Objective To design a method for detecting multileaf collimator (MLC) leaf position accuracy in implementing a static intensity-modulated plan and to analyze the impacts of leaf errors on dose of targets and normal organs.Methods Static intensity-modulated planning for twenty lung cancer cases through dose verification was sorted in an ascending order according to the number of segment,and then the first and the last 10 plans were sorted as the simple plan group and the complex plan group,respectively.These plans were transmitted to a Varian 600CD accelerator and implemented by it.Photos were taken with PV aS500 electronic portal imaging device (EPID) and actual position of leafs was determined by gradient algorithm to calculate the pass rate for leaf verification.MLC files were modified according to examination results and the plans were re-calculated while keeping other parameters unchanged.Thus,difference of targets and normal organs dose distribution before and after the appearance of leaf errors were obtained.Results The dose distribution of most organs after leaf errors were increased or decreased,and the maximum dose of spinal cord in the sixth and thirteen cases exceeded the limit of 45 Gy.In the group of simple plan only the changes of maximum dose to the spinal cord were statistically significant(t =-3.08,P ＜ 0.05),while in the group of the complex plan all changes of D95％ of PGTV and PTV,maximum dose of the spinal cord,V20 of lung and V40 of heart were statistically significant(t =-1.89,-1.99,-2.36,-2.55,-1.85,P ＜ 0.05).Conclusions To ensure the safety and effects,it was necessary to detect leaf position,particularly the complex intensity-modulated planning.Electronic portal imaging devices and treatment planning system could detect leaf positions during the implementation of a plan and obtain the actual dose of targets and normal organs.

Tissue engineering of oral and maxillofacial surgery is a newly subject and animportant branch of tissue engineering. The study is to evaluate fundamental medical ethics principle in the tissue engineering of oral and maxillofacial surgery on the view medical ethcs. Strengthening the ethical education on oral and maxillofacial surgeon and right education on patients are in favor of development of tissue engineering in the oral and maxillofacial surgery.

Objective To analyze MRI findings of the mitochondrial encephalopathy, in order to improve the understanding of this disease. Methods MR findings of 5 patients of clinically proved mitochondrial encephalopathy were retrospectively analyzed. Results Brain parenchymal lesions in all patients were low intensity on T1WI and high signal intensity on T2WI. One patient had bilateral globus pallidus involvement, while involvement of gray matter and white matter were observed in 4 patients. Three patients had enlargement of supratentorial ventricles, 2 patients had cerebellar atrophy and 1 patient had bilateral basal galia calcification. Conclusion MRI can show the intracranial lesions in patients with mitochondrial encephalomyopathy clearly, but accurate diagnosis should depend on clinical data.

Objective To evaluate the diagnostic value of MR in carotid artery involvement using surgery and pathology as gold standard.Methods 37 patients with suspected neck masses underwent MR scan.One radiologist unaware of the pathological results measured the nine indexes as following:axial surrounding angle(AXA),long axis angle(LAA),the adjacent length of tumor long axis(LLA),the tumor long axis length(TLAL),the ratio of the adjacent length of tumor long axis and the tumor long axis length (LLA/TLAL),the perivascular fatty gap,vascular displacement,vascular deformation and magnetic resonance angiography(MRA) evaluation of artery involvement.The comparison of diagnostic value used ROC curve,sensitivity,specificity and accuracy.The cat-egorical data used Fisher orχ2 test,and measurement data used t test.Results Four indexes (AXA,LAA,LLA/TLAL and MRA) had significantly statistical value for evaluating the arterial invasion.The AUC of AXA,LAA,LLA/TLAL were 0.910,0.775 and 0.766 (P <0.05),respectively.Using 145°,61°,0.553 and MRA to indicate invasion for diagnostic value,the sensitivity and spe-cificity of those four indexes were 100.0% and 89.2%,66.7% and 89.2%,100.0% and 59.5%,33.3% and 100.0%,respective-ly.Conclusion The four indexes including AXA,LAA,LLA/TLAL and MRA evaluation of artery involvement have statistic value but with poor stability.MRA had limited diagnostic value although it’s beneficial to observe the carotid artery.

