Endochondral ossification of costal cartilage is arrested after chondrocytes have reached hypertrophic stage of late differentiation.

Late cartilage differentiation during endochondral bone formation is a multistep process. Chondrocytes transit through a differentiation cascade under the direction of environmental signals that either stimulate or repress progression from one step to the next. In human costal cartilage, chondrocytes reach very advanced stages of late differentiation and express collagen X. However, remodeling of the tissue into bone is strongly repressed. The second hypertrophy marker, alkaline phosphatase, is not expressed before puberty. Upon sexual maturity, both alkaline phosphatase and collagen X activity levels are increased and slow ossification takes place. Thus, the expression of the two hypertrophy markers is widely separated in time in costal cartilage. Progression of endochondral ossification in this tissue beyond the stage of hypertrophic cartilage appears to be associated with the expression of alkaline phosphatase activity. Costal chondrocytes in culture are stimulated by parathyroid hormone in a PTH/PTHrP receptor-mediated manner to express the fully differentiated hypertrophic phenotype. In addition, the hormone stimulates hypertrophic development even more powerfully through its carboxyterminal domain, presumably by interaction with receptors distinct from PTH/PTHrP receptors. Therefore, PTH can support late cartilage differentiation at very advanced stages, whereas the same signal negatively controls the process at earlier stages.

Skeletal muscle tissue engineering using isolated myoblasts on synthetic biodegradable polymers: preliminary studies.

Skeletal muscle is responsible for the control of voluntary movement and the maintenance of structural contours of the body. Muscle loss or deficiency is encountered in various pathological states, and attempts to correct them have been employed with limited success. The aim of the present study was to tissue engineer three-dimensional vascularized skeletal muscle using isolated myoblasts attached to synthetic biodegradable polymer for tissue replacement in the enhancement of muscle regeneration. Myoblasts derived from neonatal rats (3-5-day-old), Fisher CDF-F344, were seeded onto polyglycolic acid meshes and implanted into the omentum of syngeneic adult Fisher CDF-F344 rats. Rats were sacrificed on day 30 and day 45 after the transplantation, and the cell-polymer constructs were harvested for morphological analysis. Histological analysis of the constructs were performed by hematoxylin and eosin, and immunohistochemical staining was positive for alpha sarcomeric actin and desmin skeletal muscle marker. Viable myoblasts organized between strands of degrading polymer mesh formed the new tissue, and vascularization of the entire construct was observed. Organization of neomuscle strands surrounded by vascularized tissue composed of degrading polymer and fusing myoblasts demonstrated the ability of myoblast constructs to survive, reorganize and regenerate tissue-like structures. Since myoblast transplantation to date has been limited to the cellular level of replacement, myoblast-polyglycolic acid constructs may be useful in defining the application of tissue engineering for future skeletal muscle transplantations.

Experience with a cholinesterase histochemical technique for rectal suction biopsies in the diagnosis of Hirschsprung's disease.

Cryostat sections from 160 rectal suction biopsies were stained for cholinesterases by the method of Karnovsky and Roots (1964) in an attempt to facilitate the diagnosis of Hirschsprung's disease. The method proved at least as reliable as experienced assessment of paraffin haematoxylin-eosin sections, and appeared to offer the advantages of reduced scanning fatigue and superior demonstration of the increased cholinesterase-positive nerves in Hirschprung's disease. Contrary to the findings of Meier-Ruge (1971) it was not possible to base a diagnosis on mucosal cholinesterase activity.

Octylcyanoacrylate tissue adhesive in the repair of pediatric extremity lacerations.

Lacerations comprise a significant number of emergency department referrals for pediatric patients. Management of lacerations with sutures involves the use of needles and the injection of local anesthetic and represents a unique challenge in the wound management of an already distressed and frightened child. Octylcyanoacrylate, a new-generation, medical-grade tissue adhesive, has been found to be an effective alternative to replace skin sutures on virtually all facial lacerations and has been employed in low-skin tension wound management. Its use, however, has generally been avoided in the management of high-skin tension lacerations. Over the last 10 months, 32 children with high-skin tension (hand, feet, and over joints) lacerations were managed at our center by octylcyanoacrylate tissue adhesives. Skin closures and splints were applied to restrict movement of the affected area to overcome the limitation of adhesive application. Octylcyanoacrylate adhesive applied with optimal immobilization was found to be an effective method of skin closure in high-skin tension lacerations. Advantages of tissue adhesives for incision and laceration include quick application, excellent cosmetic results, patient preference, and cost effectiveness.

