To define training zones, ventilatory thresholds (VTs) are commonly established by cardiopulmonary gas-exchange analysis during incremental exercise tests. Portable near-infrared spectroscopy (NIRS) devices have emerged as a potential tool for detecting these thresholds by monitoring muscle oxygenation. This study evaluated the accuracy of NIRS measurements to determine VTs or critical power (CP) based on muscle oxygen saturation and assesses the device's consistency across 2 constant-load tests.
View Article and Find Full Text PDFFlecainide acetate is a Class 1c anti-arrhythmic with a potent sodium voltage gated channel blockade which is utilized for the second-line treatment of tachyarrhythmias in children and adults. Given its narrow therapeutic index, the individualization of drug therapy is of utmost importance for clinicians. Despite efforts to improve anti-arrhythmic drug therapy, there remain knowledge gaps regarding the impact of variation in the genes relevant to flecainide's disposition and response.
View Article and Find Full Text PDFCoronary artery disease (CAD) remains a leading cause of death worldwide and imposes a substantial socioeconomic burden on healthcare. Improving risk stratification in clinical practice could help to combat this burden. As amino acids are biologically active metabolites whose involvement in CAD remains largely unknown, this study investigated associations between circulating amino acid levels and CAD phenotypes.
View Article and Find Full Text PDFChaperonins are large barrel-shaped complexes that mediate ATP-dependent protein folding. The bacterial chaperonin GroEL forms juxtaposed rings that bind unfolded protein and the lid-shaped cofactor GroES at their apertures. In vitro analyses of the chaperonin reaction have shown that substrate protein folds, unimpaired by aggregation, while transiently encapsulated in the GroEL central cavity by GroES.
View Article and Find Full Text PDFInt J Sports Physiol Perform
August 2024
Objective: To (1) establish extensive physiological profiles of highly trained CrossFit® athletes using gold-standard tests and (2) investigate which physiological markers best correlate with CrossFit Open performance.
Methods: This study encompassed 60 participants (30 men and 30 women), all within the top 5% of the CrossFit Open, including 7 CrossFit semifinalists and 3 CrossFit Games finalists. Isokinetic dynamometers were employed to measure maximum isometric and isokinetic leg and trunk strength.
Acta Crystallogr D Struct Biol
May 2024
Cryo-electron tomography (cryo-ET) enables molecular-resolution 3D imaging of complex biological specimens such as viral particles, cellular sections and, in some cases, whole cells. This enables the structural characterization of molecules in their near-native environments, without the need for purification or separation, thereby preserving biological information such as conformational states and spatial relationships between different molecular species. Subtomogram averaging is an image-processing workflow that allows users to leverage cryo-ET data to identify and localize target molecules, determine high-resolution structures of repeating molecular species and classify different conformational states.
View Article and Find Full Text PDFBeta adrenergic receptor antagonists, known as beta blockers, are one of the most prescribed medications in both pediatric and adult cardiology. Unfortunately, most of these agents utilized in the pediatric clinical setting are prescribed off-label. Despite regulatory efforts aimed at increasing pediatric drug labeling, a majority of pediatric cardiovascular drug agents continue to lack pediatric-specific data to inform precision dosing for children, adolescents, and young adults.
View Article and Find Full Text PDFBackground: Gait changes with aging have been investigated, but few studies have examined a wide range of gait parameters across the adult lifespan. This study aimed to investigate gait differences across age groups stratified by sex.
Methods: This cross-sectional study included 629 healthy, normal-weight (i.
Purpose: The objective was to investigate if performing a sub-peak or supra-peak verification phase following a ramp test provides additional value for determining 'true' maximum oxygen uptake ( O).
Methods: 17 and 14 well-trained males and females, respectively, performed two ramp tests each followed by a verification phase. While the ramp tests were identical, the verification phase differed in power output, wherein the power output was either 95% or 105% of the peak power output from the ramp test.
Cryo-electron tomography (cryo-ET) enables molecular-resolution 3D imaging of complex biological specimens such as viral particles, cellular sections, and in some cases, whole cells. This enables the structural characterization of molecules in their near-native environments, without the need for purification or separation, thereby preserving biological information such as conformational states and spatial relationships between different molecular species. Subtomogram averaging is an image processing workflow that allows users to leverage cryo-ET data to identify and localize target molecules, determine high-resolution structures of repeating molecular species, and classifying different conformational states.
View Article and Find Full Text PDFThe Fontan Udenafil Exercise Longitudinal (FUEL) trial showed that treatment with udenafil was associated with improved exercise performance at the ventilatory anaerobic threshold in children with Fontan physiology. However, it is not known how the initiation of phosphodiesterase 5 inhibitor therapy affects heart rate and blood pressure in this population. These data may help inform patient selection and monitoring after the initiation of udenafil therapy.
