Band 9, Heft 11

The effects of growth retardants (paclobutrazol and ancymidol), sucrose, GA3 (gibberellic acid) and physical state of the medium (solid and liquid — Rita® temporary immersion system) on in vitro induction of Leucojum aestivum bulbs and their acclimatization were studied. Paclobutrazol, regardless of the physical state of the medium, stimulated the formation of bulbs (99.3%). Under the influence 90 g L−1 of sucrose or paclobutrazol the bulbs with the highest fresh weight (FW) were formed (250 mg and 208.8 mg, respectively). However, the addition of ancymidol to the liquid medium led to obtaining the bulbs showing the highest number of leaves and roots (63.2% and 91.7%, respectively). The scanning microscopy study proved that plants obtained in the medium containing GA3 produced the stomata which most closely resembled to the one observed in the mother plant. Cytometric analysis of all regenerants revealed absence of changes in the nuclear DNA content. The maximum survival rate (100%) was observed for plants derived from liquid medium containing 90 g L−1 of sucrose. Somewhat fewer plants were acclimatized after their cultivations in liquid medium enriched with paclobutrazol or ancymidol. The temporary immersion system led to perform successful ex vitro adaptation of Leucojum aestivum plants.

Colitis-associated colorectal cancer (CACRC) constitutes a severe complication of inflammatory bowel diseases (IBD) and occurs in more than one third of IBD patients. In this short review we focus on the mechanisms underlying CACRC pathogenesis, and discuss the approaches for prevention and therapy in CACRC.

PGC-1α has been implicated as an important mediator of functional capacity of skeletal muscle. However, the role of PGC-1α in myoblast differentiation remains unexplored. In the present study, we observed a significant up-regulation of PGC-1α expression during the differentiation of murine C2C12 myoblast. To understand the biological significance of PGC-1α up-regulation in myoblast differentiation, C2C12 cells were transfected with murine PGC-1α cDNA and siRNA targeting PGC-1α, respectively. PGC-1α over-expressing clones fused to form typical myotubes with higher mRNA level of myosin heavy chain isoform I (MyHCI) and lower MyHCIIX. No obvious differentiation was observed in PGC-1α-targeted siRNA-transfected cells with marked decrement of mRNA levels of MyHCI and MyHCIIX. Furthermore, PGC-1α increased the expression of MyoD and MyoG in C2C12 cells, which controlled the commitment of precursor cells to myotubes. These results indicate that PGC-1α is associated with myoblast differentiation and elevates MyoD and MyoG expression levels in C2C12 cells.

The aim of this study was to make a comparative analysis of macrozoobenthos composition at different sites at selected sections of lower the Odra River with relation to different physicochemical factors. The observations were made on the lower section of Odra River at five study sites: two of them were localized in the main channel, one in the left branch of river, another one in the channel carrying post-cooling water from Dolna Odra power plant, and the last one was in the channel connecting both branches of Odra River. At all sites, 26 taxa were found representing by: Bivalvia, Gastropoda, Oligochaeta, Hirudinea, Malacostraca and Insecta. The greatest biodiversity and the highest abundance of zoobenthos organisms were noted in the channel joining the two branches of the river, site 5, characterised by the lowest water flow rates and the densest coverage of the macrophytes at the bottom. Temperature was the sole parameter to be studied that affected the composition of benthic invertebrates. A clearly negative impact of temperature on the diversity of invertebrates was observed only in the channel with post-cooling water discharged from the power plant.

The effects of benzo(a)pyrene (Bap) (0.03, 0.3 and 3 μg L−1) and chrysene (CHR) (0.3, 2.1 and 14.7 μg L−1) on the function of the immune system of juvenile white shrimp Litopenaeus vannamei were determined under laboratory conditions. This included the total hemocyte count (THC) in the hemolymph, phagocytic activityand pro-phenoloxidase (pro-PO) activity of the hemocyte, phenoloxidase (PO) activity, α2-macroglobulin (α2-M) activity, bacteriolytic activity and antibacterial activity in the hemolymph. The results showed that BaP and CHR could inhibit the immune function of L. vannamei significantly under high concentration BaP and CHR exposure. The results of this study indicated that the immunotoxicity of PAHs in a descending order was BaP>CHR. Moreover, the results indicated the THC in hemolymph, pro-PO activity and phagocytic activity of hemocyte, and bacteriolytic activity in hemolymphcould be used as potentially suitable biomarkersfor early warning indication of PAHs toxicity, this could provide useful information for toxic risk assessment of environmental pollutants.

