Akihide Tanano

Duodenogastric reflux following biliary reconstruction after excision of choledochal cyst

Duodenogastric reflux (DGR) was assessed in patients surgically treated for choledochal cyst, with emphasis on two different biliary reconstruction methods: Roux-en-Y hepaticojejunostomy (HJ) and hepaticoduodenostomy (HD). Gastric bile monitoring with the Bilitec device revealed excessive DGR in patients in the HD group. Endoscopic findings demonstrated mild to moderate gastric mucosal erosion in patients after HD. In contrast, neither DGR nor gastritis was found in patients after HJ. This preliminary study suggests that HJ, rather than HD, should be recommended as a method of biliary reconstruction for pediatric patients with choledochal cyst. Careful observation of DGR should be continued in patients who have undergone HD.

Magnetic resonance cholangiopancreatography on postoperative work-up in children with choledochal cysts

This study aimed to assess the clinical usefulness of magnetic resonance cholangiopancreatography (MRCP) as a postoperative diagnostic tool in children with choledochal cysts. Magnetic resonance cholangiopancreatography was performed postoperatively in 19 patients and image quality was compared with that obtained by intravenous cholangiography spiral computed tomography (IVC-SCT). While the detectability by MRCP was inferior to that by IVC-SCT, MRCP highly (84.2%) depicted the anastomotic site together with the reconstructed bowel and intrahepatic bile ducts. Magnetic resonance cholangiopancreatography also clearly delineated the postoperative condition of pancreaticobiliary maljunction (PBM), residual distal common bile duct, common channel, and pancreatic duct. Since MRCP is noninvasive and requires neither radiation exposure nor a contrast agent, and is useful for detecting both anastomosis and pancreatico-biliary ducts around PBM, MRCP might be superior to IVC-SCT as an imaging technique for outpatient clinics performing long-term follow-up studies in children with choledochal cysts.

Intrapancreatic axonal hyperbranching of dorsal root ganglia neurons in chronic pancreatitis model rats and its relation to pancreatic pain.

Objectives: Increase in number of intrapancreatic nerve bundles has been implicated in the generation of persistent pain in chronic pancreatitis. To examine the origin of these nerve fibers and the mechanisms linking neural morphological change to pain generation, we used neuronal tracing techniques in combination with immunohistochemistry in spontaneous chronic pancreatitis in the Wistar Bonn/Kobori (WBN/Kob) rats. Methods: For retrograde tracing, horseradish peroxidase was injected into the pancreas, and labeled neurons in the sensory ganglia were counted. For anterograde tracing, biotinylated dextran amine was injected into the dorsal root ganglia (DRGs), and labeled intrapancreatic sensory fibers were histochemically assessed. For assessment of pain generation, we evaluated c-Fos-positive neurons in the spinal dorsal horn and behavioral changes of the animals. Results: In WBN/Kob rats, the numbers of horseradish peroxidase-labeled neurons were decreased in the DRGs, and the numbers of biotinylated dextran amine-labeled intrapancreatic nerve fibers and terminals were increased. Biotinylated dextran amine-labeled nerve fibers contained growth-associated protein 43. The number of c-Fos-positive neurons in the dorsal horn was also increased and was correlated with intrapancreatic growth-associated protein 43 immunoreactivity. Grooming behavior was reduced in WBN/Kob rats, and this reduction was facilitated by exocrine stimulation. Conclusions: Axonal branching in DRG neurons innervating the pancreas increases in WBN/Kob rats, and these morphological changes are likely involved in pain generation in chronic pancreatitis.

Ovarian Teratoma with Gliomatosis Peritonei : Report of Two Cases

Gliomatosis peritonei, a rare condition related to ovarian teratomas, involves the peritoneal implantation of numerous nodules of predominantly mature glial tissues. We report herein the cases of two patients with immature ovarian teratoma associated with gliomatosis peritonei, in one of whom a rapid progression of teratomatous implants occurred 14 weeks after her initial surgery. Gliomatosis peritonei is considered benign in most cases; however, some reports have documented the rapid recurrence of immature peritoneal implants, as implantation is associated with teratomas of all grades. Thus, in the face of peritoneal implants suspected to be of a teratomatous nature, thorough and extensive sampling is essential to exclude the presence of immature elements which may imply a poor prognosis and require aggressive therapy.

