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.

Noninvasive method to estimate anaerobic threshold in individuals with type 2 diabetes

Abstract: While several studies have identified the anaerobic threshold (AT) through the responses of blood lactate, ventilation and blood glucose others have suggested the response of the heart rate variability (HRV) as a method to identify the AT in young healthy individuals. However, the validity of HRV in estimating the lactate threshold (LT) and ventilatory threshold (VT) for individuals with type 2 diabetes (T2D) has not been investigated yet. To analyze the possibility of identifying the heart rate variability threshold (HRVT) by considering the responses of parasympathetic indicators during incremental exercise test in type 2 diabetics subjects (T2D) and non diabetics individuals (ND). Nine T2D (55.6 ± 5.7 years, 83.4 ± 26.6 kg, 30.9 ± 5.2 kg.m2(-1)) and ten ND (50.8 ± 5.1 years, 76.2 ± 14.3 kg, 26.5 ± 3.8 kg.m2(-1)) underwent to an incremental exercise test (IT) on a cycle ergometer. Heart rate (HR), rate of perceived exertion (RPE), blood lactate and expired gas concentrations were measured at the end of each stage. HRVT was identified through the responses of root mean square successive difference between adjacent R-R intervals (RMSSD) and standard deviation of instantaneous beat-to-beat R-R interval variability (SD1) by considering the last 60 s of each incremental stage, and were known as HRVT by RMSSD and SD1 (HRVT-RMSSD and HRVT-SD1), respectively. No differences were observed within groups for the exercise intensities corresponding to LT, VT, HRVT-RMSSD and HHVT-SD1. Furthermore, a strong relationship were verified among the studied parameters both for T2D (r = 0.68 to 0.87) and ND (r = 0.91 to 0.98) and the Bland & Altman technique confirmed the agreement among them. The HRVT identification by the proposed autonomic indicators (SD1 and RMSSD) were demonstrated to be valid to estimate the LT and VT for both T2D and ND.

The azo dyes Disperse Red 1 and Disperse Orange 1 increase the micronuclei frequencies in human lymphocytes and in HepG2 cells

Abstract: The use of azo dyes by different industries can cause direct and/or indirect effects on human and environmental health due to the discharge of industrial effluents that contain these toxic compounds. Several studies have demonstrated the genotoxic effects of various azo dyes, but information on the DNA damage caused by Disperse Red 1 and Disperse Orange 1 is unavailable, although these dyes are used in dyeing processes in many countries. The aim of the present study was to evaluate the mutagenic activity of Disperse Red 1 and Disperse Orange 1 using the micronucleus (MN) assay in human lymphocytes and in HepG2 cells. In the lymphocyte assay, it was found that the number of MN induced by the lowest concentration of each dye (0.2 microg/mL) was similar to that of the negative control. At the other concentrations, a dose response MN formation was observed up to 1.0 microg/mL. At higher dose levels, the number of MN decreased. For the HepG2 cells the results were similar. With both dyes a dose dependent increase in the frequency of MN was detected. However for the HepG2, the threshold for this increase was 2.0 microg/mL, while at higher doses a reduction in the MN number was observed. The proliferation index was also calculated in order to evaluate acute toxicity during the test. No differences were detected between the different concentrations tested and the negative control.

Influência do processo de familiarização para avaliação da força muscular em testes de 1-RM

Abstract: RESUMENInfluencia del proceso de familiarizacion para evaluacion de lafuerza muscular en tests de 1-RM Embora la utilizacion de tests de una repeticion maxima (1-RM)es frecuente para la evaluacion de la fuerza muscular, se acreditaque los resultados obtenidos puedan ser afectados por la falta defamiliarizacion previa, hasta mismo en sujetos con experiencia enejercicios con pesos. Asi, el objetivo de este estudio fue investigarel impacto del proceso de familiarizacion para evaluacion de la fuerzamuscular en tests de 1-RM. Por lo tanto, 21 hombres (24,5 ± 3,8anos), aparentemente saludables con experiencia previa de por lomenos seis meses de entrenamiento con pesos, fueron someti-dos a tests reptitivos de 1-RM en los ejercicios supino en bancohorizontal, agachamiento y rosca directa de biceps. Los tests fue-ran ejecutados en cuatro sesiones, intervaladas en cada 48-72 ho-ras. Un numero maximo de tres tentativas, con intervalo de tres acinco minutos para recuperacion, fue utilizado en cada ejercicio,en las cuatro sessiones de testeo. ANOVA se utilizo para medidasrepetidas, seguida por el test post hoc de Tukey, cuando p ≤ 0,05,fue utilizada para el tratamiento de los datos. Aumentos significan-tes en la fuerza muscular (p ≤ 0,01) fueron encontrados los tresejercicios analizados entre la primera y la cuarta sesion de familia-rizacion (2,4% en supino en banco horizontal, 3,4% en agacha-miento y 5,4% en la rosca directa del biceps). Todavia, ningunadiferencia estadisticamente significativamente fuera encontradaentre la segunda y la cuarta sesion de familiarizacion en la roscadirecta de biceps (p > 0,05), bien con entre la tercera y la cuartasesion en el supino en el banco horizontal y en el agachamiento ( p> 0,05). Los resultados indican que la falta de familiarizacion previacon tests de 1-RM puede comprometer la evaluacion de la fuerzamuscular. Por lo tanto, se sugiere para la evaluacion mas acuradade la fuerza muscular mediante tests de 1-RM la ejecucion de dosa tres sesiones de familiarizacion en los hombres adultos con ex-periencia en ejercicios con pesos.

Regulatory T cells and breast cancer: implications for immunopathogenesis.

Abstract: Current understanding of the role of several cancer risk factors is more comprehensive, as reported for a number of sites, including the brain, colon, breasts, and ovaries. Despite such advances, the incidence of breast cancer continues to increase worldwide. Signals from the microenviroment have a profound influence on the maintenance or progression cancers. Although T cells present the most important immunological response in tumor growth in the early stages of cancer, they become suppressive CD4(+) and CD8(+) regulatory T cells (Tregs) after chronic stimulation and interactions with tumor cells, thus promoting rather than inhibiting cancer development and progression. Tregs have an important marker protein which is FoxP3, though it does not necessarily confer a Treg phenotype when expressed in CD4(+) T lymphocytes. High Treg levels have been reported in peripheral blood, lymph nodes, and tumor specimens from patients with different types of cancer. The precise mechanisms by which Tregs suppress immune cell functions remain unclear, and there are reports of both direct inhibition through cell-cell contact and indirect inhibition through the secretion of anti-inflammatory mediators such as interleukin. In this review, we present the molecular and immunological aspects of Treg cells in the metastasis of breast cancer.