[Study on the biological function of dermal fibroblasts in the wounds of diabetic and non-diabetic rats with deep burns].

OBJECTIVE: To explore the changes of the biological function of dermal fibroblasts (FBs) in the wounds of diabetic and non-diabetic burned rats and the pathogenesis of impaired wound healing in diabetes. METHODS: 80 Sprague-Dawley (SD) rats weighing 220 g were randomly divided into control and STZ-induced diabetic groups, and then deep partial thickness scald involving 10% TBSA was reproduced in the two groups. The diabetic groups were randomized into pre-scalding, post-scalding day (PSD 3), PSD 7, PSD 14 and PSD 21 groups, with 6 rats in each group. Controls were also randomized into 5 groups. Skin specimens from the wound were harvested at each time point. Cell cycles of FBs were analyzed with flow cytometry. The amount of hydroxyproline in the skin tissue was assessed on 0, 3, 7, 14, and PSD 21. The type I and III collagens were determined by ELISA. The expression of alpha-SMA in the dermal fibroblasts of each group was assessed by immunohistochemistry method. Transmission electron microscopy was used to observe the ultrastructure changes of FBs. RESULTS: Compared with that in the normal rats, the percentage of the cells in G(0)/G(1) phase in the DM group was evidently lower on PSD 0 (65.79 +/- 5.24 vs 82.43 +/- 9.68, P < 0.01). After the scalding, the percentage of the cells in G(0)/G(1) phase in DM group was significantly higher (70.00 +/- 4.27 vs 42.04 +/- 12.96, on PSD 3, P < 0.01), meanwhile the percentage of S phase was remarkably lower than those in C group on 3, 7, 14, 21PSD (P < 0.05, P < 0.01). The amount of hydroxyproline in the diabetic skin tissue was obviously lower than those of the responding control groups before (0.72 +/- 0.06 vs 1.42 +/- 0.28, P < 0.01) and after burn injury (P < 0.01). Furthermore, the rate of I/III collagen on 7, 14 and PSD 21 was much higher in DM group than that in C group (P < 0.01). The expression of alpha-SMA in DM groups on PSDS 3, 7, 14 and PSD 21 was evidently lower than those of the controls (levels 10.28 +/- 3.99, C group 28.42 +/- 2.73, on PSD 14, P < 0.01), although that inclined to be heightened after burn injury. Ultrastructure changes of FBs in the wounds of diabetic rats could be observed, such as the outstretched endoplasmic reticulum, un development of Golgi's body, lackness of microtubule and microfilament, a sharp increase of cytolysosomes, and so on. CONCLUSION: The FB proliferation in the diabetic skin is abnormal, the synthetical ability of collagen is weakened, the expression of alpha-SMA is insufficient, the microtubule and microfilament is lack, and the number of cytolysosomes increases. The pathogenesis of impaired-wound healing in diabetics might be related with the above mentioned factors.

[Proliferation-inhibiting effect of advanced glycation end products modified human serum albumin to vascular endothelial cell ECV304].

