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Hypoxia is a nonphysiological oxygen tension which is common in most malignant tumors. Hypoxia stimulates complicated cell signaling networks in cancer cells, e.g., the HIF, PI3K, MAPK, and NFκB pathways. Then, cells release a number of cytokines such as VEGFA to promote the growth of peripheral blood vessels and lead to metastasis. In the current work, understanding of the internal hypoxic environment in solid tumor tissue was attempted by developing a folding paper system. A paper-based solid tumor was constructed by folding a filter paper cultured with cancer cells. The cellular response in each layer could be analyzed by disassembling the folded paper after the culture course. The result showed that an internal hypoxic environment was successfully reproduced in the paper-based solid tumor. The cells in the inner layer expressed high levels of HIF1-α and VEGFA. Hence, proliferation and migration of endothelial cells were shown to be induced by the cells located in the internal hypoxic environment. Moreover, the paper-based solid tumor was transplanted into nude mice for the study of hypoxic response and angiogenesis. The crosstalk between internal and external parts of solid tumor tissue could be analyzed by sectioning each layer of the paper-based solid tumor. This approach provides a favorable analytical method for the discovery of the interaction between cancer cells, hypoxia, and peripheral angiogenesis.

An industry compatible chemo-refining approach was tested for preparation of micro-nanofibrillated cellulose (MNFC) from bleached softwood pulp using sodium meta-periodate and sodium chlorite as oxidizers followed by refining in Valley beater. SEM and FTIR analyses confirmed micro-nano scale fibrillation and chemical functional group modification in laboratory prepared MNFC, respectively. The water retention value, carboxyl content and viscosity of MNFC were found comparable with imported NFC as reference (R-NFC). To evaluate MNFC as strength enhancer for paper properties, 5% MNFC addition to bleached mixed hardwood pulp showed 6% reduction in bulk with 36%, 24% and 97% increment in breaking length, burst index and double fold of the handsheets, respectively without affecting tear index and optical properties than the control. Surface properties were also improved. Pulp drainability (37°SR) after MNFC addition was found suitable for papermaking. These laboratory results confirmed the potential of MNFC as a suitable strength additive for paper quality improvement.

The study describes the preparation of pulp and nanocellulose from non-wood plant materials, as well as an improved properties of paper and cardboard for mass production. The pulps from wheat straw, kenaf and flax fibers were prepared by the environmentally friendly organosolv method—cooking in a solution of isobutanol or peracetic acid. The organosolv pulps used to prepare nanocellulose had traces of lignin and mineral substances. The process of hydrolysis of the investigated organosolv pulps was optimal when carried out under the following conditions: 43% sulfuric acid, temperature 60 °C, hydrolysis time 90 min and ultrasonic treatment 60 min. Using the methods of SEM, XRD, TEM, AFM and TGA, the structure and properties of organosolv pulps and nanocellulose were studied. The use of nanocellulose in bulk and on the surface of mass types of paper and cardboard—paper for corrugation, offset paper, recycled containerboard and cardboard for flat layers of corrugated cardboard were investigated. We established the positive effect of nanocellulose application on the physical and mechanical properties of paper and cardboard. Low consumption of nanocellulose allows production of the paper and cardboard with properties that meet the requirements to appropriate standards and replacement of synthetic reinforcing materials.

The present review provides a comprehensive outlook toward the possibilities of developing a functional in vitro liver tissue model on a paper platform. To this end, we first addressed the suitabil...

RNA can fold back on itself to adopt a wide range of structures. These range from relatively simple hairpins to intricate 3D folds and can be accompanied by regulatory interactions with both metabolites and macromolecules. The last 50 yr have witnessed elucidation of an astonishing array of RNA structures including transfer RNAs, ribozymes, riboswitches, the ribosome, the spliceosome, and most recently entire RNA structuromes. These advances in RNA structural biology have deepened insight into fundamental biological processes including gene editing, transcription, translation, and structure-based detection and response to temperature and other environmental signals. These discoveries reveal that RNA can be relatively static, like a rock; that it can have catalytic functions of cutting bonds, like scissors; and that it can adopt myriad functional shapes, like paper. We relate these extraordinary discoveries in the biology of RNA structure to the plant way of life. We trace plant-specific discovery of ribozymes and riboswitches, alternative splicing, organellar ribosomes, thermometers, whole-transcriptome structuromes and pan-structuromes, and conclude that plants have a special set of RNA structures that confer unique types of gene regulation. We finish with a consideration of future directions for the RNA structure–function field.

