Thesis (Ph. D.)--Rutgers University, 2008. / "Graduate Program in Oceanography." Includes bibliographical references (p. 85-92).

Thesis (Ph. D.)--University of Virginia, 1998. / Includes bibliographical references (p. 314-323). Also available online through Digital Dissertations.

Samples of excrements for parasitological investigation were obtained in two year period 2011 and 2012 on three sheep farms and two goat farms in South Bohemia (a farm conventional, an organic and converting to an organic farming system). A total of 400 samples were examined using four parasitological methods. Thirteen species of gastrointestinal nematodes and one species of Protozoa were recovered. In farms Coccidia Eimeria spp. was the most diagnosed. Results revealed that goats were 1,8 times more often infected with parasites than sheep (x2 = 6,274; d. f. = 1; p = 0, 00576; OR = 1,82). Animals younger 6 months were 3 times more often infected with Eimeria than older ones (x2 = 17,174; d. f. = 1; p = 0,00003; OR = 3,16). Goats were 11 times more often infected with parasites in winter than sheep (x2 = 5,8174; d. f. = 1; p = 0,0050; OR = 10,78). Goats were 2 times more often infected with lungworm infection than sheep (x2 = 8,407; d. f. = 1; p = 0,0019; OR = 1,99). A statistically significant difference in infectious contamination between conventional and an organic system bred animals was not discovered (x2 = 0,0145; d. f. = 1; p = 0,452; OR = 1,05).

This investigation is based upon the occurrence of oral protozoans among 25 periodontalclasial patients in Stockton, California. It is concerned, in part, with the correlation of infections with age, sex and oral health of the host and, in part, with culture techniques. The specific cultivation of Trichomonas tenax was explored in an effort to employ an improved experimental medium. Trichomonas tenax and Endamoeba gingivalis are the only protozoans known to occur commonly in the human mouth. Distribution is cosmopolitan and there are no known endemic areas. Incidence of these two protozoans, among periodontalclasial patients, has not been reported since the study made by Jirovec, Bertos, Mezl, and Novack (1942).

No description available.

The effect of competing food sources on termite consumption of hexaflumuron bait and subsequent mortality was examined. Also, the effect of hexaflumuron on the termite gut fauna was evaluated to determine if hexaflumuron could kill termites via a secondary mode of action. Hexaflumuron consumption in no-choice and choice tests was evaluated at 2d and 5d. Total diet consumption was not different between the treatment groups. Hexaflumuron consumption was reduced by a factor of 3 in the presence of a competing control diet and reduced by a factor of 57 in the presence of an inulin diet. In the choice test, termites preferred inulin over hexaflumuron. Termite mortality after hexaflumuron consumption was quantified at 5d, 15d, 20d, 25d, and 35d in three treatment groups. Mean mortality for termites fed only hexaflumuron diet was significantly higher than termites fed only control diet. Mean mortality for termites given a choice was no different than mortality for termites fed only hexaflumuron or control diet. LT50s for termites fed control diet, hexaflumuron diet, or both diets in the choice test, were 24.4d, 18.7d, and 20.6d, respectively. The choice test LT50 did not differ from the LT50 of either no-choice test. Termites fed only hexaflumuron diet had an earlier LT50 than termites fed only control diet. The effect of hexaflumuron on gut fauna survival was evaluated at 5d and 15d. No significant differences were found in total numbers of protozoa in termites fed either hexaflumuron or control diet. Pyrsonympha was the only protozoa significantly reduced by hexaflumuron consumption. / Master of Science

Durante o ciclo de vida da Leishmania, amastigotas vivem no interior de fagolisossomas de células fagocíticas de hospedeiros vertebrados, enquanto promastigotas vivem no interior do vetor invertebrado. Proteases intracelulares como as caspases são as principais efetoras no processo apoptótico. Metacaspases (MCAs) são formas evolutivas distantes das caspases de metazoários, presentes em protozoários, plantas e fungos, e vistas como potenciais alvos para combate dos parasitas sem prejuízo do hospedeiro. Ligantes e moduladores das metacaspases são até hoje desconhecidos. O Phage Display é uma técnica baseada na expressão de proteínas sintéticas nos capsidíos de fagos, usada com o propósito de selecionar ligantes de proteínas, células ou tecidos. Produzimos a metacaspase recombinante de Leishmania L. amazonensis e aplicamos Phage Display para buscar peptídeos ligantes dessa enzima. Esses peptídeos permitiram identificar potenciais proteínas ligantes da MCA, como quinases e cinesinas, que fornecem informações sobre a regulação e controle de sua atividade. Futuramente testaremos se peptídeos ativadores da MCA poderão induzir apoptose do parasita e serem usados como drogas para o tratamento da leishmaniose. / During its life cycle, Leishmania amastigotes live inside phagolysosomes of phagocytic cells of vertebrate hosts, while promastigotes live inside the invertebrate vector. Intracellular proteases such as caspases are key effectors in the apoptotic process. Metacaspases (MCAs) are distant evolutionary forms of metazoan caspases found in protozoa, plants and fungi, and seen as potential targets to destroy the parasites without damage to the host. Ligands and modulators of metacaspases are so far unknown. Phage Display is a technique based on the expression of synthetic proteins in the phage capsid, and is used for selecting ligands of proteins, cells or tissues. We have produced the recombinant metacaspase of Leishmania (L.) amazonensis and employed Phage Display to find peptide ligands of this enzyme. These peptides led to the identification of potential binding proteins of the MCA, such as kinases and kinesin, which provide information about the regulation and control of MCA´s activity. In the future we will test whether peptide activators of MCA nduce apoptosis of the parasite and can be used as drugs for the treatment of leishmaniasis.

