Antibody-coated nanoparticles have recently attracted considerable attention, with the focus falling on diagnostics. Nevertheless, controlled antibody bioconjugation remains a challenge. Here, we present two strategies of bioconjugation with the aim of evaluating the best approach for the coupling of antibodies on the surface of nanomaterials in an oriented way. We employed electrostatic interaction (physical adsorption) and covalent conjugation in the orientation of antibodies on the metallic surface as coupling methods, and their influence on the detection of 17β-estradiol was addressed with localized surface plasmon resonance. The understanding of these mechanisms is fundamental for the development of reproducible inorganic bioconjugates with oriented surface as well sensibility of immunoassays.

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The biosynthesis of metallic nanoparticles (NPs) using biological systems such as fungi has evolved to become an important area of nanobiotechnology. Herein, we report for the first time the extracellular synthesis of highly stable silver NPs (AgNPs) using the nematophagous fungus Duddingtonia flagrans (AC001). The fungal cell-free filtrate was analyzed by the Bradford method and 3,5-dinitrosalicylic acid assay and used to synthesize the AgNPs in the presence of a 1 mM AgNO 3 solution. They have been characterized by UV–Vis spectroscopy, X-ray diffraction, transmission electron microscopy, dynamic light scattering, Zeta potential measurements, Fourier-transform infrared, and Raman spectroscopes. UV–Vis spectroscopy confirmed bioreduction, while X-ray diffractometry established the crystalline nature of the AgNPs. Dynamic light scattering and transmission electron microscopy images showed approximately 11, 38 nm monodisperse and quasispherical AgNPs. Zeta potential analysis was able to show a considerable stability of AgNPs. The N–H stretches in Fourier-transform infrared spectroscopy indicate the presence of protein molecules. The Raman bands suggest that chitinase was involved in the growth and stabilization of AgNPs, through the coating of the particles. Our results show that the NPs we synthesized have good stability, high yield, and monodispersion.

Contrast-induced nephropathy (CIN) is an iatrogenic medical event for which there is not yet a successful therapy. Increasing evidence in rodents has suggested that this disease is associated with renal tubular and vascular injury that is triggered directly by oxidative stress. In the present study, we evaluated whether the antioxidant resin from Virola oleifera (RV) could attenuate renal damage in an experimental mouse model of CIN. Adult male Swiss mice were divided into six groups and pre-treated orally with RV (10, 100 and 300 mg/kg), N-acetylcysteine (200 mg/kg) or vehicle for 5 days before the induction of CIN and Control group. Renal function was assessed by measuring plasma creatinine and urea levels. Additionally, renal oxidative stress and apoptosis/cell viability were determined with flow cytometry. Finally, kidney tissues were sectioned for histopathological examination. In this CIN model, pre-treatment with RV improved renal function, lowered the mortality rate, and reduced oxidative stress and apoptosis in both the medulla and cortex renal cells in a dose-dependent manner. Moreover, the RV treatment had beneficial effects on kidney histopathology that were superior to the standard treatment with N-acetylcysteine. These data suggest that because of its antioxidative and antiapoptotic effects and its ability to preserve renal function, resin from Virola oleifera may have potential as a new therapeutic approach for preventing CIN.

In translational medicine, the discovery of new drugs or new potential uses for currently available drugs is crucial for treating the resistant hypertension associated with renal artery stenosis. The phosphodiesterase 5 inhibitor sildenafil has been shown to reduce blood pressure and to improve the endothelium-dependent relaxation in the two kidney, one clip (2K1C) mouse model of renovascular hypertension. In the present study, we evaluated the effects of sildenafil (40 mg/kg/day for two weeks) on the endothelial structure and contractile function in mesenteric resistance arteries 28 days after clipping the renal artery. The data showed an enhanced vascular contractile response to norepinephrine in 2K1C hypertensive mice (56%) when compared with Sham mice, which was associated with increased oxidative stress and with a thinning of endothelial cells. Sildenafil treatment caused a significant amelioration in the enhanced contractile responsiveness (18%), which was associated to the recovery of the endothelial surface and abolishment of the oxidative stress. These data suggest that sildenafil could be considered a promising therapeutic option to manage endothelial dysfunction and hypertension in resistant patients.

