Efficacy of dermal scaffold for promoting repair of acute full-thickness skin defects in pigs / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the efficacy of Lando dermal scaffold for promoting repair of acute full-thickness skin defects in pigs and explore the possible mechanism.</p><p><b>METHODS</b>Three 5 cm×5 cm full-thickness skin defects were created on the left dorsal skin (control group) and another 3 on the right dorsal skin (treatment group) of each of 6 Tibetan pigs. The wounds in the treatment group were covered with a bilayer artificial skin (Lando) and the control wounds with vaseline gauze. In both groups, autogenous split-thickness skin were grafted to the wounds 2 weeks later (with the silicone rubber membrane removed before grafting in the treatment group). At 3 days and 2 and 10 weeks after the injury, the wounds were assessed for general condition and contraction, and tissue samples were collected from the wounds to examine the expressions of α-smooth muscle actin (α-SMA) and transforming growth factor-β1 (TGF-β1) using immunohistochemistry and the expressions of MMP-1 and TIMP-1 mRNA using RT-PCR.</p><p><b>RESULTS</b>At 3 days after the injury, the wounds in the 2 groups showed no significant differences in the results of any examinations. At 2 weeks after the injury, the wounds in the treatment group showed rich and more smooth granulation tissues with more regular wound edges compared with the control wounds. At 2 and 10 weeks after the injury, the wound contraction rates in the treatment group were (30.5∓3.4)% and (39.2∓2.8)%, respectively, significantly lower than the rates of (51.8∓2.6)% (t=-29.840, P=0.000) and (60.7∓2.2)% (t=-50.213, P=0.000) in the control group. At 2 weeks, the wound tissues in the treatment group expressed significantly higher levels of α-SMA (t=15.921, P=0.000) and TGF-β1 (t=29.995, P=0.000) than the control wounds, but at 10 weeks, the expressions of α-SMA (t=-41.823, P=0.000) and TGF-β1 (t=-99.777, P=0.000) in the treatment group were significantly lower than those in the control group. Compared with those in the control group, the expression of MMP-1 mRNA in the treatment group was significantly lower at 2 weeks (t=-45.412, P=0.000) but significantly higher at 10 weeks (t=78.769, P=0.000), and the expression of TIMP-1 mRNA in the treatment group was significantly lower both at 2 weeks (t=-27.064, P=0.000) and at 10 weeks (t=-40.535, P=0.000).</p><p><b>CONCLUSIONS</b>Lando dermal scaffold can promote granulation tissue growth possibly in relation with increased TGF-β1 and decreased MMP-1 expression in the wounds. This scaffold material also reduces wound contraction and lessens scar hyperplasia and contracture after wound healing, probably as a result of decreased α-SMA, TGF-β1, and TIMP-1 and increased MMP-1 expressions.</p>

Effects of vacuum drainage combined with heparin irrigation for treatment of scald burns with seawater immersion in rabbits / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of closed vacuum drainage combined with heparin irrigation in the treatment of scald burns with seawater immersion in rabbits.</p><p><b>METHODS</b>Twenty New Zealand rabbits were subjected to deep partial-thickness scald burns in 4 regions on the bilateral skin of the spine. The wounds were managed with common dressing (group A), common dressing after seawater immersion (group B), closed vacuum drainage after seawater immersion (group C), or closed vacuum drainage combined with heparin irrigation after seawater immersion (group D). Wound effusion and tissue necrosis were observed at 1, 3, 5 and 7 days after the burns. Tissue samples were collected from the wounds for HE staining and immunohistochemistry for VEGF and CD31, and the changes of capillary endothelial cells in the wound were observed using electron microscopy. The water content in the wound tissues was determined, and the wound healing rate was calculated after the injury.</p><p><b>RESULTS</b>Sea water immersion of the wound results in earlier onset of edema and more extensive tissue necrosis in the scalded rabbits. The mean necrotic area in groups C and D was smaller than that in group B early after the burns, and vacuum drainage promoted necrotic tissue elimination and accelerated wound healing. Early after the burns, water content in the tissues increased with time in all the groups and reached the highest level at 3 days, and was significantly lower in groups C and D than in group B. Pathologically, vascular endothelial cell damage at the wound site was worsened after seawater immersion. In group D, the basement membrane damage was milder and the endothelial cell membrane remained intact at the wound site, where new blood vessels occurred at 3 days after the burns, a time earlier than that in the other 3 groups with also the highest vascular density.</p><p><b>CONCLUSIONS</b>Closed vacuum drainage combined with heparin irrigation can relieve edema at the scald wound with seawater immersion, improve microcirculation, accelerate the removal of necrotic tissue, and promote the growth of new blood vessels.</p>

