Silver nanoparticle stabilized by hydrolyzed collagen and natural polymers: Synthesis, characterization and antibacterial-antifungal evaluation.

In synthesis of silver nanoparticles (AgNPs), the composition of the stabilizer used can be closely related to the effectiveness of the synthesis and to the shape of the final nanoparticles. Recently, the use of collagen as an effective nanoparticle stabilization agent was reported. In this work, synthesis of silver nanoparticles using mixed capping agents is reported. The capping agents used were cashew gum-hydrolyzed collagen; kappa carrageenan-hydrolyzed collagen, and agar-hydrolyzed collagen. We evaluated antibacterial action against Gram-positive and Gram-negative bacteria, as well as antifungal activity and cytotoxicity. Homogenized mixtures of collagen and aqueous cashew gum, carrageenan or agar respectively were used to produce the nanoparticles AgNPcolCashew, AgNPcolCarr and AgNPcolAgar. AgNP characterization was performed using Uv-vis, XRD, TEM and DLS and the biological activities were assayed using MIC and MBC analyses for both antibacterial and antifungal application. Results showed that the AgNPcollcar sample showed the strongest bacterial inhibition with MIC values of 62.5 and 31.25 µM/mL Ag against E. coli and P. aeruginosa respectively. Interestingly, AgNPcollAgar also presented the lowest cytotoxicity when compared with other AgNPs and AgNO3.

Imidazole alkaloids inhibit the pro-inflammatory mechanisms of human neutrophil and exhibit anti-inflammatory properties in vivo.

OBJECTIVES: Epiisopiloturine (EPI) and epiisopilosine (EPIIS) are side products in the pharmaceutical industry. The present study aimed to investigate the anti-inflammatory potential of the alkaloids EPI and EPIIS in human neutrophils and mechanical hyperalgesia in mice. METHODS: Neutrophils (5 × 106  cells/ml) incubated with EPI and EPIIS and stimulated by the addition of N-formyl-methionyl-leucyl-phenylalanine or phorbol 12-myristate-13-acetate. The release of myeloperoxidase (MPO), reactive oxygen species (ROS) production, calcium influx, gene expression of NF-κB and pro-inflammatory cytokines production were evaluated. It was also investigated the effect these alkaloids on carrageenan-induced mechanical hyperalgesia model in mice. KEY FINDINGS: We demonstrated that both EPI and EPIIS inhibited the degranulation of activated neutrophils. This effect was accompanied by the reduction in ROS, the prevention of the increase in intracellular Ca2+ and decrease in the density of cytosolic NF-κB, and inhibition of TNF-α and IL-6 production. Evaluating hypernociception in mice, EPI and EPIIS inhibited carrageenan-induced inflammatory hypernociception and reduced MPO levels. CONCLUSIONS: The results obtained suggest EPI and EPIIS not only inhibit neutrophils functions in vitro, but also exhibits anti-inflammatory properties in vivo, acting through the modulation of the activation and/or accumulation of neutrophils in the inflammatory focus. Thus, EPI and EPIIS possess promising anti-inflammatory therapeutic potential.

Self-nanoemulsifying drug-delivery systems improve oral absorption and antischistosomal activity of epiisopiloturine.

AIM: To develop a self-nanoemulsifying drug-delivery system (SNEDDS) able to improve oral absorption of epiisopiloturine (EPI), and test the antischistosomal activity in a mice model. RESULTS: SNEDDS had a nanoscopic size and was able to enhance EPI bioavailability after oral administration, and SNEDDS-EPI (40 mg.kg-1) improved the in vivo antischistosomal activity of EPI, demonstrating that SNEDDS was able to improve the pharmacokinetics of EPI, and to maintain the pharmacodynamic activity against Schistosoma mansoni in vivo. CONCLUSION: Taken together, these results indicate that SNEDDS-EPI is efficient in reducing worm burden in comparison to treatment with the free version of EPI. [Formula: see text].

Synergistic effects of in vitro combinations of piplartine, epiisopiloturine and praziquantel against Schistosoma mansoni.

