Membrane Lipids Augment Cell Envelope Stress Signaling via the MadRS System to Defend Against Antimicrobial Peptides and Antibiotics in Enterococcus faecalis.

Enterococci have evolved resistance mechanisms to protect their cell envelopes against bacteriocins and host cationic antimicrobial peptides (CAMPs) produced in the gastrointestinal environment. Activation of the membrane stress response has also been tied to resistance to the lipopeptide antibiotic daptomycin. However, the actual effectors mediating resistance have not been elucidated. Here, we show that the MadRS (formerly YxdJK) membrane antimicrobial peptide defense system controls a network of genes, including a previously uncharacterized three gene operon (madEFG) that protects the E. faecalis cell envelope from antimicrobial peptides. Constitutive activation of the system confers protection against CAMPs and daptomycin in the absence of a functional LiaFSR system and leads to persistence of cardiac microlesions in vivo. Moreover, changes in the lipid cell membrane environment alter CAMP susceptibility and expression of the MadRS system. Thus, we provide a framework supporting a multilayered envelope defense mechanism for resistance and survival coupled to virulence.

LiaX is a surrogate marker for cell envelope stress and daptomycin non-susceptibility in Enterococcus faecium.

Daptomycin (DAP) is often used as a first-line therapy to treat vancomycin-resistant Enterococcus faecium infections, but emergence of DAP non-susceptibility threatens the effectiveness of this antibiotic. Moreover, current methods to determine DAP minimum inhibitory concentrations (MICs) have poor reproducibility and accuracy. In enterococci, DAP resistance is mediated by the LiaFSR cell membrane stress response system, and deletion of liaR encoding the response regulator results in hypersusceptibility to DAP and antimicrobial peptides. The main genes regulated by LiaR are a cluster of three genes, designated liaXYZ. In Enterococcus faecalis, LiaX is surface-exposed with a C-terminus that functions as a negative regulator of cell membrane remodeling and an N-terminal domain that is released to the extracellular medium where it binds DAP. Thus, in E. faecalis, LiaX functions as a sentinel molecule recognizing DAP and controlling the cell membrane response, but less is known about LiaX in E. faecium. Here, we found that liaX is essential in E. faecium with an activated LiaFSR system. Unlike E. faecalis, E. faecium LiaX is not detected in the extracellular milieu and does not appear to alter phospholipid architecture. We further postulated that LiaX could be used as a surrogate marker for cell envelope activation and non-susceptibility to DAP. For this purpose, we developed and optimized a LiaX enzyme-linked immunosorbent assay (ELISA). We then assessed 86 clinical E. faecium bloodstream isolates for DAP MICs and used whole genome sequencing to assess for substitutions in LiaX. All DAP-resistant clinical strains of E. faecium exhibited elevated LiaX levels. Strikingly, 73% of DAP-susceptible isolates by standard MIC determination also had elevated LiaX ELISAs compared to a well-characterized DAP-susceptible strain. Phylogenetic analyses of predicted amino acid substitutions showed 12 different variants of LiaX without a specific association with DAP MIC or LiaX ELISA values. Our findings also suggest that many E. faecium isolates that test DAP susceptible by standard MIC determination are likely to have an activated cell stress response that may predispose to DAP failure. As LiaX appears to be essential for the cell envelope response to DAP, its detection could prove useful to improve the accuracy of susceptibility testing by anticipating therapeutic failure.

Emerin regulation of nuclear stiffness is required for fast amoeboid migration in confined environments.

When metastasizing, tumor cells must traverse environments with diverse physicochemical properties. Recently, the cell nucleus has emerged as a major regulator of the transition from mesenchymal to fast amoeboid (leader bleb-based) migration. Here, we demonstrate that increasing nuclear stiffness through elevating lamin A, inhibits fast amoeboid migration in melanoma cells. Importantly, nuclei may respond to force through stiffening. A key factor in this process is the inner nuclear membrane (INM) protein emerin. Accordingly, we determined the role of emerin in regulating fast amoeboid migration. Strikingly, we found that both the up- and downregulation of emerin results in an inhibition of fast amoeboid migration. However, when key Src phosphorylation sites were removed, upregulation of emerin no longer inhibited fast amoeboid migration. Interestingly, as measured by using a Src biosensor, activity of Src was low in cells within a confined environment. Thus, the fast amoeboid migration of melanoma cells depends on the precise calibration of emerin activity.

