Objective To observe the appearances of decussation of superior cerebellar peduncle (SCP) on MR diffusion tensor imaging (DTI) with different parameters of scanning and reconstruction. Methods Twenty healthy volunteers were examined on Siemens 3.0T MR DTI (b=0, 1000 s/mm~2), post processing were made in Siemens Leonardo workstation using Siemens Standar 6 dirs software to reconstruct the white matter fibers with different fractional anisotropy (FA) threshold value (0.04-0.20), angle threshold value (20°-89°) and voxel size (1.2 mm×1.2 mm×3.0 mm-1.6 mm×1.6 mm×5.0 mm). Results Crossing fiber was presented each voxel group on diffusion tensor tractography (DTT). The types of crossing fiber in the small voxel were more than those of big voxel image obviously. Reduced along with the FA threshold value, the number of crossing fiber increased gradually. After the peak value (FA=0.08), the number of crossing fiber reduced along with the FA threshold value reduced gradually. Increased along with the angle threshold value, the number of crossing fiber increased gradually. The number of crossing fiber reduced along with the angle threshold value increased gradually after the peak value (the angle threshold value＝80°). There were 5 kinds of MR fiber tracking appearances at the level of decussation of SCP on DTT. The fiber crossed to the opposited red nucleus in anterior-posterior style, superior-inferior style and single main bundle fiber. Kissing fiber and missing fiber sign was shouw in all subjects, which mainly located in the center of the decussation. Conclusion DTT FACT can show the descussation of SCP in most health subjects with five typical appearance. The descussation of SCP has the obvious appearances, may be causing by individual difference. For the crossing fiber of SCP, voxel size 1.2 mm×1.2 mm×3.0 mm, FA 0.08 and the angle 80° are recommended.

BACKGROUND: Navigation systems all can improve the accuracy rate in cervical pedicle screw insertion, but cannot achieve desired outcomes because of some shortcomings, such as poor imaging quality, complicated operation, poor real-time performance, and invasive navigation.OBJECTIVE: To study the accuracy of X-ray fluoroscopy and CT three-dimensional image navigation in cervical pedicle screw insertion.METHODS: Totally 90 patients undergoing cervical pedicle screw insertion from the First Affiliated Hospital of Nanyang Medical College were enrolled, and randomly divided into control and experimental groups (n=45 per group). 132 cervical pedicle screws were inserted into the patients in the control group manually under X-ray fluoroscopy, and 128 ones were inserted into the patients in the experimental group assisted with CT three-dimensional image navigation. The operation time and intraoperative blood loss in the two groups were recorded. Postoperative CT three-dimensional reconstruction was performed to compare the placement accuracy between two groups.RESULTS AND CONCLUSION: The excellent and good rate of placement in the experimental group (95.3%) was significantly higher than that in the control group (88.6%, P < 0.05). (2) The operation time and intraoperative blood loss in the experimental group were significantly higher than those in the control group, and the navigation matching time and radiant quantity in the experimental group were significantly less than those in the control group (P < 0.05). (3) The Japanese Orthopedic Association scores showed no significant difference between two groups before surgery (P > 0.05),and were significantly improved in the experimental group compared with the control group at 3 and 6 months postoperatively (P < 0.05). The incidence of complications in the experimental group was significantly lower than that in the control group (7% versus 16%, P < 0.05). (5) These results suggest that compared with X-ray fluoroscopy, CT three-dimensional image navigation can improve the accuracy of cervical pedicle screw insertion, showing higher safety and precision. However, it needs complicated operation skills, and long operation time results in massive intraoperative blood loss; thereafter, choosing which placement method depends on the patient condition.

