Diffuse Esophageal Narrowing in Eosinophilic Esophagitis: A Barium Contrast Study.

BACKGROUND: Patients with eosinophilic esophagitis (EoE) present with mechanical type dysphagia. Barium esophagrams occasionally demonstrate focal strictures or multiple concentric rings. Diffuse narrowing has also been reported but may be difficult to recognize because of lack of normative data. AIM: The aim of this study is to assess esophageal diameters at multiple sites in healthy controls in comparison with EoE patients. METHODS: A standardized barium swallow was performed in 22 healthy male volunteers without esophageal symptoms and compared with 10 untreated EoE patients. A radiopaque ruler attached at the subject's back was used to measure maximal esophageal diameter at three esophageal sites by a blinded observer. Peak intraepithelial eosinophil counts and Mayo Dysphagia Questionnaire scores were correlated to esophageal diameters in EoE patients. RESULTS: Two of 10 EoE patients had areas of focal narrowing on barium Xray. Esophageal diameters were significantly less at all three esophageal sites in EoE patients compared with controls. Using a total esophageal diameter score (i.e., sum of the three diameters) to establish the 95th percentile for minimal diameter in controls, four of 10 EoE patients fell below the normal range. There was no significant correlation between esophageal diameters, peak eosinophil counts and any of the Mayo Dysphagia Questionnaire severity scores. CONCLUSION: Patients with EoE have a diffusely narrow esophagus in comparison to healthy controls, and this abnormality may not be appreciated without using appropriate normative data.

Eastern Canadian Colorectal Cancer Consensus Conference 2017.

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2017 was held in St. John's, Newfoundland and Labrador, 28-30 September. Experts in radiation oncology, medical oncology, surgical oncology, and cancer genetics who are involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics in the management of gastric, rectal, and colon cancer, including ■ identification and management of hereditary gastric and colorectal cancer (crc);■ palliative systemic therapy for metastatic gastric cancer;■ optimum duration of preoperative radiation in rectal cancer-that is, short- compared with long-course radiation;■ management options for peritoneal carcinomatosis in crc;■ implications of tumour location for treatment and prognosis in crc; and■ new molecular markers in crc.

L-type Ca(2+) channel expression along feline smooth muscle oesophagus.

Muscle from the proximal smooth muscle (SM) oesophagus of the cat demonstrates contractions of greater amplitude and greater sensitivity to cholinergic stimulation than muscle from the distal SM oesophagus. In the light of the central role of calcium influx in SM contractility, we hypothesized that regional differences in oesophageal contractility may be associated with differential expression of L-type calcium channels (L(Ca)) along the SM oesophagus. L(Ca) expression was compared between proximal and distal regions of the circular SM oesophagus by Western blots. Patch clamp technique was utilized to study L(Ca) currents. Muscle strip studies assessed L(Ca) contribution to contractile activity. The protein expression of L(Ca) and L(Ca) current density was greater in the proximal than distal region. L(Ca) voltage and time-dependent activation and inactivation curves were similar in cells from both regions. Stimulation of muscle strips with acetylcholine (ACh) in the presence of tetrodotoxin resulted in contractions of greater amplitude in the proximal region. The L(Ca) agonist Bay K 8644 caused a greater increase in ACh-induced contraction amplitude in muscle strips from the proximal region. Therefore, regional myogenic differences in L(Ca) expression along the circular SM oesophageal body exist and may contribute to the nature of oesophageal contractions.

Regional differences in the response of feline esophageal smooth muscle to stretch and cholinergic stimulation.

There are no objective differences in neural elements that explain regional differences in neural influences along the smooth muscle (SM) esophageal body (EB). Regional differences in muscle properties are present in the lower esophageal sphincter (LES). This study examines whether regional differences in SM properties exist along the EB and are reflected in length-tension relationships and responses to cholinergic excitation. Circular SM strips from feline EB at 1 cm (EB1) and 3 cm (EB3) above LES and from clasp and sling muscle bundles of LES were assessed in normal and calcium-free solutions with and without bethanechol stimulation. Neural inhibition was assessed by electrical field stimulation (EFS). EB3 developed significantly higher tension in response to stretch and to bethanechol than did EB1. The relaxation response to EFS in bethanechol-precontracted strips was less in EB3 than in EB1. In LES, clasp developed higher resting tension than sling but less active tension in response to bethanechol. EFS-induced relaxations of sling and clasp tissues precontracted by bethanechol were not different. In calcium-free solution, length-tension differences between EB3 and EB1 persisted, but those of LES clasp and sling were abolished. Therefore, regional myogenic differences exist in feline EB circular SM as well as in LES and may contribute to the nature of esophageal contraction.

Initiation of distension-induced descending peristaltic reflex in opossum esophagus: role of muscle contractility.

The balloon distension (BD)-induced descending peristaltic reflex in the opossum smooth muscle esophagus is abolished in vitro when a Ca(2+)-free Krebs solution is placed at the site of distension, suggesting that either synaptic transmission occurs at the origin of the reflex or initiation of the reflex requires the development of muscle tension in response to BD. To test the latter possibility, an 8- to 10-cm length of smooth muscle esophagus was placed in a dual-chamber organ bath, isolating the stimulating (orad) from the recording site (aborad). Nifedipine addition to the orad chamber (i.e., site of distension) inhibited the BD-induced "off" contractions in both chambers in a concentration-dependent manner. However, the aborad response to electrical field stimulation (EFS) was unaffected. Atropine addition to the orad chamber had no effect on BD or EFS responses in either chamber. To examine the effects of these agents on tonic contractility, an isobaric barostat was employed. Pressure-volume curves were not altered by Ca(2+)-free Krebs solution, nifedipine, or TTX, suggesting that resting esophageal tone is not dependent on neural factors or muscle contractility. However, both Ca(2+)-free Krebs solution and nifedipine markedly decreased phasic contractions over the top of the distending bag. These observations suggest that local, stretch-induced phasic muscle contraction is required for initiation of the BD-induced descending peristaltic reflex.