Life Sciences Commons^™

The Analysis Of S-Adenosylmethionine And S-Adenosylhomocysteine In Normal And Neoplastic Cells, Kathryn Elizabeth Godburn

Chemistry & Biochemistry Theses & Dissertations

Altered patterns of methylation have been shown in both ribosomal and transfer RNA isolated from cancer cells. In contrast to the elevated activity of the methyltransferases responsible for this modification, hypomethylation appears as a general characteristic. The endogenous levels of S-adenosylmethionine and S-adenosylhomocysteine are important in relationship to their role as substrate and product of the transmethylation reaction. The levels of S-adenosylmethionine and S-adenosylhomocysteine were determined using phosphocellulose cation exchange or high pressure liquid chromatography. High voltage paper electrophoresis was used in a modified procedure to directly resolve (³⁵s) labeled S-adenosylmethionine and S-adenosylhomocysteine in small quantities of cell …

Sulfatides As Opiate Receptors: An Evaluation Of The Opiate Binding Potential Of Sulfogalactosylgylcerolipid, Darby Geoghegan Hand

Chemistry & Biochemistry Theses & Dissertations

Cerebroside sulfate (CS) has recently been shown to bind opiate drugs in a pharmacologically relevent manner and therefore satisfy the structural requirements of an opiate receptor. Seminolipid (SGG), a novel sulfated galactosyl. glycerolipid that has been isolated from the testes of a variety of mammals, may be viewed as a structural analog of CS. In view of this structural similarity, it is reasonable to presume that SGG may also bind opiate drugs. The isolation of SGG from boar testes was accomplished using silica gel dry column chromotography with a chloroform: methanol water solvent system. The structure and purity of the …

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …

Distribution Of The Dinoflagellate Symbiosis In Astragia Danae As Affected By Light Attenuation, Michael Perry Weston

OES Theses and Dissertations

Spatial zonation of symbiotic and aposymbiotic forms of the temperate coral Astrangia danae provides evidence that light attenuation is an important factor in the distribution of this animal. At four locations in the lower Chesapeake Bay and adjacent offshore waters, symbiotic colonies were observed only in well illuminated surface waters, while aposymbiotic colonies were observed in less illuminated deeper waters. A transition zone exists in which both colony types are found. Colonies on substrates forming a plane parallel to the sea-surface receive a greater radiant flux than colonies on vertical substrates. This extends the depth range of symbiotic colonies located …

The Feasibility Of Commercial Scale Culture Of Atlantic Sturgeon, Acipenser Oxyrhynchus, Christopher John Coffing

Biological Sciences Theses & Dissertations

Abstract unavailable.

Isolation And Enumeration Of Enteric Viruses From Primary Wastewater Sludge, Michael Wayne Nath

Biological Sciences Theses & Dissertations

The presence of large numbers of enteric viruses in wastewaters has resulted in concern regarding their significance and consequences for humans. Assessments of relative significance or consequences may most accurately be made following precise measurements of the range of virus types and amounts in wastewaters and sludges and after epidemiological considerations. In this study, results are presented pertaining to enteric virus isolation, concentration, and enumeration from primary wastewater sludges.

As an integral part of a comparison of isolation procedures, several anionic surfactants were examined for extraction of enteric viruses from primary wastewater sludges. Plaquing efficiencies for poliovirus type 2 and …

Structural Studies Of Preimplantation Rabbit Embryos Using Ftir Atr, Amy R. Moler-Booth

Chemistry & Biochemistry Theses & Dissertations

FTIR was used in conjunction with a surface selective technique, known as attenuated total reflectance (ATR), to study the infrared spectra of preimplantation rabbit embryos. The rabbit embryos ranged in aged from 3 to 6 days. Since an embryo is mostly water, deuteration of the embryo was necessary to eliminate the intense water background present in the mid-infrared region. A set of spectral standards were tested, in order to identify the bands seen in embryo spectra. By analyzing and comparing the spectra from 3, 4, 5 and 6 day embryos, differences could be noted. In particular, bands defined as Amide …

Filtration Ingestion And Assimilation Rates Of The Mysid Shrimp Neomysis Americana Smith, Fed Three Food Sources, Robert W. Grabb

