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Determination Of Nuclear Factor-Kappa B Activation In Cultured Renal Epithelial Cells And Cardiac Myocytes Exposed To Cocaine And Morphine, David Angeles Tiangco

Biological Sciences Theses & Dissertations

Nuclear factor-kappa B (NF-kB) is an important transcription factor that participates in the genetic regulation of inflammation in many tissues. Cocaine and heroin are drugs of abuse associated with renal and cardiac pathology. The purpose of this study was to test the hypothesis that exposure to cocaine or morphine (a metabolite of heroin) would activate NF-kB in renal epithelial cells (COS-7) and cardiac myocytes (H9c2) grown in culture. COS-7 and H9c2 cells were co-transfected with an experimental reporter specific for NF-kB activation and a control reporter with constitutive activity. A dual-luciferase assay was used to determine levels of NF-kB activation …

The Role Of Glutathione In The Defense Pathway Response Of Arabidopsis Thaliana To The Pathogen Pseudomonas Syringae Pathovar Tomato Dc3000 Avrb, Allison Patrice Mckenna

Masters Theses

Inoculation of Arabidopsis thaliana with Pseudomonas syringae pv. tomato DC3000 AvrB (Pst) results in a series of biochemical changes, including an oxidative burst, accumulation of salicylic acid, (de)phosphorylation of proteins, localization of transcription factors to the nucleus and ultimately expression of pathogenesis-related genes. The redox status within plant cells, which is maintained by a cycle of antioxidants that are largely dependent on the reduced form of glutathione (GSH), because of its ability to donate electrons that are necessary to quench reactive oxygen species (ROS). This study focuses on the role of glutathione in the early defense responses of Arabidopsis to …

The Physiological And Biochemical Characteristics Of Saccharomycetalean Yeasts Associated Endosymbiotically With Beetles In The Macroscopic Fruiting Bodies Of Basidiomycetes, Ebony Antoinette Spikes

Honors Capstones

No abstract provided.

Enrichments And Isolations Of Mesophilic And Thermophilic Iron-Reducing Microbes From Deep-Sea Hydrothermal Vents And The Deep Subsurface, Melissa Mary Kendall

Dissertations and Theses

Microbes inhabiting the deep subsurface play an important role in geochemical processes and may be of practical value in bioremediation and biotechnology. Hydrothermal vents and the deep gold mines of South Africa have be likened to "windows" into the subsurface biosphere. The aim of this research was to isolate and characterize microbes involved in iron-cycling from deep-sea hydrothermal vents and from the deep gold mines of the Witwatersrand Basin. Three mesophilic bacteria, strains BB4, W3, and A6 were isolated from sulfide chimneys at 13°N and a thermophilic bacterium, strain GB21 was isolated from Guaymas Basin on the East Pacific Rise. …

Interspecific- And Acclimation-Induced Variation In Levels Of Heat-Shock Proteins 70 (Hsp70) And 90 (Hsp90) And Heat-Shock Transcription Factor-1 (Hsf1) In Congeneric Marine Snails (Genus Tegula): Implications For Regulation Of Hsp Gene Expression, Lars Tomanek, George N. Somero

Biological Sciences

In our previous studies of heat-shock protein (hsp) expression in congeneric marine gastropods of the genus Tegula, we observed interspecific and acclimation-induced variation in the temperatures at which heat-shock gene expression is induced (T_on). To investigate the factors responsible for these inter- and intraspecific differences in T_on, we tested the predictions of the ‘cellular thermometer’ model for the transcriptional regulation of hsp expression. According to this model, hsps not active in chaperoning unfolded proteins bind to a transcription factor, heat-shock factor-1 (HSF1), thereby reducing the levels of free HSF1 that are available to bind …

The Nmda Receptor M3 Segment Is A Conserved Transduction Element Coupling Ligand Binding To Channel Opening, Kevin Jones, Hendrika Vandongen, Antonius Vandongen

Department of Biology Faculty Publications

Ion channels alternate stochastically between two functional states, open and closed. This gating behavior is controlled by membrane potential or by the binding of neurotransmitters in voltage- and ligand-gated channels, respectively. Although much progress has been made in defining the structure and function of the ligand-binding cores and the voltage sensors, how these domains couple to channel opening remains poorly understood. Here we show that the M3 transmembrane segments of the NMDA receptor allosterically interact with both the ligand-binding cores and the channel gate. It is proposed that M3 functions as a transduction element whose conformational change couples ligand binding …

