Electrotaxis of alveolar epithelial cells in direct-current electric fields / 中华创伤杂志(英文版)

PURPOSE@#This study aims to elucidate the electrotaxis response of alveolar epithelial cells (AECs) in direct-current electric fields (EFs), explore the impact of EFs on the cell fate of AECs, and lay the foundation for future exploitation of EFs for the treatment of acute lung injury.@*METHODS@#AECs were extracted from rat lung tissues using magnetic-activated cell sorting. To elucidate the electrotaxis responses of AECs, different voltages of EFs (0, 50, 100, and 200 mV/mm) were applied to two types of AECs, respectively. Cell migrations were recorded and trajectories were pooled to better demonstrate cellular activities through graphs. Cell directionality was calculated as the cosine value of the angle formed by the EF vector and cell migration. To further demonstrate the impact of EFs on the pulmonary tissue, the human bronchial epithelial cells transformed with Ad12-SV40 2B (BEAS-2B cells) were obtained and experimented under the same conditions as AECs. To determine the influence on cell fate, cells underwent electric stimulation were collected to perform Western blot analysis.@*RESULTS@#The successful separation and culturing of AECs were confirmed through immunofluorescence staining. Compared with the control, AECs in EFs demonstrated a significant directionality in a voltage-dependent way. In general, type Ⅰ alveolar epithelial cells migrated faster than type Ⅱ alveolar epithelial cells, and under EFs, these two types of cells exhibited different response threshold. For type Ⅱ alveolar epithelial cells, only EFs at 200 mV/mm resulted a significant difference to the velocity, whereas for, EFs at both 100 mV/mm and 200 mV/mm gave rise to a significant difference. Western blotting suggested that EFs led to an increased expression of a AKT and myeloid leukemia 1 and a decreased expression of Bcl-2-associated X protein and Bcl-2-like protein 11.@*CONCLUSION@#EFs could guide and accelerate the directional migration of AECs and exert antiapoptotic effects, which indicated that EFs are important biophysical signals in the re-epithelialization of alveolar epithelium in lung injury.

Continuous purification and culture of rat type 1 and type 2 alveolar epithelial cells by magnetic cell sorting / 中华创伤杂志(英文版)

PURPOSE@#The incidence of acute lung injury (ALI) in severe trauma patients is 48% and the mortality rate following acute respiratory distress syndrome evolved from ALI is up to 68.5%. Alveolar epithelial type 1 cells (AEC1s) and type 2 cells (AEC2s) are the key cells in the repair of injured lungs as well as fetal lung development. Therefore, the purification and culture of AEC1s and AEC2s play an important role in the research of repair and regeneration of lung tissue.@*METHODS@#Sprague-Dawley rats (3-4 weeks, 120-150 g) were purchased for experiment. Dispase and DNase I were jointly used to digest lung tissue to obtain a single-cell suspension of whole lung cells, and then magnetic bead cell sorting was performed to isolate T1α positive cells as AEC1s from the single-cell suspension by using polyclonal rabbit anti-T1a (a specific AEC1s membrane protein) antibodies combined with anti-rabbit IgG microbeads. Afterwards, alveolar epithelial cell membrane marker protein EpCAM was designed as a key label to sort AEC2s from the remaining T1α-neg cells by another positive immunomagnetic selection using monoclonal mouse anti-EpCAM antibodies and anti-mouse IgG microbeads. Cell purity was identified by immunofluorescence staining and flow cytometry.@*RESULTS@#The purity of AEC1s and AEC2s was 88.3% ± 3.8% and 92.6% ± 2.7%, respectively. The cell growth was observed as follows: AEC1s stretched within the 12-16 h, but the cells proliferated slowly; while AEC2s began to stretch after 24 h and proliferated rapidly from the 2nd day and began to differentiate after 3 days.@*CONCLUSION@#AEC1s and AEC2s sorted by this method have high purity and good viability. Therefore, our method provides a new approach for the isolation and culture of AEC1s and AEC2s as well as a new strategy for the research of lung repair and regeneration.

Effects and mechanism of hydrogen peroxide pretreatment with low molarity on oxidative stress induced apoptosis of mouse bone marrow mesenchymal stem cells / 中华烧伤杂志

