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Effect Of Membrane Filtration Of Antimalarial Drug Solutions On In Vitro Activity Against Plasmodium Falciparum, J. Kevin Baird, C. Lambros Jan 1984

Effect Of Membrane Filtration Of Antimalarial Drug Solutions On In Vitro Activity Against Plasmodium Falciparum, J. Kevin Baird, C. Lambros

United States Public Health Resources

Antimalarial activities ofchloroquine, mefloquine, amodiaquine, and quinine in vitro against Plasmodium falciparum were diminished as a consequence ofmembranefiltration. Filtered drug solutions gave ID50 values up to 25-fold greater than those of non-filtered (ethanol-sterilized) drug solutions. Loss ofactivity byfiltration was overcome by increasing the drug concentration prior to filtration. Water solutions filtered through Millex-GSfilter units consistently showed an absorbance maximum at 277 nm, accompanied by a lesser peak at 225 nm. Water filtrates from Nucleopore and Millex-G Vfilters showed no absorbance at 277 nm and only slight absorbance was evidentfor the Gelmanfilter unit. Activity losses were attributed to extractable contaminating …


Electron Microscopic Investigations Of The Cell Structure In Fresh And Processed Vegetables (Carrots And Green Bean Pods), Monika Grote, Hans Georg Fromme Jan 1984

Electron Microscopic Investigations Of The Cell Structure In Fresh And Processed Vegetables (Carrots And Green Bean Pods), Monika Grote, Hans Georg Fromme

Food Structure

The cell structure of fresh, blanched, boiled. dried and rehydrated tissues from carrot roots and green bean pods was examined in the scanning and/or transmission electron microscope. The secondary phloem of carrot roots represents a typical plant storage parenchyma characterized by a high starch and lipid content. Green bean pods show many characteristics of assimilation tissue (e.g. chloroplasts). but they also contain a considerable amount of starch. Blanching, boiling, de- and rehydration affect the texture of both vegetables in a similar way: swelling of cell walls. maceration of tissue during blanching and boiling coupled with a granular denaturation of cytoplasm. …


The Effects Of Microwave Energy And Convection Heating On Wheat Starch Granule Transformations, N. K. Goebel, J. Grider, E. A. Davis, J. Gordon Jan 1984

The Effects Of Microwave Energy And Convection Heating On Wheat Starch Granule Transformations, N. K. Goebel, J. Grider, E. A. Davis, J. Gordon

Food Structure

Wheat starch-water dispersions at 1:1, 1:2, 1:4, and 5 95 (w/w) starch:water ratios, representing systems with varying levels of water availability , were heated under static conditions to 75°C by microwave energy at two power settings and by convection heating. Starch granule swe lling was evaluated by light and scanning electron microscopy. Six stages in swelling were identified on the basis of s welling of small and large granules and development of an extragranular matrix. The range of swelling stages found in different locations within a sample decreased as water became more available and less limiting. At each starch:water ratio, …


The Effect Of Salt And Pyrophosphate On The Structure Of Meat, C. A. Voyle, P. D. Jolley, G. W. Offer Jan 1984

The Effect Of Salt And Pyrophosphate On The Structure Of Meat, C. A. Voyle, P. D. Jolley, G. W. Offer

Food Structure

Our obective was to determine whether or not salt and pyrophosphate have the same effect on the structure of pieces of meat as they have on isolated myofibrils. Blocks of pig M. longissimus dorsi were incubated in solutions of sodium chloride at pH 5.5 or sodium chloride plus sodium pyrophosphate at pH 5.5 or 8.0. The blocks were obtained from fresh (24h post- mortem) or aged (72h post-mor tem) muscle and incubated for 5 or 24h with minimal agitation. There was considerable uptake of water by the tissue especially at the higher pH and longer times.

