECT2. We report that KLEIP is preferentially expressed in endothelial cells, suggesting that it may play a critical role in controlling the functions of migrating, proliferating, and invading endothelial cells during angiogenesis. KLEIP mRNA level in endothelial cells is strongly regulated by hypoxia which is controlled by hypoxia-inducible factor-1alpha. Functional analysis of KLEIP in endothelial cells revealed that it acts as an essential downstream regulator of VEGF- and basic fibroblast growth factor-induced migration and in-gel sprouting angiogenesis. Yet, it is not involved in controlling VEGF- or basic fibroblast growth factor-mediated proliferative responses. The depletion of KLEIP in endothelial cells blunted the VEGF-induced activation of the monomeric GTPase RhoA but did not alter the VEGF-stimulated activation of extracellular signal-regulated kinase 1/2. Moreover, VEGF induced a physical association of KLEIP with the guanine nucleotide-exchange factor ECT2, the depletion of which also blunted VEGF-induced sprouting. We conclude that the BTB-kelch protein KLEIP is a novel regulator of endothelial function during angiogenesis that controls the VEGF-induced activation of Rho GTPases. 相似文献