[Regulatory effects of the Nocardia rubra cell wall skeleton on the biological function of human neutrophils]

Objective: To investigate the regulatory effects and mechanism of Nocardia rubra cell wall skeleton (Nr-CWS) on the biological function of human neutrophils. Methods: The experimental research method was used. Fifteen healthy adult volunteers (7 males and 8 females, aged 24 to 45 years) were recruited from Suzhou Physical Examination Center for physical examination from May to October 2022, the peripheral venous blood was collected, and neutrophils were extracted by immunomagnetic bead sorting. The cells were divided into normal control group without any treatment, Nr-CWS alone group treated with Nr-CWS of final mass concentration 60 ng/mL alone, endotoxin/lipopolysaccharide (LPS) alone group stimulated with LPS of final mass concentration 1 μg/mL alone, and LPS+Nr-CWS group stimulated with LPS first and then treated with Nr-CWS as before. After 1 h of culture, the chemotaxis distance, chemotactic cell percentage, chemotactic index, maximum chemotactic speed, and chemotactic function score of neutrophils were detected using the modified agarose chemotactic model; the proportion and fluorescence intensity of phagocytosis cells, the level of reactive oxygen species (ROS), the protein expression levels of granular protein CD35, CD66b, and CD63, and the concentrations of inflammatory cytokines of interleukin 2 (IL-2), IL-4, IL-6, IL-10, IL-17A, tumor necrosis factor alpha (TNF-α), and interferon-γ in cell culture supernatant were detected by flow cytometry. The number of samples in each group in the above experiments was 15. Data were statistically analyzed with analysis of variance for factorial design and independent sample t test. Results: After 1 h of culture, the chemotactic function score of cells in normal control group, Nr-CWS alone group, LPS alone group, and LPS+Nr-CWS group were 15.0, 14.5±0.5, 1.5±0.5, 12.0±1.5, respectively. Compared with those in normal control group, the chemotaxis distance, chemotactic cell percentage, chemotactic index, maximum chemotactic speed, and chemotactic function score of cells were significantly decreased in LPS alone group and LPS+Nr-CWS group (with t values of 18.36, 18.88, 54.28, 18.36, 46.77, 10.58, 14.74, 6.84, 10.58, and 4.24, respectively, P<0.05); compared with those in LPS alone group, the five chemotactic function indexes as above in LPS+Nr-CWS group were significantly increased (with t values of 11.47, 14.65, 11.62, 11.47, and 13.75, respectively, P<0.05). After 1 h of culture, compared with those in normal control group, the proportion and fluorescence intensity of phagocytosis cells were significantly increased in Nr-CWS alone group (with t values of 6.86 and 6.73, respectively, P<0.05), and the above two indexes were significantly decreased in LPS alone group (with t values of 7.35 and 22.72, respectively, P<0.05) and LPS+Nr-CWS group (with t values of 21.37 and 13.10, respectively, P<0.05). After 1 h of culture, compared with that in normal control group, the level of ROS of cells in LPS alone group was significantly increased (t=6.64, P<0.05); compared with that in LPS alone group, the level of ROS of cells in LPS+Nr-CWS group was significantly decreased (t=5.46, P<0.05). After 1 h of culture, compared with those in normal control group, the protein expressions of CD35, CD66b, and CD63 of cells were significantly increased in LPS alone group and LPS+Nr-CWS group (with t values of 16.75, 17.45, 10.82, 5.70, 19.35, and 15.37, respectively, P<0.05); compared with those in LPS alone group, the protein expressions of CD35, CD66b, and CD63 of cells were significantly decreased in LPS+Nr-CWS group (with t values of 4.92, 5.72, and 3.18, respectively, P<0.05). After 1 h of culture, compared with those in normal control group, the concentrations of IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly increased in LPS alone group (with t values of 22.10, 9.50, 7.21, 10.22, 24.88, 8.43, and 47.48, respectively, P<0.05), and the concentrations of IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly increased in LPS+Nr-CWS group (with t values of 4.68, 5.12, 8.02, 5.58, and 7.13, respectively, P<0.05); compared with those in LPS alone group, the concentrations of IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly decreased in LPS+Nr-CWS group (with t values of 5.39, 2.83, 5.79, 2.90, 5.87, 4.88, and 39.64, respectively, P<0.05). Conclusions: Nr-CWS can enhance the phagocytosis ability of neutrophils in normal condition and improve the chemotactic function, ROS level, degranulation protein level, and inflammatory factor level of human neutrophils in infectious condition. Nr-CWS can enhance the anti-infection ability of human neutrophils by regulating its biological behavior in innate immunity.

Expert consensus on the monitoring and treatment of sepsis-induced immunosuppression

Emerged evidence has indicated that immunosuppression is involved in the occurrence and development of sepsis. To provide clinical practice recommendations on the immune function in sepsis, an expert consensus focusing on the monitoring and treatment of sepsis-induced immunosuppression was developed. Literature related to the immune monitoring and treatment of sepsis were retrieved from PubMed, Web of Science, and Chinese National Knowledge Infrastructure to design items and expert opinions were collected through an online questionnaire. Then, the Delphi method was used to form consensus opinions, and RAND appropriateness method was developed to provide consistency evaluation and recommendation levels for consensus opinions. This consensus achieved satisfactory results through two rounds of questionnaire survey, with 2 statements rated as perfect consistency, 13 as very good consistency, and 9 as good consistency. After summarizing the results, a total of 14 strong recommended opinions, 8 weak recommended opinions and 2 non-recommended opinions were produced. Finally, a face-to-face discussion of the consensus opinions was performed through an online meeting, and all judges unanimously agreed on the content of this consensus. In summary, this expert consensus provides a preliminary guidance for the monitoring and treatment of immunosuppression in patients with sepsis.

