Endoscopic pyloric suturing to facilitate weight loss: a canine model.

Background: More than 66% of adults in United States are overweight or obese.

Objective: To decrease gastric emptying and cause early and prolonged satiety by endoscopically narrowing the gastric pylorus.

Design: Thirteen dogs were randomized into 3 groups (suture, sham, and control).

Induced opening of the gastroesophageal junction occurs at a lower gastric pressure in gerd patients and in hiatal hernia subjects than in normal control subjects.

Purpose. To determine intragastric pressure threshold for inducing gastroesophageal junction (GEJ) opening in normal control subjects with and without hiatal hernia, and in patients with gastroesophageal reflux disease. Methods.

Effect of atilmotin, a motilin receptor agonist, on esophageal, lower esophageal sphincter, and gastric pressures.

Background: Motilin, an endogenous gastrointestinal (GI) hormone, increases upper gastrointestinal tract motility and is associated with phase III of the gastric migrating motor complex. The motilin receptor agonist, atilmotin, at doses of 6, 30 or 60 microg intravenously (IV), increases the early phase of gastric emptying. Prior studies at higher doses of 100-450 microg IV demonstrated that some subjects developed noncardiac chest pain.

Minimally invasive measurement of esophageal variceal pressure and wall tension (with video).

Background: There is no simple method to measure intravariceal pressure in patients with esophageal varices.

Objective: Our purpose was to develop a new noninvasive technique to measure resting intravariceal pressure and wall tension.

Design: A model was developed.

A missing sphincteric component of the gastro-oesophageal junction in patients with GORD.

It was recently shown that the tonic pressure contribution to the high-pressure zone of the oesophago-gastric segment (OGS) contains the contributions from three distinct components, two of which are smooth muscle intrinsic sphincter components, a proximal and a distal component [J Physiol 2007; 580.3: 961]. The aim of this study was to compare the pressure contributions from the three sphincteric components in normal subjects with those in gastro-oesophageal reflux disease (GORD) patients.

Acoustic liver biopsy using endoscopic ultrasound.

Background: Transabdominal ultrasound cannot be used to quantitate fibrosis in patients with cirrhosis because of variability in the abdominal wall thickness and variability in the components of the abdominal wall (fat versus muscle). Endoscopic ultrasound through the gastric wall is always at a constant distance, approximately 3 mm, away from the liver when the transducer is just below the gastroesophageal junction, thereby eliminating this variability.

Purpose: To differentiate between cirrhotic and noncirrhotic liver using endoluminal ultrasound.

Tonic and phasic pyloric activity in response to CCK-octapeptide.

Background: The purpose of this study was to determine whether a high-resolution solid-state catheter system could detect regional pressure changes within the antrum and pylorus in response to CCK-octapeptide.

Methods: Subjects received a 30 min infusion of CCK-octapeptide at either 0.02 or 0.

New observations on the gastroesophageal antireflux barrier.

The use of high-frequency ultrasound transducers combined with manometry in the gastrointestinal (GI) tract has yielded important findings concerning the anatomy, physiology, and pathophysiology of the high-pressure zone of the gastroesophageal junction and the sphincteric muscles within. These transducers have made previously invisible portions of the GI tract accessible to investigation. Three distinct high-pressure zones have been identified and correlated with anatomic structures: the extrinsic sphincter (crural diaphragm) and the two components of the intrinsic sphincter (an upper LES and a lower LES [the gastric sling fiber/clasp fiber complex]).

High-resolution solid-state manometry of the antropyloroduodenal region.

Manometric recording from the pyloric channel is challenging and is usually performed with a sleeve device. Recently, a solid-state manometry system was developed, which incorporates 36 circumferential pressure sensors spaced at 1-cm intervals. Our aim was to use this system to determine whether it provided useful manometric measurements of the pyloric region.

Three-dimensional US volume analysis of gastric pseudotumors in a porcine model.

Background: Tumor burden is difficult to estimate by endoscopy and conventional EUS.

Objective: The purpose of this study was to determine the accuracy and the reliability of a new 3-dimensional (3D) EUS system in a pseudotumor model (Olympus EUS EXERA EU-M60).

Design: A pseudotumor model was developed in a porcine stomach.

Use of endoluminal ultrasound to evaluate gastrointestinal motility.

The use of high-frequency ultrasound transducers in the gastrointestinal tract (GI) has already yielded remarkable findings concerning the anatomy, physiology and pathophysiology of the GI tract and of various motility disorders. These transducers have made completely invisible portions of the GI tract (the longitudinal smooth muscle, muscles of the upper esophageal sphincter, components of the gastroesophageal junction high-pressure zone, and the muscle of the anal sphincter complex) accessible to investigation. Use of simultaneous ultrasound and manometry has allowed the exploration of the normal physiology of peristaltic contraction.

Muscle shortening along the normal esophagus during swallowing.

Longitudinal shortening of the esophagus during peristaltic contraction has been previously analyzed globally using spaced mucosal clips. This method gives a relatively crude measurement. In this study, local longitudinal shortening (LLS) was evaluated using simultaneous high-resolution endoluminal ultrasound (HREUS) and manometry based on basic principles of muscle mechanics.

Risk of esophageal variceal bleeding based on endoscopic ultrasound evaluation of the sum of esophageal variceal cross-sectional surface area.

Objective: The aim of this study was to evaluate the risk of future variceal bleeding, based on the endoscopic ultrasound measurement of the sum of the cross-sectional surface area (CSA) of all of the esophageal varices in the distal esophagus.

Methods: Twenty-eight patients with portal hypertension and esophageal varices, but no prior history of variceal bleeding, were evaluated using endoscopic ultrasound (20-MHz ultrasound probe, Microvasive, Boston, MA; Olympus, Tokyo, Japan). The entire esophagus was imaged, and an image was selected at a point where the varices appeared the largest.

Intracellular localization of processing events in human surfactant protein B biosynthesis.

Surfactant protein B (SP-B) is essential to the function of pulmonary surfactant and to alveolar type 2 cell phenotype. Human SP-B is the 79-amino acid product of extensive post-translational processing of a 381-amino acid preproprotein. Processing involves modification of the primary translation product from 39 to 42 kDa and at least 3 subsequent proteolytic cleavages to produce the mature 8-kDa SP-B.