The dynamics of glutathione species and ophthalmate concentrations in plasma from the VX2 rabbit model of secondary liver tumors.

PURPOSE: Available tumor markers have low sensitivity/specificity for the diagnosis of liver tumors. The present study was designed to evaluate the oxidoreductive status of the liver as surrogates of tumor subsistence and growth. METHODS: Glutathione species (GSH:GSSG), ophthalmate (OA) concentrations, and their turnover were measured in plasma of rabbits (n = 6) in their healthy state and in the state of tumor growth after implantation of the VX2 carcinoma in their liver. Tumors were allowed to grow for a period of 14 days when rabbits were sacrificed. Livers were removed and cysteine concentration was measured in liver tissue. RESULTS: Tumor growth was found in 100% of the rabbits. Concentration and labeling of GSH/GSSG were similar in experimental animals before and after tumor implantation and to sham animals. In contrast, OA concentration increased significantly in experimental animals after tumor implantation when compared to same animals prior to tumor implantation and to sham animals (P < .05). The concentration of cysteine, a precursor of GSH, was found to be significantly lower in the liver tissue adjacent to the tumor (P < .05). CONCLUSION: Disturbances in the oxidoreductive state of livers appear to be a surrogate of early tumor growth.

Phenolic glycosides from Exostema mexicanum leaves.

Phytochemical investigation of the leaves of Exostema mexicanum led to the isolation of two novel acylated flavonol glycosides 6, 7 and three glycosides 1-4 structurally belonging to the group of 4-phenylcoumarins. One of them, 5-O-beta-D-glucopyranosyl-4'-hydroxy-7-methoxy-4-phenylcoumarin (2), turned out to be new. Furthermore, the 4-phenylcoumarin aglycone 3'-hydroxy-4',5,7-trimethoxy-4-phenylcoumarin (5) was obtained. The in vitro cytotoxicity of 3-5 against the cell line ECV-304 was evaluated; the aglycone 5 was highly cytotoxic, whereas the glycosidic compounds 3 and 4 were inactive.

Hemangioendothelioma of the temporal bone with radiologic findings resembling hemangioma.

SUMMARY: Hemangioendotheliomas are rare vascular tumors that can affect bone. They account for 0.5% to 1.0% of malignant primary bone tumors. Only four cases have been reported involving the temporal bone. A 5-year-old child with grade II hemangioendothelioma of the right temporal bone is presented, and the radiologic findings on different imaging studies are described. The patient was treated with preoperative endovascular embolization followed by wide surgical resection. The imaging patterns of this malignant tumor may be similar to those of a benign lesion.

In vitro antiplasmodial activity of 4-phenylcoumarins from Exostema mexicanum.

The stem bark of Exostema mexicanum (Rubiaceae) is used in Latin American folk medicine as a quinine substitute for malaria treatment. Bioassay-guided fractionation of lipophilic and hydrophilic extracts from the stem bark and branches yielded two previously undescribed 4-phenylcoumarins: 4',8-dihydroxy-5,7-dimethoxy-4-phenylcoumarin (exomexin A) and 3',4'-dihydroxy-5,7,8-trimethoxy-4-phenylcoumarin (exomexin B). Together with five known derivatives the in vitro activities against a chloroquine-sensitive strain (poW) and a chloroquine-resistant strain (Dd2) of Plasmodium falciparum have been evaluated. The most lipophilic compound, 4',5,7,8-tetramethoxy-4-phenylcoumarin (O-methylexostemin) revealed the strongest antiplasmodial activity (IC50 values: 3.6 microg/ml [poW], 1.6 microg/ml [Dd2]).

Imaging of cranial meningitis and ventriculitis.

A spectrum of infectious diseases may affect the cranial meninges. Contrast-enhanced MR imaging and fluid-attenuated inversion-recovery MR techniques are superior to contrast-enhanced computed tomography for detecting and characterizing most pathologic meningeal conditions. In patients with meningitis, a major role of medical imaging is to identify potential complications such as hydrocephalus, extra-axial mass-forming infectious collections, parenchymal infarcts related to arteritis, ventriculitis, and associated underlying parenchymal abscesses or granuloma formations. Early diagnosis of such complications may reduce the rate of morbidity and mortality in this group of patients.