This study aims to gain insight into the DNA-specific recognition mechanism of c-Myb transcription factor during the regulation of cell early differentiation and proliferation. Therefore, we chose the chicken myeloid gene, mitochondrial import protein 1 (mim-1), as a target to study the binding specificity between potential dual-Myb-binding sites. The c-Myb-binding site in mim-1 is a pseudo-palindromic sequence AACGGTT, which contains two AACNG consensuses. Simulation studies in different biological scenarios revealed that c-Myb binding with mim-1 in the forward strand (complex F) ismore stable than that inthereverse strand (complex R). The principal component analysis (PCA) dynamics trajectory analyses suggested an opening motion of the recognition helices of R2 and R3 (R2R3), resulting in the dissociation of DNA from c-Myb in complex R at 330 K, triggered by the reduced electrostatic potential on the surface of R2R3. Furthermore, the DNA confirmation and hydrogen-bond interaction analyses indicated that the major groove width of DNA increased in complex R, which affected on the hydrogen-bond formation ability between R2R3 and DNA, and directly resulted in the dissociation of DNA from R2R3. The steered molecular dynamics (SMD) simulation studies also suggested that the electrostatic potential, major groove width, and hydrogen bonds made major contribution to the DNA‍-specific recognition. In vitro trials confirmed the simulation results that c-Myb specifically bound to mim-1 in the forward strand. This study indicates that the three-dimensional (3D) structure features play an important role in the DNA-specific recognition mechanism by c-Myb besides the AACNG consensuses, which is beneficial to understanding the cell early differentiation and proliferation regulated by c-Myb, as well as the prediction of novel c-Myb-binding motifs in tumorigenesis.
Molecular Dynamics Simulation ; Consensus ; DNA ; Hydrogen

Objective:To analyze the features of the connective tissue associated interstitial lung disease (CTD-ILD) by high resolution computed tomography (HRCT).Methods:A total of 127 patients with CTD-ILD,who were diagnosed by clinic laboratory examination and pathology in Xiangya Hospital of Central South University form September 2013 to September 2015,were enrolled for this study.Their lung features of HRCT imaging were retrospectively analyzed.Results:The classifications for 127 patients were as follows:36 cases of rheumatoid arthritis (28.3%),34 cases of dermatomyositis and polymyositis (26.8%),31 cases of systemic sclerosis (24.4%),18 cases of Sj(o)gren syndrome (14.2%),7 cases of mixed connective tissue disease (5.5%),and 1 cases of systemic lupus erythematosus (0.8%).According to the features of HRCT imaging,the patients were divided as follows:77 cases (60.6%) ofnonspecific interstitial pneumonia (NSIP),46 cases (36.2%) of usual interstitial pneumonia (UIP),2 cases (1.6%) of lymphocytic interstitial pneumonia (LIP),1 case (0.8%) of cryptogenic interstitial pneumonia (COP),and 1 case (0.8%) of acute interstitial pneumonia (AIP).The HRCT findings for 36 cases of rheumatoid arthritis associated interstitial lung disease were UIP (24 cases,66.7%) and NSIP (12 cases,33.3%);the HRCT findings for 34 cases of dermatomyositis and polymyositis associated interstitial lung disease were NSIP (32 cases,94.1%),UIP (1 case,2.9%) and COP (1 case,2.9%);the HRCT findings for 31 cases of systemic sclerosis associated interstitial lung disease were NSIP (21 cases,67.8%),UIP.(9 cases,29%),LIP(1 case,3.2%);the HRCT findings for 18 cases of Sj(o)gren syndrome associated interstitial lung disease were NSIP (9 cases,50.0%),UIP (8 cases,44.4%),LIP (1 case,5.6%);the HRCT findings for 7 cases of mixed connective tissue disease associated interstitial lung disease were UIP (4 cases,57.1%),NSIP (3 cases,42.9%).SLE-ILD was rare,with only 1 case of AIP.Conclusion:Different types of CTD-ILD patients display relatively unique manifestation of HRCT.