Serotonin Modulates Oscillations Of The Membrane Potential In Isolated Spinal Neurons From Lampreys, I. V. Batueva, James T. Buchanan, N. P. Veselkin, E. I. Suderevskaya, E. A. Tsvetkov

Biological Sciences Faculty Research and Publications

Studies were performed on spinal neurons from lampreys isolated by an enzymatic/mechanical method using pronase. The effects of 100 µM serotonin (5-HT) on membrane potential oscillations induced by a variety of excitatory amino acids were studied. 5-HT was found to depolarize branched cells (presumptive motoneurons and interneurons) by 2–6 mV without inducing membrane potential oscillations. However, when oscillations were already present because of an excitatory amino acid, 5-HT changed the parameters of these oscillations, increasing the amplitudes of all types of oscillations, increasing the frequency of irregular oscillations, and increasing the duration of the depolarization plateaus accompanied by action potentials. …

Smooth Muscle Myosin Heavy Chain Isoform Distribution In The Swine Stomach, Jonathan A. Parisi, Thomas J. Eddinger

Biological Sciences Faculty Research and Publications

To evaluate the distribution of smooth muscle myosin heavy chain isoforms (SMB, with head insert), we examined frozen sections from the various regions of swine stomachs using isoform-specific antibodies. We previously reported variable SMB myosin heavy chain (MHC) expression in stomach cells that correlates with unloaded shortening velocities. This is consistent with the generalization of tonic fundic muscle having low expression and phasic antral muscle having high expression of the SMB MHC isoform. Using immunohistochemistry (IHC), we show a progression of the SMB MHC from very low immunoreactivity in the fundus to very intense immunoreactivity in the antrum. In the …

Effects Of Herbivory On The Reproductive Effort Of 4 Prairie Perennials, Erica Spotswood, Kate L. Bradley, Johannes M. H. Knops

School of Biological Sciences: Faculty Publications

Background: Herbivory can affect every aspect of a plant's life. Damaged individuals may show decreased survivorship and reproductive output. Additionally, specific plant species (legumes) and tissues (flowers) are often selectively targeted by herbivores, like deer. These types of herbivory influence a plant's growth and abundance. The objective of this study was to identify the effects of leaf and meristem removal (simulated herbivory within an exclosure) on fruit and flower production in four species (Rhus glabra, Rosa arkansana, Lathyrus venosus, and Phlox pilosa) which are known targets of deer herbivory.

Results: Lathyrus never flowered or went to …

Occam's Razor & The Nature Of Scientific Theories, William D. Stansfield

Biological Sciences

No abstract provided.

An Ecological And Evolutionary Analysis Of Photosynthetic Thermotolerance Using The Temperature-Dependent Increase In Fluorescence, Charles A. Knight, David D. Ackerly

Biological Sciences

The hypothesis that species inhabiting warmer regions have greater photosynthetic tolerance of high temperatures was tested using the temperature-dependent increase in fluorescence (T-F_o). Congeneric species pairs of Atriplex, Salvia, Encelia, and Eriogonum with desert versus coastal distributions were studied in a common environment and in the field. In addition, 21 species with contrasting microclimate distributions were studied at a field site in a northern California chaparral community. The average July maximum temperature within the current distributions of species was quantified using a geographic information system. Four parameters (T_crit, T_S20, …

Leaf Size, Specific Leaf Area And Microhabitat Distribution Of Chaparral Woody Plants: Contrasting Patterns In Species Level And Community Level Analyses, D. D. Ackerly, Charles A. Knight, S. B. Weiss, K. Barton, K. P. Starmer

Biological Sciences

We examined variation in leaf size and specific leaf area (SLA) in relation to the distribution of 22 chaparral shrub species on small-scale gradients of aspect and elevation. Potential incident solar radiation (insolation) was estimated from a geographic information system to quantify microclimate affinities of these species across north- and south-facing slopes. At the community level, leaf size and SLA both declined with increasing insolation, based on average trait values for the species found in plots along the gradient. However, leaf size and SLA were not significantly correlated across species, suggesting that these two traits are decoupled and associated with …

Biological Implications Of The Weibull And Gompertz Models Of Aging, Robert Ricklefs, Alex Scheuerlein

Biology Department Faculty Works

Gompertz and Weibull functions imply contrasting biological causes of demographic aging. The terms describing increasing mortality with age are multiplicative and additive, respectively, which could result from an increase in the vulnerability of individuals to extrinsic causes in the Gompertz model and the predominance of intrinsic causes at older ages in the Weibull model. Experiments that manipulate extrinsic mortality can distinguish these biological models. To facilitate analyses of experimental data, we defined a single index for the rate of aging (ω) for the Weibull and Gompertz functions. Each function described the increase in aging-related mortality in simulated ages at death …

