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The Relationship Of Hemolymph Sugar, Juvenile Hormone And Biogenic Amines To The Three Behavioral States Of Mature Honey Bees., Janko Bozic Jan 1996

The Relationship Of Hemolymph Sugar, Juvenile Hormone And Biogenic Amines To The Three Behavioral States Of Mature Honey Bees., Janko Bozic

LSU Historical Dissertations and Theses

Differences in sugar titers, JH synthesis rate and biogenic amine metabolism correlated with three distinct activity groups or mature bees: resting bees, followers and dancers. Dancers had lower trehalose titers than followers or resting bees. In absconding bees trehalose titers were even lower, due to greatly elevated locomotor activity. The collecting and transferring of food by dancers and followers resulted in a higher glucose titer than in resting bees. Followers had a higher-JH synthesis rate than dancers, suggesting that JH could be an internal motivational stimulus to recruit followers to forage. Dancers and followers collect and transfer food and therefore …

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The Biology And Ecology Of The Yellowmargined Leaf Beetle, Microtheca Ochroloma Stal, (Coleoptera: Chrysomelidae) On Crucifers., Abdullahi Olod Ameen Jan 1996

The Biology And Ecology Of The Yellowmargined Leaf Beetle, Microtheca Ochroloma Stal, (Coleoptera: Chrysomelidae) On Crucifers., Abdullahi Olod Ameen

LSU Historical Dissertations and Theses

The biology and ecology of the yellowmargined leaf beetle, Microtheca ochroloma Stal, were studied on cabbage, Brassica oleracea var capitata L., collard, B. oleracea var acephala L., mustard, B. juncea Cosson, turnip, B. rapa L., and radish, Raphanus sativus L. The life cycle of the beetle consists of an egg stage, four larval instars, prepupal, pupal and adult stages. There were no significant differences in the effect of host plant on duration of development of immature beetles (p = 0.3353). The mean duration of development from oviposition to adult emergence ranged from 26.6 d on turnip to 27.5 d on …

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Effects Of 5-Fiuorouracil On Escherichia Coli Ribosomes., Susan Pelei Belleh Nov 1995

Effects Of 5-Fiuorouracil On Escherichia Coli Ribosomes., Susan Pelei Belleh

Student Work

5-Fluorouracil (FUra), a chemotherapeutic agent, affects the growth of several kinds of tumor cells. It is known to affect DNA as well as RNA. Using Escherichia coli, this study has shown that FUra interferes with the synthesis and assembly of ribosomes. Cells treated in FUra concentrations between 25 ug/ml and 50 ug/ml gave severely retarded growth rates. Sucrose density gradient absorbance profiles of ribosomes from FUra-treated cells indicated altered structural and functional properties. These profiles showed large pools of free ribosomal subunits and few completely associated ribosomes or polyribosomes. The 23S rRNA from FUra-treated ribosomes showed an increases amount of …

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Cells Are Not Just Bags Of Water: A Personal Appreciation Of The Work Of Dr. Brij L. Gupta And His Contribution To Biological X-Ray Microanalysis, Alice Warley Aug 1995

Cells Are Not Just Bags Of Water: A Personal Appreciation Of The Work Of Dr. Brij L. Gupta And His Contribution To Biological X-Ray Microanalysis, Alice Warley

Scanning Microscopy

This paper surveys the contribution made by the work of Dr. B.L. Gupta to the science of biological X-ray microanalysis. A brief biographical sketch of Brij's early years is given, this is followed by considerations about the models for water transport across epithelia. The ultrastructural and histochemical studies carried out by Brij Gupta and colleagues are reviewed to introduce the historical need for the use of EPXMA for the study of ion and water transport in epithelia. The outstanding contribution made by Brij Gupta's work in this field is outlined, and his understanding of the subcellular distribution ions in other …

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The Identification And Characterization Of Protein Tyrosine Phosphatases Expressed In The Developing Rat Brain, Mustafa Sahin May 1995

The Identification And Characterization Of Protein Tyrosine Phosphatases Expressed In The Developing Rat Brain, Mustafa Sahin

