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BACKGROUND AND PURPOSE Acute lung injury (ALI) is a critical disorder that has high mortality rates, and pharmacological therapies are so far ineffective. The pathophysiology of ALI involves pulmonary oxidative stress and inflammatory response. Fullerol is a carbon nanocomposite that possesses antioxidant and anti-inflammatory properties. Here, we evaluated the therapeutic potential of fullerol and its mechanisms in a model of paraquat-induced ALI. EXPERIMENTAL APPROACH Rats were divided into ALI (paraquat alone), fullerol (paraquat plus fullerol), and control groups. Survival curves were estimated using the Kaplan-Meier method. The myeloperoxidase assay, ELISA, and hematoxylin and eosin staining were used to determine neutrophils infiltration, cytokines production, and histopathological parameters in lung samples, respectively. The antioxidant effect of fullerol was evaluated in vitro and ex vivo. KEY RESULTS Fullerol (0.01 to 0.3 mg/kg) markedly reduced the severe lung injury and high mortality rates observed in ALI rats. Moreover, fullerol (0.03 mg/kg) inhibited the reactive oxygen species formation and lipid peroxidation seen in lungs from ALI rats, and exhibited a potent concentration-dependent (10 to 10 mg/ml) in vitro antioxidant activity. Importantly, fullerol (0.03 mg/kg) inhibited neutrophils accumulation in bronchoalveolar lavage and lungs, and the increase in pulmonary levels of TNF-α, IL-1β, IL-6, and CINC-1 in ALI rats. CONCLUSIONS AND IMPLICATIONS Fullerol treatment was effective in reducing pulmonary damage and ALI-induced mortality, highlighting its therapeutic potential in an ALI condition. Searching for new pharmacological therapies to treat ALI may be desirable especially in view of the new coronavirus disease 2019 that currently plagues the world.

As questoes eticas e legais na atualidade tem sido amplamente debatidas devido a deficiencia ou a incompreensao de regulamentacao. O Consolidated Standards of Reporting Trials 2010 foi utilizado como base, porque e uma ferramenta que colabora para a padronizacao das pesquisas clinicas tornando um objeto mais claro para o leitor e para o pesquisador. METODO: Foi feita uma analise critica de 24 artigos oriundos das bases de dados do Literatura Latino-Americana e do Caribe em Ciencias da Saude, Medical Literature Analisys and Retrieval System on Line e Scientific Eletronic Library onLine, da Agencia Nacional de Vigilância Sanitaria e da Comissao Nacional de Etica em Pesquisa entre os de 1996 e 2017, durante 6 meses. OBJETIVO: O presente trabalho visa direcionar individuos que desejam fazer o delineamento de uma pesquisa clinica. CONCLUSAO: As questoes eticas devem permanecer regulamentando as pesquisas clinicas em todos os aspectos. A observância as recomendacoes internacionais e nacionais tornam a pesquisa clinica etica e legalmente ideal, assegurando a protecao dos sujeitos da pesquisa e do pesquisador, evitando pesquisas motivadas por interesses capitalistas.

Visceral leishmaniasis (VL) is a systemic parasitic disease that leads to high rates of morbidity and mortality in humans worldwide. There is a great need to develop new drugs and novel strategies to make chemotherapy for this disease more efficacious and well tolerated. Recent reports on the immunomodulatory effects and the low toxicity of the spherical carbon nanostructure fullerol led us to investigate in vitro and in vivo antileishmanial activity in free and encapsulated forms in liposomes. When assayed against intramacrophagic Leishmania amastigotes, fullerol showed a dose-dependent reduction of the infection index with IC50 of 0.042 mg/mL. When given daily by i.p. route for 20 days (0.05 mg/kg/d) in a murine model of acute VL, fullerol promoted significant reduction in the liver parasite load. To improve the delivery of fullerol to the infection sites, liposomal formulations were prepared by the dehydration-rehydration method. When evaluated in the acute VL model, liposomal fullerol (Lip-Ful) formulations given i.p. at 0.05 and 0.2 mg/kg with 4-days intervals were more effective than the free form, with significant parasite reductions in both liver and spleen. Lip-Ful at 0.2 mg/kg promoted complete parasite elimination in the liver. The antileishmanial activity of Lip-Ful was further confirmed in a chronic model of VL. Lip-Ful was also found to induce secretion of pro-inflammatory TNF-α, IFN-γ and IL-1β cytokines. In conclusion, this work reports for the first time the antileishmanial activity of fullerol and introduces an innovative approach for treatment of VL based on the association of this nanostructure with liposomes.

