Recombinant leptin administration improves early angiogenesis in full-thickness skin flaps: an experimental study.

BACKGROUND: Leptin is a potent direct angiogenic factor that stimulates endothelial cell migration and activation in vitro, and angiogenesis in vivo. In addition, leptin seems to play an important role in angiogenesis as it promotes the formation of new blood vessels. OBJECTIVE: To determine the effect of local application of exogenous leptin on the survival of full thickness skin flaps in an experimental animal model. MATERIALS AND METHODS: Ninety Sprague-Dawley rats were used in this study. A full thickness dorsal flap (10 cm x 2 cm) with the pedicle located at the level of the iliac crest was designed. Animals were divided into ten groups of nine animals each. In the distal two thirds of the flap and by means of subdermal injection at 8 different locations, rats were injected with 100 ng/ml leptin, 250 ng/ml leptin, 500 ng/ml leptin, 1000 ng/ml leptin (groups A, B, C and D), 1 microg/ml VEGF (group E), or 1 ml saline (control group), respectively. For each of the four leptin doses used, another animal group was injected with a combination of leptin/antileptin: 100 ng/ml leptin with 150 ng/ml antileptin, 250 ng/ml leptin with 375 ng/ml antileptin, 500 ng/ml leptin with 750 ng/ml antileptin or 1000 ng/ml leptin with 1500 ng/ml antileptin (groups A1, B1, C1 and D1, respectively), in order to study the inhibition of the leptin factor. Nine rats served as controls and were injected with 1 ml saline solution. Rats were sacrificed 3, 7 and 9 days postoperatively. After sacrifice of the animals, the skin was grossly arranged on its appearance, colour and texture. Full thickness skin flaps were dissected for histological examination. A qualitative analysis of angiogenesis in the flap was conducted following a standard hematoxylin and eosin stain. The wound tissue samples from each experimental group underwent immunohistochemical evaluation of microvessel density by endothelial cell staining with mouse anti-rat CD 34 monoclonal antibody. RESULTS: Immunohistochemical staining revealed that more granulation tissue and improved angiogenesis were observed in group D (1000 ng/ml leptin) flaps compared to those in the VEGF, leptin/antileptin and saline groups. In addition, skin flap survival rate in group D (1000 ng/ml leptin) and group E (1 microg/ml VEGF) were significantly better than those of the other groups. The most impressive formation of new blood vessels was noted in the groups with the higher leptin doses. Surgical wounds in the control, as well as in the leptin/antileptin groups, did not demonstrate any new vessels. CONCLUSION: Exogenous administration of recombinant leptin increases early skin flap angiogenesis in an experimental animal model. Local application of leptin could efficiently improve survival of ischemic skin flaps.

Exogenously-administered leptin increases early incisional wound angiogenesis in an experimental animal model.

BACKGROUND: Leptin is a potent direct angiogenic factor that stimulates endothelial cell migration and activation in vitro, as well as angiogenesis in vivo. In addition, leptin seems to play an important role in clinical angiogenesis by promoting the development of new blood vessels. OBJECTIVE: To determine the effect of exogenously administered leptin on incisional wound healing in an experimental animal model. MATERIALS AND METHODS: Sixty-three Sprague-Dawley male mice were used for the study. Full thickness incisional wound was considered as the wound model. The mice were divided into seven groups of nine animals each. Surgical wounds were injected with murine recombinant leptin. Three different leptin doses of 100 pg/ml, 200 pg/ml and 500 pg/ml were used in different animal groups (A, B and C). For each of the three leptin doses used, another animal group was evaluated with a combined injection of leptin and antileptin: 100 pg/ml leptin with 50 pg antileptin, 200 pg/ml leptin with 100 pg antileptin, 500 pg/ml leptin with 250 pg antileptin (A1, B1, and C1), in order to study the inhibitory effect on the leptin factor. Nine mice served as controls. These were injected with 0.3 ml water for injection solution. Mice were sacrificed 3, 7 and 9 days postoperatively. After sacrifice of the animals, the skin was grossly assessed for appearance, colour and texture. Full thickness incisional wounds were dissected for histological examination. A qualitative analysis of angiogenesis in the surgical wound was conducted following a standard hematoxylin and eosin stain. The wound tissue samples from each experimental group underwent immunohistochemical evaluation of microvessel density by endothelial cell staining with mouse anti-rat CD34 monoclonal antibody. RESULTS: The most impressive growth of new blood vessels appeared seven and nine days after treatment with the highest leptin doses. There were no significant differences in microvessel density at seven or nine postoperative days among different groups treated with leptin. None of the wounds from the control group, or those from animal groups treated with the combined injection of leptin and antileptin developed any new vessels. CONCLUSION: Exogenous administration of leptin may increase early tissue angiogenesis in the incisional wound of an experimental animal model.

