A simple device to apply equibiaxial strain to cells cultured on flexible membranes

The biomechanical environment to which cells are exposed is important to their normal growth, development, interaction, and function. Accordingly, there has been much interest in studying the role of biomechanical forces in cell biology and pathophysiology. This has led to the introduction and even commercialization of many experimental devices. Many of the early devices were limited by the heterogeneity of deformation of cells cultivated in different locations of the culture plate membranes and were also attached with complicated technical/electronic efforts resulting in a restriction of the reproducibility of these devices. The objective of this study was to design and build a simple device to allow the application of dose-dependent homogeneous equibiaxial static stretch to cells cultured on flexible silicone membranes to investigate biological and biomedical questions. In addition, cultured neonatal rat atrial cardiomyocytes were stretched with the proposed device with different strain gradients. For the first time with this study we could demonstrate that stretch up to 21% caused dose-dependent changes in biological markers such as the calcineurin activity, modulatory calcineurin-interacting protein-1, voltage-gated potassium channel isoform 4.2, and voltage-gated K+ channel-interacting proteins-2 gene expression and transient outward potassium current densities but not the protein-to-DNA ratio and atrial natriuretic peptide mRNA. With both markers mentioned last, dose-dependent stretch alterations could only be achieved with stretch up to 13%. The simple and low-cost device presented here might be applied to a wide range of experimental settings in different fields of research.

Download Full-text

Improved LC-MS chromatographic alignment increases the accuracy of label-free quantitative proteomics: Comparison of spectral counting versus ion intensity-based proteomic quantification strategies

10.1101/111476 ◽

2017 ◽

Cited By ~ 1

Author(s):

Daniel H.J. Ng ◽

Jonathan D. Humphries ◽

Julian N. Selley ◽

Stacey Warwood ◽

David Knight ◽

...

Keyword(s):

Cell Biology ◽

Low Cost ◽

Quantitative Description ◽

Protein Quantification ◽

Global Changes ◽

Label Free ◽

Spectral Counting ◽

Differential Abundance ◽

Mass Spectrometers ◽

Wide Range

AbstractThe ability to provide an unbiased qualitative and quantitative description of the global changes to proteins in a cell or an organism would permit the systems-wide study of complex biological systems. Label-free quantitative shotgun proteomic strategies (including LC-MS ion intensity quantification and spectral counting) are attractive because of their relatively low cost, ease of implementation, and the lack of multiplexing restrictions when comparing multiple samples. Owing to improvements in the resolution and sensitivity of mass spectrometers, and the availability of analytical software packages, protein quantification by LC-MS ion intensity has increased in popularity. Here, we have addressed the importance of chromatographic alignment on protein quantification, and then assessed how spectral counting compares to ion intensity-based proteomic quantification. Using a spiked-in protein strategy, we analysed two situations that commonly arise in the application of proteomics to cell biology: (i) samples with a small number of proteins of differential abundance in a larger non-changing background, and (ii) samples with a larger number of proteins of differential abundance. To perform these assessments on biologically relevant samples, we used isolated integrin adhesion complexes (IACs). Technical replicate analysis of isolated IACs resulted in a range of alignment scores using the Progenesis QI software package and demonstrated that higher LC-MS chromatographic alignment scores increased the precision of protein quantification. Furthermore, implementation of a simple sample batch-running strategy enabled good chromatographic alignment for hundreds of samples over multiple batches. Finally, we applied the sample batch-running strategy and compared quantification by LC-MS ion intensity to spectral counting and found that quantification by LC-MS ion intensity was more accurate and precise. In summary, these results demonstrate that chromatographic alignment is important for precise and accurate protein quantification based on LC-MS ion intensity and accordingly we present a simple sample re-ordering strategy to facilitate improved alignment. These findings are not only relevant to label-free quantification using Progenesis QI but may be useful to the wide range of MS-based quantification strategies that rely on chromatographic alignment.

