Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging (MRI) T1 mapping images, as well as T1-weighted (T1W), T2-weighted (T2W) and apparent diffusion coefficient (ADC) maps for distinguishing between varying degrees of hepatic fibrosis in an experimental rat model.Methods Liver fibrosis in rats was induced by carbon tetrachloride intraperitoneal injection for 4-12 weeks (n=30). In the control group (n=10) normal saline was applied. The MRI protocol contained T2W, diffusion weighted imaging, pre-and post-contrast image series of T1W and T1 mapping images. METAVIR score was used to grade liver fibrosis as normal (F0), mild fibrosis (F1-2), and advanced fibrosis (F3-4). Texture parameters including mean gray-level intensity (Mean), standard deviation (SD), Entropy, mean of positive pixels (MPP), Skewness, and Kurtosis were obtained. Nonparametric Mann-Whitney U test was used to compare the average value of each texture parameter in each sequence for assessing the difference between F0 and F≥1 as well as F0-2 and F3-4. Receiver operating characteristic (ROC) curves were obtained to assess the diagnosing accuracy of the parameters for differentiating no liver fibrosis from liver fibrosis and rats with liver fibrosis grading F0-2 from those with grading F3-4. The area under ROC curve (AUC) was calculated to evaluate the diagnostic efficiency of texture parameters.Results Finally, 20 rats completed MR T1 mapping image scan. The pathologic staging of these 20 rats was no fibrosis (F0, n=6), mild fibrosis (F1-2, n=5) and advanced fibrosis (F3-4, n=9). On pre-contrast T1 mapping image, Entropy was seen to be statistically significant higher in the F≥1 group than that in the F0 group at each spatial scaling factor (SSF) setting (P=0.015, 0.015, 0.015, 0.013, 0.015 and 0.018 respectively to SSF=0, 2, 3, 4, 5, 6), and Mean of the F≥1 rats was statistically significant higher than that of the F0 rats at SSF 4, 5, 6 (P=0.004, 0.006, and 0.013, respectively). Entropy and Mean showed a moderate diagnostic performance in most SSF settings of T1 mapping pre-contrast images for differentiation of normal liver from liver fibrosis.Conclusions Certain texture features of gadoxetic acid-enhanced MR images, especially the Entropy of non-contrast T1 mapping image, was found to be a useful biomarker for the diagnosis of liver fibrosis.
Animals ; Contrast Media ; pharmacology ; Diffusion Magnetic Resonance Imaging ; Disease Models, Animal ; Gadolinium DTPA ; pharmacology ; Liver Cirrhosis ; diagnostic imaging ; physiopathology ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study the prevention effect of salidroside on contrast-induced-nephropathy (CIN) and its underlying mechanism.

METHODSA total of 24 Wistar rats were randomly divided into 4 groups with 6 in each group. Rats were firstly administrated with normal saline (control and model groups), N-acetylcysteine (NAC, NAC group) and salidroside (salidroside group) for 7 days before model establishment in each group, respectively. Histopathological analysis was performed by periodic acid-Schiff (PAS) staining. Oxidative stress related parameters including superoxide dismutase (SOD) and methane dicarboxylic aldehyde (MDA), nitric oxide (NO), angiotensin II (Ang II), 8-hydroxy-2'-deoxyguanosine (8-OHdG), mRNA and protein levels of endothelial nitric oxide synthase (eNOS), and nitric oxide synthase (NOS) activity were measured.

RESULTSCompared with the control group, the levels of MDA, Ang II and 8-OHdG were all significantly increased and levels of SOD, NO, and eNOS mRNA and protein were decreased significantly in the model group (P<0.05). Meanwhile, the NOS activity was also significantly decreased in the model group (P<0.05). In addition, the levels of these parameters were all improved in the NAC (P<0.05) and salidroside groups and no significant different was found between these two groups (P>0.05).

CONCLUSIONSalidroside can be the potential substitute of NAC to prevent CIN. The underlying mechanism may be associated with oxidative stress damage caused by contrast agents.

