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1.
Anal Chem ; 96(19): 7609-7617, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38687631

RESUMO

MicroRNAs (miRNAs) play vital roles in biological activities, but their in vivo imaging is still challenging due to the low abundance and the lack of efficient fluorescent tools. RNA aptamers with high affinity and low background emerge for bioimaging yet suffering from low brightness. We introduce a rational design based on target-mediated entropy-driven toehold exchange (EDTE) to induce the release of RNA aptamer and subsequently light up corresponding fluorophore, which achieves selective imaging of miRNAs with good stability in both living cells and tumor-bearing mouse. Through tailoring recognition unit of the EDTE probes, highly sensitive imaging of different miRNAs including miRNA-125b and miRNA-21 is achieved, confirming its universal bioimaging applications. In comparison with the reported "one-to-one" model, the EDTE strategy shows a remarkable 4.6-time improvement in signal/noise ratio for intracellular imaging of the same miRNA. Particularly, it realizes sensitive imaging of miRNA in vivo, providing a promising tool in investigating functions and interactions of disease-associated miRNAs.


Assuntos
Aptâmeros de Nucleotídeos , Entropia , Corantes Fluorescentes , MicroRNAs , MicroRNAs/análise , MicroRNAs/metabolismo , Aptâmeros de Nucleotídeos/química , Animais , Corantes Fluorescentes/química , Camundongos , Humanos , Imagem Óptica , Camundongos Nus
2.
Adv Healthc Mater ; 13(20): e2304591, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38528711

RESUMO

The emerging cell death modality of ferroptosis has garnered increasing attention for antitumor treatment but still suffers from low therapeutic efficacy. A metal-organic frameworks (MOFs)-based magnetic nanozyme (PZFH) comprising porphyrin-based Zr-MOF (PCN) on zinc ferrite (ZF) nanoparticles modified with hyaluronic acid, delivering excellent magnetophotonic response for efficient ferroptosis, is reported here. PZFH shows multienzyme-like cascade activity encompassing a photon-triggered oxidase-like catalysis to generate O2 -, which is converted to H2O2 by superoxide dismutase-like activity and subsequent ·OH by magneto-promoted peroxidase (POD) behavior. Newly formed Fe─N coordination and increased Fe2+/Fe3+ levels in the PZFH contribute to the enhanced POD activity, which is further enhanced by accelerated surface electron transfer when exposure to alternated magnetic field. Accumulation of lipid peroxides is eventually accomplished through the conversion of ·OH radicals and singlet oxygen (1O2) produced through laser irradiation. When combined with the depletion of inhibition of glutathione and glutathione peroxidase 4, PZFH exhibits significantly enhanced ferroptosis in tumor-bearing mice, offering insights into nanomedicine for ferroptosis and holding great promise in clinical antitumor therapies.


Assuntos
Ferroptose , Estruturas Metalorgânicas , Espécies Reativas de Oxigênio , Ferroptose/efeitos dos fármacos , Animais , Camundongos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Humanos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Porfirinas/química , Porfirinas/farmacologia , Compostos Férricos/química , Camundongos Endogâmicos BALB C , Ácido Hialurônico/química
3.
Adv Biol (Weinh) ; 8(4): e2300668, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38327153

RESUMO

DNA methyltransferase is significant in cellular activities and gene expression, and its aberrant expression is closely linked to various cancers during initiation and progression. Currently, there is a great demand for reliable and label-free techniques for DNA methyltransferase evaluation in tumor diagnosis and cancer therapy. Herein, a low-background fluorescent RNA aptamer-based sensing approach for label-free quantification of cytosine-guanine (CpG) dinucleotides methyltransferase (M.SssI) is reported. The fluorogenic light-up RNA aptamers-based strategy exhibits high selectivity via restriction endonuclease, padlock-based recognition, and RNA transcription. By combining rolling circle amplification (RCA), and RNA transcription with fluorescence response of RNA aptamers of Spinach-dye compound, the proposed platform exhibited efficiently ultrahigh sensitivity toward M.SssI. Eventually, the detection can be achieved in a linear range of 0.02-100 U mL-1 with a detection limit of 1.6 × 10-3 U mL-1. Owing to these superior features, the method is further applied in serum samples spiked M.SssI, which delivers a recovery ranging from 92.0 to 107.0% and a relative standard deviation <7.0%, providing a promising and practical tool for determining M.SssI in complex biological matrices.


