Metagenomic Investigation of the Short-Term Temporal and Spatial Dynamics of the Bacterial Microbiome and the Resistome Downstream of a Wastewater Treatment Plant in the Iskar River in Bulgaria.

Waste Water Treatment Plants (WWTP) aim to reduce contamination in effluent water; however, studies indicate antimicrobial resistance genes (ARGs) persist post-treatment, potentially leading to their spread from human populated areas into the environment. This study evaluated the impact of a large WWTP serving 125,000 people on the Iskar River in Bulgaria, by characterizing the spatial and short-term temporal dynamics in bacterial community dynamics and resistance profiles of the surface water. Pairs of samples were collected biweekly on four dates from two different locations, one about 800 m after the WWTP effluents and the other 10 km downstream. Taxonomic classification revealed the dominance of Pseudomonodota and Bacteriodota, notably the genera Flavobacterium, Aquirufa, Acidovorax, Polynucleobacter, and Limnohabitans. The taxonomic structure corresponded with both lentic and lotic freshwater habitats, with Flavobacterium exhibiting a significant decrease over the study period. Principal Coordinate Analysis revealed statistically significant differences in bacterial community composition between samples collected on different dates. Differential abundance analysis identified notable enrichment of Polynucleobacter and Limnohabitans. There were shifts within the enriched or depleted bacterial taxa between early and late sampling dates. High relative abundance of the genes erm(B), erm(F), mph(E), msr(E) (macrolides); tet(C), tet(O), tet(W), tet(Q) and tet(X) (tetracyclines); sul1 and sul2 (sulphonamides); and cfxA3, cfxA6 (beta-lactams) were detected, with trends of increased presence in the latest sampling dates and in the location closer to the WWTP. Of note, genes conferring resistance to carbapenems blaOXA-58 and blaIMP-33-like were identified. Co-occurrence analysis of ARGs and mobile genetic elements on putative plasmids showed few instances, and the estimated human health risk score (0.19) according to MetaCompare2.0 was low. In total, 29 metagenome-assembled genomes were recovered, with only a few harbouring ARGs. This study enhances our understanding of freshwater microbial community dynamics and antibiotic resistance profiles, highlighting the need for continued ARGs monitoring.

Permittivity tensor imaging: modular label-free imaging of 3D dry mass and 3D orientation at high resolution.

The dry mass and the orientation of biomolecules can be imaged without a label by measuring their permittivity tensor (PT), which describes how biomolecules affect the phase and polarization of light. Three-dimensional (3D) imaging of PT has been challenging. We present a label-free computational microscopy technique, PT imaging (PTI), for the 3D measurement of PT. PTI encodes the invisible PT into images using oblique illumination, polarization-sensitive detection and volumetric sampling. PT is decoded from the data with a vectorial imaging model and a multi-channel inverse algorithm, assuming uniaxial symmetry in each voxel. We demonstrate high-resolution imaging of PT of isotropic beads, anisotropic glass targets, mouse brain tissue, infected cells and histology slides. PTI outperforms previous label-free imaging techniques such as vector tomography, ptychography and light-field imaging in resolving the 3D orientation and symmetry of organelles, cells and tissue. We provide open-source software and modular hardware to enable the adoption of the method.

On the origin of epitaxial rhombohedral-B4C growth by CVD on 4H-SiC.

Rhombohedral boron carbide, often referred to as r-B4C, is a potential material for applications in optoelectronic and thermoelectric devices. From fundamental thin film growth and characterization, we investigate the film-substrate interface between the r-B4C films grown on 4H-SiC (0001̄) (C-face) and 4H-SiC (0001) (Si-face) during chemical vapor deposition (CVD) to find the origin for epitaxial growth solely observed on the C-face. We used high-resolution (scanning) transmission electron microscopy and electron energy loss spectroscopy to show that there is no surface roughness or additional carbon-based interlayer formation for either substrate. Based on Raman spectroscopy analysis, we also argue that carbon accumulation on the surface hinders the growth of continued epitaxial r-B4C in CVD.

Mussel-Inspired Sonochemical Nanocomposite Coating on Catheters for Prevention of Urinary Infections.

