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EN
Cyanobacteria constitute a rich source of biologically active and structurally diverse compounds. The pharmacological potential of these compounds resides among others in their ability to control the proliferation and growth of cancer cell lines and potent disease-causing microbial agents. Despite recent scientific advances, the way these compounds interact with the body’s molecular structure are still unclear and science still has to discover how the cyanobacterial metabolites interact with cell structures and how cells react to them. In this project, we will study yet unexamined cyanobacterial metabolites, especially the compounds which act as chemical ligands for microRNA (miRNA) -binding sites, making them promising regulators (inhibitors) of gene networks that are involved in various diseases. We will first develop a stable cell line that constitutively expresses a unique miRNA reporter system. Then, we will conduct a screen on chemical compounds discovered in Baltic cyanobacteria to identify small molecules with inhibitory activity and specificity to MIR92b-3p, which has a significant impact on liver cell behavior in humans. We assume that a successful MIR92b-3p inhibitor will bind to the precursors of MIR92b-3p miRNA, disabling the action of either of the two processing enzymes involved in the biogenesis of any miRNA in a cell (Drosha or Dicer), thus affecting the MIR92b function. The discoveries made with these inhibitory chemical molecules could provide insight into the role of the MIR92 pathway in liver diseases and cancer, and possibly, if promising results appear, they may facilitate a strategy for treating some human diseases in the future.
EN
The continued lack of knowledge concerning the molecular background of adverse effects caused by microcystin-LR (MC-LR) is surprising. This toxin requires additional attention, not only for its ability to cause acute poisoning, but also for its ability to initiate cancer in acute doses, and potentially, to promote cancer via chronic exposure to low concentrations in drinking water. Our recent studies on whitefish (Coregonus lavaretus) revealed that long-term exposure to MC-LR resulted in severe liver injury, followed by regeneration of the liver and its unexpected resilience to further toxin uptake. These effects were accompanied by perturbations of hepatic microRNAs (miRNAs) that have target genes involved in cytoskeletal remodeling, cell metabolism, cell cycle regulation, and apoptosis. Among the most pronounced individual alterations, the reduction of MiR92b-3p expression was the most remarkable, and we suggest roles for the miRNA in the aberrant processes of liver cells. This project addresses potential involvement of MiR92b-3p in the as yet unknown regulatory network of MC-induced hepatotoxicity in fish. After a suite of biochemical, physiological, anatomical, and transcriptomic analyses in vitro and in vivo, we will show how MiR92b-3p works in a damaged liver and which processes it targets. Finally, the research will confirm if and how MiR92b-3p can be targeted therapeutically. We expect it to be shown effective enough to pave a way for its use as a tool for treatment of liver damage in fish. What is more, the RNA-based silencing technique that will be used should yield exciting data for our understanding of the system-level biology of vertebrates.
EN
Monitoring of undesirable substances by the European Union indicates a presence of natural and anthropogenic pollutants in animal feed that may be of concern for the producers, as well as the veterinary services. Although the literature concerning toxicity of DDT (an insecticide widely used in the past) is extensive, less attention has been focused on the biological properties of DDE and its interactions with other contaminants. This study reports on the concentration profile of p,p’-DDE and two other ogranochlorines (p,p’-DDT, p,p’-DDD) in different tissues of immature gilts after 14, 28, and 42 days of oral exposure to p,p’-DDE alone (0.5mg·kg-1feed·day-1) and in mixture with naturally occurring mycotoxin zearalenone, ZEN (0.5+0.1mg·kg-1feed·day-1). The treatment resulted in a time-dependent accumulation of p,p’-DDE in fat-rich tissues. Although the pesticide’s concentration found in the adipose tissue exceeded the FAO/WHO maximum residue limit (5mg·kg-1 of fat), human dietary risk is little, as it requires a substantial consumption of such contaminated pork fat. Importantly, the high concentration of p,p’-DDE found in the adrenal glands suggests a threat to the animals’ health. Finally, a difference in the accumulation of p,p’-DDE was observed between the groups treated with this compound alone or in mixture with ZEN. This is most likely related to growth performance of the animals, altered by the endocrine disrupting activity of both compounds. Further research should evaluate the effects of p,p-DDE at the observed concentrations on the pigs’ health status and enable the studies of possible interactions with other environmental pollutants.
