Biological Activity of Phyllostine, a Phytotoxic Compound Isolated from the Culture Filtrate of Phyllosticta sp.

The culture filtrate of Alternaria triticina Prasada & Prabhu inhibited germination and root elongation of seeds of a resistant variety (HD 1982) and a susceptible variety (Kalyan Sona) of wheat. The filtrate-induced symptoms on the leaves of wheat plants were similar to those induced by the fungus. Thin-layer chromatographic analysis of the crude toxin extracted in n-butanol, acetone, and petroleum ether revealed the presence of more than one phytotoxic compound in the culture filtrate of A. triticina. The toxic principles were thermostable and nonspecific and inhibited the growth of wheat. The possible role of toxic metabolites during pathogenesis is suggested.

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Virus-Like Particles in a Human Breast Cancer: Structural Similarity to Previously Reported Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072332 ◽

1973 ◽

Vol 31 ◽

pp. 378-379

Author(s):

G. Kasnic ◽

S. E. Stewart ◽

C. Urbanski

Keyword(s):

Breast Cancer ◽

Biological Activity ◽

Human Breast Cancer ◽

Osteogenic Sarcoma ◽

Human Tumor ◽

Structural Similarity ◽

Cell Tumor ◽

Human Breast ◽

Human Tumor Cell ◽

Type Particle

We have reported the maturation of an intracisternal A-type particle in murine plasma cell tumor cultures and three human tumor cell cultures (rhabdomyosarcoma, lung adenocarcinoma, and osteogenic sarcoma) after IUDR-DMSO activation. In all of these studies the A-type particle seems to develop into a form with an electron dense nucleoid, presumably mature, which is also intracisternal. A similar intracisternal A-type particle has been described in leukemic guinea pigs. Although no biological activity has yet been demonstrated for these particles, on morphologic grounds, and by the manner in which they develop within the cell, they may represent members of the same family of viruses.

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Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090270 ◽

1976 ◽

Vol 34 ◽

pp. 58-59

Author(s):

John L. Beggs ◽

John D. Waggener ◽

Wanda Miller

Keyword(s):

Spinal Cord ◽

Biological Activity ◽

Horseradish Peroxidase ◽

Transport Mechanism ◽

Vasogenic Edema ◽

Vesicular Transport ◽

Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

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