Myasthenia gravis is an autoimmune disease resulting from the production of antibodies against acetylcholine receptors of the endplate. These antibodies impair postjunctional membrane and reduce the number of functional acetylcholine receptors of endplate. Thymectomy is an effective therapeutic method for adult myasthenic patients. In this paper, the author reviewed the pathophysiological characteristics and problems related to anesthesia, such as preoperative evaluation, the effect of preoperative medical treatment on the anesthesia, patients'response to muscle relaxants and postoperative management.

Objective To study the paracrine effect of hypoxic preconditioned umbilical cord mesenchymal stem cells (UCMSCs) on the proliferation,migration and osteogenic differentiation of osteoblasts.Methods UCMSCs were cultured under hypoxia and normal oxygen condition before two UCMSCs conditioned media were obtained.After that,MG-63 cells were cultured in three groups:hypoxia conditioned medium group,normoxia conditioned medium group and DMEM control group.The proliferation of MG-63 cells was detected by mosmann tetrazoline colorimetry( MTT) method after 1,3 and 5 days.The migratory ability of MG-63 cells was detected by scratch assay .After 21 days′culture , the formation of osteogenic calcium nodules was detected by Alizarin red staining.ELISA method was used to detect the content of vascular endothelial growth factor ( VEGF) in hypoxia and normoxia conditioned medium.Results The MTT test showed that the proliferation ability of MG-63 cells in hypoxia conditioned medium group and normoxia conditioned medium group was greater than in the DMEM control group.The difference was statistically significant ( P <0.05).Furthermore, the proliferation ability of cells in hypoxia conditioned medium group were much greater than cells in normoxia culture medium group.The difference was statistically significant (P<0.05).Scrath assay showed that the migratory ability of MG-63 cells in hypoxia conditioned medium group and normoxia conditioned medium group was greater than cells in DMEM control group,and cells in hypoxia conditioned medium group was much greater than cells in normoxia conditioned medium group. After 21 days′culture,we found that the number of calcium nodules was the largest in hypoxia conditioned medium group, followed by normoxia conditioned medium group and DMEM control group.ELISA showed that the content of VEGF in hypoxia conditioned medium was higher than that in normoxia conditioned medium and the difference was statistically significant (P<0.01).Conclusion The paracrine function of UCMSCs can be enhanced by hypoxia,thus improving the proliferation,migration and osteogenic differentiation of osteoblasts.

Objective To observe the morphologic protection effect of intra-articular injection of osteoprotegerin (OPG)on articular cartilage in a rabbit model of osteoarthritis (OA).Methods Sixty male New Zealand rabbits were randomly divided into 3 groups:OPG group (n=20),sham-operated group (n=20) and PBS group (n=20).In OPG group and PBS group,each rabbit underwent anterior cruciate ligament transection (ACLT) in left knee joint,then 0.1 ml OPG solution or PBS were injected into the left knee for 8 weeks (5 times a week) in OPG group and PBS group,respectively.In sham-operated group,the anterior cruciate ligament was just exposed without transection,and then the incision was closed.All rabbits were sacrificed 12 weeks after operation,and the left knee joints were obtained.The Pelletier score and Mankin score were used to evaluate the macroscopic and microscopic cartilage morphology.Results The score of femoral condyle cartilage and tibial plateau cartilage was 1.80±0.89 and 1.80±0.77 in OPG group,respectively,and 3.10±0.97 and 3.20±0.77 in PBS group.However,there was no statistical difference in Pelletier score between the sham-operated group and the OPG group.Consistent with the macroscopic data,the OPG group has a significantly lower Mankin score involving cartilage structure (2.65±0.88),chondrocyte (1.35±0.71),Safranin O staining (1.83±0.83),tidemark integrity (0.30±0.47) and total score (6.13±1.97) compared with the PBS group (4.52±1.09,1.85±0.63,2.80±0.75,0.65±0.49,and 9.83±1.98,respectively).The OPG group has a significantly higher total Mankin score compared with the sham-operated group (4.80±1.25),however,there were no statistical differences in four subitem scores between the two groups.Moreover,the cartilage thickness in OPG group was 371.84±38.94 μm,255.09±74.82 μm in PBS group,and 404.68±15.97 μm in the sham-operated group,and the differences were statistically significant between three groups.Conclusion OPG has a protective effect on articular cartilage and can slow the progression of OA by reducing the grade of synovitis,decreasing the volume of osteophytes,and suppressing the loss of cartilage thickness.

