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Antibiotics

MDPI AG

Preprints posted in the last 7 days, ranked by how well they match Antibiotics's content profile, based on 34 papers previously published here. The average preprint has a 0.04% match score for this journal, so anything above that is already an above-average fit.

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Comparative genomics of clinical isolates of Pseudomonas aeruginosa from cystic fibrosis patients in Mexico

Martinez-Rosales, E.; Geronimo-Gallegos, A.; Cuevas Schacht, F.; Lozano Gamboa, M. S.; Lopez-Lopez, M.; Garcia-Contreras, R.; Coria-Jimenez, R.; Ceapa, C. D.

2026-09-01 microbiology 10.64898/2026.08.28.747926 medRxiv
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Pseudomonas aeruginosa (P. aeruginosa) is the primary pathogen responsible for morbidity and mortality in patients with cystic fibrosis (CF). Its genomic plasticity and constant selective pressure from antimicrobial treatments have favored the emergence of multidrug-resistant clones. This study conducted a comparative genomic analysis of 41 P. aeruginosa isolated from pediatric patients with CF in Mexico from 2015 to 2024, with the aim of characterizing their evolutionary dynamics, resistome, and virulome. Whole-genome sequencing (MGI, Illumina, and PacBio platforms) was used, with de novo assemblies performed using Unicycler v0.4.8 on the BV-BRC platform. The databases used for the resistome were CARD and NDARO, and for the virulome, VFDB. Phylogenetic reconstruction was based on core-genome alignments generated with Roary v3.13.0, with maximum likelihood reconstruction performed in IQ-TREE v2.1.2. The statistical significance of the segregation of resistance and virulence patterns was evaluated using PERMANOVA analysis. The results revealed a significant clonal prevalence of sequence types (ST) 307 and ST 167. Phylogenomic analysis grouped the isolates into three main clades; Clade 1 stood out for having the highest resistance gene load (mean of 75 genes/genome), establishing itself as the main reservoir of multidrug-resistant profiles. Genotype-phenotype concordance reached 65.5% overall, with high accuracy for aminoglycosides (87.8%) and fluoroquinolones (82.9%). Furthermore, virulome analysis identified 67 distinct patterns that were significantly segregated among the clades (PERMANOVA: R2=0.31, p=0.001). These findings demonstrate that the evolution of P. aeruginosa lineages in the pediatric clinical setting involves parallel and coordinated adaptations in both their resistance potential and their virulence arsenal. This study underscores the need to adopt a multidisciplinary approach to the clinical management of chronic P. aeruginosa infections in pediatric patients. The persistence of extensively drug-resistant (XDR) strains calls for the integration of genomic surveillance and functional diagnostics, as well as the search for therapeutic alternatives for the clinical management of patients with cystic fibrosis.

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INTerrupting prolifERation of Carbapenem resistance in Indonesia: clinical and genomic Evaluation of Pathways of Transmission (INTERCEPT) : a Study Protocol

Farida, H.; Hapsari, R.; Lestari, E. S.; Farhanah, N.; Roberts, A. P.; Graf, F. E.; Dacombe, R. E.; Moore, M. E.; Lewis, J. M.

2026-08-31 infectious diseases 10.64898/2026.08.28.26361608 medRxiv
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Background Carbapenem-resistant bacteria are a major global public health threat, classified as critical priority pathogens by the WHO. In Indonesia, despite a national antimicrobial resistance control programme established by the Ministry of Health in 2015, resistance rates continue to rise, including increasing carbapenem resistance among clinically important bacteria. Strengthening approaches to directly interrupt transmission is essential, yet transmission pathways remain poorly understood with limited research and policy guidance within the Indonesian context. Methods and analysis The INTERCEPT study is a UK-Indonesia multidisciplinary collaboration aiming to identify transmission routes of carbapenem-resistant bacteria across healthcare and community settings, and the mechanisms of resistance gene transfer between bacteria and mobile genetic elementss. We will conduct genomic surveillance of hospital inpatients, healthcare workers, hospital environments, and surrounding communities, including wastewater systems, combined with genomic analyses and mathematical transmission modelling. A cohort of patients with bloodstream infections will be recruited to evaluate resistant bacteria, treatment practices, and clinical outcomes. Qualitative research will explore behavioural and system-level factors influencing transmission and intervention implementation. Findings will inform stakeholder workshops to co-design context-specific interventions, with pilot intervention over 9 months with pre- and post-intervention assessment to guide scalable strategies to reduce AMR transmission. Discussion The INTERCEPT study addresses carbapenem resistance in Indonesia using an integrated approach combining microbiological surveillance, genomics, modelling, and qualitative methods. Strengths include cross-sectoral analysis (patients, workers, environment) and participatory intervention design. Limitations include geographic scope restricted to Central Java, Indonesia.

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Effect of Mushroom-Bacteria Co-culture on Mushroom Growth and Antimicrobial Properties

Wang, E.; Cavanaugh, N. T.; He, Y.; Chai, Y.