Yale Medicine Thesis Digital Library

Previous studies of the developing nervous system have shown that cell-cell and cell-matrix interactions are involved in a variety of processes such as the proliferation, migration and differentiation of neurons. While many cell surface molecules have been identified, the signal transduction mechanisms through which they alter cellular responses are poorly understood. Recent studies have described a new and large family of enzymes, protein tyrosine phosphatases (PTPases), that may play a key role in transduction of cell surface events. Opposing the actions of protein tyrosine kinases (PTKs), PTPases may determine the state of tyrosine phosphorylation of a protein and regulate its …

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Community Metabolism And Nutrient Cycling In The Mississippi River Plume: Evidence For Intense Nitrification At Intermediate Salinities, Joseph D. Pakulski, Ronald Benner, Rainer Amon, Brian Eadie, Terry Whitledge Feb 1995

Community Metabolism And Nutrient Cycling In The Mississippi River Plume: Evidence For Intense Nitrification At Intermediate Salinities, Joseph D. Pakulski, Ronald Benner, Rainer Amon, Brian Eadie, Terry Whitledge

Faculty Publications

Community respiration, net nutrient fluxes and heterotrophic bacterial production were investigated in the Mississippi River (USA) plume during May 1992 using dark bottle incubations of unfiltered water. Highest rates of community O2 consumption and dissolved inorganic carbon regeneration were observed at intermediate (10 to 27%0) plume salinities. Plume surface 02 consumption rates were 2- to 4-fold greater than rates reported previously during the summer and winter. Heterotrophic bacterial production ([3H]-leucine incorporation) was also highest at intermediate salinities and 2- to 4-fold greater than rates reported from other seasons. Net regeneration of NH4+ …

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The Function Of Sarcoplasmic Reticulum In The Aged Rat Heart, Ming Tao Jiang Jan 1995

The Function Of Sarcoplasmic Reticulum In The Aged Rat Heart, Ming Tao Jiang

Digitized Theses

The purpose of this project was to study the effect of aging on the regulation of Ca{dollar}\sp{lcub}2+{rcub}{dollar} by cardiac sarcoplasmic reticulum (SR) and its potential contribution to the age-related alterations in myocardial contractile performance in Fischer 344 rats.;In cardiac membranes enriched in SR (MSR) and its light (LSR) and heavy (HSR) subfractions fractionated by a sucrose density gradient, the rate of ATP-supported and oxalate-facilitated Ca{dollar}\sp{lcub}2+{rcub}{dollar} uptake was significantly reduced (24-50%) in the aged (26-30 months old) compared with that of the adult rats (6-8 months old). With aging, the Ca{dollar}\sp{lcub}2+{rcub}{dollar}-stimulated phosphoenzyme of the Ca{dollar}\sp{lcub}2+{rcub}{dollar} pumps was reduced in MSR, LSR …

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Neurotransmission Of Visceral Information In The Parabrachial Nucleus Of The Rat, Tarek Saleh Jan 1995

Neurotransmission Of Visceral Information In The Parabrachial Nucleus Of The Rat, Tarek Saleh

Digitized Theses

The parabrachial nucleus (PB) has been shown to be a major relay site for visceral afferents ascending through the ventrobasal thalamus and terminating in the insular cortex. The purpose of these investigations was to determine the neurotransmitter mechanisms in the PB involved in relaying visceral sensory information to the thalamus in the rat. Using electrophysiological techniques in the cloral hydrate anesthetised male Wistar rat, our results show that the visceral pathway from the PB to the thalamus appears to use two neuronal systems, one mediating the relay of specific visceral information via glutamatergic N-methyl D-aspartate (NMDA) receptors in the PB, …

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The Interaction Of Thyroid Stimulating Hormone (Tsh), Insulin-Like Growth Factors (Igfs), And Insulin-Like Growth Factor Binding Proteins (Igfpbs) In The Regulation Of The Synthesis And Secretion Of Thyroid Hormones By Cultured Sheep Thyroid Cells, Jia Fang Wang Jan 1995

The Interaction Of Thyroid Stimulating Hormone (Tsh), Insulin-Like Growth Factors (Igfs), And Insulin-Like Growth Factor Binding Proteins (Igfpbs) In The Regulation Of The Synthesis And Secretion Of Thyroid Hormones By Cultured Sheep Thyroid Cells, Jia Fang Wang

