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Background Circulating cell-free DNA (cfDNA) methylation has been demonstrated to be a promising approach for non-invasive cancer diagnosis. However, the high cost of whole genome bisulfite sequencing (WGBS) hinders the clinical implementation of a methylation-based cfDNA early detection biomarker. We proposed a novel strategy in low-pass WGBS (~ 5 million reads) to detect methylation changes in circulating cell-free DNA (cfDNA) from patients with liver diseases and hepatocellular carcinoma (HCC). Methods The effective small sequencing depth were determined by 5 pilot cfDNA samples with relative high-depth WGBS. CfDNA of 51 patients with hepatitis, cirrhosis, and HCC were conducted using low-pass WGBS. The strategy was validated in an independent WGBS cohort of 32 healthy individuals and 26 early-stage HCC patients. Fifteen paired tumor tissue and buffy coat samples were used to characterize the methylation of hepatitis B virus (HBV) integration regions and genome distribution of cfDNA. Results A significant enrichment of cfDNA in intergenic and repeat regions, especially in previously reported HBV integration sites were observed, as a feature of cfDNA and the bias of cfDNA release. Methylation profiles nearby HBV integration sites were a better indicator for hypomethylation of tumor genome comparing to Alu and LINE (long interspersed nuclear element) repeats, and were able to facilitate the cfDNA-based HCC prediction. Hypomethylation nearby HBV integration sites (5 kb flanking) was detected in HCC patients, but not in patients with hepatitis and cirrhosis (MethylHBV5k, median:0.61 vs 0.72, P = 0.0003). Methylation levels of integration sites certain candidate regions exhibited an area under the receiver operation curve (AUC) value > 0.85 to discriminate HCC from non-HCC samples. The validation cohort achieved the prediction performance with an AUC of 0.954. Conclusions Hypomethylation around viral integration sites aids low-pass cfDNA WGBS to serve as a non-invasive approach for early HCC detection, and inspire future efforts on tumor surveillance for oncovirus with integration activity.

In this study, the process of electrospinning was combined with traditional spin process to fabricate twisted continuous nanofiber/cotton hybrid yarns. The morphologies and structures of the prepared polyacrylonitrile (PAN) nanofiber/cotton hybrid yarns were investigated. Results showed that the twisted hybrid yarns can withstand the abrasion in conventional textile processes such as spinning. This novel method has shown potential for the production of hybrid yarns consisting of nanofibers and cotton fibers for potential applications in the textile industry.

A novel free surface electrospining via a stepped pyramid-shaped spinneret was used to prepare composite nanofibers containing microparticles. We investigate the spinnability of Polyacrylonitrile (PAN) solution containing graphite powder microparticles. The influence of microparticle on fiber diameter has been studied. This method can be used to produce composite nanofibers containing microparticles structures by electrospinning in mass scale.

We experienced a case of a 36-year-old married man who was found to be hepatitis B virus (HBV) positive at 23 years of age. His liver function was repeatedly abnormal in the past 13 years. In November 2007 he presented with fatigue. Laboratory tests showed serum alanine aminotransferase concentration 255.3 U/l, positive for hepatitis B surface antigen (HBsAg) and hepatitis B e antibody, HBV DNA 3.01 × 10(7) copies/ml; liver biopsy showed necroinflammatory scores 11 and fibrosis scores 4. After 20 weeks of treatment with Peg-IFN α-2b, laboratory tests showed HBV DNA500 copies/ml and normal liver function. By week 52 of the treatment, HBsAg became negative. By week 92 of continuing treatment, HBsAb became weakly positive and Peg-IFN α-2b treatment was stopped. On follow-up, both HBsAg and HBsAb were negative 28 weeks after discontinuation of Peg-IFN α-2b. We then performed a second liver biopsy and histological examination revealed necroinflammtary scores 2 and fibrosis scores 2. We administered hepatitis B vaccine intramuscularly every 4 weeks combined with IFN α-1b 30 μg intramuscularly every other day. HBsAb was 244.8 IU/l at week 32 of this combined treatment. Follow-up showed that after discontinuation of the combined treatment HBsAb concentration declined rapidly but could be maintained above 100 IU/l by intermittent injections of hepatitis B vaccine. Findings from this case reveal that HBsAg loss may be not sufficient; however, HBsAg seroconversion together with maintenance of certain concentrations of HBsAb may be a better endpoint to HBV treatment.

This paper studied the effect of Mg-Nd alloys on the ignition-proof performance of AZ91D magnesium alloy. The results showed that 0.5%Nd decreased the ignition point of alloy for about 20°C, but the ignition point could been multiplied with the adding of Nd element. When the content of Nd reached 5%, the ignition point increased about 40°C compared with AZ91D alloy. The ignition point reduced after the addition of 0.5%Nd can be attributed to the decrease of the solidus temperature and liquidus temperature. The further analysis indicated Nd and Al formed Al3Nd first, which consumed the content of Nd, so that the alloy didn’t have enough Nd to form Nd2O3 to protecting the alloy. The EDS analysis indicated when the addition of Nd reached 5%, competent Nd2O3 could be formed and compact oxide film which consisted of Nd2O3, MgO and Al2O3 was formed to prevent alloys from oxidation and combustion.

