Serum and cerebrospinal fluid tau protein level as biomarkers for evaluating acute spinal cord injury severity and motor function outcome

Tau protein, a microtubule-associated protein, has a high specific expression in neurons and axons. Because traumatic spinal cord injury mainly affects neurons and axons, we speculated that tau protein may be a promising biomarker to reflect the degree of spinal cord injury and prognosis of motor function. In this study, 160 female Sprague-Dawley rats were randomly divided into a sham group, and mild, moderate, and severe spinal cord injury groups. A laminectomy was performed at the T8 level to expose the spinal cord in all groups. A contusion lesion was made with the NYU-MASCIS impactor by dropping a 10 g rod from heights of 12.5 mm(mild), 25 mm(moderate) and 50 mm(severe) upon the exposed dorsal surface of the spinal cord. Tau protein levels were measured in serum and cerebrospinal fluid samples at 1, 6, 12, 24 hours, 3, 7, 14 and 28 days after operation. Locomotor function of all rats was assessed using the Basso, Beattie and Bresnahan locomotor rating scale. Tau protein concentration in the three spinal cord injury groups(both in serum and cerebrospinal fluid) rapidly increased and peaked at 12 hours after spinal cord injury. Statistically significant positive linear correlations were found between tau protein level and spinal cord injury severity in the three spinal cord injury groups, and between the tau protein level and Basso, Beattie, and Bresnahan locomotor rating scale scores. The tau protein level at 12 hours in the three spinal cord injury groups was negatively correlated with Basso, Beattie, and Bresnahan locomotor rating scale scores at 28 days(serum: r =-0.94; cerebrospinal fluid: r =-0.95). Our data suggest that tau protein levels in serum and cerebrospinal fluid might be a promising biomarker for predicting the severity and functional outcome of traumatic spinal cord injury.

An expert consensus on the evaluation and treatment of acute thoracolumbar spine and spinal cord injury in China

This is an expert consensus on the evaluation and treatment of thoracolumbar spinal injury, estab- lished from February 2009 to July 2010. The expert consensus consists mainly of six parts with a total of 54 recommendations including the overview （one item）; pre-hospital care （one item）; evaluation and diagnosis （13 items）; treatment （23 items）; prevention and treatment of major com- plications （12 items）; and rehabilitation （four items）. This is the first time that Chinese experts have published a consensus on spine and spinal cord injury. The expert consensus was established based on Delphi methods, literature analysis, and clinical experiences. Each recommendation is supported by and was interpreted using multi-level evidences. The level of agreement with the rec- ommendation among the panel members was assessed as either low, moderate, or strong. Each panel member was asked to indicate his or her level of agreement on a 5-point scale, with ＂1＂ cor- respondJng to neutrality and ＂5＂ representJng maxJmum agreement. Scores were aggregated across the panel members and an arithmetic mean was calculated. This mean score was then translated into low, moderate, or strong. After all of the votes were collected and calculated, the results showed no low-level recommendations, 10 moderate-level recommendations, and 44 strong-level recom- mendations. An expert consensus was reached and was recognized by Chinese spine surgeons. Wide-scale adoption of these recommendations is urgent in the management of acute thora- columbar spine and spinal cord injury in a broader attempt to create a standard evaluation and treatment strategy for acute thoracolumbar spine and spinal cord injury in China.

Treadmill step training promotes spinal cord neural plasticity after incomplete spinal cord injury

A large body of evidence shows that spinal circuits are significantly affected by training, and that intrinsic circuits that drive locomotor tasks are located in lumbosacral spinal segments in rats with complete spinal cord transection. However, after incomplete lesions, the effect of treadmil training has been debated, which is likely because of the difficulty of separating spontaneous stepping from specific training-induced effects. In this study, rats with moderate spinal cord contusion were sub-jected to either step training on a treadmil or used in the model （control） group. The treadmil training began at day 7 post-injury and lasted 20 ± 10 minutes per day, 5 days per week for 10 weeks. The speed of the treadmil was set to 3 m/min and was increased on a daily basis according to the tolerance of each rat. After 3 weeks of step training, the step training group exhibited a sig-nificantly greater improvement in the Basso, Beattie and Bresnahan score than the model group. The expression of growth-associated protein-43 in the spinal cord lesion site and the number of tyrosine hydroxylase-positive ventral neurons in the second lumbar spinal segment were greater in the step training group than in the model group at 11 weeks post-injury, while the levels of brain-derived neurotrophic factor protein in the spinal cord lesion site showed no difference between the two groups. These results suggest that treadmil training significantly improves functional re-covery and neural plasticity after incomplete spinal cord injury.