Assuntos
Aptâmeros de Nucleotídeos , Aptâmeros de Nucleotídeos/genética , Metilases de Modificação do DNA , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA/metabolismo , RNA
4.
J Mater Chem B ; 12(6): 1404-1428, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38251275

RESUMO

Magnetic two-dimensional nanocomposites (M2D NCs) that synergistically combine magnetic nanomedicine and 2D nanomaterials have emerged in multimodal antitumor therapy, attracting great interest in materials science and biomedical engineering. This review provides a summary of the recent advances of M2D NCs and their multimodal antitumor applications. We first introduce the design and fabrication of M2D NCs, followed by discussing new types of M2D NCs that have been recently reported. Then, a detailed analysis and discussions about the different types of M2D NCs are presented based on the structural categories of 2D NMs, including 2D graphene, transition metal dichalcogenides (TMDs), transition metal carbides/nitrides/carbonitrides (MXenes), black phosphorus (BP), layered double hydroxides (LDHs), metal organic frameworks (MOFs), covalent organic frameworks (COFs) and other 2D nanomaterials. In particular, we focus on the synthesis strategies, magnetic or optical responsive performance, and the versatile antitumor applications, which include magnetic hyperthermia therapy (MHT), photothermal therapy (PTT), photodynamic therapy (PDT), drug delivery, immunotherapy and multimodal imaging. We conclude the review by proposing future developments with an emphasis on the mass production and biodegradation mechanism of the M2D NCs. This work is expected to provide a comprehensive overview to researchers and engineers who are interested in such a research field and promote the clinical translation of M2D NCs in practical applications.


Assuntos
Hipertermia Induzida , Nanocompostos , Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Nanocompostos/química , Fenômenos Magnéticos
5.
Gels ; 9(10)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37888377

RESUMO

Fractured-vuggy reservoirs are mainly composed of three types: underground rivers, vugs, and fractured-vuggy structures. Based on the similarity criterion, a 3D model can truly reflect the characteristics of the multi-scale space of a fractured-vuggy reservoir, and it can reflect fluid flow laws in the formation. Water flooding, gas flooding, and gel foam flooding were carried out in the model sequentially. Based on gas flooding, the enhanced recovery ratio of gel foam flooding in the underground river was approximately 12%. By changing the injection rate, the average recovery ratio of nitrogen flooding was 6.84% higher than that of other injection rates at 5 mL/min, and that of gel foam flooding was 1.88% higher than that of other injection rates at 5 mL/min. The experimental results showed that the gel foam induced four oil displacement mechanisms, which selectively plugged high-permeability channels, controlled the mobility ratio, reduced oil-water interfacial tension, and changed the wettability of rock surfaces. With different injection-production methods, gel foam flooding can spread across two underground river channels. Two cases of nitrogen flooding affected one underground river channel and two underground river channels. By adjusting the injection rate, it was found that after nitrogen flooding, there were mainly four types of residual oil, and gel foam flooding mainly yielded three types of remaining oil. This study verified the influencing factors of extracting residual oil from an underground river and provides theoretical support for the subsequent application of gel foam flooding in underground rivers.

6.
Biosens Bioelectron ; 235: 115389, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37216843

RESUMO

The yarn-based sweat-activated battery (SAB) is a promising energy source for textile electronics due to its excellent skin compatibility, great weavability, and stable electric output. However, its power density is too low to support real-time monitoring and wireless data transmission. Here, we developed a scalable, high-performance sweat-based yarn biosupercapacitor (SYBSC) with two symmetrically aligned electrodes made by wrapping hydrophilic cotton fibers on polypyrrole/poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate)-modified stainless steel yarns. Once activated with artificial sweat, the SYBSC could offer a high areal capacitance of 343.1 mF cm-2 at 0.5 mA cm-2. After 10,000 times of bending under continuous charge-discharge cycles and 25 cycles of machine washing, the device could retain the capacitance at rates of 68% and 73%, respectively. The SYBSCs were integrated with yarn-shaped SABs to produce hybrid self-charging power units. The hybrid units, pH sensing fibers, and a mini-analyzer were woven into a sweat-activated all-in-one sensing textile, in which the hybrid, self-charging units could power the analyzer for real-time data collection and wireless transmission. The all-in-one electronic textile could be successfully employed to real-time monitor the pH values of the volunteers' sweat during exercise. This work can promote the development of self-charging electronic textiles for monitoring human healthcare and exercise intensity.