The tube-shaped parts of A356 alloy were deformed from 0% to 83% by spinning process. The microstructure and mechanical properties of A356 alloy were discussed. The results showed that as the wall thickness reduction increases, the dendrite cells of cast alloy are lengthened gradually and the average Secondary Dendrite Arm Spacing (SDAS) is reduced from 37.2μm to 23μm and eutectic silicon particles are distributed orderly along the spinning direction. The coarse acicular β-Al5FeSi is broken into many sections, and its length is reduced from 37.5μm to 12.5μm in the cross-section. The tensile strength and elongation exhibit a strong dependence upon the variation in wall thickness, with a parabolic relationship. The tensile fractured surface of parts with deformation ratio above 35% exhibits many equiaxial dimples, with intergranular ductile fracture mode.

The type, shape and distribution of carbide take directly effect on the mechanical properties of high chromium castings. Vanadium is able to stabilize the structure of carbide in high chromium cast iron, meanwhile the hardness of carbide containing vanadium can reaches about 2800HV. In some cases, vanadium can also refine the microstructure. Rare-earth is able to change the shape of carbide in cast iron, refine the grain size of ferrite and improve the mechanical properties of castings. In this experiment, intention of adding vanadium and rare-earth is modification of mechanical properties with the proper heat treatment technology. With the help of SEM, the characteristics of carbide, such as shape, distribution and quantity can be observed and mechanical properties have been improved for better wear-resistance.

To investigate the perfusion characteristics and compare the volume of normal kidney and serum creatinine (Scr) before and after arterial embolization on 64-slice spiral CT.Totally 21 patients with renal tumor were enrolled. Sixty-four slice spiral CT was used for renal perfusion scan before and after patients underwent tumor arterial embolization. Perfusion characteristics, including blood flow, blood volume, and permeability of renal mass parenchyma and renal cortex in normal kidneys were calculated and the volume of normal kidneys was measured. The values of Scr in all patients were recorded. The perfusion characteristics, the volume of normal kidneys and the level of Scr before and after embolization were compared.Renal clear cell carcinoma was pathologically confirmed in all patients. After having supply blood arterial embolization of renal tumor, perfusion characteristics of tumor parenchyma significantly decreased, perfusion characteristics of renal cortex in normal kidney significantly increased, and the volume of normal kidneys was significantly enlarged (P0.01); however, the values of Scr in all patients were not significantly different (P0.05).The perfusion characteristics and volume of kidney may reflect the effects of renal arterial embolization on renal function. Perfusion imaging with multi-slice spiral CT is potentially useful in the evaluation of renal pathophysiological characteristics.

To compare the feasibility of bone and calcified plaque subtracted dual-energy CT angiography (CTA) with time of flight magnetic resonance angiography (TOF MRA) in evaluation of internal carotid artery atherosclerosis.Totally 32 patients received a dual-energy CTA scan, along with a cerebral TOF MRA scan before or after CTA examination from one day to one month. Dual-energy software was used for bone and calcified plaque subtraction. Five anatomical segments were described for each internal carotid artery according to Fischer (1938). Ratings were based on a 1-4 scale for the dual-energy CTA maximum intensity projection (MIP) image: 1 not diagnostic, 2 partially diagnostic, 3 diagnostic, and 4 excellent. Lesions were categorized as mild (0-29%), moderate (30%-69%), severe (70%-99%), or occluded (no flow detected). Stenosis of internal carotid artery was evaluated based on post-subtracted CTA images and TOF MRA images.In 320 arterial segments, 99% of arterial segments wereor = 3 score. Grading of stenosis on dual-energy CTA agreed with grading of stenoses on MRA images in 98% of arteries. In the mild and occlusion group, the agreement was 100% respectively. In the moderate and severe group, dual-energy CTA showed more severe stenosis than MRA in 7 vessels and there was significant difference between the results from the two different modalities (Z = -3.071, P = 0.002).Dual-energy CTA can be used to assess the stenosis of internal arteries around skull base, but may exaggerate the severe stenosis of cerebral arteries compared with TOF MRA.

