Zinc (Zn) deficiency is a major problem for many people living on wheat-based diets. Here, we explored whether addition of green manure of red clover and sunflower to a calcareous soil or inoculating a non-indigenous arbuscular mycorrhizal fungal (AMF) strain may increase grain Zn concentration in bread wheat. For this purpose we performed a multifactorial pot experiment, in which the effects of two green manures (red clover, sunflower), ZnSO4 application, soil γ-irradiation (elimination of naturally occurring AMF), and AMF inoculation were tested. Both green manures were labeled with 65Zn radiotracer to record the Zn recoveries in the aboveground plant biomass. Application of ZnSO4 fertilizer increased grain Zn concentration from 20 to 39 mg Zn kg-1 and sole addition of green manure of sunflower to soil raised grain Zn concentration to 31 mg Zn kg-1. Adding the two together to soil increased grain Zn concentration even further to 54 mg Zn kg-1. Mixing green manure of sunflower to soil mobilized additional 48 µg Zn (kg soil)-1 for transfer to the aboveground plant biomass, compared to the total of 132 µg Zn (kg soil)-1 taken up from plain soil when neither green manure nor ZnSO4 were applied. Green manure amendments to soil also raised the DTPA-extractable Zn in soil. Inoculating a non-indigenous AMF did not increase plant Zn uptake. The study thus showed that organic matter amendments to soil can contribute to a better utilization of naturally stocked soil micronutrients, and thereby reduce any need for major external inputs.

• MeSH
• biologický transport MeSH
• biomasa MeSH
• chléb * MeSH
• dusík metabolismus   MeSH
• hnůj * MeSH
• koncentrace vodíkových iontů MeSH
• kyselina pentetová chemie   MeSH
• minerály chemie   MeSH
• mykorhiza fyziologie   MeSH
• průmyslová hnojiva analýza   mikrobiologie   MeSH
• pšenice metabolismus   mikrobiologie   MeSH
• půda chemie   MeSH
• rozpustnost MeSH
• zinek metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dusík MeSH
• hnůj * MeSH
• kyselina pentetová MeSH
• minerály MeSH
• průmyslová hnojiva MeSH
• půda MeSH
• zinek MeSH

The separation of light and heavy sludge, as well as the aggregation rate of floccular sludge, are two critical aspects of the rapid granulation process in sequencing batch reactors (SBRs) in the early stages. In this study, we investigated the impact of a method to improve both sludge separation and granulation by coupling effluent sludge external conditioning with FeCl3 addition and then reintroducing it into the SBR. By supplementation with 0.1 g Fe3+ (g dried sludge (DS))-1, the concentration of extracellular polymeric substances (EPS) and sludge retention efficiency greatly increased, whereas the moisture content and specific oxygen uptake rate (SOUR) sharply decreased within 24 h external conditioning. Aggregates (1.75 ± 0.05 g·L-1) were reintroduced into the bioreactor once daily from day 13 to day 15. Afterwards, on day 17, aerobic granules with a concentration of mixed liquor suspended solids (MLSS) of 5.636 g/L, a sludge volume index (SVI30) of 45.5 mL/g and an average size of 2.5 mm in diameter were obtained. These results suggest that the external conditioning step with both air-drying and the addition of Fe3+ enhanced the production of EPS in the effluent sludge and improved rapid aggregation and high sludge retention efficiency. Consequently, the reintroduced aggregates with good traits shortened the time required to obtain mature aerobic granular sludge (AGS) and properly separate light and heavy sludge. Indeed, this method jump-started the aggregation, and rapid granulation processes were successful in this work. Additionally, while the removal efficiency of chemical oxygen demand (COD) and nitrogen from ammonium (NH4+-N) decreased when reintroducing the treated sludge into the SBR, such properties increased again as the AGS matured in the SBR, up to removal efficiencies of 96% and 95%, respectively.

• Klíčová slova
• Fe3+ addition, external conditioning, extracellular polymeric substances, rapid granulation, reintroduction,
• Publikační typ
• časopisecké články MeSH

Cell-based bioassays are very sensitive and allow integrative effect screening of the whole environmental sample, which is usually composed of a mixture of agonists and antagonists. Measured toxicity is usually expressed as a bioanalytical equivalent concentration. So far, it is not possible to distinguish which part of this value is caused by the agonists and which by the antagonists. In this article, we present a simple method to analyze the dose-response curve of a mixture and to determine an agonistic bioanalytical equivalent concentration: a concentration of a reference chemical that would elicit the same effect as do only agonists in an unknown mixture. The method has been validated using several artificially prepared mixtures of agonists and competitive antagonists measured in a recombinant yeast assay. No difference was observed between the calculated equivalent concentrations and the used concentrations of the agonist in the mixture.