Multidrug resistance among uropathogenic clonal group A E. Coli isolates from Pakistani women with uncomplicated urinary tract infections.

OBJECTIVE: Multi-drug resistance (MDR) has notably increased in community acquired uropathogens causing urinary tract infections (UTIs), predominantly Escherichia coli. Uropathogenic E. coli causes 80% of uncomplicated community acquired UTIs, particularly in pre-menopausal women. Considering this high prevalence and the potential to spread antimicrobial resistant genes, the current study was conducted to investigate the presence of clinically important strains of E. coli in Pakistani women having uncomplicated cystitis and pyelonephritis. Women belonging to low-income groups were exclusively included in the study. Seventy-four isolates from urine samples were processed, phylotyped, and screened for the presence of two Single Nucleotide Polymorphisms (SNPs) particularly associated with a clinically important clonal group A of E. coli (CgA) followed by antibiotic susceptibility testing and genome sequence analysis. RESULTS: Phylogroup B2 was most prevalent in patients and 44% of isolates were positive for the presence of CgA specific SNPs in Fumarate hydratase and DNA gyrase subunit B genes. Antibiotic susceptibility testing showed widespread resistance to trimethoprim-sulfamethoxazole and extended-spectrum beta-lactamase production. The infection analysis revealed the phylogroup B2 to be more pathogenic as compared to the other groups. The genome sequence of E. coli strain U17 revealed genes encoding virulence, multidrug resistance, and host colonization mechanisms. CONCLUSIONS: Our research findings not only validate the significant occurrence of multidrug-resistant clonal group A E. coli (CgA) in premenopausal Pakistani women suffering from cystitis and pyelonephritis but also reveal the presence of genes associated withvirulence, and drug efflux pumps. The detection of highly pathogenic, antimicrobial-resistant phylogroup B2 and CgA E. coli strains is likely to help in understanding the epidemiology of the pathogen and may ultimately help to reduce the impact of these strains on human health. Furthermore, the findings of this study will particularly help to reduce the prevalence of uncomplicated UTIs and the cost associated with their treatment in women belonging to low-income groups.

Fatty acid binding protein 5 inhibition attenuates pronociceptive cytokine/chemokine expression and suppresses osteoarthritis pain: A comparative human and rat study.

OBJECTIVE: Osteoarthritis (OA) is often accompanied by debilitating pain that is refractory to available analgesics due in part to the complexity of signaling molecules that drive OA pain and our inability to target these in parallel. Fatty acid binding protein 5 (FABP5) is a lipid chaperone that regulates inflammatory pain; however, its contribution to OA pain has not been characterized. DESIGN: This combined clinical and pre-clinical study utilized synovial tissues obtained from subjects with end-stage OA and rats with monoiodoacetate-induced OA. Cytokine and chemokine release from human synovia incubated with a selective FABP5 inhibitor was profiled with cytokine arrays and ELISA. Immunohistochemical analyses were conducted for FABP5 in human and rat synovium. The efficacy of FABP5 inhibitors on pain was assessed in OA rats using incapacitance as an outcome. RNA-seq was then performed to characterize the transcriptomic landscape of synovial gene expression in OA rats treated with FABP5 inhibitor or vehicle. RESULTS: FABP5 was expressed in human synovium and FABP5 inhibition reduced the secretion of pronociceptive cytokines (interleukin-6 [IL6], IL8) and chemokines (CCL2, CXCL1). In rats, FABP5 was upregulated in the OA synovium and its inhibition alleviated incapacitance. The transcriptome of the rat OA synovium exhibited >6000 differentially expressed genes, including the upregulation of numerous pronociceptive cytokines and chemokines. FABP5 inhibition blunted the upregulation of the majority of these pronociceptive mediators. CONCLUSIONS: FABP5 is expressed in the OA synovium and its inhibition suppresses pronociceptive signaling and pain, indicating that FABP5 inhibitors may constitute a novel class of analgesics to treat OA.

A review on endophytic fungi: a potent reservoir of bioactive metabolites with special emphasis on blight disease management.

