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Antibiotic resistance and virulence profiles of Proteus mirabilis isolated from broiler chickens at abattoir in South Africa
Get PDFArticle, Faculty of Natural and Agricultural Science (Centre for Animal Health Studies)--Northwest University, Mahikeng CampusBackground: Proteus mirabilis has been identified as an important zoonotic pathogen, causing several illnesses such as diarrhoea, keratitis and urinary tract infections.
Objective: This study assessed the prevalence of P. mirabilis in broiler chickens, its antibiotic resistance (AR) patterns, ESBL-producing P. mirabilis and the presence of virulence genes.
Methods: A total of 26 isolates were confirmed as P. mirabilis from 480 pooled broiler chicken faecal samples by polymerase chain reaction (PCR). The disk diffusion method was used to evaluate the antibacterial susceptibility test, while nine virulence genes and 26 AR genes were also screened by PCR.
Results: All 26 P. mirabilis isolates harboured the ireA (siderophore receptors), ptA, and zapA (proteases), ucaA, pmfA, atfA, and mrpA (fimbriae), hlyA and hpmA (haemolysins) virulence genes. The P. mirabilis isolates were resistant to ciprofloxacin (62%) and levofloxacin (54%), while 8 (30.7%) of the isolates were classified as multidrug resistant (MDR). PCR analysis identified the blaCTX-M gene (62%), blaTEM (58%) and blaCTX-M-2 (38%). Further screening for AMR genes identified mcr-1, cat1, cat2, qnrA, qnrD and mecA, 12%, 19%, 12%, 54%, 27% and 8%, respectively for P. mirabilis isolates. The prevalence of the integron integrase intI1 and intI2 genes was 43% and 4%, respectively.
Conclusions: The rise of ciprofloxacin and levofloxacin resistance, as well as MDR strains, is a public health threat that points to a challenge in the treatment of infections ncaused by these zoonotic bacteria. Furthermore, because ESBL producing P. mirabilis has the potential to spread to humans, the presence of blaCTX-M -producing P. mirabilis in broilers should be kept under control. This is the first study undertaken to isolate P. mirabilis from chicken faecal samples and investigate its antibiotic resistance status as well as virulence profiles in South Africa
Interrogating How Differential Motivation in PublicHealthcare Institutions is Undermining Nigeria’s Questfor the Achievement of Sustainable Development Goal(SDG) 3
Get PDFJournal Article, Faculty of Humanities, North--West UniversityWith Sustainable Development Goal (SDG) 3, it is expected that all at all ageswould have healthy lives and well-being by 2030. To achieve this feat, countries,including Nigeria, set up workable mechanisms for its attainment. However, thereality in Nigeria shows that public healthcare institutions suffer fromlimitations that undermine the attainment of SDG 3 (healthy lives andimproved well-being for all). One of such limiting factors is differentialmotivation, which seems to motivate clinicians well above non-clinicians. Whileits use is partly hinged on the fact that clinicians spend more years in trainingAfrican Journal of Development Studies (AJDS)Published consistently since 2012ISSN 2634-3630 E-ISSN 2634-3649Indexed by IBSS, EBSCO, ERIH PLUS, COPERNICUS, ProQuest,SABINET and J-Gate.Special Issue, October 2024pp 97-119Interrogating How Differential Motivation in …98and the tasking nature of their work, it has caused more ravaging disputes that,in turn, have threatened the healthy lives and well-being of Nigerians. It alsothreatens Nigeria’s ability to attain the SDG 3 by 2030, as healthcare workerswho are supposed to render effective coordinated healthcare delivery to thepublic are at war. Drawing on the secondary method sourced through desktopreviews and structural-functionalism, this article examined how the adoption ofdifferential motivation is limiting Nigeria’s capacity to attain SDG 3. Thefindings expanded the discussion on undercurrents of differential motivation inpublic healthcare institutions in Nigeria. The study also suggested meansthrough which the Nigerian government and actors in public healthcareinstitutions can utilise differential motivation in ways that aid Nigeria’sattainment of SDG 3 and health for al
Low circulating levels of neuregulin 4 as a potential biomarker associated with the severity and prognosis of obesity-related metabolic diseases: a systematic review
Get PDFJournal Article. Department of Biochemistry, North-West University, MafikengBackground
Neuregulin 4 (Nrg4) is a brown adipose tissue-derived adipokine that greatly affects systemic metabolism and improves metabolic derangements. Although abnormal circulating levels of Nrg4 are common in obesity, it remains elusive whether low or elevated levels of this batokine are associated with the onset of metabolic diseases.
Aim
To assess Nrg4 levels and its role as a feasible biomarker to predict the severity of obesity, gestational diabetes mellitus (GDM), type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), and cardiovascular diseases (CVD).