OES Theses and Dissertations

Laboratory grazing and assimilation experiments were conducted on the mysid shrimp Neomysis americana in an attempt to assess the suitability of three potential food sources. It was hypothesized that the smaller size classes were primarily herbivores, not becoming omnivorous until attaining lengths of approximately 5-6 mm. Four size classes of mysids from the summer generation, juveniles, immature, adult males, and adult ovigerous females were each fed three concentrations of Artemia salina nauplii, the rotifer Brachionus plicatilis, and the diatom Coscinodiscus lineatus. The mean lengths of the size classes utilized, plus or minus one standard deviation, were 2.5 …

Aspects Of Larval Ecology Of Squilla Empusa (Crustacea, Stomatopoda) In Chesapeake Bay, Steven G. Morgan

OES Faculty Publications

Larvae of Squilla empusa were collected from the plankton and were laboratory-reared in 16 combinations of temperature and salinity to determine their tolerances. Larvae survived longer and molted more frequently when reared at 25%, and 20° or 25° C, which corresponds to the natural conditions of Chesapeake Bay when the larvae were collected.

A 2 year planktonic survey conducted in the lower region of the bay by the Virginia Institute of Marine Sciences was compared with a survey made at the bay mouth in 1976. The seasonal occurrence of Squilla empusa larvae extended from the last week of July until …

Phytoplankton Studies Within The Virginia Barrier Islands I. Seasonal Study Of Phytoplankton In Goose Lake, Parramore Island, Harold G. Marshall

Biological Sciences Faculty Publications

The phytoplankton of Goose Lake, an oligohaline lake on Parramore Island, was studied for one year. The populations consisted primarily of ultraplankton and nanoplankton-sized forms with diatoms and chlorophyceans dominant most of the year. A general pattern of seasonally higher cell concentrations in early summer and fall was noted, with an unidentified ultraplankton-sized component prominent throughout the collection period. A list of 154 species is given.

The Association Of 5.8 S With 28s Ribosomal Rna, Nandita Banerjee

Chemistry & Biochemistry Theses & Dissertations

5.8S rRNA is a low molecular weight ribosomal RNA which is noncovalently bonded to the larger ribosomal subunit 28S rRNA; through its 3' end and through its 5' end. This interaction is an integral part of the ribosome, and plays an important role in the ribosome structure and function.

There is a high degree of homology between the 5.8S rRNA primary structures of rat, turtle and chicken. The base sequence of rat 5.8S rRNA differs only in one position from that of turtle and in three positions fr.om that of cl1.icken. Tl1ere is a single purine substitution at the 5' …

Multiple Methods Of Analysis Of 2'-O-Methylation In 5.8s Rrna, Sharon H. Ryan

Chemistry & Biochemistry Theses & Dissertations

5.8S rRNA is a low molecular weight ribosomal RNA which is found hydrogen bonded to 28S rRNA in the eucaryotic cell. There are two nucleotides which have 2'-0-methylations; a guanine residue at position 77 is fully methylated and a uridine residue at position 14 which is partially methylated. This partial 2'-0-methylation of the uridine residue has been found to vary with the tissue source, with the highest level in normal tissue and the lowest level in neoplastic tissue. In order to study the significance of this site-specific methylation, a reliable and convenient method of analysis was needed.

Early studies on …

Morphological Variation Among 14 Species Of Callogobius Bleeker (Pisces: Gobiidae), James Francis Mckinney

Biological Sciences Theses & Dissertations

A survey of the variation among the species of the Callogobius complex has been accomplished in order to determine if recognition of more than one genus is warranted for this assemblage of species. Emphasis has been placed on the osteological variation. Relationships among certain species within the Callogobius complex have been exposed. Although there are two well defined species groups within the complex, it is felt that inclusion of all of the examined species within the single genus Callogobius is the most parsimonious course of action.

Structure Of A Subtidal Benthic Community Near Cape Charles, Virginia, R. Michael Ewing

Biological Sciences Theses & Dissertations

Species composition, distribution, and abundance of benthic invertebrates of a subtidal community were examined at a location on the lower Delmarva Peninsula near Cape Charles, Virginia. Macrobenthos was sampled quarterly between June, 1977 and June, 1978 at nine sites along a transect in Old Plantation Creek and the adjacent offshore area. Spatial and temporal patterns of numerically important species are discussed.

