-
Nature Communications Jun 2024IncX3 plasmids carrying the New Delhi metallo-β-lactamase-encoding gene, bla, are rapidly spreading globally in both humans and animals. Given that carbapenems are...
IncX3 plasmids carrying the New Delhi metallo-β-lactamase-encoding gene, bla, are rapidly spreading globally in both humans and animals. Given that carbapenems are listed on the WHO AWaRe watch group and are prohibited for use in animals, the drivers for the successful dissemination of Carbapenem-Resistant Enterobacterales (CRE) carrying bla-IncX3 plasmids still remain unknown. We observe that E. coli carrying bla-IncX3 can persist in chicken intestines either under the administration of amoxicillin, one of the largest veterinary β-lactams used in livestock, or without any antibiotic pressure. We therefore characterise the bla-IncX3 plasmid and identify a transcription regulator, VirBR, that binds to the promoter of the regulator gene actX enhancing the transcription of Type IV secretion systems (T4SS); thereby, promoting conjugation of IncX3 plasmids, increasing pili adhesion capacity and enhancing the colonisation of bla-IncX3 transconjugants in animal digestive tracts. Our mechanistic and in-vivo studies identify VirBR as a major factor in the successful spread of bla-IncX3 across one-health AMR sectors. Furthermore, VirBR enhances the plasmid conjugation and T4SS expression by the presence of copper and zinc ions, thereby having profound ramifications on the use of universal animal feeds.
Topics: Animals; Plasmids; beta-Lactamases; Chickens; Humans; Escherichia coli; Anti-Bacterial Agents; Conjugation, Genetic; Escherichia coli Proteins; Type IV Secretion Systems; Transcription Factors; Amoxicillin; Promoter Regions, Genetic; Escherichia coli Infections; Gene Expression Regulation, Bacterial; Intestines
PubMed: 38944647
DOI: 10.1038/s41467-024-49800-1 -
NPJ Biofilms and Microbiomes Jun 2024Gut metaproteomics can provide direct evidence of microbial functions actively expressed in the colonic environments, contributing to clarify the role of the gut... (Meta-Analysis)
Meta-Analysis
Gut metaproteomics can provide direct evidence of microbial functions actively expressed in the colonic environments, contributing to clarify the role of the gut microbiota in human physiology. In this study, we re-analyzed 10 fecal metaproteomics datasets of healthy individuals from different continents and countries, with the aim of identifying stable and variable gut microbial functions and defining the contribution of specific bacterial taxa to the main metabolic pathways. The "core" metaproteome included 182 microbial functions and 83 pathways that were identified in all individuals analyzed. Several enzymes involved in glucose and pyruvate metabolism, along with glutamate dehydrogenase, acetate kinase, elongation factors G and Tu and DnaK, were the proteins with the lowest abundance variability in the cohorts under study. On the contrary, proteins involved in chemotaxis, response to stress and cell adhesion were among the most variable functions. Random-effect meta-analysis of correlation trends between taxa, functions and pathways revealed key ecological and molecular associations within the gut microbiota. The contribution of specific bacterial taxa to the main biological processes was also investigated, finding that Faecalibacterium is the most stable genus and the top contributor to anti-inflammatory butyrate production in the healthy gut microbiota. Active production of other mucosal immunomodulators facilitating host tolerance was observed, including Roseburia flagellin and lipopolysaccharide biosynthetic enzymes expressed by members of Bacteroidota. Our study provides a detailed picture of the healthy human gut microbiota, contributing to unveil its functional mechanisms and its relationship with nutrition, immunity, and environmental stressors.
Topics: Humans; Gastrointestinal Microbiome; Proteomics; Bacteria; Feces; Bacterial Proteins; Healthy Volunteers; Proteome; Metabolic Networks and Pathways
PubMed: 38944645
DOI: 10.1038/s41522-024-00526-4 -
Cancer Science Jun 2024Recent studies have shown that transmembrane-type tight junction proteins are upregulated in various cancers compared with their levels in normal tissues and are...
Recent studies have shown that transmembrane-type tight junction proteins are upregulated in various cancers compared with their levels in normal tissues and are involved in cancer progression, suggesting that they are potential therapeutic targets. Here, we demonstrated the expression profile and a novel role of junctional adhesion molecule-A (JAM-A) in breast cancer. Immunohistochemistry of surgical specimens showed that JAM-A was highly expressed from carcinoma in situ lesions, as in other adenocarcinomas, with higher expression in invasive carcinomas. High expression of JAM-A contributed to malignant aspects such as lymph node metastasis and lymphatic involvement positivity. In breast cancer cells, JAM-A expression status affects malignant potentials including proliferation and migration. Multilayered proteomics revealed that JAM-A interacts with the amino acid transporter LAT1 in breast cancer cells. JAM-A regulates the expression of LAT1 and interacts with it on the whole cell membrane, leading to enhanced amino acid uptake to promote tumor growth. Double high expression of JAM-A and LAT1 predicts poor prognosis in patients with breast cancer. Of note, an antibody against an extracellular domain of JAM-A suppressed the proliferation of breast cancer cells. Our findings indicate the possibility of JAM-A-targeted therapy ideally combined with LAT1-targeted therapy as a new therapeutic strategy against breast cancer.
