3. Electronic Theses and Dissertations (ETDs) - All submissions
Permanent URI for this communityhttps://wiredspace.wits.ac.za/handle/10539/45
Browse
2 results
Search Results
Item The sensitivity of bank credit risk indicators to macroeconomic variables(2016) Thwala, Cyprian McwayizeniThis study uses a dynamic panel data method to examine the sensitivity of non-performing loans (NPLs) and bank capital buffer (BCB) to macroeconomic variables. This approach is motivated by the hypothesis that says macroeconomic variables have an effect on the bank’s balance sheet, and this effect varies across developed and emerging economies. The results show that NPLs are sensitive to GDP growth, interest rate, public debt, sovereign debt and unemployment in developed economies. However, NPLs are sensitive to GDP growth, exchange rate, interest rate, sovereign debt, unemployment and volume of imports in emerging economies. Public debt is not statistically significant in explaining the sensitivity of NPLs in emerging economies. Similarly, exchange rate and volume of imports have no significant influence on NPLs in developed economies. In relation to the BCB we find GDP growth, exchange rate, interest rate, sovereign debt, unemployment and volume of imports as significant macroeconomic variables driving the sensitivity of capital buffer in emerging economies. Conversely, interest rate, sovereign debt and unemployment are macroeconomic variables responsible for the sensitivity of the buffer in developed economies. GDP growth, exchange rate and volume of imports have no significant influence. Considering the liquidity risk imposed to the banks’ balance sheet by this set of macroeconomic variables. It seems plausible that their dynamics should be given attention when conceiving any policy mix to cope with credit expansion. Without such exercise, the goal of financial stability in the global banking system will be difficult to achieve.Item Association between coagulation factor levels, cytokine profiles, clinical manifestations and genotypic features in factor X deficiency(2011-03-25) Thwala, Cyprian McwayizeniFactor X deficiency is a rare bleeding disorder with an incidence of one in a million in the general population. Patients with the severe form of factor X deficiency suffer from serious bleeds occurring mainly into the joints and the muscle. In the two factor X deficient families currently looked after at the Haemophilia Comprehensive Care Centre, there are definite differences in the bleeding tendencies between and within family members. We hypothesize the differences in genetic mutations and the influence of cytokines to be responsible for these bleeding variabilities. These factors were explored in our study. The study population included a total of fourteen members of the two families with factor X deficiency. Blood for factor X measurement, cytokine studies and genetic studies was collected in the Haemophilia Comprehensive Care Centre of the Charlotte Maxeke Johannesburg Academic Hospital. Each blood was processed according to the test to be performed. Factor X activity levels were measured using the factor X assay, and the information on each patient’s bleeding episodes was obtained from the Haemophiliac Clinic database. Cytokines were analyzed in all patients using the ELISA kits from Biosource. Factor X gene was amplified using PCR and sequenced with Spectrumedix SCE 2410. iv For cytokine studies, high levels of IL-1beta and TNF-alpha were observed in frequent bleeding patients compared to infrequent bleeders. These cytokines are known to be involved in acute inflammatory process leading to cellular infiltrate and joint swelling. This results in synovitis and the creation of massive joint bleeding. The low levels of IL-1beta and TNF-alpha detected in infrequent bleeding patients appear to be related to the high levels of IL-1Ra and IL-10. These anti-inflammatory cytokines are known to inhibit the inflammatory synovitis and lessen the severity of joint bleeding. For genetic studies, differences were observed between the amino acid sequence of the three frequent bleeding patients and the consensus. In addition, a novel mutation Cys350Phe was detected in two of these patients. This mutation is characterized by very low factor X levels which sometimes are not detectable in circulation. The substituted cystine is known to cause defect in the substrate binding, leading to the lost of enzyme activity. From these findings we have concluded that the origin of the heterogeneity of bleeding in factor X deficiency is multifactorial, cytokines and genetic mutations seems to have a role in determining the clinical manifestations of the factor X deficient patients.