[Efficacy and prognostic factors of endoscopic optic canal decompression in children with traumatic optic neuropathy]

Objective: To explore the efficacy and prognostic factors of endoscopic optic canal decompression in children with traumatic optic neuropathy (TON). Methods: The clinical data of 47 children with TON treated with endoscopic optic nerve decompression in the Department of Neurosurgery of Beijing Tongren Hospital from November 2010 to October 2021 were retrospectively analyzed, and the visual acuity before and after treatment was compared. The clinical factors were taken as independent variables, and visual improvement was taken as dependent variable for multivariate Cox regression analysis to observe the factors that may affect the efficacy. Results: There were 47 patients in this study, including 35 males and 12 females, and the age ranged from 3.0 to 12.0 (7.2±2.3) years. After surgery and hormone treatment, 28 (59.6%) cases obtained visual improvement. Univariate analysis showed that the improvement rate of visual acuity in patients with residual vision after injury was higher than that in patients without vision [85.0% (17/20) vs 40.7% (11/27), P=0.002], while the improvement rate of visual acuity in patients with dislocated optic canal fracture was lower than that in those without fracture [42.1% (8/19) vs 71.4% (20/28), P=0.044]. The improvement rate of visual acuity in patients with operation time interval ≤7 d was higher than that in patients with operation time interval>7 d [80.8% (21/26) vs 33.3% (7/21), P=0.001]. Multivariate Cox regression analysis showed that post-traumatic residual visual acuity (HR=3.805, 95%CI: 1.087-13.318, P=0.037) and operation time interval≤7 d (HR=2.883, 95%CI: 1.084-7.662, P=0.034) were protective factors for post-surgical visual acuity. Conclusions: Endoscopic optic nerve decompression can effectively improve the visual acuity of children with TON. Post-traumatic residual visual acuity and operation time interval ≤7 d are independent protective factors for post-surgical visual acuity.

Recent advances in neutrophil chemotaxis abnormalities during sepsis

Sepsis remains one of the leading causes of death globally, in spite of advanced developments in intensive care and better understandings of pathophysiology related to sepsis. There is no special treatment or drug available for sepsis, currently. Under normal circumstances, neutrophil is a major player in acute infection control. However, during sepsis, the migration abilities and antimicrobial functions of neutrophils are impaired, resulting in a dysregulated immune response. Recent studies have indeed demonstrated that blocking or reversing neutrophil migration and impaired antibacterial function can improve the outcomes in septic animal models. This article systemically synthesized information regarding related factors and signaling involved in the functions of neutrophils in sepsis. This review also discussed the possibility that neutrophils be used as a marker for specific diagnosis and/or prediction of the outcomes of sepsis.

[Re-understanding the physiological and pathophysiological roles of neutrophils]

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.

[Changes of heparin-binding protein in severe burn patients during shock stage and its effects on human umbilical vein endothelial cells and neutrophils]

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.

[Prospective study on the analysis of intestinal microflora changes and prediction on metabolic function in severe burn patients at early stage by 16S ribosomal RNA high-throughput sequencing]

Objective: To analyze the changes of intestinal microflora and to predict the metabolic function of intestinal microflora in severe burn patients at early stage by 16S ribosomal RNA (rRNA) high-throughput sequencing. Methods: In this prospective observational study, 48 patients with severe burns who met the inclusion criteria were admitted to Department of Burns and Plastic Surgery of Affiliated Hospital of Jiangsu University from January 2018 to December 2019 were included in burn group, and 40 healthy volunteers who met the inclusion criteria and underwent physical examination at the Physical Examination Center of Affiliated Hospital of Jiangsu University in the same period were included in healthy group. Fecal samples were collected from patients in burn group in about 1 week after admission and from volunteers in healthy group on the day of physical examination. The 16S rRNA V4 gene sequencing was performed in the feces of patients in burn group and volunteers in healthy group to analyze the relative abundance of various bacteria. The operational classification unit (OTU) was divided by Mothur software to analyze the dominant bacteria. The OTU number, Chao1 index, Ace index, and Shannon index of fecal microflora were analyzed by QIIME1.9.0 software. The principal component analysis for relative abundance of fecal microflora was performed by Canoco Software 5.0. The metabolic function of fecal microflora was predicted by Kyoto Encyclopedia of Genes and Genomes. Data were statistically analyzed with independent sample t test, and Mann-Whitney U test, and Bonferroni correction. Results: The relative abundance of Bacteroides, Enterococcus, Acinetobacter, Macrococcus, and Staphylococcus in feces of patients in burn group was significantly higher than that of volunteers in healthy group (Z=-5.20, -2.37, -5.17, -4.41, -6.03, P<0.05 or P<0.01), and the relative abundance of unclassified-Helicobacillae, Prevotella, Cecobacteria, unclassified-Rumencocci, Pseudobutyrivibrio, Brautia, and unclassified-Digiestive Streptococcaceae (Z=-8.03, -3.21, -7.63, -5.88, -8.05, -8.05, -6.77, P<0.01) and other 12 species of bacteria in the feces of volunteers in healthy group was significantly higher than that of patients in burn group. The diversity of fecal microflora of volunteers in healthy group was better than that of patients in burn group, the main dominant microflora of volunteers in healthy group were Bacteroides, unclassified-Helicobacillae, Prevotella, unclassified- Enterobacteriaceae, Brautia, Parabacteroides, Escherichia coli, etc., and the main dominant microflora of patients in burn group were Bacteroides, Prevotella, unclassified-Enterobacteriaceae, and Parabacteroides. The OTU number, Ace index, Chao1 index, and Shannon index of fecal microflora of patients in burn group were 149±47, 199±45, 190±45, 2.0±0.9, which were significantly lower than 266±57, 323±51, 318±51, 3.8±0.5 of volunteers in healthy group (t=10.325, 11.972, 12.224, 11.662, P<0.01). The relative abundance of fecal microflora of patients in burn group and volunteers in healthy group was clearly divided into two groups by principal component 1, and the contribution rate of principal component 1 was 32.50%, P<0.01. The fecal microflora of volunteers in healthy group were more concentrated on principal component 2, the fecal microflora of patients in burn group were dispersed in principal component 2, and the contribution rate of principal component 2 was 13.44%, P>0.05. The metabolic levels of alanine-aspartate-glutamate, arginine- proline, cysteine-methionine, glycine-serine-threonine, phenylalanine, tryptophan, and tyrosine in amino acid, tricarboxylic acid cycle, glucose and mannose, galactolipin, glycolysis/gluconiogenesis, starch and sucrose in carbohydrate of fecal microflora of patients in burn group were significantly lower than those of volunteers in healthy group (Z=-4.75, -4.54, -4.75, -4.62, -3.71, -3.28, -4.19, -3.82, -4.72, -4.35, -4.75, -4.71, P<0.01). The levels of lipoic acid metabolism and coenzyme Q synthesis of fecal microflora of patients in burn group were significantly higher than those of volunteers in healthy group (Z=-6.07, -4.51, P<0.01). The metabolic level of arachidonic acid of fecal microflora of patients in burn group was similar to that of volunteers in healthy group (P>0.05). Conclusions: There are significant differences in intestinal microflora between severe burn patients at the early stage and healthy people, and the species and diversity of microflora are decreased, and the nutrient metabolism level is decreased in burn patients by 16S rRNA high-throughput sequencing.

