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- ItemOpen AccessGenetics of suicidality: Genomics as a means of understanding the overlap between suicidal behaviour and schizophrenia(2026) Mshunqwane, Pheziwe; Ramesar, Rajkumar; Dalvie ShareefaIntroduction: Suicidal behaviour (SB), encompassing attempted suicide and completed suicide,and other related phenotypes, is one of the leading causes of death and disease burden worldwide. Studies have shown that suicide attempt is a major predictor of completed suicide. Moreover, psychiatric disorders such as schizophrenia (SCZ) have been identified as a major risk factor for SB. Both suicide attempt and SCZ have a strong genetic component, with heritability estimates of 17-55% and 41-87%, respectively. Previous studies have demonstrated that while these two phenotypes are genetically distinct, they also show a significant genetic overlap. However, most previous research has been conducted predominantly in individuals of European (EUR) ancestry, with limited data available in the African (AFR) context. The AFR genome has the highest genetic diversity, offering great potential for uncovering novel genetic variants. Therefore, the aim of this study was to investigate the distinct and overlapping genetic architecture of suicide attempt and SCZ in South African cohorts. This was done by: (1) selecting 20 genetic variants previously associated with SB and evaluating their association with suicide attempt in a local cohort; (2) identifying genetic variants associated with SCZ in an indigenous (local) cohort for which whole exome sequencing data was generated; (3) examining the extent of genetic correlation between suicide attempt and SCZ; and (4) assessing whether polygenic risk score (PRS) for suicide attempt can predict SCZ . Methods: A candidate gene-based case-control association study (133 cases and 103 controls) was conducted in a local suicide-attempt cohort. A sequence-based genome-wide association study (seqGWAS) (with whole-exome sequencing data from the Schizophrenia in African Xhosa (SAX) study, (n= 749 cases and 788 controls) was then performed using PLINK. Thereafter, the genetic correlation between suicide attempt and SCZ was assessed using LD Score (LDSC) regression utilizing the latest GWAS summary statistics from the Psychiatric Genetics Consortium (PGC) for both suicide attempt (Ncases= 43,871, Ncontrols= 915,024) and SCZ (Ncases= 76,755, Ncontrols= 243,649). Lastly, polygenic risk scoring was performed using PRS-CSx which allows for trans-ancestry analysis. Association testing was performed in the statistical environment, R. Results: None of the 18 genotyped variants were associated with suicide attempt in the test cohort. The variant rs75837205(p-value = 9.92×-09), located in an intergenic region on chromosome 9, showed genome-wide significance (p-value < 5×10-8). A positive genetic correlation (rg = 0.52, pvalue = 0.0001) between suicide attempt and SCZ was observed, but no association between suicide attempt-PRS and SCZ was detected after correcting for multiple testing. Discussion: The findings reported here reveal novel insights into the genetic architecture of suicide attempt and SCZ in the South African context. Results from this study confirm the genetic overlap between these two traits. This study may offer greater insight into the underlying biological mechanisms involved in suicide attempt and SCZ in the local AFR population. However, further studies with larger sample sizes, and appropriate measurements in populations of AFR ancestry are needed to validate these findings.
- ItemOpen AccessLow Rectovaginal and anovaginal fistula repair using a gracilis muscle flap at Groote Schuur Hospital(2026) Motlaleselelo, Pako; Nel, DanielIntroduction RVF is a severely debilitating condition with a significant impact on the patient's physical, social, and psychological well-being yet treatment is challenging fraught with high recurrence rates and absence of standardized treatment algorithms. Surgery remains the cornerstone of management despite the absence of a single surgical treatment considered to treat all RVF adequately. Gracilis flap has been used as an attractive option with high success and low complication rates. The body of literature regarding the application of the gracilis flap for addressing rectovaginal fistulas consists of fewer than 40 minor retrospective case series. Furthermore, there is a lack of local data assessing the effectiveness and usefulness of gracilis flaps for addressing RVF in patients from South Africa. Methods In this study, we are aiming to describe our experience in terms of safety and efficacy. After obtaining human research ethics committee approval, a retrospective review of all patients who underwent repair of rectovaginal or anovaginal fistula using gracilis muscle flap between January 2016 and December 2022 was undertaken. Data on patients' demographics, clinical presentation, fistula characteristics, and operative and surgical outcomes were obtained. Clinic follow-up notes were used to look at three months of recurrence after the gracilis flap repair and also three months after stoma closure. Results Over a period of 7 years from 2016 to 2022, six patients underwent retrograde gracilis muscle transposition flap. Patients' age ranged from 19 to 64 years. The main presenting symptoms were passing stool per-vagina. The underlying etiology was an obstetric injury in three patients (50%), foreign body in one patient, post-surgery for rectocele repair in one patient, and the last one of unknown etiology in HIV patient (Table 1). Three patients were found to have RVF with sphincter injury; one was repaired before she was referred to the pelvic floor clinic (patient 4) and the other two referred with concomitant sphincter injury with and without incontinence in patients 5 and 6 respectively. Patient 5 had simultaneous RVF gracilis flap and sphincter injury repair. Patient 6 had a staged procedure, where sphincter repair followed by sacral nerve stimulator was performed before the RVF gracilis 4 flap repair. All patients had previous repair once or twice with either simple repair or advancement flap repair (Table 2). All patients had a covering sigmoid loop colostomy either before or in the same setting with the RVF repair. In this series, the three months success rate was 100%, but both short- and long-term complications were reported in three patients, 50%. The short-term complications were SSI and gracilis flap incomplete necrosis that required debridement under general anaesthesia. Also, two patients developed a parastomal hernia. The mean time from RVF repair to loop colostomy closure was (12.1 months) ranged from 4 to 20 months. Two of the three patients who had stoma closure within one year, had an early closure because they developed a symptomatic parastomal hernia. There were no RVF recurrences reported up to three months after stoma closure (Table 3). Conclusion We concluded that the use of Gracilis flap resulted in very low rates of recurrences but stoma closure rates of 50% at one year thus proving a safe and effective treatment option in patients with complicated rectovaginal fistulas, in addition gracilis flap is an ideal option in patients who have had previous failed attempts at repair.
