Thesis (Ph. D.)--University of Hong Kong, 1993.

Thesis (M.S.)--University of Akron, Dept. of Biology, 2009. / "August, 2009." Title from electronic thesis title page (viewed 10/7/2009). Advisor, Amy Milsted; Committee members, Monte Turner, Richard Londraville; Department Chair, Monte Turner; Dean of the College, Chand Midha; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

The aim of this thesis was to evaluate the effect of increased intake of selenium from the diet of rats with spontaneous hypertension (SHR) on other essential elements. The effect of different diets on the element levels in kidney, liver, testes, and blood of rats was observed under model conditions. Tested rats were divided into five groups, where the first group A was the reference group and feed mixture contained no additive. In groups B and C was soybean meal replaced by defatted rapeseed and into feed mixture of group C was additionally added vitamin E. Diet groups D and E contained added selenium and zinc, and group E contained additionally vitamin E in comparison to reference group A. Se content in kidney, liver, testicles, and blood of animals was determined by inductively coupled plasma mass spectrometry (ICP MS). The other essential elements (Cu, Fe, Mn, P, S, and Zn) were determined by inductively coupled plasma optical emission spectrometry (ICP OES). The content of Ca, K and Mg was determined by atomic absorption spectrometry with flame atomizer (F-AAS). The hypothesis has been that the increased intake of selenium should improve the use of other essential elements by the rat organism. It was expected that there will be influenced elements mainly involved in the defense of the organism against oxidative stress. This was not confirmed by this experiment. Changes in the concentrations of these elements occurred only at very high dose of selenium that is already toxic to the organism. This toxic effect could be also responsible for fifty percent mortality of rats in group E, where perhaps even increased concentration of vitamin E could not sufficiently reduce the toxicity of high doses of selenium.

Thesis (M.Sc. Biological Sciences)--University of Waikato, 2007. / Title from PDF cover (viewed February 21, 2008) Includes bibliographical references (p. 79-85)

La leptospirose est une zoonose ré-émergente de distribution mondiale, causée par un spirochète du genre Leptospira. L'OMS rapporte environ un million de cas sévères de leptospirose humaine par an à travers le monde, avec un taux de mortalité de 10 %. Les rongeurs étant considérés comme les principaux hôtes réservoirs de cette bactérie, la transmettent aux Hommes et aux animaux, par un contact direct ou indirect via de l'urine infectée. Le rat brun (Rattus norvegicus) est important d'un point de vue épidémiologique car il est réservoir du principal sérogroupe incriminé dans les cas de leptospirose humaine : le sérogroupe Icterohaemorrhagiae. Chez ce rongeur, l'infection est asymptomatique et a été caractérisée par des modèles expérimentaux centrés sur la colonisation rénale des leptospires faisant appel à une voie d'inoculation éloignée des conditions naturelles. De plus, les détails sur la dynamique de transmission rat-rat restent encore inconnus. Il est donc important de mieux comprendre le rôle du rat dans le maintien des leptospires dans l'environnement, afin de mieux contrôler les épidémies de leptospirose humaine et animale. À partir d'un modèle expérimental avec une voie d'inoculation mimant des conditions naturelles (conjonctivale ou sous-cutanée), nous avons mis en évidence que la réponse sérologique semblerait être indépendante de la mise en place de la colonisation rénale, et que la voie conjonctivale serait plus efficace pour devenir porteur rénal que la voie sous-cutanée. De plus, une étude de l'infection naturelle sur le terrain avec les mêmes méthodes d'analyse, a permis de mettre en évidence la présence de leptospires dans les poumons de manière concomitante à un portage rénal chez le même individu. Grâce à la mise au point d'une nouvelle méthode de typage moléculaire, nous avons identifié les souches circulantes de leptospires dans une population urbaine de rats et leur dynamique de transmission. Toutes les souches portées par les rats appartenaient au sérogroupe Icterohaemorrhagiae et chaque colonie de rat ne semblait maintenir qu'une seule souche de leptospires dans sa population / The leptospirosis is a zoonosis caused by spirochetes of the genus Leptospira, which could infect human and animals. This infection represents a major problem of public health in several countries. The WHO estimates at one million of severe cases of human leptospirosis by year in the world, with a 10 % fatality rate. In the human, the leptospirosis is a mortal infection if it is not treated. The rodents, including the brown rat (Rattus norvegicus), are considered as a carrier and excrete pathogenic leptospires via urine, which becomes the main source of direct or indirect contamination of human and animal. In the rat, the asymptomatic infection was few characterized by experimental model, or only focused on the renal colonization using a no-natural inoculation route. Furthermore, the details of the transmission rat-rat remain still unknown. It is important to know the role of the rat in the persistence of leptospires in rural or urban environments, in order to better control leptospirosis epidemics. With an experimental model using conjunctival and subcutaneous routes, we showed that the antibodies production was independent of the rate of renal colonization and that the conjunctival route was more efficient to become renal carrier than the subcutaneous route. Furthermore, a study of the characteristics of natural infection using the same methods showed the presence of leptospires in lung of rat which are renal carriers. With a new method of molecular typing, we have studied the circulating of the Leptospira strains in the rat’s urban population. All the strains belonged to the Icterohaemorrhagiae serogroup and every colony of rats maintained only one strain of Leptospira. The characterization of the infection with the experimental and field studies, and the epidemiological studies are also important to model the infection in the brown rat, for the prevention of human and animal leptospirosis

