Characteristics of Oil-in-Oil Emulsions under AC Electric Fields.

Emulsions have been applied in a number of industries such as pharmaceutics, cosmetics, and food, which are also of great scientific interest. Although aqueous emulsions are commonly used in our daily life, oil-in-oil (o/o) emulsions also play an irreplaceable role in view of their unique physics and complementary applications. In this paper, we investigate typical behaviors of organic droplets surrounded by organic medium (o/o emulsions) with different functional groups controlled by the AC electric field. Droplet behaviors can be catalogued into five types: namely, "no effect", "movement", "deformation", "interface rupture", and "disorder". We identify the key dimensionless number Wee·Ca, combined with the channel geometry, for characterizing the typical behaviors in silicon oil/1,6-hexanediol diacrylate and mineral oil/1,6-hexanediol diacrylate emulsions. Unlike aqueous emulsion, the Maxwell-Wagner relaxation inhibits the electric effect and leads to an effective frequency, ranging from 0.5 to 3 kHz. The increasing viscosity of the droplet facilitates the escalation by promoting the shearing effect under the same flow conditions. Ethylene glycol droplets primarily show the efficient coalescence even at a low Wee·Ca, which is attributed to the attraction of free charges induced by the increasing conductivity. In 1,6-hexanediol diacrylate/silicon oil emulsion, the droplet tends to form a liquid film that expands into the entire channel due to the affinity of the droplet to the channel wall. A variety of elongated columns are observed to oscillate between the electrodes at high voltages. These findings can contribute to understanding the electrohydrodynamic physics in o/o emulsion and controlling droplet behaviors in a fast response, programmable, and high-throughput way. We expect that this droplet manipulation technology can be widely adopted in a broad range of chemical synthesis and biological and material science.

Effect of C7-T1 Extensional Posterior Transpedicle Osteotomy on Mobility and Quality of Life in Patients with Ankylosing Spondylitis Complicated with Lumbar Kyphosis and Related Factors.

Objective: To analyze the effect of C7-T1 extensional posterior transpedicular vertebral osteotomy (PSO) on mobility and quality of life in patients with ankylosing spondylitis (AS) and lumbar kyphosis. Methods: This study was conducted from February 2019 to February 2021 and a total of 38 patients with AS combined with kyphosis from Tianjin Union Medical Center, Tianjin, China, were selected for the study. After performing all preoperative examinations, all patients were treated with C7-T1 extensional posterior PSO osteotomy. The patients' operation and follow-up, pain degree as a Visual analogue scale (VAS) score and sagittal balance index changes before and after surgery, spinal function measured as; Bath Ankylosing Spondylitis Functional Index (BASFI) score and quality of life by Scoliosis Research Society-22 (SRS-22) score, were observed before and after surgery. Pearson correlation coefficient was used to analyze the correlation between patients' quality of life and BASFI score. Results: After surgery, the pain of the patients' back was significantly relieved, the patients' appearance and trunk balance function were significantly improved, and the symptoms related to nerve function were not significantly aggravated. No complications such as infection, internal fixation failure or spinal decompensation occurred in all patients. VAS score, kyphosis Cobb Angle and Sagittal Vertical Axis (SVA) of all patients showed P < .05 before and 1 year after surgery. BASFI score 1 year after surgery decreased significantly than that before surgery (P < .05). 1 year after surgery, body function, pain symptoms, self-image and psychological state of the patients were significantly improved, and the SRS-22 total score of the patients 1 year after surgery increased significantly than before surgery (P < 0.05). BASFI score was negatively correlated with SRS-22 score by Pearson correlation coefficient analysis (P < .05). Conclusion: C7-T1 extensional posterior PSO osteotomy has a good effect in the treatment of AS patients with lumbar kyphosis. The sagittal balance was well-restored with improvement in patients' quality of life after surgery, which makes C7-T1 osteotomy worthy of clinical application to treat patients suffering from AS combined with lumbar kyphosis.

