Biological activity of compounds isolated from air condensates and frass of the bark beetle, Ips confusus

Bark beetles are among the most influential biotic agents in conifer forests, and forest management often focuses on bark beetle chemical communication for tree protection. Although acoustic communication occurs in many bark beetle species, we have yet to utilize acoustic communication for bark beetle control. Here, we describe the stridulatory organs and ‘stress’ chirps of the pinyon engraver, Ips confusus, a significant pest and mortality agent of pinyon pine in western North America. Only females possessed stridulatory organs and their stress chirps varied significantly in duration, pulses per chirp, and dominant frequency. We tested an array of acoustic-vibrational treatments into logs but were unable to disrupt male entry into logs or alter female–male interactions, female tunneling, and female oviposition. We found acoustic–vibrational treatments had little effect on I. confusus behavior and suggest further studies if acoustic methods are to be utilized for bark beetle control.

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Fine Structure of Degenerating and Regenerating Flight Muscles in a Bark Beetle, Ips confusus

Journal of Cell Science ◽

10.1242/jcs.6.3.807 ◽

1970 ◽

Vol 6 (3) ◽

pp. 807-819

Author(s):

N. M. G. BHAKTHAN ◽

J. H. BORDEN ◽

K. K. NAIR

Keyword(s):

Fine Structure ◽

Bark Beetle ◽

Structural Organization ◽

Flight Muscle ◽

Host Tree ◽

Muscle Degeneration ◽

Ips Confusus ◽

Flight Muscles ◽

Behavioural Significance

The flight muscles of the bark beetle Ips confusus undergo a pronounced degeneration within 4 days of introducing beetles into the bark of pine logs. Numerous lysosomes develop between the myofibrils, and the fibrils become greatly reduced in size. In female beetles many of the mitochondria and most of the myofilaments disappear from the muscle, and apart from lysosomes, tracheoles and a few fine granules, little structural organization remains in the fibres. The muscles of males degenerate to a lesser extent and, unlike those of females, contain numerous lipid globules in the degenerating condition. The significance of flight muscle degeneration as a possible prerequisite for reproduction in females is discussed. In males, flight muscle degeneration may have behavioural significance in confining the flightless insect to the host tree for repetitive mating and gallery maintenance.

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Fine structure of degenerating and regenerating flight muscles in a bark beetle, Ips confusus. II. Regeneration

Canadian Journal of Zoology ◽

10.1139/z71-013 ◽

1971 ◽

Vol 49 (1) ◽

pp. 85-89 ◽

Cited By ~ 19

Author(s):

N. M. G. Bhakthan ◽

K. K. Nair ◽

J. H. Borden

Keyword(s):

Bark Beetle ◽

Ponderosa Pine ◽

Flight Muscle ◽

Mitochondrial Fission ◽

Synthetic Activity ◽

Muscle Degeneration ◽

Giant Mitochondria ◽

Ips Confusus ◽

Multinucleated Cells ◽

Flight Muscles

The flight muscles of the bark beetle Ips confusus regenerate by two means, by formation and differentiation of new myoblasts, and by the regeneration of the old flight muscle itself. Mononucleated myoblasts appear in beetles which have been in the inner bark of ponderosa pine logs for 5 days. These cells apparently fuse with other myoblasts to form multinucleated cells. By the end of the ninth day of regeneration the myofilaments become attached to an incoherent Z line. By the 11th day of regeneration these differentiating myoblasts appear very much like the fibers of the regenerating old flight muscle.Simultaneously the fibers of the old degenerate muscles show signs of regeneration. On the sixth day after the beetles entered the bark, rearrangement of the existing degenerate myofilaments takes place. The incoherent and diffused Z line shows some degree of reorganization. Numerous ribosomes are present between the filaments. Between the 7th to 11th days of regeneration the mitochondria appear to fuse to form giant mitochondria up to five sarcomeres in length. These mitochondria by subsequent divisions give rise to numerous mitochondria. Almost invariably the line of mitochondrial fission is aligned with the Z line. The presence of numerous ribosomes and polysomes in the fibers indicate a high protein synthetic activity. By the end of the 13th day regeneration of the flight muscle appears complete and the beetles are now ready to reemerge. These results further confirm our earlier observation (Bhakthan et al. 1970) that flight muscle degeneration in I. confusus is a reversible process.

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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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