View Article and Find Full Text PDFPurpose: Accelerometer-assessed physical activity (PA) can be summarized using cut-point-free or population-specific cut-point-based outcomes. We aimed to 1) examine the interrelationship between cut-point-free (intensity gradient (IG) and average acceleration (AvAcc)) and cut-point-based accelerometer metrics, 2) compare the association between cardiorespiratory fitness (CRF) and cut-point-free metrics to that with cut-point-based metrics in healthy adults aged 20 to 89 yr and patients with heart failure, and 3) provide age-, sex-, and CRF-related reference values for healthy adults.
Methods: In the COmPLETE study, 463 healthy adults and 67 patients with heart failure wore GENEActiv accelerometers on their nondominant wrist and underwent cardiopulmonary exercise testing.
Background And Aim: Heart failure is considered as a systemic disease as beside the heart, skeletal muscle is affected.
Methods And Results: In this retrospective case-control study 64 men and 15 women with heart failure as well as an individually pairwise matched sample by sex, age and body mass index of healthy individuals from the COmPLETE cohort study performed an exhaustive cardiopulmonary exercise test, strength tests and anthropometric measurements. V̇Opeak was 28.
The zeolitic imidazolate framework, ZIF-8, has been shown by experimental methods to have a maximum saturation adsorption capacity of 0.36 g g for -butanol from aqueous solution, equivalent to a loading of 14 butanol molecules per unit cell or 7 molecules per sodalite β-cage. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) shows the presence of hydrogen bonding between adsorbed butanol molecules within the cage; the presence of three different O-H stretching modes indicates the formation of butanol clusters of varying size.
View Article and Find Full Text PDFFlecainide is a class IC antiarrhythmic utilized in prophylaxis of refractory paroxysmal supraventricular tachycardias in pediatric populations. Despite being a highly effective agent, its narrow therapeutic index increases the risk of toxicity and proarrhythmic events, including wide-complex tachycardia. In the absence of direct plasma sampling in the fetus to quantitate flecainide systemic concentrations, clinicians typically make drug dosing decisions from maternal plasma concentrations and QRS duration on maternal ECGs.
View Article and Find Full Text PDFPurpose: The purpose of this study is to identify predictors and correlates of VO2RD in youth with Fontan.
Methods: Cardiopulmonary exercise test data was used from a single center, cross-sectional study of children and adolescents (age, 8-21 yr) with Fontan physiology. The VO2RD was determined using time (s) to <90% of V̇O 2peak and categorized as "low" (≤10 s) or "high" (≥10 s).
The Pediatric Heart Network's Fontan Udenafil Exercise Longitudinal (FUEL) Trial (Mezzion Pharma Co. Ltd., NCT02741115) demonstrated improvements in some measures of exercise capacity and in the myocardial performance index following 6 months of treatment with udenafil (87.
View Article and Find Full Text PDFThis article reports a safe, low-cost, and industrially applicable magnetite supported on activated carbon catalyst that can be magnetically retrieved from the solid and reused multiple times without the need of a regeneration step. The FeO/C catalyst improved the bio-oil yield by 19.7 ± 0.
View Article and Find Full Text PDFBackground: Cardiovascular health scores, such as Life's Simple 7 from the American Heart Association, and the assessment of arterial properties are independently used to determine cardiovascular risk. However, evidence of their association remains scarce, especially in healthy, middle-aged to older populations.
Methods: A healthy sample of the Swiss population aged 50-91 years as part of the COmPLETE cohort study was included.
Background: Grip strength is used to estimate whole-body strength for health surveillance purposes. Explosive strength is considered important, yet economic measures able to detect early deterioration of neuromuscular capabilities are lacking. Whether handgrip maximum rate of force development (GRFD) or whole-body strength tests are better predictors of lower body power than handgrip maximum strength (GF) and their trajectories throughout the life span are unknown.
View Article and Find Full Text PDFFilamentous enzymes have been found in all domains of life, but the advantage of filamentation is often elusive. Some anaerobic, autotrophic bacteria have an unusual filamentous enzyme for CO fixation-hydrogen-dependent CO reductase (HDCR)-which directly converts H and CO into formic acid. HDCR reduces CO with a higher activity than any other known biological or chemical catalyst, and it has therefore gained considerable interest in two areas of global relevance: hydrogen storage and combating climate change by capturing atmospheric CO.
View Article and Find Full Text PDFImprovements in cryo-electron tomography sample preparation, electron-microscopy instrumentations, and image processing algorithms have advanced the structural analysis of macromolecules in situ. Beyond such analyses of individual macromolecules, the study of their interactions with functionally related neighbors in crowded cellular habitats, i.e.
View Article and Find Full Text PDFThe Pharmacogene Variation Consortium (PharmVar) is now providing star (*) allele nomenclature for the highly polymorphic human SLCO1B1 gene encoding the organic anion transporting polypeptide 1B1 (OATP1B1) drug transporter. Genetic variation within the SLCO1B1 gene locus impacts drug transport, which can lead to altered pharmacokinetic profiles of several commonly prescribed drugs. Variable OATP1B1 function is of particular importance regarding hepatic uptake of statins and the risk of statin-associated musculoskeletal symptoms.
View Article and Find Full Text PDF