Changes of heparin-binding protein in severe burn patients during shock stage and its effects on human umbilical vein endothelial cells and neutrophils / 中华烧伤杂志

Objective: To investigate the changes of heparin-binding protein (HBP) in severe burn patients during shock stage and its effects on human umbilical vein endothelial cells (HUVECs) and neutrophils in vitro. Methods: Prospective observational and experimental research methods were used. Twenty severe burn patients who met the inclusion criteria and were admitted to the Department of Burns and Plastic Surgery of Affiliated Suzhou Hospital of Nanjing Medical University from August to November 2020 were included in severe burn group (12 males and 8 females, aged 44.5 (31.0, 58.0) years). During the same period, 20 healthy volunteers with normal physical examination results in the unit's Physical Examination Center were recruited into healthy control group (13 males and 7 females, aged 39.5 (26.0, 53.0) years). Enzyme-linked immunosorbent assay (ELISA) method was used to detect the protein expression levels of HBP and tissue inhibitor of metalloproteinase 1 (TIMP-1) in plasma of patients within 48 hours after injury in severe burn group and in plasma of volunteers in healthy control group. The correlation between protein expression of HBP and that of TIMP-1 in the plasma in the two groups was analyzed by Pearson correlation analysis. The fourth passage of HUVECs in logarithmic growth phase were used for the experiment. The HUVECs were divided into normal control group with routine culture (the same treatment below) and recombinant HBP (rHBP)-treated 12 h group, rHBP-treated 24 h group, and rHBP-treated 48 h group with corresponding treatment according to the random number table (the same grouping method below), and the mRNA expression of TIMP-1 in cells was detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction. The HUVECs were divided into normal control group and rHBP-treated 48 h group with corresponding treatment, and the protein expression of TIMP-1 in the cells was detected by Western blotting. The HUVECs were divided into normal control group, rHBP alone group, aprotinin alone group, and rHBP+aprotinin group treated with the corresponding reagents (with the final molarity of rHBP being 200 nmol/L and the final concentration of aprotinin being 20 μg/mL, respectively), cultured for 48 h, and ELISA was used to detect the protein expression of TIMP-1 in the culture supernatant of cells. The neutrophils were isolated from the peripheral venous blood of the aforementioned 10 healthy volunteers by immunomagnetic bead sorting, and the cells were divided into normal control group, recombinant TIMP-1 (rTIMP-1) alone group, phorbol acetate (PMA) alone group, and rTIMP-1+PMA group treated with corresponding reagents (with the final concentration of rTIMP-1 being 500 ng/mL and the final molarity of PMA being 10 nmol/L, respectively). After being cultured for 1 h, the expression of CD63 protein in cells was detected by immunofluorescence method, the positive expression rate of CD63 protein in cells was detected by flow cytometry, and the protein expression levels of HBP and myeloperoxidase (MPO) in the culture supernatant of cells were detected by ELISA. The normal control group underwent the above-mentioned related tests at appropriate time points. The number of samples was 3 in each group of cell experiment. Data were statistically analyzed with chi-square test, Mann-Whitney U test, Kruskal-Wallis H test, and Tamhane's T2 test. Results: The protein expression levels of HBP and TIMP-1 in the plasma of patients in severe burn group were 404.9 (283.1, 653.2) and 262.1 (240.6, 317.4) ng/mL, respectively, which were both significantly higher than 61.6 (45.0, 68.9) and 81.0 (66.3, 90.0) ng/mL of volunteers in healthy control group (with Z values of -5.41 and -5.21, respectively, P<0.01). The correlation between the protein expression of HBP and that of TIMP-1 in the plasma of volunteers in healthy control group was not strong (P>0.05). The protein expression of HBP was significantly positively correlated with that of TIMP-1 in the plasma of patients in severe burn group (r=0.64, P<0.01). Compared with that in normal control group, the mRNA expression of TIMP-1 in HUVECs was significantly increased in rHBP-treated 12 h group, rHBP-treated 24 h group, and rHBP-treated 48 h group (with t values of -3.58, -2.25, and -1.26, respectively, P<0.05). Western blotting detection showed that compared with that in normal control group, the protein expression of TIMP-1 in HUVECs in rHBP-treated 48 h group was significantly enhanced. After 48 h of culture, compared with that in normal control group, the protein expression level of TIMP-1 in the culture supernatant of HUVECs in rHBP alone group was significantly increased (t=9.43, P<0.05), while the protein expression level of TIMP-1 in the culture supernatant of HUVECs didn't change significantly in aprotinin alone group or rHBP+aprotinin group (P>0.05); compared with that in rHBP alone group, the protein expression level of TIMP-1 in the culture supernatant of HUVECs in rHBP+aprotinin group was significantly decreased (t=4.76, P<0.01). After 1 h of culture, the trend of CD63 protein expression in neutrophils detected by immunofluorescence method and that by flow cytometry were consistent in each group. After 1 h of culture, compared with that in normal control group, the positive expression rate of CD63 protein in the neutrophils and the protein expression levels of HBP and MPO in the culture supernatant of cells in rTIMP-1 alone group all had no significant changes (P>0.05), while the positive expression rate of CD63 protein in the neutrophils and the protein expression levels of HBP and MPO in the culture supernatant of cells were all significantly increased in PMA alone group and rTIMP-1+PMA group (with t values of 2.41, 3.82, 5.73, 1.05, 4.16, and 1.08, respectively, P<0.05 or P<0.01); compared with that in PMA alone group, the positive expression rate of CD63 protein in the neutrophils and the protein expression levels of HBP and MPO in the culture supernatant of cells in rTIMP-1+PMA group were all significantly decreased (with t values of 5.26, 2.83, and 1.26, respectively, P<0.05 or P<0.01). Conclusions: The expression level of HBP in the plasma of severe burn patients is increased during shock stage. HBP can induce HUVECs to secrete TIMP-1 in vitro, and TIMP-1 can reduce the expression of CD63 molecule in human neutrophils.