To explore the relationship of the perfusion defects in the dual-energy CT lung perfusion image and the filling defects in the CT pulmonary angiography (CTPA) in patients with acute pulmonary embolism.The clinical data of 22 patients with acute pulmonary embolism were retrospectively analyzed. All of them underwent contrast CT scan in two phases using dual-energy CT: the first is pulmonary artery phase, and the second was performed immediately after the first phase using dual-energy scan covered the whole lung. Perfusion defects in the lung perfusion images were compared with the filling defects in the CTPA.Complete filling defects of segmental and subsegmental pulmonary arteries mostly showed correspondence perfusion defects in the CT perfusion map, accounting for 83% and 62% respectively. However, when there were partial or central filling defects, most of them were partial perfusion defects or normal in the CT perfusion map. Three segmental perfusion defects were depicted without the visualization of endoluminal thrombi within the corresponding arteries.The perfusion defects in the CT lung perfusion image are not completely corresponding to the filling defects in the CTPA. The combination of CTPA and CT lung perfusion map will offer more information for the acute pulmonary embolism.

To evaluate perfusion characteristics of normal renal cortex with 64-slice spiral CT and to investigate the correlation between perfusion parameters and gender, age, and serum creatinine (Scr).In total 71 healthy subjects, the kidney non-enhanced imaging and perfusion imaging with 64-slice spiral CT were performed. Perfusion parameters of renal cortex including blood flow (BF), blood volume (BV), and permeability (PM) were calculated with Siemens Body PCT (VB20B) software. The differences of BF, BV and PM in different age and gender people were compared by one-way ANOVA. The correlation between age and perfusion parameters, Scr, and PM were analyzed.Technical failures were experienced in 3 (3/71, 4.2%) subjects. Perfusion values of normal renal cortex in male, female, and all subjects were obtained separately. Male subjects (n = 56): BF = (229.8 +/- 49.9) ml/(100 ml x min), BV = (398.2 +/- 59.5) 1000:1, PM = (213.5 +/- 54.0) 0.5 ml/(100 ml x min); female subjects (n = 52): BF = (230.0 +/- 56.1) ml/(100 ml x min) BV = (358.1 +/- 49.7) 1000:1, PM = (186.2 +/- 32.1) 0.5 ml/(100 ml x min); all subjects (n = 108): BF = (229.9 +/- 52.7) ml/(100 ml x min), BV = (378.9 +/- 58.4) 1000:1, PM = (200.4 +/- 46.7) 0.5 ml/(100 ml x min). There was no significant difference in BF (F = 0.367, P = 0.547), BV (F = 3.088, P = 2.762), and PM (F = 3.308, P = 0.074) between male and female. In male, female, and all subjects, BF were all negatively correlated with age (r = -0.484, r = -0.429, r = -0.425; P0.01), while there was no correlation between BV (r = -0.152, r = -0.243, r = -0.043, P0.05) and PM (r = 0.053, r = 0.123, r = 0.172, P0.05) and age. There was no correlation between PM and Scr (r = 0.064, P0.05).The measurement of normal renal cortical perfusion characteristics with 64-slice spiral CT is feasible and can be used for the quantitative evaluation of the physiological functions of normal renal cortex.

To investigate the perfusion characteristics of renal mass parenchyma on 64-slice spiral computed tomography (CT).Totally 91 patients with renal mass were enrolled. Sixty-four slice spiral CT was used for renal perfusion scan that began with a contrast bolus injection of 50 ml (370 mgI/ml) at a rate of 5 ml/s. Perfusion characteristics, including blood flow (BF), blood volume (BV), and permeability (PM) of renal mass parenchyma and renal cortex in affected and normal kidneys were calculated from Siemens Body PCT (VB20B) software, and the perfusion characteristics among renal mass parenchyma and renal cortex in affected and normal kidneys were compared.Renal clear cell carcinoma (RC-CC), renal pelvic transitional cell carcinoma (RPTCC), and renal angiomyolipoma (RAML) was pathologically confirmed in 40, 21, and 16 patients, respectively, while the remaining 14 patients were diagnosed as with renal simple cyst (RSC). Technical failure was experienced in 1 (1.1% ) patient. Perfusion parameters of tumor parenchyma were measured as follow: RCCC, BF (93.7 +/- 20.2) ml x (100 ml)(-1) x min(-1), BV (182.0 +/- 46.6) 1000:1, PM (115.7 +/-30.2) 0.5 ml x (100 ml)(01) x min(-1); RPTCC, BF (48.0 +/- 21.2) ml x (100 ml)(-1) x min(-1), BV (82.4 +/- 29.7) 1000:1, PM (65.7 +/- 17.2) 0.5 ml (100 ml)(-1) x min(-1); RAML, BF (52.6 +/- 18.5) ml x (100 ml)(-1) x min(-1), BV (110.1 +/- 45.9) 1000:1, PM (60.1 +/- 23.0) 0.5 ml x (100 ml)(-1) x min-1; RSC, BF (7.0 +/- 6.5) ml x (100 ml)(-1) min(-1), BV (16.2 +/- 9.7) 1000:1, PM (12.0 +/- 7.2) 0.5 ml x (100 ml) (-1) x min(-1). In all pathological groups, perfusion pa- rameters showed significant differences (P0 . 1) between mass parenchyma and renal cortex in affected kidney, while there were no significant differences (P0. 5) in perfusion characteristics between renal cortex in affected and normal kidneys. Aslo, the perfusion characteristics were significantly different between parenchyma D in any two kinds of renal masses (P0 . 5) except for RPTCC and RAML (P0. 5). C ONCLUSIONS: fDif-rent pathological types of renal mass have different perfusion characteristics. Perfusion imaging with multislice CT is potentially useful in the differential diagnosis of renal mass.