Expression of vascular endothelial growth factor in deep second-degree scald wounds in rats / 中国医学科学院学报

<p><b>OBJECTIVE</b>To observe the expression of vascular endothelial growth factor(VEGF)in deep second-degree scald wounds,with an attempt to further explore the role of VEGF in burn wound healing.</p><p><b>METHODS</b>Totally 36 adult Wistar rats were randomized into two groups: the scald group(30 rats)and the control group(6 rats). In the scald group,rat models of deep second-degree scald wounds were established. Full-thickness tissues of the wounds were collected respectively 1,3,7,14,and 21 days after the modeling. The expressions of the VEGF mRNA and protein were detected with real-time quantitative PCR and Western blot,respectively. In the control group,the same procedures were performed but without modeling.</p><p><b>RESULTS</b>Compared with the control group,the expressions of VEGF mRNA and proteins were significantly higher in the scald group(P<0.05). The expression levels reached the peak on day 1,gradually decreased on day 3,reached the lowest points on day 14,but increased again on day 21.</p><p><b>CONCLUSIONS</b>VEGF is involved in the healing of scald burns. The expression of VEGF during the wound healing is closely correlated with the wound angiogenesis.</p>

Clinical observation on repairing of wounds of skin graft donor site with acellular tissue engineering dermal matrix / 中华烧伤杂志

<p><b>OBJECTIVE</b>To evaluate the clinical efficacy of acellular tissue engineering dermal matrix (ATDM) in repairing wounds of skin graft donor site.</p><p><b>METHODS</b>Sixty patients with burn or chronic wounds hospitalized from January 2011 to April 2012 received autologous skin grafting. One wound [with size larger than 55 cm(2), and thickness of (0.33 ± 0.03) mm] out of multiple skin graft donor sites of every patient was selected, and it was divided into two parts in accordance with self-control principle. A part of wound close to the wound edge with diameter of 5 cm was taken as trial area (treated with ATDM), and the remaining wound was taken as control area (treated with vaseline gauze) according to the random number table. Blood and urine routine, liver and kidney function, and levels of IgG and IgM in blood of patients were measured one day before operation and on the 1st day after wound healing. Vital signs of patients were recorded on the operation day and the wound healing day. Gross condition of the wounds was observed during dressing change. Wound healing time was recorded. The healed wound was observed histologically. Data were processed with Log rank test or t test.</p><p><b>RESULTS</b>Leucocyte count was lowered on the 1st day after wound healing [(7.1 ± 1.2)×10(9)/L] as compared with that one day before operation [(10.1 ± 1.5)×10(9)/L, t = -12.10, P < 0.01]. The differences were not statistically significant in red blood cell count, haemoglobin level, platelet count, urine routine, levels of indexes of liver and kidney function, levels of IgG and IgM in blood between one day before operation and the 1st day after wound healing, or in vital signs (including body temperature, pulse, respiration, systolic pressure, and diastolic pressure) between the operation day and the wound healing day (with t values from -1.43 to 1.88, P values all above 0.05). No adverse effects such as abnormal exudation, itching, redness and swelling, and exanthema were observed in the wound. The median wound healing time in trial area was 12 d (95% confidence interval: 11 - 13 d), which was significantly shorter than that in control area [17 d (95% confidence interval: 16 - 18 d), χ(2) = 24.9, P < 0.01]. The healed wound of trial area was closer to the normal skin than that of control area in the shape and distribution of Fb and vascular endothelial cell, and the shape of the basilar membrane and the epidermal layer.</p><p><b>CONCLUSIONS</b>ATDM can accelerate healing of wound of skin graft donor site, and no adverse reactions were observed.</p>

