Clinical characteristics and diagnosis of sepsis in pediatric burn patients / 中华烧伤杂志

Pediatric burn patients account for more than 1/3 of the inpatients in the same period, and its incidence surpasses that of burn patients in other age groups. However, it brings about much difficulty to treat pediatric burn patients complicated by sepsis, which brings a significantly higher mortality than that of the adult. Moreover, the physiological characteristics, development of organs, drug metabolism, and body response to burn injury in children are obviously different from those of the adult. Therefore, it is clinically important to understand the clinical characteristics of sepsis in pediatric burn patients in order to improve the diagnosis and treatment of this ailment.

Influence of infection of murine chemokine receptor-7 recombinant lentivirus on the immunogenicity and migration of DC 2.4 cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the influence of infection of murine chemokine receptor-7 recombinant lentivirus on the immunogenicity and migration of dendritic cell strain DC 2.4 cells.</p><p><b>METHODS</b>DC 2.4 cells were routinely cultured. Lentiviruses carrying GFP and those with up-regulated CCR7 were constructed. DC 2.4 cells were divided into DC 2.4 group (without any treatment), GFP-DC 2.4 group (infected with GFP-carrying lentivirus), and CCR7-DC 2.4 group (infected with CCR7-carrying lentivirus labeled by GFP) according to the random number table. The expressions of surface molecules MHCII, CD80, CD86, and CCR7 were detected by flow cytometry, Western blotting, and confocal laser scanning microscope. The migration of cells was detected by chemotaxis assay in vitro. The immunogenicity of cells was detected with mixed lymphocyte reaction. LPS-DC 2.4 group was set up as positive control. Data were processed with one-way analysis of variance and t test.</p><p><b>RESULTS</b>Lentiviruses carrying stably-expressing CCR7 were constructed, and the transfection rate of which into DC 2.4 cells was 87.4%. There was no statistically significant difference among DC 2.4, GFP-DC 2.4, and CCR7-DC 2.4 groups in the expressions of MHC II, CD80, and CD86 as showed by flow cytometry (with F values from 0.17 to 1.19, P values all above 0.05). The protein expression of CCR7 of cells in CCR7-DC 2.4 group (45.1 ± 2.1) was obviously higher than that in DC 2.4 and GFP-DC 2.4 groups (25.3 ± 1.4, 28.6 ± 0.9, F = 162.90, P < 0.01), while the difference of which between DC 2.4 group and GFP-DC 2.4 group was not statistically significant (t = 2.20,P > 0.05). The fluorescence intensity of CCR7 in CCR7-DC 2.4 group was obviously increased compared with that of DC 2.4 group. The chemotaxis migration rate of cells in CCR7-DC 2.4 group with the influence of CCL19 was (41.0 ± 2.0)%, which was significantly higher than that of DC 2.4 and GFP-DC 2.4 groups [(6.0 ± 0.5)%, (6.8 ± 0.3)%, F = 84.21, P < 0.01]. There was no statistically significant difference between DC 2.4 group and GFP-DC 2.4 group in the migration rate (t = 0.45, P > 0.05). The absorbance values in DC 2.4, GFP-DC 2.4, CCR7-DC 2.4, and LPS-DC 2.4 groups were respectively 1.6 ± 0.4, 1.9 ± 0.4, 1.7 ± 0.4, 3.8 ± 0.4, and the differences among the former three groups were not obvious (F = 1.56, P > 0.05). The absorbance value in LPS-DC 2.4 group was obviously higher than that of the other three groups (with t values from 1.53 to 1.82, P values all below 0.01).</p><p><b>CONCLUSIONS</b>DC 2.4 cells infected with efficiently CCR7-expressing lentivirus showed high chemotaxis to CCL19, but without obvious change in immunogenicity.</p>

A propose to suspend the use of hydroxyethyl starch for fluid resuscitation in shock phase of severe burns / 中华烧伤杂志

Based on the result of randomized controlled trials and meta-analysis recently, the infusion of hydroxyethyl starch (HES) was not shown to over match routine crystalline solution in exerting resuscitation effect against hypovolemia of patients with burn shock, severe systematic infection, or other critical conditions, on the other hand, it may induce renal toxicity and other toxic and side effects. Since the pathological mechanism underlying hypovolemia during shock phase after burn is similar to that of severe systemic infection, we propose to suspend the use of HES for fluid resuscitation during the shock phase of severe burn until further elucidation.

