Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
1.
Nat Commun ; 11(1): 2105, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355158

RESUMO

3D-printing networks of droplets connected by interface bilayers are a powerful platform to build synthetic tissues in which functionality relies on precisely ordered structures. However, the structural precision and consistency in assembling these structures is currently limited, which restricts intricate designs and the complexity of functions performed by synthetic tissues. Here, we report that the equilibrium contact angle (θDIB) between a pair of droplets is a key parameter that dictates the tessellation and precise positioning of hundreds of picolitre-sized droplets within 3D-printed, multi-layer networks. When θDIB approximates the geometrically-derived critical angle (θc) of 35.3°, the resulting networks of droplets arrange in regular hexagonal close-packed (hcp) lattices with the least fraction of defects. With this improved control over droplet packing, we can 3D-print functional synthetic tissues with single-droplet-wide conductive pathways. Our new insights into 3D droplet packing permit the fabrication of complex synthetic tissues, where precisely positioned compartments perform coordinated tasks.


Assuntos
Bioengenharia/instrumentação , Bicamadas Lipídicas/química , Impressão Tridimensional , Bioengenharia/métodos , Materiais Biomiméticos/química , Cinética , Lipídeos/química , Microscopia Confocal , Temperatura , Água/química
2.
Nat Commun ; 11(1): 2183, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366821

RESUMO

Coupling myoelectric and mechanical signals during voluntary muscle contraction is paramount in human-machine interactions. Spatiotemporal differences in the two signals intrinsically arise from the muscular excitation-contraction process; however, current methods fail to deliver local electromechanical coupling of the process. Here we present the locally coupled electromechanical interface based on a quadra-layered ionotronic hybrid (named as CoupOn) that mimics the transmembrane cytoadhesion architecture. CoupOn simultaneously monitors mechanical strains with a gauge factor of ~34 and surface electromyogram with a signal-to-noise ratio of 32.2 dB. The resolved excitation-contraction signatures of forearm flexor muscles can recognize flexions of different fingers, hand grips of varying strength, and nervous and metabolic muscle fatigue. The orthogonal correlation of hand grip strength with speed is further exploited to manipulate robotic hands for recapitulating corresponding gesture dynamics. It can be envisioned that such locally coupled electromechanical interfaces would endow cyber-human interactions with unprecedented robustness and dexterity.


Assuntos
Eletromiografia/métodos , Força da Mão/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular/fisiologia , Membros Artificiais , Bioengenharia/instrumentação , Bioengenharia/métodos , Fenômenos Biomecânicos , Eletrônica Médica/instrumentação , Eletrônica Médica/métodos , Dedos/fisiologia , Antebraço/fisiologia , Mãos/fisiologia , Humanos , Desenho de Prótese/instrumentação , Desenho de Prótese/métodos
3.
ESC Heart Fail ; 6(5): 909-920, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400060

RESUMO

Despite medical advancements, the prognosis of patients with heart failure remains poor. While echocardiography and cardiac magnetic resonance imaging remain at the forefront of diagnosing and monitoring patients with heart failure, cardiac computed tomography (CT) has largely been considered to have a limited role. With the advancements in scanner design, technology, and computer processing power, cardiac CT is now emerging as a valuable adjunct to clinicians managing patients with heart failure. In the current manuscript, we review the current applications of cardiac CT to patients with heart failure and also the emerging areas of research where its clinical utility is likely to extend into the realm of treatment, procedural planning, and advanced heart failure therapy implementation.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Bioengenharia/instrumentação , Eletrofisiologia Cardíaca/instrumentação , Cardiomiopatias/patologia , Ecocardiografia/métodos , Feminino , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Humanos , Imagem por Ressonância Magnética/métodos , Imagem de Perfusão do Miocárdio/métodos , Prognóstico , Volume Sistólico/fisiologia
4.
Biomed Mater ; 14(6): 065002, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31387088

