Objective To investigate the transfection of human papilloma virus types 16E6 gene on the proliferation and apoptosis of cervical carcinoma cell line C33A. MethodsPlasmid pcDNA3-HPV16E6 was stably transfected into C33A cells by liposome, and the expression of HPV16E6 mRNA and protein in the transfected cells, the cells transfected with blank vector and the cells without transfection were identified by RT-PCR and Western blot analysis. The growth, proliferation and cell cycles of the 3 kinds of C33A cells were by cell growth curve plotting and flow cytometry analysis. ResultsC33A cells were transfected stably by liposome with plasmid pcDNA3-HPV16E6 (C33A-E6 cells)and plasmid pcDNA3 (C33A-P cells). The growth of C33A-E6 cells was more rapid than those of C33A-P and C33A cells (P0.05). ConclusionHPV16E6 is involved in the cell cycle probably through some signal pathways, and promotes cell division and proliferation of C33A cells.

Objective To study the change and the correlation of serum soluble vascular cell adhesion molecuh-1(sVCAM-1)level with diabetic retinopathy in type 2 diabetic patients.Methods 60 type 2 diabetic patients were selected for the study through the examination of ophthalmoscope and/or fundus fluorescence angiography by ophthalmologist.Diabetic patients were divided into three main groups:No signs of diabetic retinopathy(NDR)(n=20);Background DR(BDR)(n=20)Proliferative DR(PDR)(n=20).Healthy individuals matching sex and age of the patients were used as controls(n=20);Serum sVCAM-1 level was measured by ELISA,compared in diabetes without DR,with BDR,with PDR.These levels were compared with those of 20 controls.Results The serum level of sVCAM-1 in the DM patients with PDR or BDR and those without DR were significantly higher than those in healthy controls(all P＜0.001);Serum level of sVCAM-1 in PDR groups were higherthan those in DM patients with BDR or patients without DR(all P＜0.001);There was no difference between the patients with BDR and those without DR (P＞0.05).(4)In the DM patients,there was a positive correlation between serum sVCAM-1 and the course of diseases(r=0.338,P＜0.05),but no relationship with HbA1C,FBG,CHO,TG,LDL and INS.Conclusion Increased serum level of sVCAM-1 in different stage of DR patients suggested that they hagbe play an important role in the development of DR,and may assess the severity of diabetic retinopathy.The measuremem of serum sVCAM-1 levels in type 2 diabetic patients could be clinically useful for early diagnosis or treatment of diabetic retinopathy.

Objective To investigate the therapeutic effects of endoscopy for palliative treatment of advanced pancreatic cancer. Methods A typical case of un-resectable advanced pancreatic cancer was reviewed, who underwent obstruction of upper gastrointestinal tract, obstructive jaundice and alimentary tract hemorrhage subsequently. The patient received multiple placement of intestinal tract stents, common bile duct stents and hemostatic treatment endoscopically. Because of the obstruction of upper gastrointestinal tract, jejunalostomy and retrograde endoscopy through the orificium fistulae were performed to place bile duct stents. Results The patient survived for 10 months with good life quality after diagnosis, obstruction of upper gastrointestinal tract, obstructive jaundice and alimentary tract hemorrhage were cured and didn't recur till death.Conclusion Therapeutic endoscopy, safe and effective, is the first choice for advanced pancreatic cancer complicated with obstruction of digestive tract (including gastrointestinal tract, bile duct and pancreatic duct).

Objective:To investigate the regulatory role of miR-17-5p on B7-H3 and its immunomodulatory role in the develop-ment of colorectal cancer.Methods:Twenty-five pairs of human colorectal cancer tissues and adjacent normal tissues were collected,and the expression levels of miR-17-5p,B7-H3 and PD-L1 were analyzed by real-time fluorescence quantitative PCR,protein immuno-blotting and immunohistochemical assays.Human colorectal cancer HCT-116 cells were divided into four groups:miR-NC group,miR-17-5p mimic group,si-NC group and si-B7-H3 group.The growth,invasive ability and apoptosis rate of HCT-116 cells were ana-lyzed by cell colony formation assay,Transwell assay and flow cytometry.The regulatory effect of miR-17-5p on B7-H3 was analyzed by luciferase reporter gene assay.The levels of IL-2,IL-4,IL-6,IL-10,IFN-γ and TNF-α cytokines in the cell culture medium were analyzed by ELISA.Results:Compared with paracancerous tissues,miR-17-5p expression was decreased and B7-H3 expression was increased in colorectal cancer tissues.miR-17-5p mimic and si-B7-H3 were able to reduce the number of HCT-116 cell colony forma-tion and invasion,promote HCT-116 cell apoptosis,and decrease the levels of IL-2,IL-4,IL-6,IL-10,IFN-γ and TNF-α cytokines in culture medium.In addition,miR-17-5p mimic and si B7-H3 were able to inhibit PD-L1 expression in HCT-116 cells.Conclusion:miR-17-5p can targeting inhibit B7-H3 expression,affect the immunomodulatory role in colorectal cancer development,and inhibit metastasis and promote apoptosis of colorectal cancer cells.

