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Secondary lymphedema is caused by damage to the lymphatic system from surgery, cancer treatment, infection, trauma, or obesity. This damage induces stresses such as oxidative stress and hypoxia in lymphatic tissue, impairing the lymphatic system. In response to damage, vascular endothelial growth factor C (VEGF-C) levels increase to induce lymphangiogenesis. Unfortunately, VEGF-C often fails to repair the lymphatic damage in lymphedema. The underlying mechanism contributing to lymphedema is not well understood. In this study, we found that surgery-induced tail lymphedema in a mouse model increased oxidative damage and cell death over 16 days. This corresponded with increased VEGF-C levels in mouse tail lymphedema tissue associated with macrophage infiltration. Similarly, in the plasma of patients with secondary lymphedema, we found a positive correlation between VEGF-C levels and redox imbalance. To determine the effect of oxidative stress in the presence or absence of VEGF-C, we found that hydrogen peroxide (H2O2) induced cell death in human dermal lymphatic endothelial cells (HDLECs), which was potentiated by VEGF-C. The cell death induced by VEGF-C and H2O2 in HDLECs was accompanied by increased reactive oxygen species (ROS) levels and a loss of mitochondrial membrane potential. Antioxidant pre-treatment rescued HDLECs from VEGF-C-induced cell death and decreased ROS under oxidative stress. As expected, VEGF-C increased the number of viable and proliferating HDLECs. However, upon H2O2 treatment, VEGF-C failed to increase either viable or proliferating cells. Since oxidative stress leads to DNA damage, we also determined whether VEGF-C treatment induces DNA damage in HDLECs undergoing oxidative stress. Indeed, DNA damage, detected in the form of gamma H2AX (γH2AX), was increased by VEGF-C under oxidative stress. The potentiation of oxidative stress damage induced by VEFG-C in HDLECs was associated with p53 activation. Finally, the inhibition of vascular endothelial growth factor receptor-3 (VEGFR-3) activation blocked VEGF-C-induced cell death following H2O2 treatment. These results indicate that VEGF-C further sensitizes lymphatic endothelial cells to oxidative stress by increasing ROS and DNA damage, potentially compromising lymphangiogenesis. [ABSTRACT FROM AUTHOR]

Experiential learning is touted as an effective way of imparting research skills. This suggests that master's students undergoing training in research psychology should be exposed to managing projects and supervising interdisciplinary research teams and projects before entering the workplace. The Department of Psychology and Department of Town and Regional Planning at a South African university developed a near-peer mentoring programme in which the psychology master's students mentored undergraduate urban planning students who were writing their final-year research reports. Focus group discussions with the psychology students about their experiences of the programme were analysed using phenomenography. The psychology students experienced their role as mentor in five hierarchical variations. The first four were seen as challenging, while the benefits were only experienced at the highest level of the hierarchy. Lessons learnt from the mentoring relationship that mirror certain workplace research skills are discussed followed by recommendations for improving the mentoring programme.

The 2010 Western Cape graduate destination survey utilised a sequential mixed-mode design in which an initial web survey was augmented with an equivalent telephonic survey. This article examines mode effect in the Western Cape survey in terms of overall effect size and the bearing it had on the main outcome of the study. Standardised residuals and Cramér's V are used to determine mode effect across two scenarios, a full sample vs. a subsample, and using two categorical questions with different numbers of response categories. Overall effect size appears to be small in the first question, but increases noticeably together with non-responses in the second question that has many more response categories. Web responses to alumni or graduate destination surveys can perhaps be augmented with telephonic responses if necessary, provided response categories are kept to a minimum, and interviewers are trained properly and monitored for possible interviewer misbehaviour. The benefit of obtaining larger samples should then also outweigh the benefit of using web surveys alone.

Current literature proposes several strategies for improving response rates to student evaluation surveys. Graduate destination surveys pose the difficulty of tracing graduates years later when their contact details may have changed. This article discusses the methodology of one such a survey to maximise response rates. Compiling a sample frame with reliable contact details was most important, but may require using additional sources of information other than university records. In hindsight, graduates should have been contacted prior to the survey to introduce it and stress its importance, while email and postal reminders appeared to have a limited effect on non-respondents. Due to varying response rates between participating universities, online responses were augmented with a call centre administering the survey telephonically to non-respondents. Although overall differences between online and telephonic responses appeared to be small, certain question items may need to be treated with caution when conducting telephonic surveys.

The South African workforce is characterised by racial, gender, occupational and sectoral unevenness in the distribution of skills, employment and training opportunities. This article considers how enterprise training in South Africa contributes to ameliorating, sustaining or exacerbating such inequalities. Using data from the National Skills Survey of 2003, it explains these features with reference to a tension between the distorted apartheid training legacy and the inherent unevenness of training-related policy implementation after 1994. Unevenness will be a feature of any national workplace training environment and is not necessarily a sign of dysfunction. In South Africa, unevenness in the pattern of access to training opportunities may reflect legitimate treatment of workers who were previously disadvantaged. (Contains 10 tables and 1 note.)

Context: Radiographic measurements on full-length lower limb views are the standard for lower limb deformity analysis. The published measurements of Paley et al.[1] on lower limb alignment are the gold standard, but were derived from small adult samples. There are no radiographic measurements reported exclusively of South African children. Aims: The study aimed to establish the normal values of lower limb alignment and joint orientation angles in South African children between 5 and 18 years old, at specific age intervals and to compare these measurements to the values as derived from Paley et al.[1] Settings and Design: A cross-sectional radiographic study including all 5--18-year-old children who underwent full-length anteroposterior radiographs between 2012 and 2020 was conducted. Subjects and Methods: Radiographic measurements were done as described by Paley. Differences in measurements obtained and those reported by Paley et al.[1] were compared. Results: A total of 190 patients (110 male; 80 female) with a mean age of 10.0 ± 3.3 years were included. The medial neck-shaft angle (MNSA), mechanical and anatomical lateral distal femoral angle (LDFA) and lateral distal tibia angle (LDTA) remained consistent throughout the age groups. Significant differences between Paley's published values and our cohort were observed for the median mechanical axis deviation (MAD), MNSA and medial proximal tibia angle(MPTA).[1] Conclusion: Significant differences were seen in the mean/median of our MAD, MNSA, and MPTA compared to Paley's work. Other measured values are comparable with previously published adult and pediatric populations. Using the acquired data, we were able to develop set values that could be the norm for pediatric joint orientation angles in the South African population. [ABSTRACT FROM AUTHOR]