Assuntos
Técnicas Biossensoriais , Polímeros , Humanos , Suor , Pirróis , Têxteis
7.
Medicine (Baltimore) ; 102(52): e36807, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38206734

RESUMO

Here we assessed the accuracy of O-arm navigation assisted by Wiltse approach to improve based pedicle screw insertion in ankylosing spondylitis combined with thoracolumbar fractures. We then compared it with the freehand pedicle screw insertion technique. The study sample included 32 patients with ankylosing spondylitis combined with thoracolumbar fractures. Pedicle screw reduction and internal fixation was performed under an O-arm navigation system assisted by a Wiltse approach-combined osteotomy ("navigation group," n = 17) and posterior pedicle screw reduction and internal fixation was performed using freehand technique combined osteotomy ("freehand group," n = 15). We then compared the operation time and bleeding volume between the 2 groups. The visual analog scale (VAS) and Oswestry disability index (ODI) were then used to evaluate the clinical efficacy and the kyphosis Cobb angle was used to evaluate the radiological efficacy before operation, 3 days after operation and after the last follow-up. All complications were noted when detected. Finally, classification of screw positions as proposed by Neo et al was used to evaluate the relationship of the position between the screw, the bone cortex, and the incidence of screw penetration. All patients were followed up for 18 to 36 months (i.e., 24.2 ±â€…3.5 months). The operation time and intraoperative bleeding volume of the navigation group were significantly shorter (lower) than those of the freehand group (P < .05). In addition, Both groups showed significantly decreased VAS, ODI, and Cobb angle 3 days after the operation and at the last follow-up when compared to values recorded pre-operation. However, we found no significant difference in VAS, ODI, and Cobb angle between the 2 groups (P > .05). We identified no complications (e.g., infection, VTE/PE, or nerve injury). Moreover, the pedicle screw placement position of the navigation group was better than that of the freehand group (P < .05), and the screw cortical penetration rate was lower than the freehand group (P < .05). During the process of posterior pedicle screw placement, O-arm navigation assisted by the Wiltse approach can significantly reduce operation time, minimize the amount of bleeding volume, and enhance the accuracy of pedicle screw implantation.


Assuntos
Fraturas Ósseas , Parafusos Pediculares , Fraturas da Coluna Vertebral , Espondilite Anquilosante , Cirurgia Assistida por Computador , Humanos , Fraturas da Coluna Vertebral/cirurgia , Espondilite Anquilosante/complicações , Espondilite Anquilosante/cirurgia , Imageamento Tridimensional , Vértebras Lombares/cirurgia , Vértebras Lombares/lesões , Vértebras Torácicas/cirurgia , Vértebras Torácicas/lesões , Tomografia Computadorizada por Raios X , Fixação Interna de Fraturas/métodos , Resultado do Tratamento , Estudos Retrospectivos
8.
Phys Chem Chem Phys ; 24(23): 14424-14429, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35648431

RESUMO

We innovatively used a polypropylene (PP) separator as a substrate and PEO-LiTFSI-SN as a paste to coat on both of the PP surfaces, and formed a sandwich-like solid polymer electrolyte (SPE). The SPE shows a conductivity of 4.22 × 10-3 S cm-1 at room temperature and 7.75 × 10-5 S cm-1 at 0 °C. The pyrene-4,5,9,10-tetraone (PTO)||SPE||Li battery shows a maximum discharge specific capacity of 187.8 mA h g-1 at a current density of 20 mA g-1 under 0 °C. After 100 cycles, the capacity could still be obtained at 88.4 mA h g-1, and the coulombic efficiency stayed stable at 98%. This work paved a new way for the development of solid-state organic batteries (SSOBs) at low temperatures.

