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Cell migration is a highly integrated process and basic to many biological functions ranging from development to immune response and wound healing, to metastasis in cancer. For cells to migrate, they must generate and transduce traction forces to their environment, however, no technology to date has provided a high throughput solution for measuring these traction forces. Here we present a new assay for measuring cellular contractile forces employing robust multiwall culture plates: Using a 96-well plate format, we fabricate soft (∼1-10 kPa) elastic silicone rubbers with embedded fiduciary particles; by measuring the cell-induced deformation of these particles we calculate the cellular traction stresses and work using Fourier transform cytometry. We utilize this system to quantify the traction mechanics underlying cellular migration in several diseased settings including cancer metastasis, induced epithelial to mesenchymal transition (EMT), and aging; in all instances, we find significant changes in the contractile stresses and work, suggesting that contractile force screening may become a valuable biophysical diagnostic addition. This 96-well format and the use of a non-degrading soft silicone rubber create a simple and stable assay, and we anticipate that this technology will be of broad utility in diverse quantitative biological and health sciences.

Recent evidence indicates that branched actin might control cell progression through G1 in addition to lamellipodium protrusion.

Traditional synthetic substrates and matrices for cell culture have proven to be of only limited utility in efforts to understand and control cell behavior, in large part because they fail to capture the multifarious biochemical, mechanical, geometric and dynamic characteristics of in vivo environments. However, recent advances in materials chemistry and engineering have begun to provide researchers with a toolbox to mimic the complex characteristics of natural extracellular matrices (ECMs), providing new pathways to explore cell–matrix interactions and direct cell fate under physiologically realistic conditions. In this review, we describe recent developments in stimuli-responsive materials as dynamic substrates and matrices for cell culture, and highlight their use in furthering our understanding of how cells respond to temporal variations in their environment.

During embryonic development, cells must divide to produce appropriate numbers, but later must exit the cell cycle to allow differentiation. How these processes of proliferation and differentiation are co-ordinated during embryonic development has been poorly understood until recently. However, a number of studies have now given an insight into how the cell cycle machinery, including cyclins, CDKs (cyclin-dependent kinases), CDK inhibitors and other cell cycle regulators directly influence mechanisms that control cell fate and differentiation. Conversely, examples are emerging of transcriptional regulators that are better known for their role in driving the differentiated phenotype, which also play complementary roles in controlling cell cycle progression. The present review will summarise our current understanding of the mechanisms co-ordinating the cell cycle and differentiation in the developing nervous system, where these links have been, perhaps, most extensively studied.

In situ vascular tissue engineering has been proposed as a promising approach to fulfill the need for small-diameter blood vessel substitutes. The approach comprises the use of a cell-free instructive scaffold to guide and control cell recruitment, differentiation, and tissue formation at the locus of implantation. Here we review the design parameters for such scaffolds, with special emphasis on differentiation of recruited ECFCs into the different lineages that constitute the vessel wall. Next to defining the target properties of the vessel, we concentrate on the target cell source, the ECFCs, and on the environmental control of the fate of these cells within the scaffold. The prospects of the approach are discussed in the light of current technical and biological hurdles.

Cell signaling is mostly studied in in vitro 2D-cell culture models that lack the complex in vivo environment provided by neighboring cells, soluble secreted factors and non-cellular matrix components. Given that many environmental factors control cell signaling, it comes as no surprise that in vitro observations often poorly correlate with in vivo observations. Recent developments in intravital imaging techniques have made it possible to visualize and study cell signaling in individual cells within living animals. Here, we review intravital imaging techniques based on fluorescence microscopy and give examples of how these techniques are being used to study cell signaling.

The kinases have been intensely studied because of their involvement in regulating essential cellular activation of signaling cascades in response to extracellular and intracellular stimuli to control cell growth, proliferation, and survival. Recent cancer genomic sequencing studies have revealed that many more kinases contribute to tumor genesis and are potential targets for inhibitor drug development intervention. Herein we review recent results that have helped to unravel the indolin-2-ones underlying the confiicting roles of the kinase inhibition regulation. This review focuses on the potential of kinases as a chemotherapeutic target in cancer treatment and highlights important recent advances in the development of indolin-2-ones as kinase inhibitors.