A Motor And A Brake: Two Leg Extensor Muscles Acting At The Same Joint Manage Energy Differently In A Running Insect, Anna N. Ahn, Robert J. Full

All HMC Faculty Publications and Research

The individual muscles of a multiple muscle group at a given joint are often assumed to function synergistically to share the load during locomotion. We examined two leg extensors of a running cockroach to test the hypothesis that leg muscles within an anatomical muscle group necessarily manage (i.e. produce, store, transmit or absorb) energy similarly during running. Using electromyographic and video motion-analysis techniques, we determined that muscles 177c and 179 are both active during the first half of the stance period during muscle shortening. Using the in vivo strain and stimulation patterns determined during running, we measured muscle power output. …

Cost Of Defense In The Context Of Plant Competition: Brassica Rapa May Grow And Defend, David H. Siemens, Shannon H. Garner, Thomas Mitchell-Olds, Ragan M. Callaway

Biological Sciences Faculty Publications

Theory on costs of plant defense against herbivory in stressful environments predicts that costs should increase when competition is intense. This amplifies a fundamental dilemma that plants are thought to face: allocate limited resources to grow fast enough to compete, or invest these resources in secondary metabolites to maintain defense. We studied costs associated with genetic and environmental variation in secondary metabolite production of Brassica rapa in the presence and absence of the generalist competitor Lolium perenne. We used experimental quantitative genetics (artificial selection) to manipulate genetic variation, and herbivore-induction treatments to produce environmental variation in myrosinase and glucosinolate …

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

Thin Filament Diversity And Physiological Properties Of Fast And Slow Fiber Types In Astronaut Leg Muscles, Danny A. Riley, James L. W. Bain, Joyce L. Thompson, Robert H. Fitts, Jeffrey J. Widrick, Scott W. Trappe, Todd A. Trappe, David L. Costill

Biological Sciences Faculty Research and Publications

Slow type I fibers in soleus and fast white (IIa/IIx, IIx), fast red (IIa), and slow red (I) fibers in gastrocnemius were examined electron microscopically and physiologically from pre- and postflight biopsies of four astronauts from the 17-day, Life and Microgravity Sciences Spacelab Shuttle Transport System-78 mission. At 2.5-µm sarcomere length, thick filament density is ~1,012 filaments/µm² in all fiber types and unchanged by spaceflight. In preflight aldehyde-fixed biopsies, gastrocnemius fibers possess higher percentages (~23%) of short thin filaments than soleus (9%). In type I fibers, spaceflight increases short, thin filament content from 9 to 24% in soleus and …

Neurospora Clock-Controlled Gene 9 (Ccg-9) Encodes Trehalose Synthase: Circadian Regulation Of Stress Responses And Development, Mari L. Shinohara, Alejandro Correa, Deborah Bell-Pedersen, Jay C. Dunlap, Jennifer J. Loros

Dartmouth Scholarship

The circadian clock of Neurospora crassa regulates the rhythmic expression of a number of genes encoding diverse functions which, as an ensemble, are adaptive to life in a rhythmic environment of alternating levels of light and dark, warmth and coolness, and dryness and humidity. Previous differential screens have identified a number of such genes based solely on their cycling expression, including clock-controlled gene 9 (ccg-9). Sequence analysis now shows the predicted CCG-9 polypeptide to be homologous to a novel form of trehalose synthase; as such it would catalyze the synthesis of the disaccharide trehalose, which plays an important …

Iron, Folate And Vitamin B12 Status Of Apparently Healthy Irish Adult Women Attending General Practitioners In Inner-City Dublin, Helen R. Casey

Doctoral

There is substantial related morbidity and mortality among men and women in developed countries. Certain events during the course of a woman’s life such as menstruation, pregnancy, lactation and the menopause may compromise haematinic nutrient status. The purpose of this study was to investigate iron, folate and vitamin B12 status among a sample of apparently healthy, non-pregnant Irish adult women attending general practitioners in inner-city Dublin. Dietary, socio-economic, medical and lifestyle factors contributing to status of these haematinic nutrients were extensively examined. The initial part of the work validated the methods in a representative sample of inner city Dublin women …

Thin Laser Light Sheet Microscope For Microbial Oceanography, Eran Fuchs, Jules S. Jaffe, Richard A. Long, Farooq Azam

