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I L Roth

Publications and source records attributed to I L Roth.

25 records · Page 2Linked to original sources
PubMed1970

Electron Microscopy of the Phagocytosis of Capsulated Bacillus anthracis.

The phagocytosis of capsulated vegetative cells of Bacillus anthracis in the mouse spleen was studied by thin sectioning techniques of electron microscopy. Mice were injected with autoclaved suspensions of capsulated and noncapsulated vegetative cells via the tail vein. The animals were killed 5, 10, and 30 min and 4 hr postinjection, with the central portion of the spleen being removed and procssed for electron microscopy. Fixation was with 2% KMnO(4) for 2 hr. Results of this study indicated that phagocytosis of autoclaved, capsulated anthrax bacilli was through the normal phagocytic process. The vesicular membrane or phagosome membrane was still present around these killed, capsulated organisms 4 hr postinjection. It is concluded that such cells possess no toxic principle to account for the supposed destruction of the phagosome membrane previously reported.

Journal Article↗
PubMed1969

Electron microscopic study of a slime layer.

Slime layers are being studied in our laboratories in an attempt to understand their functions in the control of pollution in natural streams. A method for fixing, staining, and embedding microorganisms in the intact slime has been developed. In this method, epoxy resin discs are placed in a holder and are introduced into a simulated stream. After various periods of time the discs are punched out of the holder into the fixative. The disc with the attached slime is fixed, stained (4% osmium tetroxide plus ruthenium red), dehydrated, and embedded in epoxy resin so that thin sections can be cut through the vertical plane of the slime mass. Such thin sections permit detailed examination of the attached layer, the surface-slime interface, the spatial relationships between cells in the vertical slime structure, and the strands of extracellular material between and around cells. No special attachment structures were noted as the cells appeared to be attached to the surface by extracellular material alone. This material was observed in strands and netlike forms between cells which are positioned 1 to 4 mum apart in the slime.

Bacteria↗