Objective: To investigate the effects and mechanism of hydrogen peroxide (HP) pretreatment with low molarity on oxidative stress induced apoptosis of mouse bone marrow mesenchymal stem cells (BMSCs). Methods: The experimental research methods were used. BMSCs were isolated and cultured from two 2-week-old male BALB/c mice by the whole bone marrow culture method. The 3rd-7th passages of cells in logarithmic growth phase were used for the experiments after identification. According to the random number table (the same grouping method below), the cells were divided into 0 μmol/L HP group (without HP, the same below), 25 μmol/L HP group, 50 μmol/L HP group, 100 μmol/L HP group, 150 μmol/L HP group, 200 μmol/L HP group, 250 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respectively. The apoptosis rate was detected by flow cytometry (n=4) after 24 hours of culture. The cells were divided into 0 μmol/L HP group, 25 μmol/L HP group, 50 μmol/L HP group, and 100 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respeclively. After 24 hours of culture, the protein expressions of B-lymphoma-2 (Bcl-2) and Bcl-2-related X protein (Bax) were detected by Western blotting, and the Bcl-2/Bax ratio was calculated (n=3). The cells were divided into 0 μmol/L HP group, 25 μmol/L HP group, 50 μmol/L HP group, 100 μmol/L HP group, 200 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respectively. After 24 hours of culture, the protein expressions of glycogen synthase kinase-3β (GSK-3β) and phosphorylated GSK-3β (p-GSK-3β) were detected by Western blotting (n=3). The cells were divided into 0 μmol/L HP group, 50 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respeclively, and HP pretreatment group with 50 μmol/L HP being added in advance for 12 h and then 300 μmol/L HP being added. After 24 hours of culture, the morphology and growth of cells were observed by inverted fluorescence microscopy (non-fluorescent condition) and immunofluorescence method, the apoptosis rate was detected by flow cytometry, the protein expressions of Bcl-2, Bax, cysteine aspartic acid specific protease-3 (caspase-3), caspase-9, cleavage caspase-3, cleavage caspase-9, GSK-3β, and p-GSK-3β were detected by Western blotting, and the Bcl-2/Bax ratio was calculated, with all the number of samples being 3. Data were statistically analyzed with one-way analysis of variance and Bonferroni test. Results: After 24 hours of culture, compared with that in 0 μmol/L HP group, the apoptosis rate of cells did not change significantly in 25 μmol/L HP group, 50 μmol/L HP group, or 100 μmol/L HP group (P>0.05) but increased significantly in 150 μmol/L HP group, 200 μmol/L HP group, 250 μmol/L HP group, and 300 μmol/L HP group (P<0.01). After 24 hours of culture, compared with that in 0 μmol/L HP group, the Bcl-2/Bax ratio of cells increased significantly in 25 μmol/L HP group and 50 μmol/L HP group (P<0.05 or P<0.01) but decreased significantly in 100 µmol/L HP group (P<0.05). After 24 hours of culture, compared with those in 0 μmol/L HP group, the protein expression of GSK-3β in cells showed no significant change in 25 μmol/L HP group and 50 μmol/L HP group (P>0.05), the protein expressions of p-GSK-3β in cells significantly increased in 25 μmol/L HP group and 50 μmol/L HP group (P<0.01), the protein expressions of GSK-3β and p-GSK-3β in cells in 100 μmol/L HP group showed no significant change (P>0.05), the protein expressions of GSK-3β in cells in 200 μmol/L HP group and 300 μmol/L HP group were significantly increased (P<0.05). but the protein expression of p-GSK-3β in cells in 200 μmol/L HP group and 300 μmol/L HP group was significantly decreased (P<0.05). After 24 hours of culture, the morphology and growth of cells in 0 μmol/L HP group and 50 μmol/L HP group were similar and normal; in contrast, the cells in 300 µmol/L HP group became smaller and round, with the cell protrusions being shorter or disappeared, the nucleus being cavitated, and the cell abscission being increased significantly; the morphology of most cells in HP pretreatment group was normal, with the shedding of cells being less than that in 300 µmol/L HP group, and the morphology of nucleus being normal. After 24 hours of culture, the protein expression of caspase-9 was similar among the four groups (P>0.05). Compared with that in 0 μmol/L HP group, the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells in 50 μmol/L HP group showed no significant changes (P>0.05), the Bcl-2/Bax ratio of cells in 50 μmol/L HP group increased significantly (P<0.05), the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells in 300 μmol/L HP group were significantly increased (P<0.01), while the Bcl-2/Bax ratio of cells in 300 μmol/L HP group was significantly decreased (P<0.05). Compared with those in 300 μmol/L HP group, the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells were significantly decreased in HP pretreatment group (P<0.05 or P<0.01), while the Bcl-2/Bax ratio of cells was significantly increased in HP pretreatment group (P<0.01). After 24 hours of culture, the protein expressions of GSK-3β and p-GSK-3β of cells in 0 μmol/L HP group, 50 μmol/L HP group, 300 μmol/L HP group, and HP pretreatment group were 1.09±0.14, 0.62±0.17, 1.35±0.21, 0.74±0.34, 0.68±0.03, 0.85±0.08, 0.38±0.10, and 0.54±0.09, respectively. Compared with those in 0 μmol/L HP group, the protein expression of p-GSK-3β of cells was significantly increased in 50 μmol/L HP group (P<0.05) but significantly decreased in 300 μmol/L HP group (P<0.01), while the protein expression of GSK-3β of cells was significantly increased in 300 μmol/L HP group (P<0.05). Compared with those in 300 μmol/L HP group, the protein expression of GSK-3β of cells was significantly decreased in HP pretreatment group (P<0.01), while the protein expression of p-GSK-3β of cells was significantly increased in HP pretreatment group (P<0.01). Conclusions: The molarity of 50 μmol/L may be the optimal molarity of HP to pretreat mouse BMSCs, and 50 μmol/L HP pretreatment can antagonize mitochondrial pathway of oxidative stress induced apoptosis by inhibiting the activity of GSK-3β.

