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[en] Our understanding of the role of Ca(2+) in blue/UV-A photoreceptor signaling in a single cell is limited. Insight into calcium signaling has now been attained in Physcomitrella patens and its cryptochrome and phototropin knock-outs. Physcomitrella patens caulonemal filaments grow in the dark by apical extension and their apical cells are highly polarized. Fura-2-dextran ratio images of the apical cell from wild type (WT), Ppcry1a/1b and PpphotA2/B1/B2 were obtained immediately following UV-A exposure (30 mu W cm(-2) at 340 nm for 1,000 ms plus 30 mu W cm(-2) at 380 nm for 1,000 ms) [abbreviated as 1,000 ms (340/ 380 nm)] and demonstrated two intracellular waves: a Ca(2+) wave from the growing apical tip through the apical cap, and a wave from the junction of the neighboring cell through the vacuolar, nuclear and plastid regions. In WT, the UV-A-induced tip wave increase had a magnitude of 454.0 +- 40 nM, traveled at a rate of 3.4 +- 0.7 mu m s(-1) and was complete within 26.6 +- 2.3 s, while the basal vacuolar wave had a magnitude of 596.8 +- 110 nM, a rate of 8.4 +- 0.8 mu m s(-1) and duration of 25.3 +- 4.9 s. Subsequent Ca(2+) spikes of similar magnitude followed these waves. The amplitude of the Ca(2+) waves in the apical cap and basal vacuolar regions of Ppcry1a/1b were higher than those in the WT, while the duration of those in PpphotA2/B1/B2 was longer. Subsequent Ca(2+) spikes occurred in WT and Ppcry1a/1b but not in PpphotA2/B1/B2. When Mn(2+) was added to the culture medium, the [Ca(2+)]cyt increase was delayed, did not move as a wave and lasted longer. The results indicate that plants respond to blue light and UV-A radiation by generating a wave of changes in the [Ca(2+)]cyt. The characteristics of these Ca(2+) waves were dependent upon cryptochrome and phototropin. Blue/UV-A signaling in P patens appears to differ from that in Arabidopsis
[en] This report described sampling, culturing and identifying of KURT underground bacteria, which existed as iron-, manganese-, and sulfate-reducing bacteria. The methods of culturing and media preparation were different by bacteria species affecting bacteria growth-rates. It will be possible for the cultured bacteria to be used for various applied experiments and researches in the future
[en] Popular culture refers to the entirety of ideas, perspectives, attitudes, behaviours, ways of communication, cultural and artistic products, (visual, auditory, written, etc.) as well as other phenomena in the real or virtual world within mainstream culture. Heavily influenced by mass media, this collection of ideas permeates the everyday lives of society. In the so-called atomic age, which corresponds to the cold war period, stylistic coloration and application of the concepts of radiation that have persisted in everyday life to this day can be classified into four main groups of radiological-nuclear themes: monsters and mutants associated with radiation, nuclear accidents, nuclear terrorism and nuclear optimism. This paper discusses some examples relating to radioactivity, radiation and nuclear topics in Croatian popular culture, with special reference to the mass media, including some Internet portals. In Croatian mass media, like in other cultures, radiation and nuclear metaphors symbolize something scary and completely incomprehensible. However, further systematic research would be needed to analyse and explain all of the stereotypes in more detail. Results would be useful in creating a more effective way for informing the general public about the effects and use of radiation and nuclear technology, which is expected to play a far greater role in solving numerous problems dealing with energy supply, medicine, etc. in the near future. It should be noted that nowadays the collective public fears shift from radiation to other global threats such as climate change, genetically modified organisms, global terrorism and others. (author).
[en] The objective this study was to determine the effect of phytohemagglutinin (PHA) on survival, growth and gene expression in caprine secondary follicles cultured in vitro. Secondary follicles (∼0.2 mm) were isolated from the cortex of caprine ovaries and cultured individually for 6 days in α-MEM"+ supplemented with PHA (0, 1, 10, 50, 100, or 200 µg/mL). After 6 days of culture, follicle diameter and survival, antrum formation, ultrastructure and expression of mRNA for FSH receptors (FSH-R), proliferating cell nuclear antigen (PCNA), and neuronal nitric oxide synthase were determined. All treatments maintained follicular survival [α-MEM"+ (94.59%); 1 µg/mL PHA (96.43%); 10 µg/mL PHA (84.85%); 50 µg/mL PHA (85.29%); 100 µg/mL PHA (88.57%), and 200 µg/mL PHA (87.50)], but the presence of 10 µg/mL PHA in the culture medium increased the antrum formation rate (21.21%) when compared with control (5.41%, P < 0.05) and ensured the maintenance of oocyte and granulosa cell ultrastructures after 6 days of culture. The expression of mRNA for FSH-R (2.7 ± 0.1) and PCNA (4.4 ± 0.2) was also significantly increased in follicles cultured with 10 µg/mL PHA in relation to those cultured in α-MEM"+ (1.0 ± 0.1). In conclusion, supplementation of culture medium with 10 µg/mL PHA maintains the follicular viability and ultrastructure, and promotes the formation of antral cavity after 6 days of culture in vitro
[en] Transdifferentiation of vascular smooth muscle cells (VSMC) promotes the development of vascular calcifications such as arteriosclerosis. The aim was to investigate effects of specific extracellular matrix (ECM) components on transdifferentiation of VSMC to identify novel ECM-based therapeutic tools. Human collagens I & IV (CI, CIV) along with collagen XIV (CXIV) and a CXIV-derived fragment (CXIV-F), both of which induce differentiation, were applied in an in-vitro model of calcium-/phosphate (Ca/P)-induced osteochondrocytic transdifferentiation of human and murine VSMC. Transdifferentiation was determined by RT-PCR and calcium contents of VSMC cultures. Signaling pathways involved were determined by western-blot and luciferase reporter plasmid assays. Under normal culture conditions, CI induced VSMC proliferation and a more epithelioid/synthetic phenotype while CIV and predominantly CXIV provoked opposite effects. CIV and CXIV further blocked Ca/P-induced osteochondrocytic transdifferentiation of VSMC displayed e.g. by reduced gene expressions of Runx2, Sox9, osterix and increased expressions of αSMA and SM22α. This involved impaired activation of ERK1/2, NF-ĸB and Wnt-signaling. Similar preventive effects were achieved by applying CXIV-F. Impaired preventive effects of CXIV by co-treatment with a cluster of differentiation (CD)44 agonist propose CD44 as a CXIV-target structure on VSMC. In conclusion, CXIV and CXIV-F interfere with osteochondrocytic transdifferentiation of VSMC and should be further explored as potential therapeutic tools in vascular calcification. - Highlights: • Collagen XIV maintains a quiescent contractile VSMC phenotype. • Collagen XIV blocks mineral-induced osteochondrocytic VSMC transdifferentiation. • Similar preventive effects were observed for a Collagen XIV-derived fragment. • Collagen XIV reduces activation of ERK1/2, NF-ĸB- and Wnt-signaling in VSMC. • Data point to CD44 as a target structure of collagen XIV on VSMC.