4
Content available Neurotoxicity of cyanobacterial toxins
EN
Eutrophication of marine and fresh waters can lead to excessive development of cyanobacterial blooms, which may contain strains that produce toxins. These toxins are secondary metabolites which can accumulate in the food chain and contaminate drinking water, thus posing a potential threat to the health of humans and aquatic organisms. These toxins include a variety of compounds with different mechanisms; this review focuses on the neurotoxicity of microcystin and other cyanotoxins. Although the hepatotoxic action of microcystins is commonly known, its neurotoxic effects have also been described, e.g. oxidative stress, cytoskeletal changes and changes in protein phosphatase activity. These effects have been partially explained by the discovery in the blood brain barrier of the same membrane transporters involved in microcystins hepatotoxic mechanisms. Additionally, this paper reviews other cyanotoxins that are known or suspected to target cholinergic synapses and voltage gated channels, including anatoxin a, anatoxin a(s), antillatoxins, cylindrospermopsin, homoanatoxin a, jamaicamide, kalkitoxin and saxitoxins. The neurotoxic and cytotoxic effects of the cyanotoxins discussed here are of particular interest because of their pharmacological potential. This review also discusses the potential of these compounds to serve as drugs for cancer and central nervous system failure.
EN
Identification of differentially expressed genes that could be potentially used as biomarkers of PAH exposure of common invertebrate animal (like freshwater snail) would be a valuable resource for investigators interested in toxicology and biomonitoring of aquatic environments. Therefore, the aim of this research was to investigate effects of waterborne benzo[a]pyrene (B[a]P) exposure on mRNA expression in the pond snail’s (Lymnaea stagnalis) hepatopancreatic gland. Toward this end, mature individuals of pond snail (L. stagnalis) were treated with 50µM B[a]P solution in a short 36h static exposure test. Differential Display PCR (DD-PCR) was used to generate a unique cDNA fingerprint of genes that were differentially expressed in the tissues of exposed and unexposed snails. To assess the putative identity of the isolated cDNA amplicons (ESTs), BLAST queries were performed to find similarities in their nucleotide sequence. Real-Time qPCR analysis was used to verify the DD-PCR expression profile. Finally, an additional independent exposure study, including higher dose of B[a]P (100µM), was conducted to validate the expression of selected ESTs. BLAST revealed that only 3 out of 9 isolated ESTs had meaningful information on their putative nucleotide sequence identity. The highest similarity was scored for EST-A1, identified as the transcript of UAP-like protein, found to be up-regulated after B[a]P exposure. The original expression pattern that was observed in DD-PCR step was coherent with results of the qPCR verification for 3 out of 5 analyzed ESTs. However, changes in the ESTs expression were modest and the treatment with B[a]P resulted in significant down-regulation for only 1 unidentified fragment (EST-G42, almost 2-fold; p<0.05) when compared to untreated snails. Although no significant changes were observed for EST-A1 and EST-G42 in the validation study, their expression pattern was consistent with that obtained from DD-PCR. Surprisingly, EST-C5 remained in contrast to the DD-PCR part, but it showed significant down-regulation in group of snails exposed to 100µM B[a]P (3.5-fold; p<0.05). The obtained results show that diverse genes may be involved in the molecular response of the pond snail’s hepatopancreas to treatment with B[a]P. However, further research is needed to confirm the utility of the discovered EST as PAH biomarkers in biomonitoring practices with L. stagnalis as bioindicator species.
6
EN
The authors aim at drawing the attention oof tourist not only to the history and architecture of St. Anne's collegiate church in Kraków, one of the most beautiful Baroque structures in Poland. The particular aspect they focus on reefers to the decorative valour of the stones, which in large numbers and an attractive manner have been used inside and outside the church. As an addition to the description of the rock types and their varieties used, the places of quarrying the respective stones have been indicated for those interested in geology.
PL
Celem niniejszego artykułu jest zainteresowanie turystów historią i architekturą najpiękniejszej budowli barokowej w Polsce, którą jest kolegiata św. Anny w Krakowie. W sposób szczególny zwrócono uwagę na walory dekoracyjne kamieni, które licznie i ciekawie zostały w niej zastosowane. Przedstawiono różne rodzaje i odmiany skał występujące wewnątrz i na zewnątrz tej budowli sakralnej. Dla zainteresowanych geologią wskazano miejsca pochodzenia materiału kamiennego.