TNF-α release capacity is suppressed immediately after hemorrhage and resuscitation / 中华创伤杂志(英文版)

<p><b>PURPOSE</b>It has been suggested that patients with traumatic insults are resuscitated into a state of an early systemic inflammatory response. We aimed to evaluate the influence of hemorrhagic shock and resuscitation (HSR) upon the inflammatory response capacity assessed by overall TNF-α secretion capacity of the host compared to its release from circulating leukocytes in peripheral circulation.</p><p><b>METHODS</b>Rats (8/group) subjected to HS (MAP of 30-35 mmHg for 90 min followed by resuscitation over 50 min) were challenged with Lipopolysaccharide (LPS), 1 μg/kg intravenously at the end of resuscitation (HSR-LPS group) or 24 h later (HSR-LPS24 group). Control animals were injected with LPS without bleeding (LPS group). Plasma TNF-α was measured at 90 min after the LPS challenge. In addition, whole blood (WB) was obtained either from healthy controls (CON) immediately after resuscitation (HSR), or at 24 h post-shock (HSR 24). WB was incubated with LPS (100 ng/mL) for 2 h at 37 °C. TNF-α concentration and LPS binding capacity (LBC) was determined.</p><p><b>RESULTS</b>Compared to LPS group, HSR followed by LPS challenge resulted in suppression of plasma TNF-α in HSR-LPS and HSR-LPS24 groups (1835 ± 478, 273 ± 77, 498 ± 200 pg/mL, respectively). Compared to CON the LPS-induced TNF-α release capacity of circulating leukocytes ex vivo was strongly declined both at the end of resuscitation (HSR) and 24 h later (HSR24) (1012 ± 259, 313 ± 154, 177 ± 63 ng TNF/mL, respectively). The LBC in WB was similar between CON and HSR and only moderately enhanced in HSR24 (57 ± 6, 56 ± 6, 71 ± 5 %, respectively).</p><p><b>CONCLUSION</b>Our data suggest that the overall inflammatory response capacity is decreased immediately after HSR, persisting up to 24 h, and is independent of LBC.</p>

Expression and significance of HIF-1α and HIF-2α in pancreatic cancer / 华中科技大学学报（医学）（英德文版）

The expression levels of hypoxia-inducible factor 1alpha (HIF-1α) and HIF-2α in pancreatic cancer (PC) and their association with clinicopathologic characteristics were investigated in order to elucidate their roles in the development of PC. HIF-1α and HIF-2α mRNA levels in 20 patients with PC were detected by quantitative real-time polymerase chain reaction. The expression of HIF-1α and HIF-2α protein in samples from other 90 patients with PC was measured by immunohistochemistry. Correlations between the expression of HIF-1α or HIF-2α and clinicopathologica features and prognosis were analyzed. The expression of both HIF-1α and HIF-2α mRNA was up-regulated in most cancer tissues (P<0.05). HIF-1α staining was weakly positive in most cancer tissues and strongly positive in adjacent pancreas tissues (P<0.05). Clinicopathologic analysis revealed that relatively strong HIF-1α expression in cancer tissues was related to greater invasion (P<0.05), higher tumor pathologic stage (P<0.05), higher American Joint Committee on Cancer (AJCC) stage (P<0.05) and shorter overall survival time (P<0.05). Conversely, HIF-2α staining was strongly positive in most cancer tissues and weakly positive in adjacent pancreas tissues. Clinicopathologic analysis revealed that relatively strong HIF-2α expression in cancer tissues was related to less invasion (P<0.05), lower tumor pathologic stage (P<0.05), lower AJCC stage (P<0.05) and longer overall survival time (P<0.05). Moreover, the HIF-1α(high)/HIF-2α(low) group showed a shorter survival time than the HIF-1α(low)/HIF-2α(high) group. In conclusion, although HIF-1α and HIF-2α mRNA expression patterns are the same, their protein expression patterns are significantly different and they play different roles in PC. Combined analysis of HIF-1α and HIF-2α expression might be useful to predict the prognosis of patients with PC.

Endogenous glucocorticoid increases the basal level of Treg-Th17 balance under early phase of stress / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To explore the changes of Treg-Th17 balance influenced by corticosterone, major effect hormone of hypothalamic-pituitary-adrenal (HPA) axis under running stress.</p><p><b>METHODS</b>A total of 25 corticotropin-releasing hormone (CRH) wildtype (CRH+/+) and knockout (CRH-/-) mice were adopt and divided into 4 groups as follows: CRH+/+ ctrl, CRH+/+ stress, CRH-/- ctrl and CRH-/- stress. All mice in stress groups were under 2 h running. After 1 h, blood plasma in all groups was collected and the expression of corticosterone and IL-17A was detected by ELISA. Meanwhile, unicell suspensions of peripheral lymph node and spleen in each group were prepared too and stained by PE-CD4 and FITC-CD25, then the changes of Treg (CD4+CD25+) in different groups were checked by flow cytometry; all data were statistically analyzed by the software of WinMDI 2.9, SPSS 11.5, Origin 7.5 and Matlab 2-D and 3-D plot function.</p><p><b>RESULTS</b>The levels of corticosterone were significantly higher in stress groups than that in corresponding control groups (P less than 0.05), especially in CRH+/+ stress group (P less than 0.01). However, the changes of Tregs were not obvious between stress groups and control groups with respective genotypes (P less than 0.05). Compared with that in CRH+/+ control group, the ratio of Treg and the expression of IL-17A in CRH-/- stress group were significantly higher than those in control group (P less than 0.05). Combined with the expression levels of corticosterone, Treg and Th17, our study suggests that endogenous glucocorticoid with basal level may cause the changes in Treg-Th17 balance. Moreover, as the corticosterone level increases, the expression of Treg and Th17 appears to manifest antagonistic fluctuant status with a rising tendency in general.</p><p><b>CONCLUSION</b>Endogenous glucocorticoid under early stage of stress may increase the function of T lymphocyte immunity to some extent.</p>

