Objective To study the ability of silica nanoparticles as gene carriers for adult human epidermal keratinocytes gene transfection.Methods The silica nanoparticles-DNA conjugated with the enhanced green fluorescence protein plasmid DNA(pEGFP-N_1) was transfected into adult human epidermal keratinocytes.The expression of green fluorescence protein was investigated in transfected keratinocytes by eletromicroscope examine and the efficiency of gene transfection was revealed.Results The silica nanoparticles-DNA complexes can be effectively transfected into adult human epidermal keratinocytes and the efficiency of gene transfection was about 20%～30%.Conclusion The silica nanoparticles can be used as DNA carriers for gene transfection,and can efficiency transfect the pEGFP-N_1 into adult human epidermal keratinocytes.

Objective:To investigate the effect of SU11248 proliferation and apoptosis of multiple myeloma cell line U266 in vitro and analyze its mechanisms.Methods:Effect of SU11248 on proliferation of U266 cells was detected by MTT assay.The ability of SU11248 to induce apoptosis of U266 cells was examined by cell cycle analysis,TUNEL and DNA fragmentation.Expression of c-myc,hTERT,Bcl-2 and Bax mRNA in U266 cells was assessed by RT-PCR analysis.Results:The proliferation of U266 cells was inhibited by SU11248 in dose-and time-dependent manners (P

Objective To investigate the causes, prevention and treatment of recurrent laryngeal nerve (RLN) injury during operation in patients with thyroid cancer. Methods Clinical data of 192 patients undergone thyroidectomy operation were reviewed. Results RLN was exposed during operation in 192 patients. There were 3 cases of RLN injury, then RLN anastomosis was happened immediately during operation. It was significantiy improved in pronunciation after operation. 2 ～ 3 d after surgery, transitory hoarseness was observed in 3 patients. Unilateral RLN resection performed in 1 case with cancer involving RLN. Conclusions There were some causes of RLN injury. Exposure of RLN selectively,delicate operation and thyroid gland surgery specialist were the key point for prevention of the injury of RLN. Once RLN injury occured ,repairing should be performed as soon as possible.

Objective To construct the eukaryotic expression plasmid containing human epidermal growth factor(hEGF) gene with signal peptide(SP).Methods After two pairs of primers were designed and synthesized,the cDNA fragment of hEGF and SP genes were amplified from total RNAs. The amplified cDNA fragments were cloned into pGEM-T vector.The expression plasmids were verified by double endonuclease digestion and DNA sequence analysis. Results With RT-PCR using two pairs of primers,two bands(about 90bp and 180bp) were obtained and confirmed as signal peptide and EGF cDNA fragment with electrophoresis analysis and DNA sequencing after cloned into pGEM-T vector.The SP and EGF cDNA fragments were inserted into plasmid pcDNA3.1(+).The bands of 240bp and 5.4kb were obtained and identified as the full length of SP-EGF cDNA fragment by DNA sequence analysis.Conclusion The eukaryotic expression plasmids containing hEGF gene is successfully constructed.

Objective To investigate the clinical efficacy and mechanism of vacuum-assisted closure (VAC) in the preoperative and postoperative treatment of bedsore united with skin flap.Methods Twenty two cases with bedsore were randomly divided into experimental and control groups.In the control group,the surgery of flap was performed after the treatment of continuous negative pressure about 7-10 days and the VAC was not applied after operation.While in the experimental group,VAC was not used before operation.It was applied on flaps as soon as sutured the border of flap and decubitus ulcers and removed after 7-10 days.By comparing the general appearance of two groups,microvessel count and the detection rate of bacterial culture and other indicators,the clinical effects of two treatments were investigated and the preliminary mechanism was analyzed.Results After preoperative VAC treatment,11 cases of control group showed a little granulation tissue growth,less subcutaneous hematoma and wound effusion,increased microvessel count and negative bacterial culture.However,there were 4 cases of death cavity residual,subcutaneous hematoma and wound effusion,positive bacterial culture and another 4 cases of delayed healing with skin flap repairing bedsore.The application of VAC in experimental group showed close contact of flap with the basement,less effusion,increased microvessel count and negative bacterial culture.One case of skin flap had a small area of separation,after the dressing of skin and the flap survived.The other wounds healed by first intention.Conclusions The use of VAC to repair bedsore can reduce the number of operation,and it is beneficial to the flap survival.

Objective To confirm whether or not let-7b and miR-199a were significantly associated with malignant melanoma growth and proliferation. Methods An over -expression plasmid and an inhibitor, which targeted on let-7b and miR-199a, was constructed. B16F10 cells were divided into seven groups: control group, let-7b plasmid group, miR-199a plasmid group, empty plasmid group, let-7b inhibitor group, miR-199a inhibitor group, inhibitor control group. Foreign gene was transfected into B16F10 cells, let-7b and miR-199a expression were validated from RNA level, protein level and cell level. Results The relative let-7b or miR-199a gene expression of the let-7b plasmid group (3.8776±0.1372)and miR-199a plasmid group (2.8660±0.2821)were significantly higher than control group (P＜0.05), the relative let-7b or miR-199a gene expression of the let-7b inhibitor group (0.2057±0.0263) and miR-199a inhibitor group(0.2656±0.0253) were significantly lower than control group(P＜0.05). The cyclinD1 expression of the let-7b plasmid group(2.023±0.315) and let-7b inhibitor group (1.857±0.377) were significantly higher than control group (0.997±0.041) (P＜0.05), whereas, the Met expression of themiR-199a plasmid group (5.19±0.309) and miR-199a inhibitor group (4.87±0.044) were significantly higher than control group (2.2±0.198) (P＜0.05). The let-7b plasmid group and miR-199a plasmid group B16F10 cell growth rate were slower than control group, especially on the third day after transfection, the growth rate gradually dropped to the lowest value (P＜0.05). In addition, the apoptosis rates of the let-7b plasmid group and miR-199a plasmid group reach to (11.8±1.19)% and (11.3±1.59)%,which were significantly higher than control group (P＜0.05). Conclusions let-7b and miR-199a may be a negative regulator on the B16F10 cell growth and proliferation.

