A5040314793- Bacterial biofilms and quorum sensing
- Antibiotic Resistance in Bacteria
- Antimicrobial Peptides and Activities
- Cystic Fibrosis Research Advances
- Immune Response and Inflammation
- Microbial Community Ecology and Physiology
- Legionella and Acanthamoeba research
- Inhalation and Respiratory Drug Delivery
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- Antimicrobial agents and applications
- Immunotherapy and Immune Responses
- Bacterial Genetics and Biotechnology
- Mycobacterium research and diagnosis
- Vibrio bacteria research studies
- Facial Rejuvenation and Surgery Techniques
- Infections and bacterial resistance
- Antimicrobial Resistance in Staphylococcus
- Oral microbiology and periodontitis research
- Wound Healing and Treatments
- Innovative Microfluidic and Catalytic Techniques Innovation
- Bacterial Identification and Susceptibility Testing
- Biochemical and Structural Characterization
- Pediatric health and respiratory diseases
- Dermatologic Treatments and Research
- Microbial Fuel Cells and Bioremediation
University of Copenhagen
2013-2022
Rigshospitalet
2012-2018
Copenhagen University Hospital
2013-2014
Columbia University
2011
Technical University of Denmark
2006-2010
Inserm
2008
Sorbonne Université
2008
Hôpital Saint-Antoine
2008
In relation to emerging multiresistant bacteria, development of antimicrobials and new treatment strategies infections should be expected become a high-priority research area. Quorum sensing (QS), communication system used by pathogenic bacteria like Pseudomonas aeruginosa synchronize the expression specific genes involved in pathogenicity, is possible drug target. Previous vitro vivo studies revealed significant inhibition P. QS crude garlic extract. By bioassay-guided fractionation...
ABSTRACT During infection, Pseudomonas aeruginosa employs bacterial communication (quorum sensing [QS]) to coordinate the expression of tissue-damaging factors. QS-controlled gene plays a pivotal role in virulence P. , and QS-deficient mutants cause less severe infections animal infection models. Treatment cystic fibrosis (CF) patients chronically infected with macrolide antibiotic azithromycin (AZM) has been demonstrated improve clinical outcome. Several studies indicate that AZM may...
For a chronic infection to be established, bacteria must able cope with hostile conditions such as low iron levels, oxidative stress, and clearance by the host defense, well antibiotic treatment. It is generally accepted that biofilm formation facilitates tolerance these adverse conditions. However, microscopic investigations of samples isolated from sites infections seem suggest some do not need attached surfaces in order establish infections. In this study we employed scanning electron...
Polymorphonuclear neutrophilic leukocytes (PMNs) play a central role in innate immunity, where they dominate the response to infections, particular cystic fibrosis lung. PMNs are phagocytic cells that produce wide range of antimicrobial agents aimed at killing invading bacteria. However, opportunistic pathogen Pseudomonas aeruginosa can evade destruction by and thus cause persistent infections. In this study, we show biofilm P. recognize presence attracted direct information their fellow...
ABSTRACT Foods with health-promoting effects beyond nutritional values have been gaining increasing research focus in recent years, although not much has published on this subject relation to bacterial infections. With respect treatment, a novel antimicrobial strategy, which is expected transcend problems selective pressures for antibiotic resistance, interrupt communication, also known as quorum sensing (QS), by means of signal antagonists, the so-called QS inhibitors (QSIs). Furthermore,...
Many of the virulence factors produced by opportunistic human pathogen Pseudomonas aeruginosa are quorum‐sensing (QS) regulated. Among these rhamnolipids, which have been shown to cause lysis several cellular components immune system, e.g. monocyte‐derived macrophages and polymorphonuclear leukocytes (PMNs). We previously that rhamnolipids P. necrotic death PMNs in vitro . This raises possibility may function as a ‘biofilm shield’ vivo , contributes significantly increased tolerance biofilms...
ObjectivesQuorum sensing (QS)-deficient Pseudomonas aeruginosa biofilms formed in vitro are more susceptible to tobramycin than QS-proficient P. biofilms, and combination treatment with a QS inhibitor (QSI) shows synergistic effects on the killing of biofilms. We extended these results an vivo foreign-body biofilm model. The effect initiated prophylactically was compared 11 days post-insertion.
Bacterial biofilms are known to be extremely tolerant toward antibiotics and other antimicrobial agents. These cause the persistence of chronic infections. Since rarely resolve these infections, only effective treatment infections is surgical removal infected implant, tissue, or organ thereby biofilm. Acetic acid for its effect on bacteria in general, but has never been thoroughly tested efficacy against bacterial biofilms. In this article, we describe complete eradication both Gram-positive...