RESUMO

Additive manufacturing (AM) presents the possibility of personalized bone scaffolds with unprecedented structural and functional designs. In contrast to earlier conventional design concepts, e.g. raster-angle, a workflow was established to produce scaffolds with triply periodic minimal surface (TPMS) architecture. A core challenge is the realization of such structures using melt-extrusion based 3D printing. This study presents methods for generation of scaffold design files, finite element (FE) analysis of scaffold Young's moduli, AM of scaffolds with polycaprolactone (PCL), and a customized in vitro assay to evaluate cell migration. The reliability of FE analysis when using computer-aided designed models as input may be impeded by anomalies introduced during 3D printing. Using micro-computed tomography reconstructions of printed scaffolds as an input for numerical simulation in comparison to experimentally obtained scaffold Young's moduli showed a moderate trend (R 2 = 0.62). Interestingly, in a preliminary cell migration assay, adipose-derived mesenchymal stromal cells (AdMSC) migrated furthest on PCL scaffolds with Diamond, followed by Gyroid and Schwarz P architectures. A similar trend, but with an accelerated AdMSC migration rate, was observed for PCL scaffolds surface coated with calcium-phosphate-based apatite. We elaborate on the importance of start-to-finish integration of all steps of AM, i.e. design, engineering and manufacturing. Using such a workflow, specific biological and mechanical functionality, e.g. improved regeneration via enhanced cell migration and higher structural integrity, may be realized for scaffolds intended as temporary guiding structures for endogenous tissue regeneration.


Assuntos
Bioengenharia/instrumentação , Bioengenharia/métodos , Osso e Ossos/química , Fosfatos de Cálcio/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Adipócitos/citologia , Movimento Celular , Força Compressiva , Simulação por Computador , Desenho Assistido por Computador , Análise de Elementos Finitos , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Poliésteres/química , Polímeros/química , Porosidade , Impressão Tridimensional , Regeneração , Estresse Mecânico , Propriedades de Superfície , Microtomografia por Raio-X
5.
Nat Commun ; 10(1): 1651, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30971693

RESUMO

Functional interfaces between electronics and biological matter are essential to diverse fields including health sciences and bio-engineering. Here, we report the discovery of spontaneous (no external energy input) hydrogen transfer from biological glucose reactions into SmNiO3, an archetypal perovskite quantum material. The enzymatic oxidation of glucose is monitored down to ~5 × 10-16 M concentration via hydrogen transfer to the nickelate lattice. The hydrogen atoms donate electrons to the Ni d orbital and induce electron localization through strong electron correlations. By enzyme specific modification, spontaneous transfer of hydrogen from the neurotransmitter dopamine can be monitored in physiological media. We then directly interface an acute mouse brain slice onto the nickelate devices and demonstrate measurement of neurotransmitter release upon electrical stimulation of the striatum region. These results open up avenues for use of emergent physics present in quantum materials in trace detection and conveyance of bio-matter, bio-chemical sciences, and brain-machine interfaces.


Assuntos
Bioengenharia/instrumentação , Técnicas Biossensoriais/instrumentação , Compostos de Cálcio/química , Glucose Oxidase/metabolismo , Óxidos/química , Titânio/química , Animais , Interfaces Cérebro-Computador , Corpo Estriado/metabolismo , Estimulação Elétrica/instrumentação , Eletrodos , Eletrônica , Elétrons , Glucose/química , Glucose/metabolismo , Hidrogênio/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Dinâmica Molecular , Neurotransmissores/metabolismo , Oxirredução
6.
IEEE Trans Biomed Eng ; 66(1): 111-118, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29993416

RESUMO

Cell patterning methods have been previously reported for cell culture. However, these methods use inclusions or devices that are not used in general cell culture and that might affect cell functionality. Here, we report a cell patterning method that can be conducted on a general cell culture dish without any inclusions by employing a resonance vibration of a disk-shaped ultrasonic transducer located under the dish. A resonance vibration with a single nodal circle patterned C2C12 myoblasts into a circular shape on the dish with 10-min exposure of the vibration with maximum peak-peak amplitude of 10 µm[Formula: see text]. Furthermore, the relationship between the amplitude distribution of the transducer and the cell density in the patterned sample could be expressed as a linear function, and there was a clear threshold of amplitude for cell adhesion. To evaluate the cell function of the patterned cells, we conducted proliferation and protein assays at 120-h culture after patterning. Our results showed that the cell proliferation rate did not decrease and the expression of cellular proteins was unchanged. Thus, we conclude, this method can successfully pattern cells in the clinically ubiquitous culture dish, while maintaining cell functionality.


