BACKGROUND: We evaluated the effects of endurance exercise and a high-fat diet on insulin resistance and ceramide contents of skeletal muscle in Sprague-Dawley rats. METHODS: We randomly divided 32 rats into four groups: control (CON, n = 8), high fat diet (HF, n = 8), exercise (Ex, 24 m/min for 2 hours, 5 days/wk, n = 8), HF/Ex (n = 8). After 4-week treatments, plasma lipid profiles, glucose and insulin concentrations were measured. The triglycerides (TG), ceramide, and glucose transporter 4 (GLUT-4) contents were measured in the skeletal muscle. The rate of glucose transport was determined under submaximal insulin concentration during the muscle incubation. RESULTS: Free fatty acid levels were significantly higher in CON and HF than Ex (P = 0.032). Plasma glucose levels in HF were significantly higher than the two Ex groups (P = 0.002), and insulin levels were significantly higher in HF than in other three groups (P = 0.021). Muscular TG concentrations were significantly higher in HF than CON and Ex and also in HF/Ex than Ex, respectively (P = 0.005). Hepatic TG concentrations were significantly higher in HF than other three groups but Ex was significantly lower than HF/Ex (P = 0.000). Muscular ceramide content in HF was significantly greater than that in either Ex or HF/Ex (P = 0.031). GLUT-4 levels in CON and HF were significantly lower than those in Ex and HF/Ex (P = 0.009, P = 0.003). The glucose transport rate in submaximal insulin concentration was lower in CON than in either Ex or HF/Ex (P = 0.043), but not different from HF. CONCLUSION: This study suggests that high fat diet for 4 weeks selectively impairs insulin resistance, but not glucose transport rate, GLUT-4 and ceramide content in skeletal muscle per se. However, endurance exercise markedly affects the content of ceramide and insulin resistance in muscle.
Animals ; Ceramides ; Diet, High-Fat ; Glucose ; Glucose Transport Proteins, Facilitative ; Glucose Transporter Type 4 ; Insulin ; Insulin Resistance ; Muscle, Skeletal ; Muscles ; Plasma ; Rats ; Rats, Sprague-Dawley ; Triglycerides

PURPOSE: To demonstrate a CT technique by which carcinoma of the ampulla of Vater can be more accurately diagnosed, and to describe the radiologic findings this carcinoma. MATERIALS AND METHODS: We retrospectively reviewed CT findings in 26 patients with pathologically proven carcinoma of the ampulla of Vater. One additional cup of diluted oral contrast medium was ingested immediately before the scan. We analysed the difference in detection rate of the mass in the duodenal lumen with and without duodenal luminal opacification of gastrografin.We also evaluated the size and shape of the mass, dilatation of CBD and the pancreatic duct, and lymph node metastasis. In addition, we analyzed multimodality imaging findings ultrasonogram (US) : 13; hypotonic duodenogram (HTDG): 7; ERCP : 17) of carcinoma of the ampulla of Vater. RESULTS: Nodular soft tissue masses protruding into the duodenal lumen were identified in 21 of 26 cases. In 95% of cases (21/22) with favorable opacification and distension of the duodenum, masses were clearly identified on CT imaging. However, in four caseswith poor opacification and distension of the duodenum, masses could not be observed(P=0.000). The mass on CT scanshowed a well-defined margin, round or lobulated contour, and contrast enhancement similar to that of thepancreas. CBD dilatation was identified in 20 cases and pancreatic duct dilatation in 12. On US, protruding massesin the distal CBD were observed in nine of 13 cases(60%) and on HTDG, in six of seven cases(86%). as well-definedfilling defects. Conclusion : Since the accuracy of CT diagnosis of intestinal lesions is directly proportional tothe degree of intestinal distension and opacification with oral contrast, we believe that adequate ct techniquefor distending and opacitying the duodeual lumen are necessary for early diagnosis of carcinoma of the ampulla ofVater.
Ampulla of Vater* ; Cholangiopancreatography, Endoscopic Retrograde ; Diagnosis ; Dilatation ; Duodenum ; Early Diagnosis ; Humans ; Lymph Nodes ; Neoplasm Metastasis ; Pancreatic Ducts ; Phenobarbital ; Retrospective Studies ; Ultrasonography

