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Polymorphism of pfmdr1 gene mutation conferring resistance to artemisinin‐based combination therapy in plasmodium falciparum in patients at Gulu regional referral hospital in northern Uganda
(John Wiley & Son, 2026-06-09) Amito, Florence Peace; Angwech, Harriet; Ojok, Lonzy; Wokorach, Godfrey; Ochaya, Stephen; Ogwang, Quinto; Opiro, Robert; Echodu, Richard
Background Malaria is one of the most devastating infectious diseases in humans, and antimalarial drugs have been used to combat it with minimal success. Worldwide, malaria treatment is threatened by the emergence and spread of artemisinin resistance, which is associated with mutations in the PfK13 propeller domain. In Sub-saharan Africa, data relating to the prevalence of Plasmodium falciparum malaria infection in association with the Kelch 13 mutations are mainly from research settings outside disease-endemic areas. This study is aimed at establishing the prevalence of P. falciparum malaria infection in association with Kelch 13 mutations among patients presenting with fever at Gulu Regional Referral Hospital (GRRH) in northern Uganda. Methods This cross-sectional study enrolled all participants presenting with fever at GRRH between April 2022 and January 2024. Data on adults and children aged ≥ 6 months with fever and confirmed diagnosis of malaria using mRDT, microscopy, and PCR were collected. Parasite DNA was extracted using the Chelex method and sequenced for multidrug resistance genes, and Sanger customized CRF forms were used to capture variables on social demographics, clinical presentation, and treatment. Data were analyzed using IBM SPSS Version 25, and the sequenced data were analyzed using molecular evolutionary genetic analysis (MEGA) Version 11.1.10. All sequences from a single population were aligned using the National Center for Biotechnology Information (NCBI) database. Results In total, 353 participants were recruited, and the overall prevalence of P. falciparum malaria was 60.6% (n = 214), with the highest number of cases registered in Gulu City (24.9%). Women were the most affected participants (37.1%). The most common clinical presentations among the participants were fever (91.8%; n = 324), chills (90.7%; n = 320), and headaches (72.0%; n = 254). Genotyping results of the mutant genes showed that of all 214 P. falciparum isolates examined, the pfmdr1 SNP at Codon 1034 1042 (29.6%, n = 94) had the highest prevalence, followed by the pfmdr SNP at Codon 86 184 (28%, n = 89), and the SNP fragment at codon 1246 (25.8%, n = 82) recorded the lowest prevalence. Kelch 13 propeller gene, known to be associated with artemisinin resistance, was also isolated in 16.7% (n = 53) of the samples. There was a 90.1% (n = 318) prevalence of the SNPs 86 184, 1034 1042 of the pfmdr1 gene, and K13 propeller gene, with no significant difference between the sexes (p = 0.756). The SNP at Codon 1246 of pfmdr1 showed a significant difference between the location and mutation (p = 0.017). The median parasite load in patients with mutations in 86 184, 1034 1042, and K13 propeller genes varied significantly among patients who received treatment p ≤ 0.0001, p = 0.0061, and p = 0.012, respectively. Conclusion The presence of pfmdr1 mutant genes suggests resistance of P. falciparum to most antimalarial drugs used in treatment. Therefore, it is important to monitor the prevalence of Kelch 13 mutations and P. falciparum to contribute to global efforts to control and eliminate malaria.
Genomic architecture of fourth-generation cephalosporin-resistant Klebsiella pneumoniae Species Complex (KpSC) from patients and their hospital environment in Uganda
(Springer Nature, 2026-06-01) Byarugaba, Denis K.; Wokorach, Godfrey; Hounmanou, Yaovi M.H.; Wanyana, Agnes; Alafi, Stephen; Wabwire‑Mangen, Fred; Christensen, Henrik; Olsen, John E.
The emergence of fourth-generation cephalosporin-resistant (4GCR) K. pneumoniae species complex (KpSC) is a human health concern due to limited therapeutic options and association of the bacteria with severe morbidity and mortality. This study investigated the genomic characteristics of 4GCR K. pneumoniae species complex strains from patients and their hospital environment in Uganda. Twenty-seven isolates were obtained from two tertiary healthcare hospitals in Uganda. Whole genomic sequence (WGS) analysis revealed dominance of phylogroup Kp1 (70.4%). Isolates were highly diverse genetically, representing 15 clonal groups and 10 different serotypes, with isolates of CG17 (6/27) and serotype O5 (25%) as the most common. Core genome SNP-based phylogenetic comparison placed Ugandan strains together with strains from African lineages; however, with a few strains clustering with global references. Most strains carried multiple resistance genes, particularly CTX-M-15 (24/27) and aminoglycoside-modifying enzymes. A search for virulence factors revealed that most isolates carried few virulence genes, particularly those associated with hypervirulence. A yersiniabactin loci was detected in a subset of Kp1 isolates. Ten plasmid replicons and multiple insertion sequences were detected that may mediate resistance dissemination. These findings provide evidence of 4GCR KpSC in clinical settings and patient environments in Uganda. This underscores the need for ongoing genomic surveillance and antimicrobial stewardship to enable early detection of resistant strains and prevent localized clusters from escalating into widespread outbreaks in hospitals across the country.
