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.
The applicability of an isotopically labelled assay system to determine the lipase production in Pseudomonas aeruginosa was evaluated. Supernatant from cultures of Pseudomonas aeruginosa grown in a medium containing olive oil was incubated with a substrate containing labelled trioleate. Fatty acids were isolated by means of a liquid-liquid partition system. Enzyme activity was determined by measuring the amounts of free fatty acid by liquid scintillation counting. Findings indicate that the isotopicallylabelled, liquid-liquid partitioning assay is reliable, sensitive and adaptable to rapid assay conditions. It was also determined that different strains of Pseudomonas aeruginosa produce varying amounts of lipase. Partial purification of supernatant by gel filtration produced two protein peaks showing enzymatic activity.
Starch gel electrophoresis was used to compare 14 proteins encoded by 15 loci for seven species of the family Icteridae. A close genetic relationship among these species was classified into three groups. The Agelaiine group contained Agelaius phoeniceus, Sturnella magna, and S. neglecta. The Quiscaline group contained Euphagus cyanocephalus, Cassidix mexicanus, and Quiscalus quiscula. Molothrus ater, the most divergent, was placed in a separate group. Divergence times for the seven species were compared to the literature. Heterozygosity of the seven populations of the two species of Sturnella were compared to determine factors influencing their divergence. Two factors proposed were heterosis in S. neglecta and possible hybridization between S. neglect and S. magna.
Electrophoretic techniques were utilized for the demonstration of variation in 22 proteins from 24 natural populations of four species ( G. bursarius, G. pinetis, G. arenarius and G. personatus ) of the Geomys complex of pocket gophers. Of the 24 structural loci , 19 were considered to be polymorphic. Five of the six esterases contributed greatested to the polymorphism while non-esterase proteins generally showed low values. In the GeoMys complex of pocket gophers in this study,selection appeared to be the most important influence on genetic structure with some evidence of random drift in two of the four species. Populations of G. arenarius and G. personatus had the highest average interspecific genetic similarities to G. bursarius and . pinetis was the most divergent. Biochemical evidence supports the phylogeny of Geomys based on morphological and fossil data.
Three unusual amino acids, y-amino-n-butyric acid, pipecolic acid, and 4-hydroxypipecolic acid, and an uncommon dipeptide, y-glutamyltyrosine, have been isolated and characterized from the seeds of members of the genus Sophora. Structural proof of these compounds was carried out by paper chromatography, thin-layer chromatography, column chromatography on amino acid analyzer, infrared, nuclear magnetic resonance, mass spectrometry, and C, H, N analysis. The presence and absence of these compounds was used as a criterion for the classification of 23 species of the genus Sophora. A phylogenetic classification which seems to follow the morphological taxonomy of this genus was carried out on the basis of seeds that contained pipecolic acid, those which did not contain pipecolic acid, and plants which contained both pipecolic acid and 4-hydroxypipecolic acids. Another chemical classification was also introduced based on the presence and absence of y-amino-n-butyric acid and y-glutamyltyrosine.
This investigation has determined the presence of biological nitrogen fixation in two reservoirs in the southwestern United States: Lake Arlington and Lake Ray Hubbard. Subsequent tests have gathered baseline data on the effects of various biological, chemical, and physical parameters on in situ nitrogen fixation in these reservoirs. Of specific importance is the relationship between nitrogen fixation arid occasional blooms of blue-green algae which produce such problems as testes and odors in these water-supply impoundments.
The central objective of the study was to fractionate sedimenting organic materials according to their source (allochthonous or autochthonous) and ultimately to determine the degree of biodegradability of contributions from either source with particular reference to activities at the mud-water interface.
Liver cells from lymphosarcoma-bearing DBA/1J mice were shown, by parabiotic culture with normal liver cells from isologous mice, to elaborate an agent which could pass a 25 mu filter and transform the normal cells to a malignant state.
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.
This study (1) quantitatively compared steroid production in cultured Y-l mouse adrenal tumor cells exposed to Camel and Carlton-smoke derived residues, and (2) localized the effects in the cell. Basal steroid production was increased by Camel residues but not by Carlton, while ACTH stimulation was interfered with by both residues. Camel basal stimulation was comparable to that of cAMP, and was abolished by Cytochalasin D. The stimulation was also comparable to that of cholera toxin, which activates adenyl cyclase. Results indicate that residue components dissolve in the membrane stimulating adenyl cyclase at a point similar to or before that utilized by cholera toxin for its stimulating effect.
