Respiratory Muscle Contraction Characteristics and Potential Mechanisms in Severely Burned Rats.

Postburn hypermetabolism remains an important clinical problem. During this phase, there is a significant loss of diaphragmatic proteins. Better understanding of respiratory muscle dynamics and potential mechanisms affecting respiratory muscle function is necessary for the development of effective therapeutic approaches. Male Wistar rats were subjected to 50% TBSA burns and sham injuries, and respiratory muscle function was assessed with 0, 1, 4, 7, and 14 days postinjury, including pulmonary function, blood gas analysis, transdiaphragmatic pressure, diaphragm ultrasonography, isolated diaphragm contractility, fatigue index, protein oxidative stress content, and ATP levels. Burned rats had significantly reduced inspiratory time, expiratory time, and tidal volume and significantly increased respiratory rate and minute ventilation. At the same time, the isolated diaphragm contractility, specific force during fatigue, and fatigue index were significantly decreased in the burned rats. Pdi, Pdimax, diaphragm thickness, diaphragm thickening fraction, and diaphragm excursion also decreased significantly postburn, whereas the Pdi/Pdimax ratio increased significantly. Finally, the content of protein carbonyls and lactic acid of burned rats was increased, and ATP levels of burned rats were decreased. The present study demonstrates the dynamic changes in diaphragm contractile properties postburn from both in vivo and in vitro perspectives, while cursorily exploring the possibility that protein oxidative stress and reduced ATP production may be the cause of diaphragm dysfunction. This understanding contributes to the development of methods to mitigate the extent of diaphragmatic function loss after severe burns.

Research progress in mechanism and preclinical treatment for blast traumatic brain injury / 中华创伤杂志

Blast traumatic brain injury (bTBI) often causes irreversible damage to the brain which seriously endangers the lives of the wounded and can be accompanied by various complications, and has high disability and morbility in peacetime and wartime. The bTBI is divided into primary injury and secondary injury, resulting in a series of neuropsychiatric symptoms. The mechanism of bTBI contains cracking effect, implosion effect, inertia effect and cavitation effect. Multiple factors, such as shrapnel injury caused by explosion, collision of body being thrown with hard objects and smash of buildings, can lead to brain injury. There are challenges in the diagnosis and treatment of bTBI, because the injury is often closed, the onset is slow, the diagnosis is easy to missed, the pathogenesis is complex, and the clinical manifestations vary. The authors review the mechanism of bTBI and its preclinical treatment, hoping to provide a way for the preclinical treatment of bTBI.

Effects of insulin therapy on skeletal muscle wasting in severely scalded rats and its related mechanism / 中华烧伤杂志

