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1.
Nat Commun ; 11(1): 4434, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895393

RESUMO

Neisseria meningitidis serogroup A capsular polysaccharide (MenA CPS) consists of (1 → 6)-2-acetamido-2-deoxy-α-D-mannopyranosyl phosphate repeating units, O-acetylated at position C3 or C4. Glycomimetics appear attractive to overcome the CPS intrinsic lability in physiological media, due to cleavage of the phosphodiester bridge, and to develop a stable vaccine with longer shelf life in liquid formulation. Here, we generate a series of non-acetylated carbaMenA oligomers which are proven more stable than the CPS. An octamer (DP8) inhibits the binding of a MenA specific bactericidal mAb and polyclonal serum to the CPS, and is selected for further in vivo testing. However, its CRM197 conjugate raises murine antibodies towards the non-acetylated CPS backbone, but not the natural acetylated form. Accordingly, random O-acetylation of the DP8 is performed, resulting in a structure (Ac-carbaMenA) showing improved inhibition of anti-MenA CPS antibody binding and, after conjugation to CRM197, eliciting anti-MenA protective murine antibodies, comparably to the vaccine benchmark.


Assuntos
Glicoconjugados/síntese química , Neisseria meningitidis Sorogrupo A/imunologia , Polissacarídeos Bacterianos/síntese química , Vacinas Conjugadas , Animais , Anticorpos Antibacterianos/análise , Anticorpos Neutralizantes/química , Cápsulas Bacterianas/imunologia , Biomimética/métodos , Glicoconjugados/imunologia , Camundongos , Neisseria meningitidis Sorogrupo A/química , Neisseria meningitidis Sorogrupo A/efeitos dos fármacos , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/imunologia , Vacinas Conjugadas/química , Vacinas Conjugadas/microbiologia
2.
Nat Commun ; 11(1): 4536, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913189

RESUMO

Natural musculoskeletal systems have been widely recognized as an advanced robotic model for designing robust yet flexible microbots. However, the development of artificial musculoskeletal systems at micro-nanoscale currently remains a big challenge, since it requires precise assembly of two or more materials of distinct properties into complex 3D micro/nanostructures. In this study, we report femtosecond laser programmed artificial musculoskeletal systems for prototyping 3D microbots, using relatively stiff SU-8 as the skeleton and pH-responsive protein (bovine serum albumin, BSA) as the smart muscle. To realize the programmable integration of the two materials into a 3D configuration, a successive on-chip two-photon polymerization (TPP) strategy that enables structuring two photosensitive materials sequentially within a predesigned configuration was proposed. As a proof-of-concept, we demonstrate a pH-responsive spider microbot and a 3D smart micro-gripper that enables controllable grabbing and releasing. Our strategy provides a universal protocol for directly printing 3D microbots composed of multiple materials.


Assuntos
Biomimética/métodos , Compostos de Epóxi/efeitos da radiação , Fenômenos Fisiológicos Musculoesqueléticos , Polímeros/efeitos da radiação , Robótica/métodos , Soroalbumina Bovina/efeitos da radiação , Biomimética/instrumentação , Compostos de Epóxi/química , Hidrogéis/química , Hidrogéis/efeitos da radiação , Concentração de Íons de Hidrogênio , Lasers , Polimerização/efeitos da radiação , Polímeros/química , Impressão Tridimensional , Robótica/instrumentação , Soroalbumina Bovina/química
3.
Nat Commun ; 11(1): 4283, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883967

RESUMO

Our understanding of the spatiotemporal regulation of cardiogenesis is hindered by the difficulties in modeling this complex organ currently by in vitro models. Here we develop a method to generate heart organoids from mouse embryonic stem cell-derived embryoid bodies. Consecutive morphological changes proceed in a self-organizing manner in the presence of the laminin-entactin (LN/ET) complex and fibroblast growth factor 4 (FGF4), and the resulting in vitro heart organoid possesses atrium- and ventricle-like parts containing cardiac muscle, conducting tissues, smooth muscle and endothelial cells that exhibited myocardial contraction and action potentials. The heart organoids exhibit ultrastructural, histochemical and gene expression characteristics of considerable similarity to those of developmental hearts in vivo. Our results demonstrate that this method not only provides a biomimetic model of the developing heart-like structure with simplified differentiation protocol, but also represents a promising research tool with a broad range of applications, including drug testing.


