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1.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35074913

RESUMEN

The exceptional elastic resilience of some protein materials underlies essential biomechanical functions with broad interest in biomedical fields. However, molecular design of elastic resilience is restricted to amino acid sequences of a handful of naturally occurring resilient proteins such as resilin and elastin. Here, we exploit non-resilin/elastin sequences that adopt kinetically stabilized, random coil-dominated conformations to achieve near-perfect resilience comparable with that of resilin and elastin. We also show a direct correlation between resilience and Raman-characterized protein conformations. Furthermore, we demonstrate that metastable conformation of proteins enables the construction of mechanically graded protein materials that exhibit spatially controlled conformations and resilience. These results offer insights into molecular mechanisms of protein elastomers and outline a general conformation-driven strategy for developing resilient and functional protein materials.


Asunto(s)
Modelos Moleculares , Conformación Proteica , Proteínas/química , Secuencia de Aminoácidos , Fibroínas/química , Análisis Espectral , Relación Estructura-Actividad
2.
Small ; 19(50): e2205078, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36587991

RESUMEN

Three-dimensional (3D) bioprinting is driving significant innovations in biomedicine over recent years. Under certain scenarios such as in intraoperative bioprinting, the bioinks used should exhibit not only cyto/biocompatibility but also adhesiveness in wet conditions. Herein, an adhesive bioink composed of gelatin methacryloyl, gelatin, methacrylated hyaluronic acid, and skin secretion of Andrias davidianus is designed. The bioink exhibits favorable cohesion to allow faithful extrusion bioprinting in wet conditions, while simultaneously showing good adhesion to a variety of surfaces of different chemical properties, possibly achieved through the diverse bonds presented in the bioink formulation. As such, this bioink is able to fabricate sophisticated planar and volumetric constructs using extrusion bioprinting, where the dexterity is further enhanced using ergonomic handheld bioprinters to realize in situ bioprinting. In vitro experiments reveal that cells maintain high viability; further in vivo studies demonstrate good integration and immediate injury sealing. The characteristics of the bioink indicate its potential widespread utility in extrusion bioprinting and will likely broaden the applications of bioprinting toward situations such as in situ dressing and minimally invasive tissue regeneration.


Asunto(s)
Bioimpresión , Andamios del Tejido , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Adhesivos , Gelatina/química , Piel , Cicatrización de Heridas , Impresión Tridimensional , Hidrogeles/química , Bioimpresión/métodos
3.
Bioorg Chem ; 138: 106623, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37295240

RESUMEN

Fangchinoline (Fan) are extracted from the traditional Chinese medicine Stephania tetrandra S., which is a bis-benzyl isoquinoline alkaloids with anti-tumor activity. Therefore, 25 novel Fan derivatives have been synthesized and evaluated for their anti-cancer activity. In CCK-8 assay, these fangchinoline derivatives displayed higher proliferation inhibitory activity on six tumor cell lines than the parental compound. Compared to the parent Fan, compound 2h presented the anticancer activity against most cancer cells, especially A549 cells, with an IC50 value of 0.26 µM, which was 36.38-fold, and 10.61-fold more active than Fan and HCPT, respectively. Encouragingly, compound 2h showed low biotoxicity to the human normal epithelial cell BEAS-2b with an IC50 value of 27.05 µM. The results indicated compound 2h remarkably inhibited the cell migration by decreasing MMP-2 and MMP-9 expression and inhibited the proliferation of A549 cells by arresting the G2/M cell cycle. Meanwhile, compound 2h could also induce A549 cell apoptosis by promoting endogenous pathways of mitochondrial regulation. In nude mice presented that the growth of tumor tissues was markedly inhibited by the consumption of compound 2h in a dose-dependent manner, and it was found that compound 2h could inhibit the mTOR/PI3K/AKT pathway in vivo. In docking analysis, high affinity interaction between 2h and PI3K was responsible for drastic kinase inhibition by the compound. To conclude, this derivative compound may be useful as a potent anti-cancer agent for treatment of NSCLC.


