Testing the feasibility of mobile ecological momentary assessment for symptom burden and management among metastatic cancer patients.

Background: Individuals who have metastatic cancer experience substantial physical and psychological distress (e.g., pain, depression, anxiety) from their disease and its treatment compared to patients with less advanced disease. As the burden of symptoms varies over time, ecological momentary assessment (EMA) may be used to better understand patients' symptom trajectories, complimenting traditional longitudinal data collection methods. However, few have used EMA in patients with metastatic disease. The current study adds to the existing literature by exploring interrelated, common cancer-related symptoms of pain, anxiety, and depression and use of cannabis-based products, opioid medications, other (nonopioid) pain medications, and medications for anxiety or depression. Methods: An eight-day prospective observational feasibility study was conducted among 50 patients with metastatic cancer recruited from seven solid cancer clinics at The Ohio State University Comprehensive Cancer Center. Participants completed a week of interval-contingent mobile EMA, administered daily at 9 a.m., 3 p.m., and 8 p.m., and a comprehensive interviewer-administered questionnaire on Day 8. Participants were queried on their symptom burden and management strategies (i.e., use of medications and cannabis). We considered EMA to be feasible if a priori retention (80%) and adherence goals (75%) were met. Results: Seventy-nine percent of eligible patients contacted enrolled in the study (n = 50 of 63). Among those enrolled, 92% were retained through Day 8 and 80% completed >90% of EMAs, exceeding a priori objectives. Participants' average pain, anxiety, and depressive symptoms across the week of EMA ranged from 1.7 to 1.8 (1 to 5 scale). Symptoms varied little by day or time of administration. On Day 8, significant proportions of participants reported past-week use of medications and cannabis for symptom management. Conclusions: Participants exceeded a priori adherence and retention objectives, indicating that mobile EMA is feasible among metastatic cancer patients, addressing a gap in the existing literature and informing future research. Restricting eligibility to participants with a minimum cutoff of symptom burden may be warranted to increase observations of symptom variability and provide opportunities for future health interventions. Future research is needed to test the acceptability and quality of data over a longer study period in this patient population.

A Comprehensive Review of Recent Research into the Effects of Antimicrobial Peptides on Biofilms-January 2020 to September 2023.

Microbial biofilm formation creates a persistent and resistant environment in which microorganisms can survive, contributing to antibiotic resistance and chronic inflammatory diseases. Increasingly, biofilms are caused by multi-drug resistant microorganisms, which, coupled with a diminishing supply of effective antibiotics, is driving the search for new antibiotic therapies. In this respect, antimicrobial peptides (AMPs) are short, hydrophobic, and amphipathic peptides that show activity against multidrug-resistant bacteria and biofilm formation. They also possess broad-spectrum activity and diverse mechanisms of action. In this comprehensive review, 150 publications (from January 2020 to September 2023) were collected and categorized using the search terms 'polypeptide antibiotic agent', 'antimicrobial peptide', and 'biofilm'. During this period, a wide range of natural and synthetic AMPs were studied, of which LL-37, polymyxin B, GH12, and Nisin were the most frequently cited. Furthermore, although many microbes were studied, Staphylococcus aureus and Pseudomonas aeruginosa were the most popular. Publications also considered AMP combinations and the potential role of AMP delivery systems in increasing the efficacy of AMPs, including nanoparticle delivery. Relatively few publications focused on AMP resistance. This comprehensive review informs and guides researchers about the latest developments in AMP research, presenting promising evidence of the role of AMPs as effective antimicrobial agents.

First Report of Colistin-Resistant Escherichia coli Carrying mcr-1 IncI2(delta) and IncX4 Plasmids from Camels (Camelus dromedarius) in the Gulf Region.

