EMG Analysis of Lower Extremity Muscle Activity during Wall Slides with Varying Foot Positions

Knee injuries are among the most common injuries seen in a physical therapy clinic. Nearly all rehabilitation programs following a knee injury involve quadriceps muscle strengthening. One popular and safe method of quadriceps strengthening often used is the wall slide. There is, however, debate and little research indicating whether or not changing the foot position used during wall slides alters the muscle activity during this exercise. The purpose of this study was to provide a better understanding of the muscle activity during wall slides with feet in various positions so that more accurate rehabilitation protocols may be developed in the physical therapy clinic. Thirty participants without previous history of knee pathologies were recruited to participate in this study. The subjects were asked to perform a series of 5 wall slides in 3 different foot positions. These positions were indicated by placing marks on non-skid floor mats. Foi the first position, subjects were asked to line up their second toe and heal with a line perpendicular to the wall. Position 2 was performed by having the subjects rotate their feet so that their second toe lined up with a line 30 degrees inward from the first line with resultant hip internal rotation. The third position was obtained in the same way as the second position, with the only difference being that rotation was done in an outward direction. These 3 positions were referred to as neutral rotation, 30 degrees of internal rotation, and 30 degrees of external rotation. The order of these positions was randomly selected and the wall slides were performed to a knee flexion angle of 45 degrees. Electromyographic activity was recorded for the rectus femoris, vastus lateralis, vastus medialis, biceps femoris, gastrocnemius, and anterior tibialis muscles of the subjects\u27 dominant leg. The results of this study indicated that there is no significant difference in EMG activity of the quadriceps muscles (vastus lateralis, vastus medialis, and rectus femoris) across foot positions. The results did, however, indicate a significant difference in EMG activity across foot positions for the anterior tibialis, biceps femoris, and gastrocnemius muscle. These results suggested that clinicians may need to address foot position during wall slides when these muscles are involved following a knee injury. The results also suggested that the patient\u27s foot position during a wall slide is not an important factor to consider when developing a rehabilitation program for quadriceps muscle strengthening following a knee injury. Allowing the patient to perform the wall slide in a position of comfort should then be the clinician\u27s main concern

Expression of Groucho/TLE proteins during pancreas development

<p>Abstract</p> <p>Background</p> <p>The full-length mammalian homologs of <it>groucho</it>, Tle1, 2, 3, and 4, act as transcriptional corepressors and are recruited by transcription factors containing an eh1 or WRPW/Y domain. Many transcription factors critical to pancreas development contain a Gro/TLE interaction domain and several have been shown to require Gro/TLE interactions for proper function during neuronal development. However, a detailed analysis of the expression patterns of the Gro/TLE proteins in pancreas development has not been performed. Moreover, little is known about the ability of Gro/TLE proteins to interact with transcription factors in the pancreas.</p> <p>Results</p> <p>We describe the expression of Gro/TLE family members, and of 34 different transcription factors that contain a Gro/TLE interaction motif, in the pancreas utilizing nine SAGE libraries created from the developing and adult pancreas, as well as the <it>GenePaint </it>database. Next, we show the dynamic expression of <it>Tle1</it>, <it>2</it>, <it>3</it>, <it>4, 5 </it>and <it>6 </it>during pancreas development by qRT-PCR. To further define the cell-type specificity of the expression of these proteins we use immunofluorescence to co-localize them with Pdx1 at embryonic day 12.5 (E12.5), Ngn3 at E14.5, Pdx1, Nkx2-2, Insulin, Glucagon, Pancreatic polypeptide and Somatostatin at E18.5, as well as Insulin and Glucagon in the adult. We then show that Tle2 can interact with Nkx2-2, Hes1, Arx, and Nkx6-1 which are all critical factors in pancreas development. Finally, we demonstrate that Tle2 modulates the repressive abilities of Arx in a β-cell line.</p> <p>Conclusion</p> <p>Although Tle1, 2, 3, and 4 show overlapping expression in pancreatic progenitors and in the adult islet, the expression of these factors is restricted to different cell types during endocrine cell maturation. Of note, Tle2 and Tle3 are co-expressed with Gro/TLE interaction domain containing transcription factors that are essential for endocrine pancreas development. We further demonstrate that Tle2 can interact with several of these factors and that Tle2 modulate Arx's repressive activity. Taken together our studies suggest that Gro/TLE proteins play a role in the repression of target genes during endocrine cell specification.</p

Identification of transcripts with enriched expression in the developing and adult pancreas

The expression profile of different developmental stages of the murine pancreas and predictions of transcription factor interactions, provides a framework for pancreas regulatory networks and development

A global alliance declaring war on cassava viruses in Africa

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