• Klíčová slova
• Bioanalytical equivalent concentration, Competitive antagonist, Concentration addition, Effect-based methods, Endocrine disruptors, Mixture toxicity,
• MeSH
• biotest metody   MeSH
• endokrinní disruptory * MeSH
• estradiol farmakologie   MeSH
• estriol farmakologie   MeSH
• fulvestrant farmakologie   MeSH
• látky znečišťující životní prostředí toxicita   MeSH
• lékové interakce MeSH
• receptory pro estrogeny antagonisté a inhibitory   MeSH
• Saccharomyces cerevisiae účinky léků   MeSH
• teoretické modely MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• endokrinní disruptory * MeSH
• estradiol MeSH
• estriol MeSH
• fulvestrant MeSH
• látky znečišťující životní prostředí MeSH
• receptory pro estrogeny MeSH

Paced Auditory Serial-Addition Task (PASAT) is a complex task commonly used to examine patients with diffuse brain damage. A visual version of the neuropsychological test (Paced Visual Serial-Addition Task, PVSAT) has also been introduced to clinical practice, and both versions were adapted to be used in neuroimaging, namely functional magnetic resonance imaging (fMRI). The aim of our work was direct comparison of auditory and visual versions of the paced serial addition test (PASAT/PVSAT) in a within-subject and within-session study and description of the commonalities and differences in both activated and deactivated brain regions. Twenty young adult right-handed healthy volunteers participated in the study and underwent whole-brain fMRI examination during PASAT and PVSAT performance. Higher-level statistical analysis was performed to generate group mean activation and deactivation maps for both tasks, their conjunctions and differences across modalities. In PASAT/PVSAT activation conjunction analysis, we confirmed the existence of a modality-independent neural network similar to working memory tasks and to previous PASAT or PVSAT studies. In PASAT/PVSAT deactivation conjunction analysis, we observed a rather symmetrical extensive pattern of deactivated regions, overlapping the default mode network. Significant differences between PASAT and PVSAT were found in the right frontal eye field (FEF) and bilaterally in the striate and extrastriate cortices. Activation in one task and deactivation in the other jointly contributed to significant differences in all occipital and occipitotemporal regions. Both tasks activated right FEF, but activation during PASAT was significantly stronger than during PVSAT. Between-modality differences should be considered when preparing and interpreting neuroimaging experiments.

• Klíčová slova
• PASAT, PVSAT, deactivation, default mode network, fMRI, verbal working memory,
• MeSH
• akustická stimulace * MeSH
• dospělí MeSH
• kognice fyziologie   MeSH
• krátkodobá paměť fyziologie   MeSH
• lidé MeSH
• magnetická rezonanční tomografie metody   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mozek fyziologie   MeSH
• neuropsychologické testy MeSH
• plnění a analýza úkolů MeSH
• pozornost fyziologie   MeSH
• světelná stimulace * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The presented study is devoted to the investigation of the micellization-induced liquid-liquid fluctuations in sodium decanoate (NaD) aqueous solutions, based on the vibrational spectroscopic study of NaD and the determination of critical micelle concentration (CMC) of this system. At the same time, we focused on monitoring the effect of the addition of decanol to this system and changing its basic parameters from the point of view of CMC. CMC is an important parameter from a practical point of view and a characteristic feature of each micelle-forming compound. Upon analyzing the spectroscopic data we focus our attention mainly on the intensity and band position variations of both the symmetrical and antisymmetrical vibrational modes of CH2 groups situated in the high-frequency part of the spectrum. The study used normal (non-enhanced) Raman spectroscopy with excitation wavelength 785 nm, surface-enhanced Raman spectroscopy (SERS) on large-scaled gold-coated SERS-active substrates and infrared spectral measurements. The results of spectroscopic measurements were supported by tensiometry and potentiometry.

