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We investigated how the influence of natural exploratory gaze behaviour on postural control develops from childhood into adulthood. In a cross-sectional design, we compared four age groups: 6-, 9-, 12-year-olds and young adults. Two experimental trials were performed: quiet stance with a fixed gaze (fixed) and quiet stance with natural exploratory gaze behaviour (exploratory). The latter was elicited by having participants watch an animated short film on a large screen in front of them. 3D head rotations in space and centre of pressure (COP) excursions on the ground plane were measured. Across conditions, both head rotation and COP displacement decreased with increasing age. Head movement was greater in the exploratory condition in all age groups. In all children-but not in adults-COP displacement was markedly greater in the exploratory condition. Bivariate correlations across groups showed highly significant positive correlations between COP displacement in ML direction and head rotation in yaw, roll, and pitch in both conditions. The regularity of COP displacements did not show a clear developmental trend, which indicates that COP dynamics were qualitatively similar across age groups. Together, the results suggest that the contribution of head movement to eye-head saccades decreases with age and that head instability-in part resulting from such gaze-related head movements-is an important limiting factor in children's postural control. The lack of head stabilisation might particularly affect children in everyday activities in which both postural control and visual exploration are required.

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In the present study we aimed to track the influence of natural gaze behaviour on postural control from early childhood into adulthood. We measured time series of centre of pressure (COP) as well as head movement in three children groups aged around five (n=16), eight (n=15), and eleven (n=14) and in one group of young adults (n=15) during quiet stance with eyes closed, gaze fixed on a dot, and with gaze shifts between two dots. We adopted magnitude and irregularity of COP displacement as indexes of postural control and cross correlation between COP displacement and target oscillation as an index of the dynamical coupling between the postural and visual systems. Magnitude and irregularity of COP displacement decreased with age, which suggests a steady improvement of postural control from five to beyond eleven years of age. Cross correlations were weak and relative phases highly variable across age groups. Across conditions, and most prominently in the gaze shift conditions, 5-year-olds showed both more head movement and lower postural stability than other age groups. Finally, only in 5-year-olds did we find a marked deterioration of postural stability with gaze shifts. We thus conclude that excessive head movement, particularly during gaze shifts, may be a primary cause of lower postural stability in young children compared to older children and adults.

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BACKGROUND: Intestinal neuronal dysplasia (IND B) is still a subject of controversy. The aim of this paper is to review the present state of knowledge on IND B. A summary is given of the technical and diagnostic criteria which have to be considered in order to arrive at a reliable diagnosis. In addition, the available therapeutic interventions are discussed. METHODS: Between 1992 and 2001, 3984 colonic mucosal biopsies from 1328 children were investigated. Nerve cell staining was performed on native tissue sections: 15 microm thick cryostat sections, which, after spreading and drying on a microscopic slide, have a final thickness of 4-5 microm, with dehydrogenase reactions (lactic dehydrogenase, nitroxide synthase, succinic dehydrogenase). The biopsies were taken 8-10 cm above the dentate line (proximal to the ampulla recti, because of the caudo-cranial increase of giant ganglia proximal to the 4 cm biopsy) with a sufficient amount of submucosa. The criteria for IND is 15-20 % submucosal giant ganglia with more than eight nerve cells in 30 sections of a single biopsy (i.e. four to seven giant ganglia). RESULTS: The diagnosis of IND B is quantitative. A diagnosis of IND B was made over the past 10 years in 51 Hirschsprung resections (about 5 per year; 6 % of all Hirschsprung cases), and in 92 children with chronic constipation (about 9 children per year; 2.3 % incidence). Up to their fourth year of life, most children with isolated IND can be treated conservatively. This is due to the delayed maturation of the enteric nervous system which is characteristic of IND B. Only children who showed an additional hypoplastic hypoganglionosis were treated surgically. Children with Hirschsprung's disease (HD) and IND B proximal to the aganglionosis often showed, in those cases with a disseminated IND, postoperative disturbances in intestinal motility. CONCLUSION: The diagnosis of IND B requires that biopsies are taken proximal to the ampulla recti (about 8-10 cm above the dentate line) with a sufficient amount of submucosa. The biopsies must be cut rectangular to the surface of the mucosa. A diagnosis of IND B can be made only if, in the submucosa of 30 serial sections, 15-20 % of all ganglia are giant ganglia with more than eight nerve cells. Ganglioneuromatosis (MEN2B) must be clearly differentiated from IND. The clinical course of IND B depends on the extent of disturbed bowel innervation, the severity of motility failure, and the coexistence of MH. The conservative management of isolated IND is possible in most children. In individual cases, however, a transient enterostomy or a segmental resection is unavoidable.