Asunto(s)
Antineoplásicos , Bencilisoquinolinas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Ratones , Animales , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Ratones Desnudos , Neoplasias Pulmonares/metabolismo , Proliferación Celular , Bencilisoquinolinas/farmacología , Bencilisoquinolinas/uso terapéutico , Línea Celular Tumoral , Apoptosis , Proteínas Proto-Oncogénicas c-akt/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico
4.
Proc Natl Acad Sci U S A ; 117(25): 14602-14608, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32522869

RESUMEN

Bioinspired actuators with stimuli-responsive and deformable properties are being pursued in fields such as artificial tissues, medical devices and diagnostics, and intelligent biosensors. These applications require that actuator systems have biocompatibility, controlled deformability, biodegradability, mechanical durability, and stable reversibility. Herein, we report a bionic actuator system consisting of stimuli-responsive genetically engineered silk-elastin-like protein (SELP) hydrogels and wood-derived cellulose nanofibers (CNFs), which respond to temperature and ionic strength underwater by ecofriendly methods. Programmed site-selective actuation can be predicted and folded into three-dimensional (3D) origami-like shapes. The reversible deformation performance of the SELP/CNF actuators was quantified, and complex spatial transformations of multilayer actuators were demonstrated, including a biomimetic flower design with selective petal movements. Such actuators consisting entirely of biocompatible and biodegradable materials will offer an option toward constructing stimuli-responsive systems for in vivo biomedicine soft robotics and bionic research.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biomiméticos/química , Biónica/métodos , Celulosa/química , Elastina/química , Elastina/genética , Hidrogeles/química , Conformación Molecular , Nanofibras/química , Ingeniería de Proteínas , Robótica/métodos , Seda/química , Seda/genética
5.
Bioorg Chem ; 126: 105916, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35687986

RESUMEN

Hyperuricemia is a common metabolic disease with a series of complications. Nuciferine, a typical aporphine alkaloid natural compound extracted from the leaves of Nelumbo nucifera Gaertn., was confirmed to have an antihyperuricemia effect. In the present study, 30 novel nuciferine derivatives were designed and synthesized. The effects of all derivatives on the regulation of URAT1 were studied in a uric acid-induced HK-2 cell model with benzbromarone as a positive control. The results indicated that Compound 1j showed the optimal URAT1 inhibitory activity through repressing PI3K/Akt pathway in HK-2 cells and the inhibitory effect was similar to that of benzbromarone. In addition, in vivo experiments demonstrated that Compound 1j could reduce uric acid levels and ameliorate kidney damage in hyperuricemic mice. On the one hand, Compound 1j could inhibit the expression of URAT1 and GLUT9 to increase the uric acid excretion index. On the other hand, Compound 1j could regulate the TLR4/IκBα/NF-κB signaling pathway to reduce the levels of inflammatory cytokines, thereby alleviating kidney damage. Meanwhile, a molecular docking assay revealed the potential molecular binding power (-9.79 kcal/mol) between Compound 1j and URAT1, which was more tightly bound than the lead compound nuciferine (-7.44 kcal/mol). Based on these results, Compound 1j may be a future drug for the development of new potential antihyperuricemia and nephroprotective drug candidates.


Asunto(s)
Aporfinas , Hiperuricemia , Transportadores de Anión Orgánico , Animales , Aporfinas/farmacología , Benzbromarona/efectos adversos , Hiperuricemia/tratamiento farmacológico , Ratones , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas/metabolismo , Ácido Úrico
6.
Bioorg Chem ; 119: 105483, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34906860