To better understand abiotic dynamics in Southern reservoirs receiving heated effluents, water was analyzed before and after impoundment in 330 ha North Lake. Macronutrients, metals, and chlorinated hydrocarbons were measured. Concentrations of nutrients and metals in sediments were quantified in this 2 yr study. River water prior to impoundment contained 16 times more total phosphorus, and supported 23 times more Selenastrum capricornutum cells in an algal assay than reservoir water. The reservoir has essentially no drainage and since evaporation is high, the concentrations of many dissolved solids have increased since the reservoir was filled in 1958. North Lake is now phosphorus limited. Apparently altered chemical equilibria have caused precipitation or adsorption of phosphorus with calcium and iron.
This study is concerned with a critical comparison of the passive transfer mechanisms of tuberculin and chemical contact hypersensitivities in the guinea pig by use of a four phase experimental approach.
Several final sewage effluents from the Denton Disposal Plant were demonstrated to contain Poliovirus types II and III. Pleated encapsulated filters at pH3.5 enhanced the recovery of the Poliovirus at a higher tier in comparison with nitrocellulose filter (Millipore) and glass fiber filter of pore size 0.45u. This thesis explores problems that face us today in our quest to eliminate viral pathogens from the natural and waste water needed for human, domestic, and industrial consumption. Preliminary experiments concern the use of immunofluorescence, and immunodiffusion techniques as a means of poliovirus identification, which invariably suggests that these techniques may be useful as rapid screening procedures of water samples for presence of potentially pathogenic viruses.
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.
Analysis of larval fish collected at four stations in a 330-ha cooling reservoir indicated Dorosoma spp. were most numerous at all stations, followed by Lepomis spp. and Percina Macrolepida. Largest numbers and greatest diversity of larval fish were found at the station least affected by thermal effluent; the mid-lake station provided the smallest numbers and least diversity. The two warmwater stations were intermediate, with similar numbers and diversity. Diversity and abundance of zooplankton between stations were similar to those of fish. The most abundant zooplankter (Bosmina) was generally selected against by Dorosoma, Lepomis and Micropterus spp. larvae except when the larvae were quite small ((10mm). Cyclopoid copepods were most often selected by all larvae.
The purpose of this study was to extend our understanding of the ecological relationships of P. aeruginosa by investigating the differences or similarities between the strains of this organism found in sewage and those found as pathogens in human infections. This research was approached by comparing the serological types of P. aeruginosa isolated from sewage contaminated waters in Argentina (South America) to those isolated from sewage contaminated waters in Texas. They were typed with sera obtained using P. aeruginosa isolated from human infections. The data obtained revealed that bacteria isolated from sewage in Texas and from soil and water in Argentina are antigenically similar to those isolated from human infections.
Bacteria classified in the family Methylomonadaceae must derive their carbon from one-carbon compounds. They are characterized by the possession of internal membranes of two types. Type I membranes are layered and fill the middle of the cells while type II membranes form concentric layers around the periphery of the cells. Also, there are two metabolic pathways by which the methylobacteria assimilate one-carbon compounds. Further evidence of this dichotomy was sought by DNA-DNA saturation hybridization of DNAs from both types of methylobacteria. Very low DNA-DNA homology was seen between types I and II or within the types. It was not possible, therefore, to correlate the degree of genetic relatedness with either the nature of the internal membranes or the pathway of carbon assimilation.
Drumming was recorded for 11 of 13 Nearctic stonefly species, representing 4 families. Both male and female signals were obtained from 5 species, and were either 2-way or 3-way communications. Signals were species-specific; those of males and females varied from 3-39 and 1-14 beats/ signal, respectively. Duration of male signals varied from 105-8,016 ms; those of females, except Perlinella drymo (1 beat), varied from 402-1318 ms. Signals among related taxa showed greatest similarities. Duration of male signals of Perlinella drymo became progressively shorter at each of 4 temperatures from 7-29 0C. Females of Perlinella drymo would only repeatedly answer male signals recorded at near their own temperature, and would not repeatedly answer recorded male signals of 8 other species.
