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1.
Proc Natl Acad Sci U S A ; 117(2): 895-901, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31882450

RESUMO

Emerging and reemerging viruses are responsible for a number of recent epidemic outbreaks. A crucial step in predicting and controlling outbreaks is the timely and accurate characterization of emerging virus strains. We present a portable microfluidic platform containing carbon nanotube arrays with differential filtration porosity for the rapid enrichment and optical identification of viruses. Different emerging strains (or unknown viruses) can be enriched and identified in real time through a multivirus capture component in conjunction with surface-enhanced Raman spectroscopy. More importantly, after viral capture and detection on a chip, viruses remain viable and get purified in a microdevice that permits subsequent in-depth characterizations by various conventional methods. We validated this platform using different subtypes of avian influenza A viruses and human samples with respiratory infections. This technology successfully enriched rhinovirus, influenza virus, and parainfluenza viruses, and maintained the stoichiometric viral proportions when the samples contained more than one type of virus, thus emulating coinfection. Viral capture and detection took only a few minutes with a 70-fold enrichment enhancement; detection could be achieved with as little as 102 EID50/mL (50% egg infective dose per microliter), with a virus specificity of 90%. After enrichment using the device, we demonstrated by sequencing that the abundance of viral-specific reads significantly increased from 4.1 to 31.8% for parainfluenza and from 0.08 to 0.44% for influenza virus. This enrichment method coupled to Raman virus identification constitutes an innovative system that could be used to quickly track and monitor viral outbreaks in real time.


Assuntos
Técnicas Microbiológicas/métodos , Virologia/métodos , Viroses/diagnóstico , Vírus/isolamento & purificação , Humanos , Vírus da Influenza A/isolamento & purificação , Técnicas Microbiológicas/instrumentação , Microtecnologia/métodos , Nanotubos de Carbono , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Respirovirus/isolamento & purificação , Rhinovirus/isolamento & purificação , Sensibilidade e Especificidade , Dióxido de Silício , Análise Espectral Raman/métodos , Coloração e Rotulagem , Vírion , Virologia/instrumentação , Viroses/virologia , Vírus/genética
2.
Methods Mol Biol ; 2041: 233-241, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646493

RESUMO

Imbalance in extracellular ATP levels in brain tissue has been suggested as a triggering factor for several neurological disorders. Here, we describe the most sensitive and reliable technique for monitoring the ATP levels in mice cerebrospinal samples collected by cisterna magna puncture technique and quantified using a microplate reader.


Assuntos
Trifosfato de Adenosina/líquido cefalorraquidiano , Encéfalo/metabolismo , Cisterna Magna/metabolismo , Luciferases/metabolismo , Microtecnologia/métodos , Fotometria/métodos , Animais , Cisterna Magna/cirurgia , Camundongos
3.
Int J Nanomedicine ; 14: 9019-9029, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819416

RESUMO

Background: Over recent years, green chemistry procedures have been developed to synthesize nanoparticles in eco-friendlier and less expensive ways. These procedures use natural sources such as bacteria, fungi, yeast, plants, actinomycetes, algae, or cyanobacteria, or use biomolecules such as proteins, vitamins, or pigments instead of chemical materials to fabricate salt precursors into nanoparticles. Methodology: In the current investigation, we developed an effective, inexpensive, nontoxic method to synthesize silver nanoparticles (SNPs) using the cellular extract of a novel strain of cyanobacterium, Nostoc sp. Bahar M. SNPs were characterized using ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The antitumor properties of the biogenic SNPs were tested against Caco-2 cells using a cell proliferation assay and inverted light microscopy. Results: The new strain Nostoc sp. Bahar M was able to fabricate small SNPs from silver nitrate through an eco-friendly and inexpensive biosynthesis process. SNPs synthesis was accompanied by a color transformation from pale yellow to dark brown. Ultraviolet spectroscopy showed an absorption peak at 403 nm, confirming SNPs formation. X-ray diffraction analysis indicated that the SNPs had a face-centered cubic crystalline structure. Fourier-transform infrared spectroscopy was used to identify a protein that may play an important role in SNPs biosynthesis. Scanning and transmission electron micrographs showed that the SNPs were uniformly distributed and spherical in shape, with an average diameter of 14.9 nm. Cytotoxicity assays showed that SNPs exhibited a significant dose-dependent cytotoxic activity against human colon cancer cells with an IC50 of 150 µg/mL. Conclusion: Nostoc sp. Bahar M provided an eco-friendly route for fabricating SNPs, which have cytotoxic activity toward Caco-2 cells.


