Antibiotics

BackgroundVirtual colony count is a kinetic, 96-well turbidimetric assay that has been used since 2003 to determine the antimicrobial activity of antimicrobial peptides including the defensin HNP1. Virtual colony count results differed from traditional colony counting results in studies of the antimicrobial activity of the human cathelicidin LL-37 and related peptides. The difference could possibly have been caused by an inoculum effect. MethodsThe virtual colony count assay was conducted using inocula that varied from 1250 to 1x108 virtual colony forming units (CFUv) per milliliter. ResultsThe virtual colony count assay demonstrated a pronounced inoculum effect of HNP1 against Staphylococcus aureus ATCC 29213, accompanied by biofilm formation observed in the wells of the 96 well plates at all inocula. The S. aureus inoculum effect was not as drastic as previously reported for Escherichia coli. ConclusionsThe inoculum effect is further evidence that biofilm formation is a resistance mechanism used by a variety of bacteria against antimicrobial peptides such as HNP1.

The inappropriate use of antimicrobials enhances antimicrobial resistance (AMR). Antimicrobial stewardship (AMS) is a coordinated effort of prescribers, pharmacists, and nurses. Still, local data regarding AMS-related knowledge, attitudes, and practices (KAP) are scarce in many low and middle-income countries. We evaluated KAP regarding AMS among the healthcare providers at Komfo Anokye Teaching Hospital (KATH), Ghana, and found the related factors. A cross-sectional survey in the form of a descriptive survey was conducted among medical doctors, pharmacists, and nurses at KATH. Knowledge, attitude, and practice were evaluated using a structured questionnaire. The scores were converted into percentages and classified as good (>=60%) or poor (<60%). Chi-square tests were used to test associations, and logistic regression to predict good KAP (p<0.05). A total of 349 healthcare professionals participated, which comprised: 91 medical doctors (26.1%), 101 pharmacists (28.9%), and 157 nurses (45.0%). The majority of the respondents had formal AMS/AMR training (69.6%), and 37.0% had updated training the previous year. Only 18.6% demonstrated good AMS-related knowledge, although attitudes were largely positive (95.7% good) and reported practices were mostly appropriate (77.4% good). In multivariable models, greater years of practice (5-9 years: adjusted odds ratio [AOR] 2.32; >=15 years: AOR 2.77) and formal training (AOR 2.94) were associated with good knowledge. Formal training was also associated with good attitudes (AOR 5.19). Compared with medical doctors, nurses had lower odds of good practice (AOR 0.29), while pharmacists had higher odds (AOR 1.41). Participants with 10-14 years of experience had higher odds of good practice (AOR 3.18). This study revealed that marked knowledge deficits exist, despite favourable attitudes and generally good self-reported AMS practices. Role-tailored, competency-based AMS training with regular updates and reinforcement through practical stewardship tools is needed to translate positive attitudes into evidence-based prescribing and administration behaviours.

Porcine Bacteroides thetaiotaomicron LYH5 demonstrated in vitro antimicrobial activity, suggesting probiotic potential. Due to poor gastric juice tolerance, LYH5 was encapsulated via extrusion using sodium alginate (SA) and gellan gum. Box-Behnken design optimization yielded optimal parameters: SA 1.5%, gellan gum 0.4%, CaCl2 0.9%, bacteria:glue ratio 1:4, achieving an encapsulation rate of 84.22{+/-}0.17%. Its effect on weaned piglet intestinal health was evaluated using 78 piglets (7.69{+/-}0.52 kg) randomly assigned to 4 groups for 40 days: CON (control), T (basal diet + LYH5 live bacteria, 1x10{superscript 1} CFU/mL), TJ (basal diet + LYH5 microcapsules, 1x10{superscript 1} CFU/mL, J (basal diet + empty capsules). The results of this experiment showed that compared with the control group, LYH5 microcapsule can improve the intestinal barrier function without affecting the growth performance of piglets, and provide ideas and references for the development of human next-generation probiotics (NGP). IMPORTANCEThis study addresses the key bottleneck of poor gastric acid tolerance of probiotics via microencapsulation and provides a practical reference for the development of human next-generation probiotics.

