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Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson Jan 1994

Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson

Chemistry Faculty Publications

Haemophilus ducreyi, a cause of genital ulcer disease in developing countries, appears to facilitate the heterosexual transmission of the human immunodeficiency virus in Africa. Despite an increase in studies of this gram-negative human pathogen, little is known about the pathogenesis of chancroid. Our studies have shown that the lipooligosaccharides (LOS) of H. ducreyi may play an important role in ulcer formation. Monoclonal antibody and mass spectrometric analyses identified a terminal trisaccharide present on H. ducreyi LOS that is immunochemically similar to human paragloboside. This epitope is present on the LOS of Neisseria gonorrhoeae, and it may be the site of …


The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy Jul 1993

The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy

Chemistry & Biochemistry Theses & Dissertations

Grape seed extract is being marketed in France for cardiovascular use and skin care. The active constituents of both these drugs are certain polyphenols called procyanidins. A similar seed extract has now been obtained from Virginia Chardonnay grape seeds. Ten of the major components in this extract have been isolated in their pure form by the semi-preparative HPLC separation on a YMC ODS-AQ (Octadecylsilane-AQ) column. The ODS-Aq column has been shown to have a better resolving capacity compared to the Spherisorb ODS (Octadecylsilane) column previously described in the literature. This has been attributed to the ODSAQ support which has both …


Improved Synthesis Of 5-Methylbenz(A)Anthracene, Jia Che, Dominic T.C. Yang Jan 1987

Improved Synthesis Of 5-Methylbenz(A)Anthracene, Jia Che, Dominic T.C. Yang

Journal of the Arkansas Academy of Science

A revised synthesis of 5-methylbenz(a)anthracene is reported. It involves only three simple and convenient steps starting from a commercially available compound, and gives a 82% overall yield. Bromination of 5-methylbenz(a)anthracene with N-bromosuccinimide (NBS) in carbon tetrachloride furnishes 5-bromomethylbenz(a)anthracene in a 92% yield. When bromination is carried out using dimethylformamide as the solvent, 7-bromo-5-methylbenz(a)anthracene is formed as the exclusive product.


Part I: The Synthesis Of New Potential Insecticides. Part Ii: New Aromatic Nucleophililic Subsitution Reactions, Fluoroalkoxylation And N,N-Dimethylamination, Cesar Colon Oct 1983

Part I: The Synthesis Of New Potential Insecticides. Part Ii: New Aromatic Nucleophililic Subsitution Reactions, Fluoroalkoxylation And N,N-Dimethylamination, Cesar Colon

Retrospective Theses and Dissertations

A series of routes are described for the synthesis of new potential insecticides which are symmetrical or asymmetrical similogs of 2,5-Bis (dichloropheny1)-1,3,4-oxadiazole and its precursor diacyl hydrazine. Also two new aromatic nucleophilic substitution reactions are discussed. Activated aryl halides are reacted with fluorinated alkoxide anions. In all cases, substitution of the halogen by a fluoroalkoxy group was observed, and activated aryl halides are reacted with HMPA as an N, N-dimethyl aminating agent. In all cases, substitution of the halogen by a dimethyl amino group was observed. The effect of the activating group and the leaving group is described and a …


Synthesis Of Potential Insecticides And New Synthetic Applications Of Vinamidinium And Azavinamidinium Salts: Reactions With Reducing Agents And Nitro Compounds, Michael J. Lizzi Apr 1982

Synthesis Of Potential Insecticides And New Synthetic Applications Of Vinamidinium And Azavinamidinium Salts: Reactions With Reducing Agents And Nitro Compounds, Michael J. Lizzi

Retrospective Theses and Dissertations

This report discusses the research conducted in two areas: the synthesis of potential insecticides and the investigation of vinamidinium and azavinamidinium salt chemistry. Firstly, four classes of compounds were synthesized and characterized in the investigation of new potential insecticides. These classes of compounds include a-formamidine methyl esters, amidines, diacylhydrazines and 2,5-disubstituted-1,3,4-oxadiazoles and were characterized via NMR and infrared spectroscopy. This account also reveals and discusses the experimental conditions and procedures necessary for the preparation of these potential insecticides. Secondly, the reaction of [ 3-(dimethyl amino)-2-azaprop-2-en-1-ylidene] dimethyl ammonium chloride (Gold's Reagent) with nucleophiles such as activated (nitro) methylene compounds was examined …


Biological And Chemical Evaluation Of The Aquatic Environment Of Selected Undeveloped Kentucky Lake Embayments, Marshall Gordon, Morgan E. Sisk Dec 1976

Biological And Chemical Evaluation Of The Aquatic Environment Of Selected Undeveloped Kentucky Lake Embayments, Marshall Gordon, Morgan E. Sisk

KWRRI Research Reports

This report describes research involving biological and chemical analysis of two undeveloped embayments on Kentucky Lake, namely Anderson and Vickers Bays. Field and laboratory studies were made to assess current biotic standing crops, limnological conditions, levels of inorganic and organic pollutants in the embayments.