Sampling sites and species were grouped by a numerical classification strategy which consisted of the Bray-Curtis similarity measure and group-average clustering. Three faunal assemblages were identified with the aid of constancy and fidelity nodal analyses: (1) a tidal creek …

The Synthesis And Evaluation Of The Potential Antineoplastic Activity Of The Semicarbazone And The Thiosemicarbazone Derivatives Of The Di-2-Pyridyl Ketone And The 1,8-Diazafluorenone Ring Systems, Adriene Y. Principe

Chemistry & Biochemistry Theses & Dissertations

A number of' a-(N)-heterocyclic thiosemicarbazones have been synthesized and evaluated for potential antineoplastic activity since Brockman and colleagues2 reported the antineoplastic activity of' 2-f'ormylpyridine thiosemicarbazone (1). The primary objective of' this research project has been the synthesis and characterization of' the semicarbazone and the thiosemicarbazone derivatives of' the di-2-pyridyl ketone, (9-a) and (9-b), and the 1,8-diazaf'luorenone, (10-a) and (10-b), ring systems, as well as the evaluation of' these compounds for both in vitro and in vivo antineoplastic activity against Ehrlich ascites tumor cells in mice. These studies have suggested that di-2-pyridyl ketone thiosemicarbazone (9-b) is as effective as 2-formylpyridine …

The Development Of Techniques For The Enumeration Of Selected Pathogenic Bacteria In Lynnhaven Estuarine Sediments, Mark T. Frank

Biological Sciences Theses & Dissertations

Methodologies for the improved recovery of selected pathogenic bacteria from estuarine sediments were investigated. Laboratory and field studies were conducted to document the sensitivity of the techniques for isolating Salmonella species, Pseudomonas aeruginosa, and Vibrio parahaemolyticus. Vibrio parahaemolyticus-like organisms were enriched in a seawater yeast extract broth and isolated from Thiosulfate Citrate Bile Salts Sucrose plated media. Enrichment procedures with and without elevated temperatures and subsequent transfers to selective and differential plated media have been examined for the isolation of Salmonella species and P. aeruginosa. These pathogens were initially assayed for utilizing primary enrichments of asparagine …

Detection Of Unique Tumor-Associated Proteins In The Urine Of Patients With Transitional Cell Carcinoma By High Resolution Two-Dimensional Polyacrylamide Gel Electrophoresis, Robert David Lehman

Biological Sciences Theses & Dissertations

A two-dimensional polyacrylamide gel electrophoretic technique was developed for the detection of unique tumor-associated proteins in urine of patients with transitional cell carcinoma (TCC) of the urinary bladder. This technique yielded high resolution of polypeptides in the urine of cancer patients. Urine was chosen as a source of tumor-associated components because the location of the tum or should release already solublized tum or substances in to the urine.

Urinary proteins were concentrated and then analyzed by the two - dimensional electrophoretic technique using isoelectric focusing in the first dimension and sodium dodecylsulfate - polyacrylamide gel electrophoresis in the second dimension. …

Swimming As A Determinate To Immigration For Two Small Mammals In Coastal Virginia, Jeffrey Lewis Carter

Biological Sciences Theses & Dissertations

Small mammals were live trapped on the mainland and on an island located in the southeast corner of Virginia. The area was characterized by a mid-Atlantic coastal climate. White-footed mice (Perompsous fsucopus) were trapped on the mainland but not on the island, whereas meadow voles (Microtus psnnsylvimious) inhabited only the island. A series of swimming tests were performed in both the field and in the laboratory on both of these species to determine if swimming abilities could be the factor preventing Pszomysous from colonizing the island.

Both species of small mammals showed good swimming endurance in …

Studies On The Anatomy Of The Parasitic Gymnosperm Parasitaxus Ustus (Podocarpaceaea), Evelyn Wilkinson

Biological Sciences Theses & Dissertations

An anatomical study of the parasitic gymnosperm Parasitaxus ustus was conducted. Material was collected in New Caledonia, embedded in paraffin or celloidin, sectioned and stained. The apical meristem consists of apical initial cells, central mother cells, the peripheral zone, and rib meristem. Leaves are scale-like, triangular and broadly decurrent at their bases. Resin ducts and prominent sclereids are present in leaves and the cortex of the stem. The parasite-host connection is in the form of a xylem to xylem connection in which the tracheids are connected by bordered pits.

