Oxidative stress is the major driving force behind the aging process and many age-related diseases. However, direct experimental evidence of whether antioxidants, such as ascorbate (AA) and lipoic acid (LA) can slow the progression of aging process and/or reduce risks of developing degenerative disease is largely absent. This suggests a...
Plethodontid salamanders have served as an informative vertebrate system for studying the role of chemical signals in facilitating social and reproductive behaviors. Individuals produce complex mixtures of chemicals from multiple glandular regions. In total, these secretions convey a wide variety of information, and are important for numerous inter- and intraspecific...
Concentrations of twenty-five PCBs, fifteen organochiorine pesticides and mercury were determined in recreational fish from the Willamette River, Oregon during the summer of 2000. Thirty-six fish samples of three fish species including black crappie, smalimouth bass and con-rn-ion carp were analyzed. The data reported here provides new information and recent...
This study was undertaken to determine if strontium chloride could be used to create a trans-generational otolith mark in steelhead (Oncorhynchus mykiss). I completed two strontium injection trials and a survey of juvenile steelhead from various steelhead hatcheries. The two trials measured Sr:Ca ratios in otoliths in response to injections...
Female athletes exhibit three- to six-fold greater incidence of noncontact anterior cruciate ligament (ACL) injury relative to their male counterparts. The increased risk appears to stem from interactions between several risk factors, that can roughly be categorized as anatomic, biomechanical, hormonal, and neuromuscular. Neuromuscular risk factors have recently gained a...
A significant body of research demonstrates that phytochemical intake favorably influences hepatic metabolism via a number of different biological mechanisms. Other research has shown a positive effect of certain phytochemicals on kidney health, specifically in ameliorating symptoms of kidney disease. The current research used three separate studies that tested the...
Peroxiredoxin (Prx) enzymes catalyze the reduction of hydrogen peroxide, peroxynitrous acid, and organic peroxides, and are extremely efficient peroxidases, with k[subscript cat]/K[subscript M] on the order of 10⁷ - 10⁸ M⁻¹ s⁻¹. Besides their role in oxidative stress defense, evidence has accumulated that some eukaryotes, including humans, use Prxs as...
The Fukushima Daiichi nuclear disaster of 2011 made it apparent that releases of fission products to marine environments is a very real possibility. Additional data on the movement of material through marine environments can be used by radioecology personnel to assist with both ecosystem protection as well as environmental cleanup...
Ozone is recognized as one of the most dangerous irritants to eyes, throat, lungs and etc .. Chamber studies consistently have demonstrated adverse effects of ozone on human lung function. The results of epidemiological studies, however, have been controversial, partly because there are many factors that affect human lung function....
We have previously shown that diets enriched with (n-3) fatty acids reduced the delayed-type hypersensitivity (DTH) skin reaction to keyhole limpet haemocyanin (KLH) in geriatric-Beagles. Although the amount of α-tocopheryl acetate in diets of the previous study exceeded requirements, plasma α-tocopherol concentration was significantly lower in dogs fed the high...
The public controversy over possible health hazards from radioactive fallout from atomic bomb testing began in 1954, shortly after a thermonuclear test by the United States spread fallout world wide. In the dissertation, I address two of the fundamental questions of the fallout controversy: Was there a threshold of radiation...
Previous studies have shown that rainbow trout exposed to dieldrin via diet for 9 to 12 weeks increased biliary excretion of a subsequent dose of [¹⁴C]dieldrin by 500%. This was not explained by induction of the cytochrome P-450 (CYP) system involved in oxidative metabolism of these compounds. We hypothesized that...
Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM), a primary I3C
derivative in vivo, are known chemopreventive agents available as dietary supplements.
I3C was found to suppress or enhance tumors in several animal models.
Chemoprotection is attributed to the ability of indoles to alter carcinogen metabolism
effectively blocking initiation. However, mechanisms for enhancement...
Three experiments compared ruminal, physiological, and performance responses of beef steers consuming hay ad libitum and receiving grain-based supplements with (CAM) or without (CO) inclusion of camelina meal. In Exp. 1, 9 steers fitted with ruminal cannulas received CAM (2.04 kg of DM/d) or CO (2.20 kg of DM/d). Steers...
The present study investigated whether vitamin E supplementation reduced oxidative stress in erythrocytes and improved vitamin E status in patients undergoing hemodialysis (HD). Plasma and erythrocyte α-tocopherol, plasma ascorbic acid, and iron status were determined in 11 regular HD patients prior to and post-dialysis, before and during oral supplementation of...
Epidemiological studies have suggested that the consumption
of fish may reduce the risk of cardiovascular disease.