2026-08-31 microbiology 10.64898/2026.08.30.747672 medRxiv
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Edible mushrooms have been reported to have antimicrobial properties and other health benefits. This study aims to test the antimicrobial activities of several edible mushrooms from markets and test if co-culturing them with bacteria could induce stronger anti-bacterial properties. Commercial mushrooms, Hericium erinaceus (lions mane), Pleurotus ostreatus (oyster mushroom), Lentinula edodes (Shiitake) and Agaricus bisporus (button mushroom), were grown from strictly controlled/sterile substrates. Ethanol and water extracts from the mushrooms were prepared and tested against the bacteria Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis, and the fungus Candida albicans for antimicrobial activities. Shiitake water extract (SWE) showed strong antibacterial effects against all tested bacterial species, inhibitory effects on their biofilms, and antifungal activity. The antimicrobials in SWE seem to damage the cell wall and cell membrane of the bacteria, prefer weak acidic conditions, and are heat labile. Some antimicrobials are likely proteins and polysaccharides. In contrast, 3 other mushrooms displayed only weak antimicrobial effects. The fast-growing lions mane and oyster mushroom were co-cultured with different bacteria. The co-cultivation promoted the fruiting body development of lions mane. Co-culturing with S. aureus increased the anti-bacterial effects of lions mane against S. aureus, E. coli and particularly B. subtilis. Co-culturing the oyster mushroom with bacteria, especially B. subtilis and P. aeruginosa, boosted the mushroom growth. All tested bacteria, especially S. aureus, increased oyster mushroom anti-bacterial effect against E. coli and B. subtilis. The findings indicate that mushroom-bacteria co-culturing could have benefits both agriculturally and medicinally.

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Best Practice Manufacturing and Quality Standards for Bacteriophage Therapy Products: Australian Consensus Statements

Watts, K.; Lin, R. C.; Lynch, S.; Warning, J.; Barr, J. J.; Ben Zakour, N.; Campbell, A.; Chan, J.; Collie, L.; Hedges, M.; Hudson, B.; Irwin, A.; Khatami, A.; Kicic, A.; Laucirica, D.; Lauter, C.; Ling, K.-m.; Ng, R.; Pavuk, N.; Rahmatullah, R.; Sinclair, H.; Tucker, E.; Vreugde, S.; Warner, M.; Velickovic, Z.; iredell, j.

2026-08-31 public and global health 10.64898/2026.08.26.26361487 medRxiv
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Objective As antimicrobial resistance (AMR) continues to threaten global public health, bacteriophage therapy products (BTPs) offer a promising alternative to conventional antimicrobials. However, translation into routine clinical practice requires best practice standards for manufacturing and quality control to ensure the consistent safety, quality, and reliability of personalised BTPs produced for individual patients or small cohorts. Design A modified Delphi methodology was used to develop consensus statements, engaging experts from Australia's National Bacteriophage Therapy Regulatory Working Group across the fields of clinical microbiology, phage biology, good manufacturing practice (GMP), regulatory science, and government. The process comprised three iterative phases: (1) structured statement development, (2) an anonymous REDCap survey, and (3) a hybrid consensus meeting. The strength of evidence and recommendations was assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework. Results Consensus was reached on 35 statements to provide best practice manufacture and quality control guidance for BTPs. These statements address requirements for phage identification and characterisation; define the point at which GMP-aligned processes commence for ubiquitous phages; outline quality control expectations for phage active pharmaceutical ingredient (pAPI) production and maintenance of BTP and host cell repositories. Additional guidance covers quality management systems, including documentation, traceability, and governance. Conclusion These consensus statements provide comprehensive best practice recommendations for the manufacture and quality control of BTPs in Australia. By promoting consistent, safe, and quality-assured approaches to personalised BTPs, they aim to facilitate clinical implementation while remaining aligned with existing international pharmacopoeial standards and regulatory frameworks.

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Clinical evaluation of artificial intelligence for diagnostics of antibiotic-resistant bacteria

Hessel, M.; Inda Diaz, J. S.; Sjöberg, A.; Salva-Serra, F.; Helldal, L.; Jirstrand, M.; Johnning, A.; Kristiansson, E.; Skovbjerg, S.