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 …
The effect of microwave radiation on soil bacteria in situ has been studied in both lab and field conditions. Radiation and thermal profiles show that heterotrophic bacteria, spores, fungi, and actinomycetes were not affected by total microwave radiations over the range 0 to 80 seconds of exposure at a net input of 1 KW of intensity. Nitrogen-fixing bacteria and nitrifying bacteria were also resistant to these doses. The soil microorganisms were inactivated as a function of microwave radiation in the range of 80 to 480 seconds of exposure to 1 KW of continuous radiation. By studying the relationship between temperature generated in dry and wet organisms and the pattern of destruction of inoculated bacteria by microwave radiation, it was found that inactivation was a function of cell hydration. It also revealed that bacterial cells do not absorb microwave energy and that the lethal effect of microwaves is due to direct energy transfer to cell water and the temperature increase of the suspending medium.
Studies were evaluated on the effects of known growth factors on the growth and carotenogenesis of Corynebacterium species strain 7ElC. The complex medium, Tryptic Soy Broth,was found to stimulate growth and production of more pigment in the light and in the dark than did a mineral salts-glucose medium. A complete amino acid mixture added to LSG enhanced carotenogenesis in the dark in Corynebacterium 7ElC, while B-vitamins retarded carotenogenesis. No absolute requirement for one or more amino acids was found,indicating a multiple amino acid requirement. The fewest amino acids found to stimulate carotenogenesis in the dark were a combination of those in the Serine and Histidine families which include serine, glycine, cysteine, and histidine.
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.
It was the purpose of this study to investigate the effect of various concentrations of IAA on the nucleic acids of Chlorella pyrenoidosa TX 7-11-05. The time during the life cycle when the greatest effect occurred was investigated by the use of synchronous cultures.
The role of operant behavior in the metabolism of brain 5-hydroxytryptamine (5-HT) turnover was investigated. Two and one-half hours following the administration of 150 mg/kg of para-chlorophenylalanine (PCPA), a specific inhibitor of tryptophan hydroxylase, levels of 5-HT were compared in sedentary and performing rats. Whole brain levels of serotonin were reduced in both responding and sedentary animals; however, differences between these groups were not statistically significant. The drug induced decrease in 5-HT levels was accompanied by a significant decrease in session responding. The degree of suppressed responding could be correlated with the level of 5-HT following PCPA, suggesting that the metabolism of serotonin is in part modulated by the rate of responding as maintained by the operant schedule.
The effects of various concentrations of 2-chloroethylphosphcnic acid (Ethephon), an ethylene-releasing compound, on the total protein, deoxyribonucleic acid (DNA), and ribonucleic acid (RNA) levels in Scenedesmus quadricauda IU 614 were investigated.
This investigation was concerned with characterizing a tumor line induced and maintained in this laboratory. Various chemical assays, cell counts, and electron microscopy were the methods employed to characterize the blood of mice bearing the tumor at days 3, 6, 9, and 12 after injection of the 1.2 x 10^8 tumor cells.
This investigation was concerned with characterizing effects of this tumor line on lipid metabolism in DBA/lJ mice and serum protein levels and cellular changes in DBA/lJ and Swiss white mice. Total lipids, lipid phosphorus, neutral lipids, and changes in fatty acids were determined in liver, spleen, skin, and tumor of DBA/lJ mice bearing the lymphosarcoma at various days after injection of tumor cells.
The Cardiac Profile, a pattern of serum enzyme changes seen within seventy-two hours after an AMI, is diagnostic aid for detecting occurrence of infarcts. The effects of exercise stress on the Cardiac Profile aid clinicians in avoiding diagnostic errors in patients immediately after exercise. Five male volunteers ran from six to ten miles. Serum enzyme levels were monitored serially three days before and five days after stress. Enzyme activity was determined spectrophotometrically and electrophoretically. Significant increases in total CPK and LDH were seen. An LDH 'one-two flip' occurred eight hours after exercise. No MB-CPK was found following the run.
My study of the effects of carbaryl in aquatic systems under controlled laboratory conditions emphasized four major objectives: (1) to determine the acute toxicity of carbaryl to the herbivorous adult and immature Trichocorixa reticulata (Guerin)(Hemiptera: Corixidae), and to the omnivorous larvae of Glyptotendipes barbipes (Staeger) (Diptera: Chironomidae) under static bioassay; (2) to adapt a quantitative method of analysis for carbaryl in water and whole insect tissue extract; (3) to measure the accumulation of the insecticide by G. barbipes under static exposure; and (4) to quantify the uptake and loss of carbaryl by G. barbipes under daily-renewed sublethal dosages.
