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.

BACKGROUND:Very smal embryonic-like stem cells are a kind of non-hemopoietic stem cells, which have similar biological characteristics to embryonic stem cells. But the method of its culture and in vitro proliferation is rarely reported. Studies have speculated that human embryonic fibroblasts can provide a good microenvironment for in vitro culture and proliferation of very smal embryonic-like stem cells.
OBJECTIVE:To isolate and cultivate human embryonic fibroblasts derived from human embryonic trunks and to establish a feeder layer culture system of human embryonic fibroblasts for culturing very smal embryonic-like stem cells derived from human bone marrow.
METHODS:The human embryonic fibroblasts were isolated from the subcutaneous connective tissue of human embryos at pregnant 5-9 weeks using trypsin digestion method. Different concentrations of mitomycin C were used to pretreat feeder layers, which were used for cultivating very smal embryonic-like stem cells derived from human bone marrow. The effects of human embryonic fibroblasts and feeder layers were assessed by cel morphology and growth curves.
RESULTS AND CONCLUSION:The human embryonic fibroblasts were successful y isolated and cultivated from human embryos, and they could be passaged beyond the 24th generation. The biologic characteristics of the cells had no changes after passage and cryopreservation. The optimal concentration of mytomcin C to inhibit proliferation of human embryonic fibroblasts was l2 mg/L for 3 hours. The human embryonic fibroblasts derived from human embryos are successful y isolated and cultivated and to produce feeder layers for very smal embryonic-like stem cells derived from human bone marrow.

The objective structured teaching evaluation (OSTE) is a new method for training and objective assessment of the teaching ability of clinical faculty by using standardized students and teaching scenario.It is mainly used to evaluate training programs,train teaching skills and assess teaching ability of clinical faculty.The differences and association between teaching ability,teaching skills and teaching scenario should be clarified before designing OSTE.Although there are some differences in various studies,OSTE can be summarized into two aspects:teaching administration knowledge and special teaching skills.Given the great potential of OSTE in training and assessing faculty,medical educators in general should actively explore its concept and application.

Objective To study the CT features of thoracic sarcoidosis in senile and pre senile patients. Methods The findings in 25 patients(14 elderly patients and 11 pre senile patients) manifesting thoracic sarcoidosis were reviewed. Results Nine patients with typical findings and sixteen patients with atypical findings were reported at retrospective presentation. The atypical patterns at CT included mediastinal adenopathy with unilateral hilar adenopathy( n =3, 3/25), mediastinal adenopathy alone ( n =7, 7/25), unilateral hilar adenopathy alone ( n =1, 1/25), and lung abnormal findings without any mediastinal and/or hilar adenopathy ( n =5, 5/25). The latter 5 patients were misdiagnosed at the first clinical consultation. Conclusions The thoracic sarcoidosis in the elderly often manifests atypical patterns, and the recognition of the key point is of importance and helpful for the definite diagnosis.

Objective To study the CT appearances in the atypical thoracic sarcoidosis Methods Chest CT findings of 43 patients with proven sarcoidosis were reviewed retrospectively Results 22 cases (51 16%) had atypical thoracic sarcoidosis findings at presentation The atypical patterns on CT included mediastinal adenopathy alone ( n =9) or in combination with unilateral hilar adenopathy ( n =6), and unilateral hilar adenopathy alone ( n =1) 6 patients had abnormal findings in the lung alone without adenopathy, and they all had been misdiagnosed 18 atypical cases (81 82%) occurred in patients older than 50 years, whereas 4 atypical cases (18 18%) occurred in patients younger than 50 years Conclusion Half patients with thoracic sarcoidosis have atypical CT appearances, it frequently occurs in elderly patients, and the diagnosis is easily mistaken on CT scan

This paper introduces the application of P80C552, a microprocessor with ADC, to microwave curer. The principle and functions of the curer presented, the hardware and software designs of its intelligentized control system are described in detail. The designs, making the curer reliable and stable, prove practical.