Comparative study on the effect of restrictive fluid management strategy on the early pulmonary function of patients with severe burn / 中华烧伤杂志

<p><b>OBJECTIVE</b>To retrospectively analyze the effect of restrictive fluid management strategy (RFMS) on the early pulmonary function and the prognosis of patients with extremely severe and extensive burn.</p><p><b>METHODS</b>Thirteen patients with extremely severe burn hospitalized from June 2010 to November 2011, being treated with RFMS in the fluid reabsorption stage, were enrolled as treatment group. Twenty-six patients with extremely severe burn hospitalized from March 2008 to November 2011, being treated with normal fluid therapy in the fluid reabsorption stage, were enrolled as control group. The match proportion between treatment group and control group was 1:2. Fluid intake, fluid output, fluid balance (the difference between fluid intake and output), and plasma albumin level from post burn day (PBD) 3 to 10, pulmonary oxygenation index on PBD 3, 5, 7, 10, and 14, occurrence of lung and blood stream infections from PBD 7 to 14, and occurrence of acute respiratory distress syndrome (ARDS), occurrence of other organ complications, and mortality within 2 weeks post burn (PBW) were recorded and compared. Measurement data were processed with t test and randomized blocks analysis of variance, enumeration data were processed with Fisher's exact test.</p><p><b>RESULTS</b>Daily fluid intake of patients showed a tendency of decrease in both groups from PBD 3 to 10. Except for that of PBD 4, there was no statistically significant difference between two groups in fluid intake (with F values from 0.072 to 1.939, P values all above 0.05). Daily fluid output of patients showed a tendency of increase in both groups from PBD 3 to 10. It peaked on PBD 10 in control group and PBD 6 in treatment group. The mean daily fluid output was higher in treatment group than in control group from PBD 4 to 9, but without statistically significant difference (with F values from 0.001 to 3.026, P values all above 0.05). Fluid balance lowered in both groups, and it was the lowest on PBD 10 in control group and PBD 6 in treatment group. Fluid balance was lower in treatment group than in control group from PBD 3 to 7, and it showed statistically significant differences on PBD 4, 5, and 6 (with F values from 4.799 to 8.031, P values below 0.05). Plasma albumin level was higher in treatment group than in control group from PBD 3 to 10, with statistically significant differences observed on PBD 4, 9, and 10 (with F values from 5.691 to 10.551, P < 0.05 or P < 0.01). Pulmonary oxygenation index was higher in treatment group than in control group from PBD 3 to 14, with statistically significant differences observed on PBD 7 (respectively 372 ± 78 in treatment group and 291 ± 92 in control group, F = 5.184, P < 0.05) and 14 (respectively 354 ± 39 in treatment group and 283 ± 72 in control group, F = 8.683, P < 0.05). Lung infection and blood stream infection were respectively observed in 1 and 4 patient (s) in treatment group, and 9 and 11 patients in control group from PBD 7 to 14. Occurrence of ARDS, occurrence of other organ complications, and mortality were fewer in treatment group than in control group within PBW 2, though the differences were not statistically significant (P values all above 0.05).</p><p><b>CONCLUSIONS</b>RFMS is a useful strategy in improving early pulmonary oxygenation of patients with extremely severe and extensive burn by promoting the process of fluid reabsorption and rebalance. This strategy may be also beneficial for the prevention of organ complications as well as a better prognosis in severely burned patients.</p>

