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Site-specific delivery of angiogenic growth factors from tissue-engineered devices should provide an efficient means of stimulating localized vessel recruitment to the cell transplants and would ensure cell survival and function. In the present article, we describe the construction of a novel porous alginate scaffold that incorporates tiny poly (lactic-co-glycolic acid) microspheres capable of controlling the release of angiogenic factors, such as basic fibroblast growth factor (bFGF). The microspheres are an integral part of the solid alginate matrix, and their incorporation does not affect the scaffold porosity or pore size. In vitro, bFGF was released from the porous composite scaffolds in a controlled manner and it was biologically active as assessed by its ability to induce the proliferation of cardiac fibroblasts. The controlled delivery of bFGF from the three-dimensional scaffolds accelerated the matrix vascularization after implantation on the mesenteric membrane in rat peritoneum. The number of penetrating capillaries into the bFGF-releasing scaffolds was nearly fourfold higher than into the control scaffolds (those incorporating microspheric BSA and heparin but not bFGF). At day 10 posttransplantation, capillary density in the composite scaffolds was 45 +/- 3/mm(2) and it increased to 70 +/- 7/mm(2) by day 21. The released bFGF induced the formation of large and matured blood vessels, as judged by the massive layer of mural cells surrounding the endothelial cells. The control over bFGF delivery and localizing its effects to areas of need, may aid in the wider application of bFGF in therapeutic angiogenesis as well as in tissue engineering.

We add two cases of prenatally diagnosed late-onset isolated cystic hygroma to the eight cases reported previously in the English literature. The obstetrical significance, management, and outcome of this entity are reviewed. A retrospective study of late-onset isolated cystic hygromas delivered in one medical centre between 1978 and 1992 was made. The medical records of these newborns served as the basis of the present report. A Medline search of the English literature was carried out. Over a period of 15 years, we observed 11 cases of late-onset congenital isolated cystic hygroma, two of whom had prenatal sonographic diagnosis. In one case, a Caesarean section was performed due to a huge lesion. All cases underwent surgical excision with a favourable outcome. Of the eight prenatally diagnosed cases reported previously, one died at birth due to inability to ventilate and two required a tracheostomy. Late-onset isolated cystic hygroma should be differentiated from the early-onset nuchal cystic hygroma. The differential diagnosis is important, as late-onset isolated cystic hygroma does not require any prenatal intervention, but special awareness during labour and Caesarean section in extreme cases. Transport to a perinatal centre with expert neonatal, respiratory, and paediatric surgical care is recommended. The prognosis in general is favourable.

Heparanase (HPSE) is an endo-β-D-glucuronidase, which cleaves heparan sulfate in the extracellular matrix (ECM) and has pro-angiogenic and pro-proliferative properties. The aim of this investigation was to study the effect of HPSE on hepatocytes and endothelial cells (EC) during liver regeneration.Following 70% hepatectomy (PHP), rats were injected daily with 1-50μg HPSE/rat. Liver samples were stained with HE and anti-bromodeoxyuridine (BrdU) antibody. mRNAs of hepatocyte growth factor (HGF), stem cell factor, tumor necrosis factor (TNF)-α, interleukin(IL)-6, and cyclinD1 were tested by real-time qPCR. Matrix metalloproteinases (MMPs) were tested by gel zymography.Compared to the saline control, HPSE increased hepatocyte proliferation 24h, 48h and 72h after PHP, with the maximal effect found at 24h with 50μg HPSE (40.9±2.5% vs. 8.6±4.3%, p0.01 for BrdU staining; 5.5±0.9% vs. 0.8±0.5%, p0.05 for mitosis). Proliferation of the sinusoidal and the portal vein radical ECs was also increased (p0.05). HPSE caused a twofold increase in cyclinD1 mRNA (p0.05) and in pro-MMP-9 levels (p0.05). HPSE at all doses also caused significant reductions of TNF-α mRNA (p0.05) and IL-6 mRNA, and no change in HGF mRNA.HPSE enhances liver regeneration by inducing proliferation of hepatocytes and both sinusoidal and vascular ECs. Since the effect of HPSE on hepatocytes occurred earlier than that observed in ECs, this effect is not related to HPSE's effect on ECs. The mechanism of HPSE action is probably indirect and is mediated by HPSE-dependent ECM cleavage and the release of pre-existing enzymes.