Acetylcysteine ; pharmacology ; Animals ; Contrast Media ; adverse effects ; Cytoprotection ; drug effects ; Glucosides ; pharmacology ; Kidney ; drug effects ; pathology ; Kidney Diseases ; chemically induced ; prevention & control ; Oxidative Stress ; drug effects ; Phenols ; pharmacology ; Rats ; Rats, Wistar ; Signal Transduction ; drug effects

PURPOSE: This study was performed to examine the treatment of erectile dysfunction by use of superparamagnetic iron oxide nanoparticles-labeled human mesenchymal stem cells (SPION-MSCs) transplanted into the cavernous nerve injured cavernosa of rats as monitored by molecular magnetic resonance imaging (MRI). MATERIALS AND METHODS: Eight-week-old male Sprague-Dawley rats were divided into three groups of 10 rats each: group 1, sham operation; group 2, cavernous nerve injury; group 3, SPION-MSC treatment after cavernous nerve injury. Immediately after the cavernous nerve injury in group 3, SPION-MSCs were injected into the cavernous nerve injured cavernosa. Serial T2-weighted MRI was done immediately after injection and at 2 and 4 weeks. Erectile response was assessed by cavernous nerve stimulation at 2 and 4 weeks. RESULTS: Prussian blue staining of SPION-MSCs revealed abundant uptake of SPION in the cytoplasm. After injection of 1x10(6) SPION-MSCs into the cavernosa of rats, T2-weighted MRI showed a clear hypointense signal induced by the injection. The presence of SPION in the corpora cavernosa was confirmed with Prussian blue staining. At 2 and 4 weeks, rats with cavernous nerve injury had significantly lower erectile function than did rats without cavernous nerve injury (p<0.05). The group transplanted with SPION-MSCs showed higher erectile function than did the group without SPION-MSCs (p<0.05). The presence of SPION-MSCs for up to 4 weeks was confirmed by MRI imaging and Prussian blue staining in the corpus cavernosa. CONCLUSIONS: Transplanted SPION-MSCs existed for up to 4 weeks in the cavernous nerve injured cavernosa of rats. Erectile dysfunction recovered and could be monitored by MRI.
Animals ; Contrast Media/pharmacology ; Dextrans/*pharmacology ; Disease Models, Animal ; Drug Delivery Systems/methods ; *Erectile Dysfunction/diagnosis/etiology/therapy ; Magnetic Resonance Imaging/methods ; *Magnetite Nanoparticles ; Male ; Mesenchymal Stem Cell Transplantation/*methods ; Monitoring, Physiologic/methods ; Penis/*innervation ; *Peripheral Nerve Injuries/complications/diagnosis/physiopathology/therapy ; Rats ; Suspensions ; Treatment Outcome

OBJECTIVETo evaluate whether garlicin can prevent reperfusion no-reflow in a catheter-based porcine model of acute myocardial infarction (AMI).

METHODSTwenty-two male Chinese mini swines were randomized into 3 groups: sham-operation group (n=6), control group (n=8), and garlicin group (n=8). The distal part of left anterior descending coronary artery (LAD) in swines of the latter two groups was completely occluded by dilated balloon for 2 h and a successful AMI model was confirmed by coronary angiography (CAG) and electrocardiograph (ECG), which was then reperfused for 3 h. In the sham-operation group, balloon was placed in LAD without dilatation. Garlicin at a dosage of 1.88 mg/kg was injected 10 min before LAD occlusion until reperfusion for 1 h in the garlicin group. To assess serial cardiac function, hemodynamic data were examined by catheter method before AMI, 2 h after occlusion and 1, 2, and 3 h after reperfusion. Myocardial contrast echocardiography (MCE) and double staining with Evans blue and thioflavin-S were performed to evaluate myocardial no-reflow area (NRA) and risk area (RA).

RESULTSLeft ventricular systolic pressure and left ventricular end-diastolic pressure significantly improved in the garlicin group after reperfusion compared with the control group P<0.05) and 2 h after AMI (P<0.05). MCE showed garlicin decreased reperfusion NRA after AMI compared with the control group (P <0.05). In double staining, NRA/RA in the garlicin group was 18.78%, significantly lower than that of the control group (49.84%, P<0.01).