PURPOSE: To retrospectively evaluate the usefulness of diffusion-weighted images, ADC maps and conventional MR images for determination of brain tumor consistency. MATERIALS AND METHODS: Twenty-three patients with brain tumor underwent MR examinations with T1, T2 and diffusion-weighted images. Regions of interest (ROIs) were drawn in the tumors, and the measured signal intensities (SI) were normalized with the contralateral side. We evaluated the correlation between SI ratios from various images and tumor consistency assessed at surgery. In three patients with both cystic and solid components, each component was evaluated independently. Qualitatively observed SIs were also correlated with tumor consistency. RESULTS: Statistical analysis revealed significant correlation between tumor consistency and ADC ratio (r = -0.586, p = 0.002), SI ratios on T2-weighted images (r = -0.497, p = 0.010), and observed SIs on T2-weighted images (r = -0.461, p = 0.018). The relative ratio of ADC value correlated with tumor consistency most strongly. CONCLUSION: The measured ratio of ADC, SI ratio and observed SI grade on T2-weighted images can provide valuable information about the consistency of brain tumor.
Brain ; Brain Neoplasms ; Humans ; Retrospective Studies

PURPOSE: To compare the arterial and venous detection sites of triggering methods in contrast-enhanced-MR-venography (CE-MRV) for the evaluation of intracranial venous system. MATERIALS AND METHODS: 41 healthy patients underwent CE-MRV with autotriggering at either the cavernous segment of internal carotid artery with an inserted time-delay of 6 seconds (n = 20) or the superior sagittal sinus without any time-delay (n = 21). 0.1 mmol/kg gadolinium-based contrast material (Magnevist(R), Schering, Germany) was intravenously injected by hand injection. A sagittal fast-spoiled-gradient-echo-sequence ranging from one ear to the other was performed (TR/TE5.2/1.5, Matrix 310x310, 124 sections in the 15-cm-thick volume). 17 predefined venous structures were evaluated on all venograms by two neuroradiologists and defined as completely visible, partially visible, or none visible. RESULTS: The rate of completely visible structures were 272 out of 323 (84%) in the arterial triggering CE-MRV and 310 out of 340 (91%) in the venous triggering CE-MRV. The venous triggering CE-MRV demonstrated an overall superior visualization of the cerebral veins than the arterial triggering CE-MRV (Fisher exact test, p < 0.006). CONCLUSION: CE-MRV using venous autotriggering method provides higher-quality images of the intracranial venous structures compared to that of arterial.
Carotid Artery, Internal ; Caves ; Cerebral Veins ; Ear ; Hand ; Humans ; Superior Sagittal Sinus

Arachnoid cyst of the cavernous sinus is very rare. When present, its anatomic location frequently gives rise to cranial nerve palsy. We report a case of arachnoid cyst of the cavernous sinus in a 38-year-old man with impaired eyeball movement and diplopia.
Adult ; Arachnoid Cysts ; Arachnoid* ; Cavernous Sinus* ; Cranial Nerve Diseases ; Diplopia ; Humans

PURPOSE: To describe the imaging findings at susceptibility weighted imaging (SWI) at 3T in patients with occlusion of middle cerebral artery, and to correlate the absence or presence of arterial bright foci in sylvian fissure, as one of their finding at SWI, with the diffusion weighted imaging (DWI) scores. MATERIALS AND METHODS: We included 12 patients with symptomatic unilateral occlusion of middle cerebral artery. Retrospective review of SWI and DWI was done. On DWI, size of infarction was analyzed according to the ASPECTS grading system. On SWI, presence of hemorrhage, dark blooming of intravascular clot, distension of medullary or cortical vein, and absence or presence of bright arterial foci in sylvian fissure were evaluated. RESULTS: Of 12 patients with symptomatic unilateral MCA occlusion, SWI showed dark blooming of intravascular clot in 8 patients (66.7%), distended medullary or cortical vein in 7 patients (58.3%), nonvisualization of arterial bright signal intensity in sylvian fissure in 7 patients (58.3%), and hemorrhage in one patient (8.3%). In comparison with DWI, patients with sylvian arterial bright signal intensity showed better ASPECTS score (6.4+/-4.1) than patients without arterial bright signal intensity (4.4+/-1.1), yet it was not statistically significant (p=0.267, t-test). CONCLUSION: SWI at 3T provides added diagnostic information including site of occlusion, collateral flow by arterial bright signal intensity in sylvian fissure and early hemorrhagic transformation in patients with symptomatic MCA occlusion.
Diffusion ; Hemorrhage ; Humans ; Infarction ; Infarction, Middle Cerebral Artery ; Middle Cerebral Artery ; Retrospective Studies ; Stroke ; Veins