Addressing the emergence of antimicrobial resistance (AMR) poses a significant challenge in veterinary and public health. In this study, we focused on determining the presence, phenotypic background, and genetic epidemiology of plasmid-mediated colistin resistance (mcr) in Escherichia coli bacteria isolated from camels farmed in the United Arab Emirates (UAE). Fecal samples were collected from 50 camels at a Dubai-based farm in the UAE and colistin-resistant Gram-negative bacilli were isolated using selective culture. Subsequently, a multiplex PCR targeting a range of mcr-genes, plasmid profiling, and whole-genome sequencing (WGS) were conducted. Eleven of fifty camel fecal samples (22%) yielded colonies positive for E. coli isolates carrying the mcr-1 gene on mobile genetic elements. No other mcr-gene variants and no chromosomally located colistin resistance genes were detected. Following plasmid profiling and WGS, nine E. coli isolates from eight camels were selected for in-depth analysis. E. coli sequence types (STs) identified included ST7, ST21, ST24, ST399, ST649, ST999, and STdaa2. Seven IncI2(delta) and two IncX4 plasmids were found to be associated with mcr-1 carriage in these isolates. These findings represent the first identification of mcr-1-carrying plasmids associated with camels in the Gulf region. The presence of mcr-1 in camels from this region was previously unreported and serves as a novel finding in the field of AMR surveillance.

Analysing responsible innovation along a value chain-A single-cell protein case study.

The British Standards Institution's Publicly Available Specification 440 (PAS 440) provides a Responsible Innovation Framework (RIF) that companies can use to continuously monitor the societal, environmental and health benefits and risks of their innovations, as well as relevant changes to the supply chain and regulations. PAS 440 is intended to help companies achieve the benefits of innovation in a timely manner and avoid any potential harm or unintended misuse of a new product, process or service. Here, the authors have applied the PAS 440 RIF to a novel single-cell protein (SCP) animal feed ingredient taking into consideration the perspectives of the value chain partners (VCPs), companies and laboratories involved in an Innovate UK research project. The authors' findings show how VCPs can use PAS440 to demonstrate that they are innovating responsibly. Using this approach to responsible innovation along the value chain-from manufacturing scale-up, through regulatory approval, to incorporation in animal feed and from there to food on supermarket shelves-can support the development of innovations that contribute to the economic and environmental sustainability of the animal feed sector. The authors conclude that the PAS 440 Guide can facilitate the progress of a new product throughout a value chain and contribute to coordinating responsible behaviour among companies involved in the value chain.

Current cannabis use and pain management among US cancer patients.

BACKGROUND: National studies reporting the prevalence of cannabis use have focused on individuals with a history of cancer without distinction by their treatment status, which can impact symptom burden. While pain is a primary motivation to use cannabis in cancer, the magnitude of its association with cannabis use remains understudied. METHODS: We examined cannabis use and pain management among 5523 respondents of the Behavioral Risk Factor Surveillance System with a cancer history. Survey-weighted prevalence proportions of respondents' cannabis use are reported, stratified on cancer treatment status. Regression models estimated odds ratios (ORs) and 95% confidence intervals (CIs) of cancer-related pain and cannabis use. RESULTS: Cannabis use was slightly more prevalent in those undergoing active treatment relative to those who were not undergoing active treatment (9.3% vs. 6.2%; P=0.05). Those under active treatment were more likely to use cannabis medicinally (71.6% vs. 50.0%; P=0.03). Relative to those without cancer-related pain, persons with pain under medical control (OR 2.1, 95% CI, 1.4-3.2) or uncontrolled pain were twice as likely to use cannabis (OR 2.0, 95% CI, 1.1-3.5). CONCLUSIONS: Use of cannabis among cancer patients may be related to their treatment and is positively associated with cancer-related pain. Future research should investigate the associations of cannabis use, symptom burden, and treatment regimens across the treatment spectrum to facilitate interventions.

Associations of Cancer Patients' Demographic and Clinical Characteristics With Cannabis-Related Interest and Behaviors.