PL
W artykule została przedstawiona metodyka testowania oprogramowania złożonych zintegrowanych systemów monitorowania i sterowania. Przedstawiono przykład wykorzystania proponowanej metodyki podczas procesu testowania oprogramowania zintegrowanego systemu monitorowania i sterowania państwowego wzorca jednostek miar czasu i częstotliwości (PWJMCiC).
EN
In the paper, software testing process of an integrated system for monitoring and control of national unit standard time and frequency systems (PWJMCiC) based on the assumed methodology is presented. There is also described the methodology procedure developed for implementation of complex control-measuring systems. In the introduction there are shown examples proving the fact that the waterfall model (Fig.1), used most frequently for design of simple, uncomplicated measurement systems, has drawbacks. They make its application to the complex integrated systems for monitoring and control impossible. Next, there is presented a methodology WU-CMD (Waterfall User-Centered Design Model) developed by the author. It combines elements of methodology for User-Centered Design [3] and elements of the waterfall model [4]. The proposed methodology assumes that the assumptions for a measurement system are formed on the basis of analysis of future user's needs, and the future user of the measurement system participates at all stages of its design, through reporting comments and accepting changes. Each stage of the design is time-bound and documented in detail, for each of the stages there are specified requirements that must be met to make it possible to finish the stage. It is also assumed that at each stage there are carried out tests of compliance, accuracy and consistency of implementation of individual elements (as well as the whole) of the designed measurement system.
PL
W artykule została przedstawiona metoda wyznaczania liczby testów na podstawie znajomości liczby elementów interfejsu użytkownika przyrządu wirtualnego. Powiązano liczbę przypadków testowych z ogólną liczbą przeprowadzonych testów, gdy testy przeprowadzane są dla kombinacji elementów interfejsu użytkownika przyrządu wirtualnego. Przedstawiono też sposób określania czasu przeprowadzenia testów na podstawie znajomości liczby przypadków testowych.
EN
In his paper presented is the method of test cases calculation on the basis of number of user interface elements of virtual instrument. The number of test cases was related to overall number of carried out tests, when the test are carried out for combination of user interface elements. The manner of determining time for the tests was presented. That was done on the basis of knowledge of number of test cases.
9
Content available remote Budowa i testowanie interfejsu użytkownika przyrządu pomiarowego
PL
W artykule został przedstawiony przegląd metod budowy i testowania wybranych typów interfejsu użytkownika przyrządów pomiarowych, ze szczególnym uwzględnieniem przyrządów wirtualnych. Na podstawie przeglądu 22 artykułów o przyrządach wirtualnych, zaproponowano sposób rozmieszczenia poszczególnych typów elementów interfejsu użytkownika.
EN
In this paper, review of various methods constructing and testing chosen types of user interface was presented. On the basis of review 22 papers about virtual instrumentation, unified manner of placement particular types of elements of user interface was proposed.
10
Content available remote Testowanie oprogramowania wirtualnego przyrządu pomiarowego
PL
W wirtualnych przyrządach pomiarowych składających się z części programowej i sprzętowej, część programowa obejmuje program znajdujący się w komputerze i oprogramowanie zaimplementowane w sprzęcie. Przeprowadzenie testów takiego przyrządu jest trudne, bo trudno określić założenia, tak by testy były kompleksowe i obejmowały wszystkie najistotniejsze elementy przyrządu. Model wirtualnego przyrządu pomiarowego można stworzyć na podstawie zbioru parametrów opisujących część programową i sprzętową oraz powiązania pomiędzy nimi (zwykle interfejs komunikacyjny). Na podstawie takiego modelu można przeprowadzać kompleksowe testy części programowej wirtualnego przyrządu pomiarowego oraz analizować uzyskane wyniki, co zostanie przedstawione w artykule.
EN
The methods of VI software testing are very complicated. Virtual Instruments are build form software and hardware part. The software consist of GUI part and software part, that is implemented in hardware. New parametric method, presented in this article, allow to do complete functional Virtual Instrument software tests.
PL
W artykule przedstawiono wybrane metody testowania aplikacji informatycznych oraz praktyczny sposób ich wykorzystania do testowania wirtualnych przyrządów pomiarowych. Przedstawiono też zagadnienia związane z procesem testowania wirtualnego przyrządu na tle procesu jego wytwarzania.
EN
In article one introduced selected methods of IT application testing and practical manner of their utilisation in testing of virtual measuring instruments. Introduced problems are connected with process of virtual instrument testing on background of process his productions.
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