As questões éticas e legais na atualidade têm sido amplamente debatidas devido à deficiência ou à incompreensão de regulamentação. O Consolidated Standards of Reporting Trials 2010 foi utilizado como base, porque é uma ferramenta que colabora para a padronização das pesquisas clínicas tornando um objeto mais claro para o leitor e para o pesquisador. MÉTODO: Foi feita uma análise crítica de 24 artigos oriundos das bases de dados do Literatura Latino-Americana e do Caribe em Ciências da Saúde, Medical Literature Analisys and Retrieval System on Line e Scientific Eletronic Library onLine, da Agência Nacional de Vigilância Sanitária e da Comissão Nacional de Ética em Pesquisa entre os de 1996 e 2017, durante 6 meses. OBJETIVO: O presente trabalho visa direcionar indivíduos que desejam fazer o delineamento de uma pesquisa clínica. CONCLUSÃO: As questões éticas devem permanecer regulamentando as pesquisas clínicas em todos os aspectos. A observância às recomendações internacionais e nacionais tornam a pesquisa clínica ética e legalmente ideal, assegurando a proteção dos sujeitos da pesquisa e do pesquisador, evitando pesquisas motivadas por interesses capitalistas.

Graphene and its derivatives, due to a wide range of unique properties that they possess, can be used as starting material for the synthesis of useful nanocomplexes for innovative therapeutic strategies and biodiagnostics. Here, we summarize the latest progress in graphene and its derivatives and their potential applications for drug delivery, gene delivery, biosensor and tissue engineering. A simple comparison with carbon nanotubes uses in biomedicine is also presented. We also discuss their in vitro and in vivo toxicity and biocompatibility in three different life kingdoms (bacterial, mammalian and plant cells). All aspects of how graphene is internalized after in vivo administration or in vitro cell exposure were brought about, and explain how blood–brain barrier can be overlapped by graphene nanomaterials.

Background Succinate is an intermediate of the citric acid cycle as well as an extracellular circulating molecule, whose receptor, G protein-coupled receptor-91 (GPR91), was recently identified and characterized in several tissues, including heart. Because some pathological conditions such as ischemia increase succinate blood levels, we investigated the role of this metabolite during a heart ischemic event, using human and rodent models. Results We found that succinate causes cardiac hypertrophy in a GPR91 dependent manner. GPR91 activation triggers the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), the expression of calcium/calmodulin dependent protein kinase IIδ (CaMKIIδ) and the translocation of histone deacetylase 5 (HDAC5) into the cytoplasm, which are hypertrophic-signaling events. Furthermore, we found that serum levels of succinate are increased in patients with cardiac hypertrophy associated with acute and chronic ischemic diseases. Conclusions These results show for the first time that succinate plays an important role in cardiomyocyte hypertrophy through GPR91 activation, and extend our understanding of how ischemia can induce hypertrophic cardiomyopathy. Electronic supplementary material The online version of this article (doi:10.1186/s12964-014-0078-2) contains supplementary material, which is available to authorized users.

