Cu exposure under field conditions coselects for antibiotic resistance as determined by a novel cultivation-independent bacterial community tolerance assay

Environmental reservoirs of antibiotic resistance are important to human health, and recent evidence indicates that terrestrial resistance reservoirs have expanded during the antibiotic era. Our aim was to study the impact of Cu pollution as a selective driver for the spread of antibiotic resistance in soil. Bacteria were extracted from a well-characterized soil site solely contaminated with CuSO? more than 80 years ago and from a corresponding control soil. Pollution-induced bacterial community tolerance (PICT) to Cu and a panel of antibiotics was determined by a novel cultivation-independent approach based on [3H]bromodeoxyuridine (BrdU) incorporation into DNA and by resistance profiling of soil bacterial isolates on solid media. High Cu exposure selected for Cu-tolerant bacterial communities but also coselected for increased community-level tolerance to tetracycline and vancomycin. Cu-resistant isolates showed significantly higher incidence of resistance to five out of seven tested antibiotics (tetracycline, olaquindox, nalidixic acid, chloramphenicol, and ampicillin) than Cu-sensitive isolates. Our BrdU-PICT data demonstrate for the first time that soil Cu exposure coselects for resistance to clinically important antibiotics (e.g., vancomycin) at the bacterial community-level. Our study further indicates that Cu exposure provides a strong selection pressure for the expansion of the soil bacterial resistome.     

Xenoendocrine pollutants may reduce size of sexual organs in East Greenland polar bears (Ursus maritimus)

Reproductive organs from 55 male and 44 female East Greenland polar bears were examined to investigate the potential negative impact from organohalogen pollutants (OHCs). Multiple regressions normalizing for age showed a significant inverse relationship between OHCs and testis length and baculum length and weight, respectively, and was found in both subadults (dichlorodiphenyl trichloroethanes, dieldrin, chlordanes, hexacyclohexanes, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs)) and adults (hexachlorobenzene [HCB]) (all p < 0.05). Baculum bone mineral densities decreased with increasing chlordanes, DDTs, and HCB in subadults and adults, respectively (all p < 0.05). In females, a significant inverse relationship was found between ovary length and sigma PCB (p = 0.03) and sigma CHL (p < 0.01), respectively, and between ovary weight and sigma PBDE (p < 0.01) and uterine horn length and HCB (p = 0.02). The study suggests thatthere is an impact from xenoendocrine pollutants on the size of East Greenland polar bear genitalia. This may pose a riskto this polar bear subpopulation in the future because of reduced sperm and egg quality/quantity and uterus and penis size/robustness.     

RNA Dynamics by NMR Spectroscopy

An ever-increasing number of functional RNAs require a mechanistic understanding. RNA function relies on changes in its structure, so-called dynamics. To reveal dynamic processes and higher energy structures, new NMR methods have been developed to elucidate these dynamics in RNA with atomic resolution. In this Review, we provide an introduction to dynamics novices and an overview of methods that access most dynamic timescales, from picoseconds to hours. Examples are provided as well as insight into theory, data acquisition and analysis for these different methods. Using this broad spectrum of methodology, unprecedented detail and invisible structures have been obtained and are reviewed here. RNA, though often more complicated and therefore neglected, also provides a great system to study structural changes, as these RNA structural changes are more easily defined—Lego like—than in proteins, hence the numerous revelations of RNA excited states.     

Antioxidant and antilisterial activity of olive oil,cocoa and rosemary extract polyphenols

Antibacterial and antioxidant activity of polyphenols from olive oil, cocoa, and rosemary extract was tested. Antimicrobial activity against Listeria strains was assessed using broth dilution and time-kill curve methods. The 2,2-diphenyl-2-picrylhydracyl hydrate (DPPH) radical scavenging method, Folin–Ciocalteu method, and high performance liquid chromatography (HPLC) were used for phenolics identification and determination of antioxidants level. Antibacterial and antioxidant activity of main pure phenolic compounds, such as hydroxytyrosol in olive oil, epicatechin in cocoa and carnosic acid in rosemary was each compared with their extracts.     