Reproduction of a rat model of burn with infection / 中华烧伤杂志

<p><b>OBJECTIVE</b>To reproduce a reliable rat model of burn with infection for the study of prevention and treatment of infected wound.</p><p><b>METHODS</b>(1) Electrical burn producing apparatus equipped with constant temperature (80°C) and pressure (0.5 kg) was used to reproduce burn injury (with area of 4.5 cm(2)) on both sides of the back in 50 SD rats for different duration (4, 6, 8, 10, 12 s), with 10 rats for each burn duration. On post burn day (PBD) 1, gross condition of wounds was observed with naked eyes. Wounds on the left side were used to observe healing time. The wounds on the right side were used for histological observation to determine the depth of injury, and they were classified into superficial and deep partial-thickness injury. (2) Another 36 SD rats were divided into A (inflicted with superficial partial-thickness burn, n = 18) and B (inflicted with deep partial-thickness burn, n = 18) groups according to the random number table. Rats in both groups were treated in accordance with method of preliminary experiment. Immediately after burn, 0.1 mL of liquid containing 1 × 10(9), 1 × 10(7), 1 × 10(5) CFU Pseudomonas aeruginosa (PA) ATCC 27853 was respectively inoculated to the wounds on one side (with 6 rats for each amount), while the wounds on the other side were treated with the same volume of normal saline as control. Inflammatory reaction of wounds was examined with HE staining on post inoculation day (PID) 1. On PID 1, 2, 3, 5, 7, and 14, the number of subeschar bacteria was respectively counted and the bacteria were identified with Gram stain and biochemical reaction. Wound healing time was recorded. Data were processed with t test.</p><p><b>RESULTS</b>(1) Burn for 6, 8 s was respectively identified as injury time resulting in superficial or deep partial-thickness injury according to histological observation and wound healing time. (2) Obvious inflammatory cell infiltration was observed in the wounds in B group which were inoculated with 1 × 10(7), 1 × 10(9) CFU PA, and the infiltration was less marked in A group with inoculation of 1 × 10(9) CFU PA. (3) The bacteria isolated from wounds of A and B groups was identified as PA. The subeschar bacteria count within PID 14 in A group, in which different amount of PA was inoculated, was mostly less than 1 × 10(5) CFU/g of tissue, while that in B group in which 1 × 10(9) CFU PA was inoculated was more than 1 × 10(5) CFU/g of tissue. (4) There was no obvious difference in wound healing time between wounds inoculated with different amount of PA and wounds treated with normal saline in A group (with t value respectively 1.26, 0.29, 1.07, P values all above 0.05). Wound healing time of wounds in B group, in which 1 × 10(9) CFU PA was inoculated, was longer as compared with that treated with normal saline [(22.5 ± 1.0) d vs. (19.4 ± 1.6) d, t = 2.73, P < 0.05].</p><p><b>CONCLUSIONS</b>In rat, deep partial-thickness burn wound inoculated with 1 × 10(9) CFU PA ATCC 27853 is a reliable model with high reproducibility for the study of infection of burn wound.</p>

Clinical assessment of colistin in treating infections caused by multidrug-resistant gram-negative bacillus in patients with severe burn / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the therapeutic effect and side effects of colistin in treating infections caused by multidrug-resistant (MDR) gram-negative bacillus in patients with severe burn in order to provide the basis for reasonable application of this antibiotic in clinic.</p><p><b>METHODS</b>Nine burn patients suffered from infections caused by MDR gram-negative bacillus admitted to our institute from August 2005 to January 2009 were involved in this study. On the premises that isolated bacteria were only sensitive to colistin or not sensitive to other antibiotics, patients were treated with intravenous drip of colistin (100 x 10(4) - 150 x 10(4) U/d), or intravenous drip combined with administration of the drug into respiratory tract by atomization or instillation (50 x 10(4) - 100 x 10(4) U/d). The bacteriologic and therapeutic effects and side effects (including neurotoxicity and nephrotoxicity, rise in serum levels of creatinine, urea nitrogen and cystatin C were detected and compared before and after administration) of colistin were observed.</p><p><b>RESULTS</b>Out of 9 patients, 7 patients were with bloodstream and pulmonary infections, 1 patient was with bloodstream, pulmonary, and invasive wound infections, and 1 patient was with bloodstream and urinary tract infections. The pathogenic bacteria were proved to be Pseudomonas aeruginosa, Acinetobacter baumannii and Pseudomonas maltophilia. After the administration of colistin, bacteria clearance rate of blood reached 92.3% in 9 patients; isolation rate of MDR gram-negative bacillus of sputum was significantly decreased in 7 patients with pulmonary infection (before treatment 58.2% v.s. after treatment 14.6%, P < 0.01); a complete MDR gram-negative bacillus clearance of urine was observed in 1 patient with urinary tract infection. Colistin was clinically effective in 8 patients but ineffective in 1 patient (effective rate 88.9%). Compared with those before administration, serum levels of creatinine and urea nitrogen were decreased after administration in all patients; no significant difference in serum level of cystatin C among 8 patients was detected, except an obvious elevation in serum level of cystatin C in 1 patient after colistin therapy, and it lowered 1 month after discontinuation. No neurotoxicity or other side effect was observed during medication and 5 days after discontinuation in all patients.</p><p><b>CONCLUSIONS</b>Reasonable application of colistin is a good option for treating infections caused by MDR gram-negative bacillus in patients with severe burn, as no other more effective drug is found.</p>