Assuntos
Matriz Extracelular/metabolismo , Fator 4 de Crescimento de Fibroblastos/metabolismo , Coração , Células-Tronco Embrionárias Murinas/metabolismo , Organoides , Potenciais de Ação , Diamino Aminoácidos/metabolismo , Animais , Biomimética/métodos , Diferenciação Celular , Linhagem Celular , Células Endoteliais , Coração/crescimento & desenvolvimento , Coração/fisiologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Contração Miocárdica , Miocárdio , Organoides/citologia , Organoides/crescimento & desenvolvimento , Organoides/ultraestrutura
4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(9): 1177-1183, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-32929913

RESUMO

Objective: To assess the effect of microfracture and biomimetic hydrogel scaffold on tendon-to-bone healing in a rabbit rotator cuff tear model. Methods: Gelatin and methacrylic anhydride were used to synthesize gelatin methacryloyl (GelMA). Then the GelMA were treated with ultraviolet rays and vacuum freeze-drying method to obtain a biomimetic hydrogel scaffold. The morphology of the scaffold was observed by gross observation and scanning electron microscope. Degradation of the scaffold was determined at different time points. Twenty-four adult New Zealand rabbits, weighting 2.8-3.5 kg and male or female, were surgically created the bilateral acute rotator cuff tear models. One shoulder was treated with microfractures on the footprint and transosseous suture (control group, n=24). The other shoulder was treated with the same way, except for putting the scaffold on the footprint before transosseous suture (experimental group, n=24). The general conditions of rabbits were observed postoperatively. Tendon-to-bone healing was evaluated by gross observation, Micro-CT, HE staining, and bio-mechanical testing at 4 and 8 weeks after operation. Results: The scaffold was white and has a porous structure with pore size of 31.7-89.9 µm, which degraded slowly in PBS solution. The degradation rate was about 95% at 18 days. All the rabbits survived to the completion of the experiment. Micro-CT showed that there was no obvious defect and re-tear at the tendon-to-bone interface in both groups. No difference was found in bone mineral density (BMD), tissue mineral density (TMD), and bone volume/total volume (BV/TV) between the two groups at 4 and 8 weeks postoperatively ( P>0.05). HE staining showed that the fibrous scar tissue was the main component at the tendon-to-bone interface in the control group at 4 and 8 weeks postoperatively; the disorderly arranged mineralized cartilage and fibrocartilage formation were observed at the tendon-to-bone interface in the experimental group at 4 weeks, and the orderly arranged cartilage formation was observed at 8 weeks. Besides, the tendon maturation scores of the experimental group were significantly higher than those of the control group at 4 and 8 weeks ( P<0.05). There was no significant difference in the ultimate load to failure and stiffness between the two groups at 4 weeks ( P>0.05); the ultimate load to failure at 8 weeks was significantly higher in the experiment group than in the control group ( t=4.162, P=0.009), and no significant difference was found in stiffness between the two groups at 8 weeks ( t=2.286, P=0.071). Conclusion: Compared with microfracture alone, microfracture combined with biomimetic hydrogel scaffold can enhance tendon-to-bone healing and improve the ultimate load to failure in rabbits.


Assuntos
Fraturas de Estresse , Lesões do Manguito Rotador , Animais , Fenômenos Biomecânicos , Biomimética , Hidrogéis , Masculino , Coelhos , Manguito Rotador , Tendões , Cicatrização
5.
Nat Commun ; 11(1): 4108, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796840

RESUMO

Replicating biological patterns is promising for designing materials with multifaceted properties. Twisted cholesteric liquid crystal patterns are found in the iridescent tessellated cuticles of many insects and a few fruits. Their accurate replication is extremely difficult since discontinuous patterns and colors must coexist in a single layer without discontinuity of the structures. Here, a solution is demonstrated by addressing striped insect cuticles with a complex twisted organization. Geometric constraints are met by controlling the thermal diffusion in a cholesteric oligomer bilayer subjected to local changes in the molecular anchoring conditions. A multicriterion comparison reveals a very high level of biomimicry. Proof-of-concept prototypes of anti-counterfeiting tags are presented. The present design involves an economy of resources and a high versatility of chiral patterns unreached by the current manufacturing techniques such as metallic layer vacuum deposition, template embossing and various forms of lithography which are limited and often prohibitively expensive.