Expression of aquaporin-1 in myocardium of rats in the early stage after scald and its relationship with myocardial edema / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the changes in aquaporin-1 (AQP-1) expression in myocardium of scalded rats in early stage of a burn injury, and to analyze its relationship with myocardial edema.</p><p><b>METHODS</b>Thirty-six healthy Wistar rats were divided into normal control (n = 6, without scald) and scald (n = 30) groups according to the random number table. Rats in scald group were inflicted with 30%TBSA full-thickness scald on the back, and intraperitoneally injected with Ringer's solution for antishock treatment. Myocardium tissue from left ventricle and serum specimen in rats of scald group were collected at post scald hours (PSH) 2, 8, 12, 24, and 48 (with 6 rats at each time point). Myocardial water ratio was determined by dry-wet weight method. The distribution of AQP-1 protein in myocardium was observed with immunohistochemical staining. The expression of myocardial AQP-1 mRNA was assessed with quantitative real-time PCR. The serum content of cardiac troponin-I (cTnI) was determined with ELISA. The rats in normal control group were detected with above-mentioned method. Data were processed with one way analysis of variance and LSD test. Correlation analysis was performed between AQP-1 mRNA and myocardial water ratio, AQP-1 mRNA and the serum content of cTnI in scald group at each time point.</p><p><b>RESULTS</b>Compared with that in normal control group, the myocardial water ratio in scald group was markedly increased during PSH 8-48 (P values all below 0.01), and it peaked at PSH 12 [(80.79 ± 0.12)%]. In both groups, AQP-1 was mainly expressed in endothelial cells of capillaries and pericellular membrane of myocardial cells. The expression of AQP-1 in scald group was markedly increased from PSH 2 to PSH 48. The expression of myocardial AQP-1 mRNA in scald group was markedly higher from PSH 2 to PSH 48 than that in normal control group (P values all below 0.01), and it peaked at PSH 12 [(6.2 ± 0.7)%]. The serum content of cTnI in scald group was obviously higher from PSH 2 to PSH 48 than that in normal control group (P values all below 0.01), and it peaked at PSH 12 [(5.83 ± 0.51) µg/L]. There were statistically positive correlations between AQP-1 mRNA expression and myocardial water ratio (r = 0.849, P < 0.01), AQP-1 mRNA expression and the serum content of cTnI (r = 0.973, P < 0.01) in scald group.</p><p><b>CONCLUSIONS</b>AQP-1 may play a key role in the development of myocardial edema in rats with scald.</p>

Treatment of a patient with massive unhealed wound accompanied by wound sepsis in late stage after burn injury / 中华烧伤杂志

This article analyzed the medical records of a patient with 90% TBSA unhealed wound accompanied with wound sepsis 50 days post burn (PBD) and to discuss the ideal strategies of treatment for such patients in such condition. This was a 24-year-old male patient suffering from flame burn with 95% TBSA wound and severe inhalation injury. Meek skin grafting with autologous scalp was performed once to the thoracic and abdominal regions; intermingled skin grafting of autologous scalp microskin and large sheet of allograft was performed twice to the limbs within PBD 31. The patient was transferred to our hospital on PBD 50 with 90% TBSA wound unhealed, leaving a vast amount of necrotic tissue and allografts. Furthermore, he was complicated by sepsis, pulmonary infection, and gastric ulcer. Debridement and allogenic skin grafting were performed on the first day after hospitalization. When the condition of wounds was improved, transplantation of a large sheet of allogenic skin with inlaid small pieces of autologous skin, intermingled skin grafting of autologous and allogenic skin, and small pieces of autologous skin grafting were performed. Because of the shortage of donor area, the exposed wounds were temporarily covered with allogeneic skin. Epidermal growth factor was used to promote the healing of autologous skin donor site and deep partial-thickness burn wound. Autologous skin grafting was performed whenever source of healthy skin was available. Systemic use of effective antibiotics, nutritional support and therapy, and other comprehensive measures also contributed to the success of treatment of this patient suffering from wound sepsis. The patient was cured and discharged on PBD 145.

Effects of exendin-4 on rat cardiomyocyte apoptosis early after severe scald injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effect of exendin-4 on cardiomyocyte apoptosis in the early stage after scald injury in rats and explore the mechanisms.</p><p><b>METHODS</b>Fifty-four healthy adult SD rats were randomly divided into normal control group (n=6), scald group (n=24) and scald with exendin-4 treatment group (n=24). In the latter two groups, the rats were subjected to 30% TBSA full-thickness scald burns on the back, and Parkland formula was used for determining the resuscitation fluid volume. In exendin-4 treatment group, the rats received intraperitoneal injection of 5 µg/kg exendin-4 after the scald. Apoptosis of the cardiomyocytes from the left ventricle was determined by TUNEL assay and the activity of caspase-3 in the myocardium was assessed.</p><p><b>RESULTS</b>In the scald group, the apoptotic index of the cardiomyocytes was increased at 6 h post-burn, reaching the peak level at 12 h, and maintained a significantly higher level than that in the normal control at 48 h (P<0.05). Myocardial caspase-3 activity in the scald group was increased at 6 h post-burn and reached the peak at 12 h, still maintaining a high levels at 24 h (P<0.05). In exendin-4 treatment group, the apoptotic index of the cardiomyocytes was significantly lower than that in the scald group at 6, 12, 24 and 48 h post-burn (P<0.05), and so was the caspase-3 activity at 6, 12 and 48 h (P<0.05). A significant positive correlation was found between the apoptotic index of the cardiomyocytes and myocardial caspase-3 activity in the rats (P<0.05).</p><p><b>CONCLUSION</b>Exdendin-4 can inhibit rat cardiomyocyte apoptosis early after scald injury possibly by suppressing caspase-3 activity in the myocardium.</p>

