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Background: The objective of the study was to validate biomechanical characteristics of a 3D-printed, novel-designated fixation plate for treating mandibular angle fracture, and compare it with two commonly used fixation plates by finite element (FE) simulations and experimental testing., Methods: A 3D virtual mandible was created from a patient's CT images as the master model. A custom-designed plate and two commonly used fixation plates were reconstructed onto the master model for FE simulations. Modeling of angle fracture, simulation of muscles of mastication, and defining of boundary conditions were integrated into the theoretical model. Strain levels during different loading conditions were analyzed using a finite element method (FEM). For mechanical test design, samples of the virtual mandible with angle fracture and the custom-designed fixation plates were printed using selective laser sintering (SLS) and selective laser melting (SLM) printing methods. Experimental data were collected from a testing platform with attached strain gauges to the mandible and the plates at different 10 locations during mechanical tests. Simulation of muscle forces and temporomandibular joint conditions were built into the physical models to improve the accuracy of clinical conditions. The experimental vs the theoretical data collected at the 10 locations were compared, and the correlation coefficient was calculated., Results: The results show that use of the novel-designated fixation plate has significant mechanical advantages compared to the two commonly used fixation plates. The results of measured strains at each location show a very high correlation between the physical model and the virtual mandible of their biomechanical behaviors under simulated occlusal loading conditions when treating angle fracture of the mandible., Conclusions: Based on the results from our study, we validate the accuracy of our computational model which allows us to use it for future clinical applications under more sophisticated biomechanical simulations and testing.

Background: Severe acute pancreatitis (SAP) is characterized by the noxious combination of severe systemic inflammation and hypoperfusion and oxidative stress. Ischemia-modified albumin (IMA) was recognized as a novel marker of oxidative stress and ischemia. The purpose of this study was to evaluate serum IMA level in patients with SAP and analyze its prognostic significance. Methods: A total of 72 patients with SAP were enrolled. Serum IMA level was measured within 24 hours of the onset of SAP, and baseline characteristics were recorded. The BISAP, APACHE II and SOFA scores were calculated. Multivariate logistic regression and receiver operating characteristic curve analyses were used to evaluate predictive ability of LMA for in-hospital mortality of SAP. Kaplan-Meier analysis was further used to compare in-hospital mortality difference between high LMA and low LMA. Results: The overall in-hospital mortality rate of all 72 SAP patients was 23.6%. Non-survivor group had higher serum IMA (107.2±10.8 VS 88.4±11.9, P<0.05) than survivor group. Otherwise, the optimal cutoff levels for the IMA predicting in-hospital mortality of patients with SAP was 112 U/ml using a sensitivity of 77.4% and a specificity of 76.2% as optimal conditions (AUC, 0.734; 95% CI: 0.615-0.852; P=0.002). IMA level also was confirmed as an independent prognostic factor for SAP in multivariate analysis. Patient with high IMA level (≥112 U/ml) had poorer survival rate than low IMA (<112 U/ml) in log-rank test of Kaplan-Meier survival analysis (P<0.05). Conclusions: Serum IMA level can be considered as an independent predictor for in-hospital mortality of patients with SAP., Competing Interests: None., (IJCEP Copyright © 2017.)

Physiologically based in vitro methods have been developed to measure bioaccessibility of organic contaminants in soils. However, bioaccessibility of hydrophobic organic contaminants (HOCs) can be underestimated by in vitro tests if gastrointestinal (GI) solution fails to provide sufficient sorption sink for HOCs. To circumvent this drawback, Tenax was included in GI solution as sorption sink to trap mobilized HOCs and maintain the desorption gradient between soil and GI solution. Polycyclic aromatic hydrocarbons (PAHs) were selected as target HOCs, and physiologically based extraction test (PBET) was selected as the in vitro method. Inclusion of Tenax in GI solution increased bioaccessibility of PAHs in five spiked soils from 8.25-20.8% to 55.7-65.9% and the bioaccessibility of PAHs in a field contaminated soil from 3.70-6.92% to 16.3-31.0%. Our results demonstrated the effectiveness of Tenax as sorption sink to enhance PAH mobilization in bioaccessibility measurement in soils., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objective: We conducted a case-control study by genotyping three potential functional SNPs to assess the association of Xeroderma pigmentosum complementation group F (XPF) polymorphisms with gastric cancer susceptibility, and role of XPF polymorphisms in combination with H.pylori infection in the risk of gastric cancer., Methodology: A hospital case-control study was conducted. A total of 331 patients with gastric cancer and 355 controls were collected. Three SNPs of XPF, XPF rs180067, rs1799801 and rs2276466, were genotyped by Taqman real-time PCR method with a 7900 HT sequence detector system., Results: The gastric cancer patients were more likely to have smoking habit, a family history of cancer and H.pylori infection. We did not find the significant difference in the genotype distributions of XPF rs180067, rs1799801 and rs2276466 between cases and controls. Multivariate logistic analysis showed a non-significant decreased risk in patients carrying rs180067 G allele, rs1799801 T allele or rs2276466 T allele genotypes. The stratification by H.pylori infection was not significantly different in polymorphisms of XPF rs180067, rs1799801 and rs2276466., Conclusion: There was no evidence that polymorphisms in rs180067, rs1799801 and rs2276466 significantly affect the risk of gastric cancer. Further large sample size studies are strongly needed to validate their association.

Objective: To determine the prevalence of dietary problems in children 1-6 years old in Chengdu., Methods: A cross-sectional survey was undertaken in Chengdu. Five child care facilities were randomly selected. All of the children attending those facilities were surveyed using a structured questionnaire containing questions about socio-economic situation and dietary behaviors of the children and nutritional knowledge of their caregivers. This resulted in 1421 respondents., Results: Some 38.63% of children had at least one dietary problem. Strong preference for a small range of foods accounted for 27.23% of all dietary problems., Conclusion: Dietary problems in children of 1-6 year are common in Chengdu. Parents should be educated and play a more important role in the prevention and intervention of dietary problems in children.

Objective: To develop a new high-performance liquid chromatographic (HLPC) method for determination of propofol in human serum., Methods: Human serum samples were precipitated with 20% perchloric acid and centrifuged to obtain 50 microl of the supernatant for analysis by HPLC coupled with fluorescence detection. The analysis was performed with a C(18) reversed-phase column using a acetonitrile-water (90:10) phase delivered at 1.0 ml/min, with the excitation wavelength of 276 nm and emission wavelength of 310 nm., Results: The calibration curves were linear (r=0.997 5) within the concentration range of 0.05-10 microg/ml, the limit of propofol quantification was 50 ng/ml and the intra- and inter-day precisions were between -/+15%., Conclusions: The method is accurate, sensitive and simple for propofol determination in clinical anesthesia.