The incidence of life-threatening anaphylactoid reactions during anesthesia has been increasing. Specific allergic reactions during anesthesia are usually due to muscle relaxants, barbiturates, local anesthetics, narcotics, radiocontrast media, antibiotics, and colloids. Thrombokinase, a hemostatic agent, has been used widely in clinical practice and severe anaphylactoid reactions to thrombokinase can occur rarely. We experienced two cases of anaphylactoid reactions after thrombokinase administration.
Anesthesia ; Anesthetics, Local ; Anti-Bacterial Agents ; Barbiturates ; Colloids ; Contrast Media ; Factor Xa* ; Hypersensitivity ; Incidence ; Narcotics ; Pharmacology

OBJECTIVESTo investigate the effects of paclitaxel loaded ultrasound contrast agents on cell cycles and ultrastructural features of HepG2 cells.

METHODSHepG2 cells were cultured, and divided into a blank control group, a paclitaxel group, an ultrasound contrast agents group, and a paclitaxel loaded ultrasound contrast agents group. Cell cycles of the four groups were detected by flow cytometry, and the ultrastructural changes of the cells were observed under a transmission electron microscope.

RESULTSPaclitaxel loaded ultrasound contrast agents blocked the HepG2 cells at their G2/M phases, and it also induced more apoptosis of the HepG2 cells.

CONCLUSIONSPaclitaxel loaded ultrasound contrast agents can block HepG2 cells at the G2/M phase and induce apoptosis of the cells.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Contrast Media ; pharmacology ; Hep G2 Cells ; Humans ; Microscopy, Electron, Transmission ; Paclitaxel ; pharmacology

OBJECTIVETo investigate the impact of high-dose microbubbles induced by high mechanical index myocardial contrast echocardiography (MCE) on vascular permeability and its recovery time in rats.

METHODSThirty male Wistar rats were randomized into 4 MCE groups (groups A-D) and a control group. In the MCE groups, Evans blue was injected at 10 s before MCE (A), immediately after the end of MCE (B), and at 5 min (C) and 20 min after the end of MCE (D). In the control group, the microbubbles and Evans blue were injected at the end of a 5-min ultrasound exposure. All the rats were sacrificed 5 min after Evans blue injection, and the content of Evans blue in the myocardium and the percentage of Evans blue leakage area were determined.

RESULTSThe percentage of Evans blue leakage area in groups A, B and C were significantly higher than that in the control group (P<0.05), while the percentage was similar between group D and the control group (P>0.05). Evans blue contents in groups A and B were significantly higher than that in the control group (P<0.05), but groups C and D showed comparable contents with the control group E (P>0.05). No significant changes of the heart rates and premature beat number were observed during and after MCE in these groups (P>0.05).

CONCLUSIONHigh mechanical index MCE and a high contrast dose may induce increased microvascular leakage in rats, and the vascular permeability can recover in 20 min after MCE.

Animals ; Capillary Permeability ; drug effects ; Contrast Media ; pharmacology ; Coronary Vessels ; physiopathology ; Echocardiography ; Male ; Microbubbles ; Rats ; Rats, Wistar

Dendrimers are new macromolecules synthesized in recent years, which are of great interests in many fields where they have potential important applications because of their hyperbranched, well defined and monodisperse structures. In this paper, the unique structures, general synthesis routes and basic physical and chemical properties of dendrimers are introduced in brief, and the progress in the research of dendrimers in drug (gene) delivery, contrast agents, cancer therapy were reviewed, as well as the perspective in research and applications.
Contrast Media ; chemistry ; Dendrimers ; chemistry ; pharmacology ; Drug Carriers ; chemistry ; Drug Delivery Systems ; Gene Transfer Techniques ; Humans ; Polyamines

BACKGROUNDIt is of value to identify the non-invasive means that can accurately reflect the blood supply of epiphysis and is more sensitive in detection of early ischemia of epiphysis than the conventional gadoteridol (Gd)-enhanced SE T1WI. The aim of this study was to evaluate the blood supply of various anatomic regions at the end of normal growing long bone using dynamic Gd-enhanced MR imaging and compare the sensitivities between dynamic Gd-enhanced MR imaging and conventional Gd-enhanced SE T1WI in the detection of decreased blood perfusion of early epiphyseal ischemia.

