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71.
Wieland Kiess Bernhard Leisner Rainer Haas 《Journal of cancer research and clinical oncology》1985,110(1):85-86
Summary The case of a 41/2-year-old girl with disseminated neuroblastoma and concomitant osteomyelitis is reported. Neuroblastoma was detected in the vertebral column, the right suprarenal fossa, the left side of cranium and in bone marrow aspirates. Osteomyelitis was present in the left femur and was due to Salmonella tennessee. For the first time in the literature the two lesions were demonstrated by means of simultaneous 131I-MIBG and 99mTc-DPD scintigraphy. The diagnoses were proved by direct histological and microbiological studies. 相似文献
72.
Steffi Silling Ulrike Wieland Marko Werner Herbert Pfister Anja Potthoff Alexander Kreuter 《Emerging infectious diseases》2014,20(1):142-145
Human papillomavirus (HPV) XS2 was isolated from warts on an immunosuppressed patient. After HPV vaccination, the warts resolved. HPVXS2 was also found in warts and normal skin of HIV-positive patients and rarely in HIV-negative controls. Further studies should elucidate the mechanisms that lead to wart clearance. 相似文献
73.
Y. Feng Y. Wang Z. Yang L. Wu S. Hoffmann T. Wieland N. Gretz H.-P. Hammes 《Acta diabetologica》2014,51(2):211-218
Vasoregression characterizes diabetic retinopathy in animal models and in humans. We have recently demonstrated that vasoregression is earlier initiated in a rat model of ciliopathy-induced retinal neurodegeneration (TGR rat). The aim was to assess the balance between vasoregressive effects of chronic hyperglycemia and photoreceptor degeneration on adult vascular remodelling. The retinas were analyzed at 4 and 9 months after streptozotocin-induced diabetes. Neurodegeneration was determined by quantitation of cell numbers and retinal layer thickness. Vasoregression was assessed by quantitative retinal morphometry in retinal digest preparations. Retinal VEGF levels were measured by ELISA. Glial activation, expression and location of HSP27 and phosphorylated HSP27 were evaluated by immunofluorescence staining. Unexpectedly, the numbers of acellular capillaries were reduced at both time points and led to fewer intraretinal microvascular abnormalities in late stage diabetic TGR. Concomitantly, inner nuclear layers (INLs) in diabetic TGR rats were protected from cell loss at both time points. Consequently, glial activation was reduced, but VEGF level was increased in diabetic TGR retinas. Expressions of HSP27 were upregulated in glia cells in the preserved INL of diabetic TGR. Chronic hyperglycemia preserves the microvasculature in the retinal model of neurodegeneration. Cell preservation in the retinal INL was associated with protective gene regulation. Together, these data indicate that diabetes can induce vasoprotection, in which retinal glia can play a particular role. 相似文献
74.
75.
Shymanskaya Aliaksandra Worthoff Wieland A. Stoffels Gabriele Lindemeyer Johannes Neumaier Bernd Lohmann Philipp Galldiks Norbert Langen Karl-Josef Shah N. Jon 《Molecular imaging and biology》2020,22(1):198-207
Molecular Imaging and Biology - Positron emission tomography (PET) using O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET) improves the diagnostics of cerebral gliomas compared with conventional... 相似文献
76.
Karin Wieland Mahmoud Masri Jeremy von Poschinger Thomas Brück Christoph Haisch 《RSC advances》2021,11(46):28565
Oil-producing yeast cells are a valuable alternative source for palm oil production and, hence, may be one important piece of the puzzle for a more sustainable future. To achieve a high-quality product, the lipid composition inside oil-producing yeast cells is a crucial parameter for effective process control. Typically, the lipid composition is determined by off-line gas chromatography. A faster, less cumbersome approach is proposed here, by using non-invasive in-line Raman spectroscopy. A fed-batch fermentation of C. oleaginosus – a well-known oleaginous yeast – is used as model experiment to highlight the potential of Raman spectroscopy for in-line lipidomics. The temporal progression of biomass formation, lipid production and glucose consumption are determined based on PLS-regression models allowing process-relevant information on time to be accessed. Additionally, Gaussian curve fitting was applied to extract increasing and decreasing trends of saturated and unsaturated fatty acids produced by C. oleaginosus throughout the fermentation process.Oil-producing yeast cells are a valuable alternative source for palm oil production and, hence, may be one important piece of the puzzle for a more sustainable future. 相似文献
77.