Background: Cannabis interest and use is increasing in the United States, yet research on its use among cancer patients is limited. Methods: Individuals with cancer completed an anonymous cross-sectional questionnaire. Multivariable logistic regressions estimated odds ratios (OR) between patients' demographic and clinical characteristics with cannabis-related interest, current use, and provider recommendation. Results: Participants (n = 943) were, on average, 61.7 years old. Older patients were less likely to use cannabis products (OR = 0.42, confidence interval [95% CI]: 0.26-0.69) and less likely to be interested in cannabis (OR = 0.60, 95% CI: 0.44-0.84) than younger patients. Those with higher education were less likely to be using cannabis (OR = 0.41, 95% CI: 0.25-0.67) and less likely to have received a provider recommendation of cannabis use than the least educated (OR = 0.38, 95% CI: 0.19-0.76). Cancer spread and type were significant correlates of provider recommendation of cannabis use. Conclusions: Additional research is warranted to better understand cancer patients' motivations for cannabis use and interest.

In vitro activity of novel apramycin-dextran nanoparticles and free apramycin against selected Dutch and Pakistani Klebsiella pneumonia isolates.

Klebsiella pneumoniae are bacteria associated with respiratory tract infections and are increasingly becoming resistant to antibiotics, including carbapenems. Apramycin is a veterinary antibiotic that may have the potential to be re-purposed for use in human health, for example, for the treatment of respiratory tract infections after coupling to inhalable nanoparticles. In the present study, the antibiotic apramycin was formulated with single chain polymeric nanoparticles and tested in free and formulated forms against a set of 13 Klebsiella pneumoniae isolates (from the Netherlands and Pakistan) expressing different aminoglycoside resistance phenotypes. Minimum Inhibitory Concentration, Time Kill Kinetics and biofilm experiments were performed providing evidence for the potential efficacy of apramycin and apramycin-based nanomedicines for the treatment of human Klebsiella pneumonia infections.

Expert guidance on target product profile development for AMR diagnostic tests.

Diagnostics are widely considered crucial in the fight against antimicrobial resistance (AMR), which is expected to kill 10 million people annually by 2030. Nevertheless, there remains a substantial gap between the need for AMR diagnostics versus their development and implementation. To help address this problem, target product profiles (TPP) have been developed to focus developers' attention on the key aspects of AMR diagnostic tests. However, during discussion between a multisectoral working group of 51 international experts from industry, academia and healthcare, it was noted that specific AMR-related TPPs could be extended by incorporating the interdependencies between the key characteristics associated with the development of such TPPs. Subsequently, the working group identified 46 characteristics associated with six main categories (ie, Intended Use, Diagnostic Question, Test Description, Assay Protocol, Performance and Commercial). The interdependencies of these characteristics were then identified and mapped against each other to generate new insights for use by stakeholders. Specifically, it may not be possible for diagnostics developers to achieve all of the recommendations in every category of a TPP and this publication indicates how prioritising specific TPP characteristics during diagnostics development may influence (or not) a range of other TPP characteristics associated with the diagnostic. The use of such guidance, in conjunction with specific TPPs, could lead to more efficient AMR diagnostics development.

Marijuana and Cannabidiol Use Prevalence and Symptom Management Among Patients with Cancer.

Symptoms such as pain, nausea, and anxiety are common in individuals with cancer. Treatment of these issues is often challenging. Cannabis products may be helpful in reducing the severity of these symptoms. While some studies include data on the prevalence of cannabis use among patients with cancer, detailed data remain limited, and none have reported the prevalence of cannabidiol (CBD) use in this population. Adult patients with cancer attending eight clinics at a large, NCI-designated Comprehensive Cancer Center completed a detailed, cannabis-focused questionnaire between 2021 and 2022. Eligible participants were diagnosed with invasive cancer and treated in the past 12 months. Summary statistics were calculated to describe the sample regarding cannabis use. Approximately 15% (n = 142) of consented patients (n = 934) reported current cannabis use (defined as use within the past 12 months). Among which, 75% reported cannabis use in the past week. Among current cannabis users, 39% (n = 56; 6% overall) used CBD products. Current users reported using cannabis a median of 4.5 (interquartile range: 0.6­7.0) days/week, 2.0 (1.0­3.0) times per use/day, and for 3 years (0.8­30.0). Use patterns varied by route of administration. Patients reported moderate to high relief of symptoms with cannabis use. This study is the most detailed to date in terms of cannabis measurement and provides information about the current state of cannabis use in active cancer. Future studies should include complete assessments of cannabis product use, multiple recruitment sites, and diverse patient populations. SIGNIFICANCE: Clinicians should be aware that patients are using cannabis products and perceive symptom relief with its use.

