The role of peroxisome proliferator-activated receptor-beta/delta in epidermal growth factor-induced HaCaT cell proliferation.

Epidermal growth factor (EGF) has been shown to be a potent mitogen for epidermal cells both in vitro and in vivo, thus contributing to the development of an organism. It has recently become clear that peroxisome proliferator-activated receptor-beta/delta (PPARbeta/delta) expression and activation is involved in the cell proliferation. However, little is known about the role of PPARbeta/delta in EGF-induced proliferation of HaCaT keratinocytes. In this study, HaCaT cells were cultured in the presence and absence of EGF and we identified that EGF induced an increase of PPARbeta/delta mRNA and protein level expression in time-dependent and dose-dependent manner, and AG1487, an EGF receptor (EGFR) special inhibitor, caused attenuation of PPARbeta/delta protein expression. Electrophoretic mobility shift assay (EMSA) revealed that EGF significantly increased PPARbeta/delta binding activity in HaCaT keratinocytes. Antisense phosphorothioate oligonucleotides (asODNs) against PPARbeta/delta caused selectively inhibition of PPARbeta/delta protein content induced by EGF and significantly attenuated EGF-mediated cell proliferation. Treatment of the cells with L165041, a specific synthetic ligand for PPARbeta/delta, significantly enhanced EGF-mediated cell proliferation. Finally, c-Jun ablation inhibited PPARbeta/delta up-regulation induced by EGF, and chromatin immunoprecipitation (ChIP) showed that c-Jun bound to the PPARbeta/delta promoter and the binding increased in EGF-stimulated cells. These results demonstrate that EGF induces PPARbeta/delta expression in a c-Jun-dependent manner and PPARbeta/delta plays a vital role in EGF-stimulated proliferation of HaCaT cells.

Reconstruction of fingers after electrical injury using lateral tarsal artery flap.

OBJECTIVE: Electrical injuries to the fingers account for the majority of total severe burns that occur each year. While several types of flaps have been used in covering finger defects, all have limitations or disadvantages. The purpose of this study was to introduce our clinical experiences of using the lateral tarsal artery (LTA) flap to successfully restore fingers after electrical injury. PATIENTS AND METHODS: From 2005 to 2012, 10 patients with 14 severe electrical burns to their fingers, including six thumbs and four index and four middle fingers, were treated with LTA flap. The wound size ranged from 2.0×3.0 cm to 3.5×5.0 cm. The flap with free tendon graft was used to repair the tendon defect in four cases, free nerve graft was used to repair the feeling defect in two cases, and the flap with nerve was used to repair the feeling defect in two cases. All the patients were followed up for 3 months to 2 years. RESULTS: All skin flaps adhered successfully and there were no complications. All patients were satisfied with the esthetic appearance and functional outcome of the finger reconstruction. CONCLUSION: LTA flap is a reliable method to restore fingers after severe electrical injuries.

[Repair of wound on hand or foot due to electrical burn using free lateral upper arm perforator flap].

OBJECTIVE: To observe the effect of free lateral upper arm perforator flap in repairing wound on hand or foot due to electrical burn. METHODS: Six patients with full-thickness wounds on hand or foot resulting from electrical burn were hospitalized from June 2010 to June 2013. The wounds ranged from 6.0 cm ×4.0 cm to 8.5 cm×7.5 cm in area. Free lateral upper arm perforator flaps were used to repair these defects, with flap area ranging from 9 cm ×4 cm to 12 cm × 9 cm. The donor sites in five cases were closed by suturing; the other one donor site was closed by transplantation of full-thickness skin from abdomen. RESULTS: One flap used to repair the wound in middle finger failed due to failure of venous return, and it was repaired with full-thickness skin harvested from abdomen after dressing change. The other five flaps survived resulting in good elasticity and matched appearance of the recipient area without obvious bulkiness. Patients were followed up for 6 to 24 months. The function of the injured hands or feet recovered well, and the results of function evaluation of five hands were excellent in 2 cases, good in 2 cases, and poor in 1 case. Little scar formation with no contraction or function impairment was observed on donor site, and the result was satisfactory. CONCLUSIONS: Free lateral upper arm perforator flap, with long vessel and less adipose tissue, is suitable for repairing small but deep wound on hand or foot due to electrical burn.

MicroRNA profiling in denatured dermis of deep burn patients.

