Biology Commons^™

Daughter Cells Of Saccharomyces Cerevisiae From Old Mothers Display A Reduced Life Span, Nicanor Austriaco, Brian K. Kennedy, Leonard Guarente

Biology Faculty Publications

The yeast Saccharomyces cerevisiae typically divides asymmetrically to give a large mother cell and a smaller daughter cell. As mother cells become old, they enlarge and produce daughter cells that are larger than daughters derived from young mother cells. We found that occasional daughter cells were indistinguishable in size from their mothers, giving rise to a symmetric division. The frequency of symmetric divisions became greater as mother cells aged and reached a maximum occurrence of 30% in mothers undergoing their last cell division. Symmetric divisions occurred similarly in rad9 and ste12 mutants. Strikingly, daughters from old mothers, whether they arose …

Scanning Electron Microscopic Study Of The Collagen Sheath Of The Human Thyroid Gland And Its Disorders, Masao Morita, Takuro Ogata, Keijiro Araki

Scanning Microscopy

A cell-maceration/scanning electron microscope (SEM) method was employed to demonstrate the collagen sheath around follicles (perifollicular sheath) of the human thyroid gland and its disorders. In the normal thyroid gland, the follicles were surrounded by spherical collagen sheaths composed of a framework of thick collagen bands 1-5 μm in width and fine solitary collagen fibrils 50-70 nm in diameter. In benign thyroid diseases (Graves' disease, Hashimoto's thyroiditis and adenomatous goiter), the perifollicular sheaths differed in size and in shape according to the disease, but they were always composed of thick collagen bands and fine fibrils as in the normal thyroid. …

A Survey Of Source And Finished Water Supplies For Giardia Cysts And Cryptosporidium, Lisa Martin Sexton

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 Lisa Martin Sexton on December 1, 1994.

Isolation Of Three Hexahydro-1,3,5-Trinitro-1,3,5-Triazine- Degrading Species Of The Family Enterobacteriaceae From Nitramine Explosive-Contaminated Soil, Christopher Kitts, Daryl P. Cunningham, Pat J. Unkefer

Biological Sciences

Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third isolate, identified as Citrobacter freundii, partially transformed RDX and generated high concentrations of nitroso-RDX intermediates. All three isolates produced ¹⁴CO₂ from labeled RDX under O₂-depleted culture conditions. While all three isolates transformed HMX, only M. morganii transformed HMX in the presence of RDX.

Second Intermediate Host-Specificity Of Haematoloechus Complexus And Haematoloechus Medioplexus (Digenea: Haematoloechidae), Scott D. Snyder, John J. Janovy

Biology Faculty Publications

Second intermediate host-specificity was examined for two species of the frog lung fluke genus Haematoloechus. Nine species of freshwater arthropods were exposed to cercariae of H. complexus and H. medioplexus. Metacercariae of H. complexus developed in all arthropod species used. Metacercariae of H. medioplexus developed only in anisopteran odonate naiads. This difference in host utilization may have epizootiological implications. The potential development of H. complexus in a greater number of arthropods than H. medioplexus may increase the chances of ingestion of H. complexus by an anuran host. The range of arthropods parasitized by H. complexus indicates that host-specificity …

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.

The Religious Dimensions Of The Biological Narrative, Ursula W. Goodenough

Biology Faculty Research

A cell/molecular biologist challenges the thesis that science and religion are two ways of experiencing and interpreting the world and explores instead the possible ways that the modern biological worldview might serve as a resource for religious perspectives. Three concepts—meaning, valuation, and purpose—are argued to be central to the entire biological enterprise, and the continuation of this enterprise is regarded as a sacred religious trust.

