Search PubMedSearch

SEARCH · Search PubMed

Results for “Antimicrobial Cationic Peptides”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

128 records · Page 4Linked to original sources

O'nyong-nyong virus adaptive mutations in non-structural protein 1 and 3 enhance RNA replication and overcome FHL1 requirement.

Arthritogenic alphaviruses, like o'nyong-nyong virus (ONNV), cause debilitating musculoskeletal diseases and are geographically expanding. To predict their emergence, we seek to better understand evolutionary mechanisms that enable changes in virus tropism. Here, we identify adaptive mutations in the ONNV non-structural proteins (nsPs) that arose during cellular serial passaging and enabled ONNV to infect non-permissive Lunet cells. Using shotgun proteomics, we show that this human hepatoma cell line lacks the four-and-a-half-LIM domain protein 1 (FHL1), an essential host factor in ONNV RNA replication. Individual single nucleotide mutations in the nsP1 ring-aperture membrane-binding and oligomerization domain, the nsP3 macrodomain, and the nsP3 opal stop codon overcome FHL1 deficiency in Lunet cells by enhanced RNA replication. These findings demonstrate how subtle genomic changes in nsPs can profoundly influence alphavirus replication and tropism.

LIM Domain Proteins

Sex- and development-specific transcriptomic profiling of venom and silk genes in the wolf spider Pardosa astrigera provides insights into ecological adaptation and predatory strategies.

Spider venom and silk glands are two major secretory systems that contribute to prey capture, defense, and reproduction, but their sex- and development-specific molecular regulation in wandering wolf spiders remains poorly understood. Here, the transcriptome of Pardosa astrigera, an important agricultural natural enemy in China, revealed significant sex- and development-associated molecular differentiation among adult females, adult males, and spiderlings. A total of 100,025 unigenes were obtained, of which 23,852 were functionally annotated, providing a comprehensive transcriptomic resource for this species. Differential expression patterns showed marked variation among groups, with 531, 1792, and 832 DEGs detected in PAF vs PAS, PAM vs PAS, and PAF vs PAM, respectively. These genes were mainly associated with metabolic, oxidation-reduction, cuticle development, MAPK signaling, and lysosome pathways. Fifteen co-expression modules revealed distinct expression patterns. The turquoise, pink, yellow, and red modules were development-related, whereas the blue module was male-biased. Venom- and spidroin-related genes were distributed across multiple modules, suggesting coordinated regulation. Overall, 42 venom peptides, 21 venom proteins, and 11 spidroins were identified. Representative genes showed strongly biased expression, including spiderling-biased U3_Pp1a and U5_Pp1e, female-biased U4_Pp1a, and male-biased SMase D_108750 and PaTuSp_108466. These findings reveal sex- and development-biased expression patterns of venom- and silk-related candidate genes in P. astrigera and may provide molecular insights into ecological adaptation and predatory strategies in wandering wolf spiders.

Animals

Induced degradation of Ufd1 reveals regulation of cohesin by the VCP/p97Ufd1-Npl4 complex.

The AAA ATPase VCP/p97 has emerged as a critical regulator of ubiquitin and chromatin-associated processes but progress in understanding has been hampered by the complexity of p97 functions and the various p97 cofactors involved. Here, we combined ubiquitin profiling with acutely induced degradation of the Ufd1 subunit of the p97 ubiquitin adapter, Ufd1-Npl4, in human cells. We identified a set of chromatin regulators, HUS1, XRCC1, MORF4L1, and the cohesin subunit RAD21 as targets of p97Ufd1-Npl4 We find that RAD21 is ubiquitylated and targeted by p97Ufd1-Npl4 specifically in S phase to remove a subpopulation of cohesin from chromatin. Acute degradation of Ufd1 in S phase, after replication licensing is completed, impedes replication and leads to replication-associated DNA damage. Our findings suggest that a fraction of cohesin rings need to be removed by p97Ufd1-Npl4 from DNA to allow unhindered replication and reveal a critical function of p97 that ensures genome stability.

Cell Cycle Proteins

Biological characterization of Candida parapsilosis haploids induced by voriconazole.

