Objective To find the best model parameters through Monte Carlo simulation of 6 MV flattening-filter-free (FFF) beams in TrueBeam accelerator, and establish the foundation for the further study of the clinical dosimetry on 6 MV FFF X-rays.Methods Using the BEAMnrc and DOSXYZnrc codes, the percentage depth dose (PDD) and the off-axis ratio (OAR) curves of field ranges from 4 cm ×4 cm to 40 cm × 40 cm were simulated for 6 MV FFF X-ray by adjusting the incident beam energy, radial intensity distribution and angular spread, respectively.The simulation results and measured data were compared, where the optimal Monte Carlo model input parameters were acquired.Results The simulation was most comparable to the measurement when the incident electron energy, full width at half maximum (FWHM) and the spread angle were set as 6.1 MeV, 0.75 mm and 0.9°, respectively.The deviation of 1 mm (position)/1％ (local dose) could be met by the PDD of all tested field sizes and by the OAR when the fields sizes were no larger than 30 cm ×30 cm.The OAR of 40 cm ×40 cm field sizes fulfilled criteria of 1 mm (position)/1.5％ (local dose).Conclusions Monte Carlo simulation agrees well with the measurement and the proposed model parameters, which can be used for further clinical dosimetry studies of 6 MV FFF X-rays.

Objective To investigate the association of chlamydia pneumoniae infection with ankylosing spondylitis (AS).MethodsSerum samples were obtained from 33 AS patients and 22 healthy controls.Enzyme-linked immunosorbent assay (ELISA) was applied to mearsure serum anti-Chlamydia pneumoniae antibodies (IgM/IgG),while immunofluorescence assay (IFA) was used to detect Chlamydia pneumoniae LPS antigen,and polymerase chain reaction (PCR) was used to amplify Chlamydia pneumoniae DNA in peripheral blood cells. Immunohistochemistical technique was applied to examine Chlamydia pneumoniae LPS antigen in synovial tissue from another 9 AS patients who received total hip replacement and 13 patients with comminuted femoral fractures.ResultsThe positive rates of Chlamydia pneumoniae IgM,LPS antigen and chlamydia pneumoniae DNA were higher in AS patients than those in healthy controls (78.8％ vs 22.7％,x2 =16.867,P =0.000; 66.7％ vs 31.8％,x2 =6.431,P =0.011; 33.3％ vs 9.1％,x2 =4.298,P =0.038).Chlamydia pneumoniae DNA positive rate was correlated with erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels (Z =-2.774 and -2.829,P =0.004).In synovial tissues,chlamydial LPS-containing inflammatory cells were observed in 77.8％(7/9) AS patients,while those in fracture patients was 30.8％ ( 4/13 ) ( P =0.08 ).Conclusion Chlamydia pneumoniae infection is common in blood circulation and joint cavity of AS patients and may be associated with the pathogenesis of AS.

BACKGROUND:The reported time of bone marrow mesenchymal stem cel s induced to differentiate into chondrocytes is different. Few studies have observed and compared the cel s’ dynamic transformation during the induction process.
OBJECTIVE:To observe the dynamic differentiation and the mature time of rabbit bone marrow mesenchymal stem cel s which were directional y induced to chondroblasts for 8, 11, 14, 17, 20 days.
METHODS:Bone marrow was aspirated from the femur of New Zeal rabbits, and bone marrow mesenchymal stem cel s were isolated by gradient centrifugation. After cultivation and amplification, bone marrow mesenchymal stem cel s at passage 3 were directional y induced to chondrocytes by the serum-free medium containing transforming growth factor beta-1. The experiments were divided into five groups according to different induction time points:8 days, 11 days, 14 days, 17 days, 20 days. Then cel ular morphology, toluidine blue staining, typeⅡ col agen immunohistochemistry, aggrecan content in induction medium, and chondrogenic differentiation in each group were observed and compared.
RESULTS AND CONCLUSION:Bone marrow mesenchymal stem cel s had apparently transformed in morphology at 8 days of induction, and presented obvious chondrocytes’ morphology at 14 days. The aggrecan in induction medium could be detected at a low level at 4 days, significantly increased at 8 days, and maintained slow increasing at 20 days. At 14 days, the metachromatic particles could be found by toluidine blue staining, and the col agen type Ⅱimmunohistochemistry was significantly positive in cel climbing slice. Experimental findings indicate that, bone marrow mesenchymal stem cel s that are monolayer cultured in a high density can be induced into chondroblasts at the effect of transforming growth factor beta-1 and other factors. There are a few chondroblasts in the early induction process, then cel s begin to have chondrocytes morphology and function after induced for 8 days, and may differentiate to mature chondrocytes at 14 days. In addition, they can keep a high biological activity in the induction process.