OBJECTIVE: To study the proliferation-inhibiting and apoptosis-inducing effects of advanced glycation end products (AGE) modified human serum albumin (AGE-HSA) on human vein endothelial cells. METHODS: Human umbilical vein endothelial cells ECV304 were cultured in vitro with AGE-HSA of the concentrations of 12.5, 25, 50, 100, and 200 micro g/ml for 6, 12, 24, or 48 hour, then 20 micro l of 5 mg/ml MTT were added and the optical density (OD) at each time point was determined. Another ECV304 cells were cultured with AGE-HAS for 2, 4, or 8 days and then were stained with trypan blue to calculate the number of dead cells so as to calculate the proliferation-inhibiting rate. Another ECV304 cells were cultured with AGE-HAS for 6, 12, 24, or 48 hours and then stained with annexin V Fitc and propidium iodide (PI). Flow cytometry was used to calculate the annexin V Fitc positive cells (early and middle stage apoptotic cells) and Annexin V Fitc/PL positive cells (late apoptotic cells). Inverted microscope, transmission electron microscope, and fluorescence microscope were used to observe the histological changes of apoptotic cells. FCV304 cells incubated with HSA of the above-mentioned and without addition of the other agents concentrations were used as controls. RESULTS: The OD values of ECV304 cells cultured for 48 h with low concentrations (12.5, 25, and 50 micro g/ml) of AGE-HSA were not significantly different from those of the control (1.104 +/- 0.080, 1.098 +/- 0.097 and 1.059 +/- 0.122 VS. 1.159 +/- 0.088, all P > 0.05). The OD values of ECV304 cells cultured with low concentrations of AGE-HSA for 4 days and 6 days were significantly lower than those in the control group. The OD values of ECV304 cells cultured with high concentrations (100 and 200 micro g/ml) of AGE-HSA for 6 - 48 hours decreased to 0.117 +/- 0.033 and 0.081 +/- 0.020 in comparison with that of the control group (P < 0.01). Flow cytometry and fluorescence microscopy showed higher proportions of apoptotic cells among the ECV304 cells cultured with high concentrations of AGE-HAS than among the control cells at each time point (P < 0.01). The numbers of cells in the control group exponentially increased after culture for 2, 4, and 6 days. The number of cells cultured with low concentrations of AGE-HAS for 2 days was not significantly different from that of the control group (P > 0.05), however, the numbers of cells cultured with low concentrations of AGE-HAS for 4 and 6 days were significantly lower than those of the control group (both P < 0.01). The numbers of cells cultured with 100 or 200 micro g/ml AGE-HAS for 2 days were significantly lower than those of the control group (both P < 0.01) with a proliferation-inhibiting rate of 39.56% +/- 2.82% and 60.32% +/- 4.51% respectively. The apoptotic rates in cells cultured with low concentrations of AGE-HAS for 48 hours were not significantly different from those in the control group. The apoptotic rates in cells cultured with 100 or 200 micro g/ml AGE-HAS for 6, 12, 24, or 48 hours were significantly higher than those in the control group (all P < 0.01). The apoptotic rates in 200 micro g/ml group at different time points were significantly higher than those in the 100 micro g/ml group (P < 0.05 or 0.01). The apoptotic rate and number of apoptotic cells increased along with the increase of culture time and concentration of AGE-HAS. Microscopy showed morphological changes among the cells cultured with 100 micro g/ml AGE-HAS for 6, 12, 24, and 48 hours and the numbers of apoptotic cells, mainly late apoptotic cells, and dead cells increased remarkably since the cells were cultured for 48 hours. CONCLUSION: AGE-HSA inhibits the proliferation of vascular endothelial cells and induces apoptosis in dose and time dependent manner. AGE modification-induced pathobiological cascade may be involved in the pathogenesis of impaired wound healing in diabetes by the mechanism of angiogenesis retardation.

[Initiation of systemic administration of antibiotics in treatment of invasive infection of burns].

OBJECTIVE: To optimize the systemic antibiotics in the treatment of the invasive infection of burns based on the successive monitoring of bacterial species harvested from the burn wound and subeschar tissues and their resistance to antibiotics. METHODS: The data of bacteriological monitoring of burn wound and subeschar tissues in our burn center from 1995 to 2000 were retrospectively analyzed, and the characteristics of distribution and resistance to antibiotics of 1 109 strains from the wound in 612 patients and subeschar tissues in 146 patients were compared statistically by dividing them into two periods, i.e. from 1995 to 1997 and 1998 to 2000, respectively. RESULTS: The percentage of Gram negative bacilli in identified strains was significantly higher than that of Gram positive cocci, and the majority of them were Pseudomonas and Enterobacteriaceae; Staphylococcus aureus comprised the majority of Gram positive cocci from 1998 to 2000, compared with the data collected in the period of from 1995 to 1997. The resistance of the Gram negative bacilli to Cephalosporins and Amikacin was increasing while the resistance of Pseudomonas to Netilmicin was decreasing from 18.52% of the tested strains down to 5.83%, and the resistance of Enterobacteriaceae to it was increasing from 18.75% to 55.79%. In addition, the resistance of Staphylococcus aureus to Netilmicin was down from 28.13% to 4.70%. Enterobacteriaceae were still sensitive to Imipenem, while the resistance of Pseudomonas to it became higher than that in the period from 1995 to 1997. CONCLUSION: The percentage of Gram negative bacilli in identified strains is significantly higher than that of Gram positive cocci and the pattern of their resistance to the antibiotics is changed meanwhile. Therefore, the choice of antibiotics for initial treatment of invasive infection in severe burns is a combination of Netilmicin and Imipenem, and, if Gram positive cocci is highly suspected, the first choice is Vancomycin.

A randomized and controlled multicenter prospective study of the Chinese medicinal compound Fufang Xuelian Burn Ointment for the treatment of superficial and deep second-degree burn wounds.

The objective of this study was to evaluate the efficacy and safety of a traditional Chinese medicine, Fufang Xuelian Burn Ointment (FXBO), to treat superficial and deep second-degree burn wounds. A four-center, randomized, controlled, and prospective study was conducted. Overall, 240 patients with either superficial or deep second-degree burn wounds were enrolled consecutively in this study. Patients who were randomly assigned to the control group (superficial: 72, deep: 48) underwent common burn wound therapy, whereas those randomized to the treatment group (superficial: 72, deep: 48) received common burn wound therapy plus topical FXBO. The healing rate, healing time, effective rate, and safety data were compared between the two groups. The baseline characteristics were comparable for the two groups. The healing rate was 94.79(±7.50) in the control group and 98.60(±5.69) in the FXBO group after 14 days for patients with superficial second-degree burn wounds (P = 0.000), and 95.17(±9.68) versus 97.44(±9.81) at 28 for deep second-degree burn wounds (P = 0.025). The median healing time in the FXBO group were 9 and 21 days for superficial and deep second-degree burns, respectively, compared to 10.5 and 22.5 days, respectively, in control group (P(superficial) = 0.000 and P(deep) = 0.009). The results of the effective rate showed that comprehensive efficacy of the FXBO group was improved compared to the control group for either superficial or deep second-degree burns (P(superficial) = 0.035 and P deep = 0.003). There were no reported drug-related adverse events in both groups. Therefore, FXBO was well tolerated and more effective than control group for treating superficial and deep second-degree burn wounds.