Foraminoplasty affects the clinical outcomes of discectomy during percutaneous transforaminal endoscopy: a two-year follow-up retrospective study on 64 patients.

Objective: The aim of this study was to assess the significance of how the degree of injury of the facet joint affects clinical outcomes in foraminoplasty.Methods: We retrospectively enrolled 64 patients treated with percutaneous endoscopic transforaminal discectomy with foraminoplasty (PETDF) from January of 2015 to December of 2016. The patients were divided into two groups depending on whether the articular surface of the facet joint was damaged. Preoperative, perioperative, demographic data, and radiographic parameters for these two groups were extracted and compared.Results: There were no significant differences between the two groups in terms of the duration of operation (p = 0.331), intraoperative blood loss volume (p = 0.631), the weight of disc (p = 0.274) or cut bone (p = 0.526). There were no significant differences between the two groups for VAS or ODI at the same time point (p > 0.05). There were significant differences in the VAS scores of low-back pain at 24 h and 24 months after surgery in the injured group. There were significant differences in ISH, ISA, rate of lumbar instability, recurrent herniation, and Macnab scores between the two groups at 24 months after surgery (p < 0.05). The regression equation between ISA and ISH was Y = 4.237 + 0.565x (where Y denotes an increase of ISA; X, reduction of ISH; F = 6.219, p = 0.015). The Poisson ratio was 0.363 (p = 0.003).Conclusions: PETDF is effective and safe for the treatment of lumbar disc herniation. However, when foraminoplasty destroys the articular surface of the facet joint, there may be increases in lumbar instability and recurrence rate post-operation.

Clinical Outcomes of Atlantoaxial Dislocation Combined with Osteoporosis Using Posterior Atlantoaxial Rod, Screw Fixation, and Posterior Interfacet Fusion: A Retrospective Study of 21 Cases.

BACKGROUND Surgical procedures on atlantoaxial dislocation combined with osteoporosis remain controversial. This study was established to assess the mid-term clinical outcomes of atlantoaxial dislocation combined with osteoporosis using posterior atlantoaxial rod, screw fixation and posterior interfacet fusion. MATERIAL AND METHODS From January 2017 to January 2020, 21 patients (4 males and 17 females) with coexisting atlantoaxial dislocation and osteoporosis who underwent posterior atlantoaxial rod and screw fixation were included in our study with an average age of 64±8.1 years (range, 57-74 years). The subjective and objective symptoms, together with the neurological function of the patients were measured. Radiography and magnetic resonance imaging (MRI) were performed, Japanese Orthopaedic Association (JOA) score for spinal cord function and VAS score for pain recovery was assessed. RESULTS JOA and visual analog scale (VAS) score were significantly improved at 14±5.9 month follow-up compared with pretreatment values. Complete or almost complete anatomical reduction was observed in all 21 patients. All patients had good bony fusion at the final follow-up. No screw-loosening or atlantoaxial redislocation occurred in 21 cases. The only complication was mild numbness in the C2 innervation area of the posterior occipital region in 6 cases, which had no effect on life. CONCLUSIONS The results suggested that posterior atlantoaxial rod, screw fixation system, and posterior interfacet fusion could achieve satisfactory initial results for the treatment of atlantoaxial dislocation combined with osteoporosis.

Treatment of cerebrospinal fluid leak after spine surgery.

Owing to the complexity of spinal surgery, there is a great prevalence of dural tear causing cerebrospinal fluid (CSF) leakage. Many studies focused on suture repair for dural tear to stop CSF leak. Now some new treatment strategies have shown a promising effect that is listed as follows: 1) creating watertight dural closure to stop CSF leak with the help of dural substitute material; and 2) retarding CSF leak by changing pressure difference, including reducing the subarachnoid fluid pressure, increasing the epidural space pressure and both. In fact several methods mentioned above are usually combined to treat CSF leak. However, no update review summarized the relevant studies implemented in recent years. In this review, the authors would compare the effects of different dural closure techniques, and introduce the latest treatment methods and mechanisms.