In response to environmental stresses, cells need to activate an adaptive program to maximize cell progression and survival. Stress-activated protein kinases (SAPK) are key signal transduction kinases required to respond to stress. Prototypical members of SAPKs are the yeast Hog1 and mammalian p38. Upon stress, those enzymes play a critical role in mounting the adaptive responses to stress such as the regulation of metabolism and the control of gene expression. In addition, a major function of SAPKs in response to stress is to modulate cell cycle progression. In this review, we focus on the role of Hog1 and p38 in the control of cell cycle progression in response to environmental stresses.

PERK is a major sensor of the unfolded protein response controlling cell fate under endoplasmic reticulum (ER) stress. A new study reveals an additional step for optimal PERK signaling, involving the binding of CNPY2 to PERK's luminal domain. The PERK–CNPY2 axis was shown to enhance cell death under ER stress in vivo influence liver disease.

Cancer cell lines are the basic material for various lines of cancer research. Diverse cancer cell lines derived from tissues of various head and neck regions are needed for biological research on head and neck cancer. However, cell lines derived from cancer of the head and neck are not common. Recently, we established and characterized a novel human squamous carcinoma cell line, CNUH-HNSCC-1. From six cases of head and neck cancer, we established one specimen that was maintained for over 50 passages. We characterized the cell line as follows: growth patterns and curve, morphology by use of phase-contrast microscopy, and tumorigenicity by implanting the cell line into nude mice and making morphological comparisons. CNUH-HNSCC-1 cells grew well in vitro even after passage 50. However, the cells failed to form tumors in nude mice. CNUH-HNSCC-1 cells could be used as a control cell line for studying the biology of head and neck cancer.

SummaryHow complex networks of activators and repressors lead to exquisitely specific cell-type determination during development is poorly understood. In the Drosophila eye, expression patterns of Rhodopsins define at least eight functionally distinct though related subtypes of photoreceptors. Here, we describe a role for the transcription factor gene defective proventriculus (dve) as a critical node in the network regulating Rhodopsin expression. dve is a shared component of two opposing, interlocked feedforward loops (FFLs). Orthodenticle and Dve interact in an incoherent FFL to repress Rhodopsin expression throughout the eye. In R7 and R8 photoreceptors, a coherent FFL relieves repression by Dve while activating Rhodopsin expression. Therefore, this network uses repression to restrict and combinatorial activation to induce cell-type-specific expression. Furthermore, Dve levels are finely tuned to yield cell-type- and region-specific repression or activation outcomes. This interlocked FFL motif may be a general mechanism to control terminal cell-fate specification.

Sphingosine kinase (SPHK) has a central role to control cell death and cell proliferation, which is suggested as a sphingolipid rheostat by regulating the levels between ceramide and sphingosine 1-phosphate (S1P). Therefore, physiological regulators of SPHK will be a good candidate to develop a new targeted drug. For this purpose, a series of synthetic pseudoceramides were tested by SPHK assay either cell-based or cell-free system. K10PC-5 strongly inhibited SPHK, while K6PC-5 activated SPHK in cell-free system. Specifically, K6PC-5 activated SPHK under the co-treatment with 50 uM dimethylsphingosine (DMS), a SPHK inhibitor. Collectively, we developed a simple SPHK assay system to find SPHK regulatory pseudoceramide compounds, K10PC-5 and K6PC-5 which may be useful to cancer treatment or immune regulation like FTY720, a synthetic sphingolipid mimetic compound.

This paper presents the working principle of rapid prototyping technology based on fused deposition modeling (FDM) and summaries its technology features. The basic constitution of FDM system, such as mechanical device and control cell, are discussed, respectively. Selecting a deep groove ball bearing as experimental object and manufactured in the MEM320A rapid prototyping machine to demonstrate the FDM fabrication process. Investigate into the application of FDM on production design, function demonstration and biomedical engineering. Finally, the future development of FDM is prospected.

