Objective To analyze the accuracy,sensitivity and safety of multidetector CT angiography(MDCTA) and DSA;furthermore to explore the clinical value of MDCTA in studying the delayed cerebral vasospasm(DCVS) .Methods Delayed cerebral vasospasm was induced in 17 rabbits by injection of autologuous blood into the cisterna magna and followed by a second injection 24 hours later.MDCTA and DSA were carried out at the 7th day before and after the procedure in order to obtain the data of vascular diameter changes for comparative study.Results The basilar artery diameters detected by MDCTA were shown preoperatively as(1.55 ? 0.14) mm and postoperatively as(0.95 ? 0.20) mm;and detected by DSA as(1.61 ? 0.19) mm and(1.00 ? 0.17) mm postoperatively;showing statistically equivalence between the two methods.Conclusions MDCTA is recommended as a reliable,rapid,and minimally invasive diagnostic method,providing a new technique for the delayed cerebral vasospasm research.

Objective To explore the MRI T 1WI features of the hyperacute intracerebral hematoma by super-low-field MR.Methods 160 patients with hyperacute intracerebral hematoma were examined by using MR unit of 0.04T magnetic(WDLMW-400) and PS3D T 1WI(TR=125 ms,TE=25 ms).Results Hematomas located in basal ganglia(140 cases),cerebral lobe(13 cases),cerebellum(5 cases) and brain stem ( 2 cases) respectively.All of the hyperacute hematomas showed short T 1 signal intensity in PS3D T 1WI;the mass effects and perihematoma edema also can be found in all of the 160 cases.Conclusion This study shows that the super-low-field MRI is superior to medium and high field MRI in diagnosis of hyperacute intracerebral hematoma.

Aerobic and muscle-strengthening exercise is essential for weight management, in addition to diet control. Engaging in moderate-intensity aerobic exercise for 150 to 300 minutes a week and in muscle-strengthening exercise more than twice a week is recommended to reduce obesity. High-intensity aerobic exercise is also effective and can save time. Extra caution is needed to prevent injuries during high intensity exercise. Diabetic patients should prevent hypoglycemia and monitor the status of their feet. Exercise modification is needed in patients with complications of diabetes. Individuals with hypertension can do muscle-strengthening exercises safely. Lower-impact exercises are recommended for patients with osteoarthritis and extremely obese patients.
Diabetes Mellitus ; Diet ; Exercise ; Foot ; Humans ; Hypertension ; Hypoglycemia ; Obesity ; Osteoarthritis

Objective To explore the chiaical value of cerebral perfusion reduction after subarachnoid hemorrhage(SAH)by multi spiral CT perfusion in rabbits.Methods 32 male Japanese big-ear rabbits of clean level were randomly divided into 2 groups:Group A(n =8),the normal group,were to obtain normal MS-CTP values of rabbit cerebrums;Group B(n =24),the SAH group was made into two-hemorrhage animal models,checked on seven day by multi spiral CT perfusion.The source data was transmitted to the post-processing workstation ADW 4.2.Perfusion parameters maps(CBF)of both sides of frontal,parietal and basal ganglia were got by computing.Each rabbit was killed immediately after scanning,and the spider blood was observed.Results The average CBF value of the two groups:The difference was not statistically significant at the frontal(t =1.740,P =0.092)and parietal(t =1.868,P =0.072); The average values of CBF were significantly decreased at the basal ganglia(t =2.481,P =0.019).Group B showed the distribution of blood clot in the basal cistern,but there was no blood clot at the frontal and parietal.Conclusion The monitor perfusion changes of rabbit brain after SAH could be detected by MS-CTP,and the lower of regional cerebral perfusion had a relationship with the distribution with the blood clot,and it could instruct the early diagnosis of cerebral perfusion,and the clinical benefit to early intervention treatment.

Objective To study the effects of two different methods of high-pressure injections on imaging quality of synchronous left axillary artery and vein by using volume CT.Methods Forty seven patients who underwent left axillary vein and artery CTA examination study were analyzed retrospectively according to the contrast agent injection scheme and was divided into two groups A and B.Group A of 25 patients used protocol A,adopted clinical routine delay scanning method,via right elbow vein inject contrast medium.Group B of 22 patients used protocol B,adopted artery delayed imaging combined with vein direct imaging method,via right elbow vein,left radial vein inject contrast agent,respectively.Both values of CT and contrast to noise ratio (CNR) of two groups were compared,objective image quality was compared by two blinded readers.Mann Whiteny U test was used.Results The median of CT values for left axillary artery in group A was 151.9 HU.The median of CNR values for left axillary artery in group A was 7.4.The median of CT values for left axillary vein in group A was 116.0 HU.The median of CNR values for left axillary vein in group A was 3.83.The median of CT values for left axillary artery in group B was 348.8 HU.The median of CNR values for left axillary artery in group B was 25.3.The median of CT values for left axillary vein in group B was 497.0 HU.The median of CNR values for left axillary vein in group B was 35.4.Both values of CT and CNR in two groups showed significant difference (Z=-5.735,-5.799,-5.863 and-5.863,P＜0.01).All of the median scores in group B were greater than in group A(P＜0.01).Conclusion The enhancement effect of protocol B in the left axillary arteriovenous synchronous imaging is significantly higher than those of protocol A,and demonstrates clear image quality and clearer anatomic relationship.

