The epidemiology of alcohol burns at a major burn centre in North China.

This study was designed to explore the epidemiological characteristics and potential preventive strategies of alcohol burns. In this five-year, retrospective study, 163 patients with alcohol burns (admitted from 1 January 2015 to 31 May 2020 were included. There was a male-to-female ratio of 1.1:1, a mean age of 34.1±16.8 years, and a mean burn size of 13.3±13.7% total body surface area (TBSA). The number of patients with alcohol burns was similar year by year during the five-year period. Just over half of patients (n=84, 51.5%) sustained a third-degree burn injury, which was significantly associated with a longer hospital stay and the need for surgery. The most prevalent aetiology was cupping (n=49, 29.5%), followed by cooking hotpot (n=37, 22.7%). Of the patients, seven (4.29%) sustained injuries during experiments at school and one patient sustained injury when using alcohol spray for disinfection against COVID-19. The incidence of facial burn injury (n=105, 64.4%) was significantly higher than previously reported data (33.2%). The result of the study showed that cupping and hotpot were the main causes of alcohol burns in Beijing, which should be taken into consideration for prevention. It is necessary to strengthen safety management of classes at school where experiments are undertaken and to educate the general public on the proper means of disinfecting against COVID-19.

An innovated elastic compression hemostasis technique for extremity excision in patients with extensive burns: A prospective clinical randomized controlled trial.

OBJECTIVE: To introduce an innovative elastic compression hemostasis technique for extremity excision in extensively burnt patients and investigate its effectiveness. METHODS: Ten patients were included and divided into 2 groups: the control group (4 patients, 12 extremities) receiving the conventional hemostasis technique and the experimental group (6 patients, 14 extremities) receiving the innovative technique. General data of the patients were collected, excision size measured, hemostasis time recorded, average blood loss per 1% total body surface area of the excised wound calculated, incidence of subcutaneous hematoma and take rate determined. RESULTS: The 2 groups had no statistical difference in the baseline data. Average blood loss per 1% total body surface area of the excised wound in the upper and the lower extremities was (62.1 ± 11.5) mL and (35.6 ± 11.0) mL in the experimental group, significantly less than (94.3 ± 6.9) mL and (82.3 ± 6.2) mL in the control group; a reduction of 34.1% and 56.8% respectively. Hemostasis time in the upper and the lower extremities were (5.0 ± 0.7) min/1% total body surface area and (2.6 ± 0.3) min/1% total body surface area, respectively, in the experimental group, significantly less than (7.4 ± 0.6) min/1% total body surface area and (4.0 ± 0.9) min/1% total body surface area in the control group; a reduction of 31.8% and 34.9% respectively. The incidences of subcutaneous hematoma were 7.1% and 8.3%, and the take rate (85.9 ± 6.0)% and (86.5 ± 4.8)% in the experimental and the control group, respectively, with no statistically significant differences. CONCLUSION: The innovative elastic compression hemostasis technique is a reliable new method that significantly reduces blood loss during extremity excision in patients with extensive burns and is worth wider understanding and application.

A novel skin grafting modality: prefabricated large sheet of postage-stamp autografts and allografts to repair extensive burn wounds; a prospective matched-control study.

BACKGROUND: The excessively long operative time has been the greatest barrier to the success of transplanting postage-stamp auto- and allografts directly and piece-by-piece onto extensive burn wounds. To solve this challenge, the authors present a novel grafting modality, that is, the prefabricated-large-sheet grafting that moves the labor-intensive and time-consuming process of grafts-positioning before grafting and thereby markedly shortens the operative time. METHODS: Twenty-one operations using the novel modality were performed on 11 patients with extensive deep burns. The grafting time using the novel modality was recorded and compared with that of the conventional piece-by-piece grafting. Eventually, the take rates of the two modalities were compared. RESULTS: All patients were healed and discharged. The average grafting time per unit area (100 cm2) of prefabricated-large-sheet grafting and piece-by-piece grafting were (0.41±0.09) min and (7.46±1.07) min, respectively, and the difference is statistically significant(P<0.001). The average take rate of the prefabricated sheets was (85.43±6.14)% and that of the piece-by-piece transplanted grafts was (87.29±5.23)% and there is no significant difference(P>0.05). CONCLUSIONS: The prefabricated-large-sheet grafting significantly reduces the intraoperative grafting time while ensures uniformity of the skin grafts and secures good outcomes, thereby making the intermingled transplantation of postage-stamp auto- and allografts, which has been an excellent modality per se but limited to repair small residual wounds, now feasible to repair extensive deep burn wounds. It is worth wider understanding and application in the treatment of extensive deep burns.