This article was originally delivered at the Templeton Symposium,„Science and Religion: Two Ways of Experiencing and Interpreting the World”organized by Zygon: Journal of Religion and Science and the Chicago Center for Religion and Science, 31 …

Estrogen Induced Eosinophil Migration Into The August Rat Uterus Is Associated With Intercellular Adhesion Molecule Expression, Daniel R. Orcutt

Masters Theses

Estrogen causes an influx of eosinophils into the uterus in female rats. The diapedesis of eosinophils out of the vasculature has also been observed in allergic reactions, parasitic infections, and atopic dermatitis, and has been associated with cellular adhesion molecules (CAMs). Antibody blocking studies against ICAM-1/ LFA-1 and VCAM-1/VLA-4 have suggested that both ligand/receptor sets of CAMs are involved in the selective recruitment of eosinophils out of the vasculature. ICAM- 1 is expressed on the vascular endothelium and decreases in expression when IL-4 is introduced. VLA-4 is present on eosinophils and is suspected to allow selective migration of eosinophils out …

Effect Of Lead On Flexor Muscle Contraction And Photochemically-Induced Platelet Aggregation In Pial Microcirculation Of The Mouse, Amna Hamad Al Dhaheri

Theses

Lead is one of many heavy metal ions that can effectively compete for the binding sites of calcium, block the calcium channels and disturb the ion exchange. As a result, lead would be expected to affect the calcium-mediated cell functions. Muscle contraction and platelet aggregation are two important functions in which Ca²⁺ plays a major role and ultimately are affected by lead. Experiments were carried out to investigate the effect of lead on mouse flexor muscle contraction and on photochemically-induced platelet aggregation in pial microcirculation. A study of an acute exposure (1, 5, 10 and 25 µM) and a …

Formation And Structure Of Dentine In The Rat Incisor After Chronic Exposure To Sodium Fluoride, J. Appleton

Scanning Microscopy

Weanling rats were chronically exposed to sodium fluoride by feeding them for eight weeks with a standard powdered diet incorporating sodium fluoride at 0.025% , 0.05% and 0.1% by weight. After eight weeks blood was removed by cardiac puncture and the levels of plasma calcium and phosphate determined. The incisor teeth were removed and their structure examined in the scanning electron microscope (SEM) using backscattered electron imaging to determine the relative concentration and distribution of the mineral phase in the dentine. There was no significant alteration to the normal serum calcium and phosphate levels. Small scattered interglobular spaces were seen …

Cryo-Jet Preservation Of Calcium In The Rat Spinal Cord, William B. Greene, Lyle G. Walsh

Scanning Microscopy

In order to determine the distribution of diffusible ions, especially calcium, in rat spinal cord axons before and after trauma, sham, 6 hours post 6 gm/cm and 20 gm/cm trauma cords were cryo-jet frozen in situ and cryo-sections were subjected to electron probe X-ray microanalysis. The results confirm part of the Ca hypothesis, i.e., some spinal cord axons accumulate intracellular Ca after traumatic injury. In addition, 6 hours after trauma, Ca is only accumulated by axons that have also lost homeostasis. Thus, it is likely that observations of the continual rise of Ca in the traumatized spinal cord are due …

Investigations On Glycolipid Production By Pseudomonas Putida Grown On Toluene In Batch And Continuous Culture Conditions, Keith Foorest Dockery

Dissertations and Theses

Utilization of toluene by Pseudomonas putida as its sole carbon and energy source affects morphology, outer membrane protein composition, and glycolipid production. Two strains of P. putida were found to utilize toluene and to coexist in continuous and batch culture. The two strains were designated translucent and opaque, based upon their readily identifiable coloration when grown on Luria agar. The translucent strain was the dominant strain in continuous culture conditions. The outer membrane proteins of P. putida were separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis. When toluene is the carbon and energy source, the trend in protein composition was …

Denitrification, Nutrient Regeneration And Carbon Mineralization In Sediments Of Galveston Bay, Texas, Usa, Andrew R. Zimmerman, Ronald Benner

Faculty Publications

Rates of benthic denitrification, oxygen consumption and nutrient regeneration were measured during winter, spring and summer in Galveston Bay (Texas, USA) sediments. Denitrification ranged from 0 to 47 µmol N₂ m^-2 h^-1 with maximal rates generally occurring in the summer and the upper estuary. Oxygen consumption rates ranged from 38 µmol O₂ m^-2 h^-1 in the winter to 353 µmol O₂ m^-2 h^-1 in the summer and were correlated with denitrification rates. Variations in bay water temperature accounted for 52 % of the variability associated with denitrification rates whereas only 28% …

Morphologic Changes Of Apoptosis Induced In Human Chronic Myelogenous Leukemia "Blast" Cells By Sc41661a (Searle), A Selective Inhibitor Of 5-Lipoxygenase, K. M. Anderson, T. M. Seed, J. Peng, A. Jajeh, J. Meng, J. E. Harris