Digitized Theses

Thyroid growth and function are regulated by TSH in synergy with other hormones, growth factors, and neurotransmitters. Insulin-like growth factors (IGFs), which have insulin-like effects on metabolism and regulate cell growth and function, are synthesized and secreted by thyroid cells. IGFs are associated with their specific binding proteins (IGFBPs), which not only carry and store IGFs in body fluids but also modulate the biological function of IGFs. Previous studies found that both IGFs and IGFBPs participated in the regulation of the growth of thyroid cells.;This study has further examined the biological function of IGFs and IGFBPs in the regulation of …

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The Putative Role Of Fatty Acids In The Activation Of Trehalose Synthesis In The Fat Body Of The Cockroach Periplaneta Americana L, Irshad Ali Jan 1995

The Putative Role Of Fatty Acids In The Activation Of Trehalose Synthesis In The Fat Body Of The Cockroach Periplaneta Americana L, Irshad Ali

Digitized Theses

Hypertrehalosemic hormones produced by the corpus cardiacum increase the concentration of several fatty acids in cockroach fat body trophocytes. The phospholipase A{dollar}\sb2{dollar} (PLA{dollar}\sb2){dollar} activator melittin has a similar effect. The fatty acids include palmitic, stearic, oleic and linoleic acid. The hormone mediated release of these fatty acids is blocked by the PLA{dollar}\sb2{dollar} inhibitors mepacrine and {dollar}\rho{dollar}-bromophenacyl bromide. These observations suggest that hormonal release of fatty acids, may be due to the activation of PLA{dollar}\sb2.{dollar};The increase in non-esterified fatty acids appears to be linked to the increase in trehalose efflux since sugar efflux is stimulated by stearic, oleic, linoleic and arachidonic …

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Mechanisms Of Autonomic Control By The Insular Cortex In The Rat, Kenneth Scott Butcher Jan 1995

Mechanisms Of Autonomic Control By The Insular Cortex In The Rat, Kenneth Scott Butcher

Digitized Theses

The insular cortex (IC) has been proposed to act as visceral sensory and autonomic cortex. The mechanism of control by the IC, however, is not clear. The nature of insular cortical function in hypertension is also unknown.;Middle cerebral artery occlusion (MCAO) in Wistar rats has been shown to cause cortical infarction, including the IC, resulting in increases in sympathetic nerve discharge (SND). MCAO in the urethane anesthetized spontaneously hypertensive rat (SHR) resulted in decreases in arterial pressure (AP) and SND.;To determine if the autonomic effects of MCAO in the SHR and Wistar rat are due to insular damage, a lesion …

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Characterization Of Fungal Fimbriae, Martina Celerin Jan 1995

Characterization Of Fungal Fimbriae, Martina Celerin

Digitized Theses

Fungal fimbriae are surface appendages that were first described by Poon and Day (1974) on the haploid cells of Microbotryum violaceum. They are long (1 to 20 {dollar}\mu{dollar}m), narrow (7 nm) flexuous fibres that were implicated in important cellular functions such as mating and pathogenesis. Since this initial description, numerous other fungi from all five phyla have been shown to produce fimbriae on their extracellular surfaces. Because they are easy to purify, the fimbriae from M. violaceum have been investigated most extensively. The present study extends the earlier characterizations of M. violaceum fimbriae, and expands on the biochemical description of …

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Epidermal Growth Factor Regulation Of Porcine Oocyte Maturation And Cumulus Cell Expansion In Vitro, Balwant Singh Jan 1995

Epidermal Growth Factor Regulation Of Porcine Oocyte Maturation And Cumulus Cell Expansion In Vitro, Balwant Singh

Digitized Theses

The overall objective of this study was to investigate the role in vitro of epidermal growth factor (EGF) in the regulation of both nuclear and cytoplasmic maturation of the porcine oocyte, and in the expansion of cumulus cells.;Studies aimed at the induction of oocyte maturation and cumulus expansion revealed that EGF is a potent stimulant of the resumption of meiosis in the oocyte and that the addition of FSH, but not LH, to EGF further enhances its effect on germinal vesicle breakdown (GVBD). Both estradiol-17{dollar}\beta{dollar} (E{dollar}\sb2{dollar}) and androstenedione (A{dollar}\sb4{dollar}) inhibited FSH-stimulated GVBD, but had no effect on EGF-stimulated GVBD, suggesting …

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Feedback Control Mechanisms Regulating Breathing In Humans, Croix Claudette St Jan 1995

