Electron paramagnetic resonance of the free radicals in the gas-and particulate phases of cigarette smoke using spin-trapping. ARKIVOC

Abstract Free radicals in cigarette smoke have been studied using spin trapping EPR techniques. 2R4F reference cigarettes were smoked using 35 ml puff volumes of 2 seconds duration, once every 60 seconds. The particulate phase of the smoke was separated from the gas phase by passing the smoke through a Cambridge filter pad. For both phases, free radicals were measured and identified. A range of spin-traps was employed: PBN, DMPO, DEPMPO, and DPPH-PBN. In the gas-phase, short-lived carbon-and oxygen-centered radicals were identified; the ratios between them changed during the smoking runs. For the first puffs, C-centered radicals predominated while for the later puffs, O-centered radicals were mainly observed. The particulate phase and the 'tar' were studied as well

Silver Azide Nanoparticles Embedded into Silica as Energetic Nano-materials

Silver azide is a primary high explosive that can be initiated by different means. In this work, silver azide nanoparticles were obtained, embedded into silica, and further derivatized with biotin. TEM, DLS, and IR measurements were used to characterize the hybrid energetic nanoparticles. The hybrid nanoparticles are made from an explosive core (silver azide) and a shell (silica), to which has been attached through an organic linker a biological target vectot (biotin).These hybrid nanoparticles can be used as models to study smart energetic nano-materials.DOI: http://dx.doi.org/10.5755/j01.ms.21.3.6926</p

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

The Chemistry of DPPH· Free Radical and Congeners

Since the discovery in 1922 of 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl stable free radical (DPPH·), the chemistry of such open-shell compounds has developed continuously, allowing for both theoretical and practical advances in the free radical chemistry area. This review presents the important, general and modern aspects of the chemistry of hydrazyl free radicals and the science behind it

Laccase&ndash;TEMPO as an Efficient System for Doxorubicin Removal from Wastewaters

A large number of drugs are used to treat different diseases, and thus to improve the quality of life for humans. These represent a real ecological threat, as they end up in soil or ground waters in amounts that can affect the environment. Among these drugs, doxorubicin is a highly cytotoxic compound used as anticancer medicine. Doxorubicin can be efficiently removed from wastewater or polluted water using a simple enzymatic (biocatalytic) system, employing the oxidoreductase enzyme laccase and a stable organic nitroxide-free radical, TEMPO. Results presented in this work (as percentage of removal) were obtained at pH 5 and 7, after 2, 4, 6, and 24 h, using different ratios between doxorubicin, laccase, and TEMPO. It was shown that longer time, as well as an increased amount of catalyst, led to a higher percentage of removal, up to 100%. The influence of all these parameters is also discussed. In this way it was shown that the laccase&ndash;TEMPO biocatalytic system is highly efficient in the removal of the anticancer drug doxorubicin from wastewaters

Synthesis and Structural Analysis of a Nitrobenzofurazan Derivative of Dibenzo-18-Crown-6 Ether

Nitrobenzofurazan derivatives are well known for their fluorescence, whilst crown ethers are known for their complexing capacity toward cationic species. In this study, we present the synthesis and structural characterization of a new derivative containing both nitrobenzofurazan moieties and a crown ether core. The new compound was obtained from dibenzo-18-crown-6 ether, which was first nitrated, reduced to the corresponding amine, and subsequently derivatized with NBD. Structural analyses performed by IR, NMR, UV–Vis, and MS confirmed its structure and physico-chemical behavior toward the complexation of alkaline cations

Synthesis and Structural Analysis of a Nitrobenzofurazan Derivative of Dibenzo-18-Crown-6 Ether

Nitrobenzofurazan derivatives are well known for their fluorescence, whilst crown ethers are known for their complexing capacity toward cationic species. In this study, we present the synthesis and structural characterization of a new derivative containing both nitrobenzofurazan moieties and a crown ether core. The new compound was obtained from dibenzo-18-crown-6 ether, which was first nitrated, reduced to the corresponding amine, and subsequently derivatized with NBD. Structural analyses performed by IR, NMR, UV&ndash;Vis, and MS confirmed its structure and physico-chemical behavior toward the complexation of alkaline cations