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Objective To investigate the effect of MDM2 inhibitor RG-7388 on the proliferation, cell cycle, and apoptosis of diffuse large B-lymphoma (DLBCL) cells. Methods DLBCL cell strains SUDHL2 and HBL1 were treated with 2, 4, and 8 μmol/LRG7388, respectively. Cell proliferation was detected by CCK8 and EdU methods. Apoptosis was measured by Annexin V–FITC/PI double staining and Caspase 3/7-Glo enzyme activity methods. Cell cycle was assessed by flow cytometry. Changes in the expression of cell cycle and apoptosis-related proteins were determined by Western blot. Results The IC50 of RG7388 for inhibiting SUDHL2 and HBL1 cells were 3.36 and 3.76 μmol/L, respectively, and the inhibitory effect of RG7388 was dose dependent. The proportions of G1 phase and apoptotic cells in the SUDHL2 and HBL1 cells treated with different doses of RG7388 were significantly higher than those in the control group (all P<0.05). The activity of Caspase 3/7 increased gradually with RG7388 concentration, compared with that in the control group. The expression levels of p53, p27, p21, and PARP increased, whereas the expression of Mcl-1 and Bcl-xL was down-regulated (all P<0.05). Conclusion MDM2 inhibitor RG-7388 inhibits the proliferation of DLBCL cells, triggers cell cycle arrest in the G1 phase, and induces apoptosis through the p53 pathway.
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2019 novel coronavirus (2019-nCoV) is one of the beta coronaviruses and was identified as the pathogen of the severe "coronavirus disease 2019 (COVID-19)" in 2019. China has formally included the 2019-nCoV in the statutory notification and control system for infectious diseases according to the Law of the People's Republic of China on the Prevention and Treatment of Infectious Diseases. Currently, the national defending actions on the 2019-nCoV in China is in a critical period. Burn Department is also confronted with risk of infection by the 2019-nCoV. According to the guidelines on the diagnosis and treatment of COVID-19 (6th trial edition), the latest relative literature at home and abroad, the features of the COVID-19, recommendations for the COVID-19 prevention and control issued by the National Health Commission of China, and management experience of diagnosis and treatment in the related disciplines, we put forward recommendations for the medical practices of burn treatment during the outbreak of the COVID-19 in outpatient and emergency treatment, inpatient treatment, operation and ward management, etc. We hope these recommendations could benefit the professionals of the same occupation as us and related hospital managers, improve the treatment of burn during the outbreak of the COVID-19, and avoid or reduce the risk of infection of medical staff .
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To explore the role of dentritic epidermal T lymphocytes ( DETCs) in immune rejection of skin allograft in mice and its related mechanism. Methods (1) Full-thickness skin was harvested from back of one male wild type (WT) C57BL/6 mouse. Epithelial cells were isolated for detection of the expression of DETCs and their phenotype with flow cytometer. Another male WT C57BL/6 mouse was used to harvest full-thickness skin from the back. Epidermis was isolated for observation of the morphological characteristics of DETCs with immunofluorescence technology. (2) Four male green fluorescence protein (GFP)-marked C57BL/6 mice, 7 female WT C57BL/6 mice (group WT), and 7 female ybT lymphocytes 8 gene knock-out (GK) C57BL/6 mice (group GK) were used. Full-thickness skin in the size of 1.4 cm x 1.4 cm on the back of mice in groups WT and GK were excised, and the wounds were transplanted with full-thickness skin in the size of 1.2 cm x 1.2 cm obtained from male GFP-marked C57BL/6 mice. The survival time of skin grafts was affirmed with small animal in vivo imager and naked eyes and recorded. (3) Two male WT C57BL/6 mice were used to isolate epithelial cells. Cells were inoculated into 48-well plate and divided into activation group (A) and control group (C) according to the random number table, with 4 wells in each group. Cells in group A were treated with 10 pL concanavalin A in the concentration of 2 microg/mL for 24 hours, while those in group C with PBS in the same volume as that in group A. The expression of interferon y in DETCs was detected with flow cytometer. (4) Four male GFP-marked C57BL/6 mice were used as donors. Fourteen female WT C57BL/6 mice were used as receptors and divided into