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Dive into the research topics where Gulchin A. Ergun is active.

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Featured researches published by Gulchin A. Ergun.


Gastroenterology | 1992

Pharyngeal Clearance During Swallowing: A Combined Manometric and Videofluoroscopic Study

Peter J. Kahrilas; Jerilyn A. Logemann; Shezhang Lin; Gulchin A. Ergun

The deglutitive pharyngeal contraction was analyzed using simultaneous videofluoroscopic and manometric studies of eight volunteers. Anterior, posterior, and longitudinal movements of the pharyngeal surfaces, relative to the cervical vertebrae, were measured during swallows of 5 and 10 mL of liquid barium. Profound pharyngeal shortening during bolus transit through the pharynx eliminated access to the larynx and elevated the upper esophageal sphincter to within 1.5 cm of the retrolingual pharynx. Bolus head movement through the pharynx preceded the propagated pharyngeal contraction and registered manometrically as a slight intrabolus pressure before the major pressure complex. Contraction in the horizontal plane began after bolus head transit and culminated with stripping of the bolus tail through the pharynx. Prolonged upper sphincter opening with the larger-volume swallows resulted from a delayed onset rather than altered propagation of the horizontal pharyngeal contraction. It is concluded that the propagated pharyngeal contraction facilitates pharyngeal clearance but has a minimal role in the process of bolus propulsion during swallowing. The propagated contraction works in concert with profound pharyngeal shortening to minimize hypopharyngeal residue after a swallow.


Gastroenterology | 1993

Deglutitive tongue action: Volume accommodation and bolus propulsion

Peter J. Kahrilas; Shezhang Lin; Jerilyn A. Logemann; Gulchin A. Ergun; Frank Facchini

BACKGROUND Swallow function is best analyzed in components because discrete component failure may be compensated for with devised maneuvers, postures, or biofeedback techniques. The present investigation examined normal deglutitive tongue function. METHODS Biplane videofluoroscopy synchronized with intraluminal manometry was performed in eight volunteers. Tongue surface motion was characterized as centripetal or centrifugal along seven equiangular rays emanating from the tongue center during 1-, 5-, 10-, and 20-mL swallows. RESULTS The tongue perimeter remained in contact with the alveolar ridge while the central groove exhibited centripetal and subsequent centrifugal motion that, in conjunction with the pharyngeal walls, created an oropharyngeal propulsive chamber and then expelled that chambers contents into the hypopharynx. Intrabolus propulsive pressure was generated when the initially expansive propulsive chamber volume contracted to the test bolus volume. Because pharyngeal chamber action cycle timing was relatively constant among bolus volumes, vigorous expulsion occurred with large volumes but relatively delayed, sluggish expulsion occurred with smaller volumes. CONCLUSIONS Deglutitive tongue functions include bolus containment, volume accommodation, and the major contributor to bolus propulsion.


Gastroenterology | 1993

Shape, volume, and content of the deglutitive pharyngeal chamber imaged by ultrafast computerized tomography.

Gulchin A. Ergun; Peter J. Kahrilas; Shezhang Lin; Jerilyn A. Logemann; James M. Harig

BACKGROUND Conventional radiographic techniques image only the silhouettes of the deglutitive pharyngeal chamber. This study aimed to accurately image the horizontal plane shape and content of the pharynx during swallowing. METHODS Dynamic computerized tomography images of the pharynx were obtained at the rate of 17 per second during swallowing. Multiple adjacent levels were imaged in eight subjects and a single level was scanned in four subjects during swallows of varied volume. Images were analyzed for area, volume, and the bolus fraction of the deglutitive pharyngeal chamber. RESULTS The deglutitive chamber enlarged to approximately 24 mL (during tongue loading) compared with a preswallow pharyngeal volume averaging 15 mL. Throughout the 10 mL swallows, the bolus occupied less than 30% of the lumen regardless of axial level. The bolus fraction of the deglutitive chamber increased with swallow volume, as did the dimensions of the upper esophageal sphincter and the bolus velocity through the upper esophageal sphincter. CONCLUSIONS The deglutitive pharyngeal chamber was typically approximately 15 mL > the bolus volume, implying that an obligatory 15 mL of air was swallowed under these test conditions. Most swallowed air originated as air trapped within the pharynx and larynx as the oropharynx was sealed from above and below.