Compared to the number of studies using fish oils, few
studies have used fish itself. Those which have used fish
have generally used fattier fish such as mackerel and salmon
as part of an...
Two studies were conducted to determine the effect of varying vitamin B-6 (B- 6) status on lymphocyte mitogenic response and pyridoxal 5'-phosphate (PLP) concentration in peripheral blood mononuclear cells (PBMC) in young women. In the first study, women were fed 1 mg/d for the first week and 1.5, 2.1 and...
Twenty-one women, lifelong residents of Xichang County, Sichuan Province, China, an area of very low soil selenium (Se), received tablets containing either 100 μg Se daily as Se-enriched yeast (+Se) or no additional Se (-Se), throughout the last trimester of pregnancy and the first three months of lactation. Diet was...
There have been several epidemiological studies linking alcohol
consumption to a decreased risk of contracting illness from foodborne
bacterial contamination. To study this phenomenon, we examined the
survival of Escherichia coli 0157:H7 and Salmonella typhimurium in grape
juice and wine and then designed a model stomach to investigate the effect...
Microbial lethality is strongly pH dependent in processing regimes including
high hydrostatic pressure processing (HPP). HPP induces the dissociation of
weak acids that potentially causes a shift in pH in some systems thereby increasing
acidity while pressure insensitive buffers do not undergo dissociation. The
degree of high pressure induced pH...
The surface tension kin'ti4tnd ste'dy state behavior exhibited by mixtures of selected
surfactants with a recombinant Factor VIII (rFVIII) were evaluated with automated
interfacial tensiometry. In particular, fresh solutions of rFVIII with different concentrations
of Tween 80, sodium dodecylsulfate (SDS), or dodecyltrimethylammonium bromide
(DTAB) were prepared and their surface tension...
This research explores the viability and effectiveness of using an inertial navigation system (INS) to control a beamforming array of microstrip patch antennas with the aim of reducing users' exposure to electromagnetic radiation. The system reduces radiated power directed toward a cellular phone user to below 10% of the total...
This dissertation presents a research series demonstrating the use of pharmacokinetic modeling and simulations as tools to assess drug concentration and disposition in patient populations. For drugs requiring therapeutic drug monitoring, these tools are necessary to ensure patients are receiving a safe and effective dose of medication to address their...
This report presents progress accomplished during the 20-month period from 1 July 1972 through 31 March 1974 as part of the program "Ecological Studies of Radioactivity in the Columbia River Estuary and Adjacent Pacific Ocean". This program is a continuing study supported by the Division of Biomedical and Environmental Research...
Calcium activated proteases, or calpains, are activated in cardiac muscles under conditions of ischemia/reperfusion and hypoxia. Their activity in skeletal muscle under similar conditions is poorly understood. We tested the hypothesis that hypoxia elevates calpain-mediated proteolysis in isolated glycolytic (extensor digitorum longus, EDL) and oxidative (soleus, SOL) mouse muscles studied...
Nares Strait is one of three main passages of the Canadian Archipelago that
channels freshwater from the Arctic Ocean to the North Atlantic. There are very few
observations regarding the role of this region on the present day Arctic freshwater budget,
and even less regarding the changes in freshwater fluxes...
This summary discusses the risk to human health associated with herbicide
application projects to control noxious weeds and poisonous plants on lands
administered by the USDA Forest Service in the Northern Region. The Northe!n
Region consists of approximately 211.8 million acres of National Forest System
(NFS) land in northern Idaho,...
Two strains of Escherichia coli were studied to determine the effect of constitutive expression of the SOS DNA damage repair response on the activity of ribonucleotide reductase. Activity of the reductase and cellular deoxynucleoside triphosphate (dNTP) pools were both determined before and after exposure of the cells to ultraviolet radiation....
We hypothesized that calpain activity is elevated in response to muscle damage. To test this hypothesis, we examined the degradation of α-fodrin into its 150 and 145 kDa fragments following either 20 eccentric or isometric contractions. In addition, experiments were performed in the presence or absence of E-64-d, a calpain...
The following experiment presented herein compared growth, physical activity, stress-related responses, and puberty attainment in heifers reared on high- (HIDENS) or low-stocking densities (LOWDENS). Sixty Angus x Hereford heifers were ranked by age and BW (210 ± 2 d and 220 ± 2 kg, respectively) on d 0, and assigned...
The symbiosis between cnidarians, such as corals and sea anemones, and photosynthetic dinoflagellates belonging to the genus Symbiodinium spp. is one of the most productive in the marine environment. This mutualistic endosymbiosis allow reef-building corals to lay down the foundation of coral reef ecosystems, which supports a highly biodiverse community...