Feedback Control Mechanisms Regulating Breathing In Humans, Croix Claudette St

Digitized Theses

The respiratory system regulates alveolar ventilation (V{dollar}\sb{lcub}\rm A{rcub}{dollar}) almost exactly to the demands of the body so that the PCO{dollar}\sb2{dollar} and PO{dollar}\sb2{dollar} of the arterial blood are hardly altered, even during strenuous exercise or other types of respiratory stress. The feedback control of ventilation was studied in human subjects using the technique of dynamic end-tidal forcings to produce perturbations in end-tidal PCO{dollar}\sb2{dollar} (P{dollar}\sb{lcub}\rm ET{rcub}{dollar}CO{dollar}\sb2{dollar}) and end-tidal PO{dollar}\sb2{dollar} (P{dollar}\sb{lcub}\rm ET{rcub}{dollar}O{dollar}\sb2{dollar}) to stimulate the respiratory chemoreceptors.;The purpose of the first study was to investigate the interaction between ventilatory drives from the central (cR{dollar}\sb{lcub}\rm c{rcub}{dollar}) and peripheral (pR{dollar}\sb{lcub}\rm c{rcub}{dollar}) chemoreceptors using their different …

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A Proposed Acrosomal System For Identifying Stages Of The Cycle Of The Seminiferous Epithelium And A Model For The Kinetics Of Spermatogenesis In The Rabbit, Antonio Carlos S Castro Jan 1995

A Proposed Acrosomal System For Identifying Stages Of The Cycle Of The Seminiferous Epithelium And A Model For The Kinetics Of Spermatogenesis In The Rabbit, Antonio Carlos S Castro

Doctoral Dissertations

Most quantitative investigations of spermatogenesis requites identification of stages of the cycle of the seminiferous epithelium. The current "tubular morphology" system of staging for the rabbit permits identification of only eight stages and is not applicable to all experimental conditions. A more advantageous staging system, based on changes in the acrosome and morphology of the developing spermatids, had not been developed for the rabbit. Knowledge of spermatogonial kinetics, including the identity of spermatogonial subtypes and the number and timing of spermatogonial divisions, is also important, but had not been fully elucidated in this species. This investigation was undertaken to develop …

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Functional Anatomy Of The Integument And Subcutaneous Structures Of The Head, Neck And Thorax Of The Domestic Turkey, Meleagris Gallopavo., Kumudini Nishantha De Silva Jan 1995

Functional Anatomy Of The Integument And Subcutaneous Structures Of The Head, Neck And Thorax Of The Domestic Turkey, Meleagris Gallopavo., Kumudini Nishantha De Silva

LSU Historical Dissertations and Theses

The microdissection of the integument and subcutaneous structures of the head, neck, and thorax of the Domestic Turkey, Meleagris gallopavo, revealed a complex system with several distinct layers of connective tissue, smooth and striated musculature, and fat bodies (corpora adiposa). These layers show structural variations across the body surface, and the patterns of variation of the different layers correlate with one another. The smooth apterial muscles and the striated subcutaneous muscles complement each other in moving certain feather tracts. Fat tissue is deposited in the dermis as dermal fat, in the Fascia superficialis, and in distinct fat bodies associated with …

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Biogeographic, Ecological, And Evolutionary Aspects Of South American Austral Migration, With Special Reference To The Family Tyrannidae., Robert Terry Chesser Jan 1995

Biogeographic, Ecological, And Evolutionary Aspects Of South American Austral Migration, With Special Reference To The Family Tyrannidae., Robert Terry Chesser

LSU Historical Dissertations and Theses

South American austral migrants are bird species that breed in temperate South America in the southern summer and migrate north, towards or into northern South America, for the southern winter. Austral migration is similar to other avian migration systems in many ways, but its uniquely South American locale is reflected geographically by the relatively short-distance migrations of most austral migrants, and taxonomically by the numerical dominance of the suboscine family Tyrannidae (the tyrant-flycatchers), of which more than 70 species migrate. Detailed examination of the distributions of austral migrant flycatchers revealed that each is to some extent unique, but that discernible …

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Scientific Discipline And The Origins Of Race: A Foucaultian Reading Of The History Of Biology, Ladelle Mcwhorter Jan 1995

Scientific Discipline And The Origins Of Race: A Foucaultian Reading Of The History Of Biology, Ladelle Mcwhorter