Download Full-text

Thiopental and Methohexital Depress Ca2+Entry into and Glutamate Release from Cultured Neurons

Anesthesiology ◽

10.1097/00000542-199806000-00029 ◽

1998 ◽

Vol 88 (6) ◽

pp. 1643-1653 ◽

Cited By ~ 17

Author(s):

Ning Miao ◽

Kaoru Nagao ◽

Carl Lynch

Keyword(s):

Calcium Channel ◽

Glutamate Release ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Neonatal Rat ◽

Reduced Form ◽

Dependent Manner ◽

Protective Effects ◽

Voltage Gated ◽

Voltage Gated Calcium Channel ◽

Dose Dependent

Background Although barbiturates activate alpha-aminobutyric acid type A receptors as part of their hypnotic effect, these drugs also inhibit voltage-gated calcium channels. The authors determined if barbiturates could decrease neuronal intracellular Ca2+ transients and the resulting glutamate release. Methods Neonatal rat cerebellar granule neurons were isolated and cultured on coverslips and studied at 37 degrees C. Spectrofluorometric assays were used during identical conditions to monitor intracellular Ca2+ with the Ca2+ -sensitive fluorophore fura-2 and glutamate release by a glutamate dehydrogenase-coupled assay, which produced the reduced form of nicotinamide-adenine dinucleotide phosphate in proportion to the amount of glutamate released. Neurons were depolarized by a rapid increase in external [K+] from 5 to 55 mM. Control responses were compared with those in the presence of 10, 30, and 100 microM thiopental; 3, 10, and 30 microM methohexital; decreased external [Ca2+]; or voltage-gated calcium channel blockers. Results Thiopental and methohexital depressed the intracellular Ca2+ transient peak and plateau in a dose-dependent manner, as did decreased Ca2+. The intermediate dose of either drug caused approximately 50% decrease in peak intracellular Ca2+ and 60% decrease in glutamate release. In the presence of specific L- and/or N-type voltage-gated calcium channel blockade by nicardipine or omega-conotoxin-GVIA, respectively, 30 microM thiopental further decreased the intracellular Ca2+ transient. Thiopental caused a dose-dependent decrease in glutamate release, which was proportional to the decreased peak intracellular Ca2+. Conclusions Thiopental and methohexital depress the depolarization-induced increase in intracellular Ca2+ and the accompanying glutamate release, actions which can contribute to the anesthetic and neuronal protective effects of these drugs.

Download Full-text

Information and information resources in COVID-19: Awareness, control, and prevention

Journal of Librarianship and Information Science ◽

10.1177/09610006211016519 ◽

2021 ◽

pp. 096100062110165

Author(s):

Mohammadhiwa Abdekhoda ◽

Fatemeh Ranjbaran ◽

Asghar Sattari

Keyword(s):

Low Cost ◽

Information Resources ◽

Age And Gender ◽

Use Of Resources ◽

Strategic Approach ◽

Wide Range ◽

Data Collection Instrument ◽

Control And Prevention ◽

And Gender ◽

And Control

This study was conducted with the aim of evaluating the role of information and information resources in the awareness, control, and prevention of COVID-19. This study was a descriptive-analytical survey in which 450 participants were selected for the study. The data collection instrument was a researcher-made questionnaire. Descriptive and inferential statistics were used to analyze the data through SPSS. The findings show that a wide range of mass media has become well known as information resources for COVID-19. Other findings indicate a significant statistical difference in the rate of using information resources during COVID-19 based on age and gender; however, this difference is not significant regarding the reliability of information resources with regard to age and gender. Health information has an undisputable role in the prevention and control of pandemic diseases such as COVID-19. Providing accurate, reliable, and evidence-based information in a timely manner for the use of resources and information channels related to COVID-19 can be a fast and low-cost strategic approach in confronting this disease.

Download Full-text

Advanced mycelium materials as potential self-growing biomedical scaffolds

Scientific Reports ◽

10.1038/s41598-021-91572-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maria Elena Antinori ◽

Marco Contardi ◽

Giulia Suarato ◽

Andrea Armirotti ◽

Rosalia Bertorelli ◽

...