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The peristaltic movement of the gut is a function of the alternating contraction and relaxation of circular and longitudinal muscles. This movement is induced by a tendon-like connective-tissue net (TCTN) in the circular and longitudinal muscles, which are both rooted in a connective-tissue plexus layer (CTPL). In children with a therapy-resistant aperistaltic or hypoperistaltic syndrome who had normally-developed enteric innervation, a lack of the TCTN in the muscularis propria was observed. Over the last 2 years, 241 children with chronic constipation were investigated histopathologically; 46 children surgically treated by partial resection of the gut or diagnostically investigated by whole-mount biopsy. Fifteen children had a hypoperistalsis syndrome and 3 had an aperistalsis syndrome. All specimens were native and cut in a cryostat. Enteric innervation was examined by acetylcholinesterase and dehydrogenase reactions. The TCTN in the muscularis propria was stained with picric acid/sirius red. In the children with an aperistalsis syndrome, a complete lack of the TCTN in circular and longitudinal muscles was observed. A CTPL was not developed. The children with a hypoperistalsis syndrome had no CTPL, but had a partly-developed TCTN in the circular and longitudinal muscles, which gradually faded in the direction of the plexus layer. Independent of a well-developed enteric nervous system, a lack of the TCTN in longitudinal and circular muscles and a missing CTPL (aplastic desmosis) abolishes the coordinated peristaltic movement of the gut. An isolated lack of the CTPL in the myenteric plexus (hypoplastic desmosis) results in a hypoperistalsis syndrome. An anomaly of the TCTN in the muscularis propria disturbs gut-muscle mechanics, and is another cause of gut dysmotility.

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A 45,X/46,Xidic(Y)(q11.2) mosaicism was found in a 4-year-old boy. The clinical appearance was characterized by bilateral cryptorchidism, penoscrotal hypospadias, short penis, and coarctation of the aorta. The latter is the only abnormality also seen in Turner syndrome. A biopsy of the gonads revealed normal prepubertal testicular tissue. A chromosome analysis in all boys with penoscrotal, scrotal, or perineal hypospadias and a thorough examination of the heart in children with 45,X/46,XY mosaicism are recommended.

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Hypoganglionosis of the myenteric plexus of the colon is not clearly defined and seldom investigated. Colon segments from 15 children with an extended oligoeuronal hypoganglionosis up to the proximal resection end were morphometrically studied and compared to normally innervated colon segments. The study was performed with resected specimens from 7 children with isolated hypoganglionoses, 8 children with a Hirschsprung-associated hypoganglionosis, and 12 colon segments with normal innervation. The resected colon specimens were caudo-cranial coiled. The native tissue was frozen at -80 degrees C on a cryostat carrier and cut at -20 degrees C in 15 microns-thick sections (equivalent to 4-5-micron-thick paraffin sections). The air-dried sections underwent an enzyme-histochemical procedure for an acetylcholinesterase reaction to stain the parasympathetically innervated myenteric plexus. For histological identification and morphometric measurements, ganglia and nerve cells were selectively stained using a lactic dehydrogenase reaction. The morphometric measurements were performed with an optic-electronic image analysis system that determined ganglion size, ganglion distances, nerve cell number per ganglion, and ganglion number per mm colon. The results showed that hypoganglionosis of the myenteric plexus is characterised by a 42% decrease in plexus area and a 55% decrease of the nerve cell number per mm length of colon. The number and area of myenteric ganglia showed a decrease of 59% and a doubling of the ganglion distances. The histopathological diagnosis of a hypoganglionosis of the colon was not necessarily an indication of a chronic constipation, but rather an indication of a disposition for constipation. A chronic constipation is often caused by a long hypoganglionic segment proximal to a resected short Hirschsprung segment.

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Only a few reports of intestinal hypoganglionosis (H) have been reported, mainly because of diagnostic difficulties. Persistent stool retention since birth and increasing distension of the colon are common to Hirschsprung's disease. It is extremely difficult to establish the diagnosis histochemically unless full-thickness biopsies are performed. Morphometric examination is essential for objective confirmation of the diagnosis. In H, the number of ganglion cells per longitudinal centimeter is decreased by a factor of 2, and the development of nerve fibers is scarce. Manometric findings are inconsistent, and barium studies of the colon and rectum may not provide answers regarding the underlying condition. Treatment of localized disease consists of resection followed by a Soave-type pull-through procedure. The etiology of H is still unknown, but an inborn hypoplasia of the parasympathetic myenteric plexus may be responsible. Among 353 rectal biopsies, 15 cases of H were detected. In seven children, it occurred as an isolated form, in four it was combined with distal aganglionosis, and in four it involved proximal intestinal neuronal dysplasia as well. After proper bowel preparation and resection of the hypoganglionic segment, the outcome was good for all patients. Secondary operations consisted of temporary colostomy in one patient due to anastomotic complications. One patient had an adhesive small bowel obstruction. In two patients with disseminated H of the small bowel and colon, resection was not indicated. Both are dependent on partial parenteral feeding since ages 9 and 3 years. It is expected that more cases of H will be diagnosed in the future, especially if diagnostic measures are improved. The diagnosis is likely in cases of persistent stool retention despite resection of an aganglionic segment.

