Interactive effects of nitrogen, UV and PAR on barley morphology and biochemistry are associated with the leaf C:N balance

Environmental conditions to which plants acclimate prior exposure to abiotic or biotic stressors can greatly affect their subsequent resilience. This may have a significant impact on the response to ongoing climate change and can be useful for increasing the food security under adverse weather conditions associated with climate change.Within this study, we tested the hypothesis that plant morphological and biochemical acclimation to radiation conditions and nitrogen (N) availability is closely linked with carbon (C) and N balance. Four barley (Hordeum vulgare) varieties, differing in their morphological characteristics and sensitivity to photooxidative stress, were grown at two levels of N supply and four radiation regimes combining distinct levels of ultraviolet (UV) and photosynthetically active radiation (PAR). Changes in root and shoot morphology, accumulation of phenolic compounds, amino acids, and sugars were studied together with the analysis of C and N content in leaves. Both UV and PAR reduced leaf length and increased root-to-shoot ratio (R:S). Such effect was more pronounced under high N availability. High N supply reduced R:S, but this effect showed significant interactions with UV and PAR, and also with barley variety. Changes in R:S were positively related to C:N ratio in leaves that varied in response to both N availability and radiation treatments. UV radiation, particularly in combination with high PAR intensity, led to increases in most phenolic compounds (particularly flavones such as saponarin, homoorientin and isovitexin) which was also closely associated with changes in C:N ratio, while specifically phenolic acids (vanillic and syringic acids) decreased under high levels of UV and PAR, and hydroxycinnamic acids responded positively mainly to PAR. Although high N availability generally reduced the accumulation of phenolic compounds, this effect was genotype-specific and modulated by the radiation regime. A similar antagonistic effect of radiation treatment and N availability was also found for the accumulation of sugars (pentoses), resulting in a close relationship between the accumulation of pentoses and C:N ratio. The accumulation of most amino acids, in contrary to phenolic compounds, increases at high N and is also stimulated by high PAR and UV intensities. We conclude that radiation conditions and N availability have opposite effects on plant morphology and accumulation of most phenolic compounds and modulate the amino acid and sugar metabolism. Strong associations of these responses with changes in C:N ratio indicates that plant stoichiometry integrates acclimation processes and induction of relevant defence mechanisms.

Interactive effects of ultraviolet radiation and elevated CO2 concentration on photosynthetic characteristics of European beech saplings during the vegetation season

To test the hypothesis that ultraviolet radiation (UV) modulates photosynthetic responses to elevated CO₂ concentration ([CO₂]) in plants, saplings of European beech were grown for two vegetation seasons under ambient (400 ppm) and elevated (700 ppm) atmospheric [CO₂]. From April to November the saplings were exposed to (i) ambient UV radiation, (ii) excluded and (iii) enhanced UV (150% of ambient). Gas-exchange and chlorophyll fluorescence techniques were used throughout the second vegetation season together with biochemical analyses of the amount and activity of the Rubisco enzyme. We found support for the hypothesis that an impact of elevated [CO₂] on photosynthesis is substantially modulated by UV radiation. Moreover, we found that the [CO₂] × UV interaction is changing along the vegetation season: an enhanced UV radiation stimulated a positive effect of elevated [CO₂] on plant photosynthesis at the beginning of the vegetation season (short-term effect), whilst long-term cultivation reduced the stimulatory effect of elevated [CO₂] (a clear down-regulation of photosynthesis). Down-regulation was, however, not found in plants grown under the conditions of excluded UV radiation. We found evidence that the down-regulation of photosynthesis is associated with a complex acclimation at different hierarchical and functional levels, including an acclimation of primary photochemical reactions, carboxylation activity of Rubisco enzyme, and stomatal conductance.

[Aspiration of functional ovarian cyst]

OBJECTIVE

The study was designed to prove the safety of simple cyst aspiration instead of the current treatment by laparoscopy.

DESIGN

Retrospective analysis.

SETTING

Fertimed Olomouc, Infertility Center.

METHODS

We are presenting our experience with the aspiration of follicles (group A) and a functional cyst (group B, C). We are evaluating a number of complications in all groups, anaesthesia versus analgesia in group B, C and the cytological examination of fluid from the function cyst in group C.

RESULTS

In 2,744 aspirations we detected 0.0004% small complications (vaginal wall bleeding) and 0.0004% major complications (laparoscopy, cystoscopy). No single cytological examination was suspect in the simple ovarian function cyst.

CONCLUSION

Aspiration of a simple functional cyst is the first step of the treatment. It is a simple procedure. For patients it is comfortable and safe. In a simple cyst, we do not find suspect cells.