A clinical study of fungal infection in burn patients / 中华烧伤杂志

<p><b>OBJECTIVE</b>To address the features of the fungal infection after burn injury in clinic.</p><p><b>METHODS</b>Three thousand nine hundred and nine burn patients admitted to our institute from Jan. 2003 to Dec. 2006 were involved in this study. Two thousand two hundred and seventy-one samples were harvested for fungal detection by culture from 467 patients suspected to be infected by fungi based on their clinic manifestations. The collected samples included wound tissue, blood, urine, stool, sputum, catheters and others. The antibiotic sensitivity of the identified fungi were determined by routine method. When same kind of fungus was found from different samples taken from one patient, it was recorded as one positive sample. The samples were ranked in an ascending order as wound secretion, stool, urine, sputum and bronchial alveolar lavage fluid, arteriovenous catheter or urinary catheter, blood. Only the positive sample of the highest rank source was recorded as the positive strain of fungus from this particular patient.</p><p><b>RESULTS</b>It was found 61 fungal positive samples from the 2271 samples collected. Out of 467 patients, 38 strains of fungi were detected from 36 burn patients during the investigated period, the incidence was 0.92% (36/3909). The most three commonest types among the identified 38 strains of fungi were Candida tropicalis (42.1%), Candida albicans (31.6%) and Candida famata (T. Famata, 10.5%). The drug sensitivity tests demonstrated that most of the strains detected in this investigation, with the exception of candida glabrata, were sensitive to most of the routine antimycotics agents such as Amphotericin B, Fluconazole, and Itraconazole etc. Among the 36 fungus positive patients, in 18 patients the burn area exceeded 80% TBSA, 12 patients with 50%-79% TBSA, 4 patients with 30%-49% TBSA, and in 2 patients the burn area was smaller than 30% TBSA. It was found most of the fungal infections (77.78%) occurred 2 weeks after burn injury, and 8 of the 36 fungus-infected patients died (the mortality was 22.22%). Conclusions Further examinations are necessary to confirm the diagnosis in burn patients suspected to have fungal infection. Once fungal infections are confirmed, antimycotic therapy must be started immediately.</p>

Clinical study on the repair of extensive deep burn wounds with autogenous fat granules and autologous microskin grafts in mixed grafting / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the effects of autologous fat granules in mixed grafting microskin grafts on repair of extensive deep burn wounds in patients.</p><p><b>METHODS</b>Twenty patients hospitalized in our ward were enrolled for autogenous self-control test in wounds on both or symmetrical parts of wounds of the trunk, and they were randomly divided into experimental (E) trol (C) groups, the wounds in E group were repaired with autologous fat granules together with microskin in mixed grafting (volume ratio 1 : 1), and in C group only autologous microskin grafting was given. Wound healing rate was measured on 30th, 45th, and 60th day after operation. Wound specimens harvested for HE staining and PCNA immunohistochemistry examination on 7th, 14th, 21st, and after operation.</p><p><b>RESULTS</b>(1) The mean wound healing rate on 30th, 45th, and 60th day after E group was (56.3 +/- 3.1)%, (76.4 +/-6.1)%, (96.2 +/- 1.5)%, which were respectively higher C group [(28.3 +/-2.0)%, (47.3 +/-4.8)%, (85.4 +/- 2.2)%, P < 0.01]. HE staining showed epithelization in E group was earlier than that in C group, with regular arrangement of collagen fibers. The quantity NA positive cells in E group were larger than that in C group, and PCNA was mainly expressed cells of basal layer .</p><p><b>CONCLUSION</b>Autologous fat granules in mixed grafting with autologous microskin promote wound healing.</p>