Dynamic changes and surveillance function of prion protein expression in gastric cancer drug resistance

AIM:To explore the dynamic changes of prion protein (PrPc) in the process of gastric cancer drug resistance and the role of PrPc expression in the prognosis of gastric cancer patients receiving chemotherapy.METHODS:A series of gastric cancer cell lines resistant to different concentrations of adriamycin was established,and the expression of PrPc,Bcl-2 and Bax was detected in these cells.Apoptosis was determined using Annexin V staining.Western blotting and immunohisto-chemistry were performed to detect the expression of PrPc in patients receiving chemotherapy and to explore the role of PrPc expression in predicting the chemosensitivity and the outcome of gastric cancer patients receiving chemotherapy.Follow-up was performed for 2 years.RESULTS:PrPc expression was increased with the increase in drug resistance.Bcl-2,together with PrPc,increased the level of anti-apoptosis of cancer cells.Increased PrPc expression predicted the enhanced level of anti-apoptosis and resistance to anticancer drugs.PrPc expression could be used as a marker for predicting the efficacy of chemotherapy and the prognosis of gastric cancer.Increased PrPc expression predicted both poor chemosensitivity and a low 2-year survival rate.Contrarily,low PrPc expression predicted favorable chemosensitivity and a relatively high 2-year survival rate.CONCLUSION:PrPc expression is associated with histological types and differentiation of gastric cancer cells;The PrPc expression level might be a valuable marker in predicting the efficacy of chemotherapy and the prognosis of gastric cancer patients receiving chemotherapy.

Mesenchymal Stem Cells Attenuate Vascular Remodeling in Monocrotaline-induced Pulmonary Hypertension Rats

Intravenous and intratracheal implantation of mesenchymal stem cells (MSCs) may offer ameliorating effects on pulmonary hypertension (PH) induced by monocrotaline (MCT) in rats. The aim of this study was to examine the anti-remodeling effect of intravenous MSCs (VMSCs) and intratracheal MSCs (TMSCs) in rats with PH, and the underlying mechanisms. MSCs were isolated from rat bone marrow and cultured. PH was induced in rats by intraperitoneal injection of MCT. One week after MCT administration, the rats were divided into 3 groups in terms of different treatments: VMSCs group (intravenous injection of MSCs), TMSCs group (intratracheal injection of MSCs), PH group (no treatment given). Those receiving saline instead of MCT served as negative control (control group). Pulmonary arterial structure was pathologically observed, pulmonary arterial dynamics measured, and remodeling-associated cytokines Smad2 and Smad3 detected in the lungs, three weeks after MCT injection. The results showed that PH group versus control group had higher pulmonary arterial pressure (PAP) and wall thickness index (WTI) 21 days after MCT treatment. The expression of phosphorylated (p)-Smad2 and the ratio of p-Smad2/Smad2 were much higher in PH group than in control group. Fluorescence-labeled MSCs were extensively distributed in rats’ lungs in VMSCs and TMSCs groups 3 and 14 days after transplantation, but not found in the media of the pulmonary artery. WTI and PAP were significantly lower in both VMSCs and TMSCs groups than in PH group three weeks after MCT injection. The p-Smad2 expression and the ratio of p-Smad2/Smad2 were obviously reduced in VMSCs and TMSCs groups as compared with those in PH group. In conclusion, both intravenous and intratracheal transplantation of MSCs can attenuate PAP and pulmonary artery remodeling in MCT-induced PH rats, which may be associated with the early suppression of Smad2 phosphorylation via paracrine pathways.

