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Full-Text Articles in Life Sciences

Phenotypic Profiles Of Lymphocytes In Adult C57bl/6n Mice Infected With Cryptosporidium Parvum, Diane Rose Bienek May 1994

Phenotypic Profiles Of Lymphocytes In Adult C57bl/6n Mice Infected With Cryptosporidium Parvum, Diane Rose Bienek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to quantitate the populations o f lymphocytes in the spleens and intestines of normal and immunosuppressed adult C57BL/6N mice that were noninfected or infected with Cryptosporidium parvum. This was accomplished by using the following methodologies: immunohistochemistry, ELISA-spot assay, and flow cytometry.

Mice in groups 1 and 2 were immunosuppressed, but only group 2 was infected. Mice in group 3 were only infected, whereas group 4 served as the normal control. Mice were immunosuppressed with dexamethasone (DEXI at a dosage of 125µg/mouse/day. Infected mice received 106 oocysts per os. The numbers of lymphocytes were …


Fuel Load And Plant Community Dynamics Of Bryce Canyon National Park, Doug W. Wight May 1994

Fuel Load And Plant Community Dynamics Of Bryce Canyon National Park, Doug W. Wight

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A comprehensive fuel load assessment of all plant communities in Bryce Canyon National Park is provided. Fuel loads by community type are pooled into "fuel type associations" based on similarity in predicted fire behavior, and the fuel type associations are mapped throughout the Park. For each fuel type association, a series of fire behavior simulations is presented describing expected rates of spread and intensities for typical conditions in each month of the fire season and for a worst-case scenario. These fire behavior predictions provide guidelines for writing prescribed burning prescriptions or for quickly assessing the need for possible fire suppression …


Modeling Forest Dynamics At The Landscape Scale: Integrating A Computer Simulation Model And Geographic Information System, David W. Betz May 1994

Modeling Forest Dynamics At The Landscape Scale: Integrating A Computer Simulation Model And Geographic Information System, David W. Betz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research demonstrates the ability to integrate a computer simulation model with a geographic information system (GIS) to predict forest community dynamics in both the spatial and temporal dimensions. A landscape scale computer simulation model, LANDSIM, was coupled with the Arc/Info GIS to simulate the interaction of forest fires and forest succession at Bryce Canyon National Park, Utah, and to produce maps of the predicted community types. The sensitivity of the model was tested with respect to the fire return interval, maximum neighbor spread, and the effect of slope upon the spread of simulated fires. The model predicts that each …


Dungpat Microenvironmental Effects On Germination And Establishment Of Crested Wheatgrass, Ghulam Akbar May 1994

Dungpat Microenvironmental Effects On Germination And Establishment Of Crested Wheatgrass, Ghulam Akbar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Complementary greenhouse and field studies investigated the effects of ambient environmental conditions on cattle dungpat moisture, temperature, nutrient concentration, and crust formation dynamics, which in turn influence seed germination and seedling establishment in dungpats. 'Hycrest' crested wheatgrass [Agropyron desertorum (Fisch. ex Link) X A. cristatum (L.) Gaert.] was used as a representative revegetation species.

After collecting feces from Holstein steers that had been fed crested wheatgrass seeds, uniform dungpats were prepared and placed on two soil types (loam and coarse sand) in containers under three watering treatments (field capacity, 1/2 field capacity, and no water) in the greenhouse. Dungpat …


Study Of Circulating Antibodies To Heat-Shock Proteins 60 And 70 In Autistic Subjects, Fang-Yi Chiu May 1994

Study Of Circulating Antibodies To Heat-Shock Proteins 60 And 70 In Autistic Subjects, Fang-Yi Chiu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Autism is a behavioral syndrome characterized by a severe impairment of reciprocal social relations, and of verbal and nonverbal communications. Many different etiologic factors such as viral infection and genetic predisposition have been proposed to explain the development of this disorder. Immune abnormalities, such as a decreased lymphoblastic response to T-cell mitogen, defective antibody responses to rubella vaccine, and decreased numbers of T lymphocytes, also have been identified in a subpopulation of patients with autism, which implies that the development of autism in some cases may be due to autoimmune mechanisms.