Faculty Publications

Despite a growing need, oceanographers are limited by existing technological constrains and are unable to observe aquatic microbes in their natural setting. In order to provide a simple and easy to implement solution for such studies, a new Thin Light Sheet Microscope (TLSM) has been developed. The TLSM utilizes a well-defined sheet of laser light, which has a narrow (23 micron) axial dimension over a 1 mm x 1 mm field of view. This light sheet is positioned precisely within the depth of field of the microscope’s objective lens. The technique thus utilizes conventional microscope optics but replaces the illumination …

Shortening Velocity And Myosin Heavy- And Light-Chain Isoform Mrna In Rabbit Arterial Smooth Muscle Cells, Jennifer J. Sherwood, Thomas J. Eddinger

Biological Sciences Faculty Research and Publications

In smooth muscle cells (SMCs) isolated from rabbit carotid, femoral, and saphenous arteries, relative myosin isoform mRNA levels were measured in RT-PCR to test for correlations between myosin isoform expression and unloaded shortening velocity. Unloaded shortening velocity and percent smooth muscle myosin heavy chain 2 (SM2) and myosin light chain 17b (MLC_17b) mRNA levels were not significantly different in single SMCs isolated from the luminal and adluminal regions of the carotid media. Saphenous artery SMCs shortened significantly faster (P < 0.05) than femoral SMCs and had more SM2 mRNA (P < 0.05) than carotid SMCs and less MLC_17b mRNA (P < 0.001) and higher tissue levels of SMB mRNA (P < 0.05) than carotid and femoral SMCs. No correlations were found between percent SM2 and percent MLC_17b mRNA levels and unloaded shortening velocity in SMCs from these arteries. …

Quantum Computing: From Bragg Reflections To Decoherence Estimates, Peter Pfeifer, Chen Hou

Biological Sciences Faculty Research & Creative Works

We give an exposition of the principles of quantum computing (logic gates, exponential parallelism from polynomial hardware, fast quantum algorithms, quantum error correction, hardware requirements, and experimental milestones). A compact description of the quantum Fourier transform to find the period of a function-the key step in Shor's factoring algorithm-illustrates how parallel state evolution along many classical computational paths produces fast algorithms by constructive interference similar to Bragg reflections in x-ray crystallography. On the hardware side, we present a new method to estimate critical time scales for the operation of a quantum computer. We derive a universal upper bound on the …

Performance Limits Of Labriform Propulsion And Correlates With Fin Shape And Motion, Jeffrey A. Walker, Mark W. Westneat

Biology

Labriform locomotion, which is powered by oscillating the paired pectoral fins, varies along a continuum from rowing the fins back and forth to flapping the fins up and down. It has generally been assumed (i) that flapping is more mechanically efficient than rowing, a hypothesis confirmed by a recent simulation experiment, and (ii) that flapping should be associated with wing-shaped fins while rowing should be associated with paddle-shaped fins, To determine whether these hypotheses and the results of the simulation experiment are consistent with natural variation, we compared the steady swimming performance (critical swimming speed) of four species of labrid …

Electrophoretic Aspects Of Blood Serum Proteins Of The Genus Apodemus In The Black Sea Region, Reyhan Çolak

Turkish Journal of Biology

Globulin and albumin proteins of Apodemus populations in the Black Sea region were examined using SDS-PAGE (sodium dodecyl sulphate - polyacrylamide gel electrophoresis). There were 7-11 bands in the globulin region and 1-3 bands in the prealbumin zone. It was determined that there were variations in both the globulin region and the prealbumin zone in populations of this genus. A band was observed in the postalbumin zone with different electrophoretic mobilities including slow and fast. This different mobility in the postalbumin zone separated Apodemus specimens into two different populations in sympatry. These findings showed that at least two populations of …

Partial Purification Of Intestinal Triglyceride Lipase From Cyprinion Macrostomus Heckel, 1843 And Effect Of Ph On Enzyme Activity, Naci̇ Değerli̇, M. Ali̇ Akpinar

Turkish Journal of Biology

Intestinal triglyceride lipase (TG) of Cyprinion macrostomus after precipitation with 30% polyethylene glycol (PEG), was partially purified by hydrophobic interaction chromatography on phenyl sepharose CL-4B, and the effect of pH on this enzyme activity was determined titrimetrically. Intestinal tissue homogenates were precipitated using 30% PEG-8000, and then applied onto a phenyl sepharose CL-4B column for hy-drophobic interaction chromatography. The lipase that bound to this hydrophobic resin and was partially purified by this single step application was then eluted from this resin with taurocholic acid and Triton X-100 elution. This purified enzyme effectively hydrolysed natural olive oil substrate under the experimental …