[Protective effect of early application of lytic cocktail on small intestine of severely scalded rats].

OBJECTIVE: To study the protective effect of early application of lytic cocktail on small intestine of severely scalded rats. METHODS: Sixty-six male SD rats were divided into sham injury group (SI, n=6), scald group (S, n=30) and scald+lytic cocktail group (SL, n=30) according to the random number table. After anesthesia, rats in the latter 2 groups were inflicted with 30% full-thickness scald, while rats in S group were sham scalded with 37 degrees C water. Resuscitation was carried out by intraperitoneal injection with 2 mLxkg(-1)x%TBSA(-1) lactated Ringer's solution in all rats; meanwhile 12 mL/kg lytic cocktail [1 mL pethidine (50 mg/mL)+1 mL chlorpromazine (25 mg/mL)+1 mL promethazine (25 mg/mL)+125 mL saline] was hypodermically injected to rats in SL group, while 12 mL/kg saline was injected into rats in the other 2 groups. Samples of blood and small intestine were harvested from S and SL groups at post scald hour (PSH) 3, 6, 12, 24, 48 and from SI group at PSH 3, with 6 rats in each group at each time point. Pathological changes in intestine were observed, and the expression of intercellular adhesion molecule 1 (ICAM-1) and CD68 were determined with immunohistochemistry at PSH 24 for S and SL groups and at PSH 3 for SI group. Plasma levels of D-lactate, diamine oxidase (DAO), IL-1beta, TNF-alpha, IL-10 were determined with ELISA. Data were processed with one-way analysis of variance. RESULTS: (1) At PSH 24, mild hemorrhage, inflammatory cell infiltration and epithelial cell shedding were observed in small intestinal mucosa of rats in S group. Compared with S group, the intestinal villi of SL group were arranged regularly without obvious hyperemia and edema. (2) Expression levels of ICAM-1 and CD68 [(1.69+/-0.27)%, (0.80+/-0.09)%] in S group were significantly higher than those in SI group [(0.77+/-0.10)%, (0.30+/-0.05)%, with F value respectively 77.303 and 66.933, P<0.05 or P < 0.01] and SL group [(0.53+/-0.09)%, (0.32+/-0.06)%, with F value respectively 77.303 and 66.933, P values all below 0.01]. (3) D-lactate levels of rats in SL group were significantly lower than those of rats in S group at PSH 12, 24 (with F value respectively 20.936 and 19.854, P values all below 0.01), while DAO levels of rats in SL group were significantly lower than those of rats in S group at PSH 3, 12 (with F value respectively 21.930 and 11.342, P values all below 0.05). (4) The levels of IL-1beta and TNF-alpha in S group were significantly higher than those of SI group at each time point (P values all below 0.01). The levels of IL-1beta and TNF-alpha in SL group were significantly higher than those of S group at PSH 6, 12 and 24 (with F value respectively 96.517, 17.365, 79.715 and 21.328, 17.682, 28.424, P<0.05 or P<0.01). IL-10 level in SL group was higher than that in S group at each time point, and the differences were statistically significant at PSH 6 and 24 (with F value respectively 8.668, 19.634, P < 0.05 or P<0.01). CONCLUSIONS: Early administration of lytic cocktail can attenuate edema and injury of intestinal mucosa in severely scalded rats. The mechanism may lie in that it can reduce the expression of ICAM-1 in intestinal mucosa, decrease the number of intestinal inflammatory cells and regulate the levels of inflammatory cytokines.

[To intensify our understanding about management of severe burn infection].

Nowadays, it is necessary to emphasize the three basic inseparable elements in the treatment of severe burn infection, which are systemic care, burn wound care, and rational use of antimicrobials topically or systematically. Systemic care has been shifted from simple nutritional support to maintaining the systemic homeostasis, including balancing immune-inflammatory response, and protecting organs from dysfunction. Some work focused on regulating systemic immune response in the initial phase and the balance of inflammatory response after occurrence of severe burn infection have been reported. These results at least broaden our thinking to recognize that treatment should not only destroy microbes, but also balance the response of the body. Escharectomy in earlier phase has been a consensus. Currently, we turn our vision into how to use "damage control surgery (DCS)" concept in management of severe burn. DCS in burn care includes the evaluation of perioperative situation more accurate to make a more appropriate surgical decision. Meanwhile, an overall strategy should be established to confront the rapidly increasing drug resistance of the pathogens. The release of endotoxin after use of antimicrobials, which has been studied widely, should be explored further.