The present study was undertaken to further explore the comparative dynamics of growth hormone-binding protein (GH-BP) in relation to the turnover of the GH-receptor (GH-R) in vivo in rabbits and rats. The strategy used was to examine the time course of hepatic GH-R turnover over a 3 h period after cycloheximide treatment, with simultaneous measurements of serum GH-BP level. In the rabbit we sampled multiple liver biopsies and serum samples consecutively from each animal. In the rat, experiments on individual animals were conducted for each time point. In the rat, both liver GH-R and serum GH-BP declined after cycloheximide injection following first-order kinetics. The t12 values for GH-R and GH-BP were 29.7–44.5 and 82.7–119.5 min (95% confidence limits), respectively. A significant positive correlation was found between rat liver GH-R and serum GH-BP (r = 0.85; p < 0.001). In contrast, the decline in rabbit liver GH-R, following cycloheximide treatment, was accompanied by simultaneous time-dependent accumulation of serum GH-BP. The t12 for rabbit serum GH-BP accumulation was 30.4–67.6 min. Scatchard analysis of [125I]hGH binding to rabbit GH-BP indicated that the binding capacity increased from 2818 ± 538 fmol/ml, at time zero, to 5236 ± 419 fmol/ml following 60 min cycloheximide treatment (p < 0.05). No significant changes in affinity were observed. Pooling all rabbit data points after cycloheximide injection, a significant negative correlation was found between liver GH-R and serum GH-BP (r = −0.58; p < 0.001). Thus, parallel disappearance of hepatic GH-R and serum GH-BP in the rat following cycloheximide treatment contrasts that in the rabbit, in which the decline in hepatic GH-R was accompanied by simultaneous time-dependent accumulation of serum GH-BP.

The role of the liver in regulating serum growth hormone-binding protein (GH-BP) was studied. We measured rat serum GH-BP and insulin-like growth factor 1 (IGF-1) 30 min to 96 h after 70% partial hepatectomy (PHP) or sham operation in adult male rats. Serum GH-BP declined sharply from 5.8 +/- 0.1% at baseline to 3.9 +/- 0.5% by 48 h following PHP. By 72 h serum GH-BP at baseline to 3.9 +/- 0.5% by 48 h following PHP. By 72 h serum GH-BP returned to baseline level and remained at that level 96 h postoperatively. In sham-operated female rats, serum GH-BP was about 2-fold higher than in males (10.5 +/- 1.46 versus 5.8 +/- 0.2%), whereas 24 h after hepatectomy a significant drop of about 50% was observed (p0.001). Serum IGF-1 decreased within 2-4 h postoperatively in both sham-operated and PHP groups, but thereafter was lower in the PHP rats, up to 48 h after operation, compared to sham-operated rats (p0.03). The study shows that the liver has an important role in the determination of serum GH-BP levels. The return to normal GH-BP level, even before the liver regained its full size following hepatectomy, suggests an increase in GH-BP production by the regenerating liver.

Upper pouch tracheoesophageal fistula (TEF) accompanying esophageal atresia (EA) occurs in less than 1% of all EA/TEF variants and could be easily missed after birth. To confront such diagnostic inaccuracy, perioperative tracheobronchoscopy (TBS) and preoperative upper pouch esophagogram (UPEG) have been proposed but are still controversial. We describe the role of UPEG and TBS, used early after birth, in two cases of EA/TEF with upper pouch TE fistulas with unusual high location (one intrathoracic, one subglotic). These upper TE fistulas were almost missed but ultimately detected very early while employing both UPEG and TBS, wherein UPEG was for the diagnosis of TEF and TBS for both intraoperative diagnostic confirmation and aid in TEF identification. We conclude that UPEG and TBS are complementary in detecting near-missed upper TE fistula accompanying EA. Such approach ensures early and accurate diagnosis of EA/TEF variants, thus preventing the complications of a missed congenital upper pouch TE fistula.

We have previously demonstrated that a spiral myotomy and delayed definitive procedure is a viable alternative for esophageal reconstruction in long-gap esophageal atresia. In this study we sought to determine whether this procedure leads to esophageal motility disturbances and to compare the manometric findings with controls as well as with those seen in children with esophageal atresia and primary anastomosis. Six beagles had esophageal transection and a spiral myotomy, one had esophageal transection without a myotomy, and two served as normal controls. Following esophageal reconstruction, esophageal manometry was studied in all dogs using a standard pull-through technique. We found that the three control dogs all had similar manometric findings with normal peristalsis. In contrast, the dogs with a spiral myotomy all had propagation of waves in the myotomized segment but termination of waves at the anastomotic site. There was delayed velocity through the myotomized segment and retrograde peristalsis distally. Finally, upper esophageal sphincter pressure was elevated, while lower esophageal sphincter pressure was similar to that in the normal dogs. These findings are similar to those described in children with primary anastomosis and suggest that (a) spinal myotomy is a good alternative to other esophageal replacement options in patients with long-gap esophageal atresia and that (b) the motility dysfunction observed in children with esophageal atresia following primary anastomosis may be secondary to the disruption of the vagus nerve and that may be part of the congenital abnormality or secondary to surgical trauma.

