Detection of Human Bocavirus mRNA in Respiratory Secretions Correlates with High Viral Load and Concurrent Diarrhea

Human bocavirus (HBoV) is a parvovirus recently identified in association with acute respiratory infections (ARI). Despite its worldwide occurrence, little is known on the pathogenesis of HBoV infections. In addition, few systematic studies of HBoV in ARI have been conducted in Latin America. Therefore, in order to test whether active viral replication of human bocavirus is associated with respiratory diseases and to understand the clinical impact of this virus in patients with these diseases, we performed a 3-year retrospective hospital-based study of HBoV in outpatients and inpatients with symptoms of Acute Respiratory Infections (ARI) in Brazil. Nasopharyngeal aspirates (NPAs) from 1015 patients with respiratory symptoms were tested for HBoV DNA by PCR. All samples positive for HBoV were tested by PCR for all other respiratory viruses, had HBoV viral loads determined by quantitative real time PCR and, when possible, were tested by RT-PCR for HBoV VP1 mRNA, as evidence of active viral replication. HBoV was detected in 4.8% of patients, with annual rates of 10.0%, 3.0% and 3.0% in 2005, 2006 and 2007, respectively. The range of respiratory symptoms was similar between HBoV-positive and HBoV-negative ARI patients. However, a higher rate of diarrhea was observed in HBoV-positive patients. High HBoV viral loads (>108 copies/mL) and diarrhea were significantly more frequent in patients with exclusive infection by HBoV and in patients with detection of HBoV VP1 mRNA than in patients with viral co-infection, detected in 72.9% of patients with HBoV. In summary, our data demonstrated that active HBoV replication was detected in a small percentage of patients with ARI and was correlated with concurrent diarrhea and lack of other viral co-infections

Antioxidant/pro-oxidant properties of phenolic imidazole derivatives

Fundação para a Ciência e a Tecnologia (FCT) - nºF-COMP-01-0124-FEDER-022716 (ref. FCT PEst-/QUI/UI0686/2011) FEDER-COMPETE and National NMR Network (Bruker 400 Avance III).Thanks are due to the University of Minho, FCT: project nºF-COMP-01-0124-FEDER-022716 (ref. FCT PEst-/QUI/UI0686/2011) FEDER-COMPETE and National NMR Network (Bruker 400 Avance III)

Synthesis and radical scavenging activity of phenol–imidazole conjugates

Novel hydroxylated benzylideneamino imidazole derivatives were synthesized and their radical scavenging activity was assessed against DPPH and hydroxyl radicals. In the DPPH assay, most of the synthesized compounds showed an IC50 in the range 3.2 mu M <= IC50 <= 8.4 mu M, lower than the reference compound trolox (IC50 = 9.5 mu M) or the parent aldehydes (5.4 mu M <= IC50 <= 11.6 mu M). The activity depends mainly on the phenolic subunit (number and position of the hydroxyl groups) and the extent of conjugation with the imidazole ring. In the deoxyribose assay, all the compounds, including parent imidazoles and aldehydes, showed high activity against the hydroxyl radical and the ability to chelate iron ions. At 5 mu M concentration, the compounds protected the deoxyribose from degradation by hydroxyl radical between 62% and 38%. (C) 2014 Elsevier Ltd. All rights reserved.The authors gratefully acknowledge the financial support to Universidade do Minho, Centro de Quimica and Fundacao para a Ciencia e Tecnologia (project nF-COMP-01-0124-FEDER-022716 (Ref. FCT PEst-/QUI/UI0686/2011) FEDER-COMPETE, FCT-Portugal, a PhD Grant awarded to C. Correia (SFRH/BD/22270/2005) and support to the NMR spectrometer (Bruker 400 Avance III) that is part of the National NMR Network

Electrochemical evaluation of the antioxidant capacity of hydroxylated benzylideneamino imidazole derivatives

Oxidative stress (OS) has been associated with a wide range of diseases such as atherosclerosis, cancer, and neurodegenerative disorders [1-3]. Oxidative stress occurs when intracellular oxidizing species, such as reactive oxygen species (ROS), increase abnormally and is often accompanied by a simultaneous loss of antioxidant capacity [4]. Therefore, the development and synthesis of new compounds (drugs) that are able to scavenge ROS or prevent their formation are important for the prevention and therapy of these diseases. Numerous methods can then be applied to evaluate the compounds antioxidant capacity and, both chemical and electrochemical methods have been used with this purpose [5,6]. A few studies demonstrated that imidazole-containing compounds are active as antioxidant agents [7]. On the other hand the antioxidant activity of several phenolic compounds is known for a long time. As part of a research program aiming to obtain new antioxidants we synthesized new compounds combining an imidazole ring with phenolic units. The novel hydroxylated benzylideneamino imidazole derivatives combined an imidazole ring with electron withdrawing or electron donating substituents in N1, and phenolic subunits having one, two or three hydroxyl groups in different positions of the ring. In this work, the antioxidant capacity of the new phenol-imidazole conjugates and of the starting imidazoles and aldehydes, was assessed by voltammetric methods. Antioxidant capacity data obtained from cyclic voltammetry measurements were correlated with DPPH radical assay data. It was found that the antioxidant capacity of hydroxylated benzylideneamino imidazole derivatives depends mainly on the phenolic subunit (number and position of the hydroxyl groups) and the extent of conjugation with the imidazole ring