A narrative review of research progress on the relationship between hypoxia-inducible factor-2α and wound angiogenesis

OBJECTIVE

This article aims to pay attention to the latest research on the expression, activation and function of hypoxia-inducible factor-2α (HIF-2α) under hypoxia and non-hypoxia conditions, and summarizes the current knowledge about the interaction between hypoxia-inducible factor-2 and angiogenesis, hoping to understand its actions in physiology and disease, with the goal of providing a new strategy for the diagnosis and treatment of wounds.

BACKGROUND

Wound healing is a complex and continuous process, involving coagulation, inflammation, angiogenesis, new tissue formation and extracellular matrix remodeling. Of these, angiogenesis is an essential step. One of the main reasons for non-healing or delayed healing of wounds in peripheral vascular diseases and diabetes is the reduced ability to regenerate microvessels through the process of angiogenesis, which has become the focus of new methods for treating chronic wounds. HIF-2α regulates many aspects of angiogenesis, including vascular maturation, cell migration, proliferation and metastasis.

METHODS

Throughout extensive search of PubMed, summarize the medical research on HIF-2α to 2020.

CONCLUSIONS

HIF-2α is necessary for normal embryonic development by stimulating the expression of angiogenic factors, such as vascular endothelial growth factor (VEGF). It is essential for the formation of new blood vessels in physiological and pathophysiological environments. Targeting HIF-2α in wound healing has much clinical significance for tissue repair.

[Early changes of chemotactic function of peripheral blood neutrophil of patients with severe burns and the influence factor]

Objective: To observe the early changes of chemotactic function of peripheral blood neutrophil of patients with severe burns and the influence factor. Methods: Seven severe burn patients who met the inclusion criteria and were admitted to Suzhou Hospital Affiliated to Nanjing Medical University in 6 hours post burns from January to May 2019 were selected and included in burn group (4 males and 3 females, aged (36±10) years). Seven healthy volunteers with normal physical examination results in the Physical Examination Center of the same hospital in the same period of time were included in healthy control group (5 males and 2 females, aged (35±8) years). A prospective and controlled study was performed. (1) The venous blood of 2 mL was taken from each patient in burn group on post admission day (PAD) 1, 3, 5 and venous blood of 2 mL was taken from each volunteer in healthy control group for routine detection of white blood cell count, platelet count, neutrophil count, serum procalcitonin level, and C-reactive protein level. (2) The venous blood of patients and healthy volunteers was taken as before for measuring interleukin-6 (IL-6), IL-10, and tumor necrosis factor α (TNF-α) by enzyme-linked immunosorbent assay. (3) The venous blood of patients and healthy volunteers was taken as before, and peripheral blood neutrophils were isolated by Ficoll density gradient centrifugation. The chemotactic distance of neutrophil was detected by agarose chemotaxis test, and the positive expression rates of chemokine receptor CXCR1 and CXCR2 of patients in burn group on PAD 3 and volunteers in healthy control group were detected by flow cytometer. Data were statistically analysed with analysis of variance for repeated measurement, t test, and Bonferroni correction. Results: (1) The platelet count of patients in burn group on PAD 1, 3, 5 was close to that of volunteers in healthy control group respectively (t=0.55, 0.44, 0.12, P>0.05). The counts of neutrophil and white blood cell and the expression levels of serum procalcitonin and C-reactive protein of patients in burn group on PAD 1, 3, 5 were significantly higher than those of volunteers in healthy control group (t=196.96, 273.31, 45.22, 3.46, 4.18, 5.55, 4.36, 5.26, 11.13, 64.94, 89.97, 84.31, P<0.01). (2) The level of IL-6 of patients in burn group on PAD 1, 3, 5 was significantly higher than that of volunteers in healthy control group respectively (t=187.43, 213.54, 195.74, P<0.01), the level of IL-10 of patients in burn group on PAD 1, 3, 5 was significantly higher than that of volunteers in healthy control group respectively (t=21.47, 11.13, 6.23, P<0.01), and the level of TNF-α of patients in burn group on PAD 1, 3, 5 was significantly higher than that of volunteers in healthy control group respectively (t=5.27, 7.89, 15.58, P<0.01). (3) The chemotactic distances of neutrophil of patients in burn group were (1 479±102), (1 395±82), and (1 017±91) μm respectively on PAD 1, 3, 5, which were significantly shorter than (1 902±120) μm of volunteers in healthy control group (t=7.11, 9.23, 15.55, P<0.01). (4) The CXCR1 and CXCR2 positive expression rates of neutrophil of patients in burn group on PAD 3 were (48.3±1.6)% and (79.0±1.8)%, respectively, which were significantly lower than (95.4±4.5)% and (97.8±2.1)% of volunteers in healthy control group (t=27.13, 23.10, P<0.01). Conclusions: The chemotactic dysfunction of peripheral blood neutrophil was detected in the early stage of severe burn patients, which may be related to the decreases of CXCR1 and CXCR2.

[Summary of the 15th Syposium on Chinese Burn Medicine and the 2nd Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare]

The 15th Syposium on Chinese Burn Medicine and the 2nd Congress of Burn Medicine Branch of China International Exchange and Promotion Association for Medical and Healthcare (CPAM) was successfully held in Suzhou, from June 20th to 22th in 2019. A total of 400 specialists and scholars across the country attended the meeting. Focusing on the theme of " Guide and consensus: exploration and consideration " , with form of one main meeting place and two branch meeting places, the related hot and difficult problems were discussed warmly. During the conference, Working Conference of Editorial Committee of Chinese Journal of Burns, Standing Committee of the Chinese Burn Association, and the Congress of Burn Medicine Branch of CPAM were held.

[The diagnosis and treatment of traumatic optic nerve neuropathy combined with carotid artery injury]

Objective: To discuss the diagnosis and treatment strategy of traumatic optic nerve neuropathy (TON) combined with carotid artery injury. Methods: Retrospective analyses were performed 397 cases of TON at Neurosurgery department of Beijing Tongren Hospital, Capital Medical University (CMU), from January 2016 to December 2017.The clinical experience was concluded. Results: 9 cases of Traumatic Pseudo Aneurysm (TPA) and 16 cases of Traumatic Carotid Artery-Cavernous Sinus Fistula (TCCF) were found.7 cases of TPA were treated by covered stent, the other 2 cases were treated by detachable balloons.11 cases of TCCF were treated by detachable balloons, and 5 cases of fistulas were found spontaneously closed by DSA after 1-3 months.There was no disability rate and mortality in this study. Conclusion: TON combined with carotid artery injury was a critical situation, and sometime without obvious symptoms and sign, which was easily miss diagnosed.It should be with more concern in diagnosing and treating in such cases, to avoid disability rate and mortality.

