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Recently, the need for antibacterial dressings has amplified because of the increase of traumatic injuries. However, there is still a lack of ideal, natural antibacterial dressings that show an efficient antibacterial property with no toxicity. Polyimide (PI) used as an implantable and flexible material has been recently reported as a mixture of particles showing more desirable antibacterial properties. However, we have identified a novel type of natural polyimide (PI) fiber that revealed antibacterial properties by itself for the first time. The PI fiber material is mainly composed of C, N, and O, and contains a small amount of Ca and Cl; the characteristic peaks of polyimide appear at 1774 cm -1 , 1713 cm -1 , 1370 cm -1 , 1087 cm -1 , and 722 cm -1 . PI fibers displayed significant antibacterial activities against Escherichia coli (as a Gram-negative bacteria model) and methicillin-resistant Staphylococcus aureus (MRSA, as a Gram-positive bacteria model) according to the time-kill kinetics in vitro , and PI fibers damaged both bacterial cell walls directly. PI fibers efficiently ameliorated a local infection in vivo , inhibited the bacterial burden, decreased infiltrating macrophages, and accelerated wound healing in an E. coli - or MRSA-infected wound model. In conclusion, PI fibers used in the present study may act as potent antibacterial dressings protecting from MRSA or E. coli infections and as promising candidates for antimicrobial materials for trauma and surgical applications., Competing Interests: The authors declare that they have no competing interests., (This journal is © The Royal Society of Chemistry.)

Objective: To determine the association of post-traumatic acute respiratory distress syndrome (ARDS) on poor prognosis, and provide a theoretical basis for the treatment of patients with post-traumatic ARDS in clinical practice., Methods: This was a retrospective study including trauma victims in the intensive care unit (ICU) of Daping Hospital. The patients were classified as having ARDS or non-ARDS, according to the Berlin definition. Subsequently, these patients were divided into subgroups, according to age, gender and injury site. The relationship between ARDS and prognosis was analyzed, including mechanical ventilation days, length of ICU stay, length of hospital stay, infection, sepsis, multiple organ dysfunction syndrome (MODS) and death., Results: There were 507 trauma patients, out of which 287 (56.61%) cases were with ARDS. The duration of mechanical ventilation, ICU stay and hospital stay in the ARDS group was significantly longer than that in the non-ARDS group (5 days vs 3 days, 10 days vs 4 days, 30 days vs 27 days, respectively). In addition, ARDS was associated with an increased risk of nfection (p<0.05; OR=4.17; 95%CI=2.72-6.41), sepsis (p<0.05; OR=3.45; 95%CI=2.28-5.22), and MODS (p<0.05; OR=2.82; 95% CI=1.67-4.72), but had no significant association with mortality (p>0.05). Similar results were found in the subgroup analyses., Conclusion: In conclusion, the prognosis of the patients with post-traumatic ARDS was worse; however, ARDS had little effect on death.

Aberrant epigenetic regulation is critically involved in the pathogenesis of nasopharyngeal carcinoma (NPC), where abnormal histone methylation can be found in polycomb repressive complex-2 (PRC2) related cancer gene loci. This study investigated some novel combinational strategies against NPC in vitro using PRC2-targeting agents as a backbone. PRC2 subunit proteins were overexpressed in over 70% of NPC tumors and enhancer of zeste homolog-2 (EZH2) expression correlated with more advanced T-stage. Basal expression of EZH2 and embryonic ectoderm development (EED) was higher in Epstein-Bar virus (EBV) + NPC cells than EBV - cells. Treatment with an EED inhibitor (EED226) led to reduced levels of H3K27me3 with minimal inhibitory effect on NPC cell growth. The combination of an EZH2 inhibitor (EPZ-6438) and trichostatin-A (TSA) yielded the highest synergy score (12.64) in NPC cells in vitro than combinations using EED226 and agents like chemotherapy and azacitadine. Global gene expression analysis showed that EED226 predominantly affects the expression of major histocompatibility complex (MHC) class I genes and cell cycle-related genes in NPC cells. Furthermore, treatment with EED226 resulted in increased MHC-I proteins in vitro . Based on the prediction of an artificial neural network, a synergistic inhibitory effect on growth was found by combining EED226 with cyclin dependent kinase (CDK) 4/6 inhibitor (LEE011) in NPC cells. In summary, this study found that PRC2-targeting agents could exert synergistic effect on growth inhibition when combined with TSA or LEE011 in NPC cells. Since MHC-I genes alterations are found in a third of NPC tumors, the effect of EED226 on MHC-I genes expression on response to immunotherapy in NPC warrants further investigations., Competing Interests: None., (AJCR Copyright © 2020.)

