The antiallergic constituents of oolong tea stem were examined. The stem extracts inhibited the 48 h homologous passive cutaneous anaphylaxis (PCA) reactions or rats in a dose-dependent manner and showed the same extent of inhibitory activity as ketotifen. All antiallergic constituents from the stem were concentrated into chloroform and ethyl acetate fractions, when extracted by various solvents. These fractions were treated with polyvinylpolypyrrolidone (PVPP), which resulted in the elimination of antiallergic activity in the ethyl acetate fraction, suggesting that one of the antiallergic constituents may be tea catechins. Then, six kinds of catechins, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), -epicatechin (EC), (+)-catechin (C) and (-)-gallocatechin gallate (GCG), were isolated from the ethyl acetate fraction, and the inhibitory activity of these catechins on histamine release from rat peritoneal mast cells passively sensitized with anti-egg albumin (EA) IgE antibody was investigated. Among these catechins, significant inhibitory activity was observed in all the catechins except for EC. In addition, the inhibitory activity of GCG was greater than that of EGCG, which is well known to be an antiallergic constituent in tea. These results suggest that GCG may be a novel antiallergic constituent among tea catechins, and also the most potent.

The glial cells missing (gcm) gene in Drosophila encodes a GCM-motif transcription factor that functions as a binary switch to select between glial and neuronal cell fates. To understand the function of gcm in vertebrates, we isolated the zebrafish gcmb and analyzed the function of this gene using antisense morpholino oligonucleotides against gcmb mRNA (gcmb-MO) and transgenic overexpression. Zebrafish gcmb is expressed in the pharyngeal arch epithelium and in cells of the macrophage lineage. gcmb-MO-injected larvae show significantly reduced branchial arch cartilages. fgf3-MO-injected larvae display a similar phenotype to that of gcmb-MO-injected larvae with respect to the lack of pharyngeal cartilage formation. In addition, gcmb expression in the pharyngeal arches is down-regulated in fgf3-MO-injected larvae. The gcmb transgenic larvae show a protrusion of the lower jaw and abnormal spatial arrangement of the pharyngeal cartilage elements. These results suggest that gcmb is required for normal pharyngeal cartilage formation in zebrafish and that its expression is dependent on fgf3 activity.

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Specific hemodynamic changes in acute ischemia were investigated using a middle cerebral artery occlusion primate model and positron emission tomography. The cerebral blood flow (CBF), cerebral blood volume, oxygen extraction fraction (OEF), and cerebral metabolic rate for oxygen were measured 1, 3, and 9 hours after occlusion. OEF showed an increase in ischemic areas, and especially where CBF was below 18 ml/100 gm/min 1 hour after occlusion the OEF increased significantly (0.69 +/- 0.20, p < 0.05). Nine hours after occlusion, the OEF values were lower compared to those 1 and 3 hours after occlusion. Areas where CBF ranged from 18 to 31 ml/100 gm/min showed an increase in OEF at all times (p < 0.05). Clearly, OEF changes remarkably in the acute stage.

To evaluate irradiation effects on the metabolism of metastatic brain tumors treated by Gamma Knife radiosurgery, positron emission tomography (PET) and ¹H-magnetic resonance spectroscopy (MRS) studies were performed on five patients. The tumor origins were lung cancer in three patients and breast cancer in two. Treatment volume was 0.4–10.1 cm³ (mean: 5.5 cm³). The marginal dose to the tumor was 24–30 Gy (mean: 26.2 Gy). The follow-up period was 5–19 months (mean: 13.4 months). No patients had conventional whole-brain radiation therapy. ¹⁸F-fluoroboronophenylalanine (¹⁸FBPA) or ¹⁸F-fluorodeoxyglucose (¹⁸FDG) were used as tracers for the PET study. Using ¹H-MRS, several metabolites were simultaneously measured in metastatic brain tumor and adjacent brain. In the PET study of the representative case, the uptake rate of ¹⁸FBPA that is actively transported to the tumor decreased markedly 15 days after radiosurgery and continued to decrease thereafter. In the ¹H-MRS study, choline, which is characteristically high in metastatic brain tumors, also decreased over time. In two cases with suspected radiation injury, the enhanced region, which was decreased in size in early follow-up, enlarged progressively and was accompanied by edema. However, ¹⁸FBPA and ¹⁸FDG were not transported to the enhanced region. The peak of free lipid, which might show destruction of the cell membrane, was recognized in the enhanced region and adjacent brain in these cases. This study revealed that radiation effects on the metabolism of metastatic brain tumors occur at an early stage after radiosurgery and continue over several months. In particular, in the case of radiation injury, PET and ¹H-MRS studies made it possible to distinguish between regrowth of the tumor and radiation injury.