Factors influencing peak expiratory flow in teenage boys

Background. Peak expiratory flow (PEF) is a useful measure of pulmonary health status and is frequently utilised in asthm, management. Reduction in PEF is usually indicative of OIlS( of asthma symptoms. However, use can be made of PEF values only if normal values are known. The definition of normal range is always difficult and may vary between regions and be affected by a variety of factors.Objective. To establish PEF values for teenage boys in a Cape Town suburb and examine factors that possibly influence this measurement.Setting. A high school for boys in the southern suburbs of Cape Town.Methods. Measurements of PEF were taken for 124 boys. Subjects were approximately 16 years old and apparently healthy at the time of survey. Further details were provid by means of a questionnaire.Results. PEF ranged from 350 to 760 1/min, with a mean (± standard deviation (SD» of 539 ± 681/min. Factors expected to influence PEF included height and mass, where is unexpected factors included sport intensity and academic grade. A trend to reduced peak flow was already evident in boys who smoked and boys from homes where a parent smoked. Regression analysis suggested peak flow differenct.s in our population compared with the standard reference.Conclusion. Interpretation of results obtained from peak-flow instruments should take into account additional knowledge concerning the individual. Further surveys of the South African population and of different groups should be done to establish local standards and factors influencing PE

Genetic resistance to Mycobacterium Tuberculosis infection and disease

CITATION: Möller, M. et al. 2018. Genetic resistance to Mycobacterium tuberculosis infection and disease. Frontier in Immunology, 9:2219, 1-13. doi:10.3389/fimmu.2018.02219.The original publication is available from https://www.frontiersin.org/journals/immunology#Natural history studies of tuberculosis (TB) have revealed a spectrum of clinical outcomes after exposure to Mycobacterium tuberculosis, the cause of TB. Not all individuals exposed to the bacteriumwill become diseased and depending on the infection pressure, many will remain infection-free. Intriguingly, complete resistance to infection is observed in some individuals (termed resisters) after intense, continuing M. tuberculosis exposure. After successful infection, the majority of individuals will develop latent TB infection (LTBI). This infection state is currently (and perhaps imperfectly) defined by the presence of a positive tuberculin skin test (TST) and/or interferon gamma release assay (IGRA), but no detectable clinical disease symptoms. The majority of healthy individuals with LTBI are resistant to clinical TB, indicating that infection is remarkably well-contained in these non-progressors. The remaining 5–15% of LTBI positive individuals will progress to active TB. Epidemiological investigations have indicated that the host genetic component contributes to these infection and disease phenotypes, influencing both susceptibility and resistance. Elucidating these genetic correlates is therefore a priority as it may translate to new interventions to prevent, diagnose or treat TB. The most successful approaches in resistance/susceptibility investigation have focused on specific infection and disease phenotypes and the resister phenotype may hold the key to the discovery of actionable genetic variants in TB infection and disease. This review will not only discuss lessons from epidemiological studies, but will also focus on the contribution of epidemiology and functional genetics to human genetic resistance to M. tuberculosis infection and disease.https://www.frontiersin.org/articles/10.3389/fimmu.2018.02219/fullhttps://doi.org/10.3389/fimmu.2018.02219Published review articlePublishers versio

Determining ancestry proportions in complex admixture scenarios in South Africa using a novel proxy ancestry selection method

Admixed populations can make an important contribution to the discovery of disease susceptibility genes if the parental populations exhibit substantial variation in susceptibility. Admixture mapping has been used successfully, but is not designed to cope with populations that have more than two or three ancestral populations. The inference of admixture proportions and local ancestry and the imputation of missing genotypes in admixed populations are crucial in both understanding variation in disease and identifying novel disease loci. These inferences make use of reference populations, and accuracy depends on the choice of ancestral populations. Using an insufficient or inaccurate ancestral panel can result in erroneously inferred ancestry and affect the detection power of GWAS and meta-analysis when using imputation. Current algorithms are inadequate for multi-way admixed populations. To address these challenges we developed PROXYANC, an approach to select the best proxy ancestral populations. From the simulation of a multi-way admixed population we demonstrate the capability and accuracy of PROXYANC and illustrate the importance of the choice of ancestry in both estimating admixture proportions and imputing missing genotypes

