Physiology Commons^™

Effect Of Dietary Factors On Mutagenesis, Metabolism, And Binding To Dna Of Benzo [A] Pyrene And Benzo [A] Pyrene 7, 8-Dihydrodiol, Robin E. Vance

Loma Linda University Electronic Theses, Dissertations & Projects

Ellagic acid (EA), a naturally occurring plant phenol, at concentrations of 5 to 50 pg/plate, inhibited rat liver S9 protein dependent benzo[a]pyrene (B[a]P)-induced mutagenesis in Salmonella typhimurium TA 100 by 30-81% and B[a]P 7,8-dihydrodiol (DHD)-induced mutagenesis by 29 to 75%. EA (5-40 juM) did not significantly affect the metabolism of B[a]P or B[a]P 7,8-DHD as determined by high performance liquid chromatographic analysis of the organosoluble fraction and by the quantification of watersoluble conjugates. At these concentrations EA inhibited 3 3 the covalent binding of [ H] B[a]P and [ H] B[a]P 7,8-DHD metabolites to calf thymus DNA by 5 to …

The Prenatal Development Of The "Synaptic" Structures In The Guinea Pig Pineal Gland, Zhongrong Luo

Loma Linda University Electronic Theses, Dissertations & Projects

Pineal "synaptic" ribbons are a heterogeneous population of organelles. In addition to "synaptic" ribbons (SR) sensu stricto, which are electron-dense rods, "synaptic" spherules (SS) and intermediate forms (IMF) are present. The SS are electron-dense spherical structures, the diameter of which is two to three times the width of the SR. The IMF appear as irregularly formed structures. The SR, SS and IMF are surrounded by electron-lucent vesicles. Their function and origin are unknown and also a knowledge of their prenatal development is lacking. In order to gain an insight into the development of the "synaptic structures, the pineal glands …

Full Issue, Vol. 12

Great Basin Naturalist Memoirs

No abstract provided.

End Matter, Vol. 12, Index

Great Basin Naturalist Memoirs

No abstract provided.

Front Matter, Vol. 12

Great Basin Naturalist Memoirs

No abstract provided.

End Matter, Vol. 12

Great Basin Naturalist Memoirs

No abstract provided.

Age-Related Changes In Meissner Corpuscles Of Diabetic Mice As Observed By Electron Microscopy, Vicky R. Ras

Loma Linda University Electronic Theses, Dissertations & Projects

Light touch and low-frequency vibration sense are often impaired in diabetic patients. Meissner corpuscles are distally located mechanoreceptors that respond to these stimuli. Peripheral sensory neuropathy in diabetes progresses from distal to proximal, therefore, Meissner corpuscles are ideally suited to study diabetic neuropathy in the C57BL/Ks (db/db) mouse.

Corpuscles from the forepaw digital pads of 9 diabetic and 9 nondiabetic littermates were studied by electron microscopy. These were divided into 3 age groups; 2.5 months, 10 months, and 17 months old.

Ultrastructural changes observed within various receptor components were myelin figures, multivesicular bodies, vacuoles, basal lamina duplication, abnormal and enlarged …

An Analysis Of Protein-Ligand Interactions For Enzyme Ii-Mannitol From Escherichia Coli, Brent Lee Wood

Loma Linda University Electronic Theses, Dissertations & Projects

Enzyme II^mtl of Escherichia coli was purified from mtlA-overexpressing E. coli strain LJ1112 extraction of isolated membranes with deoxycholate, followed by hexyl agarose and ω-amino hexyl agarose chromatography in Lubrol PX. A 10-fold increase in total pure protein and 2.5-fold increase in specific activity over previously reported procedures was obtained. Tryptic fragments of Enzyme II^mtl were also purified and identified as the membrane and cytoplasmic domains by protein sequencing and SDS-PAGE. The fluorescence spectrum of Enzyme II^mtl suggested that two populations of tryptophan residues existed with emission maxima at 322 and 344 nm, corresponding to buried …