Assuntos
Bioengenharia , Técnicas de Cultura de Células/instrumentação , Ultrassom/instrumentação , Animais , Bioengenharia/instrumentação , Bioengenharia/métodos , Adesão Celular/fisiologia , Técnicas de Cultura de Células/métodos , Linhagem Celular , Desenho de Equipamento , Camundongos , Pressão , Transdutores
7.
Biomaterials ; 198: 78-94, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30201502

RESUMO

Bioengineered tissues have become increasingly more sophisticated owing to recent advancements in the fields of biomaterials, microfabrication, microfluidics, genetic engineering, and stem cell and developmental biology. In the coming years, the ability to engineer artificial constructs that accurately mimic the compositional, architectural, and functional properties of human tissues, will profoundly impact the therapeutic and diagnostic aspects of the healthcare industry. In this regard, bioengineered cardiac tissues are of particular importance due to the extremely limited ability of the myocardium to self-regenerate, as well as the remarkably high mortality associated with cardiovascular diseases worldwide. As novel microphysiological systems make the transition from bench to bedside, their implementation in high throughput drug screening, personalized diagnostics, disease modeling, and targeted therapy validation will bring forth a paradigm shift in the clinical management of cardiovascular diseases. Here, we will review the current state of the art in experimental in vitro platforms for next generation diagnostics and therapy validation. We will describe recent advancements in the development of smart biomaterials, biofabrication techniques, and stem cell engineering, aimed at recapitulating cardiovascular function at the tissue- and organ levels. In addition, integrative and multidisciplinary approaches to engineer biomimetic cardiovascular constructs with unprecedented human and clinical relevance will be discussed. We will comment on the implementation of these platforms in high throughput drug screening, in vitro disease modeling and therapy validation. Lastly, future perspectives will be provided on how these biomimetic platforms will aid in the transition towards patient centered diagnostics, and the development of personalized targeted therapeutics.


Assuntos
Bioengenharia/instrumentação , Biomimética/instrumentação , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/patologia , Avaliação Pré-Clínica de Medicamentos/instrumentação , Animais , Materiais Biocompatíveis/química , Bioengenharia/métodos , Biomimética/métodos , Doenças Cardiovasculares/diagnóstico , Descoberta de Drogas/instrumentação , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Desenho de Equipamento , Humanos , Dispositivos Lab-On-A-Chip
8.
Biomaterials ; 198: 49-62, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30007472

RESUMO

The pathophysiology of type 1 diabetes is a complex process involving tightly controlled microenvironments, a number of highly specific immune cell - islet cell interactions, and the eventual breaking of immune tolerance leading to beta cell death. Modeling this process can provide researchers with powerful insights into how and when to best provide treatment, but has proven difficult to accurately model due to its complex nature and differences between animal models and humans. Much progress has been made in determining the genetic, molecular, and cellular mechanisms of type 1 diabetes, yet translating that knowledge to clinical treatments remains challenging. Thus, there exists a capabilities gap between understanding the disease pathophysiology and engineering effective clinical treatment strategies. Biomimetic modeling of human type 1 diabetes is a valuable tool to study and manipulate islet function and can be employed to address immunological aspects of type 1 diabetes. This article will review recent advances in this field, and will suggest ways to synergize systems to model and observe the pathophysiology of autoimmune diabetes with bioengineered therapeutic strategies.


Assuntos
Microambiente Celular , Diabetes Mellitus Tipo 1/patologia , Ilhotas Pancreáticas/patologia , Animais , Materiais Biocompatíveis/química , Bioengenharia/instrumentação , Bioengenharia/métodos , Materiais Biomiméticos/química , Desenho de Equipamento , Humanos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
9.
Mo Med ; 115(4): 368-373, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30228770

RESUMO

3D printing technology evolved in the 1980s, but has made great strides in the last decade from both a cost and accessibility standpoint. While most printers are employed for commercial uses, medical 3D printing is a growing application which serves to aid physicians in the diagnosis, therapeutic planning, and potentially the treatment of patients with complex diseases. In this article we will delineate the types of printers available to the consumer, the various materials which can be utilized, and potential applications of 3D models in the healthcare field.


