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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A cephalometric study of vervet monkeys with induced hypothyroidism.

Preston, Charles Brian January 1974 (has links)
Dissertation submitted to the Faculty of Dentistry, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Dentistry. / Growth and development of the skull is influenced by metabolic factors such as the endocrinopathies. The purpose of this study is to examine the effects of induced hypothyroidism on growth and development of the skull of the Vervet monkey. Seven infant monkeys of the subspecies Ceraop-ithecus aethiops cloetei were selected as the experimental animals in this study. Two of the seven monkeys were used as the control group, the remaining five monkeys were given radio-active iodine to depress their thyroid activity. Cephalometric records were taken of the animals for a period of approximately one year, at the end of which time they were sacrificed. At the age of 15 months the radiographs of the hypothyroidic monkeys, when compared to those of the control group, exhibit marked differences in cranial form. However, the most marked changes are seen in the cranial vaults of the experimental animals. Some of the findings are examined in the light of a number of theories which have been proposed for the control of the growth and development of the skull. / WHSLYP2017
2

The transitional dentition of cercopithecus aethiops with special reference to the mandibular anterior teeth.

Gavronsky, Gerald January 1980 (has links)
A dissertation submitted in partial fulfilment of the requirements for the degree of Master of Dentistry of the University of the Witwatersrand, Johannesburg. / This dissertation studies the development of the anterior successional teeth prior to eruption, their eruption paths and position of emergence of these teeth in Cercopithecus aethiops, the vervet monkey. The eruption of the permanent dentition is divided into four stages, equivalent to four chapters, with a fifth chapter devoted to an analysis of the pattern or sequence of eruption. This pattern is compared to those of other workers and possible reasons for tooth sequence polymorphism are discussed. Twenty three skulls, fourteen female and nine male are examined and a representative sample chosen from each phase of dental development for dissection. Photographs of each stage are presented, accompanied by a descriptive text but no measurements are recorded. This is a visual and descriptive presentation which 'opens the window' to those aspects of the Cercopithecoid dentition which are not as readily observable by other methods such as clinical examination or radiography. / WHSLYP2017
3

The viruses of vervet monkeys and of baboons in South Africa

Malherbe, H. H. January 1974 (has links)
A Thesis Submitted to the Faculty of Medicine University of the Witwatersrand, Johannesburg for the Degree of Doctor of Medicine / In this thesis are presented briefly the results of studies extending over the period 1955 to 1974. The use of vervet monkeys in South Africa for the production and testing of poliomyelitis vaccine made acquaintance with their viruses inevitable; and the subsequent introduction of the baboon as a laboratory animal of major importance also necessitates a knowledge of its viral flora. Since 1934 when Sabin and Wright described the B Virus which was recovered from a fatal human infection contracted as the result of a macaque monkey bite, numerous viral agents have been isolated from monkeys and baboons. In the United States of America, Dr. Robert N. Hull initiated the classification of simian viruses in an SV (for Simian Virus) series according to cytopathic effects as seen in unstained infected tissue cultures. In South Africa, viruses recovered from monkeys and baboons were designated numerically in an SA (for Simian Agent) series on the basis of cytopathic changes seen in stained preparations of infected cells. Integration of these two series is in progress. Simian viruses in South Africa have been recovered mainly through the inoculation of tissue cultures with material obtained by means of throat and rectal swabs, and also through the unmasking of latent agents present in kidney cells prepared as tissue cultures. Some evidence concerning viral activity has been derived from serological tests. In this thesis the classification of simian viruses later proposed by Dr. Hull in 1968 has been adopted. This Ill comprises five categories based on nucleic acid type and strandedness, and on' ether sensitivity. It has not been possible to provide conclusive proof for the inclusion of a number of South African viruses in the categories to which they have been assigned under this scheme, but the available evidence suffices to indicate that representatives of the five main categories occur in South Africa. Some viruses found in this country are recognized as prototype strains in the internationally recognized classification of simian viruses, and one vervet adenovirus has been widely distributed and studied for its oncogenic properties. The herpesvirus SA8 is sufficiently closely related to the dangerous B Virus of macaques to warrant extreme care in the handling of non-human primates. This virus has been recovered from baboons as well as vervet monkeys. It is becoming evident that viruses recovered from one species may eventually be found to be more common in another species. In South Africa much remains to be done in the field of simian virology, and in this thesis are indicated techniques which could be further exploited and expanded to increase our knowledge of this group of potentially dangerous viruses. / IT2017
4

