Parasitology Commons^™

The Role Of Unrealistic Optimism In Explaining Preventive Behaviors In High Versus Low Endemic Malaria Settings In Belize, Daniel G. Handysides

Loma Linda University Electronic Theses, Dissertations & Projects

Background: Of all the diseases an individual can encounter in the world, malaria is one of the most destructive. Simple measures like sleeping under a bednet would greatly reduce the burden (Abeku, 2007). When people estimate their risk relative to others, they are most often unrealistically optimistic, which may explain why those at risk often fail to perform behaviors, such as using a bednet that will reduce their risk. However, one study showed that people at high risk for malaria held pessimistic perceptions of their risk for the disease, but the reasons for this finding are unclear (Morrison, Ager, & …

Effects Of Corticosteroids And Of Cyclosporin A On Trypanosoma Musculi In Mice And In Culture, Philip Stephen Schuyler

Loma Linda University Electronic Theses, Dissertations & Projects

The in vivo and in vitro effects of cyclosporin A and corticosteroids on Trypanosoma musculi were examined. Mice that received continuous administration of 6 mg/liter/day of dexamethasone in drinking water and 200 mg/kg hydrocortisone acetate as a single dose 24 hrs prior to injection with T. musculi had significantly higher and longer parasitemias, than controls. Body and spleen weights and B cell responsiveness were lower in test animals and there were some deaths. Mice injected with T. musculi that received 100 mg/kg/day cyclosporin A had longer, but not higher, parasitemias than controls. Corticosteroids appear to partially inactive antibody production (i.e. …

A Rapid Concentration And Identification Technique For Human Malaria Infections Using A Mouse Model, Donald D. Barton

Loma Linda University Electronic Theses, Dissertations & Projects

Red blood cells infected with malaria parasites experience a change in density making them lighter (less dense). This paper reports a new, rapid diagnostic technique using this change in density in the infected red blood cell. It is not only easy to use, but it is also compatible with the technological conditions found where the malaria problem is most acute - in many developing countries of the world. A small sample of blood drawn from a simple finger stick can be concentrated and examined microscopically for malaria parasites within 10 minutes. The thick film slide preparation, presently used, takes a …

Cryptosporidiosis In The Immunosuppressed Mouse And In Cell Culture, Mercy Prabhu Das

Loma Linda University Electronic Theses, Dissertations & Projects

Cryptosporidiosis is a parasitic infection primarily of animals that has been recently recognized as an important disease in immunocompromised humans. Most cases to date have occurred in patients with acquired immunodeficiency syndrome (AIDS). Persons with abnormal humoral or cellular immune function, and even normal subjects, have also been affected.

To determine whether or not mice, when experimentally immunosuppressed, would develop cryptosporidiosis, a test was designed using the AKR/J strain. This strain was selected because, it was previously reported that it was the strain shown to respond most readily to the production of disease caused by the opportunistic protozoan, Pneumocystis carinii …

The Effects Of Temperature And Ph On The Differentiation Of Trypanosoma Lewisi (Kent, 1880) Laveran & Mesnil, 1901, In A Defined Medium, Carolann R. Rosario

Loma Linda University Electronic Theses, Dissertations & Projects

Trypanosoma lewisi is an arthropod-transmitted protozoan parasite found in the bloodstream of rats. In its life cycle it undergoes cellular differentiation. It is primarily found as the trypomastigote form in the rat and as the epimastigote form in the arthropod, the rat flea. Various studies have been done on hemoflagellates to determine the factors responsible for stimulating the differentiation from one form to the other. Included in these factors are pH, temperature, and protein fractions from fetal calf serum. Recent efforts have also been aimed at developing simple or defined media for physiological or biochemical studies on hemoflagellates. The purpose …

Concomitant Infections With The Parasites Trypanosoma Musculi Kendall, 1906 And Trichinella Spiralis (Owen, 1835) Raillet, 1896 In The Laboratory Mouse, Musmusculus, Joan Chew Liang Tan

Loma Linda University Electronic Theses, Dissertations & Projects

Four groups of female Swiss Webster mice were injected intraperitoneally with similar volumes of normal saline, sonicated Trypanosoma musculi and saline, sonicated trypanosomes and Freund's Complete Adjuvant (FCA) and FCA. When the mice became immune and thus responded negatively to a T. musculi challenge, sera were collected and administered to four other groups of mice to establish passive immunity in these animals.

