[The pattern of relationships between nanosciences, health, and biology: a historical survey using Citespace]. / Padrão de relacionamento entre nanociências, saúde e biologia: um levantamento histórico utilizando o programa Citespace.

The article traces a pattern of relationships between nanosciences, health, and biology to provide a historical overview of the nanoscience field. Input data came from the Web of Science databank, through a search first based on the keywords 'nanoscience' and 'nanotechnology' and also the selection of words related to biology and health. Application of the Citespace program made it possible to visualize the pattern of relationships between topics in the research base, allowing identification of burst and centrality points on the subject. Data findings show that the relationship between these areas emerged in 2006, most of them related to nanomedicine. There are also a significant number of works on nanotoxicology, since these two areas necessarily come hand in hand.

Fullerene and omega-3 and omega-6 fatty acids on fish brain antioxidant status.

The carbon nanomaterial fullerene (C(60)) can act as anti or pro-oxidant. The aim of this study was to evaluate, in cell suspensions of carp brains (Cyprinus carpio, Cyprinidae), the effect of C(60) after a pre-treatment with polyunsaturated fatty acid (PUFAs) such as omega-3 (docosahexaenoic acid, DHA) and omega-6 (linoleic acid, LA). Assays consisted of a pre-treatment with PUFA (48 h) and then exposure to C(60) (2 h). Cell viability and total anti-oxidant capacity did not differ (p > 0.05). A reduction (p < 0.05) was observed in reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) concentration in fish brain cells pre-exposed with PUFA groups and then exposed or not with C(60). An antioxidant effect of C(60) was evident since in control group (cells not pre-exposed to PUFA), a significant (p < 0.05) reduction of intracellular ROS concentration was observed, although this reduction was not enough to reduce the TBARS levels. Cysteine levels presented a reduction (p < 0.05) in all groups exposed to C(60). For glutathione (GSH), an increase (p < 0.05) was registered in cells exposed to C(60) without PUFAs pre-treatment and in the C(60) group pre-treated with DHA. Overall C(60) appears to play an antioxidant role that is modulated by PUFA, taking into account its effects on intracellular ROS concentration and MDA levels. Results also suggest that C(60) influences GSH synthesis, as showed for the augmented levels of this antioxidant and also for the lowering of the intracellular cysteine concentration.

Antioxidant responses in different body regions of the polychaeta Laeonereis acuta (Nereididae) exposed to copper.

Antioxidant enzymes, total antioxidant capacity (TOSC) and concentration of reactive oxygen species (ROS) were measured in anterior (A), middle (M) and posterior (P) body regions of Laeonereis acuta after copper (Cu; 62.5 microg/l) exposure. A catalase (CAT) activity gradient observed in control group (lowest in A, highest in P) was not observed in Cu exposed group. Glutathione-S-transferase (GST) activity in A region of Cu group was higher than in A region of the control group. DNA damage (comet assay) was augmented in the A region of Cu group. Since copper accumulation was similar in the different body regions, sensitivity to copper in A regions seems to be related to lowest CAT activity. In sum, copper exposure lowered TOSC, a result that at least in part can be related to lowering of antioxidant enzymes like CAT. DNA damage was induced in the anterior region, where a lower CAT activity was observed.

Photodynamic action of benzo[a]pyrene in K562 cells.

Benzo[a]pyrene (BaP) is ubiquitously distributed in the environment, being considered the most phototoxic element among polycyclic aromatic hydrocarbon (PAHs). In presence of oxygen, PAHs can act as a photosensitizer by means of promoting photo-oxidation of biological molecules (photodynamic action, PDA). Thus, the present study analyzed the photodynamic action of BaP under UVA irradiation (BaP + UVA) and its oxidative effects on K562 cells. The evaluation of BaP kinetics showed that the highest intracellular concentration occurred after 18 h of incubation. Cell viability, reactive oxygen species (ROS) generation, lipid peroxidation, DNA damage (breaks and DNA-protein cross-link [DNAPC]) were assessed after exposure to BaP, UVA and BaP plus UVA irradiation (BaP + UVA). Cell viability was decreased just after exposure to BaP + UVA. Lipid peroxidation and DNA breaks increased after BaP + UVA exposure, while the DNAPC increased after BaP, UVA and BaP + UVA exposure, suggesting that BaP + UVA effects were a consequence of both type II (producing mainly singlet oxygen) and type I (producing others ROS) mechanisms of PDA.