[White matter injury of spinal cord in rats with chronic fluorosis and recovery after defluoridation].

OBJECTIVE: To explore the injury mechanism for white matter of spinal cord and the improvement of function after defluoridation. METHODS: A total of 120 Wistar rats were separated randomly into 4 groups (n = 30 each). High flouriod group received high concentration NaF water (200 mg/L) to establish fluorosis model; control group distilled water; defluoridation group high concentration NaF water (200 mg/L) for 12 weeks and then distilled water for 12 weeks; defluoridation control group. The urinary contents of fluoride were detected at Weeks 4, 8 and 12. The first two groups were sacrificed at Week 12 while the other two groups at Week 24. The spinal cord functions were detected by BBB scale and incline plate test. Their cervical spinal cord tissues were collected and observed under electron microscope. The expression of myelin basic protein (MBP) in thoracic cord was detected by immunohistochemistry and Western blot. The comparison of measurement data was performed with F test and correlation analysis. Cytological changes of white matter in spinal cord were detected after chronic fluorosis. RESULTS: The spinal functions of high flouriod and defluoridation groups were inferior to those of the control groups. But no difference existed among the groups. Pathological manifestations of chronic white matter injury of spinal cord could be found in high flouriod and defluoridation groups. The MBP expression in spinal cord of fluorosis and defluoridation groups decreased in comparison with those in control groups. But no difference existed among them. CONCLUSION: White matter injury of spinal cord is present in chronic fluorosis rats. Defluoridation for a short time offers no recovery.

Identification of a potential signature to predict the risk of postmenopausal osteoporosis.

BACKGROUND: Postmenopausal osteoporosis (PMOP) is related to the elevated risk of fracture in postmenopausal women. Thus, to effectively predict the occurrence of PMOP, we explored a novel gene signature for the prediction of PMOP risk. METHODS: The WGCNA analysis was conducted to identify the PMOP-related gene modules based on the data from GEO database (GSE56116 and GSE100609). The "limma" R package was applied for screening differentially expressed genes (DEGs) based on the data from GSE100609 dataset. Next, LASSO Cox algorithm were applied to identify valuable PMOP-related risk genes and construct a risk score model. GSEA was then conducted to analyze potential signaling pathways between high-risk (HR) score and low-risk (LR) score groups. RESULTS: A novel risk model with five PMOP-related risk genes (SCUBE3, TNNC1, SPON1, SEPT12 and ULBP1) was developed for predicting PMOP risk status. RT-qPCR and western blot assays validated that compared to postmenopausal non-osteoporosis (non-PMOP) patients, SCUBE3, ULBP1, SEPT12 levels were obviously elevated, and TNNC1 and SPON1 levels were reduced in blood samples from PMOP patients. Additionally, PMOP-related pathways such as MAPK signaling pathway, PI3K-Akt signaling pathway and HIF-1 signaling pathway were significantly activated in the HR-score group compared to the LR-score group. The circRNA-gene-miRNA and gene-transcription factor networks showed that 533 miRNAs, 13 circRNAs and 40 TFs might be involved in regulating the expression level of these five PMOP-related genes. CONCLUSION: Collectively, we developed a PMOP-related gene signature based on SCUBE3, TNNC1, SPON1, SEPT12 and ULBP1 genes, and higher risk score indicated higher risk suffering from PMOP.

[Etiology and treatment of postoperative spinal cord injury for patients undergoing laminectomy for fluorosis thoracic canal stenosis].

