BACKGROUND:C2 transpedicle screw fixation for Hangman fractures has been paid more attention due to reliability and no loss of physiological function.However,there are lacks of biomechanical evidences for indication treatment because the fixation is single segmental.OBJECTIVE:To investigate the biomechanical stability of C2 transpedicle screw fixation for Hangman fractures.DESIGN,TIME and SEITING:This was a contrast study which was performed at the General Key Laboratory of Biomechanics,First Military Medical University of Chinese PLA from May to August 2004.MATERIALS:AO-universal titanium alloy transpedicle screw of 18 25 mm in length and 3.5 mm in diameter was adopted in this study.Six fresh C1-C4 cervical vetebrae samples were ordiually made into type Ⅰ,ⅡA,and Ⅱ Hangman fracture models.METHODS:After transpedicle screw fixation.Hangman fracture models were measured by non-destroyed style with spinal anterior flexion/posterior extension,left/right lateral curvature,and left/right axial direction.Loading/unlonding circulation was performed three times during each testing.Kinematics indicators were measured on the 3rd circulation.MAIN OUTCOME MEASURES:Spinal motor images at zero load and maximal load were obtained with laser photoscanning(0.1% in precision),and the corresponding systematic software was adopted to calculate 3D range of movement.RESULTS:The relative stability of type Ⅰ Hangman fracture models after C2 transpedicle screw fixation was 100.62%(inflexion),96.91%(posterior extension),99.19%(lateral curvature),and 97.12%(rotation)as compared to control group (P＞0.05).The relative stability of type Ⅱ Hangman fracture models after C2 transpedicle screw fixation was 47.84%(inflexion),21.29%(posterior extension),65.98%(lateral curvature),and 41.69%(rotation)as compared to control group (P＜0.05).CONCLUSION:Biochemical evaluation suggests that type Ⅰ and Ⅱ A Hangman fractures do fit for C2 transpedicle screw fixation,and the fixation may generate well physiological fixation or stability.However,stability of type Ⅱ Hangman fracture is poor,so it is not suitably adopted single transpedicle screw fixation.

BACKGROUND: Decompression-internal fixation is needed in the treatment of atlantoaxial dislocation accompanying with spinal compression caused by cranium-neck junction area malformation and other diseases.Different internal fixation methods are chosen according to different conditions, including anterior atlantoaxial internal fixation, posterior atlantoaxial internal fixation or occipitocervical internal fixation. Transoralpharyngeal atlantoaxial plate internal fixation is a method for atlantoaxial anterior fixation. It is developed recently and used for difficult and complicated atlantoaxial dislocation induced by congenital disease, trauma or rheumatoid arthritis.OBJECTIVE: To probe into the clinical application of transoralpharyngeal atlantoaxial reduction plate system in the atlantoaxial dislocation caused by obsolete odontoid fracture.DESIGN: Single Sample observation SETTING: Department of Orthopaedics, Guangzhou General Hospital of Guangzhou Military Medical University of Chinese PLA PARTICIPANTS: Twelve patients with atlantoaxial dislocation caused by obsolete odontoid fracture were selected in the Department of Orthopaedics, General Hospital of Guangzhou Military Medical University of Chinese PLA from January 2003 to October 2005. Among them, 7 were male and 5 were female, they were aged 47 years on average ranging from 36 to 59 years. The mean injured time was 19 months ranging from 4.5 to 36 months; 6 patients were graded as C degree, 3 as D degree and 3 as E degree in Frank gradation.METHODS: Twelve obsolete odontoid fracture caused by atlantoaxial dislocation underwent transoralpharyngeal anterior decompression. Transoralpharyngeal atlantoaxial reduction plate system was used in reduction and fixation. Autogeneic ilium was implanted into bilateral articulatio atlantoepistrophica.MAIN OUTCOME MEASURES: ① Frank gradation of patients at the 4th week after operation. ② whether the internal fixation is loose or not after operationRESULTS: ①Frank gradation at the 4th week after operation: Among the 6 patients who were primarily graded as C degree, 4 patients improved to be E degree and 2 patients D degree; Three patients who were primarily graded as D degree all improved to be E degree; Patients who were primarily graded as E degree did not changed. ② Except for one patient who suffered dislocation again for loosening of screw caused by tumble, the other patients had firm fixation, ideal fusion and satisfying spinal decompression.CONCLUSION: Transoralpharyngeal atlantoaxial reduction plate system finishes atlantoaxial reduction and fixation once. It avoids conducting posterior fusion fixation operation after anterior decompression. It also avoids fetal injury for spinal cord caused by extreme atlantoaxial unsteadiness in the process of movement and turning over.