Recent evidence suggests that immune response to the heat-shock …


Density And Feeding Habits Of Elk And Deer In Relation To Livestock Disturbance, Kenneth Clegg May 1994

Density And Feeding Habits Of Elk And Deer In Relation To Livestock Disturbance, Kenneth Clegg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Elk (Cervus elaphus) and mule deer (Odocoileus hemionus) density and foraging behavior were monitored in conjunction with disturbance by livestock (cattle and sheep) from 1991 to 1993 at Deseret Land and Livestock property near Woodruff, Utah. Elk and deer densities declined by as much as 92% in response to introduction of livestock, while associated areas where livestock were absent did not show this response. Biting rates and bite sizes were estimated and used to determine instantaneous intake rate. These measures were similar between pastures with cattle present or absent in 1992 but differed in 1993 for …


Effects Of Soluble Calcium-To-Protein Ratio On Age Gelation Of Ultra, Je Hong Ryue May 1994

Effects Of Soluble Calcium-To-Protein Ratio On Age Gelation Of Ultra, Je Hong Ryue

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reverse osmosis (RO) and ultrafiltration (UF) retentates were ultra-high temperature (UHT) processed and compared for storage life at room temperature. Viscosity studies indicated that UHT-treated, RO retentate delayed age gelation longer than UF retentate at the same total solids level (26% TS). When compared at 6.4% protein level (2x RO vs 2.7x UF where x=ratio of the feed volume to concentrate volume), the storage life for both RO and UF retentates was about 6 to 8 months.

Sodium hexametaphosphate (SHMP) and disodium phosphate (DSP) at 1, 3, 5, 10, and 20 mM concentrations were incorporated prior to UHT processing …


Influence Of Ultra-High Temperature Process Parameters On Age Gelation Of Mille Concentrate, Mohamed A. Elhilaly May 1994

Influence Of Ultra-High Temperature Process Parameters On Age Gelation Of Mille Concentrate, Mohamed A. Elhilaly

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to investigate the effect of ultra-high temperature process parameters on age gelation of milk concentrate. Skim milk was concentrated to 2X (volume reduction) using reverse osmosis. The milk concentrate was preheated at 75 or 90°C for 20 or 50 s and UHT-processed at 138 or 145°C for 4 or 16 s. Sterilizing methods used were direct steam injection and indirect plate heat exchanger. The samples were aseptically collected in presterilized plastic containers and stored at 15 or 35°C. At 15°C storage temperature, the steam-injected samples gelled in 5 months when 4 s UHT time …


Nutritional Screening Of Utah Rural And Urban Elderly, Rachel Taylor Rood May 1994

Nutritional Screening Of Utah Rural And Urban Elderly, Rachel Taylor Rood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The population of Americans over age 65 is expected to increase from a reported 12 percent in 1988 to 22 percent by the year 2030. Nutrition screening and intervention can help combat the rising need for health care and other services among the elderly by preventing or delaying disability and dependency.

This study was designed to determine the degree of nutritional risk present within the elderly population in rural and urban areas in the state of Utah by conducting an initial nutrition screening using the Determine Your Nutritional Health checklist developed by the Nutrition Screening Initiative. Congregate meal sites were …


The Effect Of Climate And Spittlebug (Aeneolamia Albofasciata) On Buffelgrass (Cenchrus Ciliaris L.) Productivity In The Sonoran Desert, Martha H. Martin-Rivera May 1994

The Effect Of Climate And Spittlebug (Aeneolamia Albofasciata) On Buffelgrass (Cenchrus Ciliaris L.) Productivity In The Sonoran Desert, Martha H. Martin-Rivera

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I conducted field studies during 1984-1988 to determine how (1) precipitation amount and distribution affect buffelgrass [Cenchrus ciliaris L. (Link) l productivity, (2) summer rainfall amount and distribution and temperature influenced the spittlebug (Aeneolamia albofasciata Lalleman) life cycle, and (3) summer burning affects spittlebug densities and buffelgrass productivity.

