Faculty of Health Sciences (Research Outputs)

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Critical value reporting : a survey of 36 clinical laboratories in South Africa
(2014-01) Schapkaitz, E.; Mafika, Z.
Objective: Critical value policies are used by clinical laboratories to decide when to notify caregivers of life-threatening results. Despite their widespread use, critical value policies have not been published locally. A survey was designed to determine critical value policies for haematology tests in South Africa. Methods: A survey was carried out on 136 identified laboratories across South Africa in January 2013. Of these, 36 responded. Data collected included critical value policies, critical values for haematology parameters, and critical value reporting. Results: Of the 36 laboratories surveyed, 11.1% (n=4) were private, 33.3% (n=12) were affiliated to academic institutions and 55.6% (n=20) were peripheral or regional National Health Laboratory Service laboratories. All the laboratories confirmed that they had a critical value policy, and 83.3% of such policies were derived from local clinical opinion. Mean low and high critical limits for the most frequently listed tests were as follows: haemoglobin <6 and >20 g/dl, platelet count <41 and >1 000 ×109 /l, white cell count <2 and >46×109 /l, activated partial thromboplastin time >101 seconds, and international normalised ratio >6. In almost all cases critical value reporting was performed by the technologist on duty (97.2%). The majority of laboratories required that the person notified of the critical value be the doctor who ordered the test or the caregiver directly involved in the patient’s care (83.3%); 73.3% of laboratories indicated that they followed an algorithm if the doctor/caregiver could not be reached. Conclusion: Each laboratory is responsible for establishing clinically relevant critical limits. Clinicians should be involved in developing the laboratory’s critical value policy. The findings of this survey may be of value to local laboratories that are in the process of establishing or reviewing critical value policies
Laboratory information system data demonstrate successful implementation of the prevention of the mother- child transmission programme in South Africa
(2014-03) Sherman, G.G.; Lilian, R.R.; Bhardwaj, S.
Background: Monitoring the prevention of mother-to-child transmission (PMTCT) programme to identify gaps for early intervention is essential as South Africa progresses from prevention to elimination of HIV infection in children. Early infant diagnosis (EID) by an HIV polymerase chain reaction (PCR) test is recommended at 6 weeks of age for all HIV-exposed infants. The National Health Laboratory Service (NHLS) performs the PCR tests for the public health sector and stores test data in a corporate data warehouse (CDW). Objectives: To demonstrate the utility of laboratory data for monitoring trends in EID coverage and early vertical transmission rates and to describe the scale-up of the EID component of the PMTCT programme. Methods. HIV PCR test data from 2003 to 2012 inclusive were extracted from the NHLS CDW by year, province, age of infant tested and test result and used to calculate EID coverage and early vertical transmission rates to provincial level. Results: Rapid scale-up of EID over the first decade of the PMTCT programme was evident from the 100-fold increase in PCR tests to 350 000 by 2012. In 2012, 73% of the estimated 270 000 HIV-exposed infants requiring an early PCR were tested and the early vertical transmission rate had fallen to 2.4% as a result of successful implementation of the PMTCT programme. Conclusions: Laboratory data can provide real time, affordable monitoring of aspects of the PMTCT programme and assist in achieving virtual elimination of paediatric HIV infection in South Africa.
National sentinel site surveillance for antimicrobial resistance in Klebsiella pneumoniae isolates in South Africa, 2010-2012
(South African Medical Association, 2014-08) Perovic, O.; Singh- Moodley, A.; Duse, A.; Elliott, G.; Bamford, C.; Swe Swe-Han, K.; R Kularatne, R.; Lowman, W.; Whitelaw, A.; Nana, T.; Wadula, J.; Lekalakala, R.; Saif, A.; Marais, E.