Re-understanding the physiological and pathophysiological roles of neutrophils / 中华烧伤杂志

Neutrophils have always been considered as a short-lived and homogeneous cell type in the innate immune system, which have limited pro-inflammatory or anti-inflammatory effects. However, in recent 10 years, the understanding of neutrophils has been undergoing some kind of revival as researches progressed. The researches on the heterogeneity of neutrophils and the mechanism of their interaction with other immune cells have promoted the researchers to re-understand the physiological and pathophysiological roles of neutrophils. In the following decades, with the development of single-cell sequencing technology, spatial transcriptome sequencing technology, and multi-omics combined sequencing technology, researchers will have a better understanding of the biological behaviors of neutrophils. This paper briefly reviews the biological behaviors of neutrophils and their roles in various diseases in recent years.

Biological behavior of neutrophils in sepsis / 医学研究生学报

Neutrophils are a type of important native immune cells that play a very important role in nonspecific cellular immunity. As the first defensive army against microbial pathogens, especially pyogenic bacteria, neutrophils perform the functions of chemotaxis and phagocytosis, but meanwhile they may induce different degrees of inflammatory response and cause local or systemic immuno-pathologic impair. At present, the changes in the pathophysiological and biological behaviors of neutrophils in sepsis need to be studied more comprehensively, and effective regulation and utilization of neutrophils are required in the treatment of sepsis. This review summarizes some important pathophysiological changes in neutrophils in sepsis, including apoptosis, autophagy and pyroptosis, focusing on the biological behavior of neutrophils in the development and progression of sepsis.