OBJECTIVE: To determine whether an optimal blood suppression inversion time (BSP TI) can boost arterial visibility and whether the optimal BSP TI is related to breathing rate (BR) and heart rate (HR) for hypertension subjects in spatial labeling with multiple inversion pulses (SLEEK). MATERIALS AND METHODS: This prospective study included 10 volunteers and 93 consecutive hypertension patients who had undergone SLEEK at 1.5T MRI system. Firstly, suitable BSP TIs for displaying clearly renal artery were determined in 10 volunteers. Secondly, non-contrast enhanced magnetic resonance angiography with the suitable BSP TIs were performed on those hypertension patients. Then, renal artery was evaluated and an optimal BSP TI to increase arterial visibility was determined for each patient. Patients' BRs and HRs were recorded and their relationships with the optimal BSP TI were analyzed. RESULTS: The optimal BSP TI was negatively correlated with BR (r1 = -0.536, P1 < 0.001; and r2 = -0.535, P2 < 0.001) and HR (r1 = -0.432, P1 = 0.001; and r2 = -0.419, P2 = 0.001) for 2 readers (kappa = 0.93). For improving renal arterial visibility, BSP TI = 800 ms could be applied as the optimal BSP TI when the 95% confidence interval were 17-19/min (BR1) and 74-82 bpm (HR1) for reader#1 and 17-19/min (BR2) and 74-83 bpm (HR2) for reader#2; BSP TI = 1100 ms while 14-15/min (BR1, 2) and 71-76 bpm (HR1, 2) for both readers; and BSP TI = 1400 ms when 13-16/min (BR1) and 63-68 bpm (HR1) for reader#1 and 14-15/min (BR2) and 64-70 bpm (HR2) for reader#2. CONCLUSION: In SLEEK, BSP TI is affected by patients' BRs and HRs. Adopting the optimal BSP TI based on BR and HR can improve the renal arterial visibility and consequently the working efficiency.
Adult ; Female ; *Heart Rate ; Humans ; Hypertension/pathology ; Kidney/*blood supply ; Magnetic Resonance Angiography/*methods ; Male ; Middle Aged ; Prospective Studies ; Renal Artery/*physiology ; *Respiratory Rate

OBJECTIVE: To evaluate the value of multi-slice CT angiography (MSCTA) in the diagnosis of super mesenteric artery (SMA) and super mesenteric vein (SMV), and discuss the 3D reconstruction method for detecting mesenteric vessel lesions. METHODS: Thirty-three patients suffering from mesenteric vessel diseases were analyzed. There were 14 SMA lesions, including 9 thromboses, 3 dissecting aneurysms, 1 pseudoaneurysm, and 1 malrotation. There were 19 SMV thromboses. The 3D reconstruction included volume rendering (VR), maximum intensity projection (MIP), and multi-planner reformation (MPR). RESULTS: The lesions appeared clear by MSCTA in the 33 patients. The SMA thrombosis was shown clear in the MIP in all 9 patients, and only 4 of them were detected in the VR. There was significant difference between MIP andVR in detecting SMA thrombosis (P=0.0294). Three dissecting aneurysms were best shown in the MPR; 1 pseudoaneurysm and 1 malrotation were clearly manifested in the VR. The thrombosis of SMV was clearly shown by both MIP and MPR in all 19 patients. Collateral vessels were clearly shown in the MIP in 12 patients; the collateral vessels were detected by VR only in 5, and the other 7 failed to show the collateral vessels. There was significant difference between the MIP and the VR in showing lateral collateral vessels (P=0.0046). CONCLUSION Both lesions of SMA and SMV can be detected by MSCTA. MIP is an ideal reconstruction method for SMA thrombosis and collateral vessels around the SMV.
Aneurysm, Dissecting ; diagnosis ; Angiography ; Humans ; Mesenteric Arteries ; pathology ; Mesenteric Veins ; pathology ; Thrombosis ; diagnosis ; Tomography, X-Ray Computed

Objective To evaluate the teaching effects of case introduced method based on picture archiving and communication system (PACS) system in medical imaging course.Methods Totally 148 students (2009 grade) majored in five-year clinical medicine from Xiangya Medical College were divided into 10 groups; the 10 groups were taken randomly as control group (n=75) and experimental group (n=73).Control group used traditional teaching methods (film teaching) while experimental group used case introduced method based on PACS system.Effects of teaching between were evaluated by questionnaire and test.x2 test was used to compare students' theoretical test scores,with α level =0.05.Results Based on results of questionnaires,more students in experimental group than in control group hold that case introduced method based on PACS system can achieve the purpose of teaching,improve interests in learning,and strengthen the mastery of knowledge.Test scores showed that the percentage of students scored 90-100 and 80-89 (respectively 14％,75％) in experimental group was significantly higher than that in control group (respectively 5％,66％) (x2 =17.932,P=0.000).Conclusions Application of case introduced method based on PACS system in medical imaging course not only improve students' motivation to learn and their clinical ability,but also allow teachers to find and correct shortcomings of students timely,therefore,it is worth promoting.

