Objective To identify the model parameters of surface Electromyography (sEMG) by comparison between simulated and recorded signals. Methods A physiological model of sEMG signal was established basing on several logical hypothetical conditions, such as motor unit action potentials (MUAP), motor unit recruitment and firing behavior caused by excitation, architecture of volume conductor and other simulated factors. According to the matched shapes between the simulated and recorded sEMG signals, a group of model parameters was obtained; according to the similar power spectrum variations of real sEMG signals, decreased muscle fiber conduction velocity (MFCV) was applied to simulate the sEMG signals of the fatigued muscle. Results The experimental results showed that the simulated superimposed MUAP shapes could be matched with the recorded MUAPs satisfactorily by adjusting some proper physiological parameters of the model. When the MFCV of each fiber was assumed to decrease, the mean and median frequency (MNF, MDF) of the simulated sEMG signals declined, and this phenomenon was very similar to that of the recorded sEMG signals and could be used to interpret the muscle fatigue process. Conclusion This model provides an effective approach to simulate real sEMG signals, and the simulated signals can also be used to help the analysis of recorded sEMG signals.

Hepatitis, Autoimmune ; Humans ; Immune Tolerance ; Liver Transplantation

Objective To discuss how to protect the intracranial vertebral artery and posterior inferior cerebellar artery by observing and measuring the intracranial vertebral artery in the surgery adopt far lateral approach. Methods Mimicking far lateral approach, 20 adult cadaveric heads connected to neck fixed with 10% formalin were dissected. Intracranial segment of the vertebral arteries and their main branches were exposed and measured under operating microscope. Results The intracranial vertebral artery joined with the contralateral one into the basilar artery after traveling through the atlanto-occipital sulcus. The relationship between the vertebral artery and the hypoglossal nerve is close. Thirty sides (75%) of the vertebral arteries traveled to pons medulla sulcus in front of the hypoglossal nerve roots and 2 sides (5%) behind the hypoglossal nerve roots, while 8 sides (20%) traveled among the hypoglossal nerve roots; 70% of the vertebral arteries were contacted to the hypoglossal nerve roots, 30% of which compressed the hypoglossal nerve. The main branches of intracranial segment of the vertebral arteries were the posterior inferior cerebellar arteries, the anterior spinal arteries, the posterior meningeal arteries,and some perforating arteries. Posterior inferior cerebellar arteries all originated from the intracranial vertebral artery were the largest vertebral artery's branches; their trip was mostly loop-shaped and they had close relationship with Ⅸ, Ⅹ, Ⅺ cranial nerves. The starting points of the posterior inferior cerebellar arteries were different, even in the same specimen, but most of them originated from the upper 1/3intracranial vertebral artery. No anterior inferior cerebellar artery was noted originated from the vertebral artery in our specimen. Anterior spinal arteries originated from the vertebral arteries joined with the branches of the bilateral vertebral arteries and traveled down through the tortuous anterior median fissure to supply the spinal cord. Conclusion Being familiar with the characteristics and anatomic vertebral arteries variations of the intracranial vertebral artery and its branches can contribute to identify and protect the intracranial segment of the vertebral artery and its main branches in the surgery adopt far-lateral approach.

BACKGROUNDThymectomy is considered the most effective treatment in patients with myasthenia gravis. This study aimed to explore the predictors of postoperative myasthenic crisis in patients with myasthenia gravis after thymectomy.

METHODSClinical records of 243 patients with myasthenia gravis who underwent thymectomy were reviewed retrospectively. The following factors were analyzed in relation to the occurrence of myasthenic crisis after thymectomy: gender, age, duration of symptoms, Osserman stage, history of myasthenic crisis, concomitant diseases, preoperative pyridostigmine dose, preoperative steroid therapy, operation approach, operation time, presence of thymoma, major postoperative complications.

RESULTSForty-four patients experienced postoperative myasthenic crisis during the first month after thymectomy. Univariate analysis revealed that Osserman stage (RR = 0.0976, P = 0.000), history of myasthenic crisis (RR = 0.2309, P = 0.012), preoperative pyridostigmine dose (RR = 0.4349, P = 0.016), thymoma (RR = 0.0606, P = 0.000), and major postoperative complications (RR = 0.1094, P = 0.000) were significantly related to postoperative myasthenic crisis. Multivariate Logistic regression analysis showed that Osserman stage (IIb + III + IV) (RR = 0.0953, P = 0.000), thymoma (RR = 0.0294, P = 0.000), and major postoperative complications (RR = 0.0424, P = 0.000) independently predict postoperative myasthenic crisis.

CONCLUSIONOsserman stage (IIb + IIIb + IV), thymoma and major postoperative complications are independent predictors of postoperative myasthenic crisis in patients with myasthenia gravis who underwent thymectomy.