Atrial Fibrillation/surgery* ; Cardiac Tamponade/surgery* ; Catheter Ablation/adverse effects* ; Humans ; Radiofrequency Ablation ; Treatment Outcome ; Vena Cava, Superior/surgery*

Objective To evaluate the effect of health education on endemic diseases in Henan province in 2010.Methods According to the requirements of The Education Program for Endemic Diseases Control in 2009 Henan Province,50 counties (districts) of 18 cities with endemic diseases were selected.Referring to the health education questionnaire in the program,knowledge of endemic diseases were asked of pupils and housewives.Intervention effects were evaluated two months after teaching pupils and housewives in counties,towns,villages and schools with the knowledge of endemic diseases and the questionnaire was used.Results Among 50 counties investigated,5523 pupils and 3206 housewives were surveyed in the baseline according to the requirement,and 5417 pupils and 2891 housewives were surveyed for outcome evaluation.The results showed that after this education,pupils' knowledge about endemic diseases increased from 66.31％(10 987/16 569) in the baseline survey to 93.84％(15 250/16 251),the difference have statistical significant(x2 =3877.78,P ＜ 0.01) ; housewives from 67.56％(6133/9078)to 92.67％(8037/8673),the difference have statistical significant(x2 =1736.33,P ＜ 0.01).After the education,the pupils' knowledge about the iodine deficiency disorders,drinking-water-borne fluorosis and arsenic poisning,coal-burning-borne fluorosis increased from 70.15％ (6263/8928),62.29％(4423/7101),42.96％ (185/270),68.52％ (116/270) to 94.19％ (8344/8859),93.05％ (6376/6852),99.63％ (261/270),96.67％ (269/270),the difference have statistical significant (x2 =1749.85,1939.26,211.83,74.43,all P ＜ 0.01),housewives' knowledge about the iodine shortage diseases,drinking-water-borne fluorosis,the endemic fluorine,the arsenic poisoning increased from 73.27％ (3330/4545),62.79％ (2677/4263,30.37％ (85/135),62.96％(41/135) to 93.96％(4228/4500),91.08％(3555/3903),97.04％(123/135),91.11％(131/135),the difference have statistical significant (x2 =751.03,924.65,129.75,30.23,all P ＜ 0.01).Conclusions Health education intervention has a marked effect in increasing the peoples' knowledge of endemic diseases.Therefore health education should be enhanced in the future.

Chylothorax is an uncommon disease where fatty fluid accumulates within the chest cavity. Conservative management, including repeated thoracentesis or pleurodesis, seems to be suitable to most cases. Herein, we present a case of efficacious pleurodesis by intrapleural injection of Sapylin, a streptococcus preparation, for the treatment of chylothorax. A 52-year-old non-smoking female farmer was diagnosed as idiopathic chylothorax after we ruled out possible causes including chest trauma, lymphoma, lung cancer, filariasis, tuberculosis, and etc. Two-time intra-thoracic injection of 3 Klinische Einheit (KE) Sapylin achieved rapid and effective control of chylothorax with no severe side effects. Sapylin may facilitate pleurodesis by producing a strong inflammatory response.
Bacterial Vaccines ; therapeutic use ; Biological Products ; therapeutic use ; Chylothorax ; drug therapy ; pathology ; Female ; Humans ; Middle Aged ; Streptococcus ; chemistry ; Tomography, X-Ray Computed

