Browsing by Author "Khumalo, Nonhlanhla"
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- ItemOpen AccessBioenergetic Evaluation of Site-specific Keloid and FKN Fibroblasts(2019) Chalwa, Temwani; Khumalo, Nonhlanhla; Bayat, Ardeshir; Lebeko, MaribanyanaExcessive scarring due to fibrosis from aberrant wound healing can lead to conditions such as Keloids or Folliculitis Keloidalis Nuchae (FKN). These fibroproliferative growths pose therapeutic challenges due to their complex aetiology that has been linked to multiple genetic and environmental factors, with frequent reoccurrence following therapy. Owing to reports on an increase in ATP and Fibroblast Activation Protein-1α production in keloids, the aim of this study was to investigate whether the disease phenotypes were linked to bioenergetic changes at a cellular level in these two conditions. Patient-derived tissue biopsies were used for fibroblast cell culture models, in which cell analysis was carried out to assess phenotype and different parameters of bioenergetic cellular behaviour. In addition to FKN and the intra- and peri-lesional Keloid patient fibroblasts, normal skin and non-hypertrophic (normo-trophic) scar fibroblasts were used as negative controls. The results show statistically significant and variable growth dynamics with increased proliferation and migration in keloid fibroblasts, while FKN fibroblasts showed a statistically significant increase in proliferation but had a similar migration profile to controls. The results further show that there is a statistically significant metabolic switch towards aerobic glycolysis in the fibroblasts from the disease conditions. During functional measurement of mitochondrial parameters, an increase in oxidative phosphorylation was exhibited in the disease conditions indicating their mitochondria were still functional. An increase in basal glycolysis with a concomitant increase in the cellular maximum glycolytic capacity was also demonstrated. Furthermore, protein analysis showed an upregulation in the expression of Fibroblast Activation Protein-1α in fibroblasts from both disease conditions This study begins to give novel insight into the bioenergetics of normal scars and scarring conditions such as FKN and, adds to the knowledge on the heterogeneity of fibroblasts derived from specific lesional sites within Keloids. These findings suggest that Keloids and FKN have a switch to a metabolic phenotype of aerobic glycolysis. This increase in glycolytic flux potentially proposes glycolytic inhibitors as a mechanistic basis for the treatment of these conditions.
- ItemOpen AccessBlood and virus detection on barber hair clippers(2019) Spengane, Zandile Namhla Elizabeth; Khumalo, Nonhlanhla; Ngwanya, Mzudumile RBackground: Bleeding from the popular clean-shave ‘chiskop’ haircut was recently reported as prevalent in South Africa (SA), a country with 6.9 million HIV-infected people. Objectives. To investigate the prevalence of barber hair clipper contamination with blood and HIV and hepatitis B viruses. Methods: Fifty barbers from three townships in Cape Town, SA, were invited to participate. One clipper from each barber was collected immediately after it had been used for a cleanshave haircut. Each clipper was rinsed with phosphate-buffered saline and then submerged in viral medium. The polymerase chain reaction (PCR) was used to identify the bloodspecific RNA marker haemoglobin beta (HBB), hepatitis B virus (HBV) and HIV. Results: The clean-shave haircut was the most common haircut requested by clients (78%). Of the clippers collected, 42% were positive for HBB, confirming detection of blood, none were positive for HIV, and 4 (8%) were positive for HBV. Two clippers (clippers 16 and 20) were positive on qualitative HBV PCR. HBV DNA from clipper 16 clustered with genotype A sequences from SA, India, Brazil and Martinique, while clipper 20 clustered with SA genotype D sequences. The clipper 20 sequence was identical to a subtype D sequence (GenBank accession AY233291) from Gauteng, SA. Conclusion: This study confirms that there is significant contamination of barber hair clippers with blood and blood-borne viruses. Hepatitis B was detected with enough DNA copies to pose a risk of transmitting infection. Although HIV was not detected in this small study, the risk of transmission should be quantified. Further studies to investigate barber clipper sterilization practices and whether the clean-shave hairstyle is an independent risk factor for HIV, HBV and hepatitis C virus infections are warranted. Public education on individual clipper ownership (as is the case with a toothbrush) should be advocated for clean-shave and blade-fade haircuts.