2026-08-31 infectious diseases 10.64898/2026.08.27.26361401 medRxiv
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Antimicrobial resistance is a public health challenge, driving the need for rapid, cost-effective diagnostic support tools. Artificial intelligence (AI) may enable prediction of susceptibility to untested antibiotics from known susceptibility results, but prospective clinical validation is required before routine use. We evaluated an AI-based decision support method, trained on invasive isolates from the European Surveillance System (TESSy), for prediction of antibiotic susceptibility in clinical Escherichia coli urine isolates. The evaluation included 99 E. coli isolates from urine samples with diversity in age, sex, and antibiotic susceptibility. Predictions were evaluated for 14 antibiotics using patient metadata and susceptibility results for 4-8 antibiotics as input. Prediction uncertainty was handled using conformal prediction, allowing abstention when confidence was insufficient. EUCAST disk diffusion test results were used as reference and genomic sequence data was used to explore mechanisms of the AI performance. Without conformal prediction, 84% of predictions were correct when susceptibility results of six antibiotics were used to predict susceptibility to eight additional antibiotics. Across all predictions generated using susceptibility results for six antibiotics as input, the major and very major error rates were 19% and 12%, respectively. Prediction errors varied between antibiotics and were associated with certain phenotypic and genotypic resistance patterns. Conformal prediction reduced errors but increased abstentions; at confidence levels of 90%, 95%, and 97.5%, the model abstained in 9.6%, 14%, and 22% of instances. The method showed promising performance, but its clinical use remains limited and may require diagnostic data beyond susceptibility test results and demographic variables.

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Pharmacovigilance organization and training needs of health personnels in health facilities of Cameroon: a cross-sectional study

MURHABAZI BASHOMBWA, A.; TCHIO-NIGHIE, K. H.; NANA DJAPOU, M. C.; BUH NKUM, C.; BLAMA ABBA, I.; BEKOLO, C. E.; ATEUDJIEU, J.

2026-08-31 public and global health 10.64898/2026.08.26.26361382 medRxiv
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Health facilities (HFs) routinely administer medicines and are expected to ensure patient safety by detecting, reporting, investigating, and analysing adverse events following exposure to drugs (AEFED). This study aimed to assess the implementation of pharmacovigilance activities in referral and regional health facilities in Cameroon and to identify pharmacovigilance training needs among healthcare personnel (HP). This was a cross-sectional descriptive study targeting referral and regional health facilities and healthcare personnel involved in patient care and pharmacovigilance activities in Cameroon. Health facilities were selected using stratified purposive sampling, while healthcare personnel were selected through exhaustive sampling. Data were collected using semi-structured electronic questionnaires administered face-to-face by trained enumerators. The questionnaires assessed the organization, resources, and implementation of pharmacovigilance activities at health facilities, as well as healthcare personnel knowledge of pharmacovigilance concepts, previous training, and perceived training needs. Of the 14 eligible health facilities, 10 (71.4%) consented to participate in the study. Of the 10 health facilities, 4 (40.0%) had an established pharmacovigilance unit, while 3 (30.0%) reported conducting neither detection nor notification activities. Among the 261 healthcare personnel approached, 214 (81.9%) participated. Only 41.6% had needed knowledge to detect an adverse event, while 72.9% were aware of adverse event notification procedures. Previous exposure to pharmacovigilance training was reported by 37.9% of healthcare personnel, and all participants expressed a need for additional training, particularly on national pharmacovigilance regulations (69.2%), organization of the pharmacovigilance system (67.3%), and adverse event detection (67.3%). The main reported challenges by healthcare personnel in the implementation of pharmacovigilance activities included insufficient budget allocation, limited access to pharmacovigilance training, lack of pharmacovigilance guidelines and insufficient qualified human resources. Pharmacovigilance implementation in referral and regional health facilities in Cameroon remains limited, with gaps in organizational structures, resources, healthcare personnel knowledge, and training. Strengthening pharmacovigilance systems through improved facility capacity, availability of essential tools, and targeted healthcare personnel training is needed to enhance drug safety surveillance.

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Combined production of Non-Hemolytic Enterotoxin and Sphingomyelinase as a marker of diarrheal food poisoning strains in the Bacillus cereus group

de Freitas Cardoso, P.; Gilois, N.; Trinidade Vilas-Boas, G.; Lereclus, D.; Gohar, M.; Perchat, S.; Slamti, L.

2026-08-31 microbiology 10.64898/2026.08.27.747690 medRxiv
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The Bacillus cereus group comprises bacteria of biotechnological interest, but also raises health concerns. Some bacteria in this group are opportunistic human pathogens, mainly causing foodborne gastrointestinal infections. As of today, the presence, sequence variability, or expression of genes encoding toxins or other virulence factors are insufficient to predict the potential of a given isolate to cause the diarrheal form of the disease. To address this limitation, we developed a sandwich ELISA to quantify the NheA and Sphingomyelinase (SMase) proteins in culture supernatants to test them as markers of pathogenic potential. Application of the assay to a collection of B. cereus group isolates revealed that strains associated with food poisoning outbreaks produce significantly more NheA and SMase than those isolated from the environment or from commercial products. Statistical analyses show that the combined quantification of NheA and SMase provides robust discrimination between pathogenic and non-pathogenic (environmental and commercial) profiles. These results demonstrate that the quantitative assessment of both NheA and SMase production can serve as a reliable biomarker for distinguishing diarrheic food poisoning isolates from harmless strains.

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Antimicrobial resistance genomics across Africa: critical determinants, repository bias and regional coordination

Omani, R.; Maina, G. N.; Fasina, F. O.