Objective To evaluate the efficacy and safety of interventional occlsu ion operait no by analyizn g thes urgical data of 23 csa es of infants with patent ductusa rteriosus complicated with middle and severe pulmo an ry arterial hypertension.Methods Teh 23 cases of infants wiht patne t ductus arteriosus com-plicated with middlea nd severe pulmonary arterial hypertensionw ere collected in the hospital from January 2011 to December2014 .These infatn s rce eived transcateh ter occlusion with intravenuo s anesthesia after the preoperative examination.The operation procse s included:right ventriculography and pulmonary atr ery pressure tested,then lateral angiogar phy of descending aorta was performed to observe the type and size of patent ud ctus atr eriosus and measure ascending aorta,descending aortic pressure,and recorded the pressure re-spectively.1 ml blood sample of ascending aorta,pulmonary artery and inef rior vena vein respectively was used for gas analysis.All these data was used to calculate pulmonary vascular resistance.After tried to plug-ging effectiveyl we can release the occluder.In the postoperative 24 h,1 month,3 months,the infants should be measured with Doppler echocardiography,chest X ray and electrocardiogram examination.Results The clinical symptoms disappeared and the short-term follow-up was not associated with the complications of interventional therapy.Th e comparison of the pressure changes before and after the operation were performed as following, aortic per ssure decreased [ preoperation ( 68.3 ±17.5 )/( 21.4 ±3.7 ) mmHg, postoperation (52.4 ±8.7)/(15.6 ±3.5) mmHg,1 mmHg=0.133 kPa],ascending aorta pressure increased(preoperation (83.5 ±5.9)/(51.3 ±3.6) mmHg,postoperation(88.2 ±5.1)/(52.4 ±2.7) mmHg),and descending aorta pressure increased ( preoperation ( 81.4 ±3.3 )/( 48.2 ±2.7 ) mmHg, postoperation ( 86.5 ±4.7 )/(51.5 ±3.2) mmHg), the differences were statistically significant before and after surgery ( t =5.455/3.945 ,P<0.01;t=-2.696/-1.193 , P<0.05; t=-4.167/-3.745 , P<0.01 ) .Conclusion Under conditions of mastering the appropriate operation time and strengthening the management of the perioperative management,transcatheter measurement is safe and effective for infants with patent ductus arteriosus compli-cated with middle and severe pulmonary arterial hypertension.

Crossbite of upper and lower second molars is a common malocclusion. It is difficult to treat such cases. 4 kinds of treatments according to different situations are recommended. One is a mutual elastics on the upper and lower teeth. The second method is to move upper and lower teeth by archwire lingually and bucally. The third is to extract the second molars, while the third molars drift automatically. The fourth is using mini-implant as an anchorage to move the teeth to correct position. This article evaluated the advantages and disadvantages of the 4 kinds of methods. We also discussed how to choose the appliances as well as what we should pay attention to treat this malocclusion.

Objective To compare RNA interference (RNAi) with imatinib in killing K562 cells. Methods Design effective shRNA sequences special for bcr-abl silencing and insert them into the eukaryotic expression vector for RNAi by gene engineering. The recombinant plasmi(ts were then transfected into K562 cells. 48 hours later, the efficiency of transfection was identified by fluorescent microscope, bcr-abl mRNA level was detected by RT-PCR. Another group of K562 cells were treated respectively by imatinib with different concentration. All groups of K562 cells were finally analyzed in apoptosis, cell proliferation and phosphotyrosine-containing proteins. Results Both RNAi and imatinib induced apoptosis, decreased proliferation and reduced phosphotyrosine-containing proteins. Conclusion BNAi can kill K562 cells successfully as imatinib, and it may be a promising way to treat CML patients in clinic, especially for those who fail in imatinib or other chemotherapy.

Objective To investigate the distribution and drug resistance of major pathogens for urinary tract infections in the First Affiliated Hospital of Nanjing Medical University.Methods Strains from midstream urine culture of patients with urinary tract infections were collected during January 1 and December 31,2011.All strains were identified by API system,and disk diffusion method was used for drug sensitivity test.Results Totally 1129 strains were isolated,in which 667 (59.1％ ) were Gram-negative strains,266 (23.5％) were Gram-positive strains,and 196 (17.4) were Candida.Among Gram-negative strains,Escherichia coli,Klebsiella pneumoniae and Proteus mirabilis were highly sensitive to carbapenem antibiotics; while Acinetobacter baumannii and Pseudomonas aeruginosa were highly resistant to most antibiotics including cephalosporins and penicillinase inhibitor,and the resistance rates were over 50％.Among Gram-positive strains,the major strains Enterococcus avium and Enterococcusfaecalis were completely sensitive to vancomycin and teicoplanin,and highly sensitive to linezolid (resistance rate below 10％ ).Candida albicans and Candida glabrata were highly resistant to voriconazole and fluconazole (with the resistance rates of 47.2％ - 60.0％ ), but were completely sensitive to amphotericin and nystatin.Conclusion Gram-negative strains account for most urinary tract infections in the First Affiliated Hospital of Nanjing Medical University with high drug resistance rates.