Role of tumor necrosis factor α in endothelial-mesenchymal transition in vitro / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the role of tumor necrosis factor α (TNF-α) in endothelial-mesenchymal transition (EnMT), and to explore the mechanism of fibrosis disease.</p><p><b>METHODS</b>Human umbilical vein endothelial cells (HUVEC) from umbilical cord of healthy fetus were isolated by enzymatic digestion and identified by immunofluorescence assay. The third to fifth generations of cultured HUVEC in logarithmic phase were harvested and seeded in 12-well plates and 6-well plates, and they were divided into control group (ordinary culture without any stimulation), 5, 10, 25, 50, and 100 ng/mL TNF-α groups (5, 10, 25, 50, 100 ng/mL of TNF-α was respectively added into the nutrient solution) according to the random number table, with three samples in each group. After being cultured for 72 hours, the cell morphology was observed under inverted phase-contrast microscope; the expression levels of coagulation factor VIII and α smooth muscle actin (α-SMA) were detected by immunofluorescence assay, and the ratios of numbers (absorbance values) of cells with expression of both factors were calculated. The mRNA expression levels of cadherin, α-SMA, and type I collagen were detected by RT-PCR (denoted as gray value ratio). Data were processed with one-way analysis of variance and LSD test.</p><p><b>RESULTS</b>(1) The shape of primary HUVEC was round, short-spindle, or flat, and cells grew vigorously in cobblestone appearance after passages. After being subcultured for 1, 2, 3, 4, 5 passage (s), the positive rate of coagulation factor VIII of HUVEC was respectively (85.5 ± 1.8)%, (88.1 ± 5.0)%, (93.6 ± 3.7)%, (92.9 ± 4.8)%, (89.5 ± 1.1)%, and they were significantly higher than that of primary HUVEC [(81.4 ± 3.8)%, with F values all equal to 7.481, P values all below 0.05]. (2) As compared with that in control group, the appearance of cells in 5, 10, 25, 50, and 100 ng/mL TNF-α groups was gradually transformed from round, short-spindle, or flat shape to long-spindle shape with reduced intercellular junction and larger intercellular gap along with the increase in the concentration of TNF-α. (3) The ratios of numbers and the absorbance values of coagulation factor VIII and α-SMA double positive cells in control group (0.055 ± 0.015, 0.078 ± 0.017) were significantly lower than those in 5, 10, 25, 50, and 100 ng/mL TNF-α groups (0.257 ± 0.106, 0.280 ± 0.129, 0.505 ± 0.059, 0.817 ± 0.035, 0.929 ± 0.101 and 0.437 ± 0.040, 0.456 ± 0.097, 0.496 ± 0.082, 0.787 ± 0.131, 0.885 ± 0.087, with F value respectively 45.009, 50.099, P values all below 0.01). (4) The expression levels of cadherin mRNA in 5, 10, 25, 50, and 100 ng/mL TNF-α groups were 0.70 ± 0.05, 0.63 ± 0.06, 0.60 ± 0.10, 0.45 ± 0.16, and 0.26 ± 0.14, and it was significantly lower in the latter four groups than in control group (0.83 ± 0.03, with F values all equal to 11.593, P < 0.05 or P < 0.01). The mRNA expression levels of α-SMA and collagen I in 5, 10, 25, 50, and 100 ng/mL TNF-α groups were 0.45 ± 0.10, 0.51 ± 0.16, 0.49 ± 0.12, 0.60 ± 0.09, 0.76 ± 0.03 and 0.38 ± 0.18, 0.45 ± 0.15, 0.52 ± 0.12, 0.66 ± 0.17, 0.76 ± 0.20, and they were significantly higher in the latter three groups than in control group (0.37 ± 0.14, 0.31 ± 0.12, with F value respectively 7.839, 2.898, P < 0.05 or P < 0.01).</p><p><b>CONCLUSIONS</b>TNF-α can obviously promote EnMT in a dose-dependent manner. EnMT may be another significant source of myofibroblasts that contributes to fibrotic tissue in scar formation.</p>