Cholinergic control of the heart is exerted by two distinct branches; the autonomic component represented by the parasympathetic nervous system, and the recently described non-neuronal cardiomyocyte cholinergic machinery. Previous evidence has shown that reduced cholinergic function leads to deleterious effects on the myocardium. Yet, whether conditions of increased cholinergic signaling can offset the pathological remodeling induced by sympathetic hyperactivity, and its consequences for these two cholinergic axes are unknown. Here, we investigated two models of sympathetic hyperactivity: i) the chronic beta-adrenergic receptor stimulation evoked by isoproterenol (ISO), and ii) the alpha(2A)/alpha(2C)-drenergic receptor knockout (KO) mice that lack pre-synaptic adrenergic receptors. In both models, cholinergic signaling was increased by administration of the cholinesterase inhibitor, pyridostigmine. First, we observed that isoproterenol produces an autonomic imbalance characterized by increased sympathetic and reduced parasympathetic tone. Under this condition transcripts for cholinergic proteins were upregulated in ventricular myocytes, indicating that non-neuronal cholinergic machinery is activated during adrenergic overdrive. Pyridostigmine treatment prevented the effects of ISO on autonomic function and on the ventricular cholinergic machinery, and inhibited cardiac remodeling. alpha(2A)/alpha(2C)-KO mice presented reduced ventricular contraction when compared to wild-type mice, and this dysfunction was also reversed by cholinesterase inhibition. Thus, the cardiac parasympathetic system and non-neuronal cardiomyocyte cholinergic machinery are modulated in opposite directions under conditions of increased sympathetic drive or ACh availability. Moreover, our data support the idea that pyridostigmine by restoring ACh availability is beneficial in heart disease.

Recent work has provided compelling evidence that increased levels of acetylcholine (ACh) can be protective in heart failure, whereas reduced levels of ACh secretion can cause heart malfunction. Previous data show that cardiomyocytes themselves can actively secrete ACh, raising the question of whether this cardiomyocyte derived ACh may contribute to the protective effects of ACh in the heart. To address the functionality of this non-neuronal ACh machinery, we used cholinesterase inhibitors and a siRNA targeted to AChE (acetylcholinesterase) as a way to increase the availability of ACh secreted by cardiac cells. By using nitric oxide (NO) formation as a biological sensor for released ACh, we showed that cholinesterase inhibition increased NO levels in freshly isolated ventricular myocytes and that this effect was prevented by atropine, a muscarinic receptor antagonist, and by inhibition of ACh synthesis or vesicular storage. Functionally, cholinesterase inhibition prevented the hypertrophic effect as well as molecular changes and calcium transient alterations induced by adrenergic overstimulation in cardiomyocytes. Moreover, inhibition of ACh storage or atropine blunted the anti-hypertrophic action of cholinesterase inhibition. Altogether, our results show that cardiomyocytes possess functional cholinergic machinery that offsets deleterious effects of hyperadrenergic stimulation. In addition, we show that adrenergic stimulation upregulates expression levels of cholinergic components. We propose that this cardiomyocyte cholinergic signaling could amplify the protective effects of the parasympathetic nervous system in the heart and may counter-act or partially neutralize hypertrophic adrenergic effects.

Spontaneous Ca(2+) events have been observed in diverse stem cell lines, including carcinoma and mesenchymal stem cells. Interestingly, during cell cycle progression, cells exhibit Ca(2+) transients during the G(1) to S transition, suggesting that these oscillations may play a role in cell cycle progression. We aimed to study the influence of promoting and blocking calcium oscillations in cell proliferation and cell cycle progression, both in neural progenitor and undifferentiated cells. We also identified which calcium stores are required for maintaining these oscillations. Both in neural progenitor and undifferentiated cells calcium oscillations were restricted to the G1/S transition, suggesting a role for these events in progression of the cell cycle. Maintenance of the oscillations required calcium influx only through inositol 1,4,5-triphosphate receptors (IP(3)Rs) and L-type channels in undifferentiated cells, while neural progenitor cells also utilized ryanodine-sensitive stores. Interestingly, promoting calcium oscillations through IP(3)R agonists increased both proliferation and levels of cell cycle regulators such as cyclins A and E. Conversely, blocking calcium events with IP(3)R antagonists had the opposite effect in both undifferentiated and neural progenitor cells. This suggests that calcium events created by IP(3)Rs may be involved in cell cycle progression and proliferation, possibly due to regulation of cyclin levels, both in undifferentiated cells and in neural progenitor cells.