Platelet distribution width associated with short-term prognosis and cost in paediatrics with partial-thickness thermal burns: A retrospective comparative study.

Platelets exert important roles in burn wound healing and involving in inflammatory regulation and tissue repair. Platelet distribution width (PDW) is an indicator representing platelet morphology and activation. In this study, we try to evaluate the value of PDW in predicting short-term prognosis and cost of paediatrics with partial-thickness thermal burns. This retrospective study enrolled 73 children with partial-thickness thermal burns. The Ability of PDW to predict wound healing was evaluated by receiver operating characteristic (ROC) curve. All 73 patients were assigned into high and low PDW group according to optimal cut-off value from ROC curve. Associations between PDW and 2-weeks healing rate, time to wound healing, in-hospital cost and length of stay were evaluated. Furthermore, Univariate and multivariate logistic regression analysis were used to furtherly evaluate the significance of PDW in wound healing. We found that all baseline characteristics between groups were comparable (all P > .05). High PDW group had a significant higher 2-weeks wound healing rate than those with a low PDW (66.7% versus 32.6%, P < .01). Moreover, the mean time to wound healing of high PDW was obviously shorter than that of low PDW group (15.4 ± 10.1 vs 20.7 ± 10.9, P = .04). Univariate (OR: 0.24, 95%CI: 0.09-0.65, P < .01) and multivariate (OR: 0.15, 95CI%:0.05-0.52, P < .01) analysis confirmed PDW as an independent marker for wound healing. Patients in high PDW group had a significant lower medical burden than low PDW group, including in-hospital cost (13.7 ± 10.6 vs 21.9 ± 16.7, ×103RMB, P = .02) and length of stay (12.2 ± 8.8 vs 19.0 ± 10.8 days, P < .01). In conclusion, PDW can sever as a potential indictor to predict the short-term prognosis of paediatrics with partial thickness thermal burns.

Use of Fresh Scalp Allografts From Living Relatives for Extensive Deep Burns in Children: A Clinical Study Over 7 Years.

Conventionally, pediatric patients with major burns need frozen cadaveric allografts to save their lives. However, these allografts are insufficient in many burn units because of cultural and local governmental laws in China. This paper reported 22 pediatric patients with major burns who received fresh scalp allografts from their parents, siblings, or relatives from January 2011 to December 2017. These 22 pediatric patients sustained deep partial-thickness to full-thickness burns involving 40% total body surface area (TBSA) on average. Wounds were covered with fresh scalp allografts alone or with postage stamp autografts and fresh scalp allografts post excision. Data were collected from medical files of the treated patients, including sex, age, etiology of burn injury, abbreviated burn severity index (ABSI), and TBSA. Postoperative variables included early survival rate of skin grafts, mean time to rejection, length of hospital stay (LHS), healing time of donor sites, and follow-up complications of donors. The 1-year survival rate of the 22 pediatric patients included into the study was 100%. The early survival rate of the scalp allografts was similar to the autografts. The mean time to rejection was 15.5 ± 3.60 days. The average LHS was 58 days. All donor sites healed within 7.6 days on average, without scar formation, alopecia areata, or folliculitis. Following up data of the donors revealed a full psychological sense of accomplishment and no regrets of donating the scalp to save the burned children. Therefore, the use of fresh scalp allografts is a feasible alternative to save pediatric patients with major burns when frozen allografts are unavailable.

Acute downregulation of miR-155 leads to a reduced collagen synthesis through attenuating macrophages inflammatory factor secretion by targeting SHIP1.

