Antimutagenicity and induction of anticarcinogenic phase II enzymes by basidiomycetes.

Extracts from Phellinus linteus, Phellinus igniarius, and Agrocybe cylindracea have been tested for their antimutagenic properties against direct-acting mutagens [4-nitro-o-phenylenediamine (NPD) and sodium azide (NaN(3))] and indirect-acting mutagens [2-aminofluorene (2-AF) and benzo[a]pyrene (B[a]P)], using the Salmonella typhimurium tester strains TA 98 and TA 100. In addition, the chemopreventive potentials of these extracts to induce NAD(P)H:quinone oxidoreductase (QR) and glutathione S-transferase (GST) activities and glutathione (GSH) level extracts from the filtrate of the cultured broth of P. linteus, polysaccharide extracts from the cultured broth (PI I) and mycelia (PI II) and water extract of fruiting bodies (PI II) of P. igniarius, and polysaccharide extracts from the cultured broth (AC I) and mycelia (AC II) of A. cylindracea showed inhibitory effects on the mutagenic activities induced by the direct-acting mutagens, NPD and NaN(3), and the indirect-acting mutagens, 2-AF and B[a]P. QR was induced with PI I, PI II, AC I, and AC II, and GST activity was induced with PL I, PL II, PI I, PI II, PI III and AC I in murine Hepa1c1c7 cell culture. In addition, PL I, PL II, PI I, PI II, PI III and AC II increased glutathione level. These results suggest that P. linteus, P. igniarius, and A. cylindracea have antimutagenic activities and may play a role in the prevention of cancer by inducing QR and GST activities and increasing GSH level.

Proteoglycan in porcine aortic tissue after cryopreservation.

This study was to investigate the effects of cryopreservation on proteoglycans of arterial conduit tissue. Proteoglycans from fresh and cryopreserved porcine aorta tissues were extracted with 4 M guanidine hydrochloride (Gdn-HCl) at 4 degrees C in the presence of protease inhibitors. From the tissue extracts, proteoglycans were isolated by cesium chloride (CsCl) isopycnic centrifugation and fractionated by gel filtration. Quantitative analysis of extracted proteoglycans revealed that the content of proteoglycans from cryopreserved tissue, measured as the amount of uronate and protein per unit weight of wet tissue, was similar to that from fresh tissue (0.44 +/- 0.300 versus 0.43 +/- 0.007 mg uronate/g wet tissue and 3.14 +/- 0.039 versus 2.64 +/- 0.015 mg protein/g wet tissue). Gel permeation column chromatography studies suggested that proteoglycans present in three CsCl fractions (I, II, and III) from cryopreserved tissue have approximately the same molecular weights as those from fresh tissue; Kav = 0.13 and 0.47 (I), 0.20 (II), and 0.43 (III) from cryopreserved tissue versus Kav = 0.13 and 0.50 (I), 0.23 (II), and 0.40 (III) from fresh tissue. These studies indicate that there is no significant alteration in the content and molecular size of proteoglycans in properly cryopreserved aortic tissue.

Proteoglycan content in fresh and cryopreserved porcine aortic tissue.

Quantitative analysis of proteoglycans (PGs) revealed that the content of PG material from cryopreserved aorta, measured as uronate-positive material, was similar to that from fresh tissue (440 +/- 30 versus 430 +/- 7 micrograms/g wet tissue). Gel permeation column chromatography studies suggested that three PG fractions from cryopreserved tissue had molecular weights similar to PG fractions from fresh tissue; K(av) = 0.13, 0.47 (I), 0.20 (II), and 0.43 (III) from cryopreserved tissue and K(av) = 0.13, 0.50 (I), 0.23 (II), and 0.40 (III) from fresh tissue. Sequential extraction of tissue with guanidine-HCl (Gdn-HCl) followed by digestions with collagenase, elastase, and papain also demonstrated that there was no difference between fresh and cryopreserved tissues in the distribution of PGs in the extracts. Transmission electron microscopy analysis revealed less densely packed collagen fibers in cryopreserved tissues compared to fresh tissues. These studies indicate that there is no significant alteration in the content, molecular size, or distribution of PGs in properly cryopreserved tissue.

Intra-carotid thrombolytic therapy in acute ischemic stroke of carotid arterial territory.

Intra-carotid urokinase (UK) infusion in 20 patients with acute internal carotid artery (ICA) territorial ischemic stroke achieved immediate recanalization in 45% and the clinical outcome in patients with recanalization was superior to that of patients without recanalization. The procedure was most effective in patients with smaller arterial occlusions: 7 of 10 patients with MCA branch occlusions (M2 to M4) achieved recanalization compared to only 2 of 10 with distal ICA or M1 occlusions, which should be an important issue for the critical evaluation of the efficacy of thrombolytic therapy (TT). Hemorrhagic transformation was observed in 9 patients on CT scan; petechial hemorrhage in 5 and intraparenchymal hematoma formation in 4. Among 4 patients with hematoma formation, clinical deterioration was seen in 3 cases and the angiography at the immediate end of the UK infusion showed recanalization in only one patient. The average dose of UK in patients with parenchymal hematoma formation was higher than that of patients without hemorrhagic transformation (123.3 x 10(4) units vs 101 x 10(4) units). The administration of a large dose of UK, probably more than 100 x 10(4) units, and the absence of immediate recanalization seemed to increase the risk of parenchymal hematoma formation. Despite the effort of investigators, the in-hospital time delay for the TT was significant which was mainly related to the time consuming preparation for angiography especially during night. A more effective system for the earlier intervention of acute ischemic stroke needs to be developed.