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1.
BMC Plant Biol ; 24(1): 26, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172661

RESUMEN

To investigate the relationship between stem puncture mechanical characteristics and NK stress diagnosis, the microstructure, surface morphology, cellulose and lignin content, puncture mechanical characteristics, and epidermal cell morphology of cucumber stems were measured herein. The results indicated that the middle stem, which had a diameter of approximately 7000 µm, was more suitable for puncturing due to its lower amount of epidermal hair, and its gradual regularity in shape. Further, the cucumber stems were protected from puncture damage due to their ability to rapidly heal within 25 h.. The epidermal penetration of the cucumber stems increased with the increase in cellulose and lignin, though cellulose played a more decisive role. The epidermal break distance increased with an increase in N application and decreased with an increase in K+ application, but the change in intercellular space caused by K+ supply was the most critical factor affecting the epidermal break distance. In addition, a decrease in K+ concentration led to a decrease in epidermal brittleness, whereas the factors affecting epidermal toughness were more complex. Finally, we found that although the detection of epidermal brittleness and toughness on nutrient stress was poor under certain treatment, the puncture mechanical characteristics of the stem still had a significant indicative effect on N application rate. Therefore, elucidating of the relationship between the puncture mechanical characteristics of the stems and crop nutritional stress is not only beneficial for promoting stem stress physiology research but also for designing on-site nutritional testing equipment in the future.


Asunto(s)
Cucumis sativus , Cucumis sativus/fisiología , Lignina , Celulosa , Punciones
2.
Chemistry ; 30(30): e202400582, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38501912

RESUMEN

The unique biophysical and biochemical properties of intrinsically disordered proteins (IDPs) and their recombinant derivatives, intrinsically disordered protein polymers (IDPPs) offer opportunities for producing multistimuli-responsive materials; their sequence-encoded disorder and tendency for phase separation facilitate the development of multifunctional materials. This review highlights the strategies for enhancing the structural diversity of elastin-like polypeptides (ELPs) and resilin-like polypeptides (RLPs), and their self-assembled structures via genetic fusion to ordered motifs such as helical or beta sheet domains. In particular, this review describes approaches that harness the synergistic interplay between order-promoting and thermoresponsive building blocks to design hybrid biomaterials, resulting in well-structured, stimuli-responsive supramolecular materials ordered on the nanoscale.


Asunto(s)
Materiales Biocompatibles , Elastina , Péptidos , Materiales Biocompatibles/química , Elastina/química , Elastina/genética , Péptidos/química , Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/genética , Temperatura , Humanos , Proteínas de Insectos
3.
Appl Microbiol Biotechnol ; 108(1): 149, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240797

RESUMEN

In this study, we successfully applied the strategy of combining tandem promoters and tandem signal peptides with overexpressing signal peptidase to efficiently express and produce γ-glutamyl peptidase (GGT) enzymes (BsGGT, BaGGT, and BlGGT) from Bacillus subtilis, Bacillus amyloliquefaciens, and Bacillus licheniformis in Bacillus subtilis ATCC6051Δ5. In order to avoid the problem of instability caused by duplicated strong promoters, we assembled tandem promoters of different homologous genes from different species. To achieve resistance marker-free enzyme in the food industry, we first removed the replication origin and corresponding resistance marker of Escherichia coli from the expression vector. The plasmid was then transformed into the B. subtilis host, and the Kan resistance gene in the expression plasmid was directly edited and silenced using the CRISPR/Cas9n-AID base editing system. As a result, a recombinant protein expression carrier without resistance markers was constructed, and the enzyme activity of the BlGGT strain during shake flask fermentation can reach 53.65 U/mL. The recombinant BlGGT was immobilized with epoxy resin and maintained 82.8% enzyme activity after repeated use for 10 times and 87.36% enzyme activity after storage at 4 °C for 2 months. The immobilized BlGGT enzyme was used for the continuous synthesis of theanine with a conversion rate of 65.38%. These results indicated that our approach was a promising solution for improving enzyme production efficiency and achieving safe production of enzyme preparations in the food industry. KEY POINTS: • Efficient expression of recombinant proteins by a combination of dual promoter and dual signal peptide. • Construction of small vectors without resistance markers in B. subtilis using CRISPR/Cas9n-AID editing system. • The process of immobilizing BlGGT with epoxy resin was optimized.