Objective To study the effect of intra-articular injection of dehydroepiandrosterone (DHEA) on the balance of ADAMTS/TIMP-3 system in a rabbit osteoarthritis models.Methods Sixty rabbits were underwent bilateral anterior cruciate ligament transection (ACLT).Rabbits were randomizedn to the following treatment:one knee of each rabbit was treated with 100 μmol/L DHEA dissolved in dimethylsulphoxide (the experimental group) and the other knee was treated under the same schedule using dimethylsulphoxide (the control group) 4 weeks after transection,once a week for eight weeks.Twelve weeks after ACLT,all rabbits were killed after X-ray assessment and the knee joints were evaluated by gross morphology and histology.The concentration of hydroxyproline and glycosaminoglycan in the cartilage were analyzed.The mRNA expression of ADAMTS-4,ADAMTS-5,tissue inhibitor of metalloproteinases-3 (TIMP-3),transforming growth factor (TGF)-β1.Aggrecan and Collagen Ⅱ in the cartilage were analyzed using reverse transcription polymerase chain reaction (RT-PCR).The protein expression of aggrecan ARGxx and Collagen Ⅱ in the cartilage were analyzed by Western blot.Results By Mann-Whitney test,Gross morphologic scores on femoral condyle and tibial plateau in the control group were significantly higher than the experi-mental group (Z=-3.517,P＜0.01 ; Z=-2.518,P＜0.05).By unpaired Student's t test,histological evaluation showed that the grade of cartilage damage in the experimental group [(5.3±1.2) μg/ml] were less severe than that in the control group (10.1 ± 1.3,P＜0.01).The concentration of hydroxyproline [(5.7±0.3,23.6± 1.7) μg/ml] and glycosaminoglycan (30±4) in the experimental group increased significantly when compared with the control group [(4.6±0.5),(18.5±1.4),(24±4) μg/ml,P＜0.01].The mRNA expression of ADAMTS-4 (0.15±0.03)and ADAMTS-5 (0.10±0.04) in the experimental group decreased significantly compared with the control group (0.29±0.08,0.15±0.05; all P＜0.05).The mRNA expression of TIMP-3 (0.85±0.10),TGF-β1(1.2±0.4),Aggrecan (0.87±0.31) and Collagen Ⅱ (2.74±0.59) in the experimental group increased significantly when compared with the control group (0.70±0.13,0.8±0.4,0.49±0.16,2.2±0.5; all P＜0.05).The protein expression of Aggrecan ARGxx (0.53±0.10) in the experimental group decreased significantly when compared with the control group (0.81±0.12,P＜0.01).The protein expression of Collagen Ⅱ (2.3±0.7) in the experimental group increased significantly when compared with the control group (1.7±0.5,P＜0.05).Conclusion DHEA protects against cartilage degradation and inhibits the progression of OA,TGF-β1,Aggrecan and Collagen Ⅱ in cartilage may be the mechanism of the protective effect of DHEA on OA.

Objective To explore the safety and outcomes of thoracoscopic esophagectomy for esophageal cancer.Methods The clinical data of 22 patients with esophageal cancer received thoracoscopic minimally invasive esophagectomy ( study group ) were retrospectively analyzed and compared with 46 patients underwent conventional open thoracic esophagectomy( control group) .The medium-term clinic outcomes of the two groups were compared. Results Compared to the control group,the study group showed significantly longer operation time[(183 ±37)mins vs (239 ±41)mins,t=6.19,P=0.002],less intraoperative blood loss[(95 ±33)mL vs (115 ±27)mL,t=5.04, P=0.004],shorter postoperative hospital stay[(15.8 ±6.2)d vs (17.5 ±7.1)d,t=5.62,P=0.003],and more removed lymph nodes[(11.6 ±4.2) vs (10.3 ±5.8),t=-3.19,P=0.018)].No significant difference was observed in the survival rate between the two groups (χ2 =0.358,P=0.449) .Conclusion There is no difference in medium-term clinic outcomes between the two kinds of esophagectomy.The patients with esophageal cancer received thoracoscopic minimally invasive esophagectomy has less complication and quick recovery.And the technology should be widely applied.