OBJECTIVES: Candida parapsilosis is an important opportunistic fungal pathogen causing serious human infections in nosocomial settings. It has long been thought that C. parapsilosis has a diploid genome with a high homozygosity between chromosome homologs. METHODS: In this study, we report the discovery of C. parapsilosis haploids induced by voriconazole, a triazole with broad antifungal activity against fungal pathogens, in an experimental evolutionary assay. RESULTS: The haploid strains were able to undergo auto-diploidization under in vitro culture conditions or during systemic infection at a low frequency. Compared to the progenitor diploid strain, C. parapsilosis haploid and auto-diploid strains exhibited a reduced ability of invasive growth and biofilm formation. Global transcriptional expression analysis indicated that haploid and auto-diploid strains had a similar transcriptomic profile, which showed a remarkable difference from the progenitor diploid strain perhaps due to the loss of chromosome heterozygosity. Moreover, the haploid and diploid strains had distinct fungal burdens in different animal tissues, suggesting the haploid state could have a colonization advantage over the diploids in certain tissues such as the brain and spleen. CONCLUSIONS: The discovery of C. parapsilosis haploids not only sheds lights on the biology of this important fungal pathogen, but also provides a tool for genetic modifications for the field.

Voriconazole

Insights from changes in NDEV biomarkers of metabolism: effects of PPARγ and GLP1 receptor agonists on brain metabolism.

BACKGROUND: Insulin resistance (IR) is implicated in central nervous system disorders, including depression and Alzheimer's disease (AD). METHODS: We analyzed biological samples from two cohorts of clinical trial participants: (1) participants with unremitted depression after six months of treatment as usual who received pioglitazone (PPARγ agonist, N = 12) or placebo and (2) middle-aged participants at genetic risk for AD who received liraglutide (glucagon-like peptide 1 [GLP1] receptor agonist, N = 15) or placebo. These cohorts, which previously showed treatment-related improvements in peripheral IR, were used to assess the effects of pioglitazone and liraglutide on CNS insulin signaling using neuron-derived extracellular vesicles (NDEVs) as biomarkers. We utilized biological samples to measure biomarkers of IR in NDEVs. Eleven Akt-mTOR pathway proteins were measured before and after 12 weeks of treatment in both groups. RESULTS: Participants who received pioglitazone experienced broader changes, with significant increases in GSK3β (Ser9), mTOR (Ser2448), and RPS6 (Ser235/Ser236; all P ≤ .02) compared with placebo, and 77% of participants showed mTOR (Ser2448) response. Participants who received liraglutide demonstrated significantly increased NDEV-associated phosphorylated Akt (Ser473) and mTOR (Ser2448; P = .04 and P = .025, respectively) compared with placebo, with 40% and 30% of participants in the liraglutide group showing biomarker response in both Akt (Ser473) and mTOR (Ser2448), respectively. These effects appeared relatively independent from changes in fasting plasma insulin and glucose concentration at 120-minutes during the oral glucose tolerance test. DISCUSSION: Our findings demonstrate CNS-specific biomarker responses to both PPARγ agonists and GLP1 receptor agonists.

Humans

Efficacy and Safety of GLP-1 Receptor Agonists for the Management of Antipsychotic-Induced Weight Gain.

OBJECTIVE: The objective of this systematic review and meta-analysis was to compare the efficacy and safety of glucagon-like peptide-1 (GLP-1) receptor agonists for the management of antipsychotic-induced weight gain. DATA SOURCES: A systematic review was conducted following PRISMA methodology through July 2025 that evaluated the efficacy and safety of GLP-1 agonists for the management of antipsychotic-induced weight gain. STUDY SELECTION AND DATA EXTRACTION: Efficacy endpoints were change in body weight (kg), change in body mass index (BMI) (kg/m2), and change in HbA1c (%). The safety endpoint was gastrointestinal (GI) adverse effects. A P-value of 0.05 was considered statistically significant, and heterogeneity was reported as I2. DATA SYNTHESIS: Six studies were included in this systematic review, of which 4 trials were included in the meta-analysis. The difference found between GLP-1 agonists and placebo was a change in weight of -5.85 kg (P = 0.0622, 95% CI = -9.72 to -1.97), a change in BMI of -2.11 kg/m2 (P = 0.7692, 95% CI = -5.51 to 1.29), and a change in HbA1c of -1.58 (P = 0.6659, 95% CI = -4.75 to 1.58). The overall risk ratio for a patient to experience a GI-related adverse effect when taking a GLP-1 agonist compared to placebo was 1.83 (95% CI = 1.42 to 2.37). RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: While the efficacy endpoints did not reach significance, this meta-analysis shows that select GLP-1 receptor agonists may be used to promote weight loss in patients taking antipsychotics. Controlling antipsychotic-induced weight gain helps patients remain adherent to therapeutic doses of their antipsychotic medications. CONCLUSION: The use of certain GLP-1 agonists may be considered to help promote weight loss in patients experiencing antipsychotic-induced weight gain.

