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High prevalence of multidrug resistant and extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolated from urinary tract infections in the West region, Cameroon
Get PDFFunding: Dr Raspail Carrel Founou received funding from the Mérieux Institute, Lyon France for the CAREFOOD project. CAREFOOD project had supported all the molecular aspects of this study. Dr Luria Founou received funding from the Thrasher Research Fund through the Thrasher Early Career Award (Award number 01364). This work was also supported by the Research Institute of Centre of Expertise and Biological Diagnostic of Cameroon (CEDBCAM-RI).Background: Antimicrobial resistance remains a worldwide health problem with serious societal and economical repercussions. Multidrug resistant and Extended-Spectrum β-Lactamase producing-Enterobacterales (ESBL-E) are pathogens of critical public health priority that urgently require the research and development of new drugs. This study aims to determine the prevalence and characterize the genes conferring resistance to β-lactams among Escherichia coli and Klebsiella pneumoniae isolated from patients with urinary tract infections (UTIs) in the West region, Cameroon. Methods: A cross-sectional study was conducted among two healthcare facilities during a four-month period from February to May, 2023. All mid-stream urine samples were collected from UTIs patients. The Escherichia coli and K. pneumoniae strains were identified using Enterosystem 18R kit following the manufacturer's instructions. The antimicrobial susceptibility test (AST) was performed using the Kirby-Bauer disk diffusion method. The screening of ESBL production was done using ESBL ChromAgar medium combined with the double-disk synergy test (DDT). Antimicrobial resistance genes were detected using polymerase chain methods. The data analysis was performed using Excel 2016 and IBM SPSS version 20. Results: A total of 215 urine samples were collected and analyzed during the study period. A 31.62% (68/215) prevalence of Enterobacterales was detected with prevalence of 79.41% (54/68) and 14.70% (10/68) for Escherichia coli and Klebsiella pneumoniae respectively. The overall prevalence of ESBL-Enterobacterales was 64.70% (44/68). About 82% (36/44) of isolates were MDR and high resistance level was observed for amoxicillin + clavulanic acid and ceftazidime. The resistance genes detected were bla CTX-M, and bla TEM respectively. Conclusion: The findings of this study highlight the high burden of MDR and ESBL-E. coli and K. pneumoniae isolates from UTIs. The study emphasizes the necessity of routine screening and monitoring of antimicrobial resistance in healthcare facilities and community settings. It is therefore crucial to implement antimicrobial stewardship programs in the country and infection prevention and control (IPC) measures in hospital settings.Peer reviewe
A three-dimensional, multi-wavelength view and time-dependent analysis of the Milky Way's local ionized gas
Get PDFFunding: LM acknowledges financial support from a UK-STFC PhD studentship. DK acknowledges support from HST-AR-17060 provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of 389 Universities for Research in Astronomy, Inc., under NASA 390 contract NAS5-26555.This work is the continuation of a series attempting to characterize the local warm ionized medium through both static and time-dependent simulations. We build upon our three-dimensional, observationally derived simulation of the local photoionized interstellar medium – based on static photoionization simulations constrained by 3D dust maps – to include metals required to predict collisionally excited optical and infrared emission lines, providing the first all-sky prediction of a series of lines including [S II] 6716 Å, [N II] 6584 Å, and [O III] 5007 Å. While these predictions only include O-star photoionization under ionization equilibrium, we also carry out a suite of radiation-hydrodynamics simulations including time-dependent metal ionization and the effects of supernova feedback to highlight missing features in our predicted skies. We use the simulations to estimate the very local (1 kpc2) Galactic star formation rate, finding a rate of 370 M☉ Myr−1 kpc−2 provides the best match between the observationally derived and ab initio simulations. This is approximately a factor of 4 lower than previous estimates for the star formation rate required to support an observed layer of high-altitude diffuse ionized gas, possibly suggesting a ‘bursty’ star formation history in the region surrounding the Sun. We also investigate the effects of O-star environments on their ability to ionize large volumes of diffuse ionized gas, and find it is likely ionized by a small number of luminous O stars located in regions where the leakage of their Lyman continuum photons can produce the vast volumes of ionized gas observed in the mid-plane and at high galactic altitudes.Peer reviewe
Genetics of human handedness : microtubules and beyond