An established dose of innoculum of Trichinella spiralis larvae (8.1 larvae/gram of body weight) was given to all the mice by gastric gavage. These mice were killed 26 days later and the musculature digested with artificial gastric juice …

Effects Of Trypanosoma Musculi Kendall, 1906 Immune Serum On The Reproduction Of Trichinella Spiralis (Owen, 1835) Railliet, 1896 In Mice, Samuel L. Chafin

Loma Linda University Electronic Theses, Dissertations & Projects

The possible effects of ablastin, a reproduction-inhibiting antibody which is produced during the infection of the blood parasite, Trypanosoma musculi in the mouse, were investigated by fractionating the parasite into a supernatant fraction (designated as Group A test mice) and a pellet fraction (Group B test mice). These groups A and B mice were injected with the respective fractions, plus Freund’s Complete Adjuvant (FCA). Control mice were injected with FCA only. Sera from these three groups of mice were removed after the Group A and Group B mice were shown to be negative to T. musculi challenge, and Group A …

Concurrent Infection Of Trypanosoma Musculi Kendell, 1906, And Schistosoma Mansoni Sambon, 1907 In Mice, Berhane Andeberhan

Loma Linda University Electronic Theses, Dissertations & Projects

The possible effects of ablastin on Schistosoma mansoni were investigated by (1) establishing a concurrent infection of Trypanosoma musculi and Schistosoma mansoni in mice, and (2) by obtaining Trypanosoma lewisi immune rat serum (ablastin) and injecting it into S. mansoni infected mice. These procedures were followed on days 4, 14 and 28 of S. mansoni infection. For the groups that were given immune rat serum, controls were kept into which normal rat serum was injected.

Ablastin does not have any effect on the development or morphology of the S. mansoni worms as tested in this study. Although ablastin inhibits glycolytic …

Concurrent Infections Of Trypanosoma Equiperdum And Trichinella Spiralis In Mice, Pauline A. Nembhard

Loma Linda University Electronic Theses, Dissertations & Projects

In concurrent infections of Trichinella spiralis and Trypanosoma equiperdum, the survival times vary in the early stages of the Trichinella infection. On Days 1 and 4, the mean survival times are significantly increased, and on Days 3 and 7 they are markedly decreased. This decrease is probably due to intestinal tissue invasion. Mice infected with trypanosomes after the 7th day of the Trichinella infection have survival time increases to a significant point and a steady leveling off to Day 21. It is suggested that the antibodies produced against the Trichinella worms slow down multiplication of trypanosomes and increase the …

The Comparative Histochemistry Of The Infective Oncospheres Of Oochoristica Osheroffi Meggitt, 1934, And Oochoristica Scelopori Voge And Fox, 1950, (Cyclophyllidea: Linstowiidae) With Notes On The Origins Of The Egg Membranes, Gary R. Coulter

Loma Linda University Electronic Theses, Dissertations & Projects

Infective oncospheres of Oochorlstica osheroffi and Oochoristica scelopori were compared using fifteen histochemical tests. Vital stains were also used.

Carnoy’s-fixed gravid proglottids were vacuum-embedded in a paraffin-piccolyte mixture and cut transversely at 6 microns. Sections were tested for the presence of phosphatases, proteins, sclerotin precursors, nucleic acids, carbohydrates and acid mucopolysaccharides.

Oncospheres were histochemlcally very similar. Heavy concentrations of mucoproteins and glycoproteins were detected in the oncospheral coat of O. scelopori. Acid phosphatase was found in the embryophore of O. osheroffi, but could not be demonstrated in O. scelopori. No evidence of a sclerotized egg capsule was …

Infectivity And Development Of Trichinella Spiralis In Germ-Free, Monocontaminated And Conventional Mice, Daulat Sitanggang

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of the experiment was to compare the development of Trichinella spiralis in germ-free, Lactobacillus casei monocontaminated, Escherichia coli monocontaminated and conventional mice. The criteria used in the experiments were the recovery of adults and larvae of T. spiralis after 72 hours and one month post-infection, respectively. which gave an indication of the effects of no bacteria or only a certain, single species of bacterium on the development of this nematode in mice.

Germ-free T. spiralis larvae were obtained by washing them several times with sterile normal saline, and treatment with antibiotics. The gavaging procedure was done without anesthetization …

Some Aspects Of Carbohydrate Metabolism In The Cercariae Of Schistosoma Mansoni Sambon, 1907, A. Eugene Dunham Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

Cercariac of Schistosoma mansoni were studied for glycogen utilization, uptake of glucose from solution, lactic acid production, and respiration.

Using the anthrone method of determination of carbohydrate, the amount of glycogen used by a single cercaria in 4 hours is determined as 43.2 x 10^-4 μg ± 6.6 x 10^-4 μg.

Glucose was not observed to have been used from solution under the conditions of the experiment, even in the presence of trehalose. The determinations were made by the Glucostat method.

