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Frank Josef Mller Oliver Zierau Torsten Hertrampf Anja Bliedtner Patrick Diel Günter Vollmer 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):296-303
Isoflavones (ISOs) are bioactive food ingredients of the traditional East Asian diet and currently discussed as alternatives to classical hormone replacement therapies and for reducing the prevalence of hormone-dependent cancers. Although there are many studies on ISOs, not much is known about their long-term effects.Therefore, we performed an animal experiment analyzing the effects of three different diets: a phytoestrogen-free diet, a diet supplemented with genistein (700 μg/g diet) and an ISO-high diet (232 μg daidzein and 240 μg genistein/g) at two distinct time points, juvenile (21 days) and adult (97 days). Exposure started prior to mating of the parents and throughout the life of the offspring.We observed a stronger increase of uterine wet weights in juvenile offspring with genistein exposure (1018 ± 350 mg/kg BW) than with ISO-high diet (497 ± 133 mg/kg BW). Whereas the expression of proliferation related genes (PCNA; Ki67; IGF-1; IGF-1R), analyzed by real-time-qPCR and Western blot, were significantly down-regulated in juvenile animals exposed to genistein. Additionally, genistein exposure led to estrogenic responses, observed upon increase of complement C3 and decrease of estrogen receptors gene expressions, while the exposure to ISO-high diet did not show these effects.In conclusion, both the time point on which phytoestrogen exposure starts together with the composition of the ingested phytoestrogen containing diet are of great importance for the biological response of the offspring. 相似文献
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Summary Dissociated single cells from chicken retina or tectum kept in rotation-mediated cell culture aggregate, proliferate and establish a certain degree of histotypical cellto-cell relationships (sorting out), but these systems never form highly laminated aggregates (nonstratified R- and T-aggregates). In contrast, a mixture of retinal plus pigment epithelial cells forms highly stratified aggregates (RPE-aggregates, see Vollmer et al. 1984). The present comparative study of stratified and nonstratified aggregates enables us to investigate the process of cell proliferation uncoupled from that of tissue stratification. Here we try to relate these two basic neurogenetic processes with patterns of expression of cholinesterases (AChE, BChE) during formation of both types of aggregates.During early aggregate formation, in both stratified and nonstratified aggregates an increased butyrylcholinesterase activity is observed close to mitotically active cells. Quantitatively both phenomena show their maxima after 2–3 days in culture. In contrast, AChE-expression in all systems increases with incubation time. In nonproliferative areas, in the center of RPE-aggregates, the formation of plexiform layers is characterized initially by weak BChE and then strong AChE-activity. These areas correspond with the inner (IPL) and outer (OPL) plexiform layers of the retina in vivo. Although by sucrose gradient centrifugation we find that the 6S- and the fiber-associated 11S-molecules of AChE are present in all types of aggregates, during the culture period the ratio of 11S/6S-forms increases only in RPE-aggregates, which again indicates the advanced degree of differentiation within these aggregates.It is thus demonstrated that cholinesterases first correlate with neuronal cell proliferation and later with stratification, which indicates functions of both enzymes during both developmental periods.Abbreviations
AChE
acetylcholinesterase
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BChE
butyrylcholinesterase
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iso-OMPA
specific inhibitor of BChE
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BW 284C51
specific inhibitor of AChE
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IPL
inner plexiform layer
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OPL
outer plexiform layer 相似文献
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Paul G. Layer Regina Alber Patrick Mansky Günter Vollmer Elmar Willbold 《Cell and tissue research》1990,259(2):187-198
Summary We report here that similar to E6-chicken retinal cells, dissociated cells from 5.5-day-old (E5.5) quail retinae reaggregate in rotary culture, multiply about tenfold and reestablish histotypical areas. These cellular aggregates include all nuclear layers either with inversed or correct laminar polarity, depending on the local origin of the cells (called rosetted and laminar in-vitro-retinae (IVR), respectively; Layer and Willbold 1989). In combined cultures, chick and quail cells are evenly mixed only during the first two days of culture. Along with the assembly of single cells into rosettes and then into discrete laminae, sectors of chick and quail cells begin to segregate. They are delineated by borders running radially through all three nuclear layers. Thus, interspecies migration of cells at this advanced stage of differentiation is strongly inhibited. Concomitant with this segregation, coherent radial columns spanning all three layers but containing cells from either species only, can be traced histologically. We conclude that a weak segregation of chick and quail retinal cells takes place already at the single cell level, but that the permanent segregation of entire tissue parts must be due to clonal cellular proliferation within the IVR in conjunction with some developmental-structural mechanism retaining clonal progenies within a columnar order.Abbreviations
ECM
extracellular matrix
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E5.5
days of embryonic age
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GCL
ganglion cell layer
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GC's
ganglion cells
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i.c.
in culture
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INL
inner nuclear layer
- rosetted in-vitro-retina
retinal cell organoid aggregated from single cells of the central retina
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IPL
inner plexiform layer
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MRE
marginal retinal epithelium
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ONL
outer nuclear layer
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OPL
outer plexiform layer
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OS
ora serrate
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PR
photoreceptor cell
- laminated in-vitro-retina
fully laminated retinal cellorganoid resembling an E15-retina aggregated from cells of the eye periphery including RPE
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RPE
retinal pigment epithelium 相似文献
7.