Methods
A search for relevant studies was performed systematically using prominent search engines, including PubMed, Google Scholar, and Embase, by following PRISMA guidelines.
Results
Ample clinical evidence reported low serum/plasma levels of Nrg4 in obesity and these were inversely proportional to the indices of metabolic syndrome, including body mass index, waist circumference, triglycerides, fasting plasma glucose, and homoeostatic model assessment for insulin resistance as well as high-sensitivity C-reactive protein. Low circulating Nrg4 levels may aid in the prediction of morbid obesity, and subsequent GDM, T2DM, NAFLD, and CVD.
Conclusion
Current clinical evidence emphasizes that the circulating levels of Nrg4 are decreased in morbid obesity, and it also highlights that Nrg4 May serve as a potential prognostic biomarker for obesity-related metabolic diseases.This work was funded by the National Research Foundation (NRF) Support for NRF-rated scientist 113674 to SE Mazibuko-Mbeje. Research of Capacity Development under the Early Investigators Programme from the South African National Treasury [funding number: HDID8682/MB2022/ EIP052] of the South African Medical Research Council (SAMRC) as well as Northwest University are acknowledged. The content hereof is the sole responsibility of the authors and do not necessarily represent the official views of the SAMRC or the funder
Neutrino Detection Rates from Lepto-hadronic Model Simulations of Bright Blazar Flares
Get PDFJournal Article, Faculty of Natural and Agricultural Sciences, Centre for Space Research (CSR)-- Potchefstroom CampusThere is mounting evidence that blazars are the sources of part of the very-high-energy astrophysical neutrino flux detected by IceCube. In particular, there have been several spatial and temporal coincidences of individual IceCube neutrino events with flaring blazars, the most prominent of them being IceCube-170922A, coincident with a multiwavelength flare of TXS 0506+056. Motivated by this, we used the time-dependent lepto-hadronic code OneHaLe to model the spectral energy distributions and light curves of a sample of bright γ-ray flares of blazars detected by Fermi-Large Area Telescope, for which Kreter et al. provided calorimetric estimates of the expected neutrino detection rates. Flares were modeled with temporal changes of the proton injection spectra. Our analysis shows that the calorimetric approach overestimates the increase in neutrino production by a factor of typically ∼10 if the γ-ray emission is dominated by proton-synchrotron radiation.Acknowledgments
This work was supported by the Department of Science and Innovation and the National Research Foundation of South Africa through the South African Gamma-Ray Astronomy Programme (SA-GAMMA). J.B. is supported by the National
Astrophysics and Space Science Programme (NASSP)
Input margins can predict generalization too
Get PDFConference Contribution, Faculty of Engineering, Multilingual Speech Technologies (MUST)-- Potchefstroom CampusUnderstanding generalization in deep neural networks is an active area of research. A promising avenue of exploration has been that of margin measurements: the shortest distance to the decision boundary for a given sample or its representation internal to the network. While margins have been shown to be correlated with the generalization ability of a model when measured at its hidden representations (hidden margins), no such link between large margins and generalization has been established for input margins. We show that while input margins are not generally predictive of generalization, they can be if the search space is appropriately constrained. We develop such a measure based on input margins, which we refer to as ‘constrained margins’. The predictive power of this new measure is demonstrated on the ‘Predicting Generalization in Deep Learning’ (PGDL) dataset and contrasted with hidden representation margins. We find that constrained margins achieve highly competitive scores and outperform other margin measurements in general. This provides a novel insight on the relationship between generalization and classification margins, and highlights the importance of considering the data manifold for investigations of generalization in DNNs
Acceleration and transport of relativistic electrons in the jets of the microquasar SS 433
No full textJournal Article, Faculty of Natural and Agricultural Sciences, Centre for Space Research (CSR)-- Potchefstroom CampusSS 433 is a microquasar, a stellar binary system with collimated relativistic jets. We observed SS 433 in gamma rays using the High Energy Stereoscopic System (H.E.S.S.), finding an energy-dependent shift in the apparent position of the gamma-ray emission of the parsec-scale jets. These observations trace the energetic electron population and indicate the gamma rays are produced by inverse-Compton scattering. Modelling of the energy-dependent gammaray morphology constrains the location of particle acceleration and requires an abrupt deceleration of the jet flow. We infer the presence of shocks on either side of the binary system at distances of 25 to 30 parsecs and conclude that self-collimation of the precessing jets forms the shocks, which then efficiently accelerate electrons
Functional structure of the natural enemy community of the fall armyworm, Spodoptera frugiperda in the Americas.
