Synthetic and chemical studies on pheromones of some forest pest insects

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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Ultrastructural Localization of Acetylcholinesterase in the Arcuate Nucleus and Median Eminence of the Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079644 ◽

1977 ◽

Vol 35 ◽

pp. 440-441

Author(s):

K.A. Carson ◽

C.B. Nemeroff ◽

M.S. Rone ◽

J.S. Kizer ◽

J.S. Hanker

Keyword(s):

Choline Acetyltransferase ◽

Median Eminence ◽

Arcuate Nucleus ◽

Cholinergic Neurons ◽

Ultrastructural Localization ◽

Male Rats ◽

Neonatal Rats ◽

Good Marker ◽

Chemical Studies ◽

High Doses

Biochemical, physiological, pharmacological, and more recently enzyme histo- chemical data have indicated that cholinergic circuits exist in the hypothalamus. Ultrastructural correlates of these pathways such as acetylcholinesterase (AchE) positive neurons in the arcuate nucleus (ARC) and stained terminals in the median eminence (ME) have yet to be described. Initial studies in our laboratories utilizing chemical lesioning and microdissection techniques coupled with microchemical and light microscopic enzyme histo- chemical studies suggested the existence of cholinergic neurons in the ARC which project to the ME (1). Furthermore, in adult male rats with Halasz deafferentations (hypothalamic islands composed primarily of the isolated ARC and the ME) choline acetyltransferase (ChAc) activity, a good marker for cholinergic neurons, was not significantly reduced in the ME and was only somewhat reduced in the ARC (2). Treatment of neonatal rats with high doses of monosodium 1-glutamate (MSG) results in a lesion largely restricted to the neurons of the ARC.

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Structural and Chemical Studies of Pathological Fibers in Human Neurofibrillary Degeneration

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012031x ◽

1985 ◽

Vol 43 ◽

pp. 726-729

Author(s):

K.S. Kosik ◽

L.K. Duffy ◽

S. Bakalis ◽

C. Abraham ◽

D.J. Selkoe

Keyword(s):

Monoclonal Antibodies ◽

Alzheimer Disease ◽

Human Brain ◽

Neurofibrillary Tangles ◽

Morphological Analysis ◽

High Specificity ◽

Cytoskeletal Proteins ◽

Neuritic Plaque ◽

Protein Chemistry ◽

Chemical Studies

The major structural lesions of the human brain during aging and in Alzheimer disease (AD) are the neurofibrillary tangles (NFT) and the senile (neuritic) plaque. Although these fibrous alterations have been recognized by light microscopists for almost a century, detailed biochemical and morphological analysis of the lesions has been undertaken only recently. Because the intraneuronal deposits in the NFT and the plaque neurites and the extraneuronal amyloid cores of the plaques have a filamentous ultrastructure, the neuronal cytoskeleton has played a prominent role in most pathogenetic hypotheses.The approach of our laboratory toward elucidating the origin of plaques and tangles in AD has been two-fold: the use of analytical protein chemistry to purify and then characterize the pathological fibers comprising the tangles and plaques, and the use of certain monoclonal antibodies to neuronal cytoskeletal proteins that, despite high specificity, cross-react with NFT and thus implicate epitopes of these proteins as constituents of the tangles.

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High Voltage Electron Microscopy of Viral Inclusion Bodies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002117 ◽

1980 ◽

Vol 38 ◽

pp. 486-487 ◽

Cited By ~ 1

Author(s):

H.M. Mazzone ◽

W.F. Engler ◽

G. Wray ◽

A. Szirmae ◽

J. Conroy ◽

...

Keyword(s):

New York ◽

Environmental Protection Agency ◽

Inclusion Bodies ◽

Host Cells ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Viral Particles ◽

Pest Insects ◽

Viral Inclusion ◽

Insect Gut

Viral inclusion bodies isolated from infected pest insects are being evaluated by the U.S. Dept. of Agriculture as biological insecticides against their hosts. Our research on these inclusion bodies constitutes part of an effort to support their approval by the Environmental Protection Agency as insect control agents. The inclusion bodies in this study are polyhedral in shape and contain rod-shaped viral particles. When ingested by pest insects, the inclusion bodies are broken down in the insect gut and release the viral particles which infect and multiply in the nuclei of host cells. These viruses are termed nucleopolyhedrosis viruses (NPV) and are representatives of the baculoviruses (Wildy, P. 1971 IN J.L. Melnick, ed., Monographs in Virology, vol. 5, S.Karger, New York).

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