Influence of reactive oxygen species responsive self-assembled nanomicelle loaded with pyroptosis inhibitor on full-thickness skin defects in diabetic rats / 中华烧伤杂志

Objective: To investigate the influence of reactive oxygen species (ROS) responsive self-assembled nanomicelle loaded with pyroptosis inhibitor on full-thickness skin defects in diabetic rats. Methods: Experimental research methods were employed. A nucleotide-binding oligomerization domain (NOD) 1/2 inhibitor (NOD-IN-1) was encapsulated with nanomicelle polyethylene glycol-block-polypropylene sulfide (PEG-b-PPS), and the resulting product was called PEPS@NOD-IN-1. The morphology and hydration particle size of PEG-b-PPS and PEPS@NOD-IN-1 were observed by transmission electron microscope and particle size analyzer, respectively, and the encapsulation rate and drug loading rate of PEPS@NOD-IN-1 to NOD-IN-1 and the cumulative release rate of NOD-IN-1 by PEPS@NOD-IN-1 in phosphate buffer solution (PBS) alone and hydrogen peroxide-containing PBS within 40 h were measured and calculated by microplate reader, and the sample number was 3. Twenty-four male Sprague-Dawley rats aged 6-7 weeks were injected with streptozotocin to induce type 1 diabetes mellitus. Six full-thickness skin defect wounds were made on the back of each rat. The injured rats were divided into PBS group, NOD-IN-1 group, PEG-b-PPS group, and PEPS@NOD-IN-1 group with corresponding treatment according to the random number table, with 6 rats in each group. The wound healing was observed on post injury day (PID) 3, 7, and 12, and the wound healing rate was calculated. The ROS levels in wound tissue were detected by immunofluorescence method on PID 3. On PID 7, the granulation tissue thickness in wound was assessed by hematoxylin-eosin staining, the mRNA expressions of NOD1 and NOD2 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction, and the protein expressions of NOD1, NOD2, and GSDMD-N terminals were detected by Western blotting. Six wounds from different rats in each group were taken for detection of the above indicators. Wound tissue (3 samples per group) was taken from rats in PBS group and PEPS@NOD-IN-1 group on PID 7, and transcriptome sequencing was performed using high-throughput sequencing technology platform. Differentially expressed genes (DEGs) significantly down-regulated in PEPS@NOD-IN-1 group as compared with PBS group were screened, and the enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) was performed. The DEG heatmap of the NOD-like receptor pathway, a pyroptosis-related pathway, was made. Protein-protein interaction (PPI) analysis of DEGs in heatmap was performed through the STRING database to screen key genes of PEPS@NOD-IN-1 regulating the NOD-like receptor pathway. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and Tukey test. Results: PEG-b-PPS and PEPS@NOD-IN-1 were in spherical structures of uniform size, with hydration particle sizes of (134.2±3.3) and (143.1±2.3) nm, respectively. The encapsulation rate of PEPS@NOD-IN-1 to NOD-IN-1 was (60±5)%, and the drug loading rate was (15±3)%. The release of NOD-IN-1 from PEPS@NOD-IN-1 in PBS alone was slow, and the cumulative release rate at 40 h was only (12.4±2.3)%. The release of NOD-IN-1 from PEPS@NOD-IN-1 in hydrogen peroxide-containing PBS within 10 h was very rapid, and the cumulative release rate at 10 h reached (90.1±3.6)%. On PID 3 and 7, the wounds of rats in the four groups were gradually healed, and the healing in PEPS@NOD-IN-1 group was better than that in the other three groups. On PID 12, the wound scab area in PBS group was large, the wound epithelialization in NOD-IN-1 group and PEG-b-PPS group was obvious, and the wound in PEPS@NOD-IN-1 group was close to complete epithelialization. Compared with those in PBS group, NOD-IN-1 group, and PEG-b-PPS group, the wound healing rates on PID 7 and 12 in PEPS@NOD-IN-1 group were significantly increased (P<0.05), the level of ROS in wound tissue on PID 3 was significantly decreased (P<0.05), the thickness of granulation tissue in wound on PID 7 was significantly thickened (P<0.05), and the mRNA expressions of NOD1 and NOD2 and the protein expressions of NOD1, NOD2, and GSDMD-N terminals in wound tissue on PID 7 were significantly decreased (P<0.05). KEGG pathway analysis showed that DEGs significantly down-regulated in PEPS@NOD-IN-1 group as compared with PBS group were significantly enriched in NOD-like receptors, hypoxia-inducible factors, mitogen-activated protein kinases, and tumor necrosis factor (TNF) pathways. In the DEG heatmap of NOD-like receptor pathway, the genes regulating pyroptosis mainly involved NOD1, NOD2, NOD-like receptor thermoprotein domain-related protein 3, Jun, signal transduction and transcriptional activator 1 (STAT1), TNF-α-induced protein 3. The PPI results showed that NOD1, NOD2, and STAT1 were the key genes of PEPS@NOD-IN-1 regulating the NOD-like receptor pathway. Conclusions: PEPS@NOD-IN-1 can down-regulate the level of local ROS in wounds and the expression of NOD1, NOD2, and GSDMD-N terminals, the key regulators of pyroptosis, thereby promoting the repair of full-thickness skin defect wounds in diabetic rats. PEPS@NOD-IN-1 can also significantly down-regulate the pyroptosis, inflammation, and hypoxia-related pathways of wounds, and regulate NOD-like receptor pathways by down-regulating key genes NOD1, NOD2, and STAT1.