Keyword(s):

Tissue Engineering ◽

Low Cost ◽

Direct Interaction ◽

Dermal Fibroblasts ◽

Engineering Systems ◽

Edible Fungi ◽

Avant Garde ◽

Fibrous Network ◽

Body Tissues ◽

Wide Range

AbstractMycelia, the vegetative part of fungi, are emerging as the avant-garde generation of natural, sustainable, and biodegradable materials for a wide range of applications. They are constituted of a self-growing and interconnected fibrous network of elongated cells, and their chemical and physical properties can be adjusted depending on the conditions of growth and the substrate they are fed upon. So far, only extracts and derivatives from mycelia have been evaluated and tested for biomedical applications. In this study, the entire fibrous structures of mycelia of the edible fungi Pleurotus ostreatus and Ganoderma lucidum are presented as self-growing bio-composites that mimic the extracellular matrix of human body tissues, ideal as tissue engineering bio-scaffolds. To this purpose, the two mycelial strains are inactivated by autoclaving after growth, and their morphology, cell wall chemical composition, and hydrodynamical and mechanical features are studied. Finally, their biocompatibility and direct interaction with primary human dermal fibroblasts are investigated. The findings demonstrate the potentiality of mycelia as all-natural and low-cost bio-scaffolds, alternative to the tissue engineering systems currently in place.

Download Full-text

Rheology and Water Absorption Properties of Alginate–Soy Protein Composites

Polymers ◽

10.3390/polym13111807 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1807

Author(s):

Estefanía Álvarez-Castillo ◽

José Manuel Aguilar ◽

Carlos Bengoechea ◽

María Luisa López-Castejón ◽

Antonio Guerrero

Keyword(s):

Soy Protein ◽

Water Solubility ◽

Divalent Cations ◽

Low Cost ◽

Soy Protein Isolate ◽

Protein Isolate ◽

Guluronic Acid ◽

Wide Range ◽

Anionic Polysaccharides ◽

Porous Matrices

Composite materials based on proteins and carbohydrates normally offer improved water solubility, biodegradability, and biocompatibility, which make them attractive for a wide range of applications. Soy protein isolate (SPI) has shown superabsorbent properties that are useful in fields such as agriculture. Alginate salts (ALG) are linear anionic polysaccharides obtained at a low cost from brown algae, displaying a good enough biocompatibility to be considered for medical applications. As alginates are quite hydrophilic, the exchange of ions from guluronic acid present in its molecular structure with divalent cations, particularly Ca2+, may induce its gelation, which would inhibit its solubilization in water. Both biopolymers SPI and ALG were used to produce composites through injection moulding using glycerol (Gly) as a plasticizer. Different biopolymer/plasticizer ratios were employed, and the SPI/ALG ratio within the biopolymer fraction was also varied. Furthermore, composites were immersed in different CaCl2 solutions to inhibit the amount of soluble matter loss and to enhance the mechanical properties of the resulting porous matrices. The main goal of the present work was the development and characterization of green porous matrices with inhibited solubility thanks to the gelation of alginate.

Download Full-text

Optically transparent and very thin structure against electromagnetic pulse (EMP) using metal mesh and saltwater for shielding windows

Scientific Reports ◽

10.1038/s41598-021-80969-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Duy Tung Phan ◽

Chang Won Jung

Keyword(s):