Omphalocele: clinical review and surgical experience using dura patch grafts.

Over a period of 15 years we surgically treated 50 cases of omphaloceles. The pathology occurred more frequently in boys (n = 30) than in girls (n = 20). The mean birth weight was 2995 g and mean gestational age was 38 weeks. Four infants (8%) were delivered vaginally and the rest (92%) by cesarian section. Eleven infants (22%) underwent primary closure, but in 20 infants (40%) with larger defects a primary closure of the skin was possible; however, a single solvent-dried dura graft implant was employed for the fascia enlargement. The remaining 19 infants (38%) had extremely large defects, and optimal closure of the defect required a two layered graft implantation. Twenty-five infants (50%) had associated anomalies, the majority being congenital cardiac anomalies. Five patients (10%) required secondary laparotomies due to bowel associated complications. Four patients (8%) experienced non-bowel-associated complications. The average postoperative mechanical ventilation required was for a period of 3.2 days and the average hospital stay was 45.7 days. The overall mortality rate was 8% (n = 4) and was largely due to severe congenital heart anomalies. Solvent-dried dura was successfully employed in the management of the larger defects with no major complications; only one patient (2%) had a local abscess around the area of the implant and was managed conservatively. Our experience favors the employment of solvent-dried dura graft implants for the repair of large omphaloceles. The solvent-dried dura grafts are biomaterials that promote rapid scar formation and integration with the adjacent skin tissue and do not produce any foreign body reactions at the site of implantation.

Morphologic findings of chest deformities in children corresponding to the Willital-Hümmer classification.

The clinical classification of funnel and pigeon chest deformities can be subclassified by means of special measurements of the chest. This simple technique makes it possible to differentiate sternocranial, sternocaudal, infrasternal, symmetrical, and asymmetrical marginal and peripheral deformities. This further classification also includes deformities of the vertebral column and deviatory development. The exact analysis of the abnormal chest in three different planes can be performed by means of external chest-wall measurements.

Intraanal ultrasound: a new aid in the diagnosis of pelvic processes and their relation to the sphincter complex.

Intraanal ultrasound provides a very accurate structural analysis of the continence organ. In addition it proved to give excellent pictures of solid or fluid intrapelvic, particularly retrorectal, structures. It is superior to computed tomography and magnetic resonance imaging (requiring anesthesia), because the scanner is very close to the structures in question. This allows high scanner frequencies with resolutions of 0.9 mm and better. It is a quick method, avoiding radiation, and can be safely repeated as often as necessary.

Delayed primary reconstruction of an esophageal atresia with distal esophagotracheal fistula in an infant weighing less than 500 g.

Delayed primary reconstruction of an esophageal atresia (Vogt IIIb) was undertaken in an extremely small-for-date baby (second twin, 36th week) with a birth weight of 445 g. After initial insertion of a gastrostomy under local anesthesia on the 29th day of life, ligation of the fistula and end-to-end anastomosis were performed by transpleural access (weight then, 535 g). There were no complications related to the operative procedure. The baby weighed 1,600 g at the age of 8 months.

Technical aspects of laparoscopic splenectomy in children.

Different authors reported about their experiences in laparoscopic splenectomy. The preparation of vessels and ligaments are feasable without major problems. Nevertheless the handling of the organ during the operation and during splenic extraction can be very difficult, especially in larger organs. The authors report experience with the technique of laparoscopic splenectomy and describe a new technical aspect in handling the spleen during this procedure. A loop of an umbilical band is used for retracting the organ during the preparation and placing the spleen into a sterile bag for the removal of the organ. This device helps prevent damages to the capsule caused by forceps. Large organs can be placed into the pelvis, and the bag is placed and opened in the upper abdomen. The authors used this technique successfully in seven patients. The results are compared with previous experiences.

Possibilities of scar treatment after thoracic surgery.