[Comparison between intermingled skin transplantation and microskin grafting in repairing massive deep burn].

OBJECTIVE: To study difference in curative effect between intermingled skin transplantation (IT) and microskin grafting (MG) in repairing massive deep burn. METHODS: Clinical materials of 101 patients with massive deep burn hospitalized from 1992 to 2008 were retrospectively summarized. Patients were divided into IT group (n = 52) and MG group (n = 49). The size of initial donor site for autologous skin, the wound size initially covered with autologous skin, the survival rate of initial autologous skin grafting, the theoretical expansion multiple of the autologous skin, the actual expansion multiple of the autologous skin, the total size of donated autologous skin, the remained wound condition, and the function of large joint of patients in two groups were compared. RESULTS: In IT group and MG group, the size of initial donor site for autologous skin was respectively (3.25 +/- 0.48)%TBSA and (3.01 +/- 0.21)%TBSA, the wound size initially covered by autologous skin was respectively (30.4 +/- 3.6)%TBSA and (41.4 +/- 1.3)%TBSA, the survival rate of autologous skin grafting was respectively (99.9 +/- 1.9)% and (87.5 +/- 6.8)%, the theoretical expansion multiple of the autologous skin was respectively 9.5 +/- 1.3 and 13.9 +/- 1.4, the actual expansion multiple of the autologous skin was respectively 9.5 +/- 1.3 and 12.0 +/- 1.5, the difference between two figures of each index was statistically significant (P < 0.05). There was no statistical significant difference between IT and MG group in respect of the total size of donated autologous skin [respectively (14.2 +/- 1.9) and (14.0 +/- 2.1)%TBSA, P > 0.05]. There were 23 patients (44.2%) with residual wounds over 0.5%TBSA in IT group, and 37 cases (75.5%) in MG group. There were 34 patients (65.4%) with good function of large joints in IT group, and 18 cases (36.7%) in MG group. CONCLUSIONS: Expansion multiple of autologous skin after MG is obviously larger than that after IT, thus limited skin source can be fully used. The wound healing quality and the restoration of large joint function of patients treated with IT are better than those of patients treated with MG.

[Effect of different immunomodulation on inflammatory response in burn rats with sepsis].

OBJECTIVE: To investigate the effect of Thymosin and growth hormone(GH) on inflammatory response in burn rats or burn rats with sepsis. METHODS: Sixty-four SD rats were randomly divided into normal control group (NC, without treatment), sepsis group (S, with injection of LPS), sepsis + Thymosin group (ST, with successive injection of Thymosin and LPS), sepsis + GH group [SGH, with successive injection of recombinant human GH (rhGH) and LPS], burn group, burn + sepsis group (BS, with injection of LPS after burn), burn + sepsis + Thymosin group (BST, with successive injection of Thymosin and LPS after burn), burn + sepsis + GH (BSGH, with successive injection of rhGH and LPS after burn), with 8 rats in each group. Specimens of spleen tissues were harvested to determine HLA-DR in lymphocyte and evaluate inflammatory cell infiltration (score). Specimens of peripheral blood were collected to determine Toll-like receptor 4 (TLR4) level in monocyte and serum level of TNF-alpha, IL-4, IL-6, IL-10. RESULTS: Compared with those in NC group, serum level of IL-10 in S group decreased obviously, while other indices increased obviously (P < 0.01). The levels of HLA-DR and TLR4 and serum level of TNF-alpha were similar between SGH and ST groups (P > 0.05). Compared with those in SGH group [(2.87 +/- 0.04) score, and IL-6 (0.0083 +/- 0.0018) microg/mg, IL-4 (0.0102 +/- 0.0021) microg/mg, IL-10 (0.0310 +/- 0.0027) microg/mg, respectively], degree of inflammatory cell infiltration (1.50 +/- 0.76) score and serum levels of IL-6, IL-4, IL-10 of rats in ST group decreased obviously (0.0064 +/- 0.0012, 0.0058 +/- 0.0024, 0.0230 +/- 0.0021 microg/mg, respectively, P < 0.01). The levels of HLA-DR, TLR4 and inflammatory cell infiltration degree of spleen in B group were respectively higher than those in NC group and lower than those in BS group. Compared with those in NC group, serum levels of TNF-alpha, IL-6 in B group increased significantly, while IL-4, IL-10 showed an opposite tendency. There was no obvious difference between BST and BSGH groups in serum levels of HLA-DR and IL-6 (P > 0.05). Compared with those in BST group, inflammatory cell infiltration degree in spleen and the levels of TLR, TNF-alpha obviously decreased (P < 0.01), while IL-4 and IL-10 levels increased in BSGH group (P < 0.01). CONCLUSIONS: Inhibitive effects between Thymosin and GH on extensive inflammatory reaction were similar with or without trauma, and GH has better effect as compared with Thymosin when with trauma.