Assuntos
Antineoplásicos/farmacologia , Nanopartículas Metálicas/química , Microtecnologia/métodos , Nostoc/metabolismo , Prata/química , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/ultraestrutura , Filogenia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Int J Nanomedicine ; 14: 6631-6644, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695361

RESUMO

Recent breakthroughs in nanoparticle research have led to improved drug delivery and have overcome problems associated with normal drug delivery methods. Optimizing the design of nanoparticles in terms of controlled size, shape, and surface chemistry of nanoparticles can maximize the therapeutic efficacy. To maximize therapeutic effects, advanced formulation and fabrication methods have been developed. Biomedical applications of nanoparticles produced using the new fabrication techniques, including drug delivery and molecular imaging, have been widely explored. This review highlights the simple and versatile manufacturing techniques that can be used in the development of new types of nanoparticles that have strictly controlled physiochemical properties and their multifaceted advantages in drug delivery and molecular imaging.


Assuntos
Sistemas de Liberação de Medicamentos , Microtecnologia/métodos , Imagem Molecular/métodos , Nanopartículas/química , Animais , Humanos , Nanopartículas/ultraestrutura
5.
Int J Nanomedicine ; 14: 8399-8408, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695373

RESUMO

Purpose: This work aimed to synthesize surfactant-free AuNPs for targeted delivery of plasmid DNA encoded p53 gene and to avoid conventional production method of Gold nanoparticles (AuNPs) which may adversely affect the final shape, diversity, and size due to accumulation of the formulated surfactant - gold complex to the surface. Methods: The AuNPs were fabricated using seeded-growth method with L-Cystine methyl ester hydrochloride as capping agent, then loaded with plasmid DNA encoded p53 gene. The resultant AuNPs and AuNPs-p53 complex were evaluated for physical characteristics and morphology. Confirmation of complex formation was performed using gel electrophoresis. Furthermore, the efficient delivery and cytotoxicity behavior of the encoded gene were examined on both healthy lung cells (WI38) and cancerous lung cells (A549). Results: L-cysteine methyl ester hydrochloride AuNPs showed acceptable physical characteristics (30 nm, +36.9 mv, and spherical morphology). P53 attachment to AuNPs was confirmed by gel electrophoresis. The RT-PCR proved the overexpression of p53 by the fabricated AuNPs-p53 complex. The high percentage of cell viability in normal lung cell line (WI 38) proved the safety of L-cysteine methyl ester functionalized AuNPs. Additionally, the apoptotic effect due to expression of p53 gene loaded on AuNPs was only prominent in lung cancer cell line (A549), revealing selectivity and targeting efficiency of anticancer AuNPs-p53 complex. Conclusion: AuNPs can be considered as a potential delivery system for effective transfection of plasmid DNA which can be used for successful treatment of cancer.


Assuntos
DNA/genética , Ouro/química , Nanopartículas Metálicas/química , Microtecnologia/métodos , Plasmídeos/genética , Tensoativos/química , Células A549 , Morte Celular , Sobrevivência Celular , Difusão Dinâmica da Luz , Humanos , Nanopartículas Metálicas/ultraestrutura , Proteína Supressora de Tumor p53/metabolismo
6.
Int J Nanomedicine ; 14: 7683-7694, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571871

RESUMO

Background: Nerve regeneration is important for the treatment of degenerative diseases and neurons injured by accidents. Nerve growth factor (NGF) has been previously conjugated to materials for promotion of neurogenesis. Materials and methods: Photoreactive gelatin was prepared by chemical coupling of gelatin with azidobenzoic acid (P-gel), and then NGF was immobilized on substrates in the presence or absence of micropatterned photomasks. UV irradiation induced crosslinking reactions of P-gel with itself, NGF, and the plate for immobilization. Results: By adjustment of the P-gel concentration, the nanometer-order height of micropatterns was controlled. NGF was quantitatively immobilized with increasing amounts of P-gel. Immobilized NGF induced neurite outgrowth of PC12 cells, a cell line derived from a pheochromocytoma of the rat adrenal medulla, at the same level as soluble NGF. The immobilized NGF showed higher thermal stability than the soluble NGF and was repeatedly used without loss of biological activity. The 3D structure (height of the formed micropattern) regulated the behavior of neurite guidance. As a result, the orientation of neurites was regulated by the stripe pattern width. Conclusion: The micropattern-immobilized NGF nanolayer biochemically and topologically regulated neurite formation.