To make effective antimicrobial toothpastes, you need to optimize many parts that work together. Creating new formulations the old-fashioned way takes a lot of time and money. This research formulates and substantiates a methodological framework that combines systematic antimicrobial susceptibility testing with Particle Swarm Optimization (PSO) to enhance toothpaste formulations against clinically significant oral pathogens. Using a D-optimal mixture design, we made 24 different toothpaste formulations by changing the type of fluoride (NaF, MFP, SnF2), the concentration of fluoride (1000-1500 ppm), the concentration of SLS (0.5-2.5%), the type of abrasive (silica, calcium carbonate, dicalcium phosphate), and the concentration of abrasive (10-30%). We used agar well diffusion and minimum inhibitory concentration (MIC) tests to see how well the drugs worked against Streptococcus mutans ATCC 25175, Porphyromonas gingivalis ATCC 33277, and Lactobacillus acidophilus ATCC 4356. A Random Forest surrogate model was trained on 120 experimental data points (24 formulations x 5 concentrations) and validated through 10-fold cross-validation. Multi-objective PSO was used to improve the effectiveness of antimicrobials, the availability of fluoride, and the cost of the formulation. Chosen PSO-predicted formulations underwent experimental validation. The antimicrobial activity changed a lot (p < 0.001) depending on the formulation parameters. The optimized formulation (sodium fluoride 1120 ppm, SLS 2.3%, hydrated silica 18%, pH 7.2) showed 28.4 {+/-} 1.2 mm of inhibition against S. mutans, 26.8 {+/-} 1.4 mm against P. gingivalis, and 24.2 {+/-} 1.1 mm against L. acidophilus. These were improvements of 18.5%, 22.3%, and 19.8%, respectively, over the best commercial comparator. Experimental validation corroborated PSO predictions with a mean absolute error of 5.2%. Multi-objective Optimization found Pareto-optimal formulations that let you choose based on trade-offs between effectiveness, safety, and cost. Combining systematic experimental design with PSO gives a tested framework for making rational toothpaste formulations. This method significantly lowers the amount of work needed for experiments while also allowing for the Optimization of multiple competing formulation goals.

Phage therapeutics are re-emerging as adjuncts or alternatives to antibiotics and their clinical translation will be enhanced with production methods that minimise downstream processing. We evaluated whether an endotoxin-reduced E. coli strain developed for production of recombinant proteins, ClearColi(R), can serve as a useful, safe phage production host without compromising yield and whether targeted receptor complementation can expand its utility. The parent strain BL21(DE3), and its lipid A modified derivative, ClearColi(R), were compared with respect to infection and generation of phage. Across a panel of 31 phage, a similar host range was observed between BL21(DE3) and ClearColi(R). To expand host range ompC was genetically engineered into the chromosome of ClearColi(R), thereby adding OmpC-dependent phage to its production capacity. Production metrics were broadly comparable between the hosts; efficiency of plating and final titres for representative phage were not significantly different; burst size varied by phage but without consistent host bias. Endotoxin activity in ClearColi(R)-propagated lysates was reduced by over 1000-fold relative to BL21(DE3), reaching the low hundreds of endotoxin units (EU) versus hundreds of thousands for BL21(DE3). Intravesical administration of ClearColi(R)-derived phage (LUC4) into pigs elicited no clinical abnormalities and no significant increases in circulating cytokines up to 48 hours after administration. ClearColi(R) allows efficient production of diverse phage with low endotoxin, reducing the requirement for downstream processing. Although its minimal LPS reduces its capacity for producing some LPS-dependent phage and its growth is slower than BL21(DE3), requiring optimisation for maximal phage titre, the safety and simplified manufacturing process support further development of endotoxin modified strains for phage production. Impact statementAntibiotic resistance is a current global problem and treatments based on phage and phage products already have a proven track record with particular bacterial infections, especially in the urinary tract. While progress is being made on in vitro phage synthesis, large scale bacteriophage preparations require a bacterial host for production, consequently toxic components in the initial lysate need to be removed or significantly diluted for safe clinical use. This is a study of the potential to utilise an endotoxin-reduced E. coli strain, ClearColi(R), to produce safer phage therapeutics. Such endotoxin modified strains should minimise the processing steps required and reduce overall production costs of a phage preparation. The research demonstrates that the endotoxin-reduced strain was able to produce a wide range of phage and for studied examples at phage titres equivalent to the more toxic parent strain. We also show that the strain can be modified to increase its host range and confirm the very low endotoxicity of basic phage lysates produced by the strain. Replicating this process to engineer additional low-toxicity bacterial production strains will accelerate the development of safer, more cost-effective phage therapeutics.

