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Plasmodium malariae and Plasmodium ovale infections and their association with common red blood cell polymorphisms in a highly endemic area of Uganda
No full textBackground
Plasmodium ovale and Plasmodium malariae infections are scarcely studied in sub-Saharan Africa, where the Plasmodium falciparum species predominates. The objective of this study is to investigate the prevalence of P. ovale and P. malariae infections and their relationship with common red blood cell polymorphisms in a cohort of 509 individuals from Uganda.
Methods
Three cross-sectional surveys were conducted in individuals of 1–10 and >20 y of age from the Apac district at baseline and 6 and 16 weeks after drug treatment. Malaria infections were assessed by polymerase chain reaction and genotyping was performed for the sickle-cell allele, α-thalassaemia and glucose-6-phosphate dehydrogenase.
Results
At baseline, the prevalence of infection was 7.5%, 12.6% and 57.4% for P. ovale, P. malariae and P. falciparum species, respectively. Co-infections were present in 14.1% of individuals, all including P. falciparum parasites. In children 1–5 y of age, the prevalence of P. ovale mono-infections increased significantly from 1.7% to 7.3% over time (p=0.004) while the prevalence of P. malariae and P. falciparum infections declined significantly during this study. After adjusting for confounding and multiple testing, only α-thalassaemia had a statistically significant increase in the odds of P. falciparum infections (odds ratio 1.93 [95% confidence interval 1.26 to 2.94]).
Conclusions
Common red blood cell polymorphisms do not show strong effects on mild Plasmodium infections in this Ugandan population. To understand the extent of this result, similar studies should be carried out in other populations using larger cohorts
Promoting Competence-Based Learning and Assessment Through Innovative Use of Electronic Portfolios
No full textThis chapter focuses on how innovative use of electronic portfolios (e-portfolios) can contribute towards meeting the needs of 21st century learners by promoting competence-based learning and assessment. The author explores various strategies and functionalities of e-portfolio application in higher education. Further, fundamental issues that relate to successful implementation of student academic e-portfolios are examined. Specifically, the relevance of congruent theoretical perspectives and teacher's involvement in the process of e-portfolio development are articulated among other key issues. Based on the emergent perspectives elucidated through this chapter, best practices to inform innovative and effective uses of e-portfolios are identified. The chapter illuminates how the effective use of e-portfolio can promote meaningful learning experiences and development of core competences including interactive collaboration, creativity, critical thinking, digital literacy, problem solving and self-efficacy
The role of monitoring and evaluation system in promoting performance of Non-Governmental Organizations in Juba County, South Sudan
Get PDFThis study did set to understand the role of M&E system in promoting performance of
NGO’s in Juba County, South Sudan. Monitoring and evaluation system plays paramount
role in promoting performance of non-governmental organizations. In South Sudan, NGO’s
allocates 5% to 10% of project budgets for monitoring and evaluation activities with the
purpose of promoting their performance. However, little progress has been made in this
regard in Juba County of South Sudan. The study was guided by four objectives; to assess
the influence of monitoring and Evaluation system in promoting performance of nongovernmental
organizations; to determine the influence of evaluation system in promoting
performance of non-governmental organizations; to assess the influence of participatory
monitoring and evaluation in promoting performance of non-governmental organizations; to
examine the importance of monitoring and evaluation department in promoting performance
of non-governmental organizations. To address the objectives, key informant interviews and
semi-structured questionnaires were used to collect data. The study assumes that the findings
would benefit different stakeholders i.e. NGO staff, students, researchers and scholars. The
study targeted ten (10) NGOs which were purposively sampled i.e. 5 NGO’s with M&E
system and 5 NGO’s without M&E system. Quantitative data were analyzed by SPSS
Version 21 and qualitative data were analyzed using descriptive narrative log. The research
findings and analysis were presented in bar charts, graphs, frequency tables, percentages and
narrative logs. Study findings show that non-governmental organizations with functional
monitoring and evaluation system have high chances for better performance compared to