CONCLUSIONSGarlicin has a preventive effect on the porcine model of myocardial infarction reperfusion no-reflow by improving hemodynamics and decreasing NRA.

Allyl Compounds ; pharmacology ; therapeutic use ; Animals ; Cardiotonic Agents ; pharmacology ; therapeutic use ; Contrast Media ; Disease Models, Animal ; Disulfides ; pharmacology ; therapeutic use ; Hemodynamics ; drug effects ; Male ; Myocardial Infarction ; complications ; diagnostic imaging ; drug therapy ; pathology ; Myocardial Reperfusion ; No-Reflow Phenomenon ; complications ; diagnostic imaging ; drug therapy ; pathology ; Swine ; Swine, Miniature ; Thiazoles ; metabolism ; Ultrasonography

PURPOSE: To investigate the correlations between parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and prognostic factors in rectal cancer. MATERIALS AND METHODS: We studied 29 patients with rectal cancer who underwent gadolinium contrast-enhanced, T1-weighted DCE-MRI with a three Tesla scanner prior to surgery. Signal intensity on DCE-MRI was independently measured by two observers to examine reproducibility. A time-signal intensity curve was generated, from which four semiquantitative parameters were calculated: steepest slope (SLP), time to peak (Tp), relative enhancement during a rapid rise (Erise), and maximal enhancement (Emax). Morphologic prognostic factors including T stage, N stage, and histologic grade were identified. Tumor angiogenesis was evaluated in terms of microvessel count (MVC) and microvessel area (MVA) by morphometric study. As molecular factors, the mutation status of the K-ras oncogene and microsatellite instability were assessed. DCE-MRI parameters were correlated with each prognostic factor using bivariate correlation analysis. A p-value of <0.05 was considered significant. RESULTS: Erise was significantly correlated with N stage (r=-0.387 and -0.393, respectively, for two independent data), and Tp was significantly correlated with histologic grade (r=0.466 and 0.489, respectively). MVA was significantly correlated with SLP (r=-0.532 and -0.535, respectively) and Erise (r=-0.511 and -0.446, respectively). MVC was significantly correlated with Emax (r=-0.435 and -0.386, respectively). No significant correlations were found between DCE-MRI parameters and T stage, K-ras mutation, or microsatellite instability. CONCLUSION: DCE-MRI may provide useful prognostic information in terms of histologic differentiation and angiogenesis in rectal cancer.
Adult ; Aged ; Aged, 80 and over ; Cell Differentiation ; Contrast Media/*pharmacology ; DNA Mutational Analysis ; Female ; Gadolinium/pharmacology ; Genes, ras ; Humans ; Magnetic Resonance Imaging/*methods ; Male ; Microcirculation ; Microsatellite Instability ; Middle Aged ; Neoplasm Staging ; Neovascularization, Pathologic ; Prognosis ; Rectal Neoplasms/*diagnosis/genetics/*pathology ; Retrospective Studies ; Time Factors

OBJECTIVE: The purpose of this study was to establish a minimally invasive and reproducible protocol for estimating the gastrointestinal (GI) transit time in mice using barium and radiopaque markers. MATERIALS AND METHODS: Twenty 5- to 6-week-old Balb/C female mice weighing 19-21 g were used. The animals were divided into three groups: two groups that received loperamide and a control group. The control group (n = 10) animals were administered physiological saline (1.5 mL/kg) orally. The loperamide group I (n = 10) and group II (n = 10) animals were administered 5 mg/kg and 10 mg/kg loperamide orally, respectively. Thirty minutes after receiving the saline or loperamide, the mice was administered 80 microL of barium solution and six iron balls (0.5 mm) via the mouth and the upper esophagus by gavage, respectively. Afterwards, the mice were continuously monitored with fluoroscopic imaging in order to evaluate the swallowing of the barium solution and markers. Serial fluoroscopic images were obtained at 5- or 10-min intervals until all markers had been excreted from the anal canal. For analysis, the GI transit times were subdivided into intestinal transit times (ITTs) and colon transit times (CTTs). RESULTS: The mean ITT was significantly longer in the loperamide groups than in the control group (p < 0.05). The mean ITT in loperamide group II (174.5 +/- 32.3) was significantly longer than in loperamide group I (133.2 +/- 24.2 minute) (p < 0.05). The mean CTT was significantly longer in loperamide group II than in the control group (p < 0.05). Also, no animal succumbed to death after the experimental procedure. CONCLUSION: The protocol for our study using radiopaque markers and barium is reproducible and minimally invasive in determining the GI transit time of the mouse model.
Analysis of Variance ; Animals ; Barium Sulfate/pharmacology ; Contrast Media/administration & dosage ; Female ; Fluoroscopy ; Gastrointestinal Transit/*physiology ; Iron ; Loperamide/administration & dosage ; Mice ; Mice, Inbred BALB C ; Microscopy, Electron, Scanning ; Prostheses and Implants ; Reproducibility of Results ; Sodium Chloride/administration & dosage ; Surface Properties