Objective To evaluate the interventional of bare-handed core muscle strength training and the sling exercise therapy (SET) on low back pain.Methods The soldiers of an Air Force Station who suffered from low back pain participated in the study.One hundred and forty-four patients were equally divided into three groups: the core muscle strength group (using core muscle strength training and the general physical therapy), the SET group (using SET and general physical therapy), and the control group (using the general physical therapy).All the groups were tested for 6 weeks.Questionnaires were distributed to the three groups before intervention, two weeks, four weeks and six weeks after intervention in order to find out about the degree of LBP, lumbar function and activity of these cases.Changes in the lumbar muscle strength were observed.Results The number of the patients who completed the test included 43 cases in the bare-handed core muscle strength group, 43 cases in the SET group and 44 cases in the control group, respectively, the VAS scores were 3.25, the Roland scores were 5.83,the FFD scores were 8.58 of the bare-handed core muscle strength group;the VAS scores were 3.30, the Roland scores were 5.93,the FFD scores were 8.10 of the SET group;the VAS scores were 2.41, the Roland scores were 3.03,the FFD scores were 7.40 of the control group.The LBP intervention efficiency of the three groups was 90.90%, 85.13% and 46.82%, respectively.There was no significant difference in indexes between the test groups(P>0.05).But compared with the control group,there was significant difference(P<0.05).Conclusion The bare-handed core muscle strength training and SET have obvious effects on LBP cases.According to their own infrastructure and facilities, military health care organizations in different environments can intervene in LBP cases with the bare-handed core muscle strength training or SET to alleviate the pain effectively.

Purpose With the progression of brain tissue aging, the transport and drainage characteristics of metabolites and secretory products for neurons in extracellular space occurs irreversible change. This paper aims to investigate and quantify MR tracer diffusion characteristics in cerebral interstitial fluid of elderly SD rats. Materials and Methods MR contrast agent Gd-DTPA was injected into the caudate nucleus of two groups of rats including 8 in experimental group (15-17 month old) and 15 in control group (7-10 month old). MR scan was performed at 0.25 h, 0.5 h, 1 h, 2 h, 3 h and 4 h to observe the dynamic distribution in the caudate and measure the diffusion and clearance rate. Results There was no statistically significant difference in diffusion rate and D* between control group with (3.32±0.70)×10-4 mm2/s and experimental group with (3.25±0.46)×10-4 mm2/s (t=1.739, P>0.05). The clearance rate k' was significantly different between control group (0.62±0.12)×10-4/s and experimental group (0.29±0.08)×10-4/s (t=11.602, P<0.05). Conclusion The degeneration of aging brain tissue changes the composition of extracellular space resulting in decreased speed of ISF clearance. This may cause accumulation of metabolites which eventually triggers a variety of age-related diseases.

Objective: To establish the cardio-renal syndrome (CRS) model by coarctation of abdominal aorta (CAA) with renal ischemia reperfusion injury (RIRI), and to observe the mRNA expression of pro-renin receptor [(P)RR] in experimental rats. Methods: A total of 42 Wistar rats were randomly divided into 4 groups: Sham group, CAA group, RIRI group and CAA+RIRI group.n=10 in each group, 2 rats died during the modeling and all animals were treated for 16 weeks. Blood levels of BNP, creatinine (Cr), urea nitrogen (BUN), the activity of rennin, the contents of angiotensin-I (AT-I), AT-II and aldosterone were examined by laboratory test. The diastolic end inter-ventricular septum thickness (DEIVST), DELVPT, LVEF, ventricular weight index (VWI) and cardiac weight index were detected by small animal echocardiography. The histological changes of myocardium and kidney tissue were measured by HE staining, and the mRNA expressions of pro-renin receptor in myocardium and kidney tissues were measured by RT-PCR. Results: Compared with Sham group, blood levels of BNP were increased in the other 3 groups,P<0.05; compared with CAA group, CAA+RIRI group had increased levels of Cr and BUN,P<0.01; compared with Sham group and RIRI group, CAA+RIRI group showed increased blood level of aldosterone,P<0.05. Compared with CAA group, CAA+RIRI group presented increased rennin activity,P<0.05. Blood levels of AT-I and AT-II were not signiifcantly increased among 3 operation groups,P>0.05. Compared with CAA group, CAA+RIRI group had more obvious changes of DEIVST and LVEF,P<0.01. Compared with RIRI group, CAA+RIRI group had more obvious ventricular hypertrophy, higher VWI and cardiac weight index, allP<0.05. HE staining presented that CAA+RIRI group had broadening of myocardial cell bundle space, decreased left renal index, severe tubular atrophy and partial glomerular atrophy. RT-PCR demonstrated that compared with Sham group, the mRNA expressions of pro-renin receptor in myocardium and kidney tissues were decreased in the other 3 groups. Conclusion: Combined CAA+RIRI method may damage the cardial and renal tissues at the same time which was more severe than either CAA or RIRI. While CAA+RIRI model has better controllability and higher consistency that provides a methodological reference for pro-renin receptor in treating CRS in experimental rat’s model.

