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Start Over Coverage 3-9

1. A coccidian (Apicomplexa: Eimeriidae) with extracytoplasmally located stages in the kidney tubules of golden carp (Carassius auratus gibelio L.) (Cyprinidae)

Creator:
Lukeš, J.
Format:
print
Type:
model:internalpart and TEXT
Subject:
coccidia, Eimeria, fish, fusion, and host-parasite interaction
Language:
English
Description:
Numerous coccidian stages were found in the kidney tubules of the golden carp (Carassius auratus gibelio). The merogonial and gamogonial stages were localized extracytoplasmally in the microvillous region of the epithelial cells. The host-parasite interface consisted of i) a large area where the parasite was separated from the host cytoplasm by the parasitophorous vacuole membrane only, and ii) a zone of multiple fusions of the host cell membrane investing the parasite to the neighbouring microvilli. The taxonomic status of the extracytoplasmic stages is not clear, however, their possible appurtenance to Eimeria scardimi, which was frequently found in the kidneys of golden carps in the same population, is discussed.
Rights:
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2. A comparative study of the utilization of ether- and ester-linked phospholipid-containing liposomes by J774.E1 macrophage cell-line infected with Leishmania mexicana mexicana amastigotes

Creator:
Hrčková, G., Shah, A., Hart, D.T., and Halton, D.W.
Format:
print
Type:
model:internalpart and TEXT
Subject:
Leishmania m. mexicana, ester-, ether-linked phosphatydilcholine, igands (native LDL, acetylated LDL), and liposome uptake
Language:
English
Description:
The macrophage cell-line J774.E1 and Leishmania m. mexicana infection was used to investigate the uptake of liposomes, which differed in their bulk phospholipid: ester- or ether-analogue of phosphatydilcholine (PC). The receptor-mediated uptake of both species of liposomes, containing native or acetylated LDL as ligands was also evaluated. Uninfected and infected J774.E1 cell-line accumulated more ester- and ether-liposomes alone than mixed type (50:50, ester/ether). The utilization was significantly enhanced when both types of liposomes contained native LDL. The highest uptake was recorded for liposomes bearing acetylated LDL by infected J774.E1 cells. Accumulation of ester- and ether-liposomes with the same ligand was not markedly affected by different chemical nature of PC. Finally, ether-liposomes alone possessed certain activity against Leishmania m. mexicana amastigotes. The results presented here demonstrated the usefulness of ether-liposomes with specific ligands in site-specific delivery of antileishmanial compounds in vitro.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Comparative studies on carbohydrates of several myxosporcan parasites of fish using lectin histochemical methods

Creator:
Muňoz, Pilar, Palenzuela, Oswaldo, Alvarez-Pellitero, Pilar, and Sitja-Bobadilla, Ariadna
Format:
print
Type:
model:internalpart and TEXT
Subject:
Myxozoa, parasites, lectins, histochemistry, Teleostei, and carbohydrates
Language:
English
Description:
A histochemical study using lectin methods was performed on myxosporean parasites from vastly different fish hosts from marine and fresh waters. Six biotinylated lectins were used (WGA, SBA, BS-I, Con-А, UEA-I and SNA). The binding paltem of Con-A and WGA revealed the presence of mannose and/or glucose, and N-acetyl-D-glucosamine respectively, in polar capsules and valves of most of the myxosporea assayed. Thus, chitin may be present in polar capsules and/or valves of myxosporean spores. The BS-I binding pattern showed the presence of a-!)-galactose and/or N-acetyl-D-galactosamine residues in polar capsules of Kudoa sp., Zschokkeìla mugilis Sitjà-Bobadilla et Alvarez-Pellitero, 1993 and Leplotheca sp., and in the valves of the latter. Scarce amounts of N-acetyl-D-galactosamine and/or α-D-galactose were demonstrated by SBA binding in Sphaerospora dicentrarchi Sitjà-Bobadilla et Alvarez-Pellitero 1992, Leplotheca sp. and Kudoa sp. valves, and in Leptotheca sp. polar capsules. The UEA-I staining indicated the absence ofa-L-fucose in all the myxosporea assayed except in Leptotheca sp. N-acety!neuraminic acid was detected with SNA in the polar capsules and sporoplasms of Polysporoptasma sparis Sitjà-Bobadilla et-Alvarez-Pellitero, 1995 and in the polar capsules and valves of Kudoa sp. These results indicate that, although Myxosporea may have conserved carbohydrate structures, some of them can show significantly different binding patterns, which may be useful in diagnostic and functional studies.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Contemporary problems of relativistic celestial mechanics and astrometry

