OBJECTIVE. Our purpose wasto evaluate therelationships betweentheratioof maxi mum relative cerebral blood volume (rCBV) (rCBV ratio = rCBV[tumor] I rCBV[contralat eral white matter]) and histologic and angiographic vascularities of gliomas using the gradient-echo echoplanar MR imaging technique. We also evaluated the usefulness of rCBV maps for grading gliomas. SUBJECTS AND METHODS. We examined 30 patients with histologically verifiedgliomas. Gliomas were classified as glioblastoma, anaplastic glioma with enhancement, ana plastic glioma without enhancement, and low-grade glioma. The maximum rCBV ratio of each glioma was compared with both histologic and angiographic vascularities, and the rela tionship between the maximum rCBV ratios and each type of glioma was established. RESULTS. The maximumrCBV ratiosof thegliomassignificantly correlated with both for low-gradegliomas.The maximumrCBV ratiosofthe glioblastomaswere significantlyhigher than those of the anaplastic gliomas without enhancement (p = .002) and the low-grade gliomas (p < .001). The maximum rCBV ratios of the anaplastic gliomas with enhancement were higher than those of the anaplastic gliomas without enhancement and the low-grade glio mas, but the differences were not statistically significant (p = .08 and p = .03, respectively). CONCLUSION. The resultsof perfusion-sensitive MR imagingwith gradient-echoechoplanar technique correlated with both histologic and angiographic vascularities. [6] reportedthat the degree of vascularity of gliomas observed with a spin echo echoplanar technique correlated well with histologic vascularity and that these re suIts might show the ability of the spin-echo echoplanar technique to detect neovasculariza tion at the capillary level. However, tumor an giogenesis is a complex process, and the existence of larger neovascular structures (such as feeding arteries and draining veins) associated with malignant tumors is not un common. A study documented that some tu mors have average capillary diameters two to three times those of normal tissues [7].The gradient-echo echoplanar technique produces hemodynamic maps by representing theeffectsoftotal bloodvolumefromcapillar ies to large vessels and weighs all vessels ape proximately equally [8]. In addition, this technique, because of its greater sensitivity to

Developments in MRI have made it possible to use diffusion-weighted MRI, perfusion MRI and proton MR spectroscopy (MRS) to study lesions in the brain. We evaluated whether these techniques provide useful, complementary information for grading gliomas, in comparison with conventional MRI. We studied 17 patients with histologically verified gliomas, adding multivoxel proton MRS, echoplanar diffusion and perfusion MRI the a routine MRI examination. The maximum relative cerebral blood volume (CBV), minimum apparent diffusion coefficient (ADC) and metabolic peak area ratios in proton MRS were calculated in solid parts of tumours on the same slice from each imaging data set. The mean minimum ADC of the 13 high-grade gliomas (0.92+/-0.27 x 10(-3) mm(2)/s) was lower than that of the four low-grade gliomas (1.28+/-0.15 x 10(-3) mm(2)/s) ( P<0.05). Means of maximum choline (Cho)/N-acetylaspartate (NAA), Cho/creatine (Cr), Cho/Cr in normal brain (Cr-n) and minimum NAA/Cr ratios were 5.90+/-2.62, 4.73+/-2.22, 2.66+/-0.68 and 0.40+/-0.06, respectively, in the high-grade gliomas, and 1.65+/-1.37, 1.84+/-1.20, 1.61+/-1.29 and 1.65+/-1.61, respectively, in the low-grade gliomas. Significant differences were found on spectroscopy between the high- and low-grade gliomas ( P<0.05). Mean maximum relative CBV in the high-grade gliomas (6.10+/-3.98) was higher than in the low-grade gliomas (1.74+/-0.57) ( P<0.05). Echoplanar diffusion, perfusion MRI and multivoxel proton MRS can offer diagnostic information, not available with conventional MRI, in the assessment of glioma grade.

