Patterns of Disease at Selected Rhodesian Hospitals

A CAJM article on disease patterns at selected Zimbabwean hospitals

The age of childbirth in the Bantu of Southern Rhodesia

A CAJM analysis of a survey to determine age of childbirth of native African women of Southern Rhodesia (now Zimbabwe) in 1948.In 1948 a sample census of the African population of Southern Rhodesia was carried out. During this census it was found that most Africans have only a rough idea of their ages, and consequently they were divided into two broad age groups. These groups were (a) up to and including puberty; and (b) over puberty. Puberty was considered to be any age between 12 and 15 years. Another sample census of the African population is being undertaken at the present time. It seemed to be of interest to try and determine the age at which African women were bearing their children, as some idea of the fertility rate might thereby be determined

New lamps for old: the advance to social medicine

An Inaugural lecture given by Professor Ross on the subject of Social Medicine

Computational analysis of nucleosome positioning datasets

Chromatin is a complex of DNA and histone proteins that constitutes the elemental material of eukaryotic chromosomes. The basic repeating sub-unit of chromatin, the nucleosome core particle, is comprised of approximately 146 base pairs (bp) of DNA wrapped around an octamer of core histones. Core particles are joined together by variable lengths of linker DNA to form chains of nucleosomes that are folded into higher-order structures. The specific distribution of nucleosomes along the DNA fibre is known to influence this folding process. Furthermore, on a local level, the positioning of nucleosomes can control access to DNA sequence motifs, and thus plays a fundamental role in regulating gene expression. Despite considerable experimental effort, neither the folding process nor the mechanisms for gene regulation are currently well understood.Monomer extension (ME) is an established in vitro experimental technique which maps the positions adopted by reconstituted core histone octamers on a defined DNA sequence. It provides quantitative positioning information, at high resolution, over long continuous stretches of DNA sequence. This technique has been employed to map several genes: globin genes (8 kbp), the beta-lactoglobulin gene (10 kbp) and various imprinting genes (4 kbp).This study explores and analyses this unique dataset, utilising computational and stochastic techniques, to gain insight into the potential influence of nucleosomal positioning on the structure and function of chromatin. The first section of this thesis expands upon prior analyses, explores general features of the dataset using common bioinformatics tools, and attempts to relate the quantitative positioning information from ME to data from other commonly used competitive reconstitution protocols. Finally, evidence of a correlation between the in vitro ME dataset and in vivo nucleosome positions for the beta-lactoglobulin gene region is presented.The second section presents the development of a novel method for the analysis of ME maps using Monte Carlo simulation methods. The goal was to use the ME datasets to simulate a higher order chromatin fibre, taking advantage of the longrange and quantitative nature of the ME datasets.The Monte Carlo simulations have allowed new insights to be gleaned from the datasets. Analysis of the beta-lactoglobulin positioning map indicates the potential for discrete disruption of nucleosomal organisation, at specific physiological nucleosome densities, over regions found to have unusual chromatin structure in vivo. This suggests a correspondence between the quantitative histone octamer positioning information in vitro and the positioning of nucleosomes in vivo.Further, the simulations demonstrate that histone density-dependent changes in nucleosomal organisation, in both the beta-lactoglobulin and globin positioning maps, often occur in regions involved in gene regulation. This implies that irregular chromatin structures may form over certain biologically significant regions.Taken together, these studies lend weight to the hypothesis that nucleosome positioning information encoded within DNA plays a fundamental role in directing chromatin structure in vivo

Broadening The Horizon: A Glimpse Of General Practice In Rhodesia

A CAJM article on General Practice (GP) in Zimbabwe (formerly Rhodesia)The term general practice is familiar to everyone 'in the medical profession who has been brought ' up in the British tradition of medicine. Nevertheless, there are a number of other terms which have been used to cover this branch of medicine. We are familiar with the family doctor, family physician, personal physician and others, but for the sake of definition we are considering in this paper the doctor who makes first contact on a personal basis with a person, be he seeking advice for an ailment from which he is already suffering or, perhaps more important, seeking advice whereby he might prevent an ailment occurring in the future