Effects of interleukin-4-modified gold nanozymes on the full-thickness skin defects in diabetic mice / 中华烧伤杂志

Objective: To investigate the effects and mechanism of interleukin-4-modified gold nanoparticle (IL-4-AuNP) on the wound healing of full-thickness skin defects in diabetic mice. Methods: Experimental research methods were adopted. Gold nanoparticle (AuNP) and IL-4-AuNP were synthesized by improving the methods described in published literature. The morphology of those two particles were photographed by transmission electron microscopy, and their particle sizes were calculated. The surface potential and hydration particle size of the two particles were detected by nanoparticle potentiometer and particle size analyzer, respectively. The clearance rate of IL-4-AuNP to hydrogen peroxide and superoxide anion was measured by hydrogen peroxide and superoxide anion kits, respectively. Mouse fibroblast line 3T3 cells were used and divided into the following groups by the random number table (the same below): blank control group, hydrogen peroxide alone group treated with hydrogen peroxide only, hydrogen peroxide+IL-4-AuNP group treated with IL-4-AuNP for 0.5 h and then treated with hydrogen peroxide. After 24 h of culture, the reactive oxygen species (ROS) levels of cells were detected by immunofluorescence method; cell count kit 8 was used to detect relative cell survival rate. The macrophage Raw264.7 mouse cells were then used and divided into blank control group and IL-4-AuNP group that treated with IL-4-AuNP. After 24 h of culture, the expression of arginase 1 (Arg-1) in cells was observed by immunofluorescence method. Twelve male BALB/c mice (mouse age, sex, and strain, the same below) aged 8 to 10 weeks were divided into IL-4-AuNP group and blank control group, treated accordingly. On the 16th day of treatment, whole blood samples were collected from mice for analysis of white blood cell count (WBC), red blood cell count (RBC), hemoglobin level, or platelet count and the level of aspartate aminotransferase (AST), alanine transaminase (ALT), urea, or creatinine. The inflammation, bleeding, or necrosis in the heart, liver, spleen, lung, and kidney tissue of mice were detected by hematoxylin-eosin (HE). Another 36 mice were selected to make diabetic model, and the full-thickness skin defect wounds were made on the back of these mice. The wounds were divided into blank control group, AuNP alone group, and IL-4-AuNP group, with 12 mice in each group, and treated accordingly. On the 0 (immediately), 4th, 9th, and 15th day of treatment, the wound condition was observed and the wound area was calculated. On the 9th day of treatment, HE staining was used to detect the length of neonatal epithelium and the thickness of granulation tissue in the wound. On the 15th day of treatment, immunofluorescence method was used to detect ROS level and the number of Arg-1 positive cells in the wound tissue. The number of samples was 6 in all cases. Data were statistically analyzed with independent sample t test, corrected t test, Tukey test, or Dunnett T3 test. Results: The size of prepared AuNP and IL-4-AuNP were uniform. The particle size, surface potential, and hydration particle size of AuNP and IL-4-AuNP were (13.0±2.1) and (13.9±2.5) nm, (-45.8±3.2) and (-20.3±2.2) mV, (14±3) and (16±4) nm, respectively. For IL-4-AuNP, the clearance rate to hydrogen peroxide and superoxide anion were (69±4)% and (52±5)%, respectively. After 24 h of culture, the ROS level of 3T3 in hydrogen peroxide alone group was significantly higher than that in blank control group (q=26.12, P<0.05); the ROS level of hydrogen peroxide+IL-4-AuNP group was significantly lower than that in hydrogen peroxide alone group (q=25.12, P<0.05) and close to that in blank control group (P>0.05). After 24 h of culture, the relative survival rate of 3T3 cells in hydrogen peroxide+IL-4-AuNP group was significantly higher than that in hydrogen peroxide alone group (t=51.44, P<0.05). After 24 h of culture, Arg-1 expression of Raw264.7 cells in IL-4-AuNP group was significantly higher than that in blank control group (t'=8.83, P<0.05).On the 16th day of treatment, there were no significant statistically differences in WBC, RBC, hemoglobin level, or platelet count and the level of AST, ALT, urea, or creatinine of mice between blank control group and IL-4-AuNP group (P>0.05). No obvious inflammation, bleeding or necrosis was observed in the heart, liver, spleen, lung, and kidney of important organs in IL-4-AuNP group, and no significant changes were observed compared with blank control group. On the 0 and 4th day of treatment, the wound area of diabetic mice in blank control group, AuNP alone group, and IL-4-AuNP group had no significant difference (P>0.05). On the 9th day of treatment, the wound areas both in AuNP alone group and IL-4-AuNP group were significantly smaller than that in blank control group (with q values of 9.45 and 14.87, respectively, P<0.05), the wound area in IL-4-AuNP group was significantly smaller than that in AuNP alone group (q=5.42, P<0.05). On the 15th day of treatment, the wound areas both in AuNP alone group and IL-4-AuNP group were significantly smaller than that in blank control group (with q values of 4.84 and 20.64, respectively, P<0.05), the wound area in IL-4-AuNP group was significantly smaller than that in AuNP alone group (q=15.80, P<0.05); moreover, inflammations such as redness and swelling were significantly reduced in IL-4-AuNP group compared with the other two groups. On the 9th day of treatment, compared with blank control group and AuNP alone group, the length of neonatal epithelium in the wound of diabetic mice in IL-4-AuNP group was significantly longer (all P<0.05), and the thickness of the granulation tissue in the wound was significantly increased (with q values of 11.33 and 9.65, respectively, all P<0.05). On the 15th day of treatment, compared with blank control group, ROS levels in wound tissue of diabetic mice in AuNP alone group and IL-4-AuNP group were significantly decreased (P<0.05). On the 15th day of treatment, the number of Arg-1 positive cells in the wounds of diabetic mice in IL-4-AuNP group was significantly more than that in blank control group and AuNP alone group, respectively (all P<0.05). Conclusions: IL-4-AuNP is safe in vivo, and can improve the oxidative microenvironment by removing ROS and induce macrophage polarization towards M2 phenotype, thus promote efficient diabetic wound healing and regeneration of full-thickness skin defects in diabetic mice.

Role of functional hydrogel in promoting wound healing / 中华烧伤杂志

Cutaneous wounds are one of the commonest clinical diseases. At present, there are still many challenges in how to repair wounds quickly with high quality. With the rapid development and cross-integration of materials science and biomedicine, hydrogels that can integrate various excellent properties through flexible structural modification and combination of different functional components are widely applied in wound management and research. This paper attempted to summarize the role of hydrogel in promoting wound repair from the respects of matrix materials, special structures, and diverse functions of hydrogel.