Philosophy Faculty Publications

Foucault's "power-knowledge" is a controversial concept. Brought into English-speaking theoretical circles less than two decades ago, its meaning and range of applicability are still in dispute. While no one denies that some fields of social scientific knowledge (such as criminology) intersect institutionally with mechanisms of power, these intersections do not seem, to many, to constitute any essential relation of "mutual reinforcement" between knowledge and power. If, in rare cases, politics and scientific research are admitted to be mutually constitutive, the results of their mingling are typically dismissed as propaganda or pseudo-science. A few thinkers are willing to allow the entirety …

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Daily Variations In Protein Synthesis And Tissue Responsiveness To Growth Hormone, Prolactin And Insulin-Like Growth Factor-I In The Gulf Killifish, Fundulus Grandis Baird And Girard., Zeleke Negatu Jan 1995

Daily Variations In Protein Synthesis And Tissue Responsiveness To Growth Hormone, Prolactin And Insulin-Like Growth Factor-I In The Gulf Killifish, Fundulus Grandis Baird And Girard., Zeleke Negatu

LSU Historical Dissertations and Theses

Circadian variations of $\sp{14}$C-glycine incorporation into protein and the responsiveness of muscle tissue to growth hormone, prolactin and insulin-like growth factor-I were examined in gulf killifish, Fundulus grandis. Incorporation of label during a 5 h period following $\sp{14}$C-glycine injection was tested at different times of day (LD 12:12). Incorporation varied during the day in all the tissues examined (scale, muscle, liver and intestine). The times of peak incorporations differed among the tissues. Scales showed peak incorporation during the dark hours. Peak incorporation by muscle occurred at the onset of light. These patterns were similar in male and female fish. The …

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The Habitat, Ecology And Epidemiology Of Eastern Equine Encephalomyelitis In Southeast Louisiana., Kenny L. Samui Jan 1995

The Habitat, Ecology And Epidemiology Of Eastern Equine Encephalomyelitis In Southeast Louisiana., Kenny L. Samui

LSU Historical Dissertations and Theses

Many unanswered questions on the epidemiology and ecology of eastern equine encephalomyelitis (EEE) still preclude a complete understanding of its natural history. Among these are the distribution and epidemic vectors of EEE virus (EEEV) in different regions, habitats, and foci; its inter-epidemic maintenance, and overwintering mechanisms. Phase 1 of a research project designed to find answers to the above questions with regard to southeast Louisiana was conducted over 1992 and 1993, and consisted of several individual studies. These included 3 mosquito studies to determine major horse- and bird-feeding mosquito species that could be the EEEV epidemic vectors in southeast Louisiana; …

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Cloning, Expression, Primary Structure, And Insertion Mutagenesis Of The Pyruvate Formate-Lyase Enzyme Of Aeromonas Hydrophila., Mohamed Alaa Eldin Abdelalim Awad Jan 1995

Cloning, Expression, Primary Structure, And Insertion Mutagenesis Of The Pyruvate Formate-Lyase Enzyme Of Aeromonas Hydrophila., Mohamed Alaa Eldin Abdelalim Awad

LSU Historical Dissertations and Theses

The pyruvate formate-lyase enzyme (Pfl), a key enzyme in alcoholic fermentation, catalyzes the anaerobic conversion of pyruvate into acetyl-CoA and formate in prokaryotes. The pyruvate formate-lyase gene (pfl) of the facultative anaerobe Aeromonas hydrophila was cloned and sequenced. Subsequently, the Pfl was characterized based on the deduced amino acid sequence and evaluated in vivo following insertion mutagenesis. Finally, the pathogenesis of a defined mutant was compared to wild type A. hydrophila in channel catfish. The pfl of A. hydrophila was identified from two recombinant pBluescript SK(-) clones excised from a $\lambda$ ZAP II phage library. Both clones carried the same …

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Molecular Cloning, Sequencing, And Regulation Of The Rhodobacter Capsulatushemb Gene., Karl Joseph Indest Jan 1995

Molecular Cloning, Sequencing, And Regulation Of The Rhodobacter Capsulatushemb Gene., Karl Joseph Indest

