Universidade Estadual de Londrina

About: Universidade Estadual de Londrina is a education organization based out in Londrina, Brazil. It is known for research contribution in the topics: Population & Toxoplasma gondii. The organization has 13052 authors who have published 19291 publications receiving 212123 citations.

The citrus flavonoid naringenin impairs the in vitro infection of human cells by Zika virus.

Abstract: The Zika virus (ZIKV) is an arthropod-borne virus that belongs to the Flaviviridae family. The ZIKV infection is usually asymptomatic or is associated with mild clinical manifestations; however, increased numbers of cases of microcephaly and birth defects have been recently reported. To date, neither a vaccine nor an antiviral treatment has become available to control ZIKV replication. Among the natural compounds recognized for their medical properties, flavonoids, which can be found in fruits and vegetables, have been found to possess biological activity against a variety of viruses. Here, we demonstrate that the citrus flavanone naringenin (NAR) prevented ZIKV infection in human A549 cells in a concentration-dependent and ZIKV-lineage independent manner. NAR antiviral activity was also observed when primary human monocyte-derived dendritic cells were infected by ZIKV. NAR displayed its antiviral activity when the cells were treated after infection, suggesting that NAR acts on the viral replication or assembly of viral particles. Moreover, a molecular docking analysis suggests a potential interaction between NAR and the protease domain of the NS2B-NS3 protein of ZIKV which could explain the anti-ZIKV activity of NAR. Finally, the results support the potential of NAR as a suitable candidate molecule for developing anti-ZIKV treatments.

Determination of the Kinetics and Thermodynamics Parameters of Biodiesel Oxidation Reaction Obtained from an Optimized Mixture of Vegetable Oil and Animal Fat

Abstract: The temperature influence on the oxidation stability of biodiesel from ternary mixture of vegetable oil and animal fat (50% of soybean oil, 20% of beef tallow, and 30% of poultry fat) was evaluated at temperatures ranging from 110 to 130 °C applying the Arrhenius and Eyring equations. The kinetics and thermodynamics parameters determined, considering first-order reaction rate kinetics, were rate constant (k), varying from 0.5479 to 1.7110 h–1, activation energy (Ea) of 72.01 kJ mol–1, pre-exponential factor (A) of 3.84 × 109 h–1, enthalpy of activation (ΔH‡) of 68.75 kJ mol–1, entropy of activation (ΔS‡) of −72.05 J K–1 mol–1, and Gibb’s free energy of activation (ΔG‡) average of 97.08 kJ mol–1. Based on the activation complex theory (ACT), the thermodynamic activation parameters indicated a nonspontaneous, endergonic, and endothermic process: ΔG‡ > 0, ΔH‡ > 0, and ΔS‡ < 0, with estimated storage time of 149.82 d at 25 °C.

Herpesvirus: an underestimated virus.

Abstract: Herpes simplex virus (HSV) infections are common and widespread; nevertheless, their outcome can be of unpredictable prognosis in neonates and in immunosuppressed patients. Anti-HSV therapy is effective, but the emergence of drug-resistant strains or the drug toxicity that hamper the treatment is of great concern. Vaccine has not yet shown relevant benefit; therefore, palliative prophylactic measures have been adopted to prevent diseases. This short review proposes to present concisely the history of HSV, its taxonomy, physical structure, and replication and to explore the pathogenesis of the infection, clinical manifestations, laboratory diagnosis, treatment, prophylaxis and epidemiology of the diseases.