Objective In order to investigate the relationship between erythrocyte immune function and seleni- um(Se) level. Method Red blood cell immune adherence(RCIA) function,serum RCIA regulatory factor, blood Se content and activities of glutathione peroxidase(GPX) of residents in Keshan disease(KD) endemic and non-endemic areas were comparatively studied. Forty-eight residents in KD endemic area aged 13～ 16 years were divided into 2 groups. The residents in the experimental group were orally given 200μg Se daily as Se yeast for 12 weeks, and their erythrocyte Se content and activity of glutathione peroxidase (GPX),RCIA function,serum RCIA regulatory function and circulating immune complexes(CIC) content were determined. ResultsThe results showed that the rosette for- mation rates of erythrocyte and blood Se levels of the residents in KD area were significantly lower and the rosette formation inhibitory rate of serum RCIA of the residents in KD area was significantly higher than those in the non-endemic area. Erythrocyte Se contents, GPX activities and rosette formation rates of erythrocyte were sig- nificantly increased and the rosette formation inhibitory rates of serum RICA were significantly decreased after sup- plementing Se,but the difference in the contents of serum CIC was not significant. ConclusionThe increase of ery- throcyte immune function by Se-supplement might be one of the effective mechanisms in the prevention of KD by Se- supplement.

Objective To explore the feasibility of establishing a swine model of liver cirrhosis with portal hypertension by portal infusion of 80％ alcohol.Methods A total of 13 Guizhou miniature pigs were randomly divided into three groups,experiment group 1 (n=5),experiment group 2 (n=5) and control group (n=3).Experiment groups of pigs received portal infusion of 80％ alcohol in volumes of 5 ml in group 1,and 10 ml in group 2,and the pigs in control group received portal perfusion of saline in volumes of 10 ml.All animals were performed direct portal angiography,the portal vein pressures and diameter were also detected before,immediately and 6 weeks after the infusion.All animals underwent liver biopsies before and 6 hours,1-6 weeks after operation.And contrast-enhanced abdominal CT was performed before and 6 weeks after operation.All animals were dissected 6 weeks after operation,aud each leaf of liver specimens were performed histological examination.Results There was no statistically significant difference of the portal venous pressure and diameter before infusion and 6 weeks after infusion in the experiment group 1 and control group (all P＞0.05).In the experiment group 2,compared with pre infusion,the portal vein pressure and diameter were higher than those of immediately and 6 weeks after infusion (all P＜0.05).In both experiment group 1 and group 2,all pigs had developed into liver fibrosis,the METAVIR score of 2 pigs in group 1 and 5 pigs in group 2 respectively were up to grade 4.Conclusion Portal infusion of 80％ alcohol is more suitable for establishing a swine model of liver cirrhosis with portal hypertension.

Objective To evaluate the feasibility and diagnostic accuracy of CE-MRA with low dose contrast agent by comparison with DSA in diabetic patients with peripheral arterial diseases. Methods ( 1 )Study in vitro: test tubes containing Gd-DTPA of different concentrations were scanned, and the relationship between signal intensities and concentrations of GD-DTPA was analyzed. DSA and CE-MRA with selected concentrations of Gd-DTPA were performed on stenotic vascular models to estimate the proper low dose of GD-DTPA for clinical applications. (2) Clinical applications: 78 diabetic patients with peripheral arterial diseases were scanned from the abdomen and pelvis station to the calf-foot station in a 3 T MR system with standard bolus chase 3D CE-MRA sequence after injection of 13 ml GD-DTPA . The image quality,diagnostic rate of stenosis of arteries in calf and degree of venous contamination were evaluated with Fisher's exact test. DSA images of 220 vascular segments in 22 patients ( 10 segments per patient) were acquired as the gold standard and compared with CE-MRA by using Kappa test. Results The MR signal intensities were proportional to the concentrations of contrast agent in present study, and all stenotic segments of vascular model were displayed by CE-MRA with GD-DTPA at lower concentration of 1.5 mmol/L. As for MRA images of 78 diabetic patients with low dose Gd-DTPA, about 97.4% (76/78) showed diagnostic image quality for pelvic and thigh stations. But the MRA images of lower extremities were interfered by the venous contamination significantly (P ＜ 0.01 ). Compared with DSA for 22 patients, the diagnostic sensitivity, specificity and agreement coefficient (Kappa value) of MRA were 96. 0% ( 168/175), 73.3%(33/45), and 0.72 (P＜0.01), respectively. Conclusion Using 3.0 T MR scanner, high quality CE-MRA of lower limb arteries can be obtained for clinical applications with contrast agent dose as low as 13 ml,which has comparable diagnostic sensitivity and specificity with DSA. But the limitation of venous contamination in MRA image should be resolved in further studies.

