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111.
Jan W. Robering Annika Weigand Romy Pfuhlmann Raymund E. Horch Justus P. Beier Anja M. Boos 《Journal of cellular and molecular medicine》2018,22(8):3740-3750
Lymphatic metastasis is one of the main prognostic factors concerning long‐term survival of cancer patients. In this regard, the molecular mechanisms of lymphangiogenesis are still rarely explored. Also, the interactions between stem cells and lymphatic endothelial cells (LEC) in humans have not been well examined. Therefore, the main objective of this study was to assess the interactions between mesenchymal stem cells (MSC) and LEC using in vitro angiogenesis assays. Juvenile LEC were stimulated with VEGF‐C, bFGF, MSC‐conditioned medium (MSC‐CM) or by co‐culture with MSC. LEC proliferation was assessed using a MTT assay. Migration of the cells was determined with a wound healing assay and a transmigration assay. To measure the formation of lymphatic sprouts, LEC spheroids were embedded in collagen or fibrin gels. The LEC's capacity to form capillary‐like structures was assessed by a tube formation assay on Matrigel®. The proliferation, migration and tube formation of LEC could be significantly enhanced by MSC‐CM and by co‐culture with MSC. The effect of stimulation with MSC‐CM was stronger compared to stimulation with the growth factors VEGF‐C and bFGF in proliferation and transmigration assays. Sprouting was stimulated by VEGF‐C, bFGF and by MSC‐CM. With this study, we demonstrate the potent stimulating effect of the MSC secretome on proliferation, migration and tube formation of LEC. This indicates an important role of MSC in lymphangiogenesis in pathological as well as physiological processes. 相似文献
112.
Romy Kandzia Rudolf Grimm Christoph Eckerskorn Peter Lindemann Martin Luckner 《Planta》1998,204(3):383-389
Lanatoside 15′-O-acetylesterase (LAE) from in-vitro-cultivated cells of Digitalis lanata Ehrh. was isolated and partially sequenced. The enzyme was extracted with citrate buffer from acetone dry powder. It was
purified in a two-step chromatographical procedure including Phenyl Sepharose hydrophobic interaction chromatography followed
by CM Sepharose cation-exchange chromatography to more than 330 μmol · s−1 · (g protein)−1. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purified protein showed a major band at 39 kDa.
The protein was identified by correlation of band intensity on SDS-PAGE and enzyme activity of CM Sepharose column fractions.
Size-exclusion chromatography on Sephacryl 200 revealed a single activity peak with an apparent molecular mass of about 85 kDa.
Electrophoresis under nondenaturating conditions of purified LAE showed only one band with esterase activity. The intensity
of this band was correlated with that of the 39-kDa band after SDS-PAGE. About 30% of the protein, including the N-terminus
and several fragments obtained by Lys-C protease digestion, was sequenced. A fragment obtained by Lys-C digestion showed partial
homology to other hydrolases and apoplasmic proteins. It included the probable location of an active-site histidine. The activity
of LAE was high in non-morphogenic D. lanata cell strains selected for high activities in the chemical transformation of cardenolides, but rather low in the proembryogenic
masses of the embryogenic cell strain VIII. It increased during the development of somatic embryos. The LAE activity in leaves
of D. lanata plants was in the range 4–24 nmol · s−1 · (g protein)−1.
Received: 25 March 1997 / Accepted: 3 July 1997 相似文献
113.
Kai Ostermann Marion Richter Matthias Zscharnack Romy Rothe Thomas Walther Gerhard R?del 《DNA sequence》2006,17(6):452-457
Two genes coding for proteins with a high degree of sequence similarity to glycerol-3-phosphate dehydrogenases have been isolated from the yeast Pichiajadinii. Fragments of the genes were PCR-amplified with degenerated primers from genomic DNA of P. jadinii. Clones containing the full-length genes PjGPDI and PjGPD2 were isolated by screening genomic libraries. DNA sequencing revealed open reading frames (ORFs) of 1182 bp and 1185 bp for PjGpdlp and PjGpd2p, respectively. In a complementation study PjGPD1 rescued the growth defect of a Saccharomyces cerevisiae Agpdl mutant strain under osmotic stress, while complementation by PjGPD2 is temperature sensitive. The sequences of the PjGPD1 and PjGPD2 ORFs have been submitted to the EMBL Nucleotide Sequence Database under Accession No. AJ632339 and AJ632340, the sequences of the corresponding genomic DNA fragments under Accession No. AJ632341 and AJ635370, respectively. 相似文献
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116.
Maternal plasma n‐3 and n‐6 polyunsaturated fatty acid concentrations during pregnancy and subcutaneous fat mass in infancy
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117.
The human movement repertoire is characterized by the smooth coordination of several body parts, including arm movements and whole body motion. The neural control of this coordination is quite complex because the various body parts have their own kinematic and dynamic properties. Behavioral inferences about the neural solution to the coordination problem could be obtained by examining the emerging phase relationship and its stability. Here, we studied the phase relationships that characterize the coordination of arm-reaching movements with passively-induced whole-body motion. Participants were laterally translated using a vestibular chair that oscillated at a fixed frequency of 0.83 Hz. They were instructed to reach between two targets that were aligned either parallel or orthogonal to the whole body motion. During the first cycles of body motion, a metronome entrained either an in-phase or an anti-phase relationship between hand and body motion, which was released at later cycles to test phase stability. Results suggest that inertial forces play an important role when coordinating reaches with cyclic whole-body motion. For parallel reaches, we found a stable in-phase and an unstable anti-phase relationship. When the latter was imposed, it readily transitioned or drifted back toward an in-phase relationship at cycles without metronomic entrainment. For orthogonal reaches, we did not find a clear difference in stability between in-phase and anti-phase relationships. Computer simulations further show that cost models that minimize energy expenditure (i.e. net torques) or endpoint variance of the reach cannot fully explain the observed coordination patterns. We discuss how predictive control and impedance control processes could be considered important mechanisms underlying the rhythmic coordination of arm reaches and body motion. 相似文献
118.
119.
Peter M. Stewart Mackenzie Walser 《Biochemical and biophysical research communications》1981,100(4):1430-1435
We have reported that rats given 10–20 mmol/kg of propionate develop hyperammomemia in response to amino acid loads. Ethanol in doses of 0.1–5 mmoles/kg attenuates or prevents this hyperammonemia. Liver ATP, glutamate and aspartate levels are unaffected, but the fall in acetyl CoA and secondarily in N-acetylglutamate caused by propionate alone is much reduced. As a result of this effect, mitochondrial carbamoyl phosphate synthetase activity is restored nearly to normal. Thus low-dose ethanol combats this form of hyperammonemia by augmenting hepatic acetyl CoA. 相似文献
120.