[Experience of wound treatment on extremely severe mass burn patients involved in August 2nd Kunshan factory aluminum dust explosion accident]

Objective: To explore experience of wound treatment of extremely severe mass burn patients involved in August 2nd Kunshan factory aluminum dust explosion accident. Methods: On August 2nd, 2014, 98 extremely severe burn mass patients involved in August 2nd Kunshan factory aluminum dust explosion accident were admitted to 20 hospitals in China. The patients with complete medical record were enrolled in the study and divided into microskin graft group with 56 patients and Meek skin graft group with 42 patients. Split-thickness skin in area of residual skin were resected to repair wounds of patients in microskin graft group and Meek skin graft group by microskin grafting and Meek miniature skin grafting, respectively. The residual wound size on 28 days post injury and wound infection after skin grafting of patients in the two groups, and position of donor site of all patients were retrospectively analyzed. Data were processed with t test and chi-square test. Results: The size of residual wound of patients in Meek skin graft group on 28 days post injury was (59±13)% total body surface area (TBSA), which was obviously smaller than that in microskin graft group [(70±14)%TBSA, t=4.379, P<0.05]. Twenty-nine patients in microskin graft group and 11 patients in Meek skin graft group suffered from obvious wound infection after skin grafting. Wounds of patients in two groups were repaired with residual skin around wound in head, trunk, groin, armpit, and uncommon donor sites of scrotum (4 patients), vola (10 patients), and toe or finger web (8 patients). Conclusions: Meek skin graft is the first choice for wound repair of extremely severe burn mass patients, with faster wound healing, less wound infection. Uncommon donor sites of scrotum, vola, and toe or finger web can also be used for wound repair in case of lack of skin.

[Model and enlightenment from rescue of August 2nd Kunshan explosion casualty]

On August 2nd, 2014, a massive dust explosion occurred in a factory of Kunshan, resulting in a mass casualty involving 185 burn patients. They were transported to 20 medical institutions in Jiangsu province and Shanghai. More than one thousand of medical personnel of our country participated in this emergency rescue, and satisfactory results were achieved. In this paper, the characteristics of this accident were analyzed, the positive effects of interdisciplinary cooperation were affirmed, and the contingency plan, rescue process and pattern, and reserve, organization and management of talents during this rescue process were reviewed retrospectively.

A novel role of kukoamine B: Inhibition of the inflammatory response in the livers of lipopolysaccharide-induced septic mice via its unique property of combining with lipopolysaccharide

Kukoamine B (KB), derived from the traditional Chinese herb cortex Lycii, exerts anti-inflammatory effects due to its potent affinity with lipopolysaccharide (LPS) and CpG DNA; however, little is known regarding whether the in vivo administration of KB can effectively inhibit inflammation in septic mice. The present study thus aimed to investigate the inhibitory effects of KB on the inflammatory response in the livers of LPS-induced septic mice. KB treatment in the LPS-induced septic mice significantly decreased the plasma level of LPS. In addition, KB protected against liver injury, as confirmed by improved histology and decreased aminotransferase levels in the serum. Further experiments revealed that KB attenuated liver myeloperoxidase activity and reduced the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1. These effects were accompanied by decreases in the levels of tumor necrosis factor α and interleukin-1β in the liver tissue. In parallel, the activity of nuclear factor-κ-gene binding (NF-κB) in the livers of LPS-induced septic mice was markedly inhibited with KB treatment. In combination, these results demonstrate that KB inhibits inflammation in septic mice by reducing the concentrations of plasma LPS, decreasing leukocyte sequestration and interfering with NF-κB activation, and, therefore, suppressing the pro-adhesive phenotype of endothelial cells.

Regulatory effect and mechanisms of carbon monoxide-releasing molecule II on hepatic energy metabolism in septic mice

AIM: To investigate the possible mechanisms of exogenous carbon monoxide-releasing molecule II (CORM-2) intervention on hepatic energy metabolism in experimental sepsis.

METHODS: Forty-eight C57BL/6 mice were randomly divided into four groups (n = 12): sham group; cecal ligation and puncture (CLP) group; CLP + CORM-2 group and CLP + iCORM-2 (inactive CORM-2) group. Survival rates were determined after 72 h. Twenty-four similarly treated mice (n = 6 in each group) were assayed for post-operative continuous blood glucose in the first 36 h. Thirty-six similarly treated mice (n = 9 in each group) underwent micro-positron emission tomography (PET) scanning after tail vein injection of ¹⁸F-fluorodeoxyglucose (FDG) 24 h after operation. Plasma and liver specimens were collected for assay of liver pathology, alanine transaminase (ALT) and aspartate transaminase (AST) activities. Hepatic glucokinase activity, lactic acid levels and mitochondrial swelling were also determined.

RESULTS: Improved survival was observed in CORM-2 treated mice. Both the CLP and CLP + CORM-2 groups had sustained low blood glucose levels within the first post-operative 36 h. ¹⁸F-FDG micro-PET images showed abnormally high levels of hepatic glucose metabolism (standardized uptake value) in the CLP group (2.76 ± 0.39 vs 0.84 ± 0.14, P < 0.01), which declined to normal levels after CORM-2 intervention (1.29 ± 0.32 vs 2.76 ± 0.39, P < 0.05). glucokinase activity was markedly increased in the CLP group (6.38 ± 0.56 U/g vs 4.60 ± 0.21 U/g, P < 0.01), but was normal after CORM-2 intervention (4.74 ± 0.14 U/g vs 6.38 ± 0.56 U/g, P < 0.05). CORM-2 suppressed plasma lactic acid levels (4.02 ± 0.02 mmol/L vs 7.72 ± 2.37 mmol/L, P < 0.05) and protected hepatic mitochondria in CLP mice. CORM-2 intervention also reduced elevated plasma AST (199.67 ± 11.08 U/L vs 379.67 ± 16.34 U/L, P < 0.05) and ALT (63.67 ± 12.23 U/L vs 112.67 ± 9.74 U/L, P < 0.05) activities in CLP mice.

CONCLUSION: The release of CO molecules by CORM-2 protects mitochondria and maintains a stable level of hepatic glucose metabolism. Thus, CORM-2 improves liver function and survival in septic mice.