Background: The increasing rates of antimicrobial resistance observed in the nosocomial pathogen Klebsiella pneumoniae are of major public health concern worldwide. Objectives: To describe the antibiotic susceptibility profiles of K. pneumoniae isolates from bacteraemic patients submitted by sentinel laboratories in five regions of South Africa from mid-2010 to mid-2012. Molecular methods were used to detect the most commonly found extended-spectrum beta lactamase (ESBL) and carbapenemase resistance genes. Methods: Thirteen academic centres serving the public healthcare sector in Gauteng, KwaZulu-Natal, Free State, Limpopo and Western Cape provinces submitted K. pneumoniae isolates from patients with bloodstream infections. Vitek 2 and MicroScan instruments were used for organism identification and susceptibility testing. Multiplex polymerase chain reactions (PCRs) were used to detect blaCTX-M, blaSHV and blaTEM genes in a proportion of the ESBL isolates. All isolates exhibiting reduced susceptibility to carbapenems were PCR tested for blaKPC and blaNDM-1 resistance genes. Results: Overall, 68.3% of the 2 774 isolates were ESBL-positive, showing resistance to cefotaxime, ceftazidime and cefepime. Furthermore, 46.5% of all isolates were resistant to ciprofloxacin and 33.1% to piperacillin-tazobactam. The major ESBL genes were abundantly present in the sample analysed. Most isolates (95.5%) were susceptible to the carbapenems tested, and no isolates were positive for blaKPC or blaNDM-1. There was a trend towards a decrease in susceptibility to most antibiotics. Conclusion: The high proportion of ESBL-producing K. pneumoniae isolates observed, and the prevalence of ESBL genes, are of great concern. Our findings represent a baseline for further surveillance in SA, and can be used for policy and treatment decisions.
Blood pressure measurements in the ankle are not equivalent to blood pressure measurements in the arm
(2014-12) Goldstein, L.N.; Wells, M.; Sliwa, K.
Background. Blood pressure (BP) is often measured on the ankle in the emergency department (ED), but this has never been shown to be an acceptable alternative to measurements performed on the arm. Objective. To establish whether the differences between arm and ankle non-invasive BP measurements were clinically relevant (i.e. a difference of ≥10 mmHg). Methods. This was a prospective cross-sectional study in an urban ED making use of a convenience sample of 201 patients (18 - 50 years of age) who were not in need of emergency medical treatment. BP was measured in the supine position on both arms and ankles with the correct size cuff according to the manufacturer’s guidelines. The arm and ankle BP measurements were compared. Results. There was a clinically and statistically significant difference between arm and ankle systolic BP (SBP) and mean arterial pressure (MAP) (–13 mmHg, 95% confidence interval (CI) –28 - 1 mmHg and –5 mmHg, 95% CI –13 - 4 mmHg, respectively), with less difference in diastolic BP (DBP) (2 mmHg, 95% CI –7 - 10 mmHg). Only 37% of SBP measurements and 83% of MAP measurements were within an error range of 10 mmHg, while 95% of DBP measurements agreed within 10 mmHg. While the average differences (or the bias) were generally not large, large variations in individual patients (indicating poor precision) made the prediction of arm BP from ankle measurements unreliable. Conclusion. Ankle BP cannot be used as a substitute for arm BP in the ED.
Factors influencing access of pregnant women and their infants to their local healthcare system: a prospective, multicentre, observational study
(BMC, 2018) Madhi, Shabir A.; Rivera, Luis M.; Sáez-Llorens, Xavier; Menéndez, Clara; Carrim-Ganey, Nazira; Cotton, Mark F.; Katzman, Darren; Luttig, Mariëtha M.; Candelario, Rosalba; Baker, Sherryl; Roychoudhury, Mahua
Background: The successful implementation of maternal vaccination relies on results of clinical trials, considering the prenatal and postnatal attendance at selected healthcare institutions. This study evaluated factors influencing maternal/infant access to healthcare facilities to identify potential barriers to participation in future clinical trials on maternal vaccination. Methods: In this prospective, multi-centre, observational study, pregnant women (N = 3243) were enrolled at ten sites across Panama, the Dominican Republic, South Africa, and Mozambique between 2012 and 2014. They completed questionnaires at enrolment, delivery, and infant follow-up (90 days post-partum) visits, including questions on transportation, phone accessibility, alternative childcare, gestational age at enrolment, delivery location, and health status of their infant. Logistic regression was used to identify factors significantly associated with return to study site for delivery or infant follow-up visits. Results: Among 3229 enrolled women with delivery information, 63.6% (range across sites: 25.3–91.5%) returned to study site for delivery. Older women and those at later gestational age at enrolment were more likely to deliver at the study site. While heterogeneities were observed at site level, shorter travel time at delivery and increased transportation costs at enrolment were associated with increased likelihood of women returning to study site for delivery. Among 3145 women with live-born infants, 3077 (95.3%) provided 90-day follow-up information; of these, 68.9% (range across sites: 25.6–98.9%) returned to study site for follow-up visits. Women with other children and with lower transportation costs at delivery were more likely to return to study site for follow-up visits. Among 666 infants reported sick, 94.3% were taken to a healthcare facility, with only 41.9% (range across sites: 4.9–77.3%) to the study site. Conclusion: Although high retention was observed from enrolment through 90 days after delivery, post-partum surveillance should be broadened beyond the study sites and additional follow-up visits should be planned within the neonatal period. The factors influencing maternal/infant access to healthcare facilities and the issues identified in this study should be taken into consideration in planning future clinical studies on maternal immunisation in low- and middle-income countries.
