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 & Context (language use). The organization has 13052 authors who have published 19291 publications receiving 212123 citations.

Calibration of ActiGraph GT3X, Actical and RT3 accelerometers in adolescents.

Abstract: The objective of this study was to develop count cut-points for three different accelerometer models: ActiGraph GT3X, RT3 and Actical to accurately classify physical activity intensity levels in adolescents. Seventy-nine adolescents (10-15 years) participated in this study. Accelerometers and oxygen consumption ([Formula: see text]) data were collected at rest and during 11 physical activities of different intensities. Accelerometers were worn on the waist and [Formula: see text] was measured by a portable metabolic system: Cosmed K4b2. Receiver operating characteristic (ROC) curves were used to determine cut-points. Cut-points for sedentary (SED), moderate-to-vigorous (MVPA) and vigorous-intensity physical activity (VPA) were 46, 607 and 818 counts·15s(-1) to the vertical axis of ActiGraph; 180, 757 and 1112 counts·15s(-1) to the vector magnitude of ActiGraph; 17, 441 and 873 counts·15s(-1) for Actical; and 5.6, 20.4 and 32.2 counts·s(-1) for RT3, respectively. For all three accelerometer models, there was an almost perfect discrimination of SED and MVPA (ROC >0.97) and an excellent discrimination of VPA (ROC>0.90) observed. Areas under the ROC curves indicated better discrimination of MVPA by ActiGraph (AUC=0.994) and Actical (AUC=0.993) when compared to RT3 (AUC=0.983). The cut-points developed in this study for the ActiGraph (vector magnitude), RT3 and Actical accelerometer models can be used to monitor physical activity level of adolescents.

Gas-phase Nucleophilic Displacement Reactions

Abstract: Publisher Summary This chapter reviews that gas-phase nucleophilic displacement reactions constitute a mature field of physical organic chemistry. It is a field that provides some unusual insights into the world of solvent-free chemistry, although many experiments remain to be rationalized on a more quantitative basis. The extent to which the understanding of gas-phase reactivity provides an insight into solution behavior by appropriate extrapolation of salvation effects has been under attack recently, and it is a subject of lively discussion. The chapter discusses that the most important lesson that can be derived from these examples is that significantly different chemistry can be generated in ionic reactions in the gas phase. This aspect is one which most theoretical and experimental chemists find intellectually stimulating and a challenge to be pursued.

Quercetin-Loaded Microcapsules Ameliorate Experimental Colitis in Mice by Anti-inflammatory and Antioxidant Mechanisms

Abstract: Quercetin (1) is an anti-inflammatory and antioxidant flavonoid. However, the oral administration of 1 did not lead to beneficial effects in experimental animal colitis models, which involve cytokines and oxidative stress. A possible explanation is that the absorption profile of 1 prevents its activity. Therefore, it was reasoned that the controlled release of 1 would improve its therapeutic effect. Thus, the therapeutic effect and mechanisms of 1-loaded microcapsules in acetic acid-induced colitis in mice were evaluated. Microcapsules were prepared using pectin/casein polymer and 1. The oral administration of 1-loaded microcapsules decreased neutrophil recruitment, attenuated histological alterations, and reduced macroscopical damage, edema, and IL-1β and IL-33 production in the colon samples. Microcapsules loaded with 1 also prevented the reduction of anti-inflammatory cytokine IL-10 and the antioxidant capacity of the colon. These preclinical data indicate that pectin/casein polymer microcapsules loaded with 1 improved the anti-inflammatory and antioxidant effects of 1 compared to the nonencapsulated drug. Therefore, quercetin seems to be a promising active molecule in inflammatory bowel disease if provided with adequate controlled release.