• Klíčová slova
• Critical micelle concentration, Raman spectroscopy, Sodium decanoate, Vibrational spectroscopy,
• Publikační typ
• časopisecké články MeSH

The urea concentration in the renal cortex ([RC]) of pentobarbital-anaesthetized dogs was 5.71 times higher than the plasma concentration ([P]); the liver ([L]) and the skeletal muscle ([SM]) concentrations were the same as ([P]). Rapid infusion of 20% urea (1 g/kg b.w. within 1 min) was followed by a sudden increase in [P]; [RC] and [L] rose to values nonsignificantly different from [P] and remained non-significantly different for the whole 4 hours of the experiment; at the end, [P] was still about 10 times higher than before infusion. Surprisingly, [SM] 2 and 6 min after infusion was significantly lower than [P]; later they were the same. The experiment thus does not testify to the existence of active transport of urea in the RC. The permeability of the skeletal muscle membrane for urea is lower than that of the RC and liver. Chronic uraemia was induced in rats by transplanting the trigonum vesicae into the peritoneal cavity. In addition to the chemical determination of urea, 14C-urea (marked*) was also measured. [RC]/[P] and [RC*]/[P*] fell as [P] rose; [L], [L*] [SM] and [SM*] never differed from [P] or [P*]. Fluid [PF] collected in the peritoneal cavity had the same chemically determined and radioactive urea concentration as P, but it was hypoosmolar and had a lower [Na+] than P. These experiments likewise did not testify to active urea transport in the RC. It is not clear what caused the osmolarity and sodium gradient between the PF and P, but the peritoneal wall definitely did not act as a simple dialyzing membrane.

• MeSH
• biologický transport MeSH
• extracelulární prostor metabolismus   MeSH
• inbrední kmeny potkanů MeSH
• játra metabolismus   MeSH
• kinetika MeSH
• krysa rodu Rattus MeSH
• kůra ledviny metabolismus   MeSH
• močovina krev   metabolismus   MeSH
• osmolární koncentrace MeSH
• peritoneum MeSH
• psi MeSH
• sodík metabolismus   MeSH
• svaly metabolismus   MeSH
• tkáňová distribuce MeSH
• uremie metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• psi MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• močovina MeSH
• sodík MeSH

• MeSH
• alkany farmakologie   MeSH
• aminy farmakologie   MeSH
• antifungální látky farmakologie   MeSH
• Candida albicans účinky léků   růst a vývoj   MeSH
• chemické jevy MeSH
• chemie MeSH
• fenoly farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• spektrofotometrie MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alkany MeSH
• aminy MeSH
• antifungální látky MeSH
• fenoly MeSH

Albumin and hyaluronic acid are biodegradable, endogenous substances with potential use as drug carriers. These properties combined with the physical structure of the gel can lead to the formation of biologically active materials with application in medicine. This work investigated the gelation process of albumin solutions and mixed solutions of albumin and hyaluronan due to heating. The influence of the polymer concentration, weight ratio of hyaluronan and albumin, ionic strength, pH and molecular weight of hyaluronan is discussed. The study was carried out by measuring the rheological properties of the solutions, formed gels, and the gelation process. With increasing albumin concentration, the gel point was shifted towards lower temperature values. The resulting gels exhibited higher values of loss and storage moduli. For the mixed solutions of protein and polysaccharide, the effect of the polysaccharide concentration was observed. Based on the measurements, it can be assumed that the dependence of the complex modulus on the polysaccharide concentration has a peak at the certain hyaluronan: albumin weight ratio. The measured data showed, that increasing the ionic strength led to higher complex modulus values of the gels, and also to the increase of the temperature of the gel point. The gelation proceeded significantly faster when pH < pIBSA in comparison with the samples with pH > pIBSA. Increasing the pH of the solution (with respect to the albumin stability) led to higher complex modulus values of the gels formed. As a result of lowering the molecular weight of hyaluronan, the gel point was shifted towards lower temperature values, and resulting gels exhibited higher values of complex modulus. In addition, the ability of mixed BSA-HA solutions to bind hydrophobic substances was proven.