It has been recognized that ginseng has anti-diabetic effects in skeletal muscle, but the mechanism has not been intensively investigated. The aim of this study was to investigate the effects of Korean red ginseng (Panax ginseng) supplementation on muscle glucose uptake in high-fat fed rats. Sixteen rats were randomly divided into two groups: a control group (CON, n = 8) and a Korean red ginseng group (KRG, n = 8). The KRG group ingested RG extract (1 g·kg(-1), 6 days/week) mixed in water for two weeks. After the two-week treatment, plasma lipid profiles, and glucose and insulin concentrations were measured. The triglyceride (TG) and glucose transporter 4 (GLUT-4) contents were measured in the skeletal muscle and liver. The rate of glucose transport was determined under a submaximal insulin concentration during muscle incubation. Plasma FFA concentrations were significantly decreased in KRG (P < 0.05). Liver and muscle triglyceride concentrations were also decreased in the KRG treatment group (P < 0.05) compared to the CON group. In addition, resting plasma insulin and glucose levels were significantly lower after Korean red ginseng treatment (P < 0.05). However, muscle glucose uptake was not affected by Korean red ginseng treatment, as evidenced by the rate of glucose transport in the epitorchealis muscle under submaximal insulin concentrations. These results suggest that while KRG supplementation could improve whole body insulin resistance and plasma lipid profiles, it is unlikely to have an effect on the insulin resistance of skeletal muscle, which is the major tissue responsible for plasma glucose handling.
Animals ; Diabetes Mellitus, Type 2 ; drug therapy ; metabolism ; Diet, High-Fat ; adverse effects ; Dietary Fats ; adverse effects ; Dietary Supplements ; analysis ; Glucose ; metabolism ; Glucose Transporter Type 4 ; metabolism ; Humans ; Hypoglycemic Agents ; administration & dosage ; Male ; Muscle, Skeletal ; drug effects ; metabolism ; Panax ; chemistry ; Phytotherapy ; Plant Extracts ; administration & dosage ; Rats ; Triglycerides ; metabolism

PURPOSE: Effect of recombinant human growth hormone (rhGH) administration on lipid storage, and its subsequent effect on insulin sensitivity have not yet been adequately examined. Thus, we investigated the effects of rhGH treatment on muscle triglyceride (TG) and ceramide content, and insulin sensitivity after 4 weeks of rhGH administration in rats. MATERIALS AND METHODS: Fourteen rats were randomly assigned to two groups: rhGH injection group (GH, n = 7) and saline injection group (CON, n = 7). GH received rhGH by subcutaneous injections (130microgram/kg(-1)/day(-1), 6 days/week(-1)) for 4 weeks, while CON received saline injections that were equivalent in volume to GH group. Intramuscular TG and ceramide content and hepatic TG content were measured. To determine insulin sesitivity, oral glucose tolerance test (OGTT) and muscle incubation for glucose transport rate were performed in rats, and used as indicators of insulin sensitivity. We also examined plasm lipid profiles. RESULTS: After 4 weeks of rhGH treatment, the GH group had higher muscle and liver TG contents than the CON (p < 0.05). Ceramide content in GH was significantly greater than that in CON (p < 0.05). GH also had higher plasma levels of FFA (p < 0.05), glucose and insulin responses during OGTT (p < 0.05), and lower glucose transport rates in submaximal insulin concentration (p < 0.05) as compared with CON. Results indicate that rhGH treatment is associated with insulin resistance in rats. CONCLUSION: rhGH treatment elevated muscle TG and ceramide content, and hepatic TG content. Thus, elevation of these compounde by rhGH treatment could contribute to the development of insulin resistance in rats.
Animals ; Ceramides/metabolism ; Glucose/metabolism ; Glucose Transporter Type 4/metabolism ; Human Growth Hormone/*administration & dosage ; Humans ; *Insulin Resistance ; Male ; Muscle, Skeletal/*drug effects/*metabolism ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins/administration & dosage ; Triglycerides/metabolism