During a ten year observation period it was found that scar formation after thoracic surgery is influenced by various factors: metabolism, operative technique and factors of a general nature. On the basis of these findings, a study was carried out to investigate the effect of the scar-specific Contractubex gel (Merz+Co., D-Frankfurt/Main), containing 10% onion extract, 50 U sodium heparin per g of gel and 1% allantoin, in the treatment of children who underwent thoracic surgery and to evaluate its effect on scar development. Before and during the six-month treatment period, both macromorphology and scar colour were assessed; furthermore, a global evaluation of the therapeutic result was made. Additionally, the scars were characterized after a six-month treatment-free follow-up period. The results of 38 Contractubex-treated and 27 untreated patients were compared. In the treated scars, the global evaluation of the therapeutic result was better than in the untreated scars. In the Contractubex group, the rating was "good" and "very good" in 84% of cases, as compared to 59% of the untreated cases. In the treated group, the increase in scar size was markedly lower than in the untreated patients. The treated scars showed a tendency towards quicker paling than the untreated scars. In the treated group, the conversion of primary physiological scars to unphysiological scars (hypertrophic or keloidal scars) was less frequent than in the untreated group. The tolerability of the product was very good in 37 of the 38 treated patients, and good in one patient. All scar-specific effects of Contractubex continued to persist after the end of treatment.

Efficacy of Contractubex gel in the treatment of fresh scars after thoracic surgery in children and adolescents.

Scar development was investigated in 45 young patients who had undergone thoracic surgery. Patients were randomly assigned either to a group which was treated topically with Contractubex gel (Merz + Co., D-Frankfurt/Main), containing 10% onion extract, 50/U of sodium heparin per one g of gel and 1% allantoin, or to a group receiving no treatment. The treatment began on average 26 days after the operation and was continued for one year. The scars of all treated and untreated patients were evaluated at monthly intervals. The appearance of the scar, including scar type and scar size as well as scar colour, was assessed by the physician. A reduction of the increase of scar width was seen in the Contractubex-treated group as compared with the untreated group. Further, physiological scars and skin-coloured scars were more frequent in the treated group than in the untreated group. Hypertrophic or keloidal scars were less frequent in the treated group. No differences in scar length and scar height were seen. At the end of the observation period, the clinical course of scar development was rated as "very good" or "good" in more than 90% of the treated patients, "good" in less than 40% and "moderate" or "bad" in more than 60% of the untreated cases. The tolerability of the drug was "good" or "very good" in all cases. In conclusion, Contractubex gel is useful in scar treatment after thoracic surgery.

The rat esophagus: ultrastructure and radiological aspects of tissue response after 1320 nm Nd:YAG laser irradiation.

Morphological tissue response towards laser treatment was investigated in the esophagi of adult Wistar rats by light- and transmission electron microscopy. The specimens were fixed by perfusion immediately, 2 days and 14 days after laser treatment in order to assess different stages of the healing process. The epithelium of the lasercentre was completely destroyed in the immediate group. The connective tissue showed damaged cells, fused collagenous fibres and occluded blood vessels. Smooth muscle cells presented a vacuolated sarcoplasm and pycnotic nuclei. The cross striation of skeletal muscle cells had disappeared and their nuclei were karyolytic. In a distance of 4 mm from the lasercentre all wall tissues had an almost normal appearance. After 2 days the morphological feature of the lasercentre was the same as in the immediate group. In a distance of 2 mm some layers of flat and intact epithelial cells were observed below the necrotic epithelium. The adjacent connective tissue was infiltrated by inflammatory cells. After 14 days the formation of granulation tissue had caused an occlusion of the lumen in the lasercentre. In a distance of 2 mm the lumen was patent and the wall tissues had been partly restored. As the rat esophagus serves as a model for esophagotracheal fistulae in newborn children we assume the 1320 nm Nd:YAG laser to be a possible application in occlusion of these fistulae.

[The cell response of rat esophagus after intraluminal irradiation with Nd-YAG-laser (1064 nm) after various postoperative times: a light and electron microscopic study]. / Die Gewebeantwort des Rattenösophagus nach intraluminaler Bestrahlung mit Nd-YAG-Laser (1064 nm) zu unterschiedlichen postoperativen Zeitpunkten: Eine licht- und elektronenmikroskopische Studie.