Objective To investigate the teaching effect of‘index’teaching method used in practical teaching of the medical imaging.Methods A total of 178 medical undergraduates were selected this study,113 clinical medical students using‘index’teaching method were taken as experimental group while others 65 anesthesia medical students using traditional teaching method as control group.The teaching effect of‘index’teaching method was evaluated quantitatively and qualitatively by practical test and questionnaire survey.Results The test scors of experimental group were(80.3±16.5),obviously higher than those of(71.3±25.8)in control group(P＜0.05),especially instudents with low scores.Conclusion The new teaching method had obvious advantages in culturing the thinking of imaging diagnosis and in improving the ability to solve clinical practical problems,the‘index’teaching method was more effective than traditional teaching method.

OBJECTIVE: To explore the degree, mechanism and clinical significance of three-dimensional tumor microvascular architecture phenotype heterogeneity (3D-TMAPH) in non-small cell carcinoma (NSCLC). METHODS: Twenty-one samples of solitary pulmonary nodules were collected integrally. To establish two-dimensional tumor microvascular architecture phenotype (2D-TMAP) and three-dimensional tumor microvascular architecture phenotype (3D-TMAP), five layers of each nodule were selected and embedded in paraffin. Test indices included the expressions of vascular endothelial growth factor (VEGF), proliferating cell nuclear antigen (PCNA), EphB4, ephfinB2 and microvascular density marked by anti-CD34 (CD34-MVD). The degrees of 3D-TMAPH were evaluated by the coefficient of variation and extend of heterogeneity. Spearman rank correlation analysis was used to investigate the relationships between 2D-TMAP, 3D-TMAP and clinicopathological features. RESULTS: 3D-TMAPH showed that 2D-TMAP heterogeneity was expressed in the tissues of NSCLC. The heterogeneities in the malignant nodules were significantly higher than those in the active inflammatory nodules and tubercular nodules. In addition, different degrees of heterogeneity of CD34-MVD and PCNA were found in NSCLC tissues. The coefficients of variation of CD34- MVD and PCNA were positively related to the degree of differentiation (all P<0.05), but not related to the P-TNM stages, histological type or lymphatic metastasis (all P>0.05). The level of heterogeneity of various expression indexes (ephrinB2, EphB4, VEGF) in NSCLC tissues were inconsistent, but there were no significant differences in heterogeneity in NSCLC tissues with different histological types (P>0.05). CONCLUSION 3D-TMAPH exists widely in the microenvironment during the genesis and development of NSCLC and has a significant impact on its biological complexity.
Adult ; Aged ; Capillaries ; ultrastructure ; Carcinoma, Non-Small-Cell Lung ; blood supply ; Ephrin-B2 ; metabolism ; Female ; Humans ; Lung Neoplasms ; blood supply ; Male ; Middle Aged ; Neovascularization, Pathologic ; pathology ; Phenotype ; Proliferating Cell Nuclear Antigen ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism

Experience-oriented teaching approach was introduced into the bilingual course of medical imaging in order to improve the teaching effect.This approach was performed through English literature translation activities and scene-teaching.Meanwhile it points out that this approach has particular advantages in stimulating students' interest and initiative in study.

The authors use the method of combination of PBL teaching and clinic practicing in practical teaching of the digestive system medical imaging.The process is divided in four steps.This method can greatly improve the learning efficiency of the students and get good teaching result.

Objective To develop a new method for describe features of inflow of left ventricle(LV) from color Doppler image by color singular value,and evaluat the value of color singular value in assessment of diastolic dysfunction. Methods Patients with diastolic dysfunction of LV including myocardial infarction (n = 37), angina( n = 35), cardiomyopathy( n = 45) and hypertension ( n =46) were selected and 30 healthy cases as control. CV and AV from color singular value of LV inflow was displayed and calculated automatically by an analyzing system developed in our laboratory. Results Compared with that of control (CV:2.40 0.22 and AV: -0.25 0.05), the absolute value of CV(1.67-1.90 in average)and AV( - 0. 11～-0. 20 in average) from color singular value were decreased significantly( P <0. 001) in groupsof myocardial infarction, angina, cardiomyopathy and hypertension. Conclusions Singular value can be applied to detect color differences in LV inflow from color Doppler signals. Changes of singular value within the diastolic inflow under pathological conditions may reflect the diastolic dysfunction of LV.