Balanced organogenesis requires the orchestration of multiple cellular interactions to create the collective cell behaviours that progressively shape developing tissues. It is currently unclear how individual, localized parts are able to coordinate with each other to develop a whole organ shape. Here we report the dynamic, autonomous formation of the optic cup (retinal primordium) structure from a three-dimensional culture of mouse embryonic stem cell aggregates. Embryonic-stem-cell-derived retinal epithelium spontaneously formed hemispherical epithelial vesicles that became patterned along their proximal-distal axis. Whereas the proximal portion differentiated into mechanically rigid pigment epithelium, the flexible distal portion progressively folded inward to form a shape reminiscent of the embryonic optic cup, exhibited interkinetic nuclear migration and generated stratified neural retinal tissue, as seen in vivo. We demonstrate that optic-cup morphogenesis in this simple cell culture depends on an intrinsic self-organizing program involving stepwise and domain-specific regulation of local epithelial properties.
Introduction Pancreaticobiliary maljunction (PBM) is a congenital anomaly, which can be defined as a union of the pancreatic and biliary ducts located outside off the duodenal wall. We herein investigate clinical features of PBM including as the 2nd report of a Japanese nationwide survey.Patients and methods During a period of 18 years (from 1990 to 2007), 2,561 patients with PBM were registered at 141 medical institutions in Japan. Among them, eligible patients (n = 2,529) were divided into two groups: adult (n = 1,511) and pediatric patients (n = 1,018). Comparisons of clinical features including associated biliary cancers were performed according to the biliary dilatation (BD), age factor, and time era. Results Only one case in pediatric patients with BD combined with a bile duct cancer (0.1 %). In adult patients, the bile duct cancer and the gallbladder cancer was seen in 6.9 and 13.4 % patients with BD and in 3.1 and 37.4 % patients without BD, respectively. In adult patients with BD, the occurrence rates of biliary cancers were increased in latter period (00'-07') compared with former period (90'-99'). The ratio of biliary cancer localization was changed between former and latter period, and the bile duct cancer was increased in latter period (from 5.5 to 9.3 %).Conclusions The largest series of PBM were evaluated to clarify the clinical features including the associated biliary cancer in this Japan-nationwide survey. This report could be widely used in the future as a reference data for diagnosis and treatment of PBM.
Until now, there have been no practical clinical guidelines for congenital biliary dilatation (CBD). In this review article, the Japanese Study Group on Congenital Biliary Dilatation (JSCBD) propose to establish clinical practice guidelines for CBD. Because the evidence-based literature is relatively small, we decided to create guidelines based on the consensus of experts, using the medical literature for reference. A total of 20 clinical questions (CQs) were considered by the members of the editorial committee responsible for the guidelines. The CQs included the distinct aspects of CBD: (1) Concepts and Pathology (three CQs); (2) Diagnosis (six CQs); (3) Pancreaticobiliary Complications (three CQs); Treatments and Prognosis (eight CQs). Each statements and comments for CQs were made by the guidelines committee members. CQs were finally approved after review by members of the editorial committee and the guidelines evaluation board of CBD. These guidelines were created to provide assistance in the clinical practice of CBD management; their contents focus on clinical utility, and they include general information on CBD to make this disease more widely recognized.
Heterotopic pancreas (HP) is rarely recognized during surgery. Many reports concerning this anomaly are simple case reports. We herein review our experiences with HP. We retrospectively investigated cases of HP from April 1975 to September 2006. We discussed the frequencies in the laparotomized patients, and patient's age, gender, operative indication, location of HP, post-operative diagnosis and pathology. A total of 12 patients with HP, 3 boys and 9 girls, aged 1 day to 10 years of age were investigated. Ten patients had one pattern of HP and the remaining two had more than one. The locations of the HP were as follows: Meckel's diverticulum, 4; stomach, 3; duodenum, 3; jejunum, 3; and ileum, 2. Only in one patient HP had caused an intussusception. The remaining 11 cases were identified incidentally during the operation. In 11 of 12 patients, HP was removed without post-operative complications. Classification of pathologies according to Heinrich is as follows: type I, 4; type II, 4; type III, 2 and unknown, 2. Patients with HP are usually asymptomatic. However, HP caused an intussusception in our series. Incidental HPs should be removed whenever identified during laparotomy.
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