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A Characterization of Liver Glyoxalase I From Normal Mice and Mice Bearing Lymphosarcoma
The purpose of this investigation was (1) to isolate and purify glyoxalase I from the livers of normal DBA/lJ mice and the livers from mice bearing a lymphosarcoma tumor; and (2) to determine, at least with respect to glyoxalase I, if the tumor has an effect on the chemical properties or structure of macromolecules in an organ removed from tumor locale and not histologically affected by its presence.
Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium
Very little work has been done on bacteria capable of significantly inhibiting algal growth. This thesis reports the research on mixed cultures of a high-temperature strain of algae, Chlorella pyrenoidosa TX71105, and an organism isolated from the air and tentatively identified as a variant strain of Bacillus megaterium.
Some Effects of Electrostatic Fields on Brain Activity in Rats
This study concerned the effects of short-term exposures to continuous (10 kv/meter) and pulsed 20 volts at 640 cps/100 msecs) electrostatic fields on the EEG recorded from external electrodes and hypothalamic activity recorded from implanted electrodes in rats. Each experiment lasted at least 90 minutes. The total energies of the waveforms recorded were integrated and printed out for plotting and analysis. Besides the brain activity, the ECG, respiration, and temperature of the animals were also monitored before, during,and after exposure to the electrostatic fields.
Lipids and Phospholipase Activity of Vibrio Cholerae
One purpose of this investigation is to determine the fatty acid and lipid content of typical Vibrio cholerae cells. The comparison of cholera lipid constituents with those of closely-related bacteria might be of taxonomic value. Furthermore, chemical characterization of the cholera vibrio could provide useful criteria for identification of these disease-producing microorganisms.
Influence of Acclimation and Acclimatization to Seasonal Temperatures on Metabolism and Energetics in the Rusty Lizard Sceloporus Olivaceus
Rates and energy equivalents of consumption (C), egestion+ excretion (FU) , assimilation (A), respiration (R) and production (P) were measured in two groups of Sceloporus olivaceus: 1) a laboratory group acclimated at four seasonally encountered temperatures (15, 20, 25 and 30°C) ; and 2) four acclimatization groups collected at different seasons when ambient temperatures corresponded to 15, 20, 25 and 30°C.
The Vertical Stratification of the Macrobenthos in the Brazos River, Texas
Quantification of stream macrobenthos populations has remained a perplexing problem in rivbrine ecology, despite numerous attempts at improvement. This is in part due to well documented variations in chemical and physical parameters locally and geographically, and resultant adapted macrobenthos populations. Southwood (1968) and Hynes (1970a) have reviewed the various sampling techniques developed'for the census of lotic macrobenthos populations. Needham and Usinger (1956), Chutter (1969), and others have pointed out the difficulty in obtaining adequate numbers of samples which will yield population estimates with desired statistical confidence, and still maintain some degree of sampling economy. Needham and Usinger (1956) and Gaufin et al. (1956) mentioned the "patchy" distribution of aquatic insect populations as the primary source of this difficulty. The concept of patchy distribution in insect populations was originally discussed by Andrewartha (1961). Attempts to improve confidence through improved sampling devices and techniques have led to development of numerous types of samplers. Cummins (1962) indicated that there were almost as many samplers as there were researchers.
Ecological Energetics of the Dobson Fly, Corydalus Cornutus
Rates and energies of consumption (C), egestion (F), assimilation (A), respiration (R), growth (Pg), production of exuviae (Pev), and production of egg masses (Pr) and associated efficiencies, and the effects of seasonal temperature, weight and metamorphic stage upon these factors were examined for a typical individual and cohort of Corydalus cornutus (L.) from a stream in North-Central Texas (330 23'N, 97*5'W). Dobson flies are apparently univoltine in the study area, with 11 larval instars. Emergence, oviposition and hatching occur from late May to August. The typical dobson fly hatches in mid-June, grows rapidly until November, and resumes rapid growth in March, reaching full adult size prior to leaving the stream to pupate in early June. Adult females must feed to provide energy to yolk eggs, produce egg-mass coverings and continue somatic maintenance during their week of reproductive endeavors. Metabolic compensation enables larval dobson flies to maintain preferred and fairly constant rates of R during winter (201-451 pl g-1 h~1; 5-15 C) and summer (985-1173 pl g- h1; 20-30 C); with a seasonal acclimatization change point between 15-20 C. Reduction of rates of R through undercompensation during the winter when food is scarce and through partial compensation at high temperatures during the summer conserves energy which is allocated to P, resulting in high ratios of P/R (1.94) and P/A (66%) for the individual larva and, to a lesser degree, for the cohort (P/R = 1.07, P/A = 52.3%, P/B = 9.96). Rates of C, F, A and R, but not assimilation efficiency, were influenced by temperature and size. The energy budget for a typical dobson fly during the 47 wk as a larva was: C = 4167, A = 3442, F = 725, Pg = 2075, Pev = 198, and R = 1169. Ova respired 0.107 cal wk-1, prepupae 357 cal …
Effects of Shoot X-Irradiation on Water Uptake by Single Isolated Roots of Intact Onion Plants
Using a micro-potometric method, it was ,found that X-irradiation (400 R - 18 Kr) of the shoots of the onion plant Allium cepa will produce an immediate, pronounced (200%) and reversible enhancement of the water uptake by the shielded roots. Unfiltered X-irradiation.(1200 R/min., 120 KVP, 5 ma) was delivered at right angles to the shoot. Readings were taken at 10-minute intervals before, and immediately following X-irradiation. The greatest enhancement occurred at dosages between 4.8 Kr (150%) and 6.0 Kr (190%). The data indicate that the irradiation effect on water uptake was a physical rather than a metabolic one.
Primary Productivity and Community Metabolism in a Small North Central Texas Pond Ecosystem
Rates of primary production and community metabolism were monitored over a one year period using the diurnal oxygen method. Certain physico-chemical parameters were also measured, and autotrophic standing crops were estimated. An in-depth study was made of the phytoplankton community and various diversity indicies were calculated. Simple correlations were run between all parameters measured (biotic and abiotic), and their inter-relationships examined. Multiple linear regression analyses were used to develop equations predictive of production and community metabolism. Bluegreen algae were the dominant phytoplankters with blooms occurring in late summer and fall. Yearly mean production was approximately 21 kcal per meter square per day with a mean photosynthetic efficiency of 1.2 per cent. Of the various parameters measured turbidity and water temperature were most important in determining rates of primary production.
