Faculty of Health Sciences
School of Medicine
Department of Anatomy
Selected Highlights from Research Findings
Traditional herbal remedies have been used for many generations in various cultures to treat a broad spectrum of ailments. Examples include wild cannabis (Leonotus leonorus,) Euphorbia hirta, Withania somnifera and Urginea sanguinea, which are frequently used by herbalists in Southern Africa to treat asthma.
Little is known about the physiological consequences of using such herbal remedies – although there is reason to believe that some of them might have deleterious effects that far outweigh their benefits.
One piece of evidence supporting this assertion is the fact that Urginea sanguinea, in addition to alleviating asthmatic symptoms, is also sometimes used to induce an abortion. A substance capable of causing such a severe reaction in the body is likely to possess a high level of cytotoxicity.
Under the leadership of Prof Resia Pretorius, the Section of Histology and Cell Biology within the Department of Anatomy has conducted extensive research on the effects of traditional herbal asthmatic remedies on cellular structures.
The specific focus of their research – which is funded primarily by the NRF and has produced 89 publications since 2000 – is the impact of such remedies on the coagulation system and the nervous system.
The spectrum of methods employed in this research includes animal experiments. In a recent study, for instance, Pretorius and her team investigated the effects of the above-mentioned plants on brain development in growing chick embryos.
In 2006, the group successfully established a Balb/c mouse asthmatic model at the Onderstepoort animal facilities. Euphorbia hirta was tested successfully using this model. The relevance of these specially bred mice for their research resides in the fact that they can be made to display asthmatic symptoms through exposure to an allergen.
They therefore represent a living laboratory for investigating the effects of various anti-asthmatic substances. The research group also makes use of permanent and primary cell cultures, which allow them to study morphological changes in cells after exposure to a medicinal substance.
In addition to broadening scientific knowledge regarding the cellular effects of plant-based medicines, the group’s research also offers tangible benefits for communities. In particular, it is aimed at raising awareness about the possible dangers of some traditional remedies and promoting the use of herbal medicines that do not have such cytotoxic properties.
Contact person: Prof E Pretorius.
A number of projects have been conducted by members of the Physical Anthropology research group of the Department of Anatomy that help to unravel mysteries of the distant and recent past.
The Mapungubwe gold graves revisited
The discovery of the hilltop burial site at Mupungubwe in the Limpopo valley represents one of the most spectacular archaeological finds ever made in South Africa. First excavated in the 1930s, the site contains a number of graves that are thought to be the final resting place of the rulers of an ancient African trade kingdom.
The high status of the individuals buried in these graves is revealed by the fact that at least three of the graves contained a wealth of golden artefacts. Unfortunately, very little information is available today on the condition of the graves when they were first excavated.
This may be ascribed to a combination of factors, including the circumstances under which excavations were made. In order to unravel some of the site’s mysteries, researchers in the Physical Anthropology research group fine-combed the remaining information relating to the three gold burials.
On the basis of archival reports and previously unpublished photographs, they were able to piece together a body of evidence suggesting that at least one of the burials – the so-called “Gold Grave” – may in fact have been a secondary burial, similar to that of a male burial at Thulamela – a stone citadel in the northern part of the Kruger National Park.
Key pieces of evidence supporting this argument include the arrangement of the bones and the positioning of the gold objects found with the grave
In sickness or in health?
Toutswe is located about 200 kilometres to the west of Mapungubwe, in east central Botswana. During the Early Iron Age (AD 700 to AD 1300), this area was inhabited by mixed farmers.
Previous research – in particular, the results of palaeodemographic analysis – suggest that the Toutswe people were better off than the contemporary inhabitants of Mapungubwe, as well as those of K2 (a neighbouring site).
MSc student M Mosothwane has studied the bones and teeth of 84 individuals from ten sites at Toutswe. The study was aimed at garnering independent evidence pertaining to the general health of the Toutswe communities – a task that had not been attempted before.
The individuals whose remains were analysed during the study ranged from newborn to 75 years of age, and included both sexes. Their teeth and bones were analysed for osteological manifestations of diseases.
This analysis revealed the presence of diseases commonly found in archaeological populations, such as osteoathritis, spina bifida occulta, cribra orbitalia, porotic hyperostosis and enamel hypoplasias.
One possible case of diffuse idiopathic skeletal hyperostosis (a form of degenerative arthritis characterised by excessive bone growth along the sides of the vertebrae) was also found.
The frequency of lesions was found to be comparable or even lower than at other, similar sites (which include K2, Mapungubwe and sites elsewhere in southern Africa). These findings suggest that the people of Toutwse did indeed live in fairly benign circumstances: they had relatively low levels of stress, and were not subjected to unduly high rates of infection.
Although members of the Physical Anthropology research group concentrate much of their efforts on elucidating the distant past, their research is also often concerned with matters closer to the present. As the following paragraphs show, forensic investigations form an important part of such research.
Ante-mortem stature estimates in South Africans
Many people find it difficult to judge the height of another in metric terms, even if that person is well known to them. This presents an obstacle in cases where the remains of an unidentified individual have to be linked to a description of a missing person.
Although it is possible to estimate ante-mortem stature of an individual with reasonable accuracy through analysis of his or her skeletal remains, relatives of the missing person might not be able to describe that person’s height with any greater accuracy than to say the person was “tall,” “short” or “of medium height”.
Prof Maryna Steyn of the Department of Anatomy and Jan Ryno Smith of Ergonomics Technologies conducted a study aimed at linking such informal estimates of height to precise measurements.
They compiled a dataset containing the statures of 2 052 Black, 483 Coloured and 880 White South Africans of both sexes, based on measurements that had been taken over a number of years. This dataset enabled them to determine the sex-specific distribution of statures for each population group.
With such a distribution in hand, it is a simple matter to determine the average height of each group, as well as the variability among individuals belonging to that group. It is also possible to determine how tall a person must be to fall in the tallest or shortest 25% of the population comprising that group.
On the basis of these findings, the researchers proposed a simple scheme for interpreting estimates of stature contained in forensic reports: they suggest that the upper 25% of the distribution of each group be regarded as “tall,” the lower 25% as “short” and the middle 50% as “medium.”
A comparison between the results of this study and previous reports on stature among South Africans yielded another interesting finding: there appears to be a weak positive secular trend – meaning that South Africans are gradually getting taller. The study did not attempt to identify the causes of this trend, but it may be related to improvements in nutrition
Contact person: Prof M Steyn.
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