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Harshad S. Ugamraj Kevin Dang Laure-Hlne Ouisse Benjamin Buelow Eduardo N. Chini Giulia Castello James Allison Starlynn C Clarke Laura M. Davison Roland Buelow Rong Deng Suhasini Iyer Ute Schellenberger Sankar N. Manika Shipra Bijpuria Astrid Musnier Anne Poupon Maria Cristina Cuturi Wim van Schooten Pranjali Dalvi 《MABS-AUSTIN》2022,14(1)
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Comparison of vascular smooth muscle cells from adult human,monkey and rabbit in primary culture and in subculture 总被引:27,自引:0,他引:27
Julie H. Chamley Gordon R. Campbell Janet D. McConnell Prof. Dr. rer. nat. Ute Gröschel-Stewart 《Cell and tissue research》1977,177(4):503-522
Summary A method is presented for growing large numbers of pure isolated smooth muscle cells from adult human, monkey, and rabbit blood vessels in primary culture.In the first few days in culture these cells closely resembled those in vivo and could be induced to contract with angiotensin II, noradrenaline and mechanical stimulation. They stained intensely with antibodies against smooth muscle actin and myosin. Fibroblasts and endothelial cells did not stain with these antibodies thereby allowing the purity of each batch of cultures to be monitored. This was consistently found to be better than 99%. The smooth muscle cells modified or dedifferentiated after about 9 days in culture to morphologically resemble fibroblasts. At this stage cells could no longer be induced to contract and did not stain with the myosin antibodies. Intense proliferation of these cells soon resulted in a confluent monolayer being formed at which stage some differentiated characteristics returned. The modification or dedifferentiation process could be inhibited by the presence of a feeder layer of fibroblasts or endothelial cells, or the addition of cAMP to the culture medium.Smooth muscle cells which had migrated from explants in primary culture, and cells in subculture, had morphological and functional properties of dedifferentiated cells at all times.The advantages of differentiated rather than dedifferentiated smooth muscle cells in culture for the study of mitogenic agents in atherosclerosis is discussed.The authors wish to thank Professor H.H. Bentall of the Royal Postgraduate Medical School, Hammersmith Hospital, London, for making available human material, and Dr. S. Zeki of Department of Anatomy, University College London for material from monkeys. We are also extremely grateful to Professor G. Burnstock for the use of his laboratory facilitiesHolder of a John Halliday Travelling Fellowship from the Life Insurance Medical Research Fund of Australia and New ZealandResearch Fellow with the National Heart Foundation of AustraliaSupported by the Deutsche Forschungsgemeinschaft 相似文献
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A complete 2 x 3 two factorial design was applied to investigate the effects of Fusarium-infected wheat (2.5 mg DON/kg, 0, 25 and 50% of the diets), feed processing (mash and pellets) and the interactions thereof on fattening pigs (96, n= 16/group). Feed-to-gain ratio was significantly increased by contaminated wheat (2.65; 2.62 and 2.73 kg/kg for diets containing 0, 25 and 50% Fusarium-infected wheat, respectively) while digestibility of nutrients and metabolizable energy were not affected by the wheat batch. The feed processing also resulted in significant differences in feed-to-gain ratio but was accompanied by significant effects on the digestibility of organic matter and crude fat and on the metabolizable energy. Clinical chemical parameters were not significantly altered by the inclusion of the infected wheat. The lymphocyte proliferation capacity was not significantly affected by any of the experimental factors. A contribution of the feed processing to the variation of the deoxynivalenol (DON) effect may not be deduced from the present results. 相似文献
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Ivy leaves extracts are authorised in medicinal products for the treatment of acute bronchitis. Different studies and the long experience on the market show safety and efficacy of this drug. A double-blind, randomised study was conducted to assess the efficacy and tolerability of ivy leaves soft extract with an other ivy leaves extract. 590 patients with acute bronchitis participated in this study. They were treated with test or comparator for 7 days (±1). The Bronchitis Severity Score (BSS) decreased gradually and to a similar extent from Day 1 to Day 7 in both treatment groups. Starting from values of 6.2-6.3 ± 1.2, the BSS decreased by approximately 4.7-4.9 points until Day 7, so that patients left the study with a mean BSS of 1.4-1.6. The BSS subscales cough, sputum, rhales/rhonchi, chest pain during coughing, and dyspnoea improved to a similar extent in both treatment groups. Overall, 2.7% of patients (per group and overall) experienced an adverse event, all of which were non-serious. Fewer patients younger than ten years had adverse events than would have been expected from their share of the study population (p = 0.015; Fisher's exact test). As a conclusion, the test product with ivy leaves soft extract proved to be non-inferior to the comparator ivy leaves extract in improving symptoms of acute bronchitis. 相似文献