Experiment I was conducted from 1985 through 1988. Forage samples collected at 15-day intervals were separated into live, recent-dead standing, old-dead standing, and litter. There was a positive relationship between the summer precipitation and the live biomass. Recent-dead standing and old-dead standing decomposed during the summer, fall, or spring.

Experiment …


Pantothenate-P-Nitroanilide As A Substrate For Pantetheinase Assay, Robert T. Davidson May 1994

Pantothenate-P-Nitroanilide As A Substrate For Pantetheinase Assay, Robert T. Davidson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pantothenate-p-nitroanilide has been synthesized for use as a substrate in a continuous spectrophotometric assay of pantetheinase activity monitoring absorbance at 410 nm. Pantothenate-p-nitroanilide is a crystalline compound with a molecular weight of 338.0 and a melting point of 146-149°C. Use of this substrate in the described assay is suitable for enzyme activity determination in high protein content media such as blood serum. Serum pantetheinase activity was determined for rats of varying pantothenate nutriture. Rats with mildly (but significantly, p < 0.05) lower serum pantothenate levels had significantly higher serum pantetheinase activities than the control group (6.24 nmol/min/ml ± 0.72 and 16. 16 nmol/min/ml ± 4. 14, respectively, p=0.0005).


Microstructural Changes In Casein Micelles During Acidification Of Skim Milk, Hongwen Du May 1994

Microstructural Changes In Casein Micelles During Acidification Of Skim Milk, Hongwen Du

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pasteurized skim milk was acidified using glucono-δ-lactone (GDL) at 10, 20, 30, and 40°C or with 1.2% freeze-dried yogurt starter culture at 40°C. Milk coagulation was followed by measuring turbidity, curd firmness, particle size, and casein micelle microstructural changes using transmission electron microscopy .

The pH of milk was gradually lowered during acidification with GDL or starter culture. Acidification rate showed greater influence on turbidity change at 10°C than at 20, 30, or 40°C.

Average casein micelle size increased with decreasing temperature. The patterns of average micelle size versus pH were not affected by temperature. No great variation of average …


Uptake, Absorption, And Adsorption Kinetics Of Ferrous And Ferric Iron In Iron-Replete And Iron-Deficient Rats, Madhavi Ummadi May 1994

Uptake, Absorption, And Adsorption Kinetics Of Ferrous And Ferric Iron In Iron-Replete And Iron-Deficient Rats, Madhavi Ummadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Various concentrations of ferrous and ferric iron solutions were held at room temperature for 60 min before they were assayed for ferrous iron, which may be unstable due to oxidation. The ferrous and ferric solutions (in pH 2 HCl) were maintained as such for 60 min without the use of chelators. There was no significant oxidation of ferrous iron. Also, four different levels of each ferrous and ferric iron were injected into proximal duodenal loops of rat intestine and uptake was determined at four different time intervals. Two iron-replete rats were assigned to each of the treatments. The in situ …


Fate Of Β-Lactoglobulin, Α-Lactalbumin, And Casein Proteins In Ultrafiltered Concentrated Milk After Ultra-High Temperature Processing, Mark Christopher Alleyne May 1994

Fate Of Β-Lactoglobulin, Α-Lactalbumin, And Casein Proteins In Ultrafiltered Concentrated Milk After Ultra-High Temperature Processing, Mark Christopher Alleyne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The problem of age gelation in ultra-high temperature (UHT) sterilized milk retentate (ultrafiltered 3x concentrated) is investigated in this work. Transmission electron microscopy (TEM), utilizing the microcube encapsulation technique and protocols for immunolocalization of milk proteins, provides insight into the phenomenon of age gelation of UHT-sterilized, ultrafiltered (UF) milk retentate. Primary antibodies (specific for the native as well as the complexed forms of milk proteins) and secondary antibodies (conjugated to gold probes) are used to elucidate the positions of the milk proteins in various samples of milk from the stage of milking through UHT sterilization and storage for 12 months, …