RESUMEN

The nuclear receptor retinoic acid receptor-related orphan receptor γ (RORγ, NR1F3, or RORc) exists in two isoforms, with one isoform (RORγ or RORc1) widely expressed in a variety of tissues, and the expression of the second isoform (RORγt or RORc2) restricted to the thymus and cells of the immune system. RORγt is a key regulator of the development and functions of T-helper 17 (Th17) cells. Clinical proof-of-concept (PoC) with small molecule inverse agonists of RORγt has been achieved with VTP-43742 (Phase II) for the treatment of psoriasis, and pre-clinical PoC for this mechanism has also been established for the treatment of autoimmune diseases. A series of aryl sulfonyl derivatives as novel RORγt inverse agonists were designed and synthesized based on VTP-43742. We conducted structural modifications that improved the activity profile. In pharmacodynamic (PD) studies, oral administration of compound b12 showed robust and dose-dependent inhibition of IL-6 and IL-17A cytokine expression. The ability of compound b12 to reduce the levels of IL-6 and IL-17A in vivo after oral dosing in mice, and a corresponding reduction in skin inflammation further supports the potential of small molecule RORγt modulation as a therapeutic target for the treatment of inflammatory diseases.


Asunto(s)
Descubrimiento de Drogas , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/agonistas , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Estructura Molecular , Relación Estructura-Actividad
7.
Molecules ; 27(7)2022 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-35408547

RESUMEN

Silk fibroin, regenerated from Bombyx mori, has shown considerable promise as a printable, aqueous-based ink using a bioinspired salt-bath system in our previous work. Here, we further developed and characterized silk fibroin inks that exhibit concentration-dependent fluorescence spectra at the molecular level. These insights supported extrusion-based 3D printing using concentrated silk fibroin solutions as printing inks. 3D monolithic proteinaceous structures with high aspect ratios were successfully printed using these approaches, including cantilevers only supported at one end. This work provides further insight and broadens the utility of 3D printing with silk fibroin inks for the microfabrication of proteinaceous structures.


Asunto(s)
Bombyx , Fibroínas , Animales , Fibroínas/química , Tinta , Impresión Tridimensional , Seda/química , Agua
8.
Angew Chem Int Ed Engl ; 61(33): e202207066, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35674195

RESUMEN

In the electronics industry, the efficient recovery and capture of sulfur hexafluoride (SF6 ) from SF6 /N2 mixtures is of great importance. Herein, three metal-organic frameworks with fine-tuning pore structures, Cu(peba)2 , Ni(pba)2 , and Ni(ina)2 , were designed for SF6 capture. Among them, Ni(ina)2 has perfect pore sizes (6 Å) that are comparable to the kinetic diameter of sulfur hexafluoride (5.2 Å), affording the benchmark binding affinity for SF6 gas. Ni(ina)2 exhibits the highest SF6 /N2 selectivity (375.1 at 298 K and 1 bar) and ultra-high SF6 uptake capacity (53.5 cm3 g-1 at 298 K and 0.1 bar) at ambient conditions. The remarkable separation performance of Ni(ina)2 was verified by dynamic breakthrough experiments. Theoretical calculations and the SF6 -loaded single-crystal structure provided critical insight into the adsorption/separation mechanism. This porous coordination network has the potential to be used in industrial applications.

9.
Prog Polym Sci ; 1152021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33776158

RESUMEN

Three-dimensional (3D) printing is a transformative manufacturing strategy, allowing rapid prototyping, customization, and flexible manipulation of structure-property relationships. Proteins are particularly appealing to formulate inks for 3D printing as they serve as essential structural components of living systems, provide a support presence in and around cells and for tissue functions, and also provide the basis for many essential ex vivo secreted structures in nature. Protein-based inks are beneficial in vivo due to their mechanics, chemical and physical match to the specific tissue, and full degradability, while also to promoting implant-host integration and serving as an interface between technology and biology. Exploiting the biological, chemical, and physical features of protein-based inks can provide key opportunities to meet the needs of tissue engineering and regenerative medicine. Despite these benefits, protein-based inks impose nontrivial challenges to 3D printing such as concentration and rheological features and reconstitution of the structural hierarchy observed in nature that is a source of the robust mechanics and functions of these materials. This review introduces photo-crosslinking mechanisms and rheological principles that underpins a variety of 3D printing techniques. The review also highlights recent advances in the design, development, and biomedical utility of monolithic and composite inks from a range of proteins, including collagen, silk, fibrinogen, and others. One particular focus throughout the review is to introduce unique material characteristics of proteins, including amino acid sequences, molecular assembly, and secondary conformations, which are useful for designing printing inks and for controlling the printed structures. Future perspectives of 3D printing with protein-based inks are also provided to support the promising spectrum of biomedical research accessible to these materials.