Assuntos
Bioengenharia/instrumentação , Desenho Assistido por Computador/tendências , Diagnóstico por Imagem/tendências , Impressão Tridimensional/tendências , Bioengenharia/tendências , Humanos , Imageamento Tridimensional
10.
Methods Mol Biol ; 1835: 217-228, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30109655

RESUMO

Solid-state fermentation (SSF) has been largely employed during the last three decades to produce different biomolecules of industrial interest, particularly enzymes. Through the use of agroindustrial wastes as SSF substrates, an economic process of lipases production can be achieved. In this chapter we describe a comprehensive SSF method for producing an economical preparation of Rhizomucor miehei lipase, employing sugarcane bagasse and used vegetal oil as substrates. To demonstrate the usefulness of the lipase produced by this method, we utilized directly the dried fermented solid, as a heterogeneous biocatalyst for the ethanolysis of different fats and oils. Final ethyl ester conversions (>90%, 24 h) were similar with those obtained using a commercial immobilized Rhizomucor miehei lipase at our best conditions. In this work we demonstrated that SSF is an easy and economical method for the production of lipases that can be used directly as heterogeneous biocatalysts for biodiesel production, employing low-cost feedstocks.


Assuntos
Bioengenharia , Fermentação , Lipase/biossíntese , Bioengenharia/instrumentação , Bioengenharia/métodos , Biocombustíveis , Catálise , Concentração de Íons de Hidrogênio , Hidrólise , Cinese , Lipase/isolamento & purificação , Temperatura
11.
J Biomech Eng ; 140(9)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029232

RESUMO

Delivery of biological fluids, such as surfactant solutions, into lungs is a major strategy to treat respiratory disorders including respiratory distress syndrome that is caused by insufficient or dysfunctional natural lung surfactant. The instilled solution forms liquid plugs in lung airways. The plugs propagate downstream in airways by inspired air or ventilation, continuously split at airway bifurcations to smaller daughter plugs, simultaneously lose mass from their trailing menisci, and eventually rupture. A uniform distribution of the instilled biofluid in lung airways is expected to increase the treatments success. The uniformity of distribution of instilled liquid in the lungs greatly depends on the splitting of liquid plugs between daughter airways, especially in the first few generations from which airways of different lobes of lungs emerge. To mechanistically understand this process, we developed a bioengineering approach to computationally design three-dimensional bifurcating airway models using morphometric data of human lungs, fabricate physical models, and examine dynamics of liquid plug splitting. We found that orientation of bifurcating airways has a major effect on the splitting of liquid plugs between daughter airways. Changing the relative gravitational orientation of daughter tubes with respect to the horizontal plane caused a more asymmetric splitting of liquid plugs. Increasing the propagation speed of plugs partially counteracted this effect. Using airway models of smaller dimensions reduced the asymmetry of plug splitting. This work provides a step toward developing delivery strategies for uniform distribution of therapeutic fluids in the lungs.


Assuntos
Bioengenharia/instrumentação , Hidrodinâmica , Pulmão/anatomia & histologia , Pulmão/metabolismo , Fenômenos Mecânicos , Fenômenos Biomecânicos , Pulmão/fisiologia
12.
Chem Soc Rev ; 47(17): 6486-6504, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-29938722

RESUMO

Silks are natural fibrous protein polymers that are spun by silkworms and spiders. Among silk variants, there has been increasing interest devoted to the silkworm silk of B. mori, due to its availability in large quantities along with its unique material properties. Silk fibroin can be extracted from the cocoons of the B. mori silkworm and combined synergistically with other biomaterials to form biopolymer composites. With the development of recombinant DNA technology, silks can also be rationally designed and synthesized via genetic control. Silk proteins can be processed in aqueous environments into various material formats including films, sponges, electrospun mats and hydrogels. The versatility and sustainability of silk-based materials provides an impressive toolbox for tailoring materials to meet specific applications via eco-friendly approaches. Historically, silkworm silk has been used by the textile industry for thousands of years due to its excellent physical properties, such as lightweight, high mechanical strength, flexibility, and luster. Recently, due to these properties, along with its biocompatibility, biodegradability and non-immunogenicity, silkworm silk has become a candidate for biomedical utility. Further, the FDA has approved silk medical devices for sutures and as a support structure during reconstructive surgery. With increasing needs for implantable and degradable devices, silkworm silk has attracted interest for electronics, photonics for implantable yet degradable medical devices, along with a broader range of utility in different device applications. This Tutorial review summarizes and highlights recent advances in the use of silk-based materials in bio-nanotechnology, with a focus on the fabrication and functionalization methods for in vitro and in vivo applications in the field of tissue engineering, degradable devices and controlled release systems.