Humans

Efficacy and Safety of the C3 Inhibitor Pegcetacoplan in Paroxysmal Nocturnal Hemoglobinuria: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the efficacy and safety of the complement C3 inhibitor pegcetacoplan in patients with paroxysmal nocturnal hemoglobinuria (PNH). METHODS: PubMed, Embase, Web of Science, and Cochrane Library were systematically searched for studies reporting pegcetacoplan use in PNH. Outcomes included transfusion-requirement, hemoglobin normalization, mean hemoglobin levels, lactate dehydrogenase normalization, reticulocyte count normalization, and safety endpoints. Pooled proportions with 95% confidence intervals were calculated using random-effects models, and heterogeneity was assessed using the I2 statistic. RESULTS: Five studies comprising 271 patients were included. Transfusion avoidance was observed in 80.6% of patients, with a pooled transfusion-requirement rate of 19.4%. LDH normalization occurred in 68.5% of patients (I2 = 0%). Hemoglobin normalization was observed in 42.9%, while reticulocyte count normalization reached 66%. Any-grade adverse events occurred in 83.5% of patients, most commonly pyrexia, headache, and dizziness. Serious adverse events occurred in 16.6%, decreasing to 12% after sensitivity analysis. Breakthrough hemolysis was reported in 14.8%, and infections in 17%. CONCLUSION: Pegcetacoplan demonstrates consistent efficacy signals across key hematologic endpoints and an acceptable safety profile, supporting its potential role as an important therapeutic option, particularly in patients with persistent extravascular hemolysis despite C5 inhibition.

Humans

Diabetic macular edema and GLP-1 receptor agonist use: a systematic review and meta-analysis.

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are widely used for type II diabetes and obesity because of their cardiometabolic benefits. However, concerns regarding potential ocular adverse effects, particularly diabetic macular edema (DME), have prompted the need to clarify their retinal safety. METHODS: A systematic review and meta-analysis study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology statements (PROSPERO registration: CRD420251176164). MEDLINE (Ovid), EMBASE (Ovid), CENTRAL (Ovid), Web of Science, and PubMed were searched from inception to October 24, 2025. Randomized trials and observational cohort or case-control studies, including individuals with diabetes without baseline DME and exposed to GLP-1RAs were eligible. Two reviewers independently screened studies, extracted data, and assessed risk of bias using ROBINS-I. Certainty of evidence was evaluated using Grading of Recommendations, Assessment, Development, and Evaluation. Random-effects models were used to pool incidence proportions and hazard ratios (HRs). RESULTS: Thirteen retrospective cohort studies (2021-2025) using large real-world databases were included. Across 6 studies, the pooled proportion of incident DME among GLP-1RA users was 0.14 (95% CI: 0.07-0.23; I² = 99.8%). Compared with mixed antihyperglycemic therapies, GLP-1RA use was not associated with increased DME risk (pooled HR: 0.81, 95% CI: 0.52-1.26). GLP-1RAs were associated with a higher relative risk of DME compared with sodium-glucose cotransporter-2 inhibitors (HR: 1.50, 95% CI: 1.17-1.94) but not compared with dipeptidyl peptidase-4 inhibitors (HR: 0.90, 95% CI: 0.69-1.19). Evidence certainty was very low. CONCLUSION: Current low-certainty observational evidence does not support an overall increased risk of DME with GLP-1RA use. Prospective studies are needed to clarify comparative retinal safety.

Humans

Swab Testing to Optimize Pneumonia Treatment With Empiric Vancomycin: A Randomized Controlled Trial.

