Tumor vaccine is one of the most promising therapeutic strategies in tumor immunotherapy. It promotes the antigen presentation process by delivering tumor antigen and then activates the anti-tumor immune response. As a new class of vaccines, messenger RNA (mRNA) vaccines can activate the immune system to achieve the purpose of immunotherapy by delivering the mRNA sequence of a specific antigen into the body and expressing the corresponding antigen protein. Compared with traditional vaccines, mRNA vaccines have the advantages of a short production cycle, high effectiveness, and strong immunogenicity. In recent years, the application of mRNA vaccines in tumor immunotherapy has attracted widespread attention, but the instability and low delivery efficiency of mRNA limit its application. Nano delivery system can effectively solve the problem of mRNA vaccine delivery, greatly promote the research process and clinical application of mRNA tumor vaccines, and has become a hot spot in the research of mRNA vaccines. In this review, we introduced the mRNA tumor vaccines, focusing on the application of nano delivery system in mRNA tumor vaccines, in order to provide new ideas and new methods for the efficient delivery of mRNA tumor vaccines and tumor immunotherapy.

The Polarographic and voltammetric behavior of Cd (Ⅱ)-meso-tetrakis(p-sulfophenyl)prophyrin (TPPS4） complex was defined and the cyclic voltammetric peak was obtained at 1.200 V (vs. SCE) in 0.3 mol/L NaoH solution. The characteristics of the peak have been examined in detail and the experimental results prove that the peak has adsorption properties. In addition to the number of electrons transferred in the reaction and the complex ratio, the stability const ant (β=1.19×107) was calculated. The peak current was proportional to the concentration of Cd (Ⅱ) over the rang 3×10－7～1×10－5 mol/L and the limit of detection was 6×10－8 mol/L. Furthermore a possible mechanism was proposed for the reduction of the complex.

Biodegradable PLGA [poly(lactide-co-glycolide acid)] have shown significant potential for sustained and targeted delivery of several pharmaceutical agents, including DNA. We reviewed the formulating approaches of PLGA nanoparticles/microspheres as DNA carriers and utilization for gene therapy and vaccine adjuvant.

AIM:To observe the inhibitory effect of interferon-?(IFN-?)on the growth invasiveness and metastasis of human gastric carcinoma cell line BGC-823,and mechanism of its action.METHODS:We detected the influence of IFN-? on the proliferative ability of BGC-823 in cell culture system,the cell vitality with the MTT colorimetric assay,and the cell cycle with flow cytometer(FCM).The regulatory functions of IFN-? to the expression of E-cadherin and matrix metalloproteinase-2(MMP-2)in tumor cells were estimated by immunohistochemical analysis(S-P).The ultrastructural changes of the junction among the tumor cells were observed under electron microscope.RESULTS:IFN-? can significantly inhibit the growth of human gastric carcinoma cell line BGC-823 in a dose-dependent manner.When the concentration of IFN-? was ≥106 U/L,the cell proliferation can be effectively suppressed,the suppression rate was ≥12.2%,and the blockage appeared at the phase of G_1-S of the cell cycle.Under the induction of IFN-?,the expression level of the cell E-cadherin increased while the MMP-2 decreased.The changes on ultrastructure of the cells showed the increased adhesive junctions and the relative compact structure.CONCLUSION:IFN-? can suppress the growth of human gastric carcinoma cell line BGC-823 through its influence on cell cycle.IFN-? can regulate the expression of E-cadherin and MMP-2,make the cell junction closely,so that it has the potential on restricting the invasion and metastasis of gastric carcinoma cells.

OBJECTIVE To investigate the pathogen spectrum and resistance in older cerebrovascular patients with sequelae,so as to provide the evidence for antibiotic applied clinically in these patients. METHODS Retrospective survey of 320 cerebrovascular patients with lower respiratory infection admitted in respiration department from 2003 to 2004 was conducted.RESULTS The occurrence of Gram-negative bacilli(60.41%) in cerebrovascular patients with lower respiratory infection was obviously high,among which the first places were Pseudomonas aeruginosa(24.03%),Klebsiella pneumoniae(13.20%) and Escherichia coli(9.12%),respectively.The Gram-positive bacteria mainly included oxacillin-resistant Staphylococcus aureus(17.12%).In addition,the occurrence rate of fungal infection was increasing,Candida albicans was still the most frequent one(10.30%). The imipenem was the most sensitive to Gram-negative bacilli and more superior than the cefoperazone/sulbactam and ceftazidime.The oxacillcin-resistant S.aureus was still susceptive to vancomycin.CONCLUSIONS The community-acquired lower respiratory infection in oldercerebrovascular patients with sequelae is mixed with multi-resistant bacteria.