Silver nanoparticles (AgNPs) have cytotoxic properties via generation of reactive oxygen species which are involved in the generalized sickness behavior of the host, including fever and lethargy among others. The aim of the present study was to investigate the impact of AgNPs on the ability of rat peripheral blood mononuclear cells (PBMCs) to release fever mediating factors after stimulation with lipopolysaccharide (LPS). Body temperature and motor activity of the Wistar rats were measured by biotelemetry system. Rat PBMCs were stimulated with LPS and after that the cells were washed and incubated alone or with AgNPs. The final supernatants were injected intraperitoneally. The levels of endogenous pyrogens such as interleukin-1β (IL−1β), IL-6 and tumor necrosis factor-α (TNF-α) released from the PBMCs into the final supernatants were also estimated. The results indicated that injection of the supernatants from the cells stimulated with LPS induced fever and inhibited motor activity. These effects were potentiated by the presence of AgNPs during the final incubation. The presence of the AgNPs also resulted in significant increases in levels of endogenous pyrogens. The augmentation of fever in the rats by the AgNPs treatment of the cultures seemed to be primarily associated with the changes in interleukin-1β levels.

Effects of water salinity (3.0–9.0 PSU) on the duration and outcome of embryogenesis in the lesser sandeel (Ammodytes tobianus (L.) as well as on survival, size, and malformation rate of the newly hatched larvae were followed, based on observations involving equipment consisting of a microscope and still and digital cameras. The images obtained and measurements of egg and larval dimensions were analyzed using the NIS elements Br. computer software package. The lowest salinity tested (3.0 PSU), similar to that in the inshore Baltic Sea waters native for the species studied, produced a lower fertilization rate and resulted in extended embryogenesis, reduced embryo survival, changes in the hatch size, and increased larval malformation rate. The high-end salinity (7.5–9.0 PSU), higher than that prevailing in the species’s spawning grounds in the Baltic Sea, resulted — similarly to the low-end salinity — in disturbed development and growth of the embryos.

Sweet rowanberries originated by the crossbreeding of wild rowanberries with other fruit species such as apples, medlars or black chokeberries. They are highly resistant to cold climate. In contrast with wild rowanberries, they have sweet mild taste and show less parasorbic acid toxicity, which can be eliminated, when the consumption is excessive, by heating. The objective of the work was to determine selected antioxidant properties in 6 cultivars. The analyses showed that the contents of total phenolics, total flavonoids and ascorbic acid were high. Similarly, antioxidant capacity (6.58–9.62 g of ascorbic acid equivalents kg−1) was also high. The work brings novel data, in particular, when comparing the cultivars; moreover, results regarding reactive oxygen and nitrogen species scavenging activity in sweet rowanberries are being published for the first time. The sweet rowanberry extracts (10%) showed inhibitory ability on hydroxyl radical (16.12–24.73%), superoxide anion (26.74–34.02%), nitric oxide (24.75–31.39%), and lipid peroxidation (7.93–13.12%). The values obtained are even many times higher than those found in common commercial fruit species like apples. Therefore, sweet rowanberries appear to be a promising fruit species for human nutrition, especially due to their high content of bioactive substances and ease of cultivation in worse climatic and soil conditions.

We evaluated the response of eight economically important Croatian grapevine cultivars and studied the impact of their sanitary status on in vitro introduction, by comparing the response of healthy and virus-infected genotypes of one cultivar. Nodal explant survival on three media, M1 (half-strength MS), M2 (full-strength MS) or M3 (full-strength MS with 4.4 µM L−1 benzylaminopurine) was measured after 2 weeks and regrowth after 8 weeks. After 8 weeks, average shoot length and node number were significantly higher on M2 compared to M1 and M3. M3 induced significantly shorter average internode length, compared to M1 and M2. Survival of one healthy and of five cultivar Plavac mali genotypes infected with GFLV, GLRaV-1, GLRaV-3, GLRaV-3+GVA and GLRaV-1+GLRaV-3 was 97.5 and 82.8–87.5%, respectively. Regrowth of the healthy genotype reached 95.5%, but dropped to 5.5–31.4% in infected ones. The healthy genotype showed significantly higher shoot length (6.3 cm) and node number (7.3) compared to infected genotypes, with shoot length between 1.2–2.6 cm and node number between 1.2–3.0. By contrast, internode length was not significantly different between the healthy and the infected genotypes. The present work represents the first successful in vitro introduction for three of the eight native Croatian cultivars studied.

