Charles University in Prague

About: Charles University in Prague is a education organization based out in Prague, Czechia. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 32392 authors who have published 74435 publications receiving 1804208 citations.

Preanalytical quality improvement: from dream to reality

Abstract: Laboratory diagnostics (i.e., the total testing process) develops conventionally through a virtual loop, originally referred to as "the brain to brain cycle" by George Lundberg. Throughout this complex cycle, there is an inherent possibility that a mistake might occur. According to reliable data, preanalytical errors still account for nearly 60%-70% of all problems occurring in laboratory diagnostics, most of them attributable to mishandling procedures during collection, handling, preparing or storing the specimens. Although most of these would be "intercepted" before inappropriate reactions are taken, in nearly one fifth of the cases they can produce inappropriate investigations and unjustifiable increase in costs, while generating inappropriate clinical decisions and causing some unfortunate circumstances. Several steps have already been undertaken to increase awareness and establish a governance of this frequently overlooked aspect of the total testing process. Standardization and monitoring preanalytical variables is of foremost importance and is associated with the most efficient and well-organized laboratories, resulting in reduced operational costs and increased revenues. As such, this article is aimed at providing readers with significant updates on the total quality management of the preanalytical phase to endeavour further improvement for patient safety throughout this phase of the total testing process.

Continental-wide distribution of crayfish species in Europe: update and maps

Abstract: Recently published astacological studies substantially improved available data on distribution of crayfish in various European regions. At the same time, spread of invasive species has been recorded, additional non-indigenous species became established in various countries, and losses of populations of native species due to crayfish plague and other negative factors were observed. We overview recent advances in this knowledge, and provide updated colour maps of the distribution of all crayfish species present in Europe. These maps are originally based on the data from the Atlas of Crayfish in Europe published in 2006 as a result of the CRAYNET project, and were further updated from more recently published reports, grey literature, and especially thanks to contributions and feedback of over 70 specialists from 32 countries. Separate maps are available for all indigenous crayfish species in Europe as well as for three most widespread non-indigenous crayfish species. Additionally, two maps give locations of known findings of crayfish species introduced to Europe after 1980. These newly established alien species have so far restricted distributions; however, the frequency of recent reports suggests that findings of such species resulting from releases of aquarium pets will further increase.

Sudan I Is a Potential Carcinogen for Humans Evidence for Its Metabolic Activation and Detoxication by Human Recombinant Cytochrome P450 1A1 and Liver Microsomes

Abstract: 1-Phenylazo-2-hydroxynaphthol (Sudan I, C.I. Solvent Yellow 14) is a liver and urinary bladder carcinogen in mammals. We compared the ability of hepatic microsomal samples from different species including human to metabolize Sudan I. Comparison between experimental animals and human cytochromes P450 (CYP) is essential for the extrapolation of animal carcinogenicity data to assess human health risk. Human microsomes generated the pattern of Sudan I metabolites reproducing that formed by hepatic microsomes of rats. Using hepatic microsomes of rats pretreated with specific CYP inducers, microsomes from Baculovirus-transfected insect cells expressing recombinant human CYP enzymes, purified CYP enzymes, and selective CYP inhibitors, we found that rat CYP1A1 and recombinant human CYP1A1 are the most efficient enzymes metabolizing Sudan I. Microsomes from livers (the target of Sudan I carcinogenicity) of different human donors were used to estimate whether authentic human CYPs oxidize Sudan I. Using Western blot analysis and NH(2)-terminal sequencing, we were able to detect and quantify CYP1A1 in human hepatic microsomes. The sequence of nine amino acids of the protein band cross-reacting with antirat CYP1A1 in human microsomes, LFPISMSAT, matched the sequence of human CYP1A1 perfectly (residues 2-10). CYP1A1 expression levels varied significantly among the different human microsomes (0.04-2.4 pmol/mg protein), and constituted <0.6% of the total hepatic CYP complement. All of the human hepatic microsomal samples oxidized Sudan I to C-hydroxymetabolites. Moreover, using the nuclease P1-enhanced version of the (32)P-postlabeling assay, we found that human microsomes were competent in activating Sudan I to form adducts with DNA. The role of specific CYP enzymes in the human hepatic microsomal metabolism was investigated by correlating the CYP-catalytic activities (or CYP contents) in each microsomal sample with the levels of individual metabolites and/or Sudan I-DNA adducts formed by the same microsomes, and by examining the effects of agents that can inhibit specific CYP in Sudan I metabolism. On the basis of these studies, we attribute most of Sudan I metabolism in human microsomes to CYP1A1, but participation of CYP3A4 cannot be ruled out. These results, the first report on the metabolism of Sudan I by human CYP enzymes, strongly suggest a carcinogenic potency of this rodent carcinogen for humans.

Improved measurement of electron antineutrino disappearance at Daya Bay

Abstract: With 2.5× the previously reported exposure, the Daya Bay experiment has improved the measurement of the neutrino mixing parameter sin^2 2θ_(13) = 0.089 ± 0.010(stat) ± 0.005(syst). Reactor anti-neutrinos were produced by six 2.9 GW_(th) commercial power reactors, and measured by six 20-ton target-mass detectors of identical design. A total of 234,217 anti-neutrino candidates were detected in 127 days of exposure. An anti-neutrino rate of 0.944±0.007(stat)±0.003(syst) was measured by three detectors at a flux-weighted average distance of 1648 m from the reactors, relative to two detectors at 470 m and one detector at 576 m. Detector design and depth underground limited the background to 5 ± 0.3% (far detectors) and 2 ± 0.2% (near detectors) of the candidate signals. The improved precision confirms the initial measurement of reactor anti-neutrino disappearance, and continues to be the most precise measurement of θ_(13).