Biomechanical evaluation on a new type of vertebral titanium porous mini-plate and mechanical comparison between cervical open-door laminoplasty and laminectomy: a finite element analysis.

Objective: Compare the spine's stability after laminectomy (LN) and laminoplasty (LP) for two posterior surgeries. Simultaneously, design a new vertebral titanium porous mini plate (TPMP) to achieve firm fixation of the open-door vertebral LP fully. The objective is to enhance the fixation stability, effectively prevent the possibility of "re-closure," and may facilitate bone healing. Methods: TPMP was designed by incorporating a fusion body and porous structures, and a three-dimensional finite element cervical model of C2-T1 was constructed and validated. Load LN and LP finite element models, respectively, and analyze and simulate the detailed processes of the two surgeries. It was simultaneously implanting the TPMP into LP to evaluate its biomechanical properties. Results: We find that the range of motion (ROM) of C4-C5 after LN surgery was greater than that of LP implanted with different plates alone. Furthermore, flexion-extension, lateral bending, and axial rotation reflect this change. More noteworthy is that LN has a much larger ROM on C2-C3 in axial rotation. The ROM of LP implanted with two different plates is similar. There is almost no difference in facet joint stress in lateral bending. The facet joint stress of LN is smaller on C2-C3 and C4-C5, and larger more prominent on C5-C6 in the flexion-extension. Regarding intervertebral disc pressure (IDP), there is little difference between different surgeries except for the LN on C2-C3 in axial rotation. The plate displacement specificity does not significantly differ from LP with vertebral titanium mini-plate (TMP) and LP with TPMP after surgery. The stress of LP with TPMP is larger in C4-C5, C5-C6. Moreover, LP with TMP shows greater stress in the C3-C4 during flexion-extension and lateral bending. Conclusion: LP may have better postoperative stability when posterior approach surgery is used to treat CSM; at the same time, the new type of vertebral titanium mini-plate can achieve almost the same effect as the traditional titanium mini-plate after surgery for LP. In addition, it has specific potential due to the porous structure promoting bone fusion.

Thermal and Chemical Inactivation of Bacillus Phage BM-P1.

Bacillus spp. are often used as probiotics; however, they can be infected by phages, leading to significant economic losses. Biocidal and thermal treatments are considered rapid and effective methods for controlling microbial contamination. To prevent viral contamination in industrial dairy production, the impact of temperature and biocides on the viability of Bacillus methylotrophic phage BM-P1 was assessed. The results demonstrated that reconstituted skim milk (RSM) as a medium showed the most effective protective effect on phage BM-P1. Treatment at 90°C for 5 min or 72°C for 10 min inactivated it to nondetectable levels from the initial titer of 7.19 ± 0.11 log, regardless of the culture medium. Sodium hypochlorite exhibited the best inactivating effect, which could reduce the phage titer below the detection level in 4 min at 50 ppm. Additionally, treatment with 75% ethanol for 20 min or 50% isopropanol for 30 min could achieve inactivation to nondetectable levels. The inactivating effect of peracetic acid was limited; even when treated at the highest concentration (0.45%) for 60 min, only a 2.47 ± 0.17 log reduction was observed. This study may provide some theoretical basis and data support for establishing measures against Bacillus spp. phages.

Comparison of biomechanical parameters of two Chinese cervical spine rotation manipulations based on motion capture and finite element analysis.

Objective: The purpose of this study was to obtain the stress-strain of the cervical spine structure during the simulated manipulation of the oblique pulling manipulation and the cervical rotation-traction manipulation in order to compare the mechanical mechanism of the two manipulations. Methods: A motion capture system was used to record the key kinematic parameters of operating the two manipulations. At the same time, a three-dimensional finite element model of the C0-T1 full healthy cervical spine was established, and the key kinematic parameters were loaded onto the finite element model in steps to analyze and simulate the detailed process of the operation of the two manipulations. Results: A detailed finite element model of the whole cervical spine including spinal nerve roots was established, and the validity of this 3D finite element model was verified. During the stepwise simulation of the two cervical spine rotation manipulations to the right, the disc (including the annulus fibrosus and nucleus pulposus) and facet joints stresses and displacements were greater in the oblique pulling manipulation group than in the cervical rotation-traction manipulation group, while the spinal cord and nerve root stresses were greater in the cervical rotation-traction manipulation group than in the oblique pulling manipulation group. The spinal cord and nerve root stresses in the cervical rotation-traction manipulation group were mainly concentrated in the C4/5 and C5/6 segments. Conclusion: The oblique pulling manipulation may be more appropriate for the treatment of cervical spondylotic radiculopathy, while cervical rotation-traction manipulation is more appropriate for the treatment of cervical spondylosis of cervical type. Clinicians should select cervical rotation manipulations for different types of cervical spondylosis according to the patient's symptoms and needs.