Assuntos
Proteínas Imobilizadas/farmacologia , Microtecnologia/métodos , Nanopartículas/química , Fator de Crescimento Neural/farmacologia , Neuritos/metabolismo , Animais , Humanos , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Células PC12 , Estabilidade Proteica/efeitos dos fármacos , Ratos , Solubilidade , Suínos , Temperatura
7.
Molecules ; 24(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546819

RESUMO

The Hasti Afunei sarcophagus is a large Etruscan urn, made up of two chalky alabaster monoliths. Dated from the last quarter of the third century BC, it was found in 1826 in the small town of Chiusi (Tuscany- Il Colle place) by a landowner, Pietro Bonci Casuccini, who made it part of his private collection. The noble owner's collection was sold in 1865 to the Royal Museum of Palermo (today under the name of Antonino Salinas Regional Archaeological Museum), where it is still displayed. The sarcophagus is characterized by a complex iconography that is meticulously illustrated through an excellent sculptural technique, despite having subjected to anthropic degradation and numerous restorative actions during the last century. During the restoration campaign carried out between 2016 and 2017, a targeted diagnostic campaign was carried out to identify the constituent materials of the artefact, the pigments employed and the executive technique, in order to get an overall picture of conservation status and conservative criticalities. In particular, this last intervention has allowed the use of the innovative micro-sampling technique, patented by the Cultural Heritage research group of Sapienza, in order to identify the employee of lake pigments through SERS analyses. Together with this analysis, Raman and NMR technique have completed the information requested by restorers, for what concerns the wax employed as protective layers, and allowed to rebuild the conservation history of the sarcophagus. In fact, together with the identification of red ocher and yellow ocher, carbon black, Egyptian blue and madder lake, pigments compatible with the historical period of the work, modern pigments (probably green Paris, chrome orange, barium yellow, blue phtalocyanine) have been recognized, attributable with not documented intervention during the eighteenth and twentieth centuries.


Assuntos
Arqueologia , Microtecnologia/métodos , Análise Espectral Raman/métodos , Cor , Corantes/química , Imageamento Tridimensional , Itália
8.
Sensors (Basel) ; 19(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31509969

RESUMO

Food intolerance is delayed adverse food reactions which follow consumption of specific foods. The underlying mechanisms are not well understood, but food intolerance is often considered as a type 2 hypersensitivity reaction mediated by immunoglobulin G (IgG) antibody. To understand the causes of food intolerance, it is important to investigate sensitization patterns of food-specific IgGs (sIgG) in relation to dietary patterns and physical conditions. Conventional approaches to measure serological IgGs often require large volumes of serum, thus are not suitable for highly multiplexed assays. To overcome this impracticality, we developed a highly sensitive method to screen the sIgGs and other antibody isotypes against 66 antigens with minimal amount of serums. We prepared a microarray by immobilizing food antigens on activated glass slides. Human sera and their dietary information were obtained from 30 subjects. Aliquots (200 nl) of sera were analyzed against 66 food antigens in parallel. sIgG levels were determined and analyzed in relation to subjects' dietary patterns. The levels of antibody isotypes were also examined to understand the relationship between allergy and food intolerance. The developed microarray showed exceptional performances in antibody screening and demonstrated the potential to be used as an automated assay system.


Assuntos
Antígenos/análise , Alimentos , Isotipos de Imunoglobulinas/sangue , Análise em Microsséries/métodos , Microtecnologia/métodos , Sorologia , Adulto , Dieta , Feminino , Humanos , Pessoa de Meia-Idade
9.
Nat Commun ; 10(1): 3805, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444344

RESUMO

The versatile and tunable self-assembly properties of nucleic acids and engineered nucleic acid constructs make them invaluable in constructing microscale and nanoscale devices, structures and circuits. Increasing the complexity, functionality and ease of assembly of such constructs, as well as interfacing them to the macroscopic world requires a multifaceted and programmable fabrication approach that combines efficient and spatially resolved nucleic acid synthesis with multiple post-synthetic chemical and enzymatic modifications. Here we demonstrate a multi-level photolithographic patterning approach that starts with large-scale in situ surface synthesis of natural, modified or chimeric nucleic acid molecular structures and is followed by chemical and enzymatic nucleic acid modifications and processing. The resulting high-complexity, micrometer-resolution nucleic acid surface patterns include linear and branched structures, multi-color fluorophore labeling and programmable targeted oligonucleotide immobilization and cleavage.


