Aim To explore the influence of metformin(a first-line drug for type 2 diabetes) on ATP-induced inflammasome activation and the release of interleukin-1β(IL-1β) by LPS-activated peritoneal macrophages, a commonly-used inflammatory cell model.Methods Peritoneal macrophages were elicited by intraperitoneal injection of 30 g·L-1 thioglycollate into C57BL/6 mice.Inflammasome was activated and cell pyroptosis was induced by LPS plus ATP treatment, and the pyroptotic cells were calculated after propidium iodide(PI) staining.The protein levels of IL-1β and caspase-1 expressed in the cells and released from them into the supernatant were evaluated by Western blot.Immunofluorescent microscopy was recruited to detect the subcellular distribution and fluorescent intensity of the purinergic P2X7 receptor(P2X7R).Results Metformin per se did not induce pyroptosis in LPS-activated peritoneal macrophages, but it significantly and dose-dependently increased cell pyroptosis induced by ATP treatment.At protein levels, maturated IL-1β(17 ku) could not be released from the cells upon single LPS or LPS plus metformin stimulation;but after ATP was added, maturated IL-1β was released into the supernatants of the cells.Moreover, metformin dose-dependently increased the protein levels of both maturated IL-1β and active caspase-1 released by the LPS-activated peritoneal macrophages upon ATP stimulation.Conclusion Metformin intensifies the activation of inflammasome and increases the release of active caspase-1 and maturated IL-1β upon ATP stimulation in the LPS-activated peritoneal macrophages, which should promote inflammatory responses.

Aim To study the mechanism of cucurb-itacin E ( CuE )-induced autophagy in HeLa cells. Methods Improved MTT assay was adopted to meas-ure the effect of CuE on cell proliferation. Western blot was used to determine the phosphorylation levels of downstream signaling proteins of mTORC1 and the ex-pression of autophagy associated proteins. ResultsCuE inhibited the proliferation of HeLa cells in a dose-dependent manner, and the 24-h IC50 of CuE was 4. 01μmol· L-1 . CuE significantly inhibited the phospho-rylation of p70 S6 K in a time-and dose-dependent man-ner as evidenced by decreased phosphorylation levels of
the mTORC1 substrate. Meanwhile, the expression of LC3-II, a marker for autophagosome formation, was elevated by CuE treatment, and was further increased in the presence of chloroquine. Furthermore, CuE re-duced the levels of p62/SQSTM1 . These results indi-cated that CuE induced autophagy in HeLa cells. The decreased levels of phosphorylated ULK1 S757 were posi-tively correlated with autophagy induction in HeLa cells. Conclusion CuE is likely to induce autophagy through inhibiting mTORC1 activity.

BACKGROUND:It is generaly believed that the spine wil be extended, and vertebral muscle atrophy, bone loss of vertebral body, increased height and area of intervertebral disc, changes of composition of intervertebral disc wil occur in the condition of weightlessness. These are likely to be the cause of high incidence of low back pain. OBJECTIVE:To observe changes in lumbar spine bone microstructure analysis of simulated weightlessness on rhesus lumbar spine biomechanics. METHODS:Fourteen young rhesus monkeys were randomly divided into two groups: control group (n=7;free activities in the cage during the experiment), and experimental group (n=7; the use of head-down-10° on a special bed by bundle lying to simulate weightlessness). RESULTS AND CONCLUSION:(1) The results of Micro-CT examination: in the experimental group, structure model index in trabecular bone of increased. Trabecular bone changed from plate-like to the rod-like change. The intersection number of bone tissue in unit length to non-bone tissue declined. The average width of the canal between the trabecular bone increased, suggesting that there have been signs of osteoporosis in the experimental group. (2) Under an optical microscope, in the experimental group, bone hyperplasia line was disordered and irregular. Thick endplate trabecularbone became smal, shalow, and arranged substantialy perpendicular to the direction of trabecular bone and cartilage endplate. The closer the endplate surface, the smaler trabecular bone was. Compared with the control group, these smal trabecular bones were thin and curved. Bone marrow cavity was oval. The degree of the connection between the trabecular bones is poor, reflecting the structural characteristics of significant osteoporosis. (3) It is indicated that weightlessness affected the biomechanical properties of rhesus lumbar motion unit.