AimsPseudomonas aeruginosa biofilm-associated infections pose a significant clinical challenge due to their inherent antibiotic tolerance. This study aimed to evaluate the antibacterial and antibiofilm activity of Placentrex, a standardised aqueous placental extract, against P. aeruginosa and to elucidate its molecular mechanism of action using RNA sequencing (RNA-seq). Methods and ResultsPlacentrex exhibited potent bactericidal activity against P. aeruginosa at 50 mg/mL. Biofilm formation was significantly inhibited by [~]87% at 50mg/mL after 72 hours. Preformed biofilms were eradicated by [~]93% and [~]89% at 50 and 25 mg/mL, respectively. Interestingly, biofilm viability was reduced by [~]93% and [~]87% upon treatment with 50 mg/mL and 25 mg/mL of Placentrex, respectively. EPS characterisation revealed that the EPS contain a single large polysaccharide, and chromatography data suggested that it is made up of glucose as a monomer. RNA-seq identified coordinated downregulation of seven key genes, namely, flp major pilin (surface attachment), extracellular solute binding protein (ABC transporter-mediated nutrient sensing and biofilm maintenance), gntP permease (carbon metabolism), AraC family transcriptional regulator (quorum sensing and polysaccharide biosynthesis), ureE (urease nickel metallochaperone), aromatic amino acid permease (pyoverdine and PQS biosynthesis), and MFS transporter (efflux and autoinducer export). ConclusionsPlacentrex exerts comprehensive antibiofilm and antibacterial activity through simultaneous disruption of surface attachment, nutrient-sensing-driven biofilm maintenance, quorum sensing, carbon metabolism, urease virulence maturation, and efflux-mediated persistence. This polypharmacological mechanism supports Placentrex as a promising multi-target antibacterial agent against P. aeruginosa biofilm-associated infections. Impact statementPlacentrex is a potential anti-biofilm agent against Pseudomonas aeruginosa.

Enteroaggregative Escherichia coli (EAEC) is a leading cause of persistent diarrhea in children in low- and middle-income countries, and the emergence of multidrug-resistant (MDR) strains necessitates non-antibiotic therapeutic strategies. This study evaluates Lactobacillus johnsonii, previously characterized by our group, as a probiotic candidate against a clinically confirmed MDR EAEC isolate resistant to ampicillin, ciprofloxacin, azithromycin, amoxicillin, and gentamicin. L. johnsonii demonstrated robust gastrointestinal resilience, high cell surface hydrophobicity, phenol tolerance, and rapid autoaggregation reaching 80.4 {+/-} 2.3% by 4 hours, collectively supporting mucosal colonization potential. In antimicrobial assays, L. johnsonii produced zones of inhibition against MDR EAEC substantially exceeding those of gentamicin, reduced viable biofilm-associated EAEC by over 80%, and displaced pre-adhered EAEC from HCT-116 intestinal epithelial cells in a time-dependent manner. L. johnsonii also attenuated MDR EAEC-induced gas production and reduced nitric oxide levels by 67.7% in infected RAW 264.7 macrophages, suggesting immunomodulatory activity. Nutrient competition did not appear to contribute to EAEC suppression under tested conditions, indicating inhibition is predominantly secretome-dependent. Fractionation of the L. johnsonii cell-free supernatant by fast protein liquid chromatography yielded five fractions below 75 kDa; fractions S5 and S6 exhibited sustained bactericidal activity at 6 hours. Gram staining confirmed that both fractions reduced viable EAEC cell numbers, with S6 producing a greater reduction than S5, indicating quantitatively distinct bactericidal potencies. These in vitro findings support the potential of L. johnsonii as a biotherapeutic candidate for antibiotic-resistant enteric infections. In vivo validation and chemical characterization of active fractions remain important next steps.