Purpose Rectal prolapse is a known postoperative problem in children with anorectal malformations. The aims of this study were to determine the incidence of significant rectal prolapse (>5 mm), to objectively quantify its predisposing factors, and to offer recommendations as to its prevention and surgical treatment. Methods The authors reviewed their series of 1619 patients with anorectal malformations; 1169 underwent primary posterior sagittal anorectoplasty (PSARP) at their institution between 1980 and 2002, and complete records were available for 833. The series was analyzed for incidence of prolapse, type of anorectal malformation, status of the sacrum, muscle quality, associated vertebral and spinal anomalies, and postoperative constipation. A specific technique for prolapse repair was used. Results Of 833 patients, 45 developed significant rectal prolapse (3.8%). The mean age at the time of PSARP was 0.73 years (range, 0.19-5 years). The average time to recognition of prolapse following PSARP was 13.1 months. Of these 45 patients, 32 required surgical repair and of those, 3 required a second surgical repair. The incidence of prolapse varied by complexity of anorectal defect: cloaca (6.2%), rectobladder neck fistula (6.8%), rectourethral fistula (5.4%), rectovestibular fistula (1.2%), rectal atresia (0%), and rectoperineal fistula (0%). There was a significantly increased incidence of prolapse in patients with a low muscle quality score and in patients with vertebral anomalies (20% vs 3.2%). The presence of a tethered cord and an abnormal sacral ratio did not correlate with an increased incidence of prolapse. Twenty-two patients developed prolapse following colostomy closure, and of these, 12 (55%) suffered from constipation. Conclusions The overall incidence of significant rectal prolapse following PSARP is low. Prevention of prolapse with the PSARP technique may be because of key technical steps. Patients with higher anorectal malformations, poorer muscle quality, and vertebral anomalies had a greater risk of developing postoperative rectal prolapse. The presence of tethered cord and quality of the sacrum were not predictive of postoperative prolapse. Constipation seems to be a factor in the development of prolapse.

Background Body heat loss during anaesthesia may result in increased morbidity, particularly in high-risk populations such as children. To avoid hypothermia, a novel thermoregulatory system (Allon) was devised. We tested the safety and efficacy of this system in maintaining normothermia in children undergoing routine surgical procedures. Methods The system consists of a computerized body, which receives continuous afferent data, i.e. core (rectal) temperature. These data are then compared with a preset temperature (37 degrees C) and a microprocessor heating/cooling unit warms/cools the temperature of circulating water in a garment that is specially designed to allow maximal coverage of body surface area, without impingement on the surgical field. Water temperature to the garment was limited to a maximum of 39.5 degrees C. Continuous perioperative monitoring of skin and rectal temperature, heart rate and blood pressure was performed. Postoperative shivering and adverse effects were also assessed. Results The Allon system was used in 38 patients aged 3 months to 14 years undergoing surgery under general anaesthesia lasting more than 30 min. Fifty to 80% body surface area was covered by the garment. Mean operative and postoperative core temperatures were 36.9 +/- 0.5 degrees C and 36.7 +/- 0.5 degrees C, respectively. Intraoperative skin temperatures were maintained at 34.4 +/- 2.7 degrees C. The average core- to-periphery intraoperative gradient was 2.9 +/- 4.9 degrees C. Postoperative shivering was absent in 36 cases and mild in two cases. No device-related adverse effects were observed. Conclusions Perioperative thermoregulation using the Allon system is safe and effective in maintaining body temperature within a narrow range in children undergoing brief surgical procedures.