Get PDFHandedness (i.e., the preference to use either the left or the right hand for fine motor tasks) is a widely investigated trait. Handedness heritability is consistently estimated to be 25%. After decades of research, recent large-scale genome-wide association and exome sequencing studies have identified multiple genes associated with handedness and highlighted tubulin genes. Tubulin genes play a role in several processes during brain development that may be relevant for handedness ontogenesis, including axon guidance, axon growth, and forming the inner structure of motile cilia. Moreover, tubulin genes are associated with several psychiatric disorders. This finding therefore may offer insights into biological pathways mediating the link between handedness, brain asymmetries, and psychiatric traits.Peer reviewe
Timing of calcification and environmental variability determine pH proxy fidelity in coastal calcifying macroalgae
Get PDFFunding: Natural Environment Research Council (Grant Numbers NE/L002590 and NE/L002590/1), Marine Alliance for Science and Technology for Scotland, Scottish Alliance for Geoscience Environment and Society small grant schemes.Long-lived calcifying marine biota are increasingly used as paleo-archives for reconstructing ocean pH. They enable exploration of the rate and magnitude of ocean acidification in shallow-water ecosystems serving as proxies for environmental pH reconstruction. However, shallow water systems often have highly variable carbonate chemistry, and the impact of this on the accuracy of pH reconstructions from long-lived marine calcifiers is not known. In particular, a better understanding of the timing of calcification with respect to environmental pH cyclicity is needed. To test the fidelity of coastal environmental pH proxies, we assessed the synchronicity between calcification and in situ diel carbonate chemistry in a tropical (One Tree Island, Great Barrier Reef, Australia) and a temperate (Loch Sween, Scotland) location using calcifying macroalgae (rhodolith-forming coralline algae) as a model system. Calcification occurred primarily during daylight hours, meaning a recording bias was introduced when compared to the full diel pH range (< 0.02 pH units). This bias resulted in pH offsets up to 0.043 pH units over the period 1860–2020, representing up to 34% of the projected pH change from 1860 in the tropics and up to 1.8% in temperate latitudes. Therefore, when proxy records are used to extend modern instrumental records of pH, we find that this may lead to bias, indicating daytime, nighttime, and full diel pH records should be assessed separately. We suggest that temporal pH cycles should be characterized at a local scale to enable incorporation of potential biases in the application of calcifying marine macroalgae to reconstruct pH change.Peer reviewe
Host–guest engineering of MOF-808 for random lasing and solid-state emission
Get PDFFunding: We thank the LaBAM group for scientific discussions. This work was supported by the European Research Council grant ADOR (Advanced Grant 787073). The authors acknowledge the EPSRC Light Element Analysis Facility Grant (EP/T019298/1) and the EPSRC Strategic Equipment Resource Grant (EP/R023751/1).Fluorescent organic dyes have a broad range of applications across various fields. However, their use is threatened by stability issues such as photobleaching and aggregation-caused quenching that prevent them from showing solid-state luminescence and being used in high-power photonics applications for a long period. One possibility to overcome these problems is to embed dye molecules within a hosting platform. Metal–organic frameworks (MOFs) are among the best candidates to overcome these problems due to their porous nature, which provides excellent sorption capacities while ensuring stability for potential guest molecules, even in extreme environments. In this work, we investigate the optical performance of rhodamine B and coumarin 343 when interacting with Zr-based MOF-808. On one hand, we demonstrate that inclusion of dye molecules in MOF-808 cavities prevents aggregation-induced quenching, enabling the use of dyes in powdered form and enhancing their emission in solid-state applications, such as fingerprint detection. On the other hand, the dye–MOF interaction in solution reveals that MOF-808 nanoparticles act as efficient scatterers, significantly enhancing random lasing emission by narrowing the emission spectra and reducing the lasing threshold. The lasing performance is shown to be dependent on the MOF concentration and excitation intensity, with an optimal concentration minimizing the threshold and bandwidth. Finally, we demonstrate the feasibility of combining MOF-808 nanoparticles and dyes into polymeric thin films, where the MOFs contribute to halving the lasing threshold, making the system suitable for portable lasing applications.Peer reviewe
Cardiac safety of bedaquiline, delamanid and moxifloxacin co-administered with or without varying doses of sutezolid or delpazolid for the treatment of drug-susceptible TB