PubMed: 38943512
DOI: 10.1111/cas.16259 -
Alzheimer's Research & Therapy Jun 2024Amyloid-β (Aβ) and tau are brain hallmarks of Alzheimer's disease (AD), also present in blood as soluble biomarkers or encapsulated in extracellular vesicles (EVs).... (Comparative Study)
Comparative Study
BACKGROUND
Amyloid-β (Aβ) and tau are brain hallmarks of Alzheimer's disease (AD), also present in blood as soluble biomarkers or encapsulated in extracellular vesicles (EVs). Our goal was to assess how soluble plasma biomarkers of AD pathology correlate with the number and content of EVs.
METHODS
Single-molecule enzyme-linked assays were used to quantify Aβ42/40 and tau in plasma samples and neurally-derived EVs (NDEVs) from a cohort of APOE ε4- (n = 168) and APOE ε4+ (n = 68) cognitively normal individuals and AD patients (n = 55). The ratio of CD56 (Neuronal cell-adhesion molecule) to CD81 signal measured by ELISA-DELFIA was used for the relative quantification of NDEVs in plasma samples.
RESULTS
The soluble plasma Aβ42/40 ratio is decreased in AD patients compared to cognitively normal individuals. The amount and content (Aβ40, Aβ42, tau) of plasma NDEVs were similar between groups. Plasma NDEVs quantity remain consistent with aging and between AD and CN individuals. However, the quantity of soluble biomarkers was negatively correlated to NDEVs number in cognitively normal individuals, while in AD patients, this correlation is lost, suggesting a shift in the mechanism underpinning the production and the release of these biomarkers in pathological conditions.
CONCLUSION
Soluble plasma Aβ42/40 ratio is the most robust biomarker to discriminate between AD patients and CN individuals, as it normalizes for the number of NDEVs. Analysis of NDEVs and their content pointed toward peculiar mechanisms of Aβ release in AD. Further research on independent cohorts can confirm our findings and assess whether plasma Aβ and tau need correction by NDEVs for better AD risk identification in CN populations.
Topics: Humans; Alzheimer Disease; Extracellular Vesicles; Biomarkers; Female; Male; Amyloid beta-Peptides; Aged; tau Proteins; Peptide Fragments; Aged, 80 and over; Middle Aged; Cohort Studies; Apolipoprotein E4
PubMed: 38943196
DOI: 10.1186/s13195-024-01508-6 -
BMC Genomics Jun 2024Ménière's disease (MD) is a disorder of the inner ear that causes episodic bouts of severe dizziness, roaring tinnitus, and fluctuating hearing loss. To date, no...
BACKGROUND
Ménière's disease (MD) is a disorder of the inner ear that causes episodic bouts of severe dizziness, roaring tinnitus, and fluctuating hearing loss. To date, no targeted therapy exists. As such, we have undertaken a large whole genome sequencing study on carefully phenotyped unilateral MD patients with the goal of gene/pathway discovery and a move towards targeted intervention. This study was a retrospective review of patients with a history of Ménière's disease. Genomic DNA, acquired from saliva samples, was purified and subjected to whole genome sequencing.
RESULTS
Stringent variant calling, performed on 511 samples passing quality checks, followed by gene-based filtering by recurrence and proximity in molecular interaction networks, led to 481 high priority MD genes. These high priority genes, including MPHOSPH8, MYO18A, TRIOBP, OTOGL, TNC, and MYO6, were previously implicated in hearing loss, balance, and cochlear function, and were significantly enriched in common variant studies of hearing loss. Validation in an independent MD cohort confirmed 82 recurrent genes. Pathway analysis pointed to cell-cell adhesion, extracellular matrix, and cellular energy maintenance as key mediators of MD. Furthermore, the MD-prioritized genes were highly expressed in human inner ear hair cells and dark/vestibular cells, and were differentially expressed in a mouse model of hearing loss.
CONCLUSION
By enabling the development of model systems that may lead to targeted therapies and MD screening panels, the genes and variants identified in this study will inform diagnosis and treatment of MD.