Paper-based works of art and documents of cultural importance kept in museums and libraries can show notorious signs of deterioration, including foxing stains, caused by fungal colonization. Some of the main chromophore agents of fungal origin that deteriorate paper and therefore affect paper cultural heritage both aesthetically and structurally are the group of pigments called melanins. Thus, knowledge of the diversity and features of fungal melanins and of the melanization pathways of fungi growing on paper is key to removing these pigments from paper-based works of cultural importance. This review provides an approach about the current knowledge of melanins synthesized by paper-colonizing fungi, their localization in the fungal structures, and their role in the deterioration of paper. This knowledge might contribute to developing new, effective, and sustainable strategies of restoration and conservation of historical documents and works of art based on paper.

A superhydrophobic paper with excellent robustness was fabricated by roll coating with modified nano-TiO2. First, nano-TiO2 particles were hydrophobically modified by γ-aminopropyltriethoxysilane and 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (POTS). Then the paper coating composed of modified nano-TiO2 particles as pigments and epoxy resin (EP) as adhesives was coated on a paper surface to create the desired surface morphology and surface energy. Compared with the uncoated filter paper, the prepared paper showed an improved rough surface morphology owing to the uniform layer of TiO2 microclusters deposited on the fiber network. The superhydrophobic paper exhibited water contact angles (WCA) about 153° ± 1.5°, and water sliding angles (WSA) about 3.5° ± 0.5°, low surface adhesion and excellent bounce ability. The superhydrophobic paper can withstand a variety of wear and tear, such as tape stripping and knife scraping. The as-prepared superhydrophobic paper showed mechanical durability even after 20 wear cycles with sandpaper,thus sustaining excellent superhydrophobicity on the filter paper surface. Moreover, it remains fully functional even in environments with high concentrations of acid and alkali for 96 h. The superhydrophobicity was not affected after storage for 6 months in a natural environment. It was confirmed that the superhydrophobic paper surface exhibited excellent chemical stability, long-term stability and self-cleaning properties. The entire production process was operated under normal environment, without complex equipment; and, as such, has the possibility for large-scale production and application in industry.

This review paper focuses on the gender disparity and causes of gender inequality and sheds light on the important studies on the topic. It also sheds light on the pay parity and performance literature. This review paper also sheds light on the definition, conceptualization, and measurement of employee performance. This review paper has also shown a number of studies that linked the relationship between pay fairness, organizational justice and employee performance. This review paper summarizes these findings and suggests areas where more inquiry is needed to resolve conflicting results. Around more than 50 papers have been studies out of which 12 studies and few blogs and articles are taken into consideration which provides enough evidence to justify that Gender Inequality, Pay Parity could affect Corporate Performance.

This white paper was developed to provide leukapheresis guidance for the collection of mononuclear cells from adult and pediatric patients who are destined for immune effector cell (IEC) therapies for commercial and research applications. Currently, there is considerable variability in leukapheresis processes and limited published information regarding best practices relevant to new cellular therapies, especially IECs. Herein the authors address critical leukapheresis questions in five domains to help guide consistent collection processes and ensure high-quality products. The first four domains are onboarding, pre-collection, collection and post-collection, with protocol feasibility, preparation, care and follow-up of the patient/donor at each step, respectively, and technical considerations during collection. The fifth domain of quality assurance focuses on ensuring product potency, purity, safety and auditing.The American Society for Apheresis (ASFA) Clinical Applications Committee (IEC Therapy Subcommittee) was charged by the society's board of directors with working collaboratively with other ASFA committees and organizations, including the Foundation for the Accreditation of Cellular Therapy, Association for the Advancement of Blood and Biotherapies, American Society for Transplantation and Cellular Therapy, National Marrow Donor Program and International Society for CellGene Therapy, to develop guidelines regarding leukapheresis collection of cells destined for the manufacture of IEC therapies. After a review of the literature and discussion with members of the involved committees and various institutions, a draft guidance was created and circulated for comment and revision.Critical aspects of apheresis that could affect the quality and quantity of the leukapheresis product were identified. These areas were then discussed and reviewed. After consensus, the best practice guidelines were proposed and accepted.In the current era of rapid growth of IEC therapies, it is important to address critical leukapheresis steps to provide high-quality products and more consistent practices and to eliminate redundant efforts.