This study was aimed to investigate the possibility of regulating free proline content and ethylene production in the resistant to abiotic stress cv. ‘Hornet H’ and the tolerant to stress cv. ‘Sunday’ of winter rapeseed seedlings by pretreatment with exogenous L-proline and L-glutamine in non-acclimated and cold-acclimated seedlings in relation to freezing tolerance. The ratio of proline content in acclimated (at 4°C) versus non-acclimated (18°C) ‘Hornet H’ seedlings increased 2.12-fold and in ‘Sunday’ seedlings 1.95-fold. Exogenously applied, proline and glutamine produced a positive effect on free proline content in both cold-acclimated and non-acclimated seedlings. At a temperature of -1°C the proline content significantly increased in non-acclimated and especially in cold-acclimated seedlings. At an intensified freezing temperature (−3°C, −5°C, −7°C), the proline content decreased in comparison with that at −1°C, but glutamine, especially proline, in cold-acclimated seedlings takes part in free proline level increase and in seedlings’ resistance to freezing. Ethylene production increased in cold-acclimated conditions and under the effect of exogenous proline and glutamine. In freezing conditions, ethylene production decreased, but in cold-acclimated seedlings and under pretreatment of proline and glutamine the ethylene synthesis was intensive. Thus, free proline content and ethylene production increase in cold-acclimated winter rapeseed seedlings and under pretreatment with glutamine and especially with proline. Free proline is involved in the response to cold stress, and its level may be an indicator of cold-hardening and freezing tolerance, but the role of ethylene in the regulation of cold tolerance remains not quite clear.

Plant-derived smoke water (SW), derived from combusted plant material, has been shown to stimulate seed germination and improve seedling vigor of a number of plant species from fire-dependent Mediterranean-type climate areas. The effects of SW on seed germination of 13 plant species from southern tropical and subtropical monsoon climate regions of South China are reported for the first time in this study using laboratory and pot trials. Among the 13 species tested, only Aristolochia debilis showed a significant positive response to commercial SW when diluted 1:10. Seed germination of A. debilis was also stimulated by 1–100 nM 3-methyl-2H-furo [2, 3-c] pyran-2-one (karrikin 1 or KAR1) and by 10–1000 µM gibberellic acid (GA3). GA3 stimulated seed germination of Santalum album and significantly elongated the radicles of A. debilis while SW could not. The functions and/or metabolic pathways of Kar1 and GA3 are likely to be separate and/or distinct.

The impact of melatonin (50 µM L−1) applied to Vigna radiata seeds by hydro-priming on phenolic content, L-phenylalanine ammonialyase (PAL) activity, MEL level, antioxidant properties of ethanol extracts as well as electrolyte leakage from chilled and re-warmed Vigna radiata roots of seedlings were examined. Seedlings obtained from non-primed seeds, hydro-primed and hydro-primed with MEL were investigated after 2 days of chilling and 2 days of re-warming. At 25°C, the level of MEL in roots derived from seeds hydro-primed with MEL was 7-fold higher than in roots derived from non-primed seeds. However, the content of MEL significantly decreased in all variants investigated after re-warming, in contrast to PAL activity and phenolic levels, which reached the highest values. The antioxidant capacity of ethanol extracts from chilled and re-warmed roots, determined by ABTS+· assay, was correlated with phenolic content while the reducing ability of these extracts, determined by the FRAP method, correlated with PAL activity. However, both were the highest in rewarmed roots with applied MEL, which was accompanied by a significant decline in electrolyte leakage. Taken together, results may indicate that MEL can play a positive role in plant acclimation to stressful conditions and activation of phenolic pathway by this molecule.