Topics: Meniere Disease; Humans; Endolymphatic Hydrops; Animals; Mice; Genomics; Male; Female; Retrospective Studies; Whole Genome Sequencing; Middle Aged; Adult
PubMed: 38943082
DOI: 10.1186/s12864-024-10552-3 -
Nature Communications Jun 2024Dexamethasone is the standard of care for critically ill patients with COVID-19, but the mechanisms by which it decreases mortality and its immunological effects in this...
Dexamethasone is the standard of care for critically ill patients with COVID-19, but the mechanisms by which it decreases mortality and its immunological effects in this setting are not understood. Here we perform bulk and single-cell RNA sequencing of samples from the lower respiratory tract and blood, and assess plasma cytokine profiling to study the effects of dexamethasone on both systemic and pulmonary immune cell compartments. In blood samples, dexamethasone is associated with decreased expression of genes associated with T cell activation, including TNFSFR4 and IL21R. We also identify decreased expression of several immune pathways, including major histocompatibility complex-II signaling, selectin P ligand signaling, and T cell recruitment by intercellular adhesion molecule and integrin activation, suggesting these are potential mechanisms of the therapeutic benefit of steroids in COVID-19. We identify additional compartment- and cell- specific differences in the effect of dexamethasone that are reproducible in publicly available datasets, including steroid-resistant interferon pathway expression in the respiratory tract, which may be additional therapeutic targets. In summary, we demonstrate compartment-specific effects of dexamethasone in critically ill COVID-19 patients, providing mechanistic insights with potential therapeutic relevance. Our results highlight the importance of studying compartmentalized inflammation in critically ill patients.
Topics: Dexamethasone; Humans; COVID-19 Drug Treatment; COVID-19; SARS-CoV-2; Lung; Cytokines; Critical Illness; Male; Single-Cell Analysis; Female; Middle Aged; T-Lymphocytes; Aged; Lymphocyte Activation
PubMed: 38942804
DOI: 10.1038/s41467-024-49756-2 -
Scientific Reports Jun 2024Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's Disease, a chronic granulomatous enteritis of ruminants. MAP establishes an...
Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's Disease, a chronic granulomatous enteritis of ruminants. MAP establishes an infection in the host via the small intestine. This requires the bacterium to adhere to, and be internalised by, cells of the intestinal tract. The effector molecules expressed by MAP for this purpose remain to be fully identified and understood. Mammalian cell entry (mce) proteins have been shown to enable other Mycobacterial species to attach to and invade host epithelial cells. Here, we have expressed Mce1A, Mce1D, Mce3C and Mce4A proteins derived from MAP on the surface of a non-invasive Escherichia coli to characterise their role in the initial interaction between MAP and the host. To this end, expression of mce1A was found to significantly increase the ability of the E. coli to attach and survive intracellularly in human monocyte-like THP-1 cells, whereas expression of mce1D was found to significantly increase attachment and invasion of E. coli to bovine epithelial cell-like MDBK cells, implying cell-type specificity. Furthermore, expression of Mce1A and Mce1D on the surface of a previously non-invasive E. coli enhanced the ability of the bacterium to infect 3D bovine basal-out enteroids. Together, our data contributes to our understanding of the effector molecules utilised by MAP in the initial interaction with the host, and may provide potential targets for therapeutic intervention.
Topics: Mycobacterium avium subsp. paratuberculosis; Paratuberculosis; Animals; Humans; Cattle; Bacterial Proteins; Bacterial Adhesion; Epithelial Cells; Escherichia coli; Cell Line; THP-1 Cells
PubMed: 38942800
DOI: 10.1038/s41598-024-65592-2 -
Microbial Pathogenesis Jun 2024Campylobacter jejuni is one of the major causes of bacterial gastrointestinal disease in humans worldwide. This foodborne pathogen colonizes the intestinal tracts of...
Campylobacter jejuni is one of the major causes of bacterial gastrointestinal disease in humans worldwide. This foodborne pathogen colonizes the intestinal tracts of chickens, and consumption of chicken and poultry products is identified as a common route of transmission. We analyzed two C. jejuni strains after oral challenge with 10 CFU/ml of C. jejuni per chick; one strain was a robust colonizer (A74/C) and the other a poor colonizer (A74/O). We also found extensive phenotypic differences in growth rate, biofilm production, and in vitro adherence, invasion, intracellular survival, and transcytosis. Strains A74/C and A74/O were genotypically similar with respect to their whole genome alignment, core genome, and ribosomal MLST, MLST, flaA, porA, and PFGE typing. The global proteomes of the two congenic strains were quantitatively analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and 618 and 453 proteins were identified from A74/C and A74/O isolates, respectively. Cluster of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that carbon metabolism and motility proteins were distinctively overexpressed in strain A74/C. The robust colonizer also exhibited a unique proteome profile characterized by significantly increased expression of proteins linked to adhesion, invasion, chemotaxis, energy, protein synthesis, heat shock proteins, iron regulation, two-component regulatory systems, and multidrug efflux pump. Our study underlines phenotypic, genotypic, and proteomic variations of the poor and robust colonizing C. jejuni strains, suggesting that several factors may contribute to mediating the different colonization potentials of the isogenic isolates.
