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1.
J Exp Bot ; 75(5): 1633-1646, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38180121

RESUMEN

The petals of ornamental plants such as roses (Rosa spp.) are the most economically important organs. This delicate, short-lived plant tissue is highly susceptible to pathogens, in large part because the walls of petal cells are typically thinner and more flexible compared with leaf cells, allowing the petals to fold and bend without breaking. The cell wall is a dynamic structure that rapidly alters its composition in response to pathogen infection, thereby reinforcing its stability and boosting plant resistance against diseases. However, little is known about how dynamic changes in the cell wall contribute to resistance to Botrytis cinerea in rose petals. Here, we show that the B. cinerea-induced transcription factor RhbZIP17 is required for the defense response of rose petals. RhbZIP17 is associated with phenylpropanoid biosynthesis and binds to the promoter of the lignin biosynthesis gene RhCAD1, activating its expression. Lignin content showed a significant increase under gray mold infection compared with the control. RhCAD1 functions in the metabolic regulation of lignin production and, consequently, disease resistance, as revealed by transient silencing and overexpression in rose petals. The WRKY transcription factor RhWRKY30 is also required to activate RhCAD1 expression and enhance resistance against B. cinerea. We propose that RhbZIP17 and RhWRKY30 increase lignin biosynthesis, improve the resistance of rose petals to B. cinerea, and regulate RhCAD1 expression.


Asunto(s)
Rosa , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Rosa/genética , Lignina/metabolismo , Regulación de la Expresión Génica , Botrytis/fisiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas
2.
Small ; 19(24): e2207252, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36922734

RESUMEN

The abnormal pressure in tumor tissue is a significant limitation on the drug delivery efficiency of tumor therapy. This work reports a gradient-driven nanomotor as drug nanocarrier with the pressure-counterworking function. The dual-fuel nanomotors are formed by co-electrospinning of the photosensitive polymers with calcium peroxide (CaO2 ) and catalase (CAT), followed by ultraviolet (UV) irradiation and bovine serum albumin (BSA) incubation. The UV-responsive cleavage nanomotors can effectively release O2 molecules at the fractures as a driving force to increase the delivery speed and escape the phagocytosis of macrophage system in normal tissues. Furthermore, CAT catalyzes H2 O2 produced by CaO2 and the tumor interstitial fluids to provide stronger power for the nanomotors. Additionally, according to the analysis of directional motions of the nanomotors, the functional relationship between the rotational diffusion coefficient (DR ) and the physiological viscosity is constructed. The dual-fuel nanocarriers enable up to 13.25% of the injected dose (ID)/per gram tissue and significantly improve the penetration in deep tumor. It is of vital importance to design and obtain the adaptive pressure-gradient counterworking nanomotors, which can effectively improve the drug delivery efficiency in vitro and in vivo.


Asunto(s)
Sistemas de Liberación de Medicamentos , Líquido Extracelular , Preparaciones Farmacéuticas , Polímeros
3.
Chemistry ; 27(36): 9360-9371, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-33831265

RESUMEN

Stimuli-responsive chromic materials such as photochromics, hydrochromics, thermochromics, and electrochromics have a long history of capturing the attention of scientists due to their potential industrial applications and novelty in popular culture. However, hybrid chromic materials that combine two or more stimuli-triggered color changing properties are not so well known. Herein, we report a design strategy that has led to a series of emissive 1,8-naphthalimide-viologen dyads which exhibit unusual dual photochromic and hydrochromic switching behavior in the solid-state when embedded in a cellulose matrix. This behavior manifests as reversible solid state fluorescence hydrochromism upon changes in atmospheric relative humidity (RH), and reversible solid state photochromism upon generation of a cellulose-stabilized viologen radical cation. In this design strategy, the bipyridinium unit serves as both a water-sensitive receptor for the hydrochromic fluorophore-receptor system, and a photochromic group, capable of eliciting its own visible colorimetric response, generating a fluorescence quenching radical cation with prolonged exposure to ultraviolet (UV) light. These dyes can be inkjet-printed onto cellulose paper or drop-cast as cellulose powder-based films and can be unidirectionally cycled between three different states which can be characteristically visualized under UV light or visible light. The material's photochromism, hydrochromism, and underlying mechanism of action was investigated using computational analysis, dynamic vapor sorption/desorption isotherms, electron paramagnetic resonance spectroscopy, and variable humidity UV-Vis adsorption and fluorescence spectroscopies.


