Background/aims: The lower esophageal sphincter (LES) pressure in humans is asymmetric; the highest pressure and the most significant cholinergic contribution occurs toward the left. The basis of this asymmetry was examined using the cat as a model.
Methods: The LES pressure profile was determined using a manometry catheter with four ports oriented at right angles. The LES was dissected into right and left halves with the latter including a contribution from the oblique gastric sling fibers. Isometric tension responses were studied in vitro.
Results: In vivo, both the initial LES pressure (31.8 +/- 4.0 mm Hg) and the decrease (79.9% +/- 6.4%) after intravenous atropine (100 micrograms/kg) were greatest in the leftward direction. In vitro, both halves of the LES developed similar spontaneous tension, but the increase in tension to carbachol was twofold greater on the left than the right. Eserine increased and atropine decreased initial tension by 25%-30% in both. Strips from either side relaxed in response to electrical stimulation but the response was more complete in strips from the right, whereas sodium nitroprusside produced similar relaxation in both.
Conclusions: Regional differences in the LES pressure and its cholinergic component can be accounted for by differences in the in vitro properties of the LES muscle fiber groups.
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http://dx.doi.org/10.1016/0016-5085(94)90596-7 | DOI Listing |
Gait Posture
January 2025
Groupe de Recherche sur les Affections Neuromusculosquelettiques, Université du Québec à Trois-Rivières, Canada; Department of Human Kinetics, Université du Québec à Trois-Rivières, Canada; Center for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), Quebec, QC, Canada.
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January 2025
Sports Physical Therapy Laboratory, School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Greece. Electronic address:
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View Article and Find Full Text PDFBMC Public Health
January 2025
UMR 1295, Paul Sabatier III University-Inserm, CERPOP: Centre for Epidemiology Research in Population Health, Toulouse, France.
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January 2025
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The most severe form of muscular dystrophy (MD), known as Duchenne MD (DMD), remains an incurable disease, hence the ongoing efforts to develop supportive therapies. The dysregulation of autophagy, a degradative yet protective mechanism activated when tissues are under severe and prolonged stress, is critically involved in DMD. Treatments that harness autophagic capacities therefore represent a promising therapeutic approach.
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Introduction: Infertility has significant implications on health. It affects physical, emotional, and social wellbeing. In Morocco, about 12% of couples or live with infertility.
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