Plasma Polishing as a New Polishing Option to Reduce the Surface Roughness of Porous Titanium Alloy for 3D Printing.

Porous titanium alloy implants with simulated trabecular bone fabricated by 3D printing technology have broad prospects. However, due to the fact that some powder adheres to the surface of the workpiece during the manufacturing process, the surface roughness in direct printing pieces is relatively high. At the same time, since the internal pores of the porous structure cannot be polished by conventional mechanical polishing, an alternative method needs to be found. As a surface technology, plasma polishing technology is especially suitable for parts with complex shapes that are difficult to polish mechanically. It can effectively remove particles and fine splash residues attached to the surface of 3D printed porous titanium alloy workpieces. Therefore, it can reduce surface roughness. Firstly, titanium alloy powder is used to print the porous structure of the simulated trabecular bone with a metal 3D printer. After printing, heat treatment, removal of the supporting structure, and ultrasonic cleaning is carried out. Then, plasma polishing is performed, consisting of adding a polishing electrolyte with the pH set to 5.7, preheating the machine to 101.6 °C, fixing the workpiece on the polishing fixture, and setting the voltage (313 V), current (59 A), and polishing time (3 min). After polishing, the surface of the porous titanium alloy workpiece is analyzed by a confocal microscope, and the surface roughness is measured. Scanning electron microscopy is used to characterize the surface condition of porous titanium. The results show that the surface roughness of the whole porous titanium alloy workpiece changed from Ra (average roughness) = 126.9 µm to Ra = 56.28 µm, and the surface roughness of the trabecular structure changed from Ra = 42.61 µm to Ra = 26.25 µm. Meanwhile, semi-molten powders and ablative oxide layers are removed, and surface quality is improved.

In silico biomechanical analysis of poller screw-assisted small-diameter intramedullary nail in the treatment of distal tibial fractures.

Objective: To evaluate the biomechanical effects of Poller screws (PS) combined with small-diameter intramedullary nails in the treatment of distal tibial fractures at different locations and on different planes. Methods: Nine finite element (FE) models were used to simulate the placement of the intramedullary nail (IMN) and the PS for distal tibial fractures. Structural stiffness and interfragmentary motion (IFM) through the fracture were investigated to assess the biomechanical effects of the PS. The allowable stress method was used to evaluate the safety of the construct. Results: With the axial load of 500 N, the mean axial stiffness of IMN group was 973.38 ± 95.65 N/mm, which was smaller than that at positions A and B of the coronal group and sagittal group (p < 0.05). The shear IFM of the IMN group was 2.10 ± 0.02 mm, which were smaller than that at positions A and B of the coronal group and sagittal group (p < 0.05). Under physiological load, the stresses of all internal fixation devices and the nail-bone interface were within a safe range. Conclusion: In the treatment of distal tibial fractures, placing the PS in the proximal fracture block can obtain better biomechanical performance. The IMN fixation system can obtain higher structural stiffness and reduce the IFM of the fracture end by adding PS.

Changes in the gut microbiota structure and function in rats with doxorubicin-induced heart failure.