Asunto(s)
Naftalimidas , Viológenos , Celulosa , Luz , Rayos Ultravioleta
4.
Nat Chem Biol ; 15(8): 830-837, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31320758

RESUMEN

Non-vesicular lipid transport between bilayers at membrane contact sites plays important physiological roles. Mechanistic insight into the action of lipid-transport proteins localized at these sites requires determination of the distance between bilayers at which this transport can occur. Here we developed DNA-origami nanostructures to organize size-defined liposomes at precise distances and used them to study lipid transfer by the synaptotagmin-like mitochondrial lipid-binding protein (SMP) domain of extended synaptotagmin 1 (E-Syt1). Pairs of DNA-ring-templated donor and acceptor liposomes were docked through DNA pillars, which determined their distance. The SMP domain was anchored to donor liposomes via an unstructured linker, and lipid transfer was assessed via a Förster resonance energy transfer (FRET)-based assay. We show that lipid transfer can occur over distances that exceed the length of an SMP dimer, which is compatible with the shuttle model of lipid transport. The DNA nanostructures developed here can also be adapted to study other processes occurring where two membranes are closely apposed to each other.


Asunto(s)
ADN/química , Membrana Dobles de Lípidos/química , Lípidos/química , Transporte Biológico , Membrana Celular , Escherichia coli , Metabolismo de los Lípidos , Liposomas/química , Microscopía Electrónica , Nanoestructuras
5.
Nano Lett ; 20(8): 6032-6037, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32648765

RESUMEN

Nanodiscs (ND) are soluble phospholipid bilayers bounded by membrane scaffold proteins; they have become invaluable in the study of membrane proteins. However, this multifunctional tool has been used individually, and applications involving multiple NDs and their interactions have fallen far behind their counterpart membrane model system: liposomes. One major obstacle is the lack of reliable methods to manage the spatial arrangement of NDs. Here we sought to extend the utility of NDs by organizing them on DNA origami. NDs constructed with DNA-anchor amphiphiles were placed precisely and specifically into these DNA nanostructures via hybridization. Four different tethering strategies were explored and validated. A variety of geometric patterns of NDs were successfully programmed on origami, as evidenced by electron microscopy. The ND ensembles generated in this study provide new and powerful platforms to study protein-lipid or protein-protein interactions with spatial control of membranes.


Asunto(s)
ADN , Nanoestructuras , Membrana Dobles de Lípidos , Liposomas , Proteínas de la Membrana , Fosfolípidos
6.
Bull Environ Contam Toxicol ; 107(4): 764-769, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33599786

RESUMEN

Based on the micro-hyperspectral imaging technique, spherical engineered microplastic (polyethylene, 10-45 µm) and microalgae (Isochrysis galbana) (4-7 µm) were identified. In transmittance mode of MHSI, micro image cubes from 400 to 1000 nm were obtained from slides containing MP and MA in thin seawater. Classifiers like Support Vector Machine (SVM(Radial Basis Function (RBF))), Least Squares Support Vector Machine (LSSVM(RBF)), k-Nearest Neighbors, etc. were adopted and compared to classify MP and MA. In order to expand the imaging range of micro imaging, image stitching technology was adopted. In allusion to the stitched image cube, SVM(RBF) is suggested for the identification of MA and MP, with recall and precision > 0.86. The above results demonstrate that the MHSI is a promising technique, which can detect MPs with particle size Limit of Detection of 10-45 µm, and it is potential to further expand this LOD.