Catheter-associated urinary tract infections are the most common hospital-acquired infections and cause patient discomfort, increased morbidity, and prolonged stays, altogether posing a huge burden on healthcare services. Colonization occurs upon insertion, or later by ascending microbes from the rich periurethral flora, and is therefore virtually unavoidable by medical procedures. Importantly, the dwell time is a significant risk factor for bacteriuria because it gives biofilms time to develop and mature. This is why we engineer antibacterial and antibiofilm coating through ultrasound- and nanoparticle-assisted self-assembly on silicone surfaces and validate it thoroughly in vitro and in vivo. To this end, we combine bimetallic silver/gold nanoparticles, which exercise both biocidal and structural roles, with dopamine-modified gelatin in a facile and substrate-independent sonochemical coating process. The latter mussel-inspired bioadhesive potentiates the activity and durability of the coating while attenuating the intrinsic toxicity of silver. As a result, our approach effectively reduces biofilm formation in a hydrodynamic model of the human bladder and prevents bacteriuria in catheterized rabbits during a week of placement, outperforming conventional silicone catheters. These results substantiate the practical use of nanoparticle-biopolymer composites in combination with ultrasound for the antimicrobial functionalization of indwelling medical devices.

Epidemiological and Genetic Characteristics of Respiratory Viral Coinfections with Different Variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

This study aimed to determine the incidence and etiological, seasonal, and genetic characteristics of respiratory viral coinfections involving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Between October 2020 and January 2024, nasopharyngeal samples were collected from 2277 SARS-CoV-2-positive patients. Two multiplex approaches were used to detect and sequence SARS-CoV-2, influenza A/B viruses, and other seasonal respiratory viruses: multiplex real-time polymerase chain reaction (PCR) and multiplex next-generation sequencing. Coinfections of SARS-CoV-2 with other respiratory viruses were detected in 164 (7.2%) patients. The most common co-infecting virus was respiratory syncytial virus (RSV) (38 cases, 1.7%), followed by bocavirus (BoV) (1.2%) and rhinovirus (RV) (1.1%). Patients ≤ 16 years of age had the highest rate (15%) of mixed infections. Whole-genome sequencing produced 19 complete genomes of seasonal respiratory viral co-pathogens, which were subjected to phylogenetic and amino acid analyses. The detected influenza viruses were classified into the genetic groups 6B.1A.5a.2a and 6B.1A.5a.2a.1 for A(H1N1)pdm09, 3C.2a1b.2a.2a.1 and 3C.2a.2b for A(H3N2), and V1A.3a.2 for the B/Victoria lineage. The RSV-B sequences belonged to the genetic group GB5.0.5a, with HAdV-C belonging to type 1, BoV to genotype VP1, and PIV3 to lineage 1a(i). Multiple amino acid substitutions were identified, including at the antibody-binding sites. This study provides insights into respiratory viral coinfections involving SARS-CoV-2 and reinforces the importance of genetic characterization of co-pathogens in the development of therapeutic and preventive strategies.

Evaluation of cleaved caspase-3 and Ki-67 index on diagnostic biopsy in response to neoadjuvant chemotherapy in the context of post-treatment tumour ypT stage, ypN stage, grade, and molecular subtype.

Introduction: Breast carcinoma is a heterogeneous disease, characterised by diverse clinical behaviour. The aim of this study was to assess how cleaved caspase-3 and Ki-67 index, evaluated on diagnostic biopsy, are related to response to neoadjuvant chemotherapy in the context of molecular subtype, post-treatment tumour, N category, and grade. Material and methods: A retrospective analysis was carried out among 110 breast cancer patients. Ki-67 levels and caspase-3 expression on diagnostic biopsy were explored regarding their relation to tumour grade and molecular subtype, ypT, ypN categories, and T and N categories according to Sataloff tumour response evaluation. Results: A statistically significant relationship was found between Ki-67 levels and tumour grade K-W = 24.2932, p < 0.0001; molecular subtype K-W = 28.5439, p < 0.00000967538; size and invasion of the primary tumour after neoadjuvant chemotherapy K-W = 11.7944, p < 0.0377169; caspase-3 expression after neoadjuvant therapy, evaluated according to the Sataloff classification χ2 = 5.97, df = 1, p = 0.0145. Discussion: No significant difference was found between Ki-67 expression in patients with pathological complete response, compared to those with partial and no response, a statistically significant difference in cases with different molecular subtype, histology grade, and tumour stage after neoadjuvant therapy. Cleaved caspase-3-positive breast cancer cases are often better responders to neoadjuvant therapy, but with no significant correlation to molecular subtype, high-grade categories, or tumour stage. Conclusions: The caspase-3 and Ki-67 index on diagnostic biopsy are related to post-neoadjuvant treatment prognostic factors (ypT stage, grade), proving them useful for prediction of treatment response to neoadjuvant therapy and further patient management.

