In this paper we discuss the transformation of a sheet of material into a wide range of desired shapes and patterns by introducing a set of simple cuts in a multilevel hierarchy with different ...motifs. Each choice of hierarchical cut motif and cut level allows the material to expand into a unique structure with a unique set of properties. We can reverse-engineer the desired expanded geometries to find the requisite cut pattern to produce it without changing the physical properties of the initial material. The concept was experimentally realized and applied to create an electrode that expands to >800% the original area with only very minor stretching of the underlying material. The generality of our approach greatly expands the design space for materials so that they can be tuned for diverse applications.
The development of a cost-effective and efficient bacterial detection assay is essential for diagnostic fields, particularly in resource-poor settings. Although antibodies have been widely used for ...bacterial capture, the production of soluble antibodies is still expensive and time-consuming. Here, we developed a nitrocellulose-based lateral flow assay using cell wall binding domains (CBDs) from phage as a recognition element and colloidal gold nanoparticles as a colorimetric signal for the detection of a model pathogenic bacterium, Bacillus cereus (B. cereus). To improve conjugation efficiency and detection sensitivity, cysteine-glutathione-S-transferase-tagged CBDs and maltose-binding protein-tagged CBDs were produced in Escherichia coli (E. coli) and incorporated in our assays. The sensitivity of the strip to detect B. cereus was 1×104 CFU/mL and the overall assay time was 20min. The assay showed superior results compared to the antibody-based approach, and did not show any significant cross-reactivity. This proof of concept study indicates that the lateral flow assay using engineered CBDs hold considerable promise as simple, rapid, and cost-effective biosensors for whole cell detection.
•The cell wall binding domain (CBD) of endolysin was tested for whole cell detection.•A lateral flow assay using CBD as a recognition element was developed.•The assay showed promising results for whole cell detection.
This paper presents a rotary device designed for facile delivery of multiple reagents to a paper strip for multistep assays. Its purpose is to allow users to easily perform multistep assays and ...achieve sensitive detection. While the test strip remains stationary, rotating the top piece of the device aligns the reagent and absorbent pads to each end of the paper strip and initiates fluid flow. Further incremental rotation makes an adjacent pair of pads to align simultaneously, causing fluid flow of subsequent reagent that was preloaded in the reagent pad. In this work, various porous substrates were tested to observe their effect on overall flow rate of the system and multistep assays were performed to demonstrate its simple use. As a proof of concept, enzyme-linked immunosorbent assay was carried out to detect Escherichia coli O157:H7.
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Measurement of contact angle is important in many areas of science and engineering research. Contact angle analyzers are however not easily accessible due to their expensive cost, ...which hinders their use in research and also in education. In this study we propose a low-cost contact angle analyzer that can be assembled with 3D printed parts. Mobile phone is used for imaging, and the image is analyzed using an open-source ImageJ plugin. Commercial camera tripods are used as platform that provides movement in many degrees of freedom, which are important in leveling of the substrate and proper imaging of droplets. We utilize the tripods to build imaging modules, sample plate module and volume metering module, each of which perform distinct tasks. Especially, we characterize the usefulness of the volume metering module, which helps users dispense same volume of liquid to reduce human error during measurement. The cost of an analyzer is $255.10, which is an order of magnitude lower compared to commercial products. With the advancement in open source software and upgrades in the hardware modules, we expect that the proposed contact angle analyzer to have a positive impact in resource limited research labs and educational environments.
We report a contraction-expansion array (CEA) microchannel device that performs label-free high-throughput separation of cancer cells from whole blood at low Reynolds number (Re). The CEA ...microfluidic device utilizes hydrodynamic field effect for cancer cell separation, two kinds of inertial effects: (1) inertial lift force and (2) Dean flow, which results in label-free size-based separation with high throughput. To avoid cell damages potentially caused by high shear stress in conventional inertial separation techniques, the CEA microfluidic device isolates the cells with low operational Re, maintaining high-throughput separation, using nondiluted whole blood samples (hematocrit ~45%). We characterized inertial particle migration and investigated the migration of blood cells and various cancer cells (MCF-7, SK-BR-3, and HCC70) in the CEA microchannel. The separation of cancer cells from whole blood was demonstrated with a cancer cell recovery rate of 99.1%, a blood cell rejection ratio of 88.9%, and a throughput of 1.1 × 10(8) cells/min. In addition, the blood cell rejection ratio was further improved to 97.3% by a two-step filtration process with two devices connected in series.
Selective cyclooxygenase-2 inhibitors (celecoxib) can minimize the gastrointestinal complications related to non-steroidal anti-inflammatory drug (NSAID) use. NAXOZOL is a new combination formulation ...designed to provide sequential delivery of a non-enteric-coated, immediate-release esomeprazole strontium tetrahydrate 20 mg mantle followed by an enteric-coated naproxen 500 mg core. However, there have been no studies comparing NAXOZOL to celecoxib with respect to gastrointestinal tract protection and pain relief in patients with osteoarthritis. This study was undertaken to compare the effects of NAXOZOL and celecoxib with respect to gastrointestinal tract protection and pain relief in patients with osteoarthritis.
The randomized enrolled patients were divided into two treatment groups: a NAXOZOL group and a celecoxib group. All participants received treatments (NAXOZOL, 500/20 mg (naproxen 500 mg, esomeprazole strontium tetrahydrate 20 mg) twice per day versus celecoxib, 200 mg daily) on a 1:1 allocation basis for 12 weeks. The primary outcome was the Leeds Dyspepsia Questionnaire (LDQ) score used for non-inferiority testing. Secondary outcome measures included the Gastrointestinal Symptom Rating Scale (GSRS) score, Visual Analogue Scale (VAS) score, European Quality of Life-5 dimensions (EQ-5D) scale and the EQ-5D Visual Analogue Scale (EQ VAS). Other outcome measures included the use of supplementary or rescue drugs, and the incidence of adverse events.