ARTISTRY-7: phase III trial of nemvaleukin alfa plus pembrolizumab vs chemotherapy for platinum-resistant ovarian cancer.

Standard single-agent nonplatinum chemotherapy provides only modest benefit in a small proportion of patients with platinum-resistant/-refractory ovarian cancer, with objective response rates of 6-20% and progression-free survival of ≈3-4 months. Nemvaleukin alfa (nemvaleukin, ALKS 4230) is a novel cytokine designed to capture and expand the therapeutic potential of high-dose interleukin-2 (IL-2) while mitigating its associated toxicity issues. Nemvaleukin preferentially activates cytotoxic CD8+ T cells and natural killer cells with minimal, non-dose-dependent effects on CD4+ regulatory T cells. The global, randomized, open-label, phase III ARTISTRY-7 trial will compare efficacy and safety of nemvaleukin plus pembrolizumab with chemotherapy in patients with platinum-resistant ovarian cancer. The primary end point is investigator-assessed progression-free survival. Clinical Trial Registration: GOG-3063; ENGOT-OV68; NCT05092360 (ClinicalTrials.gov).

In many patients with ovarian cancer who are treated with platinum-based chemotherapy, the tumor comes back after a few months and fails to respond to repeated treatment. This type of disease is called platinum-resistant ovarian cancer (PROC). Researchers are searching for new medicines to help more patients with PROC. One treatment approach that has shown promise in different cancers is called immunotherapy. These medicines work by helping the body's immune system attack cancer cells. One of the immunotherapies being studied is called nemvaleukin. It is designed to trigger specific immune responses that may result in the immune system attacking cancer cells while potentially avoiding other immune responses that can block the attack or cause certain unwanted side effects. Nemvaleukin is being studied in a variety of cancer types. In a worldwide clinical trial called ARTISTRY-7, researchers are investigating how nemvaleukin works in patients with PROC when given with another immunotherapy called pembrolizumab. Patients who participate in this trial will be randomly assigned to one of four treatment groups: the combination of nemvaleukin and pembrolizumab, nemvaleukin by itself, pembrolizumab by itself, or a type of chemotherapy selected by the treating physician. The main purpose of ARTISTRY-7 is to understand whether the combination of nemvaleukin and pembrolizumab helps patients with PROC live longer without their cancer getting worse. At the time of this writing, ARTISTRY-7 is open for new patients to join.

Supplemental B-Vitamins and Risk of Upper Gastrointestinal Cancers in the Women's Health Initiative.

B-vitamins contribute to DNA synthesis, maintenance, and regulation. Few studies have examined associations of supplemental sources of B-vitamins with the incidence of upper gastrointestinal (GI) cancers [including gastric (GCA) and esophageal (ECA) cancers]; the only prior study to comprehensively examine such intakes reported potential elevated risks of ECA. We examined 159,401 postmenopausal women, ages 50-79 years at baseline, including 302 incident GCA and 183 incident ECA cases, over 19 years of follow-up within the Women's Health Initiative observational study and clinic trials. Adjusted Cox regression models estimated hazard ratios (HR) and 95% confidence intervals (CI) for associations of supplemental B-vitamins [riboflavin (B2), pyridoxine (B6), folic acid (B9), or cobalamin (B12)] with GCA and ECA risk, respectively. Although HRs were generally below 1.0, we observed no statistically significant associations between supplemental intakes of any of the evaluated B-vitamins with the risk of GCA or ECA. As the first prospective study to comprehensively assess these associations, our findings do not corroborate prior research indicating potential harm from supplemental B-vitamin intake for upper GI cancer risk. This study adds evidence that supplemental intakes of B-vitamins may be used by postmenopausal women without regard to their relationship with upper GI cancer risk.