Objective: To investigate the impact of additional gastrectomy after endoscopic submucosal dissection(ESD) on the prognosis of early gastric cancer., Methods: Clinical data of 107 early gastric cancer patients undergoing additional gastrectomy after ESD (research group, n=44) or radical surgery (control group, n=63) from January 2008 to December 2014 in Zhongshan Hospital were retrospectively analyzed. The reasons for additional gastrectomy after ESD included positive resection margin (n=10), lymphovascular invasion (n=5), well-differentiated mucosal tumor with a diameter >3 cm (n=10), poor-differentiated mucosal tumor with a diameter >2 cm (n=4), submucosal tumor(sm1) with a diameter >3 cm (n=10), and submucosal tumor(sm2) (n=9). Operation time, length of stay, lymph node metastasis, tumor recurrence and disease-free survival rate were compared between two groups., Results: Baseline data of two groups were not significantly different (all P>0.05). After evaluation, absolute and relative indications were identified in 19 cases (43.2%) and 25 cases (56.8%) of research group, and in 28 cases (44.4%) and 35 cases(55.6%) of control group without significant difference (P=0.897). Lymph node metastasis occurred in 6 patients (4.5%) after surgery in research group and 6.3% in control group (P=0.690). Operation time was (218.5±74.3) minutes in research group and (219.8±81.8) minutes in control group (P=0.932). Length of stay was (10.0±12.3) days in research group and (10.8±9.9) days in control group (P=0.687). Follow-up time was (35.5±15.0) months in research group and (29.5±18.1) months in control group (P=0.072). Tumor recurrence rate was 4.5% in research group and 9.5% in control group (χ(2)=0.928, P=0.229). Mortality was 4.5% in research group and 7.9% in control group (χ(2)=0.487, P=0.485). Besides, no significant differences of operation mode (P=0.164), lymphatic clearance mode (P=0.330), number of harvested lymph node (P=0.467), morbidity of postoperative infection or fever (P=0.923) were found. Three-year tumor-free survival rate was 95.5% and 89.2% in research and control group respectively without significant differences (P=0.571)., Conclusion: Additional gastrectomy after endoscopic submucosal dissection has no negative influence on the prognosis of patients with early gastric cancer, whose efficacy is similar to simple radical gastrectomy.