Changes of aquaporin-1 expression in rat myocardium after severe burn / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in the myocardial expression of aquaporin-1 (AQP1) protein and its association with myocardial edema in rats with severe burns.</p><p><b>METHODS</b>Forty-eight healthy adult Wistar rats were randomly divided into normal control group (n=6) and burn injury group with third degree burn of 30% total body surface area, and the latter group was further divided into 2, 4, 8, 12, 24, 48 and 72 h groups. The changes of myocardial water content were investigated by dry-wet weight methods. Enzyme-linked immunosorbent assay was used to detect the changes in AQP1 expression at different time points after sever burns.</p><p><b>RESULTS</b>The myocardial water content and AQP1 expression increased significantly 2 h after the burn injury, reaching the peak levels at 12 h and remaining higher than the normal level at 48 h. A significant positive correlation was found between myocardial water content and AQP1 expression in the rats (r=0.868, P<0.01).</p><p><b>CONCLUSION</b>The severity of myocardial edema after severe burn is correlated to the expression level of AQPl protein, suggesting the important role of AQPl protein in pathological progression of myocardial edema.</p>

Effect of liposome-mediated HSV-tk gene transfer on fibroblast apoptosis in rats with scald injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of HSV-tk gene transfer on the apoptosis of fibroblast in rats with scald injury.</p><p><b>METHODS</b>The recombinant eukaryotic expression vector pcDNA3.1/tk was transfected via liposome in the skin of rats with scald injury. The expression of tk gene was detected by RT-PCR technique, and after GCV injection, the apoptosis of the fibroblasts positive for tk gene was observed under transmission electron microscope.</p><p><b>RESULTS</b>Liposome-mediated HSV-tk gene transfection of the rat skin resulted in the positive expression of tk gene in the fibroblasts in the burn wound. GCV injection induced the apoptosis of the positively transfected fibroblasts.</p><p><b>CONCLUSION</b>HSV-tk gene transfer mediated by liposome can promote the apoptosis of the fibroblasts in rats with scald injury.</p>

Effect of early enteral feeding on the expression of aquaporin 1 in edematous small intestinal tissues of rats after severe burn / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in the expression of aquaporin 1 (AQP-1) in edematous small intestinal tissues of rats after severe burn and the effect of early enteral feeding on its expression.</p><p><b>METHODS</b>Ninety normal adult Wistar rats were randomly divided into normal control group (n=6), burn model group (n=42, with 30% TBSA III degrees) and early feeding group (n=42). Dry weight method, ELSIA and immunohistochemistry were used to observe and detect the water content and expression of AQP-1 in the intestinal tissue at 1, 4, 8, 12, 24, 48, and 72 h after the burns.</p><p><b>RESULTS</b>In the burn model group, the water content in the intestinal tissue increased at 4 h after the injury, reaching the peak level at 48 h; AQP-1 expression decreased at 8 h after severe burn and reached the lowest level at 48 h. AQP-1 expression level showed a significant inverse correlation to the water content (P<0.01). Compared with the burn model group, the rats in the early feeding group showed increased AQP-l expression and lessened edema in the small intestines, also demonstrating an inverse correlation between water content and AQP-l expression (P<0.01).</p><p><b>CONCLUSION</b>Intestinal AQP-1 expression gradually decreased and edema worsened in rats early after severe burn, reaching the lowest or the peak levels 48 h after the injury with an inverse correlation between them. Early enteral feeding can increase the expression of AQP-l in the small intestine to ameliorate the intestinal edema in rats with severe burn injury.</p>