The esophagi of Wistar rats were irradiated by a Nd-YAG-laser and studied by light and transmission electron microscopy immediately, 2 days and 14 days after the operation. In the immediate group the lasercentre showed a destruction of the stratified epithelium. On the contrary the cells and fibres of the underlying connective tissue were hardly affected. In the lasercentre we have found occlusion of microvascular lumina. Both the layer of smooth muscular tissue and the layer of skeletal muscular tissue showed defects in their myofilaments and altered nuclei. The damage of the skeletal muscle fibres extended up to 4 mm distant from the lasercentre. After 2 days a migrating epithelial sheet was present below the necrotic epithelium and an inflammatory reaction was found in the connective tissue. After 14 days a new regenerated epithelium and an underlying granulation tissue had caused a stenosis of the esophageal lumen. The smooth and striated muscle fibres also showed signs of regeneration. We assume a high regenerative capacity of all involved tissues.

Laparoscopic appendectomy in children with Enterobius vermicularis.

As surgeons gain more experience with laparoscopy in children, it is becoming apparent that one of the best applications of the technique is for appendicitis. The advantages of laparoscopic appendectomy include a better cosmetic result, particularly in young female patients, a shorter recovery time, and an early return to normal activities. In the differential diagnosis of appendicitis, the association of Enterobius vermicularis (pinworms) inflammation in the pediatric age group is not uncommon. The endo-loop technique for laparoscopic appendectomy is the standard technique used in our department. In three patients with E. vermicularis undergoing appendix removal using this technique, pinworms were found to be set free into the abdomen after dividing the appendix between the loop ligatures. Bipolar coagulating forceps were used carefully to thermally desiccate the worms, which were then removed using a blunt grasper. E. vermicularis being released into the abdomen in children undergoing laparoscopic appendectomy using the endo-loop technique has not been reported. Careful evaluation of the appendix stump and simple but careful thermal desiccation and removal of pinworms, if present, must be considered when using the endo-loop technique.

Long-term results of Rehbein's procedure: a retrospective study in German-speaking countries.

AIM: In contrast to other countries, no collective study of Rehbein's procedure in German-speaking nations has been performed. Therefore, our intention was, analogously to Goto and Ikeda's (10) Japanese study in 1984, Kleinhaus's (13) study on Swenson's procedure in 1979, Bourdelat's (2) French-Canadian investigation into Duhamel's technique in 1997 and Martuciello's (11) and Teitelbaum's (16) follow-up in the year 2000, to perform a follow-up study of Rehbein's technique of deep anterior resection. METHODS: The data of 200 patients from 22 German-speaking centers in Switzerland, Austria and Germany were collected. These data were gathered by questionnaire and the children were followed up in the individual participating hospitals for at least 3.5 years after the procedure. The procedure was performed between 1993 and 1997, over a 5-year period. The questionnaire contained 74 items including anamnestic data, diagnostic postoperative treatment and reoperations. RESULTS: Concerning the incidence of anastomotic leaks and resolving anastomotic strictures there was no significant difference between the results in our series and those of the collective analyses made by Hofmann von Kap-herr (7), Holschneider (9) and Sherman (18). In 6.6 % of the 191 patients an anastomotic leak and in 9.9 % a rectal stricture, which had to be dilated, was observed. Concerning late complications, 22.8 % of the children suffered from constipation, 4.3 % from encopresis, 10.6 % from enterocolitis and only 0.5 % from enuresis. The frequency of constipation diminishes over the years. A comparison of the different large series in the literature clearly shows that the incidence of constipation is higher after Rehbein's procedure and the frequency of urinary incontinence and encopresis higher following Swenson's, Soave's and Duhamel's techniques. The incidence of enterocolitis is less after Rehbein's procedure than after Swenson's, Soave's and Duhamel's techniques. CONCLUSIONS: The different results in the literature are due to the individual experience of the author, the very different follow-up methods and the date of follow-up. Therefore, the different results are hard to compare with our study. Nevertheless, Rehbein's anterior resection still could be presented as an adequate and important method to treat Hirschsprung's disease.

Tracheoesophageal anastomosis, continent gastrostomy and oesophagostomy--a new experimental model in minipiglets.

