Life Sciences Commons^™

An Organ Culture Technique For Maintaining The Pulp Tissue Of Intact Human Teeth, John P. Devincenzo

Loma Linda University Electronic Theses, Dissertations & Projects

The size of explants in organ culture is limited by their ability to feed, respire, and excrete by diffusion. The perfusion procedure described in this report is not limited to a particular explant size. The test tissue was the adult human tooth.

In order to maintain the pulp tissue of the intact human tooth in organ culture, special precautions were taken to prevent internal necrosis and to allow diffusion of nutrients and waste products. Using aseptic technique, a standard tissue culture medium plus appropriate antibiotics were delivered to a glass manifold housed in an incubator with an atmosphere at 100% …

Automated Analysis Of Amino Sugars Using The Elson-Morgan Reaction, Lee Van Lenten

Yale Medicine Thesis Digital Library

A combined chromatographic and analytical system is described for the specific determination of amino sugars. An adaptation of the Elson-Morgan reaction has been made using the equipment of the Technicon AutoAnalyzer. The colorimetric procedure is based partly on the work of Lewy and McAllan . The Elson-Morgan reaction is a two-stage reaction which involves first the reaction of the amino sugar with acetic anhydride or 2 ,4pentanedione and the formation of cyclic intermediates by heating in an al kaline medium. In the second stage, the medium is acidifed and the intermediates coupled with p_-dimethylaminobenzaldehyde to give a colored product. In …

Saponin Content And Some Pod And Blossom Characteristics Of Alfalfa As Related To Seed Infestation By The Alfalfa Seed Chalcid, Ronald D. Morse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The alfalfa seed chalcid, Bruchophagus ruddi Guss., is a jet-black hymenopteran wasp. The destructive nature of this pest has been recognized since the latter part of the nineteenth century. Every year thousands of acres of alfalfa seed are destroyed, with infestation reaching as high as 8 5 percent in some areas. In Utah the chalcid annually ruins from 5 to 25 percent of the alfalfa seed. Much of this damage goes unnoticed, as infested seed is commonly blown out in the trash during harvesting and cleaning operations . The extent of damage is not restricted to the United States. Wherever …

The Complex Formation Of Silver Ion With Ribonucleic Acid, Guanosine, Inosine And Related Compounds And Peroxidase-Like Activity Of A Haemundecapeptide Prepared From Horse Heart Cytochrome C, José Angel Reinosa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance of nucleic acids in plant and animal cells as carriers of genetic information and as protein biosynthesis agents is well recognized. It is also known that nucleic acid is a component of all viruses.

Takahashi (45) and Fraenkel-Conrat (16) demonstrated that the protein component of tobacco mosaic virus is non-infectious to the host plant, although it is identical to the original virus morphologically. The virus ribonucleic acid (RNA) alone was infectious, however.

Deoxyribonucleic acid (DNA), which is present in chromosomes, displays a very specific function. The chromosome long has been accepted as the carrier of the hereditary unit, …

Compartmentation Of Glutamic Acid Metabolism In Brain Slices / Donald D. Clarke And Soll Berl Columbia Univ. School Of Medicine, N. Y. C., Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

The presence, in brain, of metabolic pools of glutamic acid have been demonstrated in vivo but not in tissue slices. Brain tissue slices prepared in the cold in Ringer's-bicarbonate containing 1% glucose and stored in an ice bath go not show compartmentation when incubated at 37 (10-20 min.) in a similar medium which contains tracer quantities of C aspartic acid, U.l.; the specific activity of glutamine remains considerably below that of glutamic acid. If such tissue slices are pre-incubated at 37° for 10 min. and then transferred to fresh medium containing radioactive tracer, after 10 min. at 37 , the …

Automation Of The Assay For Transglutaminase / Donald D. Clarke And Ruth Nicklas, Donald Dudley Clarke Phd, Ruth Nicklas

Chemistry Faculty Publications

Transglutaminase is an enzyme which catalyzes the Ca++-activated incorporation of amines into proteins. More detailed studies of the action of this enzyme showed that the incorporated amines displaced ammonia, and that only L-glutamine and not asparagine residues in the protein or peptide are substrates for this enzyme. This enzyme will not act on free glutamine, hence is not to be confused with glutaminase or transamidases which will act on free glutamine as a substrate. A variety of substituted glutamine peptides have been found to have substrate activity for this enzyme. Neidle and Acs, and more recently Folk and Cole, have …

Investigations On Lignins And Lignification Pt. Xxxi Characterization Of Metasequoia 'Milled-Wood' Lignin / By Michael J. Reale, Donald D. Clarke, Walter J. Schubert And F. F. Nord Laboratory Of Organic Chemistry And Enzymology), Fordham University, Bronx, New York, Michael J. Reale, Donald Dudley Clarke Phd, Walter J. Schubert, Friedrich F. Nord

Chemistry Faculty Publications

A young Metasequoia tree was debarked; its branches and heartwood were removed. The branches, sapwood and heartwood were separately ground to 8o mesh and air-dried. The moisture and lignin contents of these were determined. "Milled-wood" lignin was isolated from the sapwood sawdust, and was characterized by means of its ultraviolet and infrared absorption spectra. As a means of determining the empirical formula and the number of certain functional groups present in this lignin, an acetylated derivative and a phenylhydrazone were prepared. These were also studied spectroscopically. Elemental, methoxyl and acetoxyl analyses were performed on the original lignin and on its …

Electron Capture Properties Of Halogenated Amine Derivatives / By Donald D. Clarke, Sherwin Wilk, And Stanley E. Gitlow, Donald Dudley Clarke Phd, Sherwin Wilk, Stanley E. Gitlow

Chemistry Faculty Publications

The use of gas-liquid chromatography (G.L.C.) for the analysis of amines of biological interest is currently under investigation in our laboratory. An intensive study of the chromatographic properties of a number of derivatives was presented by VandenHeuvel et al. (1), and this laboratory in a short communication reported on the possible use of heptafluorobutyrylated amine derivatives (2). As was noted in this early communication, sensitivity considerations must maintain priority in any proposed assay because of the extremely small quantities of these compounds present in biological fluids. For this reason, we have chosen to employ the electron capture detector (3). Trifluoroacetyl …

Organo-Phosphorus Insecticides For Control Of Red-Legged Earth Mite And Lucerne Flea, J A. Button

Journal of the Department of Agriculture, Western Australia, Series 4

MOUNTING CONCERN over residue problems arising from the use of D.D.T. and other chlorinated hydrocarbon insecticides on pasture has highlighted the need for alternative chemicals capable of providing satisfactory control without undesirable side effects.

Genetic And Biochemical Aspects Of O-Hydroxycinnamic Acid Synthesis In Melilotus Alba, Herman J. Gorz, Francis A. Haskins, A. Kleinhofs

Department of Agronomy and Horticulture: Faculty Publications

In sweetclover (Melilotus alba Desr.) the cis- and trans-isomers of o-hydroxycinnamic acid occur primarily as the respective, β-D-glucosides. Available evidence indicates that these glucosides are formed via the following pathway: phenylalanine (formed from shikimic acid) → trans-cinnamic acid → o-coumaric acid (trans-o-hydroxycinnamic acid) → o-coumaryl glucoside (trans-β-D-glucosyl-o-hydroxycinnamic acid) → coumarinyl glucoside (cis-β-D-glucosyl-o-hydroxycinnamic acid). In tissues that are disrupted, coumarinyl glucoside is rapidly hydrolyzed by the action of endogenous β-glucosidase to yield coumarinic acid, which lactonizes spontaneously to form coumarin. The cu …