Feeding Morphologies And Distribution Patterns Of Marine Cladocera In The Lower Chesapeake Bay, Sandra Layne Gilchrist

OES Theses and Dissertations

Temporal and spatial distributions of marine cladocera in the lower Chesapeake Bay estuary were observed over a year-long sampling period. The distributions of cladoceran species throughout the Bay were studied in relation to temperature and salinity. A survey of the species over the entire Bay is included to establish distribution patterns of the various species during a short time period.

Theoretical mathematical principles were used to predict feeding abilities of the Bay species. Mouthparts are described qualitatively and quantitatively to infer function. A mandibular index developed by Itoh (1970) was revised and employed in evaluating feeding methods interspecifically and interspecifically. …

The Spatial And Temporal Distribution Of Fish Eggs And Larvae In Hempstead Bay Estuary, Joseph Adelard Lessard

OES Theses and Dissertations

The ichthyoplankton of Hempstead Bay estuary was sampled from December 1972 to mid March 1974. Eleven stations were sampled by towing a 0.5 meter diameter plankton net. Eggs were most abundant during June and July with an average concentration calculated to be above 5,500/100m³. Egg densities were the lowest during the fall and winter. Larvae were most frequently taken from March through July with densities varying greatly among the samples. The eggs of Brevoortia tyrannus, Anchoa mitchilli, Tautoga onitis, Tautogolabrus adspersus, and Scophthalmus aguosus and the larvae of Menidia menidia, Ammodvtes hexapterus and Pseudopleuronectes americanus constituted most …

Seasonal Feeding Habits Of The River Otter (Lutra Canadensis) In Ditches Of The Great Dismal Swamp, Ronnie M. Pierce

Biological Sciences Theses & Dissertations

To determine the seasonal feeding habits of the river otter (Lutra canadensis) in the Great Dismal Swamp 209 scats were collected, from May 1977 to May 1978, and analyzed for content. Remains of crayfish were found with a frequency of occurrence of 82% while fish remains occurred in 62% of the scat. This is in direct contrast to previous studies (from other areas) which found fish with a greater frequency than crayfish. Fish consumption was believed to increase during periods of low water or low temperatures. Sunfish were represented most frequently and may be the preferred fish. Amphiuma remains …

Additional Comments On Reproductive Strategies And Population Fluctuations In Microtine Rodents, Michael S. Gaines, William M. Schaffer, Robert K. Rose

Biological Sciences Faculty Publications

Recently, Schaffer and Tamarin (1973) proposed a model relating changes in reproductive effort (RE) to fluctuating densities in microtine rodents (lemmings and voles). They assumed (and presented data supporting this assumption) that the major effect of increased crowding would be a reduction in survival among prereproductives, thereby lowering the effective fecundity (Schaffer and Rosenzweig 1977) of their parents. As a consequence, Schaffer and Tamarin argued that the optimal reproductive expenditure, E(N), should decline with increasing population size, N. They also deduced the shape of the zero-growth isocline, N*(E), for differing levels of RE and plotted both E(N) and N*(E) on …

Development Of Pelagic Larvae And Postlarva Of Squilla Empusa (Crustacea, Stomatopoda), With An Assessment Of Larval Characters Within The Squillidae, Steven G. Morgan, Anthony J. Provenzano Jr.

OES Faculty Publications

Larvae of the predatory crustacean Squilla empusa were collected from the plankton in Chesapeake Bay and reared in the laboratory to permit description of the pelagic stages before the postlarval stage.