Effects of exogenous carbon monoxide-releasing molecules 2 on the vitality and toxicity of E.coli / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the effects of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on the vitality and toxicity of E. coli ATCC 25922, and to analyze the potential mechanism.</p><p><b>METHODS</b>(1) In vitro experiments. Standard strains of E. coli ATCC 25922 were divided into groups A (without addition), B, C, D, and E according to the random number table, and then the latter 4 groups were respectively cultured with 1.2 mmol/L CORM-2, 1.6 mmol/L CORM-2, 1.2 mmol/L inactive CORM-2 (iCORM-2), 1.6 mmol/L iCORM-2, with six samples in each group. After being cultured for 0, 3, 5, 8, 10, 12, 16, 20, 24, 27, 30, 48 hours, proliferative vitality of E. coli was examined (denoted as absorption value under 600 nm wavelength), and bacteria number was counted. Other standard strains of E. coli ATCC 25922 were divided into groups F (without addition) and G (cultured with 0.8 mmol/L CORM-2), the expressions of genes fliA, dnaK, marA, and waaQ related to E. coli were detected by quantitative real-time (qRT)-PCR. (2) In vivo experiments. Other standard strains of E. coli ATCC 25922 were grouped as A', B', C', D', and E' and treated with the same method as that in groups A, B, C, D, and E, and 0.5 mL bacterial liquid of each group were collected when the absorption value of bacterial liquid in group A' was equal to 0.4 (under 600 nm wavelength). Seventy-two C57BL/6 mice were divided into groups, namely blank control (without treatment), H, I, J, K, and L according to the random number table, with 12 mice in each group. The mice in the latter 5 groups were intraperitoneally injected with 0.5 mL bacterial suspension of groups A', B', C', D', and E' respectively. After injection, general condition of mice in groups H, I, J, K, and L was observed. The serum levels of TNF-α and IL-6 were determined at post injection hour (PIH) 6, 12. The liver and lung samples were harvested for determination of myeloperoxidase (MPO) activity at PIH 12. The same process was carried out in blank control group. Data were processed with repeated measure analysis of variance (ANOVA), factorial design ANOVA, one-way ANOVA, and t test.</p><p><b>RESULTS</b>(1) In vitro experiments. Compared with those of groups A and D, the proliferative vitality and bacteria number of E. coli in group B were all decreased (with F values respectively 1170.80, 217.52, P values all below 0.01). Compared with those of groups A and E, the proliferative vitality and bacteria number of E. coli in group C were also obviously decreased (with F values respectively 7948.34, 14 432.85, P values all below 0.01). Compared with those in group F, the expression of fliA was downregulated, while the expressions of dnaK, marA, and waaQ were upregulated in group G (with t values 30.28, -165.54, -168.88, -187.28, P values all below 0.01). (2) In vivo experiments. Symptoms including listlessness and tachypnea were observed in mice in groups H, K, and L, and they were ameliorated or not obvious in groups I and J. At PIH 6, the serum levels of TNF-α and IL-6 in groups H and K were respectively (647.3 ± 3.8) pg/mL, (3.44 ± 0.22) ng/mL and (639.3 ± 0.8) pg/mL, (2.47 ± 0.32) ng/mL, which were obviously higher than those in group I [(124.6 ± 10.7) pg/mL, (1.03 ± 0.16) ng/mL, with t values from 15.22 to 84.03, P values all below 0.01]. The serum levels of TNF-α and IL-6 in group J at PIH 6, 12 were also obviously decreased as compared with those in groups H and L (with t values from 19.27 to 245.34, P values all below 0.01). MPO activity of liver and lung tissues were significantly attenuated in group I at PIH 12 as compared with those in groups H and K, and it was also attenuated in group J when compared with those in groups H and L (with t values respectively from 17.36 to 18.92 and 2.35 to 3.61, P values all below 0.01).</p><p><b>CONCLUSIONS</b>CORM-2 can obviously inhibit the vitality and toxicity of E. coli, which might be attributable to regulation of expressions of genes fliA, dnaK, marA, and waaQ of E. coli.</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>

Inhibitory effect of extrinsic CO-releasing molecules-2 (CORM-2) on inflammatory responses in mice with LPS-induced acute lung injury / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of extrinsic CO-releasing molecules-2 (CORM-2) on attenuating pulmonary injury and the inflammatory response in LPS-induced acute lung injury of mice.</p><p><b>METHODS</b>Fifty-three mice were assigned to four groups. Mice in sham group (n= 8) underwent sham inhalation, whereas mice in ALI (n= 15) received inhalation of LPS for 30 min, mice in ALI+iCORM (n= 15) underwent LPS inhalation with immediate administration of inactive CORM-2 (8 mg/kg, i.v.), mice in ALI+CORM (n= 15) underwent LPS inhalation with immediate administration of CORM-2 (8 mg/kg, i.v.). PMN accumulation (MPO assay) in mice lungs and TNF-α and IL-1 β in BAL fluid were determined. Activation of NF-kB and expression level of ICAM-1 in the lung were assessed.</p><p><b>RESULT</b>Treatment of ALI mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-kB in the lung. This was accompanied by a decrease of the expression of ICAM-1. In parallel, CORM-2 markedly decreased the production of inflammatory mediators in BAL fluid.</p><p><b>CONCLUSION</b>CORM-2 attenuates the inflammatory response in the lung of LPS-induced ALI by decreasing leukocyte sequestration and interfering with NF-kB activation, expression of ICAM-1 and therefore suppressing endothelial cells pro-adhesive phenotype.</p>