High diversity, inbreeding and a dynamic Pleistocene demographic history revealed by African buffalo genomes

CITATION: De Jager, D., et al. 2021. High diversity, inbreeding and a dynamic Pleistocene demographic history revealed by African buffalo genomes. Scientific Reports, 11:4540, doi:/10.1038/s41598-021-83823-8.The original publication is available at https://www.nature.comPublication of this article was funded by the Stellenbosch University Open Access FundGenomes retain records of demographic changes and evolutionary forces that shape species and populations. Remnant populations of African buffalo (Syncerus caffer) in South Africa, with varied histories, provide an opportunity to investigate signatures left in their genomes by past events, both recent and ancient. Here, we produce 40 low coverage (7.14×) genome sequences of Cape buffalo (S. c. caffer) from four protected areas in South Africa. Genome-wide heterozygosity was the highest for any mammal for which these data are available, while differences in individual inbreeding coefficients reflected the severity of historical bottlenecks and current census sizes in each population. PSMC analysis revealed multiple changes in Ne between approximately one million and 20 thousand years ago, corresponding to paleoclimatic changes and Cape buffalo colonisation of southern Africa. The results of this study have implications for buffalo management and conservation, particularly in the context of the predicted increase in aridity and temperature in southern Africa over the next century as a result of climate change.https://www.nature.com/articles/s41598-021-83823-8Publisher's versio

A Mobile Holistic Enterprise Transformation Framework

Mobile phones and tablets shipments are surpassing those of the PC category, as well as in relation to Internet usage as of 2016; all details which have made mobile adoption a priority for many enterprises and a challenge for them as well. Many enterprises have fallen into a paradox of spending on creating and updating mobile services, and gaining less than expected in return. Reasons for this include the lack of vision, and the lack of a clearly defined, well communicated mobile strategy. Enterprise Architecture ‘EA’ facilitates a successful transformation by controlling and managing the transitions in order to arrive at a clearly defined future state. It is regarded as the science of change to many. However, EA frameworks are very comprehensive and require weeks of training and resources, and are often too generic for mobile transformation. Therefore, an EA-based mobile holistic enterprise framework has been developed to support enterprises in making mobile initiatives a priority. The proposed framework ensures a clearly defined, well-communicated, holistic future state that is continually evaluated, as opposed to many of the existing frameworks. The proposed Mobile Holistic Enterprise Architecture Framework - ‘MHETF’ - is based on the realisation of the capabilities of smartphones that are aimed at individual average consumers (the backbone of the current mobile trend). The capabilities are categorised and translated into four sets of services categories for business use. They are linked to another two components of the framework which are: (i) the categorisation of goals and objectives that are incorporated into the Balanced Scorecard for evaluation at a later stage in planning, and continually referred to during transitions and (ii) the categorisation of the implementation forms (categorisation of end solutions’ functionalities). The framework is supported by EA inter-operability and maturity models to ensure continuity and alignment with the existing initiatives, the enterprise’s strategic objectives, and the change required in the scope of transformation. An evaluation for the available enterprise architecture frameworks was carried out and resulted in the selection of The Open Group Architecture Framework (TOGAF). The decision was also commended by the participants in the case study evaluation due to their familiarity with this framework, which is being adopted as the Saudi E Government Standard in contrast to the other major frameworks of Zachman and Federal Enterprise Architecture (FEA). MHETF has been applied to three case studies in the Kingdom of Saudi Arabia; two applications for a leading national outsourcing company, and the third for the outpatient clinics in a large hospital in the capital city of Riyadh. The results have shown major improvements in the four goal areas of mobile transformation; productivity, processes, satisfaction improvement and facilitating new opportunities. Eventually, the final evolution has shown that the participants are satisfied with the framework overall, and indicates that the framework changed their perspective of the power of mobile applications significantly, is relatively easy to understand, and that they are planning to adopt it for future mobile initiatives