[The intermingled transplantation used in severe burn patients after eschar excision].

In the early developing stage of burn surgery, severe burn patients with large and deep burn wound often died of complications because of shortage of auto-skin. The method of intermingled transplantation composed of a large sheet of partial thickness allo-skin with punched holes for in laying small pieces of partial thickness auto-skin was first advocated by Chinese doctors (Ruijin Hospital) in 1960's. This intermingled transplantation method has saved many severe burn patients with extensive full-thickness burn wound. The mortality rate of severe burn patients has decreased and the survival rate has increased remarkably since the intermingled transplantation treatment method used in the burn units. In this paper we review the process of formation of intermingled transplantation and the mechanisms of success of this Chinese method in repairing the large wound surface area after eschar excision. We will focus our discussion on the low systemic immunological reaction, the effect of auto-skin islet, local immunological tolerance induced by in layed auto skin, the balance of Th1 and Th2 cells and the effects of some cytokines such as IL-10 in local immunological tolerance and etc. after intermingled transplantation.

[Effect of recombinant human granulocyte-macrophage colony stimulating factor on wound healing in patients with deep partial thickness burn].

OBJECTIVE: To evaluate the efficacy and safety of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) hydrogel in wound healing in patients with deep partial thickness burn. METHODS: The study was a multicenter, randomized, double-blind, placebo-controlled parallel clinical trial. Three hundred and twenty-one patients (302 cases finally fulfilled the protocol) with deep partial thickness burn were divided into A group (n = 200, with treatment of rhGM-CSF hydrogel, 100 microg/10 g/100 cm2/d), C group (n = 102,with treatment of placebo). Side-effect, systemic condition, wound healing time, wound healing rate, and total effective rate at different time points were observed. RESULTS: There were no obvious differences in vital signs, wound secretion, wound edge reaction, blood and urine routine, liver and kidney function between two groups (P > 0.05). No side-effect was observed. The median wound healing time was 17 days in A group, which was obviously shorter than that in C group (20 days, P < 0.01). The mean wound healing rate in A group was 24.5%, 70.5%, 95.3%, 99.6% respectively on 8th, 14th, 20th, 28th day after treatment, which were obviously higher than that in C group (15.1%, 51.4%, 84.6%, 97.1%, respectively, P < 0.01). The total effective rates in A group on 8th, 14th, 20th day after treatment were also higher than that in C group (P < 0.01). CONCLUSION: rhGM-CSF hydrogel can significantly accelerate wound healing in patients with deep partial thickness burn with certain safety.

[Study of neovascularization disturbance in deep partial-thickness scald in rats with diabetes mellitus].

OBJECTIVE: To study the relationship between the degree of neovascularization and non-healing wounds in scalded rats with diabetic mellitus. METHODS: Sixty Sprague-Dawley rats were randomly divided into control group (C, n = 30, with treatment of isotonic saline) and streptozocin (STZ)-induced diabetic group (D, n = 30, with treatment of STZ), and then they were inflicted with 20% TBSA deep partial thickness scald. Wound specimens were harvested immediately after scald and on 1, 3, 7, 10, 14, 21 post scald days (PSD) to observe histological changes, and wound healing rates were calculated. Degree of neovascularization in wound (labeled with blue microsphere) and the quantity of vascular endothelial cells (labeled with red CD31) were also measured by double-labeling immunofluorescence. RESULTS: Compared with those in C group, Wound healing rate and histological value scores were lowered, and the degree of neovascularization was abated markedly at each time point. The degree of neovascularization in D group (12.00 +/- 1.40) was obviously lower than that in C group on 7 PSD (60.00 +/- 3.00, P <0.01). There was no obvious difference in the number of vascular endothelial cells in both groups, however, the majority of endothelial cells had not formed functional capillaries in D group. CONCLUSION: Vascular endothelial cell can proliferate actively with poor blood supply in diabetic nonhealing with deep partial-thickness scald wounds, but it is still poor in blood supply due to lack of functional capillaries.

[Multi-center clinical study of the effect of silver nitrate ointment on the partial-thickness burn wounds].