Assuntos
Técnicas Biossensoriais/instrumentação , Microtecnologia/métodos , Ácidos Nucleicos/química , Reagentes para Ligações Cruzadas/química , Fluorescência , Luz , Conformação de Ácido Nucleico/efeitos da radiação , Ácidos Nucleicos/efeitos da radiação , Oligonucleotídeos/química , Oligonucleotídeos/efeitos da radiação , Processos Fotoquímicos/efeitos da radiação
10.
Anal Bioanal Chem ; 411(25): 6561-6573, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31444532

RESUMO

Self-propelled micromotors are micro- and nanoscale devices that move autonomously in solution by converting a specific stimulus into mechanical work. The broad scope of operations and applications along with the ultra-small dimensions have opened new possibilities to solve complex analytical challenges. Herein we give a critical overview of early developments and future prospects of such tiny moving objects for different analytical sensing and biosensing strategies. From early electrophoretic propelled nanomotors, which were limited to low viscous media, to bubble-propelled micromotors, the field has evolved into sophisticated all-in-one analytical systems with built-in sensing capabilities. Current progress for in vivo biosensing and integration into analytical instrumentation towards fully functional devices will be also covered. We hope that this review provides the reader with some general knowledge and future prospects of self-propelled micromachines as a new paradigm in analytical chemistry. Graphical abstract.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas de Química Analítica/métodos , Microtecnologia/métodos , Animais , Técnicas Biossensoriais/instrumentação , Técnicas de Química Analítica/instrumentação , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Desenho de Equipamento , Humanos , Microtecnologia/instrumentação , Nanoestruturas/química , Nanotecnologia/instrumentação , Nanotecnologia/métodos
11.
J Mater Sci Mater Med ; 30(8): 92, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388767

RESUMO

Having similar properties with natural bone, has made porous NiTi shape memory alloy (SMA) a promising material for biomedical applications. In this study porous NiTi SMA has synthesized with 30 and 40 vol.% green porosity by self propagating high temperature synthesis (SHS) from elemental Ni and Ti powders. After synthesizing, the average porosity of specimens reached to 36.8 and 49.8% for green compacts with 30 and 40 vol.% of green porosity, respectively. Combustion products were characterized by XRD, SEM, EDS and electrochemical polarization test. Although desired B2 (NiTi) phase was the dominant phase, other phases like Ti2Ni, Ni3Ti and Ni4Ti3 are found. Electrochemical polarization analysis in simulated body fluids (SBF) shows that, synthesized porous NiTi has better corrosion resistance than solid one and hydroxy apatite coating on porous NiTi worsen electrochemical corrosion resistance which is because of bioactive behavior of hydroxy apatite.


Assuntos
Ligas/síntese química , Materiais Biocompatíveis/síntese química , Temperatura Alta , Microtecnologia/métodos , Níquel/química , Polimerização , Titânio/química , Ligas/química , Materiais Biocompatíveis/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Porosidade , Pós/síntese química , Pós/química , Espectrometria por Raios X , Propriedades de Superfície , Difração de Raios X
12.
IET Nanobiotechnol ; 13(6): 565-570, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31432787

RESUMO

Carbon aerogels have attracted considerable attention in basic research and for their potential applications in many fields. Here, the fabrication of a magnetic cellulose nanofibre (CNF)/poly(vinyl alcohol) (PVA)/multiwalled carbon nanotubes (MWCNT) carbon aerogel (m-CPMCA) is reported using a simple freeze-drying followed by a carbonisation process, and direct immobilisation of Fe3O4 nanoparticle on the surface of aerogels. The obtained target aerogel has the characteristics of low density (0.098 g/cm3), high porosity (>90%) and 3D interpenetrating porous structures. Furthermore, m-CPMCA has a surprising compressive strength (about 0.35 MPa) which is obviously higher than many other cellulose-based carbon aerogels. After Carbonization, m-CPMCA exhibits superhydrophobicity, selective absorption for organic solvents and fire-resistance. The m-CPMCA also exhibited a magnetic response and can absorb oil on the water surface and can be actuated by a small magnet. More importantly, the m-CPMCA could be recycled many times by combustion, which showed economic significance. To sum up, the authors believe that m-CPMCA will become a very potential adsorbent for dealing with the increasingly serious problem of organic pollution.