Study on cotransfection of genes of insulin-like growth factor I and herpes simplex virus thymidine kinase for optimization of wound healing / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the effect of cotransfection of genes of insulin-like growth factor I (IGF-I) and herpes simplex virus thymidine kinase (HSV-tk) on wound healing.</p><p><b>METHODS</b>Thirty male Wistar rats were inflicted with 30% TBSA full-thickness scald. They were then divided into A group (4.6 microg pcDNA3.1/IGF-I+Lipofectamine 2000+saline), B group (3.6 microg pcDNA3.1/HSV-tk+Lipofectamine 2000+saline), C1 group and C2 group (2.3 microg pcDNA3.1/IGF-I+1.8 microg pcDNA3.1/HSV-tk+Lipofectamine 2000+saline), and D group (3.0 microg pcDNA3.1+Lipofectamine 2000+saline) according to the random number table, with 6 rats in each group. The above-mentioned mixtures were subcutaneously injected into left back of each rat the moment after injury and on post scald day (PSD) 7, 14, 21, and 28. Gancyclovir (2.5 mg/100 g) was hypodermically injected into rats in C2 group on PSD 29, 30, 31, 32. Changes in body weight of rats were measured. Wound healing rates were calculated. On PSD 35, the expressions of IGF-I gene in local wound and liver tissue were determined with immunohistochemical staining. The serum expression of IGF-I was determined with radioimmunoassay. Expression of HSV-tk gene in local wound was determined with RT-PCR. Apoptosis of fibroblast in C1 and C2 groups was observed under transmission electron microscope. Data were processed with one-way analysis of variance and Turkey method.</p><p><b>RESULTS</b>Body weight of rats in A, C1, and C2 groups increased from PSD 7 through 35, and the difference between former three groups and B, D groups was statistically significant (with F value respectively 2.764, 4.519, 5.009, 13.449, 5.877, P values all below 0.05). Wound healing rates of rats in A, C1, and C2 groups were higher than those in B, D groups (with F value respectively 5.286, 100.880, 152.380, 127.850, 147.750, P values all below 0.05). IGF-I gene was positively expressed in wound fibroblast in A, C1 and C2 groups, but negatively in liver tissues of all the rats. There was no significant statistical difference among groups in serum content of IGF-I [from (1185+/-170) to (1270+/-130) ng/mL, F=0.355, P=0.838]. HSV-tk gene was positively expressed in rat skin tissue in B, C1 and C2 groups. Fibroblast apoptosis was observed under transmission electron microscope in C2 group, but it was not observed in C1 group.</p><p><b>CONCLUSIONS</b>Cotransfection of pcDNA3.1/IGF-I and pcDNA3.1/HSV-tk mediated by liposome can promote wound healing, and inhibit the scar proliferation to some extent.</p>

Effect of local treatment with cooling and spray film on early edema of superficial II degree scald burns in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the anti-inflammatory effect of early local treatment with cooling and spray film on scald burn injury in rats.</p><p><b>METHOD</b>Seventy-five Wistar rats were randomly divided into 5 groups including the sham-scalded group, untreated scald group, cooling group, spray film group, and cooling plus spray film group with corresponding treatments. After gross observation of the wounds, the tissues at the wounds were sampled at different time points after the injury to determine the total water content (wet: dry weight ratio) and prostaglandin E(2) (PGE(2)) levels using radioimmunoassay (RIA).</p><p><b>RESULTS</b>Treatment with cooling and spray film significantly alleviated the swelling and effusion of the scald burns. At each of the time points, the water content and PGE(2) levels in the cooling group, spray film group and cooling plus spray film group were all lower than those in untreated scald group (P<0.01), but all higher than those in the sham-scalded group (P<0.01). The water content and PGE(2) levels were the lowest in cooling plus spray film group, and a significant correlation was noted between the water content and PGE(2) levels in the untreated scald group, cooling group, spray film group and cooling plus spray film group (P<0.01).</p><p><b>CONCLUSIONS</b>Local treatment with cooling and spray film can alleviate the edema of superficial II degree scald burns in rats probably by reducing the levels of the inflammatory cytokines in the local tissues.</p>

