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Paramagnetic beads have the superior advantages of easy separation and resuspension by controlling the magnetic filed. Previously, we have developed Magtration technology to automate paramagnetic bead handling and have built several automated instruments that handle 1–12 samples simultaneously. To achieve more high-throughput sample processing, two types of a 96-arrayed Integrated Magtration Unit (IMU) were developed, one installed with electromagnets and the other with thin rod-shaped magnets made of neodymium. A multipurpose robot (SX-96GC) equipped with the IMU was also developed for fully automatic processing of 96 samples in parallel. The cleanup of dye-terminator sequencing products was performed using the robot installed with the permanent magnet version of IMU. The results had quality comparable to those by the same protocol in manual handling or to those by the conventional protocols. The robot processed 96 samples in a microplate within 30 min. The protocol that can purify 384 samples within 1 h by processing two microplates concurrently was successfully designed.

Purpose: The authors used ultrasonographic endoprobes during laparoscopy-assisted colon pull-through (LACPT) for the repair of high imperforate anus to confirm the pull-through canal was surrounded symmetrically by pelvic floor muscles. Methods: Six patients with high imperforate anus were treated by LACPT (mean age at LACPT, 8.2 months). An endoscopic (12-MHz, 2.5-mm in diameter) and proctoscopic (7.5-MHz, 12-mm in diameter) probe were inserted into the proposed route of dissection intraoperatively to measure the thickness of the surrounding muscle tissue at at least 3 levels: the external anal sphincter, the levator ani muscle sling, and the intervening muscle complex. Results: The average thickness of the external anal sphincter was 2.3 ± 0.4 mm anteriorly, 2.4 ± 0.4 mm on the left, 2.4 ± 0.5 mm posteriorly, and 2.6 ± 0.6 mm on the right. The average thickness of the muscle complex was 2.3 ± 0.6 mm anteriorly, 2.2 ± 0.5 mm on the left, 2.1 ± 0.4 mm posteriorly, and 2.2 ± 0.5 mm on the right. The average thickness of the left crus of the levator ani muscle was 1.8 ± 0.3 mm, the right crus was 1.9 ± 0.4 mm, and the rim located posterior to the rectum was 2.0 ± 0.3 mm. No statistically significant difference was found between the measurements taken at each level. Conclusion: Intraoperative endosonography during LACPT can greatly enhance the precision of positioning the pull-through canal. J Pediatr Surg 37:1657-1660. Copyright 2002, Elsevier Science (USA). All rights Reserved.

Background: It is crucial to identify the exact level of transition to normal ganglion cells in instances of Hirschprung's disease. This report describes a technique for laparoscopy-assisted suction colonic biopsy during transanal pull-through. Methods: Laparoscopy-assisted suction colonic biopsy (SCBx) was used in 12 patients with Hirschsprung's disease affecting the rectosigmoid. Average age was 4.4 ± 2.1 months with a mean operative weight 6.2 ± 1.0 kg. The pull-through was performed as the primary operative procedure in 11 patients. Using a 2-team approach (laparoscopic team and transanal team), the site was chosen for transanal suction biopsy and marked externally by the laparoscopic team with a silver clip. Biopsies were processed for ganglion cells and rapid AChE technique. Results: There were no biopsy-induced perforations. Abnormal biopsies were repeated more proximally until ganglion cells were observed. Transanal pull-through was performed and an open full-thickness biopsy performed to confirm the presence of ganglion cells. All procedures were performed successfully. Conclusions: Laparoscopy-assisted SCBx can be used successfully in patients with Hirschsprung's disease affecting the rectosigmoid (80% of cases). The technique, when used with rapid AChE staining, provides accurate identification of the level of normoganglionosis. J Pediatr Surg 37:1661-1663. Copyright 2002, Elsevier Science (USA). All rights reserved.

A new continuous speech recognition method that does not need explicit speech end-point detection is proposed. A one-pass decoding algorithm is modified to decode the input speech of infinite length so that, with appropriate nonspeech models for silence and ambient noises, continuous speech recognition can be executed without explicit end-point detection. The basic algorithm (1) decodes a processing block of the predetermined length, (2) backtraces and finds the boundaries of the processing blocks where the word history in the preceding processing block is merged into one, and (3) restarts decoding from the boundary frame with the merged word history. The effectiveness of the method is verified by spoken dialogue transcription experiments. With a 5-minute dialogue in a moving car, the proposed method gives better results in word accuracy than the results using the explicit end-point detection method and the conventional one-pass decoder. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(4): 43–50, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20140