Objective@#To explore the effects of insulin therapy on skeletal muscle wasting (SMW) in severely scalded rats and its related mechanism.@*Methods@#Totally 48 male Wistar rats aged 7-8 weeks were divided into simple scald (SS) group and insulin therapy (IT) group according to the random number table, with 24 rats in each group. After weighing the body mass and measuring the blood glycemic level of the tail end with a glucometer, the rats in the two groups were immersed in hot water at 94 ℃ for 12 seconds to make a full-thickness dorsal scald model involving 30% total body surface area. Rats in group IT were subcutaneously injected with 1 U/kg insulin glargine at 8: 00 a day from post injury day (PID) 1 to 7, whilst rats in group SS were given the same amount of normal saline. Rats in the two groups were given 10 mL/kg enteral nutritional emulsion by intragastric infusion at 8: 00 (after insulin administration), 13: 00, and 18: 00 a day respectively from PID 1 to 7. The blood glycemic levels of tail end of rats in the two groups were measured by glucometer before insulin administration on PID 1-4, 6, and 7 and on every morning of PID 8, 9, 11, 12, and 14. The body mass of rats in the two groups on PID 14 without any treatment was weighed. Eight rats from each group were collected respectively on PID 4, 7, and 14 to harvest tibialis anterior muscle (TAM) samples. The mass of TAM on PID 14 was weighed. The ultrastructural changes of TAM myocytes on PID 7 were observed with transmission electron microscope. The apoptotic rates of TAM myocytes on PID 4, 7, and 14 were assessed by the assay of terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphate-biotin nick end labeling, the expressions of cysteine-aspartic protease-3 (caspase-3) of TAM on PID 4, 7, and 14 were detected with immunohistochemistry, and protein expressions of endoplasmic reticulum (ER) stress (ERS) associated proteins glucose-regulated protein 78 (GRP78), CCAAT/enhancer binding protein-homologous protein (CHOP), and activated caspase-12 of TAM on PID 4, 7, and 14 were detected with Western blotting. Data were processed with completely random design t test, analysis of variance for repeated measurement, analysis of variance for factorial design, t test, and Bonferroni correction.@*Results@#The blood glycemic level and body mass of rats in the two groups before injury were similar (t=0.204, 0.405, P>0.05). There were no statistically significant differences in blood glycemic levels of rats between the two groups on PID 1, 6, 9, 11, 12, and 14 (t=0.229, 3.339, 1.610, 0.178, 0.181, 0.079, P>0.05). Compared with those of group SS, blood glycemic levels of rats in group IT were significantly lower on PID 2, 3, 4, 7, and 8 (t=7.245, 4.165, 4.609, 4.018, 3.995, P<0.05 or P<0.01). On PID 14, the body mass and TAM mass of rats in group IT were (271±19) g and (0.47±0.05) g respectively, both obviously higher than (254±12) g and (0.43±0.04) g of group SS (t=2.159, 2.375, P<0.05). On PID 7, nuclear pyknosis and deformation, chromosome misdistribution, and ER swelling in TAM myocytes of rats in group SS were observed; the apoptotic alterations and ER swelling of TAM myocytes were alleviated in rats of group IT as compared with those of group SS. The apoptotic rates of TAM myocytes of rats in group IT were obviously lower than those of group SS on PID 4, 7, and 14 (t=4.262, 9.153, 9.799, P<0.01). The expressions of caspase-3 in TAM of rats in group IT were obviously lower than those of group SS on PID 7 and 14 (t=10.429, 7.617, P<0.01). Compared with those of group SS, the protein expressions of GRP78 were obviously increased on PID 4 and 14 (t=4.172, 4.437, P<0.05), the protein expressions of activated caspase-12 were obviously decreased on PID 7 and 14 (t=11.049, 11.181, P<0.01), and the protein expressions of CHOP were obviously decreased on PID 4, 7, and 14 (t=13.837, 9.572, 6.930, P<0.01) in TAM of rats in group IT.@*Conclusions@#Insulin therapy may reduce skeletal muscle myocytes apoptosis and SMW by alleviating ERS in rats with severe scald.

Selection of surgical methods for postburn scar contracture deformity in children′s hands / 中华整形外科杂志

Objective@#To explore the surgical methods for children with contracture deformity on hands after burn.@*Methods@#From January 2014 to January 2018, 33 pediatric patients, a total of 42 hands with scar contracture deformities were reviewed. There were 24 males and 9 females, aged from 11 months to 6 years and 7 months. Among them, 20 hands were volar metacarpophalangeal joint contractures, 9 were volar interphalangeal joint contractures, 7 were dorsal metacarpophalangeal joint contractures (3 claw-shaped hands), 3 were hand back contractures, and 3 were palm contractures. Of the 42 hands, 36 hands were repaired with full-thickness skin grafts or split-thickness skin grafts, after the removal of contracted scar, and 6 hands were repaired with abdominal skin flaps, due to the tendon or bone exposure after the scar removal.@*Results@#Skin grafts on 31 hands were all survived after 2 weeks. However, the survival area of 3 skin grafts was about 90%, and 2 skin grafts survived about 80%. All of them healed well after dressing changing. The 6 hands repaired with abdominal skin flap healed well too. After 1-2.5 years of follow-up, finger scar contracture occurred in 4 hands with skin grafting, and they were performed scar excision and sheet skin grafting. Three hands were treated with Z-plasty, due to web space contracture. The function of other hands were normal, without contracture or deformity. The skin color and texture were similar to the surrounding skin, with limited pigmented. Scars on the edge of skin grafts was not obvious. Patients and their families were satisfied.@*Conclusions@#The sheet skin graft is the main method for postburn scar contracture in children′s hands. The abdominal skin flap should be considered, if tendon or bone is exposed, especially for large wound or multiple sites.

Analysis on treatment of eight extremely severe burn patients in August 2nd Kunshan factory aluminum dust explosion accident / 中华烧伤杂志

