65 research outputs found
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Measuring Markers of Liver Function Using a Micropatterned Paper Device Designed for Blood from a Fingerstick
This paper describes a paper-based microfluidic device that measures two enzymatic markers of liver function (alkaline phosphatase, ALP, and aspartate aminotransferase, AST) and total serum protein. A device consists of four components: (i) a top plastic sheet, (ii) a filter membrane, (iii) a patterned paper chip containing the reagents necessary for analysis, and (iv) a bottom plastic sheet. The device performs both the sample preparation (separating blood plasma from erythrocytes) and the assays; it also enables both qualitative and quantitative analysis of data. The data obtained from the paper-microfluidic devices show standard deviations in calibration runs and “spiked” standards that are acceptable for routine clinical use. This device illustrates a type of test useable for a range of assays in resource-poor settings.Chemistry and Chemical Biolog
Engineering estructural defense responses in tomato for resistance against the bacterial wilt
Trabajo presentado en 5th International Symposium on Plant Apoplastic Diffusion Barriers (PADiBA) celebrado en Dundee (Escocia) del 13 al 15 de septiembre de 2022
Multizone Paper Platform for 3D Cell Cultures
In vitro 3D culture is an important model for tissues in
vivo. Cells in different locations of 3D tissues are
physiologically different, because they are exposed to different concentrations
of oxygen, nutrients, and signaling molecules, and to other environmental
factors (temperature, mechanical stress, etc). The majority of high-throughput
assays based on 3D cultures, however, can only detect the
average behavior of cells in the whole 3D construct.
Isolation of cells from specific regions of 3D cultures is possible, but relies
on low-throughput techniques such as tissue sectioning and micromanipulation.
Based on a procedure reported previously (“cells-in-gels-in-paper”
or CiGiP), this paper describes a simple method for culture of arrays of thin
planar sections of tissues, either alone or stacked to create more complex 3D
tissue structures. This procedure starts with sheets of paper patterned with
hydrophobic regions that form 96 hydrophilic zones. Serial spotting of cells
suspended in extracellular matrix (ECM) gel onto the patterned paper creates an
array of 200 micron-thick slabs of ECM gel (supported mechanically by cellulose
fibers) containing cells. Stacking the sheets with zones aligned on top of one
another assembles 96 3D multilayer constructs. De-stacking the layers of the 3D
culture, by peeling apart the sheets of paper, “sections” all 96
cultures at once. It is, thus, simple to isolate 200-micron-thick
cell-containing slabs from each 3D culture in the 96-zone array. Because the 3D
cultures are assembled from multiple layers, the number of cells plated
initially in each layer determines the spatial distribution of cells in the
stacked 3D cultures. This capability made it possible to compare the growth of
3D tumor models of different spatial composition, and to examine the migration
of cells in these structures
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NextGEM: Next-Generation Integrated Sensing and Analytical System for Monitoring and Assessing Radiofrequency Electromagnetic Field Exposure and Health
The evolution of emerging technologies that use Radio Frequency Electromagnetic Field (RF-EMF) has increased the interest of the scientific community and society regarding the possible adverse effects on human health and the environment. This article provides NextGEM's vision to assure safety for EU citizens when employing existing and future EMF-based telecommunication technologies. This is accomplished by generating relevant knowledge that ascertains appropriate prevention and control/actuation actions regarding RF-EMF exposure in residential, public, and occupational settings. Fulfilling this vision, NextGEM commits to the need for a healthy living and working environment under safe RF-EMF exposure conditions that can be trusted by people and be in line with the regulations and laws developed by public authorities. NextGEM provides a framework for generating health-relevant scientific knowledge and data on new scenarios of exposure to RF-EMF in multiple frequency bands and developing and validating tools for evidence-based risk assessment. Finally, NextGEM's Innovation and Knowledge Hub (NIKH) will offer a standardized way for European regulatory authorities and the scientific community to store and assess project outcomes and provide access to findable, accessible, interoperable, and reusable (FAIR) data
Detection of Tuberculosis in HIV-Infected and -Uninfected African Adults Using Whole Blood RNA Expression Signatures: A Case-Control Study
BACKGROUND: A major impediment to tuberculosis control in Africa is the difficulty in diagnosing active tuberculosis (TB), particularly in the context of HIV infection. We hypothesized that a unique host blood RNA transcriptional signature would distinguish TB from other diseases (OD) in HIV-infected and -uninfected patients, and that this could be the basis of a simple diagnostic test. METHODS AND FINDINGS: Adult case-control cohorts were established in South Africa and Malawi of HIV-infected or -uninfected individuals consisting of 584 patients with either TB (confirmed by culture of Mycobacterium tuberculosis [M.TB] from sputum or tissue sample in a patient under investigation for TB), OD (i.e., TB was considered in the differential diagnosis but then excluded), or healthy individuals with latent TB infection (LTBI). Individuals were randomized into training (80%) and test (20%) cohorts. Blood