【Abstract】Objective To explore the application of RNA interference (RNAi) in colorectal cancer gene therapy. Methods The related literatures in recent years were reviewed. Results RNAi causes a high effective and distinctive degradation of mRNA homologous in sequence to the dsRNA. This new technology has been successfully applied to research the genesis and the growth of colorectal cancer.Conclusion RNAi has been a new focus in gene therapy for colorectal cancer.
ObjectiveTo summarize the experience of diagnosis and treatment on primary gastric lymphoma. MethodsThirtyseven patients, proved by pathology, were included in the study. ResultsAmong clinical presentation, the upper abdominal pain, intestinal bleeding, and weight loss were common. Only 4 cases were diagnosed as PGL in 33 cases with the examination of Xray barium meal, 88.5% ( 23 of 26 cases) were missdiagnosed as gastric ulcer under gastroscopy. All cases underwent operation, among them 33 had been performed a radical operation. The survival period was over 5 years in 12 of 25 patients who have been followed up. ConclusionThe multiple biopsy sampling from submucosal layer via gastroscope may improve diagnostic rate on primary gastric lymphoma. Operative removal of the tumor should be the first choice of treatment. Additional chemotherapy after the surgery increases the fiveyear survival rate.
Dose-response meta-analysis, as a subset of meta-analysis, plays an important role in dealing with the relationship between exposure level and risk of diseases. Traditional models limited in linear regression between the independent variables and the dependent variable. With the development of methodology and functional model, Nonlinear regression method was applied to dose-response meta-analysis, such as restricted cubic spline regression, quadratic B-spline regression. However, in these methods, the term and order of the independent variables have been assigned that may not suit for any trend distribution and it may lead to over fitting. Flexible fraction polynomial regression is a good method to solve this problem, which modelling a flexible fraction polynomial and choosing the best fitting model by using the likelihood-ratio test for a more accurate evaluation. In this article, we will discuss how to conduct a dose-response meta-analysis by flexible fraction polynomial.
The aggregate data drug information system (ADDIS) software is a non-programming software which is based on the Bayesian framework and using the Markov chain Monte Carlo (MCMC) method for prior assessment and implementation. The operation is fairly easy for users. The consequent results and relevant plots could be output automatically by the software after users assess the consistency of model and convergence diagnostics. The major disadvantage of ADDIS is the more complicated data entry. This article introduces how to perform network meta-analysis using ADDIS software.
Retinopathy of prematurity (ROP) is a serious ophthalmic disease threatening the vision of premature infants, characterized by abnormal retinal vascular development and pathological neovascularization. Its pathogenesis follows a two-stage model of “early hyperoxia inhibiting angiogenesis - late hypoxia promoting neovascularization,” in which oxidative stress damage, inflammatory immune activation, and abnormal expression of growth factors such as vascular endothelial growth factor and insulin-like growth factor-1 play key roles. Current studies indicate that the occurrence of ROP is closely associated with maternal factors (such as gestational hypertension, diabetes, smoking during pregnancy) and fetal factors (including low birth weight, low gestational age, inappropriate oxygen therapy, anemia, blood transfusion, multiple pregnancies, nutritional imbalances, infections, and genetic susceptibility), among which low birth weight and low gestational age are independent risk factors, while the clinical management of oxygen therapy parameters (duration, concentration, and fluctuations) is particularly important. Given the rapid progression, high blindness rate, and poor prognosis of ROP, there is an urgent need to achieve early precise identification and intervention through multifactorial integration models. Future research should further explore the interaction mechanisms of risk factors and develop individualized prevention and treatment strategies to improve the long-term quality of life for affected children.
Objective To systematically review the correlation between polymorphism of DNA methyltransferase 1(DNMT1) rs16999593 and the susceptibility of breast cancer. Methods Databases such as PubMed, EMbase, Web of Science, Chinese Biomedical Literature Database, CNKI, WanFang, and VIP database were searched from inception to Mar. 2017 to collect case-control studies on the correlation between DNMT1 rs16999593 C/T polymorphism and the susceptibility of breast cancer. Two reviewers independently identified the literatures according to inclusion and exclusion criterias, extracted data, and assessed the quality of the included studies. The meta-analysis was performed by using RevMan 5.3 software. Results A total of 5 studies involving 1 741 cases and 1 917 control subjects were included. The results of meta-analysis showed that, dominate model ［TT+TC vs. CC: OR=0.63, 95% CI was (0.30, 1.30), P=0.21］, homozygous model ［TT vs. CC: OR=1.01, 95% CI was (0.70, 1.47), P=0.95］, heterozygous model ［TC vs. CC: OR=0.44, 95% CI was (0.18, 1.04), P=0.06］, and additive model ［T vs. C: OR=1.29, 95% CI was (0.90, 1.86), P=0.16］ were not significantly related to breast cancer, but recessive gene model was related to breast cancer ［TT vs. TC+CC: OR=1.74, 95% CI was (1.01, 3.00), P=0.04］. Conclusion The current studies showed that, DNMT1 rs16999593 TT genotype decreases the susceptibility of breast cancer.
R Software is an open, free of use and charge statistical software which has a powerful graphic capability; however, it requires more complex codes and commands to perform network meta-analysis, which causes errors and difficulties in operation. WinBUGS software is based on Bayesian theory, which has a powerful data processing capability, and especially its codes are simple and easy to operate for dealing with network meta-analysis. However, its function of illustrating statistical results is very poor. In order to fully integrate the advantages of R software and WinBUGS software, an R2WinBUGS package based on R software has been developed which builds a “bridge” across two of them, making network meta-analysis process conveniently, quickly and result illustration more beautiful. In this article, we introduced how to use the R2WinBUGS package for performing network meta-analysis using examples.
Objectives To systematically review the efficacy of polytetrafluoroethylene (PTFE) covered stent grafts vs. bare stent grafts in transjugular intrahepatic portosystemic shunt (TIPS) for portal hypertension. Methods PubMed, EMbase, The Cochrane Library, and ClinicalTrial.gov were searched online to collect randomized controlled trials (RCTs) and cohort studies of PTFE-covered stent grafts vs. bare stent grafts for portal hypertension from inception to Jan 11th, 2017. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Meta-analysis was then performed by RevMan 5.3 software. Results A total of 4 RCTs and 11 cohort studies involving 2 422 patients (1 070 PTFE-covered stent grafts patients and 1 352 bare stent grafts patients) were included. The results of meta-analysis showed that compared with the bare stent grafts group, the PTFE-covered stent grafts group had higher patency rate of intrahepatic shunt (HR=0.38, 95%CI 0.31 to 0.47, P<0.000 01) and survival rate (HR=0.59, 95%CI 0.44 to 0.79,P=0.000 5), lower postoperative complications rate (including gastrointestinal bleeding and refractory ascites) (HR=0.44, 95%CI 0.33 to 0.58, P<0.000 01) and encephalopathy rate (HR=0.76, 95%CI 0.57 to 0.99,P=0.05). Conclusions Current evidence shows that compared with the bare stent grafts, the PTFE-covered stent grafts could effectively improve patency rate of intrahepatic shunt and survival rate with less postoperative complications rate and encephalopathy rate. Due to limited quality and quantity of the included studies, more high quality studies are required to verify above conclusions.
Network plots can clearly present the relationships among the direct comparisons of various interventions in a network meta-analysis. Currently, there are some methods of drawing network plots. However, the information provided by a network plot and the interface-friendly degree to a user differ in the kinds of software. This article briefly introduces how to draw network plots using the network package and gemtc package that base on R Software, Stata software, and ADDIS software, and it also compares the similarities and differences among them.