Assuntos
Materiais Biocompatíveis/química , Bioengenharia/métodos , Bombyx/química , Nanoestruturas/química , Nanotecnologia/métodos , Seda/química , Animais , Materiais Biocompatíveis/metabolismo , Bioengenharia/instrumentação , Bombyx/genética , Bombyx/metabolismo , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Desenho de Equipamento , Engenharia Genética/instrumentação , Engenharia Genética/métodos , Humanos , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Seda/genética , Seda/metabolismo , Seda/ultraestrutura , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
13.
Acc Chem Res ; 51(4): 829-838, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29561583

RESUMO

Multifunctional devices for modulation and probing of neuronal activity during free behavior facilitate studies of functions and pathologies of the nervous system. Probes composed of stiff materials, such as metals and semiconductors, exhibit elastic and chemical mismatch with the neural tissue, which is hypothesized to contribute to sustained tissue damage and gliosis. Dense glial scars have been found to encapsulate implanted devices, corrode their surfaces, and often yield poor recording quality in long-term experiments. Motivated by the hypothesis that reducing the mechanical stiffness of implanted probes may improve their long-term reliability, a variety of probes based on soft materials have been developed. In addition to enabling electrical neural recording, these probes have been engineered to take advantage of genetic tools for optical neuromodulation. With the emergence of optogenetics, it became possible to optically excite or inhibit genetically identifiable cell types via expression of light-sensitive opsins. Optogenetics experiments often demand implantable multifunctional devices to optically stimulate, deliver viral vectors and drugs, and simultaneously record electrophysiological signals from the specified cells within the nervous system. Recent advances in microcontact printing and microfabrication techniques have equipped flexible probes with microscale light-emitting diodes (µLEDs), waveguides, and microfluidic channels. Complementary to these approaches, fiber drawing has emerged as a scalable route to integration of multiple functional features within miniature and flexible neural probes. The thermal drawing process relies on the fabrication of macroscale models containing the materials of interest, which are then drawn into microstructured fibers with predefined cross-sectional geometries. We have recently applied this approach to produce fibers integrating conductive electrodes for extracellular recording of single- and multineuron potentials, low-loss optical waveguides for optogenetic neuromodulation, and microfluidic channels for drug and viral vector delivery. These devices allowed dynamic investigation of the time course of opsin expression across multiple brain regions and enabled pairing of optical stimulation with local pharmacological intervention in behaving animals. Neural probes designed to interface with the spinal cord, a viscoelastic tissue undergoing repeated strain during normal movement, rely on the integration of soft and flexible materials to avoid injury and device failure. Employing soft substrates, such as parylene C and poly-(dimethylsiloxane), for electrode and µLED arrays permitted stimulation and recording of neural activity on the surface of the spinal cord. Similarly, thermally drawn flexible and stretchable optoelectronic fibers that resemble the fibrous structure of the spinal cord were implanted without any significant inflammatory reaction in the vicinity of the probes. These fibers enabled simultaneous recording and optogenetic stimulation of neural activity in the spinal cord. In this Account, we review the applications of multifunctional fibers and other integrated devices for optoelectronic probing of neural circuits and discuss engineering directions that may facilitate future studies of nerve repair and accelerate the development of bioelectronic medical devices.


Assuntos
Bioengenharia/instrumentação , Neurociências/instrumentação , Fibras Ópticas , Animais , Eletrônica Médica , Humanos
14.
Development ; 145(5)2018 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29519889

RESUMO

The advent of human induced pluripotent stem cells (iPSCs) presents unprecedented opportunities to model human diseases. Differentiated cells derived from iPSCs in two-dimensional (2D) monolayers have proven to be a relatively simple tool for exploring disease pathogenesis and underlying mechanisms. In this Spotlight article, we discuss the progress and limitations of the current 2D iPSC disease-modeling platform, as well as recent advancements in the development of human iPSC models that mimic in vivo tissues and organs at the three-dimensional (3D) level. Recent bioengineering approaches have begun to combine different 3D organoid types into a single '4D multi-organ system'. We summarize the advantages of this approach and speculate on the future role of 4D multi-organ systems in human disease modeling.