Cash transfer interventions for sexual health: meanings and experiences of adolescent males and females in inner-city Johannesburg
(BMC, 2018) Khoza, Nomhle; Stadler, Jonathan; MacPhail, Catherine; Chikandiwa, Admire; Brahmbhatt, Heena; Delany-Moretlwe, Sinead
Background: In sub-Saharan Africa, there is growing interest in the use of cash transfer (CT) programs for HIV treatment and prevention. However, there is limited evidence of the consequences related to CT provision to adolescents in low-resourced urban settings. We explored the experiences of adolescents receiving CTs to assess the acceptability and unintended consequences of CT strategies in urban Johannesburg, South Africa. Methods: We collected qualitative data during a pilot randomized controlled trial of three CT strategies (monthly payments unconditional vs. conditional on school attendance vs. a once-off payment conditional on a clinic visit) involving 120 adolescents aged 16–18 years old in the inner city of Johannesburg. Interviews were conducted in isiZulu, Sesotho or English with a sub-sample of 49 participants who adhered to study conditions, 6 months after receiving CT (280 ZAR/ 20 USD) and up to 12 months after the program had ended. Interviews were transcribed and translated by three fieldworkers. Codes were generated using an inductive approach; transcripts were initially coded based on emerging issues and subsequently coded deductively using Atlas.ti 7.4. Results: CTs promoted a sense of independence and an adult social identity amongst recipients. CTs were used to purchase personal and household items; however, there were gender differences in spending and saving behaviours. Male participants’ spending reflected their preoccupation with maintaining a public social status through which they asserted an image of the responsible adult. In contrast, female participants’ expenditure reflected assumption of domestic responsibilities and independence from older men, with the latter highlighting CTs’ potential to reduce transactional sexual partnerships. Cash benefits were short-lived, as adolescents reverted to previous behavior after the program’s cessation. Conclusion: CT programs offer adolescent males and females in low-income urban settings a sense of agency, which is vital for their transition to adulthood. However, gender differences in the expenditure of CTs and the effects of ending CT programs must be noted, as these may present potential unintended risks.