Micrococcal Nuclease Does Not Substantially Bias Nucleosome Mapping

We have mapped sequence-directed nucleosome positioning on genomic DNA molecules using high-throughput sequencing. Chromatins, prepared by reconstitution with either chicken or frog histones, were separately digested to mononucleosomes using either micrococcal nuclease (MNase) or caspase-activated DNase (CAD). Both enzymes preferentially cleave internucleosomal (linker) DNA, although they do so by markedly different mechanisms. MNase has hitherto been very widely used to map nucleosomes, although concerns have been raised over its potential to introduce bias. Having identified the locations and quantified the strength of both the chicken or frog histone octamer binding sites on each DNA, the results obtained with the two enzymes were compared using a variety of criteria. Both enzymes displayed sequence specificity in their preferred cleavage sites, although the nature of this selectivity was distinct for the two enzymes. In addition, nucleosomes produced by CAD nuclease are 8–10 bp longer than those produced with MNase, with the CAD cleavage sites tending to be 4–5 bp further out from the nucleosomal dyad than the corresponding MNase cleavage sites. Despite these notable differences in cleavage behaviour, the two nucleases identified essentially equivalent patterns of nucleosome positioning sites on each of the DNAs tested, an observation that was independent of the histone type. These results indicate that biases in nucleosome positioning data collected using MNase are, under our conditions, not significant

Vocalizations by Isolated Piglets: A Reliable Indicator of Piglet Need Directed Towards the Sow

When suckling piglets are isolated from the sow and litter-mates they vocalize a great deal. Sows also call when isolated from their piglets. In one experiment, we found that isolated piglets doubled their call rate in response to playback of sow calls, indicating that piglets are directing calls towards the sow. In a second experiment, we found that variation in the piglet isolation calls related to aspects of the piglet\u27s condition: piglets isolated for 13 min in an enclosure kept at approximately 14°C called more, used higher frequency calls and longer calls, than litter-mates isolated in an enclosure kept at 30°C. These differences in vocal behaviour were significant at 8 and 12 min of isolation, but not at 1, 2 or 4 min. These results for pigs correspond to those found with other species, indicating that characteristics of isolation calls can provide information about a young animal\u27s need for supplemental heat that can be supplied by the parent. The results also agree with a previous study on pigs, showing that features of these vocalizations vary with the piglet\u27s need for other resources such as milk

The pattern of sickness rates among employees of the posts and telecommunications corporation of Rhodesia

Sickness absenteeism from the Posts and Telecommunications Corporation of Rhodesia over the period July 1972 - June 1973 was reviewed. The 5709 employees took on average 1,5 days sick leave not covered by a doctor's certificate (a period of 3 days or less) and 3,1 days medically certified leave, giving a total average loss per person of 4,6 days (1,7% of working time). The commonest cause of medically certified leave was upper respiratory tract infections for Whites and off-duty injuries for Blacks. White females were absent twice as commonly as White males and 5 times as commonly as Black males. These differences were not due to an age disparity between the three groups.S. Afr. Med. J., 48, 1425 (1974)

Mindfulness and Indigenous Knowledge: Shared Narratives About Reconciliation and Decolonization in Teacher Education

This article discusses how shared narratives about mindfulness practices and Indigenous knowledge advance the reconciliation and the decolonization of Teacher Education curricula. We, the authors, experienced the beneficial impact of our personal mindfulness practices in nurturing and cultivating the harmonious balance of the physical, emotional, mental, and spiritual dimensions of the self. Within the context of the Truth and Reconciliation’s Calls to Action (2015), we observed the connections between mindfulness practices and local and place-based teachings of First Nation and Métis First Peoples in Northern British Columbia and in the Interior of British Columbia, Canada. Our experiences are informed by our personal mindfulness practices and from traditional and ancestral practices led by Elders and Knowledge Keepers. Our distinct narratives describe our learnings and our unlearnings as we participated in ceremony and listened and learnt from Elders and Knowledge Keepers of Syilx Okanagan Nation, Lheidli T’enneh First Nation, the Māori Nation, and the Métis Nation of Manitoba. By recognizing and respecting ancestral ways of doing and ways of being, we propose that contemplative practices like mindfulness can support a deeper understanding of how reconciliation and decolonizing are brought to the forefront of shared narratives in Teacher Education programs in the Okanagan and in Prince George