OBJECTIVE: To elucidate the etiology of postoperative spinal cord injury (PSCI) for patients undergoing laminectomy for fluorosis thoracic canal stenosis (FTCS) and summarize the methods of diagnosis and treatment. METHODS: From 2006 to 2009, a total of 192 FTCS cases underwent laminectomy. Among them, 16 cases with gradual postoperative neural deterioration were finally diagnosed as PSCI on MRI.One case of intraoperative spinal cord injury was excluded so that only 15 cases were included. RESULTS: All cases were treated immediately with incision cite puncture and dehydration.Neural function recovered after secondary operation as JOA score improved from 3.00 ± 1.14 to 7.72 ± 1.41 at 12 months follow-up.Statistical analysis demonstrated a linear correlation between the diagnosis time and the improvement of JOA score. CONCLUSION: Hematoma and fluid leakage are the common reasons of PSCI for FTCS patients. Meticulous hemostasis, usage of artificial dura matter and partial negative pressure drainage are valuable preventive measures.

Optimal strategy of in-game items with conspicuous consumption: whether to provide the grinding version?

In the virtual world, whether or not to spend money on in-game items distinguishes paying players from non-paying players. Due to the existence of conspicuous psychology, paying players will greatly increase their conspicuous utility after purchasing an item in addition to the utility of the item itself. In this case, whether providing different versions of items can bring greater revenue to the game company is a question worth investigating. In this study, two analytical models considering conspicuous intensity are developed to compare the optimal pricing strategy of the game company providing the single-version item or dual-version items. The single-version item can only be purchased, while a relatively low-quality version that can be obtained by grinding is provided in the dual-version strategy. Grinding means using time in games to get items instead of spending in games. The results suggest that it is more profitable for companies to offer dual-version items when conspicuous intensity is strong. Game companies can also adjust the time needed to acquire the grinding version item and the quality gap between the two versions to achieve greater revenue. The research contributes to providing a theoretical basis and decision support for game companies to decide whether to provide different versions of in-game items.

AC-electric-field-controlled multi-component droplet coalescence at microscale.

Droplet coalescence with fast response, high controllability and monodispersity has been widely investigated in industrial production and bioengineering. Especially for droplets with multiple components, programmable manipulation of such droplets is crucial for practical applications. However, precise control of the dynamics can be challenging, owing to the complex boundaries and the interfacial and fluidic properties. AC electric fields, with their fast response and high flexibility, have attracted our interest. We design and fabricate an improved flow-focusing microchannel configuration together with a non-contact type of electrode featuring asymmetric geometries, based on which we conduct systematic investigations of the AC-electric-field-controlled coalescence of multi-component droplets at the microscale. Parameters such as flow rates, component ratio, surface tension, electric permittivity and conductivity were given our attention. The results show that droplet coalescence in different flow parameters can be achieved in milliseconds by adjusting the electrical conditions, which shows high controllability. Specifically, both the coalescence region and reaction time can be adjusted by a combination of applied voltage and frequency, and unique merging phenomena have appeared. One is contact coalescence with the approach of paired droplets, while the other is squeezing coalescence, which occurs in the start position and promotes the merging process. The fluid properties, such as the electric permittivity, conductivity and surface tension, present a significant influence on merging behavior. The increasing relative dielectric constant leads to a dramatic reduction of the start merging voltage from the original 250 V to 30 V. The range of effective voltage for coalescence decreases with the addition of surfactant, offering a stricter and yet higher selectivity on electrical conditions, about 1500 V. The conductivity presents a negative correlation with the start merging voltage due to the reduction of the dielectric stress, from 400 V to 1500 V. Finally, we achieve the precise fabrication process of the Janus droplet via implementation of the proposed method, where the components of the droplets and the coalescence conditions are well controlled. Our results can serve as a potent methodology to decipher the physics of multi-component droplet electro-coalescence and contribute to applications in chemical synthesis, bioassay and material synthesis.

Evaluation of enlarged laminectomy with lateral mass screw fixation in relieving nerve root symptoms and correcting kyphosis for cervical myelopathy and radiculopathy.

