An interference between a thermosensitive (ts) mutant and the wild-type (wt) of tick-borne encephalitis (TBE) virus in Ixodes ricinus L, and Rhipicephalus appendicuiatus (Neumann) ticks is reported. /. ricinus females were dually infected by a parenteral inoculation of ts and wt strains at 10-day interval. Interference was demonstrated by the lowered ability of wt virus to replicate in ticks previously infected by ts virus. The wt virus was demonstrated in only 30% of the ticks; the average virus titre was lowered by 2.1 log|0 compared with the control group, which was infected with the wt virus only. The oral infection of R. appendicuiatus ticks with the same viruses also revealed an interference with the growth of the superinfecting wt virus. While in the control group all the ticks became infected, in the dually infected group the wt virus was found in only 50% of the ticks. However, when the ticks were infected orally with is virus and superinfected parenterally with the wt virus, no interference was observed. In a R. appendicuiatus-derived cell line persistently infected with the ts virus (100% of the cells), a partial inhibition of the growth of the superinfecting wt virus was observed. The ts virus retained its thermosensitive phenotype throughout the persistent infection of both the ticks and the tick cell line.
The effect of CO2 increase on gas exchange and water-use effíciency (WUE) in three temperate deciduous species (Fagus crenata, Ginkgo biloba and Alnus firma) under gradually-developing drought-stress was assessed. Seedlings were grown within transparent open-top cabinets and maintained for 4 monťhs at mean CO2 concentrations of either 350 (ambient; C350) or 700 pmol moT’ (elevated; C700) and combined with five water regimes [leaf water potential, higher than -0.3 (well- watered), -0.5 and -0.8 (moderate drought), -1.0 and lower than -1.2 MPa (serious drought-stress)]. Increase in CO2 concentration induced a 60 % average increase in net photosynthetic rate (P^) under well-watered conditions. The effect of C700 became more pronounced with drought stress established, with an 80 % average increase in at as low as -0.8 MPa; leaf conductance to water vapour transfer (gs) and transpiration rate (£), however, were significantly decreased. Consequently, WUE increased under drought, through drought stress affected potential E sooner than potential P^. The interaction of CO2 x drought stress on WUE was significant in that Pn was stimulated while E in C700 enriched plants resembled that of C350 plants under drought. Hence if a doubling of atmospheric CO2 concentration occurs by the mid 2U* century, then greater P^ in F. crenata, G. biloba and^. firma may be expected and the drought susceptibility of these species will be substantially enhanced.
Galanin (GAL) is suggested to be a neuropeptide involved in pain transmission. In this study we tried to determine, whether the increase of GAL concentration in brain cells affects impulse transmission between the motor centers localized in the vicinity of the third and fourth cerebral ventricles. The experiments were carried out on rats under chloralose anesthesia. The study objectives were realized using the method allowing to record the amplitude of evoked tongue jerks (ETJ) in response to noxious tooth pulp stimulation during the perfusion of the cerebral ventricles with solutions containing tested compounds. Perfusion of the cerebral ventricles with GAL concentration-dependently inhibited the ETJ amplitude. The antinociceptive effect of GAL was blocked by a galanin receptor antagonist, galantide (GLT) and by opioid antagonists: non-selective naloxone (Nal) and μ-selective β-funaltrexamine (β-FNA). In contrast, a δ-opioid receptor antagonist, naltrindole (NTI) or the κ-opioid receptor antagonist, nor-binaltrophimine (nor-BNI) did not inhibit the effect of GAL. The antinociceptive effect of GAL was more pronounced when GAL was perfused in combination with other neuropeptides/neurohormones, such as endomorphin-2 (EM-2), vasopressin (AVP) and oxytocin (OT). The present results demonstrate that in the orofacial area analgesic activity is modulated by GAL, OT and AVP and that EM-2-induced antinociception involves GAL., M. Zubrzycka, A. Janecka., and Obsahuje bibliografii a bibliografické odkazy
Endothelin-1 (ET-1) and Nerve Growth Factor (NGF) are proteins, released from cancer-ridden tissues, which cause spontaneous pain and hypersensitivity to noxious stimuli. Here we examined the electrophysiological and behavioral effects of these two agents for evidence of their interactions. Individual small-medium cultured DRG sensory neurons responded to both ET-1 (50 nM, n=6) and NGF (100 ng/ml, n=4), with increased numbers of action potentials and decreased slow K+ currents; pre-exposure to ET-1 potentiated NGF´s actions, but not vice versa. Behaviorally, single intraplantar (i.pl.) injection of low doses of ET-1 (20 pmol) or NGF (100 ng), did not increase hindpaw tactile or thermal sensitivity, but their simultaneous injections sensitized the paw to both modalities. Daily i.pl. injections of low ET-1 doses in male rats caused tactile sensitization after 21 days, and enabled further tactile and thermal sensitization from low dose NGF, in ipsilateral and contralateral hindpaws. Single injections of 100 ng NGF, without changing the paw’s tactile sensitivity by itself, acutely sensitized the ipsilateral paw to subsequent injections of low ET-1. The sensitization from repeated low ET-1 dosing and the cross-sensitization between NGF and ET-1 were both significantly greater in female than in male rats. These findings reveal a synergistic interaction between cutaneously administered low doses of NGF and ET-1, which could contribute to cancer-related pain., A. Khodorova, Y. Zhang, G. Nicol, G. Strichartz., and Seznam literatury
The interactive effects of NO3 fertilization and salinity levels on leaf CO2 fixation, the dry matter accumulation, the proline and sugar contents in tomato shoots were determined in a greenhouse experiment using a well-controlled aerohydroponic systém. Under high salinity levels, increasing N fertilization from 5 mM NO3 up to 20 mM NO3 was ineffective in countering adverse effects of growth. Photosynthesis was inhibited as a result of both osmotic and specific ion effects. The high šalině concentrations stimulated the sugar accumulation in leaves, whereas the proline accumulation was primarily induced by increased NO3 levels.