10.
Nat Mater ; 19(1): 102-108, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31844276

RESUMEN

Early insights into the unique structure and properties of native silk suggested that ß-sheet nanocrystallites in silk would degrade prior to melting when subjected to thermal processing. Since then, canonical approaches for fabricating silk-based materials typically involve solution-derived processing methods, which have inherent limitations with respect to silk protein solubility and stability in solution, and time and cost efficiency. Here we report a thermal processing method for the direct solid-state moulding of regenerated silk into bulk 'parts' or devices with tunable mechanical properties. At elevated temperature and pressure, regenerated amorphous silk nanomaterials with ultralow ß-sheet content undergo thermal fusion via molecular rearrangement and self-assembly assisted by bound water to form a robust bulk material that retains biocompatibility, degradability and machinability. This technique reverses presumptions about the limitations of direct thermal processing of silk into a wide range of new material formats and composite materials with tailored properties and functionalities.


Asunto(s)
Materiales Biocompatibles/química , Nanoestructuras/química , Seda/química , Animales , Bombyx , Fuerza Compresiva , Femenino , Fibroínas/química , Calor , Espectroscopía de Resonancia Magnética , Estructura Secundaria de Proteína , Ratas , Ratas Sprague-Dawley , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Estrés Mecánico , Resistencia a la Tracción , Agua/química , Microtomografía por Rayos X
11.
Biomacromolecules ; 22(2): 773-787, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33405916

RESUMEN

The oxidation of tyrosine residues of silk fibroin involves the generation of dityrosine and 3,4-dihydroxyphenylalanine (DOPA). However, it remains a challenge to selectively control the reaction pathway to produce dityrosine or DOPA in a selective fashion. Here, silk hydrogels with controllable formation of not only dityrosine and DOPA but also DOPA-Fe3+ complexes within the cross-linked networks were developed. The use of chitosan particles in the Fenton reaction allowed the interaction of Fe3+ ions with silk fibroin to be limited through the adsorption of Fe3+ ions onto chitosan particles by manipulating contact time between the reaction medium and chitosan particles. This led to significant suppression of the premature formation of ß-sheet structures that cause steric hindrance to the collisions between tyrosyl radicals and thus enabled higher selectivity toward the formation of dityrosine than DOPA. Remarkably, the addition of ethylenediaminetetraacetic acid (EDTA) to the chitosan particle-assisted Fenton reactions resulted in hydrogels that significantly favored the formation of DOPA over dityrosine due to the increase in the hydroxylation of phenol in the presence of EDTA. Despite the existence of Fe3+-EDTA complexes, Raman spectra indicated the DOPA-Fe3+ complexation in the hydrogels. Mechanistically, the hydrogel networks with small-sized and uniformly distributed ß-sheet structures as well as the abundance of DOPA appear to make non-EDTA-chelated Fe3+ ions more accessible to complexation with DOPA. These findings have important implications for understanding the oxidation of tyrosine residues of silk fibroin by metal-catalyzed oxidation systems with potential benefits for future studies on silk protein-based hydrogels capable of generating intrinsic adhesive features as well as for exploring dual-cross-linked silk hydrogels constructed by chemical cross-linking and metal-coordinate complexation.