2026-09-02 public and global health 10.64898/2026.08.31.26361859 medRxiv
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Public genomic repositories can support antimicrobial resistance (AMR) surveillance, but unequal sampling can bias interpretation. We characterised AMR determinants, multicountry genomic cluster overlap and surveillance gaps across Africa using an NCBI Pathogen Detection snapshot retrieved on 24 August 2026 for 55 African Union member states. Records were validated and deduplicated by BioSample, and complete AMRFinderPlus calls were summarised across five United Nations M49 subregions and eight overlapping regional economic communities (RECs). Country-pair cluster overlap was assessed using the Jaccard index, while project-based and composition-standardised sensitivity analyses evaluated repository bias. The dataset contained 86,829 unique BioSamples from 51 states; South Africa, Malawi and Kenya contributed 55.8%. Complete extended-spectrum {beta}-lactamase calls were detected in 21,513 isolates and carbapenemase calls in 4,642. blaCTX-M-15 dominated the ESBL profile, while NDM and OXA types predominated. Seventy clusters contained carbapenemase-positive isolates from at least two countries. A shared REC covered all participating countries in 38 clusters, while 32 crossed REC boundaries. Normalised country-pair overlap was low, with a maximum Jaccard index of 9.5%. Project balancing reduced the Northern African carbapenemase estimate from 32.3% to 17.9% and the Eastern African ESBL estimate from 36.9% to 12.5%. Public repositories identify determinants and clusters for investigation but do not estimate prevalence or transmission. AMR surveillance should combine national confirmation, regional institution-led investigation where countries share an REC, and continent-wide coordination through Africa CDC for cross-REC signals, supported by representative One Health sampling, standardised metadata and sustained African sequencing capacity.

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Evaluating GPT-4o Model Proficiency and Clinical Reasoning for Antimicrobial Stewardship in Dentistry

Dick, M.; Madathil, S.; Patel, A.; Kapoor, H. S.; Sharma, M.; D'Souza, Z.; Hameed, S.; Abu-Samak, M.; Najirad, A.; Dwairi, D.; Radaideh, O.; Nicolau, B.

2026-09-03 dentistry and oral medicine 10.64898/2026.09.01.26361980 medRxiv
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Objectives: Dentists prescribe approximately one in ten antibiotics worldwide, yet antimicrobial stewardship (AMS) remains underemphasized in dental education. Large language models (LLMs) may support AMS training, but their proficiency and clinical reasoning in this context remain unclear. We evaluated GPT-4o's accuracy and clinical reasoning on dental antibiotic prescribing questions, stratified by question difficulty. Methods: We assembled 125 multiple-choice questions on dental antibiotic prescribing from eight peer-reviewed studies (2017-2023). GPT-4o answered each question and generated a clinical justification. Accuracy was assessed against source-study answer keys and examined across difficulty quartiles. Justifications were evaluated using an adapted 12-axis human-evaluation framework assessing scientific consensus, extent and likelihood of harm, inappropriate and missing content, bias, and both correct and incorrect comprehension, retrieval, and reasoning. Prophylaxis-specific questions were analysed separately. Results: GPT-4o correctly answered 72% of questions. Accuracy remained relatively stable across difficulty quartiles (78%, 78%, 65%, 70%). Experts rated 95.4% of justifications positively across the 12 axes. Comprehension, retrieval, and reasoning each exceeded 96.2% positive ratings. Missing content was the main weakness (7.8%), and 7.1% of justifications showed a moderate-to-severe potential for harm. Performance on prophylaxis-specific questions (98.1%) exceeded non-prophylaxis questions (93.0%). Conclusions: GPT-4o demonstrated moderate-to-high proficiency and clinically defensible reasoning in dental antibiotic prescribing questions. However, residual risks indicate that it is not suitable for unsupervised clinical use but shows potential as a supervised AMS educational tool.

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Global research trends and emerging fronts in refractory and macrolide-resistant Mycoplasma pneumoniae pneumonia in children: a bibliometric analysis (2000 2025)

Li, D.; Chen, H.; Shen, C.

2026-08-31 infectious diseases 10.64898/2026.08.25.26361371 medRxiv
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Background: Refractory and macrolide-resistant Mycoplasma pneumoniae pneumonia (MPP) has emerged as a major challenge in pediatric respiratory medicine, amplified by the post-2023 resurgence. However, a systematic overview of the research landscape specific to treatment-refractory and drugresistant disease in children remains lacking. Methods: Research articles and reviews on pediatric refractory or macrolide-resistant MPP published between 2000 and 2025 were retrieved from OpenAlex using Boolean searches. After screening, 2,286 records were quantitatively analyzed for annual output, contributing countries/institutions, thematic clusters, and citation-burst dynamics using Python. Results: Annual publications grew exponentially, with a pronounced surge after 2023 (n=378 in 2025). China produced the highest volume (45.1%) but recorded fewer citations per publication than the US, Japan, and Canada. The literature resolved into four clusters: macrolide resistance/molecular basis, epidemiology, etiology/co-infection, and refractory disease management. Burst analysis showed an evolution from earlier fronts like 23S rRNA mutations and azithromycin to recent emerging trends like pandemic-related co-circulation, genotype surveillance, and co-infection. Conclusions: Research on pediatric refractory and resistant MPP is expanding rapidly, shifting in emphasis from etiologic descriptions toward resistance mechanisms and clinical management. Standardizing the treatment of macrolide-unresponsive disease and post-pandemic epidemiological surveillance represent the principal directions for future work. Keywords: Mycoplasma pneumoniae; children; macrolide resistance; refractory pneumonia; bibliometric analysis; research trends

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EcoEnamel: Development of a Gelatin-Pectin Film for S. mutans Inhibition and Enamel Preservation in an In Vitro Model

Merle, J. A.; Javelona, G.