Objective To systematically evaluate and analyze the evidence level of randomized controlled trials (RCT) of preoperative skin preparation for emergency percutaneous coronary intervention (PCI), and to understand the current research status and evidence level of preoperative skin preparation randomized controlled trials for emergency PCI, and provide reference for skin preparation for emergency PCI. Methods PubMed, EMbase, The Cochrane Library, CINAHL, JBI, CBM, CNKI, Wanfang DATA were searched by computer from inception to March, 2018 for emergency PCI preoperative skin preparation randomized controlled trials. Two evidence panel members searched and selected articles independently and the quality was assessed in accordance with Cochrane Manual. The articles were analyzed with Review Manager 5.3, and the evidence quality was assessed with GRADE profiler 3.6.1 software. Results A total of 5 RCTs were included, of which the number of RCTs with grade A quality was 1 and the number of RCTs with grade B was 4. The results of the Meta analysis showed that there was no significant difference in the incidence of skin infections at the postoperative puncture site by conventional methods for routine removal of surgical wild hair and no removal of hair prior to emergency PCI (P＜0.05). In addition, regular removal of hair before surgery may result in prolonged preoperative preparation and may cause psychological discomfort to the patient. After the GRADE system rating, the quality of the evidence body was of a lower level. Conclusions It is more beneficial to shorten the treatment time without routine removal of all the hair at the puncture site and the surrounding patients. The evidence included is not yet certain whether the incomplete removal of hair can reduce the infection rate. In the future, more large-scale, multi-center, high-quality research should be carried out to provide more credible evidence for this study.

Objective:To investigate the promotion effect of 4,5,6,7-tetrabromobenzotriazole (TBB)on the apoptosis of human colon cancer SW480 cells,and to explore its possible mechanism.Methods:The human colon cancer SW480 cells at logarithmic growth phase were divided into control group (0 μmol·L-1 TBB)and experiment group (1,3,10,30,and 100 μmol·L-1 TBB).The viability of cells was measured by MTT assay;the apoptotic rate of the SW480 cells and the level of intracellular reactive oxygen species (ROS)were analyzed by Annexin Ⅴ-FITC/PI double staining and flow cytometry.The expression levels of anti-apoptotic proteins p-Akt and Bcl-2,and pro-apoptotic proteins Bad, pro-caspase-9 and cleaved-caspase-3 were detected by Western blotting method. Results:The MTT results showed that the viabilities of SW480 cells in experiment group were decreased in a dose-dependent manner,which were lower than that in control group (P < 0.05).The Annexin Ⅴ-FITC/PI double staining and flow cytometry results showed that the apoptotic rates of SW480 cells in experiment group (3,6,12, and 24 h)were significantly higher than that in control group (0 h)(P <0.05).The flow cytometry results showed the levels of ROS in SW480 cells after treated with TBB for 3,6,12 and 24 h were higher than that in 0 h group (P <0.05).The Western blotting results showed that the expression levels of anti-apoptotic proteins p-Akt and Bcl-2 in SW480 cells in experiment group (3,6,12,and 24 h)were decreased obviously,whereas the expression levels of the pro-apoptotic proteins Bad and cleaved-caspase-3 were increased and the expression level of pro-caspase-9 was decreased compared with those in control group (0 h) (P < 0.05 ).Conclusion: TBB could inhibit the cell proliferation and induce the apoptosis of human colon cancer SW480 cells,and its mechanism may be related to the inhibition of the activity of Akt and the promotion of the level of intracellular ROS.

This study aims to gain insight into the DNA-specific recognition mechanism of c-Myb transcription factor during the regulation of cell early differentiation and proliferation. Therefore, we chose the chicken myeloid gene, mitochondrial import protein 1 (mim-1), as a target to study the binding specificity between potential dual-Myb-binding sites. The c-Myb-binding site in mim-1 is a pseudo-palindromic sequence AACGGTT, which contains two AACNG consensuses. Simulation studies in different biological scenarios revealed that c-Myb binding with mim-1 in the forward strand (complex F) ismore stable than that inthereverse strand (complex R). The principal component analysis (PCA) dynamics trajectory analyses suggested an opening motion of the recognition helices of R2 and R3 (R2R3), resulting in the dissociation of DNA from c-Myb in complex R at 330 K, triggered by the reduced electrostatic potential on the surface of R2R3. Furthermore, the DNA confirmation and hydrogen-bond interaction analyses indicated that the major groove width of DNA increased in complex R, which affected on the hydrogen-bond formation ability between R2R3 and DNA, and directly resulted in the dissociation of DNA from R2R3. The steered molecular dynamics (SMD) simulation studies also suggested that the electrostatic potential, major groove width, and hydrogen bonds made major contribution to the DNA‍-specific recognition. In vitro trials confirmed the simulation results that c-Myb specifically bound to mim-1 in the forward strand. This study indicates that the three-dimensional (3D) structure features play an important role in the DNA-specific recognition mechanism by c-Myb besides the AACNG consensuses, which is beneficial to understanding the cell early differentiation and proliferation regulated by c-Myb, as well as the prediction of novel c-Myb-binding motifs in tumorigenesis.
Molecular Dynamics Simulation ; Consensus ; DNA ; Hydrogen