Exogenous carbon monoxide attenuates inflammatory responses in the small intestine of septic mice

AIM: To determine whether the carbon monoxide (CO)-releasing molecules (CORM)-liberated CO suppress inflammatory responses in the small intestine of septic mice.

METHODS: The C57BL/6 mice (male, n = 36; weight 20 ± 2 g) were assigned to four groups in three respective experiments. Sepsis in mice was induced by cecal ligation and puncture (CLP) (24 h). Tricarbonyldichlororuthenium (II) dimer (CORM-2) (8 mg/kg, i.v.) was administrated immediately after induction of CLP. The levels of inflammatory cytokines [interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α)] in tissue homogenates were measured with enzyme-linked immunosorbent assay. The levels of malondialdehyde (MDA) in the tissues were determined. The levels of nitric oxide (NO) in tissue homogenate were measured and the expression levels of intercellular adhesion molecule 1 (ICAM-1) and inducible nitric oxide synthase (iNOS) in the small intestine were also assessed. NO and IL-8 levels in the supernatants were determined after the human adenocarcinoma cell line Caco-2 was stimulated by lipopolysaccharide (LPS) (10 g/mL) for 4 h in vitro.

RESULTS: At 24 h after CLP, histological analysis showed that the ileum and jejunum from CLP mice induced severe edema and sloughing of the villous tips, as well as infiltration of inflammatory cells into the mucosa. Semi-quantitative analysis of histological samples of ileum and jejunum showed that granulocyte infiltration in the septic mice was significantly increased compared to that in the sham group. Administration of CORM-2 significantly decreased granulocyte infiltration. At 24 h after CLP, the tissue MDA levels in the mid-ileum and mid-jejunum significantly increased compared to the sham animals (103.68 ± 23.88 nmol/mL vs 39.66 ± 8.23 nmol/mL, 89.66 ± 9.98 nmol/mL vs 32.32 ± 7.43 nmol/mL, P < 0.01). In vitro administration of CORM-2, tissue MDA levels were significantly decreased (50.65 ± 11.46 nmol/mL, 59.32 ± 6.62 nmol/mL, P < 0.05). Meanwhile, the tissue IL-1β and TNF-α levels in the mid-ileum significantly increased compared to the sham animals (6.66 ± 1.09 pg/mL vs 1.67 ± 0.45 pg/mL, 19.34 ± 3.99 pg/mL vs 3.98 ± 0.87 pg/mL, P < 0.01). In vitro administration of CORM-2, tissue IL-1β and TNF-α levels were significantly decreased (3.87 ± 1.08 pg/mL, 10.45 ± 2.48 pg/mL, P < 0.05). The levels of NO in mid-ileum and mid-jejunum tissue homogenate were also decreased (14.69 ± 2.45 nmol/mL vs 24.36 ± 2.97 nmol/mL, 18.47 ± 2.47 nmol/mL vs 27.33 ± 3.87 nmol/mL, P < 0.05). The expression of iNOS and ICAM-1 in the mid-ileum of septic mice at 24 h after CLP induction significantly increased compared to the sham animals. In vitro administration of CORM-2, expression of iNOS and ICAM-1 were significantly decreased. In parallel, the levels of NO and IL-8 in the supernatants of Caco-2 stimulated by LPS was markedly decreased in CORM-2-treated Caco-2 cells (2.22 ± 0.12 nmol/mL vs 6.25 ± 1.69 nmol/mL, 24.97 ± 3.01 pg/mL vs 49.45 ± 5.11 pg/mL, P < 0.05).

CONCLUSION: CORM-released CO attenuates the inflammatory cytokine production (IL-1β and TNF-α), and suppress the oxidative stress in the small intestine during sepsis by interfering with protein expression of ICAM-1 and iNOS.

[Inhibitory effect of extrinsic CO-releasing molecules-2 (CORM-2) on inflammatory responses in mice with LPS-induced acute lung injury]

OBJECTIVE

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.

METHODS

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.

RESULT

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.

CONCLUSION

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.

[Inhibitive effect of exogenous carbon monoxide-releasing molecules 2 on tissue factor expression in sepsis]

OBJECTIVE

To explore the inhibitive effects of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on expression of tissue factor (TF) in sepsis.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Carbon monoxide releasing molecules: new insights for anticoagulation strategy in sepsis

Sepsis is a common and serious medical condition caused by hemorrhage, trauma, or abdominal surgery. Despite new understanding and much progress in therapies that specifically interfere with an interesting target, sepsis remains the leading causes of death in critically ill patients. Various therapies have been studied, but the majority of these treatments fail in clinical trials. It is clear that all septic patients exhibit coagulation abnormalities. These abnormalities range from subtle to marked activation of coagulation system, and finally to fulminant DIC. Studies confirmed that carbon monoxide has important cytoprotective function and anti-inflammatory properties. Until now, the question of whether CO plays a critical role in improving the coagulation system and then decreasing mortality during sepsis has not yet been definitely answered. Attempts to confirm this strategy may lead to new directions in the study of treatment of sepsis and the development of a novel agent for this disorder.

CO liberated from CORM-2 modulates the inflammatory response in the liver of thermally injured mice

AIM

To explore the effects of CO-releasing molecules [tricarbonyldichlororuthenium (II) dimer, CORM-2]-liberated CO on attenuation of inflammatory responses in liver of an experimental animal model of thermal injury and to investigate the associated potential mechanisms.

METHODS

Thirty-six mice were assigned to three groups in three respective experiments. In each experiment, mice in sham group (n=4) received sham thermal injury, whereas mice in burn group (n=4) received a 15% of total body surface area (TBSA) full-thickness thermal injury, and mice in burn+CORM-2 group (n=4) received the same thermal injury with immediate administration of CORM-2 (8 mg/kg, iv). Hepatic tissue sections were stained with hematoxylin and eosin and examined under a light microscope. Levels of aminotransferases (ALT and AST) and nitric oxide (NO) were measured by biochemical methods. Tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL-1beta) activity, and the protein expression of iNOS and HO-1 in serum and tissue homogenates were assessed. In in vitro experiments, Kupffer cells were stimulated with LPS (10 microg/mL) for 4 h in the presence or absence of CORM-2 (10-100 micromol/L). Subsequently, the expression levels of TNF-alpha and NO production were assessed.

RESULTS

Pro-inflammatory mediators (TNF-alpha, IL-1beta, NO) in serum and liver homogenates of thermally injured mice were significantly reduced by CORM-2 administration. This was accompanied by a decrease in the expression of iNOS while an increase in the expression of HO-1 in the liver tissue. In parallel, the concentrations of TNF-alpha and NO in supernatants of LPS-stimulated Kupffer cells co-incubated with CORM-2 (10-100 micromol/L) were also markedly decreased. Histological examination demonstrated that CORM-2 could attenuate the leukocytes infiltration to the liver tissue.

