Search Results (210)

Staphylococcus aureus is a leading cause of bacterial keratitis and antimicrobial resistance-associated death globally. This study aimed to evaluate the efficacy of CaD23, a human-derived hybrid antimicrobial peptide (AMP), in combination with antibiotics in treating S. aureus infections. The efficacy of CaD23 and six medically important antibiotics (amikacin, cefuroxime, chloramphenicol, fosfomycin, vancomycin and levofloxacin) was examined against six strains of methicillin-sensitive and methicillin-resistant S. aureus using a minimum inhibitory concentration (MIC) assay. CaD23–antibiotic interactions were evaluated using checkerboard and time–kill kinetics assays. 3,3′-dipropylthiadicarbocyanine iodide (DiSC_3,5) cytoplasmic membrane depolarisation assay was performed to examine the mechanism of action. Overall, CaD23 exhibited good efficacy against all MSSA and MRSA (MIC = 16–32 μg/mL [6.7–13.3 μM]). Of 20 peptide–antibiotic–organism combinations, 19 (95%) combinations demonstrated positive interactions, with six (31.6%) and 13 (68.4%) exhibiting synergistic (FICI = 0.293–0.412) and additive effects (FICI = 0.521–0.890), respectively. CaD23 was able to achieve complete bacterial eradication significantly faster than cefuroxime and levofloxacin (15 min vs. 8–24 h). When used at a sub-MIC concentration, CaD23 could accelerate the killing of S. aureus of cefuroxime from 8–24 h to within 1 h and enhance the activity of levofloxacin by 90%. CaD23 was shown to rapidly depolarise the inner membrane of S. aureus within seconds of the treatment. In conclusion, CaD23–antibiotic combination therapy serves as a useful strategy for tackling drug-resistant ocular and systemic S. aureus infections. Full article

Background/Objectives: The objective of this study was to evaluate macular perfusion changes after intracameral injection (ICI) of cefuroxime at the end of phacoemulsification. Methods: Patients who underwent routine phacoemulsification were enrolled. Subjects in the case group had ICI 1 mg/0.1 mL cefuroxime at the end of surgery. Using optical coherence tomography angiography (OCT-A), macular perfusions were assessed at T0 (before surgery), T1, T10, T30, and T90 (days after surgery). Perfusion parameters were calculated in the superficial capillary plexus (SCP) and the deep capillary plexus (DCP). Independent t-tests were used to compare the changes from baseline in each parameter between groups. Results: A total of 33 eyes in the case group and 27 eyes in the control group were enrolled. After surgery, the case group showed a less pronounced reduction in the foveal avascular zone (FAZ) in the DCP at T10 (−0.06 ± 0.23 vs. −0.18 ± 0.18 mm², p = 0.041) and T30 (−0.04 ± 0.20 vs. −0.16 ± 0.24 mm², p = 0.050). At T90, there was no statistically significant difference in the FAZ change in the DCP between the groups. The postoperative changes in the vessel density, skeleton density, and acircularity index of the FAZ in the SCP and DCP, central retinal thickness, and best-corrected visual acuity were similar between the groups in all 3 months. Conclusions: Our findings indicate that intraoperative ICI low-dose cefuroxime is associated with a temporary deceleration in FAZ reduction in the DCP during the first postoperative month. From a personalized medicine perspective, these layer-specific microanatomic variations suggest that, while prophylactic cefuroxime is globally safe—demonstrating no evidence of inducing capillary dropout, aggravating macular thickening, or compromising visual outcomes within this cohort—preoperative and postoperative OCT-A monitoring can serve as an individualized screening framework to track subclinical perfusion dynamics, especially in patients with compromised retinal baselines. Full article