Social health insurance contributes to universal coverage in South Africa, but generates inequities: survey among members of a government employee insurance scheme
(BMC, 2018) Goudge, Jane; Harris, Bronwyn; Nxumalo, Nonhlanhla; Chersich, Matthew F.; Alaba, Olufunke A.; Govender, Veloshnee
Background: Many low- and middle-income countries are reforming their health financing mechanisms as part of broader strategies to achieve universal health coverage (UHC). Voluntary social health insurance, despite evidence of resulting inequities, is attractive to policy makers as it generates additional funds for health, and provides access to a greater range of benefits for the formally employed. The South African government introduced a voluntary health insurance scheme (GEMS) for government employees in 2005 with the aim of improving access to care and extending health coverage. In this paper we ask whether the new scheme has assisted in efforts to move towards UHC. Methods: Using a cross-sectional survey across four of South Africa’s nine provinces, we interviewed 1329 government employees, from the education and health sectors. Data were collected on socio-demographics, insurance coverage, health status and utilisation of health care. Multivariate logistic regression was used to determine if service utilisation was associated with insurance status. Results: A quarter of respondents remained uninsured, even higher among 20–29 year olds (46%) and lower-skilled employees (58%). In multivariate analysis, the odds of an outpatient visit and hospital admission for the uninsured was 0.3 fold that of the insured. Cross-subsidisation within the scheme has provided lower-paid civil servants with improved access to outpatient care at private facilities and chronic medication, where their outpatient (0.54 visits/ month) and inpatient utilisation (10.1%/year) approximates that of the overall population (29.4/month and 12.2% respectively). The scheme, however, generated inequities in utilisation among its members due to its differential benefit packages, with, for example, those with the most benefits having 1.0 outpatient visits/month compared to 0.6/ month with lowest benefits. Conclusions: By introducing the scheme, the government chose to prioritise access to private sector care for government employees, over improving the availability and quality of public sector services available to all. Government has recently regained its focus on achieving UHC through the public system, but is unlikely to discontinue GEMS, which is now firmly established. The inequities generated by the scheme have thus been institutionalised within the country’s financing system, and warrant attention. Raising scheme uptake and reducing differentials between benefit packages will ameliorate inequities within civil servants, but not across the country as a whole.
The effect of a ketogenic diet versus a high-carbohydrate, low-fat diet on sleep, cognition, thyroid function, and cardiovascular health independent of weight loss: study protocol for a randomized controlled trial
(BMC, 2018) Iacovides, Stella; Meiring, Rebecca M.
Background: Many physiological health benefits observed after following a ketogenic diet (KD) can be attributed to the associated weight loss. The KD has become more prominent as a popular health choice, not only in obese/overweight individuals, but also in healthy adults. The study aims to determine the effects of a KD, independent of weight loss, on various aspects of physiological health including: sleep, thyroid function, cognition, and cardio-metabolic health. The study will also aim to determine whether a change in basal metabolic rate may be associated with any changes observed. Methods: Twenty healthy men and women between 18 and 50 years of age will take part in this study. In a randomized controlled, cross-over design, participants will follow two isocaloric diets: a high-carbohydrate, low-fat diet (55% CHO, 20% fat, 25% protein) and a KD (15% CHO, 60% fat, 25% protein). Each dietary intervention will last for a minimum of 3 weeks, with a 1-week washout period in between. Before and after each diet, participants will be assessed for sleep quality, cognitive function, thyroid function, and basal metabolic rate. A blood sample will also be taken for the measurement of cardio-metabolic and immune markers. Discussion: The present study will help in understanding the potential effects of a KD on aspects of physiological health in healthy adults, without the confounding factor of weight loss. The study aims to fill a significant void in the academic literature with regards to the benefits and/or risks of a KD in a healthy population, but will also explore whether diet-related metabolic changes may be responsible for the changes observed in physiological health.
The importance of morphological identification of African anopheline mosquitoes (Diptera: Culicidae) for malaria control programmes
(BioMed Central (BMC), 2018-01) Erlank, Erica; Koekemoer, Lizette L.; Coetzee, Maureen
Background: The correct identification of disease vectors is the first step towards implementing an effective control programme. Traditionally, for malaria control, this was based on the morphological differences observed in the adults and larvae between different mosquito species. However, the discovery of species complexes meant that genetic tools were needed to separate the sibling species and today there are standard molecular techniques that are used to identify the two major malaria vector groups of mosquitoes. On the assumption that species-diagnostic DNA polymerase chain reaction (PCR) assays are highly species-specific, experiments were conducted to investigate what would happen if non-vector species were randomly included in the molecular assays. Methods: Morphological keys for the Afrotropical Anophelinae were used to provide the a priori identifications. All mosquito specimens were then subjected to the standard PCR assays for members of the Anopheles gambiae complex and Anopheles funestus group. Results: One hundred and fifty mosquitoes belonging to 11 morphological species were processed. Three species (Anopheles pretoriensis, Anopheles rufipes and Anopheles rhodesiensis) amplified members of the An. funestus group and four species (An. pretoriensis, An. rufipes, Anopheles listeri and Anopheles squamosus) amplified members of the An. gambiae complex. Conclusions: Morphological identification of mosquitoes prior to PCR assays not only saves time and money in the laboratory, but also ensures that data received by malaria vector control programmes are useful for targeting the major vectors.