Objectives: The rat model of heart failure (HF) induced by doxorubicin (DOX), a broad spectrum and highly effective chemotherapeutic anthracycline with high-affinity to myocardial tissue that causes severe dose-dependent irreversible cardiotoxicity has been widely recognized and applied in HF pathogenesis and drug therapy studies. The gut microbiota (GM) has attracted significant attention due to its potential role in HF, and research in this area may provide beneficial therapeutic strategies for HF. Considering the differences in the route, mode, and total cumulative dose of DOX administration used to establish HF models, the optimal scheme for studying the correlation between GM and HF pathogenesis remains to be determined. Therefore, focusing on establishing the optimal scheme, we evaluated the correlation between GM composition/function and DOX-induced cardiotoxicity (DIC). Methods: Three schemes were investigated: DOX (at total cumulative doses of 12, 15 or 18 mg/kg using a fixed or alternating dose via a tail vein or intraperitoneal injection) was administered to Sprague Dawley (SD) for six consecutive weeks. The M-mode echocardiograms performed cardiac function evaluation. Pathological changes in the intestine were observed by H&E staining and in the heart by Masson staining. The serum levels of N-terminal pre-B-type natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI) were measured by ELISA. The GM was analysed by 16S rRNA gene sequencing. Key findings: Strikingly, based on the severity of cardiac dysfunction, there were marked differences in the abundance and grouping of GM under different schemes. The HF model established by tail vein injection of DOX (18 mg/kg, alternating doses) was more stable; moreover, the degree of myocardial injury and microbial composition were more consistent with the clinical manifestations of HF. Conclusions: The model of HF established by tail vein injection of doxorubicin, administered at 4mg/kg body weight (2mL/kg) at weeks 1, 3 and 5, and at 2mg/kg body weight (1mL/kg) at weeks 2, 4 and 6, with a cumulative total dose of 18mg/kg, is a better protocol to study the correlation between HF and GM.

Inactivation of Lactobacillus Bacteriophages by Dual Chemical Treatments.

Phage contamination is one of the significant problems in the food fermentation industry, which eventually causes economic losses to the industry. Here, we investigated the viability of Lactobacillus plantarum phage P1 and P2 using various biocides treatments (ethanol, isopropanol, sodium hypochlorite and peracetic acid). Results indicated that phage P1 and P2 could be completely inactivated by treatment with 75% ethanol for 5 min, followed by 400 ppm of sodium hypochlorite treatment for 5 min. Phage P2 could be completely inactivated in the reverse sequence, while 800 ppm of sodium hypochlorite was required to achieve a similar effect for phage P1. Moreover, 100% isopropanol could increase the inactivating effect of 75% ethanol. This study may provide basic information on using multiple antimicrobials for phage control in laboratories and food plants.

Efficacy and Safety of Evolocumab in Chinese Patients with Primary Hypercholesterolemia and Mixed Dyslipidemia: 12-Week Primary Results of the HUA TUO Randomized Clinical Trial.

INTRODUCTION: Evolocumab, a fully human proprotein convertase/subtilisin kexin type 9 inhibitor antibody, significantly lowers low-density lipoprotein cholesterol (LDL-C) in patients with type 2 diabetes mellitus and hyperlipidemia and mixed dyslipidemia. This 12-week study evaluated the efficacy and safety of evolocumab in Chinese patients with primary hypercholesterolemia and mixed dyslipidemia at different levels of cardiovascular disease risk. METHODS: HUA TUO was a 12-week randomized, double-blind, placebo-controlled study. Chinese patients aged 18 years or older on stable optimized statin therapy were randomized 2:2:1:1 to receive evolocumab 140 mg every 2 weeks (Q2W), evolocumab 420 mg monthly (QM), or a matching placebo. The coprimary endpoints were percent change from baseline in LDL-C at the mean of weeks 10 and 12 and at week 12. RESULTS: Overall, 241 randomized patients (mean [standard deviation] age, 60.2 [10.3] years) received evolocumab 140 mg Q2W (n = 79), evolocumab 420 mg QM (n = 80), placebo Q2W (n = 41), or placebo QM (n = 41). At weeks 10 and 12, the placebo-adjusted least-squares mean percent change from baseline in LDL-C for the evolocumab 140 mg Q2W group was - 70.7% (95% CI - 78.0% to - 63.5%); - 69.7% (95% CI - 76.5% to - 63.0%) for the evolocumab 420 mg QM group. Significant improvements in all other lipid parameters were observed with evolocumab. The patient incidence of treatment-emergent adverse events was similar between the treatment groups and across dosing regimens. CONCLUSION: In Chinese patients with primary hypercholesterolemia and mixed dyslipidemia, 12-week treatment with evolocumab significantly lowered LDL-C and other lipids, and was safe and well tolerated (NCT03433755).

