Coordinate and redox interactions of epinephrine with ferric and ferrous iron at physiological pH

Coordinate and redox interactions of epinephrine (Epi) with iron at physiological pH are essential for understanding two very different phenomena - the detrimental effects of chronic stress on the cardiovascular system and the cross-linking of catecholamine-rich biopolymers and frameworks. Here we show that Epi and Fe3+ form stable high-spin complexes in the 1:1 or 3:1 stoichiometry, depending on the Epi/Fe3+ concentration ratio (low or high). Oxygen atoms on the catechol ring represent the sites of coordinate bond formation within physiologically relevant bidentate 1:1 complex. Redox properties of Epi are slightly impacted by Fe3+. On the other hand, Epi and Fe2+ form a complex that acts as a strong reducing agent, which leads to the production of hydrogen peroxide via O-2 reduction, and to a facilitated formation of the Epi-Fe3+ complexes. Epi is not oxidized in this process, i.e. Fe2+ is not an electron shuttle, but the electron donor. Epi-catalyzed oxidation of Fe2+ represents a plausible chemical basis of stress-related damage to heart cells. In addition, our results support the previous findings on the interactions of catecholamine moieties in polymers with iron and provide a novel strategy for improving the efficiency of cross-linking.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3040

Travel-associated Legionnaires disease in residents from England and Wales travelling to Corfu, Greece, August to October 2011.

Fourteen cases of Legionnaires’ disease were confirmed in residents from England and Wales with history of travel to Corfu, Greece, in the 14 days before symptom onset. These cases were reported to the Health Protection Agency national surveillance scheme for Legionnaires’ disease in residents of England and Wales between August and October 2011. In addition, one case in a Greek national and a case of non-pneumonic legionellosis in a resident from Scotland were also reported. Few cases shared the same accommodation site in Corfu during their incubation period. Epidemiological investigations and microbiological analysis of clinical and environmental samples excluded a single source but rather implicated several accommodation sites as sources of sporadic infection. Control measures have since been implemented at these accommodation sites and no further cases have been reported. This incident highlights the value of epidemiological typing and the importance of effective international response to control and prevent legionella infection

Ion chromatographic separation of alkylsulphonic acids with conductivity detection

An ion chromatographic (IC) method has been developed for the separation of alkylsulphonic acid. Two different stationary phases, silica-based and polymer-based ion-exchange resins, were studied using pure ion exchange and/or hydrophobic interaction mechanisms. Correlations between analyte hydrophobicity and eluent polarity were made in order to investigate the possibility of changing the dominant separation mechanism by varying the eluent composition. The alkyl chain lengths of the sulphonic acids analysed ranged from C-1 to C-9. Detection limits in the submicromolar range were obtained by suppressed conductivity detection

The use of mosses as environmental metal pollution indicators

Naturally growing mosses have been extensively employed for surveying trace metal deposition from the atmosphere. Mosses represent suitable monitors for assessing the long-term accumulation of deposited airborne metals by virtue of their physicochemical properties. Indeed, they occur in almost all terrestrial ecosystems because, for their ability to tolerate long periods of drought, they may even colonize areas with extreme environmental conditions; they obtain most of their elemental supply from the atmosphere and efficiently retain many elements received from precipitation because they have a high surface:volume ratio, a simple anatomy and no cuticle. The monitoring technique using mosses has, therefore, led to reliable estimates of large-scale geographic patterns of trace metal deposition, in spite of possible flaws due to variabilities in local elemental concentrations and interferences with soil dust contamination. While in northern Europe from the late 1960s mosses have been used as passive or active bioindicators, the countries in southern Europe have initiated to participate to the European programme on heavy metal atmospheric deposition in Europe measured from mosses only since 1995. The objectives of the present chapter are therefore: i) to show the last developments of the biomonitoring technique by mosses in Europe; ii) to compare the surveys made in European southern countries, namely France, Spain and Italy; iii) to indicate the changes made to the recommendations of European protocol defined by R\ufchling in 1994 because of different environmental conditions in these geographic areas; iv) to provide information that can be useful for the next large-scale surveys. Finally, as moss biomonitoring example, a more detailed study is reported regarding the use of mosses as environmental bioindicators in order to evaluate the metal atmospheric deposition in different areas in Piedmont (Italy)