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Site-Dependent Regulation Of Population Size: A New Synthesis, Nicholas L. Rodenhouse, Thomas W. Sherry, Richard T. Holmes Oct 1997

Site-Dependent Regulation Of Population Size: A New Synthesis, Nicholas L. Rodenhouse, Thomas W. Sherry, Richard T. Holmes

Dartmouth Scholarship

The nature and extent of population regulation remains a principal unanswered question for many types of organisms, despite extensive research. In this paper, we provide a new synthesis of theoretical and empirical evidence that elucidates and extends a mechanism of population regulation for species whose individuals preemptively use sites that differ in suitability. The sites may be territories, refuges from predation, oviposition sites, etc. The mechanism, which we call site dependence, is not an alternative to density dependence; rather, site dependence is one of several mechanisms that potentially generate the negative feedback required for regulation. Site dependence has two major …

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Expression Of Smooth Muscle Myosin Heavy Chains And Unloaded Shortening In Single Smooth Muscle Cells, Daniel P. Meer, Thomas J. Eddinger Oct 1997

Expression Of Smooth Muscle Myosin Heavy Chains And Unloaded Shortening In Single Smooth Muscle Cells, Daniel P. Meer, Thomas J. Eddinger

Biological Sciences Faculty Research and Publications

The functional significance of the variable expression of the smooth muscle myosin heavy chain (SM-MHC) tail isoforms, SM1 and SM2, was examined at the mRNA level (which correlates with the protein level) in individual permeabilized rabbit arterial smooth muscle cells (SMCs). The length of untethered single permeabilized SMCs was monitored during unloaded shortening in response to increased Ca2+ (pCa 6.0), histamine (1 μM), and phenylephrine (1 μM). Subsequent to contraction, the relative expression of SM1 and SM2 mRNAs from the same individual SMCs was determined by reverse transcription-polymerase chain reaction amplification and densitometric analysis. Correlational analyses between the SM2-to-SM1 …

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Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley Oct 1997

Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley

Faculty and Staff Publications – Milner Library

Conservation biology is a multidisciplinary subject of recent origins. Analysis of cited monographs from the journal Conservation Biology resulted in a list of 47 monographs which were heavily cited for this discipline. Over half of these were from related disciplines such as ecology, genetics, evolution, population biology, statistics, and natural resource management.

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Myelin-Associated Glycoprotein Interacts With Neurons Via A Sialic Acid Binding Site At Arg118 And A Distinct Neurite Inhibition Site, Song Tang, Ying Jing Shen, Maria Elena Debellard, Gitali Mukhopadhyay, James L. Salzer, Paul R. Crocker, Marie T. Filbin Sep 1997

Myelin-Associated Glycoprotein Interacts With Neurons Via A Sialic Acid Binding Site At Arg118 And A Distinct Neurite Inhibition Site, Song Tang, Ying Jing Shen, Maria Elena Debellard, Gitali Mukhopadhyay, James L. Salzer, Paul R. Crocker, Marie T. Filbin

Publications and Research

Inhibitory components in myelin are largely responsible for the lack of regeneration in the mammalian CNS. Myelin-associated glycoprotein (MAG), a sialic acid binding protein and a component of myelin, is a potent inhibitor of neurite outgrowth from a variety of neurons both in vitro and in vivo. Here, we show that MAG’s sialic acid binding site is distinct from its neurite inhibitory activity. Alone, sialic acid–dependent binding of MAG to neurons is insufficient to effect inhibition of axonal growth. Thus, while soluble MAG-Fc (MAG extracellular domain fused to Fc), a truncated form of MAG-Fc missing Ig-domains 4 and 5, MAG(d1-3)-Fc, …

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Draft: Optimising The Worth Of The Lobster Catch: Options And Issues, Marec Pty Ltd Sep 1997

Draft: Optimising The Worth Of The Lobster Catch: Options And Issues, Marec Pty Ltd

