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51.
Comparison of hormonal activity (estrogen,androgen and progestin) of standardized plant extracts for large scale use in hormone replacement therapy 总被引:11,自引:0,他引:11
Beck V Unterrieder E Krenn L Kubelka W Jungbauer A 《The Journal of steroid biochemistry and molecular biology》2003,84(2-3):259-268
Extracts from red clover (Trifolium pratense), soybean (Glycine max.) and black cohosh (Cimicifuga racemosa) are frequently used as alternative compounds for hormone replacement therapy (HRT) to treat menopausal disorders. Fifteen commercially available products made either from red clover, soybean or black cohosh were tested in in vitro assays in this study. The main polycyclic phenolic compounds of soy and red clover products were biochanin A, genistein, daidzein, formononetin, and glycitein. In red clover products glycitein was not abundant. All the compounds showed clear estrogenic activity through estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta) and affinity to progesterone receptor (PR) and androgen receptor (AR), whereas the compounds from black cohosh did not. This was corroborated by synthetic isoflavones such as biochanin A, daidzein, genistein and formononetin. They exerted affinity to PR and AR in the range of 0.39-110 mM. Statistical analysis applying principal component analysis (PCA) revealed that all red clover and soy products are grouped in different clusters. Red clover products showed a higher affinity to AR and PR than soy products, which is explained by the higher amount of isoflavones present. In vitro assays and chemical analysis showed that theoretical estrogenic activity expressed as equivalent E2 concentration is in the same range as recommended for synthetic estrogens. Broader spectrum of action and hypothesized lower side effects by action through ERbeta make them suitable for alternative hormone replacement therapy. 相似文献
52.
Improved methods are described for anatomical investigation of small insects and other arthropods using serial semithin sections. The specimens were dehydrated with acidified 2,2-dimethoxypropane and embedded in ERL 4206 epoxy resin under vacuum. This procedure ensures good resin impregnation of thin, long body compartments and appendages. Furthermore, it produces excellent overall preservation of the specimen and its fragile anatomical structures. This procedure saves time and gives excellent results when sectioning difficult arthropod material. A continuous recording of serial semithin sections is possible when diamond knives are used. 相似文献
53.
Opium samples from Afghanistan were analyzed by HPLC for their content of morphine and three further alkaloids (codeine, thebaine, and papaverine). To our knowledge, this is the largest set of authentic opium samples analyzed in one study until now. The purpose was to assess possible correlations between samples and selected external factors, such as region of origin within Afghanistan, year of harvest, or intra-batch variation. In the investigated samples, a trend towards higher morphine concentrations in opium from the North-Eastern parts of Afghanistan was observed in the period from 2003 to 2005. More than 75% of the samples contained above 10% of morphine, the overall average was 14.4%. 相似文献
54.
Antiviral activity of the zinc ionophores pyrithione and hinokitiol against picornavirus infections 下载免费PDF全文
Krenn BM Gaudernak E Holzer B Lanke K Van Kuppeveld FJ Seipelt J 《Journal of virology》2009,83(1):58-64
We have discovered two metal ion binding compounds, pyrithione (PT) and hinokitiol (HK), that efficiently inhibit human rhinovirus, coxsackievirus, and mengovirus multiplication. Early stages of virus infection are unaffected by these compounds. However, the cleavage of the cellular eukaryotic translation initiation factor eIF4GI by the rhinoviral 2A protease was abolished in the presence of PT and HK. We further show that these compounds inhibit picornavirus replication by interfering with proper processing of the viral polyprotein. In addition, we provide evidence that these structurally unrelated compounds lead to a rapid import of extracellular zinc ions into cells. Imported Zn2+ was found to be localized in punctate structures, as well as in mitochondria. The observed elevated level of zinc ions was reversible when the compounds were removed. As the antiviral activity of these compounds requires the continuous presence of the zinc ionophore PT, HK, or pyrrolidine-dithiocarbamate, the requirement for zinc ions for the antiviral activity is further substantiated. Therefore, an increase in intracellular zinc levels provides the basis for a new antipicornavirus mechanism. 相似文献
55.