Objective To review experience in preoperative detection of islet cell tumors using multislice computed tomography (MSCT) and summarize various imaging features of functioning islet cell tumors on enhanced MSCT. Methods Seventy patients with clinical or pathological diagnosis of functioning pancreatic islet cell tumor between October 2003 and February 2007 were included in this retrospective study. Seventy-four enhanced MSCT scans in these patients were identified. All MSCT scans were interpreted by two experienced radiologists by consensus interpretation. Surgery and pathology reports were used to confirm the diagnosis, localization, and size of tumors. Results Totally, 73 functioning islet cell tumors including 65 benign insulinomas, 2 benign glucagonomas, 3 malignant insulinomas, and 3 malignant glucagonomas were pathologically diagnosed. Tumors in only two cases were not found by MSCT. In 67 benign lesions, 32 showed typical enhancement style, 21 showed prolonged enhancement in portal venous phase, 4 showed delayed enhancement, 4 had iso-dense enhancement with normal pancreatic parenchyma, 2 had no enhancement at all in arterial phase and portal venous phase, and 4 had inhomogeneous enhancement with necrosis or cyst-formation. Patchy or spotty calcifications were found in 3 of the 67 tumors. In 6 malignant islet cell tumors, vessel invasion (2/6) and bowel invasion (1/6) were seen. Different enhancement patterns were shown. All hepatic metastases showed hyper-enhancement during their arterial phase. Conclusion Pancreatic islet cell tumor may display a wide spectrum of presentations in MSCT. Tumors with unusual appearances often present as diagnostic challenges. Non-contrast and post-contrast multiphase scans are recommended for the localization of functioning islet cell tumors.

To explore the imaging and related clinical characteristics of magnetic resonance (MR) delayed enhancement in patients with ischemic or nonischemic heart disease.Thirty-two cases who underwent MR myocardial cine and delayed enhancement imaging from January 2004 to October 2006 were retrospectively analyzed. The cine sequence imaging included the four-chamber view and the left ventricular short axis view. The delayed enhancement imaging was taken 10 minutes after the infusion of gadolinium from the antecubital vein with a segmented inversion-recovery-prepared T1-weighted fast gradient echo sequence. Patients underwent coronary computed tomography angiography (CTA) two weeks before or after the MR imaging examination. Combined with clinical history, the clinical and MR imaging characteristics of the patients who had delayed enhancement were analyzed.MR delayed enhancement could be found in 16 cases. Among them, 12 cases had ischemic heart disease. Their coronary CTA showed one to three vessel diseases. The delayed enhancement was transmural or subendocardium, and the area of delayed enhancement corresponded well with one or more coronary arteries which had severe stenosis or occlusion. Four cases had nonischemic heart diseases. One case was dilated cardiomyopathy, with diffuse small midwall spots in delayed enhancemen and only 30% stenosis of the anterior descending coronary artery in coronary CTA. One case was hypertrophic cardiomyopathy, with delayed enhancement of strip- and patch-shaped at midwall of the hypertrophic myocardium. One case was restrictive cardiomyopathy, and the delayed enhancement was located in the area of subendocardium of both the right and left ventricles. Coronary CTA of these two cases were normal. The other case was a mass of the lateral wall of the left ventricle, and the delayed enhancement with a clumpy shape was located in the lateral wall of the left ventricle.MR myocardial delayed enhancement is not a specific sign of myocardial infarction of ischemic heart disease. Nonischemic heart diseases including all kinds of primary cardiomyopathy and some other diseases affecting myocardium can also cause delayed enhancement, but their characteristics are different. The differentiation of the etiology of the nonischemic heart disease with delayed enhancement relies upon the intimate connection with clinical history and the cine sequence MR images.

