Objective To systematically review the dose-response relationship between cadmium exposure and the risk of stroke onset. Methods The PubMed, Web of Science, Cochrane Library, Embase, CNKI, VIP, WanFang Data, and CBM databases were electronically searched to collect studies related to objectives from inception to June 2024. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies. Meta-analysis was then performed using Stata 15.1 software. Results There were 10 studies that involved 28 250 participants, and 7 of them were prospective cohort studies and 3 were case-control studies. Meta-analysis results showed that cadmium exposure significantly increased the risk of stroke (RR=1.39, 95%CI 1.20 to 1.59, P<0.01), blood cadmium exposure significantly increased the risk of stroke (RR=1.79, 95%CI 1.34 to 2.25, P<0.01), urinary cadmium exposure significantly increased the risk of stroke (RR=1.30, 95%CI 1.09 to 1.52, P<0.01). Blood cadmium exposure had a significantly nonlinear dose-response relationship associated with an increased risk of stroke (χ2=8.56, P<0.05). The risk of stroke increased by 15% with the blood cadmium exposure concentration of 0.8 μg/L (RR=1.15, 95%CI 0.98 to 1.36), and 51% with the blood cadmium exposure concentration of 1.2 μg/L (RR=1.51, 95%CI 1.14 to 2.01) than those without blood cadmium exposure. Urinary cadmium exposure had significantly linear dose-response relationship associated with an increased risk of stroke (χ2=2.47, P=0.12). The risk of stroke increased by 26% with the urinary cadmium exposure concentration of 0.8 μg/g (RR=1.26, 95%CI 1.20 to 1.31), and 31% with the urinary cadmium exposure concentration of 1.2 μg/g (RR=1.31, 95%CI 1.27 to 1.36) than those without urinary cadmium exposure. Conclusion Cadmium exposure increases the risk of stroke. There was a significant dose-response relationship between cadmium exposure and the risk of stroke.
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.
ObjectivesTo compare different formula calculated dosages with the actual doses of warfarin from patients in Beijing Hospital so as to investigate suitable warfarin dosing models for Chinese patients.MethodsOne hundred and three Chinese patients with long-term prescription of warfarin were randomly selected from Beijing Hospital from July 2012 to May 2013. The CYP2C9 and VKROC1 genotypes and basic statistical information were collected. SPSS 18.0 software was used to compare the differences between different formula calculated dosages and the actual dosages of warfarin.ResultsFive genotypes were found in 103 patients, including: CYP2C9 AA genotype + VKORC1 AA genotype (n=72, 69.9%), CYP2C9 AA genotype + VKORC1 AG genotype (n=17, 16.5%), CYP2C9 AC genotype + VKORC1 AA genotype (n=10, 9.7%), CYP2C9 AC genotype + VKORC1 AG genotype (n=3, 2.9%) and CYP2C9 AA genotype + VKORC1 GG genotype (n=1, 1%). Compared with the actual dosages of warfarin, the degree of coincidence was highest for dosages calculated by Jeffrey’s formula.Conclusions Using Jeffrey’s formula to calculate warfarin dosages may be more suitable for Chinese patients with using long-term warfarin. Due to limited sample size, prospective and large sample size studies are required to verify the above conclusion.