Fisheries Management Papers

The purpose of this document is to contribute to informed discussion on alternative measures which might be adopted to optimise the worth of the lobster catch. In doing so, it provides a number of possible initiatives which could be more closely examined for adoption. Details of issues are provided which should be taken into consideration when assessing the various proposals. The industry as it is today is examined and assessed, and its achievements analysed. The possible initiatives proposed stem from this research. As a consequence of this document, the rock lobster industry could undertake to proceed with a detailed examination …

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The Ccrm Dna Methyltransferase Is Widespread In The Alpha Subdivision Of Proteobacteria, And Its Essential Functions Are Conserved In Rhizobium Meliloti And Caulobacter Crescentus, Craig Stephens, Rachel Wright, Lucy Shapiro Sep 1997

The Ccrm Dna Methyltransferase Is Widespread In The Alpha Subdivision Of Proteobacteria, And Its Essential Functions Are Conserved In Rhizobium Meliloti And Caulobacter Crescentus, Craig Stephens, Rachel Wright, Lucy Shapiro

Biology

The Caulobacter crescentus DNA methyltransferase CcrM (M.CcrMI) methylates the adenine residue in the sequence GANTC. The CcrM DNA methyltransferase is essential for viability, but it does not appear to be part of a DNA restriction-modification system. CcrM homologs are widespread in the alpha subdivision of gram-negative bacteria. We have amplified and sequenced a 258-bp region of the cerM gene from several of these bacteria, including Rhizobium meliloti, Brucella abortus, Agrobacterium tumefaciens, and Rhodobacter capsulatus. Alignment of the deduced amino acid sequences revealed that these proteins constitute a highly conserved DNA methyltransferase family. Isolation of the full-length ccrM genes from the …

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Compounds Exuded By Phaseolus Vulgaris That Induce A Modification Of Rhizobium Etli Lipopolysaccharide, Dominik M. Duelli, K. Dale Noel Sep 1997

Compounds Exuded By Phaseolus Vulgaris That Induce A Modification Of Rhizobium Etli Lipopolysaccharide, Dominik M. Duelli, K. Dale Noel

Biological Sciences Faculty Research and Publications

Exudates released from germinating seeds and roots of a black-seeded bean (Phaseolus vulgaris cv. Midnight Black Turtle Soup) induce an antigenic change in the lipopolysaccharide (LPS) of Rhizobium etli CE3. By spectroscopic analyses and chromatographic comparisons with derived standards, the chemical structures of the aglycone portions of the major inducing molecules from seed exudate were deduced, and they were identified as delphinidin, cyanidin, petunidin, and malvidin. These anthocyanidins were present in seed exudate mainly as glycosides, the chief inducer being delphinidin 3-glucoside. Also present were 3-glucosides of petunidin and malvidin and glycosides of cyanidin and delphinidin. Seed exudate from …

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An Actin-Related Protein In Drosophila Colocalizes With Heterochromatin Protein 1 In Pericentric Heterochromatin, S Frankel, E Sigel, C Craig, Sarah C.R. Elgin, M Mooseker, S Artavanis-Tsakonas Sep 1997

An Actin-Related Protein In Drosophila Colocalizes With Heterochromatin Protein 1 In Pericentric Heterochromatin, S Frankel, E Sigel, C Craig, Sarah C.R. Elgin, M Mooseker, S Artavanis-Tsakonas

Biology Faculty Research

The actin-related proteins have been identified by virtue of their sequence similarity to actin. While their structures are thought to be closely homologous to actin, they exhibit a far greater range of functional diversity. We have localized the Drosophila actin-related protein, Arp4, to the nucleus. It is most abundant during embryogenesis but is expressed at all developmental stages. Within the nucleus Arp4 is primarily localized to the centric heterochromatin. Polytene chromosome spreads indicate it is also present at much lower levels in numerous euchromatic bands. The only other protein in Drosophila reported to be primarily localized to centric heterochromatin in …

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Detection Of Hybridization Events Between The Coyote, Canis Latrans, And The Domestic Dog, Canis Familiaris, Using Two Polymorphic Microsatellite Loci And Cranial Morphometric Analysis, John Jobe Cox Aug 1997

Detection Of Hybridization Events Between The Coyote, Canis Latrans, And The Domestic Dog, Canis Familiaris, Using Two Polymorphic Microsatellite Loci And Cranial Morphometric Analysis, John Jobe Cox

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by John Jobe Cox on August 26, 1997.