The literature on the effects of phytohormone on algae is clouded with contradictory reports. Reports have been published which substantiate and deny the effects of phytohormones in enhancing the growth and developmental processes in algae. The overall aim of this study was to investigate the response, if any, of the phytohormones indole-3-acetic acid (IAA), gibberellic acid A3 (GA) and kinetin on the physiology of the green alga, Scenedesmus quadricauda. Results obtained for the uptake of 14^C-IAA an(j l4C-kinetin by Scenedesmus strongly support the presumption that the alga does not absorb the hormones. The retention of the phytohormones by the alga is due to adsorption, and is independent of hormone concentration. Most of the label was adsorbed by the outer pectic layers of the cell wall.
Ribavirin, a synthetic nucleoside, was found to inhibit the replication of Rous sarcoma viruses (RSV) and subsequent cell transformation in chick embryo fibroblasts (CEF). It also blocked the transformation of normal rat kidney (NRK) cells infected with temperature-sensitive mutants of RSV. The action of Ribavirin was found to be reversible as removal of the drug from the NRK cells reversed the effects on cell transformation. Ribavirin appears to have a static effect on cell growth of both NRK and CEF cells. In addition, guanosine, xanthosine and inosine altered the effect of Ribavirin on cell growth.
Laboratory studies conducted at 5, 15, 25, and 35 C measured changes in gilling rates and oxygen consumption of green sunfish in response to exposure to bentonite clay suspensions. The tests indicate that gilling rates are not affected by bentonite clay suspensions below 2125 FTU at 5 C, 1012 FTU at 15 C, and 898 FTU at 25 C. At turbidity levels exceeding 1012 FTU at 15 C and 898 at 25 C, gilling rates increased 50-70%. Tests were inconclusive at 35 C. Oxygen consumption rates were found to be unaffected by turbid suspensions below 3500 FTU at all four temperatures. Evidence suggests that increased gilling rates under highly turbid conditions are a means of compensating for reduced respiratory efficiency and a strategy for maintaining a constant oxygen uptake. Evidence indicates that the cost of increased gilling rates is probably met by a reduction in activity.
Electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain their genetic integrity throughout their ranges. their genetic integrity throughout their ranges.
The genetic structure of 49 natural populations of four species (P. attwateri, P. boylii, P. pectoralis, and P. polius) of the Peromyscus boylii species group was analyzed through application of chromosomal and electrophoretic techniques. Chromosomal variation within and among populations of the boylii species group was analyzed from 178 specimens. Electrophoretic techniques were utilized for the demonstration of variation in enzymes and other proteins encoded by structural loci and applied to the study of the evolution of the boylii species group by estimation of levels of genetic heterozygosity within populations, estimation of degree of genetic similarity between conspecific populations and between species, and determination of patterns of geographic variation in allelic frequencies and levels of heterozygosity. Six distinct chromosomal patterns were observed among the populations of the four species of the boylii species group. All specimens had a diploid number of 48 and the major difference in chromosomal morphology was in the number of pairs of large to medium biarmed autosomes. Little or no chromosomal variation was observed in three species (attwateri, pectoralis and polius), but considerable chromosomal variation occurred among populations of P. boylii. Generally, the chromosomal variation in P. bylii was between allopatric populations, with each chromosomal pattern limited to a recognized subspecies. Polymorphism was observed in two populations. The polymorphism observed in P. polius was the result of pericentric inversion involving the smallest pair of metacentric autosomes. The polymorphism observed in P. bolii cileus was interpreted at the result of gene flow between P. boylii rowleyi and P. boylii spicilegus. In addition to chromosomal evidence, analysis of electrophoretic data demonstrated and suggested effective gene flow between the chromosomal forms of P. boylii. Electrophoretically demonstrable variation was analyzed in 11 proteins encoded by 17 autosomal loci. Of the 17 structural loci, 11 were polymorphic in one or more …
Electrophoretic variation in 18 proteins encoded by 20 autosomal loci was used to compare the genetic relationships of 19 natural populations representing three species of the subgenus Neotoma. Of the 20 loci examined nine were monomorphic and fixed for the same allele in all populations. No more than seven loci were polymorphic within a single population. Genetic variability was expressed as the proportion of loci heterozygous in the average individual of a population. Heterozygosity in the three species of Neotoma studied averaged 0.078, a value within the range reported for other rodents. Although the levels of heterozygosity seen in Neotoma could not readily be explained, the variation may be attributed to ecological factors. The three species of Neotoma were compared on the basis of genetic similarity and found to form a close taxonomic unit, probably semispecies. Divergence times were obtained for the three species and found to compare well with divergence times obtained from fossil data. In general, the three species have diverged within the last 112,000 years during the Wisconsin glacial period.
