138 research outputs found
Invivo Antimalarial Activity of Dodonaea Angustifolia Seed Extracts Against Plasmodium Berghei in Mice Model
Dodonaea angustifolia has a wide range of therapeutic applications against various diseases including malaria. This plant is traditionally used for treatment of malaria in different countries including Ethiopia. However, the antimalarial effect and safety of D. angustifolia are not studied. The aim of this study was to evaluate antimalarial activity of Dodonaea angustifolia in Plasmodium berghei infected mice. In the present study, aqueous and hydroalcoholic extracts as well as solvent fractions of the aqueous extract of D. angustifolia seeds were investigated for their antimalarial activity using Peters’ 4-day suppressive test method. Different concentrations of the crude extracts and the fractions of the water extract, most active extract, were orally administered to screen for their antimalarial activities. The extracts significantly inhibited parasitemia and prevented packed cell volume reduction (p <0.05) dose-dependently. Crude extracts and fractions of the aqueous extract of D. angustifolia seeds increased the survival time of infected mice. None of the extracts, however, prevented body weight loss. The aqueous extract of D. angustifolia was found to produce 35.79% parasite suppression. From this extract, three fractions were produced by solvent fractionation technique using butanol, chloroform and water and tested in vivo against P. berghei in mice. The butanol fraction was found to be the most active producing inhibition of 48.6% at 100 mg/kg. The test substance observed to be safe with no toxicity on the mice even at 4500 mg/kg. The results of the present work supported thetraditional use of the plant against malaria and confirmed the antimalarial activity of the plant. Moreover, antimalarial compounds can be isolated from this plant and tested against human malaria parasite in the future.Keywords: Malaria; Dodonaea angustifolia; Extracts; Plasmodium berghe
Arabidopsis RecQl4A suppresses homologous recombination and modulates DNA damage responses
The DNA damage response and DNA recombination are two interrelated mechanisms involved in maintaining the integrity of the genome, but in plants they are poorly understood. RecQ is a family of genes with conserved roles in the regulation of DNA recombination in eukaryotes; there are seven members in Arabidopsis. Here we report on the functional analysis of the Arabidopsis RecQl4A gene. Ectopic expression of Arabidopsis RecQl4A in yeast RecQ-deficient cells suppressed their hypersensitivity to the DNA-damaging drug methyl methanesulfonate (MMS) and enhanced their rate of homologous recombination (HR). Analysis of three recQl4A mutant alleles revealed no obvious developmental defects or telomere deregulation in plants grown under standard growth conditions. Compared with wild-type Arabidopsis, the recQl4A mutant seedlings were found to be hypersensitive to UV light and MMS, and more resistant to mitomycin C. The average frequency of intrachromosomal HR in recQl4A mutant plants was increased 7.5-fold over that observed in wild-type plants. The data reveal roles for Arabidopsis RecQl4A in maintenance of genome stability by modulation of the DNA damage response and suppression of HR.
Smc5/6: a link between DNA repair and unidirectional replication?
Of the three structural maintenance of chromosome (SMC) complexes, two directly regulate chromosome dynamics. The third, Smc5/6, functions mainly in homologous recombination and in completing DNA replication. The literature suggests that Smc5/6 coordinates DNA repair, in part through post-translational modification of uncharacterized target proteins that can dictate their subcellular localization, and that Smc5/6 also functions to establish DNA-damage-dependent cohesion. A nucleolar-specific Smc5/6 function has been proposed because Smc5/6 yeast mutants display penetrant phenotypes of ribosomal DNA (rDNA) instability. rDNA repeats are replicated unidirectionally. Here, we propose that unidirectional replication, combined with global Smc5/6 functions, can explain the apparent rDNA specificity
Selected reactive oxygen species and antioxidant enzymes in common bean after Pseudomonas syringae pv. phaseolicola and Botrytis cinerea infection
Phaseolus vulgaris cv. Korona plants were
inoculated with the bacteria Pseudomonas syringae pv.
phaseolicola (Psp), necrotrophic fungus Botrytis cinerea
(Bc) or with both pathogens sequentially. The aim of the
experiment was to determine how plants cope with multiple
infection with pathogens having different attack strategy.