Assuntos
Celulose/química , Géis/síntese química , Nanopartículas de Magnetita/química , Microtecnologia/métodos , Nanotubos de Carbono/química , Força Compressiva , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Fenômenos Magnéticos , Fenômenos Mecânicos , Nanofibras/química , Porosidade , Solventes , Estresse Mecânico , Água
13.
World Neurosurg ; 131: 197-199, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31299312

RESUMO

BACKGROUND: Superior oblique myokymia (SOM) is a rare disorder characterized by episodic microtremor of the eyeball. in patients with SOM, intermittent contraction of the superior oblique muscle causes irregular and rotatory eye movement, causing oscillopsia and diplopia. Microvascular decompression (MVD) of the trochlear nerve is potentially a definitive treatment method for SOM; however, owing to its rarity, this disorder is not well-known to neurosurgeons, and thus the optimal surgical approach has not yet been determined. CASE DESCRIPTION: A 77-year-old woman with left SOM had experienced oscillopsia for 2 years. MVD was performed via a left lateral superior cerebellar approach with the patient in the park-bench position. Her symptom resolved immediately after the surgery. CONCLUSIONS: We believe that MVD via a left lateral superior cerebellar approach can be safely performed to SOM in elderly patients like our patient. Therefore, MVD should be considered as the definitive treatment method for more patients with SOM.


Assuntos
Mioquimia/cirurgia , Transtornos da Motilidade Ocular/cirurgia , Idoso , Descompressão Cirúrgica/métodos , Feminino , Humanos , Microtecnologia/métodos , Músculos Oculomotores , Procedimentos Cirúrgicos Vasculares/métodos
14.
J Mater Sci Mater Med ; 30(8): 88, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31325082

RESUMO

Calcium phosphate (CaP)-containing materials, such as hydroxyapatite and brushite, are well studied bone grafting materials owing to their similar chemical compositions to the mineral phase of natural bone and kidney calculi. In recent studies, magnesium phosphate (MgP)-containing compounds, such as newberyite and struvite, have shown promise as alternatives to CaP. However, the different ways in degradation and release of Mg2+ and Ca2+ ions in vitro may affect the biocompatibility of CaP and MgP-containing compounds. In the present paper, newberyite, struvite, and brushite 3D porous structures were constructed by 3D-plotting combining with a two-step cementation process, using magnesium oxide (MgO) as a starting material. Briefly, 3D porous green bodies fabricated by 3D-plotting were soaked in (NH4)2HPO4 solution to form semi-manufactured 3D porous structures. These structures were then soaked in different phosphate solutions to translate the structures into newberyite, struvite, and brushite porous scaffolds. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS) were used to characterize the phases, morphologies, and compositions of the 3D porous scaffolds. The porosity, compressive strength, in vitro degradation and cytotoxicity on MC3T3-E1 osteoblast cells were assessed as well. The results showed that extracts obtained from immersing scaffolds in alpha-modified essential media induced minimal cytotoxicity and the cells could be attached merely onto newberyite and brushite scaffolds. Newberyite and brushite scaffolds produced through our 3D-plotting and two-step cementation process showed the sustained in vitro degradation and excellent biocompatibility, which could be used as scaffolds for the bone tissue engineering.


Assuntos
Materiais Biocompatíveis/síntese química , Fosfatos de Cálcio/química , Compostos de Magnésio/química , Óxido de Magnésio/farmacologia , Microtecnologia/métodos , Fosfatos/química , Estruvita/química , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Cimentos para Ossos/síntese química , Cimentos para Ossos/química , Células Cultivadas , Precipitação Química/efeitos dos fármacos , Força Compressiva , Óxido de Magnésio/química , Teste de Materiais , Camundongos , Conformação Molecular , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Polimerização/efeitos dos fármacos , Porosidade , Pós/síntese química , Pós/química , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
15.
Mater Sci Eng C Mater Biol Appl ; 103: 109785, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349447