Objective To study the influence of let-7b on cell proliferation and aerobic glycolysis of human melanoma cell A375.Methods Transfect A375 cell line with hsa-let-7b oligonucleotide or antisense.Glucose and lactate in medium were determined by spectrophotometry at 24 h and 48 h time point after transfection.The cell proliferation was determined by methylthiazol tetrazolium (MTT) assay.Results Over expression of let-7b in melanoma cell reduced cell proliferation notably,compared to the other groups by MTT(P ＜0.05).However,the glucose consumption and lactate production differences were not observed during 24 h or 48 h ( P ＞ 0.05 ),the blank control group transformed about 57％ and 43％ glucose to lactate during 24 h and 48 h.Conclusions Melanoma cell line A375 has notably aerobic glycolysis hallmark,let-7b could inhibit proliferation of melanoma cell line A375,but it may has no influence on glucose metabolism.

MicroRNAs have been identified as a new class of regulatory molecules that affect many biological functions by interferring the target gene expressions. Latest studies demonstrate that microRNAs can influence many pivotal bio-processes and deeply involve in the metabolism of glucose, lipid and amino acid and biological oxidation. For glucose metabolism, microRNAs are related to insulin secretion, insulin sensitivity, glucose uptake, glycolysis, oxidation and mitochondrial function. For lipid matebolism, microRNAs can regulate the target genes related to lipid biosynthesis, catabolism and transportation. MicroRNAs can influence glutamine catabolism.
Animals ; Glucose ; metabolism ; Glutamine ; metabolism ; Humans ; Insulin ; metabolism ; Insulin Secretion ; Lipid Metabolism ; physiology ; Metabolism ; physiology ; MicroRNAs ; physiology

Cases of 2019-nCoV nucleic acid and antibody (IgM and IgG total antibody) after discharge from a hospital in Chongqing were continuously monitored. It was found that 5 cases of "re-positive" phenomenon, 5 cases of antibody were positive, and there was a trend of increasing with time. "Re-Positive" may be related to the following three factors. Children with asymptomatic infection had a long time of fecal detoxification.There were two consecutive nucleic acid tests "false negative" caused by various reasons.The virus clearance in patients was not complete, and the discharge standard was not conservative enough. The analysis of the causes of "Re-Positive" patients and the discussion of its infection will help us reveal more characteristics of this virus, and to provide a new basis for the discharge standard in the constantly updated diagnosis and treatment programme.

Objective: To investigate the distribution and resistance of pathogens isolated from blood cultures in patients with hematological malignancies after chemotherapy in Union Hospital of Fujian Medical University so as to understand the real situation of blood stream infection (BSI) and provide the basis for rational use of antibiotics in clinic. Methods: The data of 657 strains isolated from blood culture specimens of patients with hematological malignancies from January 2013 to December 2016 were collected analyzed. Results: A total of 657 cases of blood culture positive bacterial strains were included in the study, involving 410 cases (62.4%) with single Gram-negative bacteria (G^- bacteria) , 163 cases (24.8%) with single Gram-positive bacteria (G⁺ bacteria) , 50 cases (7.6%) with single fungi. The most common 5 isolates in blood culture were Klebsiella pneumoniae (17.5%) , Escherichia coli (17.2%) , Coagulase negative staphylococci (CNS) (14.9%) , Pseudomonas aeruginosa (14.2%) and Staphylococcus aureus (3.5%) . The extended-spectrum beta-lactamase (ESBL) production rates of Klebsiella pneumoniae and Escherichia coli were 25.2% and 55.8%, respectively. ESBL producing strains were almost more resistant than non-ESBL producing strains. The resistance rates of Enterobacteriaceae to carbapenems, piperacillin/tazobactam and tigecycline were lower than 14.0%. The resistance rates of Pseudomonas aeruginosa to a variety of drugs were lower than 12.0%. Tigecycline-resistant Acinetobacter baumannii bacteria were not detected, and the resistance rates of Acinetobacter baumannii to cefixime and cefotaxime were 7.1%. Methicillin-resistant strains in CNS (MRCNS) and in Staphylococcus aureus (MRSA) accounted for 84.7% and 43.5%, respectively. Vancomycin, linezolid and tigecycline-resistant G⁺ bacteria were not detected. Conclusion The pathogens isolated from blood culture were widely distributed. Most of them were G^- bacteria, and the resistance to antibiotics was quite common. Furhermore, vancomycin, linezolid and tigecycline can be chosen empirically to treat patiens who ar suspected to have G⁺ bacterial BSI.