Nanozyme-amplified lateral flow immunoassay for molecular signature detection of cardiovascular diseases

Point-of-care (PoC) devices offer the opportunity to decentralize the analysis of biomarkers in biological fluids thus providing patients with more personalized medicine. The golden standard of PoC platforms are lateral flow assays since they are low cost, quick to perform and user-friendly [1]. Here we show the use of a nanozyme-mediated signal readout on a multiplexed PoC lateral flow immunoassay for the diagnosis of cardiovascular diseases. Our aim has been to expand the application of this ultrasensitive detection method towards the development of a multiplexed PoC assay for cardiovascular-related biomarkers to support triage of myocardial injury

Elevated Blood Lead Concentrations and Vitamin D Deficiency in Winter and Summer in Young Urban Children

BACKGROUND: It is widely recognized that blood lead concentrations are higher in the summer than in winter. Although the effects of some environmental factors such as lead in dust on this phenomenon have been studied, relationships to sunlight-induced vitamin D synthesis have not been adequately investigated. Vitamin D status is influenced by the diet, sunlight exposure, age, skin pigmentation, and other factors, and may modify gastrointestinal lead absorption or release of lead stored in bones into the bloodstream. OBJECTIVE AND METHODS: We collected paired blood samples from 142 young, urban African-American and Hispanic children in the winter and summer to study the seasonal increase in blood lead and its relationships to vitamin D nutrition, age, and race. RESULTS: A winter/summer (W/S) increase in blood lead concentrations of 32.4% was found for children 1–3 years of age. There was a smaller W/S increase of 13.0% in children 4–8 years of age. None of the 51 Hispanic children had an elevated blood lead concentration (≥ 10 μg/dL) during the winter, and only one had an elevated summertime concentration. In contrast, elevated blood lead concentrations were frequent in the 91 African-American children, especially those 1–3 years of age. For the latter, the percentage with elevated blood lead levels increased from 12.2% in winter to 22.5% in summer. A 1.2% W/S increase in serum 25-hydroxy-vitamin D (serum 25-OH-D) concentrations was found for children 1–3 years of age. However, in children 4–8 years of age the W/S increase in serum 25-OH-D was much larger—33.6%. The percentages of children with low (< 16 μg/L) serum 25-OH-D concentrations were 12.0% in winter and 0.7% in summer and were consistently greater in African-American than in Hispanic children. The seasonal increases in blood lead and serum 25-OH-D in children 4–8 years of age were significantly associated. CONCLUSION: The higher summertime serum 25-OH-D concentrations for the 4- to 8-year-old children are likely caused by increased sunlight-induced vitamin D synthesis and may contribute to the seasonal increase in blood lead. Age and race are key factors that affect blood lead and vitamin D nutrition, as well as their interactions, in young urban children

Towards Autonomous Robotic Minimally Invasive Ultrasound Scanning and Vessel Reconstruction on Non-Planar Surfaces

Autonomous robotic Ultrasound (US) scanning has been the subject of research for more than 2 decades. However, little work has been done to apply this concept into a minimally invasive setting, in which accurate force sensing is generally not available and robot kinematics are unreliable due to the tendon-driven, compliant robot structure. As a result, the adequate orientation of the probe towards the tissue surface remains unknown and the anatomy reconstructed from scan may become highly inaccurate. In this work we present solutions to both of these challenges: an attitude sensor fusion scheme for improved kinematic sensing and a visual, deep learning based algorithm to establish and maintain contact between the organ surface and the US probe. We further introduce a novel scheme to estimate and orient the probe perpendicular to the center line of a vascular structure. Our approach enables, for the first time, to autonomously scan across a non-planar surface and navigate along an anatomical structure with a robotically guided minimally invasive US probe. Our experiments on a vessel phantom with a convex surface confirm a significant improvement of the reconstructed curved vessel geometry, with our approach strongly reducing the mean positional error and variance. In the future, our approach could help identify vascular structures more effectively and help pave the way towards semi-autonomous assistance during partial hepatectomy and the potential to reduce procedure length and complication rates