Effect of granulocyte-macrophage colony-stimulating factor on the mammalian target of sirolimus signaling pathway in the wound of rat / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on wound healing and mammalian target of sirolimus (rapamycin) signaling pathway in rats.</p><p><b>METHODS</b>Fifty SD rats were divided into control group (n = 25) and treatment group (n = 25) according to the random number table. All rats were inflicted with 2 cm × 2 cm full-thickness skin wound on the back. Recombinant human GM-CSF gel (10 µg/cm(2)) was applied onto the wounds in treatment group, and the actual quantity was 1 × 10(-4) µg/cm(2). Gel vehicle (10 µg/cm(2)) without any medicine was applied onto the wounds in control group. The treatment was conducted once a day up to the day of wound healing. Five rats from two groups were sacrificed on post injury day (PID) 1, 3, 5, 7, 14 respectively to observe and determine the wound healing rate. Wound tissue samples were collected at the former 4 time points to observe the histopathological changes with HE staining, and to detect the content of GM-CSF with enzyme-linked immunosorbent assay, and the expression levels of GM-CSF, CD31, and the mTOR signal pathway associated molecules P70S6K, phosphorylated (p-) P70S6K, 4E-BP1, p-4E-BP1, mTOR, p-mTOR with Western blotting. Data were processed with t test.</p><p><b>RESULTS</b>(1) Wound healing rates in control group and treatment group were close on PID 1 (t = 0.307, P > 0.05). Wound healing rate in treatment group was obviously higher than that in control group on PID 3, 5, 7, and 14 (with t values from 2.704 to 4.030, P < 0.05 or P < 0.01). (2) Compared with those in control group, more abundant granulation tissue was observed in treatment group, in which an increase in the number of microvessels and obvious proliferation of keratinized epithelial cells in wound margin were observed at each time point. (3) The content and the protein expression level of GM-CSF peaked on PID 3 in two groups, and they were (720.9 ± 0.9) pg/mL, 2.45 ± 0.10 in control group and (910.5 ± 1.3) pg/mL, 2.80 ± 0.48 in treatment group. The content of GM-CSF in treatment group was significantly higher than that in control group at each time point (with t values from 105.743 to 298.971, P values all equal to 0.000). The protein expression level of GM-CSF in treatment group was significantly higher than that in control group on PID 1, 5, and 7 (with t values from 4.070 to 5.275, P values all below 0.01). (4) The expression level of CD31 in treatment group was obviously higher than that in control group on PID 1, 3, and 7 (with t values from 7.237 to 26.401, P values all below 0.01). (5) The expression levels of mTOR and p-mTOR in treatment group were significantly higher than those in control group at each time point (with t values from 2.921 to 23.143, P < 0.05 or P < 0.01). In treatment group, the expression level of P70S6K was obviously higher than that in control group on PID 3, 5, and 7 (with t values from 2.950 to 5.275, P < 0.05 or P < 0.01), and the expression level of p-P70S6K was significantly higher than that in control group on PID 1, 3, and 7 (with t values from 3.307 to 22.793, P < 0.05 or P < 0.01). In treatment group, the expression level of 4E-BP1 was significantly lower than that in control group on PID 1, 3, and 5 (with t values from 2.449 to 6.431, P < 0.05 or P < 0.01), but the expression level of p-4E-BP1 was significantly higher than that in control group on PID 1, 3, and 7 (with t values from 5.522 to 11.613, P values all below 0.01).</p><p><b>CONCLUSIONS</b>GM-CSF can promote wound healing in rats by activating mTOR signaling pathway through phosphorylating mTOR proteins and its downstream signal molecules P70S6K and 4E-BP1.</p>

Prevalence and mortality of severe chest trauma in Three Gorges Area of China / 中国医学科学院学报

<p><b>OBJECTIVE</b>To analyze the epidemiological features of severe chest trauma (SCT) and investigate the risk factor of its mortality in the Three Gorges Area of China.</p><p><b>METHODS</b>The clinical data of 1834 SCT patients who were admitted in three hospitals in this area from January 1990 to December 2009 were retrospectively reviewed. Th epidemiological features of SCT were analyzed using a database. Stepwise logistic regression analysis was used to analyze 15 possible risk factors affecting mortality.</p><p><b>RESULTS</b>The morbidity rates of blunt trauma (68.5% vs. 74.7%,p=0.006) and sharp instrument injury (12.2% vs. 15.9%,p=0.039) showed significant differences before and after 2000. The pre-hospital time [(3.45±2.38)h vs. (2.20±4.39)h,p<0.01] and transfer rate (32.39% vs. 36.80%,p=0.01) significantly improved. The thoracic Abbreviated Injury Scale (AIS)(3.56±0.71vs. 3.43±0.58,p<0.01)score and Revised Trauma Score (RTS)(7.14±2.18 vs. 6.93±1.07,p<0.01) significantly increased. Treatment for pulmonary infection (12.63±4.79 vs. 17.16±6.41,p=0.019) and hemorrhagic shock (2.4±0.75 vs. 3.4±1.34,p=0.008 )was significantly improved. The leading cause of death was hypovolemic shock (59.41%). The independent rik factors of death among these SCT patients included: hemorrhagic shock (B=1.710,OR=1.291,p=0.001), multiple organ dysfunction syndrome (B=3.453,OR=1.028,p<0.001), pulmonary infection(B=2.396,OR=10.941,p<0.001), abdominal organ injury(B=1.542,OR=1.210,p=0.005), and thorax AIS(B=0.487,OR=1.622,p<0.001).</p><p><b>CONCLUSIONS</b>The prevalence of SCT shows an increasing trend in the Three Gorges Area in recent years, but with a decreased rate of complications and improved treatment. Age, complications, thorax AIS, and GCS are useful prognostic indicators.</p>