This paper reports the development of fluorescent-linked immunosorbent paper-based assay for exosome detection. The paper-based device was fabricated with sandwich lamination for easy handling and was coated with exosome-specific antibody as a biosensing platform to detect exosome sample from the cell culture media. This assay employed fluorescent detection which is followed by tagging fluorophore-conjugated detecting antibody on exosome samples. The fluorescent readout was evaluated and quantified from image processing software. This assay can detect high concentration of exosome samples (~ 1010 exosome/mL). However, this assay has encountered various challenges. First, the exosome concentration prepared from cell culture media from cancer-derived ovarian and mesothelial cell lines may be insufficient to reach detectable range. Second, chemical contamination from exosome isolation kits may affect assay sensitivity. Therefore, assay optimization and minimizing chemical contamination are required which could enhance assay specificity and sensitivity.

Urine is commonly used for clinical diagnosis and biomedical research. The discovery of extracellular vesicles (EV) in urine opened a new fast-growing scientific field. In the last decade urinary extracellular vesicles (uEVs) were shown to mirror molecular processes as well as physiological and pathological conditions in kidney, urothelial and prostate tissue. Therefore, several methods to isolate and characterize uEVs have been developed. However, methodological aspects of EV separation and analysis, including normalization of results, need further optimization and standardization to foster scientific advances in uEV research and a subsequent successful translation into clinical practice. This position paper is written by the Urine Task Force of the Rigor and Standardization Subcommittee of ISEV consisting of nephrologists, urologists, cardiologists and biologists with active experience in uEV research. Our aim is to present the state of the art and identify challenges and gaps in current uEV-based analyses for clinical applications. Finally, recommendations for improved rigor, reproducibility and interoperability in uEV research are provided in order to facilitate advances in the field. ESM-U, CG, GV, GJ, IVB, MvR, and VvS, are members of the “IMMPROVE” consortium (Innovative Measurements and Markers for Prostate Cancer Diagnosis and Prognosis using Extracellular Vesicles), which is sponsored by an Alpe d'HuZes grant of the Dutch Cancer Society (grant #EMCR2015-8022). AL is supported by Norges Forskningsråd, Kreftforeningen and Helse Sør-Øst RHF (NO). UE is supported by the NIH, National Heart, Lung, and Blood Institute, Award number K23-HL-126101. CJB and EJH are supported by the Dutch Kidney Foundation (Nierstichting), Award number: CP18.05.

Cellular movement is essential in the formation and maintenance of healthy tissues as well as in disease progression such as tumor metastasis. In this work, we describe a paper-based Transwell assay capable of quantifying cellular invasion through an extracellular matrix. The paper-based Transwell assays generate similar datasets, with equivalent reproducibility, to commercially available Transwell assays. With different culture configurations, we quantify invasion: upon addition of an exogenous factor or in the presence of medium obtained from other cell types, in an indirect or direct co-culture format whose medium composition is dynamically changing, and in a single-zone or parallel (96-zone) format.