Asunto(s)
Haptophyta , Microalgas , Imágenes Hiperespectrales , Microplásticos , Plásticos
7.
Int Ophthalmol ; 41(12): 3903-3910, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34291401

RESUMEN

PURPOSE: To compare safety and effectiveness among methods to remove sticky silicone oil bubbles adhered to the retinal surface. METHODS: This retrospective nonrandomised case series included 14 eyes of 14 patients who had sticky silicone oil residue during silicone oil removal surgery. For small sticky silicone oil bubbles (< 2-disc diameter), aspiration was performed with a 23-gauge vitreous cutter. Residual tiny oil bubbles were then removed with a silicone-tipped flute needle or internal limiting membrane (ILM) peeling. For large sticky silicone oil bubbles (≥ 2-disc diameter) that could not be removed with a 23-gauge vitreous cutter, we devised a more efficient active removal method involving a modified 22-gauge venous indwelling cannula device. RESULTS: The mean preoperative best-corrected visual acuity (BCVA; logarithm of the minimum angle of resolution [logMAR]) significantly improved from 1.28 ± 0.63 logMAR to 0.77 ± 0.58 logMAR (p = 0.014). The postoperative BCVA and improvement in BCVA were significantly better in the ILM peeling group than in the non-ILM peeling group (p = 0.004 and p = 0.045, respectively). Postoperative complications included residual sticky silicone oil bubbles in seven eyes without ILM peeling (50.0%), retinal neuroepithelial layer damage in two eyes (14.3%), and temporary hypotony in five eyes (35.7%). CONCLUSION: Various methods can safely and efficiently remove sticky silicone oil bubbles adhered to the retinal surface. A 22-gauge venous indwelling cannula enabled simple and safe removal of large sticky silicone oil bubbles, while small residual sticky silicone oil bubbles could be completely removed by ILM peeling.


Asunto(s)
Desprendimiento de Retina , Perforaciones de la Retina , Membrana Basal , Endotaponamiento , Humanos , Desprendimiento de Retina/cirugía , Perforaciones de la Retina/cirugía , Estudios Retrospectivos , Aceites de Silicona , Tomografía de Coherencia Óptica , Agudeza Visual , Vitrectomía
8.
Nature ; 512(7512): 44-8, 2014 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-25079326

RESUMEN

The evolutionary relationships of extinct species are ascertained primarily through the analysis of morphological characters. Character inter-dependencies can have a substantial effect on evolutionary interpretations, but the developmental underpinnings of character inter-dependence remain obscure because experiments frequently do not provide detailed resolution of morphological characters. Here we show experimentally and computationally how gradual modification of development differentially affects characters in the mouse dentition. We found that intermediate phenotypes could be produced by gradually adding ectodysplasin A (EDA) protein in culture to tooth explants carrying a null mutation in the tooth-patterning gene Eda. By identifying development-based character inter-dependencies, we show how to predict morphological patterns of teeth among mammalian species. Finally, in vivo inhibition of sonic hedgehog signalling in Eda null teeth enabled us to reproduce characters deep in the rodent ancestry. Taken together, evolutionarily informative transitions can be experimentally reproduced, thereby providing development-based expectations for character-state transitions used in evolutionary studies.


Asunto(s)
Evolución Biológica , Fósiles , Diente/anatomía & histología , Diente/crecimiento & desarrollo , Animales , Simulación por Computador , Ectodisplasinas/deficiencia , Ectodisplasinas/genética , Ectodisplasinas/farmacología , Femenino , Eliminación de Gen , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas Hedgehog/genética , Técnicas In Vitro , Masculino , Ratones , Diente Molar/anatomía & histología , Diente Molar/efectos de los fármacos , Diente Molar/crecimiento & desarrollo , Fenotipo , Transducción de Señal/efectos de los fármacos , Diente/efectos de los fármacos
9.
Microb Cell Fact ; 17(1): 102, 2018 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-29970091