LSU Historical Dissertations and Theses

The common tetrapyrrole pathway in the photosynthetic bacterium, Rhodobacter capsulatus, is responsible for the synthesis of bacteriochlorophyll, heme, vitamin B-12, and siroheme. The common portion of this pathway is regulated up to 100-fold by changes in oxygen tension. This regulation is accomplished by controlling the intracellular level of porphobilinogen. One way in which porphobilinogen levels could be controlled is by regulating the synthesis of porphobilinogen. Porphobilinogen synthase, encoded by the hemB gene, is the second enzyme in the common tetrapyrrole pathway that catalyzes the dimerization of 5-aminolevulinic acid to form the monopyrrole porphobilinogen. In order to further investigate the mechanism …

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Transcriptional Studies Of The Muscle-Specific Expression Of The Rabbit Muscle Phosphofructokinase Gene., Haiqing Fu Schiltz Jan 1995

Transcriptional Studies Of The Muscle-Specific Expression Of The Rabbit Muscle Phosphofructokinase Gene., Haiqing Fu Schiltz

LSU Historical Dissertations and Theses

The rabbit muscle phosphofructokinase (RM-PFK) gene is predominantly expressed in skeletal muscle. Its muscle-specific transcription was investigated using transient transfection studies, electrophoretic mobility shift assays, and DNaseI footprinting experiments. The evidence presented here provides the first example of the myogenic basic-Helix-Loop-Helix proteins regulating a gene that encodes a glycolytic enzyme. The 3 kb 5$\sp\prime$-flanking sequence of this gene directed the expression of the chloramphenicol acetyltransferase gene in muscle and non-muscle cells. MyoD, Myf5, and myogenin exhibited differential transactivation capabilities. MyoD had the most pronounced transactivational effect, and its N-terminal transactivation domain and the basic DNA-binding region were required for its …

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The Rabbit Muscle Phosphofructokinase Gene: Six Types Ofmrnas Are Tissue-Specifically Expressed By Multiple Promoters And Alternative Splicing., Shouhua Xiao Jan 1995

The Rabbit Muscle Phosphofructokinase Gene: Six Types Ofmrnas Are Tissue-Specifically Expressed By Multiple Promoters And Alternative Splicing., Shouhua Xiao

LSU Historical Dissertations and Theses

Phosphofructokinase (ATP:Fructose-6-phosphate 1-phospho-transferase, EC 2.7.1.11, PFK) catalyzes the phosphorylation of fructose 6-phosphate to generate fructose 1,6-bisphosphate, the rate-limiting step of glycolytic pathway. Li et al. (1990) have identified two cDNAs for the rabbit muscle PFK with an identical coding regions but different 5$\sp\prime$ untranslated regions (UTRs). In this dissertation research, six cDNAs for the rabbit muscle PFK mRNAs were cloned. These cDNAs are different in their 5$\sp\prime$ UTRs but have an identical open reading frame. The transcription initiation sites of two downstream promoters of this gene have been determined. A proximal promoter (Pa) is TATA-less and 86 bp upstream of …

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A Study Of Differences In Binding Of Hepatic Nuclear Proteins To The Upstream Region Of Glucocorticoid Regulated Tyrosine Aminotransferase Gene In Lean And Obese Rats., Huijun Dong Jan 1995

A Study Of Differences In Binding Of Hepatic Nuclear Proteins To The Upstream Region Of Glucocorticoid Regulated Tyrosine Aminotransferase Gene In Lean And Obese Rats., Huijun Dong

LSU Historical Dissertations and Theses

Glucocorticoids are required for the development of all forms of experimental obesity. Studies on Zucker fa/fa rats have revealed that the obese Zucker rat is hyper-responsive to the effects of glucocorticoids. This excessive response may result from an alteration in level or activity of a transcription factor in nuclei of obese fa/fa rat. Evidence from gel retardation assays using DNA fragments from the upstream region of glucocorticoid regulated tyrosine aminotransferase (TAT) gene and the nuclear extracts from obese and lean rats showed in this study that an increased amount of DNA fragment was shifted by nuclear extracts from obese rats …

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Effects Of Exogenous Female Sex Hormones On Food Intake, Macronutrients And Body Weight In The Ovariectomized Postbreeder Female Rat., Jan Barton Hamilton Jan 1995

Effects Of Exogenous Female Sex Hormones On Food Intake, Macronutrients And Body Weight In The Ovariectomized Postbreeder Female Rat., Jan Barton Hamilton