Possible suppression of the non-specific infection with
the necrotrophic fungus Bc by earlier Psp inoculation was
examined. Concentration of reactive oxygen species
(ROS), such as superoxide anion (O2
-) and H2O2 and
activities of antioxidant enzymes such as superoxide dismutase
(SOD), catalase (CAT) and peroxidase (POD) were
determined 6, 12, 24 and 48 h after inoculation. The
measurements were done for ROS cytosolic fraction and
enzymatic cytosolic or apoplastic fraction. Infection with
Psp caused significant increase in ROS levels since the
beginning of experiment. Activity of the apoplastic
enzymes also increased remarkably at the beginning of
experiment in contrast to the cytosolic ones. Cytosolic
SOD and guaiacol peroxidase (GPOD) activities achieved
the maximum values 48 h after treatment. Additional forms
of the examined enzymes after specific Psp infection were
identified; however, they were not present after single Bc
inoculation. Subsequent Bc infection resulted only in
changes of H2O2 and SOD that occurred to be especially
important during plant–pathogen interaction. Cultivar Korona
of common bean is considered to be resistant to Psp and mobilises its system upon infection with these bacteria.
We put forward a hypothesis that the extent of defence
reaction was so great that subsequent infection did not
trigger significant additional response
Invitro Antibacterial Screening of Extracts from Selected Ethiopian Medicinal Plants
Indigenous knowledge, literature reports and ethnobotanical records suggest that plants are the basis for medicines. They constitute natural source of antimicrobial drugs that will provide novel or lead compounds for the fight against disease. In this study, the antimicrobial activity of three selected Ethiopian medicinal plants was studied with the objective of screening their antibacterial activity. The fruits of Measalanceolata, aerial part of Cissus quadrangularis and leaf of Dodonae angustifolia were collected, air dried under shed, powdered and soaked in 80% methanol and extracted. In vitro antibacterial activity of the extracts was tested at different concentrations by using agar disc diffusion method and measuring the zone of inhibition. The plant extracts showed broad spectrum activity against gram positive (S. aureus) as well as gram negative (E. coli) bacteria, except Cissus quadrangularis which did not show any activity against E. coli. Furthermore, the plant extracts had also concentration dependant zone of inhibition against the tested bacteria. In fact, the highest activity was obtained for Dodonae angustifolia at 1000mg/ml against S. aureus. The activities are attributed to the presence of some secondary metabolites present in the tested plants which have been associated with antibacterial activities. This finding suggests that these medicinal plants can be potential source to isolate antibacterial drugs.Keywords: Antibacterial activity, Disc diffusion, E. coli, Plant extract and S. aureus
Predicting adverse birth outcome among childbearing women in Sub-Saharan Africa: employing innovative machine learning techniques.