A Response Surface Study Of Extruded Corn Starch/Skim Milk Powder Blends, Sachin Singh May 1994

A Response Surface Study Of Extruded Corn Starch/Skim Milk Powder Blends, Sachin Singh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Skim milk was ultrafiltered to three lactose/protein ratios and spray dried. The skim milk powder was extruded with pearled corn starch at different moisture contents, protein contents, lactose/protein ratios, and feed rates (control variables). Response surface methodology and a central composite in cube experimental design were used. This design required 30 experimental runs with 16 factorial points, 8 axial points, and 6 center points for replication. The physical and functional properties evaluated were expansion ratio, product temperature, bulk density, color, shear stress, viscosity, and water absorption index (response variables). Scanning electron microscopy was done to evaluate the microstructural attributes of …


In Vivo Biopotency Evaluation Of Chromium-Containing Complexes, Jay Rulon Keller May 1994

In Vivo Biopotency Evaluation Of Chromium-Containing Complexes, Jay Rulon Keller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Seven chromium-containing complexes were tested for effects on blood glucose regulation, serum cholesterol levels, serum triglyceride levels, and body composition. The compounds included Cr picolinate, Cr chelidonate, chromate, Cr chelidamate, Cr arginate, nichrome, and Cr chloride.

The study was divided into two major sections, a rat study and a chicken study. In the rat study all seven chromium-containing complexes were tested. They were administered to the rats in four different testing periods at 1 ppm, 5 ppm, and 25 ppm of chromium. Methods of administration varied for each testing period. After the chromium compounds were administered, a glucose tolerance test …


Effects Of Whey Protein Concentrate, Phosphate, And Sodium Hydroxide On Texture And Acceptability Of Turkey And Beef Rolls, Igor V. Moiseev May 1994

Effects Of Whey Protein Concentrate, Phosphate, And Sodium Hydroxide On Texture And Acceptability Of Turkey And Beef Rolls, Igor V. Moiseev

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Processed turkey rolls were prepared with 1 or 3% whey protein concentrates WPC-50 (pH=5.80), WPC-60 (pH=4.53) and WPC-75 (pH=6.85} containing 50, 60 and 75% protein along with controls (phosphate and no phosphate). Control rolls made with 0.5% phosphate had the highest bind strength, and sensory evaluation scores. Only WPC-75 (1%) was acceptable as a binding agent and flavor enhancer. WPC-60 reduced pink discoloration of rolls, but flavor, bind and cohesiveness scores were unacceptably low. WPC-50 was not an effective binding agent. In general, rolls made with 3% WPC had lower scores for intensity of turkey flavor.

Bind strength and sensory …


Consumption Of Iron-Fortified Cheese And Lipid Peroxidation In Females, Gene Joseph Giunti May 1994

Consumption Of Iron-Fortified Cheese And Lipid Peroxidation In Females, Gene Joseph Giunti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dairy products are important sources of calcium and other nutrients but are a poor source of dietary iron. Cheese comprises a substantial portion of dairy food consumption and has been determined an appropriate medium for iron-fortification. However, iron may promote the potentially harmful process in food and biological systems known as lipid peroxidation. Therefore, the safety of consuming iron-fortified cheese was examined.

Commercial-scale batches of Cheddar cheese were iron-fortified to a level of two milligrams of iron per ounce with either ferric chloride, ferric-casein complex, or ferric-whey protein complex. Fifty-four premenopausal females were divided into three treatment groups and supplemented …


Effects Of Nonfat Dry Milk, Whey Protein Concentrate, And Calcium Caseinate On Color And Texture Of Turkey Rolls, Brent Neeley Dobson May 1994

Effects Of Nonfat Dry Milk, Whey Protein Concentrate, And Calcium Caseinate On Color And Texture Of Turkey Rolls, Brent Neeley Dobson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two studies were conducted to evaluate the effects of milk solids on restructured and emulsified turkey rolls. the milk solids used were nonfat dry milk (NFDM), whey protein concentrate (WPC), and calcium caseinate (CC). Turkey rolls consisted of 100% breast meat or 90:10 or 70:30 breast-to-thigh, salt (1%), water (10%), internal or cluster fat (10%), and 3% of various milk solids (WPC, NFDM, CC).