Cystic fibrosis (CF) patients have increased susceptibility to chronic lung infections by Pseudomonas aeruginosa, but the ecophysiology within CF during is poorly understood. The aim of this study was elucidate in vivo growth physiology P. aeruginosa lungs chronically infected patients. A novel, quantitative peptide nucleic acid (PNA) fluorescence situ hybridization (PNA-FISH)-based method used estimate rates directly tissue samples from and a mouse model. rate did not correlate with...
Bacterial biofilms are imaged by various kinds of microscopy including confocal laser scanning (CLSM) and electron (SEM). One limitation CLSM is its restricted magnification, which resolved the use SEM that provides high-magnification spatial images how single bacteria located interact within biofilm. However, conventional limited requirement dehydration samples during preparation. As consist mainly water, specimen might alter morphology. High magnification yet authentic important to...
Alginate beads represent a simple and highly reproducible in vitro model system for diffusion-limited bacterial growth. In this study, alginate were inoculated with Pseudomonas aeruginosa followed up to 72 h. Confocal microscopy revealed that P. formed dense clusters similar size vivo aggregates observed ex cystic fibrosis lungs chronic wounds. Bacterial primarily grew the bead periphery decreased abundance toward center of bead. Microsensor measurements showed O2 concentration rapidly...
Through several observational and mechanistic studies, microbial infection is known to promote cardiovascular disease. Direct of the vessel wall, along with risk factors, hypothesized play a key role in atherogenesis by promoting an inflammatory response leading endothelial dysfunction generating proatherogenic prothrombotic environment ultimately clinical manifestations disease, e.g., acute myocardial infarction or stroke. There are many reports DNA isolation even few studies viable...
The microtiter assay is one of the most widely used methods for assessing biofilm formation. Though it has high throughput, this known its substantial deviation from experiment to experiment, and even well well. Since constitutes pillars research, was decided examine wells a plate directly during growth, treatment, steps involved in crystal violet (CV) measurements. An inverted Zeiss LSM 880 confocal laser scanning microscope visualize quantify biomass plate. Green fluorescent protein-tagged...
ABSTRACT For the past 150 years, bacteria have been investigated primarily in liquid batch cultures. Contrary to most expectations, these cultures are not homogeneous mixtures of single-cell bacteria, because free-floating bacterial aggregates eventually develop These share characteristics with biofilms, such as increased antibiotic tolerance. We how and what influences this development Pseudomonas aeruginosa . focused on method inoculation affected aggregation by assessing aggregate...
Opportunistic pathogenic bacteria can engage in biofilm-based infections that evade immune responses and develop into chronic conditions. Because conventional antimicrobials cannot efficiently eradicate biofilms, there is an urgent need to alternative measures combat biofilm infections. It has recently been established the secondary messenger cyclic diguanosine monophosphate (c-di-GMP) functions as a positive regulator of formation several different bacteria. In present study we investigated...
Achromobacter xylosoxidans is an environmental opportunistic pathogen, which infects increasing number of immunocompromised patients. In this study we combined genomic analysis a clinical isolated A. strain with phenotypic investigations its important pathogenic features. We present complete assembly the genome NH44784-1996, isolate from cystic fibrosis patient obtained in 1996. The NH44784-1996 contains approximately 7 million base pairs 6390 potential protein-coding sequences. identified...
Chronic Pseudomonas aeruginosa lung infection is the most severe complication in patients with cystic fibrosis (CF). The characterized by formation of biofilm surrounded numerous polymorphonuclear leukocytes (PMNs) and strong O2 depletion endobronchial mucus. We have reported that mainly consumed activated PMNs, while consumption aerobic respiration diminutive nitrous oxide (N2O) produced infected CF sputum. This suggests growth rates P. lungs sputum may result from anaerobic using...
ABSTRACT Extracellular DNA (eDNA) plays an important role in both the aggregation of bacteria and interaction resulting biofilms with polymorphonuclear leukocytes (PMNs) during inflammatory response. Here, transmission electron confocal scanning laser microscopy were used to examine between Pseudomonas aeruginosa PMNs a murine implant model lung tissue from chronically infected cystic fibrosis patients. PNA FISH, staining, labeling PMN thymidine analogue immunohistochemistry applied localize...
The ability of bacteria to aggregate and form biofilms impairs phagocytosis by polymorphonuclear leukocytes (PMNs). aim this study was examine if the size aggregates is critical for successful how bacterial evade phagocytosis. We investigated live interaction between PMNs Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli epidermidis using confocal scanning laser microscopy. Aggregate significantly affected outcome larger were less likely be phagocytized. Aggregates S. also...