Abstract Survival analysis has been widely used in the field of medical research. The Cox proportional hazard model is commonly used, but its practical application is limited. Machine learning method can compensate for the shortcomings of the Cox proportional hazard model in terms of nonlinear data processing and prediction accuracy. This article reviewed the advance of machine learning methods represented by neural networks, within the field of survival analysis, and highlighted the principles and benefits of three machine learning methods that DeepSurv, Deep-Hit and random survival forest, providing methodological insights for the analysis of complex survival data.

Objective To evaluate the relationship between dyslipidemia and abdominal aortic aneurysm (AAA), with which as a theory base and proof we may further study about the mechanism of atherosclerosis (AS) leading to AAA. Methods Thirty abdominal aortic aneurysm patients in Guangdong General Hospital from 2013 to 2014 were enrolled into the experimental group and 26 healthy people into the control group. The serum levels of total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), lipoprotein a (Lpa), nonestesterified fatty acid (NEFA), homocysteine (HCY), apolipoprotein A (ApoA) and apolipoprotein B(ApoB)were tested in the study. The statistical significance of the difference of them was examined by the independent two-sample t-test. Result The serum TG and HCY level in the experimental group were significantly higher than those in the control group (P<0.05). The serum ApoA and HDL level in the experimental group were significantly lower than those in the control group (P<0.05). The serum levels of TC, LDL, Lpa, NEFA and Apo B had no significant difference in both groups (P > 0.05). Conclusion The serum levels of TG and HCY are increased and the levels of Apo A and HDL are decreased in patients with AAA.

Objective To evaluate the inhibitory effect of valdecoxib on the growth of the cancer cell lines and involvement of COX-2 in this inhibition. Methods Western blotting and immunocytochemistry were used to detect the expression of COX-2. MTT assay was used to determine inhibitory effect of the drugs on the cell growth. The content of PGE_ 2 in cell medium was determined with PGE_ 2 ELISA kit. Results ①Clone 26 cells expressed high levels of COX-2, whereas BGC-823,HGC-27 and SK-OV-3 cell had no COX-2 expression. ②Valdecoxib inhibited the growth of BGC-823, HGC-27, SK-OV-3 and clone 26 cells, with a IC_ 50 of 110.7, 99.2, 113.3, 117.6 ?mol/L, respectively. ③The inhibitory effect of these drugs on BGC-823 and clone 26 cell was in the descending order of valdecoxib, SC-560 and indomethacin. ④PGE_ 2 did not antagonize the effect of valdecoxib, SC-560 and indomethacin on BGC-823 and clone 26 cells. ⑤The inhibitory effect of valdecoxib and indomethacin on the growth of clone 26 cells was not compatible with that on PGE_ 2 . Conclusion The inhibitory effect of valdecoxib on cell growth is not related to its effect on COX-2.

ObjectiveTo observe the expression of Twist protein, vascular endothelial growth factor (VEGF) mRNA and protein in laryngeal squamous cell carcinoma(LSCC) and their relation to clinical pathological characteristics, and aslo debate their effect and clinical application in carcinogenesis, developing of LSCC. MethodMolecular hybridization in situ was carried to detect VEGF mRNA, and immunohistochemistry S-P method was carried to detect the expression of Twist protein and VEGF protein in 80 cases of LSCC, 30 cases of paraneoplastic tissue. ResultsThe expression of Twist protein, VEGF mRNA and protein was related to TNM stage, T stage, thyroid cartilage involvement, lymph node metastasis and distance metastasis (P ＜ 0.05 or ＜ 0.01 ). The expression of Twist protein and VEGF protein was related to differentiated degree (P ＜ 0.01 or ＜ 0.05), however, the expression of VEGF mRNA was not related to differentiated degree (P ＞ 0.05 ). The expression of Twist protein was positively related to the expression of VEGF protein in LSCC (r =0.334, P ＜ 0.01 ) ; and the expression of VEGF mRNA was positive correlation to the expression of VEGF protein (r =0.484,P ＜ 0.01 ). ConclusionsOverexpression of Twist protein and VEGF mRNA and protein might play a joint action in the carcinogenesis, development of LSCC. Combined detection of Twist protein and VEGF mRNA and protein has vital significance in predicting the invasion and metastasis of LSCC, which might be an index to judge the biological behavior of LSCC.

Epidemiology,as a major subject in the field of public health science,plays a pivotal role in the construction and development of disease prevention and control system.It is also vital for the public health system to improve the emergency response ability and to cultivate high-quality talents.After analyzing current situation of graduate education of epidemiology,we found some problems.In our research,deepgoing dissection was carried out and possible solution was provided.