Effects of P311 on the angiogenesis ability of human microvascular endothelial cell 1 in vitro and its molecular mechanism / 中华烧伤杂志

Objective: To explore the effects of P311 on the angiogenesis ability of human microvascular endothelial cell 1 (HMEC-1) in vitro and the potential molecular mechanism. Methods: The experimental research method was used. HMEC-1 was collected and divided into P311 adenovirus group and empty adenovirus group according to the random number table (the same grouping method below), which were transfected correspondingly for 48 h. The cell proliferation activity was detected using the cell counting kit 8 on 1, 3, and 5 days of culture. The residual scratch area of cells at post scratch hour 6 and 11 was detected by scratch test, and the percentage of the residual scratch area was calculated. The blood vessel formation of cells at 8 h of culture was observed by angiogenesis experiment in vitro, and the number of nodes and total length of the tubular structure were measured. The protein expressions of vascular endothelial growth factor receptor 2 (VEGFR2), phosphorylated VEGFR2 (p-VEGFR2), extracellular signal-regulated kinase 1/2 (ERK1/2), and phosphorylated ERK1/2 (p-ERK1/2) in cells were detected by Western blotting. HMEC-1 was collected and divided into P311 adenovirus+small interfering RNA (siRNA) negative control group, empty adenovirus+siRNA negative control group, P311 adenovirus+siRNA-VEGFR2 group, and empty adenovirus+siRNA-VEGFG2 group, which were treated correspondingly. The protein expressions of VEGFR2, p-VEGFR2, ERK1/2, and p-ERK1/2 in cells were detected by Western blotting at 24 h of transfection. The blood vessel formation of cells at 24 h of transfection was observed by angiogenesis experiment in vitro, and the number of nodes and total length of the tubular structure were measured. HMEC-1 was collected and divided into P311 adenovirus+dimethylsulfoxide (DMSO) group, empty adenovirus+DMSO group, P311 adenovirus+ERK1/2 inhibitor group, and empty adenovirus+ERK1/2 inhibitor group, which were treated correspondingly. The protein expressions of ERK1/2 and p-ERK1/2 in cells were detected by Western blotting at 2 h of treatment. The blood vessel formation of cells at 2 h of treatment was observed by angiogenesis experiment in vitro, and the number of nodes and total length of the tubular structure were measured. The sample number at each time point in each group was 6. Data were statistically analyzed with independent sample t test, analysis of variance for repeated measurement, one-way analysis of variance, and least significant difference test. Results: Compared with that of empty adenovirus group, the proliferation activity of cells in P311 adenovirus group did not show significant difference on 1, 3, and 5 days of culture (with t values of -0.23, -1.30, and -1.52, respectively, P>0.05). The residual scratch area percentages of cells in P311 adenovirus group were significantly reduced at post scratch hour 6 and 11 compared with those of empty adenovirus group (with t values of -2.47 and -2.62, respectively, P<0.05). At 8 h of culture, compared with those of empty adenovirus group, the number of nodes and total length of the tubular structure of cells in P311 adenovirus group were significantly increased (with t values of 4.49 and 4.78, respectively, P<0.01). At 48 h of transfection, compared with those of empty adenovirus group, the protein expressions of VEGFR2 and ERK1/2 of cells in P311 adenovirus group showed no obvious changes (P>0.05), and the protein expressions of p-VEGFR2 and p-ERK1/2 of cells in P311 adenovirus group were significantly increased (with t values of 17.27 and 16.08, P<0.01). At 24 h of transfection, the protein expressions of p-VEGFR2 and p-ERK1/2 of cells in P311 adenovirus+siRNA negative control group were significantly higher than those in empty adenovirus+siRNA negative control group (P<0.01). The protein expressions of VEGFR2, p-VEGFR2, and p-ERK1/2 of cells in P311 adenovirus+siRNA negative control group were significantly higher than those in P311 adenovirus+siRNA-VEGFR2 group (P<0.01). The protein expressions of VEGFR2 and p-ERK1/2 of cells in empty adenovirus+siRNA negative control group were significantly higher than those in empty adenovirus+siRNA-VEGFR2 group (P<0.05 or P<0.01). At 24 h of transfection, the number of nodes of the tubular structure in cells of P311 adenovirus+siRNA negative control group was 720±62, which was significantly more than 428±38 in empty adenovirus+siRNA negative control group and 364±57 in P311 adenovirus+siRNA-VEGFR2 group (with P values both <0.01). The total length of the tubular structure of cells in P311 adenovirus+siRNA negative control group was (21 241±1 139) μm, which was significantly longer than (17 005±1 156) μm in empty adenovirus+siRNA negative control group and (13 494±2 465) μm in P311 adenovirus+siRNA-VEGFR2 group (with P values both <0.01). The number of nodes of the tubular structure in cells of empty adenovirus+siRNA negative control group was significantly more than 310±75 in empty adenovirus+siRNA-VEGFR2 group (P<0.01), and the total length of the tubular structure of cells in empty adenovirus+siRNA negative control group was significantly longer than (11 600±2 776) μm in empty adenovirus+siRNA-VEGFR2 group (P<0.01). At 2 h of treatment, the protein expression of p-ERK1/2 of cells in P311 adenovirus+DMSO group was significantly higher than that in empty adenovirus+DMSO group and P311 adenovirus+ERK1/2 inhibitor group (with P values both <0.01), and the protein expression of p-ERK1/2 of cells in empty adenovirus+DMSO group was significantly higher than that in empty adenovirus+ERK1/2 inhibitor group (P<0.05). At 2 h of treatment, the number of nodes of the tubular structure in cells of P311 adenovirus+DMSO group was 726±72, which was significantly more than 421±39 in empty adenovirus+DMSO group and 365±41 in P311 adenovirus+ERK1/2 inhibitor group (with P values both <0.01). The total length of the tubular structure of cells in P311 adenovirus+DMSO group was (20 318±1 433) μm, which was significantly longer than (16 846±1 464) μm in empty adenovirus+DMSO group and (15 114±1 950) μm in P311 adenovirus+ERK1/2 inhibitor group (with P values both <0.01). The number of nodes of the tubular structure in cells of empty adenovirus+DMSO group was significantly more than 317±67 in empty adenovirus+ERK1/2 inhibitor group (P<0.01), and the total length of the tubular structure of cells in empty adenovirus+DMSO group was significantly longer than (13 188±2 306) μm in empty adenovirus+ERK1/2 inhibitor group (P<0.01). Conclusions: P311 can enhance the angiogenesis ability of HMEC-1 by activating the VEGFR2/ERK1/2 signaling pathway.