METHODSTwenty-seven two-week-old piglets were used in this study. For the study of the end of normal growing long bone, unilateral MR imaging of the distal femur and proximal tibia was performed on eleven piglets. The comparison was made among various anatomic regions (physeal and epiphyseal cartilage, metaphyseal spongiosa, the secondary ossification center and metaphysis) using MRI in terms of the enhancement ratio and speed. Their relationships with the histological findings, including RBC/mm(2) and vessel distribution, were evaluated. To examine ischemic femoral head, 16 piglets were divided into two groups, with the control group having 8 piglets (involving 16 normal hips) and an ischemic group having 8 piglets (involving 16 hips with hyperabduction). In the ischemic group, MR imaging was performed on the hips in the hyperabduction immobilized persistently for 30 minutes. After MRI, the piglets were allowed to ambulate freely for 1 day and the same MR scanning was then repeated in a neutral position. The difference in enhancement ratio and speed of the femoral head between the control and ischemic group were evaluated.

RESULTSWith regard to the end of normal growing long bone, the enhancement ratio of the metaphyseal spongiosa was greatest among all the anatomic regions (P < 0.001). The enhancement ratio of physeal cartilage was greater than that of epiphyseal cartilage (P < 0. 001), which was the lowest in all tissues (P < 0.001). The enhancement speed of the spongiosa was greater than that of physis but the difference was not significant (P > 0.05). The enhancement speed of physis was greater than that of epiphyseal cartilage (P < 0.05), which was the lowest among all the tissues (P < 0.05). The enhancement ratio and speed were found to be related to the histological findings, including RBC/mm(2) (R > 0.75) and distribution of vessels in the tissues. With ischemic femoral head, the enhancement ratios of physis, anterior part and posterior part of capital femoral epiphysis were significantly lower (P < 0.05) and enhanced more slowly (P < 0.05) than those of normal femoral head on dynamic Gd-enhanced MR imaging. On conventional Gd-enhanced SE T1WI, however, no apparent decrease in enhancement ratio and speed in ischemic hips was found (P < 0.05), when they were compared with those in the normal hips.

CONCLUSIONSDynamic gadoteridol-enhanced MR imaging can reveal the blood supply in various anatomic regions of the end of normal growing long bone. It is more sensitive than conventional Gd-enhanced SE T1WI in the detection of early epiphyseal ischemia.

Animals ; Contrast Media ; pharmacology ; Epiphyses ; blood supply ; Femur ; blood supply ; Gadolinium ; Heterocyclic Compounds ; pharmacology ; Image Enhancement ; Magnetic Resonance Imaging ; methods ; Organometallic Compounds ; pharmacology ; Swine

OBJECTIVE: To evaluate transplanted porcine pancreatic islets in the kidney capsules of diabetic mice using a clinically approved superparamagnetic iron oxide (SPIO) and a 1.5T MR scanner. MATERIALS AND METHODS: Various numbers of porcine pancreatic islets labeled with Resovist, a carboxydextran-coated SPIO, were transplanted into the kidney capsules of normal mice and imaged with a 3D FIESTA sequence using a 1.5T clinical MR scanner. Labeled (n = 3) and unlabeled (n = 2) islets were transplanted into the kidney capsules of streptozotocin-induced diabetic mice. Blood glucose levels and MR signal intensities were monitored for 30 days post-transplantation. RESULTS: There were no significant differences in viability or insulin secretion between labeled and unlabeled islets. A strong correlation (r2 > 0.94) was evident between the number of transplanted islets and T2 relaxation times quantified by MRI. Transplantation with labeled or unlabeled islets helped restore normal sustained glucose levels in diabetic mice, and nephrectomies induced the recurrence of diabetes. The MR signal intensity of labeled pancreatic islets decreased by 80% over 30 days. CONCLUSION: The transplantation of SPIO-labeled porcine islets into the kidney capsule of diabetic mice allows to restore normal glucose levels, and these islets can be visualized and quantified using a 1.5T clinical MR scanner.
Animals ; Contrast Media/pharmacology ; Dextrans/pharmacology ; Diabetes Mellitus, Experimental/*therapy ; Glucose Tolerance Test ; *Islets of Langerhans Transplantation ; Magnetic Resonance Imaging/*methods ; Magnetite Nanoparticles ; Mice ; Microscopy, Electron ; Statistics, Nonparametric ; Swine