Background Antibiotic use is prevalent in hospitals, driving the emergence of drug-resistant pathogens. We investigated the contextual influences on antibiotic prescribing behaviour across hospitals in high, middle, and low-income countries in Asia with an aim to provide actionable insights to improve prescribing behaviour. Methods We conducted a large qualitative study across ten institutions in Singapore, Nepal, and Thailand. Semi-structured interviews and ethnographic observations involving physicians, nurses, pharmacists, and management staff were conducted. Data were analysed thematically using QSR NVivo 14. Findings A total of 194 interviews were conducted amongst physicians (54{middle dot}1%), nurses (19{middle dot}6%), pharmacists (12{middle dot}4%), and management staff (13{middle dot}9%). Structural factors such as limited microbiology laboratory capabilities, concerns about antibiotic quality, weak infection prevention and control policies, and the lack of relevant, updated guidelines were prominent drivers for prolonged and broad-spectrum antibiotics prescriptions. Where these system supports were in place, prescribing decisions were less defensive and more targeted, although prescriber responsibility and concerns about immediate patient deterioration continued to influence practice. Across settings, clinicians tended to prioritise short-term perceived benefits of antibiotic treatment over the longer-term risks of antimicrobial resistance.

Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is an important zoonotic pathogen that disrupts intestinal epithelial barrier integrity and induces excessive inflammatory responses, thereby leading to impaired growth performance and intestinal injury. EHEC is also an important cause Hemolytic Uremic Syndrome (HUS) in children and older adults. In pig production, chitosan is considered a promising alternative to antibiotics due to its bioadhesive and antimicrobial properties, but the effects and underlying mechanisms of chitosan (COS) under pathogenic challenge remain to be elucidated. One hundred and eight pigs were randomly divided into three treatments: an unchallenged control group (CON), an EHEC-challenged control group (ECON), and an EHEC-challenged group supplemented with 100 mg/kg COS (ECOS). Results show that EHEC challenge increased the feed conversion ratio (FCR), increased inflammatory cytokine levels, disrupted intestinal morphology, and downregulated tight junction and nutrient transporter gene expression (P<0.05). Dietary COS supplementation significantly improved average daily gain (ADG) and FCR during day 6-14 (P<0.05). Moreover, COS reduced fecal shedding of total E. coli (P = 0.085) and EHEC, attenuated systemic inflammation by decreasing serum TNF- and IL-6 levels, and enhanced humoral immunity as indicated by increased IgA and IgM concentrations (P<0.05). Importantly, COS alleviated EHEC-induced intestinal injury by restoring villus height and villus-to-crypt ratio, with enhanced mucosal digestive enzyme activities, and upregulated expression of tight junction proteins (ZO-1 and occludin) and nutrient transporters (SGLT-1 and PEPT1) (P<0.05). In conclusion, these findings indicate that dietary COS improves growth performance in EHEC-challenged weaned pigs, with enhanced intestinal barrier integrity and nutrient transport capacity.

Chronic wounds are persistent and difficult to treat. Often this is because they are colonized by polymicrobial communities which contribute to changes in antimicrobial susceptibilities, making these infections harder to effectively clear. We explored the role a community can play in individual members survival when challenged by antibiotics, specifically looking at a community consisting of Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis, and Acinetobacter baumannii. Our data shows that communities can contribute to both increases and decreases in susceptibilities depending on the species and the antibiotic. The changes in susceptibilities can be due to interspecies cooperation or competition, with identifiable mechanisms. We also demonstrated that current antimicrobial susceptibility testing (AST) methods used in hospitals, which focus on determining the minimum inhibitory concentration (MIC) via determination of visible turbidity breakpoints, are not able to truly indicate the clearance of bacteria, as species can persist in higher antibiotic concentrations after visible turbidity is gone. To combat decreases in antibiotic susceptibilities contributed to by the community, we used our data from individual antibiotics to determine a potentially effective antibiotic combination, similar to combinatorial therapy used in hospitals to treat recalcitrant infections. Our data proved useful, as the combination of gentamicin and cephalexin was able to overcome polymicrobial synergism and clear the desired bacteria. This demonstrates that it is possible to determine effective antibiotic treatments for polymicrobial infections, whether they be combinatorial in nature or not. One simply must account for the role of the community in order to prescribe the most effective treatment.