RESUMEN

BACKGROUND: High production cost of bioplastics polyhydroxyalkanoates (PHA) is a major obstacle to replace traditional petro-based plastics. To address the challenges, strategies towards upstream metabolic engineering and downstream fermentation optimizations have been continuously pursued. Given that the feedstocks especially carbon sources account up to a large portion of the production cost, it is of great importance to explore low cost substrates to manufacture PHA economically. RESULTS: Escherichia coli was metabolically engineered to synthesize poly-3-hydroxybutyrate (P3HB), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB), and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) using acetate as a main carbon source. Overexpression of phosphotransacetylase/acetate kinase pathway was shown to be an effective strategy for improving acetate assimilation and biopolymer production. The recombinant strain overexpressing phosphotransacetylase/acetate kinase and P3HB synthesis operon produced 1.27 g/L P3HB when grown on minimal medium supplemented with 10 g/L yeast extract and 5 g/L acetate in shake flask cultures. Further introduction succinate semialdehyde dehydrogenase, 4-hydroxybutyrate dehydrogenase, and CoA transferase lead to the accumulation of P3HB4HB, reaching a titer of 1.71 g/L with a 4-hydroxybutyrate monomer content of 5.79 mol%. When 1 g/L of α-ketoglutarate or citrate was added to the medium, P3HB4HB titer increased to 1.99 and 2.15 g/L, respectively. To achieve PHBV synthesis, acetate and propionate were simultaneously supplied and propionyl-CoA transferase was overexpressed to provide 3-hydroxyvalerate precursor. The resulting strain produced 0.33 g/L PHBV with a 3-hydroxyvalerate monomer content of 6.58 mol%. Further overexpression of propionate permease improved PHBV titer and 3-hydroxyvalerate monomer content to 1.09 g/L and 10.37 mol%, respectively. CONCLUSIONS: The application of acetate as carbon source for microbial fermentation could reduce the consumption of food and agro-based renewable bioresources for biorefineries. Our proposed metabolic engineering strategies illustrate the feasibility for producing polyhydroxyalkanoates using acetate as a main carbon source. Overall, as an abundant and renewable resource, acetate would be developed into a cost-effective feedstock to achieve low cost production of chemicals, materials, and biofuels.


Asunto(s)
Acetatos/metabolismo , Escherichia coli/metabolismo , Ingeniería Metabólica , Polihidroxialcanoatos/biosíntesis , Ácido 3-Hidroxibutírico/biosíntesis , Acetato Quinasa/genética , Técnicas de Cultivo Celular por Lotes , Biopolímeros/biosíntesis , Carbono/metabolismo , Escherichia coli/genética , Fermentación , Fosfato Acetiltransferasa/genética , Plásticos
10.
J Biol Chem ; 288(11): 7769-7780, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23341457

RESUMEN

Membrane fusion for exocytosis is mediated by SNAREs, forming trans-ternary complexes to bridge vesicle and target membranes. There is an array of accessory proteins that directly interact with and regulate SNARE proteins. PRIP (phospholipase C-related but catalytically inactive protein) is likely one of these proteins; PRIP, consisting of multiple functional modules including pleckstrin homology and C2 domains, inhibited exocytosis, probably via the binding to membrane phosphoinositides through the pleckstrin homology domain. However, the roles of the C2 domain have not yet been investigated. In this study, we found that the C2 domain of PRIP directly interacts with syntaxin 1 and SNAP-25 but not with VAMP2. The C2 domain promoted PRIP to co-localize with syntaxin 1 and SNAP-25 in PC12 cells. The binding profile of the C2 domain to SNAP-25 was comparable with that of synaptotagmin I, and PRIP inhibited synaptotagmin I in binding to SNAP-25 and syntaxin 1. It was also shown that the C2 domain was required for PRIP to suppress SDS-resistant ternary SNARE complex formation and inhibit high K(+)-induced noradrenalin release from PC12 cells. These results suggest that PRIP inhibits regulated exocytosis through the interaction of its C2 domain with syntaxin 1 and SNAP-25, potentially competing with other SNARE-binding, C2 domain-containing accessory proteins such as synaptotagmin I and by directly inhibiting trans-SNARE complex formation.


