Disappearance of centroacinar cells in the Notch ligand-deficient pancreas.

Notch signaling has been shown to contribute to murine pancreatic development at various stages. Delta-like 1 (Dll1) or Jagged1 (Jag1) are the Notch ligands that solely function to trigger this signaling during the pancreatic bud stage (~e9.5) or after birth, respectively. However, it has not been elucidated whether these Notch ligands are required at the later stage (e10.5-18.5) when the particular pancreas structures form. Here, we detected the dual expression of Dll1 and Jag1 in the epithelium after e10.5, which was restricted to the ductal cell lineage, including centroacinar cells expressing Sox9, CD133 and Hes1 but not the ductal cell markers Hnf1ß and DBA, at e18.5. To evaluate the significance of the Notch ligands during this period, we established double-floxed mice of Dll1 and Jag1 genes with Ptf1a-Cre knock-in allele and examined the effects on development. The abrogation of both ligands but not a single one led to the loss of centroacinar cells, which was due to the decrease in cell proliferation and the increase in cell death, as well as to the reduction of Sox9. These results suggested that Dll1 and Jag1 function redundantly and are necessary to maintain the centroacinar cells as an environmental niche in the developing pancreas.

A case of small bowel ulcer caused by NSAIDs and detected after capsule endoscope retention.

We recently detected an annular ulcer thought to have been caused by non-steroidal anti-inflammatory drugs (NSAIDs) when we performed small bowel capsule endoscopy on a patient with suspected small-bowel bleeding and a history of frequent use of oral NSAIDs. The patient was a 64-year-old woman who complained of bloody stools and abdominal pain. The annular ulcer showed concentric stenosis, which caused retention of the capsule endoscope. NSAIDs are some of the most frequently used anti-inflammatory analgesics, and even more frequent use can be expected with the aging of society. No reports to date appear to have described retention of a capsule endoscope due to annular ulceration caused by NSAIDs. We report herein our experience with a patient showing small-bowel ulcer caused by NSAIDs.

Ultrasonographic diagnosis of adult intussusception caused by pedunculated colon carcinoma.

Adult intussusception is clinically rare. We report a case with colon intussusception caused by a pedunculated polyp of the sigmoid colon in a 54-year-old male. Abdominal ultrasonographic screening for hematochezia showed intussusception in the sigmoid colon, demonstrating a multiple concentric ring sign and a mobile leading colon polyp. Histological examination of a biopsy specimen of the polyp revealed adenoma. This report suggests that ultrasound imaging is a modality of choice for differential diagnosis of intestinal intussusception with hematochezia in adults.

Clinical utility of double-balloon enteroscopy for small intestinal bleeding.

Until the development of wireless capsule endoscopy (CE) and double-balloon enteroscopy (DBE), it was extremely difficult to examine the entire small intestine. To assess the usefulness of DBE for diagnosing suspected small intestinal bleeding, we retrospectively compared the diagnoses and treatments of cases before and after its introduction at one hospital. Between September 2003 and December 2005, 21 consecutive patients with suspected small intestinal bleeding underwent DBE at Tokai University Hospital (group A), and subsequently 2 were excluded from the study after being diagnosed with bleeding from a diverticulum and an angiodysplasia in the ascending colon, respectively. For comparison, inpatients who were negative for gastrointestinal bleeding on colonoscopy and gastroscopy between May 1998 and August 2003 were reviewed and 27 consecutive patients who had not undergone DBE were selected as the control group (group B). All patients had been diagnosed negative for a source of bleeding on more than one colonoscopy and gastroscopy. There were no significant differences between the two groups in terms of age, gender, history of blood transfusion, blood hemoglobin value on admission, or symptoms. The diagnostic yield of DBE in identifying the source of bleeding was 78.9%: six cases of small intestinal ulcers, five cases of angiodysplasia, two cases of hard submucosal tumor (SMT), one case of small pulsating SMT, and one case of small intestinal cancer. DBE was also used to successfully treat three cases of angiodysplasia with argon plasma coagulation. In the control group, conventional investigations, including enteroclysis, angiography, Meckel scan, scintigraphy with technetium-labeled red blood cells, and/or push enteroscopy, were performed in 88.9%, 29.6%, 29.6%, 55.6%, and 25.9%, respectively. The overall diagnostic yield of the conventional approaches was only 11.1% (P < 0.01), comprising a Meckel's diverticulum, a polyp, and an angiodysplasia. We conclude that DBE can be used to diagnose suspected small intestinal bleeding and to treat some cases, such as angiodysplasia.