Browsing by Author "Teshome, Beza"
Item Dissolution Enhancement of Albendazole Using Solid Dispersion Technique(Addis Ababa University, 2016-07) Teshome, Beza; Gebre-Mariam, Tsige(Professor); Feleke, Fitsum(PhD)Albendazole (ABZ) is a benzimidazol (BZD) derivative with broad spectrum of activity against human and animal helminth parasites. However, its poor water solubility gives rise to formulation problems and reduced bioavailability. These problems can be reduced by increasing the dissolution rate of the drug using different approaches such as solid dispersions (SDs). This study was designed to formulate ABZ loaded SDs with improved dissolution profiles. For this purpose, binary and ternary SDs were prepared by kneading and solvent evaporation methods using the hydrophilic carriers such as polyethylene glycol 4000 (PEG), polyvinyl pyrrolidone K-30 (PVP) and hydroxypropyl methylcellulose 5 cps (HPMC) and the surfactant polysorbate 80. To prepare binary SDs, the carriers were used in three drug: carrier proportions (1:0.5, 1:1, 1:2), where as in case of ternary SDs, polysorbate 80 was added at 0.1 proportion of the pure drug for all proportions of the carriers used. Physical mixtures (PMs) containing the above mentioned carriers were similarly prepared for comparison purpose. Fourier Transformer Infrared Spectroscopy (FTIR) studies of the samples stored for 2 months revealed interaction through hysdrogen bonding between the drug and the carriers. Differential Scanning Calorimetry (DSC) of the PMs and SDs indicated decreased crystallinity of the drug. Dissolution profiles of ABZ were remarkably improved from the binary and ternary SDs as well as from ternary PMs than the pure drug (4.50% within 60 min). The rate and extent of dissolution was significantly higher in the ternary systems than the binary systems (p < 0.5). Solvent evaporation method demonstrated the highest dissolution profile. The ternary SD of ABZ with PEG and polysorbate 80 at a ratio of 1:2:0.1 prepared with solvent evaporation technique showed the highest dissolution profile with 100% of the drug released within 60 min. The SDs with PEG showed higher dissolution profiles than with PVP in both the SDs prepared by kneading and solvent evaporation techniques. From the SDs prepared by kneading method, the highest drug release was observed with the carrier HPMC (88.8% of the drug being released with 60 min) followed by PEG (81.4%). In all the formulations the release of ABZ was shown to increase with increasing carrier proportions. XIII The prepared SDs were characterized for flow properties and compressibility. Tablets of selected SDs were prepared by direct compression method and evaluated for their quality attributes. The results revealed that the major factors that affect the SDs and tablet characteristics are carrier to drug ratio, the amount of microcrystalline cellulose (MCC) and compression force. Thus, 3 factors, two level (2 3) full factorial experimental design was selected to investigate the effects of the selected factors on the various responses such as flow property, compressibility and drug release in 10 min and 60 min. Accordingly, the various models describing the relationship of the selected variables were obtained using Design-Expert 9.0.6 software and the optimum area was determined. The optimal points for the responses were found to be 55.09% for amount of ABZ released within 10 min, 81.27% for amount of ABZ released within 30 min, 29.48° for angle of repose, 94.60 N for hardness and 0.62% for friability when the factors are set at compression force of 14.03 KN, carrier to drug ratio of 1.98 and concentration of MCC of 23.57%. The validity of obtained optimal point was confirmed experimentally. Evaluation of the optimized formulation showed successful formulation of ABZ SD tablets. The release profiles of the optimized tablet formulation were superior to marketed tablets. Thus, it can be concluded that the dissolution of ABZ is significantly enhanced by SD technique. Key Words: Albendazole; HPMC; Kneading; PEG; Physical mixture; Polysorbate 80; PVP; Solid dispersion; Solvent evaporationItem Magnitude and Associated Risk Factors Of Possible Fungal Infection Among HematoOncology Patients With Neutropenia at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia(Addis Abeba University, 2021-10) Teshome, Beza; Dr.Abebe, Workeabeba(MD, MPH); Dr.Hailu, Daniel (MD)Background A fungal infection represents a growing problem i n children with hematologic mali gnancies duri ng chemotherapy-induced neutropenia. Objectives: This study ai med to evaluate the magnitude of possible fungal infection among hemato-oncologic children admitted to the hospital between 2017 and 2021 in TASH, Ethiopia. Methods: Institution-based retrospective cross-sectional study reviewed the charts of 256 neutropenic patients at Ti kurAnbessa specialized hospital. Required data were collected using a questionnaire. The data were entered i nto a computer usi ng Excel and exported to Statistical Package for Social Sciences Version 25 for analysis. Binary logistic regression analysis assessed predicting factors associated with a fungal infection, and p-value <0.05 was considered statistically signi ficant. Results: Among 256, 152 were males, and most of the patients were in the age range of 5-10 years. In this study, the magnitude of fungal infection among haemato-oncology neutropenic patients was 31%. Among those patients diagnosed with a possible fungal infection, 56 (72%) ALL patients, 6 (7.7%) AML patients and 15 (19%) of NHL patients. Age, duration, and severity of neutropenia and prolonged use of steroids are significantl y associated factors. Conclusion: Our fi nding suggests a high rate of fungal infections in neutropenic ALL and AML patients. These results help i mprove the management of these patients. However, fur ther studies are needed.Item A Structure-Conduct-Performance Analysis of the Ethiopian Microfinance Industry(2014-06) Teshome, Beza; Amha, Wolday (PhD)The main objectives of this study are to analyze the Structure-Conduct-Performance of the microfinance industry and measure the level of competition. In order to achieve these objectives, both descriptive and econometric analyses were carried out. In the econometric analysis, a three-stage-least-squares (3SLS) estimation method was used to estimate a model comprising two equations, each representing the structure and performance of the industry, for a sample of fifteen MFIs for years 2003 to 2011. From the descriptive analysis, it was found that there is no form of collusion among MFIs in terms of their pricing strategies and that the sector is concentrated, with regional-government backed MFIs dominating the industry. However, competition exists between MFIs and banks in terms of saving mobilization. The findings from the econometric analysis revealed that MFI size, capital structure, average loan size and financial self-sufficiency significantly affect the market share of MFIs. Furthermore, average loan size and cost per borrower were found to significantly affect the performance of MFIs, whereas market share and yield on gross portfolio were found to have an insignificant effect on the financial performance of MFIs. The findings imply that in the microfinance industry, performance of MFIs affects market structure, while the structure of the market has an insignificant effect on market performance