Achyrocline satureioides or Macela, has been largely used in traditional folk medicine in Brazil as an anti-inflammatory agent and to treat various digestive disorders. The aim of the present study was to evaluate the preventive action of the extracts of A. satureioides obtained by maceration and ultrasound-assisted extraction, quercetin and N-acetylcysteine against contrast-induced nephropathy in mice. The antioxidant activity, cytotoxicity and inhibition of nitric oxide (NO) production in macrophages were evaluated. Also, chemical analyses of phenolic compounds, total flavonoids, and quercetin by LC-MS/MS present in various extracts of A. satureioides were performed. Thirty six mice were divided into six groups: control group (C), Contrast-Induced Nephropathy group (CIN), Group N-acetylcysteine 200mg/kg (NAC); Group quercetin 10mg/kg (Q), Group Macela 10mg/kg (M10), and Group Macela 50mg/kg (M50). The serum levels of urea and creatinine, advanced oxidation protein products (AOPP) and renal ultrastructure were evaluated by electron microscopy scanning. Ultrasound-assisted extraction improved the quality of extract (with 100% ethanol), since did not show toxicity to fibroblasts, and showed potent antioxidant activity and a high content of phenolic compounds, flavonoids, and quercetin, in addition to being able to reduce the production of NO in dose-dependent effect in macrophages. Results showed that animals treated with Macela extracts maintained normal levels of urea, creatinine, and AOPP, while preserving ultrastructure of the renal cells. The obtained results were more promising than NAC and Q groups in protecting against renal failure caused by CIN, showing that the plant can be a promising drug for preventing this disease.

INTO BIOFUELS. Oily waste from sanitation processes was characterized for its potential use in the generation of biofuels. The waste residues studied showed high levels of oil and grease, reaching up to 87% (m/m) in a grease trap of a food company, showing that these residues can be utilized for the production of biofuels. The results revealed high levels of moisture and saponification as well as high levels of free fatty acids (FFA). Analysis of chromatographic profiles (HPLC) showed great heterogeneity of the fatty acids contained in the sample, and a predominance of palmitic, oleic, linoleic and linolenic acids.Keywords: oily sanitary waste; biofuels; chromatographic profile. INTRODUÇÃOEstabelecimentos alimentares, domésticos e comerciais geram grandes volumes de efluentes que contém quantidades significativas de óleos e graxas residuais (OGRs). Antes de entrar nos sistemas de coleta e tratamento, os OGRs presentes nos efluentes devem ser removidos, principalmente devido à sua propensão para bloquear as linhas de esgoto municipais e reduzir a eficiência do processo a jusante do seu tratamento. 1 O tratamento de águas residuárias domésticas é dificultado pela grande quantidade de OGRs nelas despejados. A água usada na cozinha, por exemplo, traz grande quantidade destes produtos, provenientes principalmente da limpeza dos utensílios, que podem representar até 50% dos compostos orgânicos em suspensão presente nas águas residuárias domésticas.2 As gorduras presentes nesta suspensão são ésteres de alto peso molecular, formados a partir de ácidos graxos superiores (C12 a C22) e glicerol. A baixa solubilidade em água das longas cadeias carbônicas, além de provocar entupimentos nas tubulações por incrustações e prejudicar o tratamento biológico (aeróbio/anaeróbio) nas ETE's (Estações de Tratamento de Efluentes), caracteriza os OGRs como grandes fontes de contaminação do solo e dos recursos hídricos, quando dispostos diretamente.Uma alternativa para minimizar o acúmulo do material lipídico no efluente é o uso de caixas de gordura. Tais dispositivos são utilizados como tratamento preliminar na remoção de OGRs de efluentes. O material que se acumula ao longo do tempo nas caixas de gordura é denominado escuma.3 A escuma gerada no tratamento de esgoto consiste em materiais flutuantes compostos por graxa, óleos, gorduras, sabões, resíduos alimentares, cascas de vegetais e frutas, cabelo, papel, algodão, pontas de cigarros e materiais similares. Devido aos elevados teores de OGRs, a escuma apresenta alto potencial a ser utilizada como matéria-prima na produção de biodiesel.Além da escuma, pesquisas recentes têm indicado que os lipídeos contidos no lodo de esgoto constituem matéria prima potencial para a produção de biodiesel. Dados da literatura indicam que aproximadamente 20% do conteúdo do lodo são OGRs solúveis em éter, os quais podem ser convertidos em ésteres metílicos ou etílicos de ácidos graxos. 4 Os autores concluíram que a integração de processos de extração de lipídeos em 50% das estações de tratamento de esgoto ...