Nanostructures play important roles in vivo, where nanoscaled features of extracellular matrix (ECM) components influence cell behavior and resultant tissue formation. This review summarizes some of the recent developments in fostering new concepts and approaches to nanofabrication, such as top-down and bottom-up and combinations of the two. As in vitro investigations demonstrate that man-made nanotopography can be used to control cell reactions to a material surface, its potential application in implant design and tissue engineering becomes increasingly evident. Therefore, we present recent progress in directing cell fate in the field of cell mechanics, which has grown rapidly over the last few years, and in various tissue-engineering applications. The main focus is on the initial responses of cells to nanostructured surfaces and subsequent influences on cellular functions. Specific examples are also given to illustrate the potential nanostructures may have for biomedical applications and regenerative medicine.

Rationale: Tetraspanins are cell membrane–spanning proteins that transduce extracellular signals and control cell adhesion via interactions with multiple molecules, including the protein immunoglob...

During neural development, massive cell death occurs in both vertebrates and invertebrates. Caspase is a central player in apoptosis that is evolutionally conserved. Genetic manipulation of the caspase activity in Drosophila and mice has revealed that caspases control cell fate through apoptotic and non-apoptotic mechanisms, to ensure appropriate cell differentiation and maturation in the developing nervous system.

In this paper, a novel design for single-layer half width microstrip leakywave antenna (HW-MLWA) is demonstrated. This model can be digitally control its radiation pattern at operation frequency and uses only two values of the bias voltage, with better impedance matching and insignificant gain variation. The scanning and controlling the radiation pattern of leaky-wave antennas (LWA) in steps at an operation frequency, by using switches PIN diodes, is investigated and a novel HW-MLWA is introduced. A control cell reconfigurable, that can be switched between two states, is the basic element of the antenna. The periodic LWA is molded by identical control cells where as a control radiation pattern is developed by combining numerous reconfigurable control cells. A gap capacitor is independently connected or disconnected in every unit cell by using a PIN diode switch to achieve fixedfrequency control radiation pattern scanning. The profile reactance at the free edge of (HW-MLWA) and thus the main lobe direction is altered by changing the states of the control cell. The antenna presented in this paper, can scan main beam between 18o to 44o at fixed frequency of 4.2 GHz with measured peak gain of 12.29 dBi.

Cell differentiation has a crucial role in both artificial and natural developments. This paper presents results from simulations in which a genetic algorithm (GA) was used to evolve artificial regulatory networks (ARNs) to produce predefined 3D cellular structures through the selective activation and inhibition of genes. The ARNs used in this work are extensions of a model previously used to create 2D geometrical patterns. The GA worked by evolving the gene regulatory networks that were used to control cell reproduction, which took place in a testbed based on cellular automata (CA). After the final chromosomes were produced, a single cell in the middle of the CA lattice was allowed to replicate controlled by the ARN found by the GA, until the desired cellular structures were formed. Two simple cubic layered structures were first developed to test multiple gene synchronization. The model was then applied to the problem of generating a 3D French flag pattern using morphogenetic gradients to provide cells with positional information that constrained cellular replication.

The ability to recognize and react to specific environmental cues allows bacteria to localize to environments favorable to their survival and growth. Synthetic biologists have begun to exploit the chemosensory pathways that control cell motility to reprogram how bacteria move in response to novel signals. Reprogramming is often accomplished by designing novel protein or RNA parts that respond to specific small molecules not normally recognized by the natural chemosensory pathways. Additionally, cell motility and localization can be coupled to bacterial quorum sensing, potentially allowing consortia of cells to perform complex tasks.