This work concerns itself with essentially four experiments: (1) the cecum-injective-infection experiment; (2) the anus-injective-infection experiment; (3) the mouth ingestive-infection with larvae, and (4) the mouth ingestive-infection with the flesh of infected rats.
This study was made to further define the trophic dynamics of Fundulus notatus by determining its ration composition under natural conditions, measuring feeding selectivity under various laboratory conditions of prey-species composition and availability, and determining the efficiencies with which F. notatus utilizes ingested chironomid larvae.
Gut contents of 2,500 stonefly nymphs, comprising 10 species, from the Gunnison and Dolores Rivers, Colorado were examined from Dec., 1974-Oct., 1975. Perlidae species were carnivorous feeding primarily on chironomids, mayflies and caddisflies. Seasonal patterns of ingestion and preference varied among species and predator sizes and between rivers. Early instar polyphagous species utilized detritus in the fall, eventually shifting to carnivorous habits as they grew through winter-spring. Pteronarcids fed predominantly on detritus. Dietary overlap of predators was greatest in the Gunnison River, with subtle mechanisms such as prey species and size selectivity, temporal succession and seasonal shifts to detritus-plant material in some, providing reduction of competition. A more complete partitioning of prey resources was evident in the Dolores River.
The genetic structure of 26 natural populations of three species (S. tridecemlineatus, S. mexicanus, and S. spilosoma) of the Ictidomys subgenus of ground squirrels was analyzed using chromosomal and electrophoretic techniques. Chromosomal variation was not observed in S. mexicanus, and only slight karyotypic variation was found in the other two species. Chromosomal evidence indicated hybridization between S. tridecemlineatus and S. mexicanus, placing these species within the classical definition of semispecies. Analysis of electrophoretic variation at 29 genetic loci indicated close genetic relationships between these species. Evolution in Ictidomys appears to be linked with Pleistocene events, and speciation appears to have occurred within the last 155,000 years.
Normal ranges of values for hematological parameters of bluegill gathered seasonally from three lakes were determined. Sexual, seasonal, and inter-lake variations were found. Effects of 2-wk exposure to turbidity on blood parameters included an increase in rbc size and a decrease in small lymphocytes. Effects of 3-hr exposure were increases in rbc count, hemoglobin, and pH and decreases in PG2 and large lymphocytes. The effects of 0.44 and 0.88 ppm chloramines were an increase in blood pH, a decrease in MEV, and severe spastic reactions resulting in loss of equilibrium or death in 90% of the fish. Effects of Flexibacter columnaris included an increase in transformed lymphocytes and a decrease in small lymphocytes.
The AKR strain of mice have a genetic trait for spontaneous development of lymphocytic leukemia. In this study, leukemic mice were found to have significantly larger (p<0.01) thymuses and spleens than preleukemic mice. The enlarged leukemic tissues were densely packed with a light staining cell, with a hollow-appearing nucleus. Tissues from preleukemic mice were observed to be infiltrated with a smaller, darker-staining lymphocyte. Fluorescent antibody staining was done on preleukemic and leukemic tissues, using three antisera against murine lymphocyte theta antigen, and an antiserum against murine IgG. Significantly brighter fluorescence, (p <0.05) with theta-specific antisera, was found in leukemic thymuses,spleens, and kidneys than in the same preleukemic tissues. Leukemic tissues had significantly brighter fluorescence (p <0.05) than preleukemic tissues with IgG antiserum.
The rigid peptidoglycan layer of the cell wall is responsible for maintaining the structural integrity of bacteria. Antibiotics such as penicillin exert their anti-bacterial effect by inhibiting synthesis of peptodoglycan, and enzymes such as lysozyme destroy cell integrity by hydrolyzing specific bonds in the interior of this macromolecule. Defective cells can no longer withstand the high turgor pressure within the cell because they are no longer protected by a rigid wall and tend to become fragile and spherical or irregular in shape. While all bacteria are pleomorphic under certain conditions which do not normally affect other bacteria. This is exemplified by the pleomorphic growth of Azotobacter in nutrient agar or peptone-containing medium. The purpose of this investigation was to study the nature of peptone-induced pleomorphism of Azotobacter. The first phase of study dealt with the effects of poptone on the growth and morphology of A. vinelandii. Many diverse froms were observed in peptone-containing media, but it was shown that all cell types were related to the "fungoid" family of pleomorphic cells. Although Azotobacter failed to accumulate detectable levels of cell-wall precursors in response to glycine treatment, it was shown that glycine acted only on metabolically active cells. In addition, incorporation of glycine into cell wall of Azotobacter was not required for induction of pleomorphism. Methionine and aspartic acid, and to a lesser degree alanine and isoleucine, were found to competitively inhibit glycine toxicity.
