Nanoparticles and atherosclerosis : resolving the paradox

Air pollution is increasingly recognised as an important and modifiable risk factor for cardiovascular disease. Exposure is associated with a range of adverse cardiovascular events including hospital admissions with angina and myocardial infarction, and with cardiovascular death. The main arbiter of these adverse health effects appears to be combustion-derived nanoparticles that incorporate reactive organic and transition metal components. Through the induction of cellular oxidative stress and pro-inflammatory pathways, these nanoparticles exert detrimental effects on platelets, vasculature and myocardium, and can augment the development and progression of atherosclerosis. Over the last 10 years there has been remarkable progress in the development of targeted engineered nanoparticles as contrast agents to enhance cellular and molecular imaging. Ultra-small paramagnetic iron oxide (USPIO) nanoparticles (<100 nm) produce disruptions in the magnetic field of magnetic resonance imaging (MRI) scanners, and a decrease in image intensity in areas where the particles accumulate. USPIO particles are phagocytosed by cells of the monocyte-macrophage system throughout the body including within atheromatous plaques. USPIOs have regulatory approval in the United Kingdom for imaging lymph nodes in breast and prostate cancer as well as FDA approval for parenteral iron-replacement therapy in chronic kidney disease. There is great interest in developing USPIO and other nanoparticle contrast agents for imaging atherosclerosis. The delivery of engineered nanoparticles (ENPs) directly into the bloodstream to provide enhanced imaging of the unstable atheromatous plaque may assist in the diagnosis of plaque rupture and may ultimately permit targeted delivery of therapies directly to the site of vascular injury. However, these particles once blood-borne may alter monocyte-macrophage function and activate circulating platelets with adverse effects on clinical outcomes. Previously it has been shown that inhalation of combustion-derived nanoparticles results in increases in platelet-monocyte aggregation and thrombus formation in healthy volunteers. These combustion derived nanoparticles share structural similarities with engineered nanoparticles designed for intravascular infusion. This raises an obvious paradoxical question: can engineered nanoparticles designed for medical use mediate similar effects to combustion derived nanoparticles in susceptible populations? My thesis addresses this question and describes a series of complimentary experimental and clinical studies to investigate the effects of engineered nanoparticles on platelet function and thrombogenesis using commercial and clinically available nanoparticles. I found that cationic nanoparticles caused platelet activation and aggregation in vitro, whereas, anionic nanoparticles caused inflammation and up-regulated adhesion molecule ICAM-1 in monocyte derived macrophages indicating that nanoparticles have different toxicological properties in different biological conditions. Using an ex vivo model of thrombus formation, the Badimon chamber, I observed that USPIO nanoparticles added to flowing native whole blood in an extra-corporeal circuit increased platelet rich thrombus formation under high shear conditions compared to saline control in healthy volunteers. These studies were repeated in patients with abdominal aortic aneurysms who received intra-venous systemic infusions of USPIO to enhance MRI imaging. I demonstrated up-regulation in markers of platelet activation and more platelet rich thrombus formation in the Badimon chamber one hour following systemic delivery of USPIO. In summary I have demonstrated that medical nanoparticles influence platelet activation in patients with cardiovascular disease and have pro-thrombotic effects in an ex-vivo model of in both healthy persons and susceptible patients. In light of this data and to ensure the safe future development of engineered nanoparticles for medical use platelet activation assays and follow-up monitoring of patients should be considered routine in both the developmental and clinical stages of engineered nanoparticle use

