Abstract Objective To explore the molecular mechanism of neuropathologic damage induced by radiofrequency ablation at different temperatures. Methods This is basic research, and 36 SD rats were used to construct the neuropathological injury model. The rats were subjected to radiofrequency stimulation at different temperatures and were divided into 6 groups according to the temperature injury: 42°, 47°, 52°, 57°, 62°, and 67°C groups. Conduction time, conduction distance, and nerve conduction velocity were recorded after temperature injury. HE-staining was used to observe the histopathological morphology of the sciatic nerve. The expression of SCN9A, SCN3B, and NFASC protein in sciatic nerve tissue were detected by western blot. Results With the increase in temperature, nerve conduction velocity gradually decreased, and neurons were damaged when the temperature was 67°C. HE-staining showed that the degrees of degeneration of neurons in rats at 47°, 52°, 57°, 62°, and 67°C were gradually increased. The expression of SCN9A, SCN3B protein in 57°, 62°, 67°C groups were much higher than that of NC, 42°, 47°, 52°C groups. However, the expression of NFASC protein in 57°, 62°, 67°C groups was much lower than that of the NC, 42°, 47°, 52°C groups. Conclusion There was a positive correlation between temperature caused by the radiofrequency stimulation to neuropathological damage. The mechanism is closely related to the expression of SCN9A, SCN3B, and NFASC protein in nerve tissue caused by heat transfer injury.

Abstract Active suspension is considered to be a good way to improve the ride comfort of high-speed trains. According to the output index requirements of train’s active suspension, a giant magnetostrictive actuator(GMA) is proposed. This is mainly because giant magnetostrictive materials(GMM) has the characteristics of fast response, large output force and high energy conversion rate. It is verified by experiments that the output force is proportional to the excitation current. It is found in the experiment that the excitation frequency should be greater than 120Hz to obtain a stable output force, and it is also found that preload and excitation frequency will affect response time. On the basis of experiments, a 2-DOF physical and mathematical model of the vertical quarter train is built. An MPC algorithm is designed to control GMA active suspension. Through simulation analysis, the proposed control algorithm is compared with passive suspension and active suspension based on PID control algorithm. Both theory and practice show that the proposed control algorithm is effective.

OBJECTIVES: Osteoporotic vertebral compression fractures (OVCFs) affect the elderly population, especially postmenopausal women. Percutaneous kyphoplasty is designed to treat painful vertebral compression fractures for which conservative therapy has been unsuccessful. High-viscosity cement can be injected by either a hydraulic pressure delivery system (HPDS) or a balloon tamp system (BTS). Therefore, the purpose of this study was to compare the safety and clinical outcomes of these two systems. METHODS: A random, multicenter, prospective study was performed. Clinical and radiological assessments were carried out, including assessments of general surgery information, visual analog scale, quality of life, cement leakage, and height and angle restoration. RESULTS: Using either the HPDS or BTS to inject high-viscosity cement effectively relieved pain and improved the patients’ quality of life immediately, and these effects lasted at least two years. The HPDS using high-viscosity cement reduced cost, surgery time, and radiation exposure and showed similar clinical results to those of the BTS. In addition, the leakage rate and the incidence of adjacent vertebral fractures after the HPDS treatment were reduced compared with those after treatment using the classic vertebroplasty devices. However, the BTS had better height and angle restoration abilities. CONCLUSIONS: The percutaneous HPDS with high-viscosity cement has similar clinical outcomes to those of traditional procedures in the treatment of vertebral fractures in the elderly. The HPDS with high-viscosity cement is better than the BTS in the treatment of mild and moderate OVCFs and could be an alternative method for the treatment of severe OVCFs.

Abstract Purpose: To investigate the influence of dexmedetomidine on myocardial ischemia-reperfusion injury (IRI) in rabbits. Methods: Twenty-four New Zealand white rabbits were randomly divided into two equal-sized groups: IRI group (group IR) and dexmedetomidine group (group D). Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), left ventricular diastolic pressure (LVDP), +dp/dtmax, -dp/dtmax, and t-dp/dtmax were recorded and calculated at the following time points: before (T0) and after (T1) dexmedetomidine infusion, after 30-min ischemia (T2), and after 120-min reperfusion (T3). The levels of plasma endothelin 1 (ET-1), thromboxane A2 (TXA2), and platelet activating factor (PAF); area of myocardial infarction (MI); and no-reflow area were evaluated. Results: SBP, DBP, LVSP, LVEDP, LVDP, and +dp/dtmax at T3 were higher in group D than in group IR (P<0.05). The average no-reflow area in group IR was significantly smaller than that in group D (14±3% vs. 38±5%, P=0.0116). The ET-1, TXA2, and PAF levels at T2 and T3 were higher than those at T0 in both groups (P<0.05). Conclusion: Dexmedetomidine could reduce the magnitude of ischemic myocardial no-reflow area and protect the myocardium with ischemia-reperfusion injury.

ABSTRACT The spoilage of beer by bacteria is of great concern to the brewer as this can lead to turbidity and abnormal flavors. The polymerase chain reaction (PCR) method for detection of beer-spoilage bacteria is highly specific and provides results much faster than traditional microbiology techniques. However, one of the drawbacks is the inability to differentiate between live and dead cells. In this paper, the combination of propidium monoazide (PMA) pretreatment and conventional PCR had been described. The established PMA-PCR identified beer spoilage Lactobacillus brevis based not on their identity, but on the presence of horA gene which we show to be highly correlated with the ability of beer spoilage LAB to grow in beer. The results suggested that the use of 30 µg/mL or less of PMA did not inhibit the PCR amplification of DNA derived from viable L. brevis cells. The minimum amount of PMA to completely inhibit the PCR amplification of DNA derived from dead L. brevis cells was 2.0 µg/mL. The detection limit of PMA-PCR assay described here was found to be 10 colony forming units (CFU)/reaction for the horA gene. Moreover, the horA-specific PMA-PCR assays were subjected to 18 reference isolates, representing 100% specificity with no false positive amplification observed. Overall the use of horA-specific PMA-PCR allows for a substantial reduction in the time required for detection of potential beer spoilage L. brevis and efficiently differentiates between viable and nonviable cells.