Phytopathogenic microorganisms have caused blight diseases that present significant challenges to global agriculture. These diseases result in substantial crop losses and have a significant economic impact. Due to the limitations of conventional chemical treatments in effectively and sustainably managing these diseases, there is an increasing interest in exploring alternative and environmentally friendly approaches for disease control. Using endophytic fungi as biocontrol agents has become a promising strategy in recent years. Endophytic fungi live inside plant tissues, forming mutually beneficial relationships, and have been discovered to produce a wide range of bioactive metabolites. These metabolites demonstrate significant potential for fighting blight diseases and provide a plentiful source of new biopesticides. In this review, we delve into the potential of endophytic fungi as a means of biocontrol against blight diseases. We specifically highlight their significance as a source of biologically active compounds. The review explores different mechanisms used by endophytic fungi to suppress phytopathogens. These mechanisms include competing for nutrients, producing antifungal compounds, and triggering plant defense responses. Furthermore, this review discusses the challenges of using endophytic fungi as biocontrol agents in commercial applications. It emphasizes the importance of conducting thorough research to enhance their effectiveness and stability in real-world environments. Therefore, bioactive metabolites from endophytic fungi have considerable potential for sustainable and eco-friendly blight disease control. Additional research on endophytes and their metabolites will promote biotechnology solutions.

Relationship of neutrophil lymphocyte ratio, monocyte lymphocyte ratio and neutrophil monocyte ratio with treatment response in pulmonary tuberculosis patients during intensive phase treatment.

OBJECTIVE: To determine the relationship of Neutrophil Lymphocyte Ratio (NLR), Monocyte Lymphocyte Ratio (MLR), and Neutrophil Monocyte Ratio (NMR) with treatment response in Pulmonary Tuberculosis (PTB) patients during intensive phase treatment (IPT). METHODS: This analytical cross-sectional study was conducted at Ojha Institute of Chest Diseases (OICD), Dow University of Health Sciences, from February to December 2021. 100 patients were enrolled using purposive sampling technique. Both male and female of age 18 and above, rifampicin sensitive newly diagnosed cases of PTB by Acid Fast Bacilli (AFB) microscopy and Gene Xpert MTB/RIF were included. SPSS version 26 was used to analyze data. Numerical data was expressed in median and interquartile range and categorical data was expressed in frequencies and percentages. RESULTS: Out of total 100 patients, 81% (n = 81) showed treatment response with negative AFB Sputum Smear Microscopy (SSM) after 2nd month. Out of 81% (n = 81) of the patients who achieved treatment response, 83.9% (n = 68) also had decreased NLR, 85.2% (n = 69) had decreased MLR and 83.9% (n = 68) had decreased NMR from baseline. However 19% (n = 19) did not achieved treatment response with positive AFB SSM after 2nd month of ATT (Anti tuberculosis treatment), among them 10.52% (n = 2) were INH resistant with no decrease in all the ratios after 2nd month. CONCLUSION: Leukocyte ratios decreased significantly from baseline as PTB was treated in patients who achieved treatment response with negative AFB SSM after two months of ATT and hence these ratios could be used as markers to monitor the treatment response.

Spotlight on El-Zahrawi, Father of Modern Surgery: Reflections on His Impact on Contemporary Medicine and the Need for Greater Medical Education on Pivotal Figures in Medicine.

Issue: For students in the preclinical years of medical school, it is easy to overlook the narrative component of medicine and become occupied with learning the vast sea of information about the human body. There are limited, if any, options to learn about historical figures in medicine and how they can inform our future in clinical medicine. Evidence: There is an apparent lack of education offered on pivotal figures in medicine across many institutions. The few instances that medical history has been incorporated into the curriculum are further discussed. Implications: In order to incorporate cultural competency in our delivery of care, it is important to consider the diversity of the population we will be serving and how we can prepare to help patients feel heard in their unique issues. In this paper, we propose learning about the true history of certain medical practices, rather than the "colonial" version often utilized in textbooks and lectures, as a means of diversifying students' perspectives of the origins of these practices as well as giving credit where it is due. The time period during which many of these medical practices were cultivated is referred to as the Islamic Golden Age, but scholars who made contributions belonged to many different faiths and cultural backgrounds. El-Zahrawi was a Muslim physician whose principal work, Kitab-at-Tasrif, contains topics on medicine, surgery, midwifery, pharmacology, therapeutics, diet, psychotherapy, and medical chemistry. He pioneered numerous techniques in surgery and invented surgical devices that are still used to this day.