Electron microscopy of the …


The Role Of Recognition In Plant Disease, J. M. Daly Jan 1984

The Role Of Recognition In Plant Disease, J. M. Daly

Department of Biochemistry: Faculty Publications

As noted by Sequeira (110,111), the term recognition has become very popular in the literature of host-pathogen interactions over the last ten years. Despite recent facile usage, its meaning is not always clear to me. Recognition is defined by Clarke & Knox (16) as the "initial event in cell-cell communication that elicits a defined biochemical, physiological, or morphological response." This requires the not-so-easy task of defining "initial event" and "communica­ tion" with precise chemical or physical mechanisms. For pathologists, Se­ queira (110) has provided a more restricted meaning: "An early specific event that triggers a rapid, overt response by the …


Artefacts In Conventional Scanning Electron Microscopy Of Some Milk Products, Miloslav Kalab Jan 1984

Artefacts In Conventional Scanning Electron Microscopy Of Some Milk Products, Miloslav Kalab

Food Structure

Artefacts develop due to changes in the microstructure of the sample under study because of inappropriate preparatory steps and/or due to distortion of the images of properly prepared samples during operation of the microscope. Of a wide variety of possible artefacts. only those occurring mast frequently have been selected and ilustrated with micrographs. In milk powders, the most common artefacts are the recrystallization of lactose in a humid atmosphere, "1 ine" and "dark-area" charging artefacts, and electron beam damage. In moist milk products, artefacts may arise at any preparatory step, such as sampling, fixation, dehydration and critical-point drying or freezing …


A Biosystematic Study Of The Fern Genus Lygodium In Eastern North America, Violet M. Brown Jan 1984

A Biosystematic Study Of The Fern Genus Lygodium In Eastern North America, Violet M. Brown

Retrospective Theses and Dissertations

The mainly tropical genus Lygodium differs from other ferns in that the fronds are indeterminate and are vine-like. A single species, L. palmatum is native in temperate North America. The temperate Asian L. japonicum is naturalized throughout much of the southeastern United States. About twenty years ago, L. microphyllum was introduced into South Florida and is now naturalized in several counties. The present study documents differences among spores and their generation, development of sporophytes from the fertilized egg, and in flavonoid chemistry. Hybridization experiments showed a strong possibility for cross fertility between species. Experiments with prothallial development and differentiation revealed …


Pleiochaeta Soil Survey, M Sweetingham Jan 1984

Pleiochaeta Soil Survey, M Sweetingham

Experimental Summaries - Plant Research

1. Pleiochaeta soil survey - Moora District, March 1984. 2. Lupin root rot trials - 84A40, 84BA26, 84GE50, 84GE56, 84MO82, 85NO59, 84WH28. 3. Fungicides for Rhizoctonia patch control - 84E25, 84E28. 4. 83WH29 : Effect of rotation on wheat diseases. 5. Root disease in long term wheat-lupin rotation trials - 68E5, 79GE37, 80TS2, 81LG29, 82M26.


Summary Of Rhizobium Experiments, J G. Howieson Jan 1984

Summary Of Rhizobium Experiments, J G. Howieson

Experimental Summaries - Plant Research

The main emphasis for rhizobial work in 1984 was on the acid tolerance of medic Rhizobium. The experimental programme in the field was greatly expanded to include testing of some 160 isolates collected from Sardinia in May 1984. Broadacre sowings of acid tolerant strain WSM 419 were undertaken as a preliminary step to its commercial release in 1985. Glasshouse work in 1984 was dedicated to a more intensive investigation of the factors contributing to the enhanced nodulating ability of M. polymorpha and M. murex on acid soils. As well, a simple technique for identifying acid tolerant strains of rhizobia in …


Environmental, Nutritional, And Physiological Factors Associated With Hoof Growth And Wear In Holstein Cows, Lisa Hartson Bemis Jan 1984

Environmental, Nutritional, And Physiological Factors Associated With Hoof Growth And Wear In Holstein Cows, Lisa Hartson Bemis

Electronic Theses and Dissertations

Environmental, nutritional, and physiological parameters associated with hoof growth and wear were evaluated using data from 140 Holstein cows in five herds. Growth and wear of the dorsal and lateral regions of the front and rear outside claws were measured at approximately 2 mo intervals over a 14 mo period. Housing facilities varied from continuous confinement on concrete to confinement in dirt lots and included loafing sheds, free stall barns, and one comfort stall facility with rubber mats. Lateral hoof regions grew 24% faster than dorsal regions in the front and 20% faster in the rear hooves. Rear hooves grew …


Two Classes Of Camp Analogs Which Are Selective For The Two Different Camp-Binding Sites Of Type Ii Protein Kinase Demonstrate Synergism When Added Together To Intact Adipocytes, Stephen J. Beebe, Rob Holloway, Stephen R. Rannels, Jackie D. Corbin Jan 1984

Two Classes Of Camp Analogs Which Are Selective For The Two Different Camp-Binding Sites Of Type Ii Protein Kinase Demonstrate Synergism When Added Together To Intact Adipocytes, Stephen J. Beebe, Rob Holloway, Stephen R. Rannels, Jackie D. Corbin