OBJECTIVETo evaluate the efficacy of atorvastatin in preventing contrast agent-induced nephropathy (CIN) in patients undergoing coronary angiography and explore the mechanism.

METHODSA total of 180 patients undergoing coronary angiography or percutaneous coronary interventions (PCI) were randomized into regular dose and high dose atorvastatin groups (n=90). Serum creatinine (Scr), glomerular filtration rate (GFR), cystatin, peripheral blood levels of myeloperoxidase (MPO), malondialdehyde (MDA), and superoxide dismutase (SOD) before and after the procedure were compared between the two groups.

RESULTSThe incidence of CIN was significantly lower in high-dose atorvastatin group than in the regular dose group. At 48-72 h after the surgery, serum Scr and cystatin levels were significantly lower and eGFR was significantly higher in the high-dose group. At 24 h after the surgery, MPO and MDA levels were significantly lower, and SOD activity was significantly higher in high-dose group than in the regular dose group.

CONCLUSIONHigh-dose atorvastatin used before angiography is more effective than the regular dose in attenuating contrast agent-induced renal dysfunction, and its mechanism is related with the inhibition of oxidative stress.

Aged ; Atorvastatin Calcium ; Contrast Media ; adverse effects ; Coronary Angiography ; adverse effects ; Female ; Heptanoic Acids ; administration & dosage ; pharmacology ; therapeutic use ; Humans ; Kidney Diseases ; chemically induced ; prevention & control ; Male ; Middle Aged ; Oxidative Stress ; drug effects ; Pyrroles ; administration & dosage ; pharmacology ; therapeutic use

OBJECTIVETo evaluate the protective effect of amlodipine against contrast agent-induced renal injury in elderly patients with coronary heart disease.

METHODSA total of 189 elderly patients (>60 years) with coronary heart disease undergoing coronary artery angiography were randomly assigned into amlodipine group and control group to receive amlodipine or placebo, respectively, before and after administration of the contrast agent. At 24 h, 48 h and 5 days after contrast agent administration, the parameters of renal function were measured including serum cystatin C, urea nitrogen, creatinine, creatinine clearance rate, urine β2-microglobulin, and urine N-acetyl-β-glucosaminidase.

RESULTSIn both groups, the contrast agents obviously affected the renal functions of the patients (P<0.05). At 24 h after contrast administration, the levels of serum cystatin C, urine β2-microglobulin and urine NAG were significantly lower in amlodipine group than in the control group, but the other functional parameters showed no significant difference. At 48 h after contrast administration, the glomerular and tubular functional parameters were all superior in amlodipine group (P<0.05). At 5 days, the two groups showed significant differences in such glomerular and tubular functional parameters as urea nitrogen, creatinine, creatinine clearance rate, urine β2-microglobulin, and urine NAG (P<0.05), but not in serum cystatin C level. The incidence of contrast agent-induced nephropathy was significantly lower in amlodipine group than in the control group (5/95 vs 10/94, P<0.05).

CONCLUSIONSAmlodipine offers protection against radiographic contrast agent-induced renal injury in elderly patients with coronary heart disease.