Effect of cumulative exposure to media channels for malaria messages on knowledge of malaria prevention among women (15– 49 years) in Uganda
(Springer Nature, 2026-05-05) Natuhamya, Charles; Obiora, Rejoice Uche; Nwankwo, Gideon Ikemdinachi; Agbi, Delight Mawufemor; Isiko, Isaac; Mwebesa, Edson
Introduction Malaria remains a leading global public health concern, disproportionately affecting populations in low-resource settings. Uganda continues to contribute substantially to the global malaria burden, yet exposure to malaria-related health messages remains limited. In recent years, diverse media platforms have been adopted to disseminate prevention messages. This study assessed the influence of cumulative exposure to malaria message media channels on knowledge of malaria prevention and its associated factors among women of reproductive age in Uganda. Methods We conducted a secondary analysis of the 2018–2019 Uganda Malaria Indicator Survey (UMIS), comprising 7124 women aged 15–49 years selected using a two-stage cluster and stratified sampling design. Knowledge of four prevention methods recommended by World Health Organization (WHO), bed nets, insecticide-treated nets (ITNs), preventive medicine, and indoor residual spraying (IRS) was assessed. Associations between cumulative media exposure and malaria knowledge were examined using t-tests, margins analysis, and mixed-effects negative binomial regression models. Results Knowledge of malaria prevention was unevenly distributed: 76.5% of women reported awareness of bed nets, compared with only 9.1% for ITNs, 6.2% for preventive medicine, and 4.3% for IRS. Cumulative exposure to media channels was significantly associated with knowledge of ITNs (p < 0.001), preventive medicine (p = 0.002), and IRS (p < 0.001), but not bed nets. Education, age, wealth, residence, and region were significant determinants of exposure to media channels. Women with secondary or higher education were nearly twice as likely to report exposure to multiple channels compared to uneducated women (Incidence Rate Ratio, IRR = 1.86; 95% Confidence Interval, CI 1.59–2.17). Similarly, women aged ≥ 40 years were 69% more likely (IRR = 1.69; 95% CI 1.35–2.11) to report exposure to multiple channels than those under 20 years. In contrast, rural and refugee women reported significantly lower exposure relative to urban residents (IRR = 0.77 and 0.28, respectively). Conclusions Cumulative multi-channel exposure to malaria prevention messages significantly improves women’s knowledge of ITNs, preventive medicine, and IRS. However, structural inequities in education, wealth, and place of residence limit access to diverse channels. Integrated, context-specific, and equity-focused communication strategies are essential to broaden awareness beyond bed nets and to accelerate progress toward malaria control and elimination in Uganda.
Participants’ experiences of potential adverse effects of an intervention to improve critical thinking about health choices: a qualitative cross-trial process evaluation in Kenya, Rwanda and Uganda
(BMJ Publishing Group, 2025-09-29) Oxman, Matt; Chesire, Faith; Mugisha, Michael; Ssenyonga, Ronald; Nsangi, Allen; Oxman, Andrew D; Fretheim, Atle; Rosenbaum, Sarah; Kaseje, Margaret; Sewankambo, Nelson; Melby-Lervåg, Monica; Lewin, Simon
Objectives: To explore participants’ experiences of potential adverse effects of the Informed Health Choices secondary school intervention across three trial sites and to revise a framework of potential adverse effects of interventions to improve critical thinking about health choices. Design: This was a qualitative study. We extracted and analysed relevant data from separate process evaluations in each country. Data came from surveying teachers, observing lessons and group and individual interviews with students, teachers and other stakeholders. We modified and applied framework analysis, including five stages: (1) development of an initial framework of potential adverse effects, (2) familiarisation with the data, (3) indexing, (4) abstraction and synthesis and (5) revising the framework. We applied reflexive strategies individually and as a team. Setting: Lower secondary school in five randomly sampled subcounties of Kisumu County in Kenya, districts representing all five provinces in Rwanda, and six districts in the central region of Uganda, between 2022 and 2024. Participants: Students and teachers in the intervention arms of the trials, parents of students in the intervention arms and administrators at intervention schools, as well as curriculum developers and policy-makers. Intervention: The intervention involved providing teachers with a 2–3-day training workshop, and digital classroom resources, including lesson plans for 10 lessons to be delivered over the course of one semester. Results: We generated findings about potential increases in adverse misunderstandings, anxiety related to transfer of learning, adversely experienced cognitive dissonance, work or schoolwork-related stress, inequity, conflicts and waste. The revised framework includes the same categories of potential adverse effects as our initial framework: decision-making harms, psychological harms, equity harms, group and social harms, waste and other harms. We revised other elements of the framework, including definitions of the categories and its structure. Conclusions: This study provides insight into the potential adverse effects of interventions to improve critical thinking about health choices. The findings complement those of the trials and country-level process evaluations.