The Synthesis Of Analogs Of Toxoflavin And Fervenulin As Potential Antimetabolites, Bernadette Kuo Billings Apr 1976

The Synthesis Of Analogs Of Toxoflavin And Fervenulin As Potential Antimetabolites, Bernadette Kuo Billings

Theses and Dissertations

The synthesis of analogs of toxoflavin: 1,3,4,6-tetramethyl-1,5,6, 7-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 1,6-dimethyl-3,4-diphenyl-1,5,6,7-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 3,5,7-trimethyl-8-phenyl-2,3,4,8-tetrahydropyrido[2,3-d]-2,4-pyrimidinedione are discussed. The synthesis of analogs of fervenulin: 3,4,6-trimethyl-5,6,7,8-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 6-methyl-3,4-diphenyl-5,6,7,8-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 2-hydroxy-3,5,7-trimethyl-4(3H)pyrido[2,3-d]-2,4-pyrimidinone are discussed. Several intermediates have been prepared: 6 -methylamino-3-methyluracil by a new method; 6-n-propylamino-3-methyluracil: 6-n-butylamino-3-methyluracil and 3-ethyl-2-ethylthio-2-hydroxy-4(3H)pyrimidinone.


Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation Jan 1971

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …


The Effects Of Indomethacin On A Strain Of Fibroblasts Cultivated In Vitro, John Thomas Mccloskey Jan 1971

The Effects Of Indomethacin On A Strain Of Fibroblasts Cultivated In Vitro, John Thomas Mccloskey

University of the Pacific Theses and Dissertations

Man has always searched for greater understanding of himself and his environment. As a result, much scientific investigation has been directed towards the understanding of the life process. In recent years, such scientific inquiry has become increasingly focused on the fundamental biochemical events taking place at the cellular, subcellular, and molecular levels. In the course of investigation into the nature of living things, research has often necessitated the development of new techniques and investigational tools to serve as experimental systems. Very often such new methods have made possible the discovery of previously unknown processes. One very interesting and useful investigational …


Trace Metal Analysis Of Barren River And Nolin River Reservoirs By Atomic Absorption Spectroscopy, Mary Jo Kennedy Jul 1969

Trace Metal Analysis Of Barren River And Nolin River Reservoirs By Atomic Absorption Spectroscopy, Mary Jo Kennedy

Masters Theses & Specialist Projects

This research was part of a project underway at Barren River and Nolin River Reservoirs in south-central Kentucky. The research was partially supported by a grant through the Sport Fishing Institute, Washington, D.C.

The study reported herein was concerned with the analysis of trace metal concentrations in the two reservoirs. It is believed that the fish population may in part depend upon the trace metals present in the water. It is anticipated that the data presented in this paper will eventually be correlated with the biology studies of the reservoirs being carried out by the Department of Biology of Western …


Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration Oct 1968

Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration

Publications (WR)

This report fulfills the request of the Colorado River Basin Project, Denver, Colorado, to determine the effects of municipal and industrial wastes on the aquatic life in selected waters of the Colorado River Basin. These studies were conducted with the assistance of personnel from the Colorado River Basin Project.


The Value Of Including Chemistry Content In The Study Of High School Biology, Ramon Duane Buckley Jan 1957

The Value Of Including Chemistry Content In The Study Of High School Biology, Ramon Duane Buckley

Dissertations and Theses @ UNI

The purpose was to evaluate the effect of including some definite chemistry content in high school biology. This evaluation was made by comparing outcomes of instruction in two different groups of a high school biology course. The two groups were equated in terms of the intelligence quotients, the sex, and the previous achievement in biology of the class members. The comparative gains in factual knowledge were measured by means of an evaluation test. The comparative gains in appreciations and interests in biology were measured with a questionnaire.


A Chemical And Biological Study Of The Waters Of Elephant Butte Reservoir As Related To Fish Culture, John Greenbank Jun 1937

A Chemical And Biological Study Of The Waters Of Elephant Butte Reservoir As Related To Fish Culture, John Greenbank

Chemistry and Chemical Biology ETDs

The investigation of fresh-water lakes with respect to fish and other aquatic life had its beginning in Europe in the latter half of the nineteenth century. Probably the only man who may be considered to be the founder of the science of limnology was F. A. Forel, of the University of Lausanne Switzerland. Professor Forel’s work was the start of a rapidly developing branch of study, not only in Europe, but also presently in North America.