Erabutoxins a and b are neurotoxins isolated from venom of a sea snake Laticauda semifasciata (erabu-umihebi). Amino acid sequences of the toxins indicated that the toxins are members of a superfamily consisting of short and long neurotoxins and cytotoxins found in sea snakes and terrestrial snakes. The short neurotoxins to which erabutoxins belong act by blocking the nicotinic acetylcholine re...

results imply some transient retention of the toxinsecreting stem cells. Unfortunately, the investigators were unable to detect viable stem cells in the resection cavity after 72 hours by bioluminescence. Many potential agents against glioblastoma will be challenged by drug stability and poor blood-brain barrier permeability. Using neural stem cells to secrete tailored tumorspecific toxins or o...

Immunological tolerance to a soluble, partially purified fraction of histocompatibility (H)-2(a) antigen was induced in B10.D2 strain mice. The fraction used was obtained after chromatography on a Sephadex G-150 column. Tolerance of humoral-antibody formation (cytotoxins and hemagglutinins) was observed in mice injected with soluble antigen since birth, but cell-mediated immunity, as measured b...

INTRODUCTION . . , 175 MECHANISMS OF CARCINOGENESIS . . 176 BLOCKING AGENTS . . 178 PHASE I METABOLISM ACTIVATION BY MONOOXYGENASES . . 178 Free radical mediated damage . . 180 Alternative route to phase I metabolism quinone reductase (QR) . . 181 C O N J U G A T I O N BY PHASE I1 ENZYMES . . 183 INDIRECT EFFECTS V I A ENTERIC BACTERIAL METABOLISM , . 184 INDUCERS OF D N A REPAIR . . 185 SUPPRE...

The cytotoxic properties of cytotoxins (CTs) from snake venom are mediated by their interaction with the cell membrane. The hydrophobic pattern containing the tips of loops I-III and flanked by polar residues is known to be a membrane-binding motif of CTs. However, this is not enough to explain the difference in activity among various CTs which are similar in sequence and in 3D structure. The m...

To expand our knowledge of Helicobacter pylori virulence mechanisms, we used iTRAQ (isobaric tagging reagents for relative and absolute quantification)-based proteomic analysis to investigate the effect of H. pylori on gastric AGS tissue culture cells. In particular, we were interested in finding out which effects of H. pylori were dependent on the cytotoxins CagA and VacA. Protein analysis was...

An improved understanding of how intestinal bacteria cause disease has become increasingly important because of the emergence of new enteric pathogens, increasing threats of drug resistance, and a growing awareness of their importance in malnutrition and diarrhea. Reviewed here are the varied ways that intestinal bacteria cause disease, which provide fundamental lessons about microbial pathogen...

Alzheimer's disease (AD) is a familiar neurodegenerative disease in the elderly. In this paper, we will review current viewpoints of microglial activation, inflammatory regulatory systems, and their relationship with AD pathology and etiology. Microglia cells are macrophage and representative of the innate immune system in brain. AD brain is marked by obvious inflammatory features, in which mic...

The action of Clostridium difficile toxins A and B depends on inactivation of host small G-proteins by glucosylation. Cellular inositol hexakisphosphate (InsP6) induces an autocatalytic cleavage of the toxins, releasing an N-terminal glucosyltransferase domain into the host cell cytosol. We have defined the cysteine protease domain (CPD) responsible for autoprocessing within toxin A (TcdA) and ...

Bacteria of the genus Legionella are intracellular parasites and major human pathogens. They bind to surface receptors, penetrate eukaryotic cells and initiate complex disorders during phagocytosis. These disorders include inhibition of oxidative burst, a decrease in phagosome acidification, the blocking of phagosome maturation and changes in organelle trafficking. As a result, the microorganis...