A two-decade review of human exposure to legacy and emerging organic pollutants in Sub-Saharan Africa: Current status, exposure pathways, challenges and recommendations
(Elsevier, 2026-06) Ssebugere, Patrick; Miiro, Ashirafu; Odongo, Silver; Muhwezi, Godfrey; Nabuuma, Josephine; Abayi, Juma John Moses; Matovu, Henry
Rapid urbanization, industrialization, and continued pesticide use have intensified human exposure to persistent organic pollutants (POPs) in Sub-Saharan Africa (SSA). POPs are highly stable, bioaccumulative, and toxic, posing chronic reproductive, endocrine, and developmental risks. This review synthesized studies (2005–2025) that assessed legacy and emerging POPs—including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and per- and polyfluoroalkyl substances (PFAS)—in human fluids and tissues across SSA. Blood and serum (⁓48%) and breast milk (⁓38%) were the most analyzed matrices, followed by urine, placenta, and cord blood (<10%). Total dichlorodiphenyltrichloroethane (∑DDT) in milk samples from South African mothers were in the range of 9500–140,000 ng/g lw—the highest globally—linked to malaria vector control. Mean total PCBs reached 160 ng/g lw in Ghanaian and Nigerian mothers, while ∑PBDEs were up to 786 ng/g lw in exposed Tanzanian populations. Dioxin toxic equivalents in Ghanaian serum (4.2 pg WHO 2005-TEQ/g lw) and South African milk (1.6–9.1 pg TEQ/g lw) were within global mid-range values. PFAS levels in South African and Ethiopian serum (0.6–2.5 ng/mL) confirmed emerging fluorinated exposure. Although health risk assessments were limited, some exceeded FAO/WHO thresholds, suggesting potential endocrine and developmental effects. Median POP levels in SSA populations were lower than the global averages but exhibited localized exceedances. Strengthened biomonitoring, harmonized QA/QC, and inclusion of short-chain PFAS, novel brominated flame retardants (NBFRs), and bisphenol analogues are essential to implement the Stockholm and Basel Conventions.
Comparison of ionospheric irregularities observed by the COSMIC satellites with ground-basedscintillationobservationsoverthelowlatitudeAfricanRegion
(Elsevier, 2026-04-07) Mungufeni, Patrick; Migoya-Orue, Yenca; Aol, ItalySharon; Omondi, George
This study compared the ionospheric irregularities as observed using two different techniques, namely; the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites and the scintillation intensity index(S4) data measured by the Scintillation Network and Decision Aid (SCINDA) receiver which operated at Nairobi University (geog lon 36.8 E, geog lat 1.3 S, dip lat−24.1, Kenya. The data compared were those of the years 2009 (low solar activity) and2011(ascending phase of solar cycle24), for both quiet (Kp3) and disturbed(Kp5) geomagnetic conditions. For the cases of Global Positioning System (GPS)satelliteswithelevationangle0as observed by the COSMIC satellites, a geo-location of the COSMIC S4 data associated with the link between GPS and COSMIC satellites was proposed at the tangent point. The COSMIC S4 data whose geo-locations fall in the vicinity of Nairobi were compared with the S4 data measured by the SCINDA receiver. The coefficient of determination which represents the percentage of the variation in COSMIC S4 data associated with the variation in SCINDA S4 was 50 %. The two data sets depict that scintillation occurs mostly in the seasons of March and September equinoxes of high solar activity conditions. However, there was a moderate positive correlation (Pearson correlation coefficient, r=0.52 on quiet days) between COSMIC and SCINDA S4 data. The results presented signify that the COSMIC S4 could be analyzed to study ionospheric irregularities (which cause scintillations) over locations such as deserts and oceans where it is usually difficult to deploy equipment.