The Effect of Ethanol on Cardiac Activity and Brain Respiration in Chick Embryos
This study concerned the effect of ethanol on cardiac activity and brain respiration in chick embryos. Ethanol dosages tested ranged from 1.0 mg to 4.0 mg/g weight. Each experiment lasted at least 150 minutes. Cardiac activity in terms of total waveform energies was integrated and printed out for plotting and analysis. The embryonic heart rates were simultaneously determined from physical graph tracings. The embryonic brain respiration was measured using a differential microrespirometer. The effect of ethanol on cardiac activity was one of slight (10 to 13), but statistically significant (p<.05) rate depression. The brain slices exhibited a marked, immediate, and irreversible decrease (39 to 89%) in oxygen consumption at both ethanol dosages. The data indicated that chick embryonic brain tissues were more susceptible to alcohol effects than cardiac tissue. Therefore, the mental abnormalities seen in the offspring of alcoholic mothers may be more cerebral in nature than cardiovascular.
The Effects of Diphenylhydantoin on the Lymphoreticular Tissues of the Rat
A study was made of the effects of diphenylhydantoin (DPH) and the carrier solution on the spleen, lymph node, and thymus. DPH was injected i.p. at concentrations of 5 and 10 mg./100 gm. for 30 and 60 days. Hematologic effects observed were leucocytosis, neutrophilia, eosinophilia, and lymphopenia. Respiratory measurements of lymph node tissue slices were made using the oxygen electrode method. The carrier solution was found to cause a marked increase in oxygen consumption. A DPH effect on lymph tissue respiration was not observed. The carrier alone caused an atrophy of the lymph nodes and thymus, as well as an increase in the total body weight. Histological examination revealed that the 5 mg./100 gm. DPH injected for 60 days and the 10 mg./100 gm. DPH injected for 30 or 60 days produced a histiocytic cell type lymphoma, resembling Hodgkin's disease in the lymph node, thymus, and spleen in rats. The data indicated that DPH may not be a direct carcinogen, but it may interfere with the normal immune mechanism to produce the changes observed.
Aspects of the Thermal Ecology of Largemouth Bass (Micropterus salmoides) in North Central Texas
The coefficient of body temperature change (K) ranged from -0.53 to -0.072 for bass weighing 73-1440 g. The double log regression of K on weight was similar to that reported for other poikilotherms (slope = -0.57; R = 0.93). Fingerling bass were eurythermal, being capable of surviving instantaneous temperature changes over a 20 C range at acclimation temperatures of 15, 25 and 30 C and over a 15 C range at acclimation temperatures of 20 and 35 C. Preferred temperatures for adult bass measured in the laboratory ranged from 27-32 C with no relationship to day or night. The overall mean preferred temperature was 29 C. The laboratory determined preferred temperatures were supported by limited field determined body temperatures taken in a vertical temperature gradient near the discharge of a power plant effluent. Routine metabolic rates of bass from a heated reservoir and a nearby hatchery were similar from 10-30 C in summer and winter. The weight exponent (0.77) and Q^gS (1*6-2.9) were similar to those published for more northern bass populations; however, the Texas bass had lower metabolic rates than those published for the northern populations. Bass exposed to rapid temperature increase (0.2 C/min) from 25-30 C increased their metabolic rate by 53% but showed no detectable increase in opercular rate. Bass warmed from 30-35 C and 30-33 C increased their metabolic rate by 140%, and their opercular rates increased to over 100 beats per minute before death.
Serological Relationships of Azotobacter Species
In order to clarify the taxonomic problems which exist among the group azotobacter by serological method, 24 cultures of Azotobacter including 9 species were tested as antigens in Ouchterlony plates against 3 different antisera obtained from rabbits immunized with A. chroococcum ACl6, A. macrocytogenes St.M. and A. vinelandii 12837, respectively. The results showed more cross reactivity in intraspecies reactions than in interspecies ones and indicated the presence of a common immunogenic determinant. This work presents the results which suggest the effecient classification of Azotobacter by Ouchterlony comparisons of corresponding antigens in different species.
Limitation of Primary Productivity in a Southwestern Reservoir Due to Thermal Pollution
Evidence is presented to support the conclusions that (1) North Lake reservoir is less productive, contains lower standing crops of phytoplankton and total organic carbon than other local reservoirs; (2) that neither the phytoplankton nor their instantaneously-determined primary productivity was detrimentally affected by the power plant entrainment and (3) that the effect of the power plant is to cause nutrient limitation of the phytoplankton primary productivity by long-term, subtle, thermally-linked nutrient precipitation activities.
The Relation Between Carbon Assimilation and Biomass Dynamics in a Phytoplankton Community
Production dynamics in the phytoplankton community of a mesotrophic Texas reservoir were measured weekly over a four month period using 14C incubation and ATP assay methodologies. Assimilation values of 14C ranged from 0.2 to 45 ug C 1 hr1 - . Significant positive and occasionally negative changes in biomass (i.e. viable organic carbon) were observed in short term (4 hr) in situ incubations juxtapo-sitioned with the 14C experiments; viable organic carbon production, estimated with the ATP assay, ranged from -25 to +50 ug C 1l1hr1. Carbon assimilation and biomass changes did not correlate in either short term (4-5 hr.) or over the study period (6 months). However, weekly biomass trends were predicted by relative positive or negative biomass changes in the short term incubations. Biomass measurements gave a more sensitive insight into production dynamics in the phytoplankton community than did carbon assimilation measurements.
Dielectric Properties of Azotobacter vinelandii in a Microwave Field
A resonant frequency cavity was used to determine the dielectric properties of various preparations of Azotobacter vinelandii ATTC 12837. It was found that the bacteria investigated did interact with microwave radiation in the absence of free water. The data presented here indicate that bacteria demonstrate frequency specific dielectric properties. The techniques employed in these experiments may also be used to determine microwave spectra of other species of bacteria in different physiological stages.