non-governmental organizations without monitoring and evaluation system as well as nongovernmental
organizations with weak monitoring and evaluation system. The study
findings revealed that some non-governmental organizations without monitoring and
evaluation system have better performance due to consultant services they hired to provide
external monitoring and evaluation support. However it was very costly for those nongovernmental
organizations to maintain the consultants for a long time within the nongovernmental
organizations. Further the study show that non-governmental organizations
without monitoring and evaluation department were spending a lot of funds on hiring
consultants for baseline, mid-term evaluation and end line evaluation studies of their
projects. Based on the findings above, the study concludes that having a functional
Monitoring and Evaluation system with an NGO strengthens its performance. The study thus
recommends that non-governmental organizations without monitoring and evaluation
system should initiate it to avoid over spending on hiring consultants who are very costly to
maintain for a long time
PfMSA180 is a novel Plasmodium falciparum vaccine antigen that interacts with human erythrocyte integrin associated protein (CD47)
No full textMalaria symptoms and pathology are initiated by invasion of host erythrocytes by Plasmodium merozoites in a complex process that involves interactions between parasite and host erythrocyte proteins. Erythrocyte invasion presents attractive targets for malaria vaccine and drug development. Recently it was observed that antibodies against PfMSA180 (PF3D7_1014100) are associated with protection from symptomatic malaria, suggesting that this protein is a target of naturally acquired protective antibodies. Here we characterize PfMSA180, a ~170 kDa merozoite surface antigen that is potentially involved in erythrocyte invasion. PfMSA180 synthesized by the wheat germ cell-free system was used to raise antibodies in rabbits. Growth inhibition assays revealed that parasite invasion is inhibited by antibodies to the PfMSA180 C-terminal region, which contains an erythrocyte-binding domain. Surface plasmon resonance analysis showed that PfMSA180 specifically interacts with human erythrocyte integrin associated protein (CD47), suggesting that PfMSA180 plays a role during merozoite invasion of erythrocytes. Polymorphism analysis revealed that pfmsa180 is highly conserved among field isolates. We show that naturally acquired PfMSA180-specific antibodies responses are associated with protective immunity in a malaria-exposed Thai population. In sum, the data presented here supports further evaluation of the conserved erythrocyte-binding C-terminal region of PfMSA180 as an asexual blood-stage malaria vaccine candidate
The role of 8-quinolinyl moieties in tuning the reactivity of palladium(II) complexes: a kinetic and mechanistic study
No full textThe rate and mechanism of chloride substitution from Pd(II) complexes, chlorobis-(2-pyridylmethyl)aminepalladium(II), 1, chloro-8-[(2-pyridylmethyl)amino]quinolinepalladium(II), 2, chloro-N-(2-pyridinylmethylene)-8-quinolinaminepalladium(II), 3, and chlorobis(8-quinolinyl)aminepalladium(II), 4, are reported. The labile chloride was substituted from the complexes by thiourea nucleophiles viz, thiourea (Tu), N,N′-dimethylthiourea (Dmtu) and N,N,N′,N′-tetramethylthiourea (Tmtu). The reactions were monitored under pseudo-first-order conditions in methanol using stopped-flow spectrophotometry as a function of concentration and temperature. All the reactions obeyed the rate law kobs = k2[Nu] following the order 1 > 3 > 2 > 4 with 4 exhibiting the slowest rate of substitution due to the stronger σ-donor effect of 8-quinolyl moiety of the coordinated ligand, which makes the Pd center more electron-rich. This slows the nucleophilic attack by the nucleophiles. The values of the thermodynamic parameters (ΔH# and ΔS#) support an associative substitution mechanism. The trends in the DFT calculated data support the experimentally observed order of the reactivity of the complexes
Meeting Higher Education Expectations in the Digital Age and Reliability of Assessment in E-Learning Settings
No full textAs online and blended learning increasingly become common, higher educators and researchers need to rethink fundamental issues of teaching, learning, and assessment in these non-traditional spaces. Fundamental issues of assessment and in particular reliability have not been well understood despite proliferation of e-learning in higher education. The chapter begins with a justification of the need to reconceptualize assessment and associated fundamental issues in e-learning settings. The author further articulates the distinction between reliability within the context of assessment for learning (formative assessment) and assessment of learning (summative assessment). The core characteristics of reliability are critically examined and exemplified using research insights in relation to how achievement of these characteristics enhances reliability and by implication validity of assessment. The identified characteristics include opportunities for explicit learning goals and shared meaning, documentation, and monitoring evidence of learning; and multiple sources of evidence of learning and multi-dimensional perspectives. Finally, conclusions and recommendations are offered