Subcutaneous metastasis from a gastrointestinal stromal tumor of the stomach: a case report.

Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms of the stomach, which account for approximately 3.6% of all gastric tumors. They may or may not be malignant. Malignant GIST rarely metastasizes to distant organs. We report a case of a gastric GIST diagnosed in a 69- year-old woman presented with a synchronous subcutaneous paraumbilical metastasis. Computed tomography (CT) scan demonstrated a space-occupying lesion arising from the gastric wall with a second well-circumscribed lesion in the subcutaneous tissue which infiltrated the aponeurosis of the right rectus abdominis. The patient underwent total gastrectomy and resection of the subcutaneous mass. Pathologic examination of the gastric tumor and subcutaneous mass showed histological and immunohistochemical characteristics of a GIST. The patient succumbed on the 4th postoperative day. Gastric stromal tumor metastasis must be taken into consideration in the differential diagnosis of a palpable paraumbilical mass in a patient diagnosed with malignant GIST.

Laparoscopic cholecystectomy in a patient with previous open cholecystostomy.

We report the case of a successful elective interval laparoscopic cholecystectomy in a patient with a previous tube cholecystostomy that had been performed surgically 8 weeks earlier for an attack of acute calculous cholecystitis. At surgery, the major omentum was adherent to the right lateral abdominal wall, completely covering the liver edge, the gallbladder, and the inserted tube. The gallbladder and the tube within it were dissected free from the abdominal wall and the greater omentum, the cholecystostomy tube was removed, and the operation was completed successfully without any further difficulties.

Penetration of clarithromycin in experimental pleural empyema model fluid.

BACKGROUND: The degree of penetration of clarithromycin into the pleural fluid has not been studied. OBJECTIVE: To determine the degree to which clarithromycin penetrates into empyemic pleural fluid using a new rabbit model of empyema. METHODS: An empyema was created via the intrapleural injection of 1 ml turpentine followed 24 h later by instillation of 5 ml (10(10)) Escherichia coli bacteria (ATCC 35218) into the pleural space of New Zealand white rabbits. After an empyema was verified by thoracentesis and pleural fluid analysis, clarithromycin 30 mg/kg was administered intravenously. Antibiotic levels were determined on samples of pleural fluid and blood samples collected serially over 12 h. Antibiotic levels were estimated using HPLC. RESULTS: The antibiotic penetrated well into the empyemic pleural fluid (AUC(PF)/AUC(serum) ratio of 1.57). The time to equilibration between the pleural fluid and blood antibiotic levels was 8 h. The peak pleural fluid level (Cmax(PF) of 2.88 microg/ml) occurred 1 h (Tmax(PF) of 1 h) after infusion and decreased thereafter. The Cmax(serum) was 3.53 microg/ml at 1 h after administration. CONCLUSION: The levels of clarithromycin in the pleural fluid after intravenous administration are inhibitory for most of the usual pathogens causing empyema. The degree of penetration of clarithromycin should be considered when macrolides are selected for the treatment of patients with empyema.