Women’s decision-making autonomy and early antenatal care initiation in Ghana: a propensity score-matched analysis
(Springer Nature, 2026-03-03) Agbi, Delight Mawufemor; Nwankwo, Gideon Ikemdinachi; Mawuko, Courage Venunye; Iha, Daniel Thoya; Djossou, Josias Ounsinli; Mwebesa, Edson
Introduction Women’s decision-making autonomy is widely recognized as an important determinant of maternal health behaviors such as the timing of antenatal care (ANC) initiation in low- and middle-income countries. However, empirical evidence from Ghana on this relationship, particularly using causal inference approaches, remains limited. This study investigates the effect of women’s decision-making autonomy on the early initiation of ANC visits in Ghana. Methods Data were sourced from the 2022 Ghana Demographic and Health Survey (GDHS), including 4,314 women aged 15–49 years with a birth in the preceding three years before the survey. Autonomy was measured as a composite index from household decision-making participation. Propensity Score Matching (PSM) was used to match women with High and None/Low autonomy, based on covariates like age, education, wealth, and residence. The average treatment effect on the treated (ATT) was estimated to assess the impact of high autonomy on early ANC initiation (within the first trimester), compared to the counterfactual scenario in which the same women lacked such autonomy. Results Among the women included in the study, 25.3% reported high decision-making autonomy, and 66.4% initiated ANC early. Women with high autonomy were more likely to be older (30–49 years), educated (secondary or higher), married, employed, Christian, insured, urban residents, and from wealthier households. After matching on socio-demographic covariates, no statistically significant effect of high autonomy on early ANC initiation was observed [-0.029; 95% CI: -0.081 to 0.022]. Conclusion Women’s decision-making autonomy, when measured through household decision-making participation and within the Ghanaian context, does not independently drive early ANC initiation, suggesting that broader structural and contextual barriers may constrain the translation of autonomy into early care-seeking.
Unlocking Ugandan pumpkin landrace diversity: integrated morphological and nutritional profiling for food security and breeding innovation
(Taylor & Francis, 2026-04-13) Masika, Fred Bwayo; Anywar, Godwin; Kesawate, Mahipal Singh; Ddamulira, Gabriel; Kawuma, Caro; Andama, Morgan; Ajoma, Charity; Ramathan, Iddi; Amugoli, Otuba Moses; Caku, Jimmy; Alicai, Titus; Nuwamanya, Ephraim; Tugume, Arthur K.
Pumpkins (Cucurbita spp.) are vital for food and nutritional security in Uganda, yet their full potential remains underexploited due to the limited characterization of traits. To address this, 91 landraces, 21 Cucurbita pepo and 70 Cucurbita moschata were collected from 19 districts across major agroecological zones, evaluated for morpholological and nutritional diversity. Results revealed wide phenotypic variation with fruit weights ranging from 0.5 to 10.0 kg and shapes varying from discoid (L/D 0.44) to highly elongated (L/D 4.00). Fruit size and shape were independent axes of variation. Regionally, Buganda and Bunyoro landraces produced larger fruits, averaging 3.84 kg and 4.07 kg, while West Nile landraces formed a distinct nutrient-rich cluster, with high dry matter (22.8%), lipids (3.75% fresh weight (FW), fiber (3.34% FW), and carbohydrates (4.07% FW). District-specific differences were also observed, with Mpigi landraces rich in phenolics content (0.062 ± 0.0023 g GAE/100 g), and Mukono landraces rich in proteins (0.000887 g/100 g). Importantly, external morphology poorly predicted internal nutritional quality, highlighting the need for direct biochemical profiling in breeding programs. This study provides Uganda’s first nationally structured dataset on pumpkin diversity, offering a scientific foundation for targeted germplasm conservation, nutrient-enriched cultivar development and policy interventions to strengthen food systems across diverse agroecological zones in Uganda.
An improved Agrobacterium-mediated transformation method for genome editing using CRISPR/Cas9 in elite indica rice (Oryza sativa L.)
(Springer Nature, 2026-04-07) Behera, Laxmipreeya; Samal, Kailash Ch.; Parameswaran C,; Agrawal, Pawan Kumar; Achary, V. Mohan Murali; Dash, Manasi; Mishra, Ashok; Rani, Manjusha; Masika, Fred Bwayo; Goud, Gurunatham Sai Deekshith; Kesawat, Mahipal Singh; Samantaray, Sanghamitra
Rice feeds nearly half of the world’s population and underpins global food security. Climate change now poses a major threat to rice productivity worldwide. Genome editing has reshaped crop improvement strategies. Among these tools, the Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein (CRISPR/Cas) system stands out for its precision, efficiency, and scalability. However, Agrobacterium-mediated transformation efficiency is often low, particularly in indica rice varieties. Here, we optimized an Agrobacterium-mediated transformation protocol for indica rice cultivars. The method was established in Lalat and MTU-1010. Seed-derived embryogenic calli were used to introduce the thermosensitive genic male sterile (OsTMS5) gene. A CRISPR/Cas9 vector carrying a gRNA and the selectable marker hptII was used for transformation. Callus induction reached 96.87% in MTU-1010 and 93.30% in Lalat MS medium supplemented with 3 mg/L 2,4-D and 0.5 mg/L BAP. In contrast, regeneration efficiency was higher in Lalat (90.28%) than in MTU-1010 (87.51%) on MS medium supplemented with 0.25 mg/L NAA, 0.5 mg/L kinetin, and 2 mg/L BAP. In addition, PCR analysis further verifies the integration of the transgene. Subsequently, the transformation efficiency was 37.20% in Lalat and 29.62% in MTU-1010. Therefore, this protocol provides a robust platform for gene function analysis and trait editing in rice. Its application may accelerate yield improvement and enhance stress tolerance under changing climatic conditions.