BACKGROUND: Adverse birth outcomes, including preterm birth, low birth weight, and stillbirth, remain a major global health challenge, particularly in developing regions. Understanding the possible risk factors is crucial for designing effective interventions for birth outcomes. Accordingly, this study aimed to develop a predictive model for adverse birth outcomes among childbearing women in Sub-Saharan Africa using advanced machine learning techniques. Additionally, this study aimed to employ a novel data science interpretability techniques to identify the key risk factors and quantify the impact of each feature on the model prediction. METHODS: The study population involved women of childbearing age from 26 Sub-Saharan African countries who had given birth within five years before the data collection, totaling 139,659 participants. Our data source was a recent Demographic Health Survey (DHS). We utilized various data balancing techniques. Ten advanced machine learning algorithms were employed, with the dataset split into 80% training and 20% testing sets. Model evaluation was conducted using various performance metrics, along with hyperparameter optimization. Association rule mining and SHAP analysis were employed to enhance model interpretability. RESULTS: Based on our findings, about 28.59% (95% CI: 28.36, 28.83) of childbearing women in Sub-Saharan Africa experienced adverse birth outcomes. After repeated experimentation and evaluation, the random forest model emerged as the top-performing machine learning algorithm, with an AUC of 0.95 and an accuracy of 88.0%. The key risk factors identified were home deliveries, lack of prenatal iron supplementation, fewer than four antenatal care (ANC) visits, short and long delivery intervals, unwanted pregnancy, primiparous mothers, and geographic location in the West African region. CONCLUSION: The region continues to face persistent adverse birth outcomes, emphasizing the urgent need for increased attention and action. Encouragingly, advanced machine learning methods, particularly the random forest algorithm, have uncovered crucial insights that can guide targeted actions. Specifically, the analysis identifies risky groups, including first-time mothers, women with short or long birth intervals, and those with unwanted pregnancies. To address the needs of these high-risk women, the researchers recommend immediately providing iron supplements, scheduling comprehensive prenatal care, and strongly encouraging facility-based deliveries or skilled birth attendance
Brevicoryne brassicae aphids interfere with transcriptome responses of Arabidopsis thaliana to feeding by Plutella xylostella caterpillars in a density‑dependent manner
Plants are commonly attacked by multiple herbivorous species. Yet, little is known about transcriptional patterns underlying plant responses to multiple insect attackers feeding simultaneously. Here, we assessed= transcriptomic responses of Arabidopsis thaliana plants to simultaneous feeding by Plutella xylostella caterpillars and Brevicoryne brassicae aphids in comparison to plants infested by P. xylostella caterpillars alone, using microarray analysis. We particularly investigated how aphid feeding interferes with the transcriptomic response to P. xylostella caterpillars and whether this interference is dependent on aphid density and time since aphid attack. Various JA-responsive genes were up-regulated in response to feeding by P. xylostella caterpillars. The additional presence of aphids, both at low and high densities, clearly affected the transcriptional plant response to caterpillars. Interestingly, some important modulators of plant defense signalling, including WRKY transcription factor genes and ABA-dependent genes, were differentially induced in response to simultaneous aphid feeding at low or high density compared with responses to P. xylostella caterpillars feeding alone. Furthermore, aphids affected the P. xylostella-induced transcriptomic response in a density dependent manner, which caused an acceleration in plant response against dual insect attack at high aphid density compared to dual insect attack at low aphid density. In conclusion, our study provides evidence that aphids influence the caterpillar-induced transcriptional response of A. thaliana in a density-dependent manner. It highlights the importance of addressing insect density to understand how plant responses to single attackers interfere with responses to other attackers and thus underlines the importance of the dynamics of transcriptional plant responses to multiple herbivory
Pathotype determination of sorghum anthracnose (Colletotrichum sublineola) isolates from Ethiopia using sorghum differentials