9.
Anal Chem ; 94(41): 14109-14117, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-35727990

RESUMO

Single-atom catalysis is mainly focused on its dispersed high-density catalytic sites, but delicate designs to realize a unique catalysis mechanism in terms of target reactions have been much less investigated. Herein an iron single atomic site catalyst anchored on 2-D N-doping graphene (Fe-SASC/G) was synthesized and further employed as a biomimetic sensor to electrochemically detect hydrogen peroxide, showing an extremely high sensitivity of 3214.28 µA mM-1 cm-2, which is much higher than that (6.5 µA mM-1 cm-2) of its dispersed on 1-D carbon nanowires (Fe-SASC/NW), ranking the best sensitivity among all reported Fe based catalyst at present. The sensor was also used to successfully in situ monitor H2O2 released from A549 living cells. The mechanism was further systematically investigated. Results interestingly indicate that the distance between adjacent single Fe atomic catalytic sites on 2-D graphene of Fe-SASC/G matches statistically well with the outer length of bioxygen of H2O2 to promote a bridge adsorption of -O-O- for simultaneous 2-electron transfer, while the single Fe atoms anchored on distant 1-D nanowires in Fe-SASC/NW only allow an end-adsorption of oxygen atoms for 1-electron transfer. These results demonstrate that Fe-SASC/G holds great promise as an advanced electrode material in selective and sensitive biomimetic sensor and other electrocatalytic applications, while offering scientific insights in deeper single atomic catalysis mechanisms, especially the effects of substrate dimensions on the mechanism.


Assuntos
Grafite , Adsorção , Biomimética , Carbono , Peróxido de Hidrogênio , Ferro , Oxigênio
10.
Adv Sci (Weinh) ; 9(6): e2104066, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34978161

RESUMO

Instability of 2D phosphorene material is the major obstacle for its broad applications. Herein phosphorene is sandwiched with self-assembled iron porphyrin monolayers on both sides (I-Phene) to significantly enhance stability. Iron porphyrin has strong interaction with phosphorene through formation of PFe bonds. The sandwich structure offers excellent stability of phosphorene by both-sided monolayer protections for an intact phosphorene structure more than 40 days under ambient conditions. Meanwhile, the electron transfer between iron porphyrin and phosphorene result in a high oxidation state of Fe, making I-Phene biomimetic sensitivity toward oxidation of nitric oxide (NO) for 2.5 and 4.0 times higher than phosphorene and iron-porphyrin alone, respectively. Moreover, I-Phene exhibits excellent selectivity, a wide detection range, and a low detection limit at a low oxidation potential of 0.82 V, which is comparable with the reported noble metal based biomimetic sensors while ranking the best among all non-noble biomimetic ones. I-Phene is further used for real-time monitoring NO released from cells. This work provides effective approach against phosphorene degrading for outstanding stability, which has universal significance for its various important applications, and holds a great promise for a highly sensitive biomimetic sensor in live-cell assays.


Assuntos
Biomimética/métodos , Técnicas Biossensoriais/métodos , Ferro/metabolismo , Óxido Nítrico/análise , Óxido Nítrico/metabolismo , Porfirinas/metabolismo , Transporte de Elétrons
11.
Chem Commun (Camb) ; 57(73): 9264-9267, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34519295

RESUMO

Hybrid materials were prepared via the controlled fumigation-based polymerization of pyrrole on the surface of activated carbon derived from carbon dots, combining the stability of carbon materials, the wettability of carbon dots, and the high pseudocapacitance of polypyrrole; all of these synergistically boosted the electrochemical performance, resulting in a high specific capacitance (481 F g-1) and good stability for supercapacitor applications.

12.
Anal Chem ; 93(31): 10789-10797, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34212722

RESUMO

Single-atom catalysis efficiently exposes the catalytic sites to reactant molecules while rendering opportunity to investigate the catalysis mechanisms at atomic levels for scientific insights. Here, for the first time, atomically dispersed Co atoms are synthesized as biomimetic "enzymes" to monitor superoxide anions (O2•-), delivering ultraordinary high sensitivity (710.03 µA·µM-1·cm-2), low detection limit (1.5 nM), and rapid response time (1.2 s), ranking the best among all the reported either bioenzymatic or biomimetic O2•- biosensors. The sensor is further successfully employed to real-time monitor O2•- released from living cells. Moreover, theoretical calculation and analysis associated with experimental results discover that a mode of end adsorption of the negatively charged O2•- on the Co3+ atom rather than a bridge or/and side adsorption of the two atoms of O2•- on two Co3+ atoms, respectively, plays an important role in the single-atomic catalysis toward O2•- oxidation, which not only facilitates faster electron transfer but also offers better selectivity. This work holds great promise for an inexpensive and sensitive atomic biomimetic O2•- sensor for bioresearch and clinic diagnosis, while revealing that the adsorption mode plays a critical role in single-atom catalysis for a fundamental insight.