Inhibitive effect of exogenous carbon monoxide-releasing molecules 2 on the activation of Janus kinase/signal transducer and activator of transcription pathway in sepsis / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the inhibitive effect of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on the activation of Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in sepsis.</p><p><b>METHODS</b>RAW264.7 cells were divided into normal control group, LPS group (10 mg/mL LPS, the same concentration below), LPS + inactive CORM-2 (iCORM-2) group, LPS + 50 mmol/L CORM-2 group, and LPS + 100 mmol/L CORM-2 group. TNF-alpha level in the supernatant was determined with ELISA, and the phosphorylation levels of JAK1 and JAK3 were determined with Western blot. Thirty-five male BALB/c mice were divided into normal control group, cecal ligation and puncture (CLP) group, CLP + iCORM-2 (8.0 mg/kg) group and CLP + CORM-2 group (8.0 mg/kg) according to the random number table. Mice in CLP + CORM-2 group were treated the same as mice in CLP group except for administration of CORM-2 after CLP. The plasma levels of TNF-alpha, IL-1beta, and the phosphorylation levels of JAK1, JAK3 in liver tissue were determined with ELISA 24 hours post CLP. Data were processed with t test.</p><p><b>RESULTS</b>Compared with that of normal control group [(1.9 +/- 0.3) pg/mL], the TNF-alpha level [(8.2 +/- 2.7) pg/mL, t = 2.844, P < 0.01] and phosphorylation levels of JAK1, JAK3 in LPS group increased significantly; while TNF-alpha levels in LPS + 50 mmol/L CORM-2 and LPS + 100 mmol/L CORM-2 groups decreased obviously as compared with that of LPS group [(5.7 +/- 1.4), (3.2 +/- 0.9) pg/mL, with t value respectively 2.104 and 2.363, P values all below 0.05], and it was the same with phosphorylation levels of JAK1, JAK3 in a dose-dependent manner. Compared with those of normal control group, plasma levels of TNF-alpha and IL-1beta and phosphorylation levels of JAK1, JAK3 in liver tissue significantly increased in CLP group (with t value respectively 2.916 and 2.796, and P values all below 0.05); while plasma levels of TNF-alpha and IL-1beta and the phosphorylation levels of JAK1, JAK3 in liver tissue decreased significantly in CLP + CORM-2 group (with t value respectively 2.115 and 2.398, and P values all below 0.05).</p><p><b>CONCLUSIONS</b>Exogenous CORM-2 can obviously inhibit the phosphorylation of JAKs molecules and then inhibit the activation of JAK/STAT signal pathway in sepsis, and decrease the expression of downstream cytokines to effectively prevent cascade reaction in the inflammatory response after severe infection.</p>

Inhibitive effect of exogenous carbon monoxide-releasing molecules 2 on tissue factor expression in sepsis / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the inhibitive effects of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on expression of tissue factor (TF) in sepsis.</p><p><b>METHODS</b>Human umbilical vein endothelial cells (HUVEC) were cultured with trypsin digestion method, which were divided into NC group (with normal treatment), LPS group (with culture of 10 microg/mL LPS), LD group (with 10 microg/mL LPS and DMSO in co-culture), LC1 group (with 10 microg/mL LPS and 10 micromol/L CORM-2 in co-culture), LC2 group (with 10 microg/mL LPS and 50 micromol/L CORM-2 in co-culture), LC3 group (with 10 microg/mL LPS and 100 micromol/L CORM-2 in co-culture). After culture for 4 hours, TF activity, TF protein expression, nuclear factor-kappaB (NF-kappaB) activity were examined. Forty-five C57 BL/6 male mice were randomly divided into NC (without treatment, n = 5), CLP (n = 5) and CLP + CORM-2 (with treatment of 8 mg/kg CROM-2 after CLP, n = 5) groups. The serum samples in CLP, CLP + CORM-2 groups were collected at 2, 6, 12 and 24 post operation hour ( POH, 5 mice at each time point) for determination of TF and TFPI levels,which were also examined in NC group.</p><p><b>RESULTS</b>Compared with those of NC group, TF activity increased (P < 0.01) , TF protein expression and NF-KB activity also increased in LPS group. Compared with those of LPS group, above indices were decreased in LC1, LC2, LC3 groups. The serum level of TF in CLP group at 6 POH was higher than that of NC group (80.0 +/- 11.9 pg/mL vs 58.4 +/- 6.9 pg/mL, P < 0.05), peaked at 12 POH, and still higher than that of NC group at 24 POH, while the serum level of TFPI showed no obvious difference in NC and CLP groups. Compared with that of NC group, TFPI levels obviously increased in CLP + CORM-2 group at 6, 12 POH (23.7 +/-3.5 ng/mL, 24.4 +/- 5.0 ng/mL vs 12.4 +/- 2.8 ng/mL, P < 0.05).</p><p><b>CONCLUSIONS</b>Exogenous CORM can obviously inhibit TF and NF-KB activity,decrease TF protein expression. Meanwhile, it can also decrease serum level of TF, and increase serum level of TFPI, preventing activation of procoagulant system, balancing procoagulant and anticoagulant system in sepsis.</p>

