Counterflow dielectrophoresis for trypanosome enrichment and detection in blood

Human African trypanosomiasis or sleeping sickness is a deadly disease endemic in sub-Saharan Africa, caused by single-celled protozoan parasites. Although it has been targeted for elimination by 2020, this will only be realized if diagnosis can be improved to enable identification and treatment of afflicted patients. Existing techniques of detection are restricted by their limited field-applicability, sensitivity and capacity for automation. Microfluidic-based technologies offer the potential for highly sensitive automated devices that could achieve detection at the lowest levels of parasitemia and consequently help in the elimination programme. In this work we implement an electrokinetic technique for the separation of trypanosomes from both mouse and human blood. This technique utilises differences in polarisability between the blood cells and trypanosomes to achieve separation through opposed bi-directional movement (cell counterflow). We combine this enrichment technique with an automated image analysis detection algorithm, negating the need for a human operator

What's in the box? Exploring UK players' experiences of loot boxes in games; the conceptualisation and parallels with gambling.

Loot boxes are a popular mechanic within many video games, but it remains unclear if some forms of loot boxes can be seen of as gambling. However, the perspectives of players are often neglected, such as whether they see them as 'fair' game elements and how closely they feel this aligns with gambling. In this paper, we synthesise a conceptualisation for loot boxes through players' actual experience and explore if there are any parallels with gambling. Twenty-one participants who played video games took part in the research through either an interview or online survey. Thematic analysis suggested that six themes were core to exploring loot boxes: Random Chance Effects, Attitudes Towards Content, Implementation, Parallels with Gambling, Game Design, and The Player. The results suggested both indirect and direct parallels with gambling from the players experiences. Implications of game design and classifying loot boxes as gambling are discussed in relation to game design and risk factors of gambling and purchasing behaviour

Shear Strength of Copper Joints Prepared by Low Temperature Sintering of Silver Nanoparticles

In this work, mechanical properties of Cu-to-Cu joint samples prepared by low temperature sintering of Ag nanoparticle paste have been investigated. The silver nanopaste was prepared by a controlled thermal decomposition of an organometallic precursor. The as-synthesized Ag particles were spherical, with an average diameter of 8.5 nm. The Cu-to-Cu joint samples were made by placing a small amount of Ag nanopaste between two polished Cu plates and sintering at 150C, 200C, 220C and 350C in air. A normal load was applied to aid sintering. Mechanical properties were measured by imposing a uniform stress across the sample bond area and measuring the corresponding strain. The application of external load was found to have a positive effect on the material’s mechanical properties. Furthermore, interestingly high values of shear strength were observed.Byly zkoumány mechanické vlastnosti Cu-to-Cu spojů připravených nízkoteplotní sintrací pasty Ag nanočástic. Ag nanopasta byla připravena řízeným tepelným rozkladem organokovových prekurzorů. Syntetizované Ag NPs byly kulovité, o středním průměru 8,5 nm. Cu-to-Cu spoje byly vyrobeny umístěním malého množství Ag nanopasty mezi dvě leštěné Cu desky a sintrováním při 150C, 200C, 220C and 350C na vzduchu. Zatížení bylo použito na k podpoře sintrace. Mechanické vlastnosti byly měřeny stanovením napětí lomu a deformace. Bylo zjištěno, že aplikace vnějšího zatížení má pozitivní vliv na mechanické vlastnosti spoje

Long-Term Accumulation, Biological Effects and Toxicity of BSA-Coated Gold Nanoparticles in the Mouse Liver, Spleen, and Kidneys