An anthropomorphic phantom study of effect of lung tumor size and location on dosimetric parameters

Objective： The aim of the study was to study the effect of the size and location of tumors on the normal lung dose-volume parameters for lung cancer. Methods： Three spheres with diameters of 2, 3 and 4 cm made of tissue-equivalent materials used for simulating tumors were inserted into the upper lobe, middle lobe, lower lobe of the right lung, upper lobe, lower lobe of the left lung of the Rando phantom, respectively. Five-field simplified IMRT （slMRT） planning were designed. The prescribed dose was 60 Gy/2 Gy/30 f, 99% of the planning target volume received this dose. Dose-volume parameters of normal lung tissues including relative volume of lung receiving 〉 5, 10, 20, 30 and 50 Gy （V5, Vl0, V2o, V30, V50）, and mean lung dose （MLD） were analyzed and compared. Results： For the dose-volume parameters, the diameter and the position of the tumor had a significant effect （P 〈 0.05）. With the diameter expanding from 2 to 3 cm, the parameters associated with tumor lying in various lobes increased by a range between 3.83%-125.38%, while the parameters linked with tumors on different lobes increased by a range between 10.46%-51.46% with the diameter expanding from 3 to 4 cm. Conclusion： Location and size of sphere-like tumor have an obvious effect on dose-volume parameters. Knowing about the degree of influence will help oncologists and physicists better evaluate treatment planning, then the probability of radiation pneumonitis can be reduced.

Does repair of spinal cord injury follow the evolutionary theory?

Lower vertebrates, such as fish and amphibians, and higher vertebrates in embryonic development can acquire complete regeneration of complex body structures, including the spinal cord, an important part of the central nervous system. However, with species evolution and development, this regenerative capacity gradually weakens and even disappears, but the cellular and molecular mechanisms remain poorly understood. We explored the differences in mechanisms of spinal cord regeneration capability between lower and higher vertebrates, investigated differences in their cellular and molecular mechanisms and between the spinal cord structures of lower vertebrates and mammals, such as rat and monkey, to search for theoretical evidence and therapeutic targets for nerve regeneration in human spinal cord.

A preliminary report on adjuvant analgesic efficacy of HANS in opioid tolerant patients with cancer pain

Objective： To observe the adjuvant analgesic efficacy of Han＇s Acupoint Nerve Stimulator （HANS） in opioid tolerant patients with cancer pain. Methods： A prospective non-controlled study was conducted. Opioid tolerant patients with cancer pain were enrolled and treated with both routinely analgesics and adjuvant HANS （2/100 Hz for 30 min/d, 5 d on and 2 d off for two weeks）. Cancer pain, quality of life （QOL）, anxiety and depression were assessed before enrollment and on d 8 and d 15 with the BPI-C, EORTC QLQ-C30, and self-rating anxiety scale （SAS）/ self-rating depression scale （SDS）, respectively; the therapeutic frequency of breakthrough pain （BP） and daily opioid dose were also recorded. Results： Totally 47 patients meeting the inclusion criteria participated in this study; 43 patients completed the two-week treatment and assessment. The mean scores of patient＇s ＂worst＂ and ＂least＂ pain intensity assessed with BPI-C decreased significantly on d 8 and d 15; the therapeutic frequency of BP also significantly decreased; but the average daily dose of opioids did not change significantly. For the nine symptoms in EORTC QLQ-C30 assessment, the mean scores of pain, fatigue, constipation and insomnia were significantly lower on d 8 and d 15 compared with baseline; the mean scores of the overall health status, nausea/vomiting and the incidence rates of both anxiety and depression also decreased significantly on d 15. Conclusions： To opioid tolerant patients with cancer pain, adjuvant treatment with HANS could improve pain release and patients＇ QOL by decreasing the severity of pain, fatigue, constipation, insomnia and other concomitant symptoms; it could also decrease the incidence rates of anxiety and depression.

Variation of Protein's Expression Correlated to the Drug Resistance after Sequential Anti-cancer Treatment in Human Lung Cancer Cell Line

Multi-drug resistance is one of the leading causes for failure to treat patients with cancer. This study is to explore the expression of the proteins correlated with chemoresistance in a human lung cancer cell line （LPET-a-1） repeatedly treated by anti-cancer drugs.