Background: Pulmonary fibrosis (PF) is a major global health issue associated with substantial morbidity across all age groups. One of the important etiological factors contributing to PF is drug-induced lung injury, which can result from both direct and indirect damage to the pulmonary parenchyma caused by various pharmacological agents, including chemotherapeutics, antirheumatic drugs, cardiovascular medications, and certain antimicrobial agents. The aim of our study was to assess the structure of antibacterials involved in drug-induced PF (DIPF) and analyze signals of DIPF, calculating the reporting odds ratio (ROR) and proportional reporting ratio (PRR) using spontaneous reports (SRs) extracted from the Russian National Pharmacovigilance database. Methods: A retrospective, descriptive pharmacoepidemiological analysis of SRs from the AIS database for the period 1 April 2019–31 March 2025 was conducted. Results: A total of 130 SRs with data on DIPF associated with antibacterial agents were identified, with patients’ mean age of 59.1 ± 14.46 years. Death was reported in 65 SRs (50%) with a mean age of 53.0 ± 13.66 years. Next, antibacterials were identified as leaders: sulfamethoxazole (used alone or in combination with trimethoprim, 20.7% (n = 50)), azithromycin (18.2%, n = 44), levofloxacin (12.4%, n = 30), doxycycline (11.6%, n = 28), and cefuroxime (10.7%, n = 26). Disproportionality analysis performed with PRR and ROR calculation revealed the strongest association with DIPF for cefuroxime (PRR = 15.11, 95% confidence interval, CI: 10.25–22.27; ROR = 15.31, 95% confidence interval, CI: 10.33–22.68). Conclusions: Cefuroxime was revealed as a drug with an unexpected but robust safety signal for DIPF, warranting heightened clinical awareness and further investigation. The observed associations between antibacterial agents and DIPF should be interpreted with caution, as they may reflect protopathic bias (antibiotics prescribed for early symptoms of unrecognized pulmonary fibrosis) or context-dependent biological effects rather than true pro-fibrotic drug properties. Our findings do not establish causality but rather generate safety signals that warrant validation through prospective studies with detailed clinical phenotyping and mechanistic investigations using human cell lines. Full article

Background/Objectives: Early-stage antibacterial discovery requires balancing activity with broader developability-related properties. This study developed a Fivefold Maximum Drug-Likeness strategy (5F-MDL) as a multidimensional, developability-aware framework for prioritizing antibacterial candidates against Escherichia coli (E. coli). Methods: An ensemble of endpoint-specific deep learning models was used to construct a 33-dimensional predicted property spectrum. Approximately 16 million commercially available molecules were screened by comparing their normalized property profiles with those of clinically approved cephalosporin reference drugs. Fifteen top-ranked candidates were selected for experimental evaluation. Antibacterial activity was assessed by disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays. Molecular docking, molecular dynamics simulations, MM-PBSA analysis, and a Bocillin-FL competition labeling assay were used as target-related supportive analyses. Results: Among the 15 prioritized candidates, three compounds showed measurable antibacterial activity against E. coli ATCC 25922. M2 showed the most favorable in vitro profile among the active candidates, with an MIC of 25.6 µg/mL and an MBC of 51.2 µg/mL, although its potency remained weaker than that of cefuroxime. Docking, molecular dynamics, and MM-PBSA analyses suggested that M2 could maintain a relatively stable noncovalent interaction pattern within the modeled PBP2 pocket, and the Bocillin-FL assay showed that M2 reduced fluorescent probe labeling of PBP2 in vitro. Conclusions: These findings provide preliminary proof-of-concept support for 5F-MDL as a multidimensional prioritization strategy for early-stage antibacterial candidate selection. M2 should be regarded as a preliminary antibacterial hit for further optimization rather than as a validated lead compound. Broader applicability, comparative advantage, and mechanistic relevance require further validation using larger candidate sets, resistant clinical isolates, systematic benchmarking, and direct target-validation experiments. Full article