Quantitative analysis of FMRP expression in the vervet monkey brain, and future trends in fragile X research

Koukoui, Sophia Dona. January 2007 (has links)
Fragile X syndrome (FXS) is the leading cause of inherited mental retardation and developmental delay. In the vast majority of cases, this X-linked disorder is due to a CGG expansion in the 5' untranslated region of the fmr-1 gene and the resulting decreased expression of its associated protein, FMRP (Fragile X associated Mental Retardation Protein). FXS is characterized by a number of cognitive, behavioural, anatomical, and biological abnormalities. This monogenic disorder provides a unique opportunity to study the consequence of a mutation in a single gene on the development and proper functioning of the CNS. / Histological work on FMRP expression in the monkey lateral geniculate nucleus (LGN) has revealed differential staining in the magnocellular and parvocellular layers, with increased expression in the magnocellular layers (Kogan, Boutet, Cornish, Zangenehpour, & Mullen, 2004). In individuals with fragile X, this differential expression pattern is correlated at the behavioural level with impairments in the M but not the P-visual pathway processing. These findings by Kogan and colleagues, led to the hypothesis that brain regions that express high levels of FMRP are particularly susceptible to its reduced expression, as occurs in FXS. It was therefore of interest to extend this work to determine the pattern of FMRP expression throughout the monkey brain, with the aim of identifying the brain structures most susceptible to reduced expression of the fmr-1 gene product. / The current focus on the role of FMRP in RNA translation and neuronal maturation makes it timely to assemble the extant information on how reduced expression of the fmr-1 gene leads to neuronal dysmorphology. The first section of this manuscript offers a summary of recent genetic, neuroanatomical, and behavioural studies of fragile X syndrome, and provides potential mechanisms to account for the pleiotropic phenotype of this disorder. The following section presents a detailed account of the FMRP expression profile in the monkey brain, and reveals the striking correlation between the expression of the protein and behavioural deficits associated with its reduced expression, as occurs in FXS. / The last chapter of this manuscript offers insight into future trends in FXS research. A number of electrophysiological and behavioural studies point to a particular involvement of the metabotropic glutamatergic system in FXS, with a preeminent role for metabotropic glutamate receptor type V (mGluR5). The involvement of this receptor in FXS and the potential therapeutic implications of pharmacological regulation of this receptor will be discussed. / There is a body of work pointing to the remarkable behavioural similarities between FXS and autism. While FXS is a single-gene disorder, autism is associated with a number of genes, which have not yet been precisely identified. The final section of this manuscript delineates the neuroanatomical, behavioural, and linguistic overlap, as well as the differences between the two conditions. Finally, this section affords some insight as to how FXS, a single-gene disorder, may assist us in our understanding of autism. / Keywords: Fragile X Syndrome (FXS), fmr-1 mutation, lateral geniculate nucleus (LGN), anterior cingulated cortex (ACC), dentate gyros (DG), superior frontal gyrus (SFG), cerebellum, metabotropic glutamate receptor type V (mGluR5), postsynaptic density protein 95 (PSD-95), dendritic spine, autism / Abbreviations: fragile X syndrome (FXS), long-term potentiation (LTP), long-term depression (LTD), RNA-binding protein (RBP), lateral geniculate nucleus (LGN), anterior cingulated cortex (ACC), dentate gyrus (DG), superior frontal gyrus (SFG), metabotropic glutamate receptor type V (mGluR5), postsynaptic density protein 95 (PSD-95), region of interest (ROI), deep cerebellar nucleus (DCN).
5

