Objective To explore the characteristics and the clinical application of MR perfusion weighted imaging(PWI)in the normal kidneys and the renal diseases.Methods Thirty-one subjects including 9 cases without urinary diseases,14 cases with renal carcinoma,6 cases with renal cyst and 2 cases witll renal tuberculosis who had been examined with T1WI,T2WI and PWI were analyzed retrospectively.All the data were processed by a workstation to obtain time-signal intensity curves,color perfusion maps and relative perfusion value.The relative renal blood volume(RBV),relative renal blood flow(RBF),mean transition time(MTT)and the time to peak(TTP)in the normal renal cortex and medulla and the renal lesions were calculated.Comparisons between the right and the left normal kidneys,and between the cortex and the medulla of the normal kidneys were performed using t test,and comparisons between the normal and the abnormal kidneys were performed using q test.Results Relative RBV and relative RBF of the cortex were 1.33±0.08 and 1.44±0.09 respectively,and for medulla were 0.58±0.05 and 0.78±0.13 respectively(t=9.2241 and 5.0336,P＜0.01);MTT(1.11±0.08)and TTP (1.04±0.06)of the cortex has no difference with that of the medulla(0.97±0.04 and 0.94±0.03)in the normal kidneys(t=2.2551 and 2.2613.P＞0.05).The values of relative RBF of the renal carcinoma (1.35±0.34)were significantly higher than that of the normal tissues(1.02±0.06)(q=3.0882,P＜0.01).Conclusion PWI is able to demonstrate the hemodynamic change of the normal renal tissues and the renal lesions,and it maybe an ideal method for showing the functional changes of the kidney and for differentiating the renal diseases.

A stable dark variant separated from photobacterium phosphoreum (A2) was fixed in agar-gel membrane and immobilized onto an exposed end of a fiber-optic linked with bioluminometer. The variant could emit a luminescent signal in the presence of genotoxic agents, such as Mitomycin C (MC). The performance of this whole-cell optical fiber sensor system was examined as a function of several parameters, including gel probe thickness, bacterial cell density, and diameter of the fiber-optic core and working temperature. An optimal response to a model genotoxicant, Mitomycin C, was achieved with agar-bacterial gel membrane: the thickness of gel membrane was about 5 mm; the cell density of bacteria in gel membrane was about 2.0 x 10(7)/ml; the diameter of fiber-optic core was 5.0 mm; the working temperature was 25 degrees C. Under these optimized conditions, the response time was less than 10 h to Mitomycin C, with a lower detection threshold of 0.1 mg/L.
Biosensing Techniques ; Chemiluminescent Measurements ; Fiber Optics ; Luminescent Proteins/*genetics ; Mitomycin/*pharmacology ; Mitomycin/toxicity ; Photobacterium/*genetics ; Transcription, Genetic/drug effects ; Variation (Genetics)

Objective To explore the effects of ureteral stent on renal pelvic pressure and other urodynamic parameters. Methods Forty-one patients, 28 males and 13 females, with unilateral renal calculi and/or ureteral calculi were recruited in this study. The mean patient age was 47 years old (ranging from 20 to 72 years old). All cases were placed a 4.7 F ureteral stent and 16 F nephrostomy tube after minimal invasive pereutaneona nephrolithotomy (MPCNL). There was no hydronephrosis and residual crushed stone in the ureter after MPCNL in all cases. Renal pelvic pressure, intra-abdo minal pressure, detrusor pressure, bladder pressure changes during the filling and voiding phases with intravesical perfusion flow rate of 40 ml/min were recorded and analyzed. Results At the baseline, IPP0, IAP0, DP0 and BP0 were (33.1±17.0)cm H2O, (27.5±7.0)cm H2O, (3.3±2.9)cm H2O and (30. 9±7.2)cm H2O, respectively; At the maximum cystometric capacity during the filling phase, IPPvol, IAPvol Dpvol and Bpvol were (39.4±67. 3)cm H2O, (31.1±7.3)cm H2O, (10.7±6. 6) cm H2O and (41.6±10.3)cm H2O, respectively; At the maximum bladder pressure during the voiding phase, IPPmax, IAPmax Dpmax and Bpmax were (65.7±17.0)cm H2O, (33.7±9. 7)cm H2O, (41.9±7.8)cm H2O and (75.0±12. 8)cm H2O, respectively;There were statistical significance comparing between any of IPP0, IPPvol and IPPmax(P<0. 01). 27% (11/41)patients were with the pain in kidney area at voiding IPPmax (87.1±14.6) cm H2O, which was significantly higher than IPPmax (57.8±9.5)cm H2O of asyrnptomatic group (30 patients)(P<0. 01). In all cases, the renal pelvic pressure was higher than 40 cm H2O during the voiding phase. Conclusions Renal pelvic pressure increases during the filling phase after placing the ureteral stent, especially during the voiding phase. As renal function will be damaged by the high renal pelvic pressure, we should decrease the utilization of ureteral stent if possible. It is encouraged to remove the ureteral stent as early as possible.