OBJECTIVE: We wanted to evaluate the image quality and diagnostic value of 64-slice dual-source computed tomography (DSCT) coronary angiography in patients with atrial fibrillation (Afib). MATERIALS AND METHODS: The coronary arteries of 22 Afib patients seen on DSCT were classified into 15 segments and the imaging quality (excellent, good, moderate and poor) and significant stenoses (> or = 50%) were evaluated by two radiologists who were blinded to the conventional coronary angiography (CAG) results. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for detecting important coronary artery stenosis were calculated. McNemar test was used to determine any significant difference between DSCT and CAG, and Cohen's Kappa statistics were calculated for the intermodality and interobserver agreement. RESULTS: The mean heart rate was 89 +/- 8.3 bpm (range: 80-118 bpm). A range from 250 msec to 300 msec within the RR interval was the optimal reconstruction interval for the patients with Afib. The respective overall sensitivity, specificity, PPV and NPV values were 74%, 97%, 81% and 96% for reader 1 and 72%, 98%, 85% and 96% for reader 2. No significant difference between DSCT and CAG was found for detecting a significant stenosis (reader 1, p = 1.0; reader 2, p = 0.727). Cohen's Kappa statistics demonstrated good intermodality and interobserver agreement. CONCLUSION: 64-slice DSCT coronary angiography provides good image quality in patients with atrial fibrillation without the need for controlling the heart rate. DSCT can be used for ruling out significant stenosis in patients with atrial fibrillation with its high NPV for detecting in important stenosis.
Aged ; Aged, 80 and over ; Algorithms ; Atrial Fibrillation/*radiography ; Contrast Media/diagnostic use ; Coronary Angiography/*methods ; Coronary Disease/*radiography ; Echocardiography ; Electrocardiography ; Female ; Heart Rate ; Humans ; Iohexol/analogs & derivatives/diagnostic use ; Male ; Middle Aged ; Prospective Studies ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted ; Tomography, X-Ray Computed/*methods

OBJECTIVETo compare the roles of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) using the liver acquisition with volume acceleration(LAVA) sequence and diffusion-weighted imaging(DWI) in the detection of hepatic metastases sized ≤3 cm.

METHODSWe retrospectively analyzed the MRI data of 16 patients with hepatic metastases. All the sequences used included T1WI, T2WI,3D-LAVA, and DWI (b value=500 s/mm(2)). All patients were divided into two groups based on the sequences: group A (T1WI, T2WI, and 3D-LAVA enhanced MR) and group B(T1WI,T2WI and DWI). The hepatic metastases were evaluated by analyzing the receiver operating characteristic (ROC) curves.

RESULTSA total of 39 hepatic metastatic lesions were identified. The sensitivity, specificity, Youden index and the area under the ROC curve (AUC) were 97.4%, 88.2%, 0.856, and 0.944 in group A and 82.1%, 91.2%, 0.733, and 0.834 in group B. The ROC curves (p=0.040) and Youden index(p=0.043) in group A were significantly larger than in group B.

CONCLUSIONGadolinium-EOB-DTPA-enhanced MRI has higher accuracy than DWI in the detection of small metastases.

Adult ; Aged ; Aged, 80 and over ; Diffusion Magnetic Resonance Imaging ; Female ; Follow-Up Studies ; Humans ; Liver Neoplasms ; diagnosis ; secondary ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Retrospective Studies

Twenty-four soil samples of eight ecosystem-types around the Yellow River source area were investigated for the number and specific composition of soil dematiaceous hyphomycetes by dilution plate technique. And then the co-relationship between genus species of soil dematiaceous hyphomycetes and ecosystem-types was analyzed. The results show that the amount and species distribution of soil dematiaceous hyphomycetes had an obvious variability in different ecosystem-types, and that the dominant genus species varied in the eight ecosystem-types studied, with Cladosporium being the dominant genus in seven of the eight ecosystem-types except wetland. The index of species diversity varied in different ecosystem-types. The niche breadth analysis showed that Cladosporium had the highest niche breadth and distributed in all ecosystem-types, while the genera with a narrow niche breadth distributed only in a few ecosystem-types. The results of niche overlap index analysis indicated that Stachybotrys and Torula, Doratomyces and Scolecobasidium, Cladosporium and Chrysosporium had a higher niche overlap, whereas Arthrinium and Gliomastix, Phialophora and Doratomyces, Oidiodendron and Ulocladium had no niche overlap.
China ; Ecosystem ; Fresh Water ; microbiology ; Mitosporic Fungi ; classification ; isolation & purification ; Soil Microbiology ; Species Specificity