Objective:To study clinical and genetic factors for early phase gastric mucosal injury due to long-term aspirin use in elderly people treated with angiotensin-converting enzyme inhibitors(AVCEI)/angiotensin II AT-1 receptor blockers(ARB)or statins.Methods:Four hundred and sixty-seven elderly persons taking 100 mg aspirin per day for a long time combined with ACEI/ARB or statins in our hospital were enrolled and retrospectively analyzed.According to endoscopy results, patients were divided into the normal gastric mucosa group(n=125), chronic gastritis group(n=199)and gastric mucosal erosion group(n=143). Clinical features and SLCO1B1 genetic polymorphisms affecting the absorption of ACEI/ARB and statins were statistically analyzed.Results:Compared with the normal gastric mucosa group, reduced glomerular filtration rate(GFR)was a risk factor for chronic gastritis and gastric mucosal erosion[(66.5±24.4) ml·min·1.73 m -2vs.(70.9±18.5) ml·min·1.73 m -2, OR=5.06, 95% CI: 2.14-11.51, P<0.01]. Advanced age[(78.5±10.1) years old vs.(71.5±9.6) years old, OR=1.33, 95% CI: 1.04-2.87, P<0.05], history of peptic ulcer[14.0% or 20/143 vs.5.6% or 7/125, OR=2.41, 95% CI: 1.08-5.01, P<0.05], no prescription of proton pump inhibitor[18.2% or 26/143 vs.50.4% or 63/125, OR=0.18, 95% CI: 0.11-0.31, P<0.01], lower GFR[(55.8±23.1) ml·min·1.73 m -2vs.(70.9±18.5) ml·min·1.73 m -2, OR=8.04, 95% CI: 3.02-22.6, P<0.01]and SLCO1B1*1b diplotype[42.0% or 60/143 vs.24.0% or 30/125, OR=2.64, 95% CI: 1.59-4.17, P<0.05]were risk factors for gastric mucosal erosion. Conclusions:The SLCO1B1*1b diplotype may increase the risk of gastric mucosal erosion induced by aspirin via weakening the protective effects of ACEI/ARB and statins on the gastric mucosa.Advanced age, a history of peptic ulcer, no prescription of proton pump inhibitors and renal function decline are risk factors for gastric mucosal injury.

Objective To investigate the characteristics of mycobacteria species distribution in human immunodeficiency virus (HIV)-positive patients co-infected with mycobacteria in Guangzhou. Methods A total of 133 mycobacteria strains isolated from HIV-positive patients and 150 strains isolated from HIV-negative patients were included in this study. After DNA extraction of mycobacteria, mycobacteria species identification was performed by sequencing of multiple genes.Differences in the identified species were compared between patients with and without HIV infection and the correlation between CD4 + T cells level and the mycobacterial species distribution was analyzed.Chi-square test was used for statistical analysis.Results Of the 133 mycobacteria strains isolated from HIV-positive patients, 82 were identified as Mycobacterium tuberculosis complex (MTC ). Fifty-one were identified as nontuberculous mycobacteria (NTM),of which the main species was Mycobacterium avium complex (MAC,31/51).Of the 150 mycobacteria strains isolated from HIV-negative patients,126 were identified as MTC and 24 as NTM,of which the main species was Mycobacterium abscessus (9/24).In patients with CD4 + T cell counts ≤100/μL,the positive rate of mycobacteria was 75 .94%(101/133),93.55 %(29/31) of MAC and 85 .00%(17/20)of other NTM.When the CD4 + T cell counts >100/μL,the positive rate for mycobacteria were all obviously decreased.Conclusions The proportion of NTM infection is higher in HIV-positive patients than HIV-negative patients in Guangzhou. Among HIV-positive patients > the most prevalent NTM species is MAC, while Mycobacterium abscessus is the most common species in HIVnegative patients. Mycobacterial infection in acquired immunodeficiency syndrome patients is closely associated with low CD4+ cells level.