CONCLUSION

CORM-released CO modulates liver inflammation and significantly protects liver injury in burn mice by inhibiting the expression of iNOS and NO production, down-regulating the expression of pro-inflammatory mediators (TNF-alpha, IL-1beta).

Carbon liberated from CO-releasing molecules attenuates leukocyte infiltration in the small intestine of thermally injured mice

AIM

To determine whether Carbon (CO) liberated from CO-releasing molecules attenuates leukocyte infiltration in the small intestine of thermally injured mice.

METHODS

Thirty-six mice were assigned to four groups. Mice in the sham group (n = 9) were underwent to sham thermal injury; mice in the burn group (n = 9) received 15% total body surface area full-thickness thermal injury; mice in the burn + CORM-2 group (n = 9) were underwent to the same thermal injury with immediate administration of tricarbonyldichlororuthenium (II) dimer CORM-2 (8 mg/kg, i.v.); and mice in the burn+DMSO group (n = 9) were underwent to the same thermal injury with immediate administration of 160 muL bolus injection of 0.5% DMSO/saline. Histological alterations and granulocyte infiltration of the small intestine were assessed. Polymorphonuclear neutrophil (PMN) accumulation (myeloperoxidase assay) was assessed in mice mid-ileum. Activation of nuclear factor (NF)-kappa B, expression levels of intercellular adhesion molecule-1 (ICAM-1) and inducible heme oxygenase in mid-ileum were assessed.

RESULTS

Treatment of thermally injured mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-kappa B in the small intestine. This was accompanied by a decrease in the expression of ICAM-1. In parallel, burn-induced granulocyte infiltration in mid-ileum was markedly decreased in the burn mice treated with CORM-2.

CONCLUSION

CORM-released CO attenuates leukocyte infiltration in the small intestine of thermally injured mice by interfering with NF-kappa B activation and protein expression of ICAM-1, and therefore suppressing the pro-adhesive phenotype of endothelial cells.

CO liberated from CORM-2 modulates the inflammatory response in the liver of thermally injured mice

AIM: To explore the effects of CO-releasing molecules [tricarbonyldichlororuthenium (II) dimer, CORM-2]-liberated CO on attenuation of inflammatory responses in liver of an experimental animal model of thermal injury and to investigate the associated potential mechanisms.

METHODS: Thirty-six mice were assigned to three groups in three respective experiments. In each experiment, mice in sham group (n = 4) received sham thermal injury, whereas mice in burn group (n = 4) received a 15% of total body surface area (TBSA) full-thickness thermal injury, and mice in burn + CORM-2 group (n = 4) received the same thermal injury with immediate administration of CORM-2 (8 mg/kg, iv). Hepatic tissue sections were stained with hematoxylin and eosin and examined under a light microscope. Levels of aminotransferases (ALT and AST) and nitric oxide (NO) were measured by biochemical methods. Tumor necrosis factor-α (TNF-α) and interleukin (IL-1β) activity, and the protein expression of iNOS and HO-1 in serum and tissue homogenates were assessed. In in vitro experiments, Kupffer cells were stimulated with LPS (10 &mgr;g/mL) for 4 h in the presence or absence of CORM-2 (10-100 &mgr;mol/L). Subsequently, the expression levels of TNF-α and NO production were assessed.

RESULTS: Pro-inflammatory mediators (TNF-α, IL-1β, NO) in serum and liver homogenates of thermally injured mice were significantly reduced by CORM-2 administration. This was accompanied by a decrease in the expression of iNOS while an increase in the expression of HO-1 in the liver tissue. In parallel, the concentrations of TNF-α and NO in supernatants of LPS-stimulated Kupffer cells co-incubated with CORM-2 (10-100 &mgr;mol/L) were also markedly decreased. Histological examination demonstrated that CORM-2 could attenuate the leukocytes infiltration to the liver tissue.

CONCLUSION: CORM-released CO modulates liver inflammation and significantly protects liver injury in burn mice by inhibiting the expression of iNOS and NO production, down-regulating the expression of pro-inflammatory mediators (TNF-α, IL-1β).

Carbon liberated from CO-releasing molecules attenuates leukocyte infiltration in the small intestine of thermally injured mice

AIM: To determine whether Carbon (CO) liberated from CO-releasing molecules attenuates leukocyte infiltration in the small intestine of thermally injured mice.

METHODS: Thirty-six mice were assigned to four groups. Mice in the sham group (n = 9) were underwent to sham thermal injury; mice in the burn group (n = 9) received 15% total body surface area full-thickness thermal injury; mice in the burn + CORM-2 group (n = 9) were underwent to the same thermal injury with immediate administration of tricarbonyldichlororuthenium (II) dimer CORM-2 (8 mg/kg, i.v.); and mice in the burn+DMSO group (n = 9) were underwent to the same thermal injury with immediate administration of 160 μL bolus injection of 0.5% DMSO/saline. Histological alterations and granulocyte infiltration of the small intestine were assessed. Polymorphonuclear neutrophil (PMN) accumulation (myeloperoxidase assay) was assessed in mice mid-ileum. Activation of nuclear factor (NF)-κΒ, expression levels of intercellular adhesion molecule-1 (ICAM-1) and inducible heme oxygenase in mid-ileum were assessed.

RESULTS: Treatment of thermally injured mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-κΒ in the small intestine. This was accompanied by a decrease in the expression of ICAM-1. In parallel, burn-induced granulocyte infiltration in mid-ileum was markedly decreased in the burn mice treated with CORM-2.

CONCLUSION: CORM-released CO attenuates leukocyte infiltration in the small intestine of thermally injured mice by interfering with NF-κΒ activation and protein expression of ICAM-1, and therefore suppressing the pro-adhesive phenotype of endothelial cells.

[Molecular mechanism of inhibition of early pulmonary injury and inflammatory response by exogenous carbon monoxide: experiment with mice]

OBJECTIVE

To investigate the effect of determine whether the CO-releasing molecules-liberated CO could attenuate leukocytes sequestration and the inflammatory response in the lung of thermally injured mice.