Investigating the mechanical effect of the sagittal angle of the cervical facet joint on the cervical intervertebral disc.

Background: Facet tropism is defined as the asymmetry between the left and right facet joints relative to the sagittal plane. Published clinical studies have found that facet tropism is associated with cervical disc herniation. However, the relationship between the facet orientation and the side of cervical disc herniation remains controversial. Therefore, this study used the finite-element technique to investigate the biomechanical effects of the sagittal angle of the cervical facet joints on the cervical intervertebral disc. Objective: The biomechanical effects of the sagittal angle of the cervical facet joint on the cervical disc and facet joint were investigated using the finite-element technique. Methods: The finite-element model was constructed using computed tomography scans of a 26-year-old female volunteer. First, a cervical model was constructed from C3 to C7. The model was verified using data from previously published studies. Second, the facet orientation at the C5-C6 level was altered to simulate different sagittal angles of cervical facet joints. Five models, F70, F80, F90, F100, and F110, were simulated with different facet joint orientations (70°, 80°, 90°, 100°, and 110° facet joint angles at the left side, respectively, and 90° facet joint angles at the right side) at the C5-C6 facet joints. In each model, annular fibres stress and facet cartilage pressure were studied under six pure moments and two combined moments. Results: Comparing the stress of the annulus fibres in flexion combined with right axial rotation and in flexion combined with left axial rotation in the same model, no difference in the maximum stress of the annulus fibres was noted between these two different moments in the F90 model, whereas differences of 12.80%, 8.84%, 14.95% and 33.32% were noted in the F70, F80, F100 and F110 models, respectively. The same trend was observed when comparing the maximum stress of the annulus fibres in each model during left and right axial rotation. No differences in annular fibres stress and facet cartilage pressure were noted among the five models in flexion, extension, lateral bending, left axial rotation, and flexion combined with left axial rotation in this study. However, compared with the F70 model in flexion combined with right axial rotation, the annulus fibres stress of the F80, F90, F100, and F110 models increased by 5.53%, 13.03%, 35.04%, and 72.94%, respectively, and the pressure of the left facet joint of these models decreased by 5.65%, 12.10%, 18.41%, and 25.74%, respectively. The same trend was observed in the right axial moment. Conclusion: Facet tropism leads to unbalanced stress distribution on the annulus fibres at the cervical intervertebral disc. The greater the sagittal angle of the facet joint, the greater the annular fibres stress on this side. We hypothesised that the side with the larger sagittal angle of the facet joint exhibits a greater risk of disc herniation.

Mechanical Parameters and Trajectory of Two Chinese Cervical Manipulations Compared by a Motion Capture System.

Objective: To compare the mechanical parameters and trajectory while operating the oblique pulling manipulation and the cervical rotation-traction manipulation. Methods: An experimental research measuring kinematics parameter and recording motion trajectories of two cervical manipulations were carried out. A total of 48 healthy volunteers participated in this study, who were randomly divided into two groups of 24 representing each of the two manipulations. A clinician performed two manipulations in two groups separately. A motion capture system was used to monitor and analyze kinematics parameters during the operation. Results: The two cervical manipulations have similar thrust time, displacement, mean velocity, max velocity, and max acceleration. There were no significant differences in active and passive amplitudes between the two cervical rotation manipulations. The thrust amplitudes of the oblique pulling manipulation and the cervical rotation-traction manipulation were 5.735 ± 3.041° and 2.142 ± 1.742°, respectively. The thrust amplitudes of the oblique pulling manipulation was significantly greater than that of the cervical rotation-traction manipulation (P < 0.001). Conclusion: Compared with the oblique pulling manipulation, the cervical rotation-traction manipulation has a less thrust amplitudes.

Rupture Risk Assessment of Cervical Spinal Manipulations on Carotid Atherosclerotic Plaque by a 3D Fluid-Structure Interaction Model.