2026-09-01 microbiology 10.64898/2026.08.18.745620 medRxiv
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Rinsing-dependent dental hygiene presents a significant public health challenge in water-scarce environments. This study investigated combinations of xylitol (Xyl), chitosan (Chi), glycyrrhizin (Gly), epigallocatechin gallate (EGCG), dicalcium phosphate (DCP), and nano-hydroxyapatite (nHA) on the primary bacteria behind dental caries, S. mutans. These combinations were assessed for markers of dental caries by biofilm reduction, bacterial killing, and acid buffering against S. mutans when applied to an in vitro simulated enamel model using glass bead surfaces for biofilm formation, and gene expression was subsequently examined via RT-qPCR. Separately, mineral retention was also quantified. The EGCG-DCP-Xyl film demonstrated the highest overall efficacy, achieving a significant reduction in biofilm concentration compared to the untreated control and performing similarly in magnitude to the positive toothpaste control. Dead fluorescence staining confirmed that the EGCG-DCP-Xyl film induced the highest rate of non-viable cells, followed by the Chi-Gly film and the Gly-Xyl film. During 10-day pH cycling, the EGCG-DCP-Xyl and DCP-Xyl formulations buffered pH the most, consistently maintaining mean pH levels safely above the demineralization threshold of pH 5.5. The EGCG-DCP-Xyl also optimized mineral stability with the highest retained calcium concentration, significantly outperforming the Chi-Xyl film. At the transcript level, the EGCG-DCP-Xyl film induced substantial downregulation of key virulence genes, yielding decreases in expression for glucosyltransferase B (gtfB), associated with biofilm synthesis, collagen-binding protein (cnm), associated with tissue invasion, and lactate dehydrogenase (ldh), associated with lactic acid production, compared to the untreated control, with effects comparable in magnitude to the positive toothpaste control. This research suggests that targeting bacterial pathways and mineral loss through a portable film may have potential for preventing dental caries, especially in environments where water is limited. However, additional studies are necessary to evaluate real-world effectiveness.

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Design and Validation of New Primers for Specific and Sensitive Real-time PCR Detection and Quantification of Seven Botulinum Encoding Genes (Serotype A-G) of Clostridium botulinum

Phan, P.-L.; Chu, H.-A.; Le, T.-T.; Le, P.-A.; Nguyen, H.-L. T.; Tran, M.-N. T.; Nguyen, T.-T.; Pham, Y.; Phan, T.-N.

2026-09-01 molecular biology 10.64898/2026.08.21.746353 medRxiv
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Botulinum neurotoxins (BoNTs) comprise a highly diverse group of seven serotypes (from A-G) and over 40 subtypes worldwide. Previous primer- and probe-based nucleic acid amplification tests (NAATs) for detection of BoNT encoding genes are challenged by high levels of nucleotide polymorphism both across and within subtypes. In this study, multiple BoNT gene sequences were aligned to identify highly conserved regions for the design of new primers that enable the detection of all seven serotypes under the same conditions. Specific primer sets were designed and validated using in silico, conventional and real-time PCR with constructed plasmids carrying the target fragments and spiked food matrices. The established procedure achieved highly specific and sensitive detection of BoNT serotypes A-G with sensitivity of 10 copies/reaction and a total turnaround time of approximately 1.5 hours. The procedure also eliminated the carryover PCR product by using uracil-N-glycosylase in combination with dUTP in the assay reaction mix. This study provides an alternative NAAT with higher coverage and compliments the traditional mouse bioassays in enhancing global botulism surveillance capabilities.

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A transition state-like acylenzyme conformation distinguishes carbapenemase activity in class A β-lactamases

Beer, M.; Spencer, J.; Mulholland, A. J.