BACKGROUND: Fear of methicillin-resistant Staphylococcus aureus (MRSA) as a cause of community-acquired pneumonia (CAP) frequently leads to empiric vancomycin coverage. Data evaluating the use of MRSA polymerase chain reaction (PCR) nasal swab testing to guide vancomycin de-escalation is limited for patients in the intensive care unit (ICU). METHODS: Swab Testing to Optimize Pneumonia Treatment With Empiric Vancomycin (STOP-Vanc) is a pragmatic, prospective, single-center, non-blinded randomized trial in which adult ICU patients with suspicion of CAP were randomized 1:1 to receive usual care either with (intervention) or without (control) the addition of MRSA nares PCR testing following ICU admission. The primary outcome was vancomycin-free hours alive, defined as the expected number of hours alive and free of vancomycin use within the first 7 days of trial enrollment as estimated using a longitudinal proportional odds state transition model adjusted for baseline covariates. RESULTS: A total of 277 adult ICU patients were randomized. Methicillin-resistant Staphylococcus aureus PCR nasal swab testing had a negative predictive value (NPV) of 98.9% in the intervention arm. The primary endpoint, vancomycin-free hours alive, was 105.7 in the control arm and 109.7 in the intervention arm (adjusted difference, 4 hours; 95% CI, -9.5-18.2; P = .458). CONCLUSIONS: Despite MRSA PCR nasal swab testing demonstrating a high NPV in this critically ill population, MRSA PCR nasal swab testing did not decrease the duration of vancomycin use or 30-day mortality among ICU patients with suspected CAP. Additional clinician education and antimicrobial stewardship interventions might be needed to reduce vancomycin use in this patient population. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov NCT06272994 (STOP-Vanc).

Humans

Insulin, Semaglutide and Dapagliflozin in Adults With Type 1 Diabetes: Design and Methods of Triple Therapy for Type 1 Diabetes (TTT1)-An International Phase 3 Clinical Trial.

AIMS: Attaining target glycaemia can be a challenge in Type 1 Diabetes (T1D) due to insulin-induced weight gain. Adjunct therapy with modern glucose-lowering agents developed for type 2 diabetes (T2D) has great potential but may be insufficiently efficacious and carries risks of hypoglycaemia and ketosis. We designed the first Phase 3 clinical trial to assess the efficacy and safety of adding a Glucagon-Like Peptide 1 receptor agonist (GLP-1RA) and a Sodium-Glucose Co-transporter (SGLT2) Inhibitor to insulin therapy in overweight and obese adults with T1D and glycaemia above target (HbA1c 7.5%-11.0% inclusive) (NCT03899402). MATERIALS AND METHODS: In Period 1, participants are randomized 2:1 (open label) for 26 weeks to semaglutide and insulin (uptitrated to 1.0 mg weekly) or standard insulin therapy. In Period 2, those randomized to semaglutide and insulin in Period 1 are further randomized (double-blind) for 26 weeks to dapagliflozin (10 mg daily) or placebo, in addition to semaglutide. The primary objective is to compare change in HbA1c on 'triple therapy' (dapagliflozin, semaglutide and insulin) with 'dual therapy' (placebo, semaglutide and insulin). Secondary objectives include comparisons of triple therapy with standard insulin therapy and dual therapy (semaglutide and insulin) with standard insulin therapy. Safety outcomes include hypoglycaemia and ketosis. A sample size recalculation during the trial based on analysis of masked data revised the original recruitment target from 114 to 82 participants. CONCLUSION: The TTT1 trial will provide clinically useful information on combination adjunct therapy in the treatment of T1D.

Humans

Azithromycin-resistant Salmonella enterica Typhi with AcrB R717L/Q mutations in the United States.

BACKGROUND AND OBJECTIVES: Azithromycin is a critical oral treatment for typhoid fever caused by Salmonella enterica serovar Typhi (Salmonella Typhi), since XDR has rendered other first-line treatment options ineffective. Azithromycin resistance conferred by amino acid changes in AcrB, an AcrAB-TolC efflux pump component, represents an emerging public health concern. Leveraging phenotypic and genotypic data from U.S. Salmonella Typhi surveillance systems, this study describes the prevalence, phenotype and genomic epidemiology of Salmonella Typhi with AcrB mutations in U.S. patients since the first detection in 2015. METHODS: AST and WGS data of >3000 Salmonella Typhi isolates were used to identify all cases with an AcrB mutation in the United States (2015-2025). We calculated annual prevalence and MIC ranges. Phylogenetic analysis was used to contextualize U.S. cases of Salmonella Typhi with an AcrB mutation within all globally reported cases. RESULTS: While the prevalence of AcrB mutations in the United States is low (1.5%), it has risen significantly in recent years, from 0.2% in 2016-2022 to 2.2% in 2023-2025. This increase is predominantly driven by clonal expansion of existing strains circulating in South Asia. AcrB mutations do not reliably confer resistance to azithromycin (MIC ≥ 32 mg/L), complicating clinical interpretation. CONCLUSIONS: The prevalence of AcrB mutations in Salmonella Typhi is increasing in the United States, and likely globally, given that U.S. data function as an informal proxy for regions without routine surveillance infrastructure. Clinical outcomes data are needed to inform Salmonella Typhi treatment guidelines and potentially amend clinical breakpoints for azithromycin.