Genomic diversity of Lactobacillus salivarius

Lactobacillus salivarius is unusual among the lactobacilli due to its multireplicon genome architecture. The circular megaplasmids harboured by L. salivarius strains encode strain-specific traits for intestinal survival and probiotic activity. L. salivarius strains are increasingly being exploited for their probiotic properties in humans and animals. In terms of probiotic strain selection, it is important to have an understanding of the level of genomic diversity present in this species. Comparative genomic hybridization (CGH) and multilocus sequence typing (MLST) were employed to assess the level of genomic diversity in L. salivarius. The wellcharacterised probiotic strains L. salivarius UCC118 was employed as a genetic reference strain. The group of test strains were chosen to reflect the range of habitats from which L. salivarius strains are frequently recovered, including human, animal, and environmental sources. Strains of L. salivarius were found to be genetically diverse when compared to the UCC118 genome. The most conserved strains were human GIT isolates, while the greatest level of divergence were identified in animal associated isolates. MLST produced a better separation of the test strains according to their isolation origins, than that produced by CGHbased strain clustering. The exopolysaccharide (EPS) associated genes of L. salivarius strains were found to be highly divergent. The EPS-producing phenotype was found to be carbonsource dependent and inversely related to a strain's ability to produce a biofilm. The genome of the porcine isolate L. salivarius JCM1046 was shown by sequencing to harbour four extrachromosomal replicons, a circular megaplasmid (pMP1046A), a putative chromid (pMP1046B), a linear megaplasmid (pLMP1046) and a smaller circular plasmid (pCTN1046) which contains an integrated Tn916-like element (Tn6224), which carries the tetracycline resistance gene tetM. pLMP1046 represents the first sequence of a linear plasmid in a Lactobacillus species. Dissemination of antibiotic resistance genes among species with food or probiotic-association is undesirable, and the identification of Tn6224-like elements in this species has implications for strain selection for probiotic applications. In summary, this thesis used a comparative genomics approach to examine the level of genotypic diversity in L. salivarius, a species which contains probiotic strains. The genome sequence of strain JCM1046 provides additional insight into the spectrum of extrachromosomal replicons present in this species

What Determines Creativity and Innovation in Organizations: A Post Crisis evaluation in the Bank of Cyprus

ABSTRACT In today’s competitive and constantly changing environment many researchers claim that it is important for organizations to innovate in order to survive. As most of this innovation is a source of the creative thoughts of individual employees, it is significant for any organization to ensure employees work under such conditions that would enhance and promote their creative thought. This study examined the characteristics of the work environment at the Bank of Cyprus and the perceptions of its personnel, before and after a major crisis which included the absorption of another bank’s assets including its personnel, branch closures, salary reductions and a voluntary retirement scheme. The purpose of this research was to identify changes in the work environment and in personnel perceptions as a result of the crisis and how these changes could have affected creativity and innovation among employees. Semi-structured interviews were held among a sample of 15 bank employees from different areas of the Bank and thematic analysis was performed that identified five major themes of importance. Specifically, in relation to the five themes which are limited organizational encouragement towards creative thought, limited resources to support creativity and innovation, changing relationships with management, team role changes and shift in perceptions and emotions, employees perceived worsening of conditions after the crisis and, as a consequence, a negative effect on creativity and innovation. Most mentioned changes in the work environment as a result of the crisis included extensive time pressure, decrease of perceived leadership support, problems in team adaptation to the new situation and the development of negative feelings and emotions, most notably fear and insecurity. The evaluation of personnel perceptions of the changes in the work environment of the Bank after the crisis, indicate that such a crisis could be associated mostly with negative effects on creativity and innovation

Internal Cycling in an Urban Drinking Water Reservoir

Indiana University-Purdue University Indianapolis (IUPUI)The focus of this study was to document phosphorus (P) and metal cycling in the Eagle Creek Reservoir (ECR), located in Indianapolis, central Indiana. Eagle Creek Reservoir serves the drinking water needs of over 80,000 residents. Within the last several years, algal blooms have created stress to the local treatment facility. The objective of this study was to examine how P cycling from oxygen deprived bottom sediments affects the algal bloom productivity. As such, cores were retrieved from different water depths (7 and 16 m) from portions of the reservoir where high surficial concentrations of organic matter and P were found to occur. The dried samples were analyzed for P, sulfur, iron, barium, cadmium, copper, lead, and zinc, using a strong acid digestion technique. The samples were also analyzed for iron-bound P (Fe-P), authigenic P (A-P), detrital P (D-P), organic P (O-P), reducible iron, and reducible manganese, using a sequential extraction technique. The results from the study showed moisture contents ranged from 16 to 76% and organic matter contents ranged from 2 to 12 wt%. The dry bulk densities were determined to be between 0.27 and 1.68 g cm3. The average percentages of P in ECS-1, as determined by the sequential extraction method, were as follows: Fe-P, 66.2%; A-P, 8.1%; D-P, 4.8%; and O-P, 20.9%. The average percentages of P in ECS-3, as determined by the sequential extraction method, were as follows: Fe-P, 77.0%; A-P, 6.5%; D-P, 2.8%; and O-P, 16.7%. To determine relationships between elements, correlations were calculated. When looking as the relationships between the P fractions and reducible Fe, differences were observed between the different water depths. There was less correlation between reducible Fe and Fe-P, and between O-P and Fe-P, in ECS-3, indicating that Fe-P is more efficiently dissolved and recycled in the deep portion of ECR. The study shows that the Fe-P flux, caused by the iron redox cycle, is persistent and will continue to influence algal bloom productivity in the deeper portions of ECR