Molecular and physiological analysis of Anopheles funestus swarms in Nchelenge, Zambia
(BMC, 2018-01) Zawada, Jacek W.; Dahan‑Moss, Yael L.; Muleba, Mbanga; Dabire, Roch K.; Maïga, Hamid; Venter, Nelius; Davies, Craig; Hunt, Richard H.; Coetzee, Maureen; Koekemoer, Lizette L.
Background: Anopheles funestus has been recognized as a major malaria vector in Africa for over 100 years, but knowledge on many aspects of the biology of this species is still lacking. Anopheles funestus, as with most other anophelines, mate through swarming. A key event that is crucial for the An. funestus male to mate is genitalia rotation. This involves the 135° to 180° rotation of claspers, which are tipped with claws. This physical change then enables the male to grasp the female during copulation. The aim of this investigation was to molecularly characterize wild An. funestus swarms from Zambia and examine the degree of genitalia rotation within the swarm. Methods: Anopheles funestus swarms were collected from Nchelenge, northern Zambia, during dusk periods in May 2016. All the adults from the swarm were analysed morphologically and identified to species level using a multiplex PCR assay. Anopheles funestus s.s. specimens were molecularly characterized by restriction fragment length polymorphism type and Clade type assays. The different stages of genitalia rotation were examined in the adult males. Results: A total of six swarms were observed during the study period and between 6 and 26 mosquitoes were caught from each swarm. Species analysis revealed that 90% of the males from the swarms were An. funestus s.s. MWtype, with 84% belonging to clade I compared to 14% clade II and 2% failed to amplify. Very few specimens (3.4%) were identified as Anopheles gambiae s.s. Eighty percent of the males from the swarm had complete genitalia rotation. Conclusions: This is the first time that An. funestus swarms have been molecularly identified to species level. Anopheles funestus swarms appear to be species-specific with no evidence of clade-type differentiation within these swarms. The An. funestus swarms consist mainly of males with fully rotated genitalia, which strongly suggests that swarming behaviour is triggered primarily when males have matured.
Perceptions of counsellors and youth-serving professionals about sexual and reproductive health services for adolescents in Soweto, South Africa
(BMC, 2018-02) Mulaudzi, Mamakiri; Dlamini, Busisiwe Nkala; Coetzee, Jenny; Sikkema, Kathleen; Gray, Glenda; Dietrich, Jana Janine
Background: Adolescents in South Africa remain vulnerable to HIV. Therefore, it is crucial to provide accessible adolescent-friendly HIV prevention interventions that are sensitive to their needs. This study aimed to investigate the perceptions of HIV counsellors and other youth-serving professionals about the barriers to providing adolescent youth-friendly sexual and reproductive health services to adolescents in Soweto, South Africa. The study also explored how sexual and reproductive health services in South Africa could be improved to become more accessible to adolescents. Methods: The research team conducted two focus group discussions with HIV counsellors, and 19 semi-structured interviews with youth-serving professionals from organisations working with adolescents. Audio-recorded data were transcribed verbatim and analysed using thematic analysis. Results: The results of the study reveal that counsellors were expected to give adolescents HIV counselling and testing (HCT) but felt restricted by what they perceived as inflexible standard operating procedures. Counsellors reported inadequate training to address adolescent psychosocial issues during HCT. Healthcare provider attitudes were perceived as a barrier to adolescents using sexual and reproductive health services. Participants strongly recommended augmenting adolescent sexual and reproductive health services to include counsellors and adolescents in developing age- and context-specific HIV prevention services for adolescents. Conclusion: Continuous upskilling of HIV counsellors is a critical step in providing adolescent-friendly services.