Assuntos
Biomimética/métodos , Biofísica/métodos , Cristais Líquidos/química , Óptica e Fotônica/métodos , Animais , Insetos
6.
Nat Commun ; 11(1): 3377, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632100

RESUMO

The mammary gland is a highly vascularized tissue capable of expansion and regression during development and disease. To enable mechanistic insight into the coordinated morphogenic crosstalk between the epithelium and vasculature, we introduce a 3D microfluidic platform that juxtaposes a human mammary duct in proximity to a perfused endothelial vessel. Both compartments recapitulate stable architectural features of native tissue and the ability to undergo distinct forms of branching morphogenesis. Modeling HER2/ERBB2 amplification or activating PIK3CA(H1047R) mutation each produces ductal changes observed in invasive progression, yet with striking morphogenic and behavioral differences. Interestingly, PI3KαH1047R ducts also elicit increased permeability and structural disorganization of the endothelium, and we identify the distinct secretion of IL-6 as the paracrine cause of PI3KαH1047R-associated vascular dysfunction. These results demonstrate the functionality of a model system that facilitates the dissection of 3D morphogenic behaviors and bidirectional signaling between mammary epithelium and endothelium during homeostasis and pathogenesis.


Assuntos
Glândulas Mamárias Humanas/metabolismo , Morfogênese/genética , Mutação , Comunicação Parácrina/genética , Biomimética/métodos , Linhagem Celular , Células Cultivadas , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Endotélio Vascular/crescimento & desenvolvimento , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Glândulas Mamárias Humanas/irrigação sanguínea , Glândulas Mamárias Humanas/crescimento & desenvolvimento , Fenótipo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo
7.
Proc Natl Acad Sci U S A ; 117(30): 17727-17736, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32665441

RESUMO

Erythrocytes naturally capture certain bacterial pathogens in circulation, kill them through oxidative stress, and present them to the antigen-presenting cells (APCs) in the spleen. By leveraging this innate immune function of erythrocytes, we developed erythrocyte-driven immune targeting (EDIT), which presents nanoparticles from the surface of erythrocytes to the APCs in the spleen. Antigenic nanoparticles were adsorbed on the erythrocyte surface. By engineering the number density of adsorbed nanoparticles, (i.e., the number of nanoparticles loaded per erythrocyte), they were predominantly delivered to the spleen rather than lungs, which is conventionally the target of erythrocyte-mediated delivery systems. Presentation of erythrocyte-delivered nanoparticles to the spleen led to improved antibody response against the antigen, higher central memory T cell response, and lower regulatory T cell response, compared with controls. Enhanced immune response slowed down tumor progression in a prophylaxis model. These findings suggest that EDIT is an effective strategy to enhance systemic immunity.


Assuntos
Apresentação do Antígeno/imunologia , Antígenos/imunologia , Eritrócitos/imunologia , Imunização , Animais , Formação de Anticorpos/imunologia , Antígenos/química , Biomimética , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Feminino , Humanos , Camundongos , Nanopartículas , Baço/imunologia , Vacinação , Vacinas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
PLoS One ; 15(7): e0235808, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32722674

RESUMO

One of the central aims of synthetic biology (SB) is to better understand the mechanisms of life by trying to develop and synthesize new forms and perhaps modes of life. While the question of what is life has occupied mankind for centuries, there is a lack of empirical research examining the basic concepts of life scientists within SB themselves refer to and build on. In order to gain insights into these fundamental concepts, we conducted a qualitative interview study with scientists working in the field of SB. The aim was to gain a better understanding of the underlying understandings, principles, and characteristics of (synthetic) life on the one hand, and the entangled consequences for the conducted experiments and studies as well as the pursued scientific approaches. We identified four primarily underlying basic concepts of life which serve as a fundamental framework for current and further scientific research within SB and have implications for research questions, approaches and aims as well as for the evaluation of scientific results.


Assuntos
Biomimética , Biologia Sintética , Biomimética/métodos , Compreensão , Feminino , Humanos , Masculino , Origem da Vida , Pesquisa , Pesquisadores , Biologia Sintética/métodos
9.
Food Chem ; 333: 127483, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679415

RESUMO

The aim of the present paper was to unravel the effect of a standardized in vitro European protocol of digestion-fermentation over Ca(II)-alginate beads synthesized with sugars and biopolymers. Special emphasis on the antioxidant capacity using methods that simulate physiological conditions, short-chain fatty acids (SCFAs) production, and a detailed study of the microstructure of the gel network by SAXS at several scales (1-100 nm) were considered. Beads released high antioxidant capacity during digestion assessed by several methods, comparable to some common foods; antioxidant capacity was improved with sucrose and arabic gum inclusion in the formulation. After fermentation by gut microbiota, a ten-fold increase in the antioxidant values and an important SCFAs production were obtained, revealing the enhanced ability to produce these functional biomolecules. The microstructural analysis of Ca(II)-alginate showed an advantageous behavior: they slightly changed in oral and gastric fluids and partially dissolved their structure in intestinal fluid, where absorption occurs.


