Stress in the diaphragm, transdiaphragmatic pressure, and diaphragm shape are interrelated by a balance of forces. Using precise in vivo measurements of diaphragm shape and transdiaphragmatic pressure distribution in combination with finite-element analysis (ANSYS), we determined the direction and magnitude of stress in the passive diaphragm at relaxation volume. Lead spheres sutured along musc...

Ahn B, Beharry AW, Frye GS, Judge AR, Ferreira LF. NAD(P)H oxidase subunit p47 is elevated, and p47 knockout prevents diaphragm contractile dysfunction in heart failure. Am J Physiol Lung Cell Mol Physiol 309: L497–L505, 2015. First published July 24, 2015; doi:10.1152/ajplung.00176.2015.—Patients with chronic heart failure (CHF) have dyspnea and exercise intolerance, which are caused in part b...

The use of esophageal recordings of the diaphragm electromyogram (EMG) signal strength to evaluate diaphragm activation during voluntary contractions in humans has recently been criticized because of a possible artifact created by changes in lung volume. Therefore, the first aim of this study was to evaluate whether there is an artifactual influence of lung volume on the strength of the diaphra...

[Purpose] The purpose of this study was to examine effects of diaphragm breathing exercise applied on the basis overload principle on respiratory function. [Subjects and Methods] The subjects of this study were 35 normal adults. They were randomly assigned to two group; the maneuver-diaphragm exercise group and self-diaphragm exercise group. The respiratory function was evaluated using the Card...

In congestive heart failure (CHF), diaphragm weakness is known to occur and is associated with myosin loss and activation of the ubiquitin-proteasome pathway. The effect of modulating proteasome activity on myosin loss and diaphragm function is unknown. The present study investigated the effect of in vivo proteasome inhibition on myosin loss and diaphragm function in CHF rats. Coronary artery l...

Main results 2 trials met the selection criteria: 1 trial compared the Prentif Cavity Rim Cervical Cap (Lamberts Ltd, Oxford, UK) with the Ortho diaphragm (Ortho Pharmaceutical Corporation, Raritan, NJ, USA) (n=1529, 6–24 mo follow up), and 1 trial compared the FemCap cervical cap (rubber manufactured by Hi-Tech Rubber, Anaheim, CA, USA) with the All-Flex diaphragm (Ortho) (n=841, 28 wk follow ...

During the past 10 years, intensive experimental research has focused on the effects of mechanical ventilation on the diaphragm. Whatever the animal species studied, all these studies have consistently shown that mechanical ventilation impaired diaphragm function, resulting in the so-called ventilatorinduced diaphragm dysfunction (VIDD) [1–9]. The development of this effect is rapid and worsens...

We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr₀.₅₂Ti₀.₄₈)O₃ (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC voltage. The curvature of the diaphragm was controlled by applying air pressure to its back. We found that a depolarized flat diaphragm does not initia...

The diaphragm is a sheet of muscle that separates the lungs from the abdomen. When a person takes a deep breath, the dome-shaped diaphragm contracts and flattens. In doing this, the diaphragm pulls air into the lungs. The left diaphragm contains a small hole through which passes the tube-shaped esophagus that carries food and liquid to the stomach. Normally this hole, called a hiatus, is small ...