The inhibitory effects of extrinsic carbon monoxide-releasing molecules II on inflammatory responses in liver of mice with severe burns / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the inhibitory effects of extrinsic carbon monoxide-releasing molecules II on inflammatory responses in liver of mice with severe burns and its potential mechanisms.</p><p><b>METHODS</b>Forty-five male C57BL/6 mice were randomly divided into sham (simulation of burn with 37 degrees C warm water), sham + CORM-2 (with 8 mg/kg CORM-2 after the same manipulation as sham group), burn (with 15% TBSA full-thickness burns), burn + CORM-2 (with 8 mg/kg CORM-2 after the same manipulation as burn group), burn + DMSO (with DMSO after the same treatment as burn group) groups,with 9 mice in each group. The serum level of ALT and AST were determined at 24 post-burn hours (PBH), and the level of myeloperoxidase (MPO), nuclear factor (NF) kappaB, intercellular adhesion molecular (ICAM-1), vascular cell adhesion molecular (VCAM-1), as well as adhesion of polymorphonuclear leucocytes to sinusoidal endothelial cells (HSECs) after serum stimulation were detected and assessed at the same time-points.</p><p><b>RESULTS</b>The level of ALT and AST (398 +/- 34,122 +/- 22 ), the activity of MPO and NF-kappaB, the protein level of ICAM-1 and VCAM-1 in burn group were obviously increased when compared with those in sham group and burn + CORM-2 group (P < 0.05 or P < 0.01). Additionally, the adhesion of PMN on HSEC after stimulation of serum in burn group was enhanced, while it was markedly inhibited after stimulation of serum in burn + CORM-2 group (P < 0.05).</p><p><b>CONCLUSION</b>Extrinsic CORM-2 exhibits the ability to inhibit NF-kappaB activity, reduces the hepatic expression of ICAM-1 and VCAM-1, thereby alleviating sequestration of leukocytes after severe burns, so that hepatic inflammatory response is ameliorated, and liver function is improved.</p>

The effects of dexamethasone and hyperbaric oxygen on the survival of subdermal vascular networks / 中华物理医学与康复杂志

Objective To study the effects of dexamethasone (DEX) and/or hyperbaric oxygen (HBO) on the subdermal vascular network (SVN).Methods SVNs were selected on dorsal skin flaps of 40 Wistar rats.The animals were divided randomly into a control group,a DEX group,a HBO group and a HBO+DEX group.Cranially based,2.5 cm?10 cm dorsal SVN skin flaps were sharply incised and elevated between the dartos and SVN,then sutured to their beds.On the 7th postoperative day,the surviving flap area was measured along with the number of new capillary,the thickness of meat tissue and the number of infiltrated neutrophilie granulocytes in the SVN skin flap.Results The mean surviving flap area for the control group was 7.90 cm~2,for the DEX group it was 10.48 cm~2,for the HBO group 15.53 cm~2,and for the DEX+HBO group it was 15.58 cm~2.The improvement in surviving flap area was highly statistically signifieant compared with the control.The improvement was also statistical- ly significant when the HBO group or HBO+DEX group was compared with the DEX group.However,no statistically significant difference was found between the HBO group and HBO+DEX group.Conclusion In a rat dorsal skin flap model,DEX or HBO improved skin flap viability,but DEX alone is not as efficacious as HBO or as DEX+ HBO.DEX plus HBO showed no additive beneficial effect over HBO alone.