Influence of HSP70 on function and energy metabolism of mitochondria in intestinal epithelial cells after hypoxia/reoxygenation / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effect of recombinant adenovirus-mediated heat shock protein 70 (HSP70) on energy metabolism of mitochondria in intestinal epithelial cells (IEC-6) after hypoxia/reoxygenation injury .</p><p><b>METHODS</b>IEC-6 cells were transfected with HSP70 recombinant adenovirus vectors (Ad-HSP70) and empty adenovirus vectors. The expression of HSP70 protein was detected by Western blotting. Cultured IEC-6 cells were divided into: control group (without treatment), hypoxia/reoxygenation group (with challenge of hypoxia/reoxygenation) and Ad-HSP70 transfection group (with challenge of hypoxia/reoxygenation after Ad-HSP70 transfection). The activity of mitochondrial dehydrogenase was assessed by MTf method. The contents of cellular ATP, ADP , AMP and energy charge (EC)were determined by high-performance liquid chromatography (HPLC).</p><p><b>RESULTS</b>The expression of HSP70 protein in IEC-6 cells was significantly upregulated after Ad-HSP70 transfection compared with empty adenovirus vector transfection. Compared with that in control group, the activity of mitochondrial dehydrogenase was significantly lowered in IEC-6 cells in hypoxia/reoxygenation group (P < 0.01). The activity of mitochondrial dehydrogenase in Ad-HSP70 transfection group was significantly greater than that in hypoxia/reoxygenation group (P < 0.01). Compared with those in control group,the content of cellular ATP was significantly decreased in hypoxia/reoxygenation group, the contents of cellular ADP and AMP were significantly increased. The above cell energy indices in Ad-HSP70 transfection group was similar to those in control group (P > 0.05), which were ameliorated compared with those in hypoxia/reoxygenation group (P < 0.050 or P < 0.01). The cellular EC in hypoxia/reoxygenation group (0.615 +/- 0.060) was significantly lower than that in control group (0.748 +/- 0.012, P < 0.01) and Ad-HSP70 transfection group (0.736 +/- 0.028, P < 0.01).</p><p><b>CONCLUSION</b>Ad-HSP70 transfection in IEC-6 cells can upregulate the expression of HSP70, the content of cellular ATP and EC after hypoxia/reoxygenation, and protect mitochondrial function. Mitochondria may be one of main target organelles for HSP70 in protection of IEC against hypoxia/reoxygenation injury.</p>

Clinical practice and evaluation of relative fluid resuscitation formula at burn shock stage / 中华烧伤杂志

<p><b>OBJECTIVE</b>To evaluate the application of the Third Military Medical University (TMMU) formula for fluid resuscitation on the major burn patients during shock stage.</p><p><b>METHODS</b>Seventy-one thermal injury patients (burn area more than 30% TBSA, without especial illness, hospitalization within 8 hour after burn) admitted from 2005 to 2007 were divided into adult group (n = 46), child group (n = 25). Fluid resuscitation was initiated as per the TMMU formula.</p><p><b>RESULTS</b>All patients survived the first 48 hours post burn injury and none developed recognized complications associated with fluid resuscitation. The average infused fluid was 16% approximately 38% more than the calculated in both adult and child groups. The average urine output during the first 24 hours post burn injury was 1.1 approximately 1.2 mL x kg(-1) x h(-1) in the two groups, but reached 1.2 mL and 1.7 mL x kg(-1) x h(-1) during the second 24 hours in adult and child groups respectively.</p><p><b>CONCLUSION</b>TMMU formula for fluid resuscitation is a feasible option for major burn patients. Individual fluid resuscitation, guided by the physiological response, is also important and necessary.</p>

Influence of heat shock protein 90 on protein serine threonine kinases expression in hypoxic cardiomyocytes / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the effect of endogenous heat shock protein 90 (HSP90) on the AKT signaling pathway of hypoxic cardiomyocytes.</p><p><b>METHODS</b>The hypoxia model of neonatal rat cardiomyocyte was established. The cells were randomly divided into normal control, hypoxia, Geldanamycin (GA, with hypoxia after Geldanamycin treatment) groups. The myocardial cell activity and the expression of endogenous HSP90 and AKT were determined with MTT and Western blotting, respectively at 1, 3, 6, 12, 24 and 48 post-hypoxia hours (PHH). The apoptotic index (AI) of cardiomyocytes were determined with TUNEL method at 24 PHH.</p><p><b>RESULTS</b>(1) At 24 and 48 PHH, the activity of cardiomyocytes in hypoxia group and GA group were evidently lower than that in control group (P < 0.05). The activity of cardiomyocyte in GA group began to decrease at 12 PHH, and it was obviously lower than that in hypoxia group at 48 PHH (P < 0.05). (2) At 24 PHH, the AI in hypoxia group (10.7 +/- 1.2)% was obviously higher than that in normal control group [(1.9 +/- 0.3)%, P < 0.05], while it was obviously lower than that in GA group [(26.3 +/- 5.3)%, P < 0.01]. (3) The expression of endogenous HSP90 and AKT in hypoxia and GA groups were markedly increased compared with that of normal controls at 12 PHH, and it decreased at 24 PHH in hypoxia and GA groups, especially in the latter.</p><p><b>CONCLUSION</b>Endogenous HSP90 plays important roles in maintaining the cardiomyocyte activity, and its level might affect the expression of AKT.</p>

Standardized definitions and diagnostic criteria for infection in burn patients / 中华烧伤杂志

There are many criteria for the diagnosis of infection and sepsis in most patients, but the standardized definitions for infection and sepsis in burn patients are less applicable to the burn population and have never been developed. We recommend that suspicious systemic infection (sepsis) should be considered as a clinical syndrome defined by the presence of signs and symptoms of systemic infection even with negative blood microbial culture, systemic infection should be identified with positive blood microbial culture or clinical response to antimicrobials. We also expand the list of diagnostic criteria for systemic infection to reflect clinical experience in burn patients. Further refinement will be necessary when these definitions are considered for routine application in clinical practice.