OBJECTIVETo investigate the pathogenic factors of human cytomegalovirus (HCMV) infections.

METHODSTotally 36 serum samples were obtained from early pregnant woman and examined with ELISA for anti-HCMV antibody IgG and IgM. After artificial abortion,chorionic villus and decidua were also examined with polymerase chain reaction (PCR) for HCMV-DNA. When the results of PCR were positive, pathological changes of these chorionic villus and decidua were analyzed.

RESULTSThe results showed that only 10 samples were PCR positive while IgG and/or IgM antibody to HCMV was positive. After infection with HCMV, different changes occurred in chorionic villus and decidual trophoblastic cells placental villus were hyperplasic and decidua cells degenerated and necrotized followed by lymphocytes infiltration.

CONCLUSIONThese pathological changes may be one of pathogenic factors of HCMV.

Adult ; Antibodies, Viral ; blood ; Chorionic Villi ; pathology ; virology ; Cytomegalovirus ; genetics ; immunology ; isolation & purification ; Cytomegalovirus Infections ; pathology ; DNA, Viral ; analysis ; Decidua ; pathology ; virology ; Female ; Humans ; Immunoglobulin G ; blood ; Immunoglobulin M ; blood ; Pregnancy ; Pregnancy Complications, Infectious ; pathology ; virology

OBJECTIVETo design a tool for evaluating the sound transmission function of ossicular prosthesis and explore the impacts of ossicular prosthesis bead area and the effects of the mass of ossicular prosthesis on the sound transmission function in mechanical middle ear model.

METHODSTwo latex membranes were used to represent the tympanic membrane and oval window membrane. The ossicular prosthesis was fitted between the artificial tympanic membrane and oval window membrane during the test. Pure tune signals were used to stimulate the vibration of tympanic membrane. The vibration of oval window membrane was recorded by a laser Doppler vibrometer. The ossicular transmission function was evaluated by comparing the vibration velocities of oval window membrane. Two groups of titanium ossicular prosthesis with different head area and mass respectively were fitted into a mechanical middle ear model to evaluate their sound transmission functions.

RESULTSThe feeling threshold curve of mechanical middle ear model (MMEM) was similar to the hearing threshold curve of normal person. The transmission function of the prosthesis with small head area was better than that of prostheses with large head area at frequencies 1500-4000 Hz. The small-massed prostheses functioned better at higher frequencies and the large-massed prostheses functioned better at lower frequencies. But small-massed prostheses functioned better as a whole.

CONCLUSIONSThe MMEM was an idea tool to evaluate the transmission functions of different ossicular prostheses. Both the head area and prosthesis mass had an influence on the transmission function of ossicular prosthesis. So while designing the ossicular prosthesis or performing ossiculoplasty, both the head area and prosthesis mass should he taken into consideration.