Dosimetric evaluation of CR, 3DCRT and two types of IMRT for breast cancer after conservative surgery

Objective: The purpose of this study was to compare the dose distribution and dose volume histogram (DVH) of the planning target volume (PTV) and organs at risk (OARs) among conventional radiation therapy (CR), three-dimensional conformal radiation therapy (3DCRT), two-step intensity-modulated radiation therapy (TS-IMRT) and direct machine parameter optimization intensity-modulated radiation therapy (DMPO-IMRT) after breast-conserving surgery. Methods: For each of 20 randomly chosen patients, 4 plans were designed using 4 irradiation techniques. The prescribed dose was 50 Gy/2 Gy/25 f, 95% of the planning target volume received this dose. The cumulated DVHs and 3D dose distributions of CR, 3DCRT, TS-IMRT and DMPO-IMRT plans were compared. Results: For the homogeneity indices, no statistically significant difference was observed among CR, 3DCRT, TS-IMRT and DMPO-IMRT while the difference of the conformality indices were statistically significant. With regard to the organs at risk, IMRT and 3DCRT showed a significantly fewer exposure dose to the ipsilateral lung than CR in the high-dose area while in the low-dose area, IMRT demonstrated a significant increase of exposure dose to ipsilateral lung, heart and contralateral breast compared with 3DCRT and CR. In addition, the monitor units (MUs) for DMPO-IMRT were approximately 26% more than those of TS-IMRT and the segments of the former were approximately 24% less than those of the latter. Conclusion: Compared with CR, 3DCRT and IMRT improved the homogeneity and conformity of PTV, reduced the irradiated volume of OARs in high dose area but IMRT increased the irradiated volume of OARs in low dose area. DMPO-IMRT plan has fewer delivery time but more MUs than TS-IMRT.

Introduction of Linac quality management experience

The Elekta Precise medical Linac is a typical modern high energy accelerator which uses advanced digital technology and gets acknowledged around the world. It provides both X rays and electrons at various megavoltage energies including two photon energies （6 and 15 MV） and several electron energies （e.g. 6, 9, 12, 15, 18 and 22 MeV）. The commonly used dose rate for X rays is 500 MU/min, while that for electors is 400 MU/min. The accelerator is equipped with beam intensity modulation cm2. The width of MLC at 40 pairs of MLC for photon covering fields up to 40 × 40 the isocenter is 10 mm. The maximum leakage is less than 0.3%

Clinical Application of Photodynamic Therapy

Photodynamic therapy（PDT） is a new medical technology, the study on photodynamic therapy was in full swing in the past two decade. Scientists have made great progress in it. Photosensitizer,oxygen and light source play important role in photodynamic therapy. PDT is a light activated chemotherapy. A photon is adsorbed by a photosensitizer which moves the drug into an excited state. The excited drug can then pass its energy to oxygen to create a chemical radical called “singlet oxygen”. Singlet oxygen attacks cellular structures by oxidation. Such oxidative damage might be oxidation of cell membranes or proteins. When the accumulation of oxidative damage exceeds a threshold level,the cell begins to die. Photodynamic therapy allows selective treatment of localized cancer. PDT involves administration of a photosensitizer to the patients, followed by delivery of light to the cancerous region. The light activates the agent which kills the cancer cells. Without light,the agent is harmless. As a new therapy,photodynamic Therapy has great Advantage in treating cancers. 1. PDT avoids systemic treatment. The treatment occurs only where light is delivered, hence the patient does not undergo go needless systemic treatment when treating localized disease. Side-effects are avoided, from losing hair or suffering nausea to more serious complications. 2. PDT is selective. The photosensitizing agent will selectively accumulate in cancer cells and not in surrounding normal tissues. Hence ,there is selective targeting of the cancer and sparing of surrounding tissues. 3. when surgery is not possible. PDT kills cancer cells but does not damage collagenous tissue structures,and normal cells will repopulate these structures. Hence,if a patient has cancer in a structure that cannot be removed surgicaily（eg. ,the upper bronchi of the lung） ,PDT can still treat the site. 4. PDT is repeatable. Uniike radiation therapy,PDT can be used again and again. Hence,it offers a means of longterm management of cancer even if complete cure is not attainable.