Computer Analysis Of Cross Sections Of Leaves Of Chrysothamnus Taxa And Their Relation To Environmental Conditions, J. Huang, W. M. Hess, D. J. Weber, E. D. Mcarthur, S. E. Meyer, R. Seegmiller

Great Basin Naturalist

Thirty-eight accessions of 20 taxa (species and subspecies) of Chrysothamnus from a range of environments were grown in a uniform garden. During mid-June, terminal and lateral leaves were removed, fixed, and processed for light-microscopy studies. Area and perimeter measurements of ink tracings of midleaf vein cross sections were measured using computer-scan techniques. Leaf area and perimeter were compared with vein perimeter and area measurements. Area and perimeter of these Chrysothamnus leaves varied in response to the environment at the collection location. Plants native to hot, dry conditions had small, thick leaves, whereas plants native to cooler, more mesic conditions had …

A Descriptive Catalog Of Dimming Cells In The Purple Shore Crab Hemigrapsus Nudus, Eugene Pak

Loma Linda University Electronic Theses, Dissertations & Projects

A population of cells responsive to the decrease or dimming of light was identified in the Purple shore crab Hemigrapsus nudus. Extracellular pin electrode recordings from the optic nerve tract measured responses to decremental changes in relative light levels over the range 40 to 0.08 lux. The observed activity revealed that these dimming cells could respond over this entire range. A catalog detailing the response characteristics for each of the thirty dimming cells in the study was generated. The parameters measured the receptive field size; response to mechanoreceptive tactile stimuli; response to abrupt On or Off light level changes; …

Effects Of Graded And Steady Exercise And Self-Confidence On Stress, Kristine M. Clarke

Dissertations and Theses

This study examined the effects of steady, graded, and no exercise on stress reduction, and the effects of self-confidence on stress reduction through exercise. Seventy-two male and female volunteers from the Portland area, ranging in age from 19-49 years, served as subjects. Subjects completed pre and post measures of the Tennessee Self-Concept Scale and the state portion of the Spielberger State-Trait Anxiety Inventory. Subjects were divided into two experimental and one control group matched according to age and exercise history. The control group kept its exercise at a minimum for eight weeks. Exercise programs for the two experimental groups consisted …

Skeletal Muscle Sugar Transport Alterations In Bacteremia, Margaret V. Westfall

Dissertations

No abstract provided.

Age Differences In Bimanual Coordination, Paul Amrhein, George Stelmach, Noreen Goggin

Department of Psychology Faculty Scholarship and Creative Works

A bimanual coordination experiment was conducted in which two groups of 10 male and female participants, elderly (67 to 75 years of age) and young (21 to 25 years of age), produced unimanual, bimanual symmetrical (equal extent amplitude), and bimanual asymmetrical (unequal extent amplitude) movements. In addition to an overall increase in performance latency, the elderly group exhibited a linear increase in response initiation (RT) with increases in task complexity similar to that of the young group. However, the elderly participants showed a proportional increase over the young participants in response execution latency (MT). Further, the elderly group had a …

A Model For Evaluating Time Constraints On Short-Term Reproductive Success In Altricial Birds1, Larry Clark

Larry Clark

We develop a simple single dimension model incorporating the time and energy commitments of breeding altricial birds in an effort to understand the evolutionary constraints on parental care. We chose time as the dimension of preference, because it is a naturally bounded constraint, e.g., length of day or breeding season. The utility of the model was evaluated by comparing simulations of time allocation of various breeding scenarios for the European starling (Sturnus vulgaris) to field data. The structure of the model may prove useful in determining the evolutionary constraints on parental care imposed by the developmental pattern of chicks.