Synthetic Biology Synthetic genetic and biological regulatory circuits can enable logic functions to form the basis of biological computing; synthetic biology can also be used to control cell behaviors (see the Perspective by Glass and Alon). Andrews et al. used mathematical models and computer algorithms to combine standardized components and build programmable genetic sequential logic circuits. Such circuits can perform regulatory functions much like the biological checkpoint circuits of living cells. Circuits composed of interacting proteins could be used to bypass gene regulation, interfacing directly with cellular pathways without genome modification. Gao et al. engineered proteases that regulate one another, respond to diverse inputs that include oncogene activation, process signals, and conditionally activate responses such as those leading to cell death. This platform should facilitate development of “smart” therapeutic circuits for future biomedical applications. Science , this issue p. [eaap8987][1], p. [1252][2]; see also p. [1199][3] [1]: /lookup/doi/10.1126/science.aap8987 [2]: /lookup/doi/10.1126/science.aat5062 [3]: /lookup/doi/10.1126/science.aav2497

Over the last dozen years, studies at the cell and tissue level have demonstrated that the function and fate of all cells, stem cells in particular, are affected by the collective physical properties of their microenvironments. Meanwhile, biophysical studies at the single molecule level have taught us a great deal about how mechanical forces affect the structure and function of proteins involved in the assembly of cells into tissues. Together, these molecular, cellular, and tissue studies provide insight into the process and importance of mechanotransduction, which is the process by which mechanical forces are transduced into biological signals. This insight should motivate biomimetic approaches to better control cell fate and tissue function.

Single-celled organisms monitor cell geometry and use this information to control cell division. Such geometry-sensing mechanisms control both the decision to enter into cell division and the physical orientation of the chromosome segregation machinery, suggesting that signals controlling cell division may be linked to the mechanisms that ensure proper chromosome segregation.

Cancer A full understanding of cancer evolution needs a systematic approach. Screening for genes that drive unrestrained proliferation of human cells could answer questions about the relative roles of mutations, gene dose, and tissue specificity in cancer development. To find those for which dosage

Genomic and clinical evidence suggest a major role of microRNAs (miRNAs) in the regulatory mechanisms of gene expression, with a clear impact on development and physiology; miRNAs are a class of endogenous 22-25 nt single-stranded RNA molecules, that negatively regulate gene expression post-transcriptionally, by imperfect base pairing with the 3’ UTR of the corresponding mRNA target. Because of this imperfection, each miRNA can bind multiple targets, and multiple miRNAs can bind the same mRNA target; although digital, the miRNAs control mechanism is characterized by an imprecise action, naturally understandable in the theoretical framework of fuzzy logic. A major practical application of fuzzy logic is represented by the design and the realization of efficient and robust control systems, even when the processes to be controlled show chaotic, deterministic as well unpredictable, behaviours. The vagueness of miRNA action, when considered together with the controlled and chaotic gene expression, is a hint of a cellular fuzzy control system. As a demonstration of the possibility and the effectiveness of miRNA based fuzzy mechanism, a fuzzy cognitive map -a mathematical formalism combining neural network and fuzzy logic- has been developed to study the apoptosis/proliferation control performed by the miRNA-17-92 cluster/E2F1/cMYC circuitry. When experimentally demonstrated, the concept of fuzzy control could modify the way we analyse and model gene expression, with a possible impact on the way we imagine and design therapeutic intervention based on miRNA silencing.

The field of companion diagnostics is an expanding area in which industry can make significant contributions to the quality and reliability of prognostic and predictive assays. HER2 testing by immunohistochemistry and in situ hybridization, by virtue of its semi-quantitative nature demands the highest level of reagent quality and consistency. We describe a unique manufacturing practice that is used to guarantee the quality of control cell line slides provided for controlling the staining procedure and ensuring the validity of the reagent performance. An IHC control that could reflect variations in fixation, processing, section thickness, section storage and staining protocols would provide a useful tool for improved standardization. One way to ensure such accuracy and reproducibility of HER2 testing is by using robust internal controls. We intend to present for the first time, details of a unique manufacturing process, that of interferometry, the technique of using the pattern of interference created by the superposition of 2 or more waves to diagnose the properties of the aforementioned waves, that is, "section thickness," to guarantee the quality and consistency of internal cell line controls that can be used in a HER2 testing assay.