- ItemOpen AccessTrade liberalisation and wage inequality within the regions of South Africa(2026) Molokoane, Tshepo Norman; Mateane, LebogangThis study examines the relationship between trade liberalisation and wage inequality in South Africa's manufacturing sector over the period 1998-2017, using the Stolper-Samuelson theorem as a framework. In this study, we use the autoregressive distributed lag (ARDL) bounds testing technique to estimate the long-run relationship between relative prices, trade openness, labour productivity, human capital, regions, and skill premium. Our main findings show that trade liberalisation has contributed to an increase in wage inequality, predominantly through relative prices, in both the short and long run. We also find that trade openness explains the modest decline in wage inequality, particularly within the coastal region. Additionally, we observe a negative relationship between labour productivity and skill premium across both time frames. The results further reveal that human capital negatively impacts the skill premium but is statistically insignificant in the inland and inland core regions. Regional wage disparities significantly and positively influence the skill premium in the coastal region in the long run, and in the inland region in both the short and long run.
- ItemOpen AccessUnderstanding the post-implementation challenges of cloud ERP: An SAP S/4 HANA case(2026) Mohammed, Fawwaz; Seymour, LisaEnterprise Resource Planning (ERP) systems are critical in streamlining operations, improving data accuracy, and enhancing decision-making through centralised information. Globally, 50–60% of organisations utilise ERP systems, with large enterprises investing up to USD 10 million per implementation. Cloud computing has transformed the ERP landscape, offering greater flexibility, efficiency, and agility. However, despite these advantages, many organisations face significant postimplementation challenges, such as integration issues, user resistance, and data security concerns. These challenges hinder the realisation of expected benefits. Understanding these challenges is essential to ensuring the long-term success of cloud ERP initiatives. This study examined two large organisations that completed SAP S/4HANA Cloud implementations using different deployment models. This approach allowed a comparative analysis to answer the research question on post-implementation challenges of cloud ERP. Data was collected through a qualitative approach using semi-structured interviews. Furthermore, a six-step thematic analysis was used to analyse the data to explore patterns and themes. In addition, a coding matrix was used to explore relationships between those themes. Insights from the pre-implementation and implementation phases provided context for analysing post-implementation challenges. Furthermore, the study identified four key post-implementation challenges of cloud ERP: operational, management, organisational, and IT. The results revealed configuration limitations, integration complexity, and reporting constraints, particularly within SAP S/4HANA public cloud environments. Limited customisation and user resistance hindered adoption, while data control and authorisation concerns persisted. Despite these challenges, both organisations viewed the implementation as successful, supported by ongoing change management and training initiatives.
- ItemOpen AccessDescription of the growth, reproductive biology and feeding habits of the False Jacopever (Sebastes capensis)(2026) Mohamed, Taahir; Attwood, ColinThe genus Sebastes (rockfishes) is a group of viviparous marine scorpionfish represented by at least 110 species worldwide, of which Sebastes capensis (the false jacopever) is the only South African species. Historically, S. capensis has been confused with Helicolenus dactylopterus (the jacopever) and Sebastes oculatus (the Patagonian redfish), which has contributed to lack of reliable information on the species. To describe the life-history of this important reef fish on South Africa's west coast, biological data were extracted from 269 specimens collected by hook and line and used to describe the morphology, growth, reproduction, and feeding habits of the species. The length-weight models indicated hyper-allometric growth for female fish (W = 5.08 × 10–6 TL3.23), while that of males and combined sexes was determined to be isometric (W = 1.39 × 10–5 TL3.04 and W = 1.57 × 10–5 TL3.02, respectively). Fish ranged from 205 to 372 mm in length and 3 to 23 years old. The best-fit von Bertalanffy growth model for females was TL = 358.1 × (1 – e−0.105 (t + 5.70)), and that for males was TL = 355.4 × (1 – e−0.138 (t + 3.21)). Males dominated the sex ratio, outnumbering females by 2.68:1. Length at 50% maturity for female and male fish were estimated to be 251.2 mm (6 years) and 216.3 mm (4 years), respectively. Seasonal trends in the gonadosomatic index and the frequency of reproductively active fish point towards a parturition season extending from the start of winter into early spring. Copulation occurs mainly during late autumn. Evidence of sperm storage were found in the ovaries of females during the reproductive period. The presence of both eyed-larvae and unfertilised eggs inside the ovaries of pregnant fish points towards a multiple brooding reproductive strategy, with brood fecundity estimated to be between 40 000 and 100 000 embryos. Sebastes capensis is an opportunistic and generalist predator with a close association to the benthos, a characterization supported by its morphology and bright colouration. Sebastes capensis is a slow-growing and late-maturing rockfish, making the species potentially vulnerable to overfishing, particularly given its prevalence in catches of recreational and commercial boat fishers along South Africa's west coast.