Prolonged vs Intermittent Infusions of ß-Lactam Antibiotics in Adults With Sepsis or Septic Shock: A Systematic Review and Meta-Analysis.

Importance: There is uncertainty about whether prolonged infusions of ß-lactam antibiotics improve clinically important outcomes in critically ill adults with sepsis or septic shock. Objective: To determine whether prolonged ß-lactam antibiotic infusions are associated with a reduced risk of death in critically ill adults with sepsis or septic shock compared with intermittent infusions. Data Sources: The primary search was conducted with MEDLINE (via PubMed), CINAHL, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov from inception to May 2, 2024. Study Selection: Randomized clinical trials comparing prolonged (continuous or extended) and intermittent infusions of ß-lactam antibiotics in critically ill adults with sepsis or septic shock. Data Extraction and Synthesis: Data extraction and risk of bias were assessed independently by 2 reviewers. Certainty of evidence was evaluated with the Grading of Recommendations Assessment, Development and Evaluation approach. A bayesian framework was used as the primary analysis approach and a frequentist framework as the secondary approach. Main Outcomes and Measures: The primary outcome was all-cause 90-day mortality. Secondary outcomes included intensive care unit (ICU) mortality and clinical cure. Results: From 18 eligible randomized clinical trials that included 9108 critically ill adults with sepsis or septic shock (median age, 54 years; IQR, 48-57; 5961 men [65%]), 17 trials (9014 participants) contributed data to the primary outcome. The pooled estimated risk ratio for all-cause 90-day mortality for prolonged infusions of ß-lactam antibiotics compared with intermittent infusions was 0.86 (95% credible interval, 0.72-0.98; I2 = 21.5%; high certainty), with a 99.1% posterior probability that prolonged infusions were associated with lower 90-day mortality. Prolonged infusion of ß-lactam antibiotics was associated with a reduced risk of intensive care unit mortality (risk ratio, 0.84; 95% credible interval, 0.70-0.97; high certainty) and an increase in clinical cure (risk ratio, 1.16; 95% credible interval, 1.07-1.31; moderate certainty). Conclusions and Relevance: Among adults in the intensive care unit who had sepsis or septic shock, the use of prolonged ß-lactam antibiotic infusions was associated with a reduced risk of 90-day mortality compared with intermittent infusions. The current evidence presents a high degree of certainty for clinicians to consider prolonged infusions as a standard of care in the management of sepsis and septic shock. Trial Registration: PROSPERO Identifier: CRD42023399434.

Evaluation on the efficacy of processed hydrated and dehydrated amnion chorion membrane on the proliferation of periodontal ligament fibroblasts.

The purpose of the present study was to process and assess the effect of hydrated amnion chorion membrane and dehydrated amnion chorion membrane on proliferation of periodontal ligament (PDL) fibroblast cells. The amnion chorion membrane (ACM) from placenta of 18 systemically healthy patients was obtained from the Department of Obstetrics and Gynaecology. They were processed as hydrated and dehydrated based on different processing methods. The Periodontal ligament cells were obtained from periodontal ligament of freshly extracted premolars of systemically healthy patients, due to orthodontic reasons. The PDL cells were further cultured in laboratory and were exposed to hydrated and dehydrated amnion chorion membrane. The MTT assay was performed to assess the proliferation of PDL fibroblast cells after 24 and 48 h. The hydrated and dehydrated amnion chorion membrane showed proliferation of PDL fibroblasts after 24 and 48 h. The proliferation of PDL fibroblasts in hydrated (p = 0.043) and dehydrated (p = 0.050) amnion chorion membrane was statistically significant at the end of 24 and 48 h respectively. On inter-group comparison dehydrated ACM showed significant proliferation of PDL fibroblasts after 24 (p=0.014) and 48 h (p=0.019). Within the limits of the present study, it can be concluded: both hydrated and dehydrated amnion chorion membrane showed proliferationof PDL fibroblast cells. However, dehydrated ACM showed significant proliferation of PDL fibroblasts.

Prevalence and associated factors of cerebral microbleeds in a rural population of the United States.