IntroductionSorghum anthracnose, caused by Colletotrichum sublineola, is the most destructive disease of sorghum, which causes up to 80% grain yield loss in susceptible varieties. The use of resistance varieties is an effective, durable, and eco-friendly strategy for anthracnose control. Knowledge of the phenotypic and genetic variation in C. sublineola is vital for designing appropriate anthracnose management strategies.MethodsThe present study examined the morphology and virulence of 25 C. sublineola isolates recovered from various sorghum-producing regions of Ethiopia against 18 known sorghum anthracnose differentials, 6 Ethiopian sorghum landraces, and a variety of Bonsa.ResultsAnalysis of variance (ANOVA) revealed significant differences among sorghum genotypes, C. sublineola isolates, and their interactions. There was a significant difference between the isolates in virulence, with each isolate exhibiting virulence in 8–72% of the sorghum genotypes tested. Among the 25 tested isolates, the top four most virulent isolates were from Pawe, suggesting that this area is suitable for pathogen diversity studies and host plant resistance screening. The sorghum genotypes IS_18760, Brandes, and Bonsa showed resistance to all tested isolates. Consequently, they may provide potential sources of resistance genes for sorghum breeding programs to develop cultivars resistant to different C. sublineola pathotypes. However, the resistant check SC748-5 was susceptible to isolates NK73_F37, while another resistant check SC112-14 was susceptible to isolates PW123_F47 and PW122_F47. Cluster analysis grouped 22 isolates into seven clusters based on their morphological characters, whereas 24 pathotypes were identified among 25 isolates that were tested on 25 sorghum genotypes.DiscussionHence, this study revealed high variation in C. sublineola in Ethiopia suggesting the need for broad-spectrum resistance to control the disease. Sorghum genotypes resistant to various C. sublineola isolates were identified in this study, which can be used in sorghum breeding programs aiming to develop resistant cultivars to anthracnose. Highly virulent C. sublineola isolates were also identified which could be used in sorghum germplasm resistance screening. The report is the first to show the existence of C. sublineola pathotypes in Ethiopia
Two-Thirds of Smear-Positive Tuberculosis Cases in the Community Were Undiagnosed in Northwest Ethiopia: Population Based Cross-Sectional Study
Background: Tuberculosis (TB) case detection rate remains low in Ethiopia. One of the underlying reasons is the emphasis on passive case finding strategy which may seriously underestimate the burden of the disease. Estimating the prevalence of smear-positive pulmonary TB through active case finding at population level can help assessing the degree to which passive case detection is successful. Methods and findings: This is population based cross-sectional study. The study population was all individuals aged 15 days) and the two sputum (spot and morning) samples were gathered for standard smear microscopy. A total of 23,590 individuals aged 15 days. Of 831 individuals who provided two sputum samples for acid fast bacilli (AFB), 41 had positive smears. A total of 22 smear-positive TB cases detected through passive case finding were on anti-TB treatment. The prevalence of new smear-positive TB was 174 per 100,000 in persons aged 45 years [AOR: 2.26, 95 % CI (1.12–4.59). Conclusions: The study revealed that about two-thirds of patients with active TB remain undiagnosed and thus untreated. This may indicate the need for strengthening case detection at the community level. Furthermore, the high burden of T
EnDPoINT: protocol for an implementation research study to integrate a holistic package of physical health, mental health and psychosocial care for podoconiosis, lymphatic filariasis and leprosy into routine health services in Ethiopia
Introduction Neglected tropical diseases (NTDs) causing lower limb lymphoedema such as podoconiosis, lymphatic filariasis (LF) and leprosy are common in Ethiopia. Routine health services for morbidity management and disability prevention (MMDP) of lymphoedema caused by these conditions are still lacking, even though it imposes a huge burden on affected individuals and their communities in terms of physical and mental health, and psychosocial and economic outcomes. This calls for an integrated, holistic approach to MMDP across these three diseases.
Methods and analysis The ‘Excellence in Disability Prevention Integrated across NTDs’ (EnDPoINT) implementation research study aims to assess the integration and scale-up of a holistic package of care—including physical health, mental health and psychosocial care—into routine health services for people with lymphoedema caused by podoconiosis, LF and leprosy in selected districts in Awi zone in the North–West of Ethiopia. The study is being carried out over three phases using a wide range of mixed methodologies. Phase 1 involves the development of a comprehensive holistic care package and strategies for its integration into the routine health services across the three diseases, and to examine the factors that influence integration and the roles of key health system actors. Phase 2 involves a pilot study conducted in one subdistrict in Awi zone, to establish the care package’s adoption, feasibility, acceptability, fidelity, potential effectiveness, its readiness for scale-up, costs of the interventions and the suitability of the training and training materials. Phase 3 involves scale-up of the care package in three whole districts, as well as its evaluation in regard to coverage, implementation, clinical (physical health, mental health and psychosocial) and economic outcomes.
Ethics and dissemination Ethics approval for the study has been obtained in the UK and Ethiopia. The results will be disseminated through publications in scientific journals, conference presentations, policy briefs and workshops.
https://creativecommons.org/licenses/by/4.0/
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