Study on the induction of skin transplantation tolerance against rejection in mice by third-party dendritic cells loaded with donor's antigens / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate whether the third-party dendritic cells (DC) incubated with donor's antigens possess the similar immune functions with donor derived immature DC.</p><p><b>METHODS</b>Female C57 BL/6, BALB/c and Kunming mice were used as skin transplant donors, recipients and third-party, respectively. Forty BALB/c mice were randomly divided into A (normal control), B (cyclophosphamide administration), C (CTX and donor derived immature DC), D (CTX and third-party immature DC), E (CTX and third-party DC loaded with donor's antigens) groups, with 8 mice in each group. The mice in group B, C, D and E were given CTX (200 mg/Kg) 4 days before operation, while those in group A were given equivalent amount of normal saline(NS). Then in group C, D and E, DC at a dose of 1 x 10(7)/ml were intraperitoneally injected with 2 days before grafting and 12 days after operation, but the mice in group A and B were given NS in the same manner. Mean survival time (MST) of skin grafts was recorded, and biopsies of grafts on 5 and 10 post-operation days (POD) were harvested for histologic examination.</p><p><b>RESULTS</b>Compared with group A [(16.1 +/- 3.5)d], MST of skin grafts in group C [(38.3 +/- 7.7) d] and E [(34.9 +/- 7.7) d] were significantly prolonged ( P < 0.01), while no obvious difference was observed between group C and E( P > 0.05), but there was statistically significant difference in MST between group D [(23.7 +/- 2.7) d] and E ( P < 0.05). In addition, clear epithelial structure and infiltration of inflammatory cells were observed in specimens from both groups C and E.</p><p><b>CONCLUSION</b>Both donor derived immature DC and third-party DC loaded with donor's antigens can partly induce donor specific transplantation tolerance.</p>

Multi-center clinical study of acticoat (nanocrystalline silver dressing) for the management of residual burn wounds / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the clinical efficacy and safety of Acticoat (nanocrystalline silver dressing) for the treatment of residual burn wounds.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>Acticoat with nanocrystalline silver can promote the healing of residual burn wounds effectively.</p>

Influence of liposome induced gene transfection on the characteristics of human immature dendritic cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of liposome induced gene transfection on the phenotypic characteristics and immune function of human immature dedritic cells (imDC).</p><p><b>METHODS</b>Monocytes were isolated from human cord blood, and they were differentiated into imDC by rhGM-CSF and rhIL-4 induction. Then the morphologic observation and immune phenotypic identification were performed in im-DCs. imDCs were divided into transfection (T, with liposome transfection of pEGFP vector) and control (C, without transfection) groups. The transfection rate and expression of cell maturation marker (CD83, CD86 and HLA-DR) were determined with flow cytometry, and the proliferation of non-sensitized T lymphocyte before and after transfection was determined with allogeneic mixed leukocyte reaction (MLR).</p><p><b>RESULTS</b>im-DC derived from human cord blood cells had typical appearance and surface markers consistent to what reported in the literature. The expression rates of CD86, CD83 and LA-DR in T group were (12 +/- 6) %, (8.6 +/- 2.3) % and (71 +/- 7) %, respectively, which exhibited no difference compared with those in C group (13 +/- 6) %, (9.1 +/- 3.8) % and (72 +/- 8) %, (P > 0.05). MLR results indicated that there was no obvious change in the immune stimulation function of imDC after transfection (P > 0.05) , with stimulation index lower than 2.</p><p><b>CONCLUSION</b>There is no change in maturation of imDC after liposome transfection, but the transfection efficiency needs to be elevated.</p>