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Loss Of Matrix Adhesion Triggers Rapid Transformation-Selective Apoptosis In Fibroblasts, G. Mcgill, A. Shimamura, R. C. Bates, Robert E. Savage, D. E. Fisher Aug 1997

Loss Of Matrix Adhesion Triggers Rapid Transformation-Selective Apoptosis In Fibroblasts, G. Mcgill, A. Shimamura, R. C. Bates, Robert E. Savage, D. E. Fisher

Biology Faculty Works

Cell–matrix and cell–cell adhesion are recognized physiological determinants of cell growth and survival. In epithelial and endothelial cell systems, oncogenic transformation has in several cases been shown to confer resistance to apoptosis upon depriving cells of substrate adhesion. We examined the effects of oncogenic transformation in adherent versus adhesion- deprived primary embryonic fibroblasts. Whereas untransformed early passage fibroblasts undergo cell cycle arrest, their Myc/Ras- or E1A/Ras-transformed counterparts rapidly enter apoptosis when placed into suspension. This phenomenon also occurs upon incubation with a soluble, RGD-containing integrin ligand and is blocked by a peptide antagonist to ICE family proteases or by aggregation …

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Concentration-Dependent Patterning Of The Xenopus Ectoderm By Bmp4 And Its Signal Transducer Smad1, Paul A. Wilson, Giorgio Lagna, Atsushi Suzuki, Ali Hemmati-Brivanlou Aug 1997

Concentration-Dependent Patterning Of The Xenopus Ectoderm By Bmp4 And Its Signal Transducer Smad1, Paul A. Wilson, Giorgio Lagna, Atsushi Suzuki, Ali Hemmati-Brivanlou

Biology

Morphogens are thought to establish pattern in early embryos by specifying several cell fates along a gradient of concentration; a well-studied example is the Drosophila protein decapentaplegic (DPP) acting in the wing disc. Recent work has established that bone morphogenetic protein 4 (BMP4), the vertebrate homologue of DPP, controls the fundamental choice between neural and epidermal fates in the vertebrate ectoderm, under the control of antagonists secreted by the organizer region of the mesoderm. We now show that BMP4 can act as a morphogen, evoking distinct responses in Xenopus ecto-dermal cells at high and low concentrations, in a pattern consistent …

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Detection Of Functional Nicotinic Receptors Blocked By Α-Bungarotoxin On Pc12 Cells And Dependence Of Their Expression On Post-Translational Events, Edward M. Blumenthal, William G. Conroy, Suzanne J. Romano, Paul D. Kassner, Darwin K. Berg Aug 1997

Detection Of Functional Nicotinic Receptors Blocked By Α-Bungarotoxin On Pc12 Cells And Dependence Of Their Expression On Post-Translational Events, Edward M. Blumenthal, William G. Conroy, Suzanne J. Romano, Paul D. Kassner, Darwin K. Berg

Biological Sciences Faculty Research and Publications

A major class of nicotinic receptors in the nervous system is one that binds α-bungarotoxin and contains the α7 gene product. PC12 cells, frequently used to study nicotinic receptors, express the α7 gene and have binding sites for the toxin, but previous attempts to elicit currents from the putative receptors have failed. Using whole-cell patch-clamp recording techniques and rapid application of agonist, we find a rapidly desensitizing acetylcholine-induced current in the cells that can be blocked by α-bungarotoxin. The current amplitude varies dramatically among three populations of PC12 cells but correlates well with the number of toxin-binding receptors. In contrast, …