ObjectivesBiofilms are the dominant mode of bacterial life. The gut microbiota itself has characteristics of a biofilm that grows on the intestinal mucosa. C. difficile and VRE are commonly co-isolated from patients but biofilm formation has not been studied in a multi-species context. Here we study the interactions between C. difficile and VRE in surface adherent community. ResultsWe found that VRE inhibits C. difficile biofilm formation in dual-species culture in the presence of excess glucose. Robust dual-species biofilms were produced when the carbon source was changed to a non-fermentable sugar such as fucose and xylose. We observed a high level of vancomycin tolerance in C. difficile biofilms that was not affected by the presence of VRE. Finally we also found that a nutrient step-change is sufficient to induce dispersion of single and dual-species biofilms. ConclusionsVRE can inhibit the development of C. difficile biofilms in the presence of a fermentable carbon source. VRE does not appear to affect vancomycin tolerance or nutrient-induced dispersion of C. difficile biofilms. Highlights- VRE inhibits C. difficile biofilm formation in the presence of fermentable glucose. - Stable VRE - C. difficile biofilms are formed by managing the available carbon source. - VRE does not affect C. difficile vancomycin tolerance in this model. - A 10-fold increase in available nutrients is sufficient to induce biofilm dispersion in C. difficile and VRE.

BackgroundMetronidazole (MTZ) is a first-line antibiotic for several enteric infections. Its use is common in low-income countries, where most primary-care consultations are conducted by nurses. However, increasing resistance among some enteric pathogens is a growing concern. Using WHO guidelines, we conducted a register-based cross-sectional study to assess MTZ prescribing practices and their determinants in public and private primary healthcare facilities in South Benin. MethodsWe performed a register-based cross-sectional study covering the year 2020 in 11 primary healthcare facilities (5 public and 6 private) in Abomey-Calavi, South Benin, following WHO recommendations. In total, 200 visits per facility were selected using systematic random sampling. The primary outcome was the prevalence of MTZ prescription. Determinants of MTZ prescription were identified using multivariable logistic regression analysis. ResultsIn total, 2,200 medical visits were analyzed. The median age of patients was 19 years, and 57% were female. Antimalarials were prescribed in 52% of visits. Antibacterial agents were prescribed in the majority of visits, with MTZ being the second most frequently prescribed antibiotic (18%), after aminopenicillins (27%). In multivariable analysis, digestive symptoms (adjusted odds ratio [aOR], 8.65; 95% confidence interval [CI], 6.49-11.6), genitourinary symptoms (aOR, 6.84; 95% CI, 3.18-15.0), and skin lesions (aOR, 2.39; 95% CI, 1.58-3.60) were independently associated with increased odds of MTZ prescription. In contrast, fever (aOR, 0.66; 95% CI, 0.49-0.87), respiratory symptoms (aOR, 0.44; 95% CI, 0.26-0.71), and malaria (aOR, 0.21; 95% CI, 0.15-0.28) were associated with decreased odds. Visits in the private sector were also associated with higher odds of MTZ prescription compared with the public sector (aOR, 2.31; 95% CI, 1.78-3.02). ConclusionMTZ is the second most commonly prescribed antibiotic in primary care in the study area, with its use largely driven by digestive symptoms. Further studies are needed to assess the appropriateness of this prescription. Additionally, research is warranted to understand better the determinants of higher antimicrobial prescribing in the private healthcare sector. Highlights- MTZ is the second most prescribed antibiotic in the study area. - MTZ prescription is primarily driven by digestive symptoms. - The private healthcare sector is independently associated with higher MTZ prescription rates. - Antimicrobial prescribing is generally higher in private healthcare facilities than in public facilities.