The influence of antigen loading on the immunological characteristics of dendritic cells induced by low concentrations of granulocyte macrophage colony stimulating factor / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of low doses of granulocyte macrophage colony stimulating factor on the allogeneic antigen (Ag) ingestion capacity of immature dendritic cells (GM low DC), and subsequently the changes in the cellular phenotype and function.</p><p><b>METHODS</b>Mononuclear cells from C57BL/6 mice was labelled with 3H-Leu to make Ag supernatant. The Ag supernatant was cocultured with GM low DC or mature DC for 30,60 and 90 mins, then cpm value were determined. The changes in I(A)/I(E) and CD80 on cell surface after antigen ingestion were determined with flow cytometry (FCM). By using mixed lymphocyte reaction (MLR), the cells were divided into control (non-sensitized T lymphocyte), GM low DC, GM low DC and allogeneic antigen, GM low DC and allogeneic antigen and CTLA-4 Ig groups. The cpm value in each group was recorded and the stimulation index (SI) was calculated.</p><p><b>RESULTS</b>Upon 30, 60 and 90 mins of allogeneic Ag stimulation, the cpm value of GM low DC was obviously higher than that of mature DC (P < 0.05 or 0.01). In addition, the expression of I(A)/I(E) and CD80 before allogeneic Ag ingestion were significantly higher than those after Ag ingestion (I(A)/I(E): 32 +/- 8% vs. 54 +/- 10, P < 0.05; CD80: 25 +/- 10% vs. 71 +/- 18%, P < 0.01). MLR: Compared with control group, the cpm value in GM low DC with allogeneic Ag group was increased markedly (P < 0.05), with SI higher than 2.0, while no difference was found among control, GM low DC group, GM low DC and allogeneic Ag and CTLA-4Ig groups (P > 0.05), with SI lower than 2.0</p><p><b>CONCLUSION</b>Though GM low DC exhibits powerful antigen ingestion capacity, the cell phenotype and function will get mature gradually. Immune tolerance can be established by incubating GM low DC with CTLA-4Ig.</p>

Experimental study on cryopreservation of immature dendritic cells derived from cord blood / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the biological properties of immature dendritic cells( imDC) derived from cord blood before and after cryopreservation, so as to provide a method for preservation of imDC.</p><p><b>METHODS</b>Immature dendritic cells were generated from human cord blood (CB) monocytes and cultured with rhGM-CSF and rhIL-4, and 10% DMSO was added into culture medium as cryopreservation reagent. After freezing in - 80 degrees C refrigerator, the cells were finally cryopreserved in - 196 degrees C liquid nitrogen, and then thawed with 40 'C water, and they were finally named frozen-thawed imDC. The morphology of imDC were observed with light microscope, and TBR were calculated. Cellular surface markers for DC maturation were determined with flow cytometry, and the ability of the cells to stimulate proliferation of non-sensitized T lymphocyte was determined with allogeneic mixed lymphocyte reaction.</p><p><b>RESULTS</b>Monocyte (MNC) from cord blood could differentiate into DC after GM-CSF and rhIL-4 induction. Under light microscope, the cells showed irregular morphology, with branch-like prominence on the cell surface. Similar changes were also observed with scan electron microscope. The cryopreserved imDC were resistant to trypan blue staining, and TBR was (86. 8 +/- 1. 3) % . There was no obvious difference in the cell morphology between cryopreserved and fresh imDCs. The expression of cell surface markers and maturation markers in imDCs before cryopreservation were as follows: CDla(62 +/-8)% , CD14 (18 +/- 7)% , HLA-DR (67 +/- 5)% , CD80 (13+/-7)%, CD 86 (12+/- 5) % . Though the expression of CD80, CD86 and CD83 of cryopreserved imDC increased to (15 +/-5)% , (17 +/-5)% and (7.4 +/-3. 3)% , respectively( P <0.05), they still possessed the phenotype of imDC. There exhibited no obvious difference in cmp value between fresh imDC[ (463 +/- 104) min(-1) ] and cryopreserved imDC[ (512 +/-78 )min(-1) ] , ( P > 0. 05 ). The cpm in control group was (488 +/- 197 ) min'. The stimulation index in all groups was lower than 2, and both fresh imDC and cryopreserved imDC could not stimulate the proliferation of non-sensitized T lymphocyte.</p><p><b>CONCLUSION</b>The cryopreserved imDC exhibits immature characteristic in cell phenotypes, function and good cell activity, indicating that the method of cryopreservation of imDC is feasible.</p>