Background Brucellosis, as a serious zoonotic infectious disease, has been recognized as a re-emerging disease in the developing countries worldwide. In china, the incidence of brucellosis is increasing each year, seriously threatening the health of humans as well as animal populations. Despite a quite number of diagnostic methods currently being used for brucellosis, innovative technologies are still needed for its rapid and accurate diagnosis, especially in area where traditional diagnostic is unavailable. Methodology/Principal findings In this study, a total of 22 B cell linear epitopes were predicted from five Brucella outer membrane proteins (OMPs) using an immunoinformatic approach. These epitopes were then chemically synthesized, and with the method of indirect ELISA (iELISA), each of them displayed a certain degree of capability in identifying human brucellosis positive sera. Subsequently, a fusion protein consisting of the 22 predicted epitopes was prokaryotically expressed and used as diagnostic antigen in a newly established brucellosis testing method, nano-ZnO modified paper-based ELISA (nano-p-ELISA). According to the verifying test using a collection of sera collected from brucellosis and non-brucellosis patients, the sensitivity and specificity of multiepitope based nano-p-ELISA were 92.38% and 98.35% respectively. The positive predictive value was 98.26% and the negative predictive value was 91.67%. The multiepitope based fusion protein also displayed significantly higher specificity than Brucella lipopolysaccharide (LPS) antigen. Conclusions B cell epitopes are important candidates for serologically testing brucellosis. Multiepitope fusion protein based nano-p-ELISA displayed significantly sensitivity and specificity compared to Brucella LPS antigen. The strategy applied in this study will be helpful to develop rapid and accurate diagnostic method for brucellosis in human as well as animal populations., Author summary Brucellosis is one of the most important zoonosis in the world and has caused tremendous economic losses in agriculture and animal husbandry in many countries. Developing rapid, sensitive and specific diagnostic methods is very important for early detection and treatment of brucellosis patients. In this study, a novel diagnostic technique, nano-ZnO modified paper ELISA, was established. The antigen used in this technique was a fusion protein containing multiple B cell epitopes, which were predicted from Brucella major outer membrane proteins such as Bp26, Omp31, Omp16, Omp2b and Omp25. Comparing to traditional LPS antigen, this multiepitope based antigen displayed considerably higher sensitivity and higher specificity in laboratory. With the strategy described in this paper, more efficient epitopes and protein antigen can be identified in the future. Currently, LPS antigen is only prepared from live Brucella, while protein antigen can be produced in large quantities in prokaryotic expression system. In addition to nano-p-ELISA, this protein antigen can also be used for development other methods such as fluorescent polarization assay (FPA) and immunochromatographic assay (ICA) to meet the varied demand for brucellosis testing.

Mas-related G-protein-coupled receptor X2 (MRGPRX2) has recently been reported to be associated with anaphylaxis. Detection of MRGPRX2 levels in human peripheral blood might serve as a powerful tool for predicting the predisposition of patients to anaphylactic reactions. For rapid measurement of MRGPRX2, we established a paper-based double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) using mouse monoclonal antibody and horseradish peroxidase (HRP)-labelled rabbit polyclonal antibody as capture antibody and detection antibody, respectively. We avoided chemical functionalization of the cellulose paper by introducing bovine serum albumin (BSA) to provide COOH and NH2 groups for covalent immobilization of the capture antibody. Through amide condensation, a two-layer immobilization strategy was applied with BSA-BSA and BSA-capture antibody networks as the first and second layers, respectively. This strategy improved the quantity, activity and stability of the immobilized antibody. We then established a paper-based ELISA to detect MRGPRX2 in human peripheral blood. Our method is less laborious, easier to implement, and more cost-effective than conventional ELISA, while offering similar sensitivity, specificity, and accuracy. Therefore, it could serve as an innovative clinical point-of-care diagnostic tool, especially in areas that lack advanced clinical equipment.

Fungi have the ability to transform organic materials into a rich and diverse set of useful products and provide distinct opportunities for tackling the urgent challenges before all humans. Fungal biotechnology can advance the transition from our petroleum-based economy into a bio-based circular economy and has the ability to sustainably produce resilient sources of food, feed, chemicals, fuels, textiles, and materials for construction, automotive and transportation industries, for furniture and beyond. Fungal biotechnology offers solutions for securing, stabilizing and enhancing the food supply for a growing human population, while simultaneously lowering greenhouse gas emissions. Fungal biotechnology has, thus, the potential to make a significant contribution to climate change mitigation and meeting the United Nation’s sustainable development goals through the rational improvement of new and established fungal cell factories. The White Paper presented here is the result of the 2nd Think Tank meeting held by the EUROFUNG consortium in Berlin in October 2019. This paper highlights discussions on current opportunities and research challenges in fungal biotechnology and aims to inform scientists, educators, the general public, industrial stakeholders and policymakers about the current fungal biotech revolution.