Cell cytosol and the different subcellular organelles house the most important biochemical processes that control cell functions. Effective delivery of bioactive agents within cells is expected to have an enormous impact on both gene therapy and the future development of new therapeutic and/or diagnostic strategies based on single-cell-bioactive-agent interactions. Herein a biomimetic nanovector is reported that is able to enter cells, escape from the complex endocytic pathway, and efficiently deliver actives within clinically relevant cells without perturbing their metabolic activity. This nanovector is based on the pH-controlled self-assembly of amphiphilic copolymers into nanometer-sized vesicles (or polymersomes). The cellular-uptake kinetics can be regulated by controlling the surface chemistry, the polymersome size, and the polymersome surface topology. The latter is controlled by the extent of polymer-polymer phase separation within the external envelope of the polymersome.

A significant challenge in implantology is the design of biomaterials that actively promote functional regeneration of the host tissue while avoiding undesirable tissue responses. This requires selective control of interactions at the tissue/implant interface, the site of a series of complex events that depend on synergistic parameters including surface chemistry, elasticity, topography, and energy. To date, efforts have focused largely on defining how microtexture influences the molecular and cellular events of tissue repair. However, it is now widely recognized that biological substrates on which cells thrive consist of nanostructured molecular networks, and the sensing apparatus of cells operates on the nanometer scale. Reports have emerged showing that nanometer-scale surface features can influence cellular attachment, differentiation, and alignment. The present study takes an important further step by showing how simple chemical treatment can generate multifunctional nanostructured surfaces that control cell growth selectively. These surfaces promote the growth of certain cells while inhibiting that of others, without the addition of any exogenous biological or pharmacological agents. Cellular response to the surface features in the micrometerrange such as grooves, ridges, and wells has been well established. In the past few years, interest has shifted to evaluating the potential of nanostructured biomaterials for affecting cellular activity. Work in this area has been facilitated by recent advances in technologies used to modify

The last decade has witnessed an exponential increase in interest in one of the great mysteries of nerve cell biology: Specifically, how do neurons know where to place the ion channels that control their excitability? Many of the most important insights have been gleaned from studies on the voltage-gated potassium channels (Kvs) which underlie the shape, duration and frequency of action potentials. In this review, we gather recent evidence on the expression, trafficking and maintenance mechanisms which control the surface density of Kvs in different subcellular compartments of neurons and how these may be regulated to control cell excitability.

The aim of this work is to examine how adhered individual cells could detach from the patterned, discontinuous thermoresponsive coating substrate and how different patterns in the form of thermoresponsive squares and gaps would affect cell detachment. Microgels prepared from copolymerization of N-isopropylacrylamide and styrene (pNIPAAmSt) were spin-coated on polyethylenimine (PEI) precoated glass coverslips to form a uniform microgel monolayer; then a surface-moisturized PMDS stamp was used to contact the microgel monolayer at room temperature. The thin layer of water on the PDMS stamp surface worked as an ink to penetrate the microgels so that any microgels in direct contact with the wet stamp surface became swollen and could be peeled away, while uncontacted microgels formed patterns. Using this method, various patterns with different thermo-island diameters and gaps could be fabricated. NIH3T3 fibroblast cells were then cultured on these patterns to study their detachment behavior. It was found that cells could detach not only from these discontinuous thermoresponsive coatings, but also from the patterned surfaces with the thermoresponsive area being as low as 20% of the cell spread area.

A critical step in successful engraftment of engineered tissue substitutes is the development of functional vascularized networks. Vascularization of complex tissue constructs requires a combination of expertise in biological science, engineering, and biomaterials synthesis. Microengineering technology has found extensive applications in creating spatially patterned features with well-defined chemical and physical cues to control cell and tissue functions. In this chapter, we will broadly overview the recent progress in the integration of microengineering technology (e.g., spatial patterning techniques) and stem cells to develop microvascular networks. We will primarily describe the characteristics and architecture of native blood vessels followed by a brief presentation on specific cell types, biological signals, and biomaterials, which have been applied to create biomimetic vascular networks. We will then highlight the studies, which have utilized photolithography, soft lithography, and advanced biomanufacturing techniques to spatially pattern stem cells to generate blood vessel-like networks. This chapter will be concluded with a brief summary on the effects of mechanical stimulations on vascular assembly.