This study examined the effect of prolonged differential housing and/or diet following exposure to chronic restraint stress on body weight, body fat weight, body fat composition and corticosterone, glucose, insulin and leptin levels. To this end, male Wistar rats were individually-housed (IH) or pair-housed (PH) and fed a condensed milk diet (CD) or a mushy rat chow diet (MD) for twelve weeks. Subsequently, all rats underwent chronic restraint stress (CRS) for seven hours/day for four weeks. During CRS, only PH rats fed MD continued to gain weight, while growth of the other groups was stunted. Housing and diet impacted on body fat weights, where PH caused increased retrorenal fat (P<0.001) in rats fed MD, while in rats fed CD, PH gave rise to less visceral (P<0.01) and more interscapular (P<0.05) and retrorenal fat (P<0.001). The CD resulted in more retrorenal (P<0.001) and interscapular fat (P<0.05) in PH rats, with more visceral (P<0.001) and retrorenal fat (P<0.01) in IH rats. Housing influenced only the fatty acid profiles of the liver and subcutaneous fat in rats fed CD. The CD caused differing fatty acid profiles of the liver, subcutaneous fat, visceral fat, interscapular fat and muscle in PH rats, while altering the fatty acid profiles of the liver, subcutaneous fat, interscapular fat and muscle in IH rats. Housing and diet did not result in differences in corticosterone, insulin and glucose concentrations, while both resulted in significantly elevated leptin levels in PH rats fed CD. Therefore the types of housing and diet have various effects on body weight and glucose and fat metabolism following chronic stress. This dissertation is dedicated to My dear parents, Jeff and Avril Ackerman, for their on-going support My loving husband, Brandon, for his encouragement, assistance and patience My children, Elazar Tzvi, Sara Esther, Yaakov Yehuda and Rossi Bear who have been my stress alleviators and Idah Rangwato and Annah Sibanda who are my right-hand ladies and have made it possible to complete this dissertation- Thank you!

Thesis (Ph. D.)--University of Hawaii at Manoa, 1994. / Includes bibliographical references (leaves 147-160). / Microfiche. / xvii, 160 leaves, bound ill. 29 cm

Thesis (M.Sc.)--York University, 2008. Graduate Programme in Higher Education. / Typescript. Includes bibliographical references (leaves 91-96). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR38784

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Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2018-01-26T12:38:56Z No. of bitstreams: 1 2010 - Juberlan Silva Garcia.pdf: 6866273 bytes, checksum: 77b115c7b87deb998b7440f5ecb87940 (MD5) / Made available in DSpace on 2018-01-26T12:38:56Z (GMT). No. of bitstreams: 1 2010 - Juberlan Silva Garcia.pdf: 6866273 bytes, checksum: 77b115c7b87deb998b7440f5ecb87940 (MD5) Previous issue date: 2010-12-03 / The trematode Echinostoma paraensei parasitizes the small intestine of rodents, being its natural definitive host Nectomys squamipes. In spite of the great importance of echinostomatides, there are few studies on morphology, biology and physiology of E. paraensei and its interaction with their intermediate and definitive hosts. In the present study 50 Rattus norvegicus (Wistar),adult females were used, 35 were individually infected with 150 E. paraensei metacercariae (Sumidouro strain) and 15 were maintained uninfected, as control group. Weekly, seven infected and three uninfected rodents were euthanized using CO2.The blood was collected to hematological analysis, and serum obtained by centrifugation and used to aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma-glutamyl transferase (GGT), bilirubin, glucose, total proteins and fractions determinations. Fragments of liver were collected to glycogen determination and histophatological analysis. Adult worms were loaded until third week of infection, being the higher number of worms loaded at first week of inection. The hepatocytes had rounded edges, with signs of impaired nuclear, mild infiltration of polymorphonuclear and sinusoids slightly expanded. The hepatocytes were vacuolated with discrete perivascular and periportal lymphocytic infiltration. The serum biochemical parameters analyzed were increased at the first week of infection, varying onward. Hematological analysis revealed the development of normocytic and normocromic anaemia with anisocytic alteration. In the white blood cells, only a leukopenia was observed at the third week of infection. The present results are discussed. / O tremat?deo Echinostoma paraensei ? um parasito de intestino delgado de roedores, sendo seu hospedeiro definitivo natural Nectomys squamipes. No presente estudo, foram utilizadas 50 f?meas adultas de Rattus norvegicus (Wistar), 35 animais infectados individualmente com 150 metacerc?rias de E. paraensei (linhagem Sumidouro) e 15 animais n?o infectados (controle). Semanalmente, sete animais infectados e tr?s animais controle foram submetidos ? eutan?sia com CO2. O sangue foi coletado para an?lise hematol?gica, e o soro obtido por centrifuga??o, para as determina??es de aspartato aminotransferase (AST), alanina aminotransferase (ALT), gamaglutamiltransferase (GGT), fosfatase alcalina (ALKP), bilirrubina, glicose, prote?nas totais e fra??es. Fragmentos de f?gado foram coletados para a determina??o de glicog?nio e para a an?lise histopatol?gica. Vermes adultos foram recuperados at? a terceira semana de infec??o, sendo o maior n?mro de vermes recuperados na primeira semana. Os hepat?citos apresentavam-se com bordos arredondados e alguns sinais de comprometimento nuclear, infiltra??o por polimorfonucleares nos sinus?ides, vacuoliza??o, discreta infiltra??o linfoplasmocit?ria perivascular e periportal com poucas c?lulas mononucleares presentes na luz do ducto biliar, alguns hepat?citos estavam hipotrofiados. As an?lises hematol?gicas revelaram o desenvolvimento de uma anemia normoc?tica normocr?mica, com anisocitose. N?o foram observadas altera??es significativas na s?rie branca, havendo apenas uma leucopenia na terceira semana de infec??o. Os resultados obtidos s?o discutidos.