The objectives of these studies were to 1) determine which ratio between light and dark meat is preferred; 2) determine which of milk solids evaluated will permit the highest level of dark meat incorporation into evaluated …


Manufacture Of A Dairy Dessert From Ultra-High Temperature Milk Concentrate, Mark H. Smith May 1994

Manufacture Of A Dairy Dessert From Ultra-High Temperature Milk Concentrate, Mark H. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this project was to initiate development of a nonrefrigerated dairy dessert product. Milk was concentrated by pressure-driven filtration and then sterilized using ultra-high temperature (UHT) processing. Following sterilization, samples were aseptically inoculated with rennet to coagulate the milk, which was then stored at room temperature. These processing steps produced a dairy dessert that did not require refrigeration. I investigated the influence of total solids, milk fat, rennet dosage, storage temperature, and storage time on curd firmness and syneresis. I investigated the effect on curd firmness and syneresis of giving the concentrate a heat treatment prior to UHT …


The Contribution Of Meats To Energy And Essential Nutrient Intakes Of Women In The United States, C. Dian Martin May 1994

The Contribution Of Meats To Energy And Essential Nutrient Intakes Of Women In The United States, C. Dian Martin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study used the 1987-88 USDA Nationwide Food Consumption Survey to investigate the contribution meat products make to intakes of nutrients at risk of inadequate or excessive consumption by women. The study is unique in that meat nutrients were extracted from mixed dishes, providing a more accurate picture of consumption. Cluster analysis was used to classify nonpregnant, nonlactating women 19 years and older based on their consumption patterns of total meat and individual meats (beef, poultry, processed meats, pork and seafoods) as percent of caloric intake.

Total fat and SFA intakes exceeded National Research Council (NRC) goals regardless of meat …


Incorporating Vegetative Diversity Measures In Forest-Level Planning: A Case Study On The Utah State University School Forest, David N. Holland May 1994

Incorporating Vegetative Diversity Measures In Forest-Level Planning: A Case Study On The Utah State University School Forest, David N. Holland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three indices of forest stand structural and compositional diversity were incorporated into a linear programming, timber-harvest scheduling model to examine the tradeoffs between managing stands for timber production and biodiversity objectives. While harvest-level objectives were fairly compatible with the maintenance of biodiversity, present net worth maximization resulted in substantial reductions in all three measures of biodiversity.


Factors Associated With The Highway Mortality Of Mule Deer At Jordanelle Reservoir, Utah, Laura A. Romin May 1994

Factors Associated With The Highway Mortality Of Mule Deer At Jordanelle Reservoir, Utah, Laura A. Romin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Highway mortality of deer (Odocoileus sp.) is a nationwide concern. In 1991, 538,000 deer-vehicle collisions occurred nationwide. Property damage to vehicles, human injuries and fatalities, and potential impacts to local deer populations occur from deer-vehicle collisions. Techniques have been evaluated to reduce highway mortality of deer; however, an effective, cost-efficient solution does not exist for widespread use. If mitigative technologies are to be successful, we need to understand deer behavior and movement patterns associated with highway relationships. Most research about highway deer kills has focused on white-tailed deer (Odocoileus virginianus) in mixed hardwood habitat types. The …


Assessing Mourning Dove Population Declines: Changes In Nesting Dynamics And The Role Of Perch Sites, Paul M. Meyers May 1994