Background: Kounis syndrome is an allergic acute coronary syndrome precipitated by coronary vasospasm, plaque destabilization, stent thrombosis, or bypass occlusion. Cardiac surgery represents a uniquely high-risk setting due to cardiopulmonary bypass–associated inflammation and exposure to multiple pharmaceutical agents. Importantly, Kounis syndrome remains underrecognized in this context, as classical signs of anaphylaxis may be masked under general anesthesia and cardiopulmonary bypass, while ischemic manifestations may be misattributed to other perioperative conditions. Methods: A narrative review of PubMed-indexed literature was conducted to synthesize current evidence on the pathophysiology, perioperative triggers, clinical presentation, diagnostic strategies, and management of Kounis syndrome in cardiac surgery, with emphasis on intraoperative recognition and surgical decision-making. Published cases were retrieved involving perioperative cardiac surgery patients with a definite diagnosis of Kounis syndrome. Additionally, cases presenting with severe perioperative anaphylaxis and life-threatening cardiovascular involvement (grade III with cardiovascular collapse and grade IV with cardiac arrest) were included as possible Kounis syndrome, reflecting real-world diagnostic uncertainty in the intraoperative setting. Results: The literature review identified five cases of definite Kounis syndrome and ten cases of possible Kounis syndrome, including three cases with cardiovascular collapse and seven cases with cardiac arrest. Recurrent episodes were reported in several patients, particularly due to re-exposure to the triggering agent. In the context of cardiac surgery, Kounis syndrome is most frequently triggered by chlorhexidine, protamine, antibiotic prophylaxis, and anesthetic agents. The clinical presentation is often subtle during cardiopulmonary bypass. Vasoplegia, pulmonary hypertension, ventricular dysfunction, new regional wall-motion abnormalities, and hyperdynamic ventricles on transesophageal echocardiography commonly precede overt electrocardiographic changes. Diagnosis is primarily clinical and relies on intraoperative ultrasound, hemodynamic monitoring, serum tryptase, serum troponin, and, when indicated, coronary angiography. A dual-pathway approach addressing both anaphylaxis and myocardial ischemia is essential; however, one component may predominate, particularly in perioperative patients with limited clinical information, potentially leading to misdiagnosis. A multidisciplinary approach is therefore required for rapid diagnosis and individualized management. In refractory cases, cardiopulmonary bypass or ventricular assist devices may provide lifesaving support. Conclusions: Kounis syndrome remains underrecognized in cardiac surgery but carries significant morbidity. Increased clinical awareness, multidisciplinary collaboration, structured diagnostic approaches, and preventive strategies are essential to improve outcomes and reduce the risk of recurrence during future procedures. Full article

Introduction: Periprosthetic joint infections (PJI) are among the most serious and costly complications in orthopedic surgery, significantly affecting patient prognosis and healthcare systems. Despite rigorous aseptic measures, intraoperative contamination of sterile fields, instruments, and air remains a persistent source of potential infection. This study investigates the relationship between the microbial contamination of sterile fields during arthroplasty and postoperative inflammatory markers, with the objective of determining whether the contamination of sterile fields correlates with the presence of periprosthetic joint infection (PJI). Material and Methods: This prospective observational study included 33 patients undergoing total hip or knee arthroplasty in a university-affiliated orthopedic center. Intraoperative samples were collected from sterile fields and equipment to detect microbial contamination, while postoperative monitoring involved the C-reactive protein (CRP); erythrocyte sedimentation rate (ESR); leukocyte count; temperature; and wound assessment on days 1, 3 and 7. All patients received 48 h of prophylactic cefuroxime. Statistical analysis was conducted using the International Business Machines (IBM) Statistical Product and Service Solutions (SPSS) software for Windows, version 30.0 (IBM Corporation, Armonk, New York, United States of America) with significance set at p ≤ 0.05. Results: Postoperative inflammatory markers showed distinct patterns depending on the isolated microorganism, with Proteus vulgaris and Staphylococcus hominis ssp. consistently associated with higher CRP and leukocyte values, indicating a more intense systemic response. Staphylococcus epidermidis was the most frequently isolated species but showed moderate inflammatory profiles, suggesting its potential role in subclinical colonization. A strong correlation between CRP on day 3 and leukocyte count (r = 0.81) confirms their combined utility in the early detection of infectious complications, while ESR appeared less dynamic and more complementary in nature. Discussion: This study highlights the significant role of intraoperative contamination and microbial virulence in shaping the postoperative inflammatory response after arthroplasty. Elevated CRP and leukocyte levels, particularly on day 3, were closely associated with pathogens known for biofilm formation and chronic infections. Despite prophylactic antibiotic use, confirmed infections still occurred, suggesting the need to reassess current protocols and enhance intraoperative contamination control. Conclusions: Pathogen presence in sterile fields during arthroplasty increases the risk of periprosthetic joint infections, often without early clinical symptoms. CRP on day 3 and leukocyte count were the most reliable early indicators of persistent inflammation. Full article