Bioelectrics Publications

Twenty-five cyclic nucleotide analogs were tested individually to act as lipolytic agents and to activate adipocyte protein kinase. The lipolytic potency of individual analogs correlated better with their K(a) for protein kinase and their lipophilicity rather than with either parameters alone. Some of the most potent lipolytic analogs had high I50 values for the particulate low K(m) cAMP phosphodiesterase suggesting that their effect was not due to raising endogenous cAMP levels through inhibition of phosphodiesterase. The most potent lipolytic analogs contained a thio moiety at the C-8 or C-6 position. These analogs exhibited concave upward dose-response curves. At high concentrations …


Characterization Of The Lipopolysaccharides (Lps) From Four Transposon Generated Symbiotic Mutants Of Rhizobium Trifolii, Robert G. Shatters Jr. Jan 1984

Characterization Of The Lipopolysaccharides (Lps) From Four Transposon Generated Symbiotic Mutants Of Rhizobium Trifolii, Robert G. Shatters Jr.

Masters Theses

The LPSs from four symbiotic mutants of R. trifolii were isolated and characterized. The mutants were obtained from Dr. Barry Rolfe of The Australian National University. Three mutants have Tn5 insertions in the "nod" regions of the symbiotic plasmid. The fourth has a 30 kb deletion. This deletion includes the majority of the "nod" regions. All mutants fail to nodulate clover and fail to induce markedly curled root hairs, i.e. they are hac-nod-. The LPSs were purified as described by Carlson et al. 1978.7 The polysaccharide portion of the LPSs was purified by treating the LPSs in 1% HAc …


Comparison Of Surface Polysaccharides Of R. Leguminosarum Anu57 (Exo-1), R. Leg. Anu57(Pbr1an) (Nod+, Nif-), And R. Leg. Anu57(Pjb5j1) (Nod+, Nif-), Frank G. Hustmyer Jan 1984

Comparison Of Surface Polysaccharides Of R. Leguminosarum Anu57 (Exo-1), R. Leg. Anu57(Pbr1an) (Nod+, Nif-), And R. Leg. Anu57(Pjb5j1) (Nod+, Nif-), Frank G. Hustmyer

Masters Theses

Extracellular polysaccharides (EPS) and lipopolysaccharides (LPS) are suspected to be involved in the legume/Rhizobium symbiotic process. Polysaccharide compositions from the EPS, LPS, capsular polysaccharide (CPS), and small polysaccharide (SmPS) were compared between Rhizobium leguminosarum ANU57 (parent, Exo-1) and two mutants R. leg. ANU57(pBR1AN) (nod+, nif-) and R. leg. ANU57(pJB5J1) (nod+, nif-) both containing a Sym (symbiotic) plasmid insertion. R. leg. ANU57(pBR1AN) and R. leg. ANU57(pJB5J1) are nod+ on clover and peas, respectively. The nod+ mutants produce larger amounts of EPS and decreased amounts of LPS compared to …


Ultrastructure Of Wheat (Triticum Aestivum) Leaf Cells Infected With Leaf Rust (Puccinia Recondita), And Wheat Streak Mosaic Virus, Saleh H. Shrief Jan 1984

Ultrastructure Of Wheat (Triticum Aestivum) Leaf Cells Infected With Leaf Rust (Puccinia Recondita), And Wheat Streak Mosaic Virus, Saleh H. Shrief

Electronic Theses and Dissertations

Puccinia recondita ultrastructure resembles that of other rust species. The urediospore infection was characterized by the formation of a specialized structure, the haustorium, within the leaf cells. The haustorium contains organelles such as nuclei, mitochondria, microbodies, ribosomes, lipid bodies, and vacuoles. A haustorial neck connects the haustorium with the haustorial mother cell, and contains a neck band made up of darkly stained material. The neck band was located at the last one third of its length toward the haustorium. The haustorial mother cell was situated intercellularly, and closely adhering to the cell wall, but contained few organelles, and the nucleus …


Louisiana Agriculture Magazine, Winter 1984-1985, Lsu Agricultural Experiment Station Jan 1984

Louisiana Agriculture Magazine, Winter 1984-1985, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.