AIM: To look for harmfulless anti-leukemia drug with selective high performance, lethal effect of small hairpin RNA (shRNA) on VEGFR2 gene expression of tumor cell line HL60 in vitro.METHODS: The most effective VEGFR2 siRNA was designed and screened. The shRNA oligo was designed and pU6/VEGFR2 entry clone was constructed. HL60 was transfected transiently and vascular endothelial growth factor receptor 2(VEGFR2) expression was tested with MTT assay, RT-PCR and Western blotting. The expression clone was constructed and cotransfected with ViraPowerTM Packaging Mix into 293FTTM cells to produce Lentiviral vectors harboring Lenti6/shVEGFR2. The virion supernatant was added into HL60 cells and VEGFR2 gene inhibitory effect was determined. RESULTS: The inhibitory rates of VEGFR2 siRNA c were high. VEGFR2 expression in HL60 was inhibited by using pU6/VEGFR2 entry clone constructed with shRNA and pENTRTM/U6. For HL60 cells, the inhibitory rate was 84.9%. The expression of VEGFR2 mRNA and protein decreased significantly. 48 hours after transfection of pU6/shVEGFR2 entry clone and transduction of Lenti6/shVEGFR2 expression clone, the cell inhibitory rates were similar. Cell growth inhibitory rate of entry clone descended rapidly after this time point, the expression clone changed slowly, reaching the peak at 96 hours, dropped slightly, having no significance deviation. CONCLUSION: in vitro, VEGFR2 shRNA using lentiviral vector blocks VEGF/VEGFR2 self-secretion in HL60 cells, which inhibits leukemia development.

AIM:Xaf1-Saos inducible cell lines,which contain "gene switch" system were used to detect the effect of Xaf1 on tumor necrosis factor receptor(TNFR) signal pathway and to investigate the mechanism of cooperation between Xaf1 and TNF-? in inducing cell apoptosis.METHODS:Xaf1 on TNFR1 expression was measured by RT-PCR and Western blotting.The effect of NF-?B on Xaf1 induced apoptosis was detected by DNA content flow cytometry after co-transfection.DNA binding activity of NF-?B was identified by gel mobility shift assay and transcription activity of NF-?B was analyzed by luciferase assay and RT-PCR.SAPK/JNK activity was checked by SAPK/JNK assay.RESULTS:Xaf1 did not modulate TNFR1 at protein and mRNA levels.Increased NF-?B activity in cells inhibited Xaf1 induced apoptosis.Expression of Xaf1 impaired modestly TNF-? induced NF-?B DNA binding activation and transcription activation,also modestly reduced SAPK/JNK activity.CONCLUSION:Xaf1 inhibits TNFR signal pathway,partly contributing to cooperation with TNF-? to induce apoptosis.

Objective To investigate the expression of the ternary complex factor Net in human pancreatic carcinoma cell line BxPC3 and its effect on cell proliferation and the expression of c-fos.Methods pEGFP-Net prokaryotic expression plasmid and empty vector pEGFP were transfed into BxPC3 cens by using lipofectamine 2000,then monoclonal cell which stably expressing Net was established.Human pancreatic carcinoma cells proliferation was detected by MTT and flow cytometry.The tuRNA and protein expression of Net and c-fos in BxPC3 cells were detected by real.time PCR and Western blot.Results Net was low expressed in BxPC3 cells.After pEGFP-Net transfection,Net wag stably expressed and the expression of c-fos was inhibited,cell proliferation was also inhibited after pEGFP-Net transfection,the inhibitory rates at the 3rd, 5th,7th day was 38.81%,55.34%and 56.92%respectively,which were significantly higher than those in the empty vector group(5.09%,12.42%,8.6%,P<0.05).G_0/G_1 phase cell was(61.79±5.67)%,which were significantly higher than(45.14±3.37)%in the empty vector group(P<0.05).Conclusions The ternary complex factor Net could inhibit pancreatic carcinoma cell line BxPC3 proliferation.Its mechanism was possibly repressing expression of oncogene c-fos.

Objective To observe the change of invasion and migration of the pancreatic carcinoma cell line SW1990 transfeeted with EEF1A2 gene.Methods Pancreatic carcinoma cell line SW1990 was transfected with EEF1A2 by recombinant adenovirus vector.The alteration of motility、invasion and adhesion property of SW1990 was evaluated by wound healing assay,transwell With or without Matrigel basement membrane and adhesion assay.Results Wound healing assay revealed that EEF1A2 enhanced cell motility and transwell assay with Matrigel indicated that the average numbers of transwell cells with EEFlA2 was increased from 23.25±5.23 to 65.42±8.24(P＜0.05).The adhesive rate was substantially increased in EEF1A2 transfected SW1990 cells compared with control cells.Conclusions EEF1A2 gene can promote the migration.invasion and adhesion ability of pancreatic cancer cell in vitro.It is indicated that EEF1A2 may involve in the development of human pancreatic cancer by influencing cell biological characteristics.

Objective To investigate the effects of EEF1 A2 on growth and proliferation of the human pancreatic cancer cell line SW1990. MethodsThe EEF1 A2 gene was introduced into pancreatic cancer cell line SW1990 by adenovirus vector. The effects of EEF1 A2 on the growth of human pancreatic cancer cell were measured by MTT. Cell cycle was detected by flow cytometry and cell growth rate was examined by soft agar cloning formation test. ResultsAfter EEF1A2 induction, the expression of EEFA1 A 2 mRNA in pancreatic cancer cell line SW1990 increased, value of A750 at 72 h was 1. 2996 ±0. 2091, number of cells was 81250, cloning efficiency at 14 d was 82%, all of these parameters were significantly higher than those in the groups of blank adenoviras vector and PBS groups (P <0.05 ) ; the percentage of G1 phase cell was 28.5%, which was significantly lower than those in the groups of blank adenovirus vector and PBS groups; the percentage of Sphase ceil was 60.9%, which was significantly higher than those in the groups of blank adenovirus vector and PBS groups (P < 0.05 ). ConclusionsEEF1 A2 gene significantly enhanced cell growth and proliferation in human pancreatic cancer in vitro.