Background: Antimicrobial resistance coupled with the lack of new antibiotics calls for the responsible use of antibiotics, including old antimicrobials. Aminoglycosides are effective against bacteria in acute appendicitis, a common intra-abdominal infection. Their use has been discouraged recently, but their place in therapy is based on studies performed in the era of lower resistance rates, and with multiple dosing regimens. Methods: In a prospective randomized open-label study, we compared the efficacy and safety of gentamicin in one daily dose and metronidazole (GTM+MZ) to ertapenem (ETP) and to cefuroxime with metronidazole (CXM+MZ) in adult patients surgically treated for acute appendicitis. Efficacy was assessed via the duration of antibiotic treatment and hospital stay, c-reactive protein (CRP) dynamics, and post-operative complications. Nephrotoxicity was assessed with urine biomarkers. Statistical analysis comprised mixed-model analysis of variance (ANOVA) with the missing-data-imputation method and linear mixed model (LMM). Results: One hundred-and-sixty-six patients were included in this study. There were no significant differences among the three groups in the durations of treatment and lengths of stay (p = 0.093, p = 0.222). CRP level was the lowest (p = 0.003) in the ETP group. There were five complications during hospitalization, with two of them classified as infectious. Both occurred in the GTM+MZ group; however, the difference was not statistically significant (p = 0.330). No difference was found in complications in the month following the operation (p = 0.763). Biomarkers indicating kidney injury showed the same trend in all three groups. Conclusions: Our results suggest the use of once-daily dose of gentamicin following an appendectomy for acute appendicitis. Gentamicin may be used to decrease selective pressure of other antimicrobials. Full article

Background and Objectives: Appropriate antimicrobial dosing according to kidney function is essential to ensure therapeutic efficacy while minimizing toxicity and antimicrobial resistance. Despite established dosing guidelines and electronic prescribing systems, errors in renal dose adjustment of antimicrobials, particularly in the setting of acute kidney injury, remain common among hospitalized patients. Materials and Methods: A point-prevalence study was conducted on 31 October 2024 at a tertiary-care hospital in Greece to evaluate the appropriateness of antimicrobial dosing in relation to renal function. Patient characteristics, renal parameters, and antimicrobial prescriptions were extracted from electronic medical records. Glomerular filtration rate (GFR) was estimated using the MDRD formula. Comparative analyses were performed between correctly and incorrectly dosed cases, and between overdosing and underdosing episodes. Results: A total of 235 hospitalized patients were evaluated (mean age 64.8 ± 18.6 years; 43.4% female). Overall, 15.7% (37/235) received at least one antimicrobial dose inappropriate for their renal function. Among 37 patients where dosing errors were identified, overdosing was noted in 23 (62.2%), underdosing in 16 (43.2%), adding up to 39 prescriptions, while in 2 patients (5.4%), both mistakes were noted in different prescribed antimicrobials. Drug-specific error rates varied considerably: ceftazidime and cefuroxime showed the highest rates of inappropriate dosing (40% each), followed by colistin (33.3%) and acyclovir (33.3%). Piperacillin/tazobactam, the most frequently prescribed agent (n = 50), had a 14% error rate, mainly due to underdosing (10%). Patients with dosing errors were significantly older (71.5 vs. 64.1 years, p = 0.0220) and had worse renal function, including higher serum creatinine (1.68 vs. 1.19 mg/dL, p = 0.0174), lower GFR (58.5 vs. 75.9 mL/min/1.73 m², p = 0.0009), and more frequent dialysis (13.5% vs. 4.3%, p = 0.0422). They also received a higher median number of antimicrobials (2 vs. 1, p = 0.0185). Conclusions: Inappropriate antimicrobial dosing based on kidney function remains common in hospitalized patients, particularly among older individuals and those with impaired renal function or polypharmacy. Targeted antimicrobial stewardship strategies focusing on renal dose adjustment and agents that are more frequently dosed inappropriately, such as colistin, acyclovir, cefuroxime, and ceftazidime, as well as agents that are frequently prescribed despite a relatively lower rate of inappropriate dose, such as piperacillin/tazobactam, are needed to enhance prescribing safety and optimize therapeutic outcomes. Full article