Purpose: Our technique for laparoscopic muscle electrostimulation during laparoscopy-assisted anorectal pull-through (LAARPT) for high imperforate anus (HIA) in 3 patients is described. Methods: The distal rectum and rectourethral fistula is dissected laparoscopically. A muscle stimulator is passed through one of the trocars and used to identify the center of contraction of the levator ani. The same muscle stimulator is used to identify the center of the external sphincter muscle transcutaneously. An intravenous cannulation device (SURFLO Flash IV catheter, TERUMO, CO, Yamanashi, Japan) is inserted through this proposed anus and observed piercing the center of the levator ani. A guide wire is passed through the SURFLO, and a series of dilators are passed along it to create a canal for the colonic pull-through. An anoplasty then was performed. Results: Our technique was successful in all patients. Laparoscopic electrostimulation produced good levator ani contraction in patients I and II and weak contraction in patient III. Patients I and II have symmetrical anal contraction during rectal examination, but patient III has poor contraction. Stool frequency is decreasing in all. Conclusion: Direct laparoscopic observation of levator ani contraction allows intraoperative assessment of functional contractility and assists in the accurate placement of the colonic pull-through. J Pediatr Surg 36:1659-1661. Copyright © 2001 by W.B. Saunders Company.

Magnetic resonance cholangiopancreatography (MRCP) is a new noninvasive method of obtaining images of the pancreaticobiliary tract. Recent advances in MR technology and image quality have made it easy to diagnose structural abnormalities of the pancreaticobiliary tract (SAPBT) in children. To examine the usefulness of MRCP in assessing the cause of acute pancreatitis in children, we performed MRCP in 16 patients with acute pancreatitis. The study population was divided into two groups according to the cause of acute pancreatitis as follows: group 1 consisted of seven patients sonographically diagnosed with choledochal cysts; and group 2 consisted of nine patients with no obvious cause of acute pancreatitis. Non-breath-hold MRCP using the half-Fourier, single-shot, fast spin-echo imaging method was performed within 7 days after the onset of pancreatitis. Abnormal union of the pancreaticobiliary junction was detected in six of seven group 1 patients and in one of nine group 2 patients. Pancreatic divisum was detected in one patient of group 1, but could not be confirmed in one patient of group 2. Dilatation of the main pancreatic duct was detected in one patient of group 1 and in three patients of group 2. Our results suggest that MRCP is a useful, noninvasive method of identifying and ruling out SAPBT as a cause of acute pancreatitis in children with early-stage pancreatitis.

Purpose: The aim of this study was to show that a tubed latissimus dorsi musculocutaneous flap (tubed LDMCF) may be useful for treating circumferential esophageal defects. Methods: A segment of esophagus 3 vertebrae long was excised through a right thoracotomy in each of 6 puppies, and a tubed LDMCF was interposed between the cut ends of esophagus. The puppies were sacrificed after a mean follow-up period of 6.6 years. The tubed LDMCF was examined histologically. Functional integrity was assessed using barium meal and endoscopy before sacrifice. Results: All puppies survived and grew normally on a normal diet, although 4 vomited occasionally. There was smooth passage of barium through the tubed LDMCF without stenosis, although endoscopy showed regrowth of hair. Histologically, no metaplasia, dysplasia, or malignancy was observed in any tubed LDMCF. Conclusions: The tubed LDMCF is technically safe, obviates the necessity for laparotomy, and long-term follow-up would suggest that it is histologically stable. Thus, it could become an alternative procedure for bridging esophageal defects. J Pediatr Surg 35:1623-1625. Copyright © 2000 by W.B. Saunders Company.

Magnetic particles are useful for simple and efficient nucleic acid extraction. To achieve fully automated nucleic acid extraction and purification using magnetic particles, a new method for operating magnetic particles, Magtration Technology, was developed. In this method, magnetic separation is performed in a specially designed disposable tip. This enables high recovery of magnetic particles with high reproducibility. The features of this technology are (i) a simple mechanism for process control and (ii) flexible software to enable adaptation to commercially available reagents. Automated instruments based on Magtration Technology were developed and used for nucleic acid extraction. Total DNA, total RNA and plasmids were purified by Magtration Technology at an efficiency comparable to that of manual methods.

Thanks to various technical innovations and advances in instrumentation, laparoscopic surgical intervention is now possible for certain congenital anomalies in children. To test the applicability of laparoscopic surgery in neonates, we reviewed our personal experience of neonatal laparoscopic surgery, focusing on cardiopulmonary function, surgical procedures, problems with devices, and degree of associated surgical stress.We performed 65 laparoscopic procedures in neonates. Their ages ranged from 2 to 30 days old, and their body weights ranged from 1,980 to 4,780 g. All 65 laparoscopic procedures were carried out without mortality or serious morbidity.As complications, we encountered four cases of hypothermia due to rapid insufflation of carbon dioxide (CO(2)). We also found that relative hypercapnea (increase in end-tidal CO(2) as high as 61 mmHg) developed unless hyperventilation and a relatively high peak insufflation pressure were maintained during pneumoperitoneum. No cardiac depression developed at this insufflation pressure. Fluid and electrolyte balance during our cases of newborn laparoscopic surgery, as well as the doses and volumes of fluid and electrolytes administered, were identical to those required for open surgery. Interleukin-6 (IL-6) was measured serially to estimate the degree of associated surgical stress and was found to be significantly lower in neonates who had received laparoscopic procedures than in those who had received open procedures.Laparoscopic surgery can be carried out safely even in neonates.