Assuntos
Técnicas de Cultura de Células/métodos , Doença , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Modelos Teóricos , Organoides/citologia , Bioengenharia/instrumentação , Bioengenharia/métodos , Materiais Biomiméticos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/tendências , Diferenciação Celular , Matriz Extracelular/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Tecidos Suporte
15.
Hand (N Y) ; 13(1): 23-32, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28718314

RESUMO

BACKGROUND: The alteration of forces across joints can result in instability and subsequent disability. Previous methods of force measurements such as pressure-sensitive films, load cells, and pressure-sensing transducers have been utilized to estimate biomechanical forces across joints and more recent studies have utilized a nondestructive method that allows for assessment of joint forces under ligamentous restraints. METHODS: A comprehensive review of the literature was performed to explore the numerous biomechanical methods utilized to estimate intra-articular forces. RESULTS: Methods of biomechanical force measurements in joints are reviewed. CONCLUSIONS: Methods such as pressure-sensitive films, load cells, and pressure-sensing transducers require significant intra-articular disruption and thus may result in inaccurate measurements, especially in small joints such as those within the wrist and hand. Non-destructive methods of joint force measurements either utilizing distraction-based joint reaction force methods or finite element analysis may offer a more accurate assessment; however, given their recent inception, further studies are needed to improve and validate their use.


Assuntos
Fenômenos Biomecânicos/fisiologia , Pressão , Articulação do Punho/fisiologia , Bioengenharia/instrumentação , Humanos , Transdutores de Pressão
17.
FEMS Yeast Res ; 17(7)2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961766

RESUMO

Our ability to rewire cellular metabolism for the sustainable production of chemicals, fuels and therapeutics based on microbial cell factories has advanced rapidly during the last two decades. Especially the speed and precision by which microbial genomes can be engineered now allow for more advanced designs to be implemented and tested. However, compared to the methods developed for engineering cell factories, the methods developed for testing the performance of newly engineered cell factories in high throughput are lagging far behind, which consequently impacts the overall biomanufacturing process. For this purpose, there is a need to develop new techniques for screening and selection of best-performing cell factory designs in multiplex. Here we review the current status of the sourcing, design and engineering of biosensors derived from allosterically regulated transcription factors applied to the biotechnology work-horse budding yeast Saccharomyces cerevisiae. We conclude by providing a perspective on the most important challenges and opportunities lying ahead in order to harness the full potential of biosensor development for increasing both the throughput of cell factory development and robustness of overall bioprocesses.


Assuntos
Reatores Biológicos , Técnicas Biossensoriais , Fatores de Transcrição/metabolismo , Leveduras/genética , Leveduras/metabolismo , Bioengenharia/instrumentação , Bioengenharia/métodos , Expressão Gênica , Genes Reporter , Proteínas Repressoras/metabolismo , Transativadores/metabolismo
18.
J Vis Exp ; (125)2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28745624

RESUMO

Biological machines often referred to as biorobots, are living cell- or tissue-based devices that are powered solely by the contractile activity of living components. Due to their inherent advantages, biorobots are gaining interest as alternatives to traditional fully artificial robots. Various studies have focused on harnessing the power of biological actuators, but only recently studies have quantitatively characterized the performance of biorobots and studied their geometry to enhance functionality and efficiency. Here, we demonstrate the development of a self-stabilizing swimming biorobot that can maintain its pitch, depth, and roll without external intervention. The design and fabrication of the PDMS scaffold for the biological actuator and biorobot followed by the functionalization with fibronectin is described in this first part. In the second part of this two-part article, we detail the incorporation of cardiomyocytes and characterize the biological actuator and biorobot function. Both incorporate a base and tail (cantilever) which produce fin-based propulsion. The tail is constructed with soft lithography techniques using PDMS and laser engraving. After incorporating the tail with the device base, it is functionalized with a cell adhesive protein and seeded confluently with cardiomyocytes. The base of the biological actuator consists of a solid PDMS block with a central glass bead (acts as a weight). The base of the biorobot consists of two composite PDMS materials, Ni-PDMS and microballoon-PDMS (MB-PDMS). The nickel powder (in Ni-PDMS) allows magnetic control of the biorobot during cells seeding and stability during locomotion. Microballoons (in MB-PDMS) decrease the density of MB-PDMS, and enable the biorobot to float and swim steadily. The use of these two materials with different mass densities, enabled precise control over the weight distribution to ensure a positive restoration force at any angle of the biorobot. This technique produces a magnetically controlled self-stabilizing swimming biorobot.