RESUMO

Melt-electrospinning is a cost-effective and flexible process to fabricate micro-scaled polymeric fibers. Melt-electrospun microfiber structures have been receiving considerable attention from various fields due to their numerous advantages. However, the application of melt-electrospinning is limited by various factors, such as the sagging behavior and unstable whipping motion of microfibers. Here, we presented an experimental approach called beam bridge test to identify the sagging behavior of melt-electrospun microfibers for preparing 3D lattice structures with controllable architecture and well-defined pores in transverse direction. Consequently, the sagging behavior of melt-electrospun microfibers could be identified in a systematic manner. Moreover, the melt-electrospun 3D microfiber lattice structures with various grid sizes had sagging, which agreed well with the beam bridge test results. In addition, fibroblast cells (NIH-3T3) were cultured on the fabricated 3D microfiber lattice structures with various grid sizes. Cell culture results indicated that the cell growth was considerably influenced by microfiber sagging and the grid size of lattice structures. Also it was shown that the cell population for location could be controlled.


Assuntos
Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Microtecnologia/métodos , Células NIH 3T3 , Poliésteres/química , Engenharia Tecidual
16.
Biosensors (Basel) ; 9(3)2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31349554

RESUMO

A gold-coated array of flow-through inverse pyramids applicable as substrate for entrapment and immobilization of micro-objects and for surface enhanced Raman spectroscopic measurements was fabricated using bulk micromachining techniques from silicon. Surface morphology, optical reflectance, immobilization properties, and surface enhanced Raman amplification of the array were modelled and characterized. It was found that the special perforated periodic 3D structure can be used for parallel particle and cell trapping and highly sensitive molecular analysis of the immobilized objects.


Assuntos
Técnicas Biossensoriais/instrumentação , Análise Espectral Raman/instrumentação , Ouro/química , Nanopartículas Metálicas/química , Microtecnologia/métodos , Tamanho da Partícula , Silício , Análise Espectral Raman/métodos , Propriedades de Superfície
17.
Biofabrication ; 11(4): 045010, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31220812

RESUMO

Bacterial nanocellulose (BNC) has proven to be an effective hydrogel-like material for different tissue engineering applications due to its biocompatibility and good mechanical properties. However, as for all biomaterials, in vitro biosynthesis of large tissue constructs remains challenging due to insufficient oxygen and nutrient transport in engineered scaffold-cell matrices. In this study we designed, biofabricated and evaluated bacterial nanocellulose scaffolds with a complex vascular mimetic lumen structure. As a first step a method for creating straight channeled structures within a bacterial nanocellulose scaffold was developed and evaluated by culturing of Human Umbilical Vein Endothelial Cells (HUVECs). In a second step, more complex structures within the scaffolds were produced utilizing a 3D printer. A print mimicking a vascular tree acted as a sacrificial template to produce a network within the nanoporous bacterial nanocellulose scaffolds that could be lined with endothelial cells. In a last step, a method to produce large constructs with interconnected macro porosity and vascular like lumen structure was developed. In this process patient data from x-ray computed tomography scans was used to create a mold for casting a full-sized kidney construct. By showing that the 3D printing technology can be combined with BNC biosynthesis we hope to widen the opportunities of 3D printing, while also enabling the production of BNC scaffolds constructs with tailored vascular architectures and properties.


Assuntos
Vasos Sanguíneos/anatomia & histologia , Celulose/química , Microtecnologia/métodos , Nanopartículas/química , Tecidos Suporte/química , Celulose/ultraestrutura , Células Endoteliais da Veia Umbilical Humana , Humanos , Nanopartículas/ultraestrutura
18.
Biofabrication ; 11(3): 032005, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31215521

RESUMO

Biofabrication techniques have enabled the formation of complex models of many biological tissues. We present a framework to contextualize biofabrication techniques within a disease modeling application. Fibrosis is a progressive disease interfering with tissue structure and function, which stems from an aberrant wound healing response. Epithelial injury and clot formation lead to fibroblast invasion and activation, followed by contraction and remodeling of the extracellular matrix. These stages have healthy wound healing variants in addition to the pathogenic analogs that are seen in fibrosis. This review evaluates biofabrication of a variety of phenotypic cell-based fibrosis assays. By recapitulating different contributors to fibrosis, these assays are able to evaluate biochemical pathways and therapeutic candidates for specific stages of fibrosis pathogenesis. Biofabrication of these culture models may enable phenotypic screening for improved understanding of fibrosis biology as well as improved screening of anti-fibrotic therapeutics.