Aged ; Amlodipine ; pharmacology ; therapeutic use ; Contrast Media ; adverse effects ; pharmacology ; Coronary Angiography ; Coronary Disease ; diagnostic imaging ; Female ; Humans ; Kidney Diseases ; chemically induced ; drug therapy ; Kidney Function Tests ; Male ; Middle Aged

INTRODUCTIONWe compared the effectiveness of different types of non-commercial neutral oral contrast agents for bowel distension and mural visualisation in computed tomographic (CT) enterography.

METHODS90 consecutive patients from a group of 108 were randomly assigned to receive water (n = 30), 3.8% milk (n = 30) or 0.1% gastrografin (n = 30) as oral contrast agent. The results were independently reviewed by two radiologists who were blinded to the contrast agents used. The degree of bowel distension was qualitatively scored on a four-point scale. The discrimination of bowel loops, mural visualisation and visualisation of mucosal folds were evaluated on a 'yes' or 'no' basis. Side effects of the various agents were also recorded.

RESULTS3.8% milk was significantly superior to water for bowel distension (jejunum, ileum and terminal ileum), discrimination of bowel loops (jejunum and ileum), mural visualisation and visualisation of mucosal folds (ileum and terminal ileum). It was also significantly superior to 0.1% gastrografin for bowel distension, discrimination of bowel loops, mural visualisation and visualisation of mucosal folds (jejunum, ileum and terminal ileum). However, 10% of patients who received 3.8% milk reported immediate post-test diarrhoea. No side effects were documented for patients who received water and 0.1% gastrografin.

CONCLUSION3.8% milk is an effective and superior neutral oral contrast agent for the assessment of the jejunum, ileum and terminal ileum in CT enterography. However, further studies are needed to explore other suitable oral contrast agents for CT enterography in lactose- or cow's milk-intolerant patients.

Administration, Oral ; Adult ; Aged ; Aged, 80 and over ; Animals ; Contrast Media ; pharmacology ; Diatrizoate Meglumine ; pharmacology ; Female ; Humans ; Intestines ; diagnostic imaging ; drug effects ; Male ; Middle Aged ; Milk ; Multidetector Computed Tomography ; instrumentation ; methods ; Water

OBJECTIVE: Arsenic trioxide (As2O3) can be used as a possible pharmaceutical alternative that augments radiofrequency (RF) ablation by reducing tumor blood flow. The aim of this study was to assess the effect of intraarterial and intravenous administration of As2O3 on RF-induced ablation in an experimentally induced liver tumor. MATERIALS AND METHODS: VX2 carcinoma was grown in the livers of 30 rabbits. As2O3 (1 mg/kg) was administered through the hepatic artery (n = 10, group A) or ear vein (n = 10, group B), 30 minutes before RF ablation (125 mA +/- 35; 90 +/- 5degrees C). As a control group, 10 rabbits were treated with RF ablation alone (group C). RF was intentionally applied to the peripheral margin of the tumor so that ablation can cover the tumor and adjacent hepatic parenchyma. Ablation areas of the tumor and adjacent parenchymal changes among three groups were compared by the Kruskal-Wallis and Mann-Whitney U test. RESULTS: The overall ablation areas were 156 +/- 28.9 mm2 (group A), 119 +/- 31.7 (group B), and 92 +/- 17.4 (group C, p < 0.04). The ablation area of the tumor was significantly larger in group A (73 +/- 19.7 mm2) than both group B (50 +/- 19.4, p = 0.02) and group C (28 +/- 2.2, p < 0.01). The ratios of the tumoral ablation area to the overall ablation area were larger in group A (47 +/- 10.5%) than that of the other groups (42 +/- 7.3% in group B and 32 +/- 5.6% in group C) (p < 0.03). CONCLUSION: Radiofrequency-induced ablation area can be increased with intraarterial or intravenous administration of As2O3. The intraarterial administration of As2O3 seems to be helpful for the selective ablation of the tumor.
Animals ; Arsenicals/*pharmacology ; Catheter Ablation/*methods ; Combined Modality Therapy ; Contrast Media/diagnostic use ; Disease Models, Animal ; Liver/radiography ; Liver Neoplasms, Experimental/*drug therapy/radiography/*surgery ; Oxides/*pharmacology ; Rabbits ; Statistics, Nonparametric ; Tomography, X-Ray Computed