Scanning Microscopy

Several inhibitors of the arachidonic acid-metabolizing enzyme, 5-lipoxygenase reduce proliferation of hematopoietic and non-hematopoietic cells and cell lines and some cells undergo limited differentiation. Cells were cultured from patients with chronic myelogenous leukemia in "blast" crisis with the selective inhibitor of 5-lipoxygenase,SC41661A[3-{3,5-bis(1,1-dimethyl)-4-hydroxyphenyl}hiol]-N-methyl-N-[2-(2-phridinyl-propanamide)]. Cells cultured for 3 to 5 days with 40 μM SC41661A exhibited reduced cellular numbers along with ultrastructural changes and DNA laddering characteristic of apoptosis. Similar culture conditions reduced proliferation of U937 monoblastoid cells. In U937 cells, the ultrastructural features of apoptosis were not observed at 72 hours, when DNA laddering was present and cell numbers were reduced, …

Urinary Glycosaminoglycans Are Selectively Included Into Calcium Oxalate Crystals Precipitated From Whole Human Urine, Koji Suzuki, Keiko Mayne, Ian R. Doyle, Rosemary L. Ryall

Scanning Microscopy

Urinary glycosaminoglycans are selectively included into calcium oxalate (CaOx) crystals precipitated from whole human urine: The presence of glycosaminoglycans (GAGs) in the organic matrix of urinary stones, and their known effects on CaOx crystallization have prompted speculation regarding their role in CaOx urolithiasis. The aim of this study was to examine the involvement of GAGs in the early stages of CaOx crystallization in human urine. Urine samples were collected from healthy men and CaOx crystallization was induced by the addition of a sodium oxalate load. The crystals were harvested and demineralized, and the GAG content of the resulting extract analysed …

Changes In Proteins Associated With Nitrogen Fixation And Iron Nutrition In The Marine Cyanobacterium Trichodesmium, Karen Marie Elardo

Dissertations and Theses

This investigation tested the hypothesis that iron, as a micronutrient, will affect proteins in Trichodesmium and therefore affect nitrogen fixation. Changes in proteins that are a result of iron enrichment were compared to naturally occurring diel changes. Alterations in the iron protein of nitrogenase were compared to nitrogen fixation rates using the acetylene reduction technique. The observed changes in proteins were compared in Trichodesmium colonies from the Caribbean Sea and the Sargasso Sea.

Trichodesmium colonies were monitored for protein and iron content over a diel period on two cruises. The changes in protein and iron content in Trichodesmium colonies were …

A Comparison Of Neutrophil Migration In The Mouse In Response To Infection With Three Species Of Trichinella, Jon Darin Prulhiere

Dissertations and Theses

The Genus Trichinella is currently thought to consist of 8 separate species. Several methods have been used to help differentiate these. In this study the ability of three of these species, T. spiralis, T. pseudospiralis, and T. sp. 3 to independently infect MRL++ mice was compared at 5, 7, 11, 18 and 20 days post infection (dpi) with the hope of discovering new distinguishing characteristics. Of interest was the development of inflammation through the accumulation of neutrophils associated with larvae of Trichinella in mouse skeletal muscle. This was evaluated with routine histological stains, endogenous peroxidase staining and immunohistochemical …

Bcl-2 And P53 Protein Expression In All Grades Of Astrocytomas, Robyn L. Castleberg

Capstone Research Projects

No abstract provided.

Functional Consequences Of Compartmentalization Of Synaptic Input, Melissa J. Coleman, Michael P. Nusbaum

WM Keck Science Faculty Papers

Intra-axonal recordings of stomatogastric nerve axon 1 (SNAX1) indicate that there are synaptic inputs onto the SNAX1 terminals in the stomatogastric ganglion (STG) of the crab Cancer borealis (Nusbaum et al., 1992b). To determine whether this synaptic input only influenced SNAX1 activity within the STG, we identified the SNAX1 soma in the commissural ganglion (CoG). We found that this neuron has a neuropilar arborization in the CoG and also receives synaptic inputs in this ganglion. Based on its soma location, we have renamed this neuron modulatory commissural neuron 1 (MCN1). While intracellular stimulation of MCN1soma and MCN1SNAX has the same …

Shark Bay World Heritage Area Draft Management Plan For Fish Resources, Fisheries Department Of Western Australia

Fisheries Management Papers

Shark Bay was inscribed on the World Heritage List in December 1991 on the basis of its natural values. The Department of Conservation and Land Management (CALM) is the management agency with responsibility for the oversight and development of management plans dealing with both the marine and terrestrial aspects of the World Heritage Area. This Draft plan deals with the management of fish resources in the Shark Bay World Heritage Area which are the responsibility of the Fisheries Department of Western Australia.