OBJECTIVE: To evaluate the therapeutic effect of silver nitrate ointment on partial-thickness burn wounds, and observe its side-effects. METHODS: Multi-center, randomized, positive drug paralleled self-controlled trial was carried out. Eighty patients with superficial partial-thickness burns, and 40 with deep-partial thickness burns were randomized into AgNO3 group and SD-Ag group according to drug topically applied to the wounds. The wound healing time, wound healing rate and bacterial culture of the wound, the effect and safety of the drug, as well as drug irritation to the wounds were studied in these two groups. RESULTS: For the patients with superficial partial-thickness burn wounds, the wound healing time in silver nitrate group was (9.5 +/- 2.7) days, which was obviously shorter than that in SD-Ag group [(10.8 +/- 3.4) days, P <0.01]. The wound healing rate in silver nitrate group on 7 post-burn day ( PBD) was (77.9 +/- 20.5)%, which was obviously higher than that in SD-Ag group [(67.3 +/- 22.6) %, P < 0.01]. For those with deep-partial thickness burn wounds, the wound healing time in silver nitrate group was (21.5 +/- 4.8) days, which was evidently shorter than that in SD-Ag group [(23.3 +/- 6.4) days, P <0.01]. The wound healing rate in silver nitrate group on 20 PBD was (86.6 +/- 15.9)%, which was evidently higher than that in SD-Ag group [(78.5 +/- 17.7)%, P < 0.01]. Silver nitrate ointment has the same antibacterial effect as 1% SD-Ag cream, but it was less painful when applied to the open wounds. CONCLUSION: Silver nitrate ointment is an effective and safe medicament for the clinical management of partial-thickness burn wounds.

[Analysis of the influence on the prognosis and safety of arginine in patients with severe trauma and burns--a multi-center randomized double blinded, placebo controlled, clinical trail in 86 patients].

OBJECTIVE: To observe the influence on prognosis and possible side-effects of arginine in METHODS: Multi-center clinical trial, randomized double blinded patients with severe trauma and burns. and placebo control methods were employed in the study. Eighty-six patients with severe trauma and burns were randomly divided into control (C, n = 45) and arginine treatment (Arg, n = 41) groups. The patients in Arg group received arginine in dose of 0. 4 g x kg(-1) x d(-1) orally, while those in C group received same dose of placebo (tyrosine) for 7 days. All the patients in both groups were given diet with equal calories and equal nitrogen content. The changes in the wound healing time, hospital stay, and the incidence of side-effects of the medication in both groups of patients were observed and compared before and after the supplementation of arginine. RESULTS: The wound healing time and hospital stay days of severe trauma patient in Arg group (n = 29) were 11. 1+/-2. 8 d and 19+/-6 d, which were all obviously shorter than those in C group (13. 2+/-5. 5 d, 22 +/-6 d, n =33, P <0.05). On the other hand, in severe burn patients there were no significant difference of the wound healing time (20+/-5 d vs 22+/-8 d, n = 12, P > 0. 05) and hospital stay days (28+/-6 d vs 29+/-8 d, n = 12, P >0. 05) between the Arg and C groups. In addition, in C and Arg groups, the occurrence of the side-effects were seldom (2. 44% vs 2. 22% , P = 1. 000) and it disappeared when the supplementation of drugs was stopped. CONCLUSION: Oral feeding of arginine is beneficial in enhancing wound healing, reduction of hospital stay days in severe trauma patients and with little side-effects, but it is not beneficial to improve the prognosis of severe burn patients. Maybe this is due to inadequate number of case involved in the study.

[Multi-center clinical study of acticoat (nanocrystalline silver dressing) for the management of residual burn wounds].

OBJECTIVE: To investigate the clinical efficacy and safety of Acticoat (nanocrystalline silver dressing) for the treatment of residual burn wounds. METHODS: Ninety-eight patients with 166 residual burn wounds were enrolled in the multi-center randomized clinical trials. In addition to the routine treatment, Acticoat was applied onto the wounds of the trial group once a day if there was much exudation from the wound, or the dressing change was made every other two days when the wounds were clean. Silver sulfadiazine (SD-Ag) was used in the control group of patients. The healing time was observed up to 20 days. The healing rate on the 15th day after treatment was taken as the percentage of healing. RESULTS: The average healing time was (12 +/- 5) days after the application of Acticoat, which was significantly shorter than that in control wounds with SD-Ag (16 +/- 6) days, (P = 0.005 < 0.01). The total effective rate of the wounds for trial was 97.05%, which was higher than that in control (94.17%) group, but there was no statistically significant difference. The bacterial clearing rate of the Acticoat group on the 6th and 12th post treatment day was 21.7% and 43.5% respectively, which was significantly higher than that in control group. No side-effect was observed in the two groups during the study. CONCLUSION: Acticoat with nanocrystalline silver can promote the healing of residual burn wounds effectively.

[The biological characteristics of dermal fibroblasts of the diabetic rats with deep-partial thickness scald].