Assuntos
Bioengenharia/métodos , Materiais Biomiméticos , Contração Muscular , Miócitos Cardíacos/metabolismo , Robótica/métodos , Bioengenharia/instrumentação , Miócitos Cardíacos/citologia , Robótica/instrumentação
19.
Nat Nanotechnol ; 12(9): 907-913, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28737748

RESUMO

Thin-film electronic devices can be integrated with skin for health monitoring and/or for interfacing with machines. Minimal invasiveness is highly desirable when applying wearable electronics directly onto human skin. However, manufacturing such on-skin electronics on planar substrates results in limited gas permeability. Therefore, it is necessary to systematically investigate their long-term physiological and psychological effects. As a demonstration of substrate-free electronics, here we show the successful fabrication of inflammation-free, highly gas-permeable, ultrathin, lightweight and stretchable sensors that can be directly laminated onto human skin for long periods of time, realized with a conductive nanomesh structure. A one-week skin patch test revealed that the risk of inflammation caused by on-skin sensors can be significantly suppressed by using the nanomesh sensors. Furthermore, a wireless system that can detect touch, temperature and pressure is successfully demonstrated using a nanomesh with excellent mechanical durability. In addition, electromyogram recordings were successfully taken with minimal discomfort to the user.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletromiografia/instrumentação , Eletrônica Médica/instrumentação , Nanoestruturas/química , Pele , Adulto , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/química , Bioengenharia/instrumentação , Condutividade Elétrica , Gases/química , Humanos , Inflamação/etiologia , Pessoa de Meia-Idade , Nanoestruturas/efeitos adversos , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Permeabilidade , Pele/metabolismo , Adulto Jovem
20.
Integr Biol (Camb) ; 9(8): 678-686, 2017 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-28581556

RESUMO

Schwann cells (SCs) contribute to the regulation of axonal conduction in a myelin-dependent and -independent manner. However, due to the lack of investigative techniques that are able to record axonal conduction under conditions that control the proliferation of specific SC types, little is known about the extent to which myelinated SCs (mSCs) and unmyelinated SCs (umSCs) modulate axonal conduction. In this study, a microtunnel-electrode approach was applied to a neuron/SC co-culture technique. Rat dorsal root ganglion neurons and SCs were co-cultured in a microtunnel-electrode device, which enabled recording of the conduction delay in multiple axons passing through microtunnels. Despite the absence of nuclei in the microtunnel when SCs were eliminated, cultured cells were densely packed and expressed S100 beta (an SC marker) at a rate of 96% in neuron/SC co-culture, indicating that SCs migrated into the microtunnel. In addition, supplementation with ascorbic acid after 6 days in vitro (DIV) successfully induced myelination from 22 DIV. Activity recording experiments indicated that the conduction delay decreased with culture length from 17 DIV in the neuron/SC co-culture but not in neuron monoculture. Interestingly, the SC-modulated shortening of conduction delay was attenuated at 17 DIV and 22 DIV by supplementing the culture medium with ascorbic acid and, at the same time, suppressing SC proliferation, suggesting that immature umSCs increased axonal conduction velocity in a cell density-dependent manner before the onset of myelination. These results suggest that this method is an effective tool for investigating the contributions of mSCs or umSCs to the regulation of axonal conduction.


Assuntos
Técnicas de Cocultura/métodos , Condução Nervosa/fisiologia , Nervos Periféricos/citologia , Nervos Periféricos/fisiologia , Células de Schwann/fisiologia , Animais , Axônios/fisiologia , Bioengenharia/instrumentação , Bioengenharia/métodos , Células Cultivadas , Técnicas de Cocultura/instrumentação , Desenho de Equipamento , Gânglios Espinais/citologia , Gânglios Espinais/fisiologia , Bainha de Mielina/fisiologia , Neurogênese/fisiologia , Neurônios/fisiologia , Ratos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...