Mainstreaming germline genetic testing for patients with pancreatic cancer increases uptake.

Germline genetic testing is recommended for all patients with pancreatic cancer (PC) but uptake rates are low. We implemented a mainstreaming program in oncology clinics to increase testing for PC patients. Genetic counselors trained oncology providers to offer a standardized multigene panel and obtain informed consent using an educational video. Pre-test genetic counseling was available upon request. Otherwise, patients with identified pathogenic variants, strong family history, or questions regarding their results were referred for post-test genetic counseling. We measured rates of testing and genetic counseling visits. From September 2019 to April 2021, 245 patients with PC underwent genetic testing. This represents a 6.5-fold increase in germline testing volume (95% confidence interval 5.2-8.1) compared to previous years. At least one pathogenic or likely pathogenic variant (PV/LPV) was found in 34 (13.9%) patients, including 17 (6.9%) PV/LPVs in high or moderate risk genes and 18 (7.3%) in low risk or recessive genes. Five (2.0%) PVs had implications on treatment selection. 22 of the positive patients (64.7%) and an additional 8 PC patients (1 negative, 3 VUS, and 4 pre-test) underwent genetic counseling during the study period. Genetic counselors saw 2.0 PC patients/month prior to this project, 1.6 PC patients/month during this project, and would have seen 2.2 PC patients/month if all patients with pathogenic variants attended post-test counseling. Conclusions Mainstreaming genetic testing expands access for PC patients without overwhelming genetic counseling resources.

Extended Spectrum- and Carbapenemase-Based ß-Lactam Resistance in the Arabian Peninsula-A Descriptive Review of Recent Years.

Antimicrobial resistance (AMR) is a global problem that also includes countries of the Arabian Peninsula. Of particular concern, is the continuing development of extended-spectrum ß-lactamases (ESBLs) in the countries of this region. Additionally, antibiotic treatment options for ESBL-producing bacteria are becoming limited, primarily due to the continuing development of carbapenem resistance (CR), carbapenems being frequently used to treat such infections. An overview of recent publications (2018-2021) indicates the presence of ESBL and/or CR in patients and hospitals in most countries of the Arabian Peninsula, although the delay between microbial isolation and publication inevitably makes an accurate analysis of the current situation rather difficult. However, there appears to be greater emphasis on CR (including combined ESBL and CR) in recent publications. Furthermore, although publications from Saudi Arabia are the most prevalent, this may simply reflect the increased interest in ESBL and CR within the country. Enhanced ESBL/CR surveillance is recommended for all countries in the Arabian Peninsula.

Randomized, Double-Blind, Placebo-Controlled Phase III Study of Paclitaxel ± Napabucasin in Pretreated Advanced Gastric or Gastroesophageal Junction Adenocarcinoma.

PURPOSE: To compare napabucasin (generator of reactive oxygen species) plus paclitaxel with paclitaxel only in patients with second-line advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma. EXPERIMENTAL DESIGN: In the double-blind, phase III BRIGHTER study (NCT02178956), patients were randomized (1:1) to napabucasin (480 mg orally twice daily) plus paclitaxel (80 mg/m2 i.v. weekly for 3 of 4 weeks) or placebo plus paclitaxel. The primary endpoint was overall survival (OS). Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety. RESULTS: Overall, 714 patients were randomized (napabucasin plus paclitaxel, n = 357; placebo plus paclitaxel, n = 357). 72.1% were male, 74.6% had gastric adenocarcinoma, and 46.2% had peritoneal metastases. The study was unblinded following an interim analysis at 380 deaths. The final efficacy analysis was performed on 565 deaths (median follow-up, 6.8 months). No significant differences were observed between napabucasin plus paclitaxel and placebo plus paclitaxel for OS (6.93 vs. 7.36 months), PFS (3.55 vs. 3.68 months), ORR (16% vs. 18%), or DCR (55% vs. 58%). Grade ≥3 adverse events occurred in 69.5% and 59.7% of patients administered napabucasin plus paclitaxel and placebo plus paclitaxel, respectively, with grade ≥3 diarrhea reported in 16.2% and 1.4%, respectively. CONCLUSIONS: Adding napabucasin to paclitaxel did not improve survival in patients with pretreated advanced gastric or GEJ adenocarcinoma. Consistent with previous reports, the safety profile of napabucasin was driven by manageable gastrointestinal events; grade ≥3 diarrhea occurred at a higher frequency with napabucasin plus paclitaxel versus placebo plus paclitaxel.