Fibrosis, tightly associated with fibroblasts collagen synthesis, is related closely with inflammatory response. Our previously study found that acute downregulation of miR-155 at wound sites leads to a reduced fibrosis, however its particular mechanism is unclear. Herein, we aimed to explore the mechanism of miR-155 in reducing fibrosis. We first found that down-regulation of miR-155 inhibited macrophages transforming growth factor-ß1 (TGF-ß1) and IL-1ß secretion. Next, we found that co-cultured with macrophages increased the proliferation and collagen synthesis of fibroblasts, and downregulation of miR-155 in macrophages could effectively attenuate the accelerative effects. We further identified SH2 domain containing inositol-5-phosphatase 1 (SHIP1) as a direct target of miR-155 in macrophages, and the expression of SHIP1 was negatively correlated with the level of miR-155. We further confirmed that PI3K/Akt pathway was involved in this process. Last, we found that downregulation of miR-155 leads to a reduced fibrosis in sever burn rat. Taken together, these results indicate that down-regulation of miR-155 leads to a reduced fibroblasts proliferation and collagen synthesis through attenuating macrophages TGF-ß1 and IL-1ß secretion by targeting SHIP1 via PI3K/Akt pathway, suggesting its potential therapeutic effects on the treatment of skin fibrosis.

Insulin down-regulates the expression of ubiquitin E3 ligases partially by inhibiting the activity and expression of AMP-activated protein kinase in L6 myotubes.

While insulin is an anabolic hormone, AMP-activated protein kinase (AMPK) is not only a key energy regulator, but it can also control substrate metabolism directly by inducing skeletal muscle protein degradation. The hypothesis of the present study was that insulin inhibits AMPK and thus down-regulates the expression of the ubiquitin E3 ligases, muscle atrophy F-box (MAFbx) and muscle RING finger 1 (MuRF1) in skeletal muscle cells. Differentiated L6 myotubes were treated with 5-aminoimidazole-4-carboxamide-1-ß-4-ribofuranoside (AICAR) and/or compound C to stimulate and/or block AMPK respectively. These treatments were also conducted in the presence or absence of insulin and the cells were analysed by western blot and quantitative real-time PCR. In addition, nucleotide levels were determined using HPLC. The activation of AMPK with AICAR enhanced the mRNA levels of MAFbx and MuRF1. Insulin reduced the phosphorylation and activity AMPK, which was accompanied by reduced MAFbx and MuRF1 mRNA levels. Using a protein kinase B (PKB/Akt) inhibitor, we found that insulin regulates AMPK through the activation of Akt. Furthermore, insulin down-regulated AMPK α2 mRNA. We conclude that insulin inhibits AMPK through Akt phosphorylation in L6 myotubes, which may serve as a possible signalling pathway for the down-regulation of protein degradation. In addition, decreased expression of AMPK α2 may partially participate in inhibiting the activity of AMPK.

Extracellular signal-regulated kinase-mammalian target of rapamycin signaling and forkhead-box transcription factor 3a phosphorylation are involved in testosterone's effect on severe burn injury in a rat model.

BACKGROUND: Testosterone and androgen receptor agonists have been known for a long time to prevent or reverse muscle wasting in burn injury patients, but the exact molecular mechanisms are not clear. OBJECTIVE: To investigate the underlying molecular mechanisms of testosterone in severely burned rats. METHODS: Severe burn injuries were induced by immersing the back of the rat in 100 °C water for 12 s. Rats were treated for 14 days with vehicle (burn group) or a physiological replacement dose of testosterone (B + T group) immediately after injury. Gene and protein expressions were assessed by real-time polymerase chain reaction and Western blot. RESULTS: Testosterone improved glucose metabolism, reduced body weight loss, and attenuated tibialis anterior muscle mass loss and muscle protein breakdown. In rat tibialis anterior muscle, testosterone positively regulated the insulin-sensitive glucose transporters Glut3 and Glut4 genes and glycogen synthase 1 protein. These changes would be expected to improve glucose metabolism and nutrient availability in skeletal muscle. Administration of testosterone negatively regulated atrogin 1 (Fbxo32) by increasing total and phosphorylated Foxo3a (forkhead-box transcription factor 3a) levels and positively regulated the expression of the mammalian target of rapamycin (mTOR) and its downstream proteins p70S6 and S6 through mTOR-extracellular signal-regulated kinase phosphorylation. CONCLUSIONS: RESULTS suggested that testosterone might regulate skeletal muscle glucose and protein metabolism following burn injury in part by affecting extracellular signal-regulated kinase-mTOR signaling and Foxo3a levels.