Continuing the brilliance in response to the development trend of discipline: congratulations on the publication of Chinese Journal of Burns and Wounds / 中华烧伤杂志

At the beginning of 2022, the first issue of the renamed journal-Chinese Journal of Burns and Wounds is published successfully, the editor-in-chief, Prof. Gaoxing Luo, explains the purpose, reason and necessity in the frontispiece to change the name of the journal from Chinese Journal of Burns to Chinese Journal of Burns and Wounds. Meanwhile, the unshakable and authoritative academic function and position of the journal in the discipline of burns not only in China but also in the world is illustrated. In fact, wound repair and regeneration is one of the most important and skillful tasks for burn experts, which has been also the main published content of the journal since it was founded in 2000. In order to meet the needs of the development of the discipline of burns and wounds and to make the name of the journal much more consistent with the published content, the journal is renamed as the new one without any changes of aim or scope of the publication. We believe that the journal with the new name will grow better and faster, and will set up a much more valuable academic platform for the development and talent cultivation for the disciplines of burns and wounds in the future.

Application effects of bundle nursing of citric acid extracorporeal anticoagulation on continuous renal replacement therapy of severe burn patients / 中华烧伤杂志

Objective: To explore the application effects of bundle nursing of citric acid extracorporeal anticoagulation on continuous renal replacement therapy (CRRT) of severe burn patients. Methods: A non-randomized controlled study was conducted. Forty-six patients who met the inclusion criteria and received regular nursing of citric acid extracorporeal anticoagulation during CRRT in the First Affiliated Hospital of Army Medical University (the Third Military Medical University) from January to December 2017 were included in regular nursing group (30 males and 16 females, aged 42.0 (38.7,47.0) years, with 201 times of CRRT performed), and 48 patients who met the inclusion criteria and received bundle nursing of citric acid extracorporeal anticoagulation during CRRT in the same hospital from January to December 2018 were included in bundle nursing group (32 males and 16 females, aged 41.0 (36.0,46.0) years, with 164 times of CRRT performed). The clinical data of all the patients in the two groups were recorded, including the length of intensive care unit (ICU) stay, total cost of treatment in ICU, cost of CRRT, unplanned ending of treatment, ending of treatment due to operation (with the rates of unplanned ending of treatment and ending of treatment due to operation calculated), times of disposable hemodialysis filter and supporting pipeline filter (hereinafter referred to as filter) with use time>24 h, times of CRRT, and lifetime of filter. For the patients in both groups who continuously received CRRT for 3 days or more from the first treatment, the prothrombin time (PT), activated partial thromboplastin time (APTT), international normalized ratio (INR), total calcium, ionic calcium (with the difference of total calcium or ionic calcium between before and after treatment calculated), creatinine, urea, β2 microglobulin, cystatin C, platelet count, mean arterial pressure, pH value, oxygenation index, bicarbonate radical, and lactic acid levels before the first treatment (hereinafter referred to as before treatment) and 3 days after the first treatment (hereinafter referred to as after 3 days of treatment). The treatment-related complications of all patients in the two groups were recorded during hospitalization. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, and chi-square test. Results: Compared with those in regular nursing group, the length of ICU stay was significantly shortened (Z=-4.71, P<0.01), the total cost of treatment in ICU was significantly reduced (t=-1.39, P<0.01), the cost of CRRT had no significant change (P>0.05), the rates of unplanned ending of treatment and ending of treatment due to operation were both significantly decreased (with χ2 values of 12.20 and 17.83, respectively, P<0.01), the times of filter service time>24 h was increased significantly (Z=-5.93, P<0.01), the times of CRRT were significantly reduced (Z=-4.75, P<0.01), and the filter service life was significantly prolonged (Z=-9.24, P<0.01) among patients in bundle nursing group. Thirty-one patients in bundle nursing group and 28 patients in regular nursing group continuously received CRRT for 3 days or more from the first treatment. Before treatment, PT, APTT, and INR of patients in bundle nursing group were 24.10 (16.08, 39.20) s, 38.81 (32.32, 45.50) s, and 1.17 (1.12, 1.19), respectively, similar to 31.75 (22.99, 40.96) s, 41.82 (35.05, 48.06) s, and 1.15 (1.11, 1.19) of patients in regular nursing group (P>0.05); the levels of total calcium and ionic calcium of patients in the two groups were similar (P>0.05). After 3 days of treatment, PT, APTT, and INR of patients in bundle nursing group and regular nursing group were 29.06 (20.11, 39.46) s, 35.25 (30.06, 40.28) s, 1.13 (1.09, 1.17) and 36.51 (26.64, 42.92) s, 39.89 (34.81, 46.62) s, 1.14 (1.10, 1.18), respectively, similar to those before treatment (P>0.05); the level of ionic calcium of patients in regular nursing group was significantly higher than that before treatment (Z=-2.08, P<0.05); the levels of total calcium and ionic calcium of patients in bundle nursing group were both significantly higher than those before treatment (with Z values of -3.55 and -3.69, respectively, P<0.01); compared with those in regular nursing group, APTT of patients was significantly shorter (Z=-2.29, P<0.05), while the total calcium level of patients was significantly higher in bundle nursing group (Z=-2.26, P<0.05). The difference of total calcium between before and after treatment of patients in bundle nursing group was significantly higher than that in regular nursing group (Z=-3.15, P<0.01). The differences of ionic calcium between before and after treatment of patients in the two groups were similar (P>0.05). Before treatment, the level of β2 microglobulin of patients in bundle nursing group was significantly higher than that in regular nursing group (Z=-2.84, P<0.01), the platelet count of patients in bundle nursing group was significantly lower than that in regular nursing group (Z=-2.44, P<0.05), while the levels of creatinine, urea, cystatin C, mean arterial pressure, pH value, oxygenation index, bicarbonate radical, and lactic acid of patients in the two groups were similar (P>0.05). After 3 days of treatment, the levels of creatinine, urea, β2 microglobulin, cystatin C, pH value, bicarbonate radical, and lactic acid of patients were all significantly lower than those before treatment (with Z values of -2.10, -2.90, -3.11, -2.02, -2.34, -2.63, and -2.84, respectively, P<0.05 or P<0.01), while the levels of platelet count, oxygenation index, and mean arterial pressure of patients were all significantly higher than those before treatment in bundle nursing group (with Z values of -6.65 and -2.40, respectively, t=-9.97, P<0.05 or P<0.01); the levels of creatinine, urea, β2 microglobulin, cystatin C, platelet count, pH value, bicarbonate radical, and lactic acid of patients were all significantly lower than those before treatment (with Z values of -5.32, -2.31, -2.41, -2.21, -3.68, -2.93, -2.20, and -2.31, respectively, P<0.05 or P<0.01), while the oxygenation index and mean arterial pressure of patients were both significantly higher than those before treatment in regular nursing group (Z=-5.59, t=-7.74, P<0.01). After 3 days of treatment, compared with those in regular nursing group, the levels of creatinine, cystatin C, platelet count, oxygenation index, bicarbonate radical, and mean arterial pressure of patients were all significantly higher (with Z values of -2.93, -1.99, -6.39, -2.09, and -2.52, respectively, t=-3.28, P<0.05 or P<0.01), while the levels of urea, β2 microglobulin, pH value, and lactic acid of patients were all significantly lower (with Z values of -3.87, -2.58, -4.24, and -2.75, respectively, P<0.05 or P<0.01) in bundle nursing group. During hospitalization, there were no treatment-related bleeding events or hypernatremia related to citric acid treatment of patients in the two groups. The ratio of total calcium to ionic calcium in one patient in bundle nursing group was >2.5, but there was no manifestation of citric acid accumulation poisoning; 1 patient had hypoionic calcemia, and 1 patient had severe metabolic alkalosis. Five patients had hypoionic calcemia and 2 patients had severe metabolic alkalosis in regular nursing group. Conclusions: The implementation of bundle nursing of citric acid extracorporeal anticoagulation during CRRT for severe burn patients shortens the length of ICU stay, reduces the total cost of treatment in ICU and the occurrence of treatment-related complications, relieves the economic burden of patients, and improves the continuity and quality of treatment.