Asunto(s)
Coactivadores de Receptor Nuclear/fisiología , Proteína 25 Asociada a Sinaptosomas/metabolismo , Sintaxina 1/química , Animales , Catálisis , ADN/química , Exocitosis , Liposomas/química , Microscopía Fluorescente/métodos , Norepinefrina/química , Coactivadores de Receptor Nuclear/química , Células PC12 , Potasio/química , Unión Proteica , Estructura Terciaria de Proteína , Ratas , Proteínas Recombinantes/química , Proteínas SNARE/química , Sinaptotagmina I/química
11.
J Am Chem Soc ; 136(31): 11115-20, 2014 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-25051012

RESUMEN

Optical detection of molecular targets typically requires immobilization, separation, or chemical or enzymatic processing. An important exception is aptamers that allow optical detection in solution based on conformational changes. This method, however, requires the laborious selection of aptamers with high target specificity and affinity, and the ability to undergo the required conformational changes. Here we report on an alternative generic scheme for detecting small molecules and proteins in solution based on a shift in the equilibrium of DNA-based strand displacement competition reaction. The shift occurs upon binding of a protein, for example, an antibody to its target. We demonstrate nanomolar detection of small molecules such as biotin, digoxigenin, vitamin D, and folate, in buffer and in plasma. The method is flexible, and we also show nanomolar detection of the respective antibodies or protein targets of these molecules. The detection scheme provides a generic alternative to aptamers for detection of analytes.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/metabolismo , Proteínas/análisis , Unión Competitiva , Biotina/análisis , Análisis Químico de la Sangre , Electroquímica , Transferencia Resonante de Energía de Fluorescencia , Proteínas/metabolismo , Saliva/química , Estreptavidina/análisis
12.
Int J Biol Macromol ; 257(Pt 2): 128755, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38092115

RESUMEN

The practical applications of waterborne epoxy coatings are limited due to their poor barrier properties caused by the formation of numerous micropores and defects during the curing process. Herein, cellulose nanocrystals (CNCs)-reinforced waterborne epoxy coatings were fabricated by the direct addition of 0.2-1.0 wt% CNCs to waterborne epoxy emulsion followed by amine curing agent addition and spray coating. The incorporation of 0.2-0.5 wt% CNCs had no discernible impact on the stability of the waterborne epoxy emulsion. This led to the uniform dispersion of CNCs in the cured coating matrix, as evidenced by differential scanning calorimetry analysis. Because of the good compatibility, 0.2-0.5 wt% CNCs-reinforced epoxy coatings exhibited superior corrosion protection performance for steels. The impedance modulus of these coatings remained at 108 Ω cm2 after being immersed in a 3.5 wt% NaCl solution for 21 d. The hydroxyl groups present on the CNC surface undergo a reaction with the epoxy group, enhancing intermolecular interaction and leading to the formation of a defect-free dense structure that improves coating barrier properties. However, the incorporation of an excessive amount of CNCs (i.e., 0.8 and 1.0 wt%) significantly compromised the corrosion resistance of epoxy coatings due to aggregation-induced coating defects. Overall, this study provides a facile and green strategy for corrosion resistance improvement of waterborne epoxy coatings.


Asunto(s)
Nanopartículas , Acero , Corrosión , Emulsiones , Celulosa , Resinas Epoxi
13.
Zhongguo Gu Shang ; 37(6): 5715-5, 2024 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-38910379