OBJECTIVE: Cerebral microbleeds (CMBs) can carry an advanced risk for the development and burden of cerebrovascular and cognitive disorders. Large-scale population-based studies are required to identify the at-risk population. METHOD: Ten percent (N = 3,056) of the Geisinger DiscovEHR Initiative Cohort participants who had brain magnetic resonance imaging (MRI) for any indication were randomly selected. Patients with CMBs were compared to an age-, gender-, body mass index-, and hypertension-matched cohort of patients without CMB. The prevalence of comorbidities and use of anticoagulation therapy was investigated in association with CMB presence (binary logistic regression), quantity (ordinal regression), and topography (multinomial regression). RESULTS: Among 3,056 selected participants, 477 (15.6 %) had CMBs in their MRI. Patients with CMBs were older and were more prevalently hypertensive, with ischemic stroke, arrhythmia, dyslipidemia, coronary artery disease, and the use of warfarin. After propensity-score matching, 477 patients with CMBs and 974 without were included for further analyses. Predictors of ≥5 CMBs were ischemic stroke (OR, 1.6; 95 % CI, 1.2 -2.0), peripheral vascular disease (OR, 1.6; 95 % CI, 1.1-2.3), and thrombocytopenia (OR, 1.9; 95 % CI, 1.2-2.9). Ischemic stroke was associated with strictly lobar CMBs more strongly than deep/infra-tentorial CMBs (OR, 2.1; 95 % CI, 1.5-3.1; vs. OR, 1.4; CI, 1.1-1.8). CONCLUSIONS: CMBs were prevalent in our white population. Old age, hypertension, anticoagulant treatment, thrombocytopenia, and a history of vascular diseases including stroke, were associated with CMBs.

Association of insertion /deletion polymorphism of ace gene with essential hypertension in patients of Khyber Pakhtunkhwa.

Objective &Background: The exact cause of hypertension is unknown in about 90 to 95% patients, known as essential hypertension. Genes may play a crucial role in the pathology of essential hypertension. Gene for angiotensin converting enzyme (ACE) is found on long arm of chromosome 17q23, where 287 base pair insertion or deletion (I/D) polymorphism may occur. This study was aimed to assess the association of I/D polymorphism of ACE gene with blood pressure (BP) in Patients of Khyber Pakhtunkhwa (KPK). Methods: This Descriptive Cross-sectional study was conducted from 1st June 2021 to 30th September 2021 at Kuwait Teaching Hospital, Peshawar. The genomic DNA was extracted from lymphocytes and PCR was performed for identification of ACE I/D polymorphism. Results: Total 181 individuals (121 Hypertensive and 60 normal) were enrolled in the study. The measured systolic and diastolic BP in cases were 153.91mmHg±12.65 and 92.94mmHg±5.72, respectively while in control were 118.20±17.13 and 74.12mmHg±7.58, respectively. The Deletion Homozygous (DD), Insertion Homozygous (II) and Deletion and Insertion Heterozygous (DI) genotypes in hypertensive patients were 47 (38.84%), 17 (14.04%) and 57 (47.10%) respectively while in Control group the DD, II and DI were 4 (6.66%), 25 (41.66%) and 31 (51.66%) respectively. This study showed association of DD genotypes of the ACE gene with hypertension as compared to healthy individuals. Conclusion: Individuals with DD genotype may have association with hypertension. polymorphism of ACE gene was proved to be an important genetic marker for essential hypertension in Patients of KPK.

High Burden of Intestinal Colonization With Antimicrobial-Resistant Bacteria in Chile: An Antibiotic Resistance in Communities and Hospitals (ARCH) Study.

