Thrombohemorrhagic Lesions Induced by Temporary Ischemia

SummaryTemporary ischemia of the rat’s hind paw induces severe thrombohemorrhagic lesions following sensitization by the intravenous injections of ferric dextrin and agar I. Other substances such as India ink and saccharated ferric oxide, which exhibit no thrombohemorrhagic sensitizing properties when a tourniquet, epinephrine or 5-HT are used separately as challengers, prove extremely effective upon application of the tourniquet if epinephrine is also injected into the contralateral paw. Scandium chloride, given intravenously, sensitizes the rat for the production of thrombohemorrhagic lesions by temporary ischemia of the dorsal skin but fails to induce similar changes after an equally severe ischemia of the paw. It is concluded that, following sensitization, two in themselves ineffective agents, can become active thrombohemorrhagic challengers upon conjoint application.</jats:p

Stress related changes of cell surface hydrophilicity in Bacillus subtilis

The changes of cell surface hydrophilicity in Bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, pH-shock, phosphate- and carbon-limitation.  Although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions.  An observed drop in intracellular GTP and/or ATP may be an element of the signal transduction pathway leading to an increase in surface hydrophilicity in response to environmental stresses.  Attachment of cells to soil particles under salt stress conditions is strongly influenced by the degS/degU two-component system, which thereby provides a mechanism for the bacteria to escape from the hostile environment