Purpose: This study aimed to compare the surgical efficacy of enlarged laminectomy with lateral mass screw fixation (EL-LMSF) and anterior cervical decompression and fusion (ACDF) for multilevel cervical myelopathy and radiculopathy (CMR) related to kyphosis. Methods: 75 patients were retrospectively reviewed and divided into ACDF and EL-LMSF group. Clinical results including operative time, blood loss, and postoperative complications were compared. The JOA scoring system was used to evaluate spinal cord function and the VAS score evaluate nerve root pain severity. Cervical alignment a C2-C7 was measured with Cobb method and compared to confirm the reconstruction effect. Results: Data on 75 patients (M/F: 41:34; EL-LMSF/ACDF:42/33) with the mean age of 57.5 years (range 43-72 year old) were reviewed retrospectively. Discectomy and/or sub-toal corpectomy in ACDF group was performed with a mean of 3.24 levels (range, 3-4). Enlarged laminectomy in EL-LMSF group was performed with a mean of 3.89 enlarged levels (range, 3-5). The procedure of ACDF group showed a shorter operation time (103 ± 22 min vs. 125 ± 37 min, P = 0.000) and less blood loss (78 ± 15 ml vs. 226 ± 31 ml, P = 0.000) compared than that of the EL-LMSF group. Patients treated with EL-LMSF indicated lower VAS for upper extremity (1.3 ± 1.7 vs. 3.3 ± 1.3, P = 0.003) and better curvature corrected (10.7 ± 4.2° vs. 8.5 ± 3.5°, P = 0.013). The difference were of statistical significance. No statistical difference was found after surgery in the JOA score (14.1 ± 1.7 vs. 13.5 ± 2.1, P = 0.222). During the follow-up period, 15.2% of patients in the ACDF group had complications including 2 cases with transient dysphagia, 1 case with C5 palsy, 1 case with axial pain, and 1 case with screw pullout 3 month after surgery. However, only 9.5% of cases in the EL-LMSF group experienced complications, including 3 cases of axial pain and 1 case of epidural hematoma. Conclusion: The EL-LMSF procedure requires a longer operation time and more blood loss because of the incision of the stenosed foramen. However, the procedure has obvious advantages in relieving nerve root symptoms and correcting cervical curvature with fewer postoperative complications.

[Damage of blood brain barrier of spinal cord in rats with chronic fluorosis].

OBJECTIVE: To explore the impairment mechanisms of blood brain barrier in spinal cord and observe the changes of matrix metalloproteinase-9 (MMP-9) and functional improvement in rats with chronic fluorosis. METHODS: A total of 120 Wistar rats were divided randomly into 4 groups, high fluoride (fed by water with a high concentration of sodium fluoride at 200 mg/L), high fluoride control (fed by distilled water), defluorination (fed by water with a high concentration of sodium fluoride at 200 mg/L for 12 weeks and then distilled water for 12 weeks) and defluorination control (n = 30 each). The urinary contents of fluoride were detect for 4 groups at Weeks 4, 8 and 12. The high fluoride and control groups were sacrificed at Week 12 while the defluorination and defluorination control groups at Week 24. Their cervical spinal cords were collected for electron microscope examinations. The expression of MMP-9 protein in thoracic cord was detected by immunohistochemistry and Western blot. Quantitative analysis of function of blood brain cord barrier was performed by the technique of Evans blue. The comparison of measurement data was performed with F test and correlation analysis. The cytological changes of neurons in thoracic spinal cord were detected after chronic fluorosis. RESULTS: Under electron microscope, the pathological manifestations of chronic damage in blood brain barrier could be found. As compared with the high fluoride control group, the content of Evans blue increased markedly in spinal cord of the high fluoride group (29.2 ± 0.1 vs 0.7 ± 0.1 mg/L, P < 0.01). It was higher in the defluorination group than that in the defluorination control group. But there was no significant difference with the high fluoride group (29.2 ± 0.1 vs 28.9 ± 0.2 mg/L, P > 0.01). And the expression of MMP-9 increased in spinal cord of the fluorosis and defluorination groups in comparison with those in the control group. But no difference existed among them. CONCLUSION: The damage of blood brain barrier of spinal cord occurs probably as a result of a higher expression of MMP-9 in rats with chronic fluorosis. Defluorination for a short time may not recover.