Background: Antimicrobial resistance is the world's silent pandemic. The public knowledge, attitudes, and practices (KAP) about antibiotic usage are strongly related to the growing problem in Nepal. Methods: A cross-sectional descriptive survey was done to 263 respondents. Information on KAP regarding antibiotics, primary healthcare sources, and demography was collected through a questionnaire. To identify health literacy gaps and characteristics that contribute to improper antibiotic use, this study assessed these variables across an age group from 18 to 60 years. Descriptive statistics analysis was performed to analyze the data. Results: The majority of respondents were between the ages of 18 and 39 (85.1%), female (63.1%), and had at least a bachelor's degree (67.8%). Significant misunderstandings about antibiotics remained, even though 77.6% of respondents correctly recognized antibiotics as effective against bacteria; 44.1% incorrectly believed that antibiotics cure viral diseases, and 87.8% felt that antibiotics should be stopped right away if adverse effects develop. In practice, 52.9% acknowledged quitting antibiotics as soon as symptoms improved, despite 89.4% consulting doctors. Additionally, 43% of respondents said they have taken antibiotics without a prescription, frequently due to pharmacist recommendations (21.67%) and financial or geographical constraints. The main sources of information were doctors (11.07%) and pharmacist-doctor combinations (14.88%), yet 81.8% of respondents said they had never heard of the phrase antimicrobial resistance. Conclusion: There is a significant lack between theoretical understanding and practical application, despite the high levels of fundamental knowledge toward the prohibition of non-prescription sales. Self-medication and early withdrawal are still common inappropriate practices. It is crucial to implement focused teaching initiatives that highlight the differences between bacterial and viral diseases as well as the risks associated with leftover medicine. It is advised to use digital platforms for younger demographics and to strengthen the role of pharmacists in order to reduce AMR.

Antimicrobial resistance is an impactful One Health issue. One of its drivers is the extensive use of antibiotics in both human and animal production systems, and despite regulatory restrictions on antibiotic use in poultry farming, antimicrobial resistance remains a major challenge. Consequently, animals are at higher risk of harder-to-treat diseases and play a role as resistance reservoirs, highlighting the need for alternative antimicrobial strategies. Towards this end, antimicrobial peptides (AMPs) have emerged as promising candidates due to their broad-spectrum activity and lower propensity to induce resistance. However, the effectiveness of AMPs against poultry pathogens, and in particular multi drug-resistant strains, is largely unclear. To tackle this question, we evaluated the synthetic AMP SET-M33 against four species of clinically relevant pathogens in poultry, namely Escherichia coli, Salmonella enterica, Enterococcus faecalis and Enterococcus cecorum. Using a panel of 141 field isolates, we found that SET-M33 broadly inhibited bacterial growth at low micromolar concentrations (median MICs of 2.5 M and 5 M for Gram-negative and Gram-positive strains, respectively), including in multi drug-resistant isolates. To examine the potential impact of SET-M33 on the host, we established a new in vitro co-cultivation system using chicken intestinal organoids. We found that SET-M33 retains its antimicrobial activity in organoid-microbe co-cultures at concentrations that preserved host viability. These findings demonstrate the potential of SET-M33 as a new antimicrobial agent against pathogens in poultry.

BackgroundThe global rise of multidrug-resistant (MDR) bacteria represents a critical public health threat, and Romania ranks amongst the most affected countries in Europe. As conventional therapy increasingly fails, bacteriophage therapy has re-emerged as a promising alternative to antibiotics. Urban rivers, contaminated with resistant bacterial strains, represent an underexplored and accessible reservoir for the isolation of lytic phages with therapeutic potential. MethodsTwo bacteriophages, 17M_Ec17_D and 22C_Ec22_D, were isolated from the Dambovita River, Bucharest, Romania, using MDR E. coli as host bacteria. Phage characterization included plaque morphology, transmission electron microscopy, and host range assessment by spot assay against 30 MDR E. coli isolates. Whole genome sequencing was performed on Illumina MiSeq and Oxford Nanopore Technologies MinION platforms, followed by bioinformatic analysis including taxonomic classification, lifestyle prediction, and functional annotation. ResultsBoth phages formed clear plaques and were classified as Kayfunavirus (17M_Ec17_D, Podoviridae-like) and Kagunavirus (22C_Ec22_D, Siphoviridae-like) with nucleotide similarities of 89.2% and 71.4% to their closest relatives, respectively, suggesting both are candidates for novel species. Host range analysis revealed lytic activity against 13% and 10% of tested MDR isolates, with complementary infection profiles. Genomic analysis confirmed a strictly lytic lifestyle for both phages, supported by the presence of holin and spanin genes and the absence of lysogenic modules, antibiotic resistance genes, and virulence factors. ConclusionsTo the best of our knowledge, this is the first study conducted in Romania to isolate and genomically characterize lytic bacteriophages targeting MDR E. coli. The characterized phages represent safe therapeutic candidates whose complementary host ranges suggest potential application as part of phage cocktail to broaden antimicrobial coverage against MDR infections.