Assuntos
Técnicas Biossensoriais , Adsorção , Catálise , Oxirredução , Superóxidos
13.
ACS Biomater Sci Eng ; 7(7): 3379-3388, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34161086

RESUMO

With the rapid development and advancement in orthodontic and orthopedic technologies, the demand for biomedical-grade titanium (Ti) alloys is growing. The Ti-based implants are susceptible to bacterial infections, leading to poor healing and osteointegration, resulting in implant failure or repeated surgical intervention. Silk sericin (SS) is hydrophilic, biocompatible, and biodegradable and could induce a low immunological response in vivo. As a result, it would be intriguing to investigate the use of hydrophilic SS in surface modification. In this work, the tyrosine moiety in SS was oxidized by tyrosinase (or polyphenol oxidase) to the 3,4-dihydroxyphenylalanine (DOPA) form, generating the catechol moiety-containing SS (SSC). Inspired by the adhesion of mussel foot proteins, the SSC coatings could be directly deposited onto multiple surfaces in SS and tyrosinase mixed stock solutions to create active surfaces with catechol groups. Further, the SSC-coated Ti surfaces were hybridized with silver nanoparticles (Ag NPs) via in situ silver ion (Ag+) reduction. The antibacterial properties of the Ag NPs/SS-coated Ti surfaces are demonstrated, and they can prevent bacterial cell adhesion as well as early-stage biofilm formation. In addition, the developed Ag NPs/SSC-coated Ti surfaces exhibited a negligible level of cytotoxicity in L929 mouse fibroblast cells.


Assuntos
Bivalves , Nanopartículas Metálicas , Sericinas , Adesivos , Animais , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Camundongos , Sericinas/farmacologia , Prata/farmacologia , Staphylococcus aureus
14.
Cell Mol Bioeng ; 14(2): 187-199, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33868499

RESUMO

A fast and low-cost fabrication process of flexible hanging drop chips for 3D spheroid cultures was proposed by cutting and bonding Parafilm®, a cohesive thermoplastic. The Parafilm® Hanging Drop Chip (PHDC) was assembled by two-layer of Parafilm® sheet with different sizes of holes. The hole on the upper layer of the Parafilm® is smaller than the hole on the bottom layer. The impact of hole size and sample volume on hanging drop formation and 3D spheroid formations in the hanging drop were investigated. The results showed that 20 µL solution on PHDC with a 3 mm hole could form stabile drop and facilitate spheroid formation. The initial cell number determinates the size of the formed spheroids. Exchanging liquid from the upper hole of the PHDC enables the co-culture of two types of cells in one spheroid and drug efficacy testing in hanging drops. The relative expression of cell adhesion and hypoxia-related genes from spheroids in hanging drop and conventional culture plate suggested the relevance of 3D spheroids and in vivo tumor tissue. The economical hanging drop chip can be fabricated without wet chemistry or expensive fabrication equipment, strengthening its application potential in conventional biological laboratories.

15.
Colloids Surf B Biointerfaces ; 200: 111592, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33556756

RESUMO

Titanium (Ti) and its alloys are primarily explored to produce biomedical implants owing to their improved mechanical stability, corrosion resistance, low density, and good biocompatibility. Despite, Ti substrate surfaces are easily contaminated by plasma proteins and bacteria. Herein, a simple one-step process for the simultaneous deposition of a polyphenol tannic acid (TA) and four-armed poly(ethylene glycol) (PEG10k-4-OH) on the Ti substrate (Ti-TA/PEG) surface was described. Additionally, a two-step process has been employed to fabricate the Ti-TA-PEG surface via successive deposition of TA and PEG10k-4-OH for comparison. The resultant Ti-TA/PEG surface prepared by simultaneous deposition of TA and PEG10k-4-OH exhibits higher coating thickness and better surface coverage than the Ti-TA-PEG surface. The Ti-TA/PEG and Ti-TA-PEG surfaces could actively inhibit the non-specific adsorption of proteins, suppress the bacterial and platelet adhesion, and prevents biofilm formation. Moreover, the Ti-TA/PEG surface displays a better antifouling performance than the Ti-TA-PEG surface. Thus, the present study demonstrates a simple and convenient approach for constructing polymeric coating with good anti-adhesive properties on the Ti substrate surface.


