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111.
Azefack Leon Tapondjou Ngninzeko Fernande Ngounou David Lontsi Beibam Lucas Sondengam Marie-Therese Martin Bernard Bodo 《Phytochemistry》1995,40(6):1761-1764
From the methylated trunk wood extracts of Myrianthus liberecus, six pentacyclic triterpenes have been isolated as their methyl esters. These included the known methyl benthamate, methyl euscaphate, methyl tormentate, methyl arjunolate, methyl 3-isoarjunolate and methyl 3β-O-(4″-O-methyl-E-coumaroyl)-arjunolate, a new triterpene derivative. 相似文献
112.
Bodo Kurz Brita von Gaudecker Brigitte Krisch Rolf Mentlein 《Cell and tissue research》1996,283(2):221-229
A new method for the long-term culture of pure rat thymic epithelial cells was established. The cultures were characterized
by immunocytochemistry, electron microscopy and proliferation assays. Non-epithelial thymic cells were eliminated with a reliable
and reproducible pre-plating method, by differential trypsin treatment of the cultures and by addition of horse serum to the
culture medium instead of fetal calf serum. The final cultures contained more than 95% pure epithelial cells as evidenced
by immunostaining for cytokeratin. Ultrastructural studies indicated that these cells are physiologically active epithelial
cells with tonofilaments, desmosomes and filopods. The subsets of the thymic epithelial cells in vitro were investigated by
comparing their staining pattern with that obtained in situ using several subtype-selective antibodies. Thymic epithelial
cells in vitro showed a preferential expression of subcapsular/perivascular and medullary markers. Only few cultivated cells
were of cortical origin. In the first to the fourth subcultures, some cells were immunopositive for the thymus hormone/factor
thymulin. The proliferation of thymic epithelial cells was stimulated by horse serum and to a lesser extend by fetal calf
serum. The adenylate cyclase activators isoproterenol and forskolin, and the glucocorticoid cortisol inhibited the proliferation.
Received: 12 May 1995 / Accepted: 13 October 1995 相似文献
113.
The effects of check dams and other erosion control structures on the restoration of Andean bofedal ecosystems 下载免费PDF全文
Restoring degraded lands in rural environments that are heavily managed to meet subsistence needs is a challenge due to high rates of disturbance and resource extraction. This study investigates the efficacy of erosion control structures (ECSs) as restoration tools in the context of a watershed rehabilitation and wet meadow (bofedal) restoration program in the Bolivian Andes. In an effort to enhance water security and increase grazing stability, Aymara indigenous communities built over 15,000 check dams, 9,100 terraces, 5,300 infiltration ditches, and 35 pasture improvement trials. Communities built ECSs at different rates, and we compared vegetation change in the highest restoration management intensity, lowest restoration management intensity, and nonproject control communities. We used line transects to measure changes in vegetation cover and standing water in gullies with check dams and without check dams, and related these ground measurements to a time series (1986–2009) of normalized difference vegetation index derived from Landsat TM5 images. Evidence suggests that check dams increase bofedal vegetation and standing water at a local scale, and lead to increased greenness at a basin scale when combined with other ECSs. Watershed rehabilitation enhances ecosystem services significant to local communities (grazing stability, water security), which creates important synergies when conducting land restoration in rural development settings. 相似文献
114.
Enhanced Efficiency and Stability of Perovskite Solar Cells Through Nd‐Doping of Mesostructured TiO2 下载免费PDF全文
Bart Roose Karl C. Gödel Sandeep Pathak Aditya Sadhanala Juan Pablo Correa Baena Bodo D. Wilts Henry J. Snaith Ulrich Wiesner Michael Grätzel Ullrich Steiner Antonio Abate 《Liver Transplantation》2016,6(2)
Block‐copolymer templated chemical solution deposition is used to prepare mesoporous Nd‐doped TiO2 electrodes for perovskite‐based solar cells. X‐ray diffraction and photothermal deflection spectroscopy show substitutional incorporation into the TiO2 crystal lattice for low Nd concentration, and increasing interstitial doping for higher concentrations. Substitutional Nd‐doping leads to an increase in stability and performance of perovskite solar cells by eliminating defects and thus increasing electron transport and reducing charge recombination in the mesoporous TiO2. The optimized doping concentration of 0.3% Nd enables the preparation of perovskite solar cells with stabilized power conversion efficiency of >18%. 相似文献
115.