Cell Injury And Apoptosis, Andrejs Liepins, J. Omar Bustamante

Scanning Microscopy

Various forms of cellular injury, whether induced by immune effector cells, aberrant metabolic processes, chemotherapeutic drugs or temperature shifts, result in common morphological changes consisting of the formation and shedding of membrane vesicles from the injured cell surfaces, i.e., apoptosis. This dynamic cell surface membrane behavior appears to be dependent on the disruption of cytoplasmic microtubules. Concomitant with the altered cell surface morphology, certain physiological and biochemical events have been found to be associated with cell injury. These include changes in membrane permeability, elevated oxygen consumption rates and nuclear DNA fragmentation. However, it remains to be experimentally established which of …

Distribution Of Sodium, Magnesium, Chlorine, Calcium, Potassium, Phosphorus And Sulphur In Z-, I- And A-Bands In Mammalian Striated Muscle, Romuald Wróblewski, Lars Edström

Scanning Microscopy

The regularity of the striation of skeletal muscle offers a unique possibility to analyze different bands of the sarcomere in longitudinally cut semithin cryosections. The aim of the present study was to investigate the elemental content of the Z-, I- and A-bands within the sarcomere which may be related to the affinity of an element to different contractile elements and the water content in different bands. The highest potassium levels were found in the Z-band {802 mmol/kg dry weight (d.w.)} as compared to the I-band (697 mmol/kg d.w.) and the A-band (731 mmol/kg d.w.). The difference between A-band and Z-band, …

Effects Of Modulated Microwave And X-Ray Irradiation On The Activity And Distribution Of Ca2+-Atpase In Small Intestine Epithelial Cells, Z. Somosy, G. Thuróczy, G. J. Köteles, J. Kovács

Scanning Microscopy

The distribution and activity of Ca²⁺-ATPase were investigated by histochemical methods in small intestine epithelial cells of mice following total body 2450 MHz low frequency (16 Hz) microwave and X-ray irradiation. In the control animals, enzyme activities were found in the brush border and on lateral membranes, including junctional areas of the cells. The enzyme activity of lateral membranes was inhibited by quercetin, a specific inhibitor of Ca²⁺-ATPase.

Immediately after square modulated (16 Hz) 2450 MHz microwave irradiation at 1 mW/cm² power densities, we observed a decreased activity of Ca²⁺-ATPase on the lateral …

Investigation Of Touch-Sensitive Responses By Hyphae Of The Human Pathogenic Fungus Candida Albicans, N. A. R. Gow, T. H. S. Perera, J. Sherwood-Higham, G. W. Gooday, D. W. Gregory, D. Marshall

Scanning Microscopy

Candida albicans is a fungus that commonly infects the mucosal surface of humans. The hyphal growth form of this fungus may initiate the primary invasion of the host. Here we show that hyphae respond thigmotropically and morphologically to cues such as the presence of a surface, pores, grooves and ridges. Growth on some firm surfaces elicits a helical growth response. Hyphae follow grooves and ridges of inert substrates and penetrate pores of filtration membranes. Our in vitro experiments suggest that thigmotropism may enhance the ability of a hypha to invade epithelia of a host at sites of weakened integrity.