METHOD: The FSI model, based on MRI data of an atherosclerosis patient, was used to simulate the deformations of the plaque and lumen during the process of two kinds of typical cSMT (the high-speed, low-amplitude spinal manipulation and the cervical rotatory manipulation). The biomechanical parameters were recorded, such as the highest wall shear stress (WSS), the maximum plaque wall stress (PWS), the wall tensile stress (Von mises stress, VWTS), and the strain. RESULT: The max_WSS was 33.77 kPa in the most extensive deformation. The highest WSS region on the plaque surface was also the highest PWS region. The max_PWS in a 12% stretch was 55.11 kPa, which was lower than the rupture threshold. The max_VWTS of the cap in 12% stretch which approached the fracture stress level was 116.75 kPa. Moreover, the vessel's max_VWTS values in 10% and 12% stretch were 554.21 and 855.19 kPa. They were higher than the fracture threshold, which might cause media fracture. Meanwhile, the 7% stretched strain was 0.29, closed to the smallest experimental green strains at rupture. CONCLUSION: The carotid arteries' higher stretch generated the higher stress level of the plaque. Cervical rotatory manipulation might cause plaque at a high risk of rupture in deformation after 12% stretch and more. Lower deformation of the plaque and artery caused by the high-speed, low-amplitude spinal manipulation might be safer.

The relationship between facet tropism and cervical disc herniation.

Many studies have demonstrated the association between facet tropism and disc herniation in the lumbar spine. Some of them found that lumbar disc herniation was on the side of the more sagittal facet joint interface. However, little is understood about the association of facet tropism with disc herniation in the cervical spine. As the relationship between the facet orientation and the side of cervical disc herniation (CDH) is unclear, the purpose of this study is to investigate that relationship. Ninety-six patients with single-level CDH (C4-C5, C5-C6 or C6-C7) were included in the CDH group of this study. Another 50 age-matched and gender-matched healthy participants who accepted physical examinations were enrolled as the control group. The cervical facet angles of two sides were measured using axial computed tomography (CT). The intersection angle of the midsagittal line of the vertebra to the facet line represents the facet angle. Facet tropism was defined as the angular difference of 7º between the left and the right sides. Facet tropism angle was recorded as the absolute value of the difference of facet angles between two sides. There were 20 herniations at C4-C5 level, 50 herniations at C5-C6 level and 26 herniations at C6-C7 level. The present study showed that more cases in the CDH group had facet tropism than did those in the control group at C4-C5, C5-C6 and C6-C7 level (p = .021, p = .001, p = .015, respectively). The facet tropism angles in the CDH group were significantly bigger than those in the control group at C4-C5, C5-C6 and C6-C7 level (p = .001, p = .002, p = .028, respectively). In the CDH group, the facet angles on the herniated side were found to be significantly bigger than those on the healthy side at C4-C5, C5-C6 and C6-C7 level (p = .000, p = .000, p = .037, respectively). The findings of this present study suggest that facet tropism is associated with the disc herniation in the cervical spine. We also found that cervical disc herniates towards the side of the bigger facet angle with respect to the sagittal plane. There is a need for future studies to verify the biomechanical impact of facet tropism on CDH.

Application value of hypersensitive C-reactive protein, lactic acid and myoglobin in the combined detection of myocarditis.

Application value of hypersensitive C-reactive protein (hs-CRP), blood lactic acid (LAC) and myoglobin (Mb) in the combined detection of myocarditis was explored. A total of 107 patients with suspected myocarditis treated in The Second Nanning People's Hospital from January 2015 to December 2017 were retrospectively analyzed, of whom 81 patients diagnosed with myocarditis were enrolled into the research group, and 26 non-myocarditis individuals were enrolled into the control group. Fasting venous blood was drawn from all patients to detect the hs-CRP, LAC and Mb, and their levels were compared and analyzed between the two groups. Moreover, the coincidence rate, sensitivity and specificity of single detection and combined detection by hs-CRP, LAC and Mb in the diagnosis of myocarditis were compared and analyzed. There were no significant differences in the sex, age, smoking status, alcohol consumption, chest distress, palpitation, angina and dyspnea between the two groups (P>0.05), proving that patients in both groups were comparable. The levels of hs-CRP, LAC and Mb in the research group were significantly higher than those in the control group, displaying statistically significant differences (P<0.05). According to the receiver operating characteristic (ROC) curve, the area under the curve (AUC), coincidence rate, sensitivity and specificity in the diagnosis of myocarditis, respectively, were 0.610 (95% CI: 0.495-0.725), 58.88, 51.85 and 80.77% for hs-CRP, 0.657 (95% CI: 0.551-0.763), 58.88, 54.32 and 73.08% for LAC, 0.747 (95% CI: 0.651-0.843), 69.16, 64.20 and 84.62% for Mb, and 0.773 (95% CI: 0.680-0.867), 76.64, 79.01 and 69.23% for combined detection. Hs-CRP, LAC and Mb are highly expressed in the serum of patients with myocarditis, and their combined detection has guiding significance for the prevention and treatment of myocarditis.

