An experimental approach to study the biosynthesis of brominated metabolites by the red algal genus Laurencia.

The production of labeled brominated metabolites with radioactive (82)Br in Laurencia species was investigated as part of a study of the biosynthesis of halogenated metabolites from species belonging to the red algal genus Laurencia (Rhodomelaceae, Ceramiales). Radiobromide [(82)Br], thin-layer chromatography (TLC), and TLC-autoradioluminography (ARLG) were used. When cultured in artificial seawater medium (ASP(12)NTA including Na(82)Br) under 16:8 h light:dark (LD) illumination cycles for 24 h, each of the strains of Laurencia, Laurencia japonensis Abe et Masuda, Laurencia nipponica Yamada (laurencin-producing race and laureatin-producing race), and Laurencia okamurae Yamada, produced species- (or race-) specific (82)Br-containing metabolites. In the case of the laurencin-producing race of L. nipponica, laurencin and deacetyllaurencin were found to be produced in approximately 1:1 ratio, though laurencin is the major metabolite in the wild sample. Furthermore, when cultured in the dark, the production rates of brominated metabolites in Laurencia spp. were found to be diminished. The present study strongly indicates that the use of radiobromine [(82)Br] in combination with the TLC-ARLG method is an effective approach for investigating the biosynthesis of brominated metabolites in Laurencia.

Preoperative identification of subthalamic nucleus for deep brain stimulation using three-dimensional phase sensitive inversion recovery technique.

PURPOSE: We assessed the feasibility of utilizing three-dimensional (3D) phase sensitive inversion recovery (IR) images for preoperatively determining deep brain stimulator position. METHODS: We measured geometric distortion with a grid phantom and evaluated images of 3 volunteers to determine optimum imaging parameters for 3D phase sensitive IR. RESULTS: Geometric distortion measured less than 1.0%. Respective inversion and recovery times, which provided high T(1) contrast between the subthalamic nucleus and adjacent tissue, were 200 and 4000 ms. In studies of 3 volunteers and 2 patients, the subthalamic nucleus was clearly depicted in 3D phase sensitive IR images. The measured coordinates of the subthalamic nucleus agreed well with those calculated by conventional estimation from midpoint of the anterior and posterior commissure. CONCLUSION: Three-dimensional phase sensitive inversion recovery was useful in visualizing the subthalamic nucleus for effective deep brain stimulation.

Preoperative assessment of the aberrant bile duct using multislice computed tomography cholangiography.

BACKGROUND: This study aimed to determine the frequency of anatomic variations of bile ducts (aberrant bile ducts) using multislice helical computed tomography (MCT) cholangiography. METHODS: MCT scanning was performed after slow infusion of 100 mL meglumine iotroxate. Overlapping axial images, taken at 0.5-mm intervals, were reconstructed to create a multiplanar reconstruction with volume rendering. We analyzed anatomical variations of the biliary tree by MCT cholangiography. RESULTS: In a total of 113 patients, MCT cholangiography provided clear images of aberrant bile ducts in 18 patients. Major type (draining a particular segment of the liver) was found in 9 cases (8%) and minor type (draining a particular subsegment of the liver) in 9 cases (8%). CONCLUSIONS: Preoperative MCT cholangiography provides important information about the precise biliary anatomy and can reveal unexpected aberrant bile ducts prior to biliary surgery, especially laparoscopic cholecystectomy.

A case of metastatic pulmonary calcification after transient acute renal failure.

We report a case of metastatic pulmonary calcification that appeared on high-resolution CT (HRCT) as multiple, lobular, ground-glass opacities sparing the perilobular area. Diffuse metastatic calcification such as that in our case was considered to be a result of postoperative transient acute renal failure. Decreasing alveolar air spaces due to both alveolar septal fibrosis and calcification caused the diffuse ground-glass opacities in the present case.

Virtual endoscopic images by 3D FASE cisternography for neurovascular compression.

Three-dimensional fast asymmetric spin echo (3D FASE) cisternography provides high spatial resolution and excellent contrast as a water image acquisition technique. It is also useful for the evaluation of various anatomical regions. This study investigated the usefulness and limitations of virtual endoscopic images obtained by 3D FASE MR cisternography in the preoperative evaluation of patients with neurovascular compression. The study included 12 patients with neurovascular compression: 10 with hemifacial spasm and two with trigeminal neuralgia. The diagnosis was surgically confirmed in all patients. The virtual endoscopic images obtained were judged to be of acceptable quality for interpretation in all cases. The areas of compression identified in preoperative diagnosis with virtual endoscopic images showed good agreement with those observed from surgery, except in one case in which the common trunk of the anterior inferior cerebellar artery and posterior inferior cerebellar artery (AICA-PICA) bifurcated near the root exit zone of the facial nerve. The veins are displayed in some cases but not in others. The main advantage of generating virtual endoscopic images is that such images can be used for surgical simulation, allowing the neurosurgeon to perform surgical procedures with greater confidence.

Brominated labdane-type diterpenoids from an Okinawan Laurencia sp.

From an unidentified species of Laurencia collected from Okinawan waters two novel brominated metabolites, 1 and 2, along with known halogenated compounds, 2,10-dibromo-3-chloro-alpha-chamigrene (3) and microcladallene A (4), were isolated and identified. The structures of these new compounds were established as ent-labdane-type bromoditerpenes, (1S,3R,5S,6S,8S,9S,10R,13R)-1-acetoxy-3-bromo-6-hydroxy-8,13-epoxy-labd-14-ene (1) and (3R,5S,6S,8S,9S,10R,13R)-3-bromo-6-hydroxy-8,13-epoxylabd-14-en-1-one (2), by interpretation of their spectroscopic data as well as by X-ray crystallographic analysis.