Influence of vitamin D receptor polymorphisms on biochemical markers of mineral bone disorders in South African patients with chronic kidney disease
(2018-02) Waziri, Bala; Dix-Peek, Therese; Dickens, Caroline; Duarte, Raquel; Naicker, Saraladevi
Background: It remains unclear whether genetic factors may explain the reported variation in the levels of biochemical markers of chronic kidney disease mineral and bone disorders (CKD- MBD) across ethnic groups. Therefore, the aim of this study was to examine the influence of vitamin D receptor (VDR) polymorphisms on secondary hyperparathyroidism and its association with vitamin D levels in black and white South African study participants. Methods: This was a cross sectional study involving 272 CKD stage 3- 5D patients and 90 healthy controls. The four major VDR polymorphisms (Bsm 1, Fok 1, Taq 1, and Apa1) were genotyped using the polymerase chain reaction- restriction fragment length polymorphism (PCR –RFLP) method. In addition, biochemical markers of CKD-MBD were measured to determine their associations with the four VDR polymorphisms. Results: With the exception of Taq I polymorphism, the distribution of the VDR polymorphisms differed significantly between blacks and whites. In hemodialysis patients, the Bb genotype was significantly associated with moderate secondary hyperparathyroidism (OR, 3.88; 95 CI 1.13–13.25, p = 0.03) and severe hyperparathyroidism (OR, 2.54; 95 CI 1.08–5.96, p = 0.03). This was consistent with the observed higher levels of median parathyroid hormone, fibroblast growth factor 23 and mean phosphate in patients with Bb genotype. This candidate risk genotype (Bb) was over represented in blacks compared to whites (71.0% versus 55.6%, p < 0.0001). In an unadjusted regression model, FokFf genotype was found to be significantly associated with the risk of developing severe vitamin D deficiency < 15 ng/ml (OR, 1.89; 95 CI 1.17–3.07, p = 0.01). Conclusion: The VDR Bb genotype is an independent predictor of developing secondary hyperparathyroidism in patients with end stage kidney disease. In addition, study participants with FokFf genotype are at increased of developing severe 25 -hydroxyvitamin D [25(OH)D] deficiency.
Aqueous extract of moringa (Moringa oleifera) leaf (AEMOL) on the growth, sensory and histology parameters of broiler chickens
(ALÖKI Kft, 2020-07) Mbajiorgu, Ejikeme F.; Alabi, O. J.; Ng’Ambi, J. W.
A completely randomized design experiment was used to determine the effects of aqueous extract of Moringa oleifera leaf (AEMOL) on growth, sensory and histology parameters of broiler chickens. Treatment 1 served as the control (antibiotics), Treatment two was given ordinary water (AEMOL0). Treatments 3, 4, 5 and 6 contained 30, 60, 90 and 120 ml of AEMOL per litre of water per day, respectively. Data obtained were analyzed using one-way analysis of variance and mean separation was done using Duncan’s test for multiple comparisons. Results showed that the extract influenced (P < 0.05) the feed intake and water intake at the broiler starter phase WHILE birds on the control diet had higher values. Finisher phase results showed that final weight, weight gain, feed intake, FCR and water intake were influenced (P < 0.05) by the extract with birds treated with 60 ml/l of AEMOL doing better for most parameters except the FCR. All the digestibility and sensory parameters measured were also influenced (P < 0.05) by the extract. However, histological parameters measured were not affected (P > 0.05) by the extract. It could be concluded that the extract inclusion levels up to 90 ml/l can be used to replace antibiotic growth promoter without compromising the advantages of antibiotic growth promoter.
Tamoxifen induces hypercoagulation and alterations in ERα and ERβ dependent on breast cancer sub‑phenotype ex vivo
(Nature, 2020-11-06) Pather, Kyrtania; Augustine, T. N.
Tamoxifen shows efficacy in reducing breast cancer-related mortality but clinically, is associated with increased risk for thromboembolic events. We aimed to determine whether breast tumour subphenotype could predict propensity for thrombosis. We present two ex vivo Models of Tamoxifentherapy, Model 1 in which treatment recapitulates accumulation within breast tissue, by treating MCF7 and T47D cells directly prior to exposure to blood constituents; and Model 2 in which we recreate circulating Tamoxifen by treating blood constituents prior to exposure to cancer cells. Blood constituents included whole blood, platelet-rich plasma and platelet-poor plasma. Hypercoagulation was assessed as a function of thrombin activity, expression of CD62P and CD63 activation markers defined as an index of platelet activation, and platelet morphology; while oestrogen receptor expression was assessed using immunocytochemistry with quantitative analysis. We determined, in concert with clinical studies and contrary to selected laboratory investigations, that Tamoxifen induces hypercoagulation, dependent on sub-phenotypes, with the T47D cell line capacity most enhanced. We determined a weak positive correlation between oestrogen receptor expression, and CD62P and CD63; indicating an association between tumour invasion profiles and hypercoagulation, however, other yet unknown factors may play a predictive role in defining hypercoagulation.