Due to their many attractive features, alginate hydrogels are amongst the most commonly used cell-entrapment matrices. They structurally recapitulate key features of native extracellular matrices and can be further bio-functionalized with cell-instructive moieties to specifically control cell behavior. The biomechanical properties of alginate hydrogels can be tuned to match those of different types of tissues, increasing their versatility. This review provides an overview on the general properties of alginate hydrogels and their application as injectable cell carriers for tissue regeneration, namely for therapeutic vascularization.

Biodegradable polyurethane scaffolds have been used to control cell fate and tissue regeneration. Scaffold properties including chemical, mechanical, and structural affect cell adhesion, spreading, proliferation, and differentiation. These properties are determined by the chemistry of biodegradable polyurethanes, scaffold fabrication techniques, and surface modification approaches. In this chapter, we review the effect of chemical, mechanical, and structural properties of nanofibrous scaffolds, microporous scaffolds, multilayered scaffolds, and scaffolds with nanostructured surfaces, on cell fate and tissue regeneration. Current challenges in determining the relationship of scaffold properties and cell fate are discussed and future perspectives are addressed.

Editorials: Cell Cycle Features., Cells must grow to reach a critical size before cell division. In 1977 Fantes and Nurse established that this critical size depends on the nutritional environment.

Membrane electropermeabilization is observed when electric pulses over a critical strength are delivered on a cell suspension. This is associated with a time dependent change in the suspension conductance. The magnitude and the kinetics of the conductivity changes can be used to get access to the molecular event supporting the membrane electropermeabilization. In Bioprocesses, where extraction results from electropermeabilization, the control of the conductivity change of the cell suspension allows the definition of optimized safe conditions.

Development of microfluidic culture technology combined with tissue engineering catalyzes the progress in study of cell biology. These tools will promote the understanding of physiological and pathological changes. Cancer cells and stem cells are sensitive to their surroundings, thus could be better explored by controllable microfluidic devices. In this review, we describe the ways to control cell microenvironment and explain how the influencing factors influence cellular behaviors, then present microfluidic-chip-based exemplary application for cancer models and stem cell differentiation.

The mechanisms underlying endosomal trafficking have been mostly dissected in yeast and mammalian tissue culture cells. Here, we review recent advances in the understanding of the role of endosomal trafficking in Drosophila epithelial cells. We focus on endosomal pathways that control cell polarization, cell growth, cell fate and epithelial cell rearrangement. We expect that mechanistic studies in mammalian cells and functional studies in invertebrates will continue to synergize to provide a comprehensive view of the role of endosomal trafficking in epithelial tissue organization and functions.

Hydrogel micropatterns of 10 approximately 200 microm in width were introduced during the polymerization of 2-acrylamido-2-methyl-propane sulfonic acid sodium salt (NaAMPS) on the surface of polyacrylamide (PAAm) gel. Behaviors of endothelial cells on the micropatterned PNaAMPS/PAAm gel surfaces were studied. Cells selectively proliferate on micropatterned PNaAMPS surface but not on PAAm surface, which requires no modification with any cell adhesive proteins or peptides. We found that decrease of the width of the micropatterns could increase the degree of anisotropic spreading of cells and the degree of cell orientation. These results demonstrated that the topographical micropatterns of hydrogel could control cell behaviors.

Mastering the interaction between cells and extracellular environment is a fundamental prerequisite in order to engineer functional biomaterial interfaces able to instruct cells with specific commands. Such advanced biomaterials might find relevant application in prosthesis design, tissue engineering, diagnostics and stem cell biology. Because of the highly complex, dynamic, and multifaceted context, a thorough understanding of the cell-material crosstalk has not been achieved yet; however, a variety of material features including biological cues, topography, and mechanical properties have been proved to impact the strength and the nature of the cell-material interaction, eventually affecting cell fate and functions. Although the nature of these three signals may appear very different, they are equated by their participation in the same material-cytoskeleton crosstalk pathway as they regulate cell adhesion events. In this work we present recent and relevant findings on the material-induced cell responses, with a particular emphasis on how the presentation of biochemical/biophysical signals modulates cell behavior. Finally, we summarize and discuss the literature data to draw out unifying elements concerning cell recognition of and reaction to signals displayed by material surfaces.