Association between the polymorphisms of cluster of differentiation 14 gene promoters and the susceptibility of multiple organ dysfunction syndrome after severe chest trauma / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the polymorphisms of cluster of differentiation 14(CD14)gene promoters and explore whether such polymorphisms are associated with the susceptibility to multiple organ dysfunction syndrome(MODS) in Chongqing population.</p><p><b>METHODS</b>The single nucleotide polymorphisms of the promoter region of CD14 gene at position -1145 and -159 were detected using polymerase chain reaction-restriction fragment length polymorphism method in 106 patients with severe chest trauma, among whom 47 were with MODS.</p><p><b>RESULTS</b>Trauma patients carrying G allele tended to have a higher risk of MODS than those carrying A allele at position-1145, the MODS scores in trauma patients carrying G allele were significantly higher than those carrying A allele (P=0.217 for dominant effect and P=0.037 for recessive effect), and the MODS scores in trauma patients carrying T allele were significantly higher than those carrying C allele at position -159 (P=0.048 for dominant effect and P=0.198 for recessive effect). The genotypes of CD14 gene at positions -1145 and -159 were significantly correlated with the MODS scores (P=0.043,P=0.046). Compare with single-point mutation, simultaneous two-point mutation had significantly higher risk of MODS (Pü0.01), while the difference of MODS scores showed no statistical significance (P=0.239).</p><p><b>CONCLUSION</b>The polymorphisms of CD14 gene promoters are associated with MODS after severe chest trauma in Chongqing population.</p>

Potential therapeutic application of adult stem cells in acute respiratory distress syndrome / 中华创伤杂志(英文版)

Acute respiratory distress syndrome (ARDS) remains a poor prognosis in spite of the recent development of new therapeutic strategies. Cell-based therapy with stem cells has been considered as a promising way for the treatment of vital organ damage. Putative endogenous stem cells have been shown to be located within the adult lung in the basal layer of the upper airways, within or near pulmonary neuroendocrine cell rests, at the bronchoalveolar junction, as well as within the alveolar epithelium. These stem cells are hypothesized to be the source of lung regeneration and repair. But this mechanism seems to be insufficient after lung injury. There is increasing excitement over the last few years with the suggestion that exogenous stem cells may offer new treatment options for ARDS. Exogenous stem cells have the ability to differentiate and function as both airway and lung parenchymal epithelial cells in both in vitro and increasingly in vivo experiments. However, there is great controversy concerning the repair effect of adult stem cells in lung injury. This review evaluates the advances in endogenous respiratory stem cells, and assesses the evidence for the use of stem cells in the repair of lung injury.

Bilateral regulatory action of corticotropin-releasing hormone on immune-mediated inflammation / 中华创伤杂志(英文版)

In trauma, infection and hemorrhagic shock derived stress, primary and secondary injury may result in severe derangement in the internal environment. The abnormal changes of immune-mediated inflammation interfere its pathogenesis and development directly. In recent years, various aspects of neuroendocrine responses, especially the regulatory effects of hypothalamic-pituitary-adrenal and sympathetico-adrenomedullary axes in inflammatory diseases have been the focus of research. Most importantly, corticotropin-releasing hormone (CRH) acts as a key player in the regulation of interactions between neuroendocrine and immunity both directly and indirectly. The paper summarized the recent development of CRH in the immune-mediated inflammation.

Posttraumatic stress and immune dissonance / 中华创伤杂志(英文版)

Stress or neuroendocrine response usually occurs soon after trauma, which is central to the maintenance of post-traumatic homeostasis. Immune inflammatory response has been recognized to be a key element both in the pathogenesis of post-traumatic complications and in tissue repair. Despite the existence of multiple and intricate interconnected neuroendocrine pathways, the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system have been considered to be the most important in trauma. Although the short-term and appropriate activation of these stress responses is vital to the host's adaptation, prolonged duration and exaggerative magnitude of their activity leads to deleterious effects on immune function in trauma, causing immune dissonance. The overall appropriate and controlled activation and termination of the neuroendocrine responses that mediate the necessary physiological functions involved in maintaining and restoring homeostasis in the event of trauma are of critical importance. This review will describe the effects of some important neuroendocrine responses on immune system. Present evidences indicate that the neuroendocrine and immune systems form a cohesive and integrated early host response to trauma, and identify areas for further research to fully elucidate the regulatory role of neuroendocrine system in trauma.