Human monoclonal rheumatoid synovial B lymphocyte hybridoma with a new disease-related specificity for cartilage oligomeric matrix protein 总被引:2,自引:0,他引:2
Souto-Carneiro MM Burkhardt H Müller EC Hermann R Otto A Kraetsch HG Sack U König A Heinegård D Müller-Hermelink HK Krenn V 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(6):4202-4208
Joint-specific self-Ags are considered to play an important role in the induction of synovial T and B cell expansion in human rheumatoid arthritis (RA). However, the nature of these autoantigens is still enigmatic. In this study a somatically mutated IgG2 lambda B cell hybridoma was established from the synovial membrane of an RA patient and analyzed for its Ag specificity. A heptameric peptide of cartilage oligomeric matrix protein (COMP) could be characterized as the target structure recognized by the human synovial B cell hybridoma. The clonotypic V(H) sequences of the COMP-specific hybridoma could also be detected in synovectomy material derived from five different RA patients but in none of the investigated osteoarthritis cases (n = 5), indicating a preferential usage of V(H) genes closely related to those coding for a COMP-specific Ag receptor in RA synovial B cells. Moreover, the COMP heptamer was preferentially recognized by circulating IgG in RA (n = 22) compared with osteoarthritis patients (n = 24) or age-matched healthy controls (n = 20; both p < 0.0001). Hence, the COMP-specific serum IgG is likely to reflect local immune responses toward a cartilage- and tendon-restricted Ag that might be crucial to the induction of tissue damage in RA. 相似文献
56.
Ali Özmen Sibylle Madlener Sabine Bauer Stanimira Krasteva Caroline Vonach Benedikt Giessrigl Manuela Gridling Katharina Viola Nicole Stark Philipp Saiko Barbara Michel Monika Fritzer-Szekeres Thomas Szekeres Tülay Askin-Celik Liselotte Krenn Georg Krupitza 《Phytomedicine》2010,17(1):55-62
Aim of this studyWithin the genus Scutellaria various species are used in different folk medicines throughout Asia. Traditional Chinese Medicine (TCM) uses S. baicalensis (Labiatae) to treat various inflammatory conditions. The root shows strong anticancer properties in vitro and was suggested for clinical trials against multiple myeloma. Further, S. barbata was successfully tested against metastatic breast cancer in a phase I/II trial. Therefore, we investigated the anti-cancer properties of S. orientalis L. ssp. carica Edmondson, an endemic subspecies from the traditional medicinal plant S. orientalis L. in Turkey, which is used to promote wound healing and to stop haemorrhage.Materials and methodsFreeze-dried plant material was extracted with petroleum ether, dichloromethane, ethyl acetate, and methanol and the bioactivity of these extracts was analysed by proliferation assay, cell death determination, and by investigating protein expression profiles specific for cell cycle arrest and apoptosis.ResultsThe strongest anti-leukemic activity was shown by the methanol extract, which contained apigenin, baicalein, chrysin, luteolin and wogonin, with an IpC50 of 43 μg/ml (corresponding to 1.3 mg/ml of dried plant material) which correlated with cyclin D1- and Cdc25A suppression and p21 induction. At 132 μg/ml (=4 mg/ml of the drug) this extract caused genotoxic stress indicated by substantial phosphorylation of the core histone H2AX (γ-H2AX) followed by activation of caspase 3 and signature-type cleavage of PARP resulting in a 55% apoptosis rate after 48 hours of treatment.ConclusionsHere, we report for the first time that S. orientalis L. ssp. carica Edmondson exhibited potent anti-leukaemic properties likely through the anti-proliferative effect of baicalein and the genotoxic property of wogonin. 相似文献
57.
Morphological fine tuning of the feeding apparatus to proboscis length in Hesperiidae (Lepidoptera) 下载免费PDF全文
The form and function of the hesperiid feeding apparatus was studied in detail. The butterflies in the family Hesperiidae are of particular interest because the longest proboscis ever recorded in Papilionoidea was found in the Neotropical genus Damas. We focused on the functional morphology by comparing proboscis morphology as well as size and composition of both the stipes pump and the cibarial suction pump in skippers with short and extremely long proboscis. Results revealed that all studied Hesperiidae have the same proboscis micromorphology and sensilla endowment regardless of the proboscis length. However, the numbers of internal muscles of the proboscis, the morphology of the stipes pump as well as the pumping organs for nectar uptake are related to the proboscis length. We conclude that the low number of tip sensilla compared to proboscis length is responsible for remarkably longer manipulation times of long‐proboscid species during flower visits. The organs for proboscis movements and nectar uptake organs are well tuned to the respective proboscis length and are accordingly bigger in species with a proboscis that measures twice the body length. 相似文献
58.