Asunto(s)
Quitosano , Fibroínas , Dihidroxifenilalanina , Hidrogeles , Seda , Tirosina/análogos & derivados
12.
Biomacromolecules ; 22(2): 788-799, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33337131

RESUMEN

Low-molecular weight (LMW) silk was utilized as a LMW silk plasticizer for regenerated silk, generating weak physical crosslinks between high-molecular weight (HMW) silk chains in the amorphous regions of a mixed solution of HMW/LMW silk. The plasticization effect of LMW silk was investigated using mechanical testing, Raman spectroscopy, and wide-angle X-ray scattering (WAXS). Small amounts (10%) of LMW silk resulted in a 19.4% enhancement in fiber extensibility and 37.8% increase in toughness. The addition of the LMW silk facilitated the movement of HMW silk chains during drawing, resulting in an increase in molecular chain orientation when compared with silk spun from 100% HMW silk solution. The best regenerated silk fibers produced in this work had an orientation factor of 0.94 and crystallinity of 47.82%, close to the values of natural degummedBombyx mori silk fiber. The approach and mechanism elucidated here can facilitate artificial silk systems with enhanced properties.


Asunto(s)
Bombyx , Fibroínas , Animales , Peso Molecular , Seda , Espectrometría Raman
13.
Bioorg Chem ; 109: 104694, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33601141

RESUMEN

Cancer treatment is one of the major public health issues in the world. Tetrandrine (Tet) and fangchinoline (d-Tet) are two bis-benzyl isoquinoline alkaloids extracted from Stephania tetrandra S. Moore, and their antitumor activities have been confirmed. However, the effective dose of Tet and d-Tet were much higher than that of the positive control and failed to meet clinical standards. Therefore, in this study, as a continuation of our previous work to study and develop high-efficiency and low-toxic anti-tumor lead compounds, twenty new Tet and d-Tet derivatives were designed, synthesized and evaluated as antitumor agents against six cancer cell lines (H460, H520, HeLa, HepG-2, MCF-7, SW480 cell lines) and BEAS-2B normal cells by CCK-8 analysis. Ten derivatives showed better cytotoxic effects than the parent fangchinoline, of which 4g showed the strongest cell growth inhibitory activity with an IC50 value of 0.59 µM against A549 cells. Subsequently, the antitumor mechanism of 4g was studied by flow cytometry, Hoechst 33258, JC-1 staining, cell scratch, transwell migration, and Western blotting assays. These results showed that compound 4g could inhibit A549 cell proliferation by arresting the G2/M cell cycle and inhibiting cell migration and invasion by reducing MMP-2 and MMP-9 expression. Meanwhile, 4g could induce apoptosis of A549 cells through the intrinsic pathway regulated by mitochondria. In addition, compound 4g inhibited the phosphorylation of PI3K, Akt and mTOR, suggesting a correlation between blocking the PI3K/Akt/mTOR pathway and the above antitumor activities. These results suggest that compound 4g may be a future drug for the development of new potential drug candidates against lung cancer.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Bencilisoquinolinas/química , Diseño de Fármacos , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Humanos , Estructura Molecular
14.
Gut ; 69(3): 513-522, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31900289

RESUMEN

OBJECTIVE: Pre-eclampsia (PE) is one of the malignant metabolic diseases that complicate pregnancy. Gut dysbiosis has been identified for causing metabolic diseases, but the role of gut microbiome in the pathogenesis of PE remains unknown. DESIGN: We performed a case-control study to compare the faecal microbiome of PE and normotensive pregnant women by 16S ribosomal RNA (rRNA) sequencing. To address the causative relationship between gut dysbiosis and PE, we used faecal microbiota transplantation (FMT) in an antibiotic-treated mouse model. Finally, we determined the microbiome translocation and immune responses in human and mouse placental samples by 16S rRNA sequencing, quantitative PCR and in situ hybridisation. RESULTS: Patients with PE showed reduced bacterial diversity with obvious dysbiosis. Opportunistic pathogens, particularly Fusobacterium and Veillonella, were enriched, whereas beneficial bacteria, including Faecalibacterium and Akkermansia, were markedly depleted in the PE group. The abundances of these discriminative bacteria were correlated with blood pressure (BP), proteinuria, aminotransferase and creatinine levels. On successful colonisation, the gut microbiome from patients with PE triggered a dramatic, increased pregestational BP of recipient mice, which further increased after gestation. In addition, the PE-transplanted group showed increased proteinuria, embryonic resorption and lower fetal and placental weights. Their T regulatory/helper-17 balance in the small intestine and spleen was disturbed with more severe intestinal leakage. In the placenta of both patients with PE and PE-FMT mice, the total bacteria, Fusobacterium, and inflammatory cytokine levels were significantly increased. CONCLUSIONS: This study suggests that the gut microbiome of patients with PE is dysbiotic and contributes to disease pathogenesis.