RESUMEN

OBJECTIVE: To explore dose-effect relationship of biomechanical parameters in treating atlantoaxial joint disorder by slimming manipulation. METHODS: From October 2022 to May 2023, 18 patients with atlantoaxial joint disorders were treated, including 10 males and 8 females;aged from 24 to 27 years old with an average of (25.50±1.10) years old;CT of cervical vertebra showed 16 patients with right side distortion and 2 patients with left side distortion. The mechanical parameters of treatment of atlantoaxial joint disorder by tendon relaxation manipulation were measured by wearing massage manipulation gloves. The magnitude, frequency and mechanical curve of force during tendon relaxation and starting force, pulling force, pulling time and mechanical curve during rehabilitation were quantified, the differences between the affected and contralateral manipulations were compared. RESULTS: The maximum force and frequency of Fengchi(GB20) on the affected side were (19.82±2.02) N and (116.83±14.49) times/min, and opposite side were (13.87±2.19) N and (188.89±16.03) times/min, respectively. There were statistically difference in the maximum force and frequency of both sides (P<0.05). The maximum force and frequency of Quepen (ST12) on the affected side were (14.44±3.27) N and (139.06±28.47) times/min, and those on the opposite side were (9.41±1.38) N and (142.50±28.47) times/min. There was difference in maximum force on both sides (P<0.05). The starting force, turning force and turning time of the affected side were (14.16±5.98) N, (11.56±6.63) N, (0.14±0.03) S, and the contralateral side were (8.94±3.39) N, (8.30±4.64) N, (0.18±0.04) S, respectively. The difference of starting force, turning force and turning time on both sides were statistically significant (P<0.05). CONCLUSION: By applying a light relaxation force on the affected side, the mechanical balance between cervical vertebrae could be restored, and recovery trend of atlantoaxial joint disorder could be strengthened. On this basis, the atlantoaxial odontoid process could be reversed by applying a light rotation force, which reflects the characteristics of high safety of the manipulation.


Asunto(s)
Articulación Atlantoaxoidea , Humanos , Masculino , Femenino , Adulto , Articulación Atlantoaxoidea/fisiopatología , Tendones/fisiopatología , Fenómenos Biomecánicos , Adulto Joven , Artropatías/fisiopatología , Artropatías/terapia
14.
Nat Commun ; 15(1): 170, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167652

RESUMEN

Practical photodynamic therapy calls for high-performance, less O2-dependent, long-wavelength-light-activated photosensitizers to suit the hypoxic tumor microenvironment. Iridium-based photosensitizers exhibit excellent photocatalytic performance, but the in vivo applications are hindered by conventional O2-dependent Type-II photochemistry and poor absorption. Here we show a general metallopolymerization strategy for engineering iridium complexes exhibiting Type-I photochemistry and enhancing absorption intensity in the blue to near-infrared region. Reactive oxygen species generation of metallopolymer Ir-P1, where the iridium atom is covalently coupled to the polymer backbone, is over 80 times higher than that of its mother polymer without iridium under 680 nm irradiation. This strategy also works effectively when the iridium atom is directly included (Ir-P2) in the polymer backbones, exhibiting wide generality. The metallopolymer nanoparticles exhibiting efficient O2•- generation are conjugated with integrin αvß3 binding cRGD to achieve targeted photodynamic therapy.


Asunto(s)
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes/química , Iridio/química , Hipoxia/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Polímeros/uso terapéutico , Microambiente Tumoral
15.
Adv Mater ; 36(23): e2314163, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38423019

RESUMEN

Hydrogels are considered as promising materials for human-machine interfaces (HMIs) owing to their merits of tailorable mechanical and electrical properties; nevertheless, it remains challenging to simultaneously achieve ultrasoftness, good mechanical robustness and high sensitivity, which are the pre-requisite requirements for wearable sensing applications. Herein, for the first time, this work proposes a universal phase-transition-induced bubbling strategy to fabricate ultrasoft gradient foam-shaped hydrogels (FSHs) with stop holes for high deformability, crack-resistance and sensitive conformal HMIs. As a typical system, the FSH based on polyacrylamide/sodium alginate system shows an ultralow Young's modulus (1.68 kPa), increased sustainable strain (1411%), enhanced fracture toughness (915.6 J m-2), improved tensile sensitivity (21.77), and compressive sensitivity (65.23 kPa-1). The FSHs are used for precisely acquiring and identifying gesture commands of the operator to remotely control a surgical robot for endoscopy and an electric ship in a first-person perspective for cruising, feeding crabs and monitoring the environmental change in real-time.