Genomic Characterization of Carbapenemase-Producing Enterobacter hormaechei, Serratia marcescens, Citrobacter freundii, Providencia stuartii, and Morganella morganii Clinical Isolates from Bulgaria.

Carbapenemase-producing Enterobacter spp. Serratia marcescens, Citrobacter freundii, Providencia spp., and Morganella morganii (CP-ESCPM) are increasingly identified as causative agents of nosocomial infections but are still not under systematic genomic surveillance. In this study, using a combination of whole-genome sequencing and conjugation experiments, we sought to elucidate the genomic characteristics and transferability of resistance genes in clinical CP-ESCPM isolates from Bulgaria. Among the 36 sequenced isolates, NDM-1 (12/36), VIM-4 (11/36), VIM-86 (8/36), and OXA-48 (7/36) carbapenemases were identified; two isolates carried both NDM-1 and VIM-86. The majority of carbapenemase genes were found on self-conjugative plasmids. IncL plasmids were responsible for the spread of OXA-48 among E. hormaechei, C. freundii, and S. marcescens. IncM2 plasmids were generally associated with the spread of NDM-1 in C. freundii and S. marcescens, and also of VIM-4 in C. freundii. IncC plasmids were involved in the spread of the recently described VIM-86 in P. stuartii isolates. IncC plasmids carrying blaNDM-1 and blaVIM-86 were observed too. blaNDM-1 was also detected on IncX3 in S. marcescens and on IncT plasmid in M. morganii. The significant resistance transfer rates we observed highlight the role of the ESCPM group as a reservoir of resistance determinants and stress the need for strengthening infection control measures.

Single-nucleus transcriptomics of epicardial adipose tissue from female pigs reveals effects of exercise training on resident innate and adaptive immune cells.

BACKGROUND: Coronary artery disease (CAD) is a leading cause of death in women. Epicardial adipose tissue (EAT) secretes cytokines to modulate coronary artery function, and the release of fatty acids from EAT serves as a readily available energy source for cardiomyocytes. However, despite having beneficial functions, excessive amounts of EAT can cause the secretion of proinflammatory molecules that increase the instability of atherosclerotic plaques and contribute to CAD progression. Although exercise mitigates CAD, the mechanisms by which exercise impacts EAT are unknown. The Yucatan pig is an excellent translational model for the effects of exercise on cardiac function. Therefore, we sought to determine if chronic aerobic exercise promotes an anti-inflammatory microenvironment in EAT from female Yucatan pigs. METHODS: Sexually mature, female Yucatan pigs (n = 7 total) were assigned to sedentary (Sed, n = 3) or exercise (Ex, n = 4) treatments, and coronary arteries were occluded (O) with an ameroid to mimic CAD or remained non-occluded (N). EAT was collected for bulk (n = 7 total) and single nucleus transcriptomic sequencing (n = 2 total, 1 per exercise treatment). RESULTS: Based on the bulk transcriptomic analysis, exercise upregulated S100 family, G-protein coupled receptor, and CREB signaling in neurons canonical pathways in EAT. The top networks in EAT affected by exercise as measured by bulk RNA sequencing were SRC kinase family, fibroblast growth factor receptor, Jak-Stat, and vascular endothelial growth factor. Single nucleus transcriptomic analysis revealed that exercise increased the interaction between immune, endothelial, and mesenchymal cells in the insulin-like growth factor pathway and between endothelial and other cell types in the platelet endothelial cell adhesion molecule 1 pathway. Sub-clustering revealed nine cell types in EAT, with fibroblast and macrophage populations predominant in O-Ex EAT and T cell populations predominant in N-Ex EAT. Unlike the findings for exercise alone as a treatment, there were not increased interactions between endothelial and mesenchymal cells in O-Ex EAT. Coronary artery occlusion impacted the most genes in T cells and endothelial cells. Genes related to fatty acid metabolism were the most highly upregulated in non-immune cells from O-Ex EAT. Sub-clustering of endothelial cells revealed that N-Ex EAT separated from other treatments. CONCLUSIONS: According to bulk transcriptomics, exercise upregulated pathways and networks related to growth factors and immune cell communication. Based on single nucleus transcriptomics, aerobic exercise increased cell-to-cell interaction amongst immune, mesenchymal, and endothelial cells in female EAT. Yet, exercise was minimally effective at reversing alterations in gene expression in endothelial and mesenchymal cells in EAT surrounding occluded arteries. These findings lay the foundation for future work focused on the impact of exercise on cell types in EAT.

