Search

The prognosis of chronic myeloid leukemia (CML) on tyrosine kinase inhibitor (TKI) treatment is based on the quantification of BCR::ABL1 fusion gene transcript copy number, harmonized by an international scale (IS) based on TaqMan-based real-time quantitative PCR (qRT-PCR). In Ethiopia, as in most low- and middle-income countries (LMICs), access to standard diagnostic, follow-up, and prognostic tools is very limited, and it has been challenging to strictly follow international guidelines. This seriously compromises clinical outcome, despite the availability of TKIs through the Glivec International Patient Assistance Program (GIPAP). Multiplex PCR (mpx-PCR), conventionally regarded as a “screening tool,” offers a potential solution to this problem. A total of 219 samples from confirmed CML patients were assayed. In reference to qRT-PCR, the AUC of ROC curve for mpx-PCR was 0.983 (95% CI: 0.957 to 0.997). At the optimum cut-off value, equivalent to BCR::ABL1 (IS) transcript copy number of 0.6%, the specificity and sensitivity were 93% and 95%, respectively, with 94% accuracy. Albeit the sensitivity and accuracy of mpx-PCR decrease below the optimum cutoff of 0.6% (IS), the specificity at 0.1% (IS) was 100%, making it an attractive means to rule-out relapse and drug non-adherence at later stages of treatment, which is particularly an issue in a low income setting. We conclude that the relative simplicity and low cost of mpx-PCR and prognostic relevant cutoff values (0.1–0.6% IS) should allow its use in peripheral clinics and thus maximize the positive impact of TKIs made available through GIPAP in most LMICs.

Educational partnerships between academic health sciences centers in high- and low-resource settings are often formed as attempts to address health care disparities. In this Perspective, the authors describe the Toronto Addis Ababa Academic Collaboration (TAAAC), an educational partnership between the University of Toronto and Addis Ababa University. The TAAAC model was designed to help address an urgent need for increased university faculty to teach in the massive expansion of universities in Ethiopia. As TAAAC has developed and expanded, faculty at both institutions have recognized that the need to understand contextual factors and to have clarity about funding, ownership, expertise, and control are essential elements of these types of collaborative initiatives. In describing the TAAAC model, the authors aim to contribute to wider conversations and deeper theoretical understandings about these issues.

In this chapter, observers are designed for a class of nonlinear interconnected systems with uncertain TVPs, in which both the isolated subsystems and the interconnections are nonlinear. The designed observers are variable structure interconnected systems, but may not result in sliding motion. Under the condition that the difference between the unknown TVPs and the corresponding uncertain nominal values are bounded by constants, adaptive updating laws are proposed to estimate the parameters. The persistence of excitation conditions is not required. A set of sufficient conditions are proposed such that the error dynamics formed by the system states and the designed observers are asymptotically stable, while the parameters’ estimation errors are uniformly, ultimately bounded using the LaSalle’s theorem. The results obtained are applied to a coupled inverted pendulum system, and simulation results are presented to demonstrate the effectiveness and feasibility of the developed results. The main contribution includes: (i) Both the interconnections and isolated subsystems take nonlinear forms. (ii) The unknown parameters considered in the system are time varying, and the corresponding nominal values are not required to be known. (iii) The asymptotic convergence of the observation error between the states of the considered systems and the states of the designed observers is guaranteed; while the estimate errors of the TVPs are uniformly, ultimately bounded.

Non secretary multiple myeloma (NSMM) is a rare variant of multiple myeloma (MM) with similar clinical and radiologic picture but without monoclonal gammopathy in the serum or urine. A non-secretary type multiple myeloma was diagnosed clinically and radiologically in a young Ethiopian presenting with low back pain. He had a diffuse osteopenia of the iliac bone, punched out lytic skull lesions and plasmacytosis on the bone marrow aspiration. But the serum electrophoresis of the patient did not show M component. Both the variant and the age of the patient are unique features observed in this case report.