Factors influencing postoperative mortality one year after surgery for hip fracture in Chinese elderly population

Background Disability and death following hip fracture is becoming more common as the population ages. Previous reports have focused on the selection of internal fixation methods and the analysis of the perioperative therapeutic results in the Chinese population. Few studies have focused on factors influencing medium and long term survival after surgery for hip fracture. We conducted a retrospective study on the factors influencing survival one year after hip fracture surgery in our elderly Chinese population to provide a reference for improved treatment and to enhance efficacy. Methods Records from patients undergoing treatment for hip fracture at our hospital from October 2009 through June 2011 were retrospectively reviewed. Through telephone follow-up, the health condition of each patient was surveyed, and the 1-year postoperative mortality was analyzed. The patients＇ age, gender, fracture type, pre-injury health condition, mobility, complications, surgical timing, surgical types, methods of anesthesia, and postoperative complications were analyzed. Univariate and multivariate regression analysis was performed on relevant influencing factors. Results A total of 184 patients had complete data and were followed-up for 12-23 months （average, 16.5 months）. There were 30 deaths （16.3%） at one-year. Univariate analysis revealed that factors such as age, gender, fracture-type, number of co-existing diseases, complications such as chronic obstructive pulmonary disease or sequelae of stroke, American society of Anesthesiology （ASA） scores, anesthesia methods, pre-injury activity, and post-operative complications were significantly different between survival versus mortality groups （P 〈0.05）. Multivariate regression analysis revealed that age, ASA score, pre-injury mobility and combined chronic obstructive pulmonary disease were independent risk factors for death. Conclusion Full consideration of medium-/long-term risk factors in the treatment of hip fracture in the elderly, selection of appropriate anesthesia and treatment methods, and improved pre-surgical health conditions would reduce postoperative mortality and enhance surgical efficacy.

Dynesys dynamic stabilization system for the lumbar degenerative disease： a preliminary report from China

Background Dynesys dynamic stabilization system in 2007. Therefore, it was a new technique for Ch about Dynesys in China. The objective of this study degenerative disease in China. was first implanted in patients in 1994, and introduced to China nese orthopedics and hence necessary to collect clinical data was to report the preliminary results of Dynesys for the lumbar Methods Twenty-seven patients were treated with the Dynesys between July 2007 and January 2009. The diagnosis included degenerative spondylolisthesis （12 cases）, degenerative spinal stenosis （nine cases）, and lumbar intervertebral disc herniation （six cases）. Back pain and leg pain were evaluated using 100-mm visual analog scales （VAS）. The Oswestry Disability Index （ODI） was used to evaluate the patients＇ function. The intervertebral disc height and range of motion at the operative level were taken on radiographs. Results All the patients were followed-up, with an average of （22.40±4.23） months （range 15±32 months）. VAS of back pain and leg pain were improved significantly （P 〈0.05） at foUow-up. The ODI scores were reduced from （62.58±12.01）% preoperatively to （15.01±5.71）% at follow-up （P 〈0.05）. The preoperative mean height of the intervertebral disc was （11.21±1.58） mm （range 8.5±13.8 mm） and mean was （10.10±1.78） mm （range 7.0±13.4 mm） at follow-up （P 〈0.05）. The mean range of motion of the implanted segment was （6.00±1.79）° （range 2.5-9.3°） preoperatively and （5.47±1.27）° （range 2.9±7.8°） at follow-up （P=0.11）. Conclusions The preliminary results of Dynesys for the lumbar degenerative disease in China are similar to the published results of other countries. It can significantly improve the clinic symptoms and preserved motion at the level of implantation. However, the long-term follow-up data need to be collected.

Differentiation of adipose-derived stem cells toward nucleus pulposuslike cells induced by hypoxia and a three-dimensional chitosan-alginate gel scaffold in vitro