Kristina Jakic,1 Michal Selc,1,2 Filip Razga,3 Veronika Nemethova,3 Petra Mazancova,3 Filip Havel,4,5 Michal Sramek,5 Monika Zarska,5 Jan Proska,4 Vlasta Masanova,6 Iveta Uhnakova,6 Peter Makovicky,7 Marta Novotova,8 Vit Vykoukal,9 Andrea Babelova1,2 1Department of Nanobiology, Cancer Research Institute, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia; 2Centre for Advanced Material Application, Slovak Academy of Sciences, Bratislava, Slovakia; 3Selecta Biotech SE, Bratislava, Slovakia; 4Department of Physical Electronics, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague, Czech Republic; 5Department of Genome Integrity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic; 6Department of Metallomics, Faculty of Medicine, Slovak Medical University, Bratislava, Slovakia; 7Department of Molecular Oncology, Cancer Research Institute, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia; 8Department of Cellular Cardiology, Institute of Experimental Endocrinology, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia; 9Department of Chemistry, Faculty of Science, Masaryk University, Brno, Czech RepublicCorrespondence: Andrea Babelova, Department of Nanobiology, Cancer Research Institute, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia, Tel +421-2-32295-189, Fax +421-2-5477-4284, Email [email protected]: Gold nanoparticles are promising candidates as vehicles for drug delivery systems and could be developed into effective anticancer treatments. However, concerns about their safety need to be identified, addressed, and satisfactorily answered. Although gold nanoparticles are considered biocompatible and nontoxic, most of the toxicology evidence originates from in vitro studies, which may not reflect the responses in complex living organisms.Methods: We used an animal model to study the long-term effects of 20 nm spherical AuNPs coated with bovine serum albumin. Mice received a 1 mg/kg single intravenous dose of nanoparticles, and the biodistribution and accumulation, as well as the organ changes caused by the nanoparticles, were characterized in the liver, spleen, and kidneys during 120 days.Results: The amount of nanoparticles in the organs remained high at 120 days compared with day 1, showing a 39% reduction in the liver, a 53% increase in the spleen, and a 150% increase in the kidneys. The biological effects of chronic nanoparticle exposure were associated with early inflammatory and fibrotic responses in the organs and were more pronounced in the kidneys, despite a negligible amount of nanoparticles found in renal tissues.Conclusion: Our data suggest, that although AuNPs belong to the safest nanomaterial platforms nowadays, due to their slow tissue elimination leading to long-term accumulation in the biological systems, they may induce toxic responses in the vital organs, and so understanding of their long-term biological impact is important to consider their potential therapeutic applications. Keywords: AuNPs, in vivo, long-term accumulation, biodistribution, inflammation, fibrosi

Low-density lipoprotein electronegativity and risk of death after acute coronary syndromes: A case-cohort analysis.

BACKGROUND AND AIMS Low-density lipoprotein (LDL)-cholesterol (LDL-C) promotes atherosclerotic cardiovascular disease (ASCVD), with changes in LDL electronegativity modulating its pro-atherogenic/pro-thrombotic effects. Whether such alterations associate with adverse outcomes in patients with acute coronary syndromes (ACS), a patient population at particularly high cardiovascular risk, remains unknown. METHODS This is a case-cohort study using data from a subset of 2619 ACS patients prospectively recruited at four university hospitals in Switzerland. Isolated LDL was chromatographically separated into LDL particles with increasing electronegativity (L1-L5), with the L1-L5 ratio serving as a proxy of overall LDL electronegativity. Untargeted lipidomics revealed lipid species enriched in L1 (least) vs. L5 (most electronegative subfraction). Patients were followed at 30 days and 1 year. The mortality endpoint was reviewed by an independent clinical endpoint adjudication committee. Multivariable-adjusted hazard ratios (aHR) were calculated using weighted Cox regression models. RESULTS Changes in LDL electronegativity were associated with all-cause mortality at 30 days (aHR, 2.13, 95% CI, 1.07-4.23 per 1 SD increment in L1/L5; p=.03) and 1 year (1.84, 1.03-3.29; p=.04), with a notable association with cardiovascular mortality (2.29; 1.21-4.35; p=.01; and 1.88; 1.08-3.28; p=.03). LDL electronegativity superseded several risk factors for the prediction of 1-year death, including LDL-C, and conferred improved discrimination when added to the updated GRACE score (area under the receiver operating characteristic curve 0.74 vs. 0.79, p=.03). Top 10 lipid species enriched in L1 vs. L5 were: cholesterol ester (CE) (18:2), CE (20:4), free fatty acid (FA) (20:4), phosphatidyl-choline (PC) (36:3), PC (34:2), PC (38:5), PC (36:4), PC (34:1), triacylglycerol (TG) (54:3), and PC (38:6) (all p < .001), with CE (18:2), CE (20:4), PC (36:3), PC (34:2), PC (38:5), PC (36:4), TG (54:3), and PC (38:6) independently associating with fatal events during 1-year of follow-up (all p < .05). CONCLUSIONS Reductions in LDL electronegativity are linked to alterations of the LDL lipidome, associate with all-cause and cardiovascular mortality beyond established risk factors, and represent a novel risk factor for adverse outcomes in patients with ACS. These associations warrant further validation in independent cohorts