c-fos and c-jun mRNA expression in a pig liver model of ischemia/reperfusion: effect of extended cold storage and the antioxidant idebenone 总被引:6,自引:0,他引:6
OBJECTIVES: Expression of immediate early genes has been reported during reperfusion after ischemia in rat livers due to oxygen radical formation. This study investigates in perfused pig livers the effect of the antioxidant idebenone and of cold ischemia time on the gene expression of c-fos and c-jun. DESIGN AND METHODS: Livers were perfused for 210 min after 0.5 h or 20 h ischemic storage (4 degrees C). One group of pigs was fed idebenone (280 mg/day/7days) prior to organ harvesting. C-fos and c-jun mRNA were determined by RT-PCR at 3, 30, 60, 120 180, 210 min during reperfusion. RESULTS: Lipid peroxidation increased in liver tissue form 0.54 +/- 0.21 to 1. 09 +/- 0.54 nmol MDA/mg protein during reperfusion after 20 h compared to 0.5 h cold storage. This was antagonized by idebenone (0. 68 +/- 0.20 nmol/MDA/mg protein). C-fos and c-jun were strongly induced in livers stored for 20 h, which was attenuated by idebenone (p < 0.05). CONCLUSIONS: These findings suggest that cold ischemia time and oxygen radicals are critical for immediate early gene expression and that application of an effective antioxidant can attenuate this early stress reaction of the pig liver. 相似文献
78.
Monica Patten Jan Bünemann Bryan Thoma Elisabeth Kr?mer Martin Thoenes Sabine Stübe Clemens Mittmann Thomas Wieland 《Cardiovascular research》2002,53(1):156-164
OBJECTIVE: Endotoxin (LPS)-induced acute cardiac failure during sepsis is associated with alterations in G protein mediated signal transduction. We therefore examined the expression of the G proteins G(i), G(q), and G(s) and of four 'regulators of G protein signaling' (RGS) proteins, RGS1, RGS4, RGS5, and RGS16 in rat hearts. METHODS: For in vivo experiments, Wistar rats were treated with 600 microg/day E. coli LPS, intravenously) and hearts were excised after 6, 24 and 72 h. Cultured neonatal rat cardiomyocytes were treated with 4 microg/ml LPS for 24 and 72 h. Isolated membrane proteins were used for Western blot analysis and for evaluation of phospholipase C (PLC) activity. RGS16 mRNA was detected by RNAse protection. RESULTS: LPS induced G(i) protein 1.4-fold 72 h after in vivo administration of LPS, whereas expression of G(s) and G(q) was unaltered. After 6 h of LPS treatment, RGS16 mRNA was transiently up-regulated 3.7-fold, followed by transient protein induction (24 h: 2.5-fold; 72 h: 1.5-fold). Similarly, RGS4 protein was transiently induced (24 h: 3.1-fold; 72 h: 1.5-fold), whereas expression of RGS1 and RGS5 was not altered. Similar to the LPS-treated rat hearts, RGS16 expression was transiently induced by LPS in cultured neonatal rat cardiomyocytes (24 h: 1.6-fold, 72 h: 0.9-fold). To determine the functional consequences of the RGS protein induction phospholipase C (PLC) activity was analyzed in membranes obtained from solvent and LPS-treated hearts. Basal and endothelin-1-stimulated PLC activity was transiently repressed by LPS with a maximum after 24 h although no apparent changes in PLCbeta1 or endothelin receptor expression could be detected. CONCLUSION: These data suggest that the rapid up-regulation of cardiac RGS4 and RGS16 is associated with a desensitization of endothelin-1 receptor signaling. Up-regulation of these RGS proteins may thus be involved in the early onset of cardiac failure during sepsis. 相似文献
79.
Endothelial cell migration and tube formation in response to vascular endothelial growth factor (VEGF) play an important role in the process of angiogenesis. Recent data indicate that angiotensin type 2 (AT2) receptor stimulation is antiangiogenic. Therefore, we studied the effect of angiotensin II (Ang II) on VEGF-induced migration and in vitro tube formation of human endothelial cells. Ang II inhibited VEGF-induced migration of EA.hy926 cells, human coronary artery (HCA) and human dermal microvascular (HDM) endothelial cells (ECs) as well as tube formation by HDMECs. The AT2 receptor antagonist PD123,319 but not the AT1 receptor antagonist losartan blocked the inhibitory effect of Ang II. The inhibitory effect of Ang II on VEGF-induced migration of endothelial cells was mimicked by the specific AT2 receptor agonist CGP-42112A. The phosphorylation of Akt and its downstream effector endothelial NO synthase (eNOS) is pivotal to VEGF-induced angiogenesis. We therefore investigated the effect of Ang II on VEGF-induced Akt and eNOS phosphorylation. Ang II diminished the VEGF-induced phosphorylation of Akt and eNOS in endothelial cells, whereas the autophosphorylation of VEGF receptors was unaffected. CGP-42112A again mimicked and PD123,319 but not losartan blocked the inhibitory effect of Ang II. Treatment of endothelial cells with pertussis toxin (PTX) totally abolished the AT2 receptor-mediated inhibition of VEGF-induced endothelial cell migration and blocked the inhibition of Akt and eNOS phosphorylation. In conclusion, this study indicates that AT2 receptor stimulation inhibits VEGF-induced endothelial cell migration and tube formation via activation of a PTX-sensitive G protein. These findings may explain the reported antiangiogenic properties of the AT2 receptor. 相似文献
80.