BACKGROUND: Antimicrobial resistance is a global threat, heavily impacting low- and middle-income countries. This study estimated antimicrobial-resistant gram-negative bacteria (GNB) fecal colonization prevalence in hospitalized and community-dwelling adults in Chile before the coronavirus disease 2019 pandemic. METHODS: From December 2018 to May 2019, we enrolled hospitalized adults in 4 public hospitals and community dwellers from central Chile, who provided fecal specimens and epidemiological information. Samples were plated onto MacConkey agar with ciprofloxacin or ceftazidime added. All recovered morphotypes were identified and characterized according to the following phenotypes: fluoroquinolone-resistant (FQR), extended-spectrum cephalosporin-resistant (ESCR), carbapenem-resistant (CR), or multidrug-resistant (MDR; as per Centers for Disease Control and Prevention criteria) GNB. Categories were not mutually exclusive. RESULTS: A total of 775 hospitalized adults and 357 community dwellers were enrolled. Among hospitalized subjects, the prevalence of colonization with FQR, ESCR, CR, or MDR-GNB was 46.4% (95% confidence interval [CI], 42.9-50.0), 41.2% (95% CI, 37.7-44.6), 14.5% (95% CI, 12.0-16.9), and 26.3% (95% CI, 23.2-29.4). In the community, the prevalence of FQR, ESCR, CR, and MDR-GNB colonization was 39.5% (95% CI, 34.4-44.6), 28.9% (95% CI, 24.2-33.6), 5.6% (95% CI, 3.2-8.0), and 4.8% (95% CI, 2.6-7.0), respectively. CONCLUSIONS: A high burden of antimicrobial-resistant GNB colonization was observed in this sample of hospitalized and community-dwelling adults, suggesting that the community is a relevant source of antibiotic resistance. Efforts are needed to understand the relatedness between resistant strains circulating in the community and hospitals.

Comprehensive phenotypic and functional analysis of dominant and recessive FOXE3 alleles in ocular developmental disorders.

The forkhead transcription factor FOXE3 is critical for vertebrate eye development. Recessive and dominant variants cause human ocular disease but the full range of phenotypes and mechanisms of action for the two classes of variants are unknown. We identified FOXE3 variants in individuals with congenital eye malformations and carried out in vitro functional analysis on selected alleles. Sixteen new recessive and dominant families, including six novel variants, were identified. Analysis of new and previously reported genetic and clinical data demonstrated a broad phenotypic range with an overlap between recessive and dominant disease. Most families with recessive alleles, composed of truncating and forkhead-domain missense variants, had severe corneal opacity (90%; sclerocornea in 47%), aphakia (83%) and microphthalmia (80%), but some had milder features including isolated cataract. The phenotype was most variable for recessive missense variants, suggesting that the functional consequences may be highly dependent on the type of amino acid substitution and its position. When assessed, aniridia or iris hypoplasia were noted in 89% and optic nerve anomalies in 60% of recessive cases, indicating that these defects are also common and may be underrecognized. In dominant pedigrees, caused by extension variants, normal eye size (96%), cataracts (99%) and variable anterior segment anomalies were seen in most, but some individuals had microphthalmia, aphakia or sclerocornea, more typical of recessive disease. Functional studies identified variable effects on the protein stability, DNA binding, nuclear localization and transcriptional activity for recessive FOXE3 variants, whereas dominant alleles showed severe impairment in all areas and dominant-negative characteristics.

Evaluation of the Performance of Manual Antimicrobial Susceptibility Testing Methods and Disk Breakpoints for Stenotrophomonas maltophilia.

Stenotrophomonas maltophilia are an emerging cause of serious infections with high associated mortality in immunocompromised patients. Treatment of S. maltophilia infections is complicated by intrinsic resistance to many antimicrobials, including carbapenems, aminoglycosides, and some cephalosporins. Despite this, >90% of isolates are susceptible to trimethoprim-sulfamethoxazole (SXT), which is front-line therapy for this organism. Side-effects of SXT include bone marrow suppression, which precludes its use for many neutropenic patients. In this population, levofloxacin (LEV), minocycline (MIN), ceftazidime (CAZ), ciprofloxacin (CIP) and tigecycline (TIG) are used as alternative therapies - all of which require testing to inform susceptibilities. The reference standard method for testing S. maltophilia is broth microdilution (BMD), but very few clinical laboratories perform reference BMD. Furthermore, interpretive criteria are not available for CIP or TIG for S. maltophilia, although generic pharmacokinetic/pharmacodynamic (PK/PD) MIC breakpoints are available for these drugs. We assessed performance of disk and gradient diffusion tests relative to BMD for 109 contemporary isolates of S. maltophilia Categorical agreement for SXT, LEV and MIN disk diffusion was 93%, 89%, and 95%, respectively. Categorical agreement for SXT, LEV, MIN and CAZ gradient strips was 98%, 85%, 93%, 71%, respectively by Etest (bioMerieux), and 98%, 83%, 99%, and 73%, by MTS (Liofilchem). CIP and TGC, two clinically valuable alternatives to SXT, did not demonstrate promising disk to MIC correlates using CLSI M100 P. aeruginosa or PK/PD breakpoints. Manual commercial tests perform well for S. maltophilia, with the exception of tests for LEV and CAZ, where high error rates were observed.