The present study demonstrates that blue grouse on Vancouver Island are infected with two species of Haemoproteus, probably two species of Leucocytozoon and a species of Trypanosoma. Haemoproteus dendragapi n.sp. is described from the Nanaimo Lakes Area. The growth rate of H. canachites gametocytes is much more rapid than that described by Fallis in Ontario. The very young tissue stages of H. canachites are described from lung preparations of grouse chicks. The life cycle of Leucocytozoon bonasae has been completed by using a new vector, Cnephia minus. As reported by Fallis in Ontario, Simulium aureum has been found to be a vector of L. bonasae on Vancouver Island. This study has verified Woodcock's often ignored hypothesis that the morphology of the gametocyte-host cell complex changes with age of infection. A probable new species of Leucocytozoon is described from the Campbell River Area. In-vitro culture of the trypanosome from grouse blood has been carried out. A yearling blue grouse has been successfully infected by inoculation of metacyclic trypansomes from the culture. / Science, Faculty of / Zoology, Department of / Graduate

Durante o ciclo de vida da Leishmania, amastigotas vivem no interior de fagolisossomas de células fagocíticas de hospedeiros vertebrados, enquanto promastigotas vivem no interior do vetor invertebrado. Proteases intracelulares como as caspases são as principais efetoras no processo apoptótico. Metacaspases (MCAs) são formas evolutivas distantes das caspases de metazoários, presentes em protozoários, plantas e fungos, e vistas como potenciais alvos para combate dos parasitas sem prejuízo do hospedeiro. Ligantes e moduladores das metacaspases são até hoje desconhecidos. O Phage Display é uma técnica baseada na expressão de proteínas sintéticas nos capsidíos de fagos, usada com o propósito de selecionar ligantes de proteínas, células ou tecidos. Produzimos a metacaspase recombinante de Leishmania L. amazonensis e aplicamos Phage Display para buscar peptídeos ligantes dessa enzima. Esses peptídeos permitiram identificar potenciais proteínas ligantes da MCA, como quinases e cinesinas, que fornecem informações sobre a regulação e controle de sua atividade. Futuramente testaremos se peptídeos ativadores da MCA poderão induzir apoptose do parasita e serem usados como drogas para o tratamento da leishmaniose. / During its life cycle, Leishmania amastigotes live inside phagolysosomes of phagocytic cells of vertebrate hosts, while promastigotes live inside the invertebrate vector. Intracellular proteases such as caspases are key effectors in the apoptotic process. Metacaspases (MCAs) are distant evolutionary forms of metazoan caspases found in protozoa, plants and fungi, and seen as potential targets to destroy the parasites without damage to the host. Ligands and modulators of metacaspases are so far unknown. Phage Display is a technique based on the expression of synthetic proteins in the phage capsid, and is used for selecting ligands of proteins, cells or tissues. We have produced the recombinant metacaspase of Leishmania (L.) amazonensis and employed Phage Display to find peptide ligands of this enzyme. These peptides led to the identification of potential binding proteins of the MCA, such as kinases and kinesin, which provide information about the regulation and control of MCA´s activity. In the future we will test whether peptide activators of MCA nduce apoptosis of the parasite and can be used as drugs for the treatment of leishmaniasis.

The purpose of this research was to examine the colonization process and relationship of physico-chemical parameters to diatom and protozoan communities colonizing polyurethane foam (PF) artificial substrates in lentic habitats. This was the first study to utilize multivariate techniques for comparison of protozoan and diatom communities The following hypotheses were examined in this study: 1. diatom and protozoan species accrual is similar because the organisms are approximately the same size and share similar ecological conditions, 2. protozoan assemblages are influenced by the physicochemical parameters of their environment, and 3. diatoms and photosynthetic protozoans are more closely related to the physico-chemical parameters of their environment than are the protozoans of all trophic groups. PF substrates were placed in the littoral zone of lentic habitats. Substrates were sampled through a time series and examined for their diatom and protozoan species' presence-absences. The first hypothesis was tested by using the MacArthur-Wilson equilibrium model and by fitting the data to the model by non·linear least squares regression. Protozoan species accrual fit the model in most cases, while diatom species accrual did not. The second part of the research dealt with five lentic habitats in northern lower Michigan which were sampled as described above and concurrent with organismal sampling several physico-chemical parameters were sampled. These environmental parameters included pH, alkalinity, conductivity, temperature, and concentrations of dissolved oxygen, chloride, silica, ammonia, and total and ortho-phosphate. Protozoan communities were examined using reciprocal averaging ordination. It was found that the bog and marsh had distinct communities, while the three lakes did not. Several physicochemical parameters and factors correlated significantly with axes generated by samples in species space. The final section tested the degree of relationship among diatoms, autotrophic protozoans, and protozoans to the physicochemical parameters and factors. pH had the highest correlations with the first axes for each group. Diatom communities had the greatest degree of relationship to the physico-chemical parameters, evidence for this is provided by the greatest number of correlations between ordination axes and the physico-chemical parameters and factors. / Ph. D. / incomplete_metadata