Influence of adenovirus transfection on the maturation characteristics of human immature dendritic cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the changes in the phenotype characteristics and immune function after transfection of cord blood derived immature dendritic cells( imDC) with Adeasy-EGFP adenovirus vector, and to explore the function of IL-10 in inhibition of imDC maturation.</p><p><b>METHODS</b>Immature dendritic cells were generated from human cord blood(CB) monocyte cultured with rhGM-CSF and rhIL-4. The recombinant adenovirus vector AdEASY-EGFP was transduced into immature dendritic cells on the third day with or without adding IL-10. The expression of cell maturation marker CD83, CD86 and HLA-DR were determined with flow cytometry. Allogeneic mixed leukocyte reaction( MLR) was used to examine the imDC's ability to promote T cell proliferation.</p><p><b>RESULTS</b>The expression of surface maturation markers of imDC after transfection with adenovirus were significantly up-regulated ( CD86:46+/-10; CD83: 38 +/- 7; HLA-DR: 82 + 12) , and its ability to promote T cell proliferation was also obviously increased( SI > 2. 0). However, the expression of surface maturation markers of imDC after IL-10 treatment had lower mature phenotypes expression after transduction (CD86:8 +/- 5; CD83: 9 +/- 3; HLA-DR:63 +/- 12), and T cell stimulating ability was decreased comparing with adenovirus transfection groups.</p><p><b>CONCLUSION</b>Adenovirus can be transduced into imDC with high efficiency, but transfection itself can promote imDC's maturation. IL-10 treatment can inhibit the tendency to maturation stimulated by adenovirus transduction efficiently.</p>

Changes in plasma levels of LPS, TNFalpha and IL-6 in burn patients with severe infection treated with Imipenem or Cefoperazone / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the changes in plasma levels of lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) in burn patients with severe infection treated with Imipenem or Cefoperazone.</p><p><b>METHODS</b>Thirteen severe burn patients infected with gram negative bacilli were enrolled in the study in which 7 were treated with IPM and 6 with CPZ. Venous blood samples were harvested before and 2, 12, 24, 48 and 72 hours after the use of antibiotic for the determination of the plasma levels of LPS, TNF-alpha and IL-6, and correlative analysis was carried out among all the factors in regard to their changes.</p><p><b>RESULTS</b>The plasma levels of LPS in both groups were elevated 2 hours after the injection of either antibiotic, but it was more obvious in patients with CPZ when compared with that before treatment (13.95 +/- 5.44 pg/ml), and the levels were much higher than that after IPM (P < 0.05). The plasma LPS level declined thereafter. The plasma TNF-alpha level in CPZ group was 0.86 +/- 0.16 ng/ml at 2 hours after the use of antibiotic, and it was much higher than that before the use of the drug, and it was higher compared with IPM group. (P < 0.01). But there was no change in the plasma IL-6 level in all the patients at all the time points before and after the use of either drug. The plasma TNF-alpha levels in the two groups were positively correlated with the plasma levels of LPS and IL-6.</p><p><b>CONCLUSION</b>The release of LPS and TNF-alpha from bacteria could be induced by the administration of different kinds of antibiotics in the management of burn patients infected by gram negative bacilli in different releasing amounts. And the TNF-alpha production was correlated with the release of LPS and IL-6.</p>

Study on the anti-maturation features of immature dendritic cells induced by low dose of granulocyte macrophage colony stimulating factor / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of maturative agents, including lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF-alpha) and interferon gamma(IFN-gamma) on the maturation of immature dendritic cells originated from murine bone marrow induced by low dose of granulocyte macrophage colony stimulating factor (rm GM-CSF).</p><p><b>METHODS</b>Dendritic cells from murine bone marrow progenitors were cultured in low and high doses of GM-CSF for 6 days, and then the suspending cells were harvested for the experiment. After 3 days of co-culture of the obtained DC with low dose rmGM-CSF (GM(low)DC) with LPS, TNF-alpha and IFN-gamma, the stimulatory capacity of inducing proliferation of non-sensitized splenocytes of GM(low)DC in mixed lymphocyte reaction (MLR) was observed and compared with that of GM(high)DC.</p><p><b>RESULTS</b>GM(low)DC could not activate the non-sensitized splenocytes or induce it into proliferation after 3 days of co-incubation with LPS, TNF-alpha, IFN-gamma, with the stimulation index (SI) lower than 2. Whereas GM(high)DC could strongly activate naive splenocytes (SI = 4.71).</p><p><b>CONCLUSION</b>GM(low)DC was resistant to maturation and insensitive to the stimulation by LPS, TNF-alpha or IFN-gamma.</p>