The Life History of the Mayfly Isonychia sicca (Walsh) (Ephemeroptera--Siphlonuridae) in an Intermittent Stream in North Central Texas
The life history of Isonychia sicca (Walsh) was elucidated from samples collected at Clear Creek from Oct. 1976-Jun. 1978, and Elm Fork of the Trinity River from Sept. 1977-Jun. 1978, Denton County, Texas. Adaptations for existence in an intermittent stream were of primary concern. Eggs are capable of diapausing through hot, dry summers and cold, wet or dry winters. Diapause is broken in the fall after rehydration and/or in the spring. I. sicca is usually bivoltine during a Sept.-Jul. wet period. Observations from Elm Fork indicate that emergence continues to Oct. if the stream remains permanent. Considerable overlap occurs between overwintering, spring, and summer populations.
Size Fractionation of Metabolically Active Phytoplankton and Bacteria in Two Diverse Lentic Systems
Simultaneous size fractionation of plankton populations associated with NaH^14CO_3 and ^3H-glucose uptake was employed in eutrophic Lake Texoma (Texas and Oklahoma) and oligotrophic Flathead Lake (Montana). Autoradiography was utilized to determine the role of specific microorganisms in community metabolism. Ultraplankton (0.45-10 μm) dominated plankton numbers and metabolic activity in both aquatic systems. Many of the most abundant species were not the most productive, in terms of inorganic C fixation. Rates of heterotrophic uptake of ^3H-glucose were small in comparison to photolithotrophic uptake in both lakes, Photoheterotrophy was more extensive in Flathead Lake, Autoradiographs indicated that bacteria were responsible for observed photoheterotrophy. Oscillatoria sp. exhibited. mixotrophy in Lake Texoma,
Population Dynamics of Macrobenthos in a Regulated Stream 1970-71 and 1978
Stability of the macrobenthic community in a regulated section of the Brazos River, Texas, was evaluated. Physicochemical data and information on spatial distribution of macrobenthos were collected. Populations of two invertebrate species, Isonychia sicca and Neoperla clymene, had been greatly reduced since 1970-71 and I. sicca had been practically eliminated from this section of the Brazos. Three other insect populations, Choroterpes mexicanus, Cheumatopsche campyla and Cheumatopsyche lasia, had more than doubled their numbers since the 1970-71 study. A physicochemical gradient existed in this regulated section of the Brazos but it appeared to have changed little in comparison of earlier chemical data. A gradation of the macrobenthic community was evident as distance from the dam increased,
Chemically Active Odorants as Olfactory Probes
The initial step in odor recognition by the nose is the binding of odorant molecules to receptor sites embedded in the dendritic membranes of olfactory receptor cells. Despite considerable interest and experimentation into the nature of these receptor sites, little is known of their specificity to different types of odorant molecules. This lack of knowledge partially stems from the fact that the nature of receptor proteins is most effectively studied when specific and irreversible inhibitors are available for use as chemical probes, yet no such agents have been discovered for use in the olfactory system. A series of alkylating agents and other chemically active odorants were tested to determine whether they might react with specific odorant receptors and modify olfactory responses. Electroolfactogram (EOG) recordings were obtained before, during, and after treatment of the olfactory mucosae of grass frogs (Rana pipiens) with a chemically active odorant.
Effects of Aging on ACTH-Stimulated Steroidogenesis in Subcellular Fractions from Rat Adrenal Glands
Young, middle-aged and old rat adrenal gland steroidogenesis was measured in isolated, superfused glands and in their subcellular fractions before and after adrenocorticotropic hormone treatment. In the latter experiment, five corticosteroids were extracted from six different subcellular fractions. Superfused glands initially produced relatively high glucocorticoid levels; thereafter, production decayed asymptotically. Steroidogenesis by young and middle-aged glands was maintained at least 1.5 to 2.5 hours before it decayed; old glands were 50% less active than younger ones and production decayed within one hour. High cholesterol and progesterone levels in certain old gland fractions were associated with correspondingly reduced 11-deoxycorticosterone and corticosterone. It is suggested that synthesis of these glucocorticoids from their accumulating precursors weakens with age.
Effects of Pulp and Paper Mill Effluent on Stream Primary Productivity in the Lower Sulphur River, Texas
Responses of periphyton and phytoplankton productivity in the lower Sulphur River (Texas-Arkansas) to bleach-kraft mill effluent (BKME) were monitored using in situ ¹⁴C incubation. Carbon assimilation rates measured downstream of mill discharge were substantially reduced from upstream levels. Periphyton and phytoplankton chlorophyll a concentrations remained relatively unchanged by the presence of BKME. Periphyton ash-free dry weight increased near the mill outfall, but decreased further downstream. Calculated productivity efficiencies (productivity:biomass) varied with variations in ¹⁴C rates. A laboratory bioassay was designed to determine the effect of BKME light-attenuation on photosynthetic rates of upstream Sulphur River periphyton and Selenastrum capricornutum Prinz. Pooled results of bioassay runs indicated a 20 per cent BKME concentration effectively reduced control ¹⁴C-assimilation levels by 50 per cent. The downstream reduction observed for in situ productivity was 5 per cent lower than that predicted by the color bioassay.
Comparative Feeding Ecology of Leaf Pack-Inhabiting Systellognathan Stoneflies (Plecoptera) in the Upper Little Missouri River, Arkansas
The feeding ecologies of leaf pack-associated systellognathan stoneflies were examined from 6 June 1980 21 May 1981. Species composition, seasonal abundance, nymphal growth, feeding habits and mouthpart morphology were determined for the eight dominant stonefly species. Prey preferences and predator-prey size relationships were also examined for omnivorous and carnivorous species. Foregut analysis from 2860 individuals indicated opportunistic feeding on the most abundant prey insects, usually in proportion to prey frequency. Feeding preference studies generally indicated random feeding on major prey groups. Prey and predator sizes were usually highly correlated (p<0.01), with predators expanding their prey size thresholds with growth. The potential for competition between sympatric stoneflies for prey is discussed.