Datasets for benchmarking antimicrobial resistance genes in bacterial metagenomic and whole genome sequencing.

Whole genome sequencing (WGS) is a key tool in identifying and characterising disease-associated bacteria across clinical, agricultural, and environmental contexts. One increasingly common use of genomic and metagenomic sequencing is in identifying the type and range of antimicrobial resistance (AMR) genes present in bacterial isolates in order to make predictions regarding their AMR phenotype. However, there are a large number of alternative bioinformatics software and pipelines available, which can lead to dissimilar results. It is, therefore, vital that researchers carefully evaluate their genomic and metagenomic AMR analysis methods using a common dataset. To this end, as part of the Microbial Bioinformatics Hackathon and Workshop 2021, a 'gold standard' reference genomic and simulated metagenomic dataset was generated containing raw sequence reads mapped against their corresponding reference genome from a range of 174 potentially pathogenic bacteria. These datasets and their accompanying metadata are freely available for use in benchmarking studies of bacteria and their antimicrobial resistance genes and will help improve tool development for the identification of AMR genes in complex samples.

Perspectives on the Ethics of Antibiotic Overuse and on the Implementation of (New) Antibiotics.

The continuing rise in global antimicrobial resistance is seen by many governments and international organizations as a major threat to worldwide health. This means that many publications have already described the problems concerning the overuse of currently available antibiotics and potential solutions to this crisis, including the development of new alternatives to antibiotics. However, in this manuscript, the authors approach the subject of increasing global antimicrobial resistance from two perspectives not normally covered by previous publications, namely the ethical use of antibiotics and potential issues relating to the implementation of new antibiotics.

The diagnostic value of nasal microbiota and clinical parameters in a multi-parametric prediction model to differentiate bacterial versus viral infections in lower respiratory tract infections.

BACKGROUND: The ability to accurately distinguish bacterial from viral infection would help clinicians better target antimicrobial therapy during suspected lower respiratory tract infections (LRTI). Although technological developments make it feasible to rapidly generate patient-specific microbiota profiles, evidence is required to show the clinical value of using microbiota data for infection diagnosis. In this study, we investigated whether adding nasal cavity microbiota profiles to readily available clinical information could improve machine learning classifiers to distinguish bacterial from viral infection in patients with LRTI. RESULTS: Various multi-parametric Random Forests classifiers were evaluated on the clinical and microbiota data of 293 LRTI patients for their prediction accuracies to differentiate bacterial from viral infection. The most predictive variable was C-reactive protein (CRP). We observed a marginal prediction improvement when 7 most prevalent nasal microbiota genera were added to the CRP model. In contrast, adding three clinical variables, absolute neutrophil count, consolidation on X-ray, and age group to the CRP model significantly improved the prediction. The best model correctly predicted 85% of the 'bacterial' patients and 82% of the 'viral' patients using 13 clinical and 3 nasal cavity microbiota genera (Staphylococcus, Moraxella, and Streptococcus). CONCLUSIONS: We developed high-accuracy multi-parametric machine learning classifiers to differentiate bacterial from viral infections in LRTI patients of various ages. We demonstrated the predictive value of four easy-to-collect clinical variables which facilitate personalized and accurate clinical decision-making. We observed that nasal cavity microbiota correlate with the clinical variables and thus may not add significant value to diagnostic algorithms that aim to differentiate bacterial from viral infections.