- ItemOpen AccessFolliculitis keloidallis nuchae severity score: development and reliability assessment(2020) Nyika, Dennias Toderai; Khumalo, Nonhlanhla; Isaacs, ThurayaBackground: Folliculitis keloidalis nuchae (FKN) is a chronic inflammatory condition that targets the hair follicle, leading to keloidal scarring and alopecia. The absence of a severity scoring tool for FKN limits objective assessment of disease progression and response to treatment. Objectives: To develop and test the reliability of a severity scoring tool for FKN. Methods: The tool was developed based on lesion type, number, size and distribution on the scalp. An initial pilot period with 2 assessors was followed by the main study that used 78 anonymised and standardised clinical photographs of the back of the scalp. The participants were selected from an ongoing case control study of FKN. The assessors could allocate disease severity in one of 14 categories (with/without inflammation). However, inflammation (especially erythema) can be missed in photographs of pigmented skin. Thus, two groups of analysis were conducted first with all 14 and again with 8 categories (i.e. excluding inflammation). Assessors were 4 dermatology consultants and 7 registrars, who all independently scored the same anonymised and standardised photographs on two separate occasions, 2 weeks apart. Results: Inter-observer standard errors were higher with the 14-category compared to the 8- category analysis for both consultants and registrars. The intraclass correlation coefficient for registrars improved from poor [0.46 (0.36 -0.56)] to good [0.74 (0.68- 0.80)] with 14 compared to 8-categories, but stayed the same for consultants [0.82 (0.76 – 0.88) versus 0.81 (0.75 – 0.87)]. Limitations of the study were the use of clinical photographs instead of live participants and the problem that the signs of inflammation may be particularly difficult to judge in pigmented skin. Conclusion: We developed a severity scoring tool with poor to good reliability which also highlighted the difficulty of perceiving inflammation from clinical photographs. This improved with the seniority of the observer. The 8-category analysis has good reliability for clinical photographs for both junior and senior staff. For live patient care and clinical trials the 14-category version is likely to be more useful, but requires validation.
- ItemOpen AccessHuman T cell lymphotropic virus type 1- associated infective dermatitis in KwaZulu Natal, South Africa(BioMed Central Ltd, 2013) Hlela, Carol; Graham, Natalie; Bhigjee, Ahmed; Taylor, Graham; Khumalo, Nonhlanhla; Mosam, AnisaBACKGROUND: The Human T cell lymphotropic virus type 1 (HTLV-1)-associated infective dermatitis (IDH), is a chronic relapsing dermatitis which usually presents in children older than 2years. A total of 300 cases have been reported worldwide (Latin America, the Caribbean and only 5 from Senegal). Neither IDH, nor its complications have been reported from the rest of Africa. We aimed to examine the clinical and aetiological characteristics of IDH in a cohort of South African children. METHODS: Attendees at the dermatology clinic at King Edward VIII Hospital, Durban underwent clinical examination. After obtaining consent those suspected of IDH had specimens taken for blood counts, immunoglobulins, serum protein electrophoresis, viral studies (including genotyping), skin swabs and stool examinations. RESULTS: Nineteen of 60 suspected cases recruited over 3years met the diagnostic criteria for IDH. The male-to-female ratio was 1:2; mean age 8years (range 0.7 to 15). Dermatitis mostly affected the scalp (78.9%) and axilla (73.7%); fewer children had nasal crusting (47.4%). Mean Ig A, IgG and IgM were raised, at 3.52g/l, 22.6g/l and 1.38g/l, respectively. The median CD4 cell count was 1958 cells/mm3. Viral genotyping of all tested samples were positive for the Cosmopolitan, Subtype A (HTLV-1a). CONCLUSIONS: IDH is a distinct entity which also affects South Africans. Our patients were older at presentation and the majority did not present with nasal crusting as has been described in other countries.
- ItemRestrictedInterdependence between geometric, tensile and chemical bond behaviours of untreated hair fibres(2020) Cloete, Elsabe; Ngoepe, Malebogo; Khumalo, NonhlanhlaTo date, an accurate understanding of the dynamics between the fibre's inherent geometric, mechanical and biological characteristics is deficient, affecting the reliability and robustness of hair data. There is also insufficient scientific clarity on the behaviour of curly hair, as most of the conclusions have been drawn from studies focusing on straight fibres. This research project aimed at gaining a more accurate understanding of the interrelationships between fibre curliness, strength and chemical bonding. In the current understanding of hair mechanics, curly fibres are considered to have a lower tensile strength than straight fibres. Furthermore, the current understanding of hair fibres does not associate hydrogen bonding with fibre shape. During experimentation, inadvertent observations suggested that current tensile methods ignore an important component of hair strength in curly fibres, and that hydrogen bonding supports fibre curliness. Intensive scrutiny of these observations led to fundamental contributions to the understanding of curly hair. Research tools included tensile, geometric, image, (FTIR) spectroscopic assessments, regression modelling and multivariate statistical analysis. Through this research, the role of hydrogen bonding in fibre curliness has been established. A theory is presented about extraordinary hydrogen bonds and the existence of hydrogen bond networks across the fibre matrix of curly hair. The theory has been substantiated experimentally via FTIR and weight measurements. The research also established the importance of the preelastic tensile region for curly fibres. It was clearly demonstrated that tensile strength of hair fibres is not only dependent on Young's modulus, but also on the fibre's inherent viscoelasticity, which appears to be important in curly fibres but becomes negligible with loss of curl. A model, developed from experimental observations and insights from similar biological fibres, is also presented. The model gives insights into ultrastructural changes at the early onset of fibre elongation. It also demonstrates the association between viscoelasticity and hydrogen bond networks. Taking this into consideration, a constitutive equation, developed to determine hair fibre strength accurately, is also presented in this work. This work does not replace current fibre curvature theories, but provides additional insights into hair shape, and therefore presents a fundamental contribution to curvature in human hair. It also highlights the shortcomings of current instrumentation methods that contribute to inaccurate conclusions regarding the strength of curly fibres.