Urea cycle disorders (UCDs) are one of the most frequently inherited metabolic diseases in Japan, with an estimated prevalence of 1 per 50,000 live births. Here, we investigated the clinical manifestations, treatment, and prognosis of 177 patients with UCDs who were evaluated and treated from January 1999 to March 2009. These included 77 cases of neonatal-onset UCDs and 91 cases of late-onset UCDs. The most common UCD was ornithine transcarbamylase deficiency (OTCD), which accounted for 116 out of 177 patients. This result is similar to a previous study performed between 1978 and 1995 in Japan: OTCD accounted for about two-thirds of the total number of UCD cases. We studied the relationship between prognosis and the peak blood ammonia level at the onset in 151 UCD patients. Compared with a previous survey conducted in Japan, we found that a greater number of patients survived without any mental retardation despite their peak blood ammonia levels being greater than 360 μmol/l. The 5-year survival rate of patients with OTCD improved to 86% for those with the neonatal-onset type and to 92% for those with the late-onset type. We hypothesize that the increased survival rate is due to early diagnosis and better treatments that are now available in Japan. It is very important to diagnose and treat UCDs, especially OTCD, when the blood ammonia levels in patients are low. The outcome in patients with low blood ammonia levels was better than that in patients with high blood ammonia levels.

Our aim was to review the MRI appearances of primary intracranial germ-cell tumours (GCT). We reviewed the MRI studies of 32 patients: 19 with germinomas, five with teratomas, one with an embryonal carcinoma, five with mixed and two with malignant nongerminomatous GCT. Eleven were in the pineal region, 12 suprasellar, five in the both sites, two in the basal ganglia and two in the corpus callosum. Contrast-enhanced images were available for 27 patients. The solid parts of GCT were nearly isointense with grey matter on both T1- and T2-weighted images. In seven patients with nongerminomatous GCT high-signal components were found on T1-weighted images, representing haemorrhage, high-protein fluid or fat. Cystic components were detected in 17 of 27 patients; eight germinomas and all nine nongerminomatous GCT had cysts. The solid components of germinomas enhanced homogeneously in eight cases and heterogeneously in 10, while all nongerminomatous GCT showed heterogeneous enhancement. MRI features tumours can facilitate correct diagnosis of GCT, including histological subtypes.

BACKGROUND AND PURPOSE:The usefulness of contrast-enhanced 3D T2-FLAIR MR imaging for the evaluation of leptomeningeal diseases has not been systematically investigated. The purpose of this study was to assess the value added by contrast-enhanced 3D T2-FLAIR and MPRAGE sequences to conventional postcontrast T1-weighted images in the evaluation of leptomeningeal diseases. We also undertook in vitro studies in attempts to understand the consequences of our patient study.

Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency and mitochondrial acetoacetyl-CoA thiolase (betaketothiolase or

No abstract

[Arg8]Vasopressin (AVP) has an antilipolytic action on adipocytes, but little is known about the mechanisms involved. Here, we examined the involvement of the V1a receptor in the antilipolytic effect of AVP using V1a receptor-deficient (V1aR-/-) mice. The levels of blood glycerol were increased in V1aR-/- mice. The levels of ketone bodies, such as acetoacetic acid and 3-hydroxybutyric acid, the products of the lipid metabolism, were increased in V1aR-/- mice under a fasting condition. Triacylglyceride and free fatty acid levels in blood were decreased in V1aR-/- mice. Furthermore, measurements with tandem mass spectrometry determined that carnitine and acylcarnitines in serum, the products of beta-oxidation, were increased in V1aR-/- mice. Most acylcarnitines were increased in V1aR-/- mice, especially in the case of 2-carbon (C2), C10:1, C10, C14:1, C16, C18:1, and hydroxy-18:1-carbon (OH-C18:1)-acylcarnitines under feeding rather than under fasting conditions. The analysis of tissue C2-acylcarnitine level showed that beta-oxidation was promoted in muscle under the feeding condition and in liver under the fasting condition. An in vitro assay using brown adipocytes showed that the cells of V1aR-/- mice were more sensitive to isoproterenol for lipolysis. These results suggest that the lipid metabolism is enhanced in V1aR-/- mice. The cAMP level was enhanced in V1aR-/- mice in response to isoproterenol. The phosphorylation of Akt by insulin stimulation was reduced in V1aR-/- mice. These results suggest that insulin signaling is suppressed in V1aR-/- mice. In addition, the total bile acid, taurine, and cholesterol levels in blood were increased, and an enlargement of the cholecyst was observed in V1aR-/- mice. These results indicated that the production of bile acid was enhanced by the increased level of cholesterol and taurine. Therefore, these results indicated that AVP could modulate the lipid metabolism by the antilipolytic action and the synthesis of bile acid via the V1a receptor.