Sequential management of residual wounds in burn patients / 中华烧伤杂志

<p><b>OBJECTIVE</b>To seek a sequential method for the management of residual wounds in burn patients.</p><p><b>METHODS</b>Three chronic residual wounds on each of 25 burn patients were either covered with vaseline gauze (A group), human tissue-engineered active skin (Active Skin, B group) or Active Skin after rinsing with fluid containing oxygen and vacuum assisted drainage ( C group) on wounds. The contents of (TNF)a in granulation tissue were assayed by enzyme linked immunosorbent assay (ELISA). Expression of metalloproteinase-13 (MMP-13) mRNA in granulation tissue was determined with reverse transcription polymerase chain reaction (RT-PCR). Moreover, quantity of wound bacteria in the wounds and wound healing rate were determined with usual method.</p><p><b>RESULTS</b>The quantities of wound bacteria in C group on 3,6,9, 12 post-treatment day( PTD) were (5.30 +/- 1.60), (1.30 +/-0.80) , (1.70 +/- 0. 60)and (0.60 +/-0. 10)clone formation unit/ml( CFU/ml) , respectively, which were obviously lower than those in A and B groups. The contents of TNFa and expression of metalloproteinase-13 (MMP-13) mRNA in granulation tissue in C group on 6 PTD were [ (0. 650 +/- 0. 040) ng/mg and 0. 210 +/- 0. 010,] ,respectively, and they were evidently lower than those in A group [(1.550 +/-0. 370)ng/mg,1. 040 +/- 0. 050, P <0.01] and B group (0. 810 +/- 0.080) ng/mg, 0.640 +/- 0.030, P <0.01]. Meanwhile, the contents of (TNF)a and expression of MMP-13 mRNA in B group were also obviously lower than those in A group. The wound healing ratio in C group on 15 and 30 PTD were markedly higher than those in A or B group ( P <0.01).</p><p><b>CONCLUSION</b>Covering the residual burn wounds with Active Skin after rinsing with fluid containing oxygen followed by vacuum assisted drainage can improve repairing of residual burn wounds.</p>

Experimental study of gene transfer of insulin-like growth factor I on wound healing of scald rats / 中华整形外科杂志

<p><b>OBJECTIVE</b>To probe into the effect of IGF-I gene transfer on wound healing of scald rats.</p><p><b>METHODS</b>Eukaryotic recombinant plasmid of pcDNA3.1/ IGF-I (successfully constructed by our study group earlier) transported by liposome were injected subdermally in wound region of scald rats. Changes of body weight and tendency of wound healing were observed carefully within 5 weeks postburn. The expression of IGF-I gene transfer in serum and liver was observed with immunohistochemical staining.</p><p><b>RESULTS</b>The results of animal experiment showed that IGF-I gene transported by liposome expressed positively in fibroblast in burn wound, but expressed negatively in liver tissue with immunohistochemical staining, There were no significant differences for IGF-I concentrations in serum among treatment group and control group (P > 0.05). The speed of wound healing for animals injected with IGF-I reconstruct was faster than those which didn't injected IGF-I (P < 0.05); The body weight of the animals in the group injected with IGF-I hadn't a loss in 5 weeks postburn, but those which didn't injected IGF-I had a loss in body weight during postburn days ( P < 0.05).</p><p><b>CONCLUSIONS</b>Gene transfer of IGF-I transported by liposome can promote wound healing, and it also could avoid some adverse effect brought by application of IGF-I systematically .</p>

Effect of nuclear factor-kappaB activation on expression of proinflammatory cytokines in rat lung tissues in early stage of burn injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of nuclear factor-kappaB (NF-kappaB) activation on the expression of proinflammatory cytokines in the lung tissues of rats with early-stage burn injury.</p><p><b>METHODS</b>Wistar rats were randomly divided into 3 groups, namely the normal control, burn, burn and PDTC treatment groups, and in the latter two groups, the rats were subjected to 35% TBSA full-thickness burns. Activation of pulmonary NF-kappaB at 1, 3, 6, 12, and 24 postburn hour (PBH) was tested by electrophoretic mobility shift assay , and the expressions of pulmonary tumor necrosis factor alpha (TNF alpha) and interleukin-8 (IL-8) mRNAs at 3, 6, 12, and 24 h were detected by RT-PCR.</p><p><b>RESULTS</b>Compared to that of the control group, activity of pulmonary NF-kappaB in burned rats was markedly increased within 1 PBH and kept increasing till 24 h. Expressions of pulmonary TNF alpha and IL-8 mRNAs increased gradually, reaching the peak level at 6 PBH, and PDTC could effectively inhibit pulmonary NF-kappaB activation and expression of the pulmonary cytokines induced by the burn injury.</p><p><b>CONCLUSION</b>Severe burn injury may activate pulmonary NF-kappaB, which ultimately leads to secretion of cytokines in the lung tissues.</p>