Comparative analysis of oil palm extraction rates and nutritional profiles of indigenous and introduced hybrid genotypes cultivated in selected districts of Uganda
(Taylor & Francis, 2026-04-04) Caku, Jimmy; Ddamulira, Gabriel; Nuwamanya, Ephraim; Ddumba, Gerald; Mahipal, Kesawat Singh; Asiimwe, Alex; Amugoli, Otuba Moses; Alicai, Titus; Masika, Fred Bwayo
Oil palm (Elaeis guineensis Jacq. L.) is the leading global source of plant-based oil. However, Uganda relies on imported hybrid varieties because it lacks a domestic breeding program. To inform potential breeding efforts, this study evaluated oil extraction rates and nutritional profiles of indigenous and introduced hybrid oil palm genotypes cultivated in Bundibugyo, Kanungu, and Kalangala districts. Seventy-five ripe fruit bunches were collected, and palm oil was extracted using a screw press. Measurements of oil extraction rate and stearin mass recovery were performed. Nutritional analysis of olein samples included carbohydrate quantification via the Anthrone method; fatty acid quantification (linolenic, linoleic, oleic, palmitic, and stearic acids) using High-Performance Liquid Chromatography (HPLC) with UV detection; and beta-carotene concentration determined using spectrophotometry. Statistical differences between groups were assessed using the non-parametric Kruskal-Wallis H test, as data for most variables did not meet the assumptions for parametric tests. Indigenous genotypes showed slightly higher mean oil extraction rates (23.3%) and stearin recovery (22.6%) than hybrids (22.8 and 17.9%, respectively). These results highlight the potential of indigenous genotypes as promising candidates for breeding programs aimed at enhancing oil yield and nutritional quality under Uganda’s agro-ecological conditions. The study provides foundational data to support the development of a sustainable, locally adapted oil palm breeding initiative.
Utilization of malaria control interventions and associated factors among women of reproductive age in Lira City, Northern Uganda
(Springer Nature, 2026-03-09) Apio, Everline; Angwech, Harriet; Opio, Bosco; Okwir, Gustavio; Opoke, Robert; Malinga, Geoffrey Maxwell; Opiro, Robert
Malaria remains a major public health concern in Uganda, with prevalence in Lira City rising sharply in recent years despite ongoing interventions. Women of reproductive age are particularly vulnerable, yet little is known about their use of available preventive measures. This study assessed knowledge, attitudes, perceptions, and utilization of malaria control interventions, and examined factors influencing their uptake. A cross-sectional study was conducted with 629 randomly selected women of reproductive age in Lira City. Quantitative data were collected using semi structured questionnaires, while qualitative insights were obtained through focus group discussions. Descriptive statistics were used to summarize knowledge, attitudes, perceptions, and use of insecticide-treated nets (ITNs), intermittent preventive treatment (IPT), and indoor residual spraying (IRS). Chi-square tests were used to examine associations, and multivariate logistic regression was applied to identify predictors of utilization. Qualitative data were analyzed thematically to explore barriers to uptake, and findings were triangulated with quantitative results for validation and deeper interpretation. ITN utilization was high (84.1%), IPT uptake moderate (68%), and IRS coverage low (32.8%). Almost all participants (96.8%) were knowledgeable about ITNs, mainly gained through health workers, and expressed positive attitudes toward malaria prevention (mean score: 4.34, SD = 0.67). While most (91.9%) perceived IRS as effective, concerns included bad odor and discomfort (51.7%), doubt about safety (21.9%), and effectiveness (17.3%). Age, type of house, challenges faced with nets, marital status, and exposure to health education were significant predictors of utilization. Despite widespread ITN use, IRS uptake remains limited due to persistent concerns and misconceptions. Strengthening targeted health education, addressing community fears, and improving access to interventions are critical for enhancing malaria control in high-transmission settings like Lira City.
Impact of eight or more antenatal care visits on intermittent preventive treatment of malaria uptake during pregnancy and facility-based delivery in Ghana: a propensity score matched analysis
(Springer Nature, 2026-02-24) Agbi, Delight Mawufemor; Mwebesa, Edson; Jimmy, Abraham Isiaka; Valère, Salako Kolawolé; Kerich, Gregory Kibet
Introduction Maternal and malaria-related morbidity remain major public health challenges in sub-Saharan Africa, particularly in Ghana. The World Health Organization (WHO) recommends eight or more antenatal care (ANC8+) contacts to enhance maternal and child health, but its effect on malaria prevention and delivery outcomes is not well established. This study examined the impact of ANC8 + visits on facility-based delivery and optimal uptake of intermittent preventive treatment for malaria during pregnancy (IPTp-SP). Methods Data were drawn from the 2022 Ghana Demographic and Health Survey, including women aged 15–49 years who had given birth within the three years preceding the survey. Propensity score matching was applied to estimate the effect of ANC8 + visits on facility-based delivery and uptake of at least three IPTp-SP doses. Results Only 38.7% of women met the ANC8 + threshold. Among all respondents, 85.4% delivered in a health facility, and 66.5% received three or more IPTp-SP doses. After matching, ANC8 + attendance increased the likelihood of facility delivery by 8.2% points (ATT = 8.2, 95% CI: 4.6–11.9) and optimal IPTp-SP uptake by 11.1% points (ATT = 11.1, 95% CI: 6.8–15.4). Conclusion Adherence to WHO’s ANC8 + recommendation significantly improves facility-based delivery and malaria prevention during pregnancy. Strengthening policies that enhance ANC attendance, particularly among socioeconomically and geographically disadvantaged groups, is essential for advancing maternal and child health in Ghana.
