Objective The recombinant fluorescent eukaryotic expressing vector containing hTERT cDNA was transfected into human embryonic fibroblasts (hEFs) to explore the effects of exogenous hTERT on the type I and III collagens expression in hEFs. Methods p IRES2-EGFP-hTERT plasmid and pIRES2-EGFP plasmids were transfected into primary hEFs respectively by Lipofectin reagent. Expression of type I and III collagen was determined by Western blotting and the content of type I and III collagens in the cellular medium at 3 days after transfection were examined by radio-immunoassay. Results The expression levels of type I and III collagens in hTERT gene transfected hEFs(hEF-hTERT) were obviously higher than those in untransfected hEFs and vacant vector transfected hEFs(hEF-EGFP). The content of type I and III collagens in the cellular medium in hEF-hTERT cells at 3 days after transfection was also higher than that in untransfected hEFs and hEF-EGFP cells. Conclusions The synthesis ability of type I and III collagens in hEFs could be promoted by exogenous hTERT gene transfection.

Objective To obtain the protein interacting with inhibitor of differentiation1′(Id1′). Methods The recombinant bait plasmid pHybLex/Zeo Id1′ was constructed and transformed into yeast strain EGY48/ pSH18 34 to test pHybLex/Zeo Id1′ for non specific activation. Adult human lung cDNA libraries were screened to obtain true positive library plasmid. The true positive library clone was obtained by sequencing and basic local alignment sequence tool (BLAST). Results The recombinant bait vector, named as pHybLex/Zeo Id1′, was confirmed by sequencing. pHybLex/Zeo Id1′ was transformed into yeast strain EGY48/pSH18 34 and the transformants had no autonomously activated reporter genes. One true positive clone, obtained by screening of the adult human lung cDNA libraries, was confirmed to be Fyn by sequencing and BLAST. Conclusion Id1′ can interact with Fyn.

Surgical robots, as a new means for surgeons, have been gradually applied in orthopedics. Initially, the development of orthopedic robots was stagnant for a long time because of limited techniques available, clumsy equipment, high costs, and low market demands. The recent decade has witnessed rapid growth of artificial intelligence in all walks of life, increasing investment in research and development, reducing manufacture costs and expanding demands for precise and individualized medical treatment so that a wide variety of novel and ingenious robotic systems have been proposed, prototyped, and commercialized in most of the major procedures in orthopedic surgery, including knee and hip replacements, cruciate ligaments surgery, spine surgery, corrective osteotomy, bone tumor surgery, and trauma surgery. This review depicts the history of development and future prospects in application of surgical robots in the field of orthopedics.

OBJECTIVETo investigate the significance of the expression pattern and its signal modulating mechanism of endothelial ICAM-1 induced by LPS.

METHODS(1) The expression pattern of the ICAM-1 was observed at mRNA level in cultured human umbilical vascular endothelial cells (HUVECs) strain ECV-304 after being stimulated by different LPS concentrations at different time points. (2) The modulating effects of different signal pathways on the ICAM-1 expression of the HUVECs were observed at mRNA and protein levels under the stimulation of LPS after the cells were primed by signal pathway blocking agents for 30 mins.

RESULTS(1) The ICAM-1 mRNA expression could be induced by LPS (100 pg/ml) for 6 hours, and the expression was enhanced along with the increase of LPS concentration. The expression peaked when LPS was at concentrations of 100 approximately 1 000 ng/ml. Temporally, the mRNA expression reached the top level at 6 approximately 8 hours and remained high 12 hours after the stimulation. (2) The expressions of ICAM-1 mRNA and protein could be significantly inhibited by PSI, the NF-kappaB inhibitor. Moreover, the expression of ICAM-1 could all be partially inhibited at mRNA and protein levels by PD98059, the ERK1/2MAPK inhibitor, as well as SB203580, the p38MAPK inhibitor.

CONCLUSIONThe ICAM-1 mRNA expression of HUVECs could be induced by LPS in both dose and time dependent manner. NF-kappaB might be the major signal pathway of modulating ICAM-1 expression, and p38 and ERK1/2 could possibly be signal pathways of minor importance.

Cells, Cultured ; Dose-Response Relationship, Drug ; Gene Expression Regulation ; drug effects ; Humans ; Intercellular Adhesion Molecule-1 ; genetics ; Lipopolysaccharides ; toxicity ; Mitogen-Activated Protein Kinases ; physiology ; NF-kappa B ; physiology ; Signal Transduction ; Time Factors