Electrically addressable vesicles: Tools for dielectrophoresis metrology

Dielectrophoresis (DEP) has emerged as an important tool for the manipulation of bioparticles ranging from the submicron to the tens of microns in size. Here we show the use of phospholipid vesicle electroformation techniques to develop a new class of test particles with specifically engineered electrical propserties to enable identifiable dielectrophoretic responses in microfabricated systems. These electrically addressable vesicles (EAVs) enable the creation of electrically distinct populations of test particles for DEP. EAVs offer control of both their inner aqueous core and outer membrane properties; by encapsulating solutions of different electrolyte strength inside the vesicle and by incorporating functionalized phospholipids containing poly(ethylene glycol) (PEG) brushes attached to their hydrophilic headgroup in the vesicle membrane, we demonstrate control of the vesicles’ electrical polarizabilities. This combined with the ability to encode information about the properties of the vesicle in its fluorescence signature forms the first steps toward the development of EAV populations as metrology tools for any DEP-based microsystem.National Institutes of Health (U.S.) (Grant RR199652)National Institutes of Health (U.S.) (Grant EB005753)Merck/CSBi (Fellowship)Solomon Buchsbaum AT&T Research Fun

Connection between Telomerase Activity in PBMC and Markers of Inflammation and Endothelial Dysfunction in Patients with Metabolic Syndrome

Metabolic syndrome (MS) is a constellation of metabolic derangements associated with vascular endothelial dysfunction and oxidative stress and is widely regarded as an inflammatory condition, accompanied by an increased risk for cardiovascular disease. The present study tried to investigate the implications of telomerase activity with inflammation and impaired endothelial function in patients with metabolic syndrome. Telomerase activity in circulating peripheral blood mononuclear cells (PBMC), TNF-α, IL-6 and ADMA were monitored in 39 patients with MS and 20 age and sex-matched healthy volunteers. Telomerase activity in PBMC, TNF-α, IL-6 and ADMA were all significantly elevated in patients with MS compared to healthy volunteers. PBMC telomerase was negatively correlated with HDL and positively correlated with ADMA, while no association between TNF-α and IL-6 was observed. IL-6 was increasing with increasing systolic pressure both in the patients with MS and in the healthy volunteers, while smoking and diabetes were positively correlated with IL-6 only in the patients' group. In conclusion, in patients with MS characterised by a strong dyslipidemic profile and low diabetes prevalence, significant telomerase activity was detected in circulating PBMC, along with elevated markers of inflammation and endothelial dysfunction. These findings suggest a prolonged activity of inflammatory cells in the studied state of this metabolic disorder that could represent a contributory pathway in the pathogenesis of atherosclerosis

Label-free cell separation and sorting in microfluidic systems

Cell separation and sorting are essential steps in cell biology research and in many diagnostic and therapeutic methods. Recently, there has been interest in methods which avoid the use of biochemical labels; numerous intrinsic biomarkers have been explored to identify cells including size, electrical polarizability, and hydrodynamic properties. This review highlights microfluidic techniques used for label-free discrimination and fractionation of cell populations. Microfluidic systems have been adopted to precisely handle single cells and interface with other tools for biochemical analysis. We analyzed many of these techniques, detailing their mode of separation, while concentrating on recent developments and evaluating their prospects for application. Furthermore, this was done from a perspective where inertial effects are considered important and general performance metrics were proposed which would ease comparison of reported technologies. Lastly, we assess the current state of these technologies and suggest directions which may make them more accessible

Lead-Time Trajectory of CA19-9 as an Anchor Marker for Pancreatic Cancer Early Detection

Background & Aims There is substantial interest in liquid biopsy approaches for cancer early detection among subjects at risk, using multi-marker panels. CA19-9 is an established circulating biomarker for pancreatic cancer; however, its relevance for pancreatic cancer early detection or for monitoring subjects at risk has not been established. Methods CA19-9 levels were assessed in blinded sera from 175 subjects collected up to 5 years before diagnosis of pancreatic cancer and from 875 matched controls from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. For comparison of performance, CA19-9 was assayed in blinded independent sets of samples collected at diagnosis from 129 subjects with resectable pancreatic cancer and 275 controls (100 healthy subjects; 50 with chronic pancreatitis; and 125 with noncancerous pancreatic cysts). The complementary value of 2 additional protein markers, TIMP1 and LRG1, was determined. Results In the PLCO cohort, levels of CA19-9 increased exponentially starting at 2 years before diagnosis with sensitivities reaching 60% at 99% specificity within 0 to 6 months before diagnosis for all cases and 50% at 99% specificity for cases diagnosed with early-stage disease. Performance was comparable for distinguishing newly diagnosed cases with resectable pancreatic cancer from healthy controls (64% sensitivity at 99% specificity). Comparison of resectable pancreatic cancer cases to subjects with chronic pancreatitis yielded 46% sensitivity at 99% specificity and for subjects with noncancerous cysts, 30% sensitivity at 99% specificity. For prediagnostic cases below cutoff value for CA19-9, the combination with LRG1 and TIMP1 yielded an increment of 13.2% in sensitivity at 99% specificity ( P = .031) in identifying cases diagnosed within 1 year of blood collection. Conclusion CA19-9 can serve as an anchor marker for pancreatic cancer early detection applications