Cellubrevin is a member of the synaptobrevin/VAMP family of SNAREs, which has a broad tissue distribution. In fibroblastic cells it is concentrated in the vesicles which recycle transferrin receptors but its role in membrane trafficking and fusion remains to be demonstrated. Cellubrevin, like the synaptic vesicle proteins synaptobrevins I and II, can be cleaved by tetanus toxin, a metallo-endop...

Clostridium perfringens, the most broadly distributed pathogen in nature, produces a prototype phospholipase C, also called α-toxin, which plays a key role in the pathogenesis of gas gangrene. α-Toxin causes plasma membrane disruption at high concentrations, but the role of intracellular mediators in its toxicity at low concentrations is unknown. This work demonstrates that α-toxin causes oxida...

We have previously reported that carbamoylcholine (carbachol), a recognized inhibitor of somatostatin release from D-cells, can act as stimulant following pretreatment of cells with pertussis toxin. In the present studies we have observed that pertussis toxin reverses the inhibitory effects of carbachol on D-cell stimulated with either cAMP or 12-O-tetradecanoyl-phorbol 13-acetate. Furthermore,...

The intracellular action on exocytosis of various forms of tetanus toxin was studied using adrenal medullary chromaffin cells, the membrane barrier of which has been removed by permeabilization with streptolysin O. Such cells still release catecholamines on stimulation with calcium. The two-chain form of tetanus toxin (67 nmol/l) strongly inhibited exocytosis, but only if dithiothreitol was pre...

OBJECTIVE Ulmi Pumilae Cortex(UPC) is a deciduous tree with uneven pinnate leaves and is classified as a subfamily of Ulmuceae and contains many pharmacologically active constituents. The aim of this study was to investigate the effects of UPC on the growth and survival of AGS cells, the most common human gastric adenocarcinoma cell lines. METHODS The AGS cells were treated with varying conce...

Purified Drosophila indirect-flight-muscle actin and arthrin, an actin-ubiquitin conjugate, were ADP-ribosylated by Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin. Phalloidin treatment inhibited the ADP-ribosylation of Drosophila actin and arthrin. Like actin, the ADP-ribose-arthrin linkage was sensitive towards hydroxylamine treatment, indicating arginine as the amino ac...

T h e t o x i c e f f e c t o f a f l a t o x i n s o n p i g s , their distribution in -and elimination from body tissues were studied in a series of experiments. Results showed that: 1. the response of growing pigs to diets containing 100, 200 or 400 p p b af latox in B 1 was in accordance with the increasing concentration of the toxin a n d in reverse order to the age o f the p igs . While t...

Bernheimer and Cantoni (1), in 1947, described an unusual "anti toxic" mechanism in mice, characterized by the development of a temporary state of resistance to the lethal effect of streptolysin O within hours of the intravenous administration of sublethal amounts of this toxin. Rowen and Bemheimer (2) subsequently found this induced refractoriness to be associated with an increased capacity of...

The Fusarium mycotoxins HT-2 toxin (HT2) and T-2 toxin (T2) are frequent contaminants in oats. These toxins, but also their plant metabolites, may contribute to toxicological effects. This work describes the use of 13C-assisted liquid chromatography-high-resolution mass spectrometry for the first comprehensive study on the biotransformation of HT2 and T2 in oats. Using this approach, 16 HT2 and...