Determination was made of the proportion of selected by-products (acetaldehyde, ethyl acetate, methanol, propanol, isobutanol, 2-methyl-butanol, 3-methyl-butanol) of batch and continuous ethanol fermentation carried out with the use of yeastSaccharomyces cerevisiae, strain 0–11, cells immobilized by adsorption on selected carriers (foamed polystyrene, bone shot, beech wood chips, porous glass) as well as by entrapping in calcium alginate and calcium pectinate gel. 相似文献
8.
High Performance Liquid Chromatography of Molecular Species from Free Sterols and Sterylglycosides Isolated from Oat Leaves and Seeds 总被引:1,自引:0,他引:1
Free sterols and sterylglycosides (SG) from oat leaves and seedswere isolated by conventional thin layer chromatography (TLC)and subjected to high performance liquid chromatography (HPLC)for resolution of molecular species. Acylsterylglycosides, isolatedby TLC, were converted to SG by mild alkaline hydrolysis anddetermined as SG. Sterols and SG were injected onto the columnwithout any chemical treatment and the separated species weredetected at 200 nm. The separation of SG-species follows exactlythe separation of free sterols. Though gas liquid chromatography still is the method of choice,advantages of HPLC is to analyse directly the SG-species withouthydrolysis and derivatization as compared to GLC. After TLCthe sterol- and the SG-fraction are injected directly onto thecolumn. This is extremely important for labile sterylglycosidesor sterols, as demonstrated for the avenasterols.
1 Preliminary reports have been presented on the "4. Arbeitstagung,Pflanzliche Lipide", October 78, 1983 in M?nster (FRG)and on the "6th International Symposium on the Structure, Functionand Metabolism of Plant Lipids", Neuchatel, Switzerland, July1620, 1984. (Received November 12, 1984; Accepted January 14, 1985) 相似文献
9.
Zusammenfassung Regionale und artliche Unterschiede der Rückstände von Quecksilber in Eiern von sieben Brutvogelarten der deutschen Nordseeküste wurden untersucht. Bei vier Arten stellten wir deutliche geographische Unterschiede in der Kontamination fest (Abb. 1). Höchstgehalte fanden wir in Eiern von der Elbmündung (Region V). Austernfischer- und Flußseeschwalbeneier von der inneren Deutschen Bucht (Region VI) enthielten größere Mengen als solche von Nordfriesland (Region VII). Der gesetzliche Richtwert für Eier (0,03 mg/kg) wurde von 353 der 355 untersuchten Eier überschritten. Fluß- und Brandseeschwalbe waren am stärksten, Brandgans, Austernfischer und Lachmöwe am wenigsten mit Quecksilber kontaminiert (Abb. 2, 4.2.). Mit Ausnahme von Brandgans und Silbermöwe erreichten die Rückstände in vielen Eiern der anderen Arten, an der Elbe sogar in allen Eiern, eine den Bruterfolg gefährdende Größenordnung, insbesondere bei der Flußseeschwalbe.
Pollutants in eggs of birds breeding at the German North Sea Coast. II. Mercury
Summary Regional and interspecific differences of mercury residues were investigated in the eggs of seven species breeding at the German North Sea Coast (Tadorna tadorna, Haematopus ostralegus, Charadrius hiaticula, Larus argentatus, L. ridibundus, Sterna hirundo, S. sandvicensis). We found distinct geographical differences in contamination (Fig. 1): In eggs from the Elbe Eastuary (region V) maximum residues of mercury were ascertained. Eggs of Oystercatcher and Common Tern from the Bay of Helgoland (region VI) contained larger quantities than eggs from Northern Frisia (region VII). 353 from 355 eggs examined showed a value exceeding the legal standard value for eggs which is 0,03 mg/kg in Germany. Common Tern and Sandwich Tern eggs had the highest, Shelduck, Oystercatcher and Blackheaded Gull eggs the lowest mercury contamination (Fig. 2, 4.2.). With the exception of Shelduck and Herring Gull, residues in many eggs of the other species — at the river Elbe in all eggs — came up to a range endangering breeding success, especially in Common Terns.相似文献
10.
Two Lyt-2 polypeptides arise from a single gene by alternative splicing patterns of mRNA 总被引:17,自引:0,他引:17
The Lyt-2/3 molecule is a glycoprotein expressed on T lymphocytes and has classically been considered a marker for the cytotoxic/suppressor T cell subset. It has been postulated to be a receptor for class I major histocompatibility complex proteins. We have used a cDNA clone encoding the analogous human protein, Leu-2/T8, to isolate mouse cDNA clones, which were used as probes to isolate mouse genomic clones. By transfection we have shown that the mouse homologue of Leu-2/T8 is Lyt-2 and not Lyt-3. We have further demonstrated that two Lyt-2 polypeptide chains are encoded by a single gene and result from alternative modes of mRNA splicing. The nucleotide sequence of cDNA clones encoding each of these polypeptide chains has been determined and shows the difference between the two Lyt-2 polypeptide chains to be in the lengths of their cytoplasmic tails. 相似文献