ObjectiveThe aim of the study was to investigate knowledge, attitudes and practices (KAP) of Italian general practitioners regarding the use of food supplements. Subject and MethodsA 62-question survey, adapted from a tool used among pharmacists, was sent to Italian general practitioners. The survey contains two sections: A) KAP questions (28 true/false, 34 on a 5-point Likert scale) and B) socio-demographic questions. Results233 questionnaires were collected from March to July 2024. 44.6% of responders were male, 54.9% female. The majority (68.2%) came from an urban environment and 53.65% worked with other colleagues. Most of the general practitioners (69.1%) showed an adequate knowledge of the subject (> 60% of correct answers). The overall reliability of the test was rated as acceptable (alfa>0.7). 98.7% of general practitioners agreed that they have an important role in prescribing dietary supplements, and 98.3% are involved in lifestyles counselling, but only 66.52% felt that they had adequate training on this subject. ConclusionGeneral practitioners recognize their pivotal role in supplement prescription, but, even if their knowledge scores were adequate, they feel a need of more specific education on the topic.

Urinary tract infections (UTIs) are the most prevalent bacterial infections globally, and their management increasingly challenged by antimicrobial resistance (AMR). Probiotics offer a promising approach to mitigate AMR by competitively excluding uropathogens and enhancing host immunity by producing immune modulators. Despite being potential, key gaps persist between the discovery of uroprotective probiotic strains and optimization of formulations for urinary tract delivery. Here, we analyzed the urinary microbiome of UTI patients and healthy individuals to identify potential probiotic candidates for the prevention and management of UTIs. Publicly available 16S rRNA amplicon sequencing data of the urinary tract were processed using a standardized pipeline for sequence quality assessment, taxonomic assignment, and microbial function prediction. Comparative analysis showed a significant shift in microbial composition between UTI patients and healthy controls. The dominated phyla identified included Acidobacteriota, Actinobacteriota, Bacteroidota, Campylobacterota, Cyanobacteria, Firmicutes, Fusobacteriota, Patescibacteria, Proteobacteria, and Synergistota. Overall differential abundance analysis revealed Escherichia coli as the predominant UTI-associated species, while Lactobacillus crispatus was enriched in healthy samples. Additionally, predictive functional analysis indicated that metabolic pathways associated with beneficial microbes were enriched in the healthy group. Overall, the study highlights the association of distinct urinary microbiome signatures with infection status, which supports L. crispatus as the most promising probiotic for UTI prevention and control.

