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311.
Vladimír Kren Anna Fiserová Lenka Weignerová Ivan Stibor Petr Halada Vera Prikrylová Petr Sedmera Miloslav Pospísil 《Bioorganic & medicinal chemistry》2002,10(2):415-424
Dimers of agroclavine (1) and terguride (2), as well as a series of terguride oligomers, for example trimers (5, 6), tetramer (7), hexamer (8) and functionalized tergurides for further complex clustering were synthesized. Terguride oligomers were screened for their direct cellular toxicity on lymphoma cell lines in vitro and for their immunomodulating activities, represented by the natural killer (NK) cell-mediated cytotoxicity, as the most sensitive screening marker during immune responses. Dimers linked via aromatic spacer showed a high toxicity (1 microM) to lymphoma cells, which was not detected in other derivatives. In vitro and ex vivo experiments performed on mouse spleen lymphocytes in the presence of terguride oligomers demonstrated an immunosuppressive effect of dimers with aromatic spacer (4c-d) and NK cell stimulatory effect of terguride hexamer (8) and trimer with aliphatic spacer (5c). There is a considerable evidence that indolic part of molecule contributes to immunosuppressive action of terguride, which is potentiated in dimers carrying aromatic linker. This effect can be reversed by higher oligomerization of the respective alkaloids. 相似文献
312.
M Kverka Z Ulcova-Gallova J Bartova J Cibulka K Bibkova Z Micanova H Tlaskalova-Hogenova 《PloS one》2012,7(8):e44172
Background and Aims
Anti-sperm antibodies in can markedly reduce the likelihood of natural conception. The etiology of this anti-sperm immunity in human females is unknown. We compared the cytokine response of peripheral blood mononuclear cells (PBMCs) from infertile patients with or without anti-sperm antibodies (ASA) and fertile women.Methodology/Principal Findings
We cultivated the PBMCs together with sperm antigens (whole cells or cell lysate), and screened the supernatants for 40 cytokines by antibody array. When stimulated with whole sperm cells, the PBMCs from patients with ASA produce less IL-3, IL-11, IL-13, ICAM-1, GCSF and more IL-2, IL-4 and IL-12p70 as compared to healthy women. PBMCs from patients with ASA produce typically less IL-13, IL-7, IL-17 and MIG, and more MIP-1β and IL-8, as compared to PBMCs from patients without ASA. In response to sperm cell lysate, PBMCs from infertile women without ASA respond initially by increase in production of growth factors (GCSF, GM-CSF and PDGF-BB) followed by increase in chemokines (e.g. IL-8, MCP-1 and MIP-1β).Conclusions
Cellular immune responses to sperm antigens, measured by production of cytokines, differ among infertile women with ASA, infertile women without ASA and healthy women. This difference could play an important role in the initial steps of the infertility pathogenesis. 相似文献313.
Stanislav Pavelka Arnošt Babický Miloslav Vobecký Jaroslav Lener 《Biological trace element research》2001,82(1-3):133-142
The effect of a high bromide intake on the kinetics of iodide uptake and elimination in the thyroid and skin of adult male
rats was studied. In rats fed a diet with sufficient iodine supply (>25 μg I/d), the iodide accumulation in the skin predominated
during the first hours after 131I -iodide application. From this organ, radioiodide was gradually transferred into the thyroid. A high bromide intake (>150
mg Br−/d) in these animals led to a marked decrease in iodide accumulation, especially by the thyroid, because of an increase in
iodide elimination both from the thyroid and from the skin. In rats kept under the conditions of iodine deficiency (<1 μ I/d),
the iodide accumulation in the thyroid, but not in the skin, was markedly increased as a result of a thyrotropic stimulation.
The effect of a high bromide intake (>100 mg Br−/d) in these animals was particularly pronounced because the rates of iodide elimination were most accelerated both from their
thyroid and from their skin.
Presented in part at the 20th Workshop on Macro and Trace Elements held in Jena (Germany) on December 1–2, 2000. 相似文献
314.