METHODS

Thirty-six C57BL/6 mice were randomly divided into 3 groups: burn group, burned with hot water on the back skin with an area as large as 15% of the total body surface area with the hair shed so as o cause full-thickness thermal injury, CORM-2 group, undergoing the same thermal injury and then receiving intravenous injection of CORM-2 immediately, and sham operation group, undergoing sham thermal injury. Twenty-four hours later the mice were killed. The myeloperoxidase enzyme (MPO) level in lung tissue was detected. Evans blue test and lung wet/dry weight ratio were used to examine the lung edema degree. Bronchoalveolar lavage (BAL) fluid was collected to undergo ELISA to detect the tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta. Activation of nuclear factor (NF)-kappaB was detected with electrophoretic mobility shift assay. The expression level of intercellular adhesion molecule-1, ICAM-1) in the lung was assessed by Western blotting. Whole blood samples were collected from the left ventricles. Serum was isolated and used to stimulated lung endothelial cells for 4 h. Polymorphonuclear neutrophilic leukocytes (PMNs) were isolated from mice bone marrow, labeled with Na(51)CrO(4), cultured, and added with the murine lung endothelial cells (MLECs) stimulated by serums from the mice of the 3 groups so as to measure leukocyte adhesion.

RESULTS

The MPO activity of the CORM-2 group was (42 +/- 7) U/g tissue, significantly lower than that of the burn group [(87 +/- 11) U/g tissue, P < 0.05]. The Evans blue extraction level of the CORM-1 group was (53.1 +/- 4.6), not significantly different from that of the burn group [(55.1 +/- 3.8), P > 0.05], however, still significantly higher than that of the sham group [(8.8 +/- 1.3), P < 0.05]. The wet/dry weight ratio of the CORM-2 group was 4.80 +/- 0.11, significantly higher than that of the sham group (3.20 +/- 0.07, P < 0.05), but not significantly different from that of the burn group (4.70 +/- 0.18, P > 0.05). The TNF-alpha and IL-1beta levels of the CORM-2 group were (92 +/- 4) pg/ml and (27.2 +/- 2.9) pg/ml respectively, both significantly higher than those of the sham group [(24 +/- 4) pg/ml and (6.6 +/- 1.0) pg/ml respectively, both P < 0.05], but significantly lower that those of the burn group [(160 +/- 9) pg/ml and (27.2 +/- 2.9) pg/ml respectively, both P < 0.05]. The A value for the lung ICAM-1 protein level of the CORM-1 group was (2.4 +/- 0.4), significantly higher than that of the sham group [(1.4 +/- 0.6)], however, significantly lower than that of the burn group [(3.5 +/- 1.1), P < 0.05]. The lung NF-kappaB activity of the CORM-1 group was significantly lower than that of the burn group. The PMN adhesion to the MLECs stimulated by the CORM-2-treated thermally injured mice serum was (25.4 +/- 5.6)%, significantly lower than that of the burn group [(46.5 +/- 8.5)%, P < 0.05]. Also, CORM-2 markedly decreased the production of inflammatory mediators in BAL fluid without suppressing the permeability of pulmonary microcirculation.

CONCLUSION

CORM-released CO attenuates the inflammatory response in the lung of thermally injured mice by decreasing leukocyte sequestration and interfering with NF-kappaB activation, protein expression of ICAM-1, thus suppressing endothelial cells pro-adhesive phenotype.

[The inhibitory effects of extrinsic carbon monoxide-releasing molecules II on inflammatory responses in liver of mice with severe burns]

OBJECTIVE

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.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

Attenuation of leukocytes sequestration by carbon monoxide-releasing molecules: liberated carbon monoxide in the liver of thermally injured mice

We sought to determine whether the CO-releasing molecules, ie, liberated CO, attenuates the leukocytes sequestration in the liver of thermally injured mice. Sixty-five mice were assigned to five groups in three respective experiments. In each experiment, mice in sham group (n = 7) and sham + CORM-2 group (n = 7) were underwent sham thermal injury, whereas mice in burn group (n = 7) received 15% TBSA full-thickness thermal injury, mice in burn + CORM-2 group (n = 7) underwent the same thermal injury with the immediate administration of CORM-2 (8 mg/kg intravenously), and mice in burn + DMSO group (n = 7) underwent the same thermal injury with an immediate 160 microl-bolus injection of 0.5% dimethyl sulfoxide/saline. Polymorphonuclear leucocyte (PMN) accumulation (assessed by the myeloperoxidase assay) was assessed in mice liver. Activation of nuclear factor kappa B (NF-kappaB) and the expression levels of ICAM-1 and VCAM-1 in liver were assessed. In an in vitro experiment, sinusoidal endothelial cells (SECs) isolated from the liver of normal mice were stimulated by experimental mice serum (50% v/v) for 4 hours. Subsequently, the adhesion of PMNs to SECs was assessed. In addition, the number and states (rolling or stationary) of leukocytes in liver were observed by intravital microscopy. Treatment of thermally injured mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-kappaB in the liver, which was accompanied by a decrease of the expression of ICAM-1 and VCAM-1. In parallel, PMNs adhesion to SECs stimulated by CORM-2-treated thermally injured mice serum was markedly decreased. Intravital microscopy showed that the stationary leukocytes in thermally injured mice liver were significantly reduced by treatment of CORM-2. CORM-released CO attenuates leukocytes sequestration in the liver of burn mice by interfering with NF-kappaB activation, protein expression of ICAM-1 and VCAM-1, and therefore suppressing endothelial cells proadhesive phenotype.

Apoptosis and functional changes of dipeptide transporter (PepT1) in the rat small intestine after traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) can induce significant alterations of intestinal mucosal structure and barrier function. However, it has not been investigated whether, and to what degree, apoptosis and alterations of absorptive function in the intestinal mucosal epithelium occur after TBI.

MATERIAL AND METHODS

Male Wistar rats were randomly divided into seven groups (five rats each group) including normal group, control group with sham operation, and TBI groups at hours 3, 12, 24, and 72, and on day 7. Parietal brain contusion was adopted using weight-dropping method. Intestinal mucosal structure was examined using histomorphmetric study and electron microscopy, and apoptosis was detected by TUNEL method. An everted sleeve of intestine was securely incubated in Kreb's solution with radioactive dipeptide ((3)H-Gly-Sar, 10 microCi/mL) to measure the uptake and transport of PepT1 of small intestinal epithelial cells.