Objective Pathogens from the nosocomial infection have been analyzed by MALDI‐TOF microbial identification system ,to evaluate mass spectrometry analysis advantage and explore the mass spectrometry method .Methods The pathogens have been analyzed by MALDI‐TOF microbial identification system ,by compared with the VITEK‐2 compact detection in the tes‐ting time ,detection rate and the amounts of identified strains .The homology differences have been analyzed by comparison calcula‐tion of common peaks from the fingerprint spectrums .Results Thirty‐one Escherichia coli strains ,28 Klebsiella pneumonia strains and 9 unusual pathogen strains have been identified by MALDI‐TOF MS for only 1 hours .It has more advantages than VITEK‐2 in the testing time and other aspects .Conclusion Nosocomial infection of pathogen shows a point source propagation mode centering on the department .MALDI‐TOF mass spectrometry is able to rapidly and correctly identify the pathogen .MALDI‐TOF microbial i‐dentification system is expected to be the major detecting technique in the field of the pathogen monitor and resistance monitoring a ‐nalysis .

Objective To prepare recombinant plasminogen activator(Pla) protein in E.coli BL21 cells that can be used in studying interactions between Yersinia pestis proteins and immunologic diagnosis of plague.Methods The pla gene was amplified by PCR and cloned into the pET28a expression vector.E.coli BL21 competent cells were transformed with the recombinant vectors, and isopropyl-β-D-thiogalactopyranoside ( IPTG) was added to induce expression of Pla protein. The expressed protein was detected by SDS-PAGE electrophoresis.The inclusion bodies of Pla protein were denatured in 8 mol/L urea, and then refolded using gradient urea solutions.The purified protein was identified by SDS-PAGE electrophoresis and Western blot.Results and Conclusion The constructed expression vector was demonstrated to be correct through agarose gel electrophoresis and sequencing.The recombinant Pla protein was accumulated as an inclusion body in E.coli, and the overexpression product was mainly a target protein, the yield of which was very high.SDS-PAGE purity of the bioactive Pla protein was obtained by denaturing and refolding the inclusion bodies.This study provides a simple and quick method for highly efficient preparation of biologically active Pla protein.

OBJECTIVE To evaluate the value of Epworth sleepiness scale(ESS) combined with home-based portable monitoring(PM) in the diagnosis of patients with obstructive sleep apnea syndrome(OSAS). METHODS Adult OSAS patients who visited Beijing Tongren Hospital and complained of snoring were included in this study. The overnight polysomnography(PSG) and the ESS were completed at the sleep center and the portable multi-channel monitoring was completed within one week. Subjects were divided into two groups according to their apnea hypopnea index(AHI) of PSG: simple snoring or mild OSAS group(AHI<15/h) and moderate-severe group(AHI≥15/h). The ESS score, respiratory disturbance index(RDI) of PM and other parameters were compared and the correlation of AHI with ESS scores, RDI were analyzed. The sensitivity and specificity of ESS score≥9 points, RDI≥15/h in the diagnosis of moderate-severe OSAS were calculated. RESULTS A total of 51 subjects were included in this study with 42 males(82.4％) and 9 females(17.6％). Mean age was(43.8±10.8) years, and the mean body mass index was(27.9±4.5)kg/m2; ESS scored 1-24 points and mean(8.6±5.0) points, 18 cases with ESS score ≥9 points; AHI ranged between 2.5 and 99.8/h with a mean of(37.4±29.8)/h. There were 19(37.3％) and 32(62.7％) patients in snoring-mild group and moderate-severe group, respectively. There was significant difference for ESS scores between the two groups(9.9±5.1 vs 6.6±4.2 points, P<0.05),RDI in moderate-severe OSAS group was significantly higher than that in snoring-mild group[(49.4±23.1)/h vs (6.8±4.5)/h, P<0.001)]. There was a positive correlation between the ESS score and PSG derived AHI(r =0.435, P =0.002); the PM derived RDI were significantly correlated with PSG derived AHI in snoring-mild group(r =0.706, P=0.001), moderate-severe group(r =0.873, P=0.000) and patients with ESS score ≥9 points(r =0.967, P=0.000). At a PSG threshold AHI=15/h, the sensitivity and specificity for ESS score ≥9 points were 45.2％ and 78.9％; the PM derived RDI≥15/h had a sensitivity and specificity of 84.4％ and 84.2％, respectively; the sensitivity and specificity for each individual screening tool along with the combination of ESS and PM were 100.0％ and 100.0％. CONCLUSION ESS combined with PM diagnostic method is a valuable measure for the diagnosis of moderate and severe OSAS patients.