Effects of porcine acellular dermal matrix combined with human epidermal stem cells on wound healing of full-thickness skin defect in nude mice / 中华烧伤杂志

Objective: To explore the effects of porcine acellular dermal matrix (ADM) combined with human epidermal stem cells (ESCs) on wound healing of full-thickness skin defect in nude mice. Methods: The morphology of porcine ADM was analyzed by photograph of digital camera, the cell residues in porcine ADM were observed by hematoxylin-eosin (HE) staining, the surface structure of porcine ADM was observed by scanning electron microscope, the secondary structure of porcine ADM was analyzed by infrared spectrometer, the porcine ADM particle size was analyzed by dynamic light scattering particle size analyzer, and the porcine ADM potential was analyzed by nano-particle size potentiometer. The morphology of porcine ADM was observed by inverted fluorescence microscope when it was placed in culture medium for 30 min, 1 d, and 5 d (n=2). The porcine ADM was divided into 5 min group, 10 min group, 20 min group, 30 min group, 60 min group, and 120 min group according to the random number table (the same grouping method below) in static state at normal temperature for the corresponding time to calculate the water absorption by weighing method (n=3). Swiss white mouse embryonic fibroblasts (Fbs) were divided into blank control group (culture medium only), and 50.0 g/L ADM extract group, 37.5 g/L ADM extract group, 25.0 g/L ADM extract group, 12.5 g/L ADM extract group, and 6.5 g/L ADM extract group which were added with the corresponding final concentrations of ADM extract respectively. At post culture hour (PCH) 24, 48, and 72, the cell survival rate was detected by cell counting kit 8 and the cytotoxicity was graded (n=5). The erythrocytes of a 6-week-old male Sprague-Dawley male rat were divided into normal saline group, ultra-pure water group, and 5 mg/mL ADM extract group, 10 mg/mL ADM extract group, and 15 mg/mL ADM extract group which were treated with the corresponding final concentrations of porcine ADM extract respectively. After reaction for 3 h, the absorbance value of hemoglobin was detected by microplate reader to represent the blood compatibility of porcine ADM (n=3). ESCs were isolated and cultured from the discarded prepuce of a 6-year-old healthy boy who was treated in the Department of Urology of the First Affiliated Hospital of Army Medical University (the Third Military Medical University) in July 2020, and then identified by flow cytometry. The porcine ADM particles of composite ESC (hereinafter referred to as ESC/ADM) were constructed by mixed culture. After 3 days of culture, the composite effect of ESC/ADM was observed by HE staining and laser scanning confocal microscope. Thirty-six 7-8-week-old male non-thymic nude mice were divided into phosphate buffer solution (PBS) alone group, ADM alone group, ESC alone group, and ESC/ADM group, with 9 mice in each group, and the wound model of full-thickness skin defect was established. Immediately after injury, the wounds were treated with the corresponding reagents at one time. On post injury day (PID) 1, 7, 11, and 15, the wound healing was observed and the wound healing rate was counted (n=3). On PID 7, the epithelialization of wounds was observed by HE staining and the length of un-epithelialized wound was measured (with this and the following sample numbers of 4). On PID 11, the dermal area and collagen deposition of wounds were observed by Masson staining and the dermal area of wound section was calculated, the number of cells expressing CD49f, a specific marker of ESC, was calculated with immunofluorescence staining, the mRNA expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in ESC after wound transplantation was detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction. Data were statistically analyzed with independent sample t test, one-way analysis of variance, analysis of variance for repeated measurement, and least significant difference t test. Results: The porcine ADM was white particles and composed of reticular structure, with no cells inside, disordered structure, and rough surface. The absorption peak of porcine ADM appeared at the wave numbers of 1 659, 1 549, and 1 239 cm-1, respectively. The main particle size distribution of porcine ADM in solution was 500 to 700 nm, with negative charge on the surface. The morphology of porcine ADM in static state at 30 min and on 1 and 5 d was relatively stable. The water absorption of porcine ADM remained relatively high level in static state from 30 min to 120 min. The cytotoxicity of mouse embryonic Fbs in 6.5 g/L ADM extract group, 12.5 g/L ADM extract group, and 25.0 g/L ADM extract group was grade 1 at PCH 24, and the cytotoxicity of the other groups was 0 grade at each time point. After reaction for 3 h, the absorbance value of hemoglobin of erythrocytes in ultra-pure water group was significantly higher than the values in normal saline group and 15 mg/mL ADM extract group (with t values of 8.14 and 7.96, respectively, P<0.01). After 3 days of culture, the cells of the fourth passage showed pebble-like morphology, with low expression of CD71 and high expression of CD49f, which were identified as ESCs. There was ESC attachment and growth on porcine ADM particles. On PID 1, the wound sizes of nude mice were almost the same in PBS alone group, ADM alone group, ESC alone group, and ESC/ADM group. On PID 7, 11, and 15, the wound contraction of nude mice in each group was observed, especially in ADM alone group, ESC alone group, and ESC/ADM group. On PID 7, the wound healing rates of nude mice in ESC alone group and ESC/ADM group were significantly higher than the rate in PBS alone group (with t values of 2.83 and 4.72 respectively, P<0.05 or P<0.01). On PID 11, the wound healing rate of nude mice in ESC/ADM group was significantly higher than that in PBS alone group (t=4.86, P<0.01). On PID 15, the wound healing rates of nude mice in ADM alone group, ESC alone group, and ESC/ADM group were significantly higher than the rate in PBS alone group (with t values of 2.71, 2.90, and 3.23 respectively, P<0.05). On PID 7, the length of un-epithelialized wound of nude mice in ADM alone group, ESC alone group, and ESC/ADM group was (816±85), (635±66), and (163±32) μm, respectively, which were significantly shorter than (1 199±43) μm in PBS alone group (with t values of 5.69, 10.19, and 27.54 respectively, P<0.01). On PID 11, the dermal areas of wound section of nude mice in ADM alone group, ESC alone group, and ESC/ADM group were significantly larger than the area in PBS alone group (with t values of 27.14, 5.29, and 15.90 respectively, P<0.01); the collagen production of nude mice in ADM alone group and ESC/ADM group was more obvious than that in PBS alone group, and the collagen production of nude mice in ESC alone group and PBS alone group was similar. On PID 11, in the wounds of nude mice in ESC alone group and ESC/ADM group, the cells with positive expression of CD49f were respectively 135±7 and 185±15, and the mRNA expressions of GAPDH were positive; while there were no expressions of CD49f nor mRNA of GAPDH in the wounds of nude mice in PBS alone group and ADM alone group. Conclusions: ESC/ADM particles can promote the wound healing of full-thickness skin defects in nude mice, which may be related to the improved survival rate of ESCs after transplantation and the promotion of dermal structure rearrangement and angiogenesis by ADM.