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch), pH value and the concentration of dissolved oxygen (DO) are key parameters to monitor and control cell growth in cultivation studies. Reliable, robust and accurate methods to measure these parameters in cultivation systems in real time guarantee high product yield and quality. This mini-review summarises the current state of the art of pH and DO sensors that are applied to bioprocesses from millilitre to benchtop scale by means of a short introduction on measuring principles and selected applications. Special emphasis is placed on single-use bioreactors, which have been increasingly employed in bioprocess development and production in recent years. Working principles, applications and the particular requirements of sensors in these cultivation systems are given. In such processes, optical sensors for pH and DO are often preferred to electrochemical probes, as they allow semi-invasive measurements and can be miniaturised to micrometre scale or lower. In addition, selected measuring principles of novel sensing technologies for pH and DO are discussed. These include solid-state sensors and miniaturised devices that are not yet commercially available, but show promising characteristics for possible use in bioprocesses in the near future.

Silica formation in biological systems (biosilicification) has been intensively studied for synthesizing inorganic materials such as silica and titania under biocompatible conditions. Inspired by biosilicification, biocompatible strategies have been developed to fabricate silica thin films on the surfaces of solid substrates such as flat wafers and micro/nanoparticles. In the search for biological applications, these strategies have been applied to cellular surfaces to coat living cells with silica or titania thin films while maintaining cell viability, and it was found that the inorganic coat is beneficial for the protection of living cells and to control cell division. This Microreview focuses on bio-inspired approaches to the formation of silica thin films on solid substrates and cellular surfaces, and includes the bio-inspired formation of other inorganic thin films that have been formed by bio-inspired silicification. The current status and future prospects of this field are also discussed.

The recirculation of leachate is a common strategy to accelerate the decomposition of municipal solid waste in landfills. In this study, leachates from a conventional landfill cell without supplemental liquid addition (Control cell), a new landfill area that had a piping network installed as waste was being placed (As-Built cell), and a conventional landfill that was modified to allow for the recirculation of liquids (Retrofit cell) were monitored at the outer loop landfill bioreactor (OLLB) in Louisville, Kentucky. In general, leachates from the Retrofit cells were statistically different from leachates from the As-Built and Control cells. This is likely because the waste in Retrofit cells was about 6 years old when liquids were first introduced and the waste had already reached a more mature state prior to supplemental liquids addition. Based on time series data, the Retrofit cells, which received nitrified leachate, did not show signs of accelerated waste decomposition based on the leachate che...

The success of polymer coatings for biomedical applications is undeniable. Among the very successful examples are poly(dopamine) (PDA) films due to their simplicity in deposition and beneficial interaction with biomolecules and cells. The aim of this review is to highlight the findings and achievement of PDA in nanomedicine since 2011. We discuss the progress that has been made to elucidate the structure of PDA and novel aspects considering the assembly of PDA-based films on diverse substrates. We highlight the newest results considering the biological evaluation PDA-based coatings to control cell behavior and the use of PDA in biosensing. The popularity of PDA remains unchanged, but the research efforts start to be consolidated toward more specific aims and clinical applications.

Dynamic reorganization of a cell's local microenvironment has been shown to critically alter migration, adhesion, and morphological behaviors in vivo during development, wound healing, and disease. While static microenvironments with patterned topographies, stiffness variations, or chemical gradients have been used to characterize cell responses in vitro, they are incapable of capturing the dynamic functionality of extracellular matrix naturally seen in the body. Here, we use a thermally responsive class of materials, shape memory polymers (SMPs), to dynamically manipulate the topographical environment cells experience. By providing physical manipulation of the microenvironment, we demonstrate the ability to control cell migratory behavior in response to a dynamic topographical change provided by SMPs.

The small GTPase Ras is involved in a multitude of cellular signaling pathways that culminate in changes in transcription levels to control cell differentiation, growth, and apoptosis. The three ma...