Assuntos
Alginatos/metabolismo , Antioxidantes/metabolismo , Ácidos Graxos Voláteis/biossíntese , Fermentação , Goma Arábica/química , Microesferas , Sacarose/química , Alginatos/química , Biomimética , Microbioma Gastrointestinal
10.
Food Chem ; 333: 127509, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32717715

RESUMO

Due to their antioxidant properties, polyphenols are finding novel applications in the fields of Food Technology and Functional Nutrition in the development of innovative functional food products, and in Cosmetics and Regenerative Medicine in the development of formulations for skin disorders. The added-value of polyphenols in these areas is intimately linked to the health benefits they induce which in turn is related to the permeability across the epithelial membrane, a parameter obtained through biomimetic models. This work overviews the knowledge on the interactions of polyphenols with membrane lipids in in vitro models and the underlying challenges in translating biophysical changes achieved with current oversimplified membrane models highlighting the need for improved epithelial membrane models and in turn a better knowledge of the epithelial lipidome. Improved insight into the polyphenol-lipid interactions in vivo (patho)physiological processes will open new opportunities for the exploitation of Food and Agro-Food waste products in Health-related areas.


Assuntos
Lipidômica , Lipídeos/química , Lipídeos de Membrana/química , Polifenóis/química , Animais , Biomimética , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Fluidez de Membrana
11.
Nat Commun ; 11(1): 3668, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699271

RESUMO

Restoration is becoming a vital tool to counteract coastal ecosystem degradation. Modifying transplant designs of habitat-forming organisms from dispersed to clumped can amplify coastal restoration yields as it generates self-facilitation from emergent traits, i.e. traits not expressed by individuals or small clones, but that emerge in clumped individuals or large clones. Here, we advance restoration science by mimicking key emergent traits that locally suppress physical stress using biodegradable establishment structures. Experiments across (sub)tropical and temperate seagrass and salt marsh systems demonstrate greatly enhanced yields when individuals are transplanted within structures mimicking emergent traits that suppress waves or sediment mobility. Specifically, belowground mimics of dense root mats most facilitate seagrasses via sediment stabilization, while mimics of aboveground plant structures most facilitate marsh grasses by reducing stem movement. Mimicking key emergent traits may allow upscaling of restoration in many ecosystems that depend on self-facilitation for persistence, by constraining biological material requirements and implementation costs.


Assuntos
Adaptação Fisiológica , Recuperação e Remediação Ambiental/métodos , Hydrocharitaceae/fisiologia , Áreas Alagadas , Zosteraceae/fisiologia , Plásticos Biodegradáveis , Biomimética/métodos , Ecologia/métodos , Recuperação e Remediação Ambiental/instrumentação , Florida , Países Baixos , Água do Mar , Suécia , Clima Tropical , Índias Ocidentais
12.
PLoS One ; 15(6): e0234354, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530942

RESUMO

Soft robot fabrication by casting liquid elastomer often requires multiple steps of casting or skillful manual labor. We present a novel soft robotic fabrication technique: negshell casting (negative-space eggshell casting), that reduces the steps required for fabrication by introducing 3D-printed thin-walled cores for use in casting that are meant to be left in place instead of being removed later in the fabrication process. Negshell casting consists of two types of cores: sacrificial cores (negshell cores) and structural cores. Negshell cores are designed to be broken into small pieces that have little effect on the mechanical structure of the soft robot, and can be used for creating fluidic channels and bellows for actuation. Structural cores, on the other hand, are not meant to be broken, and are for increasing the stiffness of soft robotic structures, such as endoskeletons. We describe the design and fabrication concepts for both types of cores and report the mechanical characterization of the cores embedded in silicone rubber specimens. We also present an example use-case of negshell casting for a single joint soft robotic finger, along with an experiment to demonstrate how negshell casting concepts can aid in force transmission. Finally, we present real-world usage of negshell casting in a 6 degree-of-freedom three-finger soft robotic gripper, and a demonstration of the gripper in a robotic pick-and-place task. A companion website with further details about fabrication (as well as an introduction to molding and casting for those who are unfamiliar with the terms), engineering file downloads, and experimental data is provided at https://negshell.github.io/.