Influence of epidermis from different sources on the proliferation and collagen content of fibroblasts / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of epidermis from different sources on the proliferation and metabolism of fibroblasts (Fb), and to explore its cause.</p><p><b>METHODS</b>In a co-culture system, normal Fb (A group) and cicatricial Fb(B group) from 10 patients with scar during proliferative stage were co-cultivated with own normal skin epidermis (NSE), respectively, without direct contact. In control groups (C group), cicatricial Fb was cultured alone. Normal Fb and cicatricial Fb from 10 patients with scar during maturation period were co-cultured with own normal skin epidermis as mentioned above, and divided into D, E and F groups. The cell number of FB, the amount of type I and III procollagen (PC I, PC III) in the supernatants and the PC I to PC III ratio were determined.</p><p><b>RESULTS</b>To compare the C with A group and the F with D group, Fb in C and F groups exhibited increased cell number and PC I , PC III amounts (P < 0.05), and decreased ratio of PC I to PC III (P < 0.05). To compare the B with C group, PC III contents in the cell supernatant was increased (P < 0.05), and the ratio of PCI to PC III decreased in B group (P < 0.05), there were no obvious difference in Fb cell number and the amount of PC I contents between B and C group. To compare the E with F group, the cell number of Fb, as well as PC I and PC III contents in cell supernatant were obviously decreased in E group (P < 0.05), but no obvious decrease was observed in the ratio of PC I and PC III. To compare the B with A group and the E with D group, the cell number and the PC I and PC III contents in B and E groups were evidently increased, while the ratio of PC I to PC III decreased markedly (2.20 +/- 0.27 vs 1.16 +/- 0.21 in A, B group, P < 0.05; 2.18 +/- 0.14 vs 1.93 +/- 0.26 in D, E group, P < 0.05).</p><p><b>CONCLUSION</b>Normal epidermis may play an important role in preventing hypertrophic scar by producing some bioactive substances.</p>

Influence of substance P on the proliferation and apoptosis of fibroblasts of pathological scars / 中华烧伤杂志

<p><b>OBJECTIVE</b>To further explore the effects of substance P on the proliferation and apoptosis of fibroblasts obtained from pathological scars in vitro.</p><p><b>METHODS</b>Fibroblasts from keloid (KSF) , hypertrophic scar (HSF) and normal dermis (NDF) of 12 burn patients were cultured in vitro and divided into control, SP (with 1 x 10 (-6) mol/L SP added to the culture medium) , and SP + spantide( with 1 x 10 (-6) mol/L SP and 3 x 10 (-5) mol/L spantide added to the culture medium) groups. MTT method or flow cytometry assay was used for the determination of the proliferative activities or apoptotic rate of fibroblasts obtained from KSF, HSF and NDF with SP or Spantide. And then the fibroblasts in SP group were subdivided into 1 x 10( -9) -1 x 10 (-5) mol/L groups to examine the time-or dose-effect of SP to fibroblasts from different sources.</p><p><b>RESULTS</b>In control group, different types of fibroblasts exhibited similar proliferative activities and apoptotic rates. But there was significant difference in these indices between control and SP group (the proliferative activity of KSF, HSF, NDF was 0. 656+/-0. 071, 0. 525 +/-0. 064, 0. 404+/-0. 063, respectively; and the apoptotic rate of KSF, HSF, NDF was [( 1.5+/-0.3) % , (4.0+/-0.5) % , (5.5+/-0.7) % , respectively],( P < 0. 05). SP had stronger effect on KSF than it did to HSF, as well as it had stronger effect on HSF than it did to NDF. In SP + spantide group, the effect of SP on KSF was partially inhibited, while it was completely inhibited in cultures of HSF and NDF. KSF was more sensitive to SP and the effect was longer when compared with HSF.</p><p><b>CONCLUSION</b>SP may play an important role in the process of pathological scar formation due to its diverse effects on fibroblasts from different sources.</p>