Background/Purpose: Magnetic resonance cholangiopancreatography (MRCP) is an emerging tool for the noninvasive evaluation of the pancreaticobiliary tree. Methods: Non-breath-hold MRCP was used in three children to evaluate choledochal cyst; a first for this new modality of diagnostic imaging. In all cases, the intrahepatic and extrahepatic bile ducts, and the pancreatic duct were clearly visualized. Results: Two cases were found to have a fusiform choledochal cyst, and non-breath-hold MRCP demonstrated pancreaticobiliary malunion and a long common channel. In the remaining case, the size and location of the huge cyst prevented visualization of any pancreaticobiliary malunion. Endoscopic retrograde cholangiopancreatography (ERCP) in this patient failed to provide any additional information. All patients underwent cyst excision with hepaticoenterostomy, and made an uneventful recovery. Conclusions: Our initial experience suggests that non-breath-hold MRCP is a reliable method for the diagnosis of choledochal cyst in children and could replace ERCP.

In the long-term follow-up of patients with choledochal cyst, postoperative ascending cholangitis and/or stone formation in the intrahepatic bile ducts (IHBD) owing to anastomotic stricture present serious problems. To prevent the formation of anastomotic strictures, some surgeons recently have performed hepaticoenterostomy at the hepatic hilum, with a wide stoma, in all patients with choledochal cyst. The authors of the present study review the surgical procedures performed on a total of 180 children with choledochal cyst and discuss the treatment of choice, with special reference to the types of hepaticoenterostomy. The medical records and radiographs of all patients treated for choledochal cyst between January 1964 and December 1993 at the authors' institutions were reviewed. A total of 180 patients (mean age at time of surgery, 4.3 years) had follow-up for a mean of 11.1 years; 174 of them had cyst excision and hepaticoenterostomy, and six had cystoenterostomy. Of the 174 patients who underwent cyst excision, 171 had a conventional hepaticoenterostomy; two had an intrahepatic cystoenterostomy, and one had a hepaticoenterostomy at the hepatic hilum. IHBD stones with or without cholangitis developed postoperatively in four (2.3%) of the 171 patients who had conventional hepaticoenterostomy. The age at time hepaticoenterostomy of these four patients was 12, 7, 16, and 6 years. Postoperative IHBD stone formation and cholangitis were not found in 121 patients under 5 years of age. The authors recommend conventional hepaticoenterostomy as the treatment of choice for children with choledochal cyst. Hepaticoenterostomy at the hepatic hilum is indicated in only selected cases.

Tubed musculocutaneous flap has never been used to replace a circumferential defect of the thoracic esophagus in adults or children. The aim of this study was to examine whether a tubed latissimus dorsi musculocutaneous flap(TLDMF) can be used to repair a long gap defect of the thoracic esophagus. In 14 puppies with an average weight of 4.9 kg, part of the esophagus (two vertebrae in length) was excised through a right thoracotomy. A latissimus dorsi musculocutaneous flap was introduced into the thoracic cavity. The cutaneous layer was rolled into a tube and interposed in the space of the excised esophagus. The muscle layer was wrapped around the anastomosis. Three puppies died of operative complications, such as a minor anastomotic leakage and postoperative bleeding. One died of an unknown cause. Ten puppies were studied postoperatively with a barium meal, endoscopic examination, and autopsy. The management of these puppies over 4 months is described. It proved possible to replace a long gap thoracic esophageal defect with a TLDMF, which was safe, easy to be transferred, and obviated a laparotomy. Thus, this technique might offer an alternative method to bridge a long gap in patients with esophageal atresia or severe stenosis.

The authors report a case of biliary atresia (BA) with duplication of the common bile duct. A 1-month-old girl was referred for investigation of persistent jaundice. BA was suspected and confirmed with intraoperative cholangiography. A portoenterostomy was performed at 50 days of age. During dissection of the fibrous remnant of the common bile duct, a separate fibrous bile duct remnant running in parallel on the left, was identified. Histologically, there was bile duct proliferation at the porta hepatis of the left bile duct remnant. A diagnosis of BA with duplicated common bile duct was made. Postoperative course was uneventful, and at a follow-up assessment at 7 months, she was jaundice free, and her progress has been unremarkable.

A pair of dizygotic twins who were both found to have congenital biliary dilatation, but of different types, is reported. This case is of academic interest from an etiologic point of view.