Asunto(s)
Resinas Acrílicas , Alginatos , Hidrogeles , Dispositivos Electrónicos Vestibles , Hidrogeles/química , Humanos , Resinas Acrílicas/química , Alginatos/química , Módulo de Elasticidad , Resistencia a la Tracción
16.
Clin Oral Investig ; 17(9): 2003-10, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23358705

RESUMEN

OBJECTIVE: The purpose of this study is to retrospectively explore the utilization of coralline hydroxyapatite in maxillary sinus augmentation. METHOD: One hundred and eighteen cases of sinus lift with coralline hydroxyapatite (CHA) were included in this study. In detail, simultaneous implantation was conducted in 78 patients (174 implants) and delayed implantation was done in 40 cases (82 implants) around 6 months after bone transplantation. The clinical features and X-ray radiographs after operation were analyzed to evaluate osseointegration procedures according to a planned medical follow-up. In the delayed group, around 6 months, a bone biopsy was taken just during implant placement in order to evaluate the new formed bone from a histological and histomorphometrical point of view. A further 6 months later, abutment connection was performed, and the patients received prosthetic restoration of the missing teeth. RESULT: Clinically, the incisions healed well. No abnormal reactions were found during follow-up period. All the 174 simultaneous implants were successful after 1-5 years of medical review; Out of 82 delayed implants, 3 were found to be loose. Histologically, all the specimens showed signs of active remodeling, and all the tissues had a large amount of osteocyte at sixth month after sinus augmentation. New bone formed dramatically. Radiologically, the density of CHA gradually reduced since the beginning of the third month, and CHA may be completely resolved at about fifth year. CONCLUSION: CHA is proven an ideal bone graft material for its reliable clinical results and favorable histocompatibility in the treatment of sinus atrophy or other kinds of insufficient bone volume in this region. Moreover, CHA's signal application can achieve desired clinical effect. CLINICAL RELEVANCE: This study shows the clinic application of CHA in maxillary sinus augmentation. Compared with popular mixture of autogenous bone and grafting materials, our results show CHA's signal application can achieve ideal osseointegration interface and satisfying clinic effect.


Asunto(s)
Cerámica/farmacología , Hidroxiapatitas/farmacología , Elevación del Piso del Seno Maxilar , Humanos , Estudios Retrospectivos
17.
Int J Biol Macromol ; 243: 125106, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37257546

RESUMEN

Lignin nanoparticles (LNPs) have become a hot topic recently because of their improved physicochemical properties and the excellent integration into various industrial sectors compared to lignin. However, the green large-scale production of stable LNPs severely restricts the high-value applications of LNPs. In this work, a simple and potentially scalable continuous-flow mode setup with a tubular flow reactor was designed for the green preparation of stable alkali LNPs assisted by ultrasound. When the flow rates of lignin solution and nitric acid solution were 8.00 mL/min and 2.67 mL/min respectively, and the length of the tube was 5.5 m, the average residence time of mixed solution was 62.2 s in the tubular reactor. Spheroid nanoparticles with an average size of 97.2 nm were obtained under this optimized condition. Furthermore, the results showed a better control of the mixing compared to the batch process, resulting in a homogeneous distribution of smaller particle sizes thus improving stability and UV-blocking properties. This is attributed to the better mixing and excellent mass transfer characteristics in the tube, which provides favorable conditions for the full contact and uniform dispersion of the mixed solution. More importantly, continuous flow mode makes it possible to prepare LNPs with excellent physicochemical properties on a large scale, which will bring great opportunities for the industrial production and application of LNPs.