Adolescent ; Adult ; Aged ; Child ; Female ; Humans ; Male ; Middle Aged ; Myasthenia Gravis ; surgery ; Postoperative Complications ; Thymectomy ; adverse effects ; Treatment Outcome ; Young Adult

OBJECTIVETo investigate the effects of nucleoside analogues on hepatitis B virus (HBV) in hepatic lymph nodes of hepatitis B related liver transplantation recipients who were hepatitis B surface antigen (HBsAg) positive but negative for serum HBV DNA.

METHODSFrom June 2010 to March 2011, thirty-six cases of hepatitis B related liver transplantation recipients [32 males, 4 females, average age (54 ± 7) years] were divided into drug treatment group and non-drug treatment group according to the utility of nucleoside analogues. Drug treatment group was divided into two subgroups: drug treatment > 3 months group and drug treatment ≤ 3 months group. The hepatic lymph nodes in the hepatoduodenal ligament were taken during the operation of liver transplant. Using nested or semi-nested PCR, HBV DNA and the replicative form HBV cccDNA in hepatic lymph nodes were detected. Data were analyzed by Fisher's exact test.

RESULTSThe positive rate of HBV DNA: the difference was not statistically significant between drug treatment group (72.7%, 16/22) and non-drug treatment group (14/14) (P = 0.062), the difference was not statistically significant between drug treatment > 3 months group (10/14) and drug treatment ≤ 3 months group (6/8) in the subgroups of drug treatment group (P = 1.000). The positive rate of HBV cccDNA: drug treatment group (22.7%, 5/22) was significantly lower than the non-drug treatment (12/14) (P = 0.000), drug treatment > 3 months group (1/14) was significantly lower than drug treatment ≤ 3 months group (4/8) in the subgroups of drug treatment group (P = 0.039).

CONCLUSIONSHepatic lymph nodes maybe one of the extrahepatic HBV reservoirs. Treating with nucleoside analogues more than 3 months can significantly decrease the replication of HBV in hepatic lymph nodes of HBV associated liver transplantation recipients.

Adult ; Aged ; DNA, Viral ; analysis ; Female ; Hepatitis B ; drug therapy ; Hepatitis B virus ; drug effects ; physiology ; Humans ; Liver Transplantation ; Lymph Nodes ; virology ; Male ; Middle Aged ; Nucleosides ; therapeutic use ; Preoperative Care ; Virus Replication

Aged ; Coronary Angiography ; Coronary Restenosis ; diagnostic imaging ; etiology ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Sirolimus ; administration & dosage ; Stents

OBJECTIVETo evaluate the effectiveness and safety of sirolimus-eluting stents (SESs) for treatment of in-stent restenosis (ISR).

METHODSAll 27 patients with ISR and clinical evidence of ischemia had been treated with SESs. Among them, 23 patients had diffuse and complex lesions, and 5 of them received 2 SESs. Clinical and angiographic follow-up were performed for all patients and the results were analyzed.

RESULTSAll stents were implanted successfully. There were no remained stenosis and major in-hospital complications. Average follow-up time was 8.9 +/- 2.1 (5-14) months, with a clinical follow-up rate of 96.3% and angiographic follow-up rate of 92.6%. During the follow-up, there was none of death. One patient had recurrent angina with an angiographic evidence of the proximal edge restenosis of the stent. Mild neointimal hyperplasia in the proximal edge was found in 2 patients, but the stenosis was less than 25%. No late lumen loss was found in other 24 patients. The late lumen loss of the in-stent averaged 0.09 +/- 0.02 mm, and of the distal edge vessel averaged 0.10 +/- 0.03 mm, and of the proximal edge vessel averaged 0.20 +/- 0.06 mm. The rate of target vessel revascularization was 3.8%.

CONCLUSIONThe SES implantation is safe and feasible for the treatment of in-stent restenosis, which could effectively prevent neointimal hyperplasia and recurrent restenosis of the lesion.

Adult ; Aged ; Coronary Angiography ; Coronary Restenosis ; diagnostic imaging ; therapy ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Sirolimus ; administration & dosage ; Stents