Assuntos
Desenho Assistido por Computador/instrumentação , Impressão Tridimensional/instrumentação , Robótica/instrumentação , Biomimética/instrumentação , Elasticidade , Elastômeros , Desenho de Equipamento , Dedos/fisiologia , Força da Mão/fisiologia , Humanos , Fenômenos Mecânicos , Elastômeros de Silicone
13.
Nat Commun ; 11(1): 2903, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518257

RESUMO

Direct transfer of protons and electrons between two tandem reactions is still a great challenge, because overall reaction kinetics is seriously affected by diffusion rate of the proton and electron carriers. We herein report a host-guest supramolecular strategy based on the incorporation of NADH mimics onto the surface of a metal-organic capsule to encapsulate flavin analogues for catalytic biomimetic monooxygenations in conjunction with enzymes. Coupling an artificial catalysis and a natural enzymatic catalysis in the pocket of an enzyme, this host-guest catalyst-enzyme system allows direct proton and electron transport between two catalytic processes via NADH mimics for the monooxygenation of both cyclobutanones and thioethers. This host-guest approach, which involves the direct coupling of abiotic and biotic catalysts via a NADH-containing host, is quite promising compared to normal catalyst-enzyme systems, as it offers the key advantages of supramolecular catalysis in integrated chemical and biological synthetic sequences.


Assuntos
Biomimética , Oxigênio/química , Catálise , Domínio Catalítico , Cristalografia por Raios X , Transporte de Elétrons , Enzimas/química , Ligação de Hidrogênio , Íons , Cinética , Ligantes , NAD/química , Solventes/química , Zinco/química
14.
Nat Commun ; 11(1): 2924, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32522996

RESUMO

Biological membranes play pivotal roles in the cellular activities. Transmembrane proteins are the central molecules that conduct membrane-mediated biochemical functions such as signal transduction and substance transportation. Not only the molecular functions but also the supramolecular properties of the transmembrane proteins such as self-assembly, delocalization, orientation and signal response are essential for controlling cellular activities. Here we report anisotropic ligand responses of a synthetic multipass transmembrane ion channel. An unsymmetrical molecular structure allows for oriented insertion of the synthetic amphiphile to a bilayer by addition to a pre-formed membrane. Complexation with a ligand prompts ion transportation by forming a supramolecular channel, and removal of the ligand deactivates the transportation function. Biomimetic regulation of the synthetic channel by agonistic and antagonistic ligands is also demonstrated not only in an artificial membrane but also in a biological membrane of a living cell.


Assuntos
Transporte de Íons/fisiologia , Anisotropia , Biomimética , Bicamadas Lipídicas/química , Espectroscopia de Ressonância Magnética , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência
15.
Nat Commun ; 11(1): 3091, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32555159

RESUMO

Phytoalexins have attracted much attention due to their health-promoting effects and their vital role in plant health during the last years. Especially the 6a-hydroxypterocarpans glyceollin I and glyceollin II, which may be isolated from stressed soy plants, possess a broad spectrum of bioactivities such as anticancer activity and beneficial contributions against western diseases by anti-oxidative and anti-cholesterolemic effects. Aiming for a catalytic asymmetric access to these natural products, we establish the asymmetric syntheses of the natural isoflavonoids (-)-variabilin, (-)-homopterocarpin, (-)-medicarpin, (-)-3,9-dihydroxypterocarpan, and (-)-vestitol by means of an asymmetric transfer hydrogenation (ATH) reaction. We successfully adapt this pathway to the first catalytic asymmetric total synthesis of (-)-glyceollin I and (-)-glyceollin II. This eight-step synthesis features an efficient one-pot transformation of a 2'-hydroxyl-substituted isoflavone to a virtually enantiopure pterocarpan by means of an ATH and a regioselective benzylic oxidation under aerobic conditions to afford the susceptible 6a-hydroxypterocarpan skeleton.