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On the mechanism of cerebral accumulation of cholestanol in patients with cerebrotendinous xanthomatosis 总被引:1,自引:0,他引:1
Panzenboeck U Andersson U Hansson M Sattler W Meaney S Björkhem I 《Journal of lipid research》2007,48(5):1167-1174
The most serious consequence of sterol 27-hydroxylase deficiency in humans [cerebrotendinous xanthomatosis (CTX)] is the development of cholestanol-containing brain xanthomas. The cholestanol in the brain may be derived from the circulation or from 7alpha-hydroxylated intermediates in bile acid synthesis, present at 50- to 250-fold increased levels in plasma. Here, we demonstrate a transfer of 7alpha-hydroxy-4-cholesten-3-one across cultured porcine brain endothelial cells (a model for the blood-brain barrier) that is approximately 100-fold more efficient than the transfer of cholestanol. Furthermore, there was an efficient conversion of 7alpha-hydroxy-4-cholesten-3-one to cholestanol in cultured neuronal and glial cells as well as in monocyte-derived macrophages of human origin. It is concluded that the continuous intracellular production of cholestanol from a bile acid precursor capable of rapidly passing biomembranes, including the blood-brain barrier, is likely to be of major importance for the accumulation of cholestanol in patients with CTX. Such a mechanism also fits well with the observation that treatment with chenodeoxycholic acid, which normalizes the level of the bile acid precursor, results in a reduction of cholestanol-containing xanthomas even in the brain. 相似文献
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Schlossmacher U Wiens M Schröder HC Wang X Jochum KP Müller WE 《The FEBS journal》2011,278(7):1145-1155
Silicateins are unique enzymes of sponges (phylum Porifera) that template and catalyze the polymerization of nanoscale silicate to siliceous skeletal elements. These multifunctional spicules are often elaborately shaped, with complex symmetries. They carry an axial proteinaceous filament, consisting of silicatein and the scaffold protein silintaphin-1, which guides silica deposition and subsequent spicular morphogenesis. In vivo, the synthesis of the axial filament very likely proceeds in three steps: (a) assembly of silicatein monomers to form one pentamer; (b) assembly of pentamers to form fractal-like structures; and finally (c) assembly of fractal-like structures to form filaments. The present study was aimed at exploring the effect of self-assembled complexes of silicatein and silintaphin-1 on biosilica synthesis in vitro. Hence, in a comparative approach, recombinant silicatein and recombinant silintaphin-1 were used at different stoichiometric ratios to form axial filaments and to synthesize biosilica. Whereas recombinant silicatein-α reaggregates to randomly organized structures, coincubation of silicatein-α and silintaphin-1 (molecular ratio 4 : 1) resulted in synthetic filaments via fractal-like patterned self-assemblies, as observed by electron microscopy. Concurrently, owing to the concerted action of both proteins, the enzymatic activity of silicatein-α strongly increased by 5.3-fold (with the substrate tetraethyl orthosilicate), leading to significantly enhanced synthesis of biosilica. These results indicate that silicatein-α-mediated biosilicification depends on the concomitant presence of silicatein-α and silintaphin-1. Accordingly, silintaphin-1 might not only enhance the enzymatic activity of silicatein-α, but also accelerate the nonenzymatic polycondensation of the silica product before releasing the fully synthesized biosiliceous polymer. 相似文献
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We conducted a comprehensive metabolic phenotyping of potato (Solanum tuberosum L. cv Desiree) tuber tissue that had been modified either by transgenesis or exposure to different environmental conditions using a recently developed gas chromatography-mass spectrometry profiling protocol. Applying this technique, we were able to identify and quantify the major constituent metabolites of the potato tuber within a single chromatographic run. The plant systems that we selected to profile were tuber discs incubated in varying concentrations of fructose, sucrose, and mannitol and transgenic plants impaired in their starch biosynthesis. The resultant profiles were then compared, first at the level of individual metabolites and then using the statistical tools hierarchical cluster analysis and principal component analysis. These tools allowed us to assign clusters to the individual plant systems and to determine relative distances between these clusters; furthermore, analyzing the loadings of these analyses enabled identification of the most important metabolites in the definition of these clusters. The metabolic profiles of the sugar-fed discs were dramatically different from the wild-type steady-state values. When these profiles were compared with one another and also with those we assessed in previous studies, however, we were able to evaluate potential phenocopies. These comparisons highlight the importance of such an approach in the functional and qualitative assessment of diverse systems to gain insights into important mediators of metabolism. 相似文献