High-level ceftazidime/avibactam resistance in Escherichia coli conferred by the novel plasmid-mediated ß-lactamase CMY-185 variant.

OBJECTIVES: To characterize a blaCMY variant associated with ceftazidime/avibactam resistance from a serially collected Escherichia coli isolate. METHODS: A patient with an intra-abdominal infection due to recurrent E. coli was treated with ceftazidime/avibactam. On Day 48 of ceftazidime/avibactam therapy, E. coli with a ceftazidime/avibactam MIC of >256 mg/L was identified from abdominal drainage. Illumina and Oxford Nanopore Technologies WGS was performed on serial isolates to identify potential resistance mechanisms. Site-directed mutants of CMY ß-lactamase were constructed to identify amino acid residues responsible for ceftazidime/avibactam resistance. RESULTS: WGS revealed that all three isolates were E. coli ST410. The ceftazidime/avibactam-resistant strain uniquely acquired a novel CMY ß-lactamase gene, herein called blaCMY-185, harboured on an IncI-γ/K1 conjugative plasmid. The CMY-185 enzyme possessed four amino acid substitutions relative to CMY-2, including A114E, Q120K, V211S and N346Y, and conferred high-level ceftazidime/avibactam resistance with an MIC of 32 mg/L. Single CMY-2 mutants did not confer reduced ceftazidime/avibactam susceptibility. However, double and triple mutants containing N346Y previously associated with ceftazidime/avibactam resistance in other AmpC enzymes, conferred ceftazidime/avibactam MICs ranging between 4 and 32 mg/L as well as reduced susceptibility to the newly developed cephalosporin, cefiderocol. Molecular modelling suggested that the N346Y substitution confers the reduction of avibactam inhibition due to steric hindrance between the side chain of Y346 and the sulphate group of avibactam. CONCLUSIONS: We identified ceftazidime/avibactam resistance in E. coli associated with a novel CMY variant. Unlike other AmpC enzymes, CMY-185 appears to require an additional substitution on top of N346Y to confer ceftazidime/avibactam resistance.

Mass Spectrometry based identification of site-specific proteomic alterations and potential pathways underlying the pathophysiology of schizophrenia.

BACKGROUND: Schizophrenia (SZ) is a complex multifactorial disorder that affects 1% of the population worldwide with no available effective treatment. Although proteomic alterations are reported in SZ however proteomic expression aberrations among different brain regions are not fully determined. Therefore, the present study aimed spatial differential protein expression profiling of three distinct regions of SZ brain and identification of associated affected biological pathways in SZ progression. METHODS AND RESULTS: Comparative protein expression profiling of three distinct autopsied human brain regions (i.e., substantia nigra, hippocampus and prefrontal cortex) of SZ was performed with respective healthy controls. Using two-dimensional electrophoresis (2DE)-based nano liquid chromatography tandem mass spectrometry (Nano-LC MS /MS) analysis, 1443 proteins were identified out of which 58 connote to be significantly dysregulated, representing 26 of substantia nigra,14 of hippocampus and 18 of prefrontal cortex. The 58 differentially expressed proteins were further analyzed using Ingenuity pathway analysis (IPA). The IPA analysis provided protein-protein interaction networks of several proteins including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kb), extracellular signal regulated kinases 1/2 (ERK1/2), alpha serine / Threonine-protein kinase (AKT1), cellular tumor antigen p53 (TP53) and amyloid precursor protein (APP), holding prime positions in networks and interacts with most of the identified proteins and their closely interacting partners. CONCLUSION: These findings provide conceptual insights of novel SZ related pathways and the cross talk of co and contra regulated proteins. This spatial proteomic analysis will further broaden the conceptual framework for schizophrenia research in future.

Pediatric Acute Respiratory Distress Syndrome in South African PICUs: A Multisite Point-Prevalence Study.