Activation Of B Lymphocytes By Monovalent Anti-Lyb-2 Antibodies, Subbarao Bondada, D. E. Mosier Jan 1984

Activation Of B Lymphocytes By Monovalent Anti-Lyb-2 Antibodies, Subbarao Bondada, D. E. Mosier

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Small resting B lymphocytes are activated when their cell surface immuno-globulin (Ig) receptors interact with specific antigen or anti-Ig antibodies. Such a receptor-ligand interaction leads to enlargement and proliferation of B lymphocytes. These activated B cells can subsequently mature into Ig-secreting cells in the presence of appropriate accessory cell signals (1-3). However, monovalent anti-Ig antibodies cannot induce B cell activation even though they can bind to the surface Ig (4-7). It has thus been concluded that membrane Ig has to be cross-linked to induce early steps in B cell activation (membrane depolarization; 8) as well as later steps (proliferation). T …


In Vitro Testosterone Secretion By Testicular Tissue From Young Bulls And The Effects Of Chronic And Acute Exposure To Estradiol- 17Β, M. J. D'Occhio, B. D. Schanbacher, J. E. Kinder Jan 1984

In Vitro Testosterone Secretion By Testicular Tissue From Young Bulls And The Effects Of Chronic And Acute Exposure To Estradiol- 17Β, M. J. D'Occhio, B. D. Schanbacher, J. E. Kinder

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The possibility that estradiol-17/3 may directly influence testicular steroidogenesis in bulls was investigated in vitro. Testicular tissues were incubated for 4 h and regression coefficients (b, ng·ml-1·h-1) based on the increase in testosterone in the medium were used to describe testosterone secretion rates. In the first experiment, testicular tissues from control bulls and bulls chronically implanted with estradiol were incubated in the absence (basal conditions) or presence of 10 mlU/ml human chorionic gonadotropin (hCG). Under basal conditions, testosterone secretion rates were similar for tissues from control (b = 24.1 ± 6.0) and implanted (b = 34.7 …


Determination Of An Enzyme Deficiency In The Saccharomyces Cerevisiae Mutant Mod5-1, Lacking Isopentenylated Trnas, Sopiah Suid Jan 1984

Determination Of An Enzyme Deficiency In The Saccharomyces Cerevisiae Mutant Mod5-1, Lacking Isopentenylated Trnas, Sopiah Suid

Master's Theses

No abstract provided.


Development Of A Dna Probe For The Rapid Detection Of Cytomegalovirus, Nell Lurain Jan 1984

Development Of A Dna Probe For The Rapid Detection Of Cytomegalovirus, Nell Lurain

Master's Theses

No abstract provided.


Extracellular Phosphodiesterase From The Growth Medium Of The Myxomycete Physarum Flavicomum, Thomas J. Lynch, Mary E. Farrell Jan 1984

Extracellular Phosphodiesterase From The Growth Medium Of The Myxomycete Physarum Flavicomum, Thomas J. Lynch, Mary E. Farrell

Journal of the Arkansas Academy of Science

The plasmodium of the myxomycete Physarum flavicomum secretes cyclic AMP phosphodiesterase into the medium. The extracellular enzyme had a pH optimum between 7 and 8 and a Km of about 500 μM cyclic AMP and was inhibited by theophylline, caffeine and 3-isobutyl-l-methyxanthine (MIX). A marked decrease of enzyme activity was noted in the presence of EDTA, suggesting the requirement of Mg+ + by the enzyme. Addition of Mg+ + and Ca + + stimulated the enzyme while Zn+ + , Co+ + , Pb+ + , Mn+ + , Fe + + + , Ni+ + , and Cu + …


Setchenov Parameters For Naphthalene, Gerardo Gold Bouchot Jan 1984

Setchenov Parameters For Naphthalene, Gerardo Gold Bouchot

University of the Pacific Theses and Dissertations

It is the purpose of this work to study the solubility of naphthalene, the simplest polycyclic aromatic hydrocarbon as a function of the salt content and the temperature, in ranges that span those likely to be found in natural ecosystems. Another goal is to set up a high-pressure generator, to study the effect of pressure on the solubility of hydrocarbons.


Evaluation Of Peptide Assimilation In Ehrlich Ascites Tumor Cells, John M. Castellano Jan 1984

Evaluation Of Peptide Assimilation In Ehrlich Ascites Tumor Cells, John M. Castellano

Biological Sciences Theses & Dissertations

The dipeptides glycyl-L-(3H)-leucine and L-phenylalanyl-L-(3H)-leucine were synthesized in radioactive form and utilized in the analysis of peptide transport and hydrolysis by Ehrlich ascites tumor cells. The tumor cells were cultured in the abdominal cavity of CF-1 albino mice and harvested into sterile isotonic buffer for all experimental analyses.