The external structures of the proboscis are investigated in eye-frequenting species of Noctuidae, Geometridae and Pyralidae
by means of scanning electron microscopy. They are compared with non-eye-frequenting representatives of these families. In
Noctuidae, highly specialized fruit-piercing, skin-piercing blood-sucking, and sweat-feeding representatives have been included.
All hemi- and eulachryphagous species have a soft proboscis tip which is characterized by few sensilla and strongly elongated,
dentate plates of the dorsal galeal linkage. The latter structures leave broad gaps between them that lead into the food canal
at the tip. This arrangement permits the uptake of fluid suspensions such as lachrymal fluid, wound exudates and pus. The
modified dorsal galeal linkage is regarded as an adaptation for this highly derived feeding habit. The rough surface of the
proboscis is likely to cause irritation and possible mechanical damage to the conjunctiva and cornea which results in an increased
lachrymal flow and production of pus. In contrast to fruit-piercing and skin-piercing Noctuidae, there are no erectile structures
on the proboscis of eye-frequenting species.—The comparison with related non-eye-frequenting species demonstrates that the
particular morphology of the proboscis tip in lachryphagous moths evolved convergently in different families of Leipdoptera. 相似文献
59.
Julia Romanova Brigitte M. Krenn Markus Wolschek Boris Ferko Ekaterina Romanovskaja-Romanko Alexander Morokutti Anna-Polina Shurygina Sabine Nakowitsch Tanja Ruthsatz Bettina Kiefmann Ulrich K?nig Michael Bergmann Monika Sachet Shobana Balasingam Alexander Mann John Oxford Martin Slais Oleg Kiselev Thomas Muster Andrej Egorov 《PloS one》2009,4(6)
Background
We developed a novel intranasal influenza vaccine approach that is based on the construction of replication-deficient vaccine viruses that lack the entire NS1 gene (ΔNS1 virus). We previously showed that these viruses undergo abortive replication in the respiratory tract of animals. The local release of type I interferons and other cytokines and chemokines in the upper respiratory tract may have a “self-adjuvant effect”, in turn increasing vaccine immunogenicity. As a result, ΔNS1 viruses elicit strong B- and T- cell mediated immune responses.Methodology/Principal Findings
We applied this technology to the development of a pandemic H5N1 vaccine candidate. The vaccine virus was constructed by reverse genetics in Vero cells, as a 5∶3 reassortant, encoding four proteins HA, NA, M1, and M2 of the A/Vietnam/1203/04 virus while the remaining genes were derived from IVR-116. The HA cleavage site was modified in a trypsin dependent manner, serving as the second attenuation factor in addition to the deleted NS1 gene. The vaccine candidate was able to grow in the Vero cells that were cultivated in a serum free medium to titers exceeding 8 log10 TCID50/ml. The vaccine virus was replication deficient in interferon competent cells and did not lead to viral shedding in the vaccinated animals. The studies performed in three animal models confirmed the safety and immunogenicity of the vaccine. Intranasal immunization protected ferrets and mice from being infected with influenza H5 viruses of different clades. In a primate model (Macaca mulatta), one dose of vaccine delivered intranasally was sufficient for the induction of antibodies against homologous A/Vietnam/1203/04 and heterologous A/Indonesia/5/05 H5N1 strains.Conclusion/Significance
Our findings show that intranasal immunization with the replication deficient H5N1 ΔNS1 vaccine candidate is sufficient to induce a protective immune response against H5N1 viruses. This approach might be attractive as an alternative to conventional influenza vaccines. Clinical evaluation of ΔNS1 pandemic and seasonal influenza vaccine candidates are currently in progress. 相似文献60.