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Whole Body In Vitro Hydraulic Conductivity And Transcapillary Filtration In Two Amphibians, Bufo Marinus And Rana Catesbeiana, Thomas Vincent Hancock Aug 1997

Whole Body In Vitro Hydraulic Conductivity And Transcapillary Filtration In Two Amphibians, Bufo Marinus And Rana Catesbeiana, Thomas Vincent Hancock

Dissertations and Theses

The capillary filtration coefficient (CFC) and isovolumetric capillary pressure (Pci) were measured in Bufo marinus and Rana catesbeiana, using a gravimetric technique on an in vitro preparation while perfusing with Ringers and 0.1 g·100 ml-1 bovine serum albumin Estimates of pre- and post-capillary resistance were obtained from Bufo; the post- to pre-capillary resistance ratio was found to be 0.18, which was used to estimate capillary pressure. CFC was found to be 6.68 ± 0.51 and 5.07 ± 0.23 ml·min-1·kg-1·mmHg-1 and Pci was found to be 7.4 and 6.3 mmHg in …

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Isolation And Characterization Of Luxi And Luxr Homologues From Edwardsiella Ictaluri, Edward Todd Jacobs Aug 1997

Isolation And Characterization Of Luxi And Luxr Homologues From Edwardsiella Ictaluri, Edward Todd Jacobs

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Edward Todd Jacobs on August 1, 1997.

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Partial Characterization Of Na+, K+-Atpase And Its Gill And Antennal Gland Osmoregulatory Role In The Crayfish, Orconectes Putnami, Michael E. Fultz Aug 1997

Partial Characterization Of Na+, K+-Atpase And Its Gill And Antennal Gland Osmoregulatory Role In The Crayfish, Orconectes Putnami, Michael E. Fultz

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michael E. Fultz on August 1, 1997.

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Marine Farm Planning And Consultation Processes In Western Australia, Dave Everall Aug 1997

Marine Farm Planning And Consultation Processes In Western Australia, Dave Everall

Fisheries Management Papers

The development of a sustainable aquaculture industry in Western Australia is considered to be a high priority by the Government. The marine farming industry has a bright future in Western Australia, but there is a need to balance its developing needs for suitable waters with those of existing activities, and with community expectations for accountability and transparency in the resolution of equity and resource sharing decisions. The purpose of this report is to review the existing planning and consultation processes for pearling and aquaculture in WA and recommend how they may be improved and incorporated into a single process. It …

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Characterization Of The Sediment Bacterial Community In Groundwater Discharge Zones Of An Alkaline Fen: A Seasonal Study, Timothy C. Gsell, William E. Holben, Roy M. Ventullo Aug 1997

Characterization Of The Sediment Bacterial Community In Groundwater Discharge Zones Of An Alkaline Fen: A Seasonal Study, Timothy C. Gsell, William E. Holben, Roy M. Ventullo

Biological Sciences Faculty Publications

The cell density, activity, and community structure of the bacterial community in wetland sediments were monitored over a 13-month period. The study was performed at Cedar Bog, an alkaline fen. The objective was to characterize the relationship between the sediment bacterial community in groundwater upwelling zones and the physical and chemical factors which might influence the community structure and activity. DNA, protein, and lipid synthesis were measured at three different upwelling zones by using [H-3]thymidine, [C-14]leucine, and [C-14]glucose incorporation, respectively. The physiological status (apparent stress) of the consortium was assessed by comparing [C-14]glucose incorporation into membrane and that into storage …

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A Profile Of Antibiotic Resistant Bacteria In The James River, Keith Allen Boisvert Aug 1997

A Profile Of Antibiotic Resistant Bacteria In The James River, Keith Allen Boisvert