Schistosomiasis is a world health problem, and praziquantel is the only drug currently used for the treatment. There is some evidence that extensive monotherapy of praziquantel may be leading to drug resistance in the parasite. In order to find alternative treatments, the effects of the combination of epiisopiloturine (EPI), piplartine (PPT) and praziquantel (PZQ) were evaluated. Similarity analysis of these compounds was performed using optimized molecular structures to compare the shape and the charge modeling of combinations between PZQ and EPI or PPT. Supported by this data, in vitro association of PZQ-PPT, PZQ-EPI, and EPI-PPT was carried out, and the activity of these combinations against Schistosoma mansoni was assessed. The results showed synergistic activity with a combination index (CI) of 0.42 for the treatment with PZQ-PPT. Both PZQ-EPI and EPI-PPT combinations also showed synergistic effects, with CI values of 0.86 and 0.61, respectively. Surface alterations in the tegument of adult schistosomes after the treatments were observed using laser confocal microscopy and scanning electron microscopy. Additionally, the association of EPI-PPT decreased the cytotoxicity when compared with both isolated compounds in three different lines of mammalian cells. Thus, synergistic combinations of PZQ-PPT, PZQ-EPI, and EPI-PPT create the possibility of reduced doses to be used against Schistosoma mansoni.

Acetylated cashew gum-based nanoparticles for transdermal delivery of diclofenac diethyl amine.

Nanoprecipitation and dialysis methods were employed to obtain nanoparticles (NPs) of acetylated cashew gum (ACG). NPs synthesized by dialysis showed greater average size compared to those synthesized by nanoprecipitation, but they presented improved stability and yield. NPs were loaded with diclofenac diethylamine and the efficiency of the drug incorporation was over 60% for both methods, for an ACG:NP a weight ratio of 10:1. The cytotoxicity assay demonstrated that the NPs had no significant effect on the cell viability, verifying their biocompatibility. The release profile for the diclofenac diethylamine associated with the ACG-NPs showed a more controlled release compared to the free drug and a Fickian diffusion mechanism was observed. Transdermal permeation reached 90% penetration of the drug.

Imaging aspects of dentigerous cyst through magnetic resonance imaging and ultrasound / Aspectos imaginológicos do cisto dentígero por meio de ressonância magnética e ultrassonografia

Magnetic resonance imaging (MRI) is a type of imaging examination considered as gold standard in the analysis of the internal structure and content of intra-osseous lesions. Because of the inherent characteristics of acquisition, MRI allows determining the nature and differential diagnosis among alterations that have aspects similar to those of other imaging modalities, such as radiographs and computed tomography (CT). Moreover, MRI main advantage is to be a non-invasive method, because it does not use ionizing radiation. Both ultrasound (US) and MRI provides images without showing deleterious effects to living organisms, enabling the differentiation between solid and cystic lesions, but US lacks to provide comprehensive anatomical detail and information about the chemical composition of the lesions as MRI, which would be crucial in determining the lesion diagnosis. This paper reports the clinical case of a child exhibiting dentigerous cyst along the whole extension of the right maxillary sinus with extensive tooth displacement, aiming to emphasize the use of both MRI and US in the diagnosis of dentomaxillofacial lesions.

A Ressonância Magnética (RM) é uma modalidade de exame por imagem considerada padrão ouro na análise da estrutura e do conteúdo interno das lesões intraósseas, possibilitando, por suas características inerentes de aquisição, determinar a natureza e o diagnóstico diferencial entre alterações que possuam aspectos similares em outras modalidades de imagem, como por exemplo em radiografias e tomografia computadorizada (TC), além de possuir a grande vantagem de não ser um método invasivo, uma vez que não utiliza radiações ionizantes. A Ultrassonografia (US), assim como a RM, fornece imagens sem apresentar efeitos deletérios aos organismos vivos, possibilitando a diferenciação entre lesões sólidas e císticas, porém, não possui a capacidade da RM em fornecer um detalhamento anatômico apurado, e nem informações sobre a composição química das lesões, o que seria fundamental na determinação do diagnóstico das mesmas. O presente trabalho expõe o caso clínico de uma criança, que apresentou um cisto dentígero em toda extensão do seio maxilar direito com amplo deslocamento dentário, em que se objetivou enfatizar o uso da RM e US no diagnóstico de lesões dentomaxilofaciais.