2026-09-01 biochemistry 10.64898/2026.08.31.748333 medRxiv
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Carbapenems are the most potent {beta}-lactams, key antibiotics for healthcare-associated infections by Gram-negative bacteria and evade hydrolysis by most {beta}-lactamases, but are increasingly threatened by emergence of enzymes exhibiting hydrolytic activity towards them. Of the four recognised {beta}-lactamase subclasses, class A (active-site serine enzymes that hydrolyse {beta}-lactams via a covalent acylenzyme intermediate) is the most widely disseminated and, while the majority of such enzymes react with carbapenems to form long-lasting acylenzyme complexes, several possess carbapenem-hydrolyzing activity (carbapenemases). Here, we investigate the basis for these differences in a panel of class A {beta}-lactamases using molecular dynamics (MD) simulations of the respective acylenzyme complexes and tetrahedral intermediates (TI). The simulations reveal multiple features associated with catalytic activity across the spectrum of enzymes tested, including more extensive interactions of the carbapenem acylenzyme carbonyl and generally increased lifetimes of active site water molecules positioned for deacylation. Analysis of the dynamic trajectories shows carbapenemases to have reduced root mean-squared fluctuation (RMSF) differences between the acylenzyme and TI, that are not limited to the active site, indicating that the acylenzyme complex is pre-organised for reaction in carbapenemases but not in carbapenem-inhibited enzymes. Similarly, Principal Component Analysis (PCA) of acylenzyme and TI dynamics shows greater overlap between the two states in carbapenemases, providing further evidence for acylenzyme pre-organisation. Such simulations may represent an effective computational assay able to identify enzymes with carbapenemase activity at relatively modest computational cost.

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Soil Microbial and Biochemical Properties under Conservation Agriculture in rice-based cropping systems in lower Indo-Gangetic Plain of West Bengal

Singh, P.; Jaison, M.; Saha, N.; Dutta, S.; Sen, A.; Biswas, T.; Mandal, B.; Mukherjee, S.; Dash, B.; Sahu, B.; Patel, R.; Dasgupta, A.

2026-08-31 microbiology 10.64898/2026.08.31.748290 medRxiv
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Microbial and biochemical properties of soil respond quickly with management practices, than chemical and physical properties. Moreover, impact of conservation agriculture (CA) on soil microbial properties is limited to microbial enumeration, but its effect on soil enzyme and microbial activity is little documented. To address these problems soil enzyme activities [dehydrogenase (DHA), {beta}-glucosidase (BGA), acid phosphatase (AcP) and alkaline phosphatase (AlP) and fluoresceine diacetate (FDA)], microbial activites ((Nitrogen fixation (NFBAct), Phosphate solubilization (PSBAct) & Cellulolytic activities (CDBAct)), microbial biomass ((Soil microbial biomass carbon (SMBC) & soil microbial biomass nitrogen (SMBN)) and available nutrient were studied to evaluate biological soil health in alluvial soil of lower Indo-Gangetic plain (IGP) under CA. Field experiment was conducted in split plot design (SPD), under 3 cropping systems (RMCp: rice-maize-cowpea; RWGg: rice-wheat- green gram; RCfBr; rice-cauliflower- bororice/summer rice). Tillage operations (CT: conventional; MT: minimum and ZT: zero tillage) was main plot and residue application as sub plot treatments [(R0 (no residue), R50 (50% residue) and R100 (100% residue)], treatments were replicated thrice. Biological soil health index (BSHI) indicated that among different degree of CA, ZT (0.464) and (MT=0.441) and R100 (0.464) treatment showed better response. Among different cropping system RMCp (0.359) & RWGg (0.343) outperformed RCfBr (0.609) cropping system with respect to (wrt) microbial and biochemical properties of the soil. Results indicated that for restoring microbial and biochemical properties of soil CA can be used as sustainable practice to restore agro-ecosystem. Keywords: Conservation agriculture, Cropping systems, Soil enzyme, Soil microbial properties, Residue application, Tillage operations.

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Biochemical and Binding Characterization of a Riboflavin Analogue Tethered to Biotin

Marincean, S.; Smith, S. R.; Branscum, T.; Ratajczak, A.; Benore, M. A.

2026-08-31 biochemistry 10.64898/2026.08.29.748002 medRxiv
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The binding affinities of a chimeric analog of a riboflavin derivative linked to biotin, (6- (7,8-dimethyl-2,4-dioxo-3,4-dihydrobenzo[g]pteridin-10(2H)-yl)hexyl 5-((3aS,4S,6aR)-2- oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl)pentanoate), referred to as C6-Rf-biotin-tag, to the riboflavin binding retain or streptavidin are in the M range, 1.29 {+/-} 0.277 and 3.00 {+/-} 0.459, respectively. These values suggest that C6-Rf-biotin-tag has potential applications in diagnostic assay and labelling target flavin binding proteins. The C6-Rf-biotin-tag which was characterized with respect to physical and biochemical properties retains UV/Vis spectroscopic and fluorescence behavior similar to riboflavin.

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Female contraceptive cover duration for miltefosine-containing regimens for the treatment of women with leishmaniasis

Chu, W.-Y.; Alves, F.; Dorlo, T. P. C.