To evaluate the utility of multi-slice spiral CT in the diagnosis of pulmonary hypertension.The clinical and multi-slice spiral CT data of 22 patients with pulmonary hypertension were retrospectively analyzed. The diagnoses included chronic thromboembolic pulmonary hypertension (CTEPH) (n = 9), primary pulmonary hypertension (PPH) (n = 7), connective tissue diseases (n = 2), portal-pulmonary hypertension (n = 2), eosinophilia-myalgia syndrome (n = 1), and fibrosing mediastinitis (n = 1). Lung parenchyma, such as ground-glass opacity, mosaic attenuation and septal thickness, mediastinum, pulmonary vascular, right ventricular enlargement and interventricular septum displacement were evaluated on CT.CT pulmonary angiography (CTPA) accurately diagnosed 95% of pulmonary hypertension and the signs of right ventricular dysfunction. Pulmonary embolism was found in 9 patients. The incidence of mosaic attenuation was significantly higher in CTECH than in PPH (P = 0.034).CTPA can accurately diagnose pulmonary hypertension and thereby provide useful information for the etiological diagnosis.

To study the clinical value of multi-slice spiral CT (MSCT) perfusion technique in evaluation of cerebral hemodynamics in patients with severe carotid stenooclusive lesions.Twenty-three patients with severe carotid stenosis were enrolled for evaluation of cerebral hemodynamics, including 12 patients with carotid occlusion and 11 with severe carotid stenosis (70%). Among them, 16 patients had multiple arterial diseases, including contralateral carotid stenosis, vertebral arteries stenosis, and cerebral arteries stenosis or occlusion. All patients received CT perfusion examination. Ten normal persons received CT perfusion were regarded as the control group.Cerebral perfusion was bilaterally symmetrical in 10 normal persons. While in the patients group, cerebral hemodynamic impairments ipsilateral to the stenosis side were found by CT perfusion in 17 patients, including an delay of time to peak (TTP) (17 patients), increase of cerebral blood volume (CBV) (7 patients), and decrease of cerebral blood flow (CBF) (4 patients). No significant difference was found between occlusion group (n = 8) and stenosis group (n = 9) (P = 0.640), but incidences of hemodynamic impairment were significantly higher in multiple arterial diseases group (n = 14) than single arterial disease group (n = 3) (P = 0.045).CT perfusion technique can sensitively reveal the cerebral hemodynamic impairments in patients with severe carotid stenooclusive diseases, and therefore valuable for clinical application.

To evaluate the clinical value of assessment of coronary stent patency by 64-slice spiral CT coronary angiography.Totally 29 patients (59 stents) were investigated using a retrospective ECG-gated enhanced scan by 64-slice spiral CT at a mean interval of (28.4 +/- 21.2) months after coronary stent implantation. Axial multi-planar reconstruction (MPR) of the stents and curved-planar reconstruction (CPR) through the stents were evaluated for image quality on a 5-point scale (1 = excellent, 5 = uninterpretable) and lumen diameter. Stent lumen diameter was compared with the vessel diameter proximal of the stents to assess the in-stent lumen visibility. Conventional coronary angiography was performed in 5 patients, and 9 stents were evaluated.The image quality was good to excellent on average (scores: 1.94 +/- 0.84), depending on heart rate, breath movement, and stent location. Stent lumen was visible, on average a percentage off (76.1 +/- 11.1)% of the lumen diameter. All the 9 stents were correctly detected as being patent, which was confirmed by conventional coronary angiography.64-slice spiral CT is a useful tool to assess the coronary stent patency.

To investigate the value of multi-slice spiral computed tomography (MSCT) in the determination of global left ventricular function.Twenty-nine patients with confirmed or suspected coronary heart diseases were imaged with a contrast-enhanced retrospective electrocardiogram (ECG) -gated technique on a 64-slice spiral CT scanner. The data sets were reconstructed at both end-diastolic and end-systolic phases in order to measure left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular stroke volume (LVSV), and left ventricular ejection fraction (LVEF). The results were compared with corresponding values obtained from conventional left ventriculography (LVG).LVEDV, LVESV, LVSV, and LVEF obtained with 64-slice spiral CT were significantly correlated with the LVG data (r = 0. 887-0.956, P0.001). According to the Bland-Altman approach, the mean differences for LVEDV, LVESV, LVSV, and LVEF were -2.3 ml, 4.1 ml, -6.4 ml, and - 3.5%, respectively. The limits of agreement for LVEDV, LVESV, LVSV, and LVEF were -27.2-22.4 ml, -10.2-18.4 ml, -26.4-13.6 ml, and -9.8%-3.0%, respectively.MSCT has clinically acceptable agreement with LVG for the quantification of global left ventricular function.

To compare the coronary artery bypass graft (CABG) imaging between 16-slice spiral CT and 64-slice spiral CT.Totally 27 patients with CABG received multi-slice spiral CT imaging and the results were retrospectively analyzed. Among them, 8 patients received 16-slice spiral CT scanning, 19 patients received 64-slice spiral CT scanning.The evaluability rates of 64-slice spiral CT in evaluating the proximal anastomosis, bypass graft, distal anastomosis, and distal blood vessel were 100%, 100%, 90.2%, and 93.9%, respectively, while those of 16-slice spiral CT were 92.3%, 95.2%, 90.0%, and 90.0%, respectively. The patency rates of the above four aspects of 64-slice spiral CT were 66.7%, 70.0%, 71.7%, and 70.0%, respectively, while those of 16-slice spiral CT were 83.3%, 85.0%, 83.3%, and 88.9% .64-slice spiral CT is superior to 16-slice spiral CT in CABG imaging. It can be used as a non-invasive tool for the post-operative follow-up of CABG.