Comparative Ecology of Benthic Communities in Natural and Regulated Areas of the Flathead and Kootenai Rivers, Montana
A comparative study was made of environmental variables and the density, biomass, diversity, and species composition of macroinvertebrates in areas downstream from a dam with a hypolimnetic release (Hungry Horse Dam on the Flathead River) and a dam with a selective withdrawal system (Libby Dam on the Kootenai River). A major objective of this study was to examine the response of macroinvertebrate communities to defined environmental gradients in temperature, flow, substrate, and food-related variables (periphyton, particulate organic carbon in the seston). In addition, the effects of experimental manipulations in discharge on macroinvertebrate drift and stranding were assessed, and the effects of temperature on the growth rates and emergence of five species of insects were measured.
Genetic and Morphological Variation in Natural Populations of the Red Shiner, Notropis lutrensis, and their Relationship to Adaptation in a Generalist Species
Twenty-two natural populations of the red shiner minnow, Notropis lutrensis were examined for morphological and genetic variation. This research was aimed at testing the hypothesis that morphological and genetic variation was primarily influenced by the degree of gene flow between populations. Ten linear measurements were taken from each of 1320 specimens. Morphological characters were adjusted for differential growth by least squares linear regression techniques. Genetic variability was estimated for each individual red shiner through the methods of starch gel electrophoresis. Twenty presumtive gene loci were resolved.
Emergence, Growth, Drift and Microdistribution of Stoneflies (Plecoptera) in an Ozark Foothills Stream, Delaware County
Adult stonefly emergence, nymphal growth, drift and microdistribution were examined in Battle Branch, a secondorder, spring-fed stream, from November, 1982 to May, 1984. Adults of 22 species emerged successionally, with specific adults present every month. Searching emergent objects and the stream margin was best for collection of winter and early spring emerging species. Sweeping the streamside and light trapping were most efficient for late spring and summer emerging species. Nymphal growth for nine abundant species generally fit double log or semilog models. Drift was low, but did show a post-sunset pulse. Generally, leaf material was found to be significantly related (p<O.001) to density, diversity and biomass of stoneflies in Battle Branch.
Food Habits, Dietary Overlap and Electivity of Non-Game Insectivorous Fishes in an Ozark Foothills Stream
Etheostoma spectabile, E. punctulatum, and Cottus carolinae were sampled Mar., 1983, - Feb., 1984, in Flint Creek, Oklahoma. Immature E. spectabile ate primarily microcrustaceans, while mature fishes relied more on mayflies and amphipods. Juvenile E. punctulatum fed upon mayflies, amphipods, and Asellus. Mature E. punctulatum ate primarily mayflies, and other relatively larger prey. Cottus carolinae consumed chironomids almost exclusively in Jan. - Feb., 1984, while mayflies were predominant the remainder of the year. No significant habitat partitioning between the two darters, and seasonal habitat segregation between C. carolinae and the two darters was found. Dietary overlap between the darters was significantly correlated (p<0.0005) to differences in x prey sizes.
Effect of Calcium Channel Antagonists and Other Agents on Olfactory Reception
The role of Ca++ in olfactory responses was investigated with inorganic and organic calcium channel antagonists. Electrophysiological responses to odorants were recorded from frog olfactory mucosa before and after aerosol application of different agents. Electroolfactogram responses were blocked by certain inorganic ions with the order of effectiveness Zn++ >Ln+++>Cd++>Ca++>Co++>Sr++>Mg++. Ba++ potentiated olfactory responses, and is known to potentiate calcium channel-mediated responses in other tissues. Certain local anesthetics which are thought to act through calcium channel blockade were inhibitory to olfactory responses, with the order of effectiveness being dibucaine>tetracaine>procaine. These data support the idea that Ca++ is involved in olfaction, perhaps acting as a current carrier and/or a second messenger. Preliminary experiments on channel localization were performed using a silicon-labeled amine. Attempts to localize the silicon label were inconclusive, although silicon was detected in the olfactory tissue.
Effects of Water Source, Suspended Solids, and Acclimation on Biotransformation of 2 /4-Dichlorophenoxy Acetic Acid in Aquatic Systems
In recent years there has been a great deal of scientific interest in processes that affect the fate of organic chemicals in the environment. one main reason for this increased interest is due to greater environmental concern over accidental or purposeful release of these chemicals into the environment by man. A major environmental concern is the increased use of pesticides over the last few years. In the thirty years prior to 1978 the use of pesticides has increased by a factor of forty (Ridgeway et al., 1978). Recently the use of herbicides has been increasing, but that of insecticides has stabilized (Willis, 1983). Detectable amounts of organic pesticides can be found in many areas of the biosphere. For toxic organic chemicals to be used safely, researchers must have a clear understanding of the fate and persistence of these chemicals when they are released into the environment. This understanding will also allow the development of new products that, when properly used, will not produce adverse effects to man or the environment (Weber, 1972). According to the Toxic Substance Control Act (TSCA) any new or expanded-use chemical that might be released into the environment must be tested for environmental hazard.
Neuroregulation and Myosin Light Chain Phosphorylation in Ascaris Suum Obliquely Striated Skeletal Muscle
Extraction and quantitation of myosin light chain two coupled with myograph recordings from Ascaris muscle perfused with calmodulin inhibitors and neurotransmitters in conjunction with their respective agonists and antagonists have been used to establish the regulation of contraction in this muscle. Densitometric tracings of isolectric focusing gels separating the regulatory light chain were used to quantitate phosphorylation in resting, contracted and flaccid muscle. These studies indicated that inhibitory neurostimulation is mediated by a true GABA receptor. Myosin-mediated contraction is responsible for maintaining the level of tension observed in resting actin-mediated muscle. Actin-mediated contraction is responsible for the rapid rise in tension following excitatory stimuli. Both systems function simultaneously and are independant.
