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572282. Spontaneous cystogenesis of Toxoplasma gondii in feline epithelial cells in vitro
- Creator:
- de Muno, Renata M., Moura, Marcos A., de Carvalho, Luciany C., Seabra, Sergio H., and Barbosa, Helene S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bradyzoites, felids cells, tachyzoites, tissue cysts in vitro, and toxoplasmosis
- Language:
- English
- Description:
- Toxoplasma gondii Nicolle et Manceaux, 1908 is an obligate intracellular parasite with the ability to infect mammals and birds. The only definitive hosts for T. gondii are felids, as the parasites form immature oocysts that are shed in the faeces. Here we introduce cat cells as a model for the study of experimental toxoplasmosis. We selected epithelial cells derived from cat kidneys (CRFK) as a target to determine the intracellular fate of bradyzoites of the T. gondii ME49 strain. In parallel, we compared this infection using epithelial cells from the rat intestine (IEC-6), considering the enteroepithelial development that occurs in the cat. Different ratios of parasites to host cells were assayed over the course of a 14-day-infection. The intracellular development of T. gondii was dependent on the source of the epithelial cells and also on the parasite/host cell ratio. Cystogenesis was well established in the CRFK cell line at a ratio of 1 : 10 after 10-14 days of infection. This cellular model system opens a new field of investigation into the molecular aspects of the interactions between T. gondii and feline epithelial cells. The CRFK cell line appears to be a potential cellular model for large scale cyst production in vitro, which would allow a reduction in the number of animals used and/or replacement of animals by in vitro cultures.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
572283. Spontaneous quantal and non-quantal release of acetylcholine at mouse endplate during onset of hypoxia
- Creator:
- Bukharaeva, E.A., Salakhutdinov, R.I., Vyskočil, F., and Nikolsky , E.E.
- Type:
- article, model:article, and TEXT
- Subject:
- Miniature potential, Acetylcholine, Quantal release, Non-quantal release, and Hypoxia
- Language:
- English
- Description:
- At 20oC, both quantal and non-quantal spontaneous acetylcholine release (expressed as miniature endplate potential frequency [f-MEPPs] and the H-effect, respectively) increased during the first 30 min of hypoxia in solution with normal extracellular calcium ([Ca2+]o = 2.0 mM). The hypoxia-induced tenfold increase of the f-MEPPs was virtually absent in low calcium solution ([Ca2+]o = 0.4 mM) whereas there was still a significant increment of non-quantal release. This indicates that each of these two processes of acetylcholine release is influenced by mechanisms with different oxygen sensitivity. The rise of f-MEPPs during the onset of hypoxia apparently requires Ca2+ entry into the nerve terminal, whereas the non-quantal release can be increased by another factors such as a lower level of ATP.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
572284. Spontaneous succession of vegetation in mined peatlands: a multi-site study
- Creator:
- Konvalinková, Petra and Prach, Karel
- Type:
- article and TEXT
- Subject:
- abiotic factors, bryophytes, mined peatland, ordination, restoration, successional age, and vascular plants
- Language:
- English
- Description:
- This study was conducted at 17 peatlands in the Czech Republic mined either by the traditional block-cut method or industrially. Phytosociological reléves of 5 × 5 m were carried out in representative parts of successional stages in disturbed peatlands. Age and environmental characteristics were assessed for each relevé (position of water table, water pH, substratum chemistry, geographical area) or each locality (altitude, average annual temperature and precipitation). Phytosociological reléves recorded in natural vegetation, representing the respective target stages, were included into some analyses. Altogether, 210 relevés were analysed by the DCA ordination. Separately, relevés from milled and block-cut sites were elaborated by CCA with marginal and partial effects calculated. Despite the great variability in vegetation, especially among industrially harvested sites, there is a general tendency for peatland vegetation to recover spontaneously, especially at traditionally harvested sites, which all were, however, older than 50 years. The vegetation at the younger industrially harvested sites exhibited only a tendency to recover. All environmental variables investigated had at least some significant effect on the vegetation pattern, among them, soil pH, water table, nitrates, successional age and geographical location were most important. Abiotic site factors together and geographical location appeared to be more important in determining species composition than successional age.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
572285. Spontaneous succession of vegetation on acidic bedrock in quarries in the Czech Republic
- Creator:
- Trnková, Romana, Řehounková, Klára, and Prach, Karel
- Type:
- article and TEXT
- Subject:
- Czech Republic, ordination, restoration, species pool, stone quarries, target species, and vegetation succession
- Language:
- English
- Description:
- Variability in vegetation, participation of target and non-target species and the role of the local species pool in the spontaneous succession on acidic bedrock were studied in quarries. The study was conducted in the Českomoravská vrchovina uplands (central Czech Republic). A total of 135 relevés, 5 × 5min size, were used to sample 41 quarries that were abandoned from 1 to 92 years ago. Three types of sites were distinguished: mesic, wet and periodically flooded. Species cover (seven point Braun-Blanquet scale) was visually estimated. The following characteristics were noted: steep rocky slopes, bottoms and levels, dumps and screes as habitat types; age; proportion of the main land-cover categories (arable land, ruderal and urban, grassland,woodland and wetland) in the surroundings up to 100 m and 1 km from each quarry; and the occurrence of target (grassland, woodland, wetland) and non-target (ruderal, alien) species up to 100 m from each quarry. Ordination indicates that the spontaneous succession of vegetation results in the formation of mixed woodland, Alnus and Salix carrs, or tall sedge and Typha beds with scattered Salix, depending on the wetness of a site, surrounding vegetation and land cover. Restoration of target vegetation in the quarries by spontaneous succession is possible and can occur within about 25 years, especially if the target species are present close by.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
572286. Spontaneous variability and reactive postural beat-to-beat changes of integral ECG body surface potential maps
- Creator:
- Eva Kellerová, Vavrinec Szathmáry, Kozmann, G., Katalin Haraszti, and Tarjányi, Z.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, integral ECG body surface maps, beat-to-beat variability, respiratory and low frequency oscillations, postural effects, 14, and 612
- Language:
- English
- Description:
- There is virtually no information on spontaneous variability of ECG body surface potential maps (BSPMs) and on dynamics of their reactive changes in healthy subjects. This study evaluated quantitatively the depolarization (QRS) and repolarization (QRST) parameters derived from the respective integral BSPMs, constructed beat-to-beat, from continual body surface ECG records in 9 healthy men resting supine, during head-up tilting and sitting. Spontaneous variability of the BSPMs parameters, both at rest and during postural reactions, was characterized by significant respiratory and low frequency oscillations, more pronounced when related to repolarization. Head-up tilting and sitting-up evoked significant decrease in the QRST-BSPM amplitudes, widening of the angle α and reduction of nondipolarity indexes, compared to the respective supine values. All these changes were gradual, characterized by transition phenomena and prolonged after-effect s. Tilting back to horizontal restored the resting supine va lues. The postural effects on depolarization were individually more variable and in the average showed a minimal QRS-BSPM amplitude increase. Beat-to-beat analysis of a train of ECG BSPMs provided the first evidence of spontaneous, non-random, respiratory and low frequency oscillations of the ventricula r repolarization pattern, and the first insight into the dynamics of body posture associated changes in ventricular recovery., E. Kellerová, V. Szathmáry, G. Kozmann, K. Haraszti, Z. Tarjányi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
572287. Spontaneous, L-arginine-induced and spironolactone-induced regression of protein remodeling of the left ventricle in L-NAME-induced hypertension
- Creator:
- Fedor Šimko, Anna Potáčová, Václav Pelouch, Ľudovít Paulis, Jana Matúšková, Kristína Krajčírovičová, Oľga Pecháňová, and Michaela Adamcová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kolagen, hypertenze, collagen, hypertension, L_NAME hypertension, L-arginine, spironolactone, regression of hypertrophy, 14, and 612
- Language:
- English
- Description:
- NG-nitro-L-arginine-methyl ester (L-NAME)-induced hypertension is associated with protein remodeling of the left ventricle. The aim of the study was to show, whether aldosterone receptor blocker spironolactone and precursor of NOproduction L-arginine were able to reverse the protein rebuilding of the left ventricle. Six groups of male Wistar rats were investigated: control 4 (4 weeks placebo), L-NAME (4 weeks L-NAME), spontaneous-regression (4 weeks L-NAME + 3 weeks placebo), spironolactone-regression (4 weeks L-NAME + 3 weeks spironolactone), L-arginineregression (4 weeks L-NAME + 3 weeks arginine), control 7 (7 weeks placebo). L-NAME administration induced hypertension, hypertrophy of the left ventricle (LV), and the increase of metabolic and contractile as well as soluble and insoluble collagenous protein concentration. The systolic blood pressure and relative weight of the LV decreased in all three groups with regression, while the most prominent attenuation of the LVH was observed after spironolactone treatment. In the spontaneous-regression and L-arginine-regression groups the concentrations of individual proteins were not significantly different from the control value. However, in the spironolactone-regression group the concentration of metabolic, contractile and insoluble collagenous proteins remained significantly increased in comparison with the control group. The persistence of the increased protein concentration in the spironolactone group may be related to the more prominent reduction of myocardial water content by spironolactone., F. Šimko, A. Potáčová, V. Pelouch, L'. Paulis, J. Matúšková, K. Krajčírovičová, O. Pecháňová, M. Adamcová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
572288. Spontaneously induced cellular immunity to HPV-16/18 and the therapeutic vaccination of patients with HPV-16/18 (pre-)malignant lesions
- Creator:
- van der Burg, Sjoerd H.