transcriptional profiles were assessed and minimal sets of significantly differentially expressed transcripts distinguishing TB from LTBI and OD were identified in the training cohort. A 27 transcript signature distinguished TB from LTBI and a 44 transcript signature distinguished TB from OD. To evaluate our signatures, we used a novel computational method to calculate a disease risk score (DRS) for each patient. The classification based on this score was first evaluated in the test cohort, and then validated in an independent publically available dataset (GSE19491). In our test cohort, the DRS classified TB from LTBI (sensitivity 95%, 95% CI [87-100]; specificity 90%, 95% CI [80-97]) and TB from OD (sensitivity 93%, 95% CI [83-100]; specificity 88%, 95% CI [74-97]). In the independent validation cohort, TB patients were distinguished both from LTBI individuals (sensitivity 95%, 95% CI [85-100]; specificity 94%, 95% CI [84-100]) and OD patients (sensitivity 100%, 95% CI [100-100]; specificity 96%, 95% CI [93-100]). Limitations of our study include the use of only culture confirmed TB patients, and the potential that TB may have been misdiagnosed in a small proportion of OD patients despite the extensive clinical investigation used to assign each patient to their diagnostic group. CONCLUSIONS: In our study, blood transcriptional signatures distinguished TB from other conditions prevalent in HIV-infected and -uninfected African adults. Our DRS, based on these signatures, could be developed as a test for TB suitable for use in HIV endemic countries. Further evaluation of the performance of the signatures and DRS in prospective populations of patients with symptoms consistent with TB will be needed to define their clinical value under operational conditions. Please see later in the article for the Editors' Summary
Albumin-coated SPIONs: an experimental and theoretical evaluation of protein conformation, binding affinity and competition with serum proteins
The variety of nanoparticles (NPs) used in biological applications is increasing and the study of their interaction with biological media is becoming more important. Proteins are commonly the first biomolecules that NPs encounter when they interact with biological systems either in vitro or in vivo. Among NPs, super-paramagnetic iron oxide nanoparticles (SPIONs) show great promise for medicine. In this work, we study in detail the formation, composition, and structure of a monolayer of bovine serum albumin (BSA) on SPIONs. We determine, both by molecular simulations and experimentally, that ten molecules of BSA form a monolayer around the outside of the SPIONs and their binding strength to the SPIONs is about 3.5 × 10−4 M, ten times higher than the adsorption of fetal bovine serum (FBS) on the same SPIONs. We elucidate a strong electrostatic interaction between BSA and the SPIONs, although the secondary structure of the protein is not affected. We present data that supports the strong binding of the BSA monolayer on SPIONs and the properties of the BSA layer as a protein-resistant coating. We believe that a complete understanding of the behavior and morphology of BSA-SPIONs and how the protein interacts with SPIONs is crucial for improving NP surface design and expanding the potential applications of SPIONs in nanomedicine.The research leading to these results has received funding from; the People Program (Marie Curie Actions) of the EC 7th Framework Program under grant agreement no 303630 and co-funded by the European Social Fund, the Spanish Ministry of Economy MAT2015-64442-R, co-supported by FEDER funds, the Generalitat de Catalunya 2014SGR213, the COST Action MP1202, Severo Ochoa Program (SEV-2015-0496) co-funded by European Social Funds, Ramon y Cajal grant RYC-2010-06082 (AL) and the China Scholarship Council fellowship (SMY, 201206150053). CM thanks the Innovation R&D Programme of the UK National Measurement System. AP-M is a recipient of the Universitat Autònoma de Barcelona-Programa Banco de Santander Fellowship. We acknowledge the support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe
Modulating the mucosal drug delivery efficiency of polymeric nanogels tuning their redox response and surface charge
Mucus is a hydrated, viscoelastic, and adhesive gel that lubricates and protects the body from pathogens; however, its protective function hinders drug/nanomedicine diffusion and treatment efficiency. Therefore, novel drug delivery strategies are required to overcome challenging mucosal barriers. Here, multi-responsive nanogels (NGs) are developed and explored their interaction with mucus. Specific NG features (e.g., surface charge, temperature responsiveness, and redox response) are evaluated in a typical mucus-associated environment (i.e., mucin proteins and high glutathione concentrations). The results demonstrate that biocompatibility and the capacity to deliver a protein through mucosal barriers in different in vitro and in vivo models highlight the importance of specific NG design elements. Disulfide bonds are highlighted as redox-sensitive cross-linkers within the NG structure as critical for drug delivery performance; they function as degradation points that enable NG degradation and subsequent drug release and anchoring points to adhere to mucin, thereby enhancing their residence time at the desired site of action. Additionally, it is confirmed that surface charges impact interactions with mucin; positively charged NGs exhibit improved interactions with mucin compared to negatively charged and neutral NGs. Overall, the findings underline the importance of redox response and surface charge in NG design for reaching efficient mucosal drug delivery
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