Biomarkers in croakers Micropogonias furnieri (Teleostei: Sciaenidae) from polluted and non-polluted areas from the Patos Lagoon estuary (Southern Brazil): evidences of genotoxic and immunological effects.

Biomarkers of exposure and effect of pollutants were analyzed in croakers Micropogonias furnieri (Teleostei: Sciaenidae) captured in winter and summer in a polluted and in a non-polluted site at the Patos Lagoon estuary (Southern Brazil). Catalase and glutathione S-transferase activities (exposure biomarkers) and lipid peroxidation (effect biomarker) were analyzed in liver samples. Other two effect biomarkers were also studied: blood cells DNA damage (through comet assay and micronucleus test) and respiratory burst measurements. In a broad view, results point to an important seasonal variation of the biochemical biomarkers analyzed. However, data obtained clearly indicate that croakers collected in winter at the polluted site were subjected to a level of clastogenic agents sufficient to generate irreversible genetic damages (mutations) and impair the fish immune system.

Behavioral and neurotoxic effects of arsenic exposure in zebrafish (Danio rerio, Teleostei: Cyprinidae).

This study investigated the passive avoidance conditioning in zebrafish (Danio rerio). An instrument was developed for measuring escape responses triggered by a conditioned stimulus. This system allowed quantification of latency of crossing from a light to a dark zone. Zebrafish were trained to swim from an illuminated to a dark compartment, where they received a body shock (training session). The proposed methodology was efficient for evaluation of working, short, and long-term memory formation of an aquatic animal model. The possibility of employing memory measurements in toxicity tests, in order to obtain an ecologically meaningful biomarker response, was also analyzed. In this experiment, immediately after the training session, fish were exposed to three arsenic (As(V)) concentrations. After the test session, the brain was removed for biochemical analyses. A control group was kept in tap water. After exposure, animals were submitted to a one-trial inhibitory avoidance test for measurement of long-term memory (LTM). Results from behavioral and biochemical analyses showed that the three As(V) concentrations impaired LTM (p<0.05) and increased protein oxidation, which suggests an amnesic and pro-oxidant effect of As(V). Evaluation of behavior parameters in aquatic models is an important complement in studies concerning the environmental impact of chemical substances.

Padrao de relacionamento entre nanociencias, saude e biologia: um levantamento historico utilizando o programa Citespace / The pattern of relationships between nanosciences, health, and biology: a historical survey using Citespace

Traça um padrão de relacionamento entre nanociências, saúde e biologia para estabelecer um panorama histórico no campo das nanociências. Utilizou-se o banco de dados Web of Science, com levantamento inicial pelas palavras-chave nanoscience e nanotechnology e também de palavras relacionadas a biologia e saúde. A aplicação do programa Citespace permitiu visualizar o padrão de relacionamento entre os tópicos lançados na base de pesquisa, proporcionando identificação de momentos de explosão e de ruptura do tema. Os dados obtidos mostram que a relação entre essas áreas emerge a partir de 2006, estando a maioria relacionada a nanomedicina. Trabalhos sobre nanotoxicologia também aparecem de forma significativa, uma vez que essas duas áreas necessitam caminhar juntas.

The article traces a pattern of relationships between nanosciences, health, and biology to provide a historical overview of the nanoscience field. Input data came from the Web of Science databank, through a search first based on the keywords ‘nanoscience' and ‘nanotechnology' and also the selection of words related to biology and health. Application of the Citespace program made it possible to visualize the pattern of relationships between topics in the research base, allowing identification of burst and centrality points on the subject. Data findings show that the relationship between these areas emerged in 2006, most of them related to nanomedicine. There are also a significant number of works on nanotoxicology, since these two areas necessarily come hand in hand.