Quantitative analysis of FMRP expression in the vervet monkey brain, and future trends in fragile X research

Koukoui, Sophia Dona. January 2007 (has links)
No description available.
6

Skills used in food processing by vervet monkeys, Cecropithecus aethiops

Harrison, Kathryn January 1997 (has links)
The principle objective of this study was to describe and record all the gathering and processing skills of vervet monkeys for a variety of different foods. The study was conducted on two troops of vervet monkeys living in the Palmiet Valley, Natal, South Africa. There was sufficient data to analyze the processing of four foods of differing complexity; termites, leaf shoots, sugarcane and fruit. Milton (1988) proposed that the intellectual difficulties of finding and processing food led to the evolution of intelligence. In the only study of food processing skill, Byrne and Byrne (1993) showed that gorillas use a hierarchical organization perhaps reflecting imitation at the program-level. The question to be asked in this study was, would vervets also organize their processing into a few techniques for specific foods and would it then be possible to identify learning mechanisms used by the monkeys? The current literature suggests that monkeys use simple solutions to their foraging problems, there is no evidence for imitation of feeding skills in monkeys. At the most detailed level of analysis, grip types used in the processing of foods were described. Existing definitions in the literature were not adequate to explain the monkeys' hand use, and new definitions were added. High individual idiosyncrasy was a feature of grip usage across all four foods, although firm conclusions are not possible because of the known effects of sample size. Cluster analysis was considered the most appropriate method to look at individual variation in grip usage. There was an age effect for leaf shoots and sugarcane, with juveniles restricting their usage to the necessary core grips. The hand preferences for individuals across tasks gave no support for the theory of the evolution of laterality presented by MacNeilage et al. (1987). There was a low degree of individual preference for five out of six tasks, with only termite feeding showing a hand preference. There was some evidence for a right hand reaching, left hand manipulation preference, opposite to MacNeilage's prediction. There was an age effect in direction and strength for two tasks, adults having a stronger left hand preference in contrast to a weaker right hand preference in juveniles for leaf shoots and large fruit. Matrices of the transitional probabilities between two elements, were used to construct the common pathways of processing skill for each individual. Flow diagrams were then created to represent the minimal decision processes used by the monkeys. The diagrams were used to compare individuals' choice of pathways. Cluster analysis was used to analyze pathway choice in detail; none of a variety of independent variables could explain the high individual variation. Whether whole foods or just parts of foods were eaten did explain some of the variance for sugarcane and fruit. The most parsimonious explanation is that social enhancement resulting in trial and error learning best described individuals' acquisition of processing skill, although a number of other factors may explain the observed results.
7

Molecular properties of uterine cytosolic and nuclear oestrogen and progesterone receptors of the primate cercopithecus aethiops pygerythrus.