To explore changes in the carotid arteries in Tarkayasu arteritis (TA) with computed tomographic angiography (CTA).The common carotid artery intima-medial thickness (CCA-IMT) in 20 common carotid arteries (CCAs) in 10 controls and 40 CCAs in 20 patients with TA were analyzed and compared.Contrast-enhanced CT scanning combined with the application of 3D reconstruction clearly showed the carotid vascular luminal abnormalities, such as stenosis, occlusion, dilation, and aneurysm formation. CCA-IMT increased in all the patients with TA affecting carotid arteries. CCA-IMT was significantly larger in the patients than in controls [(0.36 +/- 0.13) cm vs. (0.03 +/- 0.02) cm, P0.05] , and was significantly larger in patients with active diseases than in those without active diseases [(0.44 +/- 0.09) cm vs. (0.24 +/- 0.10) cm, P0.05].CCA-IMT increases in TA affecting carotid arteries, especially in active diseases.

To compare the image quality and visibility of arteries of 64-slice spiral coronary CT angiography (CTA) with those of 16-slice spiral coronary CTA, and to evaluate the diagnostic accuracy of 64-slice spiral CT for the assessment of coronary artery stenosis.Totally 100 patients (Group A) with suspected coronary artery diseases (CAD) were examined by 64-slice spiral CT, 48 of whom also underwent conventional coronary angiography (CAG). Another 100 patients (Group B) with suspected CAD were studied by 16-slice spiral CT. Patients with a heart rate above 70 bpm received oral beta-blockers before the scan. Data were retrospectively analyzed and reviewed by two observers. Image quality was assessed by using a 3-point grading scale from excellent (1) to non-assessable (3) and the rate of displayed coronary branches was calculated. The left main artery (LM), left anterior descending artery (LAD), circumflex artery (CX), and right coronary artery (RCA) were screened for the presence of over 50% stenosis.The mean heart rates of two groups showed no significant difference [(61 +/- 8) bpm vs. (61 +/- 7) bpm, P0.05]. The mean scan time of Group A was significantly shorter than that of Group B [(11.9 +/- 0.9) s vs. (22.2 +/- 1.1) s, P0.01]. In the evaluation of image quality, better results were obtained in Group A than in Group B (1.20 +/- 0.47 vs. 1.37 +/- 0. 63, P0.05). The visibility of proximal arteries was similar between two groups, while the visibility of some distal arteries and small branches was found higher in Group A than in Group B (LAD distal 92% vs. 48%, CX distal 98% vs. 89%, the first obtuse marginal (OMI) 93% vs. 84%, cone branch (CB) 86% vs. 71%, P0.05). Compared with CAG, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 64-slice spiral coronary CTA to identify over 50% stenosis were 94.9% (56/59), 93.2% (124/133), 86.2% (56/65), and 97.6% (124/127), respectively.With higher temporal and spatial resolution, 64-slice spiral CT provides improved image quality and visibility of small branches as compared with 16-slice spiral CT. 64-slice spiral coronary CTA allows reliable non-invasive diagnosis of obvious coronary artery stenosis.

To investigate the perfusion characteristics of normal pancreas and insulinoma on multi-slice spiral CT (MSCT).Totally 21 subjects with suspected insulinoma were enrolled. Sixteen-slice spiral CT was used for perfusion scan following a standard contrast-enhanced scan. The surgical and pathological outcomes were collected for comparison. Perfusion characteristics, including blood flow (BF), patlak blood volume (pBV), time to peak (TTP), permeability, and peak enhancement (PE) of insulinomas and normal pancreas parenchyma were analyzed based on the MSCT data sets subsequently.Benign insulinoma was pathologically confirmed in 12 out of the 21 subjects, while the remaining 9 subjects were normal. Technical failures were experienced in 2 (9.5%) subjects. In both normal and tumor-suffered subjects (n = 19), perfusion parameters of normal pancreatic parachyma were measured as follows: BF (p) = 104. 9 +/- 28.9, pBV (p) = 166.4 +/- 41.8, TrP (p) = 133.3 +/- 24.4, Permeability (p) = 81.3 +/- 24.4, and peak enhancement (p) = 121.3 +/- 31.1. In subjects with insulinoma (n = 11), perfusion parameters of tumor tissue were measured as follows: F (i) = 206.5 +/- 42.2, BV (i) = 315.9 +/- 79.0, TFP (i) = 123.2 +/- 18.8, Permeability (i) = 102.5 +/- 54. 8, and peak enhancement (i) = 221.3 +/- 48.5. Results of F, BV, and peak enhancement in these two kinds of tissue showed significant differences (P0.01), while there were no significant difference (P0.05) in TTP and permeability between normal pancreatic parenchyma and insulinoma.Benign insulinoma has perfusion characteristics of increased blood flow and blood volume, but its TTP is consistent with normal pancreas and has normal permeability. MSCT allows further understanding of the blood flow of the normal pancreas and its benign tumor insulinoma.