Creator:
Brumberg, V. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
astronomical measurements, relativistic celestial mechanics, and relativistic astrometry
Language:
Czech
Description:
The general theory of relativity (GRT) should be considered at present as a necessary framework for the construction of accurate dynamical ephemerides (relativistic celestial mechanics) and In the discussion of high-precision observations (relativistic astrometry). The main achievements of recent years and the most promising investigations are related to experimental foundation of the theory of gravitation, gravltational radiation treated as the subject of celestial mechanics, mathematical correctness and physical meaning of the equatlons of motion, astronomical reference systems, time scales, astronomical units of measurements, reduction of astronomical observations.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

9. Contents of photosynthetic pigments and ratios of chlorophyll a/b and chlorophylls to carotenoids (a+b)/(x+c) in C4 plants as compared to C3 plants

Creator:
Lichtenthaler, H. K. and Babani, F.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
autumnal leaf senescence, C3 plants, C4 plants, chlorophyll contents, photosynthetic pigments, shade leaves, sun leaves, and total carotenoid content
Language:
Multiple languages
Description:
The content of chlorophylls (Chl) (a+b), total carotenoids (x+c), and the pigment ratios of Chl a/b and Chls to carotenoids (a+b)/(x+c) of green leaves of five C4 plants were determined and compared to those of C3 plants. The C4 plants were: Pacific and Chinese silvergrass (Miscanthus floridulus and Miscanthus sinensis), sugar cane (Saccharum officinarum) as well as feed and sugar maize (Zea mays). The three C3 plants were beech, ginkgo, and oak. C4 plants possess higher values for the ratio Chl a/b (3.4-4.5) as compared to the C3 plants (2.6-3.3). Sugar maize had the highest values for Chl a/b (4.04-4.70) and exceptionally high contents of total carotenoids and consequently lower values for the ratio of (a+b)/(x+c) (mean: 3.75 ± 0.6). During autumnal senescence also C4 plants showed a faster decline of Chl b as compared to Chl a yielding high values for Chl a/b of 6 to 8. Chlorophylls declined faster than carotenoids yielding low (a+b)/(x+c) values below 1.0.
Rights:
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10. Defence response produced during photodynamic damage in transgenic rice overexpressing 5-aminolevulinic acid synthase

Creator:
Jung, S., Back, K., Yang, K., Kuk, Y. I., and Chon, S.-U.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
5-aminolevulinic acid synthase, antheraxanthin, antioxidant, chlorophyll, non-photochemical quenching, Oryza, photodynamic stress, violaxanthin, and zeaxanthin
Language:
Multiple languages
Description:
Photodynamic and photoprotective responses at different irradiances were investigated in transgenic rice (Oryza sativa) expressing Bradyrhizobium japonicum 5-aminolevulinic acid synthase (ALA-S). With high irradiance (HI) of 350 µmol m-2 s-1, transgenic lines P5 and P14 showed a decrease in contents of chlorophyll (Chl) and the chloroplast-encoded gene psbA mRNA, whereas a decrease in light-harvesting Chl-binding proteins was observed only in P14. These effects were not observed in the wild-type (WT) line treated with HI or all of the lines treated with low irradiance (LI) of 150 µmol m-2 s-1. HI resulted in a greater decrease in the quantum yield of photosystem 2 and a greater increase in non-photochemical quenching (NPQ) in the transgenic lines, particularly in P14, compared to WT. Photoprotective zeaxanthin contents increased at HI, even though carotenoid contents were lower in the transgenic lines compared to WT. When exposed to HI, superoxide dismutase greatly increased in transgenic lines P5 and P14, but peroxidase and glutathione reductase increased only in P14, in which more photodynamic damage occurred. Thus the greater expression of ALA-S in the transgenic plants developed the stronger protective functions, i.e. the increased values of NPQ and zeaxanthin, as well as more photodynamic reactions, i.e. decreased photosynthetic component and efficiency, in the photosynthetic complexes. However, the photodynamic reactions indicate that the antioxidant capacity was insufficient to cope with the severe stress triggered by photoactive porphyrins in the transgenic rice expressing ALA-S. and S. Jung ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public