A model for the study of the relationship of immunity to cancer is found in AKR mice which harbor Gross virus. This genetically transmitted virus is present in a latent form for months before it spontaneously induces leukemia. Many investigators have demonstrated near normal humoral responses, but abnormal cellular immunity in the preleukemic animal. With increasing age, pathology of the disease is expressed, reflecting diminished immunity. In this study, the ontogeny of humoral antibodies of AKR/J and SWR/J mice was assayed by microagglutination techniques in response to thymus-independent, thymus-dependent, and solubilized antigens. Simultaneous injections of thymusdependent and -independent antigens provided data suggesting an impaired humoral response in the AKR mouse.
The problem with which this investigation is concerned is that of determining the nature of events leading to the change. of normal cells into malignant cells. The design of the study is multi-phasic: (A) to establish the presence or absence of an oncogenic virion, (B) to demonstrate by use of the electron microscopy any ultracellular alteration in malignant or transformed tissues, (C) to investigate the nature of the transforming agent in the murine lymphosarcoma, and (D) to employ various methods to demonstrate cellular transformations in vivo and in vitro. It is concluded that the transforming and tumorinducing agent in this' investigation was not a virion, but an infectious ribonucleic acid genome or a segment of a viral genome which had become integrated into the genome of the mouse cells. The vision has lost its ability to form a protein coat; therefore it is not demonstrable as a virion. But the ribonucleic acid is able to infect other cells and transform them from normal to neoplastic tissues.
The purpose of this study is to provide a qualitative, detailed description of individual and social behavior in a free-living population of thirteen-lined ground squirrels. Behavioral differences in relation to various periods of the annual cycle are also evaluated.
In the southwestern United States there is a delicate balance between the existing grasslands and the rodent fauna. The purpose of this investigation was to determine the influence of secondary succession of native grasslands upon the ecology and distribution of small rodents. Two methods of determining the rodent species were plot quadrates and trap lines using Sherman live traps.
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.
A procedure for the isolation of malic enzyme from muscle tissue of the roundworm Ascaris suum is described. The fractionation method yields relatively large quantities of the enzyme,with a specific activity of fifteen moles of malate converted to pyruvate and carbon dioxide per min per mg at 25º. Homogeneity was established with analytical ultracentrifugation, zone electrophoresis, isoelectric focusing, and rechromatography. The molecular weight of the enzyme was 250,000, and it is dissociated under several conditions into four identical monomers of 64,000 daltons. The enzyme exists as a single electrophoretic form and prefers manganous and NAD over other cations and NADP. Ammonium sulfate competes with manganous for the active site and titration with DTNB yields eight thiol groups per mole. Titration of the first four thiol groups is accompanied by a complete loss in enzyme activity. Equilibrium dialysis, product inhibition, and initial velocity studies suggest a rapid-equilibrium random sequential mechanism for the Ascaris suum malic enzyme. The presence of 1.3 binding sites per subunits was determined for L-ma late. Antisera prepared against A. suum malic enzyme reacted to a small extent with the NAD malic enzymes from two free-living nematodes, Panarellus redivivus and Turbatrix aceti. A correlation coefficient of 0.911 was obtained upon comparing the amino acid composition of A. suum and E. coli malic enzymes. Some sequence homology is predicted between these malic enzymes. The physiological interpretation favors the binding of malate initially, with the subsequent addition of NAD to the enzyme.
This problem was concerned with determining the total lipid content and individual lipid composition of the larvae of a local chironomid, Glyptotendipes barbipes (Staeger).
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.
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Each of the U.S. States listed note their name and the number of records that will be limited down to if you choose that option.
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Each of the Counties listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the Years listed note their name and the number of records that will be limited down to if you choose that option.
The list can be sorted by name or the count.
This dialog allows you to filter your current search.
Each of the Months listed note their name and the number of records that will be limited down to if you choose that option.
The list can be sorted by name or the count.
This dialog allows you to filter your current search.
Each of the Discipline listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the Degree Level listed note their name and the number of records that will be limited down to if you choose that option.