BACKGROUND: Denatured dermis is a part of the dermis in deep burn wound and has the ability to restore normal morphology and function. Skin grafting with the preservation of denatured dermis is a new kind of surgical procedure and has reported satisfactory clinical effects, such as lessened scar contracture and a better restoration of the appearance and function. However, the underlying mechanism of the recovery of denatured dermal function remains unclear. MicroRNAs (miRNAs) are a new class of regulatory noncoding single-stranded RNAs, which play a key role in normal development and physiology, as well as in disease development. This study analysed the profile of miRNAs in denatured dermis from patients and further investigated the possible roles of miRNAs played in the functional recovery of denatured dermis by prediction of the potential target genes of differentially expressed miRNAs. METHODS: The denatured dermis and paired normal skin were collected and analysed by miRNA array. The miRNA profiling results were validated by real-time reverse transcriptase polymerase chain reaction (RT-PCR), and bioinformatics' analysis was employed to further predict the miRNA targets. RESULTS: A total of 66 miRNAs were differentially expressed in denatured dermis compared with those in normal skin, among which 34 were down-regulated while 32 are up-regulated. The most significantly up-regulated miRNA was miR-663, and the most significantly down-regulated one was miR-203. Differentially expressed miRNAs were predicted to be related with several signalling pathways in wound healing. CONCLUSION: The differential miRNA expression identified in this study supplies experimental basis for further understanding the mechanisms of functional recovery of the denatured dermis.

[Repair of large defects in upper extremities with pedicled combined flap].

OBJECTIVE: To explore the flap transposition for repairing large defects in upper extremities. METHODS: 12 cases with large defects in elbow, forearm, wrist or palm caused by high-voltage electricity, hot-pressure or crush, were treated. 4 cases were treated with latissimus dorsal myocutaneous flaps combined iliolumbar flaps. 2 cases were treated with latissimus dorsal myocutaneous flaps combined lateral thoracic flaps. 6 cases were treated with large combined thoracic-abdomen flaps. RESULTS: All the flaps survived except for one flap with 2 cm distal necrosis and sub-flap infection. Satisfactory results were achieved. CONCLUSIONS: Early debridement and reconstruction with pedicled combined flaps are feasible and reliable for large defects in the upper extremities.

[Repair of high-voltage electrical burn in the neck].

OBJECTIVE: To explore methods of repair of high-voltage electrical burn in the neck. METHODS: Thirty-seven patients with high-voltage electrical burn in neck hospitalized since 1985 were enrolled in this study. After debridement, the wounds were repaired with latissimus dorsi myocutaneous flap, trapezius myocutaneous flap, platysma myocutaneous flaps, pectoralis major myocutaneous flap, or latissimus dorsi myocutaneous flap combined with pectoralis major myocutaneous flap. RESULTS: Necrosis occurred at edge of flap (about 1 - 2 cm in breadth) in 3 patients, and the other flaps survived well with perfect appearance and local function. CONCLUSION: To repair with pedicled myocutaneous flaps and combined flaps after early debridement can be safe, effective and reliable in the management of patients with high-voltage electrical burn in the neck.

[Application of bridged free latissimus dorsi musculo-cutaneous flap on the soft tissue defects in lower extremities].

OBJECTIVE: To evaluate the effect of bridged free latissimus dorsi musculo-cutaneous flap on repairing of soft tissue defect in the lower extremity. METHODS: Seven patients with extensive soft tissue defects in the lower extremities were enrolled in the clinical investigation. The defects were all repaired with bridged free latissimus dorsi musculo-cutaneous flaps. The condition of the blood vessels in the flaps and the healthy extremities was examined with ultrasound Doppler before the operation to assure the blood circulation of grafted flap. After debridement, the flap was designed in accordance with the size and the depth of the wound. Then the transplantation of the flaps were done. The operative indication and points for attention were summarized thereafter. RESULTS: All the 7 flaps survived. All patients recovered well with satisfactory function and external appearance, except flap reduction was done in 2 patients due to undue thickness of the flaps. Indications for operation: (1) Patients with anterior or posterior tibial artery injury in the injured lower extremity in which arterial transplantation was not possible to allow the free transplantation of a skin flap. (2) The injury was extensive and deep, with the injurious condition of the blood vessels indeterminable and no healthy artery could be found for anastomosis with a donor artery. (3) No vascular injury could be identified in the contralateral healthy extremity. Points for attention included that the blood supply of the flap to be transferred should be adequate, and the survival of the flap after division of the pedicle should be assured. The length of the flap to be transferred should be longer by 10% than the distance between the site of transplantation in the lower extremities and the donor area; and the donor area should be larger by 20% than the recipient area. The skin area of the flap to be transferred should be broad enough avoid tension so that there would be no pressure on the blood vessels. Pay attention to the blood supply of the flap after operation, and the recipient limb should be properly immobilized. CONCLUSION: The repair of extensive soft tissue defect in the lower extremity with bridged free latissimus dorsi musculo-cutaneous flap could be satisfactory. Proper wound management, broad flap, stable immobilization were the pivotal points for the success of the operation.

