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Larval Parasitism Of Psilocorsis Spp. (Lepidoptera: Oecophoridae), Leaftiers Of Central Missouri Oaks, J. Pasek, W. Kearby

Judith E Pasek

Larval parasitism of 3 Psilocorsis species in central Missouri forests averaged 22% for the years 1977-1979. Twenty-three species of parasitoids were reared in the laboratory from the larvae collected. Seventeen species emerged from P. reflexella Clemens, 14 from P. quercicella Clemens, and 10 from P. cryptolechiella (Chambers). The most abundant parasitoids were the braconids Apanteles n. sp., Agathis calcarata (Cresson), and A. cincta (Cresson); the eulophid Elachertus proteoteratis Howard; the ichneumonid Diadegma psilocorsis Walley; and the 3 closely related pteromalids, Perilampus fulvicornis Ashmead, P. prothoracicus Smulyan, and P. n. sp. Elachertus proteoteratis was reared only from P. reflexella. Twenty-three new …

Rapid Decline In Acetylcholine Release And Content Of Rat Extensor Digitorum Longus Muscle After Denervation, Diana Linden, Michael Newton, Alan Grinnell, Donald Jenden

Diana Linden

The amount of acetylcholine (ACh) and choline (Ch) in normal and denervated rat extensor digitorum longus (EDL) muscles, as well as that released spontaneously from these muscles, was determined by an extremely sensitive gas chromatographicmass spectrometric assay method. We found decreases in ACh content and spontaneous, resting ACh release as early as 8 h after denervation. The ACh content decreased to a plateau of 30% of control by 11 h; ACh release attained a plateau of 50% of control several hours later. These results showed that in denervated EDL muscles ACh content and spontaneous release (measured biochemically) decreased before nerve-evoked …

The California Gray Whale (Eschrichtius Robustus): A Review Of The Literature On Migratory And Behavioral Characteristics, James Bird

James E Bird

The literature search presented in Appendix A was performed to characterize the normal migratory behavior of the gray whale and to determine if introduced sound from a variety of sources, including offshore oil and gas development, would have an observable effect on that behavior. Because of the limited data on behavioral reaction of gray whales to noise and disturbance, we have also included in this literature review information on the behavioral reaction of other baleen whale species.

Opportunistic Feeding On Whale Fat By Wilson's Storm-Petrels In The Western North Atlantic, P Payne, Kevin Powers, James Bird

James E Bird

No abstract provided.

Justice And The Treatment Of Animals, Michael Pritchard

Michael Pritchard

Purification And Properties Of A Hela Cell Enzyme Able To Remove The 5'-Terminal Protein From Poliovirus Rna, Victor Ambros, David Baltimore

Victor R. Ambros

Using a rapid phenol extraction assay, an enzyme was purified from uninfected HeLa cells that can cleave the 5'-terminal protein (VPg) from poliovirus RNA. Both cytoplasmic and nuclear extracts had enzymes with similar behavior. A polypeptide of molecular weight 27,000 was the major one present in the purified preparation. Assuming that this protein is the enzyme, a very low turnover number was calculated for it. The purified enzyme would cleave the tyrosine-phosphate bond linking VPg to poliovirus RNA with minimal degradation of the RNA or of VPg. If the RNA was first treated with proteinase K to degrade VPg, leaving …

Biosynthesis And Degradation Of Acetylcholine Receptors In Rat Skeletal Muscles. Effects Of Electrical Stimulation, Diana Linden, D.M. Fambrough

Diana Linden

Synthesis and degradation of acetylcholine receptors in rat skeletal muscles were measured in organ culture. The rate of de novo biosynthesis and incorporation of acetylcholine receptors into extrajunctional membranes of denervated muscles was measured by determining the rate of appearance of [1] [2H, 13C, 15N]-acetylcholine receptors when muscles were cultured in medium containing [1] [2H, 13C, 15N]-amino acids. Denervated extensor digitorum longus and soleus muscles were found to synthesize new receptors for several days in organ culture at an average rate of 1.4%/h. The degradation rates for extrajunctional and junctional acetylcholine receptors were estimated by irreversibly labeling acétylcholine receptors on …

Rna Sequencing Provides Evidence For Allelism Of Determinants Of The N-, B-, Or Nb- Tropism Of Murine Leukemia Viruses, Jean Rommelaere, Helen Donis-Keller, Nancy Hopkins

