Objective To investigate the optimum threshold value of tracking and triggering technique (surestart) in imaging of coronary artery by 16-slice row CT. Methods 60 patients enrolled in the enhanced scan of coronary artery imaging were divided into 2 groups (group a : heart rate 70 beats/per minute ). The quality of images collected under different threshold value and heart rate was compared. The image quality of coronary artery was ranked by 3 levels, namely, level A, B and C. The data were statistically analyzed. Results The image quality triggered by 160 HU of group b was level A. The image quality triggered by 180 HU of group a was level A. Conclusion The optimum surestart is 180 HU when the heart rate 70 beats/per minute.

Under the influence of oncogenic signals and abnormal metabolism, the redox status of cancer cells often differs from that of the normal cells, manifesting as elevated generation of reactive oxygen species( ROS) and oxidative stress.Many signaling pathways involved in tumorigenesis can directly or indirectly regulate ROS metabolism.Currently, the biological significance of increased ROS in cancer cells is still somewhat controversial.ROS on the one hand can promote cancer development and drug resistance, and on the other hand can also cause cell injury and even cell death.To maintain cell viability and proliferation, cancer cells usually up-regulate their antioxidant capacity in adaptation to the intrinsic oxidative stress.Such adaptive mechanisms to oxidative stress are highly important in both cancer development and also play a major role in cancer cell response to therapy.Compelling evidences from recent studies have suggested that targeting the redox regulation mechanisms through proper intervention strategies may have significant therapeutic implications in cancer treatment.This article will focus on alterations of redox status in cancer cells, their adaptation to oxidative stress, and the underlying mechanisms.Potential therapeutic strategies based on such biochemical characteristics of cancer cells will also be discussed.

Objective To establish the model of traumatic brain injury in rats with controlled cortical impact (CCI), and investigate the features of coma and cognition. Methods 40 male Sprague-Dawley rats were randomly divided into control group (n=10), sham group (n= 10) and CCI group (n=20). CCI group was impacted at bilateral frontal lobe with the velocity of 3.5 m/s, depth of 7 mm and dwell time of 250 ms. The time of consciousness loss was recorded, and all the rats were investigated with Morris Water Maze 10 and 20 days after operation. Results The time of consciousness loss was longer in the CCI group than in the control group and the sham group (P<0.001). The escape latency was longer in the CCI group than in the control group and the sham group (P<0.001), while the percent of time spend in goal quarter during probe trial was less (P<0.001), both 10 days and 20 days after operation. Conclusion CCI at bilateral frontal lobe of rats can establish the model of severe traumatic brain injury with coma and long-term cognitive dysfunction.

Objective To evaluate the clinical efficacy of MRA in the arteries of the pelvis and lower extremity with automatic table movement (MobiTrak).Methods 12 cases suspected of pelvis and lower extremity artery diseases underwent dynamic 3D contrast enhanced MRA and automatic table movement at the same time.Three cases underwent artery angiography,four cases were detected by operation.Results All diseased arteries were well demonstrated.Among them,lower extremity artery occlusion 8,failing vascular grafts 2,artery aneurysms 2.Conclusion Automatic table movement is of value in assessing pelvis and lower extremity artery diseases accurately.And it is a reliable and potential new technique.

Objective To investigate the value of FIESTA sequence for the abdominal scanning of the patient undergoing uneffective respiratory triggering. Methods 40 cases undergoing uneffective respiratory triggering were adopted as the subjects. GE SIGNA 1.5T and fat-suppressed technique got involved in. Two chief physicians and two associate chief technologists compared the image quality and the lesion detective rate. Results FIESTA sequence was better than FSE T2WI in the aspect of image quality, but worse in lesion detective rate. Conclusion FIESTA sequence is clinically valuable for the abdominal scanning of patient undergoing unffective respiratory triggering.

Purpose To evaluate the diagnostic value of diffusion weighted imaging with high b value in acute cerebral microinfarcts.Materials and Methods Conventional MRI and diffusion weighted imaging with standard b value (b=1000 s/mm2) and high b value (b=3000 s/mm2) were performed in the 7 patients with acute cerebral infarction,and all the images were evaluated.The signal to noise ration (SNR) and contrast to noise ration (CNR) were measured.Results Five patients were detected much more microinfarcts in high b value as HB group than that in standard b value as SB group.The SNR and CNR were significantly higher in high b value group than that in standard b value group (P＜0.05),but the apparent diffusion coefficient value showed no significant difference between the two groups (P＞0.05).Conclusion DWI with high b value could sensitively detect acute cerebral microinfarcts with high clinical value.