Objective:To investigate the effects of propofol on cerebrospinal fluid pressure(CSFP),mean arterial pressure(MAP),cerebral perfusion pressure(CPP) and heart rate(HR)during induction of anesthesia in patients underwent intracranial operation. Methods: In 20 patients scheduled for elective craniotomy, an epidural catheter was placed into subarachanoid. Fentanyl(2 ?g/kg), intravenousl Midazolam (0.04~0.05mg/kg) and propofol (2mg/kg) were administered respectively prior to induction of anesthesia. CSFP,MAP,CPP and HR were monitored at 2min,5min after propofol administration and 2,5,10min after another supplementary dose of propofol 1mg/kg addendum during endotracheal intubation. Results: Compared with the preanesthetic baseline values, CSFP, CPP, and MAP all decreased significantly during induction(P

Objective To evaluate the association of magnetic resonance angiography (MRA),diffusion-weighted imaging (DWI) and the ABCD2 score assessments with secondary cerebral infarction after transient ischemic attack (TIA).Methods Intracranial vascular MRA,cranial DWI and ABCD2 score were retrospectively analyzed in 162 cases with TIA.The impact of TIA on survival time was assessed using the univariate Kaplan-Meier curve by Log-rank test.Hazard ratio (HR) and 95 ％ confidence interval (CI) of secondary cerebral infarction after TIA predicted by MRA,DWI and ABCD2 score were analyzed by Cox multivariable regression.Results Among the 162 patients with first attack of TIA,86 cases (53.1 ％) developed cerebral infarction within 90 d,of which 22 cases (13.6％) developed secondary cerebral infarction within 0 7 d,27 cases (16.7％) within 8～30d and 37 cases (22.8％) within 31-90 d.Single factor analysis by Kaplan-Meier curve showed that moderate to severe intracranial vascular stenosis diagnosed by MRA,positive DWI and moderate to high ABCD2 score were obviously related to cerebral infarction after first attack of TIA (all P＜0.001 or 0.01).Cox multifactor risk model indicated that age ≥70 y,moderate to severe intracranial vascular stenosis,positive DWI,moderate to high ABCD2 score were the risk factors for secondary cerebral infarction within 90 d after TIA (HR=1.782,2.245,1.964,1.204,95％CI:1.171-2.256,1.627 3.097,1.273-3.031,1.050-1.381,respectively,P＜0.05,0.01 or 0.001).Conclusions Intracranial artery stenosis examination may be more valuable than DWI and ABCD2 score in evaluating the outcome of TIA.

Objective To determine the content of ferulic acid, water and extract of Angelica formula particles, provide a reliable method for evaluation and quality control, and compare the quality of Angelica formula particles and Angelica pieces. Methods HPLC method was used with Kromasil C18 column (4.6 mm×250 mm, 5μm), flow rate of 1.0 mL/min, detection wavelength of 316 nm, column temperature at 28 ℃. The mobile phase was acetonitrile-0.05%phosphoric acid in water gradient elution system. Results Ferulic acid showed good linear relationship in the range of 0.033-0.165 μg (r=0.999 8). The average recovery was 98.78% and RSD=0.99%. Angelica formula particles met the quality requirement in the content indicators, the content of ferulic acid was higher than Angelica pieces. Conclusion The HPLC method for determination of ferulic acid in Angelica formula particles is simple and reliable, with good reproducibility, and can be used as the quality control method of Angelica formula particles.

Objective To predict a value of ischemia modified albumin (IMA) levels for assessing secondary cerebral infarction in patients with transient ischemic attack (TIA) in anterior circulation.Methods 105 patients with TIA in anterior circulation admitted to the hospital within 3 hours were retrospectively studied.Combined with ABCD2 score,the correlations of IMA levels at 3 h,6 h and 12 h with secondary cerebral infarction after anterior circulation TIA were analyzed.Results IMA level was 75.28 u/L within 3h after TIA,and the sensitivity and specificity of TIA in anterior circulation were 66.7％ and 76.2％ respectively.In the total of 105 patients,16 cases (15.2％) suffered from secondary cerebral infarction within 7d,and 21 cases (20.0％) within 8～30d.The serum IMA levels were (87.43±19.89)U/L,(63.88±12.51)U/L and (61.21±12.28)U/L at 3h,6h and 12h after TIA,respectively.A simple analysis showed that there was a linear correlation between the IMA level and ABCD2 scores (P=0.000,r=0.666).Kaplan-Meier survival curve analysis showed that the increased IMA level within 3h,and moderate to high ABCD2 score were the risk factors for secondary cerebral infarction after TIA in anterior circulation (P=0.012,0.041).Conclusions Early detection of IMA has a clinical value similar to ABCD2 score to predict secondary cerebral infarction in patients with TIA in anterior circulation.

Cone beam CT(CBCT)data of 4 550 impacted mandibular third molars were divided into 6 groups by the direction of teeth im-paction.Analyzed by SPSS 19.0 statistical package and Pearson Chi-square Test,the incidence of disto-lingual roots was 5.38% and was various with different impation direction.