- ItemOpen AccessThe use of hair detect (and monitor) chronic hyperglycaemia(2018) da Silva, Sian-Ailin; Van Wyk, Jennifer; Khumalo, NonhlanhlaBackground: Diabetes mellitus is a major public health problem resulting in about 5 million deaths per year. This metabolic disorder is characterized by hyperglycaemia, which results in debilitating and life-threatening complications. It is, therefore, vital for diabetics to monitor and control their blood glucose levels in order to keep them below 7mmol/L while fasting and below 9mmol/L after meals. Chronic estimates of glucose control of 8-12 weeks are obtained using glycated haemoglobin A1 (HbA1c). Non-invasive, less expensive methods of monitoring long term glycaemic control may be useful. Since scalp hair consists of about 80% protein, which is subject to non-enzymatic glycation, and growing hair has a rich blood supply exposing it to free glucose, it is likely that hair can be used as an alternative substrate for monitoring chronic hyperglycaemia. Subjects and Methods: Scalp hair and a blood samples (for HbA1c) were collected from 46 diabetic and 46 healthy control subjects. There were 26 diabetic adults (30-70 years), recruited from the outpatient clinic at Groote Schuur hospital and 20 children (7-18 years) recruited from the diabetic clinic at the Red Cross children's hospital. There were 29 healthy control adults (26-65 years) and 17 children (7- 17 years) recruited from the Groote Schuur and Red Cross hospitals respectively. History of chemical hair treatment was recorded for each participant. Hair samples were washed using 1% sodium dodecyl sulphate and analysed using Fourier transform infrared- attenuated total reflection (ATR-FTIR) spectroscopy. Spectra were analysed using statistical software (SIMCA, Umetrics) to determine whether the hair of diabetics was distinguishable from hair of healthy controls as well as whether spectra correlated with HbA1c levels of participants. Hair amino acid concentrations were also analysed as it is known that circulating amino acid concentrations are altered in people with diabetes. Results and discussion: The Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) models between spectra obtained from hair of diabetic participants and spectraobtained from control hair show good separation and predictive ability. When ATR-FTIR spectra were analysed in four groups: children with natural hair, adults with natural hair, adults with dyed hair and adults with relaxed hair, the models yielded predictive abilities (Q2(cum)) ranging from 0.753 to 0.85 and classification abilities ranging from 97.97 to 100%. This demonstrated excellent separation and predictive ability for controls vs. diabetics. Partial least squares (PLS) revealed a good correlation between hair FTIR spectra and participant HbA1c levels (R2 ranging between 0.8067 and 0.9296). These results demonstrated the possibility to use ATR-FTIR alongside multivariate data analysis to detect hyperglycaemia and monitor blood glucose levels via prediction of HbA1c levels from the hair spectra. Amino acid analysis supported the OPLS-DA classifications, as the largest differences were seen between age and chemically treated hair groups. Amino acid results reinforced the necessity to classify spectra into groups in order to distinguish between hair spectra from diabetics or controls, as well as to predict HbA1c. Twelve amino acids (Asp, Glu, Pro, Gly, Met, Ile, His, Lys, Arg, Amm, Cys, Leu) were significantly different between hair from adults and children, eight amino acids (Ala, Cys, Val, Met, Lys, Amm, Ser, Tyr) were statistically significantly different between natural and dyed hair and only up to four amino acids (Gly, Val, Met, Ile in children or Val, Phe, Amm, Arg in adults) were significantly different between diabetic and control groups. Conclusion: There is a need for non-invasive means of monitoring chronic hyperglycaemia. This study demonstrated the ability to distinguish between the hair of diabetics and controls as well as the ability to predict HbA1c levels from hair using ATR-FTIR. However, factors such as age and chemical treatment, which affect the chemical properties of hair, like amino acid levels, should be considered first. This would lead to promising prospects for long term blood glucose monitoring, due to the ability to estimate hair growth rate, and greater insights into the timing and development of diabetic complications. ATR-FTIR relatively simple to use, requires minimal sample preparation and does not require the use of expensive consumables. This technology could, potentially, be adapted into a primary health point of care or home screening or monitoring device for long-term hyperglycaemia, which would assist in early detection and preventing the progression of debilitating complications.