Objective To evaluate the effectiveness and safety of different doses of interferon alfa (INF-α) in the treatment of chronic hepatitis C (CHC). Methods Such databases as MEDLINE, EMbase, CENTRAL, CBM, CNKI, VIP and WanFang Data were searched to collect the randomized controlled trials (RCTs) on different doses of INF-α in the treatment of CHC published before August, 2012. According to the inclusion and exclusion criteria, two reviewers independently screened literature, extracted data and evaluated the quality of the included studies, and then meta-analysis was performed using RevMan 5.0 software. Results A total of 13 RCTs involving 1 442 patients were included. The results of meta-analysis on different doses of INF-α showed that, a) There was no significant difference in the complete response rate between the 3 MU dose group and the 1 MU dose group (RR=0.83, 95%CI 0.52 to 1.32, P=0.43), but there was significant difference in the sustained response rate between those 2 groups (RR=1.89, 95%CI 1.00 to 3.59, P=0.05); and b) No significant differences were found in the complete response rate among the 3 MU dose group, the 6 MU dose group, and the 1 MU dose group. Conclusion INF-α in dose of 3 MU, 3 times daily, is effective in treating CHC, but it would not rule out that higher dose takes more effective action. When INF-α is used to treat CHC, an individualized medication should be applied according to patients’ tolerance and economic status.
Objective To investigate the effect of the synthetic bone morphogenetic protein 2 (BMP-2)derived peptide on the osteogenic induction in the marrow mesenchymal stem cells (MSCs）and to evaluate the osteoinductivity and dosedependence of the BMP-2 derived peptide in vitro. Methods MSCs of 4-week old Wistar rats were separated and cultured. In the 3rd passage, the conditional culture medium was changed, in which the BMP-2-derived peptide in the following doses was added: 300,200, 100, 50, and 0 μg/ml, respectively (Groups A-E). The activity of alkaline phosphatase (ALP）and the amount of calciumdeposition were meassured at 5，10，15 and 20 days during the culture with the conditional culture medium. The real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) was performed to measure the mRNA expressions of collagen type Ⅰ, osteopontin (OPN), and osteocalcin（OCN）and to measure the osteoinductivity of the BMP-2-derived peptide in the different concentrations.Results Under the inverted phase contrast microscope, MSCs cultured in the conditional culture medium for 3-4 days were changed in shape, from long fusiform to short fusiform or polygon. As the concentration of the BMP-2-derived peptide increased, the time for MSCs to change into the osteoblasts decreased. There was a significantly greater level of the ALP activity and amount of the calcium deposition in Groups A and B than in the other groups（Plt;0.05）. However,there was no significant difference between Group A and Group B （Pgt;0.05）. Theresult of FQPCR showed that after MSCs were cultured in the different doses of theconditional culture medium for 14 days, the mRNA expressions of collagen type Ⅰ, OPN andOCN were at higher levels. An increasing order in the level of the cycle threshold (Ct) was found in the following groups: Agt;Bgt;Cgt;D. Almost no expression was found in Group E. The Ct levels were significantly greater in Groups A and B thanin Groups C and D（Plt;0.05）. However, there was no significant difference between Group A and Group B （Pgt;0.05）.ConclusionThe BMP-2-derived peptide can greatly promote differentiation of MSCs into the osteoblasts, the promotion of osteogenesis has a dosedependent pattern, and the best inducing dosage is 200 μg/ml.
Objective To investigate the effects of QUE on proliferation and DNA synthesis of cultured retinal pigment epithelium(RPE) cells with or without EGF. Methods With or without EGF, cultured RPE cells were treated with QUE by various concentrations(200,100,50,1mu;mol/L) and with QUE 200mu;mol/L at different times(24-168 hr), cells proliferation and DNA synthesis were evaluated by cell count method and the uptake of thymidine. The viability of cells was determined by trypanblue exclusion. Results The best concentration of QUE which inhibits proliferation and DNA synthesis of PRE cells was 200mu;mol/L. The significant inhibition effect of QUE occurred at 48hr, and the best inhibition of QUE occurred at 96hr. QUE had more powerful effect of antiproliferation on RPE cells, and the viability of RPE cells was over85%. Conclusion The results suggested that QUE could inhibit the proliferation of RPE cells in a dose-dependent and time-dependent manner, especially inhibit the proliferation induced by EGF stimulating. QUE had no cyto-toxic effect on RPE cells cultured in vitro. (Chin J Ocul Fundus Dis,1999,15:27-29)
Objective According to health technology assessment (HTA) methodology, to assess the efficacy and safety of different doses of metoprolol in the treatment of atrial fibrillation (AF). Methods Based on the principles of HTA, we searched some important medical databases including MEDLINE, EMBASE, The Cochrane Library and CMCC, as well as several national special heart disease databases and side effect centers. We selected eligible studies based on the inclusion and exclusion criteria and critically assessed their quality. Results Intravenous metoprolol 10 mg - 15 mg could control rapid ventricular rate in patients with chronic AF. On either rest or exercise, oral metoprolol 150 mg/d had a better control of rapid ventricular rate than 50 mg/d in patients with chronic AF. For preventing postoperative AF (POAF), the intravenous metoprolol 20 mg group and the 30 mg group could decrease the incidence of POAF compared to the 10 mg group. Oral metoprolol 150 mg/d was more effective than 100 mg/d in preventing POAF. In addition, intravenous metoprolol therapy was well-tolerated and more effective than oral metoprolol therapy in preventing atrial fibrillation after cardiac surgery. Results from several national side effect centers demonstrated that the incidence of adverse reactions associated with metoprolol was low. Conclusion Present evidence showed that high dose of metoprolol was superior to low dose in treating AF, however, the evidence available is insufficient. It is suggested that adequate evidence through further studies are needed. The safety profile of different doses of metoprolol is similar.