Resurgence of respiratory syncytial virus with dominance of RSV-B during the 2022-2023 season.

Background: Respiratory syncytial virus (RSV) is a common cause of upper and lower respiratory tract infections. This study aimed to explore the prevalence of respiratory syncytial virus (RSV) and other respiratory viruses in Bulgaria, characterize the genetic diversity of RSV strains, and perform amino acid sequence analyses of RSV surface and internal proteins. Methods: Clinical and epidemiological data and nasopharyngeal swabs were prospectively collected from patients with acute respiratory infections between October 2020 and May 2023. Real-time PCR for 13 respiratory viruses, whole-genome sequencing, phylogenetic, and amino acid analyses were performed. Results: This study included three epidemic seasons (2020-2021, 2021-2022, and 2022-2023) from week 40 of the previous year to week 20 of the following year. Of the 3,047 patients examined, 1,813 (59.5%) tested positive for at least one viral respiratory pathogen. RSV was the second most detected virus (10.9%) after SARS-CoV-2 (22%). Coinfections between RSV and other respiratory viruses were detected in 68 cases, including 14 with SARS-CoV-2. After two seasons of low circulation, RSV activity increased significantly during the 2022-2023 season. The detection rates of RSV were 3.2, 6.6, and 13.7% in the first, second, and third seasons, respectively. RSV was the most common virus found in children under 5 years old with bronchiolitis (40%) and pneumonia (24.5%). RSV-B drove the 2022-2023 epidemic. Phylogenetic analysis indicated that the sequenced RSV-B strains belonged to the GB5.0.5a and GB5.0.6a genotypes. Amino acid substitutions in the surface and internal proteins, including the F protein antigenic sites were identified compared to the BA prototype strain. Conclusion: This study revealed a strong resurgence of RSV in the autumn of 2022 after the lifting of anti-COVID-19 measures, the leading role of RSV as a causative agent of serious respiratory illnesses in early childhood, and relatively low genetic diversity in circulating RSV strains.

Plasma-Driven Tuning of Dielectric Permittivity in Graphene.

Materials with tunable negative electromagnetic performance, i.e., where dielectric permittivity becomes negative, have long been pursued in materials research due to their peculiar electromagnetic (EM) characteristics. Here, this promising feature is reported in materials on the case of plasma-synthesized nitrogen-doped graphene sheets with tunable permittivity over a wide (1-40 GHz) frequency range. Selectively incorporated nitrogen atoms in a graphene scaffold tailor the electronic structure in a way that provides an ultra-low energy (0.5-2 eV) 2D surface plasmon excitation, leading to subunitary and negative dielectric constant values in the Ka-band, from 30 up to 40 GHz. By allowing the tailoring of structures at atomic scale, this novel plasma-based approach creates a new paradigm for designing 2D nanomaterials like nanocarbons with controllable and tunable permittivity, opening a path to the next generation of 2D metamaterials.