A role for fibroblast growth factor in liver regeneration has recently been suggested. In this study we followed the intravenous delivery of recombinant human [125I]basic fibroblast growth factor to the liver of rats following 68% partial hepatectomy. The concentration of [125I]basic fibroblast growth factor was higher in the liver (mean +/- SD, 6.8 +/- 0.89% of injected dose) and the kidney (6.7 +/- 0.2%) of sham-operated rats than in the spleen (2.8 +/- 0.45%). It increased threefold in the liver only, soon after 68% partial hepatectomy (20.3 +/- 5.3%, p < 0.001), and remained high for the first 24 h. We also studied the effect of basic fibroblast growth factor injection on the rate of [3H]thymidine incorporation into liver DNA in rats subjected to either 21% or 68% partial hepatectomy. A significant increase was seen after intramesenteric injection of 500 ng basic fibroblast growth factor into rats subjected to 21% partial hepatectomy (23.5 +/- 7.3 cpm/micrograms DNA) compared to saline-injected rats (14.5 +/- 6.4 cpm/micrograms DNA, p = 0.034). A dose of 5000-25,000 ng injected into a peripheral vein resulted in higher thymidine incorporation than in saline-injected control rats (36.9 +/- 12.7 and 9.7 +/- 6.1 cpm/micrograms DNA, respectively; p < 0.0001). No significant effect was seen after 68% partial hepatectomy. Autoradiography showed that the hepatocytes were the predominant labelled cells early after hepatectomy and basic fibroblast growth factor injection. We conclude that basic fibroblast growth factor uptake by the liver is increased after 68% partial hepatectomy and that basic fibroblast growth factor is mitogenic to liver parenchymal cells early after 21% partial hepatectomy.

Hepatocyte transplantation is an emerging approach for the treatment of liver diseases. However, broad clinical application of this method has been limited by restricted source of cells and low efficiency of cell integration within the recipient liver. Heparanase cleaves heparan sulfate proteoglycans in the extracellular matrix and basement membrane, activity that affects cellular invasion associated with cancer metastasis and inflammation. This activity has a multifunctional effect on cell-cell interaction, cell adhesion, and angiogenesis. All these factors are important for successful integration of transplanted hepatocytes. Male donor hepatocytes pretreated with heparanase or untreated were transplanted into recipient female rat spleen following partial hepatectomy. Engraftment efficacy was evaluated by PCR for Y chromosome, histology and PCNA, and heparanase immunohistochemistry. In addition, proliferative activity of hepatocytes in vitro was determined by bromodeoxyuridine immunostaining. The number of heparanase-treated cells detected in the recipient liver was significantly increased three- to fivefold within 24-48 h posttransplantation and twofold at 14 days compared with untreated cells. The transplanted hepatocytes treated with heparanase were clearly seen inside portal vein radicles as cell aggregates up to 72 h posttransplantation. The number of portal radicles filled with heparanase-treated hepatocytes was increased compared to control early after transplantation. Heparanase treatment enhanced hepatocyte and sinusoidal endothelial cell proliferation in the liver, and hepatocyte proliferation within the spleen tissue. Preliminary in vitro studies with isolated hepatocytes treated with heparanase showed increased proliferative activity within 24-48 h of cell culture. These results suggest that preincubation of hepatocytes with heparanase increases the presence of hepatocytes within the recipient liver early following cell transplantation and stimulates both hepatocyte and sinusoidal endothelial cell proliferation.

In beagle dogs, the cervical esophagus was divided 5 cm cranial to the thoracic inlet employing a stapler. The distal esophageal stump was attached to the external surface of the trachea. A spiral myotomy (21/2 revolutions) was made in a 3-cm long segment constituting the distal end of the proximal esophageal segment. This was twisted on a bias with the muscle edges approximated by interrupted stitches to cover the denuded submucosal layer. With moderate traction, this segment could be elongated to a length of 5 cm. A subcutaneous tunnel was created in the anterior chest to accommodate the reconstructed proximal esophageal segment (under slight traction), with its distal end forming a cutaneous esophagostomy. A gastrostomy was created using a Gauderer button (Bard Interventional Products, Billerica, MA) for feeding. After 3 weeks, the proximal esophageal segment was mobilized and removed from the subcutaneous tunnel. The distal esophageal segment was freed from the trachea and 5 to 8 cm of its proximal end was excised. The proximal (myotomized) esophagus was brought down to the stump of the remaining distal esophagus and an anastomosis formed in an end-to-end fashion. Oral feeding was reestablished within 1 week. Prolonged ingestion, observed soon after operation, gradually improved. During a period of 1 to 6 months after the operation, motility of the myotomized segment was tested by barium swallow and manometry. There was neither diverticulum formation nor stenosis. Transit of contrast material in the myotomized segment was smooth and rapid. Manometry demonstrated preservation of motility in the myotomized segment of the esophagus. This technique would appear to have the following advantages in the management of long gap esophageal atresia: (1) preservation of motility in the myotomized esophageal segment by continuity of muscle layers; (2) substantial elongation of the myotomized esophagus; (3) further elongation by continuous traction after creation of the cutaneous esophagostomy; and (4) reduction in the incidence of major anastomotic complications, when compared with the primary combined procedures of concurrent circumferential myotomy and esophageal anastomosis.