Ion beam generated surface ripples: new insight in the underlying mechanism

A new hydrodynamic mechanism is proposed for the ion beam induced surface patterning on solid surfaces. Unlike the standard mechanisms based on the ion beam impact generated erosion and mass redistribution at the free surface (proposed by Bradley-Harper (BH) and its extended theories), the new mechanism proposes that the ion beam induced saltation and creep processes, coupled with incompressible solid flow in amorphous layer, leads to the formation of ripple patterns at the amorphous/crystalline (a/c) interface and hence at the free surface. Ion beam stimulated solid flow inside the amorphous layer controls the wavelength, where as the amount of material transported and re-deposited at a/c interface control the amplitude of ripples. The new approach is verified by designed experiments and supported by the discrete simulation method.Comment: 12 pages, 6 figures. arXiv admin note: substantial text overlap with arXiv:1206.082

Myocardial fibrosis in Eisenmenger syndrome: a descriptive cohort study exploring associations of late gadolinium enhancement with clinical status and survival

BACKGROUND: A relationship between myocardial fibrosis and ventricular dysfunction has been demonstrated using late gadolinium enhancement (LGE) in the pressure-loaded right ventricle from congenital heart defects. In patients with Eisenmenger syndrome (ES), the presence of LGE has not been investigated. The aims of this study were to detect any myocardial fibrosis in ES and describe major clinical variables associated with the finding. METHODS: From 45 subjects screened, 30 subjects (age 43 ± 13 years, 20 female) underwent prospective cardiovascular magnetic resonance with LGE to quantify biventricular volume and function as well as maximal and submaximal exercise during a single visit. Standard cine acquisitions were obtained for ventricular volume and function. Further imaging was performed after administration of 0.1 mmol/kg gadolinium contrast. Regions of LGE were evaluated qualitatively and quantitatively by manual contouring of identified areas, with total area expressed as a percentage of mass. Patients were followed prospectively (mean follow up 7.4 ± 0.4 years) and any deaths recorded. Patients with LGE findings were compared to those without. RESULTS: LGE was present in 22/30 (73%) patients, specifically in RV myocardium (70%), RV trabeculae (60%), LV myocardium (33%) or LV papillary muscles (30%), though in small amounts (mean 1.4% of total ventricular mass, range 0.16 – 6.0%). Those with any LGE were not different in age, history of arrhythmia, desaturation, nor hemoglobin, nor ventricular size, mass, or function. Exercise capacity was low, but also not different between those with and without LGE. Similarly no significant associations were found with amount of fibrosis. There were five deaths among patients with LGE, versus two in patients without, but no difference in survival (log rank =0.03, P = 0.85). CONCLUSIONS: Myocardial fibrosis by LGE is common in ES, though not extensive. The presence and quantity of LGE did not correlate with ventricular size, function, degree of cyanosis, exercise capacity, or survival in this pilot study. More data are clearly required before recommendations for routine use of LGE in these patients can be made

Performance evaluation of different coating materials in delamination for micro-milling applications on high-speed steel substrate.

This is the final version. Available from MDPI via the DOI in this record. The objective of the present work is to carry out analytical and finite element analysis for commonly used coating materials for micro-milling applications on high-speed steel substrate and evaluate the effects of different parameters. Four different coating materials were selected for micro-milling applications: titanium nitride (TiN), diamond-like carbon (DLC), aluminium titanium nitride (AlTiN) and titanium silicon nitride (TiSiN). A 3D finite element model of coating and substrate assembly was developed in Abaqus to find the Hertzian normal stress when subjected to normal load of 4 N, applied with the help of a rigid ball. The radius of the rigid ball was 200 µm. For all the coating materials, the length was 3 mm, the width was 1 mm, and the thickness was 3 µm. For the high-speed steel substrate, the length was 3 mm, the width was 1 mm, and the thickness was 50 µm. Along the length and width, coating and substrate both were divided into 26 equal parts. The deformation behaviour of all the coating materials was considered as linear-elastic and that of the substrate was characterized as elastic-plastic. The maximum normal stress developed in the FEA model was 12,109 MPa. The variation of the FEA result from the analytical result (i.e., 12,435.97 MPa is 2.63%) which is acceptable. This confirms that the FEA model of coating-substrate assembly is acceptable. The results shows that the TiSiN coating shows least plastic equivalent strain in the substrate, which serves the purpose of protecting the substrate from plastic deformation and the TiSiN of 3 micron thickness is the most optimum coating thickness for micro-milling applications