Study on complex dynamics for the waste electrical and electronic equipment recycling activities oligarchs closed-loop supply chain.

Nowadays, with more and more WEEE (waste electrical and electronic equipment) being abandoned, WEEE recycling activities are increasingly popular. In this paper, we build a closed-loop supply chain model and focus on the recycling behaviors of the members in this supply chain, which contains two manufacturers, the retailer, and the consumer. In the reverse chain, we set up dual channels and design two recycling methods: sell-back method and trade-in method. We use classical backward induction to run the model. And then we analyze the stability of the system and the impacts of some essential parameters by numerical simulation. The speed of the manufacture's decision adjustment has a significant effect on the stability of the model. Manufacturers should adopt a stable rather than radical price adjustment strategy in order to achieve stable profit growth in the whole supply chain and avoid a chaotic price war. Manufacturers should increase innovation investment in recycling technology to reduce the cost of remanufacturing products and improve the initiative in market competition. In the end, we adopt the parameter control method and the decision-making method to control chaos, and they both have a good control effect.

Research on equilibrium strategy and emergency management of three oligarch battery manufacturers under cooperative promotion and low-carbon policy.

People are increasingly paying much attention to battery technology, especially the zinc-nickel battery and the lithium battery, for solving energy shortages and environmental contamination. Meanwhile, the drastic change in the external outside environment has brought a huge challenge to manage the battery industry chain. Therefore, in the uncertain external environment, the study of supply chain competition between lithium battery and new nickel battery manufacturers is the focus of this paper. We build a cooperative game model under the demand disturbance and a non-cooperative game under the background of product promotion. The results show that (i) the price set by the manufacturer increases with technical improvement when consumers are more sensitive to the technical level. (ii) The optimal price of all manufacturers will drop as the CETRC (carbon emission technology renewal coefficient) increases. (iii) The price of zinc-nickel batteries will be higher than that of lithium battery as the market promotion rate is in the middle range. In the model, the supply chain determines different optimal prices according to the different ranges of the demand disturbance.

Design and Manufacture of Millimeter-Scale 3D Transformers for RF-IC.

The development of radio-frequency integrated circuits (RF-IC) necessitates higher requirements for the size of microtransformers. This paper describes millimeter-scale 3D transformers in millimeter-scale, solenoidal, and toroidal transformers manufactured using Micro-electromechanical Systems (MEMS). Two through-silicon via (TSV) copper coils with a high aspect ratio are precisely interleaved on a reserved air core (magnet core cavity) with a vertical height of over 1 mm because of the thickness of the substrate, which increases the performance while reducing the footprint. The effects of the wire width, coil turns, magnetic core, and substrate on the performance of the two transformers are discussed through numerical simulations. When an air core is present, solenoidal transformers are better than toroidal transformers in terms of performance and footprint; however, the gap decreases when the size is reduced. Additionally, the magnetic core significantly improves the performance of the toroidal transformer compared to that of the solenoid. Thus, the toroidal transformer has a higher potential for further size reduction. The two types of transformers were then manufactured completely using MEMS and electroplating. This paper discusses the influence of various parameters on millimeter-scale 3D transformers and realizes processing in silicon, which provides the foundation for integrating transformers in a chip.

Visualization and Analysis of Air Pollution and Human Health Based on Cluster Analysis: A Bibliometric Review from 2001 to 2021.