Process of Hypertrophic Scar Formation: Expression of Eukaryotic Initiation Factor 6 / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Hypertrophic scar is one of the most common complications and often causes the disfigurement or deformity in burn or trauma patients. Therapeutic methods on hypertrophic scar treatment have limitations due to the poor understanding of mechanisms of hypertrophic scar formation. To throw light on the molecular mechanism of hypertrophic scar formation will definitely improve the outcome of the treatment. This study aimed to illustrate the negative role of eukaryotic initiation factor 6 (eIF6) in the process of human hypertrophic scar formation, and provide a possible indicator of hypertrophic scar treatment and a potential target molecule for hypertrophic scar.</p><p><b>METHODS</b>In the present study, we investigated the protein expression of eIF6 in the human hypertrophic scar of different periods by immunohistochemistry and Western blot analysis.</p><p><b>RESULTS</b>In the hypertrophic scar tissue, eIF6 expression was significantly decreased and absent in the basal layer of epidermis in the early period, and increased slowly and began to appear in the basal layer of epidermis by the scar formation time.</p><p><b>CONCLUSIONS</b>This study confirmed that eIF6 expression was significantly related to the development of hypertrophic scar, and the eIF6 may be a target molecule for hypertrophic scar control or could be an indicator of the outcomes for other treatment modalities.</p>

Multi-center clinical trial of FLAMIGEL (hydrogel dressing) for the treatment of residual burn wound / 中华烧伤杂志

<p><b>OBJECTIVE</b>To evaluate the effect of FLAMIGEL (hydrogel dressing) on the repair of residual burn wound.</p><p><b>METHODS</b>Sixty burn patients with residual wounds hospitalized in 6 burn units from November 2011 to May 2012 were enrolled in the multi-center, randomized, and self-control clinical trial. Two residual wounds of each patient were divided into groups T (treated with FLAMIGEL) and C (treated with iodophor gauze) according to the random number table. On post treatment day (PTD) 7 and 14, wound healing rate was calculated, with the number of completely healed wound counted. The degree of pain patient felt during dressing change was evaluated using the visual analogue scale (VAS). The mean numbers of wounds with score equal to zero, more than zero and less than or equal to 3, more than 3 and less than or equal to 6, more than 6 and less than or equal to 10 were recorded respectively. Wound secretion or exudate samples were collected for bacterial culture, and the side effect was observed. Data were processed with repeated measure analysis of variance, t test, chi-square test, and nonparametric rank sum test.</p><p><b>RESULTS</b>Wound healing rate of groups T, C on PTD 7 was respectively (67 ± 24)%, (45 ± 25)%, and it was respectively (92 ± 16)%, (72 ± 23)% on PTD 14. There was statistically significant difference in wound healing rate on PTD 7, 14 between group T and group C (F = 32.388, P < 0.01). Ten wounds in group T and four wounds in group C were healed completely on PTD 7, with no significant difference between them (χ(2) = 0, P > 0.05). Forty-two wounds in group T and seven wounds in group C healed completely on PTD 14, with statistically significant difference between them (χ(2) = 42.254, P < 0.01). Patients in group T felt mild pain during dressing change for 37 wounds, with VAS score higher than zero and lower than or equal to 3. Evident pain was observed in patients of group C during dressing change for 43 wounds, and it scored higher than 3 and less than or equal to 6 by VAS evaluation. There was statistically significant difference in mean number of wounds with different grade of VAS score between group T and group C (Z = -4.638, P < 0.01). Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, E. coli, Baumanii, and Staphylococcus epidermidis were all detected in both groups, but there was no statistical difference between group T and group C (χ(2) = 0.051, P > 0.05). No side effect was observed in either of the two groups during the whole trial.</p><p><b>CONCLUSIONS</b>FLAMIGEL can accelerate the healing of residual burn wounds and obviously relieve painful sensation during dressing change.</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.