The American Journal of Gastroenterology | 1998

Lower esophageal sphincter relaxation characteristics using a sleeve sensor in clinical manometry

Guoxiang Shi; Gulchin A. Ergun; Michael Manka; Peter J. Kahrilas

Objective:We undertook this study to determine the characteristics of swallow-induced lower esophageal sphincter (LES) relaxation in the setting of clinical manometry using a standardized methodology.Methods:We reviewed 170 manometric recordings performed using a perfused manometric assembly with a sleeve sensor and a computer polygraph. Patients were categorized as patient controls, gastroesophageal reflux disease (GERD), diffuse esophageal spasm (DES), or achalasia. Tracing were semiautomatically analyzed for basal LES pressure, LES pressure during deglutitive relaxation (relaxation LES pressure), duration of LES relaxation, timing of LES relaxation, and the success rate of primary peristalsis.Results:Forty-six patient controls, 93 with GERD, five with DES, and 26 with achalasia were identified. GERD and achalasia patients had lower or higher basal LES pressures than patient controls, respectively. Compared with patient controls, achalasia patients had higher relaxation LES pressures, lower percent LES relaxation, and shorter durations of LES relaxation. The best single measure for distinguishing achalasia was the relaxation LES pressure; using the 95th percentile value of patient controls (12 mm Hg) as the upper limit of normal, its sensitivity and positive predictive value for the diagnosis of achalasia were 92% and 88%, respectively. Coupled with the finding of aperistalsis, a relaxation LES pressure ≥10 mm Hg achieved 100% sensitivity and positive predictive value among these patients.Conclusion:Sleeve sensor recording is a practical method for clinical manometry that reliably records LES relaxation characteristics and is amenable to both a standardized manometry protocol and a semiautomated analysis routine. Relaxation LES pressure has a high diagnostic value for achalasia.


The American Journal of Gastroenterology | 2003

Avoiding infliximab in the treatment of Crohn's disease in patients with multiple sclerosis

Shardul A. Nanavati; Gulchin A. Ergun; Jim T. Schwartz

Avoiding infliximab in the treatment of Crohns disease in patients with multiple sclerosis


Archive | 2002

Esophageal Muscular Anatomy and Physiology

Gulchin A. Ergun; Peter J. Kahrilas

The major function of the esophagus is to transport food from the mouth to the stomach while preventing retrograde movement of gastric contents. It is in essence a hollow muscular tube that is closed at the proximal portion by the upper esophageal sphincter (UES) and by the lower esophageal sphincter (LES) at the bottom. The pharynx and the proximal esophagus contain striated muscle controlled by the swallowing center in the brain stem through the vagus nerves. The lower two thirds of the esophagus contains smooth muscle with peristalsis controlled primarily by an intrinsic neural network located between the longitudinal and circular muscle layers, and is modulated by central mechanisms in the swallowing center. Proximal esophageal function is complex because the oral cavity and pharynx must necessarily serve multiple functions, not only as a food conduit, but also as a respiratory conduit, thereby requiring precise control and efficient coordination of swallowing and respiration.


Gastroenterology | 2003

Expression of the high mobility group proteins HMGI(Y) correlates with malignant progression in Barrett metaplasia

Xueyun Chen; Juan Lechago; Atilla Ertan; Gulchin A. Ergun; Ray Verm; Margaret Bridges; Craig Johnson; Karen Woods; Frank V. Meriano; Minni Chirala; Mamoun Younes

Expression of the high mobility group proteins HMGI(Y) has been shown to be a marker of malignancy in thyroid and pancreatic lesions and to correlate significantly with malignant progression in the colon. The aim of this study was to determine whether HMGI(Y) expression is associated with malignant progression in Barretts metaplasia (BM). Immunoperoxidase staining for HMGI(Y) was performed on sections of formalin-fixed paraffin-embedded endoscopic esophageal biopsies from 42 patients with BM. These consisted of 19 biopsies negative for dysplasia (ND), 16 with low-grade dysplasia (LGD)/indeterminate for dysplasia (IND), and 7 with high-grade dysplasia (HGD)/adenocarcinoma (CA). The percentage of positive cells was recorded, and nuclear HMGI(Y) immunoreactivity in >10% of the cells was considered positive. Statistical analysis was performed using Fishers exact test. Positive HMGI(Y) staining was detected in 2 of 19 (11%) cases ND, 5 of 16 (30%) LGD/IND cases, and 7 of 7 (100%) HGD/CA cases. Biopsies with HGD/CA were significantly more likely to be positive for HMGI(Y) than biopsies ND (P < 0.0001) or with LGD/IND (P = 0.0046). We conclude that HMGI(Y) expression is significantly associated with malignant progression in BM. Additional studies are needed to determine whether BM biopsies that are ND or LGD/IND and positive for HMGI(Y) are more likely to progress to adenocarcinoma.


Gastroenterology | 1996

Esophageal bolus transit imaged by ultrafast computerized tomography

Philippe Pouderoux; Gulchin A. Ergun; Shezhang Lin; Peter J. Kahrilas


The American Journal of Gastroenterology | 1996

Clinical applications of esophageal manometry and pH monitoring.

Gulchin A. Ergun; Peter J. Kahrilas


Diseases of The Esophagus | 1993

Interpretation of pharyngeal manometric recordings: Limitations and variability

Gulchin A. Ergun; Peter J. Kahrilas; Jerilyn A. Logemann

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Shezhang Lin

Northwestern University

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Ali Raza

Houston Methodist Hospital

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Atilla Ertan

University of Texas Health Science Center at Houston

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Guoxiang Shi

Northwestern University

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Jim T. Schwartz

Baylor College of Medicine

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Karen Woods

Baylor College of Medicine

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