The Eosinophil and Lysophospholipase Responses in Mice Infected with Trichinella spiralis: A Role for the Lymphocyte and Macrophage
The relationship among eosinophils, lysophospholipase activity and the immune response in animals infected with Trichinella spiralis was studied using in vivo and in vitro techniques. In an in vivo experiment, anti-thymocyte serum (ATS) was administered to mice infected with T. spiralis and its effects on intestinal lysophospholipase (EC 3.1.1.5.) activity, peripheral blood, bone marrow and intestinal eosinophilia were measured in the same experimental animal. The ATS caused a significant temporally related suppression of both the tissue lysophospholipase response and eosinophilia, in all three compartments. These findings support the hypothesis that parasite-induced eosinophilia is the cause of the increased lysophospholipase activity of parasitized tissue and that the responses are thymus cell-dependent. In vitro experiments demonstrated that the eosinophil was the primary inflammatory cell source of lysophospholipase among eosinophils, neutrophils macrophages and lymphocytes. The role of other cells and antigen in the production of the enzyme by the eosinophil was also investigated in vitro• Results demonstrated that eosinophils cultured with both T. spiralis antigen and other leukocytes yielded enzyme activities significantly greater than eosinophils cultured alone or with only antigen. More specific experiments showed that T-lymphocytes were the cells responsible for influencing the eosinophils' lysophospholipase activity in the presence of antigen, and that their influence was enhanced by the presence of macrophages. These results suggested that increased lysophospholipase activity present in parasitized tissue was not only due to increased numbers of eosinophils infiltrating parasitized tissue but was also due to each eosinophil synthesizing more of the enzyme. The necessity for antigen and other cells suggests a role for cell cooperation in the production of the enzyme, specifically T-lymphocytes and macrophage interaction with the eosinophil. A lymphocyte soluble factor collected from sensitized lymphocytes stimulated with specific antigen or concanavalin A was found to enhance the eosinophil lysophospholipase activity when added to cultures of …
The Genetics of Pigmentation in Corynebacterium poinsettiae ATCC 9682
Corynebacterium poinsettiae mutant strains blocked in carotenoid biosynthesis were obtained by treatment with the mutagen N-methyl-N1-nitro-N-nitrosoguanidine. Additional carotenoid (Crt) mutant strains were obtained from a previous study conducted in our laboratory. Fifty-nine Crt mutants affected in carotenoid biosynthesis were examined by a normal phase high performance liquid chromatography (HPLC) system. Pigment extracts of Crt mutants and C. poinsettiae wild type strains were resolved by an isocratic system with hexane:acetone:dicholoromethane, 11.35:1.73:1.00 (by vol.) as the eluting solvent. In addition to the five major peaks, twelve minor peaks were observed in the wild type C. poinsettiae strain used in this study. Crt mutant and wild type strain peak heights were measured from the individual chromatograms and the peak height data set created was analyzed using the Statistical Analysis System program to perform a cluster analysis. The cluster analysis revealed five carotenoid mutant groups. Carotenoid pigments which accumulated or were absent in each of the cluster groups are reported. Cluster group 1 mutants (CrtA) are blocked in the dehydrogenase(s) which is(are) responsible for the dehydrogenations between phytoene and lycopene. Cluster group 2 mutants (CrtB) appear to be blocked at a second dehydrogenase specific for the dehydrogenation from C.p. 470 to C.p. 496. Cluster group 3 mutants (CrtC) are blocked at a cyclization step in the pathway which involves cyclization of C.p. 496 to C.p. 470 and which may cyclize C.p. 473 to C.p. 450. The genes CrtA and CrtB map only 0.5 map units from each other while CrtA and CrtC map 2.1 map units from one another. Mutants which accumulate end products but which lack certain precursors indicate a branched pathway for pigment biosynthesis exists in this organism. Media for the formation, fusion and regeneration of C. poinsettiae protoplasts are reported and a protocol for the use of these media in genetic …
Radial Compression High Performance Liquid Chromatography as a Tool for The Measurement of Endogenous Nucleotides in Bacteria
High performance liquid chromatography was used to measure ribonucleoside triphosphates in microbial samples. Anion exchange columns in a radial compression module were used to separate and quantify purine and pyrimidine ribonucleotides. Endogenous ribonucleoside triphosphates were extracted from Escherichia coli and pseudomonas aeruginosa using three different solvents, namely trifluorocetic acid (TFA; 0.5M), trichloroacetic acid (TCA; 6 per cent w/v) and formic acid (1.0M) Extracts were assayed for uridine 5'-triphosphate (ATP), and guanosine 5'-triphosphate (GTP) by using anion exchange radial compression high performance (pressure) liquid chromatography. The three extraction produres were compared for yield of triphosphates. E. coli, the TFA extraction procedure was more sensitive and reliable than TCA and formic acid extraction procedures, but , in P. aeruginosa, the best yields of ATP and GTP were obrained following extraction with TFA. Yields of UTP and CTP increased when extraction was performed in TCA. These data illustrate that different extraction produres produce different measures for different triphosphates, a point often overlooked.