Objective To assess the rationale for including rifampicin150/isoniazid75/ethambuto/275mg fixed dose, combination oral tablets/3-FDC R150H75E275/ in the WHO Model List of Essential Medicines (WHO EML) for treatment of category II tuberculosis (TB II) and to provide evidence for the updating of national guidelines. Methods We searched Chinese Biomedical Database (CBM, 1978 to 2006), The Cochrane Library, Issue 4, 2006, the Database of Abstracts of Reviews of Effects (1994 to 2006, the Centre for Reviews and Dissemination website), MEDLINE (1950 to 2006), EMBASE (1974 to 2006), BIOSIS Previews (1997 to 2006), websites for grey literature and the references of studies. We applied inclusion and exclusion criteria in assessing the studies we found and eligible studies were graded following an assessment of their quality. Results Thirty-six randomized controlled trials, 4 controlled clinical trials, 11 descriptive studies and 5 WHO/national guidelines were included. Rifampicin (R), isoniazid (H) and ethambutol (E) were used in the ccontinuation phase (CP) of TB II in guidelines of WHO and high tuberculosis (TB) burden countries, but the course of treatment and dosage regimens varied. R, H and E were also widely used in conditions of pulmonary tuberculosis (PTB), extrapulmonary tuberculosis (EPTB) and pulmonary diseases caused by nontuberculous mycobacteria (NTM).Conclusions It is recommended that FDC RHE be included in WHO EML for the treatment of TB II.The suggested dosage ratio of RHE is 1:1:2, which needs to be adjusted based on more solid clinical evidence. High quality clinical studies and systematic reviews on the effectiveness, safety, economics and applicability of WHO and national guidelines and their outcomes in high TB burden countries are needed to guide their updating, promote rational resource allocation and improve cost effectiveness. Alternative drugs or drug combinations with good profile of effectiveness, safety, economics, and applicability for the prevention and treatment of drug-resistant tuberculosis are also needed to be developed.
Objective To assess the radiation dose and image quality with low-dose multi-detector row CT urography （CTU） for the evaluation of children patients with ureteropelvic junction stenosis （UJS）. Methods In this prospective study， 30 children patients with UJS underwent CTU were classified half-randomly through exam numbers into 3 groups （115 mA， 100 mA， and 75 mA）. Consecutive acquisitions including CT dose index weighted （CTDIw） and dose long product （DLP） were obtained in each patient and compared for each group. Three experienced chest radio-logists were unaware of the CT technique reviewed CT images for overall image quality using a 3-grade scale （excellent， good， and worst）. The data were analyzed using a parametric analysis of variance test and Wilcoxon’s signed rank test. Results The CTDIws of 115 mA group， 100 mA group， and 75 mA group were （7.63±0.83） mGy， （6.29±0.51） mGy， and （4.72±0.18） mGy， respectively， the difference was significant among three groups （F=36.445， P=0.000）. The mean CTDIw reduction was 38.2% in the 75 mA group as compared with 115 mA group （P＜0.001）. The DLPs of 115 mA group， 100 mA group， and 75 mA group were （173.89±29.88） mGy•cm， （145.96±26.21） mGy•cm， and （102.78±12.72） mGy•cm， respectively， the difference was significant among three groups （F=13.955， P=0.000）. The mean radiation dose reduction was 40.9% （75 mA group versus 115 mA group， P＜0.001）. The assessment of image quality was no significant difference with the same protocol and post-processing technique （Wilcoxon’s signed rank test， P＞0.05）. There was a good agreement for image quality scoring among the three reviewers （Kappa=0.736）. Conclusion Low-dose multi-detector row CTU should be considered as a promising technique for the evaluation of children patients with UJS because it could decrease radiation dose and obtain acceptable image quality.
Does-response meta-analysis, which has being developed for more than 30 years, is a type of regression function and can be both linear and non-linear model. It plays an important role in investigating the relationship between dependent and independent variable. With its special advantages, dose-response meta-analysis has been widely used in evidence-based practice and decision. Currently there are several models can be used to perform dose-response metaanalysis with various advantages and disadvantages. It is vital to choose best model to perform dose-response metaanalysis in evidence-based practice. In this paper, we briefly introduce and summarize the methodology of dose-response meta-analysis.
Restricted cubic spline function is an ideal model in trend approximation, which is widely used in doseresponse meta-analysis. The spline function, based on parameter technique, is a smoothly joined piecewise polynomial of each knot, with a cubic polynomial in each sub-interval of the slope which fits well in the non-linear trend by changing the number and (or) the sites of the knots. We have introduced the methodology of linear and non-linear slope model in dose-response meta-analysis in the previous article, and in this one, we will give a more detailed discussion on restricted cubic spline function mainly in the following aspects: model building, parameters pooling and knots selecting.
Dose-response meta-analysis, an important tool in investigating the relationship between a certain exposure and risk of disease, has been increasingly applied. Traditionally, the dose-response meta-analysis was only modelled as linearity. However, since the proposal of more powerful function models, which contains both linear, quadratic, cubic or more higher order term within the regression model, the non-linearity model of dose-response relationship is also available. The packages suit for R are available now. In this article, we introduced how to conduct a dose-response meta-analysis using dosresmeta and mvmeta packages in R.
When investing the relationship between independent and dependent variables in dose-response meta-analysis, the common method is to fit a regression function. A well-established model should take both linear and non-linear relationship into consideration. Traditional linear dose-response meta-analysis model showed poor applicability since it was based on simple linear function. We introduced a piecewise linear function into dose-response meta-analysis model which overcame this problem. In this paper, we will give a detailed discussion on traditional linear and piecewise linear regression model in dose-response meta-analysis.