Helen Donis-Keller

Previous genetic and biochemical studies identified three large RNAase T1-resistant oligonucleotides, each associated with either the N-, B- or NB-tropism of murine C-type viruses of BALB/c origin. These oligonucleotides were shown to lie in the 5′ third of the oligonucleotide maps of their respective viruses. We sequenced the three oligonucleotides and found that they share a 10 base sequence. Together these observations provide good evidence that the determinants of N-, B- or NB-tropism monitored by the three oligonucleotides are allelic.The oligonucleotides associated with N- and B-tropism differ in sequence at four of sixteen nucleotides, while the B- and NB-tropism-associated oligonucleotides …

An Enzymatic Activity In Uninfected Cells That Cleaves The Linkage Between Poliovirion Rna And The 5' Terminal Protein, Victor Ambros, Ralf Pettersson, David Baltimore

Victor R. Ambros

The 5' terminal protein (VPg) on poliovirion RNA can be removed by cell-free extracts from a variety of uninfected cells. This soluble enzymatic activity is found in both nuclear and cytoplasmic extracts of heLa cells and is activated by Mg++. The enzyme activity cleaves the tyrosine-phosphate bond that links the protein to the RNA. In a partially purified form it has insufficient nonspecific protease or nuclease activity to account for its action. The existence of this enzyme implies that poliovirus RNA is translated in cell-free extracts in a form that lacks the 5' terminal protein. The role of this enzyme …

Protein Is Linked To The 5' End Of Poliovirus Rna By A Phosphodiester Linkage To Tyrosine, Victor Ambros, David Baltimore

Victor R. Ambros

Purification and partial characterization of the poliovirus RNA-linked protein (VPg) are described. VPg has been freed from the RNA by ribonuclease digestion and phenol extraction. Gel filtration chromatography of VPg-pUp (labeled with 32P) in 0.5% sodium dodecyl sulfate or 6 M guanidine HCl indicates that it has a molecular weight of about 12,000. VPg is bound to the 5' end of poliovirion RNA by a phosphodiester bond between a tyrosine residue in the VPg molecule and the 5'-terminal uridine. After acid hydrolysis of [3H]tyrosine-labeled VPg-pU, free tyrosine can be released by venom phosphodiesterase. Acid hydrolysis of VPg-p labeled with either …

Mapping Adenines, Guanines, And Pyrimidines In Rna, Helen Donis-Keller, Allan Maxam, Walter Gilbert

Helen Donis-Keller

The positions of adenines, guanines, and pyrimidines can be determined by partial nuclease digestion of a terminally labeled RNA molecule. In urea, at elevated temperatures, RNase T1 generates a pattern reflecting cleavage at guanines while RNase U2 cleaves only at adenine. A limited alkaline hydrolysis provides a continuum of fragments derived from breaks at every phosphodiester bond. The reaction products are electrophoretically fractionated by size in adjacent lanes of a polyacrylamide gel. An autoradiograph of the gel displays the sequence up to 100 nucleotides from the end of the molecule, although uracil cannot as yet be distinguished from cytosine. These …

Separation Of Quantitation Of Intracellular Forms Of Poliovirus Rna By Agarose Gel Electrophoresis, Martinez Hewlett, Shmuel Rozenblatt, Victor Ambros, David Baltimore

Victor R. Ambros

Intracellular poliovirus-specific RNA species can be measured directly by electrophoresis of total cytoplasmic nucleic acids through 1% agarose gels, resulting in the separation of single- and double-stranded forms of poliovirus RNA from each other and from HeLa cell 28S ribosomal RNA. Single-stranded RNA molecules differing by only 15% in length are resolved in this gel system. RNA species can be visualized as fluorescen bands appearing after staining of the gels with ethidium bromide and observation under ultraviolet illumination. The total amount of RNA can be determined by densitometric quantitation of the fluorescent response. In this way, the amount of poliovirus-specific …

Growth Forms Of Opuntia Compressa (Cactaceae) In Florida Sandridge Habitats, Warren Abrahamson, J. Rubinstein

Warren G. Abrahamson, II

No abstract provided.

Reproductive Strategies Of Dewberries, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.

Reproduction Of Rubus Hispidus L. In Different Habitats, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.

A Forebrain Visual Projection In The Frog (Rana Pipiens), Edward Gruberg, Victor Ambros

Victor R. Ambros

In the frog (Rana pipiens) using a modification of the Fink-Heimer degeneration stain, a projection was traced from the lateral anterior thalamus via the lateral forebrain bundle to the ipsilateral striatum in the ventrolateral area of the forebrain. Striatal degeneration extended from the anterior commissure to the olfactory bulb. Single-unit microelectrode recording revealed that this area contained visual units that responded to the on and off of light.

Growth Form And Reproductive Effort In Goldenrods, Warren Abrahamson, M. Gadgil

Warren G. Abrahamson, II

No abstract provided.