An Analysis of Respiratory Mechanisms Controlling Exercise Hyperpnea During Cycle Ergometry Conducted at Selected Workloads and Pedal Frequencies
Respiratory and metabolic patterns in response to variations in exercise workload (WL) and pedal frequency (RPM) were examined in 10 healthy males. Each subject performed WLs of low (L), moderate (M) and high (H) intensity, equivalent to 25%, 50% and 75% V02 m a x at 7 pedal frequencies (40, 50, 60, 70, 80, 90 and 100 RPM). ANOVA ( 3 X 7 design) indicated that WL and RPM had independent and significant effects on all respiratory and metabolic measures; i.e., the greater the WL and RPM, the higher the HR, V02, VC02, Ve, Fb, Vt, Vt/Ti, Vt/Te and Ti/TtQt and the lower the Ti and Te. However, analysis of the interaction effect revealed different response patterns for Fb, Vt, Ti, Vt/Ti, Vt/Te and Ve among the WLs. During L-WL, increases in RPM produced increases in Ve which were due to progressive increases in both Fb and Vt. However, during M-WL and H-WL, increases in RPM produced increases in Ve which were accomplished by a constant Vt and a progressive increase in Fb. My findings suggest that during low WLs, the signal for Vt is dependent on rate of contraction, while during M-WL and H-WL, the signal for Vt appears to depend on force of contraction and is independent of increasing RPM. When comparing the L-WL and M-WL, alterations in Ve, Fb, Vt/Ti and Vt/Te in relation to increases in pedal frequency were additive. However, when these two lower WLs were compared to the H-WL, the interaction between pedal frequency and Ve, Fb, Vt/Ti and Vt/Te was multiplicative. In addition, the interaction between WL and RPM on Vt and Ti was additive when comparing the M-WL and H-WL and multiplicative when these two lower WLs were compared to the H-WL. Correlation analysis indicated that for all WLs, Te was more …
Roles of Calcium Ions and Cyclic AMP in Olfactory Transduction
The roles of Ca2 + and cAMP in olfactory transduction were explored using agents which affect calcium channels and second messenger systems. These agents were applied at certain calculated final concentrations onto olfactory epithelia of urethane-anesthetized frogs (Sana PiPlens) by two-sec aerosol spray. During extracellular recording, saturated vapors of isoamyl acetate were delivered every 100 sec in 0.3 sec pulses to produce an electroolfactogram (EOG). Inorganic cations that block inward calcium currents inhibit EOG responses with the following rank order: (La3+) > (Zn2+, Cd2+) > (Al3+, Ca2+, Sr2+) > (Co2+). Application of 7.5 mM La3+ eradicates £0G's, while Ba2+ (which can carry more current that Ca2+) initially produces significant enhancement (F=43.04, p<0.001, df=19). Magnesium ion has no effect on EOG's at 7.5 mM, while 1.5 X 10"4M Ca2+ is significantly inhibitory (F=5.74; p=0.0355; df=12). Control aerosol sprays of distilled water depress EOG's by an average of 5%. The organic calcium channel antagonists diltiazem and verapamil inhibit EOG's by 17% and 36X, respectively, at a concentration of 1.5 X 10~*M. Verapamil produces significant inhibition (F=17.17; p=0.002; df=ll) at 1.5 X 10" 5 M, while the 1,4-dihydropyridine calcium channel antagonists, nicardipine and nifedipine, do not inhibit beyond 1% DMSO controls. Several calmodulin antagonists decrease EOG's, but without correlation to their anti-calmodulin potency. Application of 1.5 X 10"*M chlorpromazine and N-(6-aminohexyl)-5-chloro-l-naphthalenesulfonamide inhibit EOG's by 31% and 27%, respectively, while trifluoperazine inhibits by 23%. Dibutyryl cAMP, a lipophilic mimic of cAMP, produces 54% inhibition at 1.5 X 10" *M. Dibutyryl cGMP, cGMP, cAMP, and adenosine all decrease EOG's by less than 15% compared to distilled water controls. Forskolin, a reversible activator of adenylate cyclase, inhibits EOG's by 57% at 1.5 X 10"5M, which is significant beyond the 1% DMSO controls (F=17.17; p=0.002; df=ll). These data support the hypothesis that Ca2+ participates in olfactory transduction. …
Resistance and Morphology of Azotobacter Vinelandii Grown on Dialyzed Soil Agar
The objectives of this research were to identify the form of Azotobacter as it exists in situ in the soil; to compare its resistance to that of laboratory grown cysts typical of those described in the literature; and to compare its resistance to that of cells grown on dialyzed soil agar. In addition, the morphology of the cells grown on dialyzed soil agar was examined by light and electron microscopy and then compared to the cysts grown on n-butanol Burk's medium. Dipicolinic acid and oxygen uptake rate were measured in cysts and on cells grown on dialyzed soil agar in order to determine whether the cells grown on dialyzed soil agar were endospores or other dormant form and also to measure the respiratory quotient in these cells.
Boron Deficiency and its Associated Perturbation of Nucleotide Metabolism in Tomato Plants
The effect of boron deficiency was studied in tomato plants grown hydroponically. Morphological studies showed that boron deficiency in the root system caused a cessation of root elongation, browning and thickening of root tips, the formation of branch roots close to the apex and decrease in the overall size of the root. The pyrimidine biosynthetic pathway remained intact and functional under boron limitation. The sugar nucleotide, uridine diphosphate glucose, was diminished in boron deficient medium and its level was restored to that of born sufficiency when uracil, cytosine, uridine, cytidine or orotic acid was provided.
Interaction of Microwaves and Germinating Seeds
This investigation was concerned with determining the interaction of microwaves with germinating seeds. This study covers two different approaches. The preliminary efforts covered the response of germinating seeds to treatment by microwaves and heat. The second phase of the investigation used microwaves as a probe to determine some of the processes of early seed germination. The preliminary investigation measured the internal metabolic process by ATP production. Leakage of ions and organic material from germinating seeds indicated that membranes are a target of microwaves and heat. Electron photo-micrographs showed an increase in damage to membranes as heat and microwave treatments were increased. The second phase of this investigation was concerned with determining some of the biological activity at the initiation of germination of wheat seeds, Triticum aestivum L., using a resonating microwave cavity oscillating at 9.3 GHz as a probe. Direct current conductivity measurements were also made on the seeds as a means of confirming the observations made with the microwave cavity. There was no observable difference between treatment by UHF or heat in the ultrastructure of germinating seeds. A dielectric response far above that of free water was found as live seeds of wheat began to imbibe water. This effect was assumed to be due to the release of ions, because conductivity increased as corresponding quantities of water were imbibed; and both conductivity and dielectric response decreased as imbibition progressed. Although dead seeds also imbibe water, they do not show this decrease in dielectric response. The dielectric response of live seeds was reduced after the initial imbibition, showing that water became tightly bound as imbibition progressed. The dielectric response of actively growing shoots from the seeds was much less than that of the seeds themselves. The large quantity of water in the shoots is assumed to be immobile, being tightly …
De Novo Glycogen Biosynthesis by a Glycogen Primer Complex in the Obliquely Striated Skeletal Muscle of Ascaris suum
During the purification of the enzyme glycogen synthase from the muscle of the nematode Ascaris suum, approximately 70% of the glycogen synthase activity can be separated from the bulk of cellular glycogen by centrifugation for 60 min at 105,000 x . The glycogen synthase in the supernatant fraction has an Mr of 1.2 x 106 as determined by Sepharose 4B gel filtration chromatography. The glycogen synthase in this high molecular weight complex (glycogen primer complex) can be further purified by ConA-Sepharose affinity chromatography; the enzyme activity was eluted with 100 .mM a-methylmannoside. The glycogen synthase in glycogen'primer complex is predominately in the glucose 6-phosphatedependent form. The glycogen primer complex can catalyze the transfer of glucosyl units from UDP-glucose to an endogenous acceptor in the absence of exogenous glycogen. Analysis by SDS-PAGE showed three proteins (Mr 140,000, 78,000 and 34,000) and a carbohydrate polymer. The carbohydrate polymer can be partially digested with a-amylase. The glycogen primer complex was further digested by acid hydrolysis, and upon descending paper chromatography analysis, eight different carbohydrates were isolated, two of which were tentatively identified as glucose and sialic acid. The [14 C]-autoradiograph showed that in vitro synthesis of a glycogen-like polysaccharide occurred on this carbohydrate polymer. Polyclonal antibodies have been made to the glycogen primer complex, and Western Blot analysis indicated that all three proteins of the glycogen primer complex were antigenic. Collectively, the data indicate that a glycogen-like polysaccharide is synthesized from a carbohydrate-associated protein primer in the muscle of this worm.