STAT3-induced upregulation of lncRNA MEG3 regulates the growth of cardiac hypertrophy through miR-361-5p/HDAC9 axis.

Cardiac hypertrophy is closely correlated with diverse cardiovascular diseases, augmenting the risk of heart failure and sudden death. Long non-coding RNAs (lncRNAs) have been studied in cardiac hypertrophy for their regulatory function. LncRNA MEG3 has been reported in human cancers. Whereas, it is unknown whether MEG3 regulates the growth of cardiac hypertrophy. Therefore, this study aims to investigate the specific role of MEG3 in the progression of cardiac hypertrophy. Here, we found that MEG3 contributed to the pathogenesis of cardiac hypertrophy. MEG3 expression was remarkably strengthened in the mice heart which undergone the transverse aortic constriction (TAC). Moreover, qRT-PCR analysis revealed that MEG3 was upregulated in the cardiomyocytes which were treated with Ang-II. Silenced MEG3 inhibited the increasing size of hypertrophic cardiomyocytes and reversed other hypertrophic responses. Mechanically, MEG3 could affect cardiac hypertrophy by regulating gene expression. Mechanically, we found that MEG3 could be upregulated by the transcription factor STAT3 and could regulate miR-361-5p and HDAC9 by acting as a ceRNA. Finally, rescue assays were made to do further confirmation. All our findings revealed that STAT3-inducetd upregulation of lncRNA MEG3 controls cardiac hypertrophy by regulating miR-362-5p/HDAC9 axis.

Protective effects and mechanism of curcumin on myocardial injury induced by coronary microembolization.

OBJECTIVE: Coronary microembolization (CME) is a common complication during the percutaneous coronary intervention (PCI). CME-induced local myocardial inflammation and myocardial apoptosis are the primary causes of progressive cardiac dysfunction. Curcumin exerts a protective role in various cardiovascular diseases; however, its effects in CME are yet to be clarified. Therefore, the current study investigated the effects of curcumin on myocardial inflammatory responses, myocardial apoptosis, and cardiac dysfunctions induced by CME in rats. METHODS: A total of 40 Sprague-Dawley rats were randomly divided into the following groups: Sham operation (sham group), CME group, curcumin, and control with 10 rats in each group. The ascending aortas were clamped, and the CME-model group was established by injecting microspheres into the apex of the left ventricle. An equivalent amount of normal saline was injected to establish the sham group. The cardiac functions, serum c-troponin I level, and apoptotic index was examined. Also, the levels of Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MYD88), nuclear factor κB (NF-κB) p65, BCL2-associated X protein (Bax), B-cell lymphoma 2 (Bcl-2), cleaved caspase-3, tumor necrosis factor α (TNF-α), and interleukin-1ß (IL-1ß) were detected. RESULTS: Myocardial dysfunction enhanced serum c-troponin I, and apoptotic index were induced following CME. Moreover, CME elevated the expression of TLR4, MyD88, NF-κB p65, cleaved caspase-3, TNF-α, and IL-1ß, while the Bcl-2/Bax ratio decreased. Curcumin reversed these effects by CME, while the gastric lavage control did not exert any effect. CONCLUSION: Curcumin was responsible for the anti-CME-induced myocardial injury. The effector mechanism might be related to the reduction of cardiomyocyte apoptosis and inhibition of myocardial inflammatory responses mediated by TLR4/MyD88/NF-κB signaling pathway.

