Objective The enhanced patterns of atherosclerotic plaque on dynamic contrastenhanced MRI have not been well studied. The aim of this study was to explore the patterns of plaque enhancement and their underlying mechanism by using dynamic contrast-enhanced MRI (DCE-MRI).Methods Atherosclerotic plaques were induced in the aorta of 12 New Zealand White rabbits by a combination of endothelial denudation and high-cholesterol diet. Ten to sixteen weeks after surgery, DCEMRI was performed with a fast spin echo T1 weighted sequence. Thirty-five phases of images were obtained at 71-second intervals. Gd-DTPA was injected coincident with the third scan via marginal ear vein. Specimens were harvested within 12 hours after imaging for HE staining and CD31 immunohistochemical staining which was used to highlight nco-vessels. Plaque enhancement patterns were studied and compared with histological findings. Signal intensity of each plaque section was normalized to pre-contrast signal intensity of psoas muscle, after which signal intensity versus time curve was drawn. Pearson correlation coefficient was used to reveal association between histological neo-vessel count and descriptive parameters derived from signal intensity versus time curve. Results Plaques were significantly enhanced by Gd-DTPA. Enhancement patterns could be described as fast-in and slow-out. Differences in patterns of enhancement were observed between tissues, with fibrous tissue enhanced more than lipid aggregation and leukocyte foci. Peak enhancement( 1. 05 ±0. 30) , initial slope(0. 82 ± 0. 28 ) and area under the curve at early phase(4.97 ± 1.67) derived from signal intensity-time curve had significant correlations with neo-vessel count( 117.7 ± 93. 3) ( r= 0. 553,0. 468, 0. 554 respectively, P ＜ 0. 05 ) . Conclusions The enhanced patterns of atherosclerotic plaque by Gd-DTPA were fast- in and slow-out. Neovascularization, increased endothelial permeability and extracellular matrix may be the reasons for plaque enhancement by Gd-DTPA. DCE-MRI has the potential to quantify the extent of neo-vasculature formation within plaques.

Objective To evaluate the reliability of a rat model of acute cerebral ischemia and reperfusion by using cerebral perfusion functional CT.Methods A stable and reversible focal ischemia model with unilateral middle cerebral artery occlusion was established and evaluated by CT perfusion imaging and TTC staining.Results Artificial Occlusion of the MCA resulted in ipsilateral cerebral infarcts in all study animals.Hypoperfusion was definitely recorded in all CT perfusion images obtained after MCA occlusion and was significantly correlated with the final lesion size.Blood flow was restored after pulling the thread out of the artery.Conclusions The method of establishing an acute focal cerebral ischemia and reperfusion model by thread insertion in our study is simple and stable.If we can screen the stroke model with CT perfusion examination,the error caused by variance of model can be reduced.Thereby it provides a platform for researchers to investigate acute cerebral ischemia and recirculation.

Objective To investigate the relationship between apparent diffusion coefficient (ADC)value of rectal adenocarcinoma on DWI and its pathological grading.Methods The ADC values of 46 rectal adenocarcinomas were measured and compared with their histopathological grades.Results The 46 rectal adenocarcinomas included well differentiated adenocarcinomas in 14,moderate-ly differentiated ones in 20,and poorly differentiated ones in 12.The ADC values of well,moderately and poorly differentiated ade-nocarcinomas were (1.125±0.103)×10 -3 mm2/s,(1.030±0.098)×10 -3 mm2/s and (0.922±0.091)×10 -3 mm2/s,respective-ly,exhibiting a statistical difference (χ2 =1 7.35 1,P =0.000).Mann-Whitney U test showed that difference in ADC value between different histopathological grades was statistically significant.Conclusion ADC value of rectal adenocarcinoma can be used as a bio-marker for cell grading to guide treatment decision and prognosis assessment.

Objective To estimate the value of fecal tumor M2-PK in the detection of colorectal adenoma and to evaluate its potential as a screening tool for colorectal adenoma.Methods Enzyme-linked immunosorbent assay (ELISA) was used to detect the fecal tumor M2-PK in stool samples of 65 patients with colorectal adenoma and 25 controls.At the same time,the peripheral blood tumor markers such as carcinoembryonic antigen (CEA),carbohydrate antigen (CA) 19-9,CA24-2 and fecal occult blood test (FOBT) were detected in the colorectal adenoma group.Results The detection value of fecal tumor M2-PK in the colorectal adenoma group showed a significant increase,compared with the control group((6.033±4.123) U/ml vs.(2.782±1.464) U/ml,t=-3.839,P=0.000).The highest detection value was found in the group where the diameter of adenoma was greater than or equal to 2 cm ((8.775±6.548) U/ml,t=9.635,P=0.034).The larger the diameter of adenoma,the higher the positive rate of fecal tumor M2-PK (85.7% vs.41.7% vs.29.6%,χ2=11.977,P=0.003).In the colorectal adenoma group,The positive detection rate of fecal tumor M2-PK was significantly higher than that of CEA,CA19-9,CA24-2 and FOBT (46.2% vs.6.2% vs.1.5% vs.1.5% vs.27.7%,?2=76.607,P=0.000).Conclusion Fecal tumor M2 pyruvate kinase has a good clinical value in the diagnosis of colorectal adenoma.