Asunto(s)
Traslocación Bacteriana , Disbiosis/complicaciones , Microbioma Gastrointestinal , Placenta/inmunología , Placenta/microbiología , Preeclampsia/microbiología , Animales , Presión Sanguínea , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Quimiocinas/genética , Creatinina/sangre , Citocinas/genética , Modelos Animales de Enfermedad , Disbiosis/fisiopatología , Faecalibacterium , Heces/microbiología , Femenino , Reabsorción del Feto/microbiología , Fusobacterias , Humanos , Intestino Delgado/inmunología , Ratones , Placenta/metabolismo , Preeclampsia/fisiopatología , Embarazo , Proteinuria/orina , ARN Mensajero/metabolismo , Linfocitos T Reguladores , Células Th17 , Veillonella
15.
Bioorg Chem ; 94: 103431, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31759658

RESUMEN

The isolation and modification of natural products play an important role in the synthesis of anti-tumor drugs for the treatment of cancer. The present study was designed to evaluate the effects of fangchinoline derivatives against cancer cells. In vitro cytotoxicity of all derivatives against five cancer cell lines (A549, Hela, HepG-2, MCF-7 and MDA-MB-231 cell lines) and HL-7702 normal cells was assessed using the CCK-8 assay, and the results showed that most of the synthesized compounds displayed better cytotoxic effects on all the tested cells compared to that of the parent fangchinoline. In particular, compound 3i had the strongest inhibitory effect on cell proliferation, with an IC50 value of 0.61 µM against A549 cells. Compared with fangchinoline and HCPT (hydroxycamptothecine), the anti-proliferative activity of compound 3i was significantly increased. More interestingly, compound 3i had slight toxic side effects on normal cells, with an IC50 value of 27.53 µM. Moreover, the cell viability and cell cycle assays revealed that compound 3i inhibited A549 cell proliferation and arrested A549 cells at the G2/M-phase. The apoptosis-inducing effects of compound 3i and the associated molecular mechanisms were assessed using flow cytometry, cell staining, reactive oxygen species assays, RT-qPCR and Western blot analysis. These results suggested that compound 3i induces apoptosis through a mitochondria-mediated intrinsic pathway. This study revealed that compound 3i is a promising candidate for future development as an anti-tumor drug.


Asunto(s)
Antineoplásicos/farmacología , Bencilisoquinolinas/farmacología , Diseño de Fármacos , Células A549 , Antineoplásicos/síntesis química , Antineoplásicos/química , Bencilisoquinolinas/síntesis química , Bencilisoquinolinas/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Relación Estructura-Actividad
16.
Small ; 15(23): e1805510, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31033203

RESUMEN

Over the last decades, the fabrication of 3D tissues has become commonplace in tissue engineering and regenerative medicine. However, conventional 3D biofabrication techniques such as scaffolding, microengineering, and fiber and cell sheet engineering are limited in their capacity to fabricate complex tissue constructs with the required precision and controllability that is needed to replicate biologically relevant tissues. To this end, 3D bioprinting offers great versatility to fabricate biomimetic, volumetric tissues that are structurally and functionally relevant. It enables precise control of the composition, spatial distribution, and architecture of resulting constructs facilitating the recapitulation of the delicate shapes and structures of targeted organs and tissues. This Review systematically covers the history of bioprinting and the most recent advances in instrumentation and methods. It then focuses on the requirements for bioinks and cells to achieve optimal fabrication of biomimetic constructs. Next, emerging evolutions and future directions of bioprinting are discussed, such as freeform, high-resolution, multimaterial, and 4D bioprinting. Finally, the translational potential of bioprinting and bioprinted tissues of various categories are presented and the Review is concluded by exemplifying commercially available bioprinting platforms.