Aspects of Fathead Minnow Reproductive Behavior
Following a study of normal reproductive behavior of fathead minnows, Pimephales promelas, experiments were conducted to determine the stability/variability of behavior by sexually mature, territorial males under a variety of manipulated conditions. Collectively, these experiments indicate that although the individual behaviors of fathead minnows appear to be quite variable, the overall process, reproductive behavior, is stable.
Pre-Impoundment Estimations of Nutrient Loading to Ray Roberts Lake and Prediction of Post-Inundation Trophic Status
Excessive nutrient loading of natural and artificial lakes has led, in some systems, to plethoric algal and aquatic macrophyte growth which can result in aesthetic degradation and undesirable tastes and odors. It would be advantageous to have some indication of the potential trophic status of a reservoir before it is filled. An objective of this study was to assess the water quality and nutrient loading potential of the tributaries entering Ray Roberts Lake, a large reservoir located in north central Texas. Samples from a maximum of thirteen sites were collected on the Elm Fork, Trinity River, Isle duBois Creek, and five additional tributaries. Data were also collected during six storms, from atmospheric deposition collectors, and from soil-water microcosms. The relationship between watershed landuse and mean water nutrient concentrations was evaluated. Significant differences will exist between the two major arms of Ray Roberts Lake: Elm Fork, Trinity River and Isle duBois Creek. While the majority of the annual phosphorus and nitrogen load entering both tributaries is coming from overland flow, the proportion is higher in Isle duBois Creek. Point sources in the Elm Fork contribute a larger percentage of the bioavailable phosphorus, which is significantly greater than in Isle duBois Creek. The water quality of Isle duBois Creek, especially nitrogen, is affected to a greater degree by the landuses in its watershed. Predictive regression models made accurate estimations of stream nutrient concentrations in Isle duBois Creek. The entire reservoir, upon reaching equilibrium conditions, will be classified as a eutrophic lake. The Trinity arm, with a higher phosphorus load, will display a higher trophic status. The Isle duBois arm has a lower phosphorus load which will give it a lower trophic status. The long hydraulic residence time of the two arms of the reservoir will remove nutrients upstream of the main body, …
Quantitation of Endogenous Nucleotide Pools in Pseudomonas aeruginosa
Nucleotide pools were extracted and quantified from Pyr^+ and Pyr^- strains of P. aerucjinosa. Strains were grown in succinate minimal medium with and without pyrimidines, and nucleotides were extracted using trichloracetic acid (TCA; 6% w/v). The pyrimidine requirement was satisfied by uracil, uridine, cytosine or cytidine. Pyr^- mutants were starved for pyrimidines for two hours before nucleotide levels were measured. This starvation depleted the nucleotide pools which were restored to wild type levels by the addition of pyrimidines to the medium. When the pyrimidine analogue, 6-azauracil, known to inhibit OMP decarboxylase, was added to cultures of the wild type strain, the uridine and cytidine nucleotides were depleted to near zero. Thus, the nucleotide pool levels of Pseudomonas strains can be manipulated.
The Suspension Cultivation of, and the use of Alternative Cell lines for the In Vitro Cultivation of, Treponema Pallidum Subspecies Pallidum
This study had two objectives: to achieve suspension cultivation of Sf1Ep cells and to develop procedures for achieving the replication of T. pallidum in those cell cultures. Sf1Ep cells have been the sole cell line used for the in vitro cultivation of T. pallidum. A study was undertaken to determine if other cell lines can support growth of T. pallidum. Rabbit skin fibroblasts (RAB-9), nude mouse ear (NME) cells, and normal rebbit testis fibroblasts (RT) were compared to Sf1Ep cells for their ability to support in vitro multiplication of T. pallidum. RAB-9 cells supported multiplication of treponemes equal to that of Sf1Ep cells. NME and RT cells also supported growth but to a lesser extent than Sf1Ep cells. Utilization of alternative cell lines may lead to improved in vitro growth of T. pallidum including possible serial passage.
Characterization of the Self-Replicating Kirsten Murine Leukemia Viral DNA: Replication and Tetracycline Resistance
This research project deals with the characterization of self-replicating Kirsten murine viral DNA. The replication of this viral DNA and tetracycline resistance conferred to bacteria by this viral DNA will be studied. The restriction endonuclease and Southern blot analysis revealed a fragment of pBR322 from the Hind III and Pst I site that is located in the 3' end of the MLV-K:E molecule. Single stranded sequencing of the two terminal ends of this fragment verified that the 3' end of MLV-K:E contains identical sequence homology to pBR322. The presence of this pBR322 fragment explains the unusual properties of the MLV-K:E molecule. However, tetracycline resistance is less in E. Coli containing MLV-K:E than E. coli containing pBR322 as determined by zone of inhibition assay. This may be due to alteration in the promoter region of the tetracycline gene.
Interrelational Laboratory Information System for Data Storage and Retrieval
The necessity for a functional user friendly laboratory data management program has become evident as the quantity of information required for modern scientific research has increased to to titanic proportions. The required union of strong computer power, ease of operation, and adaptability have until recently been outside the realm of most research laboratories. Previous systems, in addition to their high cost, are necessarily complex and require software experts in order to effect any changes that the end user might deem necessary. This study examines the Apple Macintosh computer program Hypercard as an interactive laboratory information system that is user-friendly, cost effective, and adaptable to the changing demands within a modern molecular or microbiology.