ObjectiveTo compare the radiation dose distribution in irradiated target area and organs at risk among conventional radiotherapy, conformal radiotherapy and semi-field conformal radiotherapy in Graves' ophthalmopathy patients. MethodsThirty patients with Grave's ophthalmopathy treated between January 2010 and December 2012 were included in this study.CT scan was performed to obtain images of each patients; three-dimensional planning system (3D-TPS) was done to design conventional radiotherapy, conformal radiotherapy and semi-field conformal radiotherapy for each patient.Then, we counted the standard deviation of study parameters for each radiotherapy technique, and the results were compared among the three groups. ResultsAverage irradiation dose in target area of patients accepting conventional irradiation, conformal irradiation and semi-field conformal irradiation therapy was not significantly different (P > 0.05).V95 and the conformity index values of conformal irradiation and semi-field conformal irradiation therapy were better than those of the conventional irradiation therapy (P < 0.001), while no significant difference between conformal irradiation and semi-field conformal irradiation therapy was detected (P > 0.05).Patients accepting conventional irradiation got the highest cumulative irradiation dose in eye lens, while patients accepting semi-field conformal irradiation therapy got the lowest irradiation dose in eye lens, and the differences were significant (P < 0.05).Patients accepting conventional irradiation got the highest cumulative irradiation dose in pituitary, while cumulative irradiation dose in pituitary in patients accepting conformal irradiation and semi-field conformal irradiation therapy was not significantly different (P > 0.05). ConclusionsConformal irradiation and semi-field conformal irradiation techniques are superior to conventional irradiation technique, with a better target conformal degree and higher does distribution in target area, as well as a lower radiation dose in normal tissues surrounding target area.Semi-field conformal irradiation technique has a better performance than conformal irradiation therapy in eye lens protection.
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.
ObjectiveTo systematically review the dose-effect relationship between resistance exercise intervention and lower extremity muscle strength and function enhancement in the aging. MethodsEBSCO, PubMed, Web of Science, CNKI, VIP, and WanFang Data databases were electronically searched to collect randomized controlled trials (RCTs) on the effects of resistance exercise on muscle strength and function of the lower extremities in older adults from inception to July 2022. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. A network meta-analysis was then performed by using RevMan 5.4 and Stata 15.0 software. ResultsA total of 32 RCTs with a total sample size of 1 594 individuals were included. The results of network meta-analysis showed that the elements of resistance exercise prescription: intensity 50%-70% 1RM, period 8-12 weeks, frequency 3-4 times/week, duration 30-45 min, and intervals 1.1-2 min were superior to other doses. ConclusionThe optimal dose of resistance exercise for improving lower extremity muscle strength and function in older adults is moderate exercise intensity (50%-70% 1RM) for 8-12 weeks, 3-4 times per week, 30-45 min per exercise, and 1.1-2 min interval between sets.
Dose-response relationship model has been widely used in epidemiology studies, as well as in evidence-based medicine area. In dose-response meta-analysis, the results are highly depended on the raw data. However, many primary studies did not provide sufficient data and led the difficulties in data analysis. The efficiency and response rate of collecting the raw data from original authors were always low, thus, evaluating and transforming the missing data is very important. In this paper, we summarized several types of missing data, and introduced how to estimate the missing data and transform the effect measure using the existed information.
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.
This article reviews Chinese nomenclature of renal replacement therapy and extracorporeal blood purification currently utilized to manage acute kidney injury and other organ dysfunction syndromes in critically ill patients, based on the recent reports of a consensus expert conference of Nomenclature Standardization Initiative Alliance. We provide a detailed description of the performance characteristics of membranes, filters, transmembrane transport of solutes and fluid, flows, and methods of measurement of delivered treatment, common definitions, components, techniques, and operations of the machines and platforms as well as the renal replacement therapy techniques in detail with the relevant technologies, procedures, operations, and recent developments in other extracorporeal therapies, including therapeutic plasma exchange, multiple organ support therapy, liver support, lung support, and blood purification in sepsis. We believe this nomenclature review will serve future use of terminology in publications, research, clinical operations and therapy platforms to enable consistent data collection and comparison.
In evidence-based practice and decision, dose-response meta-analysis has been concerned by many scholars. It can provide unique dose-response relationship between exposure and disease, with a high grade of evidence among observational-study based meta-analysis. Thus, it is important to clearly understand this type of meta-analysis on software implementations. Currently, there are different software for dose-response meta-analysis with various characteristics. In this paper, we will focus on how to conduct dose-response meta-analysis by Stata, R and SAS software, which including a brief introduction, the process of calculation, the graph drawing, the generalization, and some examples of the processes.