Assuntos
Bioensaio , Microtecnologia/métodos , Fibrose Pulmonar/patologia , Animais , Fibroblastos/patologia , Humanos , Modelos Biológicos , Fenótipo
19.
Biofabrication ; 11(3): 035025, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31096204

RESUMO

Recently, stromal cell spheroids have been actively studied for use in tissue regeneration. In this study, we report a method for the fabrication of size-controllable stromal cell spheroids in different sizes from micro-scaled cell sheets (µCS) using thermosensitive hydrogels and investigated their effects on stromal cell function. Mesenchymal stromal cells isolated from different tissues such as human turbinate tissue, bone marrow, and adipose tissue were adhered selectively to each micro-pattern (squares with widths of 100 and 400 µm) on the surface of the hydrogel and formed µCS. The diameters of the spheroids were modulated by the size of the patterns (45 ± 5 and 129 ± 4 µm in diameter for the 100 and 400 µm micro-patterns, respectively) and the seeding density (129 ± 4, 149 ± 6, and 163 ± 6 µm for 5.0, 10.0, and 15.0 × 104 cells cm-2, respectively, on 400 µm micro-pattern). In addition, the spheroids were successfully fabricated regardless of stromal cell origin, and the diameter of the spheroids was also affected by cell spreading area on a cell culture dish. Stemness markers were highly expressed in the spheroids regardless of the spheroid size. Furthermore, an increase in E-cadherin and decrease in N-cadherin gene expression showed the stable formation of spheroids of different sizes. Gene expression levels of hypoxia inducible factors and secretion of vascular endothelial growth factor were increased (13.2 ± 1.4, 325 ± 83.4 and 534.3 ± 121.5 pg ng-1 DNA in a monolayer, and 100 and 400 µm micro-patterned spheroids, respectively) proportional to the diameters of the spheroids. The size of spheroids were maintained even after injection, cryopreservation and 7 d of suspension culture with high viability (∼90%). In conclusion, this novel technique to fabricate spheroids with controlled size could be widely applied in various applications that require a controlled size in regenerative medicine.


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Mesenquimais/citologia , Microtecnologia/métodos , Esferoides Celulares/citologia , Indutores da Angiogênese/metabolismo , Adesão Celular/efeitos dos fármacos , Contagem de Células , Tamanho Celular , Criopreservação , Dimetilpolisiloxanos/química , Humanos , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Células Estromais/citologia , Células Estromais/efeitos dos fármacos
20.
Biofabrication ; 11(3): 032004, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31042682

RESUMO

Skeletal muscle is a tissue with a complex and hierarchical architecture that influences its functional properties. In order to exert its contractile function, muscle tissue is connected to neural, vascular and connective compartments, comprising finely structured interfaces which are orchestrated by multiple signalling pathways. Pathological conditions such as dystrophies and trauma, or physiological situations such as exercise and aging, modify the architectural organization of these structures, hence affecting muscle functionality. To overcome current limitations of in vivo and standard in vitro models, microfluidics and biofabrication techniques have been applied to better reproduce the microarchitecture and physicochemical environment of human skeletal muscle tissue. In the present review, we aim to critically discuss the role of those techniques, taken individually or in combination, in the generation of models that mimic the complex interfaces between muscle tissue and neural/vascular/tendon compartments. The exploitation of either microfluidics or biofabrication to model different muscle interfaces has led to the development of constructs with an improved spatial organization, thus presenting a better functionality as compared to standard models. However, the achievement of models replicating muscle-tissue interfaces with adequate architecture, presence of fundamental proteins and recapitulation of signalling pathways is still far from being achieved. Increased integration between microfluidics and biofabrication, providing the possibility to pattern cells in predetermined structures with higher resolution, will help to reproduce the hierarchical and heterogeneous structure of skeletal muscle interfaces. Such strategies will further improve the functionality of these techniques, providing a key contribution towards the study of skeletal muscle functions in physiology and pathology.


Assuntos
Microtecnologia/métodos , Músculo Esquelético/fisiologia , Engenharia Tecidual/métodos , Animais , Humanos , Modelos Biológicos , Músculo Esquelético/irrigação sanguínea , Tendões/fisiologia
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