OBJECTIVE: To investigate the biological characteristics of dermal fibroblasts of the diabetic rats with deep partial thickness scald, and to explore its relationship with delayed wound healing due to diabetes. METHODS: Sprague-Dawley rats weighing 250 g were randomly divided into control (NM, n=40) and STZ-induced diabetic (DM, n=50) groups, and then deep partial thickness scald involving 10% TBSA were reproduced in the two groups. Skin samples were harvested from the wounds on 0, 3, 7, 14 and 21 post scald day (PSD) for the determination of certain histological characteristics. RESULTS: The thickness of dermis layer in DM group before injury was obviously thinner than that in NM group (P < 0.01). There was an infiltration of a large amount of chronic inflammatory cells and increased content of cutaneous glucose in the dermal tissue in DM group (2.77 mg/g) compared with 0.85 mg/g in NM group, (P < 0.01). An accumulation of advanced glycation end products (AGEs) was found in the dermal tissue in DM group. After the scalding, the percentage of fibroblasts in S phase and hydroxyproline synthesis in DM group was evidently lower than those in NM group. But the apoptosis rate of fibroblasts was much higher in DM group than that in NM group (P < 0.05 or 0.01). CONCLUSION: It is found that the high contents of glucose and AGEs in diabetic skin exert untoward effects on biological characteristics of dermal fibroblast, probably constituting one of the underlying mechanisms of delay wound healing of scald in diabetic rats.

[Bio-inductive effects of inorganic elements on skin wound healing].

OBJECTIVE: To explore the bio-inductive effects of inorganic elements (Dermlin) on the human epithelial proliferation and differentiation and their promoting effects on skin wound healing. METHODS: 1 ). Cellular test: Normal human skin epithelial cells were cultured with 20 g/L Dermlin supplemented culture medium (E group) and regular culture medium (C group), respectively. The cell proliferation rate and the expressions of type IV collagen and epidermal growth factor (EGF) in the supernatant were determined in 12 and 20 post culture days (PCD). (2). Animal test: Self-consubstantiality control was employed in the study. Sixty Sprague - Dawley rats were inflicted with two symmetric 10% TBSA of superficial or deep partial thickness scald on the back of each rat, and were divided into control[ C, with topical application of silver sulfadiazine (SD - Ag) cream to the wounds] and treatment (T, with 1 g/100 cm2 Dermlin topical application to the wounds) groups. The pathological changes in wound skin were observed and the wound healing rate was calculated on 3, 5, 7, 10, 14 and 18 post treatment day (PTD). (3). Randomized, double-blinded and consubstantiality control method was employed in the clinical trial. Ninety patients were enrolled in the clinical study, among them 30 cases with 60 donor site wounds, 30 with 60 superficial and 30 with 60 deep partial thickness burn wounds were included. Dermlin in dose of 1 g/100 cm2 was applied to the wounds in T group and SD - Ag cream in C group for up to 18 days. Furthermore, sixty patients with diabetic foot ulcers were included for 1 g/100 cm2 Dermlin treatment. The wound healing rate was observed. And the blood and urine test and the indices of hepatic and renal function were determined. RESULTS: 1). Cellular test: The cell proliferation rate and the expression of type IV collagen and EGF in the culture supernatant were obviously higher than those in control group at the same time points (P < 0.01). 2). Animal test: Hyperplastic granulation tissue occurred in the rat wound in the T group since 5 PTD, while that occurred in the C group since 7 PTD. The healing rate of superficial thickness wound in T group on 7, 10, 14 PTD, and that of deep partial thickness wound in T group on 5, 10, 18 PTD were obviously higher than that in the C group (P <0.05). 3). Clinical study indicated that the wound healing rate of the patients with superficial or deep partial thickness scald in the T group was evidently higher than that in the C group on 5 and 10 PTD (P <0.05), but the wound healing time of the superficial, deep partial thickness wound and donor site wound in the T group was significantly shorter than that in the C group (P < 0.05). Before treatment, the square of the ulcers on the foot of the patients with diabetic was (39 +/- 28) cm2, and it was reduced to (19 +/- 23) cm2 2 weeks later, with the therapeutic efficacy reaching 62.5% . For all patients, no obvious change was found in the blood test and hepatic and renal function indices. CONCLUSION: The inorganic element (Dermlin) is beneficial to wound healing and to the proliferation and differentiation of epithelial cells.

[The influence of dermal template on the expressions of signal transduction protein Smad 3 and transforming growth factor beta1 and its receptor during wound healing process in patients with deep burns].

OBJECTIVE: To investigate the influence of dermal template on the expressions of signal transduction protein Smad 3 and transforming growth factor beta1 and its receptor during wound healing process in patients with deep burns. METHODS: Twenty burn patients with excision of full thickness burn in the extremities were enrolled in the study and divided into two groups, i.e. template interfering group (E, n = 20, grafting of dermal template [allogeneic acellular dermal matrix] with razor thin autoskin) and control group (C, n = 20, grafting of razor thin autoskin only). The contralateral side served as the self-control. Tissue samples from the burn wounds were harvested at 1, 2, 3 and 4 post-operative weeks (POW) for immunohistochemistry staining. The positive expression rates of TGF-beta1, TbetaRI, TbetaRII and Smad3 proteins were determined by image analysis system. RESULTS: The positive expressions of TGFbeta1, TbetaRI, TbetaRII and signal transduction protein Smad 3 in the tissue samples in both groups could be identified during 1 approximately 4 POW, and they diminished thereafter with the process of wound healing. The expression rate of TGF-beta1 in E group was (13.08 +/- 4.65)% at 1 POW and (9.03 +/- 1.89)% at 4 POW. The positive expression rate of above indices in E group was obviously lower than that in C group in corresponding time points (P < 0.05). CONCLUSION: The expression levels of TGFbeta1, TbetaRI, TbetaRII and Smad 3 protein in deep burn wounds could be lowered by mixed grafting of dermal template with razor thin autoskin, which might be beneficial in ameliorating of scar hyperplasia in the burn wound.