Objective@#To summarize the measures and experience of treatment in mass extremely severe burn patients.@*Methods@#The clinical data and treatment of 8 extremely severe burn patients in August 2 Kunshan factory aluminum dust explosion accident who were admitted in the 100th Hospital of PLA on August 2nd, 2014, were retrospectively analyzed. There were 4 males and 4 females, aging 22-45 (34±7) years, with total burn area of 55%-98% [(89±15)%] total body surface area (TBSA) and full-thickness burn area of 45%-97% [(80±21)%] TBSA. All the 8 patients were accompanied with severe shock, inhalation injury, and blast injury. According to the requirements of former PLA General Logistics Department and Nanjing Military Command, a treatment team was set up including a special medical unit and a special care unit, with Chai Jiake from the First Affiliated Hospital of PLA General Hospital as the team leader, Zheng Qingyi from the 175th Hospital of PLA (the Affiliated Dongnan Hospital of Xiamen University) as the deputy leader, the 100th Hospital of PLA as the treatment base, and burn care, respiratory, nephrology, nursing specialists from the First Affiliated Hospital of PLA General Hospital, and the burn care experts and nursing staff from the 180th Hospital of PLA, 118th Hospital of PLA, 98th Hospital of PLA, and 175th Hospital of PLA, and nurses from the 85th Hospital of PLA, 455th Hospital of PLA, 101th Hospital of PLA, 113th Hospital of PLA as team members. Treatment strategies were adopted as unified coordination by the superior, unified responsibility of team leader, division of labor and cooperation between team members, and multidisciplinary cooperation led by department of burns. With exception of one patient who received deep vein catheterization before admission, the other 7 patients were treated with deep vein catheterization 0.5 to 3.0 hours after admission to correct hypovolemic shock as soon as possible. Eight patients received tracheotomy, and 7 patients were treated with mechanical ventilation by ventilator in protective ventilation strategy with low tide volume and low volume pressure to assist breathing. Fiberoptic bronchoscopy was done one to three times for all the 8 patients to confirm airway injuries and healing status. Escharectomy and Meek dermatoplasty in the extremities of all the 8 patients were performed 3 to 6 days after injury for the first time. Escharectomy, microskin grafting, and covering of large pieces of allogeneic skin on the trunks of 4 patients were performed 11 to 16 days after injury for the second time. The broad-spectrum antibiotics were uniformly used at first time of anti-infective therapy, and then the antibiotics species were adjusted in time. The balance of internal environment was maintained and the visceral functions were protected. One special care unit was on responsibility of only one patient. Psychological intervention was performed on admission. The rehabilitative treatment was started at early stage and in company with the whole treatment.@*Results@#Acute renal injury occurred in 5 patients within 36 hours after injury and their renal function was restored to normal 4 days after injury due to active adjustment of fluid resuscitation program. No pulmonary complications, such as severe pulmonary infection and ventilator-associated pneumonia, occurred in the survived patients. One of the 8 patients died, and the other 7 patients were cured successfully. The wounds were basically healed in 2 patients in 26 or 27 days by 2 or 3 times of operation, and in 5 patients by 4 or 5 times of operation. The basic wound healing time was 26-64 (48±15) days for all the 7 patients.@*Conclusions@#Treatment strategies of unified coordination by the superior, unified responsibility of team leader, division of labor and cooperation between team members, and multidisciplinary cooperation led by department of burns are the bases to successful treatment. Correcting shock as soon as possible is the prerequisite and closing wound as soon as possible is the key to successful treatment. Comprehensive treatment measures, such as maintaining and regulating the function of viscera, improving the body immunity, and preventing and treating the complications, are the important components to successful treatment. It is emphasized that in the treatment of mass extremely severe burn patients, specialist burn treatment should always be in the dominant position, and other related disciplines may play a part in auxiliary function.

Influences of ulinastatin on acute lung injury and time phase changes of coagulation parameters in rats with burn-blast combined injuries / 中华烧伤杂志