Morbidity and mortality from ischaemic heart disease (IHD) and heart failure (HF) remain significant in Europe and are increasing worldwide. Patients with IHD or HF might benefit from novel therapeutic strategies, such as cell-based therapies. We recently discussed the therapeutic potential of cell-based therapies and provided recommendations on how to improve the therapeutic translation of these novel strategies for effective cardiac regeneration and repair. Despite major advances in optimizing these strategies with respect to cell source and delivery method, the clinical outcome of cell-based therapy remains unsatisfactory. Major obstacles are the low engraftment and survival rate of transplanted cells in the harmful microenvironment of the host tissue, and the paucity or even lack of endogenous cells with repair capacity. Therefore, new ways of delivering cells and their derivatives are required in order to empower cell-based cardiac repair and regeneration in patients with IHD or HF. Strategies using tissue engineering (TE) combine cells with matrix materials to enhance cell retention or cell delivery in the transplanted area, and have recently received much attention for this purpose. Here, we summarize knowledge on novel approaches emerging from the TE scenario. In particular, we will discuss how combinations of cell/bio-materials (e.g. hydrogels, cell sheets, prefabricated matrices, microspheres, and injectable matrices) combinations might enhance cell retention or cell delivery in the transplantation areas, thereby increase the success rate of cell therapies for IHD and HF. We will not focus on the use of classical engineering approaches, employing fully synthetic materials, because of their unsatisfactory material properties which render them not clinically applicable. The overall aim of this Position Paper from the ESC Working Group Cellular Biology of the Heart is to provide recommendations on how to proceed in research with these novel TE strategies combined with cell-based therapies to boost cardiac repair in the clinical settings of IHD and HF. © Published on behalf of the European Society of Cardiology. All rights reserved.

The engineering of advanced materials capable of mimicking the cellular micro-environment while providing cells with physicochemical cues is central for cell culture applications. In this regard, paper meets key requirements in terms of biocompatibility, hydrophilicity, porosity, mechanical strength, ease of physicochemical modifications, cost, and ease of large-scale production, to be used as a scaffold material for biomedical applications. Most notably, paper has demonstrated the potential to become an attractive alternative to conventional biomaterials for creating two-dimensional (2D) and three-dimensional (3D) biomimetic cell culture models that mimic the features of in vivo tissue environments for improving our understanding of cell behavior (e.g. growth, cell migration, proliferation, differentiation and tumor metastasis) in their natural state. On the other hand, integration of plasmonic nanomaterials (e.g. gold nanoparticles) within the fibrous structure of paper opens the possibility to generate multifunctional scaffolds equipped with biosensing tools for monitoring different cell cues through physicochemical signals. Among different plasmonic based detection techniques, surface-enhanced Raman scattering (SERS) spectroscopy emerged as a highly specific and sensitive optical tool for its extraordinary sensitivity and the ability for multidimensional and accurate molecular identification. Thus, paper-based plasmonic substrates in combination with SERS optical detection represent a powerful future platform for monitoring cell cues during cell culture processes. To this end, in this review, we will describe the different methods for fabricating hybrid paper-plasmonic nanoparticle substrates and their use in combination with SERS spectroscopy for biosensing and, more specifically, in cell culture applications., Graphical abstract Image 1

Companies are turning to social media marketing as the newest means of promoting their products and services. Instagram, a photo-sharing app for mobile devices, has emerged as a critical marketing tool. This research aims to determine which of the three Instagram marketing strategies is the most effective in terms of growing a following, increasing brand recognition, and boosting sales. Many secondary sources were also used to support the primary research. Instagram users in the city of Ahmedabad were surveyed to gather information. T-tests, Chi-Square, and descriptive statistics were used to examine the data further. A recent study found that Instagram users take a variety of things into account when deciding whether or not to follow a brand or post about a product or service. According to our survey, the vast majority of those who responded were utilizing Instagram to promote their brands and increase sales on their e-commerce sites. Generally, Instagram users create traffic by arranging their grids attractively, publishing consistently, following Instagram trends, and offering discounts and coupons. Marketers may use Instagram to their advantage by creating unique and engaging content. Because of Instagram's emphasis on visual features such as photographs and videos, marketers now have a new channel through which to reach customers. Customers and businesses may converse more easily and casually on Instagram because of the platform's more relaxed atmosphere.