Get PDFFunding: This study was conducted by the PanACEA consortium, funded by the EDCTP2 programme (grant number TRIA2015-1102) with support from the German Ministry for Education and Research (BMBF; 01KA1701); further funding was contributed by the German Center for Infection Research (DZIF), the Swiss State Secretariat for Education, Research, and Innovation (SERI) and Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO). Otsuka provided delamanid for these studies at no cost to the consortium.Introduction: Many drugs for the treatment of TB prolong the QTc interval, which is associated with an increased risk of developing a life-threatening arrhythmia known as torsades de pointes. Sutezolid and delpazolid are novel oxazolidinones with demonstrated bactericidal activity. We aimed to assess the effects of sutezolid or delpazolid co-administered with bedaquiline, delamanid and moxifloxacin on the QTcF interval (Fridericia’s correction). Furthermore, we developed a population pharmacodynamic model to assess the effects of drug exposure on the QTcTBT interval (TB-specific correction). Methods: Participants were randomized to receive standard-dose bedaquiline, delamanid and moxifloxacin with varying doses of either sutezolid (no sutezolid, 600 mg daily, 1200 mg daily, 600 mg twice daily, 800 mg twice daily) or delpazolid (no delpazolid, 400 mg daily, 800 mg daily, 1200 mg daily, 800 mg twice daily). The QTc interval was determined using weekly ECG assessments. Results: Data from 149 participants, yielding 2373 ECG observations were available for analysis. Nine participants (6.0%) experienced a Grade 3 QTcF prolongation as defined by the Common Terminology Criteria for Adverse Events v5.0. The population pharmacodynamic model predicted a 13.2 ms (95% CI: 10.9–15.3) increase of the QTcTBT in the first week of treatment, but no further increase after that. The exposure of bedaquiline’s M2 metabolite was found to drive part of the QTcTBT. No exposure–response relationship was identified for the other drugs investigated. Conclusions: The drug regimens containing standard doses of bedaquiline, delamanid and moxifloxacin, and varying doses of sutezolid or delpazolid were not found to pose a high cardiac risk in a population without further QTc-relevant risk factors. However, close monitoring of the QTc interval remains essential in patients with TB treated with combination drug therapy with known QTc-prolonging drugs.Peer reviewe
Exploring the dark side of continuous social media brand community participation on consumer psychological ill-being: initial vs sustained participation
Get PDFPurpose This study explores the dark side effects of continuous social media brand community (SMBC) participation on consumer psychological ill-being. Design/methodology/approach A two-wave online quantitative survey was conducted over a 12-month period, involving 805 consumers with prior experience participating in social media brand communities. The proposed model was analyzed using structural equation modeling (SEM) with AMOS 26.0. Findings The research indicates that individuals using social media for escapism are significantly linked to their SMBC participation and the experience of social media fatigue. Over time, participation in SMBC was found to greatly influence both social media fatigue and information overload. Notably, while negative emotions were closely tied to consumer psychological ill-being, information overload did not exhibit the same connection. Additionally, social media fatigue served as a mediator between SMBC participation and negative emotions. Similarly, negative emotions acted as a mediator between social media fatigue and psychological ill-being. Research limitations/implications This research examined the dark side of using social media as an escape and continuous participation in SMBC, employing a two-wave quantitative methodology. The study was confined to brand communities on the Facebook platform. This presents a limitation in terms of the broade applicability of the findings, as the analysis did not encompass a comprehensive range of social media platforms. Practical implications The study highlights the importance of managers maintaining order and promoting an environment of fairness on social media platforms to minimize negative emotions and reduce tensions among users. Additionally, governments can collaborate with social marketing agencies and NGOs to raise awareness about the potential adverse effects of excessive social media use, particularly focusing on protecting young people who are more susceptible to its negative impacts. Originality/value This research stands out as one of the few studies examining the potential negative aspects of SMBC activities, offering a meaningful addition to the existing body of literature on SMBC and psychological ill-being. Grounded in the theory of compensatory Internet use and the stressor-strain-outcome model, it provides valuable insights into the darker side of consumer social media escapism and participation in SMBCs, particularly in relation to their psychological ill-being.Peer reviewe
Can you remember what it was like to be a bat? : The knowledge argument, memory, and reincarnation