The results of this study reveal that the tumor cells rapidly accumulate radiolabel when incubated with the above mentioned peptides, but that the peptide is most probably hydrolyzed extracellularly and free L-(3)-leucine transported. This hypothesis is based on the observations of reduction in accumulation of radiolabel …


Pharmacognosy Of The Saururaceae : Microscopy Of Powdered Drugs, Prakash Vaman Mallya Jan 1984

Pharmacognosy Of The Saururaceae : Microscopy Of Powdered Drugs, Prakash Vaman Mallya

University of the Pacific Theses and Dissertations

Plants of the family Sauruaceae are used in folk medicine in various parts of the world. Chemistry of some plants of this family and their chemotaxonomy has been investigated in our laboratory (12).

It is very difficult to establish identity and authenticity of commercially available crude drugs and powders of the Saururaceae because a detailed, collective study of microscopic features of these plants is not available. Original papers establishing plants of this family (see later) do not include microscopic features; they describe only gross morphologic and other classical features required for systematics. They are not useful for a pharmacologist in …


The Isolation And Identification Of Legionella Species From Environmental Sites In Rowan County, Kentucky, Sabo E. Yakubu Dec 1983

The Isolation And Identification Of Legionella Species From Environmental Sites In Rowan County, Kentucky, Sabo E. Yakubu

Morehead State Theses and Dissertations

A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Sabo E. Yakubu on December 17, 1983.


Bone Disease In Uremia, Jack W. Coburn Dec 1983

Bone Disease In Uremia, Jack W. Coburn

Henry Ford Hospital Medical Journal

No abstract provided.


Histopathology In Rat Temporal Bones Resulting From Excess Dietary Fluoride In Conjunction With Suspected Water Born Toxins, Donna Lee Healy Dec 1983

Histopathology In Rat Temporal Bones Resulting From Excess Dietary Fluoride In Conjunction With Suspected Water Born Toxins, Donna Lee Healy

Masters Theses

The occurrence of perinatal deaths, bony extoses, and deafness in dog kennels in certain areas of Michigan led The Upjohn Company and Western Michigan University to suspect fluoride toxicity and/or water born toxins. The present project was designed to examine the ability of excess fluoride ingestion and/or the ability of suspected water born toxins to induce histopathology in Sprague-Dawley rats. An otopathological assessment of the rat temporal bones showed no otopathology nor any changes in cochlear dimensions, however, a quantitative assessment of osteoclastic density showed a large increase in the numbers of osteoclasts of spongy bone in the high fluoride …


Isolation Of A Bacterium Capable Of Degrading Peanut Hull Lignin, Thomas J. Kerr, Robert D. Kerr, Ronald Benner Nov 1983

Isolation Of A Bacterium Capable Of Degrading Peanut Hull Lignin, Thomas J. Kerr, Robert D. Kerr, Ronald Benner

Faculty Publications

No abstract provided.


Louisiana Agriculture Magazine, Fall 1983, Lsu Agricultural Experiment Station Oct 1983

Louisiana Agriculture Magazine, Fall 1983, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.


Structural Bird Control - An Overview, Charles W. Areson Sep 1983

Structural Bird Control - An Overview, Charles W. Areson

Wildlife Damage Management Conference

Structural pest bird control is probably the most environmentally sensitive area of all pest control. The potential hazards associated with bird control are far greater and far more open to public scrutiny than in any other type of pest control. One error in judgment may bring the wrath of an entire community on you, as well as involve you with legal repercussions from both federal and state agencies. Hazards to non-target species are always a threat when using any type of program with toxics, and potential secondary hazards to protected and endangered species must always be considered. There is no …


Wildlife Damage Control: A Current Perspective, Jack H. Berryman Sep 1983

Wildlife Damage Control: A Current Perspective, Jack H. Berryman

Wildlife Damage Management Conference

I attach special importance to this responsibility and appreciate the opportunity to deliver these keynote comments. We are here to discuss a very important and always controversial subject. The first Eastern Wildlife Damage Control Conference provides a unique opportunity for all of us to constructively influence the future direction as well as the professional and public perception of this important wildlife management activity.