Interaction of trichorzianines A and B with model membranes and with the amoeba Dictyostelium 总被引:4,自引:0,他引:4
M el Hajji S Rebuffat T Le Doan G Klein M Satre B Bodo 《Biochimica et biophysica acta》1989,978(1):97-104
Trichorzianines A (TA) and B (TB) are microheterogeneous mixtures of antibiotic nonadecapeptides of the peptaibol class which interact with lipidic membranes and modify their permeability properties. The TB differ from the TA by replacement of the Gln-18 by a Glu, giving rise to a C-terminal negative charge at neutral pH. The role of this charge on the trichorzianine-lipid interaction was investigated with model membranes by fluorescence spectroscopy and the results were correlated with the biological activity toward the amoeba Dictyostelium discoideum. The interaction of the acidic trichorzianine TB IIIc (Glu-18) with phospholipid bilayers and the subsequent induced permeability were weaker than that exhibited by the uncharged TA IIIc (Gln-18) and MeTB IIIc (TB IIIc monomethyl ester). The unfavourable effect of the negative charge in TB IIIc was strongly enhanced by incorporation of cholesterol in the bilayer. Similarly, TA IIIc as well as MeTB IIIc induced growth inhibition and lysis of the amoeba Dictyostelium at four times lower concentrations than TB IIIc. The results suggested that the interaction of trichorzianines with the phospholipid bilayer and the subsequent modifications of permeability were involved in the inhibitory properties and cell lysis induced by trichorzianines toward Dictyostelium. 相似文献
116.
The structures of two new aliphatic acids, isomuronic and neuropogolic acid, from the lichen Neuropogon trachycarpus, were established by spectroscopic (MS, 1H and 13C NMR) and chemical evidence. Circular dichroism data allowed the configuration of isomuronic acid to be assigned as 2R. 相似文献
117.
The localization and distribution of some cytoskeletal protein components were studied by immunostaining methods in normal and ostosclerotic osteoblast-like cells. The protein components investigated were microtubules (beta-tubulin), intermediate filaments (vimentin), microfilaments (actin and myosin) and structural proteins (alpha-actinin and fibronectin). Although the mechanism is not yet clear, the alterations observed in the pathological cells could well play a role in the expression of otosclerosis. 相似文献
118.
Double immunodiffusion were used as screening test for the diagnosis of paracoccidioidomycosis. Five hundred hospitalized adults from general (150 patients — group I) and from a specialized chest disease hospital (350 patients — group II), were tested. All of them were without definitive etiological diagnosis and clinical specimens were obtained from the patients with positive serology. Testing sera obtained from 150 patients of the group I, fifty six cases of paracoccidioidomycosis were diagnosed. Specimens for mycological examination were subsequently obtained from 50 of these patients; P. brasiliensis could be recovered in 49 (98%). Fundamental importance was the finding of 17 (4.8%) cases of paracoccidioidomycosis among the 350 patients referred from a chest disease hospital (group II). Serological evidence of paracoccidioidomycosis found in 73 (14.6%) of the 500 screened patients, indicates a relatively high prevalence of this mycosis in adults patients admitted to several hospitals in RJ. These data probably do not reflect the real prevalence of paracoccidioidomycosis in RJ and should be considered as a gross underestimation. Thus, attention should also be paid to juvenile forms and DID could be of a great value in screening these cases too.This work forms part of the thesis A importância das técnicas de imunoprecipitação na triagem e diagnóstico da paracoccidioidomicose, histoplasmose e aspergilose. Estudo em população hospitalar do RJ. M. Phil. on Parasite Biology, Instituto Oswaldo Cruz, RJ — 1984. 相似文献
119.
Bodo Scheiper Hans Matter Henning Steinhagen Ulrich Stilz Zsolt Böcskei Valérie Fleury Gary McCort 《Bioorganic & medicinal chemistry letters》2010,20(21):6268-6272
Selective inhibition of the aspartyl protease renin has gained attraction as an interesting approach to control hypertension and associated cardiovascular risk factors given its unique position in the renin–angiotensin system. Using a combination of high-throughput screening, parallel synthesis, X-ray crystallography and structure-based design, we identified and optimized a novel series of potent and non-chiral indole-3-carboxamides with remarkable potency for renin. The most potent compound 5k displays an IC50 value of 2 nM. 相似文献
120.
The everted rat intestinal‐sac model was utilized to assess the effect of post‐prandial conditions on the stereoselective intestinal metabolism of halofantrine to its active metabolite desbutylhalofantrine. Everted intestinal sacs were incubated with (±)‐halofantrine HCl in the presence of simulated bile solution (containing lecithin, lipase and cholesterol) and lipids to mimic post‐prandial conditions in the small intestine. The halofantrine enantiomer concentrations in intestinal sacs were relatively constant in the presence of bile, but decreased significantly on addition of lipids to the incubation media. Formation of desbutylhalofantrine enantiomers was inversely proportional to bile concentration whereas addition of lipids in the presence of bile caused a significant decrease in desbutylhalofantrine:halofantrine ratio of (?) enantiomers. Pre‐treatment of rats with peanut oil had no significant effect on desbutylhalofantrine formation in the incubated sacs or microsomal preparations, nor did it affect the expression of intestinal cytochrome P450. Addition of extra cholesterol to the bile incubations caused a significant increase in tissue halofantrine and desbutylhalofantrine concentrations, which as for lower cholesterol, were diminished on addition of other lipids. The results were consistent with previous in vivo evaluations showing that the desbutylhalofantrine to halofantrine ratio was decreased by the ingestion of a high fat meal. Chirality, 2010. © 2009 Wiley‐Liss, Inc. 相似文献