Relationship of myeloid differentiation-2 gene promoter polymorphisms with susceptivity of complications after severe trauma in Chinese Han population / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the polymorphisms of myeloid differentiation-2 (MD-2) gene promoters, and to explore whether such polymorphisms are associated with the susceptibility to multiple organ dysfunction syndrome (MODS) and sepsis in Chinese Han population.</p><p><b>METHODS</b>Using polymerase chain reaction-restriction fragment length polymorphism method, the authors detected the single nucleotide polymorphisms of the promoter region of MD-2 gene at position - 1625C/G in 105 severe trauma patients (42 with sepsis). The organ function was scored.</p><p><b>RESULTS</b>The frequency of CC genotype in MD-2 gene promoter region at position - 1625 was 0.5 (21/42) in septic patients and 0.7 (44/63) in non-septic patients. The frequency of CG genotype was 0.38 (16/42) in septic patients and 0.27 (17/63) in non-septic patients. The frequency of GG genotype was 0.12 (5/42) in septic patients and 0.03 (2/63) in non-septic patients. The MODS scores in trauma patients carrying G allele at position - 1625 were significantly higher than those carrying C allele (P<0.001 for dominant effect, and P>0.05 for recessive effect). Moreover, trauma patients carrying G allele appeared to have higher risk of sepsis comparing to those carrying C allele (OR 0.477, 95% CI 0.266-0.855, P<0.05). Sepsis morbidity was significantly different between subjects with C and G alleles (P<0.05 for dominant effect, P>0.05 for recessive effect).</p><p><b>CONCLUSIONS</b>The polymorphisms of the promoter region of MD-2 gene at position - 1625 C/G is correlated with MODS and sepsis after severe trauma in Chinese Han population. The people with - 1625 G allele in the promoter region of MD-2 gene may be a risk factor of severe complications.</p>

The relationship of the expression of principal pattern recognition receptor with the pulmonary injury in abdominal infection-induced sepsis / 中华外科杂志

<p><b>OBJECTIVE</b>In order to investigate the evidence of the synergistic effects of bacterial components, to observe the relationship of the expression of lipopolysaccharide (LPS) receptors [CD14, Toll-like receptor 4 (TLR4), scavenger receptor (SR)], lipoprotein receptor (TLR2) and bacterial DNA receptor (TLR9) with pulmonary injury in abdominal infection-induced sepsis.</p><p><b>METHODS</b>30 mice were used and randomly divided into cecal ligation puncture (CLP) (n = 15) and sham (n = 15) groups. The animals were respectively sacrificed 8, 12 and 24 (each point n = 5) hours following CLP and sham CLP. The lungs were removed and immediately stored in liquid nitrogen for TLRs mRNA, tumor necrosis factor (TNF) alpha and myeloperoxidase (MPO) assay. To detect the expression of CD14, TLR4, SR, TLR2 and TLR9 mRNA by reverse-transcription polymerase chain reaction, to detect the TNF-alpha content of the lung tissue by enzyme-labeled immunosorbent assay, and to assay the MPO activity of the lung tissue spectrophotometer.</p><p><b>RESULTS</b>It was found that the expression of receptors for LPS, BLP and bacterial DNA in pulmonary tissues was markedly changed in CLP-induced sepsis, showing upregulation of CD14 mRNA (1.143 +/- 0.139, t = 0.022, P < 0.05), TLR2 mRNA (0.418 +/- 0.102, t = 0.021, P < 0.05), TLR4 mRNA (0.595 +/- 0.052, t = 0.0001, P < 0.01) and TLR9 mRNA (0.743 +/- 0.178, t = 0.0023, P < 0.01) at different degrees (P < 0.05 or P < 0.01) after postinjury 8 h, among which the expression of TLR9 mRNA kept increasing. The expression of SR mRNA (8 h: 0.659 +/- 0.159; 12 h: 0.429 +/- 0.061; 24 h: 0.300 +/- 0.045; t = 0.029, P < 0.05; t = 0.001, P < 0.01; t = 0.003, P < 0.01) showed continuous down-regulation.</p><p><b>CONCLUSION</b>There was a marked correlation between the changes of pattern-recognition receptor expression and the increases of MPO and TNF-alpha levels in pulmonary tissues.</p>

Study on single nucleotide polymorphism of TLR4 in Chinese population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the single nucleotide polymorphisms(SNPs) in the regulatory and coding regions of human Toll-like receptor 4(TLR4) gene and to search for its new genetic makers.</p><p><b>METHODS</b>The 5' flank region, exons, parts of the introns, as well as 3' flank region of TLR4 gene were sequenced to identify and characterize the SNPs in Chinese population. SNP genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism for 2 highly distributed SNPs.</p><p><b>RESULTS</b>Five novel SNPs were identified through a 4.98 kb sequencing of TLR4 gene. Among them, three were in 5'flank region, two in 3'UTR. In the sample of Han population from Chongqing, the minor allele frequencies of two highly distributed SNPs were 0.266 and 0.404 respectively.</p><p><b>CONCLUSION</b>Sampling analysis in Han population of Chongqing showed that the two highly distributed SNPs of TLR4 were common in Chinese population and could be used for genetic marker of TLR4 gene.</p>

Silencing effect of recombinant plasmids PPARgamma-pSUPER-EGFP on the expression of peroxisome proliferator-activated receptor gamma / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the silencing effect of gene encoding peroxisome proliferator-activated receptor gamma (PPARgamma) on the expression of tumor necrosis factor alpha (TNFalpha) by constructing vectors for RNA interference in RAW264.7 cells.</p><p><b>METHODS</b>The pSUPER-EGFP vectors were used to transcribe functional small interfering RNA (siRNA). Four pairs of oligonucleotides (64 nt) targeting PPARgamma gene were inserted into the downstream of the H1 promotor, with their veracity confirmed by double digestion and sequencing. Western blotting and immunofluorescence assay were used to examine the silencing effect of PPARgamma gene in RAW264.7 cells. Meanwhile, the TNFalphalevel was determined by Sandwich ELISA.</p><p><b>RESULTS</b>Compared with other recombinant pSUPER-EGFP vectors (R-pSUPER.EGFP), R-pSUPER.EGFP2 induced the best silencing effect on the expression of PPARgamma in RAW264.7 cells, which played an obvious inhibitory role in down-regulating the TNFalphaexpression after the curcumin and lipopolysaccharide (LPS) stimulation.</p><p><b>CONCLUSIONS</b>PPARgamma-pSUPER-EGFP inducing a silencing effect on the expression of PPARgamma can efficiently play a negative role in controlling the inflammatory responses of RAW264.7 cells.</p>