Get PDFIn most traditions within classical Indian philosophy, the soteriological goal of liberation from material existence has caused difficulties with introducing their systems of thought into contemporary discussions of physicalism. Despite this, scholars are finding ways for these traditions to contribute to discussions of physicalism. I shall continue this endeavour in this paper with the doctrine of reincarnation. I shall outline the implications of reincarnation for Thomas Nagel’s knowledge argument. After outlining some accounts of reincarnation and explaining Nagel’s argument, I shall argue that cases in which humans have past animal lives can be used as a way of refuting Nagel’s argument. I shall then develop two responses to the physicalist and will conclude that the second in particular undermines their use of reincarnation to defend their view against Nagel’s argument.Peer reviewe
From water to land : a review on the applications of environmental DNA and invertebrate-derived DNA for monitoring terrestrial and semi-aquatic mammals
Get PDF1. Terrestrial and semi-aquatic mammals are facing increasing threats globally, highlighting the need for reliable data on species' occurrence, distribution, and abundance for effective conservation efforts. However, obtaining reliable and robust information over broad spatial and temporal scales remains a significant challenge. 2. Environmental DNA (eDNA) and invertebrate-derived DNA (iDNA) applications have emerged as powerful surveying methods, with the potential to revolutionise ecological monitoring by improving species detections and providing better insights into mammalian distribution and diversity. While eDNA relies on genetic material shed by species into their surroundings, iDNA leverages DNA from invertebrates that interact with mammals. Both approaches offer a cost-effective means to obtain species records and community diversity metrics. 3. This review explores global applications of e/iDNA for surveying terrestrial and semi-aquatic mammals. By providing a comprehensive overview of the applications, sampling design, challenges, and prospects, this review serves as a guide to researchers and conservationists seeking to use eDNA for mammalian conservation efforts. 4. By evaluating the current state of e/iDNA applications, this review identifies the challenges and milestones that need to be addressed for these methods to become a practical method for monitoring mammals on a global scale. It highlights the need for further research to enhance the sensitivity and reliability of e/iDNA detections, standardisation of methodologies, and validation through comparison with traditional monitoring methods. This review sheds light on the potential of e/iDNA as valuable tools for aiding mammal conservation and inspiring future research and advancements in this field.Peer reviewe
The diverse quenching pathways of post-starburst galaxies in SDSS-IV MaNGA
Get PDFFunding: HL and ACC acknowledge support from a UK Research and Innovation (UKRI) Frontier Research Guarantee grant (PI Carnall; grant reference EP/Y037065/1). VW acknowledges Science and Technologies Facilities Council (STFC) grants ST/V000861/1 and ST/Y00275X/1, and Leverhulme Research Fellowship RF-2024-589/4. YMC acknowledges support by the National Natural Science Foundation of China, NSFC Grant Nos. 12333002.The quenching of star formation in galaxies is an important aspect of galaxy evolution, but the physical mechanisms that drive it are still not understood. Measuring the spatial distribution of quenching can help determine these mechanisms. We present the star formation histories (SFHs) and stellar metallicity evolution of rapidly quenched regions in 86 local post-starburst (PSB) galaxies from the Mapping Nearby Galaxies at APO (MaNGA) integral field survey, obtained through Bayesian full spectral fitting of their rest-frame optical spectra. We found that regardless of spatial location, the PSB regions have similar past SFHs and chemical evolution, once radial metallicity gradients are accounted for. This suggests that all PSB regions are regulated by a common set of local scale processes in the interstellar medium, regardless of the broader triggering mechanism. We show that the centres of galaxies with outer PSB regions are also quenching. The central specific star formation rate has declined by ∼1.0 dex on average during the last 2 Gyr, a significantly steeper decline than main sequence galaxies over the same period (≈0.2 dex). This central quenching can be either synchronous, outside-in or inside-out, and slower or as fast as the outer regions, highlighting the diversity of quenching pathways for local galaxies. Our results imply a primary quenching mechanism that is both catastrophic and global in rapidly halting star formation in local galaxies. We suggest the predominant cause is galaxy mergers or interactions, with large scale feedback from a starburst or a central supermassive black hole playing a lesser role.Peer reviewe
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