2026-09-02 infectious diseases 10.64898/2026.08.31.26360682 medRxiv
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Introduction Miltefosine is the only approved oral antileishmanial agent, but its use in women of childbearing potential (WOCBP) is restricted due to preclinical teratogenicity. Current labeling recommends contraception during treatment and for at least five months thereafter, based solely on its long terminal elimination half-life. This study re-evaluated the required contraceptive duration using an exposure margin-based approach. Methods Virtual populations were generated from anthropometric data of 382 Indian, 4,462 Eastern African, and 4,019 Brazilian WOCBP with leishmaniasis. Published population pharmacokinetic models were used to simulate miltefosine exposure following 14-42-day regimens for visceral leishmaniasis (VL), post-kala-azar dermal leishmaniasis (PKDL), and cutaneous leishmaniasis (CL). A developmental safety exposure threshold was derived from the rat no-observed-adverse-effect level (0.6 mg/kg/day for 10 days) and adjusted using a 10-fold safety margin. Contraceptive durations resulting in median residual post-contraception exposure (AUCEOC-{infty}) below this threshold were considered supportive of contraceptive discontinuation. Results The developmental safety exposure threshold was estimated at 2.5 mg{middle dot}day/L. Despite pharmacokinetic differences across geographical regions and disease manifestations, required minimum contraceptive durations were consistent: three months from treatment initiation for the 14-day regimen, four months for 21- and 28-day regimens, and five months for the 42-day regimen. For the 14-day regimen, a single dose of a long-acting injectable contraceptive administered at treatment initiation would provide sufficient coverage. Conclusion An exposure margin-based approach supports shorter contraceptive durations than current recommendations. For the 14-day VL regimen, three months of contraception may provide a practical alternative to current labeling.

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The effect of high-dose glucocorticoids on opioid consumption in the first 24 hours after elective hip and knee arthroplasty: A natural experiment study of 47,317 surgeries in Eastern Denmark

Laigaard, J.; Moeller, M. O.; Olsen, M. H.; Overgaard, S.; Mathiesen, O.; Karlsen, A. P. H.

2026-09-02 pain medicine 10.64898/2026.08.31.26361793 medRxiv
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Background: In Denmark, perioperative high-dose glucocorticoid treatment were step-wisely implemented for total hip arthroplasty (THA), total knee arthroplasty (TKA), and unicompartmental knee arthroplasty (UKA). We aimed to estimate the effect of a single high dose of glucocorticoids on opioid consumption following primary THA, TKA, and UKA. Methods: This was a prespecified analysis of a multicenter natural experiment using electronic health record data. We included elective THA, TKA, or UKA surgeries performed in Eastern Denmark from 2017-2025. At each center, surgeries before implementation of high-dose glucocorticoids served as controls, whereas surgeries after implementation comprised the intervention group. The primary outcome was the between-group difference in cumulative 0-24h opioid consumption, which included preemptive end-of-surgery doses. The predefined minimal important difference was set at 5 mg IV morphine equivalents. Secondary outcomes were maximum 0-10 numerical rating scale (NRS) pain score and incidence of opioid-related adverse events within 24 hours, hospital length of stay, and days alive and out of hospital at 30 days. Results: A total of 47,317 surgeries performed at nine centers were analyzed: 13,010 controls and 34,307 in the intervention group. During the study period, five centers implemented high-dose glucocorticoids for THA patients, two for TKA/UKA patients. High-dose glucocorticoids were administered to 6% of patients before implementation versus 92% after. High-dose glucocorticoids resulted in a mean reduction of 3.8 mg intravenous (IV) morphine equivalents (95% CI 3.3;4.3). The intervention also reduced the maximum 0-24h NRS pain score by 0.8 points (99% CI 0.7;0.9), but there was no difference in adverse events, length of stay, or days alive and out of hospital. Conclusions: Implementation of high-dose glucocorticoids reduced 0-24-hour opioid consumption by 3.8 mg IV morphine equivalents after elective hip and knee arthroplasty. This difference was below the prespecified minimal important difference threshold. Online registration: https://doi.org/10.1101/2025.11.11.25339982

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A novel vimentin-stabilizing urea compound MXC-017 ameliorates DSS-induced colitis and radiation enteropathy in mice

He, L.; Azizi, L.; Calderon, C.; Parker, T.; Seth, R.; Chen, X.; Ding, H.; Jung, M.; Pajonk, F.

2026-08-31 molecular biology 10.64898/2026.08.30.748104 medRxiv
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Ulcerative colitis (UC) and radiation enteropathy involve intestinal epithelial injury, barrier dysfunction, and inflammation, but effective treatments remain limited. This study evaluated MXC-017, a novel vimentin-targeting urea compound, in mouse models of dextran sulfate sodium (DSS)-induced colitis and radiation-induced enteropathy. Acute colitis was induced in C57BL/6 mice using 3.5% DSS for seven days, followed by regular water for seven days. Radiation enteropathy was induced by 13 Gy total abdominal irradiation. Mice received MXC-017 (150 mg/kg) or vehicle. Disease activity, intestinal permeability, inflammatory and epithelial markers, and histopathology were assessed. MXC-017's effects on cancer stem cell frequency, sphere formation, and migration were also examined in PC-3 and DU-145 prostate cancer cells. MXC-017 reduced DSS-induced colitis severity, accelerated weight recovery, lowered disease activity, partially preserved colon length, and restored barrier function. It also reduced proinflammatory cytokines, macrophage infiltration, epithelial injury, and goblet cell loss while preserving epithelial proliferation and markers of intestinal stem cell function and tight-junction integrity. Following irradiation, MXC-017 improved weight recovery, reduced intestinal permeability, preserved epithelial architecture, and partially mitigated villus shortening. Importantly, MXC-017 did not protect prostate cancer stem cells from radiation. Instead, it reduced stem cell frequency, sphere-forming capacity, and cancer cell migration. These findings support vimentin targeting with MXC-017 as a potential treatment for UC and radiation-induced intestinal toxicity and as an adjunct to radiotherapy for pelvic and abdominal malignancies.