Journal Article

Depression and amyloid-β across CSF, PET, and plasma biomarkers: a systematic review and meta-analysis.

Alzheimer's disease is increasingly defined by biomarker evidence of amyloid-β and tau pathology, sharpening questions about whether late-life depression contributes to, or instead reflects, this pathology. We conducted a systematic review and meta-analysis of studies published between 2000 and 2025 that compared amyloid-β biomarkers in adults with and without depression, with depression defined by validated clinical diagnoses or symptom rating scales. Twenty-four studies were included, spanning three biomarker sources: cerebrospinal fluid, positron emission tomography imaging, and plasma. Across all sources, the pooled difference in amyloid-β burden between depressed and non-depressed individuals was small and clustered near zero, indicating only a weak, statistically non-significant tendency toward higher amyloid in depression. When the three sources were examined separately, each yielded a similar near-null result, although between-study heterogeneity was considerable for cerebrospinal fluid and plasma and moderate for imaging. Importantly, a prespecified subgroup analysis showed that imaging results diverged by quantification method: studies using the simpler standardized uptake value ratio clustered around zero, whereas the smaller group of studies using kinetic distribution volume ratio modelling showed a significant positive association, suggesting that methodological choices critically influence the observed relationship. Taken together, these findings indicate that depression is not consistently accompanied by greater amyloid-β burden across widely used biomarker platforms. The distribution volume ratio signal nonetheless raises the possibility of subtle associations that cruder methods may obscure, and suggests that depression may shape Alzheimer's disease trajectories more by modifying the clinical impact of amyloid than by altering its amount.

Humans

Pharmacokinetics of injectable favipiravir: phase I, randomized, double-blind, placebo-controlled study in healthy East Asian subjects.

Favipiravir, an oral antiviral medication, has been approved in Japan for the treatment of patients with novel or re-emerging influenza and severe fever with thrombocytopenia syndrome (SFTS). Randomized, double-blind, placebo-controlled trials were conducted in an East Asian population to characterize the pharmacokinetics and tolerability of an injectable favipiravir formulation. In the single-ascending dose trial, subjects received a single intravenous (IV) dose of 300-2,400 mg of favipiravir. In the multiple dose trial, 1,800 mg was administered twice daily on the first day, followed by 800 mg twice daily for the subsequent 10 days, which is the approved tablet dose for SFTS in Japan. This multiple-dose trial was divided into a cohort receiving intravenous administration throughout the treatment period (IV cohort) and a cohort switching to oral administration from Day 6 (Switching cohort). After a single administration of ≤2,400 mg, the pharmacokinetic parameters increased in a dose-dependent manner but showed slight deviation from linearity. The geometric mean maximum plasma concentration following a single 2,400 mg dose was 126 (range: 110 to 138) μg/mL. In the IV cohort, the trough (at 12 h post-dose) plasma concentrations were maintained at approximately 85 μg/mL after Day 2. These concentrations were approximately 20% higher than those achieved with the same oral doses. In the Switching cohort, these concentrations were maintained throughout the treatment. No serious adverse events were observed. These findings support advancing injectable favipiravir into clinical evaluation.CLINICAL TRIALSThis study is registered with the Japan Registry of Clinical Trials as jRCT2071210042 and jRCT2071210126.

Humans

Ruling out pediatric bacterial epididymo-orchitis with urinalysis - The case for minimizing unnecessary antibiotic prescription.