Miloslav Kovanda 《Folia Geobotanica》1970,5(2):171-208
A survey is given of three natural groups of the subsectionHeterophylla (Witas.)Fed. of the genusCampanula L. Within theSaxicolae four taxa of higher rank have been revealed:c. xylocarpa Kovanda (2n=34),C. gentilis Kovanda (2n=34),C. moravica (Spitzner)Kovanda subsp.moravica (2n=68), andC. moravica subsp.xylorrhiza (O. Schwarz)Kovanda (2n=102). BothAlpicolae andLanceolatae are represented by a single species: the first byC. cochleariifolia Lam. (2n=34), the latter byC. serrata (Kit. ap.Schult.)Hendrych (2n=34). Cytology, ecology and geographical distribution of all these taxa have been reviewed, and relationships to the other members of the complex discussed. Infraspecific variation within each species has also been examined. 相似文献
315.
316.
Abstract Cell suspensions of Methanobacterium thermoautotrophicum took up 45 Ca2+ in a temperature-dependent, Ca2+ -saturable and Co2+ -sensitive process. The accumulation of 45 Ca2+ was lower in the cells energized by CO2 + H2 than in those under non-energized conditions. The accumulated Ca2+ were, in part, released by the divalent cations ionophore A23187 in the presence of EGTA while the uptake of Ca2+ was accelerated by the addition of A23187 to the medium containing Ca2+ . The results indicate the presence of a carrier-mediated Ca2+ uptake in the Methanobacterium thermoautotrophicum membrane which is compensated by an energy-dependent and outward-directed Ca2+ transport. 相似文献
317.
Aloisie Poulí
kov Petr Haler Miloslav Kitner 《International Review of Hydrobiology》2004,89(3):278-288
Changes in abundance, biovolume and morphology of Planktothrix agardhii in a natural population were followed over one year period in shallow fishpond Bílá Lhota (Central Moravia, Czech Republic). The selected environmental parameters (pH, oxygen, temperature, conductivity, nutrients, light) were measured at the surface and at the bottom of the fishpond, together with the Planktothrix abundances and filament morphology – filament length, width, shape, aerotopes (gas vacuoles) formation. The annual cycle of P. agardhii in this hypertrophic fishpond starts in March with the germination of hormogonia and the growth of overwintered filaments. The filament length quickly increases to a maximum length in April. The following summer period can be characterized by filament shortening and by changes in the aerotopes shape. On the other hand the abundance and biomass of P. agardhii is increasing until the maximum in August. Further shortening of filaments, loss of aerotopes and hormogoniae formation is typical for the autumn (October) with the average temperature of 9.4 °C. The population overwinters near the pond bottom in the form of hormogonia (60%) and filaments (40%). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
318.
319.
The long-term residual efficacy of 16 pesticides to the predatory phytoseiid mite,Typhlodromus pyri Scheuten, inhabiting commercial sprayed vineyards in South Moravia, Czchoslovakia, was evaluated in laboratory bioassays. Omethoate, chlorpyrifos-methyl and esfenvalerate were assessed as harmful and should not be sprayed. Mancozeb-efosite-Al mixture, diazinon, dicofol, bromopropylate, azinphos-ethyl and phosmet were assessed as moderately harmful. Fenitrothion, phosalone and mancozeb were assessed as slightly harmful and some of them had delayed detrimental effect on the predatory mites. These pesticides can be used only cautiously in IPM programs. Sulphur, penconazole, trimorfamid and endosulfan were assessed as harmless and can be recommended for vineyards withT. pyri. 相似文献
320.
Valigurová A Jirků M Koudela B Gelnar M Modrý D Slapeta J 《International journal for parasitology》2008,38(8-9):913-922
The ultrastructure of two gastric cryptosporidia, Cryptosporidium muris from experimentally infected rodents (Mastomys natalensis) and Cryptosporidium sp. 'toad' from naturally infected toads (Duttaphrynus melanostictus), was studied using electron microscopy. Observations presented herein allowed us to map ultrastructural aspects of the cryptosporidian invasion process and the origin of a parasitophorous sac. Invading parasites attach to the host cell, followed by gradual envelopment, with the host's cell membrane folds, eventually forming the parasitophorous sac. Cryptosporidian developmental stages remain epicellular during the entire life cycle. The parasite development is illustrated in detail using high resolution field emission scanning electron microscopy. This provides a new insight into the ultrastructural detail of host-parasite interactions and species-specific differences manifested in frequency of detachment of the parasitophorous sac, radial folds of the parasitophorous sac and stem-formation of the parasitised host cell. 相似文献