Objective To evaluate perfusion computed tomography in the assessment of portal vein pressure changes in an experimental dog model of liver cirrhosis and portal hypertension.Methods The canine model of cirrhosis and portal hypertension was induced by portal vein stenosis with combination of systemic thioacetamide(TAA) feeding in drinking water.All of the Beagles in control group and cirrhotic group underwent hepatic perfusion on a spiral CT scanner.The parameters of hepatic perfusion were calculated by the method of deconvolution.The portal vein pressure was measured by a laparotomy surgery.Results ① In control group, the portal vein pressure was ( 14.5 ± 2.2) cm H2O, while it was (23.1 ± 2.8) cm H2O in PHT group, there was significant difference in the portal vein pressure between the two groups (P＜0.05).② The blood flow(BF) was (112 ±14) ml·100 g-1·min-1 in controls, while ( 96 ± 11) ml·100 g-1·min-1 in PHT group; the blood volume ( BV ) in control group and PHT group was (10 ±3) ml·100 g-1 and (11 ± 5) ml· 100 g-1, respectively; the mean transit time( MTT) was (7.1 ± 2.0) s and (10.4 ± 3.5) s, respectively; the hepatic arterial fraction (HAF) was ( 24 ± 5) % and ( 37 ± 6)% , respectively; the hepatic arterial perfusion (HAP) was(27 ±6) ml·100 g-1·min-1 and (35 ±5) ml·100 g-1·min-1, respectively; the portal venous perfusion (PVP) was (85 ± 13) ml·100 g-1·min-1 and (61 ±11) ml·100 g-1·min-1, respectively.There was significant difference in all parameters between the two groups except the parameter BV(P ＜ 0.05).③ In PHT group, the PVP and BF were negatively correlated with the portal vein pressure, while positively correlated with MTT and HAF.Portal vein pressure was negatively correlated with PVP, the equation, Y = 36.624 -0.219X, was deduced with linear regression analysis, by which the portal vein pressure in PHT Beagles was ( 23.2 ± 2.4) cm H2O, which was correlated with the observed by laparotomy value (23.1 ± 2.8) cm H2O (r = 0.843, P ＜ 0.05).Conclusion CT perfusion is a new non-invasive and effective method for assessment of portal vein pressure.

Objective To evaluate 1-week and 1-year outcomes of carotid artery stenting (CAS)using cerebral perfusion CT(PCT). Methods The clinical database of 20 patients with unilateral carotid artery stenosis( ≥60% ) who underwent CAS were retrospectively reviewed. Relative cerebral blood volume (rCBV), relative cerebral blood flow(rCBF) and relative mean transit time( rMTT) were measured by using cerebral PCT within one week before CAS and at one week and at one year after CAS. Cerebral MRI was performed within one week before CAS. The noncontrast CT was performed within one week before CAS and immediately after CAS. The arteriography was performed at one year after CAS. The variance analysis was performed to determine whether there were significant differences of rCBV, rCBF, rMTT in anterior cerebral artery area( ACA area), middle cerebral artery area( MCA area), posterior cerebral artery area( PCA area),basal ganglia area, front and back cortical watershed area( CWS area) and internal watershed area( IWS area) among the different time points. Results In the three measures, there was no significant difference of rCBV in all areas among the three time points( P ＞ 0. 05 ) , and there was no significant difference of rCBF and rMTT in PCA area( P ＞ 0. 05 ), but there were significant differences of rCBF and rMTT in all other areas among the three time ponits(P ＜0. 01). In one week before CAS, at one week and at one year after CAS, rCBF of 20 patients is 0. 86 ±0. 06, 0. 95 ±0. 04, 0. 98 ±0. 07 in ACA area, 0. 81 ±0. 04, 1.06 ±0. 04, 1.03 ±0.07 in MCA area, 0. 84 ±0. 06, 0. 97 ±0. 04, 0. 96 ±0. 04 in basal ganglia, 0. 78 ±0. 03,0. 97 ±0. 03, 0. 96 ±0. 02 in front CWS area, 0. 77 ±0. 03, 1.00 ±0. 02, 0. 98 ±0. 03 in back CWS area,and 0. 80 ± 0. 04, 0. 94 ± 0. 03, 0. 93 ± 0. 04 in IWS area ( F = 18. 95, 146. 41,63.03,540. 85,415.97,164.19, P＜0. 01). rMTT is 1.17 ±0.05, 1.04±0.04, 1.01 ±0.06 in ACA area, 1.41±0.06, 1.08±0.04, 1.07±0.04 in MCA area, 1.20±0.06, 1.06±0.04, 1.05±0.04 in basal ganglia, 1.41 ±0.05,1.10 ±0. 05, 1.09 ±0. 04 in front CWS area, 1.43 ±0. 10, 1.07 ±0. 06, 1.08 ±0. 06 in back CWS area,1.29±0.10, 1.09 ±0.05, 1.11 ±0.07 in IWS area (F=51.74, 248. 89, 70.08, 381.68, 288.94,41.53, P ＜0. 01 ). There were significant differences of rCBF and rMTT between those measured one week before CAS and one week or one year after CAS ( P ＜ 0. 01 ), but there were no significant differences of rCBF or rMTT in any area measured between those at 1 week after CAS and those measured at 1 year after CAS(P＞0.05). Conclusions Hemodynamic outcome at one year after CAS is good in the absence of contralateral carotid artery steno-occlusive disease. In addition, the coherence of results between 1-week and 1-year indicates that the outcome of one week after CAS could predict long-term hemodynamic outcome.