Effect of perductal paclitaxel exposure on the development of MNU-induced mammary carcinoma in female S-D rats.

SummaryBackground. Breast carcinoma and precancer are thought to start in the lining of the milk duct or lobule. Methods. At 5weeks of age, rats received a intraperitoneal (ip) injection of MNU for carcinogenesis. After mammary tumors were identified macroscopically using fiberscope, the rats were treated with perductal (pd) or ip injection of paclitaxel tri-weekly. At 36 weeks after MNU injection, tumor burden (No. of >1cm palpable mammary tumors/rat), total number of mammary carcinoma, apoptosis (AI), and microvessel density (MVD) were measured. Results. The administration of paclitaxel through the duct did not produce any toxic side effect. The tumor burden and total number of mammary carcinoma in the pd paclitaxel-treated group were significantly reduced compared to those seen in the ip paclitaxel-treated group. In addition, in the pd paclitaxel-treated group, AI was also increased and MVD was decreased, compared to those in the ip paclitaxel-treated group. Conclusion. Local administration of paclitaxel may be useful for treatment of breast cancer.

Congenital biliary dilatation in dizygotic twins.

Congenital biliary dilatation (CBD) of different types was recently noted in dizygotic twins. Our cases suggest the possibility of hereditary involvement in CBD. On the other hand, CBD discordance in six sets of monozygotic twins has been reported, which would suggest that the occurrence of CBD is not compatible with single gene control, although environmental factors are plausible. To evaluate the genetic factors that may be implicated in CBD, it would be necessary to accumulate more familial cases and examine further studies on inheritance.

Structural development of PGP9.5-immunopositive myenteric plexus in embryonic rats

To investigate relationships between changes in the 3-dimensional structure of the myenteric plexus and the time at which functional movement of intestine begins in mammalian embryos, whole mounts of embryonic rat intestine were examined under confocal laser scanning microscopy on spacer-equipped glass slides after immunostaining with antiprotein gene product 9.5 antibody. At embryonic day 12.5, very few nerve cells were scattered throughout the small intestine, but no immunostained structures were apparent on the anal side of the large intestine. At embryonic day 13.5, immunostained fibers appeared on the oral side of the large intestine. Nerve cells and associated fiber bundles formed neuronal networks with large meshes in both intestines. Marked increases in number of nerve fibers and decreases in mesh size were seen in the small intestine between embryonic days 13.5 and 15.5. Similar changes were found in the large intestine between embryonic days 13.5 and 16.5. After embryonic day 16.5, nerve cells were arranged parallel to circular muscle fibers, and networks formed by cell fibers elongated until the neonatal period in both intestines. Meconium passed through the large intestine from embryonic day 17.5. Thin fiber bundles extended from the ganglion to the inner side of the myenteric layer, parallel (and occasionally extending) to the circular muscle fibers. Formation of nerve fiber networks and arrangement of nerve cells parallel to circular muscle fibers probably relate to movement coordination for inner circular muscle fibers in the intestinal wall, and development of this neural network may be important for acquiring intestinal movements before birth.

Anorectal Stenosis in a Neonate: Report of a Case and Review of the Japanese Literature

We report herein the case of an infant with anorectal stenosis successfully treated by staged surgery. At 1 day of age, the anal orifice showed circumferential stenosis located 5 mm from the anal verge and extending into the anal canal for approximately 1 cm; however, no hypertrophic raphe or bucket handle appearance were observed, and no associated anomalies such as a presacral mass or sacral dysgenesis were found. At 2 days of age, the infant underwent a sigmoid colostomy under the diagnosis of low anorectal stenosis, followed by a successful anorectoplasty, performed through a sacroperineal approach when he was 8 months old. An analysis of 13 other cases of anorectal stenosis from the Japanese literature indicates that this type of malformation should be treated by staged surgery, as an initial colostomy in the neonatal period, followed by anorectoplasty through a sacroperineal approach during infancy.