Hydroxyurea Induces P53 Accumulation And Apoptosis In Human Cervical Carcinoma Cells, Hakan Akça, Osman Ni̇dai̇ Özeş

Turkish Journal of Biology

Cervical carcinoma is one type of cancer with a high mortality rate in women. In this research, we investigated the cytotoxic, antiproliferative and apoptosis-inducing effects of hydroxyurea on a human cervical carcinoma cell line, HeLa. We found that hydroxyurea has cytotoxic and antiproliferative effects on HeLa cells in a dose-dependent manner. We also found that hydroxyurea can increase cellular levels of p53 and p21, and induce DNA fragmentation in a dose-dependent manner. We concluded that the observed antiproliferative, cytotoxic and apoptosis inducing activities of hydroxyurea might be mediated by the induction of p53 and its transcriptional target, p21.

Analysis Of The Effects Of Hyperosmotic Stress On The Derepression Of Invertase Activities And The Growth Of Different Baker's Yeast Strains, Sezai̇ Türkel, Tülay Turgut

Turkish Journal of Biology

The growth of baker's yeast Saccharomyces cerevisiae in medium containing sucrose requires a high level of extracellular invertase enzyme activity. However, the expression of invertase is under the strict control of glucose repression in S. cerevisiae. In addition, invertase enzyme activity is also affected by physiological stress conditions that baker's yeast is exposed to during the various stages of industrial level production and downstream processing. We analyzed the effect of hyperosmotic stress on the derepression of invertase activities of a haploid laboratory yeast strain and three different industrial baker's yeast strains. Our results indicated that hyperosmotic stress interferes with the …

Effect Of Experimental Diabetes Mellitus On Plasma Lactate Dehydrogenase And Glutamic Oxaloacetic Transaminase Levels In Rabbits, İsmai̇l Çeli̇k, Eşref Yeği̇n, Fehmi̇ Odabaşoğlu

Turkish Journal of Biology

Hyperglycemia was induced in 20 male, white, New Zealand rabbits (2-3 kg) (Oryctolagus cuniculus huxley) by alloxan (100 mg/kg body weight, I.V.) and maintained for 16 weeks without insulin treatment. Blood samples were taken from both diabetic and non-diabetic rabbits at the same time for measurement of plasma enzymes. Levels of glutamic oxalacetic transaminase (GOT) and lactate dehydrogenase (LDH) were determined after treatment. The levels of LDH and GOT were 155.6 ± 41.9 U/L and 47.0 ± 20.4 U/L in the control group respectively. These parameters were 286.9 ± 142.9 U/L and 93.9 ± 62.5 U/L in the diabetic group …

Protoplast Fusion In Sugar Beet (Beta Vulgaris L.), Songül Gürel, Ekrem Gürel, Zeki̇ Kaya

Turkish Journal of Biology

In this study, attempts were made to fuse the suspension-derived protoplasts of a sugar beet breeding line (ÇBM315) with the mesophyll-derived protoplasts of three breeding lines (M114, ELK345 and M1017), which were obtained from our previous experiments. Combinations of three different PEG concentrations (20%, 25% or 30%) and three different treatment durations (15, 20 or 25 min) were tested. The fusion efficiency was determined by measuring the viability, heterokaryon frequency and plating efficiency (PE) of the fused protoplasts after four weeks of culture. In general, 25% PEG combined with 20 min treatment duration produced the highest fusion frequency, but the …

Accumulation Of Poly-\Beta-Hydroxybutyrate In Streptomyces Species During Growth With Different Nitrogen Sources, Aysel Uğur, Nuretti̇n Şahi̇n, Yavuz Beyatli

Turkish Journal of Biology

The accumulation of poly-\beta-hydroxybutyric acid (PHB) in 27 Streptomyces isolates with different taxonomical properties was investigated. The amount of synthesized PHB was determined as crotonic acid by spectrophotometry. Eighty percent of the tested isolates accumulated PHB between 0.3 and 7.6% of dry mycelial weight. PHB was produced by a selectant of Streptomyces isolates in media containing different nitrogen sources (KNO_3, glycine, peptone, proteose peptone, L-asparagine, tryptone and malt extract), each combined with 2 g/l glucose as the carbon source. The most effective PHB production was observed on glycine/glucose medium with a 7.6% dry mycelial weight. Nitrogen limiting conditions were inhibitory …