A novel model of burn-blast combined injury and its phasic changes of blood coagulation in rats.

Burn-blast combined injury has a complex pathological process that may cause adverse complications and difficulties in treatment. This study aims to establish a standard animal model of severe burn-blast combined injury in rats and also to investigate early phasic changes of blood coagulation. By using 54 Wistar rats, distance from explosion source (Hexogen) and size of burned body surface area were determined to induce severe burn-blast combined injury. Thereafter, 256 rats were randomly divided into four groups (n = 64): blast injury group, burn injury group, burn-blast combined injury group, and sham injury group. Gross anatomy and pathological changes in lungs were investigated at 3, 24, 72, and 168 h, respectively. Blood was also collected for analyzing coagulation parameters as prothrombin time, activated partial thromboplastin time, and plasma levels of fibrinogen, D-dimer, antithrombin III, and α2-antiplasmin from 0 to 168 h after injury. Severe burn-blast combined injury was induced by inflicting rats with a moderate blast injury when placing rats 75 cm away from explosion source and a full-thickness burn injury of 25% total body surface area. The rats with burn-blast combined injury had more severe lung injuries when compared with the other three groups. Pathological examination in the BBL group showed diffused alveolar hemorrhage, fluid filling, alveolar atelectasis, rupture and hyperplasia of partial alveolar septum, emphysema-like change, reduced capillary bed, and infiltration of extensive polymorphonuclear cells after injury. The blood of combined injured rats was in a hypercoagulable state within 24 h, shortly restored from 24 to 48 h, and rehypercoagulated from 48 to 72 h after injury. A secondary excessively fibrinolytic function was also found thereafter. The rat model of burn-blast combined injury was successfully established by simulating real explosion characteristics. Rats with burn-blast combined injuries suffered from more severe lung injuries and abnormal coagulation and fibrinolytic function than those induced by a burn injury or a blast injury component. Hence, a time-dependent treatment strategy on coagulation function should be emphasized in clinical therapy of burn-blast combined injury.

Role of neutrophil elastase in lung injury induced by burn-blast combined injury in rats.

OBJECTIVE: Neutrophil elastase (NE) takes part in the pathogenesis of acute lung injury. However, its role in lung injury of burn-blast combined injury is unclear. Our objective was to assess the role of NE, and effect of sivelestat, a specific NE inhibitor, in lung injury induced by burn-blast combined injury in rats. METHODS: One hundred and sixty male Sprague-Dawley rats were randomly subjected to burn-blast combined injury (BB) group, burn-blast combined injury plus sivelestat treatment (S) group or control (C) group. Blood gas, protein concentration and NE activity in bronchoalveolar lavage fluid (BALF), pulmonary myeloperoxidase (MPO) activity, serum concentrations of TNF-α and IL-8, etc. were investigated from 0 h to 7 d post-injury. RESULTS: In BB group, PaO2 decreased, while NE activity in BALF, total protein concentration in BALF, pulmonary MPO activity and W/D ratio, serum concentrations of TNF-α and IL-8 increased with neutrophil infiltration, progressive bleeding and pulmonary oedema. Compared with BB group, sivelestat treatment decreased the NE activity and ameliorated the above indexes. CONCLUSION: Sivelestat, exerts a protective effect in lung injury after burn-blast combined injury through inhibiting NE activity to decrease pulmonary vascular permeability, neutrophil sequestration, and production of TNF-α and IL-8.

[Growth and migration of umbilical cord mesenchymal stem cells on polycarbonate membrane with different pore sizes].