The baseline-adjusted LDQ scores immediately after 12 weeks of treatment in NAXOZOL group were not inferior to those in celecoxib group. The overall change in the baseline-adjusted GSRS score, VAS score, EQ-5D, and EQ VAS was not different between the two groups. The usage of supplementary drugs and the drug-related incidence of adverse events were not different. However, the days to use rescue drug were longer in celecoxib group than in NAXOZOL group.
NAXOZOL was not inferior to celecoxib in protecting the gastrointestinal tract and providing pain relief in patients with osteoarthritis.
Anthocyanins have multiple health benefits. However, they are prone to degradation during gastrointestinal digestion, impeding their utilization. Various encapsulation systems have been proposed to ...improve their bioaccessibility and bioavailability. This review aims to provide a systematic evaluation and meta-analysis of published studies examining the effect of microencapsulation on the bioaccessibility of anthocyanins. A comprehensive and systematic literature search of three databases (Scopus, PubMed, and Web of Science) was conducted. Studies were selected according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria and were reviewed independently by two investigators. Overall, 34 articles were included in the systematic review and 24 were included in the meta-analysis. The fold changes in bioaccessibility between encapsulated and non-encapsulated anthocyanins from eligible studies were calculated. The median and 95% confidence intervals (CI) of the fold changes for spray-drying (median 1.23, 95% CI 0.91-1.92), freeze-drying (median 1.19, 95% CI 0.61-1.28), simple coacervation (median 1.80, 95% CI 1.41-3.20), and complex coacervation (median 1.61, 95% CI 0.21-25.00) were calculated. Simple coacervation showed a promising protection against degradation during
digestion. However, when a large number of anthocyanins cannot be released from the microparticles during digestion, encapsulation impedes the bioaccessibility of anthocyanins.
Continuous monitoring of intraocular pressure, particularly during sleep, remains a grand challenge in glaucoma care. Here we introduce a class of smart soft contact lenses, enabling the continuous ...24-hour monitoring of intraocular pressure, even during sleep. Uniquely, the smart soft contact lenses are built upon various commercial brands of soft contact lenses without altering their intrinsic properties such as lens power, biocompatibility, softness, transparency, wettability, oxygen transmissibility, and overnight wearability. We show that the smart soft contact lenses can seamlessly fit across different corneal curvatures and thicknesses in human eyes and therefore accurately measure absolute intraocular pressure under ambulatory conditions. We perform a comprehensive set of in vivo evaluations in rabbit, dog, and human eyes from normal to hypertension to confirm the superior measurement accuracy, within-subject repeatability, and user comfort of the smart soft contact lenses beyond current wearable ocular tonometers. We envision that the smart soft contact lenses will be effective in glaucoma care.
Despite similar brachial blood pressure, central hemodynamics could be different. The objective of the present study was to investigate the factors, which could influence the discrepancy between ...central BP (cBP) and brachial blood pressure. Six hundred forty-seven patients (364 males, 48 ± 12 years old) were enrolled. Using applanation tonometry, cBP was noninvasively derived. The median difference between brachial systolic BP (bSBP) and central systolic BP (cSBP) was 8 mm Hg. We defined the discrepancy between bSBP and cSBP as differences >8 mm Hg. For adjustment of cBP, population was divided into 3 groups according to the cBP: group 1, <140 mm Hg of cSBP; group 2, 140 > cSBP < 160 mm Hg; group 3, =160 mm Hg of cSBP. All the central hemodynamic parameters of the patients, including augmentation pressure, augmentation index (AI), heart rate (75 bpm) adjusted augmentation index (AI@HR75), and subendocardial viability ratio, were measured. Using multivariate logistic regression analysis, we evaluated the factors which could influence the discrepancy between bSBP and cSBP. Age, gender, augmentation pressure, AI, and AI@HR75 were correlated with the discrepancy between bSBP and cSBP. AI@HR75 was significantly correlated with the discrepancy between bSBP and cSBP (β-coefficient = -0.376, P < .001 in group 1; β-coefficient = -0.297, P < .001 in group 2; and β-coefficient = -0.545, P < .001 in group 3). In groups 1 and 2, male gender was significantly correlated with the discrepancy between bSBP and cSBP (β-coefficient = -0.857, P = .035 in group 1; β-coefficient = -1.422, P = .039 in group 2). In present study, arterial stiffness might affect the discrepancy between bSBP and cSBP. Also, male gender was closely related to the discrepancy between bSBP and cSBP especially with cSBP <160 mm Hg. Not only cSBP, the discrepancy between cSBP and bSBP should be considered for understanding the central hemodynamics.
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We present a low cost, 3D printed open-source antibody dispenser that can be easily built and used for the development of lateral flow assay (LFA) strips. The fabrication of LFA ...strips need dispensing of antibodies or antigens in a linear fashion and commercially available dispensers typically cost from few thousands to few tens of thousands of US dollars. In this paper, an antibody dispenser was built by using 3D printed and commercially available parts, which cost no more than 30 USD. This paper presents a detailed instruction on how to assemble the printer and how to achieve a specific line width for the dispensed antibody. By using syringe needles of different gauges, line width ranging from 0.23 to 1.8 mm can be dispensed, and by varying the speed controller, the dispensing needle’s speed can be varied between 2.8 and 3.8 cm/s. We demonstrate uniform dispensing of anti-C-reactive protein (CRP) antibody and anti-rabbit antibody to draw a test line and a control line, which are used for the detection of CRP. The dispenser can also be equipped with two dispensing needles to allow simultaneous dispensing of multiple reagents, which can be useful for LFA strip development.
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