Objective@#To explore the influences of ulinastatin on acute lung injury and time phase changes of coagulation parameters in rats with severe burn-blast combined injuries.@*Methods@#One hundred and ninety-two Sprague-Dawley rats were divided into pure burn-blast combined injury group, ulinastatin+ burn-blast combined injury group, and sham injury group according to the random number table, with 64 rats in each group. Two groups of rats with combined burn-blast injuries were inflicted with moderate blast injuries with the newly self-made explosive device. Then the rats were inflicted with 25% total body surface area full-thickness scald (hereinafter referred to as burn) on the back by immersing in 94 ℃ hot water for 12 s. Rats in sham injury group were sham injured on the back by immersing in 37 ℃ warm water for 12 s. Immediately after injury, rats in the three groups were intraperitoneally injected with Ringer′s lactate solution (40 mL/kg), meanwhile rats in ulinastatin+ burn-blast combined injury group were intraperitoneally injected with ulinastatin (4×104U/kg), once every 12 hours, until post injury hour (PIH) 72. Before injury, at PIH 3, 6, 12, 24, 48, 72, and on post injury day (PID) 7, 8 rats in each group were selected to harvest abdominal aortic blood samples to detect plasma levels of activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen, D-dimer, antithrombin Ⅲ (AT-Ⅲ), and α2-antiplasmin (α2-AP). At PIH 24, three rats in each group which were used in detection of coagulation parameters were sacrificed to observe lung injury. At PIH 72, three rats in each group were sacrificed for histopathological observation of lung. Data were processed with analysis of variance of factorial design and least-significant difference test.@*Results@#(1) Compared with those of rats in sham injury group, APTT of rats in pure burn-blast combined injury group significantly prolonged at PIH 72 and on PID 7 (P<0.05 or P<0.01). PT significantly prolonged at PIH 3 and 72 and significantly shortened at PIH 6 (P<0.05 or P<0.01) . Fibrinogen level significantly increased from PIH 12 to PID 7 (P<0.01). AT-Ⅲ level significantly decreased at PIH 6 and 12 (P<0.01), and α2-AP level significantly decreased at PIH 6 and significantly increased from PIH 24 to 72 (P<0.01). Compared with those of rats in pure burn-blast combined injury group, APTT of rats in ulinastatin+ burn-blast combined injury group significantly prolonged at PIH 3 and 6 (P<0.01) while PT significantly shortened at PIH 3, 12, and 72 (P<0.05 or P<0.01). Fibrinogen level significantly decreased at PIH 6 and 12 and significantly increased at PIH 72 (P<0.05 or P<0.01). AT-Ⅲ level significantly increased at PIH 3, 12, 48, and 72 (P<0.05 or P<0.01), and α2-AP level significantly decreased from PIH 12 to 72 (P<0.05 or P<0.01). D-dimer level of rats in sham injury group, pure burn-blast combined injury group, and ulinastatin+ burn-blast combined injury group were respectively (0.084±0.013), (0.115±0.015), (0.158±0.022), (0.099±0.011), (0.099±0.012), (0.089±0.011), (0.124±0.014), and (0.116±0.018) μg/mL, (0.064±0.033), (0.114±0.016), (0.135±0.009), (0.060±0.008), (0.104±0.010), (0.124±0.020), (0.180±0.036), and (0.201±0.032) μg/mL, (0.074±0.013), (0.084±0.035), (0.101±0.050), (0.091±0.046), (0.096±0.034), (0.044±0.019), (0.106±0.049), and (0.118±0.047) μg/mL. Compared with that of rats in sham injury group, D-dimer level significantly decreased at PIH 6 and 12 and significantly increased from PIH 48 to PID 7 (P<0.05 or P<0.01). Compared with that of rats in pure burn-blast combined injury group, D-dimer level of rats in ulinastatin+ burn-blast combined injury group significantly decreased at PIH 3, 48, and 72, and on PID 7 (P<0.05 or P<0.01). (2) At PIH 24, there was a large amount of light red effusion in the thoracic cavity, and both lung lobes were hyperemic and edematous with a small amount of blood clots in the left and middle lobe of rats in pure burn-blast combined injury group. There was a small amount of yellowish effusion in the thoracic cavity of rats in ulinastatin+ burn-blast combined injury group, and the degree of hyperemic and edematous of bilateral lobes was lighter compared with rats in pure burn-blast combined injury group with no clot in the left lobe. No congestion, edema, or bleeding was observed in lungs of rats in sham injury group. (3) At PIH 72, disorganized alveolar structure, collapsed alveolar cavity, edematous and thickening pulmonary interstitium, infiltration of a large amount of inflammatory cells, obvious rupture of alveolar septum, and hyaline thrombus were observed in lungs of rats in pure burn-blast combined injury group. Significantly improved alveolar structure, less collapsed alveolar cavity, improved edematous pulmonary interstitium, less infiltration of inflammatory cells, rupture of alveolar septum, and no thrombus were observed in lungs of rats in ulinastatin+ burn-blast combined injury group. The lung tissue had a well-filled alveolar cavity with no interstitial edema or infiltration of inflammatory cells and no thrombosis in lungs of rats in sham injury group.@*Conclusions@#Ulinastatin has positive therapeutic effects on acute lung injury in rats with severe burn-blast combined injuries through its good regulating effects on coagulation and fibrinolytic disorders caused by burn-blast combined injuries.

Expression signatures of lncRNAs in skeletal muscles at the early flow phase revealed by microarray in burned rats.