PURPOSE: A relative increase in deoxyhemoglobin levels in hypoperfused tissue can cause prominent hypointense signals in the draining veins (PHSV) within areas of impaired perfusion in susceptibility-weighted imaging (SWI). The purpose of this study is to evaluate the usefulness of SWI in patients with acute cerebral infarction by evaluating PHSV within areas of impaired perfusion and to investigate the usefulness of PHSV in predicting prognosis of cerebral infarction. MATERIALS AND METHODS: In 18 patients with acute cerebral infarction who underwent brain MRI with diffusion-weighted imaging and SWI and follow-up brain MRI or CT, we reviewed the presence and location of the PHSV within and adjacent to areas of cerebral infarction qualitatively and measured the signal intensity difference ratio of PHSVs to contralateral normal appearing cortical veins quantitatively on SWI. The relationship between the presence of the PHSV and the change in the extent of infarction in follow-up images was analyzed. RESULTS: Of the 18 patients, 10 patients showed progression of the infarction, and 8 patients showed little change on follow-up imaging. On SWI, of the 10 patients with progression 9 patients showed peripheral PHSV and the newly developed infarctions corresponded well to area with peripheral PHSV on initial SWI. Only one patient without peripheral PHSV showed progression of the infarct. The patients with infarction progression revealed significantly higher presence of peripheral PHSV (p=0.0001) and higher mean signal intensity difference ratio (p=0.006) comparing to the patients with little change. CONCLUSION: SWI can demonstrate a peripheral PHSV as a marker of penumbra and with this finding we can predict the prognosis of acute infarction. The signal intensity difference of PHSV to brain tissue on SWI can be used in predicting prognosis of acute cerebral infarction.
Brain ; Cerebral Infarction ; Follow-Up Studies ; Humans ; Infarction ; Magnetic Resonance Imaging ; Perfusion ; Prognosis* ; Veins*

OBJECTIVE: Intracranial stenting for stent-assisted coiling of aneurysms requires adequate follow-up imaging. The aim of this in vitro study was to compare in-stent artificial luminal narrowing on contrast-enhanced MR angiograms (CE-MRA) when applying Neuroform(R) and Enterprise(R) stents for stent-assisted coiling. MATERIALS AND METHODS: Two intracranial nitinol stents (Enterprise(R) and Neuroform(R)) were placed in silicon tubes and then imaged at 3 T and 1.5 T by the use of a T1-weighted three-dimensional spoiled gradient-echo sequence with minimal TR and TE. CE-MRAs were obtained by using different imaging planes, voxel sizes, and bandwidths, and with or without parallel imaging. Artificial lumen narrowing (ALN) was calculated and the results were compared. RESULTS: Lower magnetic field strength, axial plane perpendicular to axis of stent, and wider bandwidth resulted in a lower ALN on CE-MRA for both stents. Larger voxel size resulted in lower ALN for Neuroform(R) stent. The parallel imaging acceleration factor did not affect ALN. The mean ALN was lower for Neuroform(R), but it was not significant by a paired t test. CONCLUSION: CE-MRA of the stented lumen of vascular phantom was partially impaired with ALN. Consequently, image plane orientation, magnetic field strength, bandwidth, and voxel size should be adjusted appropriately to reduce ALN.
Alloys ; Cerebral Angiography ; Contrast Media/diagnostic use ; Humans ; Imaging, Three-Dimensional ; Intracranial Aneurysm/*pathology/*therapy ; Linear Models ; Magnetic Resonance Angiography/*methods ; Phantoms, Imaging ; Reproducibility of Results ; *Stents