Tracheoesophageal fistulae endanger newborn children by aspiration pneumonia. An animal model of this dangerous malformation was thought to be impossible until now. By tracheoesophageal anastomosis, occlusion of the oesophagogastral junction, proximal cervical oesophagostomy and continent gastrostomy in 25 minipiglets a reliable model of tracheoesophageal fistula has been developed. After establishing the model in a pilot study the mortality following the establishment of this procedure was 5.6% and the minipiglets survived in excellent condition for 2-10 week periods under complete alimentary restriction and gastrostomy feeding. Therefore the method seems to be suitable for long-term investigations on major oesophagotracheal surgery.

Surgical repair of pectus carinatum.

Pectus carinatum represents a variety of protrusion deformities of the anterior chest wall. Although various non-operative methods of treatment have been employed, surgery has been widely accepted as the only effective method for the correction of pectus carinatum. We evaluate our 14 year single center experience of pectus carinatum correction on 111 patients using a uniform technique of internal stabilization employing stainless steel struts. Operative correction required double bilateral chondrotomy parasternally and at points of transition to normal ribs, followed by detorsion of the sternum, retrosternal mobilization and correction of the everted sternum as well as of the everted and inverted ribs. The mobilized sternum after incomplete wedge osteotomy was finally stabilized by one transternal and two bilateral parasternal metal struts. The corrections were completed with successful repair in 109 patients (98.2%). Major recurrences in 2 patients (1.8%) were corrected while mild recurrence were observed in 3 patients (2.7%).

Non-retractile foreskin: a single center 13-year experience.

BACKGROUND: Non-retractile foreskin comprise a significant number of referrals by pediatricians and general practitioners to pediatric surgical centers. In attempts to find alternatives to widely practised circumcision, various procedures have been developed over the years in order to relieve the non-fibrotic narrowing of the foreskin. PATIENTS AND METHODS: In a 13-year period from 1984-1997, we treated 2554 patients with non-retractile foreskin at our center. Dorsal relieving incision was the technique of choice and was performed in 2177 patients, circumcision in 73 patients and preputial adhesiolysis was sufficient to retract the foreskin in 284 patients. RESULTS: Satisfactory esthetic results, an extremely low rate of postoperative complications (1.8%) with a recurrence rate of only 0.8% (18 patients) was observed in our series with dorsal relieving incision. CONCLUSIONS: Dorsal relieving incision operation was found to be a less invasive, safe and effective procedure for non-retractile foreskin not affected by extensive secondary scarring. This technique has fewer complications in comparison to circumcision and can be performed as an ambulatory procedure.

Vascularized three-dimensional skeletal muscle tissue-engineering.

Medical science continues to battle against the loss or failure of organs or tissues. Since, skeletal muscle loss lead not only to the functional compromise of the affected site, but also a structural deformation; tissue engineering of skeletal muscle attempts to provide solutions to replace loss of tissue contour and function. In our study, myoblasts seeded onto polyglycolic acid (PGA) meshes were used to engineer skeletal muscle tissue in vivo. The cell-polymer constructs harvested after a period of 6-weeks were well vascularized three-dimensional structures with the ability to generate neo-muscle-like tissue. This is the first time that the ability of myoblasts to survive in vivo in the absence of mature skeletal muscle tissue was demonstrated. The successful ability to transplant myoblasts using biodegradable polymer strands without using the traditional transplantation buffer mediums as carriers was also employed for the first time.

[Surgery in childhood at the hospital for basic and routine general management]. / Chirurgie im Kindesalter im Krankenhaus der Grund- und Regelversorgung.

Pediatric surgery in general surgical hospitals involves treatment of blunt thoracic trauma, blunt abdominal trauma and acute abdominal and inguinal surgery. Special surgical techniques are: opening of the bursa omentalis to detect pancreas ruptures; partial liver resections in deep organ ruptures instead of wound readaptation due to postoperative bleeding, gall bladder fistulae and rising infections; organ-protecting spleen resections. Appendectomy is indicated in children in cases of non-inflammatory, congenital chronic abdominal pain (dissociated visceral growth); side-to-side anastomosis is contraindicated because of the "blind-loop syndrome". The megacolon detected intraoperatively has seven different causes necessitating a colostomy and further diagnostic procedures in special hospitals. Incarcerated hernias in newborns have a 6-times higher recurrence rate, Bassini operations are contraindicated.