Influence of quorum sensing signal molecules on biofilm formation in Proteus mirabilis O18

The influence of basis of quorum sensing molecules on Proteus strains is much less known as compared to Pseudomonas or Escherichia. We have previously shown that a series of acylated homoserine lactones (acyl-HSL) does not influence the ureolytic, proteolytic, or hemolytic abilities, and that the swarming motility of Proteus mirabilis rods is strain specific. The aim of the presented study was to find out if the presence of a series of acyl-HSL influences biofilm formation of P. mirabilis laboratory strain belonging to O18 serogroup. This serogroup is characterized by the presence of a unique non-carbohydrate component, namely phosphocholine. Escherichia coli and P. mirabilis O18 strains used in this work contains cloned plasmids encoding fluorescent protein genes with constitutive gene expression. In mixed biofilms in stationary and continuous flow conditions, P. mirabilis O18 overgrow whole culture. P. mirabilis O18 strain has genetically proved a presence of AI–2 quorum sensing system. Differences in biofilm structure were observed depending on the biofilm type and culture methods. From tested acylated homoserine lactones (BHL, HHL, OHL, DHL, dDHL, tDHL), a significant influence had BHL on thickness, structure, and the amount of exopolysaccharides produced by biofilms formed by P. mirabilis O18 pDsRed2

The capsular polysaccharide and lipopolysaccharide structures of two carbapenem resistant Klebsiella pneumoniae outbreak isolates

Carbapenem resistant Klebsiella pneumoniae (CRKP) are isolated with increasing frequency, especially from immunocompromized patients. The capsular polysaccharide (CPS) types of CPKP were not determined. Investigation of two CRKP isolates from a 2011 outbreak at the Clinical Center, the National Institutes of Health, identified a new capsular type shared by the two isolates, similar to K. pneumonia K19 and K34 but structurally different than any published K. pneumoniae CPS repeating unit: The LPS of the two isolates was found to have no O-specific polysaccharide and the chemical structure of the core oligosaccharides agreed with the published data. If this structure type will be prevalent among CPKP isolates, our findings could facilitate rapid diagnosis and help to develop new therapeutic solutions to this antibiotic resistant pathogen. \ua9 2013 Elsevier Inc. All rights reserved.Peer reviewed: YesNRC publication: Ye

Transcriptional diversity during lineage commitment of human blood progenitors

Blood cells derive from hematopoietic stem cells through stepwise fating events. To characterize gene expression programs driving lineage choice, we sequenced RNA from eight primary human hematopoietic progenitor populations representing the major myeloid commitment stages and the main lymphoid stage. We identified extensive cell type–specific expression changes: 6711 genes and 10,724 transcripts, enriched in non–protein-coding elements at early stages of differentiation. In addition, we found 7881 novel splice junctions and 2301 differentially used alternative splicing events, enriched in genes involved in regulatory processes. We demonstrated experimentally cell-specific isoform usage, identifying nuclear factor I/B (NFIB) as a regulator of megakaryocyte maturation—the platelet precursor. Our data highlight the complexity of fating events in closely related progenitor populations, the understanding of which is essential for the advancement of transplantation and regenerative medicine

The prevalence of abnormal glucose regulation in patients with coronary artery disease across Europe: The Euro Heart Survey on diabetes and the heart

Aim The objective behind the Euro Heart Survey on diabetes and the heart was to study the prevalence of abnormal glucose regulation in adult patients with coronary artery disease (CAD). Methods and results The survey engaged 110 centres in 25 countries recruiting 4196 patients referred to a cardiologist due to CAD out of whom 2107 were admitted on an acute basis and 2854 had an elective consultation. Patient data were collected via a web-based case record form. An oral glucose tolerance test (OGTT) was used for the characterisation of the glucose metabolism. Thirty-one per cent of the patients had diabetes. An OGTT was performed on the 1920 patients without known diabetes, of whom 923 had acute and 997 had a stable manifestation of CAD, respectively. In patients with acute CAD, 36% had impaired glucose regulation and 22% newly detected diabetes. In the stable group these proportions were 37% and 14%. Conclusion This survey demonstrates that normal glucose regulation is less common than abnormal glucose regulation in patients with CAD. OGTT easily discloses the glucometabolic state and should be a routine procedure. The knowledge of glucometabolic state among these patients should influence their future management because it has great potential to improve the outcome

Interventional treatment in diabetics in the era of drugeluting stents and compliance to the ESC guidelines: Lessons learned from the Euro Heart Survey Programme

Aims: The objective of the study is to determine the demographics and the in-hospital outcome of diabetic and non-diabetic patients treated with percutaneous coronary interventions (PCI) in Europe, to report the type of equipment and technology used for PCI procedures in diabetics and to clarify whether the treatment of diabetic patients complies with current European Society of Cardiology (ESC) guidelines. Methods and results: A total of 14,458 patients treated with PCI were enrolled from 29 member countries of the ESC between June 2005 and January 2006. Data were collected on patient characteristics and treatment, using new Cardiology Audit and Registration Data standards. In total, 3,603 patients (24.9%) were diabetic. Diabetics were older, more often female and had a higher body mass index than non-diabetics. Diabetics had higher rates of hypercholesterolaemia and hypertension, while current smokers were more frequent in the non-diabetics. Diabetics also had significantly higher rates of previous cardiovascular events. Clopidogrel was administered only in 48.1% of diabetic patients before PCI, while IIb/IIIa inhibitors were 22.9% during PCI. At discharge, there was a major adjustment of treatment with increases in the use of Beta-blocker (80.4%), angiotensin converting enzyme inhibitor (ACEI, 71.3%) and statins (89.8%) compared with on admission (Beta-blocker 60.9%, ACEI 55.0%, statin 63.1%). Inhospital mortality was higher in diabetics (1.8% vs 1.2%) although the in-hospital MACCE rate was not significantly different (3.6% vs 3.0%, p=0.09). Conclusions: Diabetic patients treated with PCI were older with more comorbidity. According to ESC guideline, the under-usage of clopidogrel, GP IIb/IIIa inhibitors should be improved. PCI is now taken as a good opportunity to adjust the use of appropriate medication. © Europa Edition. All rights reserved