Acoustic Impedance Tests ; Acoustics ; Ear, Middle ; anatomy & histology ; Models, Anatomic ; Ossicular Prosthesis ; Prosthesis Design

Objective To evaluate the biomechanical characteristics and the clinical advantage of transoral atlantoaxial reduction plate(TARP)Ⅲ.Methods Design of TARP-Ⅲ was based on TARP-Ⅱ.The screw hole in the axis was moved 1-2 mm upwards and inwards in a plate which turned a vertebral screw into a pedicle screw or an articular process screw.A polyaxial self-lock ring and polyaxial guiding drill were added to the crew hole of the plate.Finally,the withdrawal resist ence force of the three axis screws was tested and TARP-Ⅲ was used in 44 patients with complicated irreducible atlantoaxial dislocation.The axis was fixed with the pedicle screw or the articular process screw.Results The maximum withdrawal resist ence force of the anterior pedicle screw,the articular process screw and the vertebral screw in the axis was(593.1 ± 97.8)N,(469.9 ± 73.3)N and(395.2 ± 75.1)N respectively,with statistical difference between groups among three fixation methods(P ＜ 0.05).All 44 patients were followed up for 5-38 months(average 18 months),which showed complete anatomic reduction in 36 patients and appropriate anatomic reduction in eight,with basic correction of the angles between the brain stem and the spinal cord and sufficient decompression of the spinal cord.The decompression rate of the cervical spinal cord was average 88.2% according to the Yin evaluating method of cervical cord decompression.The improvement rate of spinal cord function was average 76.6% according to Japanese Orthopaedic Association(JOA)score.Conclusion With the design of polyaxial self-lock mechanism,TARP-Ⅲ with the pedicle screw or the articular process screw surpasses TARP-Ⅱ with vertebral screw in aspect of biomechanics.

Objective To explore the relationship between immune and pathogenesis of amyotrophic lateral sclerosis (ALS) in the investigation of neurofilaments phosphorylation and ultrastructure features in spinal cord ventral horn motor neuron injury mediated by immune.Methods Using transmission electron microscope,we studied the uhrastructure features of abnormal accumulations of neurofilaments (NF) in motoneuron of the spinal cord ventral horn,and immunohistochemically investigated neurofilaments phosphorylation.Results Electron microscope found that there was abnormal accumulation of interwoven NFs in motor neuronal perikarya and proximal axons.Immunohistochemical study revealed that the SMI-32 immunoreactive positive neurons (12.00?1.05),compared with control (18.00?1.83),were reduced (P

Objective To develop a double antibody sandwich ELISA assay for quantitative determination of recombinant human interferon α1b.Methods Mouse monoclonal antibodies with different binding site on rIFN-α1b were screened to select optimized candidates as coating and HRP-labeled index antibodies respectively.And a double antibodies sandwich ELISA was assembled; the reliable lower detection limit,specificity,accuracy and reproducibility were evaluated and validated.Results The quantitative sandwich ELISA had a reliable lower detection limit of 10 ng/ml,with a liner detection range 10-100 ng/ml (R2 =0.992),variation coefficient inter-plates is less than 10％.Conclusion The developed sandwich ELISA was a sensitive and specific,accuracy and reproducibility method for quantitative determination of recombinant human interferon αt1b in final product.

OBJECTIVETo investigate outcomes after transanal endoscopic microsurgery (TEM) for early rectal cancer, identify risk factors associated with recurrence, and explore the indication of TEM for rectal cancer.

METHODSSixty patients with rectal cancer undergoing TEM between June 2006 and June 2009 in the Provincial Qianfoshan Hospital of Shandong University were included in this study and data were retrospectively analyzed.

RESULTSThere were 12 patients with pTis rectal cancer, 38 with pT1 and 10 with pT2. All the lesions were excised en bloc by full-thickness TEM. No positive resection margins were reported. The operative time was(65.0 ± 36.5) min. Estimated blood loss was (10.5 ± 5.8) ml and hospital stay was(4.5 ± 2.7) d. No perioperative mortality and complications occurred. The median follow-up was 28.5(range, 12-48) months. No recurrence developed in pTis lesions. There was significant difference in local recurrence rate between pT1 and pT2(2.6% vs. 40.0%, P<0.05). The recurrence rate in lesions larger than 3 cm in diameter(19.0%, 4/21) was significantly higher than that in lesions smaller than 3 cm in diameter (2.6%, 1/39) (P<0.05). Multivariate analysis showed that depth of tumour invasion(T stage) and tumour size were independently associated with recurrence after TEM.