Klien, Tirza January 1985 (has links)
A thesis submitted to the Faculty of Medicine University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. / In the past 25 years, a large volume of data was collected on steroid hormone receptors and their role in the action mechanisms of steroid hormones. Efforts were made to use the principles, derived from fundamental investigations into the actual function of steroid hormone receptors in target tissues, (e.g. breast and uterine tissues) to provide a comprehensive understanding of the nature of hormone responsive tumours (e.g. breast tumours) and to formulate successful endocrine treatment regimes for e.g. breast cancer patients. Although some measure of success was achieved with antihormonal drugs like tamoxifen, clomiphene, medroxyprogesterone acetate, etc. a statistical analysis of patient response data has revealed disappointingly low median response times for breast cancer patients. A number of reasons can be offered in explanation of the discrepancies between theory and practice, however, it was felt that the two most obvious ones are the lack of a proper animal model, closer to man on the species scale, and insufficient understanding of the actual in vivo mechanisms of steroid hormone action. For this very reason it was decided to launch an in depth investigation into the properties and functions of steroid hormone receptors in the biological action of steroid hormones, especially the sex steroid hormone receptors, like the oestrogen and progesterone receptors. Furthermore, it was decided to employ a nonhuman primate, Cercopithecus aethiops pygerythrus, commonly called the Vervet monkey, as the animal model, instead of the more common Sprague-Dawley rat. Since the field of investigation defined is both broad and deep, it is obvious that this thesis could not contain all the answers. So, in view of the obvious limitation in time and man-power, the prime object for this thesis was defined as the laying of sound foundations for future research on the topic specified above. Thus, it was decided to concentrate on the molecular properties of the uterine oestrogen and progesterone receptors of the Vervet monkey. The basic arsenal of biochemical technology used in protein chemistry (competitive protein binding assays, sucrose density gradient analysis, size exclusion chromatography, ion exchange chromatography, chromatofocussing, isoelectric focussing) and available in the Institute of Life Sciences, Faculty of Medicine, University of Pretoria at the time of this investigation, was employed. In view of the information generated in the course of the study, attention was focussed upon a small, but important aspect of the mechanism of steroid hormone action, namely the process of activation or tranformation of receptor- ligand complexes and their interaction with the nuclear compartment. Since disturbance(s) in these processes in abnormal uterine tissues may exist, a limited study of the oestrogen and progesterone receptors in human uterine tissues was undertaken, because no abnormal Vervet monkey uterine tissues were available. Unfortunately it was also extremely difficult to obtain an abundance of pathological human uterine tissues necessary for an adequate study. The investigator consequently had to be content to study only a small number of pathological uterine specimens. Thus the latter part of this thesis only skims the surface of what could have been a major fait accompli with possible clinical significance. / WHSLYP2017
8

The stability of matrilineal dominance hierarchies in vervet monkeys (Cercopithecus aethiops sabaeus) /

Vermeer, Lotus Arrieta January 1993 (has links)
Factors influencing the stability of matrilineal dominance hierarchies were investigated in a feral troop of vervet monkeys (Cercopithecus aethiops sabaeus) in Barbados. Changes in the matrilineal dominance hierarchy were investigated over a 12-year period (1979-1991). Matrilineal ranks remained unchanged for the first 7 years (stable period), reversed on several occasions over the next 3.5 years (unstable period), and have re-stabilised for a further 3.5 years to present date. The frequency distribution of non-matrilineal supports in different social contexts, the lower support frequency in unstable than stable periods, and in particular the high reciprocity evident in non-matrilineal support exchanges, suggest that non-matrilineal support is better explained by reciprocal altruism than by mutualism in vervet monkeys. (Abstract shortened by UMI.)
9

The stability of matrilineal dominance hierarchies in vervet monkeys (Cercopithecus aethiops sabaeus) /

Vermeer, Lotus Arrieta January 1993 (has links)
No description available.
10

Genetic variation between demes of geographically separated African green monkeys

Smith, Sandra January 1991 (has links)
This study investigates the possibility of genetic diversity between geographically separated demes of Cercopithecus aethiops on the islands of St. Kitts and Nevis. The island of St. Kitts was represented by two geographic demes, one from the Northern tip of the island and one from the Southern tip of the island. The island of Nevis was considered as one separate deme. / Eight plasma proteins were analyzed with polyacrylamide gel electrophoresis. A preliminary DNA investigation was also completed. / Three of the plasma proteins--transferrin, albumin, and an unidentified protein that migrated faster than albumin--appeared to be monomorphic. Three proteins in the alpha globulin region (between transferrin and albumin) and pseudocholinesterase were polymorphic in the total population. The DNA locus identified by the Human Molecular Fingerprinting #1 probe (locus D1Z2) was also polymorphic in all demes. / The levels of heterozygosity for North Island, South Island, and Nevis were 2.02%, 2.49%, and 2.49% respectively. / North and South Island demes were more similar to each other than either was to the Nevis deme. The South Island deme was more unlike Nevis than the North Island deme. These figures do not provide sufficient genetic evidence to evaluate divergence within the West Indian vervets according to geography.

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