Confirmation of Age-dependence in the Leakage of Contrast Medium around the Cortical Veins into Cerebrospinal Fluid after Intravenous Administration of Gadolinium-based Contrast Agent

Purpose:It has been reported previously that intravenously administered gadolinium-based contrast agent (GBCA) leaks into the subarachnoid space around the cortical veins at 4 h after injection in all old people over 37 years, but not in younger people up to 37 years of age in 3D-real IR images. The purpose of this study was to investigate whether there was a strict threshold of 37 years of age for the leakage of the GBCA into the subarachnoid space.Methods:The subjects included 190 patients, that were scanned for 3D-real IR images at 4 hours after intravenous injection of GBCA as a diagnostic test for endolymphatic hydrops. The patient’s age ranged from 14 to 81 years. Two experienced neuroradiologists evaluated the images to determine whether the GBCA leakage around the cortical veins was positive or negative. Any discrepancies between the two observers were discussed and a consensus was obtained.A Mann–Whitney U test and receiver operating characteristic (ROC) curve analysis were used to compare the positive and the negative group and to set the age cut-off value for the prediction of GBCA leakage.Results:The GBCA leakage around the cortical veins was negative in 35 patients and positive in 155 patients. The average age was 33 ± 11 years in the negative group, and 55 ± 12 years in the positive group (P < 0.01). In the ROC analysis for the age and leakage of the GBCA, an area under the curve was 0.905 and the cut-off age was 37.317 years (sensitivity of 0.942 and specificity of 0.771).Conclusion:Intravenously administered GBCA leaks into the subarachnoid space around the cortical veins in most patients over 37 years of age. However, it should be noted that it can be found occasionally in patients under 37 years of age.     

Severe Graves' ophthalmopathy accompanied by myasthenia gravis]

We report a 53-year-old woman with severe Graves' ophthalmopathy accompanied by uncontrolled myasthenia gravis. She presented remarkable exophthalmos, chemosis, and restriction of eye movement. Despite plasma exchange, steroid pulse therapy, local injection of steroid, and irradiation, ocular symptoms did not ameliorate. Since optic neuropathy was seen, orbital decompression surgery was performed in the left eye. Bilateral chemosis was improved after the surgery. Five years after surgery, there was no ocular palsy in the operated left eye, but in the contralateral eye. For the good prognosis of the eye movement, orbital decompression might be recommended in the severe Graves' ophthalmopathy accompanied by the optic neuropathy and/or ophthalmoplegia with proptosis.     

5-HT(2) receptor-mediated phosphoinositide hydrolysis in bovine ciliary epithelium.

The serotonin 2 (5-HT(2)) receptor antagonists, MCI-9042 (Anplag) and ketanserin, have been shown to lower intraocular pressure in rabbits (1) and humans (2). The mechanism of action of these drugs has not been determined, but it is hypothesized that 5-HT(2) receptors, and possibly alpha-adrenergic receptors, (3) may regulate in part aqueous humor production via an intracellular signal transduction pathway in the ciliary body. We therefore examined whether 5-HT(2) receptors were coupled to phosphoinositide hydrolysis in an organ culture system of isolated bovine ciliary epithelium. 5-HT stimulated [(3)H]inositol phosphates ([(3)H]InsPs) accumulation in a dose-dependent manner with a maximum increase approximately twice over the basal level. The mean EC(50) value was 1.1 microM, which was calculated from four dose-response curves. The 5-HT stimulated accumulation of [(3)H]InsPs was inhibited by spiperone (5-HT(2A/1A) and dopamine 2 (D(2)) antagonists), M-1 (a major metabolite of MCI-9042), ketanserin (5-HT(2A) antagonist), SB-206553 (5- HT(2B/2C) antagonist), and mesulergine (5-HT(2C) antagonist and D(2) agonist). It was not inhibited by chlorpromazine, which is a D(2) receptor antagonist. Accordingly, our study demonstrates that 5-HT(2) receptors are coupled to phospholipase C in bovine ciliary epithelium.     

Levels and ages of selenium and metals in sedimentary cores of Ise Bay as determined by 210-Pb dating technique

Bulletin of Environmental Contamination and Toxicology -     

Characterization of peptide components in the venom of the scorpion Liocheles australasiae (Hemiscorpiidae).

Scorpion venoms are composed of a number of neurotoxic peptides. A variety of toxins have been isolated from the venoms of scorpions of the family Buthidae, however, little interest has been paid to non-Buthidae scorpions. In this study, we examined the toxicity of the venom of Liocheles australasiae (Hemiscorpiidae) to mice and crickets, and characterized the peptide components by HPLC and mass spectrometry. Over 200 components were detected in the L. australasiae venom by LC/MS analysis, with components of molecular masses ranging from 500 to 5000 Da being particularly abundant. A number of peptides contained two to four disulfide bridges, which was estimated based on the mass difference after derivatization of Cys residues. A peptide having a monoisotopic molecular mass of 7781.6 Da and four disulfide bridges was isolated from the venom. The peptide has a primary structure similar in terms of the position of eight Cys residues to those observed in several peptides found from scorpions, ticks and insects, although biological roles of these peptides are unknown.