INTRODUCTION: Epididymo-orchitis in pediatric patients is predominantly non-bacterial, often stemming from viral or reactive etiologies. Despite guidelines recommending conservative management for non-bacterial cases, antibiotic overtreatment remains prevalent in the outpatient setting. We evaluated the diagnostic accuracy of urinalysis in ruling out bacterial infection to support antibiotic stewardship in this population. METHODS: We conducted a cross-sectional diagnostic accuracy study using electronic health records from a large health maintenance organization in Israel. The cohort included patients younger than 18 years with a diagnosis of epididymo-orchitis or clinically overlapping entities (acute scrotum, appendage torsion) who had paired urinalysis and urine culture results within one week of diagnosis. Logistic regression and ROC curve analysis were performed to assess the ability of urinalysis parameters to predict positive urine cultures. RESULTS: Of 682 eligible cases, confirmed bacterial infection was rare, occurring in only 17 patients (2.5%). Nitrite positivity was the strongest independent predictor of infection (OR 43.98; p < 0.001). A prediction model incorporating all urinalysis parameters yielded an area under the curve (AUC) of 0.825 and achieved a 97.7% classification accuracy for correctly predicting negative cultures. Despite the low prevalence of infection, antibiotics were prescribed in 237 cases (34.7%). Urinary anatomic abnormalities were significantly associated with culture positivity. CONCLUSIONS: Bacterial coinfection in pediatric epididymo-orchitis is uncommon. Urinalysis serves as a highly accurate screening tool to rule out bacterial etiology. A negative urinalysis supports withholding antibiotics in this setting, reserving treatment for children with positive markers or known anatomic abnormalities. This evidence-based approach This evidence-based approach has the potential to reduce unnecessary antibiotic exposure, however prospective studies are needed to validate these findings before broad implementation.

Humans

Cefoxitin versus cefotaxime as empirical treatment of spontaneous bacterial peritonitis in liver cirrhotic patients: randomized controlled clinical trial.

BACKGROUND: Spontaneous bacterial peritonitis (SBP) is a severe complication of cirrhosis requiring immediate empirical antibiotic therapy. Third-generation cephalosporins are the traditional agents of choice; however, increasing clinical failure rates necessitate the evaluation of alternative antibiotics to ensure optimal therapeutic outcomes. The aim was to investigate the efficacy of cefoxitin versus cefotaxime for SBP treatment. METHODS: A randomized clinical trial was conducted on 140 cirrhotic patients with community-acquired SBP at Al-Rajhy Liver University Hospital, Assiut, Egypt. Patients were randomized to receive either cefotaxime (n&#x200a;=&#x200a;70) or cefoxitin (n&#x200a;=&#x200a;70), 2&#x2005;g every 8&#x2005;h for 5&#x2005;days. Polymorphonuclear neutrophil (PMN) counts were measured upon admission, on Day 2 and on Day 5. Clinical response rates at Days 2 and 5, development of hepatorenal syndrome, length of stay and mortality were assessed. RESULTS: According to intention-to-treat analysis, clinical response rates at Day 2 were 74.2% in the cefotaxime group and 80% in the cefoxitin group, while at Day 5, they were 71.4% and 74.3%, respectively (P&#x200a;=&#x200a;0.704). The PMN counts at Days 0, 2 and 5 showed no significant differences between the cefotaxime and cefoxitin groups (P&#x200a;=&#x200a;0.889, 0.909 and 0.360, respectively). The incidence of hepatorenal syndrome was 7.1% in the cefotaxime group compared with 8.6% in the cefoxitin group (P&#x200a;=&#x200a;0.753), and mortality was 15.7% and 12.9%, respectively (P&#x200a;=&#x200a;0.629). CONCLUSIONS: Cefoxitin showed comparable effectiveness to cefotaxime but may be utilized in selected clinically stable SBP patients.

Humans

Contribution of the Arg-33-His replacement in the histidine kinase CpxA to carbapenem and cefiderocol resistance in Serratia marcescens.

OBJECTIVE: The Serratia marcescens ROT_R clinical isolate, which was resistant to almost all &#x3b2;-lactams, including cefiderocol (4 mg/L), was recovered from a neonate 2 months after the isolation of the S. marcescens ROT_S strain that was susceptible to extended-spectrum cephalosporins (ESCs). In this study, we attempted to decipher the mechanism of resistance displayed by the ROT_R isolate. METHODS: The genomes of ROT_S and ROT_R were sequenced using the Illumina and the Oxford Nanopore Technologies. Long and short reads were assembled together, giving rise to a circularized hybrid genome. RESULTS: Genomic comparison between ROT_S and ROT_R disclosed only one mutation (G98A) in the cpxA gene of ROT_R, which led to the Arg-33-His substitution in the histidine kinase of the two-component system CpxA/CpxR. The cpxA alleles of ROT_S and ROT_R were amplified and cloned, thus giving rise to the pCpxA_WT and pCpxA_R33H recombinant plasmids, respectively, which were subsequently introduced into the S. marcescens HatR recipient strain, which lacks functional CpxA. The S. marcescens HatR (pCpxA_R33H) recombinant clone, which produced the altered CpxA_R33H variant, differed from the S. marcescens HatR (pCpxA_WT) recombinant clone, which produced the wild-type CpxA, by enhanced MICs of carbapenems and ESCs, including cefiderocol (1 mg/L). CONCLUSIONS: This study demonstrates that CpxA alteration, such as Arg-33-His substitution, can contribute to cefiderocol resistance. Although it increases slightly the MIC of cefiderocol without resulting per se in clinical resistance, it can contribute, in combination with other additional mechanisms, to achieve a high level of resistance to this siderophore cephalosporin.