Background: In recent years, there has been an increasing interest in using extracellular vesicles (EVs) as potential therapeutic agents or natural drug delivery systems in kidney-related diseases. However, a detailed and targeted report on the current condition of extracellular vesicle research in kidney-related diseases is lacking. Therefore, this prospective study was designed to investigate the use of bibliometric analysis to comprehensively overview the current state of research and frontier trends on extracellular vesicle research in kidney-related diseases using visualization tools.Methods: The Web of Science Core Collection (WoSCC) database was searched to identify publications related to extracellular vesicle research in kidney-related diseases since 1999. Citespace, Microsoft Excel 2019, VOSviewer software, the R Bibliometrix Package, and an online platform were used to analyze related research trends to stratify the publication data and collaborations.Results: From 1 January 1999 to 26 June 2022, a total of 1,122 EV-related articles and reviews were published, and 6,486 authors from 1,432 institutions in 63 countries or regions investigated the role of extracellular vesicles in kidney-related diseases. We found that the number of articles on extracellular vesicles in kidney-related diseases increased every year. Dozens of publications were from China and the United States. China had the most number of related publications, in which the Southeast University (China) was the most active institution in all EV-related fields. Liu Bi-cheng published the most papers on extracellular vesicles, while Clotilde Théry had the most number of co-citations. Most papers were published by The International Journal of Molecular Sciences, while Kidney International was the most co-cited journal for extracellular vesicles. We found that exosome-related keywords included exosome, exosm, expression, extracellular vesicle, microRNA, microvesicle, and liquid biopsy, while disease- and pathological-related keywords included biomarker, microRNA, apoptosis, mechanism, systemic lupus erythematosus, EGFR, acute kidney injury, and chronic kidney disease. Acute kidney disease (AKI), CKD, SLE, exosome, liquid biopsy, and extracellular vesicle were the hotspot in extracellular vesicle and kidney-related diseases research.Conclusion: The field of extracellular vesicles in kidney-related disease research is rapidly growing, and its domain is likely to expand in the next decade. The findings from this comprehensive analysis of extracellular vesicles in kidney-related disease research could help investigators to set new diagnostic, therapeutic, and prognostic ideas or methods in kidney-related diseases.

Radiometric assays have widely been used for measuring protein kinase activity for decades. In addition, several non-radiometric kinase assay formats have been developed over the years, including luciferase-based and fluorescence-based assays. However, radiometric assays are still considered as the "gold standard" for protein kinase assays, because of their direct readout, high sensitivity, reproducibility, reliability, and very low background signals. These radiometric assays rely on P81 phosphocellulose paper to capture the phosphorylated substrate and wash out unreacted [γ-32P] ATP. However, recently the production of P81 was discontinued by the manufacturer, causing major concern within the protein kinase research community. The advantages of radiometric assays over other kinase assay methods call for an urgent alternative to the discontinued P81 paper. In this report, we demonstrate that the LSA-50 paper is a worthy alternative for radiometric protein kinase assays originally using P81 phosphocellulose paper. ispartof: ANALYTICAL BIOCHEMISTRY vol:630 ispartof: location:United States status: published

Mercury (Hg2+) and silver (Ag+) ions possess the harmful effects on public health and environment that makes it essential to develop the sensing techniques with great sensitivity for the ions. Metal ions commonly coexist in the different biological and environmental systems. Hence, it is an urgent demand to design a simple method for the simultaneous detection of metal ions, peculiarly in the case of coexisting Hg2+ and Ag+. This study introduces a low-cost paper-based aptasensor to monitor Hg2+ and Ag+, simultaneously. The strategy of the sensing array is according to the conformational changes of Hg2+- and Ag+-specific aptamers and their release from the GO surface after the injection of the target sample on the sensing platform. Through monitoring the fluorescence recovery changes against the concentrations of the ions, Hg2+ and Ag+ can be determined as low as 1.33 and 1.01 pM. The paper-based aptasensor can simultaneously detect the ions within about 10 min. The aptasensor is applied prosperously to monitor Hg2+ and Ag+ in human serum, water, and milk. The designed aptasensor with the main advantages of simplicity and feasibility holds the supreme potential to develop a cost-effective sensing method for environmental monitoring, food control, and human diagnostics.