Bibliometric techniques and social network analysis are employed in this study to evaluate 14,955 papers on air pollution and health that were published from 2001 to 2021. To track the research hotspots, the principle of machine learning is applied in this study to divide 10,212 records of keywords into 96 clusters through OmniViz software. Our findings highlight strong research interests and the practical need to control air pollution to improve human health, as evidenced by an annual growth rate of over 15.8% in the related publications. The cluster analysis showed that clusters C22 (exposure, model, mortality) and C8 (health, environment, risk) are the most popular topics in this field of research. Furthermore, we develop co-occurrence networks based on the cluster analysis results in which a more specific keyword classification was obtained. These key areas include: "Air pollutant source", "Exposure-Response relationship", "Public & Occupational Health", and so on. Future research hotspots are analyzed through characteristics of the cluster groups, including the advancement of health risk assessment techniques, an interdisciplinary approach to quantifying human exposure to air pollution, and strategies in health risk assessment.

Influence of hinge position on the effectiveness of expansive open-door laminoplasty for cervical spondylotic myelopathy.

STUDY DESIGN: A prospective study. OBJECTIVE: To assess the influence of different hinge positions on the clinical results of expansive open-door laminoplasty (EOLP) for cervical spondylotic myelopathy (CSM). SUMMARY OF BACKGROUND DATA: EOLP is currently the most widely adopted surgical treatment for CSM, although many long-term clinical follow-up studies have reported that most patients recover satisfactorily after EOLP, there have been numerous reports regarding postoperative complications, such as stubborn axial symptoms and segmental motor paralysis. The hinge position in EOLP plays a decisive role in determining the openness of the door so that affect clinical outcomes, whereas no thorough studies on the hinge positions have been published. METHODS: A total of 102 consecutive CSM patients who underwent EOLP from February 2006 to February 2007 were enrolled in this randomized controlled trial and assigned alternatively to 1 of 2 treatment groups. Using a random digits table, 57 patients with the hinge located at the inner margin of the lateral mass were classified as wide-open group, whereas 45 patients with the hinge positioned at the lamina margin served as narrow-open group. All patients were followed up over 24 months, clinical results including operation duration, intraoperative bleeding volume, Japanese Orthopaedic Association scores, axial symptoms assessment, and C5 palsy, and radiologic examinations like C2-C7 angle, cervical curvature index, and range of motion were analyzed statistically. RESULTS: In this study, there were no significant differences in terms of operation duration, intraoperative bleeding volume, neural function recovery rate, curvature index, and range of motion. The neural functions were satisfactorily improved after EOLP in both groups (Japanese Orthopaedic Association score developed from 7.2 ± 1.1 to 14.3 ± 1.2 and 8.1 ± 0.9 to 15.1 ± 1.6 with P = 0.01 and 0.02, respectively), whereas the severity of axial symptoms was significantly lower in narrow-open group than in wide-open group (P<0.01). The incidence of C5 palsy in wide-open group was higher than that in narrow-open group (5.3% vs. 0%), even though the difference did not reach statistical significance (1-tailed Fisher exact test, P = 0.17). CONCLUSIONS: Our results indicate that proper inward shift of the hinge can ensure effectiveness of surgical decompression, avoid an excessive backward shift of the spinal cord, reduce the incidence of C5 palsy, and alleviate the severity of axial symptoms. In addition, an inward shift should be cautious and contraindicated in patients with fluorosis cervical stenosis, ossification of posterior longitudinal ligament, and ossification of ligament flavum.

Influence of hinge position on the effectiveness of open-door expansive laminoplasty for cervical spondylotic myelopathy.