RESULTS

The villous height, crypt depth and surface area were significantly decreased at 24 h after TBI, and further declined to the degree of mucosal atrophy on day 7 after TBI. Apoptotic changes of condensed nuclei in epithelial cells and fractured, distorted, and sparse microvilli were found by electron microscopy. The number of apoptotic cells in the mucosal epithelium was significantly increased since 3 h after TBI, peaked at 72 h post-injury, then declined at 7 days, but was still higher than that of control. There was a highly negative relation between the apoptotic index and the villous height, the crypt depth, and villous surface area. Compared with that of normal and control rats, the transport and uptake of dipeptide was significantly increased at 3 h post-injury (P < 0.01), peaked at 12 h and declined a bit at 24 h post-injury, and returned to the level of normal and control rats at 72 h and 7 days.

CONCLUSIONS

It is highly suggested that intestinal mucosa apoptosis plays an important role in the pathogenesis of acute gut damage after TBI. Intestinal PepT1 expression could be up-regulated after traumatic brain injury, and maintained the normal level under the condition of serious intestinal damage. Up-regulation of PepT1 may adaptively improve absorption of di- and tripeptides, independent of changes in the mucosal surface area.

Management of Severe Burn Injuries in Neonates

Although rare, burns suffered by neonates can be fatal. Many complex difficulties are faced during the management of burns in neonates because of the neonate's complex physiological and pathological changes. We compiled a retrospective review from the treatment of four burned neonates (including a premature neonate). All four neonates suffered bath-related burns in the hospital as a result of careless nursing when being bathed. The total body surface area burned ranged from 1 to 60% in these patients, and all survived the burn injury. All the patients were treated in the Burn Intensive Care Unit with close co-operation of burn surgeons and neonatologists. Based on our experience as well as a review of literature, management recommendations are proposed as the following: 1) prompt and aggressive fluid resuscitation, 2) early administration of oxygen and keeping the patient warm, 3) application of specific biological dressing and recombinant human growth hormone if necessary, 4) establishment of a multidisciplinary team, and 5) removal of necrosis tissue early and aggressively. Furthermore, a very important issue is also discussed, which is about the prevention of newborn burns in the neonate unit in developing countries.

Changes of biological functions of dipeptide transporter (PepT1) and hormonal regulation in severe scald rats

AIM: To determine the regulatory effects of recombinant human growth hormone (rhGH) on dipeptide transport (PepT1) in normal and severe scald rats.

METHODS: Male Sprague-Dawley rats with 30% total body surface area (TBSA)IIIdegree scald were employed as the model. In this study rhGH was used at the dose of 2 IU.kg^-1d^-1. An everted sleeve of intestine 4 cm long obtained from mid-jejunum was securely incubated in Kreb’s solution with radioactive dipeptide (³H-glycylsarcosine, ³H-Gly-Sar, 10 μCi/ml) at 37 °C for 15 min to measure the effects of uptake and transport of PepT1 of small intestinal epithelial cells in normal and severe scald rats.

RESULTS: Abundant blood supply to intestine and mesentery was observed in normal and scald rats administered rhGH, while less supply of blood to intestine and mesentery was observed in rats without rhGH. Compared with controls, the transport of dipeptide in normal rats with injection of rhGH was not significantly increased (P = 0.1926), while the uptake was significantly increased (P = 0.0253). The effects of transport and uptake of PepT1 in scald rats with injection of rhGH were significantly increased (P = 0.0082, 0.0391).

CONCLUSION: Blood supply to intestine and mesentery of rats was increased following injection of rhGH. The effects of uptake and transport of dipeptide transporters in small intestinal epithelial cells of rats with severe scald were markedly up-regulated by rhGH.

Hormonal regulation of dipeptide transporter (PepT1) in Caco-2 cells with normal and anoxia/reoxygenation management

AIM: To determine the regulation effects of recombinant human growth hormone (rhGH) on dipeptide transporter (PepT1) in Caco-2 cells with normal culture and anoxia/reoxygenation injury.

METHODS: A human intestinal cell monolayer (Caco-2) was used as the in vitro model of human small intestine and cephalexin as the model substrate for dipeptide transporter (PepT1). Caco-2 cells grown on Transwell membrane filters were preincubated in the presence of rhGH in the culture medium for 4 d, serum was withdrawn from monolayers for 24 h before each experiment. The transport experiments of cephalexin across apical membromes were then conducted; Caco-2 cells grown on multiple well dishes (24 pore) with normal culture or anoxia/reoxygenation injury were preincubated with rhGH as above and uptake of cephalexin was then measured.

RESULTS: The transport and uptake of cephelaxin across apical membranes of Caco-2 cells after preincubation with rhGH were significantly increased compared with controls (P = 0.045, 0.0223). Also, addition of rhGH at physiological concentration (34 nM) to incubation medium greatly stimulates cephalexin uptake by anoxia/reoxygenation injuried Caco-2 cells (P = 0.0116), while the biological functions of PepT1 in injured Caco-2 cells without rhGH were markedly downregulated. Northern blot analysis showed that the level of PepT1 mRNA of rhGH-treated injured Caco-2 cells was greatly increased compared to controls.

CONCLUSION: The present results of rhGH stimulating the uptake and transport of cephalexin indicated that rhGH greatly upregulates the physiological effects of dipeptide transporters of Caco-2 cells. The alteration in the gene expression may be a mechanism of regulation of PepT1. In addition, Caco-2 cells take up cephalexin by the Proton-dependent dipeptide transporters that closely resembles the transporters present in the intestine. Caco-2 cells represent an ideal cellular model for future studies of the dipeptide transporter.

Molecularly imprinted polymer using-p-hydroxybenzoic acid, p-hydroxyphenylacetic acid and p-hydroxyphenylpropionic acid as templates

Molecularly imprinted polymers (MIPs) using p-hydroxybenzoic acid (p-HB), p-hydroxyphenylacetic acid (p-HPA) and p-hydroxyphenylpropionic acid (p-HPPA) as templates were synthesized. The performance of the templates and their analogues on polymer-based high performance liquid chromatography (HPLC) columns was studied. The imprinting effect of the MIP using p-HB as template is more obvious than that of MIP using either p-HPA or p-HPPA as template, and the mixture of p-HB and p-HPA can be well separated on the MIP using p-HB as template, but not on the blank. Interestingly, the recognition of MIP (p-HB as the template) to p-HB showed a synergistic effect. The retention factor of p-HB is not the sum of those of phenol and benzoic acid. We also found that the imprinting effect decreased when increasing the concentration of acetic acid in mobile phase. The possible reason is that acetic acid molecules occupied the binding sites of the polymer, thereby decreasing the concentration of binding sites. Furthermore, polymers, which showed specificity to 3,4-dihydroxybenzoic acid, can be prepared with p-HB as template. It is thus possible to synthesize a specific polymer for a compound that is either expensive or unstable by using a structurally similar compound as template.