BACKGROUND: Severe thermal trauma covering more than 30% of the total body surface area (TBSA) triggers a sustained pathophysiological response, which includes, but is not limited to, hypermetabolism, chronic inflammation, and severe skeletal muscle wasting. Long non-coding RNAs (lncRNAs) are an important class of pervasive genes involved in a variety of biological functions. However, the functions of lncRNAs in the regulation of responses of skeletal muscle wasting after severe burn have remained untested. METHODS: Presently examined were the expression profiles of lncRNAs and messenger RNAs (mRNAs) in skeletal muscle tissues of 3 pairs of burned rats at the early flow phase, compared with sham rats, using microarray. Each potential lncRNA-mRNA pair identified is a strong candidate in the definitive confirmation of the presence of specific lncRNA-mRNA interactions, thus providing a detailed picture of the pathogenesis of skeletal muscle wasting in burned rats. RESULTS: LncRNA expression levels were compared among 3 injured tissues and matched normal tissues from microarray data. An average of 117 significantly differentially expressed lncRNAs (1.5-fold) were identified. Only 202 mRNAs were significantly upregulated or downregulated, an average of 92 mRNAs were upregulated in injured, compared to matched normal, tissues, while an average of 110 mRNAs) were downregulated. CONCLUSION: Presently identified were lncRNAs differentially expressed in skeletal muscles of burned rats, compared to normal tissues. Regulatory pathways may be involved in the pathogenesis of skeletal muscle wasting. Each lncRNA-mRNA pair identified is a strong candidate for a future study to definitively confirm the presence of specific lncRNA-mRNA interactions, thus providing a more detailed picture of the pathogenesis of skeletal muscle wasting in burned rats.

[Current situation of research and application of Parkland formula in burn resuscitation].

Parkland formula is the most widely used resuscitation formula in burn care. However, a growing number of disputes have been raised along with the development of medical technology, among which its total volume and composition of the fluid are the two foci. Firstly, Parkland formula may lead to an untoward phenomenon nicknamed "fluid creep", which may lead to complications such as abdominal compartment syndrome. Secondly, along with the deeper understanding of how permeability of blood vessels changes after burn injury, colloid is recommended to be given after the third 8 h post-burn. Additionally, controversy exists in the choice of different colloid solutions. The safety of different colloid solutions remains to be further elucidated. This article will deal with all of the above-mentioned problems.

Detection of the MicroRNA expression profile in skeletal muscles of burn trauma at the early stage in rats.

BACKGROUND: Severe burn injuries are associated with a persistent hypermetabolic response, which causes long-term loss of muscle mass that results in a clinical negative balance of nitrogen and muscle wasting. MicroRNAs (miRNAs) play a critical role in post-transcriptional regulation of gene expression, which negatively regulates gene expression by promoting degradation of target mRNAs or inhibiting their translation. However, the mechanisms of skeletal muscle wasting after severe burn involved in miRNAs still remain unclear. METHODS: In this study, the alterations of miRNAs expression profile in skeletal muscles of thermal rats were detected at an early stage by microarray. All data were presented as mean±SD. Statistical analysis was determined by independent Student's t-test and one-way ANOVA. The significance was all set at p<0.05, and fold change cut-off was 2.0 for microarray. Significant differentially expressed miRNAs were identified through Volcano Plot filtering. Hierarchical clustering was performed using MEV software (v4.6, TIGR). RESULTS: Thousands of miRNAs could be examined in normal and injured tissues, but only 69 of these were significantly upregulated or down-regulated, which could be used to discriminate skeletal muscles of thermal rats from matched tissues. CONCLUSION: The deregulated miRNAs probably play a potential role in the pathogenesis of skeletal muscle wasting in burn trauma.

Lay emphasis on the application of negative pressure wound therapy technique in burn surgery / 中华烧伤杂志

In recent years, negative pressure wound therapy (NPWT) technique has been widely used in burn surgery, including wound repair, skin grafting, and cosmetic procedures, showing promising clinical results. Based on the literature and clinical experience, the mechanism of NPWT and its clinical application in burn surgery are briefly iterated herewith.

A Randomized,Multi-center and Parallel Control Clinical Trial for Acidic Fibroblast Growth Factor in the Treatment of Deep Second Degree Burn / 中国药师

Objective:To evaluate the efficacy and safety of recombinant human acidic fibroblast growth factor( rh-aFGF)and re-combinant human basic fibroblast growth factor( rh-bFGF)in the treatment of deep second degree burn. Methods:A multicenter,pro-spective,randomized and double-blind clinical trial was conducted. Totally 216 cases of deep second degree burn were selected from five research centers and given appropriate antibiotics and nutritional supplement therapy. The wound of 108 cases in the observation group were rinsing with rh-aFGF(one bottle / 5cm2)according to the wound area at the time of admission followed by rh-aFGF daily spraying,3-4 press/cm2 ,6-8 times a day. The 108 patients in the control group were treated with rh-bFGF with the same regimen as the observation group. After the 30-day follow-up,the wound healing was evaluated in the two groups. Results:The complete healing time,debridement time,complete healing rate in 12 days and 15 days in the observation group were all better than those in the control group(P<0. 05). After the 7-day treatment,the level of leukocyte and seepage score of the observation group were both lower than those of the control group(P<0. 01). The moderate rate showed significant difference between the two groups(P<0. 05). Conclu-sion:rh-aFGF shows better clinical efficacy than rh-bFGF in the treatment of deep second degree burn with the similar safety.