PubMed: 38942248
DOI: 10.1016/j.micpath.2024.106766 -
Journal of Minimally Invasive Gynecology Jun 2024To estimate the risk of bowel obstruction after hysterectomy for benign indications depending on the surgical method (abdominal, vaginal, or laparoscopic) and identify...
STUDY OBJECTIVE
To estimate the risk of bowel obstruction after hysterectomy for benign indications depending on the surgical method (abdominal, vaginal, or laparoscopic) and identify risk factors for adhesive bowel obstruction.
DESIGN
A national registry-based cohort.
SETTING
Danish hospitals during the period 1984-2013.
PATIENTS
Danish women who underwent hysterectomy for benign indications (N=125,568).
INTERVENTIONS
Abdominal hysterectomies were compared with vaginal hysterectomies, laparoscopic hysterectomies, and minimally invasive (vaginal and laparoscopic) hysterectomies.
MEASUREMENTS AND MAIN RESULTS
The incidence of bowel obstruction according to the surgical method was compared using Cox proportional hazard regression. The covariates included were the time period, age, concomitant operations, prior abdominal surgery or disease, and socioeconomic factors. In a sub-analysis (n=35,712 women) of the period 2004-2013, detailed information from the Danish Hysterectomy Database enabled the inclusion of patient-related, surgery-related, and complication-related covariates. The overall crude incidence of bowel obstruction was 17.4/1000 hysterectomies (2196 incident cases). The 10-year cumulative incidence of bowel obstruction differed between the surgical routes (abdominal, 1.7%; laparoscopic, 1.4%; and vaginal, 0.9%). In multiple adjusted analyses, the risk of bowel obstruction was higher after abdominal hysterectomy than after vaginal (HR 1.64 [95% CI 1.39-1.93]) and minimally invasive (vaginal or laparoscopic) hysterectomy (HR 1.54 [1.33-1.79]). Additional pre-existing risk factors for bowel obstruction at the time of hysterectomy were increased age, low education, low income, smoking, high ASA comorbidity score, history of infertility, abdominal infection, and prior abdominal surgery (apart from cesarean section),penetrating lesions in abdominal organs, or operative adhesiolysis. Perioperative risk factors at the time of hysterectomy included concomitant removal of the ovaries, adhesiolysis, blood transfusion, readmission, and overall presence of perioperative complications.
CONCLUSION
Abdominal hysterectomy is associated with a 54% higher risk of bowel obstruction than minimally invasive (laparoscopic or vaginal) hysterectomy.
PubMed: 38942232
DOI: 10.1016/j.jmig.2024.06.010 -
European Journal of Dentistry Jun 2024The proper closure of the access cavity between appointments during endodontic treatment is paramount and relies on temporary fillings. This systematic review evaluates...
The proper closure of the access cavity between appointments during endodontic treatment is paramount and relies on temporary fillings. This systematic review evaluates the effectiveness of zinc oxide-based materials and glass-ionomer cement (GIC) as temporary coronal sealers after root canal treatment in extracted human teeth. Three databases were searched to identify randomized clinical trials that examined the sealing properties of various temporary sealing materials using dyes or stains as indicators. A total of seven studies that fulfilled the eligibility criteria were critically analyzed. These indicated significant variations in the relative sealing ability of the coronal breach of endodontically treated teeth, either by zinc oxide or GIC-based materials. While GIC-based material (e.g., Fuji IX and Fuji II) exhibited superior sealing of single-rooted teeth, zinc oxide-based material (e.g., Cavit, Coltosol, Caviton) also showed promising attributes. Resin-modified GIC formulations displayed enhanced physical properties, yet challenges related to adhesive failure and shrinkage during polymerization were observed. Zinc oxide-based materials have demonstrated superior coronal sealing effectiveness over certain GIC in controlled settings. Their premixed nature ensures consistent application and hygroscopic properties improve cavity sealing. However, the focus on dye penetration tests for microleakage may not fully represent the risk of bacterial infiltration. Thus, studies are crucial for validating these findings in clinical contexts.
PubMed: 38942056
DOI: 10.1055/s-0044-1782695