Get PDFJournal Articles. Unit for Environmental Sciences and Management, North-West University, PotchefstroomEcosystem functions such as biological pest control are mediated by the richness and abundance of service providers i.e., biological control agents (BCAs), relative contributions of individual taxa and community structure. This is especially relevant in the native range of agricultural herbivores, where a speciose community of co- evolved BCAs can prevent them from attaining pest status. Here, we use a powerful graphical approach to assess the functional structure of BCA communities of the fall armyworm (FAW) Spodoptera frugiperda (Lepidoptera: Noctuidae) on maize in the Neotropics. Drawing upon a curated database of all-time field and laboratory studies, we graphed patterns in the functional contribution, abundance and niche breadth for a respective 69, 53 and 3 taxa of resident parasitoids, predators and pathogens. Regardless of varying taxon coverage and rigor of the underlying studies, functional structure follows a saturating relationship in which the first three taxa account for 90–98% of aggregate biological control function. Abundance-functionality matrices prove critically incomplete, as more than 80% of invertebrate taxa miss empirically derived efficiency metrics while associated FAW infestation data are scarce. Despite its methodological shortfalls and data gaps, our work pinpoints Chelonus insularis, several taxa of egg parasitoids, Doru spp. and Orius spp. as taxa with outsized (average) functionality and conservation potential. This is also exemplified by the highly variable aggregate function across studies, with dispersion indices of 1.52 and 2.14 for invertebrate BCAs. Our work underlines the critical importance of functional ecology research, networked trials and standardized methodologies in advancing conservation logical control globally
Rural-Urban Fertility Disparity in The Gambia: Standardized Rate, Decomposition, Parity Progression, and Determinants
Get PDFJournal Article. Population and Health Research Entity, North-West University, MafikengThis cross-sectional design study examined rural-urban fertility differences in The Gambia. We used the 2019-20 Gambia Demographic and Health Survey data. A multi-stage sampling technique was used to select women of reproductive age (8,747 urban & 3,119 rural). Data were analyzed using descriptive statistics, Kitagawa’s Decomposition technique, and the negative binomial (NB) model, α = .05. The mean Children Ever Born (CEB) was higher in the rural (3.25 ± 3.02) than in the urban (2.19 ± 2.45) areas. In the urban and rural areas, 82.8% and 95.1% of women aged 45–49 years who had had three children progressed to fourth birth, respectively. The parity progression rate (λ) was lower in the urban (-0.0647) than in the rural (-0.051). The difference between the standardized fertility rates in rural and urban areas was 83.2 in The Gambia, and the effect of the age composition attributable to this difference was 8.11%. The fertility incidence rate ratio (IRR) was 44% (IRR = 1.440, 95% CI [1.371, 1.513], p < .001) higher in the rural than the urban areas. A similar pattern of rural-urban differences in fertility was observed in the full model. Childbearing progression was higher in rural areas than urban areas and rural-urban differences exist in fertility determinants in The Gambia. Thus, rural-urban-specific fertility reduction programs may address the observed fertility differences in the rural and urban areas in The Gambia
Protocol for a low-volume, direct analysis urine preparation procedure for non-targeted GC-MS metabolomics.
Get PDFJournal Article. Focus Area Human Metabolomics, North-West University, PotchefstroomWe present a low-volume, direct analysis protocol for non-targeted gas chromatography-mass spectrometry (GC-MS) metabolomics, using 100 μL of urine. The steps include sample collection, stock solution preparation, metabolite extraction, two-step derivation with a drying phase, and analysis via two-dimensional GC time-of-flight MS (GCxGC-TOFMS). This protocol improves the efficiency and thoroughness of urinary metabolite analysis, contributing to advancements in metabolomics research, disease diagnosis, and biomarker discovery. For complete details on the use and execution of this protocol, please refer to Olivier et al.
Deforestation amplifies climate change effects on warming and cloud level rise in African montane forests
Get PDFJournal Article, Faculty of Natural and Agricultural Science,North--West University-Potchefstroom CampusTropical montane forest ecosystems are pivotal for sustaining biodiversity and essential terrestrial ecosystem services, including the provision of high-quality fresh water. Nonetheless, the impact of montane deforestation and climate change on the capacity of forests to deliver ecosystem services is yet to be fully understood. In this study, we offer observational evidence demonstrating the response of air temperature and cloud base height to deforestation in African montane forests over the last two decades. Our findings reveal that approximately 18% (7.4 ± 0.5 million hectares) of Africa’s montane forests were lost between 2003 and 2022. This deforestation has led to a notable increase in maximum air temperature (1.37 ± 0.58 °C) and cloud base height (236 ± 87 metres), surpassing shifts attributed solely to climate change. Our results call for urgent attention to montane deforestation, as it poses serious threats to biodiversity, water supply, and ecosystem services in the tropics