Cryptosporidium parvum causes life-threatening diarrhoea in immunocompromized, especially AIDS patients and the efficiency of proposed anti-cryptosporidial therapies is limited or doubtful. An immunosuppressed adult rat model of C. parvum infection was developed for screening molecules candidate for curative and preventive activity in human cryptosporidiosis. Among 31 drugs tested, lasalocid (2-10 mg/kg/24 h), and sinefungin (2-10 mg/kg/24 h), exhibited some activity against C. parvum infection. Oral sinefungin therapy resulted in a dose related suppression of oocysts shedding, which correlated with oocyst disappearance from ileum sections and was also efficient in preventing infection. Relapses were observed after discontinuation of curative sinefungin therapy, which suggests that the biliary tract, a major location and parasite reservoir which sustains persisting infection, was not cleared of parasites by the drug. Improved therapeutic procedures with sinefungin (or analogues) will result from current pharmacological studies.
The photosynthetic gas-exchange has been assessed traditionally either as O2 evolution or CO2 consumption. In this study, we used a liquid-phase O2 electrode combined with CO2 optodes to examine simultaneously photosynthesis in intact leaves of mangrove Rhizophora mucronata. We verified suitable conditions for leaf photosynthetic rates by assessing pH levels and NaHCO3 concentrations and compared these to the gas-exchange method at various PAR levels. The photosynthetic rate in response to pH exhibited a similar pattern both for O2 evolution and CO2 consumption, and higher rates were associated with intermediate pH compared with low and high pH values. The net photosynthetic quotient (PQ) of R. mucronata leaves ranged from 1.04-1.28. The PQ values, which were never lesser than 1, suggested that photorespiration did not occur in R. mucronata leaves under aqueous conditions. The similar maximum photosynthetic rates suggested that all measurements had a high capacity to adjust the photosynthetic apparatus under a light saturation condition. The simultaneous measurements of O2 evolution and CO2 consumption using the Clark oxygen electrode polarographic sensor with the CO2 optode sensor provided a simple, stable, and precise measurement of PQ under aqueous and saturated light conditions., T. Z. Ulqodry, A. Nose, S.-H. Zheng., and Obsahuje seznam literatury
In the general tropospheric tomography model, the tomographic area is divided into a large number of voxels, which provides convenience for reconstructing tomographic observation equations. However, due to the defect of GNSS acquisition geometry, there are plenty of empty voxels for any tomographic epoch. Moreover, an unreasonable assumption that water vapor density is constant within a voxel was imposed on the tomographic model. In this study, we proposed an improved method based on the dynamic node parameterized algorithm to solve both key problems. The proposed approach first tries to select effective GNSS signals and determines the dynamic scope of the tomographic area using the dynamic algorithm. The parameterization of the tomography model is performed by a cubic spline formula and Gauss weighted function. Additionally, a piecewise linear fitting method based on Newton-Cotes interpolation is introduced to estimate the tomographic observation of slant water vapor (SWV). The experimental results show that the average number of effective signals increased by 32.33 % and the mean RMSE of the tomographic results is decreased by 45 % with the proposed method. Further, compared with the tomographic results of the general method, the improved solutions have a more centralized distribution and a smaller bias., Wenyuan Zhang, Shubi Zhang, Nan Ding and Pengxu Ma., and Obsahuje bibliografii
The hormone leptin, which is thought to be primarily produced by adipose tissue, is a polypeptide that was initially characterized by its ability to regulate food intake and energy metabolism. Leptin appears to signal the status of body energy stores to the brain, resulting in the regulation of food intake and whole-body energy expenditure. Subsequently, it was recognized as a cytokine with a wide range of peripheral actions and is involved in the regulation of a number of physiological systems including reproduction. In the fed state, leptin circulates in the plasma in proportion to body adiposity in all species studied to date. However other factors such as sex, age, body mass index (BMI), sex steroids and pregnancy may also affect leptin levels in plasma. In pregnant mice and humans, the placenta is also a major site of leptin expression. Leptin circulates in biological fluids both as free protein and in a form that is bound to the soluble isoform of its receptor or other binding proteins such as one of the immunoglobulin superfamily members Siglec-6 (OBBP1). Although the actions of leptin in the control of reproductive function are thought to be exerted mainly via the hypothalamicpituitary-gonadal axis, there have also been reports of local direct effects of leptin at the peripheral level, however, these data appear contradictory. Therefore, there is a need to summarize the current status of research outcomes and analyze the possible reasons for differing results and thus provide researchers with new insight in designing experiments to investigate leptin effect on reproduction. Most importantly, our recent experimental data suggesting that reproductive performance is improved by decreasing concentrations of peripheral leptin was unexpected and cannot be explained by hypotheses drawn from the experiments of excessive exogenous leptin administration to normal animals or ob/ob mice., M. Herrid, S. K. A. Palanisamy, U. A. Ciller, R. Fan, P. Moens, N. A. Smart, J. R. McFarlane., and Obsahuje bibliografii
Mediální dialog ztrácí některé rysy přirozeného dialogu tváří v tvář, který leží v jeho půdorysu, a získává rysy další, neboť komunikace tu přestupuje přes hranice primární řečové situace. Televizní dialog je dialog veřejný, který se vede před diváckým publikem a pro toto publikum. Divák je nejen svědkem, ale pravým cílem, k němuž je dialog směrován. Stať analyzuje komunikační situaci, při níž jsou ve studiu přítomni redaktor a dva hosté, představitelé různých profesí a názorových proudů (ekonom a ekoložka) i různých stanovisek к určité otázce (globalizace). Redaktor se obrací s otázkami střídavě к oběma. aby je vzájemně konfrontoval a spor vyhrotil. Dotazovaní hosté se snaží nejen odpovídat na otázky redaktora (to je jejich základní role v interview), ale i zpochybňovat či přímo vyvracet odpovědi druhého z hostí (role často neméně důležitá). Hosté komunikují nejen s redaktorem, ale komunikují i mezi sebou navzájem, ať už skrytě, či zjevně, s cílem získat diváka na svou stranu. Stať analyzuje toto interview v souvislosti s otázkou typologie debat a debat založených na konfliktu zájmů a konfliktu hodnot.
