Publications by authors named "Ann Ouyang"

Background Our aim was to assess the clinical presentation and outcomes of patients with a manometric diagnosis of esophagogastric junction outflow obstruction (EGJOO) using standardized symptom surveys and comparison to a cohort who were referred for manometry but who had a normal study. Methods We followed a cohort of adult patients without a mechanical obstruction who underwent high-resolution manometry at our medical center from 9/12/19 to 10/4/21 for 16 months. Results Thirty-seven patients with EGJOO (age: 60.

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Introduction: Hypoalgesic inflammatory bowel disease (IBD) may provide critical insights into human abdominal pain. This condition was previously associated with homozygosity for a polymorphism (rs6795970, A1073V; 1073 val/val ) related to Na v 1.8, a voltage-gated sodium channel preferentially expressed on nociceptors.

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Pain is a major issue in healthcare throughout the world. It remains one of the major clinical issues of our time because it is a common sequela of numerous conditions, has a tremendous impact on individual quality of life, and is one of the top drivers of cost in medicine, due to its influence on healthcare expenditures and lost productivity in those affected by it. Patients and healthcare providers remain desperate to find new, safer and more effective analgesics.

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Background: The Chicago Classification version 4.0 (CCv4.0) of ineffective esophageal motility (IEM) is more stringent than the Chicago Classification version 3.

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This article was migrated. The article was marked as recommended. This study examined the interaction between work role overload, work-to-family conflict, and departmental/division culture conducive to women's academic success.

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Tissue engineering constructs to treat intervertebral disc degeneration must adapt to the hypoxic and inflammatory degenerative disc microenvironment. The objective of this study was to determine the effects of two key design factors, cell type and cell configuration, on the regenerative potential of nucleus pulposus cell (NPC) and mesenchymal stem cell (MSC) constructs. Anabolic and catabolic activity was quantified in constructs of varying cell type (NPCs, MSCs, and a 50:50 co-culture) and varying configuration (individual cells and micropellets).

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The following discussion on the physiology of the esophagus includes commentaries on the function of the muscularis mucosa and submucosa as a mechanical antireflux barrier in the esophagus; the different mechanisms of neurological control in the esophageal striated and smooth muscle; new insights from animal models into the neurotransmitters mediating lower esophageal sphincter (LES) relaxation, peristalsis in the esophageal body (EB), and motility of esophageal smooth muscle; differentiation between in vitro properties of the lower esophageal circular muscle, clasp muscle, and sling fibers; alterations in the relationship between pharyngeal contraction and relaxation of the upper esophageal sphincter (UES) in patients with dysphagia; the mechanical relationships between anterior hyoid movement, the extent of upper esophageal opening, and aspiration; the application of fluoroscopy and manometry with biomechanics to define the stages of UES opening; and nonpharmacological approaches to alter the gastroesophageal junction (GEJ).

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Oropharyngeal dysphagia (OD) is a swallowing disorder caused by congenital abnormalities and structural damage and disease-associated damage of the oral cavity, pharynx, and upper esophageal sphincter. Patients with OD lack the protective mechanisms necessary for effective swallowing, exhibiting difficulty controlling food in the mouth and initiating a swallow, leading to choking, coughing, and nasal regurgitation. OD is a major risk factor for malnutrition, dehydration, and aspiration pneumonia.

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Background And Aims: Cholecystokinin-cholescintigraphy (CCK-CS) provides a physiologic, noninvasive, and quantitative method for assessing gallbladder contraction and calculation of a gallbladder ejection fraction (GBEF). At present, it is used most commonly to identify patients with suspected functional gallbladder disorder. However, the methodology of CCK infusion and normal values differ markedly among imaging centers.

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Eosinophilic esophagitis is characterized by increased infiltration and degranulation of eosinophils in the esophagus. Whether eosinophil-derived cationic proteins regulate esophageal sensory nerve function is still unknown. Using synthetic cationic protein to investigate such effect, we performed extracellular recordings from vagal nodose or jugular neurons in ex vivo esophageal-vagal preparations with intact nerve endings in the esophagus.

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Background & Aims: Cholecystokinin-cholescintigraphy (CCK-CS) provides a physiologic, noninvasive, and quantitative method for assessing gallbladder contraction and calculation of a gallbladder ejection fraction (GBEF). At present, it is used most commonly to identify patients with suspected functional gallbladder disorder. However, the methodology of CCK infusion and normal values differ markedly among imaging centers.

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Sensitization of esophageal sensory afferents by inflammatory mediators plays an important role in esophageal nociception. We have shown esophageal mast cell activation induces long-lasting mechanical hypersensitivity in vagal nodose C-fibers. However, the roles of mast cell mediators and downstream ion channels in this process are unclear.

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Bradykinin (BK) activates sensory nerves and causes hyperalgesia. Transient receptor potential A1 (TRPA1) is expressed in sensory nerves and mediates cold, mechanical, and chemical nociception. TRPA1 can be activated by BK.

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Antigen challenge in sensitized guinea pig esophagus in vitro induces mast cell degranulation and histamine release. This study tests the hypothesis that antigen inhalation in vivo induces infiltration of the esophageal epithelium by mast cells and eosinophils via a histamine pathway. Actively sensitized guinea pigs were exposed to inhaled 0.

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The classification of gastrointestinal (GI) motility and functional gastrointestinal disorders is in a state of transition. Functional GI disorders are classified by their symptom complex, and the epidemiology of these conditions is based on symptom surveys. In contrast, GI motility disorders are classified by results of GI motility testing; the epidemiology of these conditions is often derived from tertiary care centers.

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Aim: To evaluate the effectiveness of a holistic acupuncture approach on nausea, pain, bloating and electrogastrogram (EGG) parameters in patients with intractable symptoms.

Methods: Twelve patients with no or mild nausea (those without nausea had bloating or pain) and 10 with a history of moderate to severe nausea were referred for acupuncture. All underwent an EGG and were treated at acupuncture points PC6, SP4 and DU20.

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Several esophageal pathologies are associated with an increased number of mast cells in the esophageal wall. We addressed the hypothesis that activation of esophageal mast cells leads to an increase in the excitability of local sensory C fibers. Guinea pigs were actively sensitized to ovalbumin.

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The irritable bowel syndrome (IBS) is found more commonly in women than men. It is more prevalent in patients with chronic fatigue syndrome, fibromyalgia, and chronic pelvic pain, all syndromes characterized by pain and found predominantly in women. This article reviews evidence for a role of biological sex factors and gender on the pathways mediating visceral pain.

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Aim: To investigate the pathway (s) mediating rat antral circular smooth muscle contractile responses to the cholinomimetic agent, bethanechol and the subtypes of muscarinic receptors mediating the cholinergic contraction.

Methods: Circular smooth muscle strips from the antrum of Sprague-Dawley rats were mounted in muscle baths in Krebs buffer. Isometric tension was recorded.

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Objectives: The management strategies used when patients requiring long-term anticoagulation need endoscopic procedures vary considerably. Two commonly used approaches are a "heparin window" strategy in the inpatient setting and, more recently, a "switch to low molecular weight heparin (LMWH)" strategy for elective procedures. The aim of this study was to determine whether an initial diagnostic endoscopy (visualization only) is a cost-effective strategy in these patients.

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