Master's Theses

Spatial and temporal variability in the antibiotic resistance of bacterial assemblages in the lower portion of the James River was examined. The antibiotic resistance of culturable coliforms was compared to the resistance in the microbial community. Antibiotic resistance was determined via colony formation on media containing antibiotics. The antibiotics ampicillin, chloramphenicol, streptomycin and tetracycline were used at concentrations ranging from 10 to 500 ug/ml. Statistically significant differences in the mean number of antibiotic resistant isolates were observed among both sample sites and dates. The sampling site at river mile 99 just below Richmond showed both increased antibiotic resistance and bacterial …

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Evolutionary Constraints On Population Structure: The Parasites Of Fundulus Zebrinus (Pisces: Cyprinodontidae) In The South Platte River Of Nebraska, John J. Janovy Jr., Scott D. Snyder, Richard E. Clopton Aug 1997

Evolutionary Constraints On Population Structure: The Parasites Of Fundulus Zebrinus (Pisces: Cyprinodontidae) In The South Platte River Of Nebraska, John J. Janovy Jr., Scott D. Snyder, Richard E. Clopton

Biology Faculty Publications

Population and community descriptor values (parasites per host, prevalence per parasite species, variance/mean ratios, species density, and diversity indices) for the 7-species parasite community of 61 relatively homogeneous samples of Fundulus zebrinus (Pisces: Cyprinodontidae) in the South Platte River of Nebraska, U.S.A., taken over a 14-yr period, are reported. South Platte River streamflow fluctuates over two orders of magnitude on several time scales-monthly, annually, and over multiple year wet-dry cycles. Relatively homogeneous sampling of a single host species with several parasite species provided a system that allowed assessment of the contribution of evolved parasite life cycles to population structure in …

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Corticosterone Levels During Nest Departure Of Juvenile American Kestrels, Julie Heath Aug 1997

Corticosterone Levels During Nest Departure Of Juvenile American Kestrels, Julie Heath

Biology Faculty Publications and Presentations

Many avian behavior patterns, such as breeding, migration and territoriality, are correlated with changes in hormone levels. Elevated levels of corticosterone, an adrenal steroid hormone, are associated with increased foraging and increased activity levels in birds. Young birds about to take their first flight may benefit from elevated plasma corticosterone levels that facilitate locomotor activity and foraging behavior while they are developing flight and hunting skills. I examined the relationship between corticosterone levels and the timing of nest departure in nestling American Kestrels (Falco sparverius). American Kestrels are cavity nesters and typically depart from the nest between 25-30 …

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The Role Of Free Radicals In The Plant's Response To Pathogen Attack In Tobacco, Phillip L. Peters Aug 1997

The Role Of Free Radicals In The Plant's Response To Pathogen Attack In Tobacco, Phillip L. Peters

Masters Theses

Previous studies have implicated the involvement of free radicals, specifically reactive oxygen species (ROS), as a key component in plant response to pathogen attack. In this study we examined the effect free radical scavenging compounds have on lesion area, salicylic acid levels, catalase, and superoxide dismutase in response to inoculation with Tobacco Mosaic Virus (TMV), a viral pathogen. Hydroponically grown Nicotiana tabacum (Xanthi nc) were pretreated with one of two antioxidants, either purpurogallin (PPG) or N-acetyl cysteine (NAC). Antioxidants were supplied to the plant via the root system and the leaves were subsequently challenged by inoculation with theTMV. Leaf material …

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Oxyconformity In Burrow-Dwelling Crustaceans : Aerobic Metabolism Of Hemisquilla Ensigera Californiensis, Leandra P. Peters Aug 1997

Oxyconformity In Burrow-Dwelling Crustaceans : Aerobic Metabolism Of Hemisquilla Ensigera Californiensis, Leandra P. Peters

Loma Linda University Electronic Theses, Dissertations & Projects

Hemisquilla ensigera califomiensis is an active burrow-dwelling stomatopod crustacean common off the coast of Southern California (Basch and Engle, 1989). In this experiment I measured the typical burrow oxygen level, time taken to deplete the oxygen in an inhabited, capped burrow, and tested the hypothesis that H. ensigera, like other burrow dwellers that have been examined, is an oxyregulator; and that like crustaceans in general, they have only limited anaerobic capabilities. Contrary to expectations, I found that H. ensigera is an oxyconformer or at best a weak oxyregulator, and that the species has substantial anaerobic capacity. Since it was …