Profile distribution and health risk assessment of per- and polyfluoroalkyl substances in indoor dust from urban households in Uganda, East Africa
(Elsevier, 2026-02-03)
Per- and polyfluoroalkyl substances (PFAS) contamination of various environmental compartments continues to attract scrutiny due to their persistence, bioaccumulation and toxicity, following their widespread application over the years as surfactants and stain repellents. Studies have indicated that environments, including dust, may serve as sources of human exposure. However, little is known about the prevalence of PFAS and their associated health risks in indoor environments from the sub-Saharan African countries, including Uganda. Herein, we collected samples of indoor household dust from the floors of residential houses (n = 43) in Kampala, Uganda, to assess the levels and associated health risks of PFAS to the exposed humans. Of the 11 targeted PFAS, only 8 were detected in the collected samples. The mean level of ∑8PFAS in household dust was 427 ng/g, with a maximum concentration of 2850 ng/g. 10:2 fluorotelomer alcohol (10:2 FTOH), and perfluorobutanoic acid (PFBA) predominated among the neutral and ionic PFAS, respectively. Source apportionment revealed food packaging, semiconductor materials and textiles as the major sources. The calculated hazard quotients (HQs) due to exposure to PFAS, and their sums (∑HQs) in our study for both adults and toddlers, were all less than 1, suggesting negligible non-carcinogenic risk. Despite the low estimated exposure via dust ingestion and dermal contact, compound-specific toxicological profiles of PFAS, their potential for interactive effects, and the presence of additional exposure routes underscore the urgency of regularly investigating indoor PFAS-related health risks.
Exposure of urban population to organophosphate esters and novel brominated flame retardants via indoor dust: Occurrence, sources and health risks in Uganda, East Africa
(Elsevier, 2026-01-29)
Indoor environments are critical exposure pathways to flame retardants, yet data from Africa remain scarce. This study provides the first quantitative assessment of organophosphate esters (OPEs) and novel brominated flame retardants (NBFRs) in indoor dust from Ugandan households, establishing baseline data for East Africa. Dust samples collected from homes in Kampala were analyzed using gas chromatography–mass spectrometry (GC–MS). Concentrations of total OPEs (Σ5OPEs) and total NBFRs (Σ4NBFRs) ranged from 1520 to 102,000 ng g−1 and 214 to 6600 ng g−1, respectively. Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and 2,4,6-tribromophenyl allyl ether (TBP-AE) dominated OPE and NBFR profiles, respectively. Chlorinated OPEs contributed most to ΣOPEs, reflecting emissions from building materials and consumer products. Principal component analysis indicated household items, electrical equipment, and floor finishes as the major emission sources. Estimated human exposure doses showed that ingestion was the dominant route, with children more exposed than adults. Hazard index (HI) values were below 1 for all compounds, indicating negligible non-carcinogenic risk. Carcinogenic risk (CR) values ranged from 10−6 to 10−12, suggesting minimal lifetime cancer risks, though children exhibited relatively higher vulnerability. Compared with global datasets, OPE and NBFR levels in Kampala were within lower-to-median range but represent the inaugural dataset for sub-Saharan Africa. These findings provide a crucial regional reference for indoor flame-retardant exposure and highlight the need for extended studies across multiple indoor microenvironments to evaluate the long-term exposure pathways and inform safer chemical management.
Evaluation of cosmic-ray damage and doses on hybrid and inorganic halide lead perovskites in space environment
(Elsevier, 2026-02-20) Omojola, Joseph; Engelbrecht, N.E.; Oryema, Bosco; Strauss, R.D.