CONCLUSIONLocal excision by TEM is oncologically safe and effective for pTis and pT1 rectal cancers and early lesions smaller than 3 cm in diameter.

Adult ; Aged ; Anal Canal ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Microsurgery ; methods ; Middle Aged ; Neoplasm Recurrence, Local ; etiology ; Proctoscopy ; methods ; Rectal Neoplasms ; surgery ; Retrospective Studies ; Risk Factors ; Treatment Outcome

OBJECTIVETo investigate the ion channel genes related with the genesis and development of heart failure after myocardial infarction through analyzing the differential gene expressions in non-infarcted myocardial tissues of post-myocardial infarction heart failure (PIHF) rat model, and that of normal rat, and the bio-informatics Stc-GO analysis on them.

METHODSRat model of PIHF was established by left anterior descending coronary artery ligation in six SD rats, and a control group with six sham-operative rats was set. Myocardial samples were taken in two batches from them (three rats in each group) at the heart failure formation stage and the stable stage (10 days and 8 weeks after operation) respectively. Total RNA extraction, probe preparation with reverse transcription, hybridization with double-channel cDNA microarray of rat's ion channel genes, and computerized differential gene expression screening were conducted, and Stc-GO functional clustering analysis was performed on the outcomes obtained to search out the GO sort of significance in them.

RESULTSAt 10 days after operation, 319 common differential expressed genes were found from the 746 target genes, all of them were up-regulated. At 8 weeks after operation, in the 276 differential expressed genes, 274 were up-regulated while the other two down-regulated. The up-regulated genes were those concerning receptors of various hormones, cytokines, neuro-hormones, growth factors and nuclear receptor, protein phosphorylase, G protein, various ion channels mediated by ligand or voltage, transport protein, receptor interfering protein, etc. The down-regulated genes concerning the potassium channel and transport protein, etc. Stc-GO analysis found that the six genes concerning adrenergic receptor kinase beta 1 (betaARK1), amiloride-sensitive cation channel 2 neuronal (Accn2), voltage-dependent calcium ion channel gamma subunit 1 (Cacng1), cyclic nucleotide gated channel alpha 1 (Cnga1), Glutamate receptor ionotropic kainite 2 (Grik 2) and neurotrophic tyrosine kinase receptor type 2 (Ntrk 2), were all the significantly up-regulated differential genes of the model group related with the sham-operative group, and all showed a down-regulating trend as time goes on, and four genes in them were validated by the RT-PCR test.

CONCLUSIONIon channel genes concerning Accn2, Grik2, Ntrk2 and Cacng1 were up-regulated in PIHF, and its mechanism is waiting for further study.

Animals ; Heart Failure ; etiology ; genetics ; metabolism ; Ion Channels ; metabolism ; Male ; Myocardial Infarction ; complications ; genetics ; metabolism ; Oligonucleotide Array Sequence Analysis ; Rats ; Rats, Sprague-Dawley ; Transcriptome

OBJECTIVETo investigate the treatment for traumatic intervertebrae disk herniation in cervical thoracic junction.

METHODSFrom 2003 to 2008, there were 10 patients with trautimatic intervertebral disk herniation in cervical thoracic junction, which included 6 males and 4 females, aged from 23 to 66 years (means 41.5 years). All of them were performed through the transforminal approach combined with internal fixation. After operation all patient underwent hyperbaric oxygen treatment. The function of spine was evaluated by JOA score system.

RESULTSAll patients were followed up for 8 to 16 months(means 13 months). All patients got recovery of spine function to some extent except one case with complete spine damaged. The JOA scores was improved from (8 +/- 3) before operation to (15 +/- 2) after operation.

CONCLUSIONEarly and effective treatment by transforminal operation could be helpful for the recovery of spine function.

Adult ; Aged ; Cervical Vertebrae ; injuries ; surgery ; Female ; Fracture Fixation, Internal ; methods ; Humans ; Intervertebral Disc Displacement ; surgery ; Male ; Middle Aged ; Thoracic Vertebrae ; injuries ; surgery