Eight Beagle dogs were anesthetized and were imaged using a single channel helical CT scanner. The contrast medium used in this study was iohexol (300 mg I/ml) and doses were 0.5 ml/kg for a cine scan, 3 ml/kg for an enhanced scan. The flow rate for contrast material administration was 2 ml/sec for all scans. This study was divided into three steps, with unenhanced, cine and enhanced scans. The enhanced scan was subdivided into the arterial phase and the venous phase. All of the enhanced scans were reconstructed in 1 mm intervals and the scans were interpreted by the use of reformatted images, a cross sectional histogram, maximum intensity projection and shaded surface display. For the cine scans, optimal times were a 9-sec delay time post IV injection in the arterial phase, and an 18-sec delay time post IV injection in the venous phase. A nine-sec delay time was acceptable for the imaging of the canine hepatic arteries by CT angiography. After completion of arterial phase scanning, venous structures of the liver were well visualized as seen on the venous phase.
Angiography/methods/*veterinary ; Animals ; Contrast Media/pharmacology ; Dogs/*anatomy & histology ; Iohexol/pharmacology ; Liver/*blood supply ; Tomography, X-Ray Computed/methods/*veterinary

OBJECTIVETo investigate the magnetic resonance (MR) signal features of superparamagnetic iron oxide (SPIO) with different particle size and concentration.

METHODSThe superparamagnetic iron oxide with different concentration and particle size was scanned by magnetic resonance; T1, T2 and T2(*) values of each group were recorded to evaluate the features of MR signals.

RESULTSThe T1 value of SPIO with different particle size had negative linear relationship with concentration. In low concentration the T2 and T2(*) values were elevated markedly with the particle size decreased; while in high concentration the T2 and T2(*)values were elevated gently with particle size decreased. lg(T2), particle size and concentration of SPIO had linear relationship.

CONCLUSIONSSPIO affects magnetic resonance signal mainly with effect on T1 and T2. T2 value can be regarded as the major detection index in the magnetic resonance scan of SPIO. There is a linear relationship among particle size, SPIO concentration and lg(T2) value.

Contrast Media ; pharmacology ; Dose-Response Relationship, Drug ; Ferrosoferric Oxide ; chemistry ; pharmacology ; Humans ; Image Enhancement ; Magnetic Resonance Imaging ; methods ; Magnetite Nanoparticles ; chemistry ; Particle Size

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

Computed tomographic arthrography (CTA) of four cadaveric canine stifles was performed before and after partial cranial cruciate ligament rupture in order to verify the usefulness of CTA examination for the diagnosis of partial cranial cruciate ligament rupture. To obtain the sequential true transverse image of a cranial cruciate ligament, the computed tomography gantry was angled such that the scanning plane was parallel to the fibula. True transverse images of cranial cruciate ligaments were identified on every sequential image, beginning just proximal to the origin of the cranial cruciate ligament distal to the tibial attachment, after the administration of iodinated contrast medium. A significant decrease in the area of the cranial cruciate ligament was identified on CTA imaging after partial surgical rupture of the cranial cruciate ligament. This finding implies that CTA can be used for assessing partial cranial cruciate ligament ruptures in dogs.
Animals ; Anterior Cruciate Ligament/*injuries/*radiography ; Arthrography/methods/veterinary ; Contrast Media/*pharmacology ; Dog Diseases/*radiography ; Dogs ; Hindlimb ; Predictive Value of Tests ; Stifle/radiography ; Tomography, X-Ray Computed/methods/*veterinary