Harnessing Thor’s Hammer: Experimentally induced lightning trauma to human bone by high impulse current.
(Elsevier B.V., 2021) Bacci, Nicholas; Audustine, Tanya N.; Hunt, Hugh G. P.; Nixon, Ken J.; Hoffman, Jakobus; Bam, Lunga; de Beer, Frikkie; Randolph-Quinney, Patrick
Lightning fatality identification relies primarily on soft tissue traumatic pattern recognition, prohibiting cause of death identification in cases of full skeletonisation. This study explores the effects of high impulse currents on human bone, simulating lightning-level intensities and characterising electrically induced micro-trauma through conventional thin-section histology and micro-focus X-ray computed tomography (μXCT). An experimental system for high impulse current application was applied to bone extracted from donated cadaveric lower limbs (n = 22). μXCT was undertaken prior to and after current application. Histological sections were subsequently undertaken. μXCT poorly resolved micro-trauma compared to conventional histology which allowed for identification and classification of lightning-specific patterns of micro-trauma. Statistical analyses demonstrated correlation between current intensity, extent and damage typology suggesting a multifaceted mechanism of trauma propagation - a combination of electrically, thermally and pressure induced alterations. This study gives an overview of high impulse current trauma to human bone, providing expanded definitions of associated micro-trauma.
Development of the Wits Face Database: an African database of high-resolution facial photographs and multimodal closedcircuit television (CCTV) recordings [version 1; peer review: 2 approved]
(2021) Bacci, Nicholas; Davimes, Joshua; Steyn, Maryna; Briers, Nanette
Forensic facial comparison is a commonly used, yet under-evaluated method employed in medicolegal contexts across the world. Testing the accuracy and reliability of facial comparisons requires large scale controlled and matching facial image databases. Databases that contain images of individuals on closed-circuit television (CCTV), with matching formal and informal photographs are needed for this type of research. Although many databases are available, the majority if not all are developed in order to improve facial recognition and face detection algorithms through machine learning, with very limited if any measure of standardisation. This paper aims to review the available databases and describe the development of a high resolution, standardised facial photograph and CCTV recording database of male Africans. The database is composed of a total of 6220 standardised and uncontrolled suboptimal facial photographs of 622 matching individuals in five different views, as well as corresponding CCTV footage of 334 individuals recorded under different realistic conditions. A detailed description of the composition and acquisition process of the database as well as its subdivisions and possible uses are provided. The challenges and limitations of developing this database are also highlighted, particularly with regard to obtaining CCTV video recordings and ethics for a database of faces. The application process to access the database is also briefly described.
Antiplatelet Therapy Combined with Anastrozole Induces Features of Partial EMT in Breast Cancer Cells and Fails to Mitigate Breast-Cancer Induced Hypercoagulation
(MDPI, 2021-04-16) Xulu, Kutlwano R.; Augustine, Tanya N.
Thromboembolic complications are a leading cause of morbidity and mortality in cancer patients. Cancer patients often present with an increased risk for thrombosis including hypercoagulation, so the application of antiplatelet strategies to oncology warrants further investigation. This study investigated the effects of anastrozole and antiplatelet therapy (aspirin/clopidogrel cocktail or atopaxar) treatment on the tumour responses of luminal phenotype breast cancer cells and induced hypercoagulation. Ethical clearance was obtained (M150263). Blood was co-cultured with breast cancer cell lines (MCF7 and T47D) pre-treated with anastrozole and/or antiplatelet drugs for 24 h. Hypercoagulation was indicated by thrombin production and platelet activation (morphological and molecular). Gene expression associated with the epithelial-to-mesenchymal transition (EMT) was assessed in breast cancer cells, and secreted cytokines associated with tumour progression were evaluated. Data were analysed with the PAST3 software. Our findings showed that antiplatelet therapies (aspirin/clopidogrel cocktail and atopaxar) combined with anastrozole failed to prevent hypercoagulation and induced evidence of a partial EMT. Differences in tumour responses that modulate tumour aggression were noted between breast cancer cell lines, and this may be an important consideration in the clinical management of subphenotypes of luminal phenotype breast cancer. Further investigation is needed before this treatment modality (combined hormone and antiplatelet therapy) can be considered for managing tumour associated-thromboembolic disorder.