This study evaluates the radiation damage and doses of hybrid (CH3NH3PbI3) and inorganic (CsPbI3) halide lead perovskites (HLPs) in a simulated space environment utilising the Particle and Heavy Ion Transport code System (PHITS) in its cosmic-ray source mode. Contributions from galactic cosmic rays (GCRs), solar energetic particles (SEPs), and radiation within Low Earth Orbit (LEO) were considered. A crucial comparative simulation with pure Silicon (Si) under identical conditions revealed Si’s superior resistance to radiation damage, while both HLPs exhibited reduced displacement per atom (DPA) at thicknesses 500 nm. The inorganic perovskite, CsPbI3, demonstrated a higher DPA and lower absorbed dose compared to CH3NH3PbI3, attributed to its greater mass density, greater energy per unit volume and higher linear energy transfer (LET). SEPs were identified as the primary cause of material damage due to their higher LET. While the higher mass density of CsPbI3 may lead to greater structural degradation over long-term energy applications, its high energy absorption per unit volume and lower ionisation energy suggest its suitability as a short-term space radiation sensor. Conversely, CH3NH3PbI3, when manufactured with a thickness 500 nm and properly encapsulated, may offer enhanced durability comparable to silicon-based solar cells for a cost-effective and dependable energy source for energy production in space.
Genome-wide survey and expression analysis of peptides containing tyrosine sulfation (PSY) gene family in Cicer arietinum L.
(Springer Nature, 2026-02-21) Kesawat, Mahipal Singh; Kumar, Vinay; Manohar, Swati; Sohail, Aqib; Rani, Manjusha; Chung, Sang-Min; Kumar, Deepak; Lenka, Sangram K.; Masika, Fred Bwayo
Background Plant growth and developmental processes are tightly regulated by small secreted peptides, however, the functions and mechanisms of Tyrosine Sulfation-containing Peptides (PSY) remain unclear. In chickpea, knowledge of PSY genes family is limited. Results This study employed comprehensive bioinformatics approaches to identify and characterize seven CaPSY genes in the chickpea genome. The analyses encompass chromosomal localization, evolutionary relationships, gene structure, conserved motif identification, promoter architecture, prediction of PSY-targeting miRNAs, and expression profiling. Chromosomal mapping revealed that CaPSY genes are confined to four specific chromosomes rather than being evenly distributed across the genome. Phylogenetic analysis resolved nine distinct groups, each further subdivided into subgroups. Additionally, CaPSY genes were found to contain one to two introns. Amino acid sequence comparisons demonstrated that each CaPSY gene consistently harbors a PSY domain in its C-terminal end. Promoter analysis of CaPSY genes revealed the presence of multiple hormone-responsive elements, including ABRE, SARE, AuxRE, and MeJARE, as well as stress-related elements such as the drought-responsive MBS, suggesting potential regulatory roles in development and stress adaptation. Further, the expression patterns of CaPSY were evaluated in multiple tissues as well as in response to abiotic stresses. The results indicated differential expression of CaPSY genes among tissues and under multiple abiotic stress conditions. We further detected several miRNAs likely to target CaPSY genes and assessed how they are expressed in different tissues. Conclusion Thus, these findings serve as a crucial resource for basic and applied research, enabling advancements in chickpea productivity and stress tolerance via precise genome editing and innovative breeding methods.
Seasonal dynamics of Elaeidobius Kamerunicus in allopatric populations: comparative analysis from indigenous mainland and introduced oil palm ecosystems in Uganda’s lake Victoria islands
(Taylor & Francis, 2026-02-04) Masika, Fred Bwayo; Otuba, Amugoli Moses; Kesawat, Mahipal Singh; Asiimwe, Alex; Baguma, Bidget; Alicai, Titus; Manohar, Swati; Ddamulira, Gabriel
Oil palm (Elaeis guineensis L.), native to Africa but widely cultivated in Southeast Asia, is increasingly grown in Uganda, and pollination efficiency is critical for fruit set and oil yield. The study assessed the population and sexual diversity of the primary pollinator, Elaeidobius kamerunicus FAUST, in introduced hybrid plantations in Kalangala and natural stands in Bundibugyo. Pollinator weevils were sampled across both wet and dry seasons in 2022 and 2023, and data were analyzed using ANOVA and correlation tests in Minitab 17. Results revealed significant variation between sites, with higher populations in Kalangala (7,503 ± 8.682) compared to Bundibugyo (5,164 ± 5.829). Furthermore, females (6,636 ± 4.646) outnumbered males (6,032 ± 5.028), with a slightly higher concentration of females in the middle section of male inflorescences. Seasonal differences were evident, as the wet season supported slightly higher weevil populations relative to the dry season. Correlation analysis indicated a weak negative relationship between weevil abundance and weather variables, suggesting that cooler conditions suppress population growth. Overall, Uganda provides favorable conditions for pollinator weevil multiplication, particularly under moist climatic regimes, while extensive cold conditions limit population expansion. These findings highlight the importance of pollinator dynamics in sustaining oil palm productivity in diverse agroecological regions.
