Following receipt of instructions on optimal lower extremity movement pattern, women who demonstrate a moderate quality of movement, as assessed visually during the lateral step-down test, exhibit decreased ankle dorsiflexion range of motion compared to women with a good quality of movement. Clinicians should consider evaluating ankle dorsiflexion range of motion when observing an altered lower extremity movement pattern during the lateral step-down test.

The emergence of catalysis in a noncatalytic protein scaffold is a rare, unexplored event. Chalcone isomerase (CHI), a key enzyme in plant flavonoid biosynthesis, is presumed to have evolved from a nonenzymatic ancestor related to the widely distributed fatty-acid binding proteins (FAPs) and a plant protein family with no isomerase activity (CHILs). Ancestral inference supported the evolution of CHI from a protein lacking isomerase activity. Further, we identified four alternative founder mutations, i.e., mutations that individually instated activity, including a mutation that is not phylogenetically traceable. Despite strong epistasis in other cases of protein evolution, CHI's laboratory reconstructed mutational trajectory shows weak epistasis. Thus, enantioselective CHI activity could readily emerge despite a catalytically inactive starting point. Accordingly, X-ray crystallography, NMR, and molecular dynamics simulations reveal reshaping of the active site toward a productive substrate-binding mode and repositioning of the catalytic arginine that was inherited from the ancestral fatty-acid binding proteins.

Ankle DF ROM should be assessed when patients with PFP demonstrate a lower quality of movement during a lateral step-down test. Lower hip muscle strength may be associated with lower quality of movement among patients with relatively greater ankle DF ROM.

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First and foremost: Margaret Dayhoff's 1966 hypothesis on the origin of proteins is now an accepted model for the emergence of large, globular, functional proteins from short, simple peptides. However, the fundamental question of how the first protein(s) emerged still stands. The tools and hypotheses pioneered by Dayhoff, and the over 65 million protein sequences and 12 000 structures known today, enable those who follow in her footsteps to address this question.

4Study Design: Test-retest reliability study. Objective: To determine interrater reliability of the modified scapular assistance test (SAT). The modified SAT is designed to assess the contribution of scapular motion to shoulder pain. Background: Abnormal scapular motion has been implicated in different shoulder disorders. However, there is a lack of clinical evaluation tools to assess the scapular component of shoulder dysfunction. Methods and Measures: Forty-six subjects who were referred to physical therapy for treatment of various shoulder pathologies were recruited for this study. The modified SAT was performed on each participant by 2 different examiners. Percent agreement and kappa coefficient were utilized to determine interrater reliability of the modified SAT. Results: The kappa coefficient and percent agreement were .53 and 77%, respectively, when the test was performed in the scapular plane, and .62 and 91%, respectively, when the test was performed in the sagittal plane. Conclusions: The modified SAT possesses acceptable interrater reliability for clinical use.

Study Design Controlled laboratory study. Background Altered hip and knee kinematics have been associated with several knee disorders, including anterior cruciate ligament tear, patellofemoral pain, and iliotibial band syndrome. Limited ankle dorsiflexion (DF) range of motion (ROM), which has been linked with some of these disorders, has also been associated with altered knee kinematics. Objective To explore the association of ankle DF ROM with hip and knee kinematics during a step-down task. Methods Thirty healthy participants underwent a 3-D analysis of hip and knee kinematics during a lateral step-down test, followed by measurement of ankle DF ROM in weight bearing (WB) and non-weight bearing (NWB). Participants were dichotomized using the median values into low- and high-DF subgroups within both WB and NWB. Hip and knee kinematics were compared between the low- and high-DF subgroups. Results Participants in the low-DF subgroups exhibited greater peak hip adduction (WB, P = .02; NWB, P<.01) and greater peak knee external rotation (WB, P = .02; NWB, P<.01) compared with participants in the high-DF subgroups. In addition, participants in the low-DF WB subgroup exhibited decreased peak knee flexion compared with participants in the high-DF WB subgroup (P<.01). Conclusion Individuals with lower ankle DF ROM exhibited hip and knee kinematics previously associated with several knee disorders, suggesting that this impairment may be involved in the pathogenesis of the same disorders. Assessment of ankle DF ROM may be useful as part of a preparticipation screening. Furthermore, deficits in ankle DF ROM may need to be addressed in individuals with altered movement patterns. J Orthop Sports Phys Ther 2016;46(11):-1. Epub 29 Sep 2016. doi:10.2519/jospt.2016.6621.

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