Background Injectable three-dimensional （3D） scaffolds have the advantages of fluidity and moldability to fill irregularshaped defects,simple incorporation of bioactive factors,and limited surgical invasiveness.Adipose-derived stem cells （ADSCs） are multipotent and can be differentiated toward nucleus pulposus （NP）-Iike cells.A hypoxic environment may be important for differentiation to NP-like cells because the intervertebral disc is an avascular tissue.Hence,we investigated the induction effects of hypoxia and an injectable 3D chitosan-alginate （C/A） gel scaffold on ADSCs.Methods The C/A gel scaffold consisted of medical-grade chitosan and alginate.Gel porosity was calculated by liquid displacement method.Pore microstructure was analyzed by light and scanning electron microscopy.ADSCs were isolated and cultured by conventional methods.Passage 2 BrdU-labeled ADSCs were co-cultured with the C/A gel.ADSCs were divided into three groups （control,normoxia-induced,and hypoxia-induced groups）.In the control group,cells were cultured in 10％ FBS/DMEM.Hypoxia-induced and normoxia-induced groups were induced by adding transforming growth factor-β1,dexamethasone,vitamin C,sodium pyruvate,proline,bone morphogenetic protein-7,and 1％ ITS-plus to the culture medium and maintaining in 2％ and 20％ O2,respectively.Histological and morphological changes were observed by light and electron microscopy.ADSCs were characterized by flow cytometry.Cell viability was investigated by BrdU incorporation.Proteoglycan and type Ⅱ collagen were measured by safranin O staining and the Sicool method,respectively.mRNA expression of hypoxia-inducing factor-1α （HIF-1α）,aggrecan,and Type Ⅱ collagen was determined by reverse transcription-polymerase chain reaction.Results C/A gels had porous exterior surfaces with 80.57％ porosity and 50-200 μm pore size.Flow cytometric analysis of passage 2 rabbit ADSCs showed high CD90 expression,while CD45 expression was very low.The morphology of induced ADSCs resembled that of NP cells.BrdU immunofluorescence showed that most ADSCs survived and proliferated in the C/A gel scaffold.Scanning electron microscopy showed that ADSCs grew well in the C/A gel scaffold.ADSCs in the C/A gel scaffold were positive for safranin O staining.Hypoxia-induced and normoxia-induced groups produced more proteoglycan and Type Ⅱ collagen than the control group （P ＜0.05）.Proteoglycan and Type Ⅱ collagen levels in the hypoxia-induced group were higher than those in the normoxia-induced group （P ＜0.05）.Compared with the control group,higher mRNA expression of HIF-1α,aggrecan,and Type Ⅱ collagen was detected in hypoxia-induced and normoxiainduced groups （P ＜0.05）.Expression of these genes in the hypoxia-induced group was significantly higher than that in the normoxia-induced group （P ＜0.05）.Conclusion ADSCs grow well in C/A gel scaffolds and differentiate toward NP-like cells that produce the same extracellular matrix as that of NP cells under certain induction conditions,which is promoted in a hypoxic state.

Percutaneous Nucleoplasty Using Coblation Technique for the Treatment of Chronic Nonspecific Low Back Pain： 5-year Follow-up Results

Background： This study evaluated the efficacy of percutaneous nucleoplasty using coblation technique for the treatment of chronic nonspecific low back pain （LBP）, after 5 years of follow-up. Methods： From September 2004 to November 2006, 172 patients underwent percutaneous nucleoplasty for chronic LBP in our department. Forty-one of these patients were followed up for a mean period of 67 months. Nucleoplasty was performed at L3/4 in 1 patient; L4/5 in 25 patients; L5/$1 in 2 patients; L3/4 and L4/5 in 2 patients; L4/5 and L5/$1 in 7 patients; and L3/4, L4/5, and L5/$1 in 4 patients. Patients were assessed preoperatively and at 1 week, 1 year, 3 years, and 5 years postoperatively. Pain was graded using a 10-cm Visual Analogue Scale （VAS） and the percentage reduction in pain score was calculated at each postoperative time point. The Oswestry Disability Index （ODI） was used to assess disability-related to lumbar spine degeneration, and patient satisfaction was assessed using the modified MacNab criteria. Results： There were significant differences among the preoperative, 1-week postoperative, and 3-year postoperative VAS and ODI scores, but not between the 3- and 5-year postoperative scores. There were no significant differences in age, sex, or preoperative symptoms between patients with effective and ineffective treatment, but there were significant differences in the number of levels treated, Pfirrmann grade of intervertebral disc degeneration, and provocative discography findings between these two groups. Excellent or good patient satisfaction was achieved in 87.9% of patients after 1 week, 72.4% after 1 year, 67.7% after 3 years, and 63.4% at the last follow-up. Conclusions： Although previously published short- and medium-term outcomes after percutaneous nucleoplasty appeared to be satisfactory, our long-term follow-up results show a significant decline in patient satisfaction over time. Percutaneous nucleoplasty is a safe and simple technique, with therapeutic effectiveness for the treatment of chronic LBP in selected patients. The technique is minimally invasive and can be used as part of a stepwise treatment plan for chronic LBP.