We investigated the relationship between calcium and protein intake and bone loss over a one-year period in 99 early postmenopausal women (1-36 months) aged 51.3 ± 0.31 years. Bone mineral density (g/cm²) of the left hip (total hip, femoral neck, greater trochanter) and lumbar spine (L1-L4) as well as body...
Oceanic uptake of rising anthropogenic CO₂ emissions has caused the emergence of ocean acidification as a major threat to marine ecosystems worldwide. Along eastern boundary current systems, seawater is naturally acidified due to coastal upwelling of low pH seawater from depth. Compounded by ocean acidification, upwelling regions are expected to...
The objective of this work is to add to the body of translational data between high dose animal model research and the environmentally relevant human metabolism of the persistent pollutant dibenzo[def,p]chrysene (DBC). We furthered the knowledge of gene/exposure interactions by determining the carcinogenesis risk based on Cyp1b1 genotype following in...
Melanoma is the deadliest form of skin cancer, arising from malignant transformation of pigment-producing melanocytes. The primary risk factor for melanoma and other skin cancers is DNA damage resulting from unprotected solar ultraviolet radiation (UVR). If incorrectly repaired, this damage can result in incorporation of mutations that cause aberrant cell...
Postmenopausat women on hormone replacement therapy (HRT) have been reported to be stronger when compared to women who are not using HRT. The first goal of this study was to investigate whether muscle morphology was altered in women who use HRT when compared to women who do not use HAT....
Phytophthora ramorum, an oomycete plant pathogen, is the causal agent of sudden oak death, a serious disease of Fagaceous trees in California and Oregon over the last decade. Tanoak (Notholithocarpus densiflorus) is one of the most susceptible host species, but the cause of host mortality is poorly understood. Previous research...
Prostate cancer is the most commonly diagnosed cancer in men, but rates around the world vary greatly. Americans have the highest incidence rates in the world, 4 to 5 times those of Spain. The hypothesis of this thesis was that vitamin D metabolism is a factor in prostate cancer development...
Numerous populations of salmon and trout undergo extensive migrations, migrating from freshwater to the sea and throughout ocean basins. Years later they return to their natal streams with remarkable accuracy and precision. The outward migration is accomplished without the benefit of following experienced migrants or prior individual experience. Evidence suggests...
Polycyclic aromatic hydrocarbons (PAHs) are significant pollutants in aquatic environments. Many are carcinogenic and lead to DNA fragmentation and adduct formation in marine and freshwater organisms. Previous research demonstrates that rainbow trout (Oncorhynchus mykiss) compensate to long-term PAH dietary exposures and reduce the DNA damage.
The aim of this study...
The goal of this research was to characterize thermal habitat requirements for juvenile redband steelhead trout (Oncorhynchus mykiss gairdneri) in the South Fork John Day River (SFJD), Oregon using physiological indicators of fish condition. Physiological indices of fish condition measured were whole body lipid content and heat shock proteins, specifically...
Perinatal growth restriction programs higher risk for chronic disease during adulthood via morphological and physiological changes in organ systems. Perinatal growth restriction is highly correlated with a decreased nephron number, altered renal function and subsequent hypertension. I hypothesize that such renal maladaptations result in altered pharmacologic patterns for life. Pregnant...
Two studies were conducted to evaluate the influence of supplement composition on intake and digestibility of a low-quality (< 6% CP), cool-season forage, as well as cow performance. Treatments included a non-supplemented control (CON), corn (approximately 8% CP), corn and urea (LU = corn + 0.09 mg/kg BW urea, approximately...
The removal of microbial populations from potable water has been a practice with great importance towards public health, as it has resulted in the reduction of literally millions of cases of infectious disease. In the United States, pathogenic organisms are most commonly removed from drinking water through the application of...
We conducted two experiments evaluating perennial ryegrass straw as a forage source for ruminants. Experiment 1 evaluated digestion and physiological variables in steers offered perennial ryegrass straw containing increasing levels of lolitrem B. Sixteen ruminally cannulated Angus X Hereford steers (231 ± 2 kg BW) were blocked by weight and...
Numerous dietary factors have been shown to influence the fatty acid profiles (FAP)
in breast milk from lactating women. However, few studies have evaluated the effect of trace
minerals on milk FAP. Consequently, the purpose of this study was to determine the effect
of selenium status on the FAP in...
The seasonal distribution of bioavailable organochiorine contaminants in surface
water and the potential environmental factors influencing their bioavailability were
evaluated. The study was carried at the lower Willamette River at Portland Harbor, Oregon
where surface water runoff varied according to season. Bioavailable water concentrations of
DDTs and PCBs were determined...