Asunto(s)
Lignina , Nanopartículas , Lignina/química , Nanopartículas/química
18.
Nat Commun ; 14(1): 1532, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36941256

RESUMEN

Interactions between membrane proteins are essential for cell survival but are often poorly understood. Even the biologically functional ratio of components within a multi-subunit membrane complex-the native stoichiometry-is difficult to establish. Here we demonstrate digital nanoreactors that can control interactions between lipid-bound molecular receptors along three key dimensions: stoichiometric, spatial, and temporal. Each nanoreactor is based on a DNA origami ring, which both templates the synthesis of a liposome and provides tethering sites for DNA-based receptors (modelling membrane proteins). Receptors are released into the liposomal membrane using strand displacement and a DNA logic gate measures receptor heterodimer formation. High-efficiency tethering of receptors enables the kinetics of receptors in 1:1 and 2:2 absolute stoichiometries to be observed by bulk fluorescence, which in principle is generalizable to any ratio. Similar single-molecule-in-bulk experiments using DNA-linked membrane proteins could determine native stoichiometry and the kinetics of membrane protein interactions for applications ranging from signalling research to drug discovery.


Asunto(s)
Membrana Dobles de Lípidos , Liposomas , Membrana Dobles de Lípidos/metabolismo , Proteínas de la Membrana/metabolismo , Nanotecnología , ADN , Proteínas Portadoras
19.
Adv Healthc Mater ; 12(6): e2202663, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36653312

RESUMEN

Ferroptosis, characterized by the accumulation of reactive oxygen species and lipid peroxides, has emerged as an attractive strategy to reverse drug resistance. Of particular interest is the ferroptosis-apoptosis combination therapy for cancer treatment. Herein, a nanoplatform is reported for effective co-delivery of the anticancer drug sorafenib (S) and the ferroptosis inducer hemin (H), toward synergistic ferroptosis-apoptosis therapy of advanced hepatocellular carcinoma (HCC) as a proof-of-concept study. Liposome is an excellent delivery system; however, it is not sufficiently responsive to the acidic tumor microenvironment (TME) for tumor-targeted drug delivery. The pH-sensitive vesicles are therefore developed (SH-AD-L) by incorporating amphiphilic dendrimers (AD) into liposomes for controlled and pH-stimulated release of sorafenib and hemin in the acidic TME, thanks to the protonation of numerous amine functionalities in AD. Importantly, SH-AD-L not only blocked glutathione synthesis to disrupt the antioxidant system, but also increased intracellular Fe2+ and ·OH concentrations to amplify oxidative stress, both of which contribute to enhanced ferroptosis. Remarkably, high levels of ·OH also augmented sorafenib-mediated apoptosis in tumor cells. This study demonstrates the efficacy of ferroptosis-apoptosis combination therapy, as well as the promise of the AD-doped TME-responsive vesicles for drug delivery in combination therapy to treat advanced HCC.


Asunto(s)
Carcinoma Hepatocelular , Dendrímeros , Ferroptosis , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Sorafenib/farmacología , Sorafenib/uso terapéutico , Dendrímeros/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Hemina/farmacología , Hemina/uso terapéutico , Apoptosis , Liposomas/farmacología , Polímeros/farmacología , Concentración de Iones de Hidrógeno , Línea Celular Tumoral , Microambiente Tumoral
20.
Nat Commun ; 14(1): 5256, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37644062

RESUMEN

Small unilamellar vesicles (SUVs) are indispensable model membranes, organelle mimics, and drug and vaccine carriers. However, the lack of robust techniques to functionalize or organize preformed SUVs limits their applications. Here we use DNA nanostructures to coat, cluster, and pattern sub-100-nm liposomes, generating distance-controlled vesicle networks, strings and dimers, among other configurations. The DNA coating also enables attachment of proteins to liposomes, and temporal control of membrane fusion driven by SNARE protein complexes. Such a convenient and versatile method of engineering premade vesicles both structurally and functionally is highly relevant to bottom-up biology and targeted delivery.


Asunto(s)
Liposomas , Nanoestructuras , Humanos , Vesícula , ADN , Ingeniería , Polímeros
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