Biomechanical Effects of Lateral Bending Position on Performing Cervical Spinal Manipulation for Cervical Disc Herniation: A Three-Dimensional Finite Element Analysis.

BACKGROUND: Most studies report that the common position of cervical spinal manipulation (CSM) for treating symptomatic cervical disc herniation (CDH) is lateral bending to the herniated side. However, the rationality of lateral bending position on performing CSM for CDH is still unclear. OBJECTIVE: The purpose of this study is to investigate the biomechanical effects of lateral bending position on performing CSM for CDH. METHODS: A finite element (FE) model of CDH (herniated on the left side) was generated in C5-6 segment based on the normal FE model. The FE model performed CSM in left lateral bending position, neutral position, and right lateral bending position, respectively. Cervical disc displacement, annulus fiber stress, and facet joint stress were observed during the simulation of CSM. RESULTS: The cervical disc displacement on herniated side moved forward during CSM, and the maximum forward displacements were 0.23, 0.36, and 0.45 mm in left lateral bending position, neutral position, and right lateral bending position, respectively. As the same trend of cervical disc displacement, the annulus fiber stresses on herniated side from small to large were 7.40, 16.39, and 22.75 MPa in left lateral bending position, neutral position, and right lateral bending position, respectively. However, the maximum facet stresses at left superior cartilage of C6 in left lateral bending position, neutral position, and right lateral bending position were 6.88, 3.60, and 0.12 MPa, respectively. CONCLUSION: Compared with neutral position and right lateral bending position, though the forward displacement of cervical disc on herniated side was smaller in left lateral bending position, the annulus fiber stress on herniated side was declined by sharing load on the left facet joint. The results suggested that lateral bending to the herniated side on performing CSM tends to protect the cervical disc on herniated side. Future clinical studies are needed to verify that.

Risk factors for recollapse of the augmented vertebrae after percutaneous vertebroplasty for osteoporotic vertebral fractures with intravertebral vacuum cleft.

To determine risk factors related to recollapse of the augmented vertebrae after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs) with intravertebral vacuum cleft (IVC).Fifty-two patients treated with PVP for single OVCFs with the IVC were retrospectively reviewed. The follow-up period was at least 2 years. Vertebral height loss ≥15% or kyphotic angle ≥10° at the final follow-up in relation to the immediately postoperative values were adopted as a definition of recollapse of the augmented vertebrae. Correlation analysis and multiple logistic regression analyses were performed to elucidate the related clinical or radiological factors for recollapse of the augmented vertebrae including age, gender, bone mineral density, preoperative fracture severity, locations of IVC sign, distribution patterns of polymethylmethacrylate (PMMA), reduction rate, and reduction angle.Assuming the increase of height loss more than 15% as a criterion of recollapse, only cleft filling pattern of PMMA in the IVC area was a significant risk factor for recollapse of the augmented vertebrae (P < 0.01). Assuming ≥10° progression of kyphotic angle as a criterion, cleft filling pattern of PMMA and higher values of reduction angle was as 2 significant risk factors for recollapse of the augmented vertebrae (P < 0.01). No significant difference was found in other clinical and radiological factors (P > 0.05).Cleft filling pattern of PMMA and higher values of reduction angle may play an important role in inducing recollapse of the augmented vertebrae after PVP for OVCFs with the IVC. Careful observation of patients with these conditions is necessary to prevent deterioration of their clinical course.

[Effect of intensive pretreatment with atorvastatin calcium on outcomes of percutaneous coronary intervention in elderly patients with coronary heart disease].