In this study, levels of inflammatory protein biomarkers in venous plasma, plasma derived from capillary blood from the earlobe, and capillary plasma stored as dried plasma spots (DPS) were compared. Samples from 12 male individuals were assessed with a panel of 92 inflammation-related proteins using multiplex proximity extension assay. Correlations between sample types varied greatly between analytes. A high correlation of rho > 0.8 was observed between capillary plasma and DPS for 32 analytes. At this level of correlation, 13 analytes correlated between venous and capillary plasma and 5 analytes in the comparison of venous blood with DPS.

In this work, cellulose filter paper (CFP), which is inexpensive and commercially available, was used as the carrier, and the immobilized α-glucosidase was obtained by two steps: firstly, the surface of CFP was modified by polydopamine/polyethyleneimine (PDA/PEI) co-deposition method to obtain CFP-PDA/PEI with a uniform coating of rich positive charge; subsequently, α-glucosidase was immobilized on the CFP-PDA/PEI by electrostatic adsorption. The free enzyme and immobilized enzyme have the same optimal temperature (70℃) and pH (8.0), and their Km is similar, which is 2.2 and 2.8, respectively. These results show that the immobilization process does not change the properties of the enzyme greatly. The immobilized enzyme still maintains 75.6% of its initial activity after 10 repeated uses, showing good reusability. The excellent repeatability (RSD = 2.2%, n = 5) and the verification of competitive inhibitor (acarbose) illustrates the reliability of the immobilized enzymes for enzyme inhibitor screening. Finally, combined with CE, a screening method based immobilized α-glucosidase was proposed and applied to screen the α-glucosidase inhibitory from 10 kinds of Traditional Chinese medicines (TCMs) in vitro. The results indicated that the method was a very effective tool for screening potential α-glucosidase inhibitors from TCMs.

Abstract Mechanical stimuli play important roles on the growth, development, and behavior of tissue. A simple and novel paper-based in vitro tissue chip was developed that can deliver two types of mechanical stimuli—local compression and shear flow—in a programmed manner. Rat vascular endothelial cells (RVECs) were patterned on collagen-coated nitrocellulose paper to create a tissue chip. Localized compression and shear flow were introduced by simply tapping and bending the paper chip in a programmed manner, utilizing an inexpensive servo motor controlled by an Arduino microcontroller and powered by batteries. All electrical compartments and a paper-based tissue chip were enclosed in a single 3D-printed enclosure, allowing the whole device to be independently placed within an incubator. This simple device effectively simulated in vivo conditions and induced successful RVEC migration in as early as 5 h. The developed device provides an inexpensive and flexible alternative for delivering mechanical stimuli to other in vitro tissue models. Graphical abstract

Escherichia coli O157: H7 (E. coli O157: H7) has become one of the most dangerous foodborne pathogenic bacteria around the world. Currently, because of the tedious, high-cost and stringent laboratory conditions required, the conventional E. coli O157: H7 detection methods, such as culture-based methods and polymerase chain reaction (PCR), have much limitation. Thus, we developed a novel paper-based enzyme-linked immunosorbent assay (p-ELISA) with shorter operation duration, lower cost, relatively higher sensitivity and wider application. This method required less than 3 h and 5 μL of sample to complete the detection. The limit of detection (LOD) for E. coli O157: H7 reached 1 × 104 CFU/mL with high specificity. To be more suitable for on-site testing, the readout could be rapidly obtained without any expensive instruments. In this study, we chose E. coli O157:H7 as the representative, and our method could provide a platform for determination of other pathogenic bacteria.