Smad2/3 Linker Phosphorylation Is a Possible Marker of Pancreatic Stem/Progenitor Cells in the Regenerative Phase of Acute Pancreatitis.

OBJECTIVES: The aims of this study are to characterize cell proliferation and differentiation during regeneration after pancreatitis and pancreatic buds during development to evaluate the role of Smad2/3, phosphorylated at the specific linker threonine residues (pSmad2/3L-Thr) in positive cells. METHODS: Male C57BL/6 mice received hourly intraperitoneal injections of cerulein and were analyzed after induced pancreatitis. Pancreatitis-affected tissue sections and pancreatic buds were immunostained for pSmad2/3L-Thr, with other markers thought to be stem/progenitor markers of the pancreas. RESULTS: pSmad2/3L-Thr immunostaining-positive cells increased as the pancreatitis progressed. The expression of pSmad2/3L-Thr was seen in acinar cells and ductlike tubular complexes. These results suggest that pSmad2/3L-Thr is expressed during acinar-ductal metaplasia. Immunohistochemical colocalization of pSmad2/3L-Thr with Ki67 was never observed. pSmad2/3L-Thr-positive cells may remain in an undifferentiated state. During the pancreatic development process, pSmad2/3L-Thr was expressed as other markers. pSmad2/3L-Thr develops in duct structure of the undifferentiated cell population in the last part of viviparity that acinar structure is formed clearly. CONCLUSIONS: pSmad2/3L-Thr expression occurs during acinar-ductal metaplasia after pancreatitis and may represent the contribution of stem cells and/or progenitor cells to the differentiation of the pancreas.

Utility of newly developed short-type double-balloon endoscopy for endoscopic retrograde cholangiography in postoperative patients.

BACKGROUND AND AIM: The utility of conventional short-type double-balloon endoscopy (DBE) for pancreatobiliary disease in patients with postoperative anatomy had been widely acknowledged and accepted. However, some technical difficulties yet remained. In an attempt to solve these problems, the new short-type DBE (N-short DBE) was uniquely designed for therapeutic endoscopic retrograde cholangiography (ERC) in postoperative patients. The aim of this study was to evaluate the usefulness of N-short DBE for ERC in postoperative patients. METHODS: From August 2015 to April 2016, ERC using N-short DBE (DB-ERC) was performed in 100 postoperative patients (112 procedures). We retrospectively studied the success rate of reaching the blind end, the median time to reach the blind end, the diagnostic success rate, the therapeutic success rate, the median time to complete ERC-related interventions, the overall success rate, the median time to complete DB-ERC, and adverse events. RESULTS: The success rate of reaching the blind end was 99.1%. The median time to reach the blind end was 10 min (interquartile range [IQR], 6-19 min). The diagnostic success rate was 98.2%. The therapeutic success rate was 100%. The median time to complete ERC-related interventions was 36 min (IQR, 22-62 min). The overall DB-ERC success rate was 97.3%. The median time to complete DB-ERC was 54 min (IQR, 37-73 min). The occurrence of adverse events was 2.7%. CONCLUSIONS: The N-short DBE for ERC in postoperative patients is useful and safe. DB-ERC is promising therapeutic modality in such patients and should be selected as the first-line policy.

Phosphorylation of Smad2/3 at specific linker threonine indicates slow-cycling intestinal stem-like cells before reentry to cell cycle.

BACKGROUND: Quiescent (slow-cycling) and active (rapid-cycling) stem cells are demonstrated in small intestines. We have identified significant expression of Smad2/3, phosphorylated at specific linker threonine residues (pSmad2/3L-Thr), in murine stomach, and suggested these cells are epithelial stem cells. AIM: Here, we explore whether pSmad2/3L-Thr could serve as a biomarker for small intestine and colon stem cells. METHODS: We examined small intestines and colons from C57BL/6 mice and colons with dextran sulfate sodium (DSS)-induced colitis. We performed double-immunofluorescent staining of pSmad2/3L-Thr with Ki67, cytokeratin 8, chromogranin A, CDK4, DCAMKL1, and Musashi-1. Small intestines and colons from Lgr5-EGFP knock-in mice were examined by pSmad2/3L-Thr immunofluorescent staining. To examine BrdU label retention of pSmad2/3L-Thr immunostaining-positive cells, we collected specimens after BrdU administration and observed double-immunofluorescent staining of pSmad2/3L-Thr with BrdU. RESULTS: In small intestines and colons, pSmad2/3L-Thr immunostaining-strongly positive cells were detected around crypt bases. Immunohistochemical co-localization of pSmad2/3L-Thr with Ki67 was not observed. pSmad2/3L-Thr immunostaining-strongly positive cells showed co-localization with cytokeratin 8, CDK4, and Musashi-1 and different localization from chromogranin A and DCAMKL1 immunostaining-positive cells. Under a light microscope, pSmad2/3L-Thr immunostaining-strongly positive cells were morphologically undifferentiated. In Lgr5-EGFP knock-in mice, some but not all pSmad2/3L-Thr immunostaining-strongly positive cells showed co-localization with Lgr5. pSmad2/3L-Thr immunostaining-strongly positive cells showed co-localization with BrdU at 5, 10, and 15 days after administration. In DSS-induced colitis, pSmad2/3L-Thr and Ki67 immunostaining-positive cells increased in the regeneration phase and decreased in the injury phase. CONCLUSION: In murine small intestines and colons, we suggest pSmad2/3L-Thr immunostaining-strongly positive cells are epithelial stem-like cells just before reentry to the cell cycle.

Combined treatment of large hepatocellular carcinoma with transcatheter arterial chemoembolization and percutaneous ethanol injection with a multipronged needle: experimental and clinical investigation.

PURPOSE: This study was designed to evaluate the usefulness of percutaneous ethanol injection (PEI) with a multipronged needle for the treatment of large hepatocellular carcinoma (HCC). An experimental animal study and a clinical investigation were performed. METHODS: In the experimental study, 20 ml of 99.5% ethanol was injected into porcine liver in vivo with a multipronged needle (n = 5) or a straight needle (n = 5), and the volumes of coagulation necrosis were compared. In the clinical investigation, PEI was performed in 17 patients (10 men, 7 women; mean age 73.4 ± 6.7 years) with single, large HCC (mean tumor diameter, 47.2 ± 11.5 mm; range, 32-70 mm) by using a multipronged needle. Fifteen of 17 patients received transarterial chemoembolization (TACE) before PEI. RESULTS: The volume of coagulation in porcine liver in vivo was significantly increased with the multipronged needle compared with the straight needle (longest perpendicular diameters, 34.2 ± 3.6 mm × 30.2 ± 3.6 mm vs. 22.6 ± 2.5 mm × 19 ± 2.2 mm, respectively; P < 0.05). In the clinical trial, initial complete response (CR) of the tumor was achieved in 17 of 17 patients, 7 of whom required two PEI sessions. During the follow-up, local recurrence was detected in 4 of 17 patients at 3-19 months after the procedure, for a rate of sustained local CR of 76%. No major complication occurred. CONCLUSIONS: Use of a multipronged needle substantially increases the volume of coagulation in vivo with respect to the conventional PEI technique. Combined TACE and PEI with multipronged needles is a safe and effective option for percutaneous treatment of single, large HCC.