Objective To understand the phenotype and enzyme genotype of pan‐drug resistant carbapenemase‐producing Acine‐tobacter baumannii to provide the evidence for clinical rational use of antibiotics and monitoring hospital infection .Methods A total of 117 clinically isolated strains of Acinetobacter baumannii were collected and performed the routine microbiological detection . Multi‐drug resistant Acinetobacter baumannii was screened by K‐B disk diffusion method .The phenotype of carbapenemase‐produ‐cing strains was detected by using the Carba NP colorimetry and modified Hodge test .The drug resistant genotype of multi‐drug re‐sistant Acinetobacter baumannii was verified by PCR .Results Among clinically isolated 117 strains of Acinetobacter baumannii ,64 strains were multi‐drug resistant Acinetobacter baumannii ,in which 33 strains were carbapenemase positive .OXA‐23 drug‐resistant genotype of carbapenemase was detected by PCR ,while IMP ,VIM and NDM‐1 drug resistant genes were not detected .Conclusion The CarbaNP method can rapidly detect carbapenemase‐producing strains with the advantages of strong sensitivity and simple oper‐ation ,which conduces to improve the detection rate of carbapenemase‐producing strains and monitor the nosocomial infection .

OBJECTIVETo evaluate early occult brain functional damage in patients with type 2 diabetes mellitus using resting-state functional magnetic resonance imaging (MRI).

METHODSHigh-resolution three-dimensional T1-weighted fast spoiled gradient recalled echo MRI and resting-state functional MRI images were obtained from 18 patients with type 2 diabetes mellitus and 18 normal control subjects. Regional homogeneity (ReHo) map, amplitude of low-frequency fluctuation (ALFF) map, and functional connectivity map of the bilateral hippocampus and posterior cingulate gyrus were calculated and voxel-based analysis was performed using two-sample t-test.

RESULTSIn type 2 diabetic patients, decreased ReHo was deteted in the right thalamus, hippocampus, olfactory cortex and left putamen as compared with the normal controls. The decreased ALFF was found mainly in the left middle frontal gyrus, right supramarginal gyrus and middle occipital gyrus in the diabetic patients. The patients showed reduced functional connectivity between the bilateral hippocampus but not between the bilateral posterior gyrus and the other brain regions.

CONCLUSIONThe occult brain damage is featured by decreased ReHo and ALFF in multiple brain regions and reduced functional connectivity between the bilateral hippocampus in type 2 diabetic patients.

Brain ; pathology ; Brain Injuries ; Brain Mapping ; Case-Control Studies ; Diabetes Mellitus, Type 2 ; pathology ; Frontal Lobe ; Gyrus Cinguli ; Hippocampus ; Humans ; Imaging, Three-Dimensional ; Magnetic Resonance Imaging

Objective To study the friction between brackets and archwires and the influential factors. Methods To test the friction of six combinations of canine bracket and stainless steel archwire, and to calculate the critical contact angles for each combination. Results The friction maintains stability with slight changes when the contact angle is smaller than the critical contact angle. The friction increases linearly when the contact angle is larger than the critical contact angle. The friction of different combinations of bracket-archwire are different and the critical contact angles are also different. Conclusion The critical contact angle influences the friction between bracket and archwire significantly. The critical contact angle is relevant to both the structure of the bracket and the size of the archwire.

Aim To investigate the mechanism of demethylation on adenosine (ADO )and homocysteine (HCY)-induced apoptosis in human hepatoma HepG2 cells .Methods HepG 2 cells were treated with differ-ent concentrations of ADO (1.0、2.0、4.0 mol · L-1 ) alone or in combination with HCY for 6h,12h and 24h,5-aza-2-deoxycytidine (5-Aza-CdR)as a positive control.Cell viabilities were assessed by CCK8 assay. Cell apoptosis was observed by AnnexinV-FITC/PI staining.The mitochondrial membrane potentials(ΔΨ) were measured by flow cytometry.The mRNA and pro-tein expressions of caspase-3,caspase-8,caspase-9, MDM-2,p53,Cytochrome C,DNMT1,DNMT3a,DN-MT3 b were detected by RT-qPCR and Western blot re-spectively.Results ADO alone or in combination with HCY significantly reduced the viability of HepG2 cells in a dose and time-dependent manner.The apoptotic rates of HepG2 cells after combination treatment with ADO and HCY at 1 .0,2.0,4.0 mol · L-1 for 24 h were (1 8.63 ± 1.25 )%,(29.42 ±2.37 )% and (42.47 ±3.09 )%,compared with the control group (1.30 ±0.82 )%,P <0.01;and the mitochondrial membrane potentials were decreased from 674.15 ± 82.8%(black control group)to (428.38 ±54.5)%, (297.78 ±30.5)%,(74.45 ±5.73)%,P<0.01, respectively.The expressions of caspase-3,caspase-8, caspase-9,MDM-2,p53,Cytochrome C were up-regula-ted and MDM-2 were down-regulated after combination treatment of ADO and HCY.The mRNA expressions of DNMT1 ,DNMT3 a and DNMT3 b were down-regulated after combination treatment with ADO and HCY or 5-Aza-CdR alone.Conclusion Combination treatment of ADO and HCY can cause cellular methylation chan-ges.The effects of demethylation of ADO and HCY may activate p53 gene and mitochondrial pathway, which at last leads to HepG2 cell apoptosis.