The biobanking research infrastructure BBMRI_CZ: a critical tool to enhance translational cancer research

We introduce the national research biobanking infrastructure, BBMRI_CZ. The infrastructure has been founded by the Ministry of Education and became a partner of the European biobanking infrastructure BBMRI.eu. It is designed as a network of individual biobanks where each biobank stores samples obtained from associated healthcare providers. The biobanks comprise long term storage (various types of tissues classified by diagnosis, serum at surgery, genomic DNA and RNA) and short term storage (longitudinally sampled patient sera). We discuss the operation workflow of the infrastructure that needs to be the distributed system: transfer of the samples to the biobank needs to be accompanied by extraction of data from the hospital information systems and this data must be stored in a central index serving mainly for sample lookup. Since BBMRI_CZ is designed solely for research purposes, the data is anonymised prior to their integration into the central BBMRI_CZ index. The index is then available for registered researchers to seek for samples of interest and to request the samples from biobank managers. The paper provides an overview of the structure of data stored in the index. We also discuss monitoring system for the biobanks, incorporated to ensure quality of the stored samples.

[The effect of verapamil and nifedipine on acid-base and electrolyte disorders induced by cholesterol in rabbits]

The influence of cholesterol atherogenic diet on the acid-base balance and electrolyte profile was investigated in rabbit blood and the effect of simultaneous administration of verapamil and nifedipine on the induced changes was evaluated. Cholesterol diet resulted in significant metabolic acidosis, hyperkalemia, and a slight decrease in plasma ionized calcium. On the other hand, longterm treatment with verapamil and nifedipine exhibited their protective effect, with the acid-base status and electrolyte profile maintained within the normal range. The protective effect of verapamil and nifedipine against cholesterol induced acid-base and electrolyte disturbances appears to be associated with their antiatherogenic activity. (Fig. 5, Ref. 10.).

[The effect of calcium antagonists on total calcium and magnesium levels in the aorta of rabbits after administration of dietary cholesterol]

The objective of the work was to investigate the effect of calcium blockers--dilthiazem (2 mg.kg-1.day-1), isradipine (2.5 mg.kg-1.day-1) and verapamil (0.25 mg.kg-1.day-1) on the calcium and magnesium content of the rabbit aorta with experimental atherosclerosis induced by a 1% cholesterol diet. In the aorta of rabbits kept on a cholesterol diet the calcium and magnesium content, as compared with a control group on a ordinary diet, increased significantly. In the experimental groups to whom during the eight-week period on the cholesterol diet at regular 12-hour intervals calcium antagonists were administered the calcium and magnesium content of the aorta reached normal levels. The antiatherogenic effect was, however, produced only by verapamil when administered in therapeutic doses.

[The effect of verapamil and nifedipine on the development of experimental atherosclerosis in rabbits]

The main objective of the study was to investigate the effect of the calcium antagonists Verapamil (2 mg.kg-1.day) and Nifedipine (1 mg.kg-1.day-1) on cholesterol (1%) induced atherosclerosis in rabbits. The drugs were administered s.c. twice daily over a period of 8 weeks. Blood lipid levels were determined three times during the experiment. After the experimental period the animals were killed and macroscopic changes on the aorta were recorded. For histochemical investigation samples were taken from the arch of the aorta and coronary artery. In cryostat sections lipids were determined by Sudan black B and Fett rot 7 B and the following enzymes were assayed: acid phosphatase, non-specific and acid esterase, acid beta-galactosidase, dipeptidyl peptidase I and II, and glucose-6-phosphate dehydrogenase. Following treatment with the calcium antagonists the levels of triacylglycerols and of total cholesterol were significantly increased in comparison with the control and diet groups. The ratio of HDL cholesterol to total cholesterol decreased in the treated animals. In lipoid plaques the activity of enzymes was enhanced in all experimental animals. There were however no qualitative differences in the composition of plaques between individual groups, which exhibited only quantitative differences. The number of migrating macrophages was increased only in the nifedipine treated animals. The extent of plaques was significantly decreased after nifedipine treatment, whereas verapamil failed to exert antiatherogenic effect. (Tab. 2, Fig. 4, Ref. 22.).

Acid-base balance disturbance following toxic doses of local anesthetics

The effect of equitoxic doses of three carbamate local anesthetics (pentacaine, carbisocaine and heptacaine), and a derivative of lidocaine (trimecaine) on the acid-base balance of blood was studied in conscious rabbits. In addition, changes in arterial blood pH induced by local anesthetics in relation to lipophilicity of the respective drugs were evaluated. All the drugs administered at the dose of half of LD50 induced a significant decrease in the arterial blood pH as well as in the plasma bicarbonate level and in the blood base excess. The observed acidosis was compensated within a 60 minute period by hyperventilation. The local anesthetic-induced decrease in the blood pH, expressed as AUC, correlated to some extent with the partition coefficient of these agents. These findings suggest that the acidifying effect of local anesthetics may be dependent on their lipophilicity.