Anaerobic Contributions Are Influenced by Active Muscle Mass and The Applied Methodology in Well-Controlled Muscle Group

International Journal of Exercise Science 15(7): 599-615, 2022. The anaerobic metabolism determination is complex and the applied methodologies present limitations. Thus, the purpose of this study was to investigate the effects of different calculations (MAOD vs. AOD) on the anaerobic contribution using the dynamic knee extension. Twenty-four male were recruited [Mean (SD); age 27 (1) years, body mass 90 (3) kg, height 181 (2) cm]. This study was divided into two independent experiments (EXP1: ­one-legged; EXP2: two-legged). In both experiments, it was performed a graded exercise test to determine maximal power (MP-GXT); 2-4 submaximal efforts (VO2-intensity relationship); and an exhaustive effort. The theoretical energy demand for the exhaustive effort (TEDex) was constructed from the submaximal efforts. Therefore, MAOD was assumed as the difference between the TEDex and the accumulated VO2 (AVO2). In contrast, the energy demand for AOD was calculated as the product between VO2 at the end of exercise and time to exhaustion (TEDaod). Thus, AOD was assumed as the difference between TEDaod and AVO2. Bayesian paired t-test was used to compare the differences between the applied methods. Also, correlations between the anaerobic indices and performance were verified. In EXP1, AOD was higher than MAOD [1855 (741) vs. 434 (245); BF10 = 2925; ES = 2.5]. In contrast, in EXP2, MAOD was higher than AOD [2832 (959) vs. 1636 (549); BF10 = 3.33; ES = 1.4]. Also, AOD was correlated to performance (r = .59; BF10 = 4.38). We concluded that MAOD and AOD are a distinct phenomenon and must be utilized according to the exercise model

Blood Group Antigen Studies Using Cdte Quantum Dots And Flow Cytometry.

New methods of analysis involving semiconductor nanocrystals (quantum dots [QDs]) as fluorescent probes have been highlighted in life science. QDs present some advantages when compared to organic dyes, such as size-tunable emission spectra, broad absorption bands, and principally exceptional resistance to photobleaching. Methods applying QDs can be simple, not laborious, and can present high sensibility, allowing biomolecule identification and quantification with high specificity. In this context, the aim of this work was to apply dual-color CdTe QDs to quantify red blood cell (RBC) antigen expression on cell surface by flow cytometric analysis. QDs were conjugated to anti-A or anti-B monoclonal antibodies, as well as to the anti-H (Ulex europaeus I) lectin, to investigate RBCs of A1, B, A1B, O, A2, and Aweak donors. Bioconjugates were capable of distinguishing the different expressions of RBC antigens, both by labeling efficiency and by flow cytometry histogram profile. Furthermore, results showed that RBCs from Aweak donors present fewer amounts of A antigens and higher amounts of H, when compared to A1 RBCs. In the A group, the amount of A antigens decreased as A1 > A3 > AX = Ael, while H antigens were AX = Ael > A1. Bioconjugates presented stability and remained active for at least 6 months. In conclusion, this methodology with high sensibility and specificity can be applied to study a variety of RBC antigens, and, as a quantitative tool, can help in achieving a better comprehension of the antigen expression patterns on RBC membranes.104393-440

Effects of cardiopulmonary bypass on propofol pharmacokinetics and bispectral index during coronary surgery