Benzodiazepine and Zolpidem-Induced Bradycardia: A Case Report.

Benzodiazepines and zolpidem are commonly used in suicide attempts. They have previously been thought to have very few side effects outside of central nervous system depression, and are considered relatively safe even in overdoses. Cardiovascular manifestations of these overdoses are exceedingly rare. We depict a case where an unknown woman appearing to be in her 50s presented to our emergency department somnolent after a large ingestion of alprazolam, clonazepam, and zolpidem. During the evaluation, the patient became bradycardic to 35 beats per minute on the monitor, which responded to atropine administration. Therefore, it is important for an emergency medicine provider to be aware that both benzodiazepine and zolpidem overdoses can cause profound sinus bradycardia, which can respond to atropine.

Vertebral Artery Dissection.

Vertebral artery dissections are a rare pathology that carries a high risk of stroke in a younger population. They may be caused by minor mechanisms and the index of suspicion should be high. Treatment with anticoagulation or antiplatelets should follow if no surgical management is indicated.We describe a case of a female in her 30s who fell backward off a swing and rolled over her head and complained of continued posterior neck pain. The patient was found to have a vertebral artery dissection on MRI. The patient was then anticoagulated with high-dose apixaban and low-dose aspirin.The emergency medicine provider should be aware of possible low-impact mechanisms that can cause vertebral artery dissection and should have a high index of suspicion. If surgical management is not indicated, anticoagulation should be initiated.

Mantis: high-throughput 4D imaging and analysis of the molecular and physical architecture of cells.

High-throughput dynamic imaging of cells and organelles is essential for understanding complex cellular responses. We report Mantis, a high-throughput 4D microscope that integrates two complementary, gentle, live-cell imaging technologies: remote-refocus label-free microscopy and oblique light-sheet fluorescence microscopy. Additionally, we report shrimPy, an open-source software for high-throughput imaging, deconvolution, and single-cell phenotyping of 4D data. Using Mantis and shrimPy, we achieved high-content correlative imaging of molecular dynamics and the physical architecture of 20 cell lines every 15 minutes over 7.5 hours. This platform also facilitated detailed measurements of the impacts of viral infection on the architecture of host cells and host proteins. The Mantis platform can enable high-throughput profiling of intracellular dynamics, long-term imaging and analysis of cellular responses to perturbations, and live-cell optical screens to dissect gene regulatory networks.

Protein-Rich Rafts in Hybrid Polymer/Lipid Giant Unilamellar Vesicles.

Considerable attention has been dedicated to lipid rafts due to their importance in numerous cell functions such as membrane trafficking, polarization, and signaling. Next to studies in living cells, artificial micrometer-sized vesicles with a minimal set of components are established as a major tool to understand the phase separation dynamics and their intimate interplay with membrane proteins. In parallel, mixtures of phospholipids and certain amphiphilic polymers simultaneously offer an interface for proteins and mimic this segregation behavior, presenting a tangible synthetic alternative for fundamental studies and bottom-up design of cellular mimics. However, the simultaneous insertion of complex and sensitive membrane proteins is experimentally challenging and thus far has been largely limited to natural lipids. Here, we present the co-reconstitution of the proton pump bo3 oxidase and the proton consumer ATP synthase in hybrid polymer/lipid giant unilamellar vesicles (GUVs) via fusion/electroformation. Variations of the current method allow for tailored reconstitution protocols and control of the vesicle size. In particular, mixing of protein-free and protein-functionalized nanosized vesicles in the electroformation film results in larger GUVs, while separate reconstitution of the respiratory enzymes enables higher ATP synthesis rates. Furthermore, protein labeling provides a synthetic mechanism for phase separation and protein sequestration, mimicking lipid- and protein-mediated domain formation in nature. The latter means opens further possibilities for re-enacting phenomena like supercomplex assembly or symmetry breaking and enriches the toolbox of bottom-up synthetic biology.

Radiofrequency dielectric spectroscopy study: Effects of pH, hydrogen bond donors and acceptors on the attachment of spectrin skeleton to the lipid membrane of erythrocytes.