OBJECTIVE To investigate the effects of continuous positive airway pressure (CPAP) on patients with severe obstructive sleep apnea hypopnea syndrome (OSAHS) who underwent the revised uvulopalatopharyngoplasty (UPPP). METHODS 18 cases of severe OSAHS patients (therapy group) were selected for CPAP treatment in the 2nd week of postoperation. The average time of CPAP treatment was 34.3 days. The other 20 cases (control group) onlyunderwent operation. All patients were monitored with PSG before operation and in the 6 months postoperatively. RESULTS Compared with the result of pre-operative PSG, apnea hypopnea index (AHI) and Lowest SaO2 (LSaO_2) was improved (P＜0.001) in two groups. Compared with control group, LSaO_2 of the therapy group in the sixth month postoperatively was improved (P＜0.001), but the decreasing of AHI was not significant (P＞0.05). Contrast to the control group, the length of stage 1 and 2 decreased and that of REM increased. (P＜0.05). CONCLUSION For severe OSAHS patients who underwent uvulopalatopharyngo plasty, CPAP treatment for one month postoperatively could improve the hypoxia of patients, and prolong REM stage, shorten the stage 1 and 2 sleep. CPAP treatment in short time would be helpful for the severe OSAHS patients with revised UPPP.

[Summary] All patients with cholesterol side-chain cleavage enzyme ( P450scc) deficiency that have been reported presented with early adrenal failure. Here we described a 35-year-old male presented with infertility as the only initial presenting complaint. He had received two separate surgeries to remove bilateral testicular masses. We reevaluated the resected tumors and found testicular adrenal rest tumor ( TART) pathology in the resected tumor. We profiled steroid hormones and found significantly elevated ACTH. CT scan revealed bilateral adrenal hyperplasia. Mutation screening identified compound heterozygous mutations (R353W and P432L) in the P450scc encoding gene (CYP11A1). The patient was finally diagnosed as congenital adrenal hyperplasia.

Objective:To construct a chemiluminescense immune quantification assay based one paired mAbs against complexed prostate specific antigen ( c-PSA).Methods:Six week-old female BALB/c mice were immunized with the commercial c-PSA antigen.After serum titer reaching a platform stage ,the spleen was immunized and fused with mouse myeloma cell lines ( Sp2/0 ) .The hybridoma were screened by indirect ELISA ,and eight generated antibodies were paired to obtain a quantitative analysis of the chemical luminescence.Results:7D6 specifically recognized c-PSA,while 1A10 recognized total PSA(t-PSA).And the paired antibody 1A10/7D6 were determined to successfully construct a chemiluminescense immune response quantitative detection method through the detection of c-PSA standard and clinical serum samples .had,positive samples have statistically significant difference ( P<0.000 1 ) with negative samples.And the correlation coefficient R 2 was 0.97 between our c-PSA quantitative results and that of the Siemens c-PSA chemiluminescense immunoassay kit .The detection linear range was 0.1-100 ng/ml,and the sensitivity was 0.005 ng/ml.Conclusion:The paired monoclonal antibodies specifically detecting c-PSA were generated and a c-PSA chemiluminescense immunoassay were developed in this study .The detection capability of our method was comparable with that of the international commercial kit .