PURPOSE: Cardiopulmonary bypass is known to alter propofol pharmacokinetics in patients undergoing cardiac surgery. However, few studies have evaluated the impact of these alterations on postoperative pharmacodynamics. This study was designed to test the hypothesis that changes in propofol pharmacokinetics increase hypnotic effects after cardiopulmonary bypass. METHODS: Twenty patients scheduled for on-pump coronary artery bypass graft (group, n=10) or off-pump coronary artery bypass graft (group, n=10) coronary artery bypass grafts were anesthetized with sufentanil and a propofol target controlled infusion (2.0 µg/mL). Depth of hypnosis was monitored using the bispectral index. Blood samples were collected from the induction of anesthesia up to 12 hours after the end of propofol infusion, at predetermined intervals. Plasma propofol concentrations were measured using high-performance liquid chromatography, followed by a non-compartmental propofol pharmacokinetic analysis. Data were analyzed using ANOVA, considering p<0.05 as significant. RESULTS: After cardiopulmonary bypass, despite similar plasma propofol concentrations in both groups, bispectral index values were lower in the on-pump coronary artery bypass graft group. Time to extubation after the end of propofol infusion was greater in the on-pump coronary artery bypass graft group (334 ± 117 vs. 216 ± 85 min, p = 0.04). Patients undergoing cardiopulmonary bypass had shorter biological (1.82 ± 0.5 vs. 3.67 ± 1.15h, p < 0.01) and terminal elimination (6.27 ± 1.29 vs. 10.5h ± 2.18, p < 0.01) half-life values, as well as higher total plasma clearance (28.36 ± 11.40 vs.18.29 ± 7.67 mL/kg/min, p = 0.03), compared to patients in the off-pump coronary artery bypass graft group. CONCLUSION: Aside from the increased sensitivity of the brain to anesthetics after cardiopulmonary bypass, changes in propofol pharmacokinetics may contribute to its central nervous system effects

Manometria esofágica e estudo vetorcardiográfico em pacientes assintomáticos portadores de Doença de Chagas

The indeterminate form of Chagas' disease is characterized by positive serology for the disease in the absence of clinical findings and in the presence of both normal esophagogram and electrocardiogram. When more sensitive methods were used, abnormalities have been described either in the esophagus or in the heart. The authors have studied simultaneously the esophagus and the heart in the same subjects. In thirteen adults with diagnosis of indeterminate form and nine adult controls, the esophageal manometry both in basal conditions and after stimulus (bethanecol) and vectorcardiogram were performed. In the control group none of the subjects presented concomitant esophageal and cardiac alterations while in the chagasic group 92,3% of the patients presented results simultaneously altered. It is concluded that the studied patients showed indications of parasympathetic denervation manifested by simultaneously esophageal and heart alterations.A forma indeterminada da Doença de Chagas é caracterizada por sorologia positiva com ausência de manifestações clínicas, na presença de resultados normais aos exames radiológico do tubo digestivo e eletrocardiográfico. No presente trabalho, os autores estudam simultaneamente o esôfago e o coração, nos mesmos indivíduos. Treze adultos com diagnóstico de forma indeterminada da Doença de Chagas e nove adultos controles foram submetidos ao exame vetorcardiográfico e à manometria esofágica em condições basais e sob estímulo com cloridrato de betanecol (0,08 mg/kg p.c). No grupo controle nenhum dos indivíduos apresentou concomitância de alterações esofágicas e cardíacas, enquanto no grupo chagásico 92,3% dos pacientes apresentaram exames concomitantemente alterados. Concluem que os pacientes estudados apresentam evidências de desnervação parassimpática manifestada por alterações simultâneas esofágicas e cardíacas

Push-out bond strength of fiber posts to root dentin using glass ionomer and resin modified glass ionomer cements

OBJECTIVE: The purpose of this study was to assess the push-out bond strength of glass fiber posts to root dentin after cementation with glass ionomer (GICs) and resinmodified glass ionomer cements (RMGICs). MATERIAL AND METHODS: Fifty human maxillary canines were transversally sectioned at 15 mm from the apex. Canals were prepared with a step back technique until the application of a #55 K-file and filled. Post spaces were prepared and specimens were divided into five groups according to the cement used for post cementation: Luting & Lining Cement; Fuji II LC Improved; RelyX Luting; Ketac Cem; and Ionoseal. After cementation of the glass fiber posts, all roots were stored at 100% humidity until testing. For push-out test, 1-mm thick slices were produced. The push-out test was performed in a universal testing machine at a crosshead speed of 0.5 mm/minute and the values (MPa) were analyzed by Kolmogorov-Smirnov and Levene's tests and by two-way ANOVA and Tukey's post hoc test at a significance level of 5%. RESULTS: Fiber posts cemented using Luting & Lining Cement, Fuji II LC Improved, and Ketac Cem presented the highest bond strength to root dentin, followed by RelyX Luting. Ionoseal presented the lowest bond strength values (P>0.05). The post level did not influence the bond strength of fiber posts to root dentin (P=0.148). The major cause of failure was cohesive at the cement for all GICs and RMGICs. CONCLUSIONS: Except for Ionoseal, all cements provided satisfactory bond strength values