Elevated atmospheric CO2 concentration [CO2] and the change of water distribution in arid and semiarid areas affect plant physiology and ecosystem processes. The interaction of elevated [CO2] and drought results in the complex response such as changes in the energy flux of photosynthesis. The performance of photosystem (PS) II and the electron transport were evaluated by using OJIP induction curves of chlorophyll a fluorescence and the PN-Ci curves in the two-factor controlled experiment with [CO2] of 380 (AC) or 750 (EC) [μmol mol-1] and water stress by 10% polyethylene glycol 6000. Compared to water-stressed maize (Zea mays L.) under AC, the EC treatment combined with water stress decreased the number of active reaction centers but it increased the antenna size and the energy flux (absorbed photon flux, trapping flux, and electron transport flux) of each reaction center in PSII. Thus, the electron transport rate was enhanced, despite the indistinctively changed quantum yield of the electron transport and energy dissipation. The combination of EC and the water-stress treatment resulted in the robust carboxylation rate without elevating the saturated photosynthetic rate (Pmax). This study demonstrated that maize was capable of transporting more electrons into the carboxylation reaction, but this could not be used to increase Pmax under EC., Y. Z. Zong, W. F. Wang, Q. W. Xue, Z. P. Shangguan., and Obsahuje bibliografii
We introduce an interactive seismic viewer "OP" (developed in MATLAB platform), primary designated for detailed processing of selected events. Few examples of graphical outlook are presented (main display window, particle motion diagram, etc.), available tools are briefly described, uncommon special tools (simultaneous display of original and filtered signal or time-spatial correlation of seismogram components) are emphasized. Features of the viewer are discussed, some programming solutions are also mentioned., Petr Kolář., and Obsahuje bibliografii
Pražské Letňany přilákaly ve dnech 19. až 21. května 2016 na 14 000 lidí, zvědavých, co pro ně připravilo 30 pracovišť Akademie věd i další popularizátoři na letošním „Veletrhu vědy“. Bohatý program s bezpočtem interaktivních exponátů z přírodovědných, technických a letos poprvé i humanitních oblastí oslovil návštěvníky všeho věku, od předškolních dětí až po seniory - Akademický bulletin nevyjímaje. and Gabriela Adámková a Jana Olivová.
Ultrazvuk, představující akustické kmity prostředí o specifických frekvencích, je jedním z mnoha fyzikálních činitelů, které se mohou uplatnit při interakcích s biologickými objekty. Posouzení účinků ultrazvukového pole na biologické systémy je možné hodnotit dle různých klasifikačních kritérií, např. dle povahy interakčního procesu, dle interagujících biologických struktur či výsledného "produktu". Při snaze o vytvoření univerzálního modelu interakce ultrazvuku a biologických struktur hraje velkou roli variabilita biologického materiálu a jeho různorodá odezva na aplikované ultrazvukové pole, což situaci velmi ztěžuje. Přesto nese ultrazvukové pole potenciál vysoké využitelnosti v oblasti medicíny a přírodních věd., Ultrasound, representing the acoustic vibrations of medium with specific frequencies is one of many physical factors that can interact with biological objects. Assessment of the effects of ultrasonic field on biological systems can be evaluated according to different classification criteria, such as the nature of the interaction process, by the character of interacting biological structures or by the final process "product". In an effort to create a universal model of interaction of ultrasound and biological structures the variability of biological materials and its changeable response to the applied ultrasonic field plays an important role, which makes this process very difficult. Yet, after all, ultrasonic field has a high application potential in the field of medicine and science., Vladan Bernard, Vojtěch Mornstein, Jiřína Škorpíková, Naděžda Vaškovicová., and Obsahuje bibliografii