OBJECTIVE: To observe the growth and migration of human umbilical cord mesenchymal stem cells (hUCMSCs) on polycarbonate membrane with different pore sizes and explore the criteria of selecting optimal Transwell insert for indirect co-culture to induce the differentiation of hUCMSCs. METHODS: hUCMSCs were isolated in vitro and then expanded in culture medium. After the treatment of mitomycin C, the cells were seeded on porous membranes of 6-well-dish Transwell inserts with different pore sizes of 0.4, 3.0 and 8.0 µm respectively. After culturing for 7 days, the cells were observed and counted on the bottom of each porous membrane. Then the calculation of migration ratio was performed. The growth and migration of hUCMSCs on porous membranes were also examined under scanning electron microscope (SEM). RESULTS: The migration ratios of hUCMSCs on membranes of 0.4, 3.0 and 8.0 µm pore sizes were 0, 1.8% and 8.0% respectively. The migration ratio of cells on 0.4 µm pore size membrane was statistically different from that of the other two pore size groups (P < 0.01). Under SEM, a small portion of cells were growing on the bottoms of membranes and moving through the pores. But there was no cell movement through 0.4 µm pore size membrane. CONCLUSIONS: hUCMSCs can migrate through the polycarbonate membranes of 3.0 µm and 8.0 µm pore sizes but not through the 0.4 µm one. Thus both sides of polycarbonate membrane of 0.4 µm pore size may be used for close indirect co-culture to induce the differentiation of hUCMSCs.

[Modulatory effect of insulin on scalded rat serum-induced apoptosis of skeletal myoblast].

OBJECTIVE: To study the modulatory effect of insulin on apoptosis of skeletal myoblast (L6 cells) by serum of scalded rat and its mechanism. METHODS: L6 cells cultured with DMEM medium containing 10% FBS were divided into control (C, added with 20% normal rat serum), serum from rat with scald injury (S, added with 20% serum from scalded rat), insulin (I, added with 20% normal rat serum and 100 nmol/L insulin), and serum of scalded rat + insulin (SI, added with 20% serum of scalded rat + 100 nmol/L insulin) groups according to the random number table. After being cultured for 48 hours, apoptosis was observed with Hoechst 33258 staining and its number counted, annexin V -FITC/PI double-labeling method was used to assess apoptosis rate, the protein levels of phosphorylated (p-) Akt, p-PI3K, Bax, Bcl-2, and active caspase-3 were determined by Western blotting. Data were processed with grouped or paired t test. RESULTS: (1) The amount of apoptosis with typical morphological change in S group [(59.6 +/- 3.9) per visual field] was more than that in C, I, and SI groups [(4.9 +/- 2.6), (5.5 +/- 2.1), (19.7 +/- 2.3) per visual field, with t value respectively 28.53, 29.86, 21.53, P values all below 0.01]. (2) Apoptotic rate in S group was (18.5 +/- 1.8)%, which was markedly higher than that in C, I, and SI groups [(1.1 +/- 0.6)%, (1.5 +/- 0.3)%, (7.8 +/- 0.6)%, with t value respectively 22.41, 22.83, 13.92, P values all below 0.01]. (3) Compared with those in C group, the protein levels of Bax and active caspase-3 in S group were up-regulated (1.12 +/- 0.63 vs. 0.16 +/- 0.03, 2.15 +/- 0.51 vs. 0.21 +/- 0.03, with t value respectively 3.80, 10.69, P values all below 0.01), the protein level of p-Akt was lowered (0.20 +/- 0.03 vs. 0.42 +/- 0.07, t = -8.46, P < 0.01), and the protein levels of p-PI3K and Bcl-2 showed no statistical difference (0.19 +/- 0.03 vs. 0.26 +/- 0.09, 0.17 +/- 0.03 vs. 0.28 +/- 0.07, with t value respectively -2.73, - 1.14, P values all above 0.05). The protein levels of Bax (0.40 +/- 0.14) and active caspase-3 (0.83 +/- 0.18) in SI group were lowered (t = -3.23, P < 0.05; t = 6.66, P < 0.01) and the protein levels of p-Akt, Bcl-2, and p-PI3K in SI group were elevated (0.39 +/- 0.10, 0.78 +/- 0.03, 0.47 +/- 0.12, with t value respectively 4.07, 18.71, 5.05, P < 0.05 or P < 0.01) as compared with those in S group. CONCLUSIONS: Serum from scalded rat can induce apoptosis in skeletal myoblast, and the effect can be inhibited by insulin through PI3K/Akt signal pathway.

[Early changes in serum neutrophil elastase in rats with burn, blast injury or combined burn-blast injury and its significance].