Background/Objectives: To prevent surgical site infections, it is important to consider the concentration of the administered antibiotic in the target compartment. We measured the concentrations of cefuroxime and metronidazole in peritoneal fluid with the microdialysis technique in patients undergoing surgery for secondary peritonitis (7 patients) and for inflammatory bowel disease (11 patients). Methods: All patients received 1.5 g of cefuroxime and 0.5 g of metronidazole every 8 h during the postoperative period for at least 72 h. Microdialysates covering 8-h intervals were collected, and the concentration of cefuroxime and metronidazole was measured using liquid chromatography–mass spectrometry. Results: For metronidazole, a concentration of ≥4 μg/mL was reached in all but one sample, corresponding to the minimal inhibitory concentration (MIC) for most anaerobic bacteria strains. For cefuroxime, a value of ≥4 μg/mL was reached in 88% and 93% of the samples in the peritonitis group and the IBD group, respectively, corresponding to the MIC values for most Gram-negative bacteria, and a value of ≥16 μg/mL, corresponding to the MIC value for more resistant bacteria, was reached in only 40% and 23% of the samples, respectively. Conclusions: Our results show that the peritoneal microdialysis method is feasible for studying the diffusion of antibiotics into the peritoneal cavity. Measuring the accumulative concentration of antibiotics in the peritoneal fluid corresponding to the drug administration interval may provide important information to consider alongside traditional pharmacodynamic parameters and may be relevant to achieving an optimal therapeutic effect. Full article

Background/Objectives: In the broad and current context of antimicrobial resistance, antibiotic management and therapeutic surveillance are essential in hospitals. The present study (five-year retrospective, 2020–2024) aimed to analyze antibiotic consumption in relation to pathogens identified in a multidisciplinary hospital. Results: In terms of antibiotic consumption (overall 2020–2024), although initially Watch antibiotics were predominantly used, a decrease was observed in favor of Access class antibiotics (sharply increase from 2022 to 2023 and maximum in 2024). For Reserve antibiotics, only slight annual fluctuations were observed, but there was an important reduction in colistin consumption. The most used were cephalosporins (cefazolin, cefuroxime and ceftriaxone), carbapenems (meropenem and ertapenem), vancomycin and linezolid. Regarding pathogens, the most notable were: Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Enterococcus spp., Pseudomonas aeruginosa. Among the ESKAPE bacteria, Acinetobacter baumannii was the least frequent in our samples. ESKAPE bacteria predominantly colonized specimens from the respiratory tract, digestive tract, skin and soft tissue. Resistant strains were observed, mainly Methicillin-resistant Staphylococcus aureus (MRSA) and Extended-Spectrum Beta-Lactamase (ESBL) Klebsiella spp., but no alarming increases in number were recorded in the analyzed period. Methods: The analysis was carried out using tools recommended by the World Health Organisation (Access Watch Reserve antibiotics classification (AWaRe); Bacterial Priority Pathogen List (BBPL); Defined Daily Dose (DDD)), Average Annual Percent Change (AAPC) calculation and ESKAPE classification (bacteria group: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.). Conclusions: Relatively stable trends in bacterial isolates and resistant strains over five years (2020–2024) are consistent with effective antimicrobial stewardship practices. Full article