• Klíčová slova
• Albumin, Gelation, Hyaluronan, Hydrogels, Rheology,
• MeSH
• hydrogely chemická syntéza   chemie   MeSH
• koncentrace vodíkových iontů MeSH
• kyselina hyaluronová chemie   MeSH
• molekulová hmotnost MeSH
• osmolární koncentrace MeSH
• reologie MeSH
• sérový albumin hovězí chemie   MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydrogely MeSH
• kyselina hyaluronová MeSH
• sérový albumin hovězí MeSH

The study investigates the role of biochar and/or compost in mitigating the toxic effects of pyrene in soils using reproduction of nematodes and porewater concentration as measures of pyrene toxicity and bioavailability, respectively. Two soils were spiked with increasing levels of pyrene to achieve a concentration-response relationship for the reproduction of Caenorhabditis elegans. The observed EC50 values (pyrene concentration causing 50% inhibition of reproduction) were 14mg/kg and 31mg/kg (dry mass) for these soils, corresponding to equilibrium porewater concentrations of 37μg/L and 47μg/L, respectively. Differences in organic carbon content were not sufficient to explain the variability in toxicity between the different soils. Soils causing a significant inhibition of reproduction were further amended with 10%-compost, 5%-biochar, or both, and the effects on reproduction and porewater concentration determined. Combined addition of compost and biochar was identified as the most effective strategy in reducing pyrene concentration in soil porewater, which was also partly reflected in soil toxicity. However, porewater concentrations predicted only 52% of pyrene toxicity to nematodes, pointing to particle-bound or dietary exposure pathways. Capsule: Amending pyrene-spiked soil with biochar and compost effectively reduced pyrene porewater concentrations and toxicity to nematodes, which were significantly related.

• Klíčová slova
• Biochar, Compost, Nematodes, Pyrene toxicity, Solid-phase microextraction, Sorption,
• MeSH
• biologická dostupnost MeSH
• Caenorhabditis elegans účinky léků   MeSH
• dřevěné a živočišné uhlí chemie   MeSH
• kompostování MeSH
• látky znečišťující půdu toxicita   MeSH
• půda chemie   MeSH
• pyreny toxicita   MeSH
• rozmnožování účinky léků   MeSH
• testy toxicity MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biochar MeSH Prohlížeč
• dřevěné a živočišné uhlí MeSH
• látky znečišťující půdu MeSH
• půda MeSH
• pyreny MeSH

Addition of hydrogen peroxide (greater than 10 mM) to aerated derepressed cells of S. cerevisiae in the absence of substrate caused a boost of endogenous respiration and both intra- and extracellular acidification, without any significant change in cellular ATP level. Furthermore, a hyperpolarization of the plasma membrane was indicated by an enhanced accumulation of tetraphenylphosphonium in the cells. The extracellular pH attained was as low as 3.5. The acidification could be suspended by the H(+)-ATPase inhibitors diethylstilbestrol and dicyclohexylcarbodiimide and was, in general, associated with an opposite flux of K+. K+ also stimulated the H(+)-ATPase activity in the purified plasma membrane fraction. These results are consistent with the plasma membrane H(+)-ATPase being involved in the H+ extrusion induced by H2O2 in the absence of substrate. Extended exposure of cells to H2O2 led eventually to an arrest of both respiration and ion fluxes that could be again lifted by depolarizing the plasma membrane. Along with differences in the cellular NADH/NAD+ ratio and in the participation of organic acids, this makes the H2O2-induced acidification distinct from that induced by glucose.

• MeSH
• aktivace enzymů MeSH
• buněčná membrána enzymologie   MeSH
• dicyklohexylkarbodiimid farmakologie   MeSH
• diethylstilbestrol farmakologie   MeSH
• draslík metabolismus   MeSH
• karbonylkyanid-m-chlorfenylhydrazon farmakologie   MeSH
• koncentrace vodíkových iontů MeSH
• NAD metabolismus   MeSH
• oniové sloučeniny MeSH
• organofosforové sloučeniny MeSH
• oxidace-redukce MeSH
• peroxid vodíku farmakologie   MeSH
• protonové ATPasy metabolismus   MeSH
• pufry MeSH
• Saccharomyces cerevisiae enzymologie   MeSH
• spotřeba kyslíku MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dicyklohexylkarbodiimid MeSH
• diethylstilbestrol MeSH
• draslík MeSH
• karbonylkyanid-m-chlorfenylhydrazon MeSH
• NAD MeSH
• oniové sloučeniny MeSH
• organofosforové sloučeniny MeSH
• peroxid vodíku MeSH
• protonové ATPasy MeSH
• pufry MeSH
• tetraphenylphosphonium MeSH Prohlížeč