Advances in the research of the role of mesenchymal stem cell in wound healing / 中华烧伤杂志

Wound healing is a dynamic and complicated process, which generally takes three overlapping phases: inflammation, proliferation, and remodeling. If wounds complicated by severe trauma, diabetes, vascular dysfunction disease, or a massive burn injury failed to pass through the three normal phases of healing, they might end up as chronic and refractory wounds. Mesenchymal stem cells (MSCs) play different important roles in the regulation of all the phases of wound healing. MSCs can be recruited into wound and differentiated into wound repair cells, as well as promote wound healing by exerting functions like anti-inflammation, anti-apoptosis, and neovascularization. This review focuses on the role and mechanism of MSCs in each phase of the wound healing process.

Effects of endotoxin/lipopolysaccharide on proliferation and apoptosis of human umbilical cord mesenchymal stem cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effects of different concentrations of lipopolysaccharide (LPS) on proliferation and apoptosis of human umbilical cord mesenchymal stem cells (hUCMSCs) in vitro, and to explore their possible mechanism.</p><p><b>METHODS</b>hUCMSCs from umbilical cord tissue of full-term healthy fetus delivered by caesarean section were isolated and cultured in vitro using tissue attachment method. The 3rd passage hUCMSCs were used in the study. Cells were divided into groups A, B, C, D, and E, which were treated with DMEM/F12 medium containing 0, 0.1, 1.0, 10.0, and 100.0 µg/mL of LPS respectively. In groups B, C, D, and E, methyl-thiazole-tetrazolium assay was used to detect proliferative activity of hUCMSCs at post treatment hour (PTH) 12, 24, and 48 (denoted as absorption value), with 5 samples in each group at each time point; apoptosis of hUCMSCs at PBH 24 was identified with acridine orange-ethidium bromide (AO-EB) staining, with 4 samples in each group; apoptotic rate of hUCMSCs was determined by flow cytometer, with 5 samples in each group. Above-mentioned indexes were determined in group A at the same time points. Data were processed with analysis of variance and LSD- t test.</p><p><b>RESULTS</b>(1) There was no statistically significant difference in proliferative activity of hUCMSCs at PTH 12 among groups A, B, C, D, and E (with t values from -1.67 to 1.33, P values above 0.05). Compared with that of group A, proliferative activity of hUCMSCs was increased in groups B, C, and D at PTH 24 and 48 (with t values from -13.42 to 17.34, P < 0.05 or P < 0.01), especially so in group C. Proliferative activity of hUCMSCs was lower in group E at PTH 24 and 48 than in group A (with t values respectively 8.64 and 17.34, P values below 0.01). (2) Obvious apoptosis of hUCMSCs was observed in group E but not in the other 4 groups with AO-EB staining. (3) Apoptosis rates of hUCMSCs in groups A, B, C, D, and E were respectively (3.1 ± 0.6)%, (2.6 ± 0.7)%, (2.9 ± 0.8)%, (3.1 ± 0.4)%, (25.1 ± 2.7)% (F = 272.19, P < 0.01). Apoptotic rate of hUCMSCs in group B, C, or D was respectively close to that in group A (with t values respectively 1.22, 0.57, -0.14, P values above 0.05), but it was higher in group E than in group A (t = -17.63, P < 0.01).</p><p><b>CONCLUSIONS</b>hUCMSCs proliferation may be promoted by low concentration of LPS. hUCMSCs proliferation is inhibited or induced to apoptosis along with the increase in concentration of LPS, and it may be related to activation of different major molecular signaling pathways by different concentrations of LPS.</p>

Advances in the research on the relationship between brown adipose tissue and metabolism in burn and trauma / 中华烧伤杂志

Hypermetabolism and insulin resistance are prominent features of trauma including burn injury, surgery, and infection. Hypermetabolism results in insufficiency in energy supply, which induces organ function lesion, immune suppression, high infection rate, and wound healing delay, thus exerting a strong impact on patients' quality of life and prognosis. The molecular mechanism in the occurrence and development of hypermetabolism is very complicated, and it has not been fully elucidated. Recently, brown adipose tissue (BAT) was found to be present not only in rodents but also in humans, and its activity was associated with resting metabolic rate. BAT may become the new target of research in prevention and control of metabolic disorder.