Background/objectives: A rise in infections associated with carbapenem-resistant Providencia species (CRPS) has been observed worldwide. This study presents a genomic analysis of CRPS isolates from four hospitals in Croatia and the outpatient setting, in order to determine the extent of the spread of CRPS in Croatia. In the present study, we applied a combination of phenotypic characterization and molecular analysis of resistance traits to determine the mechanisms and the routes of spread of CRPS. Material and methods: The antibiotic susceptibility testing was performed using disk-diffusion and broth dilution methods. The nature of extended-spectrum β-lactamases (ESBLs), carbapenemases, and fluoroquinolone resistance determinants was investigated by polymerase chain reaction (PCR). In order to obtain an insight into the whole resistome, selected isolates were subjected to the Interarray Genotyping Kit CarbaResist and whole genome sequencing (WGS). Results: In total, 30 isolates were collected from four centers, located in different geographic regions of Croatia. There was uniform resistance to piperacillin-tazobactam, cefuroxime, expanded-spectrum cephalosporins (ESCs), imipenem, ertapenem, meropenem, and ciprofloxacin. Immunochromatographic testing and PCR revealed OXA-48 and NDM carbapenemase in 15 isolates, respectively. Phenotypic tests for ESBLs were positive in all OXA-48 and one NDM-positive organism (16 isolates). The isolates were categorized as extensively drug-resistant (XDR). OXA-48-producing isolates were susceptible only to ceftazidime-avibactam, whereas NDM producers were susceptible to cefiderocol and, in the majority of cases, also to amikacin. WGS identified a plethora of genes encoding resistance to aminoglycosides, such as aadA1 and aadA2, (aph(3″)-Ib and aph(6)-Id, sulfonamides sul1 and sul2, trimethoprim dfrA1, dfrA10, and dfrA12, tetracyclines tet(A) and tet(B), and chloramphenicol catA3 and catA5. Conclusions: Providencia spp., in spite of being a rare pathogen, should be included in the surveillance studies across the medical centers in Croatia. Full article

Background: Bovine mastitis (BM) remains an economically significant disease in the global dairy industry. Multidrug resistance (MDR) in Klebsiella pneumoniae and Klebsiella grimontii has increased in recent years, representing an area of concern related to BM. Methods: Bovine mastitis 1-DH1 and 2-DH2 isolates (n = 2) were investigated. Antimicrobial susceptibility testing was performed using the Neg-Urine-Combo98 panel. Antimicrobial resistance genes (ARGs), virulence factor (VF) genes and plasmid replicons were identified by whole-genome sequencing (WGS). Phylogenomic analyses were performed for a visual comparison of the genomes. Results: Phenotypically, isolates 1-DH1 and 2-DH2 were identified as K. pneumoniae-1DH1 and Klebsiella oxytoca, respectively; the latter was subsequently confirmed as K. grimontii-2DH2 by WGS. K. pneumoniae-1DH1 (20.0%, 5/25) exhibited phenotypic resistance to amoxicillin–clavulanic acid, ampicillin (AM), cefuroxime, colistin (Cl), and nitrofurantoin (Fd), whereas K. grimontii-2DH2 (8.0%, 2/25) was resistant to AM and nalidixic acid (NA). In total, 31 and 32 ARGs and 10 and 15 VF genes were identified in K. pneumoniae-1DH1 and K. grimontii-2DH2, respectively. Two plasmid replicons were detected in K. pneumoniae-1DH1 (one harboring the blaCTX-M ARG) compared to one in K. grimontii-2DH2 (encoding both the blaCTX-M ARG and the astA VF gene) isolates, respectively. Phylogenomic analysis showed that K. pneumoniae-1DH1 clustered most closely with human-derived K. pneumoniae isolates, whereas K. grimontii-2DH2 grouped with environmental K. grimontii isolates. Conclusions: Novel phenotypic resistance profiles were observed in the BM-associated K. pneumoniae-1DH1 (MDR, Cl and Fd) and K. grimontii-2DH2 (AM and NA) isolates. Notably, K. grimontii-2DH2 harbored a plasmid replicon carrying both the blaCTX-M ARG and the astA VF gene. Full article