To evaluate the value of 16-slice spiral CT in the demonstration of coronary artery and in the diagnose of coronary artery stenosis.Plain and enhanced CT scans were performed with a 16-slice CT scanner (Sensation 16, Siemens, Germany) in 230 patients with suspected coronary heart disease (CHD). Parameters of the plain scan were: 120 kV, 133 mA, slice collimation 16 mm x 1.5 mm, rotation time 0.42 seconds, increment 1.5 mm, and slice width 3 mm. Parameters of the enhanced scan were: 120 kV, 500 mA, slice collimation 16 mm x 0.75 mm, rotation time 0.42 seconds, increment 0.5 mm, and slice width 1 mm. Enhanced CT scan was performed with a rapid intravenous injection of 100 mL iothalamate meglumine (Ultravist) (370 mgI/mL) or Omnipaque (350 mgI/mL) and 30 mL 0.9% NaCl chaser bolus at a flow rate of 3.5 mL/s. Calcium scoring with plain scan images and two and three dimensional reconstruction with enhanced scan images were made in all cases, among which 30 cases underwent conventional coronary angiography. Demonstration of coronary arteries and their stenosis were evaluated and the factors that might influence the image quality were analyzed.Coronary calcium scores were calculated and coronary artery was demonstrated in our study. In the evaluation of image quality with volume rendering technique (VRT) images, 78.3% of the images were of the first class, 12.2% the second class, and 9.6% the third class. Multi-planar reconstruction (MPR) and maximal intensity projection (MIP) were better than VRT in the demonstration of small branches. The image quality was related to the heart rate, with or without arrhythmia, and breath-hold ability of patients. Comparative study of the stenosis of coronary arteries in 30 cases showed that the sensitivity and specificity of 16-slice coronary CT angiography (CTA) to diagnose significant stenosis were 95.8% and 94.8% respectively.As a non-invasive and quick method, 16-slice coronary CTA is sensitive and specific to diagnose the stenosis of coronary arteries and can be used as a screening method in the diagnosis of CHD.

To evaluate the techniques and clinical applications of 16 multislice helical CT in colonic lesions.Eighty-one patients including 54 colorectal carcinomas, 5 adenomas, 1 non-Hodgkin's lymphoma, 6 inflammatory bowel diseases, and other 15 cases underwent volume scanning using 16 multislice helical CT. Four types of reconstruction included multiple planar reconstruction, shaded surface display, raysum, and CT virtual colonoscopy.Complete colon could be shown in all patients. The lesions' morphology, number, size, location, intestinal cavity, pericolonic changes, and other abdominal organs were satisfactorily shown by CT.Sixteen multislice helical CT colonography is a valuable imaging technique for detecting colonic diseases. It is effective in diagnosis and treatment planning. It can display the portions of colon that is inaccessible at colonoscopy.

To investigate the feasibility of multi-slice spiral CT (MSCT) for cholangiopancreatography without cholangio-contrast.Ten patients without any digestion system diseases and 24 patients with suspected pancreatic malignancy received the 16-slice spiral CT multi-phased contrast-enhanced scanning. The images of patients without any digestion system diseases and cancer-suffered patients were curved reformatted (CR) technique to perform the structure of pancreatic duct, common bile duct, and ampulla. The cholangiopancreatical systems of the cancer suffered patient were reconstructed through volume rendering technique (VRT), minimum intensity projection (MinIP), and indirect minimum intensity projection (IMinIP). The results of patients without any digestion system diseases in curved multiplanar reconstruction were analyzed; meanwhile display rates of the pancreatic duct, common bile duct, and ampulla were evaluated.of the four different cholangiopancreatographies were compared.The display rate of pancreatic duct in the CR images was 90.0 (9/10) with an average diameter of (2.63 +/- 0.51) mm. Sub-pancreatic duct could be seen in 88.9% (8/9) of them. The display rate of common bile duct in the CR images was 100% (10/10) with an average diameter of (7.45 +/- 1.12) mm. The display rate of ampulla was 60.0 (6/10), which was affected by the filling status of duodenum. The cholangiopancreatography using CR, VRT, MinIP, and IMinIP for patients with pancreatic cancer reveal the whole pancreatic and common bile duct, and the modality of distal obstructed bile duct. The result showed that IminIP got the best outcome (98.6%), while VRT got the worst (68.1%).The negative CT cholangiopancreatography is a simple and non-invasive examination. It reflects both the 3-dimensional cholangio-pancreatic anatomical structure and its adjacent condition. It has curtain clinical application values, especially for patients with obstructed duct system.