Objective To investigate ATM deletion [del (ATM)] in chronic lymphocytic leukemia (CLL) and study its correlation with the clinical stage. Methods Spectrum Orange~(TM) labeled sequence specific DNA probe for ATM locus on 11q22.3 and fluorescence in Situ hybridization (FISH) was used to examine del (ATM) in 28 newly diagnose patients with CLL. FISH analysis were performed on bone marrow smears. Clinical staging was done according to Binet Method.Fisher exact propability was used to study the relations between del (ATM) and clinical feature. Results 4 out of the 28 cases were found with deletion of ATM. The incidence of del (ATM) in BinetA, BinetB and BinetC was 1/9 (11.1 %), 1/8 (12.5 %), 2/11 (18.2 %), respectively. Fisher exact propability showed that deletion of ATM was not associated with its clinical feature. Conclusion Application of FISH on archival bone marrow smears is a simple, liable method, and can be readly used to retrospective study of clonal blood system diseases. Deletion of ATM was common cytogenetic changes in CLL patients.And the significance of del (ATM) in the prognosis of CLL in China needs to be further investigated.

Objective To investigate the prevalence and cardiovascular risk factors of silent brain infarct (SBI) in Shunyi Cohort.Methods This study was based on the population based Shunyi Study in China.One thousand and twenty-seven stroke-free participants older than 35 years,who completed cerebral MRI,were included.Cardiovascular risk factors were assessed by interview,physical examination and blood sample tests.SBI was evaluated on 3D-T1WI,T2WI and FLAIR sequences.Associations between risk factors and SBI were analyzed by Logistic regression and adjusted for age,sex,and relevant confounders.Results One thousand and twenty-seven participants,aged (55.9 ± 9.4) years,37.7％ male,were assessed.One hundred sixty-four participants(16.0％) had SBI on MRI.The prevalence of SBI increased by age (every 10 years,OR=2.12,95％ CI 1.74-2.58,P＜0.01).Hypertension(OR =2.67,95％ CI 1.77-4.04,P＜0.01),diabetes(OR=2.48,95％ CI 1.64-3.76,P＜0.01) and smoking(OR=1.98,95％ CI 1.08-3.62,P =0.028) were significantly associated with SBI.Conclusions The prevalence of SBI in this Chinese population is 16.0％,which increases with age.Hypertension,diabetes and smoking are associated with SBI.

OBJECTIVETo discuss the key role of various mode of circulation assist in the radical operation of retro-peritoneal malignancy with the inferior vena cava thrombotic involvement.

METHODS>From the June 1999 to the March 2001, 6 patients with retro-peritoneal malignancy with thrombosis involving the inferior vena cava, were completely resected with various mode of circulation assist.

RESULTSAll the patients operated have good outcomes and follow-up (1 - 20 months) except one death 1 month after operation.

CONCLUSIONAccording to the various types of tumor thrombi, individualized and technically feasible circulation assist mode should be utilized to achieve the satisfactory outcomes.

Aged ; Assisted Circulation ; Humans ; Male ; Middle Aged ; Retroperitoneal Neoplasms ; blood supply ; surgery ; Surgical Procedures, Operative ; Vena Cava, Inferior ; surgery

Blood pressure management is an important and complex part of the treatment of acute ischemic stroke. There is no consensus on blood pressure management options for patients with acute ischemic stroke receiving intravenous thrombolysis. Blood pressure levels and blood pressure variability before and after thrombolysis, and timing of blood pressure interventions have significant effects on hemorrhagic transformation, functional outcome, and recurrence risk in patients with acute ischemic stroke. This article reviews the necessity, safety, goals of blood pressure management before and after thrombolysis, and its impact on the outcomes in acute ischemic stroke.

Rhythm of blood pressure refers to the circadian variation of blood pressure, which is regulated by clock genes. However, the rhythm disorder of blood pressure increases the risk of stroke. Taking the process of blood pressure regulation as a clue and focusing on the clock gene pathway, this article explores the possible mechanism of period gene regulating renin-angiotensin-aldosterone system in rhythm of blood pressure, so as to provide reference for the in-depth study of the relevant mechanism of rhythm disorder of blood pressure and search for a new target for the primary prevention of cerebrovascular diseases.

Intensive glucose control increases the all-cause mortality in type 2 diabetes mellitus (T2DM); however, the underlying mechanisms remain unclear. We hypothesized that strict diet control to achieve euglycemia in diabetes damages major organs, increasing the mortality risk. To evaluate effects on major organs when euglycemia is obtained by diet control, we generated a model of end-stage T2DM in 13-week-old Sprague-Dawley rats by subtotal pancreatectomy, followed by ad libitum feeding for 5 weeks. We divided these rats into two groups and for the subsequent 6 weeks provided ad libitum feeding to half (AL, n=12) and a calorie-controlled diet to the other half (R, n=12). To avoid hypoglycemia, the degree of calorie restriction in the R group was isocaloric (g per kg body weight per day) compared with a sham-operated control group (C, n=12). During the 6-week diet control period, AL rats ate three times more than rats in the C or R groups, developing hyperglycemia with renal hyperplasia. R group achieved euglycemia but lost overall body weight significantly compared with the C or AL group (49 or 22%, respectively), heart weight (39 or 23%, respectively) and liver weight (50 or 46%, respectively). Autophagy levels in the heart and liver were the highest in the R group (P<0.01), which also had the lowest pAkt/Akt levels among the groups (P<0.05 in the heart; P<0.01 in the liver). In conclusion, glycemic control achieved by diet control can prevent hyperglycemia-induced renal hyperplasia in diabetes but may be deleterious even at isocaloric rate when insulin is deficient because of significant loss of heart and liver mass via increased autophagy.
Albuminuria/urine ; Animals ; *Autophagy ; Cholesterol, HDL/blood ; Diabetes Mellitus, Experimental/blood/*diet therapy/*pathology/urine ; Diet/*adverse effects ; Eating ; Glycosuria/urine ; Insulin/blood ; Liver/*pathology ; Male ; Myocardium/*pathology ; Organ Size ; Proto-Oncogene Proteins c-akt/metabolism ; Rats, Sprague-Dawley ; Serum Albumin/analysis