Effect of Poloxamer 188 on deepening of deep second-degree burn wounds in the early stage.

OBJECTIVE: To discuss the effect of Poloxamer 188 (P188) on deepening of deep second-degree burn wounds in the early stage after burn. METHODS: We divided Wistar rats with deep second-degree burn wounds on the backs thereof into two groups, then intravenously injected P188 for the treatment group and intravenously injecting physiological saline for the control group, detecting the activity of Na(+)-K(+)-adenosine triphosphatase (Na(+)-K(+)-ATPase), myeloperoxidase (MPO) and the content of malonaldehyde (MDA) and succinic dehydrogenase (SDH) in the burn wound, and showing the degree of necrosis in the wound by haematoxylin-eosin (HE) and proliferating cell nuclear antigen (PCNA) immunohistochemical staining. RESULTS: In the control group and treatment group, the activity of SDH and Na(+)-K(+)-ATPase dropped to the lowest point 24 h after the burn took place, and then increased gradually, but was still far lower than the normal level at the furthest time point. At 24 h after burn, activity of SDH and Na(+)-K(+)-ATPase in the treatment group was higher than that of the control group (P<0.05); the activity of MPO of the control group reached the highest point at 24 h while that of MPO of the treatment group reached the highest point after 48 h; later, that of MPO of both groups decreased, but was still higher than the normal level. Compared with the highest values of the activity of MPO of both groups, that of the control group was higher than that of the treatment group (p<0.05); the contents of MDA of both groups kept increasing after the burn; 72 h later, that of the control group was higher than that of the treatment group (p<0.05). HE and PCNA staining showed progressive damage of the wound in the treatment group, which was decreased with treatment, particularly at the early stages. CONCLUSION: Systemic application of P188 on deep second-degree burn wounds at the early stage may alleviate wound deepening, whose mechanism may be related to timely sealing up the damaged cell membrane and inhibiting the inflammatory reaction.

Clinical application and long-term follow-up study of porcine acellular dermal matrix combined with autoskin grafting.

The purpose of this study was to investigate the clinical effects of porcine acellular dermal matrix combined with autoskin grafting on full-thickness skin defects using long-term clinical follow-up study and histologic examination. One hundred fifty-two patients with deep burn or trauma hospitalized from February 2000 to July 2003 were repaired with porcine acellular dermal matrix and split-thickness autoskin graft. Take rate of the grafts was calculated on 1 week after operation. Scar hyperplasia was examined on 1, 3, 6, and 12 months after operation. At the same time, the contracture rates of grafted areas were also calculated. Skin biopsy was performed on five patients for histologic examination, as well as transmission electron microscopy 78 months after operation. The take rate of grafts of 116 patients (76.3%) was 100%, and the take rate of the rest of the patients (36 patients, 23.7%) was more than 95%. No one needed skin transplantation for the second time. One hundred twenty-seven patients were followed up on 1 month after operation; grafts showed mild contraction. There was slight cicatricle at skin junction with tender texture. There was no obvious pruritus and blister. One hundred one patients were followed up on 3 months after operation. The graft contraction showed obvious relief with good articular function. Eighty-two patients were followed up on 6 months after operation. The color and texture of the grafts were similar to normal skin without obvious cicatricial hyperplasia. Fifty-eight patients were followed up on 12 months after operation. The grafts were similar to normal skin without obvious rejection. There were no significant differences between the contracture rates at 3, 6, and 12 months and 1 month after the second surgery. Sixteen patients were followed up on 78 months after operation. The appearance of grafts was slightly dry compared with normal skin. Tissue structure of grafts was similar to normal skin with sweat gland-like structure, and sweat gland cells were shown in the dermis. Xenogenic acellular dermal matrix combined with split-thickness autograft can repair full-thickness skin defects and inhibit scar proliferation without obvious immune rejection for long time. Newly formed sweat gland-like structure and sweat gland cells in the dermis may be a new research point for reconstruction of skin function.