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Multiple Isoforms Of Gaga Factor, A Critical Component Of Chromatin Structure, C Benyajati, L Mueller, N Xu, M Pappano, J Gao, M Mosammaparast, D Conklin, H Granok, C Craig, Sarah C.R. Elgin Aug 1997

Multiple Isoforms Of Gaga Factor, A Critical Component Of Chromatin Structure, C Benyajati, L Mueller, N Xu, M Pappano, J Gao, M Mosammaparast, D Conklin, H Granok, C Craig, Sarah C.R. Elgin

Biology Faculty Research

The GAGA transcription factor of Drosophila melanogaster is ubiquitous and plays multiple roles. Characterization of cDNA clones and detection by domain- specific antibodies has revealed that the 70-90 kDa major GAGA species are encoded by two open reading frames producing GAGA factor proteins of 519 amino acids (GAGA-519) and 581 amino acids (GAGA-581), which share a common N-terminal region that is linked to two different glutamine-rich C-termini. Purified recombinant GAGA-519 and GAGA-581 proteins can form homomeric complexes that bind specifically to a single GAGA sequence in vitro. The two GAGA isoforms also function similarly in transient transactivation assays in tissue …

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Isolation, Characterization, And Diversity Of Microorganisms From Amber, Raúl J. Cano Jul 1997

Isolation, Characterization, And Diversity Of Microorganisms From Amber, Raúl J. Cano

Biological Sciences

Retrieval of viable bacteria from fossil material dating from the Oligocene back to the Miocene opens the opportunity to study the evolution of prokaryotes through the evolution of their DNA, their physiology, and their ecology. This unique system in which ancient organisms and their genes may be compared directly, rather than by inference, with modern homologues is without precedent. Clearly, however, confirmation of the fossil origin of such isolates must be made in a manner that would allay reasonable skepticism. Present approaches of verification of authenticity of fossil DNA are either arbitrary or potentially unconvincing, because of their dependence on …

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The Effect Of Lymph Sac Pressure On Lymph Heart Pressure Development In The Toad Bufo Marinus, Michael Georgitsis Jul 1997

The Effect Of Lymph Sac Pressure On Lymph Heart Pressure Development In The Toad Bufo Marinus, Michael Georgitsis

Dissertations and Theses

Lymph hearts play an important role in blood volume regulation in anurans by controlling the movement of fluid from the lymphatic spaces to the vasculature. The anatomical continuity between lymph sacs and lymph hearts predicts a coupling of pressure between the two structures which may represent a physical basis for lymph heart regulation. The precise relationship between lymph heart pressure and lymph heart output was not examined so that conclusions regarding changes in work performed by the hearts as a result of changing lymph sac pressure could not be made. However, increases in lymph sac pressure led to increases in …

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Ms2 Coat Protein Mutants Which Bind Qβ Rna, Marc Spingola, David Peabody Jul 1997

Ms2 Coat Protein Mutants Which Bind Qβ Rna, Marc Spingola, David Peabody

Biology Department Faculty Works

The coat proteins of the RNA phages MS2 and Qβ are structurally homologous, yet they specifically bind different RNA structures. In an effort to identify the basis of RNA binding specificity we sought to isolate mutants that convert MS2 coat protein to the RNA binding specificity of Qβ. A library of mutations was created which selectively substitutes amino acids within the RNA binding site. Genetic selection for the ability to repress translation from the Qβ translational operator led to the isolation of several MS2 mutants that acquired binding activity for Qβ RNA. Some of these also had reduced abilities to …

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A Pouplation Genetic Study Of Wild Bottlenose Dolphins (Tursiops Truncatus) In Matagorda Bay, Texas, Joel Stephen Lenox Jul 1997