Asunto(s)
Bioimpresión/métodos , Impresión Tridimensional , Medicina Regenerativa/tendencias , Investigación Biomédica Traslacional , Biomimética/métodos , Biomimética/tendencias , Humanos , Medicina Regenerativa/métodos , Ingeniería de Tejidos/métodos , Investigación Biomédica Traslacional/métodos , Investigación Biomédica Traslacional/tendencias
17.
Adv Funct Mater ; 28(9)2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-30505261

RESUMEN

The production of structural and functional materials with enhanced mechanical properties through the integration of soft and hard components is a common approach to Nature's materials design. However, directly mimicking these optimized design routes in the lab for practical applications remains challenging. For example, graphene and silk are two materials with complementary mechanical properties that feature ultrahigh stiffness and toughness, respectively. Yet no simple and controllable approach has been developed to homogeneously integrate these two components into functional composites, mainly due to the hydrophobicity and chemical inertness of the graphene. In this study, well-dispersed and highly stable graphene/silk fibroin (SF) suspension systems were developed, which are suitable for processing to fabricate polymorphic materials, such as films, fibers, and coatings. The obtained graphene/SF nanocomposites maintain the electronic advantages of graphene, and they also allow tailorable mechanical performance to form including ultrahigh stretchable (with a strain to failure to 611±85%), or high strength (339 MPa) and high stiffness (7.4 GPa) material systems. More remarkably, the electrical resistances of these graphene/SF materials are sensitive to material deformation, body movement, as well as humidity and chemical environmental changes. These unique features promise their utility as wearable sensors, smart textiles, intelligent skins, and human-machine interfaces.

18.
BMC Plant Biol ; 17(1): 236, 2017 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-29216819

RESUMEN

BACKGROUND: Ground-level ozone (O3) is one of the major air pollutants, which cause oxidative injury to plants. The physiological and biochemical mechanisms underlying the responses of plants to O3 stress have been well investigated. However, there are limited reports about the molecular basis of plant responses to O3. In this study, a comparative transcriptomic analysis of Pak Choi (Brassica campestris ssp. chinensis) exposed to different O3 concentrations was conducted for the first time. RESULTS: Seedlings of Pak Choi with five leaves were exposed to non-filtered air (NF, 31 ppb) or elevated O3 (E-O3, 252 ppb) for 2 days (8 h per day, from 9:00-17:00). Compared with plants in the NF, a total of 675 differentially expressed genes (DEGs) were identified in plants under E-O3, including 219 DEGs with decreased expressions and 456 DEGs with increased expressions. Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that O3 stress invoked multiple cellular defense pathways to mitigate the impaired cellular integrity and metabolism, including 'glutathione metabolism', 'phenylpropanoid biosynthesis', 'sulfur metabolism', 'glucosinolate biosynthesis', 'cutin, suberine and wax biosynthesis' and others. Transcription factors potentially involved in this cellular regulation were also found, such as AP2-ERF, WRKY, JAZ, MYB etc. Based on the RNA-Seq data and previous studies, a working model was proposed integrating O3 caused reactive oxygen burst, oxidation-reduction regulation, jasmonic acid and downstream functional genes for the regulation of cellular homeostasis after acute O3 stress. CONCLUSION: The present results provide a valuable insight into the molecular responses of Pak Choi to acute O3 stress and the specific DEGs revealed in this study could be used for further functional identification of key allelic genes determining the O3 sensitivity of Pak Choi.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Brassica/genética , Genes de Plantas , Ozono/toxicidad , Estrés Fisiológico/genética , Transcriptoma/fisiología , Brassica/efectos de los fármacos , Brassica/metabolismo , Perfilación de la Expresión Génica , Plantones/efectos de los fármacos , Plantones/metabolismo , Estrés Fisiológico/efectos de los fármacos
19.
Clin Lab ; 62(1-2): 227-34, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27012054