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The Palomo procedure has often been criticized with regard to possible atrophy of the testis. Measuring the testicular volume is mainly used in pre- and postoperative assessment. Evidence concerning fertility remains unclear. The aim of this study was to learn whether now-adult former patients had any disturbance of their testicular growth and/or fertility. Out of 79 patients operated upon with Palomo's procedure between 1979 and 1990, 33 could be evaluated. They all had grade II or III left-sided varicoceles. Investigations consisted of: the patient's history, testicular-volume measurement by means of an orchidometer (OM) (Prader) and ultrasonography (US), and semen analysis (27/33) 6-17 years after surgery. No recurrence of grade II varicoceles was observed. Only 1 of the 33 patients might have had testicular atrophy, yet he had already fathered 3 children! Twenty-three had a normal sperm count and 24/27 showed normal sperm motility. Eight hydroceles were either present at the time of investigation or had been operated upon in the past. Estimations of testicular volume by OM and US showed significant differences between the two methods concerning volume and relation of right to left side. In general, the volume was overestimated by the OM. The study shows that in boys the simple surgical technique proposed by Palomo has - in the long run - no disadvantages for testicular development and sperm production. Fertility should therefore not be compromised.

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A 31-year-old man who died of metastatic adenocarcinoma of the sigmoid colon had undergone bilateral ureterosigmoidostomy for exstrophy of the bladder 20 years earlier. The patient never underwent a colonoscopy. Neoplastic transformation at the ureterosigmoid anastomosis must be considered as a possible severe complication, and therefore, periodic follow-up of these patients is mandatory.

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In addition to their original healing-mission, physicians gain more and more responsibility in health politics including most important aspects like education and medical ethics. Recent developments and possibilities in prenatal diagnostics, molecular biology and in-vitro-fertilization demand clearcut positions from the medical staff. Political evaluation of costs in health care systems concerns analysis of the most common factors responsible for the increasing costs. High expectations and demands of the patients are one reason, other are excessive use of new technologies, increase of the aged in the population and growing cost for liability cases. Mechanisms for the down-regulation of costs are restricted. The so called free market in health care such as premium-competition of health insurance point out more theoretical than practical aspects. The Health insurance law (KVG) by increasing the extent of services has contributed to a further increase of costs instead of lowering them. Shifting from hospitalization to out-patient treatment and reducing beds for acute services could lower hospital costs further. AIDS, Drug-politics and environmental destruction, three actual plagues, represent further political challenges for physicians. For the future a reasonable politic involving a better motivated medical corps has to be promoted. To this end first personal structures should be strengthened by help of new ethical view points. Future medicine should be complex, patient-oriented-and remain affordable. Therefore medical responsibility in political development is mandatory.

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Long-gap esophageal atresias (EA) generally require surgical substitution using colon, jejunum, or a portion of the stomach. In these procedures, as in total gastric pull-up operations, the distal portion of the esophagus is sacrificed. Experimental studies on cadaver stomachs have shown that retrosternal transfer of the distal esophagus with preservation of all esophageal portions is possible when the lesser curvature is incised diagonally, provided the collateral circulation via the left gastric artery (LGA) is preserved. A tension-free esophageal anastomosis is then carried out intrathoracically or cervically. This technique was employed successfully in eight children. In two cases ligation of the LGA alone was sufficient; in six an additional incision in the lesser curvature was required to achieve adequate length. This procedure is advantageous in that all portions of the esophagus are preserved and, due to the retrosternal position, a thoracotomy is unnecessary. The morbidity is significantly lower than that associated with all the other substitution techniques. The main complications included cervical anastomotic leaks, which closed spontaneously, and stenoses that required bouginage. There was no mortality. From our experience to date, it can be concluded that esophageal anastomosis is possible in long-gap EA after incising the lesser gastric curvature, and that substitution plasties can be avoided.

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Nausea and vomiting after anaesthesia and surgery in children remains a major problem. The following survey studies the frequency of postoperative vomiting and relates it to the anaesthetic technique, the surgical procedure, and postoperative analgesia. During one year, September 1989 until September 1990, 2370 surgical patients requiring anaesthesia were studied prospectively with the following protocol: 1) patient data, surgery and anaesthesia technique; and 2) postoperative follow-up were registered. Outpatients were followed up by telephone. The overall incidence of vomiting was 19.5%, which was lower than in other studies. An increased incidence of vomiting was found in children over 2 years of age, after certain operative procedures, and after general anaesthesia. Furthermore, postoperative opioid administration on the ward increased the risk of vomiting. Despite the low overall incidence of vomiting in our study, we still found a high frequency after certain surgical procedures. The use of regional anaesthesia, prophylactic antiemetic medication, and the introduction of new anaesthetics, may help to reduce the sometimes high incidence of postoperative nausea and vomiting in paediatric patients.

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The treatment of long bone fractures in children has been substantially changed within the past five years. The aim at conservative management, including closed reduction, retention and fixation, remains undebatable. Considerations of the biological and biomechanical healing process and the aim of short hospitalization and early mobilization have lead to an increased use of the intramedullary nailing technique. Simultaneously, the indication for osteosynthesis with plates has been limited to more restricted indications. The first multicentric results of the international working group of pediatric traumatology, together with our personal experience over 20 years, form the basis of a therapeutic concept for long bone fractures in children. Prospective studies of these recommendations will continuously analyse the quality assurance of fracture treatment.

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