Electromagnetic Pulse ◽

Low Cost ◽

High Energy ◽

Metal Plate ◽

Optical Transparency ◽

Shielding Effectiveness ◽

Concrete Wall ◽

Metal Mesh ◽

Wide Range ◽

Optically Transparent

AbstractAn electromagnetic pulse (EMP) with high energy can damage electronic equipment instantly within a wide range of thousands of kilometers. Generally, a metal plate placed inside a thick concrete wall is used against an EMP, but it is not suitable for an EMP shielding window, which requires not only strong shielding effectiveness (SE) but also optical transparency (OT). In this paper, we propose a very thin and optically transparent structure with excellent SE for EMP shielding window application. The proposed structure consists of a saltwater layer held between two glass substrates and two metal mesh layers on the outside of the glass, with a total thickness of less than 1.5 cm. The SE and OT of the structure are above 80 dB and 45%, respectively, which not only meet the requirement of EMP shielding for military purposes but also retain the procedure of good observation. Moreover, the OT of the structure can be significantly improved using only one metal mesh film (MMF) layer, while the SE is still maintained high to satisfy the required SE for home applicants. With the major advantages of low cost, optical transparency, strong SE, and flexible performance, the proposed structure can be considered a good solution for transparent EMP shielding windows.

Download Full-text

Photocatalytic three-component asymmetric sulfonylation via direct C(sp3)-H functionalization

Nature Communications ◽

10.1038/s41467-021-22690-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Shi Cao ◽

Wei Hong ◽

Ziqi Ye ◽

Lei Gong

Keyword(s):

Asymmetric Catalysis ◽

Organic Synthesis ◽

Photochemical Reaction ◽

Low Cost ◽

Bioactive Molecules ◽

Atom Economy ◽

Mild Conditions ◽

Wide Range ◽

Unsaturated Carbonyl Compound ◽

Direct Functionalization

AbstractThe direct and selective C(sp3)-H functionalization of cycloalkanes and alkanes is a highly useful process in organic synthesis owing to the low-cost starting materials, the high step and atom economy. Its application to asymmetric catalysis, however, has been scarcely explored. Herein, we disclose our effort toward this goal by incorporation of dual asymmetric photocatalysis by a chiral nickel catalyst and a commercially available organophotocatalyst with a radical relay strategy through sulfur dioxide insertion. Such design leads to the development of three-component asymmetric sulfonylation involving direct functionalization of cycloalkanes, alkanes, toluene derivatives or ethers. The photochemical reaction of a C(sp3)-H precursor, a SO2 surrogate and a common α,β-unsaturated carbonyl compound proceeds smoothly under mild conditions, delivering a wide range of biologically interesting α-C chiral sulfones with high regio- and enantioselectivity (>50 examples, up to >50:1 rr and 95% ee). This method is applicable to late-stage functionalization of bioactive molecules, and provides an appealing access to enantioenriched compounds starting from the abundant hydrocarbon compounds.

Download Full-text

Glycans in scaffold design in tissue reconstruction

Journal of Bioactive and Compatible Polymers ◽

10.1177/0883911521997847 ◽

2021 ◽

pp. 088391152199784

Author(s):

Nipun Jain ◽

Shashi Singh

Keyword(s):

Cell Attachment ◽

Low Cost ◽

Growth Conditions ◽

Downstream Signaling ◽

Cell Carrier ◽

Wide Range ◽

Proliferation And Differentiation ◽

Different Types ◽

Tissue Reconstruction ◽

A Cell

Development of an artificial tissue by tissue engineering is witnessed to be one of the long lasting clarified solutions for the damaged tissue function restoration. To accomplish this, a scaffold is designed as a cell carrier in which the extracellular matrix (ECM) performs a prominent task of controlling the inoculated cell’s destiny. ECM composition, topography and mechanical properties lead to different types of interactions between cells and ECM components that trigger an assortment of cellular reactions via diverse sensing mechanisms and downstream signaling pathways. The polysaccharides in the form of proteoglycans and glycoproteins yield better outcomes when included in the designed matrices. Glycosaminoglycan (GAG) chains present on proteoglycans show a wide range of operations such as sequestering of critical effector morphogens which encourage proficient nutrient contribution toward the growing stem cells for their development and endurance. In this review we discuss how the glycosylation aspects are of considerable importance in everyday housekeeping functions of a cell especially when placed in a controlled environment under ideal growth conditions. Hydrogels made from these GAG chains have been used extensively as a resorbable material that mimics the natural ECM functions for an efficient control over cell attachment, permeability, viability, proliferation, and differentiation processes. Also the incorporation of non-mammalian polysaccharides can elicit specific receptor responses which authorize the creation of numerous vigorous frameworks while prolonging the low cost and immunogenicity of the substance.