Objective To investigate the value of multi-slice computed tomography angiography (MSCTA)in the detection of intracranial micro-aneurysms(aneurysm≤3 mm in maximal diameter, IMA).Methods The clinical history and images of 826 patients with suspected intracranial aneurysms were retrospectively analyzed.All patients underwent MSCTA on 16-slice row CT before hospitalization(from 2 h to 4 d after symtom onset).All intracranial aneurysms were confirmed by digital subtraction angiography (DSA), three-dimensional rotational angiography (3DRA) or surgery.Two independent radiologists assessed all the images.The MSCTA findings were compared with the DSA/3DRA results.The sensitivity, specificity, and accuracy of MSCTA for diagnosis of IMA was calculated.The diagnostic consistency between DSA/3 DRA and MSCTA was determined by Kappa statistics.The prevalence of multiple aneurysms between the group of patients with IMA and the group of patients without IMA was evaluated by Chi-square test Results A total of 889 aneurysms in 788 of the 826 patients were detected.Among them, 706 patients had single aneurysm and 82 patients had multiple aneurysms.No aneurysms were detected in 38 patients.Among the 212 patients who underwent DSA/3 DRA, 271 aneurysms were found and 232 were IMA.MSCTAdetected 229 IMA.There was 1 false-positive finding and 4 false-negative findings by MSCTA.The sensitivity, specificity and accuracy of MSCTA for IMA was 98.3% (228/232), 97.4% (38/39), 98.2% (266/271).There was excellent agreement between two techniques (Kappa=0.927, P<0.05).The prevalence of multiple aneurysms was 21.2% (45/212) in the patient group with IMA and 6.4% (37/576) in the group without IMA.There was statistically significant difference between the two groups (X~2=36.421, P<0.01).Conclusions The detection value of IMA by MSCTA was high.The cutoff level of diameter of intracranial IMA should be adjusted from 4-5 mm to ≤3 mm.

Through introducing mutations into ribosomes by obtaining spontaneous drug resistance of microorganisms, ribosome engineering technology is an effective approach to develop mutant strains that overproduce secondary metabolites. In this study, ribosome engineering was used to improve the yield of butenyl-spinosyns produced by Saccharopolyspora pogona by screening streptomycin resistant mutants. The yields of butenyl-spinosyns were then analyzed and compared with the parent strain. Among the mutants, S13 displayed the greatest increase in the yield of butenyl-spinosyns, which was 1.79 fold higher than that in the parent strain. Further analysis of the metabolite profile of S13 by mass spectrometry lead to the discovery of Spinosyn α1, which was absent from the parent strain. DNA sequencing showed that there existed two point mutations in the conserved regions of rpsL gene which encodes ribosomal protein S12 in S13. The mutations occurred a C to A and a C to T transversion mutations occurred at nucleotide pair 314 and 320 respectively, which resulted in the mutations of Proline (105) to Gultamine and Alanine (107) to Valine. It also demonstrated that S13 exhibited genetic stability even after five passages.
Genetic Engineering ; Macrolides ; metabolism ; Point Mutation ; Ribosomal Proteins ; genetics ; Ribosomes ; metabolism ; Saccharopolyspora ; metabolism

Objective To evaluate the value of spiral CT volume reconstruetion(VR) technique in high complex anal fistula fistulography. Methods To analyze retrospectively internal openings and secondary tracts of 35 eases with high complex anal fistula verified by operation and follow-up above 3 months with VR,and compared with operation and outcome of follow-up. Results In 35 eases with high complex anal fistula, for detection of the presence of internal openings ,VR has a sensitivity of 72.7% ,a specificity of 100% ,a accuracy of 74.3% ,a positive predictive value of 100% ,and a negative predictive value of 18.1%. Secondary tracts have a sensitivity of 93.8% ,a specificity of 100.0% ,a accuracy of 94.6% ,a positive predictive value of 100.0% ,and a negative predictive value of 72.7%. Conclusion VR can demonstrate the 3D shape of fistula and is reliable in the diagnosis of internal openings and sec-ondary ducts, and is very valuable in the analysis of high complex anal fistula fistulography.