OBJECTIVE: To assess the influence of different hinge positions on clinical results of expansive open-door laminoplasty (EOLP) for cervical spondylotic myelopathy (CSM). METHODS: A total of 102 CSM patients who underwent EOLP from February 2006 to February 2007 were enrolled in this randomized controlled trial. Using a random digits table, 57 patients with the hinge located at the inner margin of the lateral mass were classified as wide-open group, while 45 patients with the hinge positioned at the lamina margin served as narrow-open group. All patients were observed over 24 months, and the clinical and radiological results were analyzed statistically. RESULTS: There were no significant differences in operation duration, intraoperative bleeding volume, Japanese Orthopaedic Association (JOA) scores, cervical curvature index, range of motion and neural function recovery rate. The neural functions were satisfactorily improved after surgery in both groups, while the severity of axial symptoms was significantly lower in the narrow-open group than in the wide-open group (P equal to 0.003). The incidence of C(5) palsy in the wide-open group was higher than that in the narrow-open group (5.3% vs 0), even though the difference did not reach statistical significance (one tailed Fisher's exact test, P equal to 0.17). CONCLUSIONS: Proper inward shift of the hinge can ensure effectiveness of surgical decompression, avoid an excessive backward shift of the spinal cord, decrease the incidence of C(5) palsy and alleviate the severity of axial symptoms.

DNA methyltransferase 3 beta mediates the methylation of the microRNA-34a promoter and enhances chondrocyte viability in osteoarthritis.

Osteoarthritis (OA) is characterized by destruction of articular cartilage with an imbalance between synthesis and degradation of extracellular matrix (ECM). In the current study, we explored the role of microRNA-34a (miR-34a) and the behind epigenetic mechanism in the degradation of ECM in OA. Using miRNA-based microarray analysis, we found that miR-34a was overexpressed in cartilage tissues of OA patients relative to patients with acute traumatic amputations. Moreover, its expression was positively correlated with the ECM degradation and inflammation. Mechanistically, miR-34a targeted MCL1, and possible target genes of miR-34a were enriched in the PI3K/AKT pathway. Furthermore, DNMT3B inhibited miR-34a by promoting miR-34a methylation. Functional experiments using CCK-8, flow cytometry, Safranin O staining, RT-qPCR, ELISA, Western blot, and HE staining revealed that miR-34a inhibitor suppressed ECM degradation and inflammatory response of chondrocytes and cartilage tissues. By contrast, downregulation of DNMT3B and MCL1 reversed the repressive effects of miR-34a inhibitor in vitro and in vivo. Altogether, our findings establish that silencing of miR-34a by DNMT3B could effectively reduce chondrocyte ECM degradation and inflammatory response in mice by targeting MCL1 and mediating the downstream PI3K/AKT pathway. This present study revealed that miR-34a knockdown might develop a novel intervention for OA treatment.

[Relationship between expression of MMP-9 and presyrinx state of experimental syringomyelia of rabbits].

OBJECTIVE: To investigate the relationship between the expression of MMP-9 and the formation of spinal cord edema in presyrinx state of experimental syringomyelia in rabbits and evaluate the inhibitory function of doxycycline in the formation of spinal cord edema in presyrinx state. METHODS: A total of 96 Chinese white rabbits were divided randomly into four groups:kaolin group (n = 24), doxycycline treatment group (n = 24), physiological saline group (n = 24) and control group (n = 24). Under ketamine anesthesia, 0.6 ml of 25% kaolin solution was injected into the cisterna magna in all rabbits of kaolin and doxycycline groups while 0.6 ml of 37°C physiological saline into the cistern in those of saline group; doxycycline (25 mg × kg(-1) × d(-1)) was applied post-operatively for doxycycline group. At Days 1, 3, 7 and 14 after kaolin injection, 6 rabbits of all four groups were selected randomly for sacrificing. Water content of spinal cord could be obtained. The expression of MMP-9 activity was measured by Western blot and immunohistochemistry. RESULTS: At any time point, the water content of spinal cord and the expression of MMP-9 in kaolin group improved obviously more than those of saline and control groups (P < 0.01). At Day 1, there was no marked difference in the water content of spinal cord and the expression of MMP-9 between doxycycline and kaolin groups (P > 0.05). At other time points, the water content of spinal cord and the expression of MMP-9 in doxycycline group markedly decreased than those of kaolin group (P < 0.01). CONCLUSION: In the model of experimental syringomyelia, MMP-9 plays an important role in causing edema in presyrinx state. Thus doxycycline may be used to prevent and treat syringomyelia.