Band 3 protein and glycophorin C are the two major integral proteins of the lipid membrane of human red blood cells (RBCs). They are attached from below to a network of elastic filamentous spectrin, the third major RBC membrane protein. The binding properties of the attachments to spectrin affect the shape and deformability of RBCs. We addressed band 3 and glycophorin C attachments to spectrin by measuring the strength of two recently discovered radiofrequency dielectric relaxations, ßsp (1.4 MHz) and γ1sp (9 MHz), that are observable as changes in the complex admittance of RBCs in medium. In medium at pH 5.2, and also in media with protic substances (formamide, methylformamide, or urea), the ßsp relaxation became inhibited that is attributable to detachment of glycophorin C from spectrin. In medium at pH 9.2, we observed inhibition of γ1sp relaxation attributable to detachment of band 3 from spectrin, as also was seen in media with aprotic substances difluoropyridine, dimethylsolfoxide, dimethylformamide, acetone, sodium tetrakis(4-fluorophenyl)borate), chlorpromazine, thioridazine and trifluopiperazine. The viscogenic cosolvents (glycerol, ethylene glycol, or i-erythritol) inhibited both the ßsp and γ1sp relaxations and significantly lowered their characteristic frequencies. Our observations indicate that the glycophorin C attachment to spectrin has nucleophilic centers whose saturation disconnects this attachment and inhibits the ßsp relaxation, whereas at band 3-spectrin attachment site, it is the saturation of electrophilic centers that weakens this attachment and inhibits the γ1sp relaxation.

From Traditional Dairy Product "Katak" to Beneficial Lactiplantibacillus plantarum Strains.

Traditional milk products, widely consumed in many countries for centuries, have been drawing renewed attention in recent years as sources of bacteria with possible bioprotective properties. One such product for which only limited information exists is the traditional Bulgarian "katak". This fermented yogurt-like product, renowned for its taste and long-lasting properties, possesses specific sensory characteristics. In this study, 18 lactic acid bacteria (LABs) were isolated from artisanal samples made in the Northwest part of Bulgaria. A polyphasic taxonomic approach combining classical phenotypic and molecular taxonomic methods, such as multiplex PCR, 16S rDNA sequencing, and MALDI-TOF MS, was applied, leading to the identification of 13 strains. The dominance of Lactiplantibacillus plantarum was confirmed. In vitro tests with the identified strains in model systems showed a promising broad strain-specific spectrum of activity against food-borne and human pathogens (Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli). Non-purified Lactobacillus postbiotics, produced during fermentation in skimmed and soya milks and in MRS broth, were estimated as limiting agents of virulence factors. The LAB's production of lactate, acetate, and butyrate is a promising probiotic feature. A further characterization of the active strains and analysis of the purified post-metabolites are needed and are still in progress.

Ultra-narrow inhomogeneous spectral distribution of telecom-wavelength vanadium centres in isotopically-enriched silicon carbide.

Spin-active quantum emitters have emerged as a leading platform for quantum technologies. However, one of their major limitations is the large spread in optical emission frequencies, which typically extends over tens of GHz. Here, we investigate single V4+ vanadium centres in 4H-SiC, which feature telecom-wavelength emission and a coherent S = 1/2 spin state. We perform spectroscopy on single emitters and report the observation of spin-dependent optical transitions, a key requirement for spin-photon interfaces. By engineering the isotopic composition of the SiC matrix, we reduce the inhomogeneous spectral distribution of different emitters down to 100 MHz, significantly smaller than any other single quantum emitter. Additionally, we tailor the dopant concentration to stabilise the telecom-wavelength V4+ charge state, thereby extending its lifetime by at least two orders of magnitude. These results bolster the prospects for single V emitters in SiC as material nodes in scalable telecom quantum networks.

Single-nucleus transcriptomics of epicardial adipose tissue from females reveals exercise control of innate and adaptive immune cells.