Biologic effect of nitric oxide on human epidermal stem cells in vitro / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the effect of nitric oxide (NO) on adhesion, proliferation, and migration of human epidermal stem cells (ESC) in vitro.</p><p><b>METHODS</b>ESC were isolated and cultured by the modified method of rapid attachment to type IV collagen. (1) Morphology of cells was observed under inverted phase-contrast microscope. Expression levels of integrin β(1) and cytokeratin 19 (CK19) of cells were determined by Western blotting and immunofluorescence staining. (2) After being treated with scratching, ESC adhered to the wall was respectively treated with nitric oxide (NO) donor S-nitroso-N-acetylpenicillamine (SNAP) in the concentration of 1, 10, 100, 500 µmol/L. ESC without treatment of SNAP was used as control. The migration rate of ESC was detected at post scratching hour (PSH) 12 and 24. The chemotaxis of ESC (treated with SNAP in above-mentioned concentration) was tested by Transwell assay, and the transferred cell number was counted. (3) ESC was respectively treated with SNAP in the concentration of 10, 100, 500 µmol/L for 1 h. ESC without treatment of SNAP was used as control. The adhesion of ESC was detected with adhesion test, and the inhibition rate of adhesion was calculated. The proliferation of ESC (denoted as absorbance value) was determined by microplate reader at post-treatment hour (PTH) 0, 12, 24, 48. Data were processed with one-way analysis of variance and Dunnett t test.</p><p><b>RESULTS</b>(1) Small clone formed on post culture days (PCD) 5 to 9. On PCD 10 to 14, cell proliferation sped up. CK19 and integrin β(1) were detected to be expressed in the isolated cells. The cells were identified as ESC. (2) Compared with that of ESC without treatment of SNAP [(35.7 ± 0.3)%, (45.7 ± 5.0)%], migration of ESC treated with SNAP in the concentration from 1 to 100 µmol/L was promoted at PSH 12 and 24. Migration rates of ESC treated with 100 µmol/L SNAP were the highest [respectively (48.8 ± 2.7)%, (82.1 ± 15.8)%, with t value respectively 8.34, 5.10, P values both below 0.01]. The number of ESC transferred to membrane after being treated with 100 µmol/L SNAP was significantly larger than that of ESC without treatment of SNAP (t = 9.24, P = 0.00). (3) Absorbance values of ESC treated with 100, 500 µmol/L SNAP were obviously higher than that of ESC without treatment of SNAP (with t value respectively 4.30, 4.67, P values both equal to 0.00). Proliferation of ESC treated with 100, 500 µmol/L SNAP was obviously stronger than that of cells without treatment of SNAP at PTH 24, 48 (with t values from 2.84 to 8.17, P values all below 0.05).</p><p><b>CONCLUSIONS</b>Exogenous NO in suitable concentration can promote the migration of human ESC. Exogenous NO can inhibit the adhesion and promote the proliferation of human ESC in vitro.</p>

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>

Effects of P 311 on the migration of epidermal stem cells in mice with superficial partial-thickness burn and injured cell model in vitro / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study effects of P311 on the migration of epidermal stem cells (ESCs) in mice with superficial partial-thickness burn and injured cell model in vitro and to explore the mechanism.</p><p><b>METHODS</b>(1) Eighteen male C(57) BL/6 mice were used. Fifteen of them were inflicted with superficial partial-thickness burn on the back. In three injured mice wound tissue and skin of wound edge were obtained at post burn hour (PBH) 6, 12, 24, 48, 72 respectively. The rest three mice were used as normal control, and samples were harvested with the same method as above. The expressions of P311 in harvested samples were assessed with biotin-streptavidin-peroxidase (SP) staining. (2) Six newly born C(57) BL/6 mice were intraperitoneally injected with 50 µg/g BrdU (two times a day) for three days for ESCs-labelling. Seven weeks later, the mice were inflicted with superficial partial-thickness burn on the back. Serial slices of burn wound tissue were prepared at PBH 72 and immunohistochemically stained with SP for observation of the co-localization of BrdU-positive ESCs and P311-positive cells. (3) The empty vector pAdEasy-enhanced green fluorescence protein (EGFP) and the adenovirus P311-expressing vector named pAdEasy-EGFP-P311 were constructed and packed. Human ESCs were isolated by the method of rapid adhesion to collagen IV. After being divided into P311 high-expressing group (n = 3) and EGFP control group (n = 3), the ESCs in two groups were respectively infected by pAdEasy-EGFP-P311 and pAdEasy-EGFP. Scratching assay was performed on ESCs in both groups after they were treated by mitomycin C for 2 hours. The remaining area within the fixed range was measured at post scratching hour (PSH) 0, 24, 48, and 72, and the wound-area healing rate was calculated. Data were processed with independent samples t test.</p><p><b>RESULTS</b>(1) Expression amount of P311 was different in different parts of wound at different time points after burn. Expression amount of P311 in the newly formed epidermis and hair follicle of wound increased along with prolongation of time. Expression amount of P311 in the epidermis and hair follicle of wound edge peaked at PBH 12 and then decreased to normal levels at PBH 72. (2) Co-localization of BrdU-positive ESCs and P311-positive cells was observed in the new epidermal layer of wound tissue of mice, where ESCs were labeled by BrdU. (3) At PSH 48 and 72, wound-area healing rate was obviously higher in P311 high-expressing group [(69 ± 31)%, (89 ± 26)%] than in EGFP control group [(35 ± 12)%, (46 ± 31)%, with t values respectively -2.336, -2.611, P values all below 0.05].</p><p><b>CONCLUSIONS</b>P311 may promote the migration of ESCs both in rats with superficial partial-thickness burns and in injured cell model in vitro, and it may play an important role in wound healing.</p>

Present status and prospects of professional facilities for wound healing / 中华烧伤杂志

It is essential for the development of modern clinical medicine to establish a professional facility and team for wound healing. There is some successful experience of constructing and running the wound healing center to be mirrored at home and abroad. The construction of the facility and team for wound healing will be promoted by guideline issuing, profession certification, and others, which would push forward the clinical treatment and basic research of wound healing.