Objective:To investigate the inhibitory effect of RMT1-10-induced tolerogenic dendritic cells (Tol-DCs) in vitro on high-risk corneal allograft rejection in mice and its mechanism. Methods:One hundred SPF male BALB/c mice and fifty SPF male C57BL/6 mice were selected.Bone marrow-derived immature dendritic cells (imDCs) obtained from C57BL/6 mice were divided into imDCs group, mature dentritic cells (mDCs) group, RMT1-10 group, and IgG isotype control group.The imDCs in the four groups were cultured with no intervention, lipopolysaccharide, RMT1-10 and lipopolysaccharide, or IgG isotype antibody and lipopolysaccharide for 7 days according to grouping.The expression levels of different phenotypes of DCs including CD11c, CD80, CD86, major histocompatibility complex (MHC)-Ⅱ, T cell immunoglobulin and mucin domain containing molecule (Tim)-4 and CD103 in the four groups were detected by flow cytometry.The concentrations of interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) in the DCs supernatants were determined by enzyme-linked immunosorbent assay.A mixed lymphocyte culture system was established, and the stimulation index (SI) of CD4 + T cell proliferation stimulated with DCs was detected by cell counting kit 8 method.Corneal neovascularization was induced by corneal stromal suture in BALB/c mice, and the 80 mice with neovascularization in 4 quadrants growing into the middle and peripheral cornea were used as recipients.The recipient mice were randomized into imDCs group, mDCs group, RMT1-10 group, and IgG isotype control group using the random number table method, with 20 mice in each group.An injection of corresponding DCs (1×10 6 cells/100 μl) was administered to the recipient mice via the tail vein according to grouping.At 7 days following the injection, C57BL/6 mice were used as donors and penetrating keratoplasty was performed.Within one month after the operation, signs of corneal grafts rejection, including opacity, edema and neovascularization, were observed by slit lamp biomicroscopy and scored every day.At 21 days after the operation, 5 recipients selected from each group were subcutaneously injected with naive C57BL/6 splenocytes (1×10 6 cells/100 μl) behind the ear.The delayed type hypersensitivity (DTH) was evaluated by ear swelling at 24 hours after the subcutaneous injection.The use and care of experimental animals complied with the Regulations on the Management of Experimental Animals promulgated by the State Science and Technology Commission.This study protocol was approved by an Ethics Committee of the Affiliated Hospital of Chengde Medical University (No.CYFYLL2020055). Results:Compared with mDCs group, the expressions of CD80, CD86 and MHC-Ⅱ, and the percentage of Tim-4-positive cells in CD11c-positive cells were significantly decreased in RMT1-10 group, showing statistically significant differences (all at P<0.001). The percentage of Tim-4-positive cells were significantly decreased in RMT1-10 group than imDCs group, and the percentage of CD103-positive cells in RMT1-10 group was significantly higher than imDCs group, mDCs group and IgG isotype control group (all at P<0.001). The concentrations of IL-10 and TGF-β in the cell culture supernatant of RMT1-10 group were significantly higher than those of the other three groups, with statistically significant differences (all at P<0.001). There were statistically significant differences in the SI of CD4 + T cell proliferation simulated by DCs ( Fgroup=1 833.00, P<0.001; Fratio=230.40, P<0.001; Finteraction=3.06, P=0.01). The SI of DCs/CD4 + T cells ratio at 1∶5, 1∶10, 1∶20 and 1∶40 were all significantly lower in imDCs group than mDCs group, and were all significantly lower in RMT1-10 group than imDCs group (all at P<0.05). There was a statistically significant difference in corneal graft survival curve among various groups ( χ2=77.69, P<0.001). The survival rate of RMT1-10 group was significantly higher than that of imDCs group ( χ2=9.74, P=0.002), and the survival rate of imDCs group was significantly higher than that of mDCs group ( χ2=31.02, P<0.001). The ear swelling of recipient mice of positive control group, mDCs group, IgG isotype control group, imDCs group and RMT1-10 group was (503.6±17.2), (475.7±17.6), (456.2±18.8), (225.2±39.4), (118.1±12.6), and (106.4±7.4) μm, with a statistically significant difference among them ( F=377.10, P<0.001). The mice ear swelling was more serious in positive control group than mDCs group, more serious in IgG isotype control group than imDCs group, and more serious in imDCs group than RMT1-10 group (all at P<0.05). Conclusions:RMT1-10 can inhibit the rejection of high-risk corneal transplantation in mice, the mechanism of which may be attributed to inducing imDCs to transform into Tol-DCs in vitro and up-regulating the expression of TGF-β and IL-10, which promotes antigen-specific immune tolerance after adoptive transfer, thereby indirectly prolongs the survival of corneal grafts.

Objective:To develop a grading system for necrosis of pedicled flaps in reconstruction of foot and ankle, and to verify its effectiveness and repeatability.Methods:A retrospective observational study was conducted. A total of 40 necroses of foot and ankle pedicled flaps were selected by 2 senior surgeons based on the flap surgery performed by the same surgical group in Department of Orthopaedic Surgery, the 920 Hospital of Joint Logistic Support Force of PLA from January 2010 to January 2022. A grading system for pedicled flap necrosis was proposed by a working group and the 40 necrotic flaps were graded. The coincidence rate was calculated to evaluate the effectiveness of the grading system through correlation studies between grading and clinical treatment. One photo of a typical postoperative necrotic flap was collected from each of the 40 flaps. Then 5 extramural surgeons were asked to grade the necroses shown on the photos according to the proposed grading system. Moreover, weighted Kappa analysis was performed on the results of proposed grading system and also on the standard grading currently in use, to evaluate the repeatability of the proposed grading system. Evaluated data were expressed by Mean±SD, and the coincidence rate was expressed by percentage. The reproducibility was studied by weighted Kappa analysis.Results:Of the 40 necrotic flaps, 7 flaps were classified in Grade I, 16 in Grade Ⅱ, 12 in Grade Ⅲ and 5 in Grade IV. In comparison with the actual treatment methods, the overall coincidence rate of the grading system was 92.5%. It indicated that the proposed grading system could effectively guide the selection of a treatment procedure. The average weighted Kappa coefficient of surgeons was at 0.628 with a 95% confidence interval (95%CI) between 0.460-0.796, which was strongly consistent with the standard of the grading system currently in use.Conclusion:The grading system for necrosis of pedicled flap in reconstruction of foot and ankle proposed in this study is simple and clear. It is able to effectively guide the treatment of flap necrosis. The preliminary validation shows that the classification system has good repeatability.