Objective To evaluate the safety, efficacy and local control effect of CT- guided radiofrequency ablation (RFA) in treating non-small-cell lung cancer (NSCLC) that is inoperable or the surgical treatment is refused by the patient. Methods Between March 2007 and March 2010 at authors’ hospital, a total of 68 procedures of CT-guided RFA were carried out in 60 patients with early stage NSCLC. The patients included 37 males and 23 females with a mean age of 68.5 years. Pathologically, the lesions included squamous cell carcinoma (n=23, 38.3%), adenocarcinoma (n=31, 51.7%), large cell carcinoma (n=2, 3.3%) and adeno-squamous carcinoma (n=4, 6.7%). The mean diameter of the lesions was 3.8 cm (1.8-6.8 cm). The overall survival rate, cancer-specific survival rate and local progression-free survival rate were evaluated. Results RFA procedure was well tolerated by all patients with an average ablation time of 35 min (18-63 min). The main intraprocedural complication was pneumothorax (n=17, 28.3%). No death occurred during perioperative period. The median local progression-free survival time was 28 months, the median survival time was 32 months, and the one-, 2- and 3-year local progression-free survival rate were 94.6%, 83.1%and 73.6%, respectively. Conclusion For patients with inoperable NSCLC and patients with NSCLC who refuse to receive surgery, CT-guided RFA is a safe and effective treatment. This therapy can significantly improve the local progression-free survival rate.

Medical cell biology is an important basic medical course. Owing to its complex and esoteric knowledge and few lessons, there is a dilemma of teaching and learning. From learning situation analysis, the course team building programs, operation and management of the program, learning evaluation program, the author has conducted exploration and preliminarily proved that the medical cell biology curriculum team learning is conducive to the cultivation of students ' innovation ability and the team cooperation spirit as well as improvement of students ' learning interest, which is worthy of application and promotion.

Objective To assess the value of MSCT and postprocessing techniques in displaying abnormal blood vessels of pulmonary sequestration. Methods Ten patients with pulmonary sequestration proved with operation and pathology underwent both plain and enhanced chest CT scan. The reconstructed images of maximum intensity projection, multiplanar reconstruction and volume rendering were analyzed retrospectively. Results Of 10 patients, intra-lobe type sequestration was seen in 9 patients and extra-lobar type in 1 patient. The lesions located in the left lower lobe in 8 patients and in the right lower lobe in 2 patients. Angiography postprocessing technique displayed abnormal supplying vessels in 9 patients (7 from descending aorta and 2 from abdominal aorta) and displayed the origin, courser, branches and distribution of lesions clearly. Vessels in 9 patients drained into inferior pulmonary veins except in one drained into azygos vein. Conclusion MSCT angiography with postprocessing reconstruction techniques can display abnormalities of pulmonary sequestration clearly and has great value in the diagnosis of pulmonary sequestration, so as might be the first choice in diagnosing pulmonary sequestration.

AIM: To observe the inhibitory effect of interferon-α ( IFN-α) on the growth invasiveness and metastasis of human gastric carcinoma cell line BGC-823, and mechanism of its action. METHODS: We detected the influence of IFN-α on the proliferative ability of BGC-823 in cell culture system, the cell vitality with the MTT colorimetric assay, and the cell cycle with flow cytometer (FCM). The regulatory functions of IFN-α to the expression of E-cadherin and matrix metalloproteinase-2 ( MMP-2) in tumor cells were estimated by immunohistochemical analysis ( S-P). The ultrastructural changes of the junction among the tumor cells were observed under electron microscope. RESULTS : IFN-α can significantly inhibit the growth of human gastric carcinoma cell line BGC-823 in a dose-dependent manner. When the concentration of IFN-α was ≥106 U/L, the cell proliferation can be effectively suppressed,the suppression rate was ≥ 12. 2%, and the blockage appeared at the phase of G1-S of the cell cycle. Under the induction of IFN-α, the expression level of the cell E-cadherin increased while the MMP-2 decreased. The changes on ultrastructure of the cells showed the increased adhesive junctions and the relative compact structure. CONCLUSION: IFN-α can suppress the growth of human gastric carcinoma cell line BGC-823 through its influence on cell cycle. IFN-α can regulate the expression of E-cadherin and MMP-2, make the cell junction closely, so that it has the potential on restricting the invasion and metastasis of gastric carcinoma cells.

Objective: To investigate the effect ofintestinal trefoil factor (ITF) on the transcriptional activity of ITF promoter and to explore the regulatory mechanismofJanus kinase/signal transducersand activators of transcription(JAK/STAT) on ITF promoter. Methods: The 5' flanking sequence of the ITF gene was cloned from human whole blood genomic DNA by PCR. ITF promoter fragment was cloned and inserted into the pGL3-Basic vector to construct recombinant vector. ITF promoter vector was stimulated with ITF at various concentrations and the luciferase activity was measured. The JAK-STAT3 signal transductionpathway was then blocked by a speciifc inhibitor AG490 to determine the signal pathway involved in ITF promoter activity. Results: Restriction endonuclease analysis and DNA sequencing confirmed that the recombinant plasmid, containing ITF promoter, was constructed successfully. After transient transfection, the activity of ITF promoter was increased signiifcantly in the presence of ITF (P<0.05). Blockage of the JAK-STAT3 signal transduction pathway with AG490 signiifcantly reduced the ITF promoter activity (P<0.05). Conclusion: ITF increases the transcriptional activity of ITF promoter via the JAK-STAT3 signal transduction pathway.