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Vaginal Steaming Practices Among Women At Mulago Sti Clinic, Uganda: Prevalence, Lactobacilli Proportion Differences, And Associated Factors.

Kakai, D.; Twinamasiko, N.; Kigozi, E.; Namutale, R.; Mutesi, B. A.; Bagaya, J.; Akinyi, L.; Kajumbula, H.; Nakubulwa, S.

2026-09-01 obstetrics and gynecology 10.64898/2026.08.28.26361407 medRxiv
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Abstract Background: Vaginal steaming has gained popularity among women for reasons known best to them. However, the effects of vaginal steaming on vaginal lactobacilli levels remain poorly understood and understudied. This study investigated the prevalence, assessed differences in the presence of bacterial vaginosis (BV) among women who practiced vaginal steaming and those who do not and determined the factors associated with vaginal steaming among women attending Mulago Sexually Transmitted Infections (STI) clinic in Uganda. Methods: This study utilized a cross-sectional design to enroll 181 women aged 18 to 49 years who were systematically sampled at Mulago STI clinic. Interviews were conducted to obtain the demographic characteristics of the participants. Vaginal swabbing and Gram staining were done to attain lactobacilli counts by microscopy which were categorized using the Nugent score. Data were analyzed using Stata. The potential confounding effects of other variables on the relation between vaginal steaming and the presence of bacterial vaginosis as well as factors associated with vaginal steaming were assessed using modified Poisson regression. Results: Prevalence of vaginal steaming was 40.3%, (95% confidence interval (CI) 33.0% - 48.0%). There were 41.1% women who practiced vaginal steaming occasionally, 53.4% who used hot water having herbs and 78.1% who practiced vaginal steaming for medical reasons. There was no difference in the presence of bacterial vaginosis when women who practiced vaginal steaming were compared to those who did not (p-value = 0.286). Factors that were significantly associated with vaginal steaming included having experienced vaginal issues (aPR = 0.07, 95% CI 0.01 - 0.12, p value = < 0.001) and contraceptive use (aPR= 0.52, 95% CI 0.37 - 0.72, p value = 0.001). Conclusions: About 2 in every 5 women at Mulago STI clinic reported to have indulged in vaginal steaming. There was no difference in the presence of bacterial vaginosis when women who practiced vaginal steaming were compared to those who did not. Having experienced vaginal issues and contraceptive use were significantly associated with vaginal steaming among women at Mulago STI clinic, Uganda. The Ministry of Health of Uganda should establish targeted screening and treatment for bacterial vaginosis alongside other sexually transmitted infections.

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Workforce Cost Absorption among Community Health Promoters in Fragmented Maternal Nutrition and Social Protection Systems: A Qualitative Study Across Three Kenyan Settings

SIVA, F. M.; Nyatuka, D.; de la Harpe, R.

2026-09-01 primary care research 10.64898/2026.08.26.26361384 medRxiv
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Community Health Promoters (CHPs) connect households with formal health services. In maternal nutrition, they provide counselling, follow-up and referrals. However, pregnant women experiencing poverty, food insecurity, and socio-cultural issues in resource-constrained settings may be unable to act on nutritional advice. While social protection could alleviate such socioeconomic issues, maternal nutrition and social safety nets operate in institutional silos, creating gaps that systematically exclude vulnerable mothers from essential relief. This qualitative study examines how CHPs navigate these gaps across three underserved Kenyan settings. We analysed semi-structured interviews of 12 purposively selected CHPs from a broader study of 75 stakeholders, using the Braun and Clarke thematic analysis framework. CHPs described recurrent gaps between household needs and resources available through formal maternal health, nutrition, and social protection systems. CHPs stepped in; extending follow-up care, brokering information, negotiating access, and spending personal resources with inadequate formal mechanisms. They experienced emotional and relational pressure from community mistrust, cultural limitations, administrative gatekeeping, digital-system failures, heavy workloads, and performance targets tied to unreliable pay. These insights reveal that CHPs act as invisible safety nets for fragmented services, taking on burdens that official programs overlook. We describe this as workforce cost absorption. Recognising this hidden contribution is important for workforce planning and for designing integrated maternal nutrition and social protection programs.