OBJECTIVES: To describe the prevalence of pediatric acute respiratory distress syndrome (pARDS) and the characteristics of children with pARDS in South African PICUs. DESIGN: Observational multicenter, cross-sectional point-prevalence study. SETTING: Eight PICUs in four South African provinces. PATIENTS: All children beyond the neonatal period and under 18 years of age admitted to participating PICUs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Clinical and demographic data were prospectively collected on a single day of each month, from February to July 2022, using a centralized database. Cases with or at risk of pARDS were identified using the 2015 Pediatric Acute Lung Injury Consensus Conference criteria. Prevalence was calculated as the number of children meeting pARDS criteria/the total number of children admitted to PICU at the same time points. Three hundred ten patients were present in the PICU on study days: 166 (53.5%) male, median (interquartile range [IQR]) age 9.8 (3.1-32.9) months, and 195 (62.9%) invasively mechanically ventilated. Seventy-one (22.9%) patients were classified as being "at risk" of pARDS and 95 patients (prevalence 30.6%; 95% CI, 24.7-37.5%) fulfilled pARDS case criteria, with severity classified as mild (58.2%), moderate (25.3%), and severe (17.6%). Median (IQR) admission Pediatric Index of Mortality 3 risk of mortality in patients with and without pARDS was 5.6 (3.4-12.1) % versus 3.9 (1.0-8.2) % ( p = 0.002). Diagnostic categories differed between pARDS and non-pARDS groups ( p = 0.002), with no difference in age, sex, or presence of comorbidities. On multivariable logistic regression, increasing admission risk of mortality (adjusted odds ratio [aOR] 1.02; 95% CI, 1.00-1.04; p = 0.04) and being admitted with a respiratory condition (aOR 2.64; 95% CI, 1.27-5.48; p = 0.01) were independently associated with an increased likelihood of having pARDS. CONCLUSIONS: The 30.6% prevalence of pARDS in South Africa is substantially higher than reports from other sociogeographical regions, highlighting the need for further research in this setting.

Electronic nose as a tool for early detection of diseases and quality monitoring in fresh postharvest produce: A comprehensive review.

Postharvest diseases and quality degradation are the major factors causing food losses in the fresh produce supply chain. Hence, detecting diseases and quality deterioration at the asymptomatic stage of produce enables growers to treat the diseases earlier, maintain quality and reduce postharvest food losses. With the emergence of numerous technologies to detect diseases early and monitor the quality of fresh produce, such as polymerase chain reaction, gas chromatography-mass spectrophotometry, and near-infrared spectroscopy, electronic nose (EN) has also gained acknowledgement and popularity in the past decade as a robust and non-invasive analysis tool to detect odor profile and establish volatile biomarkers for metabolomics databases. However, literature reviewing the EN research on the early detection of diseases in produce after harvest is scarce. The fundamental concept of EN working principles (odor sampling, gas detection, and data acquisition method), as well as the application of EN as a whole, are covered in the first section of the review. An in-depth discussion of the application of EN analysis in the early identification of postharvest diseases and quality monitoring is provided in the subsequent sections, which is the key objective of this comprehensive review. The prospect, limitations, and likely future developments of EN in the postharvest sector are further highlighted in the last section.

Neuropharmacological evaluation of different species of Curcubitaceae seeds extract in experimental animals.

Major depressive disorders such as anxiety and depression is predominantly developed in the modern era due to stressful lifestyle and now become the second leading cause of disability. The purpose of the current investigation to evaluate and compared the neuropharmacological effects of three different varaities of Cucurbitaceae seeds including Cucumis Melo var. flexuosus, Cucumis melo var. reticulatus and Santa claus melons ethanol seed extract in experimental animals at three different doses, i.e. 25, 50 and 100mg/kg in animals after 60 days of oral administration. Afterward, various neuropharphamcological activities such as general behavior, phenobarbitone induced sleeping time and exploratory behavior (Elevated plus-maze and head dip test) and motor coordination by Rotarod test were assessed and compared with the control group. The extracts producing dose depended effects on central nervous system. The general behavior profile revealed significant depression at maximum doses. At maximum dose 100mg/kg of Cucumis reticulatus and Santa Claus, seed extracts significantly increases the number of entries in open arms. On the other hand, the Cucumis flexuosus seed extract significantly increases the frequency of numbers of head dips in mice. However, the lower doses of the extracts showed less significant results. The results suggested that all extracts at maximum doses produces anxiolytic effects without affecting the motor coordination in animals.