RESUMEN

BACKGROUND: Quantitative polymerase chain reaction (qPCR) analysis is a precise and effective method for the study of mRNA expression throughout the field of peripheral blood mononuclear cell (PBMC) research. However, the use of suitable reference genes for data normalization is critical to obtain meaningful and reproducible results. The present study aimed to identify the greatest reference genes for further research in PBMC of Chronic Hepatitis B (CHB) patients. METHODS: We assessed the expression stability of four commonly used reference genes (beta actin, beta-tubulin, 18S rRNA, GAPDH) in PBMC of CHB patients. Then we employed geNorm, BestKeeper, and Normfinder to evaluate the expression stability of these reference genes. RESULTS: All four genes displayed no significant differences between patient and control groups except beta actin and thus beta actin should not be used as a normalizing gene in a discussed experimental setup. GAPDH and beta-tubulin composed the best pair of reference genes for normalization purposes in future studies of gene expression in PBMC of CHB patients according to three algorithms. CONCLUSIONS: GAPDH and beta-tubulin were the best combination of two reference genes in this study for RT-qPCR analysis.


Asunto(s)
Perfilación de la Expresión Génica/normas , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Hepatitis B Crónica/genética , Leucocitos Mononucleares/química , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Tubulina (Proteína)/genética , Actinas/genética , Algoritmos , Calibración , Estudios de Casos y Controles , Perfilación de la Expresión Génica/métodos , Marcadores Genéticos , Hepatitis B Crónica/sangre , Hepatitis B Crónica/diagnóstico , Humanos , Leucocitos Mononucleares/virología , Valor Predictivo de las Pruebas , ARN Mensajero/sangre , ARN Ribosómico 16S/genética , Estándares de Referencia
20.
Clin Lab ; 62(12): 2313-2318, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28164560

RESUMEN

BACKGROUND: The primary aim of this study is to measure the JAK-STAT signaling in HBV infected peripheral blood mononuclear cells (PBMCs) stimulated by IFN-α and 3-TC and explore the influence of HBV to the JAKSTAT signaling pathways. METHODS: PBMCs were separated from healthy volunteers and patients who had not received any treatment with chronic hepatitis B. PBMCs were divided into the control group, IFN-α stimulation group, Lamivudine stimulation group, and combined treatment group. The expression of molecules of JAK-STAT signal transduction pathway (STAT1, STAT2, IRF9) and the antiviral protein (MxA) were detected by RT-qPCR and Western blot method. RESULTS: The majority of IFN-α inducible genes were expressed. The molecules of JAK-STAT signal transduction pathway (STAT1, STAT2, IRF9) and the antiviral protein (MxA) were highly expressed in IFN-α stimulation group and the combined treatment group. Compared to healthy controls, the expression levels of molecules (STAT1, IRF9) and the antiviral protein (MxA) are significantly lower in the control group, IFN-α stimulation group, and the combined treatment group of the CHB patients. CONCLUSIONS: IFN-α could activate JAK-STAT signaling transduction pathway in PBMCs of HBV-infected patients and HBV might process the activity to antagonize the antiviral activity in HBV infected PBMCs.


Asunto(s)
Antivirales/farmacología , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/farmacología , Lamivudine/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Estudios de Casos y Controles , Células Cultivadas , Quimioterapia Combinada , Hepatitis B Crónica/genética , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/metabolismo , Humanos , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/genética , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Quinasas Janus/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Proteínas de Resistencia a Mixovirus/genética , Proteínas de Resistencia a Mixovirus/metabolismo , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/genética , Factor de Transcripción STAT2/metabolismo , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba
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