Characters such as rostral length and spinulation, carapace spinulation, relative size of telson, overall body size, and appearance probably are of more value for specific than for generic identification. The presence or absence of teeth on the dactylus of the second maxilliped, the presence or absence of a spine on the basis of the second maxilliped, and the number of epipods may be useful characters in determining generic alliances …

A Potential Macroregulatory Mechanism For Growth Regulation In Neurospora Crassa, Martha Mooney

Biological Sciences Theses & Dissertations

Neurospora produces a phase specific, cationic mucopolysaccharide composed primarily of galactosamine (GAG-MP) which becomes part of the cell wall and is later secreted into the media. Its appearance coincides with the onset of the restricted phase of growth and causes efflux of small molecular weight metabolites when incubated with conidial cells. This activity may be a product of electrostatic interactions of the GAG-MP with the conidial plasma membrane. The activity is blocked by acetylation of the primary amines on the molecule, digestion by enzymes that hydrolyze carbohydrate linkages and the inclusion of NaCl (lM) in the GAG-MP/conidia reaction mixture. The …

Animal-Sediment Relationship Study Of The Western Branch Of The Lynnhaven River, Charles Perry Seymour

Biological Sciences Theses & Dissertations

The animal-sediment relationships of the marine benthic infauna of an estuarine river system, Lynnhaven River, Virginia Beach, Virginia, were studied at six sites, sampled bimonthly for one year. Six species were found to dominate all of the sampling periods and sites for the year. The greatest number of individuals, biomass, and species were found at the sand sites. Deposit feeders were recorded in greater number than suspension feeders at both the sand and the mud sites.

Cluster and nodal analyses were successful in demonstrating animal-sediment relationships for the intertidal regions of the river system.

The Fall And Winter Food Habits Of The Black Bear (Ursus Americanus) In The Great Dismal Swamp Of Virginia, Francis Leonard Daniel

Biological Sciences Theses & Dissertations

A study was conducted on the food habits of the black bear (Ursus americanus) in the Great Dismal Swamp of Virginia. A total of four stomachs and 42 scats were analyzed. Four samples were collected from September and October of 1975, and the remainder of the samples were collected from September 1976 to February 1977. The study was conducted to obtain information vital to the management of this species in the Great Dismal Swamp. Vitis spp. was the primary food item during the fall comprising 43% of the total diet, followed by fruits of Diospyros virginiana and Asimina triloba, each …

Mercury, Copper, And Zinc In Selected Ichthyofauna Of Lower Chesapeake Bay And Hampton Roads, Virginia, W. Bruce Aitenhead

OES Theses and Dissertations

Anchovys, croaker, spat, summer flounder and hogchokers were collected monthly to seasonally from November 1972 to October 1973 at three locations in the southern Chesapeake Bay region of Virginia.

The concentrations of mercury, copper and zinc were determined by atomic absorption spectrophotometry in whole fishes. Metal concentration varied with species and location. Anchovys had the highest mean concentrations of mercury and zinc while hog- chokers had the highest mean copper concentration. Mercury levels exceeding O.5 ppm were observed in species from all three loca- tions, but maximum heavy metal concentrations per species were highest in Craney Island fishes.

Temporal variations …

Herbaceous Production In Burned-Cut Burned-Uncut And Control Areas Of A Chamaecyparis Thyoides (L.) Bsp (Cupressaceae) Stand In The Great Dismal Swamp, Caroline Elisabeth Mckinley

Biological Sciences Theses & Dissertations

The herbaceous layer of an Atlantic white cedar (Chamaecyparis thyoides) stand in the Great Dismal Swamp was sampled to estimate the productivity of two burned areas and a control area. The herbaceous vegetation was sampled along three transects utilizing the harvest method and productivity values were estimated using peak biomass values for each individual species. The burned-cut area had the highest productivity (3623 kg ha^-l yr^-1) and was characterized by species of the Asteraceae, Poaceae, and Cyperaceae. The burned-uncut area had a productivity value of 1636 kg ha^-1 yr^-1 with similar species of the Asteraceae …

The Photosynthetic Action Spectra Of The Phytoplankton And Their Role In Governing Spatial And Temporal Distribution: A Numerical Modeling Approach, William Morrow Willis

OES Theses and Dissertations

In the present study a numerical modeling approach is employed to examine the role of division spedific differences in photosynthetic action spectra in governing the relative size of diatom and dinoflagellate carbon synthesis along various marine light regime gradients. A radiative transfer model taking into account both Rayleigh and Mie atmospheric optical properties is employed to define the light regime incident on the sea surface. The hydrospheric light regime is defined by an exponential decay model with a correction for diffuse back scatter. Taken together, the atmospheric and hydrospheric models define the spectral composition and intensity of light in the …