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
572289. Spontánní bakteriální peritonitida
- Creator:
- Šenkeříková, Renáta, Fraňková, Soňa, Šperl, Jan, and Špičák, Julius
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, přehledy, and TEXT
- Subject:
- peritonitida--diagnóza--etiologie--mortalita--patofyziologie--terapie, jaterní cirhóza--komplikace, ascites--diagnóza--etiologie--terapie, bakteriální infekce--diagnóza--terapie, antibakteriální látky--farmakologie, amoxicilin, klinický obraz nemoci, bakteriální léková rezistence, antibiotická profylaxe--využití, transplantace jater, and lidé
- Language:
- Czech and English
- Description:
- Spontánní bakteriální peritonitida (SBP) je častou a závažnou komplikací u pacientů s ascitem při jaterní cirhóze. Hospitalizační mortalita pacientů se SBP se pohybuje mezi 10–20 %, proto je nutné na ni pomýšlet při každém zhoršení stavu u cirhotika, včas ji diagnostikovat a účinně léčit. Klinický obraz je variabilní a nespecifický, až u 1/3 pacientů může probíhat onemocnění asymptomaticky. Pro diagnózu SBP je rozhodující počet neutrofilů v ascitické tekutině > 250 buněk/mm3. Bakteriologické vyšetření ascitu zachytí agens u méně než 1/2 případů a výsledek je k dispozici až po několika dnech. Léčbu je však nutno zahájit bezodkladně. SBP se léčí celkově podávanými antibiotiky, lékem první volby jsou cefalosporiny 3. generace, nejčastěji cefotaxim, alternativou jsou fluorochinolony. Dlouhodobá prognóza nemocných s prodělanou SBP je nepříznivá pro vysoký výskyt recidiv, jednoleté přežití po proběhlé epizodě SBP je 30–40 %, dvouleté 20 %. Tito nemocní mají proto dostávat dlouhodobou antibiotickou profylaxi a měla by být u nich zvážena transplantace jater., Spontaneous bacterial peritonitis (SBP) represents a frequent and serious complication in patients with ascites in liver cirrhosis. Hospital mortality in patients with SBP reaches 10–20 %, so it is necessary to consider this diagnosis in every clinical decompensation of a cirrhotic patient, diagnose it early and treat it effectively. The clinical manifestation is nonspecific and variable, up to one third of patients might be asymptomatic. The diagnosis of SBP is based on the ascitic neutrophils count greater than 250 per mm3. Bacteriological examination of ascites fluid detects causative agents at less than half of the cases and the result is available after a few days. However, treatment should be initiated without delay. SBP is generally treated with antibiotics, the first choice therapy are the third generation cephalosporins, mostly cefotaxime, alternatively fluoroquinolones. Long-term prognosis of patients with the history of SBP is poor owing to its high recurrence rate, one-year survival after an episode of SBP is 30–40 %, 20 % at two years. Therefore, these patients should receive long-term antibiotic prophylaxis and should be evaluated for liver transplantation., and Renáta Šenkeříková, Soňa Fraňková, Jan Šperl, Julius Špičák
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
572290. Spontánní narušení symetrie ve fyzice částic: případ mezidruhového křížení: nobelovská přednáška 8. prosince 2008
- Creator:
- Nambu, Yoichiro and Gregora, Ivan
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- elementární částice, particles (nuclear physics), CP symetrie, 6, and 539
- Language:
- Czech
- Description:
- Yoichiro Nambu ; přeložeil Ivan Gregora. and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public