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291.
Florian Schwarz Martina Jennewein Monika Bubel Joerg H. Holstein Tim Pohlemann Martin Oberringer 《Molecular biology reports》2013,40(2):1721-1733
Due to an increasing life expectancy in western countries, chronic wound treatment will be an emerging challenge in the next decades. Because therapies are improving slowly appropriate diagnostic tools enabling the early prediction of the healing success remain to be developed. We used a well-established in vitro assay in combination with the analysis of 27 cytokines to discriminate between fibroblasts from chronic (n = 6) and well healing (n = 8) human wounds. Proliferation and migration of the cells as well as their response to hypoxia and their behaviour in co-culture with microvascular endothelial cells were analyzed. Myofibroblast differentiation, a time-limited essential process of regular wound healing, was also quantified. Besides weaker proliferation and migration significantly higher rates of myofibroblasts were detected in chronic wounds. With respect to the cytokine release, there was a clear trend within the group of chronic wound fibroblasts, which were releasing interferon-γ, monocyte chemotactic protein-1, granulocyte–macrophage colony stimulating factor and basic fibroblast growth factor in higher amounts than fibroblasts from healing wounds. Although the overall response of both groups of fibroblasts to hypoxia and to the contact with endothelial cells was similar, especially chronic wound fibroblasts seemed to benefit from the endothelial interaction during hypoxia and displayed better migration characteristics. The study shows (1) that the assay can identify specific features of fibroblasts derived from different human wounds and (2) that wound fibroblasts are varying in their response to the chosen parameters. Thus, current therapeutic approaches and individual healing prediction might benefit from this assay. 相似文献
292.
Joerg Jores Anne Fischer Pascal Sirand-Pugnet Andreas Thomann Elisabeth M. Liebler-Tenorio Christiane Schnee Ivette Santana-Cruz Martin Heller Joachim Frey 《Systematic and applied microbiology》2013
Five Mycoplasma strains from wild Caprinae were analyzed: four from Alpine ibex (Capra ibex) which died at the Berlin Zoo between 1993 and 1994, one from a Rocky Mountain goat collected in the USA prior to 1987. These five strains represented a population different from the populations belonging to the ‘Mycoplasma mycoides cluster’ as tested using multi locus sequence typing, Matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis and DNA–DNA hybridization. Analysis of the 16S rRNA gene (rrs), genomic sequence based in silico as well as laboratory DNA–DNA hybridization, and the analysis of phenotypic traits in particular their exceptionally rapid growth all confirmed that they do not belong to any Mycoplasma species described to date. We therefore suggest these strains represent a novel species, for which we propose the name Mycoplasma feriruminatoris sp. nov. The type strain is G5847T (= DSM 26019T = NCTC 1362T). 相似文献
293.
Michael Pohlscheidt Melanie Jacobs Stefan Wolf Joerg Thiele Alexander Jockwer Josef Gabelsberger Marco Jenzsch Hermann Tebbe Josef Burg 《Biotechnology progress》2013,29(1):222-229
Increasing capacity utilization and lowering manufacturing costs are critical for pharmaceutical companies to improve their competitiveness in a challenging environment. Development of next generation cell lines, improved media formulations, application of mature technologies and innovative operational strategies have been deployed to improve yields and capacity utilization. This article describes a large‐scale perfusion strategy for the N‐1 seed train bioreactor that was successfully applied to achieve higher inoculation cell densities in the production culture. The N‐1 perfusion at 3,000‐L scale, utilizing a inclined settler, achieved cell densities of up to 158 × 105 cell mL?1 at perfusion rates of 2950 L day?1 and a retention efficiency of >85%. This approach increased inoculation cell densities and decreased cultivation times by ~20% in a CHO‐based, fed‐batch antibody manufacturing process while providing comparable culture performance, productivity, and product quality. The strategy therefore yielded significant increase in capacity utilization and concomitant cost improvement in a large scale cGMP facility. Details of the strategy, the cell retention device, and the cell culture performance are described in this article. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013 相似文献
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295.
Gernot Schilcher Axel Schlagenhauf Daniel Schneditz Hubert Scharnagl Werner Ribitsch Robert Krause Alexander R. Rosenkranz Tatjana Stojakovic Joerg H. Horina 《PloS one》2013,8(12)
Objective
The ethanol lock technique has shown great potential to eradicate organisms in biofilms and to treat or prevent central venous catheter related infections. Following instillation of ethanol lock solution, however, the inherent density gradient between blood and ethanol causes gravity induced seepage of ethanol out of the catheter and blood influx into the catheter. Plasma proteins so are exposed to highly concentrated ethanol, which is a classic agent for protein precipitation. We aimed to investigate the precipitating effect of ethanol locks on plasma proteins as a possible cause for reported catheter occlusions.Methods
Plasma samples were exposed in-vitro to ethanol (concentrations ranging from 7 to 70 v/v%) and heparin lock solutions. In catheter studies designed to mimic different in-vivo situations, the catheter tip was placed in a plasma reservoir and the material contained within the catheter was analyzed after ethanol lock instillation. The samples underwent standardized investigation for protein precipitation.Results
Protein precipitation was observed in plasma samples containing ethanol solutions above a concentration of 28%, as well as in material retrieved from vertically positioned femoral catheters and jugular (subclavian) catheters simulating recumbent or head down tilt body positions. Precipitates could not be re-dissolved by dilution with plasma, urokinase or alteplase. Plasma samples containing heparin lock solutions showed no signs of precipitation.Conclusions
Our in-vitro results demonstrate that ethanol locks may be associated with plasma protein precipitation in central venous catheters. This phenomenon could be related to occlusion of vascular access devices locked with ethanol, as has been reported. Concerns should be raised regarding possible complications upon injection or spontaneous gravity induced leakage of such irreversibly precipitated protein particles into the systemic circulation. We suggest limiting the maximum advisable concentration of ethanol to 28 v/v% in catheter lock solutions. 相似文献296.