Comparison of Functional and Radiological Outcomes Between Two Posterior Approaches in the Treatment of Multilevel Cervical Spondylotic Myelopathy

Background：Posterior cervical decompression is an accepted treatment for multilevel cervical spondylotic myelopathy （CSM）.Each posterior technique has its own advantages and disadvantages.In the present study,we compared the functional and radiological outcomes of expansive hemilaminectomy and laminoplasty with mini titanium plate in the treatment of multilevel CSM.Methods：Forty-four patients with multilevel CSM treated with posterior cervical surgery in Department of Orthopedic Surgery,Beijing Army General Hospital from March 2011 to June 2012 were enrolled in this retrospective study.Patients were divided into two groups by surgical procedure：Laminoplasty （Group L） and hemilaminectomy （Group H）.Perioperative parameters including age,sex,duration of symptoms,opcrative duration,and intraoperative blood loss were recorded and compared.Spinal canal area,calculated using AutoCAD software（Autodesk Inc.,San Rafael,CA,USA）,and neurological improvement,evaluated with Japanese Orthopedic Association score,were also compared.Results：Neurological improvement did not differ significantly between groups.Group H had a significantly shorter operative duration and significantly less blood loss.Mean expansion ratio was significantly greater in Group L （77.83 ± 6.41%） than in Group H （62.72 ± 3.86%） （P 〈 0.01）.Conclusions：Both surgical approaches are safe and effective in treating multilevel CSM.Laminoplasty provides a greater degree of enlargement of the spinal canal,whereas expansive hemilaminectomy has the advantages of shorter operative duration and less intraoperative blood loss.

Reference values of brachial-ankle pulse wave velocity for Northern Chinese

Background Brachial-ankle pulse wave velocity （baPWV） is a reliable method for measuring arterial elasticity, but the absence of reference value for baPWV has limited its wide use. We conducted an epidemical study in north China to investigate the reference value of baPWV for Chinese people and its influential factors. Methods A total of 974 identified healthy subjects were recruited in this study. The values of baPWV were evaluated noninvasively with an automatic device. Results For healthy population, the mean value of baPWV was higher for male （P 〈0.001）. Multiple regression analysis demonstrated that both age and systolic blood pressure were positively associated with baPWV for male and female （P 〈0.001）. BaPWV value was higher in male than in female in younger group （〈50 years） but not in older group （P〈-0.001）. The upper limits of baPWV were 1394/1264 cm/s, 1435/1361 cm/s, 1552/1433 cm/s, 1597/1609 cm/s and 1798/1915 cm/s for healthy male/female at 10 years interval （age range 20-70 years）. Conclusions Aging is the most important reason of arterial stiffness, but the effect of age on baPWV augmentation is greater for healthy female than their male counterpart. The reference values of baPWV by sex and age are very useful for clinical and preventive medicine.

Depression, anxiety and influencing factors in patients with acute pulmonary embolism

Background Psychological distress has been widely studied in many cardiovascular and pulmonary diseases, but the condition in acute pulmonary embolism （APE） is unknown. The purpose of this study was to investigate levels of depression and anxiety and their influencing factors in APE patients. Methods Sixty consecutive patients with APE were subjected to investigation of depression and anxiety by the Beck Depression Inventory and State-Trait Anxiety Inventory, and 60 community-based subjects were enrolled as controls. APE patients were stratified as high-risk, intermediate-risk and low-risk according to the disease severity. Scores of depression and anxiety were compared by statistical analysis using paired t tests between APE patients and controls, and by analysis of variance within the APE patients with the three risk stratification. Factors influencing depression and anxiety were evaluated. Results The mean age of the patients （38 males and 22 females） was （52＋12） years. APE patients displayed higher scores of depression （P=0.04） and anxiety （P=0.001） compared with controls. Patients in the high-risk group displayed higher scores of depression （P=0.004） and anxiety （P=0.001） compared with those in the intermediate- and low-risk groups. Depression scores were highly correlated with anxiety scores （r=0.60, P 〈0.001）. Both depression and anxiety inversely related to risk stratification （P 〈0.01）, age （P 〈0.05）, and arterial blood oxygen pressure （PaO2） （P 〈0.05）. Linear regression analysis showed that PaO2 was independently inversely related to both depression （P 〈0.01） and anxiety （P 〈0.05）; risk stratification and age were independently inversely related to anxiety （P 〈0.05）. Conclusions Patients of APE suffered high levels of depression and anxiety, which were negatively influenced by PaO2 risk stratification and age.