Assuntos
Incrustação Biológica , Titânio , Incrustação Biológica/prevenção & controle , Polietilenoglicóis , Propriedades de Superfície , Taninos
16.
Antonie Van Leeuwenhoek ; 113(2): 293-301, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31583494

RESUMO

A Gram-stain negative, aerobic, non-flagellated, non-gliding, rod-shaped bacterium, designated strain YLY04T, was isolated from the gut microflora of a sea bass (Dicentrarchus labrax L.) collected from the coast of Yuanyao Wharf, Weihai, China. Growth was found to occur at pH 6.0-9.0 (optimum, 7.0-8.0), 4-37 °C (optimum, 28-30 °C) in the presence of 0-11.0% (w/v) NaCl (optimum, 3.0-4.0%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YLY04T is closely related to Pelagivirga sediminicola BH-SD19T and Roseovarius antarcticus M-S13-148T. Strain YLY04T contains ubiquinone-10 as the sole respiratory quinone and summed feature 8 (C18:1ω7c and/or C18:1ω6c), cyclo-C19:0ω8c, C16:0 and 11-methyl-C18:1ω7c as the major fatty acids. The polar lipids of strain YLY04T were found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid, an unidentified phospholipid and three unidentified lipids. The DNA G+C content was determined to be 62.7 mol%. The phenotypic, chemotaxonomic and phylogenetic properties, and genome analysis, indicated that strain YLY04T represents a novel species within the genus Pelagivirga, for which the name Pelagivirga dicentrarchi sp. nov. is proposed. The type strain is YLY04T (= MCCC 1H00334T = KCTC 62452T).


Assuntos
Bass/microbiologia , Ácidos Graxos/metabolismo , Rhodobacteraceae/genética , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Bass/genética , DNA Bacteriano/genética , Microbioma Gastrointestinal , Genótipo , Fosfolipídeos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Rhodobacteraceae/classificação , Análise de Sequência de DNA
17.
ACS Appl Bio Mater ; 3(11): 7462-7471, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-35019488

RESUMO

Bioscaffolds are important substrates for supporting three-dimensional (3D) cell cultures. Silk fibroin (SF) is an attractive biomaterial in tissue engineering because of its good biocompatibility and mechanical properties. Electrospinning is one of the most often used approaches to fabricate SF fibrous scaffolds; yet, this technique still faces many challenges, such as low yield, residual organic solvents, limited extensibility of fibers, and a lack of spatial control over pore size. To circumvent these limitations, a core-shell SF on rice paper (SF@RP) fibrous scaffold was fabricated using a mild one-step dip-coating method. The cellulose fiber matrix of RP is the physical basis of the 3D scaffold, whereas the SF coating on the cellulose fiber controls the adhesion/spreading of the cells. The results indicated that by tuning the secondary structure of SF on the surface of a SF@RP scaffold, the cell behavior on SF@RP could be tuned. Tumor spheroids can be formed on SF@RP scaffolds with a dominant random secondary structure, in contrast to cells adhering and spreading on SF@RP scaffolds with a higher ratio of ß-sheet secondary structures. Direct culturing of breast cancer MDA-MB-231 and MCF-7, lung cancer A549, prostate cancer DU145, and liver cancer HepG2 cells could spontaneously lead to corresponding tumor spheroids on SF@RP. In addition, the physiological characteristics of HepG2 tumor spheroids were investigated, and the results showed that compared with HepG2 monolayer cells, CYP3A4, CYP1A1, and albumin gene expression levels in HepG2 cell spheres formed on SF@RP scaffolds were significantly higher. Moreover, these spheroids showed higher drug resistance. In summary, these SF@RP scaffolds prepared by the dip-coating method are biocompatible substrates for cell culture, especially for tumor cell spheroid formation.