Cefiderocol

A Randomized Clinical Trial to Compare Moxifloxacin Versus Azithromycin for the Treatment of Mycoplasma genitalium: The FARTHEST Study.

BACKGROUND: Mycoplasma genitalium (MG) is increasingly characterized by high rates of macrolide and fluoroquinolone resistance. International guidelines recommend resistance-guided therapy; however, access to genotypic testing is limited, and randomized trial evidence is lacking. We assessed the efficacy of moxifloxacin and azithromycin without resistance assays. METHODS: This monocentric, open-label, superiority, randomized controlled trial enrolled adults with MG infection detected by multiplex PCR, randomized 1:1 to receive moxifloxacin 400 mg daily for 10 days or azithromycin 500 mg daily for 6 days. A test of cure was performed &#x2265;28 days after treatment completion. The primary endpoint was microbiological cure in the intention-to-treat (ITT) and per-protocol (PP) populations. Subgroup analyses assessed symptomatic versus asymptomatic infections, doxycycline exposure, re-treatment, and sexual behavior. RESULTS: Among 358 randomized participants, 87.0% of those treated with moxifloxacin and 61.2% of those treated with azithromycin achieved microbiological cure in the ITT analysis (absolute risk difference 25.8%, 95% CI 16.5, 35.2). The superiority of moxifloxacin was confirmed in the ITT and PP populations. Moxifloxacin remained superior across most subgroups, whereas azithromycin showed comparable efficacy only among heterosexual individuals. Doxycycline coadministration did not improve outcomes. Both regimens were well tolerated, with only one case of discontinuation. CONCLUSIONS: Moxifloxacin demonstrated superior efficacy compared to azithromycin for treating MG infection in the absence of resistance testing. These randomized data support the use of moxifloxacin as a first-line option when resistance assays are unavailable and may inform treatment strategies.

Humans

A prospective pharmacokinetic interaction study between rifampicin and fusidic acid for the treatment of staphylococcal infections.

OBJECTIVE: Fusidic acid with rifampicin is used for the treatment of severe staphylococcal infection, particularly prosthetic joint infections. Previous studies using twice daily fusidic acid showed rifampicin increases fusidic acid clearance, potentially causing sub-therapeutic concentrations. It is uncertain whether this occurs with three-times daily dosing. This study sought to re-evaluate this potential drug-drug interaction. METHODS: In this prospective, open-label drug-drug interaction population pharmacokinetic (PK) study, participants were randomized to receive fusidic acid or rifampicin for 24&#x2005;hours, followed by combination therapy for the duration of treatment. Drug concentration assays used liquid-chromatography mass spectroscopy on dried blood spots. Population PK models were built for fusidic acid, rifampicin and 25-desacetyl rifampicin. RESULTS: Ten participants were recruited. Inter-individual variability for both absorption (98.1%) and clearance (77.8%) were high for fusidic acid. A population pharmacokinetic model for fusidic acid revealed that early autoinhibition dominated over later rifampicin-mediated induction, resulting in a net decrease in fusidic acid clearance. The mean fusidic acid area under the curve during each dosing interval (AUC&#x3c4;) at steady state was 1.76-fold [0.049, 34.918] higher relative to Day 1, despite high uncertainty.Large inter-individual (110%) variability in absorption was observed for rifampicin. There was no apparent effect on rifampicin metabolism by fusidic acid co-administration, however, fusidic acid decreased clearance of 25-desacetyl rifampicin. CONCLUSION: In patients treated with fusidic acid three times daily in combination with rifampicin, autoinhibition potentially counteracted rifampicin induction such that fusidic acid concentrations were not reduced. Rifampicin clearance was not affected by fusidic acid, but 25-desacetyl rifampicin clearance was decreased. There was large inter-individual variability in the observed concentrations and final parameter estimates.

Fusidic Acid