Prevalence of potential mediators of artemisinin resistance in African isolates of Plasmodium falciparum

BACKGROUND

The devastating public health impact of malaria has prompted the need for effective interventions. Malaria control gained traction after the introduction of artemisinin-based combination therapy (ACT). However, the emergence of artemisinin (ART) partial resistance in Southeast Asia and emerging reports of delayed parasite sensitivity to ACT in African parasites signal a gradual trend towards treatment failure. Monitoring the prevalence of mutations associated with artemisinin resistance in African populations is necessary to stop resistance in its tracks. Mutations in Plasmodium falciparum genes pfk13, pfcoronin and pfatpase6 have been linked with ART partial resistance.

METHODS

Findings from published research articles on the prevalence of pfk13, pfcoronin and pfatpase6 polymorphisms in Africa were collated. PubMed, Embase and Google Scholar were searched for relevant articles reporting polymorphisms in these genes across Africa from 2014 to August 2021, for pfk13 and pfcoronin. For pfatpase6, relevant articles between 2003 and August 2021 were retrieved.

RESULTS

Eighty-seven studies passed the inclusion criteria for this analysis and reported 742 single nucleotide polymorphisms in 37,864 P. falciparum isolates from 29 African countries. Five validated-pfk13 partial resistance markers were identified in Africa: R561H in Rwanda and Tanzania, M476I in Tanzania, F446I in Mali, C580Y in Ghana, and P553L in an Angolan isolate. In Tanzania, three (L263E, E431K, S769N) of the four mutations (L263E, E431K, A623E, S769N) in pfatpase6 gene associated with high in vitro IC50 were reported. pfcoronin polymorphisms were reported in Senegal, Gabon, Ghana, Kenya, and Congo, with P76S being the most prevalent mutation.

CONCLUSIONS

This meta-analysis provides an overview of the prevalence and widespread distribution of pfk13, pfcoronin and pfatpase6 mutations in Africa. Understanding the phenotypic consequences of these mutations can provide information on the efficacy status of artemisinin-based treatment of malaria across the continent.

Effects of commonly used food additives on haematological parameters of Wistar rats

This study was done to investigate the effects of common food additives such as sodium benzoate (SB) and ascorbic acid (AA) on haematological parameters of male Wistar rats. Forty-eight (48) male albino rats with an average weight of 105 g were grouped into twelve (n = 4) of Basal Control and other 11 groups orally administered 1 mg of SB, 10 mg of SB, 10 mg of AA, 0.2 mg of AA + 0.5 mg of SB, 0.2 mg of AA + 1 mg of SB, 0.2 mg of AA + 10 mg of SB, 0.2 mg of SB + 0.1 mg of AA, 0.2 mg of SB + 0.5 mg of AA, carbonated soft drinks (CSD)+ 0.1 mg of AA, CSD + 1 mg of AA and CSD + 10 mg of AA, respectively for 21 non-consecutive days. At the end of the experiment, blood samples were collected in EDTA anticoagulant tubes, haematological parameters were evaluated, and data were analyzed. There was a dose-dependent increase (p < 0.05) in White Blood Cell counts of SB treated rats compared with the control group. The lymphocyte exhibited significant reduction (p < 0.05) in the groups treated with 1mg SB and 10mg SB/kg bodyweight of 67 ± 2.96 and 58 ± 4.18%, respectively. The mean corpuscular haemoglobin showed no significant difference at 95% confidence interval. However, mean corpuscular haemoglobin concentration, haematocrit and platelet were affected by an increase in the concentrations of SB. High SB concentrations increased the destruction of erythrocytes, which directly increased the catabolism of haemoglobin. However, AA administration mitigated the adverse effects of SB on the haematological parameters of the animal.

Molecular docking analysis of Plasmodium falciparum dihydroorotate dehydrogenase towards the design of effective inhibitors

Malaria remains a global public health burden with significant mortality and morbidity. Despite the several approved drugs available for its management, the parasite has developed resistance to virtually all known antimalarial drugs. The development of a new drug that can combat resistant to Artemisinin based Combination Therapies (ACTs) for malaria is imperative. Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH), a flavin-dependent mitochondrial enzyme is vital in the parasite's pyrimidine biosynthesis is a well-known drug target. Therefore, it is of interest to document the MOLECULAR DOCKING analysis (using Maestro, Schrodinger) data of DIHYDROOROTATE DEHYDROGENASE PfDHODH from P. falciparum towards the design of effective inhibitors. The molecular docking features of 10 compounds with reference to chloroquine with PfDHODH are documented in this report for further consideration.

Machine Learning-Based Hyperglycemia Prediction: Enhancing Risk Assessment in a Cohort of Undiagnosed Individuals

Background

Noncommunicable diseases continue to pose a substantial health challenge globally, with hyperglycemia serving as a prominent indicator of diabetes.

Objective

This study employed machine learning algorithms to predict hyperglycemia in a cohort of individuals who were asymptomatic and unraveled crucial predictors contributing to early risk identification.

Methods

This dataset included an extensive array of clinical and demographic data obtained from 195 adults who were asymptomatic and residing in a suburban community in Nigeria. The study conducted a thorough comparison of multiple machine learning algorithms to ascertain the most effective model for predicting hyperglycemia. Moreover, we explored feature importance to pinpoint correlates of high blood glucose levels within the cohort.

Results

Elevated blood pressure and prehypertension were recorded in 8 (4.1%) and 18 (9.2%) of the 195 participants, respectively. A total of 41 (21%) participants presented with hypertension, of which 34 (83%) were female. However, sex adjustment showed that 34 of 118 (28.8%) female participants and 7 of 77 (9%) male participants had hypertension. Age-based analysis revealed an inverse relationship between normotension and age (r=-0.88; P=.02). Conversely, hypertension increased with age (r=0.53; P=.27), peaking between 50-59 years. Of the 195 participants, isolated systolic hypertension and isolated diastolic hypertension were recorded in 16 (8.2%) and 15 (7.7%) participants, respectively, with female participants recording a higher prevalence of isolated systolic hypertension (11/16, 69%) and male participants reporting a higher prevalence of isolated diastolic hypertension (11/15, 73%). Following class rebalancing, the random forest classifier gave the best performance (accuracy score 0.89; receiver operating characteristic-area under the curve score 0.89; F1-score 0.89) of the 26 model classifiers. The feature selection model identified uric acid and age as important variables associated with hyperglycemia.

Conclusions

The random forest classifier identified significant clinical correlates associated with hyperglycemia, offering valuable insights for the early detection of diabetes and informing the design and deployment of therapeutic interventions. However, to achieve a more comprehensive understanding of each feature's contribution to blood glucose levels, modeling additional relevant clinical features in larger datasets could be beneficial.

Retraction notice to "Effects of commonly used food additives on haematological parameters of Wistar rats" [Heliyon 6 (2020) e05221]

[This retracts the article DOI: 10.1016/j.heliyon.2020.e05221.].