Coronary artery disease (CAD) is a leading cause of death in women. Although exercise mitigates CAD, the mechanisms by which exercise impacts epicardial adipose tissue (EAT) are unknown. We hypothesized that exercise promotes an anti-inflammatory microenvironment in EAT from female pigs. Yucatan pigs (n=7) were assigned to sedentary (Sed) or exercise (Ex) treatments and coronary arteries were occluded (O) with an ameroid to mimic CAD or remained non-occluded (N). EAT was collected for bulk and single nucleus transcriptomic sequencing (snRNA-seq). Exercise upregulated G-protein coupled receptor, S100 family, and FAK pathways and downregulated the coagulation pathway. Exercise increased the interaction between immune, endothelial, and mesenchymal cells in the insulin-like growth factor pathway and between endothelial and other cell types in the platelet endothelial cell adhesion molecule 1 pathway. Sub-clustering revealed nine cell types in EAT with fibroblast and macrophage populations predominant in O-Ex EAT and T cell population predominant in N-Ex EAT. Coronary occlusion impacted the largest number of genes in T and endothelial cells. Genes related to fatty acid metabolism were the most highly upregulated in non-immune cells from O-Ex EAT. Sub-clustering of endothelial cells revealed that N-Ex EAT separated from other treatments. In conclusion, aerobic exercise increased interaction amongst immune and mesenchymal and endothelial cells in female EAT. Exercise was minimally effective at reversing alterations in gene expression in endothelial and mesenchymal cells in EAT surrounding occluded arteries. These findings lay the foundation for future work focused on the impact of exercise on cell types in EAT.

Induced regeneration of articular cartilage - identification of a dormant regeneration program for a non-regenerative tissue.

A mouse organoid culture model was developed to regenerate articular cartilage by sequential treatment with BMP2 and BMP9 (or GDF2) that parallels induced joint regeneration at digit amputation wounds in vivo. BMP9-induced chondrogenesis was used to identify clonal cell lines for articular chondrocyte and hypertrophic chondrocyte progenitor cells from digit fibroblasts. A protocol that includes cell aggregation enhanced by BMP2 followed by BMP9-induced chondrogenesis resulted in the differentiation of organized layers of articular chondrocytes, similar to the organization of middle and deep zones of articular cartilage in situ, and retained a differentiated phenotype following transplantation. In addition, the differentiation of a non-chondrogenic connective tissue layer containing articular chondrocyte progenitor cells demonstrated that progenitor cell sequestration is coupled with articular cartilage differentiation at a clonal level. The studies identify a dormant endogenous regenerative program for a non-regenerative tissue in which fibroblast-derived progenitor cells can be induced to initiate morphogenetic and differentiative programs that include progenitor cell sequestration. The identification of dormant regenerative programs in non-regenerative tissues such as articular cartilage represents a novel strategy that integrates regeneration biology with regenerative medicine.

Genomic Characterization of IMP-Producing Pseudomonas aeruginosa in Bulgaria Reveals the Emergence of IMP-100, a Novel Plasmid-Mediated Variant Coexisting with a Chromosomal VIM-4.

Multidrug-resistant (MDR) Pseudomonas aeruginosa infections represent a major public health concern and require comprehensive understanding of their genetic makeup. This study investigated the first occurrence of imipenemase (IMP)-carrying P. aeruginosa strains from Bulgaria. Whole genome sequencing identified a novel plasmid-mediated IMP-100 allele located in a a novel In4886 integron embedded in a putative Tn7700 transposon. Two other closely related chromosomal IMP variants, IMP-13 and IMP-84, were also detected. The IMP-producers were resistant to last-line drugs including cefiderocol (CFDC) (two out of three) and susceptible to colistin. The IMP-13/84 cassettes were situated in a In320 integron inserted in a Tn5051-like transposon as previously reported. Lastly, the p4782-IMP plasmid rendered the PA01 transformant resistant to CFDC, suggesting a transferable CFDC resistance. A variety of virulence factors associated with adhesion, antiphagocytosis, iron uptake, and quorum sensing, as well as secretion systems, toxins, and proteases, were confirmed, suggesting significant pathogenic potential consistent with the observed strong biofilm formation. The emergence of IMP-producing MDR P. aeruginosa is alarming as it remains unsusceptible even to last-generation drugs like CFDC. Newly detected IMP-100 was even located in a CFDC-resistant XDR strain.