Objective To study the expression of special AT-rich sequence-binding protein 1(SATB1) gene and its relationship with SLC22A18 protein expression in astrocytoma.Methods Fifty-six patients with astrocytomas (12 with grade Ⅰ,13 with grade Ⅱ,15 with grade Ⅲ,and 16 with grade Ⅳ),performed surgical excision in our hospitals from September 2006 to June 2010 and from September 2003 to June 2006,were chosen in our study; another 10 brain tissues from patients performed decompression operation resulting from cerebral hernia were selected as the controls.RT-PCR and Western blotting were used to detect the mRNA and protein expressions of SATB1.The SLC22A18 protein expression was detected by immunohistochemical assay.The relations between SLC22A18expressions and SA TB1 levels,and these two and the degree of malignancy were analyzed.Results RT-PCR and Western blotting revealed that positive mRNA and protein expressions were noted in 35patients with astrocytomas; the mRNA and protein expression rate and value of SATB1 in the astrocytoma tissues were significantly different among different grades of tumors (P＜0.05); the higher the malignancy grade,the higher mRNA and protein expression rate and value ofSA TB1; the protein expression value of SA TB1 had a positive correlation with the malignancy grade of tumors (r=0.987,P=0.000).And a few expressions of SA TB1 mRNA and protein were found in the tissues of controls.Immunohistochemical assay indicated that positive protein expression of SLC22A18 was noted in 19 astrocytoma tissues,and the protein expression rate of SLC22A18 in the astrocytoma tissues was significantly different among different grades of tumors (P＜0.05); the higher the malignancy grade,the lower expression of SLC22A18.And the protein expression of SLC22A18 was found in all the tissues of controls.The SATB1 expression rate in the tissues with negative SLC22A18 expression (81.1％) was significantly higher than that in the tissues with positive SLC22A18 expression (26.3％,P＜0.05).Conclusion SATB1 expresses in the astrocytoma tissues,indicating that it may play an important role in the pathogenesis of astrocytoma;up-regulation of SATB1 expression and dysfunction of SLC22A18 may play synergetic roles in the process of carcinogenesis of astrocytoma.

OBJECTIVETo study the feasibility and early results of radical resection of esophageal carcinoma using single-port thoracoscopy combined with laparoscopy.

METHODSFrom March 2010 to December 2010, 6 patients with esophageal carcinoma underwent radical resection by single-port thoracoscopy combined with laparoscopy in the General Hospital of People's Liberation Army. With the patients at a supine position, laparoscopy was performed to complete stomach mobilization and abdominal lymph node dissection. Thoracoscopy was then carried out with the patients lying on the left to mobilize the esophagus and dissect thoracic lymph nodes. Finally, the stomach was pulled into the thoracic cavity via the hiatus of the diaphragm to construct a tube-like stomach, which was then anastomosed to the esophagus using the OrVil system.

RESULTSNo patient was converted to open surgery during the operation. The total operative time ranged from 200 to 320 min. The mean laparoscopic time was 75(range, 45-90) min, and the mean thoracoscopic time 160(120-240) min. The mean intraoperative blood loss was 220(160-300) ml. The mean lymph node retrieval was 12(9-18). No anastomotic fistula, chylothorax, lung infection were found postoperatively.

CONCLUSIONAfter esophageal resection using single-port thoracoscopic and laparoscopy, reconstruction using OrVil system is safe and feasible.

Aged ; Esophageal Neoplasms ; surgery ; Esophagectomy ; methods ; Female ; Humans ; Laparoscopy ; methods ; Male ; Middle Aged ; Thoracoscopy ; methods

OBJECTIVETo investigate the age related changes of the expression of programmed cell death 5 (PDCD5) and caspase 3 in the cochlea of the different age of C57BL/6J mice. The relationship of PDCD5 and caspase 3 and the possible roles in the pathogenesis of presbycusis were also discussed.

METHODSC57 mice of 3, 6, 9 and 12 months old were selected and divided into 4 groups, with 15 mice in each group. Auditory function of C57BL/6J mice was measured by auditory brainstem response (ABR) respectively. The changes of PDCD5 and Caspase 3 protein in the cochlea were detected by immunohistochemistry and Western blotting, the changes of PDCD5 mRNA and caspase 3 mRNA were detected using RT-PCR.

RESULTSWith the increase of age, the mean value for ABR thresholds in response to click, 4 kHz and 8 kHz sound stimulus of C57 mice gradually increased, the expression of PDCD5 and caspase 3 were increased also. At 3 months and 6 months of age in the cochlea of C57, all sorts of expression of PDCD5 and caspase 3 and the expression were enhanced with age. There was an evident expression at 9 months age, but the highest expression was detected at 12 months age. The PDCD5 and Caspase 3 expression were statistically different in each group (P < 0.05). The changes of PDCD5 and caspase 3 mRNA expression were in accordance with that of PDCD5 and Caspase 3 protein expression by the real-time PCR.

CONCLUSIONSThe expression levels of PDCD5 and caspase 3 in the cochlea of C57 mice increase with age, the results suggested that the expression of PDCD5 and caspase 3 might play an important role in the pathogenic mechanism of presbycusis.

Aging ; Animals ; Apoptosis Regulatory Proteins ; metabolism ; Auditory Threshold ; Caspase 3 ; metabolism ; Cochlea ; metabolism ; Mice ; Mice, Inbred C57BL ; Neoplasm Proteins ; metabolism ; Presbycusis ; metabolism ; pathology