Introgression from non-native species unveils a hidden threat to the migratory Neotropical fish Prochilodus hartii

Abstract

Background: The patellofemoral joint is an important source of pain in knee osteoarthritis. Most biomechanical research in knee osteoarthritis has focused on the tibiofemoral joint during level walking. It is unknown what happens during stair negotiation in patients with patellofemoral joint osteoarthritis, a task commonly increasing pain. Conservative therapy for patellofemoral joint osteoarthritis includes the use of a sleeve knee brace. We aimed to examine the effect of a sleeve knee brace on knee biomechanics during stair negotiation in patellofemoral joint osteoarthritis patients. Methods: 30 patellofemoral joint osteoarthritis patients (40-70 years) ascended and descended an instrumented staircase with force plates under two conditionswearing a Lycra flexible knee support (Bioskin Patellar Tracking Q Brace) and no brace (control condition). Knee joint kinematics (VICON) and kinetics were recorded. Findings: During stair ascent, at the knee, the brace significantly reduced the maximal flexion angle (2.7 0 , P = 0.002), maximal adduction angle (2.0 0 , P = 0.044), total sagittal range of motion (2.0 0 , P = 0.008), total frontal range of motion (1.7 0 , P = 0.023) and sagittal peak extension moment (0.05 Nm/kg, P = 0.043) compared to control. During stair descent, at the knee, the brace significantly reduced the maximal flexion angle (1.8 0 , P = 0.039) and total sagittal range of motion (1.5 0 , P = 0.045) compared to control. Interpretation: The small changes in knee joint biomechanics during stair negotiation observed in our study need to be investigated further to help explain mechanisms behind the potential benefits of a sleeve knee brace for painful patellofemoral joint osteoarthritis.

Little Divergence Among Mitochondrial Lineages of Prochilodus (Teleostei, Characiformes)

“…Prochilodus vimboides (lineage 1), for example, splits from the most recent common ancestor of all other Prochilodus , although the biogeographic implications for this result still requires a more detailed, time-calibrated analysis of the Prochilodontidae. Other example is the structuring of P. harttii (lineage 4) and P. argenteus (lineage 5), evidencing distinct genetic lineages even with a recent evidence of hybridization (Sales et al, 2018 ). In contrast with the molecular phylogeny, results indicate that P. mariae is an exclusive cluster, suggesting inconsistencies in the phylogenetic placement of the species (Castro and Vari, 2004 ; Melo et al, 2016a ).…”

“…Prochilodontids represent a good model to address such questions because much research on population genetics and phylogeography have provided valuable intraspecific genetic information (Sivasundar et al, 2001 ; Turner et al, 2004 ; Hatanaka et al, 2006 ; Carvalho-Costa et al, 2008 ; Melo et al, 2013 ; Rueda et al, 2013 ; Ferreira et al, 2017 ; Machado et al, 2017 ; Sales et al, 2018 ). Furthermore, recent barcoding studies in focal regions (i.e., using endemic species) have generated a robust mitochondrial database for Prochilodus (e.g., Carvalho et al, 2011 ; Rosso et al, 2012 ; Pereira et al, 2013 ; Chagas et al, 2015 ; Díaz et al, 2016 ) that, if combined, might be useful for species-level comparisons.…”

Occurrence of Serrassalmidae Hybrid Fish in the Amazon River Basin, Brazil

“…This can lead to unsuccessful crosses with parental species, resulting in unviable descendants, or presenting agonistic behavior as territorial dispute, interfering in the reproductive dynamics of pure species (Toledo-Filho et al 1994). Moreover, they may promote backcrossing or genetic introgression in the original ichthyofauna, an observation corroborated by Prado et al (2017) and Sales et al (2018).…”

A network meta‐analysis of threats to South American fish biodiversity

“…Tilapiine hybrids, the "tilapia for aquaculture", and other hybrids have evolutive advantages such as rapid growth, high parental care, resistance to diseases and tolerance to adverse environmental conditions (Watanabe et al, 2002). Even if hybridization can serve as an alternative for the aquaculture (Saint-Paul, 2017;Valladão et al, 2018), hybrids of native species should not be considered native species, but dangerous non-natives (Occhi, Faria, & Vitule, 2017) with evolutive advantages and conspicuous impacts over the native congeners (Hashimoto et al, 2012;Sales, Pessali, Andrade Neto, & Carvalho, 2018).…”