Forensic facial comparison: current status, limitations, and future directions.
(MDPI, 2021-12-03) Bacci, Nicholas; Davimes, Joshua G.; Steyn, Maryna; Briers, Nanette
Global escalation of crime has necessitated the use of digital imagery to aid the identification of perpetrators. Forensic facial comparison (FFC) is increasingly employed, often relying on poorquality images. In the absence of standardized criteria, especially in terms of video recordings, verification of the methodology is needed. This paper addresses aspects of FFC, discussing relevant terminology, investigating the validity and reliability of the FISWG morphological feature list using a new South African database, and advising on standards for CCTV equipment. Suboptimal conditions, including poor resolution, unfavorable angle of incidence, color, and lighting, affected the accuracy of FFC. Morphological analysis of photographs, standard CCTV, and eye-level CCTV showed improved performance in a strict iteration analysis, but not when using analogue CCTV images. Therefore, both strict and lenient iterations should be conducted, but FFC must be abandoned when a strict iteration performs worse than a lenient one. This threshold ought to be applied to the specific CCTV equipment to determine its utility. Chance-corrected accuracy was the most representative measure of accuracy, as opposed to the commonly used hit rate. While the use of automated systems is increasing, trained human observer-based morphological analysis, using the FISWG feature list and an Analysis, Comparison, Evaluation, and Verification (ACE-V) approach, should be the primary method of facial comparison.
The diagenetic alterations of historic skeletons from the Crown Mines Cemetery, South Africa
(2023) Lander, Stacey L.; Brits, Desiré ; Hosie, Margot
Human skeletons associated with early gold mining in Johannesburg, South Africa are investigated. An unmarked cemetery was buried beneath a mine dump which resulted in macroscopically stained and poorly preserved bones. Histological assessments were conducted to understand the postmortem treatment of the remains, determine the extent of bone degradation, and understand how this environment affected the bone’s microstructure. Various diagenetic alterations and the general histological index were assessed using normal and polarized light microscopy of thin anterior midshaft femur sections (n = 50). Degradation was identified in the periosteal and endosteal regions, while the intra-cortical region remained well-preserved. Bacterial bioerosion, microcracks, infiltrations, inclusions, and staining were found throughout the sample. Numerous non-Wedl micro-foci of destruction were observed, filled with exogenous material. The degradation suggested that the remains were buried in neutral soil that was subsequently covered by acidic mine dumps which resulted in a corrosive environment. Although the skeletons were poorly preserved, their histological integrity was more promising, especially the intra-cortical area. This is important for future investigations of archaeological bone, as this area can lead to more accurate descriptions of skeletal assemblages. Targeted sampling of this region could produce promising estimates of age, descriptions of pathology, and biomolecular results, which require further study.
Maternal perceptions of infant's body weight and childhood obesity in South Africa: a qualitative study in Soweto
(Wiley, 2023) Norris, Shane A.; Cohen, Emmanuel; Wrottesley, Stephanie V.; Prioreschi, Alessandra; Slemming, Wiedaad
From a socio-anthropological study focusing on maternal body weight perceptions and dietary practices towards infants living in Soweto (South Africa), we studied how lay sociocultural traits may lead to early childhood obesity. Most mothers tended to socially value and normalize fatness. This propensity led mothers, particularly older women at home, to adopt high-calorie feeding practices towards infants, although some mothers tended to question these lay norms. Further works must consider how lay (emic) sociocultural norms in African townships can contradict biomedical (etic) messages, conveying for the community thinness as the acceptable standard, and may expose infants to early obesity.

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