Turnover of Dl protein as influenced by actual irradiance and growth irradiance was analyzed in the photoautotrophic suspension cultured cells of Chenopodium rubrum. Proteins were labelled by adding 35S-methionine to the ceU suspension. Following electrophoresis the labelled proteins were detected by autoradiography. Relative label incorporation into the Dl protein containing band was calculated from scans of the autoradiographs and ušed as an estimate of Dl protein synthesis (pulse experiments) and Dl protein degradation (chase experiments). Total label incorporation was not affected by the irradiance during labelling but Dl protein synthesis and degradation were boťh increased at 900 pmol m-2 s*i as compared to 120 pmol m'2 s*^ The effect of growth irradiance was analysed by comparing cells which had been pre-cultured at 120 pmol m'2 s"^ (HL cells) and 900 pmol s‘i (PIL cells) for at least 6 d. The inhibition of chloroplastic protein synthesis by cUoramphenicol exacerbated the effect of photoinhibitory irradiance on the chlorophyll fluorescence parameters in these cells. The inhibitor effect was more pronoímced in PIL cells than in HL ones. This points to a higher chloroplastic protein synthesis capacity of the former cell type. Due to a considerable difference in total label incorporation pulse experiments could not be ušed to check this hypothesis. The chase experiments indicated that the Dl-protein degradation rate was higher in PIL cells tiian in HL cells. Probably a generál increase in the Dl protein tumover occiu^ if the cells are exposed to photoinhibitory irradiances for a prolonged period.
a1_Using magnetic resonance imaging (MRI) in conjunction with synchronized spirometry we an alyzed and compared diaphragm movement during tidal breathing and voluntary movement of the diaphragm while breath holding. Breathing cycles of 16 healthy subjects were examined using a dynamic sequence (77 slices in sagittal plane during 20 s, 1NSA, 240x256, TR4.48, TE2.24, FA90, TSE1, FOV 328). The amplitude of movement of the apex and dorsal costophren ic angle of the diaphragm were measured for two test conditions: tidal breathing and voluntary breath holding. The maximal inferior and superior positions of the diaphragm were subtracted from the corresponding positions during voluntary movements while breath holding. The average amplitude of inferio-superior mo vement of the diaphragm apex during tidal breathing was 27.3±10.2 mm (mean ± SD), and during voluntary movement while breath holding was 32.5±16.2 mm. Movement of the costophrenic angle was 39±17.6 mm during tidal breathing and 45.5±21.2 mm during voluntary movement while breath holding. The inferior position of the diaphragm was lower in 11 of 16 subjects (68.75 %) and identical in 2 of 16 (12.5 %) subj ects during voluntary movement compared to the breath holding. Pearson’s correlation coefficient was used to demonstrate that movement of the costophrenic angle and apex of the diaphragm ha d a linear relationship in both examined situations (r=0.876). A correlation was found between the amplitude of diaphragm movement during tidal breathing and lung volume (r=0.876). The amplitude of movement of the diaphragm with or without breathing showed no correlation to each other (r=0.074). The moveme nt during tidal breathing shows a correlation with the changes in lung volumes. Dynamic MRI demonstrated that individuals are capable of moving their diaphragm voluntarily, but the amplitude of movement differs from person to person., a2_In this study, the movements of the diaphragm apex and the costophr enic angle were synchronous during voluntary movement of the diaphragm while breath holding. Although the sample is small, this study confirms that the function of the diaphragm is not only respiratory but also postural and can be voluntarily controlled., P. Kolář, J. Neuwirth, J. Šanda, V. Suchánek, Z. Svatá, J. Volejník, M. Pivec., and Obsahuje bibliografii
Water is one of the most important components of the environment, having a direct effect on the maintenance of life on the Earth. In this paper, analysis of groundwater level variations, water balance and all the parameters included in these quantities, i.e. precipitation, evapotranspiration, surface run-off and subsurface run-off, were performed in the area of the Sudety Mountains for the period of November 2002 - October 2015. The groundwater level variations were computed on the basis of the mean Terrestrial Water Storage (TWS) values determined from Gravity Recovery and Climate Experiment (GRACE) observations and Global Land Data Assimilation System (GLD AS). TWS data have been determined with a spatial resolution of one degree and temporal resolution of one month. According to the results, groundwater level variation can be approximately determined by water balance changes (with reverse sign). Specifically, for the Sudety area a high average stability of total water storage over the period of past 13 years and decline in groundwater level by about 13 cm (approximately 1 cm/year) was detected., Zofia Rzepecka, Monika Birylo, Joanna Kuczynska-Siehien, Jolanta Nastula and Katarzyna Pajak., and Obsahuje bibliografické odkazy