Tyrosine phosphorylation of Kv1. 5 is upregulated in intrauterine growth retardation rats with exaggerated pulmonary hypertension

Intrauterine growth retardation (IUGR) is associated with the development of adult-onset diseases, including pulmonary hypertension. However, the underlying mechanism of the early nutritional insult that results in pulmonary vascular dysfunction later in life is not fully understood. Here, we investigated the role of tyrosine phosphorylation of voltage-gated potassium channel 1.5 (Kv1.5) in this prenatal event that results in exaggerated adult vascular dysfunction. A rat model of chronic hypoxia (2 weeks of hypoxia at 12 weeks old) following IUGR was used to investigate the physiological and structural effect of intrauterine malnutrition on the pulmonary artery by evaluating pulmonary artery systolic pressure and vascular diameter in male rats. Kv1.5 expression and tyrosine phosphorylation in pulmonary artery smooth muscle cells (PASMCs) were determined. We found that IUGR increased mean pulmonary artery pressure and resulted in thicker pulmonary artery smooth muscle layer in 14-week-old rats after 2 weeks of hypoxia, while no difference was observed in normoxia groups. In the PASMCs of IUGR-hypoxia rats, Kv1.5 mRNA and protein expression decreased while that of tyrosine-phosphorylated Kv1.5 significantly increased. These results demonstrate that IUGR leads to exaggerated chronic hypoxia pulmonary arterial hypertension (CH-PAH) in association with decreased Kv1.5 expression in PASMCs. This phenomenon may be mediated by increased tyrosine phosphorylation of Kv1.5 in PASMCs and it provides new insight into the prevention and treatment of IUGR-related CH-PAH.

Submucosal tunneling endoscopic resection for upper gastrointestinal multiple submucosal tumors originating from the muscular propria layer: A feasibility study.

BACKGROUND AND AIMS: In recent years, submucosal tunneling endoscopic resection (STER) was applied more and more often for single gastrointestinal (GI) submucosal tumor (SMT). However, little is known about this technique for treating multiple SMTs in GI tract. In the present study, we investigated the feasibility and outcome of STER for upper GI multiple SMTs originating from the muscularis propria (MP) layer. PATIENTS AND METHODS: A feasibility study was carried out including a consecutive cohort of 23 patients with multiple SMTs from MP layer in esophagus, cardia, and upper corpus who were treated by STER from June 2011 to June 2014. Clinicopathological, demographic, and endoscopic data were collected and analyzed. RESULTS: All of the 49 SMTs were resected completely by STER technique. Furthermore, only one tunnel was built for multiple SMTs of each patient in this study. En bloc resection was achieved in all 49 tumors. The median size of all the resected tumors was 1.5 cm (range 0.8–3.5 cm). The pathological results showed that all the tumors were leiomyoma, and the margins of the resected specimens were negative. The median procedure time was 40 min (range: 20–75 min). Gas‑related complications were of the main complications, the rates of subcutaneous emphysema and pneumomediastinum, pneumothorax, and pneumoperitoneum were 13.0%, 8.7% and 4.3%. Another common complication was thoracic effusion that occurred in 2 cases (8.7%), among which only 1 case (4.3%) with low‑grade fever got the drainage. Delayed bleeding, esophageal fistula or hematocele, and infection in tunnel were not detected after the operation there were no treatment‑related deaths. The median hospital stay was 4 days (range, 2–9 days). No residual or recurrent lesion was found during the follow‑up period (median 18, ranging 3–36 months). CONCLUSION: Submucosal tunneling endoscopic resection is a safe and efficient technique for treating multiple esophageal SMTs originating from MP layer, which can avoid patients suffering repeated resections.

Is endoscopic sphincterotomy plus large-balloon dilation a better option than endoscopic large-balloon dilation alone in removal of large bile duct stones? A retrospective comparison study.

Background: Several comparison studies have demonstrated that endoscopic sphincterotomy (EST) combined with large-balloon dilation (LBD) may be a better option than EST alone to manage large bile duct stones. However, limited data were available to compare this combination method with LBD alone in removal of large bile duct stones. Objective: To compare EST plus LBD and LBD alone for the management of large bile duct stones, and analyze the outcomes of each method. Patients and Methods: Sixty-one patients were included in the EST plus LBD group, and 48 patients were included in the LBD alone group retrospectively. The therapeutic success, clinical characteristics, procedure-related parameters and adverse events were compared. Results: Compared with EST plus LBD, LBD alone was more frequently performed in patients with potential bleeding diathesis or anatomical changes (P = 0.021). The procedure time from successful cannulating to complete stone removal was shorter in the LBD alone group significantly (21.5 vs. 17.3 min, P = 0.041). The EST plus LBD group and the LBD alone group had similar outcomes in terms of overall complete stone removal (90.2% vs. 91.7%, P = 1.000) and complete stone removal without the need for mechanical lithotripsy (78.7% vs. 83.3%, P = 0.542). Massive bleeding occurred in one patient of the EST plus LBD group, and successfully coagulated. Postoperative pancreatitis did not differ significantly between the EST plus LBD group and the LBD alone group (4.9% vs. 6.3%; P = 1.000). Conclusion: Endoscopic sphincterotomy combined with LBD offers no significant advantage over LBD alone for the removal of large bile duct stones. LBD can simplify the procedure compared with EST plus LBD in terms of shorten the procedure time.