OBJECTIVE: To observe the effects of different loading doses of atorvastatin calcium on the outcomes of percutaneous coronary intervention (PCI) in elderly patients with coronary heart disease (CHD). METHODS: A total of 120 CHD patients aged over 80 years were randomly assigned into 3 equal groups to receive intensive pretreatment with statin at the doses of 20, 40, or 60 mg prior to PCI performed within 48 to 72 h after admission. The changes of postoperative cardiac biochemical markers including creatine kinase isoenzyme (CKMB), troponin I (cTNI) and high-sensitivity c-reactive protein (hs-CRP) were observed and the incidence of major adverse cardiac events (MACE, including cardiac death, myocardial infarction, and target vessel revascularization) were recorded within 30 days after PCI. RESULTS: Thirty-four patients in 20 mg statin group, 40 in 40 mg statin group, and 38 in 60 mg statin group completed this study. In all the 3 groups, hs-CRP level significantly increased at 12 and 24 h after PCI compared with the preoperative levels (P<0.05). The patients in 60 mg statin group showed significantly lower levels of CKMB, cTNI, and hs-CRP at 24 h after PCI than those in 20 mg statin group (P<0.05), and had also a significantly lower incidence of total MACE within 30 days after PCI (2.6% vs 26.5%, P=0.003) resulting primarily from significantly reduced myocardial infarction associated with PCI (2.6% vs 20.6%, P=0.016). The adverse drug reactions were comparable among the 3 groups (P>0.05). CONCLUSIONS: Intensive pretreatment with 60 mg/day atorvastatin calcium can significantly reduce myocardial infarction related to PCI with good safety in elderly patients with CHD.

[Rapid simultaneous determination of ten major flavonoids in Tetrastigma hemsleyanum by UPLC-MS/MS].

In this study, a rapid and sensitive analytical method was developed for the determination of 10 major compounds (procyanidin B1, catechin, procyanidin B2, rutin, isoquercitrin, kaempferol-3-O-rutinoside, astragalin, quercitrin, quercetin, and kaempferol) in Tetrastigma hemsleyanum by using ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-MS/MS) in multiple-reaction monitoring (MRM) mode. UPLC-MS/MS assay with negative ion mode was performed on a Waters CORTECS C18 (2.1 mm x 100 mm, 1.6 µm) with the mobile phase consisting of acetonitrile (A) and 0.1% aqueous formic acid (B) in gradient elution at a flow rate of 0.25 mL · min(-1) and the column temperature was set at 45 °C. Under the optimized chromatographic conditions, good separation for 10 target compounds were obtained including chiral isomer procyanidins B1 and B2 were completely separated within 8.5 min. Satisfactory linearity was achieved with wide linear range and fine determination coefficient (r > 0.996 6), the overall recoveries were ranged from 95.44%-110.40% with the RSD ranging from 2.37%-8.69%. It is the first report about simultaneous analysis of 10 major flavonoids components in Tetrastigma hemsleyanum by using UPLC-MS/MS method, which affords highly sensitive, specific, speedy and efficient method for quality control of Tetrastigma hemsleyanum

[Qualitative and quantitative analysis of major constituents in Tetrastigma hemsleyanum by HPLC-Q-TOF-MS and UPLC-QqQ-MS].

A qualitative analytical method of liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS) was developed for identification of multi-constituents and an analytical method was developed for simultaneously determining 4 major compounds (rutin, isoquercitrin, kaempferol-3-0-rutinoside, and astragalin) in Tetrastigma hemsleyanum Diels et Gilg. The HPLC-Q-TOF-MS assay was performed on a Welch Ultimate XB-C18 column (4.6 mm x 150 mm, 5 microm) with the mobile phase consisting of acetonitrile (A) and water containing 0.1% Formic acid (B) in gradient mode at a flow rate of 0.8 mL x min(-1). The column temperature was at 30 degrees C, and negative ion mode was used for TOF-MS. The UPLC-QqQ-MS assay was performed on a Waters CORTECS C18 (2.1 mm x 100 mm, 1.6 microm) with the mobile phase consisting of acetonitrile (A) and water containing 0.1% formic acid (B) in gradient mode at a flow rate of 0.25 mL x min(-1). The column temperature was at 45 degrees C, and MRM mode was used for QqQ-MS. Based on the retention time and MS spectra, 24 compounds were identified or tentatively characterized by comparing with reference substances or literatures. For quantitative the linear range of 4 detected compounds were good (r > 0.9966), and the overall recoveries ranged from 98.27% to 101.58%, with the RSD ranging from 3.15% to 5.88%. The results indicated that new approach conbined HPLC-Q-TOF-MS and UPLC-QqQ-MS was applicable in qualitative and quantitative quality control of Tetrastigma hemsleyanum.