The objective of this study was to investigate the genetic basis of high level aminoglycoside resistance in Acinetobacter baumannii clinical isolates from Beijing, China. 173 A. baumannii clinical isolates from hospitals in Beijing from 2006 to 2009 were first subjected to high level aminoglycoside resistance (HLAR, MIC to gentamicin and amikacin>512 µg/mL) phenotype selection by broth microdilution method. The strains were then subjected to genetic basis analysis by PCR detection of the aminoglycoside modifying enzyme genes (aac(3)-I, aac(3)-IIc, aac(6')-Ib, aac(6')-II, aph(4)-Ia, aph(3')-I, aph(3')-IIb, aph(3')-IIIa, aph(3')-VIa, aph(2″)-Ib, aph(2″)-Ic, aph(2″)-Id, ant(2″)-Ia, ant(3″)-I and ant(4')-Ia) and the 16S rRNA methylase genes (armA, rmtB and rmtC). Correlation analysis between the presence of aminoglycoside resistance gene and HLAR phenotype were performed by SPSS. Totally 102 (58.96%) HLAR isolates were selected. The HLAR rates for year 2006, 2007, 2008 and 2009 were 52.63%, 65.22%, 51.11% and 70.83%, respectively. Five modifying enzyme genes (aac(3)-I, detection rate of 65.69%; aac(6')-Ib, detection rate of 45.10%; aph(3')-I, detection rate of 47.06%; aph(3')-IIb, detection rate of 0.98%; ant(3″)-I, detection rate of 95.10%) and one methylase gene (armA, detection rate of 98.04%) were detected in the 102 A. baumannii with aac(3)-I+aac(6')-Ib+ant(3″)-I+armA (detection rate of 25.49%), aac(3)-I+aph(3')-I+ant(3″)-I+armA (detection rate of 21.57%) and ant(3″)-I+armA (detection rate of 12.75%) being the most prevalent gene profiles. The values of chi-square tests showed correlation of armA, ant(3″)-I, aac(3)-I, aph(3')-I and aac(6')-Ib with HLAR. armA had significant correlation (contingency coefficient 0.685) and good contingency with HLAR (kappa 0.940). The high rates of HLAR may cause a serious problem for combination therapy of aminoglycoside with β-lactams against A. baumannii infections. As armA was reported to be able to cause high level aminoglycoside resistance to most of the clinical important aminoglycosides (gentamicin, amikacin, tobramycin, etc), the function of aminoglycoside modifying enzyme gene(s) in A. baumannii carrying armA deserves further investigation.

As d-amino acids play important roles in the physiological metabolism of bacteria, combination of d-amino acids with antibiotics may provide synergistic antibacterial activity. The aim of the study was to evaluate and activity of d-serine alone and in combination with -lactams against methicillin-resistant (MRSA) strains, and to explore the possible sensitization mechanisms. The activity of d-serine, -lactams alone and in combinations was evaluated both by standard MICs, time-kill curves and checkerboard assays, and by murine systemic infection model as well as neutropenic thigh infection model. An synergistic effect was demonstrated with the combination of d-serine and -lactams against MRSA standard and clinical strains. Importantly, the combinations enhanced the therapeutic efficacy in the animal models as compared to -lactam alone groups. Initial mechanism study suggested possible revision of d-alanine-d-alanine residue to d-alanine-d-serine in peptidoglycan by adding of d-alanine in the medium, which may cause decreased affinity to PBPs during transpeptidation. In conclusion, d-serine had synergistic activity in combination with -lactams against MRSA strains both and . Considering the relatively good safety of d-serine alone or in combination with -lactams, d-serine is worth following up as new anti-MRSA infection strategies.

Polymyxin B and polymyxin E (colistin) are presently considered the last line of defense against human infections caused by multidrug-resistant Gram-negative organisms such as carbapenemase-producer Enterobacterales, Acinetobacter baumannii, and Klebsiella pneumoniae. Yet resistance to this last-line drugs is a major public health threat and is rapidly increasing. Polymyxin S₂ (S₂) is a polymyxin B analogue previously synthesized in our institute with obviously high antibacterial activity and lower toxicity than polymyxin B and colistin. To predict the possible resistant mechanism of S₂ for wide clinical application, we experimentally induced bacterial resistant mutants and studied the preliminary resistance mechanisms. Mut-S, a resistant mutant of K. pneumoniae ATCC BAA-2146 (Kpn2146) induced by S₂, was analyzed by whole genome sequencing, transcriptomics, mass spectrometry and complementation experiment. Surprisingly, large-scale genomic inversion (LSGI) of approximately 1.1 Mbp in the chromosome caused by IS26 mediated intramolecular transposition was found in Mut-S, which led to mgrB truncation, lipid A modification and hence S₂ resistance. The resistance can be complemented by plasmid carrying intact mgrB. The same mechanism was also found in polymyxin B and colistin induced drug-resistant mutants of Kpn2146 (Mut-B and Mut-E, respectively). This is the first report of polymyxin resistance caused by IS26 intramolecular transposition mediated mgrB truncation in chromosome in K. pneumoniae. The findings broaden our scope of knowledge for polymyxin resistance and enriched our understanding of how bacteria can manage to survive in the presence of antibiotics.