Unexplored potential of carrot (Daucus carota L.) bioactive in combating cancer: an insight into intricate mechanisms
(Taylor & Francis, 2026-01-27) Kumar, Santosh; Kesawat, Mahipal Singh; Kherawat, Bhagwat Singh; Singh, Archana; Kumar, Anmol; Kumari, Sweta; Alamery, Salman Freeh; Singh, Pratibha; Masika, Fred Bwayo; Manohar, Swati
The rising incidence of cancer, combined with costs, toxicity, and side effects of conventional treatments such as immunotherapy, chemotherapy, radiotherapy, and surgery, underscores the need for preventive strategies. Natural phyto-bioactives, have attracted increasing scientific interest due to their diverse biological activities. These phytochemicals in carrots have been studied for their roles in modulating intracellular signalling pathways in vitro and preclinical studies. Carrots contain an abundant spectrum of bioactive compounds, including phenolics, carotenoids, polyacetylenes, ascorbic acid, and dietary fiber. These constituents have been reported to modulate processes such as apoptosis, oxidative stress, inflammation, angiogenesis, and pathways involved in cell proliferation in experimental systems. This comprehensive review studies findings from preclinical studies, epidemiological research, and meta-analyses to evaluate the biological activities of carrot bioactives in cancer-relevant biological mechanisms. By examining their ability to modulate molecular pathways involved in tumour invasion and metastasis, this review highlights the potential mechanistic relevance of carrot-derived phytoactive compounds against metastatic cells. Although preclinical studies suggest that these bioactives may influence processes associated with tumour progression, the available evidence is largely derived from in vitro and animal models, and therefore requires validation through translational research and well-designed, large-scale clinical trials. Rather than establishing definitive cancer-preventive or therapeutic effects, current scientific findings support the role of carrot-derived bioactives as promising candidates for further investigation. Advancing research into the underlying molecular mechanisms of carrots may help identify specific phytochemicals that modulate pathways related to tumour invasion and metastasis, therby enabling the development of future cancer prevention strategies.
Trading tomatoes and onions in Uganda’s watersheds: actors, dynamics, and opportunities
(Canadian Center of Science and Education, 2026-01-15) Masika, Fred Bwayo; Ddamulira, Gabriel; Obongo, Isaac; Aropet, Stella Adumo; Asiimwe, Alex; Kiryowa, Moses; Logose, Maureen; Amugoli, Otuba Moses; Naluyimba, Rehema; Ramathan, Idd
Horticulture accounts for more than half of Uganda’s agricultural output, yet crops such as tomatoes and onions remain only marginally profitable despite the country’s favorable climate. To assess the state of their marketing, a study was conducted across five watershed irrigation schemes of Ngenge, Tochi, Wadelai, Mubuku II, and Doho. Researchers interviewed 56 key informants and 174 market vendors using questionnaires that explored market actors, their roles and interconnections, seasonal trade dynamics, pricing, supply and demand, gross margins, and both opportunities and constraints. Data were analyzed using Microsoft Excel and SPSS. The findings showed that nearly half of the markets (46%) were underdeveloped, with women and youth making up the majority of vendors (78%). Farmers were the main suppliers, but often overlapped with other market roles. Seasonal fluctuations affected tomato and onion availability, with oblong tomato varieties being most popular. Key challenges included poor storage facilities, high market fees, and price volatility. However, strong local demand, access to export channels, and opportunities for off-season production highlight promising avenues for improving the profitability and sustainability of tomato and onion marketing in Uganda.
Genome-wide analysis of the pleiotropic drug resistance (PDR) gene family and putative PDR specific miRNAs: deciphering their functions in development processes and varied stresses in Triticum aestivum L.
(Springer Nature, 2026-01-13) Kesawat, Mahipal Singh; Kherawat, Bhagwat Singh; Reager, Madan Lal; Lenka, Sangram K.; Chung, Sang-Min; Masika, Fred Bwayo
Background The pleiotropic drug resistance (PDR) transporter stands out as one of the largest subfamilies within ABC transporters. These transporters play crucial roles in a multitude of biological processes, including detoxification, phytohormone transportation, stomatal movement, the translocation of various secondary metabolites, tolerance to heavy metal and adaptation to the diverse stress conditions. However, the structural and functional characterization of PDR gene family members in wheat has yet to be fully elucidated. Results In this investigation, we identified 66 TaPDR genes in the genome of wheat. The subsequent phylogenetic tree revealed that the genes clustered into four subfamilies. Chromosomal mapping unveiled the dispersal of 66 TaPDR genes across 17 wheat chromosomes. The twenty-two pairs of duplicated gene were identified in the PDR family. Ka/Ks ratio revealed that 22 duplicated TaPDR genes went through purifying selection. It was noted that the TaPDR genes displayed significant diversity in their gene structures. In addition, the presence of numerous cis-regulatory elements in the promoter regions of the TaPDR genes were identified. Differential expression patterns were observed among TaPDR family members across various tissues and in response to multiple stress conditions. Moreover, this investigation explored the miRNAs targeting TaPDR genes and their expression profiles in various tissues. Conclusion Thus, the results of this study establish a strong basis for further investigation of the functions of TaPDR genes across different tissues, developmental stages, phytohormone responses, and diverse stress in wheat.

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