Wolf S Haase-Kohn C Lenk J Hoppmann S Bergmann R Steinbach J Pietzsch J 《Amino acids》2011,41(4):809-820
Data concerning the pathophysiological role of extracellular S100A4, a member of the multigenic family of Ca2+-modulated S100 proteins, and its interaction with the receptor for advanced glycation endproducts (RAGE) or other putative
receptors in tumorigenesis, metastasis, and inflammatory processes in vivo are scarce. One reason is the shortage of suitable
radiotracer methods. We report a novel methodology using recombinant human S100A4 as potential probe for molecular imaging
and functional characterization of this interaction. Therefore, human S100A4 was cloned as GST fusion protein in the bacterial
expression vector pGEX-6P-1 and expressed in E. coli strain BL21. Purified recombinant human S100A4 was radiolabeled with the positron emitter fluorine-18 (18F) by conjugation with N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB). The radioligand [18F]fluorobenzoyl-S100A4 (18F-S100A4) was used in cell binding experiments in RAGE-bearing human melanoma cells and endothelial cells in vitro, and in
both biodistribution experiments and small animal positron emission tomography (PET) studies in normal rats in vivo. The cellular
association and tissue-specific distribution of 18F-S100A4 in vitro and in vivo correlated well with the protein expression and anatomical localization of RAGE, e.g., in the
vascular system and in lung. Compared to other S100 RAGE radioligands, the overall findings of this study indicate that extracellular
S100A4 in vivo shows only a moderate interaction with RAGE and, furthermore, exhibits a substantially faster metabolic degradation.
On the other hand, the approach allows the use of quantitative small animal PET and provides a novel probe to both delineate
functional expression and differentiate multiligand interaction of RAGE under normal and pathophysiological conditions in
rodent models of disease. 相似文献
297.
Sheng Zuo Ramakrishna Yadala Fen Yang Paul Talbert Joerg Fuchs Veit Schubert Ulkar Ahmadli Twan Rutten Ales Pecinka Martin A Lysak Inna Lermontova 《Molecular biology and evolution》2022,39(6)
KINETOCHORE NULL2 (KNL2) plays key role in the recognition of centromeres and new CENH3 deposition. To gain insight into the origin and diversification of the KNL2 gene, we reconstructed its evolutionary history in the plant kingdom. Our results indicate that the KNL2 gene in plants underwent three independent ancient duplications in ferns, grasses, and eudicots. Additionally, we demonstrated that previously unclassified KNL2 genes could be divided into two clades αKNL2 and βKNL2 in eudicots and γKNL2 and δKNL2 in grasses, respectively. KNL2s of all clades encode the conserved SANTA domain, but only the αKNL2 and γKNL2 groups additionally encode the CENPC-k motif. In the more numerous eudicot sequences, signatures of positive selection were found in both αKNL2 and βKNL2 clades, suggesting recent or ongoing adaptation. The confirmed centromeric localization of βKNL2 and mutant analysis suggests that it participates in loading of new CENH3, similarly to αKNL2. A high rate of seed abortion was found in heterozygous βknl2 plants and the germinated homozygous mutants did not develop beyond the seedling stage. Taken together, our study provides a new understanding of the evolutionary diversification of the plant kinetochore assembly gene KNL2, and suggests that the plant-specific duplicated KNL2 genes are involved in centromere and/or kinetochore assembly for preserving genome stability. 相似文献
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300.
Loeffler B Heeren J Blaeser M Radner H Kayser D Aydin B Merkel M 《Journal of lipid research》2007,48(2):288-298
LPL mediates the uptake of lipoproteins into different cell types independent of its catalytic activity. The mechanism of this process and its physiological relevance are not clear. Taking into account the importance of the endothelial barrier for lipoprotein uptake, in vitro studies with primary aortic endothelial cells from wild-type and low density lipoprotein receptor (LDLR)-deficient (LDLR(-/-)) mice were performed. Addition of LPL almost doubled the uptake of LDL into wild-type cells. However, there was virtually no LPL-mediated change of LDL uptake into LDLR(-/-) cells. Upregulation of LDLR by lipoprotein-deficient serum/lovastatin in wild-type cells resulted in a 7-fold increase of LPL-mediated LDL uptake. Uptake of chylomicron remnants was not affected by LDLR expression. In proteoglycan-deficient cells, LPL did not increase the uptake of lipoproteins. The physiological relevance of this pathway was studied in mice that were both LDLR(-/-) and transgenic for catalytically inactive LPL in muscle. In the presence of LDLR, inactive LPL reduced LDL cholesterol significantly (13-24%). In the absence of LDLR, LDL cholesterol was not affected by transgenic LPL. Metabolic studies showed that in the presence of LDLR, LPL increased the muscular uptake of LDL by 77%. In the absence of LDLR, transgenic LPL did not augment LDL uptake. Chylomicron uptake was not affected by the LDLR genotype. We conclude that LPL-mediated cellular uptake of LDL, but not of chylomicrons, is dependent on the presence of both LDLR and proteoglycans. 相似文献