interferon gamma neutralizing group (IN) and control group (C) according to the random number table, with 7 mice in each group. The skin transplantation model of C57BL/6 male to C57BL/6 female was established as in part (2). Before surgery and 72 hours after, mice in group IN were intraperitoneally injected with 200 pL interferon y neutralizing antibody in the concentration of 1 mg/mL, and those in group C with normal saline in the same volume as that in group IN. The survival time of skin grafts was observed and recorded using the methods in part (2), and the result of group IN was compared with that of group GK in part (2). The survival curve of skin grafts was processed with Log-rank ( Mantel-Cox) test. Results (1) The positive expression rate of DETCs in epithelial cells of skin in mouse was 7.27%, and they were all CD3 cells. DETCs were found to be scattered in the epidermis of skin in mouse with dendritic morphology. (2) The survival time of skin grafts of mice in group GK was 22-35 d, obviously longer than that in group WT (12-16 d, y2 = 14. 10 , P < 0.001). (3) Expression of interferon gamma was detected in 22. 70% DETCs in group A, which was obviously higher than that in group C (0.51%). (4) The survival time of skin grafts of mice in group IN was 19-24 d, which was obviously longer than that in group C (12-16 d, chi 2 = 13.60, P < 0.001) but close to that in group GK as in part (2) (chi2 = 0.06, P = 0.810). Conclusions DETCs are involved in promotion of immune rejection of skin allograft probably by secretinf interferon gamma.
Subject(s)
Animals , Female , Male , Mice , Allografts , Epidermis , Graft Survival , Allergy and Immunology , Physiology , Interferon-gamma , Allergy and Immunology , Metabolism , Lymphocytes , Mice, Inbred C57BL , Skin , Skin Transplantation , T-Lymphocytes , Allergy and ImmunologyABSTRACT
Objective To study antimicrobial resistance of clinically isolated Escherichia coli (E.coli),the preva-lence of integrons in E.coli,and relation of integron with antimicrobial resistance of E.coli.Methods E.coli isola-ted from three hospitals of Guangdong Province from 2010 to 2012 were collected,and antimicrobial susceptibility testing was performed by Kirby-Bauer method;integrons were detected by polymerase chain reaction (PCR),and gene cassette was analyzed by sequencing.Results A total of 156 E.coli isolates were collected,antimicrobial sus-ceptibility testing showed that resistance rate of E.coli to most penicillins,cephalosporins,fluoroquinolones,amin-oglycosides and sulfonamides were over 50%;the resistance rate to antimicrobials 0.05),but compared with sensitive E.coli (9.09%,2/22),the difference was statisti-cally different (P<0.01 ).There were nine types of integron-drug resistant gene cassettes in the variable regions, most of which contained aadA and dfrA.Conclusion Antimicrobial resistance of E.coli is serious;high incidence of class I integrons are widely found in E.coli,and is closely related with drug resistance of E.coli,class I integrons mainly mediated aminoglycosides,sulfonamides and beta-lactams resistance.
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Human stomach cancer cell line BGC-823 was treated by Tween 80 in combination with hyperthermia 39℃ to 43℃ for 20 to 100 minutes, respectively. The cell ultrastructure and succinate dehydrogenase (SDH) activity were studied at 0 hr, 48hr and 96hr after treatment respectively. Normal human fibroblast was used as control. The main changes of BGC-823 cells induced by hyperthermia were: dilation of endoplasmic reticulum, swelling of mitochondria, increase of fat droplets and decrease in SDH activity. After treatment at 43℃, the mitochondria showed vesicles or myelin figures and the polyribosomes tended to disaggregate. In nuclei, heterochromatin increased and the nucleolus become a dense homogeneous spot or annular ring. A few cells got necrosis. Effects of Tween 80 on BGC-823 cells were similar to that of hyperthermia. When Tween 80 combined with heating, marked synergic action was observed and the damage of membrane structure appeared earlier and more seriously. The effects of 41℃ combined with Tween 80 for 100 minutes were similar to that of 43℃ for 100 minutes alone. The critical temperature of hyperthermia for BGC-823 cells decreased to 41℃. The responses of the human fetal lung fibroblasts were slight and reversible. The results mentioned above suggested that the Tveen 80 enhanced the damage effect of hyperthermia on the tumor cells by decreasing the phase transition temperature of the tumor cells.