Island scapular flap based on transverse branch of circumflex scapular artery for axillary burn scar contracture / 中华医学美学美容杂志

Objective Island scapular flap (ISF) based on transverse branch of circumflex scapular artery is less reported than ISF based on ascending or descending branch. This article presented authors' experiences in correction of severe axillary burn scar contracture with ISF based transverse branch of circumflex scapular artery. Methods ISFs based transverse branch was harvested in 12 patients with 15 severe axillary burn scar contracture, rotating an arc of about 180°. Flap size was between 12 cm× 5cm to 20 cm × 10 cm. The donor site was closed primarily. Results All 15 flaps survived completely and axillary burn scar contracture was corrected successfully. 8 patients were satisfied with both the functional and aesthetic results after 1-3 years' follow-up. Conclusion ISF based transverse branch of circumflex scapular artery is a good choice for reconstruction of severe axillary burn scar contracture, especially for female patients or ones whose ISF based on ascending or descending branch could not be harvested because of formation of hypertrophic scar in donor site.

Large cranial bone defect reconstructed by titanium implant of CAD/CAM / 中华医学美学美容杂志

Objective To explore a method of large cranial bone defect reconstructed by titanium implant with computer aided design(CAD)/computer aided manufacture(CAM)technique.Methods From April 2006 to June 2008,7 cases of cranial bone defect due to tumor and trauma were admitted.The data of skull bone defects were obtained by CT.The resin model was designed and manufactured with rapid prototyping technique.Results The CT data could be used by image software directly.The resin model was manufactured accurately by RP technique.The titanium implant design could be completed by CAD/CAM.7 patients achieved one stage healing.After a follow-up of 6 months to 1 year,cranial bone defect was reconstructed satisfactorily.Conclusion Individual design and repair of large cranial bone defect with CAD/CAM technique is worth extending application clinically.It is a quite ideal and very simple method for the surgical treatment of the cranial bone defect.

Changes in Bacteria Species in Severe Burn Wounds at Different Stages / 中华医院感染学杂志

OBJECTIVE To analyze the changes in bacteria constitution in severe burn wounds in different stages so as to provide reference for clinical prevention and treatment.METHODS A total of 36 casualties with severe burn injuries(≥50.0% total burn surface area) and hospitalized within 5 days post-burns from 2004 to 2006 were enrolled in the study.Samples were collected in the burn wounds from the first day to two months post-burns.RESULTS Totally 476 bacterial strains were isolated and Gram-negative bacteria accounted for 64.1%.However,in term of the single bacterial strain,Staphylococcus aureus(SAU) ranked first and the follows were Pseudomonas aeruginosa(PAE) and Acinetobacter baumannii(ABA).During the first week and the six weeks to 2 months post-burns,Gram-positive bacteria were dominant and SAU ranked first.From the second week to the fifth week,Gram-negative bacteria were dominant,PAE and ABA were the main bacteria.Even though Gram-negative bacteria dominated in these periods,SAU still ranked the first or the second in terms of single bacterial strain.CONCLUSIONS Bacteria constitution in burn wounds differs in different stages.It must be stressed to prevent infections of SAU regardless of any stages,as well as ABA infections since the percentage of ABA has increased markedly in recent years.

Effect of carbachol on the expression of la on monocyte and lymphocyte apoptosis rate of the burned rats with delayed resuscitation / 中国医师杂志

Objective To explore the changing trend of Ia on monocyte, lymphocyte apoptosis rate, TNF-α and IL-6 in abdominal aorta of burned rats with delayed resuscitation and the influence of application of carbachol on them. Methods Adult male Wistar rats were randomly divided into normal control group(n =8), scald group(n =48) and scald with carbachol treatment group(n =48). In latter two groups, rats were inflicted with 30% total body surface area (TBSA) full-thickness scald and delayed fluid resuscitation. All scald rats were sacrificed at the 6th hours or 1st, 2nd, 3rd, 7th, 14th day after scald, with 8 rats at each time point. Expression of Ia antigen on monocyte and lymphocyte apoptosis rate were determined by direct immunofluorescence on a flow cytometer, and TNF-α and IL-6 was measured by ELISA. Results Expression of la on monocyte was obviously lower than that of controls. The lowest levels were recorded on the 6th hours and 1st day after scald. Subsequently, Ia was elevated gradually, but still lower than that of normal rats(P <0. 01). After administration of carbachol, Ia expression was obviously promoted, compared with the simple scald group (P <0. 01). Lymphocyte apoptosis rate, TNF-α and IL-6 was higher than that of controls(P <0. 01). After administration of cavachol, , lymphocyte apoptosis rate and TNF-α and IL-6 was obviously down-regulated on the 6th hours, 1st day, 2nd day and 3rd day after scald injury, compared with the simple scald group (P < 0. 01 or 0. 05). Conclusion After severe burn with delayed fluid resuscitation, there is a low la expression, high lymphocyte apoptosis rate and increased releasing of proinflammatory cytokine. Immune function was suppressed. Carbacho] could improve the immune function of scald rats with delayed fluid resuscitation.