The Effects of Acute Multisession Bifrontal Transcranial Direct Current Stimulation on Intractable Tinnitus and comorbid depression and anxiety: A Study Protocol for Randomized Controlled Trial
Get PDFTranscranial Direct Current Stimulation (tDCS) may exert therapeutic effects on tinnitus. This Randomized Control Trial (RCT) with double blind and placebo design investigates the potential therapeutic effects of Transcranial Direct Current Stimulation on chronic and intractable tinnitus using a new protocol. Acute repeated sessions of bifrontal Transcranial Direct Current Stimulation with two months follow up will be used for treatment of tinnitus symptoms and comorbid anxiety and depression. To best of our knowledge, this is the first randomized control trial investigating the effects of acute Transcranial Direct Current Stimulation exposure in intractable tinnitus.Methods: This randomized control trial is conducted as double blinded placebo controlled with parallel group in patients with chronic intractable tinnitus. The patients will be randomly divided into two real or intervention and sham or placebo Transcranial Direct Current Stimulation. The real Transcranial Direct Current Stimulation group will receive two sessions per day with intersession interval of 6 hours for 5 consecutive days per week for one week (total 10 sessions). The Transcranial Direct Current Stimulation parameters include bifrontal (anode/cathode over right/left dorsolateral prefrontal cortex (DLPFC) 2 mA current (current density 57.1 μA/cm2), each session 20 min through 35 cm2 electrodes. The sham group will receive the same Transcranial Direct Current Stimulation parameters and electrode montage and after 30 seconds, the device will be turned off without informing the patient. The primary outcome is the score of Tinnitus Handicap Inventory (THI) measured at baseline (pre-intervention) and post-intervention at immediately, one, and two months after last session. The secondary outcomes are tinnitus loudness, tinnitus distress, depression, and anxiety scores. The tinnitus loudness and distress are measured with a 0-10 Numerical Rating Scale (NRS) pre-intervention and post-intervention at immediately, one hour, one week, one, and two months after the last Transcranial Direct Current Stimulation session. Beck Depression (BDI-II) and Anxiety Inventories (BAI) is respectively used for measuring depression and anxiety score pre- and post-intervention. Finally, the adverse effects of and tolerability to Transcranial Direct Current Stimulation will be assessed in both real and sham groups using customized questionnaire.Discussion: To the best of our knowledge this is the first RCT investigating the effects of daily two sessions of Transcranial Direct Current Stimulation in repeated regime on chronic intractable tinnitus symptoms, depression, anxiety, and adverse effects in a long term study of two months follow-up
The N-Terminal Region of Plasmodium falciparum MSP10 Is a Target of Protective Antibodies in Malaria and Is Important for PfGAMA/PfMSP10 Interaction
No full textClinical manifestation of malaria is mainly due to intra-erythrocytic development of Plasmodium parasites. Plasmodium falciparum merozoites, the invasive form of the blood-stage parasite, invade human erythrocytes in a complex but rapid process. This multi-step progression involves interactions between parasite and human host proteins. Here we show that antibodies against a vaccine antigen, PfGAMA, co-immunoprecipitate with PfMSP10. This interaction was validated as direct by surface plasmon resonance analysis. We then demonstrate that antibodies against PfMSP10 have growth inhibitory activity against cultured parasites, with the region PfMSP10 R1 that is critical for its interaction with PfGAMA being the key target. We also observe that the PfMSP10 R1 region is highly conserved among African field isolates. Lastly, we show that high levels of antibodies against PfMSP10 R1 associate with reduced risk to clinical malaria in children resident in a malaria endemic region in northern Uganda. Put together, these findings provide for the first time the functional context of the important role of PfGAMA/PfMSP10 interaction in erythrocyte invasion and unveil a novel asexual blood-stage malaria vaccine target for attenuating P. falciparum merozoite invasion