Haemolytic activity of soil from areas of varying podoconiosis endemicity in Ethiopia

Background: Podoconiosis, non-filarial elephantiasis, is a non-infectious disease found in tropical regions such as Ethiopia, localized in highland areas with volcanic soils cultivated by barefoot subsistence farmers. It is thought that soil particles can pass through the soles of the feet and taken up by the lymphatic system, leading to the characteristic chronic oedema of the lower legs that becomes disfiguring and disabling over time. Methods: The close association of the disease with volcanic soils led us to investigate the characteristics of soil samples in an endemic area in Ethiopia to identify the potential causal constituents. We used the in vitro haemolysis assay and compared haemolytic activity (HA) with soil samples collected in a non-endemic region of the same area in Ethiopia. We included soil samples that had been previously characterized, in addition we present other data describing the characteristics of the soil and include pure phase mineral standards as comparisons. Results: The bulk chemical composition of the soils were statistically significantly different between the podoconiosis-endemic and non-endemic areas, with the exception of CaO and Cr. Likewise, the soil mineralogy was statistically significant for iron oxide, feldspars, mica and chlorite. Smectite and kaolinite clays were widely present and elicited a strong HA, as did quartz, in comparison to other mineral phases tested, although no strong difference was found in HA between soils from the two areas. The relationship was further investigated with principle component analysis (PCA), which showed that a combination of an increase in Y, Zr and Al2O3, and a concurrent increase Fe2O3, TiO2, MnO and Ba in the soils increased HA. Conclusion: The mineralogy and chemistry of the soils influenced the HA, although the interplay between the components is complex. Further research should consider the variable biopersistance, hygroscopicity and hardness of the minerals and further characterize the nano-scale particles

Bifidobacterium breve MRx0004 protects against airway inflammation in a severe asthma model by suppressing both neutrophil and eosinophil lung infiltration

All authors were employees of (or in the case of MID, seconded full-time to) 4D Pharma Research Ltd while engaged in the research project. This work was supported by funding provided by 4D Pharma PLC. 4D Pharma Research Ltd owns a family of patent applications which are pending internationally which are derived from International Patent Publication No. WO2016/203223 which protect the treatment of severe asthma using MRx0004. George Grant, Angela Patterson, Imke Mulder, Seanin McCluskey and Emma Raftis are named as inventors for this patent family. The authors declare no other competing interests.Peer reviewedPublisher PD

PAR4 (Protease-Activated Receptor 4) Antagonism with BMS-986120 Inhibits Human Ex Vivo Thrombus Formation

Objective-BMS-986120 is a novel first-in-class oral PAR4 (protease-Activated receptor 4) antagonist with potent and selective antiplatelet effects. We sought to determine for the first time, the effect of BMS-986120 on human ex vivo thrombus formation. Approach and Results-Forty healthy volunteers completed a phase 1 parallel-group PROBE trial (Prospective Randomized Open-Label Blinded End Point). Ex vivo platelet activation, platelet aggregation, and thrombus formation were measured at 0, 2, and 24 hours after (1) oral BMS-986120 (60 mg) or (2) oral aspirin (600 mg) followed at 18 hours with oral aspirin (600 mg) and oral clopidogrel (600 mg). BMS-986120 demonstrated highly selective and reversible inhibition of PAR4 agonist peptide (100 μM)-stimulated P-selectin expression, platelet-monocyte aggregates, and platelet aggregation (P<0.001 for all). Compared with pretreatment, total thrombus area (μm2/mm) at high shear was reduced by 29.2% (95% confidence interval, 18.3%-38.7%; P<0.001) at 2 hours and by 21.4% (9.3%-32.0%; P=0.002) at 24 hours. Reductions in thrombus formation were driven by a decrease in platelet-rich thrombus deposition: 34.8% (19.3%-47.3%; P<0.001) at 2 hours and 23.3% (5.1%-38.0%; P=0.016) at 24 hours. In contrast to aspirin alone, or in combination with clopidogrel, BMS-986120 had no effect on thrombus formation at low shear (P=nonsignificant). BMS-986120 administration was not associated with an increase in coagulation times or serious adverse events. Conclusions-BMS-986120 is a highly selective and reversible oral PAR4 antagonist that substantially reduces platelet-rich thrombus formation under conditions of high shear stress. Our results suggest PAR4 antagonism has major potential as a therapeutic antiplatelet strategy. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT02439190