Biofilms pose a significant challenge to antimicrobial therapy. Bacteria in biofilms differ from planktonic counterpart in their altered metabolism, collective behavior, protective role of extracellular matrix and diversified microbial subpopulations. These attributions significantly influence bioavailability and activity of antibiotics. The presence of bacterial aggregates during acute infections expands the problem to many other conditions previously not discussed in the biofilm context. Klebsiella pneumoniae is a leading cause of life-threatening hospital-acquired infections and is included in the WHO Bacterial Priority Pathogens List due to increasing antimicrobial resistance. The combination of antimicrobial resistance and the ability to form biofilms severely limits the efficacy of antibiotic treatments. In this study, we investigated the in vitro susceptibility of mature biofilms to 13 antimicrobials of K. pneumoniae clinical isolates from a single hospital. The resistance profiles of the local clinical isolates were consistent with the global epidemiology of K. pneumoniae. Minimal biofilm eradication concentrations (MBEC) for mature biofilms were defined with two assays (biomass and metabolic activity measurements) and brought into relation with susceptibility breakpoints and plasma (Cmax). Colistin sulfate, tigecycline, cephalosporins and combination of imipenem with cilastatin were the most potent biomass eradicators, while suppression of metabolic activity was barely reachable. Moreover, we observed a notable increase in metabolic activity upon exposure to sub-MBEC concentrations of antibiotics. Finally, our data broach a subject of antibiotic prioritization with respect to biofilm tolerance. IMPORTANCEThis study addresses the critical gap between standard antibiotic susceptibility testing and the tolerance of biofilm and microbial aggregates during infections caused by K. pneumoniae. By systematically evaluating mature biofilms from a significant number of clinical isolates, we demonstrate that colistin and tigecycline show potent activity against both biofilm biomass and metabolic activity, whereas cephalosporins primarily reduce biomass without effectively suppressing bacterial metabolism, and other drugs have only weak effects on biofilms at clinically achievable concentrations. Furthermore, the alarming observation that sub-inhibitory biofilm eradication concentration (sub-MBEC) of antibiotic can paradoxically increase the metabolic activity of biofilms highlights a potential risk factor for therapy failure and resistance development. Our findings contribute to the necessary evidence base for prioritizing existing antibiotics in the limited armamentarium against biofilm-forming K. pneumoniae.

BackgroundTransfer of Streptococcus agalactiae, or Group B Streptococcus (GBS) from parent to newborn during delivery can produce life-threatening infections in neonates. Probiotics could potentially prevent GBS colonization in pregnant individuals. We conducted a systematic review and meta-analysis to evaluate the effectiveness of probiotic administration in treating Group B Streptococcus colonization. MethodsMEDLINE, ClinicalTrials.gov, PROSPERO, and the Cochrane, Wild Card, Central Register of Controlled Trials were searched from the July 2015 of each database until July 2025 that completed a randomized controlled trial which compared Probiotic versus control. We utilized the Cochrane Risk of Bias 2.0 (RoB 2) tool to assess bias in the systematic review. Results14 randomized controlled clinical trials met our inclusion criteria. The trials used oral probiotic administration compared to either a placebo or a control group. A meta-analysis showed that probiotic administration produced a statistically significant decrease in the rate of GBS colonization in pregnant individuals. The individual studies ranged from four showing great effectiveness, while the other 10 studies showed a range of effectiveness, from partially effective to no effectiveness in preventing GBS colonization. ConclusionOverall, probiotics were effective in lowering infection rates of GBS, but individual studies showed great variability. Probiotics show promise in decreasing GBS colonization in pregnant people, but more studies need to be performed in order to use them effectively and decrease antibiotic usage.

The gut microbiome plays a central role in host metabolism, immune function, and overall health, with disruptions in microbial composition (dysbiosis) being associated with a range of metabolic, inflammatory, and infectious conditions [1,2]. Consequently, strategies aiming to modulate the microbiome require selective activity that preserves beneficial commensals while limiting pathogenic organisms [3]. In this context, ThymoQuin(R)--a cold-pressed, standardized black cumin (Nigella sativa) seed oil developed by TriNutra Ltd. and defined by [&ge;]3% thymoquinone (TQ), controlled p-cymene levels, and low free fatty acids ([&le;]1.25%)--was evaluated for its microbiome-relevant activity. In vitro minimum bactericidal concentration (MBC) assays across three independent batches demonstrated a biphasic, dose-dependent response. At intermediate concentrations (0.25-0.5%), Streptococcus thermophilus was strongly stimulated (up to 53-fold) and Lactiplantibacillus plantarum fully preserved, while Klebsiella pneumoniae was effectively reduced (>94%). Akkermansia muciniphila exhibited stable viability at concentrations below 1%, with reductions only observed at 1%. This is notable given its role as a mucin-degrading commensal that has been linked to metabolic health, but whose abundance may vary across physiological and disease contexts [4,5]. At concentrations [&ge;]1%, selective effects diminished, resulting in broader antimicrobial activity and reduced specificity. These findings indicate a defined concentration range in which selective microbiome modulation is maintained, whereas higher thymoquinone levels may increase the risk of non-selective detrimental effect on microbes.