After deproteinization and desugarization, aliquots of supernatant from cercarial suspensions were analyzed for lactic acid using p-phenylphenol …

Concurrent Infections Of Schistosoma Mansoni And Trypanosoma Equiperdum In Mice, Venus Ee-Siriporn

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this investigation was to determine factors which may influence the survival time of mice infected with Trypanosoma equiperdum and the effects of T. equiperdum on mice infected with Schistosoma mansoni.

In order to maintain experimentally obtained standard hours of survival (88 hrs) in mice inoculated intraperitoneally with 150,000 T. equiperdum, it was found that trypanosomes removed from the donor rat should be kept at 25 C and all counts, dilutions of the organisms, and injection should be completed within 1 hour after removal from the donor host. Survival time of mice is increased as the …

Carbon Dioxide Fixation In Schistosoma Mansoni, Clint Earl Carter

Loma Linda University Electronic Theses, Dissertations & Projects

Adults of the blood fluke Schistosoma mansoni were perfused from the hepatic portal system of CF1 female mice sixty to seventy days post infection. The worms were then incubated in Eagle’s minimal essential medium with glutamate and 0.03 mg/100 ml of nonlabelled aspartic acid. To this medium was added 10 μc of either NaH¹⁴0₃, glucose-UC¹⁴ or aspartate-4-C¹⁴. The worms were found to fix carbon from the NaH¹⁴0₃ and to incorporate the glucose and aspartate. The amount of activity recovered in five different chemical fractions after two hours incubation was determined …

The Effect Of Schistosoma Mansoni On Free Amino Acid Levels In Mice, Richard D. Tkachuck

Loma Linda University Electronic Theses, Dissertations & Projects

Free amino acid levels in the blood plasma of mice infected with Schistosoma mansoni Sambon, 1907, were measured at 3, 6, and 9 weeks post-infection with an automatic amino acid analyzer. Significant differences between experimental and control animals occurred at all three time periods. At 3 weeks, asparagine, alanine, citrulline, proline, methionine, and threonine levels all were lower in the infected animals. At 6 weeks, four differences were noted. Alpha-amino-n-butyric acid, ornithine, lysine, and histidine all had lower values in infected animals. At 9 weeks there were 12 differences. Tyrosine, phenylalanine, threonine, serine, proline, citrulline, glycine, alanine, valine, isoleucine, and …

The Effect Of Varying Protein Intake On Trichinella Spiralis Infection In Mice, Clare K. Kwan

Loma Linda University Electronic Theses, Dissertations & Projects

Three hundred Swiss Webster albino mice three weeks of age were placed on low (8%), medium (24%), high (48%) protein levels and a commercial laboratory animal feed, Purina Chow for various lengths of time: (1) simultaneously with infection, and four weeks thereafter, (2) three weeks before infection and throughout the four-week infection period, and (3) six weeks prior to infection and during the infection period. The protein source was casein. Sixty of the 300 mice used served as noninfected controls, and the other 240 were each infected with 400 washed, suspended Trichinella spiralis larvae obtained from a rat by the …

Life History Of A Haemogregarine, Hepatozoon Sp. In The Chuckwalla: Sauromalus, John E. Lewis

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Natural History Of Thelazia Californiensis Price, 1930 (Nematoda: Thelaziidae), A Mammalian Eye Worm, Warren E. Parmelee

Loma Linda University Electronic Theses, Dissertations & Projects

Various factors—embryology, host associations, and seasonal changes In eye worn populations—tending to promote the propagation of T. califomlensls were studied.

The early embryology closely parallels that of other nematode species.

The mature embryos remain alive in saline at 35°C as long as 5 days. Dead embryos can be distinguished from living ones by virtue of the rapid staining by methylene blue by the former. Parturient female thelazias release embryos into saline, and embryos are found regularly in tear secretions of infected laboratory rabbits.

Ovic embryos possess an enveloping egg membrane containing chitin. On this account, this eye worm species is …

Natural And Experimental Infections Of Thelazia Californiensis Price (1930, Nematoda: Thelaziidae) With Descriptions Of The Adult And Larval Parasites, Howard S. Burnett

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this work was to determine the extent and effects of infestation of the eye worm of mammals, Thelazia californiensis, and to elucidate through experimentation or observation the mode of transmission.

A survey of literature revealed that thelaziasie (infestation by Thelazia species) may cause serious pathological changes in the eye and its adnexa, sometimes resulting in blindness. It was found that reports of thelaziasis in the United States were (with two exceptions) of cases in California. It was further found that T. californiensis has been reported in a wider variety of host than has any of other …