[The use of composite sodium lactate and sorbitol composition in fluid resuscitation for shock in patients with major burn].

OBJECTIVE: To investigate the feasibility of the use of sodium lactate and sorbitol (CISS) in the fluid resuscitation for shock in patients with major burns. METHODS: Fifty - three adult patients with major burns (hospitalized within 6 hours after burns) were randomly divided into A (n = 24, with i.v. infusion of 50 g/L CISS, 2 000 ml per day) and B (n = 29, with i. v. infusion of 50 g/L glucose, 2 000 ml per day) groups. The amount of electrolytes and colloid as the main resuscitation fluids was calculated according to the formula in both groups. Meanwhile, additional electrolytes and insulin were supplemented to the patients in the B group. The result of combating shock, energy supply, and side effects in the two groups were observed. The changes in hepatic and renal function, and the changes in electrolytes were monitored. The amount of fluid supplementation and urinary volume were recorded. The level of blood glucose of each patient was determined at the admission time and 24, 48, and 72 hours after injury. RESULTS: No obvious difference was found in control of shock and energy supply between A and B group. There was no side effects or damage to hepatic and renal function related to infused fluids in A group. But the patients of the B group required supplementation of exra electrolytes and insulin during the fluid resuscitation period in order to maintain the normal levels of electrolytes and blood glucose, and this was not necessary in group A. The diuretic effect in group A was better than that in group B (average urinary volume in the first two 24 hours: group A: 1.9 +/- 0.6 and 3.3 +/- 0.8 L; group B:1.0 +/- 0.5 and 2.3 +/- 0.8 L). CONCLUSION: The use of CISS during shock stage of the patients with major burns could be beneficial to the replenishment of blood volume, control of shock, promotion of diuresis and subsidence of edema. It could also provide electrolytes and energy, without the influence on the level of blood glucose.

[The repair of bulky tissue defect of forearm with skin flaps].

OBJECTIVE: To evaluate the repairing methods of bulky tissue defect of forearm with flaps. METHODS: Twenty-one burned patients with wounds in the forearm were enrolled in this study. The injury causes were high-voltage electricity, hot press or crush injury. After local debridement, the forearm defects were repaired with pedicled complex flaps, latissimus dorsi musculocutaneous island flaps or large thoraco-abdominal flaps immediately. RESULTS: All the flaps survived very well with satisfactory results except for 1 patient in whom local ischemic necrosis and sub-flap infection at the distal end of the flap occurred. CONCLUSION: Early debridement followed by skin flaps with pedicles or musculocutaneous flaps transfer could be simple, safe and reliable treatment strategies in the management of bulky tissue defects of the forearm due to burn, electric injury, or other devastating injuries.

[Clinical analysis of brain injury in patients injured by high voltage electricity].

OBJECTIVE: To explore the pathogenic characteristics and management of brain injury in patients injured by high voltage electricity. METHODS: One hundred and thirty eight patients injured by electricity were enrolled in this study. Postburn brain injury was diagnosed by clinical sighs and imaging analysis. The brain injury was graded as mild, moderate, severe and most severe. The relationships among the inlet of the electric current and the electric voltage and the degree of brain injury were analyzed, and the causes and pathogenesis of the brain injury were suggested. Treatment modality was optimized for the patients according to the diagnostic data. RESULTS: In this group of patients, brain injury was identified in 106 cases, mostly rated as mild and moderate. Only 4 cases were ranked as severe degree with positive imaging findings. The electric voltage seemed to be not correlated with the incidence of postburn brain injury. But the intensity of electric current and the locations of electrical current inlet and outlet were closely related to the degree of brain injury. Among all the patients in this group, 131 survived and 7 died after treatment. But there was no death due directly to brain injury. CONCLUSION: There was high incidence of postburn brain injury in patients injured by high voltage electricity. The injury might be related to the direct effect of electrical current on the brain tissue, to mechanical injury, to the cardio-pulmonary lesions caused by electrical current, or to massive skin burn. Early and accurate diagnosis of the injury was of key importance for lowering both mortality and disability.