[Influence of tangential excision within 24 postburn hours on the local wound inflammatory response in patients with deep partial thickness burn].

OBJECTIVE: To investigate the influence of early tangential excision within 24 postburn hours on local wound inflammatory response and tissue injury in patients with deep partial thickness burn. METHODS: Twelve patients with deep partial thickness burn were enrolled in the study. Tangential excision was performed within 24 postburn hours. The same wound of a patient was divided into three areas for harvesting tissue samples, i.e. pre-operation, post-operation and non-operation areas. For each patient, the biopsies from the pre-operation area were harvested before tangential excision, while those from post-operation and non-operation areas were harvested during 5 to 7 postburn days (PBDs). The contents of IL-8, MPO and MDA in wound tissue were determined by tissue culture and chemical colorimetry, respectively. HE and Mason's staining were employed to assess the degree of necrosis of the wound tissue. RESULTS: The IL-8, MPO and MDA contents in the local wound tissue after tangential excision were 6.83 +/- 1.85 microg/L, 4.07 +/- 0.87 U/g, and 8.94 +/- 5.66 micromol/g, respectively, which were significantly lower than those from non-operation area (P < 0.01). The inflammatory response in the non-operative wound area was distinct with expansion of necrotic tissue area. In contrast, the local inflammatory response of the wound after tangential excision was ameliorated without the enlargement of necrotic tissue area. CONCLUSION: Tangential excision within 24 postburn hours could be beneficial in ameliorating local inflammatory response, and in preventing progressive deepening of the burn wounds, thus it could accelerate wound healing in patients with deep partial thickness burn.

[Influence of dermal template on the biomechanical compliance of wound tissue].

OBJECTIVE: To investigate the influence of dermal template on the biomechanical compliance of wound tissue during wound repair. METHODS: One hundred and forty-four SD rats subjected to full-thickness skin loss on the dorsum were enrolled in the study, and they were randomly divided into A (n = 6, without grafting on wound), B (n = 6, with full thickness skin grafting on wound), C (n = 6, with razor thin skin grafting on wound) and D [n = 6, with acellular dermal matrix (ADM) and razor thin skin grafting on wound] groups. The tissue samples from the wounds were harvested 1, 2, 4, 6, 12 and 20 weeks after the operation. The biomechanical compliance of the wound was assessed by Instron biomechanics tensiometer. The expression of alpha-SMA in the dermal fibroblasts of each group was determined by immunohistochemistry (ABC) method. RESULTS: The biomechanical compliance of the wound in D group was higher than that in A and C groups (P < 0.05), but lower than that in B group during 4 to 20 weeks after operation (P < 0.05). The expression of alpha-SMA in D group (7.53 +/- 0.98)% was lower than that in A (26.99 +/- 2.90)% and C (2.18 +/- 2.79)% groups (P < 0.01), but higher than that in B group at 4 weeks after operation (P < 0.05). CONCLUSION: Dermal template might affect the scar formation during wound healing, in improving wound healing quality by enhancing the biomechanical compliance of wound tissue.

[Investigation on the drug resistance of Pseudomonas aeruginosa in our burn ward in the past 11 years].

OBJECTIVE: To analyze the use of antibiotics and the drug resistance of Pseudomonas aeruginosa in the burn ward of our hospital in the past 11 years, so as to optimize the use of antibiotics in the future. METHODS: Bacterial epidemiology during 1991-2001 in our burn ward was investigated. The change of the drug resistance of Pseudomonas aeruginosa was observed by defined daily dose (DDD) of antibiotics in adult patients and by the ranking of antibiotic administration days. RESULTS: (1) Staphylococcus aureus (10.53%-34.40%) and Pseudomonas aeruginosa (75.66%-11.47%) were dominant in our burn ward. (2) Predominant antibiotics used included Penicillin, Amikacin, Vancomycin, Imipenem and Ceftazidime. (3) There was increasing drug resistance of Pseudomonas aeruginosa to the following antibiotics ranking in following order: Piperacillin (41.57%-100.00%), Imipenem (36.36%-98.46%), Ceftazidime (23.46%-97.85%), Amikacin (13.16%-100.00%) and ciprofloxacin (6.90%-100.00%). CONCLUSION: There was increasing drug resistance of Pseudomonas aeruginosa to all antibiotics, which might be related to antibiotic abuse.