Metal content determination in four fish species from the Adriatic Sea

Concentrations of As, Cd, Cu, Hg and Pb were measured by atomic absorption spectrometry (AAS) in muscle tissues of four fish species: anchovy (Engraulis encrasicholus), mackerel (Scomber japonicus), red mullet (Mullus surmuletus) and picarel (Spicara smaris) from the Croatian waters of the Adriatic Sea during 2008 and 2009. Metal levels measured in anchovy were in the following ranges (mg kg⁻¹): As 0.01–54.8, Cd 0.001–0.02, Cu 0.001–6.29, Hg 0.001–0.52 and Pb 0.001–0.34 mg kg⁻¹. Metal ranges in red mullet were (mg kg⁻¹): As 0.01–70.9, Cd 0.002–0.85, Cu 0.001–57.3, Hg 0.001–2.07 and Pb 0.001–0.27 mg kg⁻¹. Metal level ranges measured in mackerel were (mg kg⁻¹): As 0.01–36.4, Cd 0.001–0.1, Cu 0.001–15.9, Hg 0.001–0.78 and Pb 0.002–0.24 mg kg⁻¹. In picarel, metal level ranges were (mg kg⁻¹): As 0.01–54.6, Cd 0.001–0.1, Cu 0.08–32.9, Hg 0.001–0.207 and Pb 0.001–0.46 mg kg⁻¹. Significant differences in metal concentrations were found among fish species. The results presented on metal contents in the examined species give an indication of the environmental conditions. Concentrations of Cd, Cu, Hg and Pb obtained were far below the established values by the European Community regulations. However, arsenic levels found in red mullet were higher than the recommended legal limits for human consumption and as such may present a human health issue.     

Evaluation of a Novel Plasmid for Simultaneous Gene Electrotransfer-Mediated Silencing of CD105 and CD146 in Combination with Irradiation

Targeting tumor vasculature through specific endothelial cell markers represents a promising approach for cancer treatment. Here our aim was to construct an antibiotic resistance gene-free plasmid encoding shRNAs to simultaneously target two endothelial cell markers, CD105 and CD146, and to test its functionality and therapeutic potential in vitro when delivered by gene electrotransfer (GET) and combined with irradiation (IR). Functionality of the plasmid was evaluated by determining the silencing of the targeted genes using qRT-PCR. Antiproliferative and antiangiogenic effects were determined by the cytotoxicity assay tube formation assay and wound healing assay in murine endothelial cells 2H-11. The functionality of the plasmid construct was also evaluated in malignant melanoma tumor cell line B16F10. Additionally, potential activation of immune response was measured by induction of DNA sensor STING and proinflammatory cytokines by qRT-PCR in endothelial cells 2H-11. We demonstrated that the plasmid construction was successful and can efficiently silence the expression of the two targeted genes. As a consequence of silencing, reduced migration rate and angiogenic potential was confirmed in 2H-11 endothelial cells. Furthermore, induction of DNA sensor STING and proinflammatory cytokines were determined, which could add to the therapeutic effectiveness when used in vivo. To conclude, we successfully constructed a novel plasmid DNA with two shRNAs, which holds a great promise for further in vivo testing.     

Lipids and Antiplatelet Therapy: Important Considerations and Future Perspectives

Lipids play an essential role in platelet functions. It is known that polyunsaturated fatty acids play a role in increasing platelet reactivity and that the prothrombotic phenotype plays a crucial role in the occurrence of major adverse cardiovascular events. The ongoing increase in cardiovascular diseases’ incidence emphasizes the importance of research linking lipids and platelet function. In particular, the rebound phenomenon that accompanies discontinuation of clopidogrel in patients receiving dual antiplatelet therapy has been associated with changes in the lipid profile. Our many years of research underline the importance of reduced HDL values for the risk of such a rebound effect and the occurrence of thromboembolic events. Lipids are otherwise a heterogeneous group of molecules, and their signaling molecules are not deposited but formed “on-demand” in the cell. On the other hand, exosomes transmit lipid signals between cells, and the profile of such changes can be monitored by lipidomics. Changes in the lipid profile are organ-specific and may indicate new drug action targets.