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Herein is delineated a first systematic framework for the definition of structure‐antioxidant property relationships in the dihydroxynaphthalene (DHN) series. The results obtained by a combined experimental and theoretical approach revealed that 1,8‐DHN is the best performing antioxidant platform, with its unique hydrogen‐bonded peri‐hydroxylation pattern contributing to a fast H atom transfer process. Moreover, the comparative analysis of the antioxidant properties of DHNs carried out by performing DPPH and FRAP assays and laser flash photolysis experiments, revealed the higher antioxidant power associated with an α‐substitution pattern (i. e. in 1,8‐ and 1,6‐DHN) with respect to DHNs exhibiting a β‐substitution pattern (i. e. in 2,6‐ and 2,7‐DHN). DFT calculations and isolation and characterization of the main oligomer intermediates formed during the oxidative polymerization of DHNs supported this evidence by providing unprecedented insight into the generation and fate of the intermediate naphthoxyl radicals, which emerged as the main factor governing the antioxidant activity of DHNs. [ABSTRACT FROM AUTHOR]

Developing effective strategies to increase the chemical stability and to fine‐tune the physico‐chemical properties of melanin biopolymers by rational control of π‐electron conjugation is an important goal in materials science for biomedical and technological applications. Herein we report that poly‐1,8‐dihydroxynaphthalene (pDHN), a non‐nitrogenous, catechol‐free fungal melanin mimic, displays a high degree of structural integrity (from MALDI‐MS and CP/MAS 13C NMR analysis), a strong radical scavenging capacity (DPPH and FRAP assays), and an unusually intense EPR signal (g=2.0030). Morphological and spectral characterization of pDHN, along with deassembly experiments in ionic liquids, indicated amorphous aggregates of small globular structures with an estimated stacking distance of 3.9 Å and broadband absorption throughout the visible range. These results indicate that DHN‐based melanins exhibit a high structural integrity and enhanced antioxidant and free‐radical properties of potentially greater biomedical and technological relevance than for typical indole‐based eumelanins. [ABSTRACT FROM AUTHOR]

Objectives: Social support (SS) influences the elderly ability to cope with the losses of ageing process. This study was aimed at assessing SS among elderly users of a primary healthcare unit in a poor and violent area of Rio de Janeiro City, and at verifying its association with depression, self-perceived health (SPH), marital status and chronic illnesses. Methods: A cross-sectional study was performed based on a convenience sample of 180 individuals aged 60 years or older. SS was measured with part of the Brazilian version of Medical Outcomes Study's SS scale, and SPH and depression were assessed, respectively, through one question and the Brazilian version of the Structured Clinical Interview for DSM-IV Axis I Disorders. SS medians were calculated for the categories of SPH, depression, marital status and chronic illnesses variables, and differences were evaluated with the Kruskal-Wallis and Mann-Whitney tests. Additionally, Pearson's chi-square test and logistic regression were employed to identify unadjusted and adjusted associations between SS and those variables. Results: The participant’s mean age was 73 years old, and level of education was 3 years of school education on average. They were predominantly females (73.3%), and non-married (55.0%). Among them, 74.4% perceived their SS as satisfactory, 55.0% perceived their health as good, 27.8% were diagnosed with major depression and 83.3% had hypertension. Especially for those depressed and with bad SPH, the medians of SS measure were much lower than for others, reaching an unsatisfactory level. Moreover, controlling for other factors, non-depressed individuals were more likely (OR = 2.32) to have satisfactory SS. Conclusion: in the violent and poor area explored in this research low SS is highly prevalent in the elderly. Depressed individuals are more likely to have low SS and this condition should be investigated in depressed elderly. The reduced scale is useful for low education individuals. [ABSTRACT FROM AUTHOR]

Formation and structural modification of oxygenated polycyclic aromatic hydrocarbons (oxyPAHs) by UV irradiation on minerals have recently been proposed as a possible channel of PAH transformation in astrochemical and prebiotic scenarios of possible relevance for the origin of life. Herein, it is demonstrated that high‐energy proton‐beam irradiation in the presence of various meteorites, including stony iron, achondrite, and chondrite types, promotes the conversion of two representative oxyPAH compounds, 1‐naphthol and 1,8‐dihydroxynaphthalene, to complex mixtures of oxygenated and oligomeric derivatives. The main identified products include polyhydroxy derivatives, isomeric dimers encompassing benzofuran and benzopyran scaffolds, and, notably, a range of quinones and perylene derivatives. Addition of urea, a prebiotically relevant chemical precursor, expanded the range of identified species to include, among others, quinone diimines. Proton‐beam irradiation of oxyPAH modulated by nitrogen‐containing compounds such as urea is proposed as a possible contributory mechanism for the formation and processing of insoluble organic matter in meteorites and in prebiotic processes. [ABSTRACT FROM AUTHOR]

Objective: The treatment of tobacco addiction in Brazil has expanded in recent years; however, we must increase knowledge about the characteristics of individuals who adhere to cessation programs in order to adjust treatments to specific characteristics of the target population that favor success. The aim of this study was to describe the characteristics of smokers who present to Brazilian public health units seeking help to quit smoking based on the experience of a primary health care unit that covers a poor community in the city of Rio de Janeiro. Methods: Data were collected at a Teaching Health Center from January 03 2012 to January 03 2014. Results: Mean patient age was 49.32±11.82 years, and 71% were women. About half of the participants successfully quit smoking (n=125, 51%). Higher levels of nicotine dependence were associated with lower levels of smoking cessation. There was a notable decrease in the probability of remaining smoking throughout the first month of treatment. After 3 weeks of treatment, only 19% had not quit smoking. The probability of quitting smoking decreases by 2% for every additional year of age. Conclusion: There is a need to revise and expand current strategies to make them more effective in preventing smoking since childhood. [ABSTRACT FROM AUTHOR]