Seroprevalence of SARS-CoV-2 antibodies in the poorest region of Brazil: results from a population-based study.

Population-based seroprevalence studies on coronavirus disease 2019 (COVID-19) in low- and middle-income countries are lacking. We investigated the seroprevalence of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) antibodies in Sergipe state, Northeast Brazil, using rapid IgM-IgG antibody test and fluorescence immunoassay. The seroprevalence was 9.3% (95% CI 8.5-10.1), 10.2% (95% CI 9.2-11.3) for women and 7.9% (IC 95% 6.8-9.1) for men (P = 0.004). We found a decline in the prevalence of SARS-CoV-2 antibodies according to age, but the differences were not statistically significant: 0-19 years (9.9%; 95% CI 7.8-12.5), 20-59 years (9.3%; 95% CI 8.4-10.3) and ≥60 years (9.0%; 95% CI 7.5-10.8) (P = 0.517). The metropolitan area had a higher seroprevalence (11.7%, 95% CI 10.3-13.2) than outside municipalities (8.0%, 95% CI 7.2-8.9) (P < 0.001). These findings highlight the importance of serosurveillance to estimate the real impact of the COVID-19 outbreak and thereby provide data to better understand the spread of the virus, as well as providing information to guide stay-at-home measures and other policies. In addition, these results may be useful as basic data to follow the progress of COVID-19 outbreak as social restriction initiatives start to be relaxed in Brazil.

Development of morin/hydroxypropyl-ß-cyclodextrin inclusion complex: Enhancement of bioavailability, antihyperalgesic and anti-inflammatory effects.

Morin is a flavonoid has been reported with several pharmacological effects such as, antioxidant, anti-inflammatory, anticancer, antidiabetic, etc. However, morin has low solubility in water, which decreases the bioavailability and limits its clinical application. In this way, to improve the pharmaceutical properties, morin was complexed in hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and its oral bioavailability and anti-inflammatory effects were evaluated. Initially, a phase solubility study was performed, which showed that HP-ß-CD would be the better cyclodextrin for the formation of complexes with morin. The morin/HP-ß-CD inclusion complex (1:1) was prepared by freeze-drying method. The sample obtained was characterized by DSC, FTIR, PXRD, SEM and 1H NMR techniques, evidencing the formation of morin/HP-ß-CD inclusion complex. In addition, complexation efficiency (98.3%) and loading content (17.63%), determined by HPLC demonstrated that morin was efficiently complexed in HP-ß-CD. In vitro dissolution study confirmed that morin/HP-ß-CD inclusion complex increased the solubility and dissolution rate of morin. The oral bioavailability of the morin/HP-ß-CD complex and free morin were evaluated through a pharmacokinetic study in rat plasma. The oral bioavailability of morin complexed with HP-ß-CD was increased by 4.20 times compared with the free morin. Hyperalgesia induced by carrageenan and carrageenan-induced pleurisy were carried out in mice to evaluate the antihyperalgesic and anti-inflammatory activities of free morin and inclusion complex. Morin/HP-ß-CD inclusion complex showed antihyperalgesic effect in inflammatory pain model and anti-inflammatory effect decreasing leukocyte migration and TNF-α levels at a lower dose than free morin. Therefore, the morin/HP-ß-CD inclusion complex improved the solubility, dissolution rate, oral bioavailability, antihyperalgesic and anti-inflammatory effects of morin. In this way, the morin/HP-ß-CD inclusion complex exhibits potential for development of new pharmaceutical product for future clinical applications.