Business models for circular sanitation: lessons from India

Providing safe sanitation in the developing world is still a major hurdle to achieving Sustainable Development Goal number six, with 61% of the global population lacking safely managed sanitation services. Circular economy in the context of sanitation focuses on the whole sanitation chain which includes the provision of toilets, the collection of waste, treatment and transformation into sanitation-derived products including fertiliser, fuel and clean water. As well as potentially reducing the cost of toilet provision, a circular economy approach also has the potential to enable positive environmental and health impacts, unlike other systems where waste may be discharged untreated into the environment. The implementation of a system level transformation is not simple, considering operator capacity, lack of funding, slowly growing acceptance by local communities, and a policy landscape which can be inconsistent in its support for the circular economy. As India invests in long-term infrastructure to improve citizens’ quality of life (e.g., Swachh Bharat Mission), it could incorporate circular economy principles into the design of infrastructure, creating effective urban nutrient and material cycles, enhancing economic development and welfare. This represents a significant opportunity for government and businesses in India to develop circular sanitation infrastructure to recover and valorise biological nutrients. After collecting information from five case studies across India, covering different treatment technologies, waste-derived products, markets and contexts; this research identifies the main barriers and enablers for circular sanitation business models to succeed. Whilst there were many different institutional and technological arrangements, common issues of managing and enforcing incoming waste and competing with chemical fertilisers were found

Trans-visceral migration of retained surgical gauze as a cause of intestinal obstruction: a case report

<p>Abstract</p> <p>Introduction</p> <p>A retained surgical sponge in the abdomen is uncommon although it is likely that this finding is underreported in the medical literature. The intravisceral migration of retained surgical gauze is even rarer, as demonstrated by the very few cases reported.</p> <p>Case presentation</p> <p>Three years after undergoing anterior resection of the rectum, a 75-year-old man presented with symptoms of small bowel obstruction. Plain abdominal radiography and CT showed a radio-opaque marker; a foreign body was suspected, probably a piece of retained surgical gauze. An ileotomy of about 5 cm. was performed to confirm this diagnosis and remove the gauze.</p> <p>Conclusion</p> <p>Although rare, retained gauze in the abdomen is a complication of surgery. The authors consider that this event may be more frequent than it appears from reports in the literature, probably because of its medico-legal implications. If all such cases were reported, it would be possible to estimate their exact number, classify the occurrence as a possible surgical complication and thus modify its medico-forensic consequences.</p

In vitro effects of zinc on the cytokine production from peripheral blood mononuclear cells in patients with zinc allergy.

Metals, such as nickel, cobalt, chromium and zinc, are ubiquitous in the environment. Systemic reactions, including hand dermatitis and generalized eczematous reactions, can be caused by the dietary ingestion of metals. In this study, we aimed to determine whether the cytokine production from peripheral blood mononuclear cells (PBMCs) obtained from zinc allergy patients can be used as a sensitive marker to investigate zinc-allergic contact dermatitis. The diagnosis of sensitivity to metal was made based on the results of a metal patch test. The PBMCs were stimulated with various concentrations (5-100 μM) of zinc sulfate (ZnSO4) for 24 h. The culture supernatants were collected and analyzed using ELISA for measurement of the cytokine production. The levels of IFN-γ, TNF-α, IL-1β, IL-5, IL-13 and MIF were significantly higher in the zinc-allergic patients (n = 5) than in the healthy controls (n = 5) at 100 μM of ZnSO4 stimulation. Although, patch testing is considered as standard test to diagnose metal allergy but false-positive and -negative reactions may limit its use in conditions of existing dermatitis. Therefore, this study suggest that in support of patch testing the determination of cytokine production using PBMCs cultures would be helpful for making an early diagnosis of such conditions

A Minimal Model of Metabolism Based Chemotaxis

Since the pioneering work by Julius Adler in the 1960's, bacterial chemotaxis has been predominantly studied as metabolism-independent. All available simulation models of bacterial chemotaxis endorse this assumption. Recent studies have shown, however, that many metabolism-dependent chemotactic patterns occur in bacteria. We hereby present the simplest artificial protocell model capable of performing metabolism-based chemotaxis. The model serves as a proof of concept to show how even the simplest metabolism can sustain chemotactic patterns of varying sophistication. It also reproduces a set of phenomena that have recently attracted attention on bacterial chemotaxis and provides insights about alternative mechanisms that could instantiate them. We conclude that relaxing the metabolism-independent assumption provides important theoretical advances, forces us to rethink some established pre-conceptions and may help us better understand unexplored and poorly understood aspects of bacterial chemotaxis