OBJECTIVE: To explore the early changes in serum neutrophil elastase (NE) in rats with burn, blast injury or combined burn-blast injury and its significance. METHODS: A total of 176 male Sprague Dawley rats were randomly divided into four groups: control (C), burn (BU), blast injury (BL) and burn-blast combined injury (BB). Rats in C group were not injured. Animals in BU group were subjected to 25% TBSA full-thickness burn on back with 94 degrees C water for 12 seconds; Animals in BL group were inflicted with moderate blast injury with 5 g 8701 compressed dynamite stick as the explosion source 75 cm away while left chest facing the explosive source; Rats in BB group were burned immediately after the blast injury similarly as in BL group. During the first 24 h post-injury, animals in BU and BB groups received intraperitoneal injection of sodium lactate Ringer's solution at a dose of 50 ml x kg(-1) x 12 h(-1). Protein concentration in bronchoalveolar lavage fluid (BALF), water content of lung tissue and NE content in serum were determined at 0 h (C group), 3 h, 6 h, 12 h, 1 d, 2 d, 3 d, 7 d post-injury. RESULTS: Protein concentration in BALF, water content of lung tissue and NE content in serum in SD rats of the injured groups were significantly higher than those in C group (P < 0.01 or P < 0.05), peaked within 2 d post-injury, especially at 2 d post-injury (NE content in serum: BU group, 319. 85 +/- 19.50 ng/ml; BL group, 467.43 +/- 31.64 ng/ml; BB group, 626.00 +/- 26.38 ng/ml vs. C group, 78.53 +/- 25.10 ng/ml). Overall, protein concentration in BALF, water content of lung tissue and NE content in serum in BB group were significantly higher than BU and BL groups (P < 0.01 or P < 0.05). Correlation analysis showed that within 3 d postinjury, a significant positive correlation was found between the protein concentration in BALF, water content of lung tissue and NE content in serum (r = 0.7910, 0.8078, P < 0.05) in BU group. NE content in serum and protein concentration in BALF were significantly positively correlated in BB group (r = 0.8672, P < 0.05). CONCLUSION: NE may play an important role in early lung injury of burn or blast injury, especially in combined burn-blast injury.

The effects and mechanisms of insulin on systemic inflammatory response and immune cells in severe trauma, burn injury, and sepsis.

Insulin resistance, hyperglycemia, inflammatory disorders and immune dysfunction cause high morbidity and mortality in patients with severe trauma, burn injuries, or sepsis. Many studies have shown that intensive insulin therapy can combat insulin resistance, decrease blood glucose levels, and induce anabolic processes, thus, decreasing morbidity and mortality. Moreover, in recent years, it has been proven that insulin can attenuate systemic inflammatory responses and modulate the proliferation, apoptosis, differentiation and immune functions of certain immune cells, especially monocytes/macrophages, neutrophils, and T cells associated with severe trauma, burn injury, or sepsis. This effect of insulin may expand our understanding of intensive insulin therapy in critically ill patients. This review attempts to summarize studies on the modulatory effects and mechanisms of insulin therapy on systemic inflammation and immune cells in severe trauma, burn injury and sepsis, and further propose some questions for future studies.

[Preparation and characterization of monoclonal antibodies against human CD112 (Nectin2/PRR2)].

AIM: To express and purify fusion protein of human CD112 extracellular region, prepare monoclonal antibodies (mAb) to CD112 and investigate the distribution of CD112 molecule. METHODS: The CD112-Fc fusion protein was expressed with gene recombinant technique in eukaryotic system and purified with affinity chromatography column. The BALB/c mice were immunized with purified CD112-Fc for preparation of mAb by hybridoma technique. The prepared mAbs were identified by indirect ELISA, Western blot and flow cytometry (FCM). Subsequently, the distribution of CD112 on different human cell lines was investigated by FCM. RESULTS: The effective expression plasmid pIg3C-CD112 was constructed, and human CD112-Fc was successfully expressed and purified with a purity of more than 90%. Nine clones of hybridoma were obtained, which were designated as FMU-CD112.1-FMU-CD112.9. FMU-CD112.1, 3, 6 and 8 specifically reacted with recombinant CD112-Fc protein in Western blot and FMU-CD112.1, 4, 6 and 8 could be used in FCM. The investigation of CD112 distribution showed high expression on the cell lines differentiated from epithelial cells. CONCLUSION: The hybridomas secreting mAbs to human CD112 are established successfully, which may lay the foundation for further research on the biological function of CD112.