Clinical data on antimicrobial profiles are useful for dairy udder health treatment programmes and represents a component of antimicrobial stewardship. The study aimed to determine the bacterial aetiology of clinical mastitis in dairy herds in Western Australia and to evaluate their antibiotic resistance profiles. This retrospective study utilised clinical antimicrobial profile data from two referral diagnostic centres within the region of Western Australia. A total of 545 mastitic samples were submitted for antimicrobial culture and testing over a period of 10 years (2008–2018). Of these, 406 showed bacterial growth and 139 no bacterial growth was observed. The most common isolates were Streptococcus uberis (25.3%), Staphylococcus aureus (17.2%), and Escherichia coli (9.4%). No growth was identified in 25.5% of the mastitis milk samples. The antimicrobial profiles revealed high susceptibilities towards cefuroxime (95.7%), clavulox (89.4%), and oxytetracycline (89%), whilst showing high resistance towards novobiovin (70%). From this study, it is concluded that there was a decline in the resistance trends towards the isolates of both S. uberis and S. aureus over the 10-year period and contagious mastitis had a higher occurrence. There is a need to consider surveillance programmes that determine the patterns of on-farm antimicrobial usage and further characterise the pathogens based on the presence of resistance antimicrobial genes. Data on antimicrobial surveillance represent an important component of antimicrobial stewardship. Full article

Listeria monocytogenes is a high-risk pathogenic bacterium associated with ready-to-eat foods and poses a potential threat to consumer health. This study aimed to investigate the prevalence, characterization and genetic diversity of L. monocytogenes in ready-to-eat raw salmon and trout products obtained from physical stores and online stores in China. Out of 150 samples analyzed, 23 (15.3%) were positive for L. monocytogenes. Among these positive samples, three (12%) were from Japanese restaurants, four (16%) from farmers markets, one (2.9%) from large supermarkets and fifteen (30%) from e-commerce platforms, and only one sample showed a contamination level exceeding 100 most probable number (MPN)/g. The isolates from positive samples demonstrated a concrete public health risk through several findings: twenty-three L. monocytogenes exhibited varying degrees of cytotoxicity, ranging from 7.6% to 71.8%. Compared with the reference strain ATCC 19115, five of these isolates were highly cytotoxic, a result that was validated by mouse survival rate experiment, which also confirmed their high virulence at tested dose. All isolates were resistant to cefuroxime sodium, ceftriaxone, cefepime and nalidixic acid, and 13% showed resistance to sulphamethoxazole-trimethoprim. Three serogroups were identified, with serogroup Ⅰ.1 (1/2a, 3a) being the most prevalent (65.2%). These isolates were grouped into eight sequence types, with ST8 (34.8%) and ST87 (30.4%) dominating. All isolates carried virulence genes associated with LIPI-1 andmultiple internalin genes (inlA, inlB, inlJ and inlK), confirming their potential pathogenicity. Additionally, the isolates harbored antimicrobial resistance genes lin and FosX. The five highly virulent isolates exhibited the highest genetic similarity to J2-031 (GCA_000438645.1) and C1-387 (GCA_000438605.1). The results provided valuable information for Chinese regulatory authorities to strengthen the risk monitoring of L. monocytogenes in ready-to-eat raw salmon and trout products. Full article

Growing environmental concern over pharmaceutical contaminants in water, combined with the limited effectiveness of conventional treatment methods in removing persistent antibiotics, creates a need for advanced remediation technologies. This study investigates the degradation of the cephalosporin antibiotic cefuroxime axetil using an electrochemical advanced oxidation process with a boron-doped diamond (BDD) anode. Experiments were conducted under varying pH levels and in natural water matrices, specifically river and lake water, to evaluate the process efficiency under realistic conditions. Significant differences were observed between matrices, with the best result obtained in river water, enabling complete degradation of cefuroxime axetil within 30 min. To clarify the factors influencing process efficiency, additional experiments examined the effects of dissolved organic matter (DOM) and chlorides. Cefuroxime axetil proved highly susceptible to electrooxidation, generally following pseudo-first-order kinetics, and chloride significantly accelerated its degradation. Using high-resolution mass spectrometry, ten transformation products were identified, including six not previously reported in the literature, representing a key novelty of this work. Their potential aquatic toxicity was subsequently evaluated in silico using fish and algae models. Finally, energy consumption analysis was conducted to evaluate the impact of various factors on the process’s economic efficiency. Full article