Objective: To study the anti-inflammatory effects of idazoxan (IDA) on endotoxin lipopolysaccharide (LPS) challenged mice in vivo and activated macrophages in vitro, and explore its potential molecular mechanisms., Methods: To do the experiments in vivo,30 adult male C57BL/6 mice were randomly divided into control group, model group, and low,medium and high doses IDA groups (IDA-L,IDA-M, and IDA-H groups),n =6 in each group. The inflammatory model was reproduced by intraperitoneal injection of LPS 10 mg/kg, and the control group was injected with the same amount of normal saline. The IDA groups received LPS (10 mg/kg) and IDA 0.3,1.0 and 3.0 mg/kg, respectively. The blood samples of mice in each group were collected at 6 hours after the reproduction of the model .For the in vitro experiments, primary peritoneal macrophages were collected from 20 adult male C57BL/6 mouse cells and they were divided into control group, LPS group (10 mg/L) and LPS+IDA-L,IDA-M,IDA-H groups (10 mg/L LPS + 5,25,100 μmol/L IDA, respectively).Cell culture supernatants were collected at 24 hours after the reproduction of the model. Detection methods: enzyme linked immunosorbent assay (ELISA) was used to determine the levels of serum tumor necrosis factor-α (TNF-α),interleukin-6 (IL-6),monocyte chemotactic protein-1 (MCP-1) and nitric oxide (NO).Western Blot was used to determine the effect of IDA on the expression levels of nuclear factor-κB (NF-κB) in macrophages., Results: ① For the in vivo experiment, the serum levels of TNF-α and IL-6 were significantly elevated in the model group as compared with those in the control group [TNF-o (ng/L):403.96 ± 40.98 vs.17.50 ± 8.68;IL-6 (ng/L):61 400.31 ± 7 826.61 vs.2 436.30 ± 448.89;both P ＜ 0.01].IDA treatment could inhibit the elevation of inflammatory cytokines in a dose-dependent manner, with the most significant decrease in LPS+IDA-H group [TNF-α (ng/L):170.09 ± 28.53 vs.403.96 ± 40.98,IL-6 (ng/L):16 570.81 ± 1 083.65 vs.61 400.31± 7 826.61;both P ＜ 0.01].② For the in vitro experiment, the levels of TNF-α,IL-6,MCP-1,and NO secreted by LPS-stimulated macrophages were distinctly higher in the LPS group than those in the control group [TNF-α (ng/L):7 259.14 ± 320.70 vs.28.50±27.08,IL-6 (ng/L):14809.60±5852.73 vs.1 113.47±465.53,MCP-1 (ng/L):20847.37± 1 788.33 vs.447.37± 395.69,NO (μmol/L):1 900.00 ± 144.31 vs.603.03 ± 102.18;all P ＜ 0.01]. However, IDA intervention could lower the secretion of TNF-α,IL-6,MCP-1 and NO in a dose-dependent manner, with the most notable decrease in the LPS+IDA-H group [TNF-α (ng/L):784.40±281.90 vs.7259.14±320.70,IL-6 (ng/L):1 802.96± 1 534.18 vs.14 809.60± 5 852.73,MCP-1 (ng/L):2005.26± 1 534.28 vs.20847.37 ± 1 788.33,NO (μ mol/L):654.54± 150.21 vs.1 900.00 ± 144.31;all P ＜ 0.05].In addition, IDA at the concentration of 100 μmol/L could promote the translocation of NF-κBp65 in macrophages into the nucleus 15 minutes early and lead to increased NF-κBp65 expression (gray value:18.70 ± 2.29 vs.1.09 ± 0.36,P ＜ 0.05),hut significantly reduce the expression levels of NF-κBp50 in the nucleus at 45 minutes after treatment (gray value:1.99 ± 0.14 vs.2.94 ± 0.54,P ＜ 0.05)., Conclusions: IDA could significantly reduce inflammation of mice challenged with LPS and inhibit inflammatory cytokines and mediators secreted by macrophage in a dose-dependent manner. High concentration of IDA (100 μmol/L) exhibited the greatest anti-inflammatory effects. The anti-inflammatory effect of IDA may be worked through NF-κB signaling pathway.

Objective: To determine the feasibility and efficacy of endoscopic submucosal dissection(ESD) in treating early gastric cancer(EGC) and precancerous lesions in the remnant stomach of patients after gastrectomy., Methods: Clinical data of 36 patients with EGC and precancerous lesions in remnant stomach undergoing ESD in Endoscopy Center of Zhongshan Hospital from January 2008 to December 2013 were retrospectively analyzed. Operative, postoperative conditions and long-term follow-up of these patients were evaluated., Results: Both the success rate and the complete resection rate were 100%. The average maximum diameter of the tumor was 1.5(range 0.6-4.5) cm. During the ESD process, two bleeding cases were treated successfully by endoscopic hemostasis. The average operation time was 40(10-80) min. The delayed hemorrhage developed in 2 cases within 1-3 days after operation, and were also treated successfully by endoscopic hemostasis. There was no perforation or delayed perforation. No emergency surgery was required for the complication. Twelve cases were diagnosed as mild-moderate dysplasia, 7 cases as high grade intraepithelial neoplasia, 16 cases as hyperplastic polyps, and 1 case as signet ring cell carcinoma with T1 stage, who underwent operation for resecting gastric stump and lymph node dissection 7 days after ESD without subsequent follow-up. The curative resection rate was 92.7%(35/36). The median follow-up of the remaining 35 patients was 36(6-78) months without discomfort and recurrence under gastroscopy., Conclusion: ESD is safe and effective for EGC and precancerous lesions in the remnant stomach.