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Dermal scarring from motor vehicle accidents, severe burns, military blasts, etc. is a major problem affecting over 80 million people worldwide annually, many of whom suffer from debilitating hypertrophic scar contractures. These stiff, shrunken scars limit mobility, impact quality of life, and cost millions of dollars each year in surgical treatment and physical therapy. Current tissue engineered scaffolds have mechanical properties akin to unwounded skin, but these collagen-based scaffolds rapidly degrade over 2 months, premature to dampen contracture occurring 6-12 months after injury. This study demonstrates a tissue engineered scaffold can be manufactured from a slow-degrading viscoelastic copolymer, poly(ι-lactide-co-ε-caprolactone), with physical and mechanical characteristics to promote tissue ingrowth and support skin-grafts. Copolymers were synthesized via ring-opening polymerization. Solvent casting/particulate leaching was used to manufacture 3D porous scaffolds by mixing copolymers with particles in an organic solvent followed by casting into molds and subsequent particle leaching with water. Scaffolds characterized through SEM, micro-CT, and tensile testing confirmed the required thickness, pore size, porosity, modulus, and strength for promoting skin-graft bioincorporation and dampening fibrosis in vivo. Scaffolds were Oxygen Plasma Treatment and collagen coated to encourage cellular proliferation. Porosity ranging from 70% to 90% was investigated in a subcutaneous murine model and found to have no clinical effect on tissue ingrowth. A swine full-thickness skin wound model confirmed through histology and Computer Planimetry that scaffolds promote skin-graft survival, with or without collagen coating, with equal safety and efficacy as a commercially available tissue engineered scaffold. This study validates a scalable method to create poly(ι-lactide-co-ε-caprolactone) scaffolds with appropriate characteristics and confirms in mouse and swine wound models that the scaffolds are safe and effective at supporting skin-grafts. The results of this study have brought us closer towards developing an alternative technology that supports skin grafts with the potential to investigate long-term hypertrophic scar contractures.

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BACKGROUND: The success of surgical flaps is improved by timely correction of vascular compromise. Current monitoring methods are labor or cost intensive or have limited clinical benefit. We hypothesize that injectable oxygen sensors can identify acute vascular compromise. The purpose of this study was to use a long-term, real-time method of tissue oxygenation detection in a rat flap model with vascular manipulation. METHODS: Sensors incorporated benzo-porphyrin dye into a microporous hydrogel and were injected intradermally 1 day before flap elevation. Inspired oxygen was modulated between 100% and 12% to confirm sensor O2 sensitivity. Eight random flaps (4 cm wide, 8 cm long) were elevated. Sensor and clinical observation to temporary clamping of the flap vascular pedicle was recorded. Sodium fluorescein in saline was injected intraperitoneally on postoperative days 0, 3, and 7 with subsequent perfusion area analysis. RESULTS: Tissue oxygen tension measurements reflected the changes in inspired oxygen levels. Clinical observation of the flaps did not show any significant change in color or temperature with pedicle clamping. However, clamping of the pedicle resulted in a significant decrease in sensor tissue oxygen tension within 70 seconds. CONCLUSION: Oxygen monitoring of myocutaneous flaps is sensitive and can detect acute vascular occlusion. This technique is faster than current methods and offers a cost-effective and accurate means of monitoring surgical tissues.

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INTRODUCTION: Cancer remains a major cause of death in children, but recent advances in supportive care and progress in the use of chemotherapy have considerably improved the prognosis. The need for intensive care management in pediatric oncology patients is increasing. However, studies demonstrating their outcome in the literature are still deficient, especially in developing countries. Here, we aim to report our experience in managing patients admitted to the pediatric intensive care unit (PICU) at South Egypt Cancer Institute, a tertiary university oncology center in a developing country. PATIENTS AND METHODS: A review of all cancer patients admitted to the PICU at South Egypt Cancer Institute between January 2007 and December 2011 and an evaluation of prognostic factors that may correlate to their short-term outcome were performed. RESULTS: A total of 550 pediatric oncology patients were admitted to the PICU on 757 occasions. Hematological malignancies represented 73.6% of the cases. The median duration of PICU stay was 5 days. Sepsis and respiratory failure were the most frequent indications for PICU admission. The overall survival at the time of discharge from the PICU was 60%. Several factors were found to significantly affect the outcome of patients admitted to the PICU, including the underlying disease, the reason for admission, the intervention used, and the number of failing organs at the time of admission to the PICU. CONCLUSIONS: The prognosis of patients admitted to the PICU in developing countries is still behind those in developed ones. Late referral, especially of patients presenting with respiratory failure, sepsis, and multiorgan failure usually, requires urgent intervention with inotropic support, oxygen therapy, and mechanical ventilation and is significantly associated with poor outcomes, especially in patients with hematological malignancies.

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Objective. Several studies showed better outcome in adolescents and young adults with acute lymphoblastic leukemia (ALL) treated with pediatrics protocols than similarly aged patients treated with adults protocols, while other studies showed similar outcome of both protocols. We conducted this study to compare the outcome of our pediatrics and adults therapeutic protocols in treatment of adolescents ALL. Patients and Methods. We retrospectively reviewed files of 86 consecutive adolescent ALL patients aged 15-18 years who attended to outpatients clinic from January 2003 to January 2010. 32 out of 86 were treated with pediatrics adopted BFM 90 high risk protocol while 54 were treated with adults adopted BFM protocol. We analyzed the effect of different treatment protocols on achieving complete remission (CR), disease-free survival (DFS), and overall survival (OS). Results. The 2 patients groups have almost similar characteristics. The CR was significantly higher in pediatrics protocol 96% versus 89% (P = 0.001). Despite the fact that the toxicity profiles were higher in pediatrics protocol, they were tolerable. Moreover, the pediatrics protocol resulted in superior outcome in EFS 67% versus 39% (P = 0.001), DFS 65% versus 41% (P = 0.000), and OS 67% versus 45% (P = 0.000). Conclusion. Our study's findings recommend using intensified pediatrics inspired protocol to treat adolescents with acute lymphoblastic leukemia.