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Hana Michalkova,1 Vladislav Strmiska,1 Jiri Kudr,1,2 Zuzana Skubalova,1 Barbora Tesarova,1 Pavel Svec,1 Lukas Richtera,1,2 Ondrej Zitka,1,2 Vojtech Adam,1,2 Zbynek Heger1,2 1Department of Chemistry and Biochemistry, Mendel University in Brno, Brno CZ-613 00, Czech Republic; 2Smart Nanodevices Research Group, Central European Institute of Technology, Brno University of Technology, Brno CZ-621 00, Czech RepublicCorrespondence: Zbynek HegerDepartment of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, Brno CZ-613 00, Czech RepublicTel +420 54 513 3350Fax +420 54 521 2044Email heger@mendelu.czBackground: Iron oxide nanoparticles (IONs) have been increasingly utilized in a wide spectrum of biomedical applications. Surface coatings of IONs can bestow a number of exceptional properties, including enhanced stability of IONs, increased loading of drugs or their controlled release.Methods: Using two-step sonochemical protocol, IONs were surface-coated with polyoxyethylene stearate, polyvinylpyrrolidone or chitosan for a loading of two distinct topo II poisons (doxorubicin and ellipticine). The cytotoxic behavior was tested in vitro against breast cancer (MDA-MB-231) and healthy epithelial cells (HEK-293 and HBL-100). In addition, biocompatibility studies (hemotoxicity, protein corona formation, binding of third complement component) were performed.Results: Notably, despite surface-coated IONs exhibited only negligible cytotoxicity, upon tethering with topo II poisons, synergistic or additional enhancement of cytotoxicity was found in MDA-MB-231 cells. Pronounced anti-migratory activity, DNA fragmentation, decrease in expression of procaspase-3 and enhancement of p53 expression were further identified upon exposure to surface-coated IONs with tethered doxorubicin and ellipticine. Moreover, surface-coated IONs nanoformulations of topo II poisons exhibited exceptional stability in human plasma with no protein corona and complement 3 binding, and only a mild induction of hemolysis in human red blood cells.Conclusion: The results imply a high potential of an efficient ultrasound-mediated surface functionalization of IONs as delivery vehicles to improve therapeutic efficiency of topo II poisons.Keywords: doxorubicin, ellipticine, iron oxide, nanoparticles, release kinetics

Michalkova H, Strmiska V, Kudr J, et al. Int J Nanomedicine. 2019;14:7609–7624The authors have advised due to an error at the time of figure assembly, Figure 1D on page 7614 and Figure 6A on page 7621 is incorrect. Read the original article

Biological processes tend to dominate the oxygen regime of productive waters. However, in shallow aquatic ecosystems, it is unclear whether the oxygen regime is driven by oxygen production and consumption in the water column or by sediment oxygen demand (SOD). In managed eutrophic ecosystems, this question is especially important in the context of extreme daily oscillations of dissolved oxygen (DO) that could breach physiological limits of heterotrophic aerobic organisms. High-frequency measurement of DO, temperature, global radiation (Gl.Rad.), and pH in a 0.6 m deep, 22 ha eutrophic fishpond Rod (Czech Republic) shows that the oxygen regime depended on the ecosystem state. Over the clearwater period in the early season, the DO level reflected ecosystem heterotrophy with relatively low daily DO oscillations. However, during the summer phytoplankton bloom, the fishpond was primarily autotrophic with extreme DO fluctuation. During late summer, a collapse of the phytoplankton bloom and an associated shift towards heterotrophy and DO deficit frequently occur. In-situ mesocosm experiments in Rod fishpond were conducted throughout 2018 and 2019 growing seasons, to address the importance of SOD to the oxygen regime. We enclosed the water column in transparent and opaque/dark plastic cylinders open or closed to the sediment. The results show that the proportional contribution of SOD to total respiration decreased from 70 to 90% at low phytoplankton biomass (expressed as Chlorophyll-a (Chl-a) concentration) to approximately 10% at phytoplankton bloom. At night, the difference between the oxygen consumption in the cylinders with or without sediment was statistically significant, when the concentration of Chl-a was <100 μg·L -1 . On the contrary, the difference was not significant when the concentration of Chl-a was >100 μg·L -1 . This revealed that the impact of SOD is negligible at high phytoplankton biomass., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personaI relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Man-made shallow fishponds in the Czech Republic have been facing high eutrophication since the 1950s. Anthropogenic eutrophication and feeding of fish have strongly affected the physicochemical properties of water and its aquatic community composition, leading to harmful algal bloom formation. In our current study, we characterized the phytoplankton community across three eutrophic ponds to assess the phytoplankton dynamics during the vegetation season. We microscopically identified and quantified 29 cyanobacterial taxa comprising non-toxigenic and toxigenic species. Further, a detailed cyanopeptides (CNPs) profiling was performed using molecular networking analysis of liquid chromatography-tandem mass spectrometry (LC-MS/MS) data coupled with a dereplication strategy. This MS networking approach, coupled with dereplication, on the online global natural product social networking (GNPS) web platform led us to putatively identify forty CNPs: fourteen anabaenopeptins, ten microcystins, five cyanopeptolins, six microginins, two cyanobactins, a dipeptide radiosumin, a cyclooctapeptide planktocyclin, and epidolastatin 12. We applied the binary logistic regression to estimate the CNPs producers by correlating the GNPS data with the species abundance. The usage of the GNPS web platform proved a valuable approach for the rapid and simultaneous detection of a large number of peptides and rapid risk assessments for harmful blooms.

Objective: To evaluate the incidence of neonatal morbidity (NM), and developmental impairments (DIs) of very low (VLBW) and extremely low birth weight (ELBW) infants born in 2000-2009., Design: Epidemiological study., Setting: Outpatient clinics for children with perinatal risk at the regional neonatal centers., Methods: Data on live born, specific neonatal mortality (SNM) and NM data were taken from the database the database of Institute of Health Information and Statistics of Czech Republic (IHIS CR). The incidence of DIs (cerebral palsy - CP, developmental delay - DD, growth retardation and sensory impairment) was evaluated at 24 months corrected age. Each cohort included newborn infants born always in the two-year periods.. Comparison of the incidence of DIs according to the birth-weight or to gestational age was performed in children born in 2009., Results: 1. NM - in VLBW newborns, CNS morbidity and early indecisions decreased slightly (i.e. by 7 and 5%), other forms remained unchanged. In ELBW infants, CNS morbidity declined by 13.9% (p<0.05), early infections only by 5% (NS). - 2. DIs: - in VLBW infants, cerebral morbidity and early infections were reduced slightly (i.e. by 7 and 5% resp.). In ELBW category, CP decreased by 12%, and visual impairment by 9% (p<0.05). - 3. The occurrence of DIs by birth weight or gestational age did not differ, only in children <1000 g, in comparison with the group of <28 wks, was delayed growth increased by 6% (NS). - 4. In 2000-2007, SNM rate and also number of disabled children declined continuously. During period 2008-2009, in contrast to the previous 8 years, incidence of impaired children in both categories increased slightly (by 3%, and 1%, resp., NS)., Conclusion: During the study period, SNM declined continuously, especially in the ELBW category. We managed to partially reduce NM (CNS and early infection), the problem remained late infection. In the period 2000-2007, incidence of DIs decreased, significantly in case of CP and visual impairment in ELBW children. Surprisingly in the last two years 2008-2009, there appeared in both categories an increase in the proportion of children with disabilities. It is a worrying finding, which should be re-evaluated.