Drivers of genomic loss of heterozygosity in leiomyosarcoma are distinct from carcinomas.

Leiomyosarcoma (LMS) is a rare, aggressive, mesenchymal tumor. Subsets of LMS have been identified to harbor genomic alterations associated with homologous recombination deficiency (HRD); particularly alterations in BRCA2. Whereas genomic loss of heterozygosity (gLOH) has been used as a surrogate marker of HRD in other solid tumors, the prognostic or clinical value of gLOH in LMS (gLOH-LMS) remains poorly defined. We explore the genomic drivers associated with gLOH-LMS and their clinical import. Although the distribution of gLOH-LMS scores are similar to that of carcinomas, outside of BRCA2, there was no overlap with previously published gLOH-associated genes from studies in carcinomas. We note that early stage tumors with elevated gLOH demonstrated a longer disease-free interval following resection in LMS patients. Taken together, and despite similarities to carcinomas in gLOH distribution and clinical import, gLOH-LMS are driven by different genomic signals. Additional studies will be required to isolate and confirm the unique differences in biological factors driving these differences.

Liquid Chromatography-Tandem Mass Spectrometry Analysis Demonstrates a Decrease in Porins and Increase in CMY-2 ß-Lactamases in Escherichia coli Exposed to Increasing Concentrations of Meropenem.

While Extended-Spectrum ß-Lactamases (ESBL) and AmpC ß-lactamases barely degrade carbapenem antibiotics, they are able to bind carbapenems and prevent them from interacting with penicillin-binding proteins, thereby inhibiting their activity. Further, it has been shown that Enterobacterales can become resistant to carbapenems when high concentrations of ESBL and AmpC ß-lactamases are present in the bacterial cell in combination with a decreased influx of antibiotics (due to a decrease in porins and outer-membrane permeability). In this study, a targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed for the detection of the Escherichia coli porins OmpC and OmpF, its chromosomal AmpC ß-lactamase, and the plasmid-mediated CMY-2 ß-lactamase. Bla CMY-2-like positive E. coli isolates were cultured in the presence of increasing concentrations of meropenem, and resistant mutants were analyzed using the developed LC-MS/MS assay, Western blotting, and whole genome sequencing. In five strains that became meropenem resistant, a decrease in OmpC and/or OmpF (caused by premature stop codons or gene interruptions) was the first event toward meropenem resistance. In four of these strains, an additional increase in MICs was caused by an increase in CMY-2 production, and in one strain this was most likely caused by an increase in CTX-M-15 production. The LC-MS/MS assay developed proved to be suitable for the (semi-)quantitative analysis of CMY-2-like ß-lactamases and porins within 4 h. Targeted LC-MS/MS could have additional clinical value in the early detection of non-carbapenemase-producing carbapenem-resistant E. coli.

Progress in Alternative Strategies to Combat Antimicrobial Resistance: Focus on Antibiotics.

Antibiotic resistance, and, in a broader perspective, antimicrobial resistance (AMR), continues to evolve and spread beyond all boundaries. As a result, infectious diseases have become more challenging or even impossible to treat, leading to an increase in morbidity and mortality. Despite the failure of conventional, traditional antimicrobial therapy, in the past two decades, no novel class of antibiotics has been introduced. Consequently, several novel alternative strategies to combat these (multi-) drug-resistant infectious microorganisms have been identified. The purpose of this review is to gather and consider the strategies that are being applied or proposed as potential alternatives to traditional antibiotics. These strategies include combination therapy, techniques that target the enzymes or proteins responsible for antimicrobial resistance, resistant bacteria, drug delivery systems, physicochemical methods, and unconventional techniques, including the CRISPR-Cas system. These alternative strategies may have the potential to change the treatment of multi-drug-resistant pathogens in human clinical settings.