Assessing Mourning Dove Population Declines: Changes In Nesting Dynamics And The Role Of Perch Sites, Paul M. Meyers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I replicated a nesting study carried out 40 years ago in southern Utah to assess reasons for long-term population declines of mourning doves (Zenaida macroura) in the western United States. I compared current nesting patterns to similar data collected in 1952. I saw little difference in nest success and nest predation, but reproductive output and nest density decreased dramatically. The number of young fledged per pair of adults was only 64% of that estimated in 1952. A 1-2 week delay in the nesting season contributed to this decrease, but cannot explain it entirely. Nest density was about 20% …


The Response Of Five Tropical Plant Species To Natural Solar Ultraviolet-B Radiation, Peter S. Searles May 1994

The Response Of Five Tropical Plant Species To Natural Solar Ultraviolet-B Radiation, Peter S. Searles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tropical regions currently receive the highest global levels of solar ultraviolet-B radiation (UV-B, 280-320 nm) even without ozone depletion. Thus, the influence of natural, present-day UV-B irradiance in the tropics was examined for five tropical species, including three native rainforest tree species and two economically important species. Solar UV-B radiation conditions were obtained vi using either a UV-B excluding plastic film or a near-ambient UV-B transmitting film in a small clearing on Barro Colorado Island (BCI), Panama (9 ° N). Significant differences were often exhibited as increased foliar UV-B absorbing compounds, increased leaf mass per area, and reduced leaf blade …


Influences Of Nitrogen Supply And Elevated Co2 On Nitrogen Consumption, Nitrogen Loss, Tissue Nitrogen Concentration, And Yield Of Hydroponic Wheat, Karl B. Ritchie May 1994

Influences Of Nitrogen Supply And Elevated Co2 On Nitrogen Consumption, Nitrogen Loss, Tissue Nitrogen Concentration, And Yield Of Hydroponic Wheat, Karl B. Ritchie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wheat was grown hydroponically for 23 days (early boot stage) in a controlled environment at NO3- concentrations of 100 and 1000 μmol and CO2 levels of 360 and 1200 μmol mo1-1. Nitrogen consumption and transpiration were measured daily. Tissue nitrogen concentration, total biomass, and percent root mass were measured at harvest. Nitrogen recovery and nitrogen use efficiency were calculated. Elevated CO2 increased nitrogen consumption of the 100 μmol NO3- treatment by 13.6% and the 1000 μmol NO3- treatment by 21.3%. These increases were particularly evident during …


Transcervical Versus Laparoscopic Insemination In Nulliparous And Multiparous Ewes After Estradiol Cypionate Treatment, Tami L. Gage May 1994

Transcervical Versus Laparoscopic Insemination In Nulliparous And Multiparous Ewes After Estradiol Cypionate Treatment, Tami L. Gage

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The only practical method for artificially breeding ewes with frozen semen is laparoscopic insemination into the lumen of the uterine horn. Like all surgical procedures, however, laparoscopic artificial inseminatiom has limitations. The procedure requires surgical skill and costly equipment. Repeated passage of the laparoscope through the abdominal wall causes adhesions. Depositing frozen/thawed semen at the os cervix results in low conception rates. The inability to pass an insemination pipette through the cervix has prevented artificial insemination in sheep from becoming a standard breeding method as in the cattle industry. This study compared laparoscopic and transcervical methods of insemination in nulliparous …


Molecular Toxicology Of Pyrrolizidine Alkaloids, Hea-Young Kim May 1994

Molecular Toxicology Of Pyrrolizidine Alkaloids, Hea-Young Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pyrrolizidine alkaloids are cytotoxic, carcinogenic, and anti-carcinogenic in vivo and in vitro, and they produce many hazardous effects in humans and animals. Pyrrolizidine alkaloids (PAs) also cross-link with DNA and/or protein. However, whether such cross-linking is important to the toxic action of PAs is not known. In addition, the exact mechanism underlying these DNA cross-links or cytotoxicity is also not clear.

In three separate studies, I characterized the nature of PA-induced DNA cross-links and the relationships between PA structures and cross-linking potency. In the first study (Chapter II), I found that cross-linking potency of PA congeners coincided with their …