Assuntos
Isoflavonas/metabolismo , Pterocarpanos/metabolismo , Sesquiterpenos/metabolismo , Produtos Biológicos/metabolismo , Biomimética/métodos , Regulação da Expressão Gênica de Plantas
16.
ACS Nano ; 14(6): 6383-6406, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32519842

RESUMO

The COVID-19 outbreak has fueled a global demand for effective diagnosis and treatment as well as mitigation of the spread of infection, all through large-scale approaches such as specific alternative antiviral methods and classical disinfection protocols. Based on an abundance of engineered materials identifiable by their useful physicochemical properties through versatile chemical functionalization, nanotechnology offers a number of approaches to cope with this emergency. Here, through a multidisciplinary Perspective encompassing diverse fields such as virology, biology, medicine, engineering, chemistry, materials science, and computational science, we outline how nanotechnology-based strategies can support the fight against COVID-19, as well as infectious diseases in general, including future pandemics. Considering what we know so far about the life cycle of the virus, we envision key steps where nanotechnology could counter the disease. First, nanoparticles (NPs) can offer alternative methods to classical disinfection protocols used in healthcare settings, thanks to their intrinsic antipathogenic properties and/or their ability to inactivate viruses, bacteria, fungi, or yeasts either photothermally or via photocatalysis-induced reactive oxygen species (ROS) generation. Nanotechnology tools to inactivate SARS-CoV-2 in patients could also be explored. In this case, nanomaterials could be used to deliver drugs to the pulmonary system to inhibit interaction between angiotensin-converting enzyme 2 (ACE2) receptors and viral S protein. Moreover, the concept of "nanoimmunity by design" can help us to design materials for immune modulation, either stimulating or suppressing the immune response, which would find applications in the context of vaccine development for SARS-CoV-2 or in counteracting the cytokine storm, respectively. In addition to disease prevention and therapeutic potential, nanotechnology has important roles in diagnostics, with potential to support the development of simple, fast, and cost-effective nanotechnology-based assays to monitor the presence of SARS-CoV-2 and related biomarkers. In summary, nanotechnology is critical in counteracting COVID-19 and will be vital when preparing for future pandemics.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Nanotecnologia/métodos , Pandemias , Pneumonia Viral , Betacoronavirus/genética , Betacoronavirus/imunologia , Biomimética , Simulação por Computador , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Desinfecção , Sistemas de Liberação de Medicamentos , Microbiologia Ambiental , Humanos , Imunomodulação , Máscaras , Nanomedicina , Nanotecnologia/tendências , Pandemias/prevenção & controle , Equipamento de Proteção Individual , Fotoquimioterapia , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Vacinas Virais/genética , Vacinas Virais/farmacologia
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(3): 512-518, 2020 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-32597094

RESUMO

Masticatory robots have a broad application prospect in the field of denture material tests and mandible rehabilitation. Mechanism type of temporomandibular joint structure is an important factor influencing the performance of the masticatory robot. In view of the wide application of elastic components in the field of the biomimetic robot, an elastic component was adopted to simulate the buffering characteristics of the temporomandibular joint disc and formed the elastic temporomandibular joint structure on the basis of point-contact high pair. Secondly, the influences of the elastic temporomandibular joint structure (on mechanism degree, kinematics, dynamics, etc.) were discussed. The position and velocity of the temporomandibular joint were analyzed based on geometric constraints of the joint surface, and the dynamic analysis based on the Lagrange equation was carried out. Finally, the influence of the preload and stiffness of the elastic component was analyzed by the response surface method. The results showed that the elastic temporomandibular joint structure could effectively guarantee the flexible movement and stable force of the joint. The elastic joint structure proposed in this paper further improves the biomimetic behavior of masticatory robots. It provides new ideas for the biomimetic design of viscoelastic joint discs.


Assuntos
Biomimética , Robótica , Transtornos da Articulação Temporomandibular , Humanos , Articulação Temporomandibular , Disco da Articulação Temporomandibular , Transtornos da Articulação Temporomandibular/terapia
18.
J Vis Exp ; (160)2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32597869

RESUMO

This protocol presents a method for manufacturing, control, and evaluation of the performance of a soft robot that can climb inclined flat surfaces with slopes of up to 84°. The manufacturing method is valid for the fast pneunet bending actuators in general and might, therefore, be interesting for newcomers to the field of actuator manufacturing. The control of the robot is achieved by means of a pneumatic control box that can provide arbitrary pressures and can be built by only using purchased components, a laser cutter, and a soldering iron. For the walking performance of the robot, the pressure-angle calibration plays a crucial role. Therefore, a semi-automated method for the pressure-angle calibration is presented. At high inclines (> 70°), the robot can no longer reliably fix itself to the walking plane. Therefore, the gait pattern is modified to ensure that the feet can be fixed on the walking plane.


Assuntos
Biomimética , Lagartos/anatomia & histologia , Robótica , Animais , Calibragem , Elastômeros/química , Desenho de Equipamento , Humanos , Movimento (Física)
20.
Nature ; 581(7808): 264-265, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433616
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