Incubation Energetics Of The Laysan Albatross, Ted N. Pettit, K A. Nagy, Hugh I. Ellis, G Causey Whittow

Biology: Faculty Scholarship

The energy expenditure of incubating and foraging Laysan Albatross (Diomedea immutabilis, mean body weight 3.07 kg) was estimated by means of the doubly-la- belled water technique. During incubation, the energy expenditure was similar to that of resting birds that were not incubating an egg. The energy expenditure of foraging albatross (2072 kJ/day) was 2.6 times that of resting birds. It was concluded that the energy expenditure of the tropical Laysan Albatross was not less than that of species foraging over cold, high-latitude oceans. An energy budget compiled for an incubating pair of albatross revealed that the energy expenditure of the …

The Relationship Of Free And Total Serum Thyroxine Concentrations To The Reproductive Condition Of The White-Footed Mouse (Peromyscus Leucopus Noveboracensis), Gerald William Peden

Dissertations, Theses, and Masters Projects

No abstract provided.

Correlations Between Serum Corticosterone Level And Reproductive Fitness In Laboratory Populations Of The White-Footed Mouse (Peromyscus Leucopus Noveboracensis), Sterling Neblett Ransone

Dissertations, Theses, and Masters Projects

No abstract provided.

The Effect Of Caloric Restriction And Exercise On Plasma Lipid And Lipoprotein Concentration, Jeffrey J. Zachwieja

Masters Theses

The independent and combined effects of exercise training and caloric restriction on the plasma concentration of lipid and lipoprotein was studied. Thirty-two female volunteers were assigned to one of three treatment groups; exercise only, diet only or diet plus exercise. The exercise only group participated in a walk/jog program three days per week. For 30 to 45 minutes these individuals either walked or jogged at a intensity which elicited a heart rate that was 70% of the max heart rate reserve. The diet only group participated in a behavior modification weight loss program which restricted caloric intake to 1200 kcals …

Steady State Oxygen Cost Of Arm Ergometry Using The Monark Rehab Trainer, Gregory R. Grazen

Masters Theses

This study was designed to determine the steady state oxygen cost of arm crank ergometry with the Monark Rehab Trainer, a device used for exercise training in many cardiac rehabilitation programs. Fifteen male (25.2 yrs. ± 4.1) and fifteen female (23.8 yrs. ± 4.0) subjects were tested in the seated position with the mid-point of the crank wheel adjusted to shoulder height. No attempt was made to stabilize the shoulder girdle, as this is typically not done when training with this device. The test protocol for both groups consisted of progressive three minute work stages followed by a thirty second …

Influx, Net Flux And Transepithelial Flux Of Amino Acids In The Hardshell Clam Mercenaria Mercenaria (Linne): Influence Of Salinity, Michael Rice, Grover Stephens

Michael A Rice

1.1. The effects of salinity on the uptake and internal distribution of alanine and other free amino acids (FAA) in hardsell clams, Mercenaria, was studied by radiochemical and high performance liquid chromatography (HPLC) techniques.2.2. Exposure of animals to reduced salinity does not alter the rate of unidirectional alanine influx.3.3. In 34%o salinity, entry of labeled alanine reflects the net flux of the amino acid. However, in 17%o salinity, there is a net loss of alanine and other acids, mainly taurine, to the medium.4.4. Reduced salinity induces greater incorporation of radiolabeled FAA into macromolecular fractions throughout the animal.5.5. The major factors …

Influx And Transepithelial Flux Of Amino Acids In The Mussel, Mytilus Edulis., Michael A. Rice, Grover C. Stephens

Michael A Rice

The uptake of amino acids by the non-gill epithelia of the mantle cavity of Mytilus edulis L. was studied and compared with uptake by the gills. Amino acid entry rates and the subsequent distribution of amino acids to the other tissues of the animals were studied using high-performance liquid chromatography and radiochemical techniques. Uptake via the non-gill epithelia lining the mantle cavity was separated from uptake via the gill by employing a preparation in which the gills were surgically removed. Amino acid uptake by such animals was compared with that of suitably sham-operated controls. In short-term experiments (up to 2h), …