The role of nuclear factor-kappaB in the burn serum-induced expression of intercellular adhesion molecules-1 in endothelial cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the role of nuclear factor-kappaB (NF-kappaB) in the burn serum induced expression of intercellular adhesion molecules-1 (ICAM-1) in endothelial cells.</p><p><b>METHODS</b>Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and divided into control (with normal serum stimulation), burn serum (B, with burn serum stimulation) and PDTC (with burn serum and PDTC stimulation) groups. The NF-kappaB activity in endothelial cells was determined with electrophoretic mobility shift assay (EMSA) at 0.5, 1.0, 2.0, 4.0 post-stimulation hour (PSH). The expression of ICAM-1 at 3.0, 6.0, 12. 0, 24.0 PSH was detected by flow cytometry.</p><p><b>RESULTS</b>The NF-kappaB activity in endothelial cells in burn serum group and PDTC group were markedly higher than that in control group (P <0.01), and it reached the peak at 1.0 PSH [(21.03 +/- 4.87), (7.44 +/- 0.60) x 10(4) A], respectively, then gradually decreased. But it was obviously lower in PDTC group than that in burn serum group ( P <0. 01 ). The expression of ICAM-1 was gradually increased in both burn serum group and PDTC group, reaching the peak level at 12.0 PSH [(327 +/- 37), (142 +/- 31) mean fluorescence intensity], respectively, which were significantly higher than that in control group (P <0.01). But it was evidently lower in PDTC group than that in burn serum group at 12.0 and 24.0 PSH (P <0.01).</p><p><b>CONCLUSION</b>Burn serum can initiate the synthesis and release of adhesion molecules in endothelial cells through activation of NF-kappaB, indicating that NF-kappaB plays an important role in the process of burn serum induced endothelial secretion of adhesion molecules.</p>

Effect of NF-kappaB activation on the early expression of tumor necrosis factor alpha and myocardial dysfunction in burned rats / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effect of NF-kappaB activation on the early expression of proinflammatory cytokines in myocardium and early myocardial dysfunction in burn rats.</p><p><b>METHODS</b>One hundred and seventy Wistar rats were enrolled in the study and randomly divided into three groups, i. e. control( C, n = 20, with isotonic saline solution) , burn ( B, n = 90, with isotonic solution after burns) and pyrrolidine dithiocarbamate (PDTC, n =60, with isotonic saline and 250 mg/kg PDTC after burns) groups. The rats in B and PDTC groups were inflicted with 35% TBSA full-thickness burns on the back. The activity of myocardial NF-kappaB was determined by electrophoretic mobility shift assay at 1 , 3, 6, 12,24 postburn hours (PBH), with expression of integral absorbance ( A ) value . The expression of myocardial tumor necrosis factor alpha ( TNF-alpha) mRNA was assessed by reverse transcription polymerase chain reaction( RT-PCR) and in situ hybridization at 6, 12 PBH, with expression ofA value. The left ventricular systolic pressure( LVSP) , the left ventricular end diastolic pressure (LVEDP) ,the maximum rate of rise of left ventricular pressure ( +/- dp/dt max) were also observed at 3, 6, 12,24 PBH. RESULTS The activity of myocardial NF-KB in B group was markedly increased at 1 PBH [ (20. 3+/-3. 4) x 104A ] ,which was obviously higher than that in C group (2. 2 +/- 0. 4) x 104A , P <0.01]. It peaked at 3 PBH, and was still evidently higher than that in C group at 24 PBH ( P <0. 01). The expression of TNF-alpha mRNA was obviously higher than that in C group at 3 PBH ( P < 0. 01) , peaking at 6 PBH, and it was mainly expressed in myocardium. The expression of LVSP and +/- dp/dt max were lower, but LVEDP was higher than that in C group during 3 -24 PBH ( P <0.01).</p>

Effect of escharectomy on rats'pulmonary NF-?B activation in early stage of burn injury / 中华急诊医学杂志

Objective To investigate the effect of escharectomy on rats' pulmonary NF-?B activation and the expression of pulmonary proinflammatory cytokines in early stage of burn injury.Method Wistar rats were randomly divided into three groups:group A(control group),group B(postburn without escharectomy),group C(escharectomy at early stage of burn injury).Thermal-injuried rats underwent 35% TBSA full-thickness burns. Activation of pulmonary NF-?B at 12 hours and 24 hours postburn was tested by electrophoretic mobility shift assay (EMSA),and at the same time expressions of pulmonary TNF-?mRNA were measured by reverse transcription polymerase chain reaction(RT-PCR)and release of pulmonary TNF-?were assayed by enzyme-linked immunosorbent assay(ELISA).Results Compared with control group,activity of pulmonary NF-?B in group B was markedly increased,reached(19.56?1.36)?10~4 A at 12 hours and(15.23?1.94)?10~4 A at 24 hours,which was higher than that in group A[(4.36?0.38)?10~4 A,P