A Pouplation Genetic Study Of Wild Bottlenose Dolphins (Tursiops Truncatus) In Matagorda Bay, Texas, Joel Stephen Lenox

Dissertations and Theses

A long-term photoidentification study was initiated in response to an unusually high incidence of bottlenose dolphin mortality between Corpus Christi and Matagorda Bays, Texas. Blood samples from 36 captured and released animals were analyzed using three genetic techniques; mtDNA haplotyping, nuclear DNA fingerprinting and electrophoretic analysis of hemoglobin. Two Hinf I mtDNA haplotypes previously described in bottlenose dolphins from other locations within the Gulf of Mexico were discovered. Similarity Indices (SI) were calculated based on nuclear DNA fingerprinting data. These SI values were used as a relative measure of relatedness between two individuals run on the same gel. Means of …

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Ovarian Steroid Regulation Of Tryptophan Hydroxylase Enzyme Level In The Midbrain Raphe In Ovariectomized Guinea Pigs, Zhidong Lu Jul 1997

Ovarian Steroid Regulation Of Tryptophan Hydroxylase Enzyme Level In The Midbrain Raphe In Ovariectomized Guinea Pigs, Zhidong Lu

Dissertations and Theses

Progesterone stimulates prolactin secretion in estrogen ( estradiol-17-~)primed monkeys and guinea pigs. It is hypothesized that the serotonin neural system plays a pivotol role in mediating the effect of progesterone on prolactin secretion. Indeed, progesterone, but not estrogen, increases serotonin levels in the midbrain raphe in guinea pigs. However, estrogen alone stimulates gene expression of the rate-limiting enzyme for serotonin synthesis, tryptophan hydroxylase (TPH), and progesterone supplement to the estrogen regimen has no additive effect, as indicated by TPH mRNA levels in monkeys. The discrepancy between ovarian steroid effects on the TPH mRNA level and the serotonin level might be …

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The Role Of The Hepatic Vagus In The Pathogenesis Of Fever, Christopher Todd Simons Jul 1997

The Role Of The Hepatic Vagus In The Pathogenesis Of Fever, Christopher Todd Simons

Dissertations and Theses

Recent evidence has suggested a role of vagal afferents in the pathogenesis of fever. Although bilateral truncal subdiaphragmatic vagotomy has been shown to attenuate the febrile response to lipopolysaccharide (LPS) and interleukin-1, no study has yet been able to verify which of the five subdiaphragmatic vagal branches (viz., the anterior and posterior celiac branches, the anterior and posterior gastric branches, and the hepatic branch) is responsible for communicating this signal. The present study tested the hypothesis that the hepatic vagal branch mediates pyrogenic signals from the periphery to the brain. Male Wistar rats underwent one of four selective …

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Detection Of Dna Damage By Use Of Escherichia Coli Carrying Reca'::Lux, Uvra'::Lux, And Alka'::Lux Reporter Plasmids, Amy Cheng Vollmer, S. Belkin, D. R. Smulski, T. K. Van Dyk, R. A. Larossa Jul 1997

Detection Of Dna Damage By Use Of Escherichia Coli Carrying Reca'::Lux, Uvra'::Lux, And Alka'::Lux Reporter Plasmids, Amy Cheng Vollmer, S. Belkin, D. R. Smulski, T. K. Van Dyk, R. A. Larossa

Biology Faculty Works

Plasmids were constructed in which DNA damage-inducible promoters recA, uvrA, and alkA from Escherichia coli were fused to the Vibrio fischeri luxCDABE operon. Introduction of these plasmids into E. coli allowed the detection of a dose-dependent response to DNA-damaging agents, such as mitomycin and UV irradiation. Bioluminescence was measured in real time over extended periods. The fusion of the recA promoter to luxCDABE showed the most dramatic and sensitive responses. lexA dependence of the bioluminescent SOS response was demonstrated, confirming that this biosensor's reports were transmitted by the expected regulatory circuitry. Comparisons were made between luxCDABE and lacZ fusions to …

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