Measurement of Feedback Inhibition In Vivo and Selection of ATCase Feedback Altered Mutants in Salmonella typhimurium
Aspartate transcarbamoylase (ATCase; encoded by pyrBI genes) is one of the most studied regulatory enzymes in bacteria. It is feedback inhibited by cytidine triphosphate (CTP) and activated by adenosine triphosphate (ATP). Much is known about the catalytic site of the enzyme, not nearly as much about the regulatory site, to which CTP binds. Until now a positive selection for feedback-modified mutants was not available. The selection we have developed involves the use of a pyrA deletion in S. typhimurium. This strain lacks carbamoylphosphate and requires both a pyrimidine and arginine for growth. In this strain citrulline is used to satisfy the pyrimidine and arginine requirements. The minimal flow through the pyrimidine pathway from the citrulline-produced carbamoylphosphate is exquisitely sensitive to feedback control of ATCase by CTP. By elevating the CTP pool, via exogenous cytidine, in a strain that also contains a cytidine deaminase mutant (cdd) growth can be stopped completely, indicating 100% inhibition. It was therefore possible to measure in vivo feedback inhibition of ATCase among the citrulline users and to isolate a family of ATCase regulatory mutants with either modified or no response to effectors.
Effects of Water Quality, Instream Toxicity, and Habitat Variability on Fish Assemblages in the Trinity River, Texas
The Trinity River flows through the Dallas-Ft. Worth Metroplex in north central Texas where it receives effluents from numerous point sources including seven large regional wastewater treatment facilities. Historically, the Trinity River has been impacted by massive wastewater loadings which often constitute > 80% of the total river discharge during low flow periods. Normally, high mass loadings correspond to the summer months, compounding the effects of a naturally stressful period, characterized by high temperatures and low dissolved oxygen concentrations. Samples from 12 stations were collected quarterly over an 18 month period from the Trinity River and two tributaries. Water samples were analyzed for a variety of water quality variables, including metals, priority pollutants, pesticides, and general water quality parameters. Water samples were also tested for acute and subchronic effects with several test species. Fish were collected at each station and assemblages were characterized using traditional classification techniques and the Index of Biotic Integrity. In addition, sediment samples were assessed for toxic effects which could have adversely impacted fish recruitment and in situ biomonitoring experiments were performed. Quantitative habitat characterization analyses were performed to gain additional information that could possibly explains differences in fish assemblage structure related to habitat variability. Data were analyzed using regression, univariate, multivariate, and descriptive statistical techniques and new approaches for analyzing impact assessment data were discussed. Results indicated that the most substantial impacts on fish assemblages were confined to a segment of the river where a sequence of point sources, in close proximity to each other, were overloading the river's capacity to sufficiently dilute and/or detoxify the effluent. Data also indicated the presence of episodic toxicity from nonpoint sources. In addition, toxic effects in sediment samples and differences in habitat were detected and may have contributed to measured differences among fish assemblages in the Trinity River.
Opioid/Adrenergic Interaction in Regulating Canine Cardiac Function
Opioid/adrenergic interactions were studied to evaluate two hypotheses: (1) naloxone potentiates the effect of epinephrine on cardiac contractility by increasing circulating epinephrine concentrations; and (2) endogenous and exogenous opioids alter left cardiac nerve stimulationinduced norepinephrine release and cardiac function. A canine isolated heart-lung preparation was used for the first study. Plasma epinephrine was determined and myocardial epinephrine uptake was calculated during intravenous epinephrine infusion. Naloxone (4 mg) was given and the epinephrine infusion was repeated. Naloxone increased cardiac contractility, coronary blood flow, and the coronary sinus epinephrine concentration. When coronary blood flow was subsequently held constant (100% above resting), naloxone increased only contractility. This result indicated that the previously observed increase in coronary sinus epinephrine was flow dependent. Corticosterone (an uptake II blocker) was employed as a positive control. Corticosterone increased the contractile response to epinephrine, but unlike naloxone, corticosterone was accompanied by a clear decrease in myocardial epinephrine uptake. The stereospecificity of the response to naloxone was investigated and (+) naloxone equaled or exceeded (-) naloxone in potentiating the inotropic effect of epinephrine. In the second study, the left cardiac nerve was isolated and electrically stimulated in intact dogs. Norepinephrine overflow gradually declined during successive control stimulations. Pretreatment with naloxone (100 Mg/kg) prevented or delayed the decline. An intracoronary dynorphin 1-9 infusion (2 nmol/min/kg for 20 minutes) reduced both norepinephrine overflow and cardiac performance, and both effects were prevented by pretreatment with naloxone (100 /xg/kg) . To summarize, naloxone potentiated the inotropic effect of infused epinephrine without altering circulating epinephrine concentrations or myocardial epinephrine uptake. This effect of naloxone was not stereospecific and probably not mediated through a traditional opiate receptor. Endogenous and exogenous opioids inhibited the left cardiac nerve stimulation-induced norepinephrine overflow, suggesting that opiate receptors may regulate cardiac excitability by modulating norepinephrine release.
Characterization of Pyrimidine Biosynthesis in Pseudomonas putida Using Mutant and Wild Type Strains
The biosynthesis of pyrimidines in Pseudomonas putida was investigated. In this study, pyrimidine requiring mutants were isolated by conventional mutagenesis and enrichment. The strains required exogenously supplied pyrimidines for growth and were found by enzyme assays to be deficient for the product of the pyrB gene encoding the enzyme aspartate transcarbamoylase. None of the intermediates of the pathway could supply the auxotrophic requirement of the strain; only preformed pyrimidines, metabolized via salvage pathways could suffice. Pyrimidine limitation in the mutant caused a slight but significant fifty per cent increase in expression of all the de novo biosynthetic enzymes. Pyrimidine starvation's effect on nucleotide pool levels was examined in the mutant and caused a marked swelling of the purine nucleotide pools.
Adenosine and Down-Regulation of Myocardial Oxygen Demand
This investigation studied the physiological means by which myocardium can survive and function properly when oxygen supply is limited and cannot initially match oxygen demand. The effects of isoproterenol (ISO) stimulations during low coronary perfusion pressure or hypoxemia on myocardial oxygen demand, work, and oxygen utilization efficiency were investigated.
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