18.
RSC Adv ; 10(55): 33026-33032, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-35685032

RESUMO

Ionic liquids (ILs) were utilized as iron and phosphorus sources for the preparation of iron phosphide for the first time. The IL trihexyl(tetradecyl)phosphonium tetrachloroferrate ([P(C6H13)3C14H29][FeCl4]) and carbon nanotubes (CNTs) were applied as precursors for the in situ preparation of Fe2P(IL6)/CNTs. This material has good catalytic activity and stability for the hydrogen evolution reaction, including a low onset overpotential (75 mV) and Tafel slope (68 mV dec-1). Moreover, this catalyst exhibits current densities of 10 and 20 mA cm-2 at overpotentials of 115 and 150 mV, respectively. The phosphidation process using [P(C6H13)3C14H29][FeCl4] was also investigated. All experimental results indicate that Fe2P can be formed in situ on the CNTs using this IL, and that the CNTs help the formation of the Fe2P nanoparticles and improve the electrical conductivity. This IL-based in situ preparation strategy is facile and environmentally friendly and does not require the addition of other reagents. This method holds great promise for application in other electrochemical studies.

19.
Theranostics ; 9(21): 6314-6333, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534553

RESUMO

Regenerated silk fibroin (SF) is a type of natural biomacromolecules with outstanding biocompatibility and biodegradability. However, stimulus-responsive SF-based nanocomplex has seldom been reported for application in tumor diagnosis and therapy. Methods: As a proof-of-concept study, a multifunctional SF@MnO2 nanoparticle-based platform was strategically synthesized using SF as a reductant and a template via a biomineralization-inspired crystallization process in an extremely facile way. Because of their mesoporous structure and abundant amino and carboxyl terminal residues, SF@MnO2 nanoparticles were co-loaded with a photodynamic agent indocyanine green (ICG) and a chemotherapeutic drug doxorubicin (DOX) to form a SF@MnO2/ICG/DOX (SMID) nanocomplex. Results: The obtained product was highly reactive with endogenous hydrogen peroxide (H2O2) in tumor microenvironment, which was decomposed into O2 to enhance tumor-specific photodynamic therapy (PDT). Moreover, SMID nanocomplex produced a strong and stable photothermal effect upon near-infrared (NIR) irradiation for photothermal therapy (PTT) owing to the distinct photothermal response of SF@MnO2 and stably conjugated ICG. The concurrent NIR fluorescence and magnetic resonance (MR) imaging in vivo both indicated effective tumor-specific enrichment of SMID nanoparticles via enhanced permeability and retention (EPR) effect. Animal studies further verified that SMID nanoparticles remarkably improved tumor inhibitive efficacy through combination PTT/PDT/chemotherapy with minimal systemic toxicity or adverse effect. Conclusion: This study demonstrated the promising potential of SF-based nanomaterial to address some of the key challenges in cancer therapy due to unfavorable tumor microenvironment for drug delivery.


Assuntos
Doxorrubicina/administração & dosagem , Fibroínas/química , Compostos de Manganês/química , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Óxidos/química , Animais , Biomineralização , Terapia Combinada , Cristalização , Feminino , Humanos , Peróxido de Hidrogênio/química , Verde de Indocianina/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Imagem Óptica , Fotoquimioterapia , Distribuição Tecidual , Microambiente Tumoral
20.
Nanomedicine (Lond) ; 14(17): 2273-2292, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31414615

RESUMO

Aim: Hollow mesoporous copper sulfide nanocapsules conjugated with poly(ethylene glycol) (PEG), doxorubicin and chlorin e6 (HPDC) were synthesized for fluorescence imaging and multimodal tumor therapy. Materials & methods: HPDC were synthesized by encapsulating chlorin e6 and doxorubicin into PEGylated nanocapsules via a simple precipitation method. The photothermal/photodynamic effects, drug release, cellular uptake, imaging capacities and antitumor effects of the HPDCs were evaluated. Results: This smart nanoplatform is stimulus-responsive toward an acidic microenvironment and near infrared laser irradiation. Moreover, fluorescence imaging-guided and combined photothermal/photodynamic/chemotherapies of tumors were promoted under laser activation and led to efficient tumor ablation, as evidenced by exploring animal models in vivo. Conclusion: HPDCs are expected to serve as potent and reliable nanoagents for achieving superior therapeutic outcomes in cancer management.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Doxorrubicina/uso terapêutico , Nanocápsulas/uso terapêutico , Porfirinas/uso terapêutico , Animais , Clorofilídeos , Cobre/uso terapêutico , Feminino , Humanos , Hipertermia Induzida , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Imagem Óptica , Polietilenoglicóis/uso terapêutico , Sulfetos/uso terapêutico , Nanomedicina Teranóstica
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