The effects of TNF alpha and IFN gamma on the expression of pattern recognition receptors on the surface of mouse alveolar macrophages / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of tumor necrosis factor alpha (TNF alpha) and interferon gamma (IFN gamma) on the expression of pattern recognition receptors (PRRs) on the surface of mouse alveolar macrophages.</p><p><b>METHODS</b>Alveolar macrophages from mouse were cultured in DMEM supplemented with 10% (V/V) endotoxin-free calf serum. After the alveolar macrophages were stimulated with TNF alpha and IFN gamma (concentration, 20 ng/ml) for 3 h, 6 h and 12 h, the expression of PRRs, including cluster of differentiation 14 (CD14), scavenger receptor (SR), toll-like receptor 4 (TLR4), TLR2 and TLR9 mRNA and proteins were examined by RT-PCR and immunohistochemistry.</p><p><b>RESULTS</b>The expressions of CD14, TLR2 and TLR9 receptors, which were related with cellular activation, were up-regulated by the stimulation of TNF alpha and IFN gamma (P < 0.05), while SR, which was related with cellular defense action, was down-regulated (P < 0.05). Although the expression of TLR4 was up-regulated, there was no statistical significance (P > 0.05).</p><p><b>CONCLUSIONS</b>The cytokines such as TNF alpha and IFN gamma could also produce feedback regulation on the expression of PRRs at the levels of genes and proteins. Such regulation on the PRRs expression would be significant for further amplification of inflammation cascade and eventually leading to uncontrolled inflammation.</p>

The role of myeloid differentiation protein-2 in lipopolysaccharide-induced cellular activation of human endothelial cells / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the expression of myeloid differentiation protein-2 (MD-2) in the human endothelial cells and its role in lipopolysaccharide (LPS)-induced NF-kappaB activation in endothelial cells.</p><p><b>METHODS</b>In vitro cultured human umbilical vein endothelial cells (HUVEC) were employed in the study. The expression of MD-2 mRNA and protein, and the effect of LPS on the expression of its mRNA and protein were assessed with RT-PCR and Western blotting. The role of MD-2 in LPS-induced NF-kappaB activation and IL-8 production were investigated with gene transfection of mutant MD-2 cDNA (0.5, 1.0, 2.0 microg), pEF-BOS vacant vector (2.0 microg) and MD-2 plasmid (2.0 microg) into HUVEC, respectively.</p><p><b>RESULTS</b>There was MD-2 mRNA and protein expression in HUVECs before LPS stimulation, and it could be obviously upregulated by LPS in time and dose-dependent manner (MD-2 protein absorbency was 25 196 +/- 1 723 without LPS stimulation, which was obviously lower than that stimulated with 0.01 mg/L LPS (58 817 +/- 3 241, P < 0.01) for 6 hours. Transfection of mutant MD-2 cDNA could remarkably inhibit LPS-induced NF-kappaB activation and IL-8 production in endothelial cells.</p><p><b>CONCLUSION</b>MD-2 might play an important role in the LPS-induced NF-kappaB activation in HUVECs.</p>

Analysis of polymorphisms in the promoter region of interleukin-1beta by restriction fragment length polymorphism-PCR / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the frequencies of -1470, -511 and -31 single nucleotide polymorphisms (SNPs) in the promoter of IL-1beta and its haplotype constitution in Chongqing population.</p><p><b>METHODS</b>One hundred and twelve healthy Chongqing people were enrolled in this study. Polymorphisms at -1470 (G to C), -511 (T to C) and -31 (C to T) of IL-1beta were genotyped with the method of restriction fragment length polymorphism (RFLP). Haplotype frequencies were analyzed by Arlequine software.</p><p><b>RESULTS</b>Frequencies of IL-1beta -1470, -511 and -31 SNPs were 41.67%, 50% and 45.33%, respectively. Genotype frequencies of -1470 locus were 39.81%, 37.04% and 23.15% for G/G, G/C and C/C respectively. As for T-511C SNP, genotype frequencies of T/T, T/C and C/C were 29.91%, 40.18% and 29.91%, respectively. Genotyping results of C/C, C/T, and T/T of -31 locus were 35.51%, 38.32% and 26.71% respectively. Haplotype analysis found that there were mainly three haplotypes constituted by three SNPs, ie., G-T-C, C-T-C and G-C-T.</p><p><b>CONCLUSIONS</b>Polymorphisms exist in the promoter of IL-1beta in Chongqing population. Three SNPs locate in the same haplotype block.</p>