LSU Historical Dissertations and Theses

Hormone replacement therapy (HRT) is chosen by a growing segment of the postmenopausal population. Mid-life body weight gain is perceived to increase further with exogenous HRT. To examine hormonal effects on caloric intake (CI), carbohydrate (CHO), FAT, protein (PRO), chocolate and body weight (BW) in a female model, Sprague-Dawley postbreeder (n = 55) rats (10 mos., 10 litters of pups) were ovariectomized (OV) and implanted with 17 $\beta$ estradiol (E) and/or progesterone (P), or placebo in three separate studies (phases) of 10 days each. Uterine weights (p =.0001) and radioimmunoassay confirmed hormonal bioactivity. The sham (S) group with placebo implant …

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Biotic And Abiotic Factors That Affect The Development And Survival Of Cat Flea (Ctenocephalides Felis (Bouche)) Life Stages., William Joseph Lawrence Jr Jan 1995

Biotic And Abiotic Factors That Affect The Development And Survival Of Cat Flea (Ctenocephalides Felis (Bouche)) Life Stages., William Joseph Lawrence Jr

LSU Historical Dissertations and Theses

Biotic and abiotic factors that affect the development and survival of cat flea (Ctenocephalides felis (Bouche)) life stages were studied. Adult feas maintained on an artificial host system exhibited high rates of mortality when provided with dog hair substrates washed in either hexane or soap and water. Delayed egg production for fleas provided with bovine blood containing Na Citrate concentrations $>$8 mM was observed. Fleas fed with Na Citrate concentrations $\ge$24 mM had an increase in blood consumption and mortality. Certain concentrations of testosterone fed to fleas either in steer blood or in an alternate blood meal were associated …

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Follicular Development Patterns Of Pregnant Mares During The First Half Of Gestation., Marius Meintjes Jan 1995

Follicular Development Patterns Of Pregnant Mares During The First Half Of Gestation., Marius Meintjes

LSU Historical Dissertations and Theses

Information gained by studying follicular wave and endocrinological patterns of pregnant mares, may be useful in understanding reproductive wastage, infertility, control of the estrous cycle and physiological function of equine chorionic gonadotropin (eCG). Furthermore, supplementary follicular development, characteristic of the early equine pregnancy, may be used to harvest oocytes for gamete intrafallopian tube transfer and in vitro fertilization (IVF) procedures. The objectives of this study were to: characterize follicular wave patterns during the first half of the equine pregnancy; relate follicular development patterns to serum levels of estradiol-17$\beta$, progesterone, FSH and eCG; evaluate the effect of fetal genotype on follicular …

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Interleukin-2 Promoter/Enhancer Controlled Expression Of A Synthetic Cecropin-Class Lytic Peptide In Transgenic Mice., William Andrew Reed Jan 1995

Interleukin-2 Promoter/Enhancer Controlled Expression Of A Synthetic Cecropin-Class Lytic Peptide In Transgenic Mice., William Andrew Reed

LSU Historical Dissertations and Theses

Pathogens continue to evolve mechanisms of avoiding efforts to control their spread. Treatment with exogenous antimicrobials often occurs after the pathogen has reproduced extensively in the host. In the case of mammals, the immune system may not be fully mobilized for 72 h after the detection of foreign antigen. However, within 24 h of presentation of antigen by antigen-presenting cells to resting thymus-derived lymphocytes IL2 is produced. A class of broad spectrum antimicrobial peptides which constitute a major component of the insect immune system has been described and characterized. Called "cecropins", they are relatively non-toxic to normal cells from multicellular …

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Binding Of Hepatic Nuclear Proteins From Obese And Lean Zucker Rats To The Upstream Region Of Malic Enzyme Gene., Yibing Wang Jan 1995

Binding Of Hepatic Nuclear Proteins From Obese And Lean Zucker Rats To The Upstream Region Of Malic Enzyme Gene., Yibing Wang

LSU Historical Dissertations and Theses

Adrenal glucocorticoids are essential for the development of all forms of experimental obesity. In the obese (fa/fa) Zucker rats, adrenalectomy prevents the further development of obesity, and glucocorticoid replacement restores the obese phenotype. We have hypothesized that this dependence on glucocorticoids is due to differences in transcriptional regulation of a group of genes that are normally regulated by glucocorticoids. We have chosen to study the DNA fragments from the upstream region of the malic enzyme (ME) gene, which is positively regulated by glucocorticoids. Hepatic nuclear extracts from lean and obese Zucker rats were used in band shift studies to look …

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