Overlapping Transcription By Rna Polymerases Ii And Iii Of The Xenopus Tfiiia Gene In Somatic Cells, Ernest Martinez, Giorgio Lagna, Robert G. Roeder

Biology

Xenopus TFIIIA gene expression is developmentally regulated. The per cell level of steady-state TFIIIA mRNA present in oocytes is drastically reduced (10(6)-fold) in adult somatic cells, suggesting regulation at the transcriptional level. This is supported by the presence of TFIIIA mRNAs with different 5'-ends in oocytes and in somatic cells, which suggests the presence of distinct cell-/stage-specific promoters, i.e. a strong oocyte-specific and a weak somatic-specific promoter. Here, by mapping the 5'-ends of TFIIIA RNAs found in Xenopus somatic cells, we document the activity not only of an upstream somatic-specific promoter, but also of a down-stream “oocyte-specific” promoter that gives …

Letter To The Editor By M.C. Deruiter And A.C. Gittenberger-De Groot Relating To: "Technical Improvements In Corrosion Casting Of Small Specimens: A Study On Mesonephric Tubules And Vessels Of Chicken Embryos." [By A. Carretero, H. Ditrich, M. Navarro, H. Splechtna, J. Ruberte, Scanning Microscopy Vol. 7(4), P. 1333-1338 (1993)]., M. C. Deruiter, A. C. Gittenberger-De Groot

Scanning Microscopy

Dear Editor,

The topic of scanning electron microscopy (SEM) investigation of casting of vessels in the embryo still holds our interest. We are particularly focused on the possibilities of early injection as a method to support angiogenesis and vasculogenesis research in the embryo. It is questionable whether our technique leads to unreliable results because of severe trauma to the embryo as suggested by the above mentioned authors. The lower success yield might very well be the result of the higher friability of the embryo in general in this young stage.

Neuropeptide Degradation Produces Functional Inactivation In The Crustacean Nervous System, Melissa J. Coleman, P. H. Konstant, B. S. Rothman, Michael P. Nusbaum

WM Keck Science Faculty Papers

The pentapeptide proctolin (Proct.; Arg-Tyr-Leu-Pro-Thr) is a modulatory transmitter found throughout the crustacean nervous system. No information is available in this system, however, as to how the actions of this peptide are terminated. To study this issue in the crab Cancer borealis, we incubated exogenous proctolin (10(-5) M) with either the thoracic ganglion (TG) or with conditioned saline (CS) that had been preincubated with the TG. We removed aliquots at standard time points for analysis by reverse-phase high-performance liquid chromatography (HPLC). We found that over time the proctolin peak became progressively smaller, while three novel peaks appeared and increased in …

Rock Lobster Industry Advisory Commitee Chairman's Report, October 1994 - The Western Rock Lobster Fishery - Management Proposals For The 1994/95 And 1995/96 Seasons, Rock Lobster Industry Advisory Committee, Peter Rogers

Fisheries Management Papers

The failures of past restrictions on fishing effort to fully halt the decline of the breeding stock led to the formation of a sub-committee of the Rock Lobster Industry Advisory Committee. The prime objective of the sub-committee is to evaluate effective long term strategies for managing the fishery so that breeding stock is maintained at an adequate level despite the inevitable increases in catching efficiency. The purpose of this report is firstly to advise industry of the management proposals for the 1994/95 seasons and secondly to form a basis for industry consultation on management arrangements for the 1995/96 season.

Long Term Management Strategies For The Western Rock Lobster Fishery (4 Volumes) - Law Enforcement Considerations (Volume 4), Neil Mclaughlan

Fisheries Management Papers

This report has been prepared for the consideration of the RLIAC Sub Committee in consultation with members of the Sub Committee working group on law enforcement and with senior staff of the Operations Division of the Fisheries Department. It is focussed exclusively on law enforcement issues associated with the management options for the West Australian west coast rock lobster fishery which were under consideration by the Sub Committee at the time of report preparation and should be read in conjunction with Fisheries Management Paper No. 67 entitled "Evaluation of management options" which covers the broader industry management issues. This report …

Long Term Management Strategies For The Western Rock Lobster Fishery (4 Volumes) - A Market-Based Economic Assessment For The Western Rock Lobster Industry (May 1994) (Volume 3), Marec Pty Ltd

Fisheries Management Papers

In October 1992 a special Sub-Committee of the Rock Lobster Industry Advisory Committee was set up to consider and evaluate future management strategies for the rock lobster fishery. Pursuant to this the Director of Fisheries commissioned a marketing study that is the basis of this report. This study was commenced in early October 1993 and completed in May 1994. This study looked at the market implications of fishery's management strategies. In particular it assesses how the existing management structure limits the potential for the lobster industry to maximise the financial return, and in doing so provides an insight into the …