To evaluate the scanning technique and primary clinical value of sixteen-slice spiral CT coronary angiography.Plain and enhanced sixteen-slice spiral CT imaging was performed in 69 patients, including 64 cases of suspected coronary heart disease and 5 cases of coronary stent. Calcium scoring with plain scan images and MPR, MIP and VRT reconstruction with enhanced scan images were made in all cases, among which 10 underwent conventional coronary angiography. The demonstration and stenosis of coronary arteries were evaluated. The factors influencing the image quality were analyzed. Additional MPR and MIP reconstruction of slices perpendicular to the stent and virtual endoscopy of stent were made in 7 stents of the 5 cases of coronary stent. The patency of the stents was evaluated.A four-step scanning procedure was devised. Coronary calcium score could be got by plain scanning with sixteen-slice spiral CT angiography. All of the primary, most of the secondary and tertiary, and part of the fourth level branches of coronary artery could be shown isotropically with MPR, MIP and VRT reconstruction images of enhanced scanning. MPR and MIP were better than VRT in demonstrating small branches. Evaluated by VRT image, the image quality of 79.7% of the patients were first class, 10.1% second class, and 10.1% third class. The image quality was correlated to the contrast concentration in the root of aorta, heart rate, existence or absence of arrythmia, and the patient's breath-holding ability. Stenosis of coronary arteries was evaluated by sixteen-slice spiral CT imaging in 10 cases, with a result comparable to that by conventional coronary angiography. The stents were well shown, six stents being evaluated as patent, while one not.Sixteen-slice spiral CT coronary angiography is a noninvasive, simple and good method. Coronary calcium score and coronary artery stenosis can be evaluated with one study. The patency of stents can also be evaluated.

AIM: To evaluate the efficacy and safety of tolvaptan to treat refractory ascites in decompensated liver cirrhosis patients with or without further complications, such as hepatorenal syndrome and/or hepatocellular carcinoma. METHODS: Thirty-nine patients (mean age 55 years, males: 32) with decompensated liver cirrhosis and refractory ascites were enrolled. All patients received a combination of tolvaptan (15 mg/d for 5-14 d) and diuretics (40-80 mg/d of furosemide and 80-160 mg/d of spironolactone). The etiology of cirrhosis included hepatitis B (69.2%), hepatitis C (7.7%) and alcohol-induced (23.1%). Changes in the urine excretion volume, abdominal circumference and edema were assessed. The serum sodium levels were also measured, and adverse events were recorded. A follow-up assessment was conducted 1 mo after treatment with tolvaptan. RESULTS: Tolvaptan increased the mean urine excretion volume (1969.2 ± 355.55 mL vs 3410.3 ± 974.1 mL, P < 0.001), and 89.7% of patients showed improvements in their ascites, 46.2% of whom showed significant improvements. The overall efficacy of tolvaptan in all patients was 89.7%; the efficacies in patients with hepatocellular carcinoma and hepatorenal syndrome were 84.2% and 77.8%, respectively. The incidence of hyponatremia was 53.8%. In patients with hyponatremia, the serum sodium levels increased after tolvaptan treatment (from 128.1 ± 4.22 mEq/L vs 133.1 ± 3.8 mEq/L, P < 0.001). Only mild drug-related adverse events, including thirst and dry mouth, were observed. CONCLUSION: Tolvaptan is a promising aquaretic for the treatment of refractory ascites in patients with decompensated liver cirrhosis.

Background It is difficult to diagnose spontaneous bacterial peritonitis (SBP) early in decompensated liver cirrhotic ascites patients (DCPs). The aim of the study was to measure serum procalcitonin (PCT) levels and peripheral blood leukocyte/platelet (WBC/PLT) ratios to obtain an early diagnostic indication of SBP in DCPs. Methods Our cohort of 129 patients included 112 DCPs (94 of whom had infections) and 17 cases with compensated cirrhosis as controls. Bacterial cultures, ascitic fluid (AF) leukocyte and peripheral WBC/PLT counts, and serum PCT measurements at admission were carried out prior to the use of antibiotics. Receiver operating characteristic (ROC) curves were generated to test the accuracies and cut-off values for different inflammatory markers. Results Among the 94 infected patients, 66 tested positive by bacterial culture, for which the positivity of blood, ascites and other secretions were 25.8%, 30.3% and 43.9%, respectively. Lung infection, SBP and unknown sites of infection accounted for 8.5%, 64.9% and 26.6% of the cases, respectively. Serum PCT levels (3.02 ± 3.30 ng/mL) in DCPs with infections were significantly higher than those in control patients (0.15 ± 0.08 ng/mL); p