Download Full-text

Burkholderia thailandensis E264 as a promising safe rhamnolipids’ producer towards a sustainable valorization of grape marcs and olive mill pomace

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11292-0 ◽

2021 ◽

Author(s):

Alif Chebbi ◽

Massimiliano Tazzari ◽

Cristiana Rizzi ◽

Franco Hernan Gomez Tovar ◽

Sara Villa ◽

...

Keyword(s):

Energy Source ◽

Olive Oil ◽

Low Cost ◽

Carbon Sources ◽

Burkholderia Thailandensis ◽

Rhamnolipid Production ◽

Key Points ◽

Wide Range ◽

Long Chain ◽

Olive Mill

Abstract Within the circular economy framework, our study aims to assess the rhamnolipid production from winery and olive oil residues as low-cost carbon sources by nonpathogenic strains. After evaluating various agricultural residues from those two sectors, Burkholderia thailandensis E264 was found to use the raw soluble fraction of nonfermented (white) grape marcs (NF), as the sole carbon and energy source, and simultaneously, reducing the surface tension to around 35 mN/m. Interestingly, this strain showed a rhamnolipid production up to 1070 mg/L (13.37 mg/g of NF), with a higher purity, on those grape marcs, predominately Rha-Rha C14-C14, in MSM medium. On olive oil residues, the rhamnolipid yield of using olive mill pomace (OMP) at 2% (w/v) was around 300 mg/L (15 mg/g of OMP) with a similar CMC of 500 mg/L. To the best of our knowledge, our study indicated for the first time that a nonpathogenic bacterium is able to produce long-chain rhamnolipids in MSM medium supplemented with winery residues, as sole carbon and energy source. Key points • Winery and olive oil residues are used for producing long-chain rhamnolipids (RLs). • Both higher RL yields and purity were obtained on nonfermented grape marcs as substrates. • Long-chain RLs revealed stabilities over a wide range of pH, temperatures, and salinities

Download Full-text

Applicability of Cork as Novel Modifiers to Develop Electrochemical Sensor for Caffeine Determination

Materials ◽

10.3390/ma14010037 ◽

2020 ◽

Vol 14 (1) ◽

pp. 37

Author(s):

Mayra K. S. Monteiro ◽

Djalma R. Da Silva ◽

Marco A. Quiroz ◽

Vítor J. P. Vilar ◽

Carlos A. Martínez-Huitle ◽

...

Keyword(s):

Electrochemical Sensor ◽

Linear Response ◽

High Performance ◽

Low Cost ◽

Pharmaceutical Formulations ◽

Caffeine Concentration ◽

Real Samples ◽

Wide Range ◽

Potential Use

This study aims to investigate the applicability of a hybrid electrochemical sensor composed of cork and graphite (Gr) for detecting caffeine in aqueous solutions. Raw cork (RAC) and regranulated cork (RGC, obtained by thermal treatment of RAC with steam at 380 °C) were tested as modifiers. The results clearly showed that the cork-graphite sensors, GrRAC and GrRGC, exhibited a linear response over a wide range of caffeine concentration (5–1000 µM), with R2 of 0.99 and 0.98, respectively. The limits of detection (LOD), estimated at 2.9 and 6.1 µM for GrRAC and GrRGC, suggest greater sensitivity and reproducibility than the unmodified conventional graphite sensor. The low-cost cork-graphite sensors were successfully applied in the determination of caffeine in soft drinks and pharmaceutical formulations, presenting well-defined current signals when analyzing real samples. When comparing electrochemical determinations and high performance liquid chromatography measurements, no significant differences were observed (mean accuracy 3.0%), highlighting the potential use of these sensors to determine caffeine in different samples.

Download Full-text