Effect of nitric oxide on HaCaT cell migration / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effect of exogenous nitric oxide (NO) on the migration of HaCaT cell and its possible mechanism.</p><p><b>METHODS</b>Sodium nitroprusside (SNP) was used as the donor of NO. Different concentrations of SNP (0.1, 1.0, 10.0, 100.0, 1000.0 micromol/L) were added into nutrient culture medium of HaCaT cells. Cell migration rate was observed and calculated at post scratching hour (PSH) 0 (immediately after scratching), 6, 12, 24, 48. The most suitable concentration of SNP and culture duration were selected as stimulation condition. Cytoskeletons of HaCaT cells were observed under confocal laser scanning microscope. The expressions of integrin beta 1, RhoA, Rac1 and Cdc42 of cells in experiment group (cultured with 10.0 micromol/L SNP for 24 hours) and negative control group were determined at mRNA and protein levels with RT-PCR and Western blot respectively. Data were processed with one-way analysis of variance (ANOVA) and repeated measure ANOVA.</p><p><b>RESULTS</b>Migration rate of HaCaT cells in each group increased gradually as time after scratching went on. There were significant differences between PSH 6-48 and PSH 0 in cells cultured with 10.0 micromol/L SNP (F = 31.002, P values all below 0.05). Pili were rarely observed in negative control group with slender stress fibers in cells. In comparison, the amount of pili amount increased obviously in experiment group with thickened stress fibers. Compared with those of cells in control group (RhoA protein expression = 0.64 +/- 0.04), integrin beta 1 expression decreased obviously (F = 8.25, P = 0.015), RhoA (0.92 +/- 0.04), Cdc42 and Rac1 were up-regulated at both protein (with F value respectively 7.25, 14.10, 6.50, P values all below 0.05) and mRNA levels (with F value respectively 23.67, 10.39, 9.52, P values all below 0.05).</p><p><b>CONCLUSIONS</b>Exogenous NO in suitable concentration can promote the proliferation and migration of HaCaT cell, suggesting it exerts significant effect in wound repair. The changed cytoskeletons and the down-regulated integrin beta 1 expression may be involved in this process.</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>

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>

Study of xenotransplantation of fetal pig skin precursor tissue / 中华烧伤杂志

<p><b>OBJECTIVE</b>To select the optimal pregnancy time window of embryonic pig skin precursor tissue for xenotransplantation and study its ability in wound repair.</p><p><b>METHODS</b>Skin precursor tissues were obtained from pig fetus of fetal age of 35, 42, 56, 70 days, and were minced into microskin and transplanted to dorsal wounds of BALB/c nude mice, then they were covered with residual skin after plastic surgery of patients or adult pig skin (white). The characteristics of growth and development were observed after transplantation. Pathological examination was performed on 6 and 12 post operation weeks respectively to observe the tissue structure and tumorigenicity.</p><p><b>RESULTS</b>Skin precursor tissues from fetal pig survived and developed after transplantation, and the microskin fused. New tissue area from skin precursor tissues with fetal age of 42 days was (47 +/- 6) mm2, which was higher than that of 35 days (18 +/- 8 mm2), 56 days (31 +/- 12 mm2), 70 days (20 +/- 8 mm2, P < 0.05). The skin precursor developed into "intact skin" with hair, sebaceous glands and sweat glands, and melanocytes were also detected in epidermis. The newly-grown skin tissue included epidermal and dermal layer, and obvious dermal papillae. Teratoma was not found after transplantation in skin precursor tissue with fetal age of 56, 70 days.</p><p><b>CONCLUSION</b>Fetal pig skin precursor tissue with fetal age of 56 days can be used to repair wound as xenotransplantation.</p>

Influence of signal transduction modulators on the secretory function of T lymphocytes in severely scalded mice and its mechanism / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of various signal transduction modulators on the splenic T lymphocytes secretion of IL-2 and IL-10 in severely scalded mice, and to explore its mechanism.</p><p><b>METHODS</b>The mice were inflicted with 18% TBSA full-thickness scald by high-pressure heat vapour, and T lymphocytes were isolated from murine splenocytes through nylon wool column at 12 and 96 post-scald hours (PSH). Then the cells were divided into following groups: i. e. control, scald, scald and modulator [1 ml of 50 micromol/L PKC inhibitor ( H-7) , 30 micromol/L tetradecanoylphorbol-13-acetate (TPA) , 10micromol/L nonreceptor tyrosine protein kinase inhibitor (herbimycin) , 25 microg/ml of mitogen activated protein kinase kinase inhibitor (PD098059) , 100 nmol/L Calcium ionophore ( A23187) were added to the cells, respectively] groups. The scald group was subdivided into S1 (with scald at 12 PSH) and S2 (with scald at 96 PSH) groups. The modulator group was subdivided into modulator, S1 and modulator( the modulators were added into cells at 12 PSH) , and S2 and modulator( the modulators were added to cells at 96 PSH) groups. The influence of modulators to T lymphocyte secretion of IL-2 and IL-10 were observed.</p><p><b>RESULTS</b>After the addition of H-7, the IL-2 and IL-10 levels in each group were obviously lower than that in controls( P <0. 05 or 0.01) , and that in S1 and H7 group, S2 and H7 group were obviously lower than that in scald group at corresponding time-points( P <0.01). The levels of IL-10, and especially IL-2 were elevated by TPA, but they were markedly lower than that in control group after PD098059 pretreatment. The secretion of IL-2 and IL-10 was significantly suppressed by herbimycin in S1 and herbimycin, and S2 and herbimycin groups, but those in Sl and A21387[ (2 417+/-39) pg/ml, (2 793+/-25)pg/ml] , S2 and A21387 [ (921+/-50) pg/ml, (2 633+/-35)pg/ml] groups were evidently higher than those in S1[ (1 542+/-40)pg/ml, (2 390+/-15)pg/ml] , S2 [(328+/-19)pg/ml, (1 618+/-21)pg/ml,( P <0.05 or <0.01)]groups.</p><p><b>CONCLUSION</b>PKC, calcium, MAPKK and TPK play critical roles in the dysfunction of splenic T lymphocyte secretion of IL-2 and IL-10 in severely scalded mice, among which TPK and PKC are mainly targeted to IL-2 secretion, and MAPKK is targeted to IL-10 secretion. TPA and A23187 can markedly rectify the disturbance of IL-2/IL-10 secretion ratio by increasing the IL-2 secretion after scald.</p>