Objective To evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL), retrograde ureterolithotripsy(URSL) and percutaneous ureterolithotripsy(PCL) in the treatment of proximal ureteral calculi. Methods A total of 397 patients with proximal ureteral calculi treated by ESWL,URSL or PCL ftom September 2001 to December 2005 were retrospectively analyzed. Results Among 397 patients,83 patients with a mean stone size of 1.23 cm were treated by ESW L.Of then.13 patients transferred to URSL or ureterolithotomy and the stone-free rate of ESWL 1 month later was 65.7%(46/70).TWO hundred and thirteen patients with a mean stone size of 1.21 cm were treated by URSL and 101 patients with a mean stone size of 1.50 cm were treated by PCL.The stone-free rate of URSL and PCL 1 month after the treatment was 88.2%(172/195)and 96.9%(95/98),respectively.Eighteen patients in URSL group and 3 patients in PCL group trans-ferred to ureterolithotomy.ESWL had a statistically lower stone-free rate than that of URSL and PCL (P＜0.001),both in patients with stone size≤1 cm and＞1 cm.For patients with stone size＞1 cm,PCL achieved a higher stone-free rate than URSL(P=0.005).PCL also had a higher stone-free rate than URSL in treating patients with stone size≤1 cm but there was no statistical difference between them. Conclusions ESWL can still be used as first-line treatment choice for proximal ureteral stones less than 1cm.For patients with proximal ureteral stones larger than 1cm.URSL and PCL are more proper treatment modalities since they can achieve higher stone-free rate and have acceptable low complications.

A stable dark variant separated from photobacterium phosphoreum (A2) was fixed in agar-gel membrane and immobilized onto an exposed end of a fiber-optic linked with bioluminometer. The variant could emit a luminescent signal in the presence of genotoxic agents, such as Mitomycin C (MC). The performance of this whole-cell optical fiber sensor system was examined as a function of several parameters, including gel probe thickness, bacterial cell density, and diameter of the fiber-optic core and working temperature. An optimal response to a model genotoxicant, Mitomycin C, was achieved with agar-bacterial gel membrane: the thickness of gel membrane was about 5 mm; the cell density of bacteria in gel membrane was about 2.0 x 10(7)/ml; the diameter of fiber-optic core was 5.0 mm; the working temperature was 25 degrees C. Under these optimized conditions, the response time was less than 10 h to Mitomycin C, with a lower detection threshold of 0.1 mg/L.
Biosensing Techniques ; Fiber Optic Technology ; Genetic Variation ; Luminescent Measurements ; Luminescent Proteins ; genetics ; Mitomycin ; pharmacology ; toxicity ; Optical Fibers ; Photobacterium ; genetics ; Transcription, Genetic ; drug effects

In this paper, a novel registration method is presented for three-dimensional mapping of cardiac chambers and computed tomography (CT) segmented surfaces. The proposed method applies random perturbations to three-dimensional mapping of cardiac chambers in order to move out of local minima. It effectively solves the problem of the existing algorithm based on iterative closest point (ICP) in which the optimization often falls into local minima, and improves the registration accuracy and success rate. The registration experiment results show that the final registration accuracy and success rate of the proposed method are better than the existing ICP-based algorithm, and it can implement the registration when the three-dimensional mapping of cardiac chambers and CT segmented surface have a wide range of initial offset.
Algorithms ; Heart ; diagnostic imaging ; Humans ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; Pattern Recognition, Automated ; methods ; Tomography, X-Ray Computed ; methods