Asunto(s)
Bacillus licheniformis , Bacillus subtilis , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , gamma-Glutamiltransferasa/genética , gamma-Glutamiltransferasa/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Resinas Epoxi , Bacillus licheniformis/genética , Proteínas Recombinantes/genética , Enzimas Inmovilizadas/metabolismo
4.
BMC Pulm Med ; 24(1): 159, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561695

RESUMEN

Cisplatin (DDP) resistance, often leading to first-line chemotherapy failure in non-small cell lung cancer (NSCLC), poses a significant challenge. MiR-219a-5p has been reported to enhance the sensitivity of human NSCLC to DDP. However, free miR-219a-5p is prone to degradation by nucleases in the bloodstream, rendering it unstable. In light of this, our study developed an efficient nanodrug delivery system that achieved targeted delivery of DDP and miR-219a-5p by modifying liposomes with folate (FA). Based on the results of material characterization, we successfully constructed a well-dispersed and uniformly sized (approximately 135.8 nm) Lipo@DDP@miR-219a-5p@FA nanodrug. Agarose gel electrophoresis experiments demonstrated that Lipo@DDP@miR-219a-5p@FA exhibited good stability in serum, effectively protecting miR-219a-5p from degradation. Immunofluorescence and flow cytometry experiments revealed that, due to FA modification, Lipo@DDP@miR-219a-5p@FA could specifically bind to FA receptors on the surface of tumor cells (A549), thus enhancing drug internalization efficiency. Safety evaluations conducted in vitro demonstrated that Lipo@DDP@miR-219a-5p@FA exhibited no significant toxicity to non-cancer cells (BEAS-2B) and displayed excellent blood compatibility. Cellular functional experiments, apoptosis assays, and western blot demonstrated that Lipo@DDP@miR-219a-5p@FA effectively reversed DDP resistance in A549 cells, inhibited cell proliferation and migration, and further promoted apoptosis. In summary, the Lipo@DDP@miR-219a-5p@FA nanodrug, through specific targeting of cancer cells and reducing their resistance to DDP, significantly enhanced the anti-NSCLC effects of DDP in vitro, providing a promising therapeutic option for the clinical treatment of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Cisplatino/farmacología , Cisplatino/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Liposomas/uso terapéutico , MicroARNs/genética , MicroARNs/metabolismo , Resistencia a Antineoplásicos , Línea Celular Tumoral , Proliferación Celular
5.
Adv Neonatal Care ; 24(3): 291-300, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38815280

RESUMEN

BACKGROUND: Neonates experience varying intensities of pain after surgery. While white noise has been used for postoperative pain relief in infants, its effects on neonates after surgery need further exploration. PURPOSE: This study aimed to evaluate the effects of white noise on pain scores and salivary cortisol levels in surgical neonates. METHODS: In this randomized controlled trial, 64 neonates scheduled for surgery were recruited and assigned by block randomization into 2 groups. The intervention group listened to white noise at 50 dB, while the control group listened to white noise at 0 dB, for 30 minutes 6 times for 48 hours postoperatively. Pain scores, measured by the COMFORTneo Scale, and salivary cortisol levels were compared. RESULTS: Although pain scores decreased after surgery in all subjects, no statistically significant difference was observed between the 2 groups (P = .937). There was a significant difference between pre- and postintervention pain scores in the intervention group only (P = .006). Salivary cortisol levels decreased after intervention in the intervention group, but there was no significant difference between pre- and postintervention levels in the 2 groups (P = .716). IMPLICATIONS FOR PRACTICE: Given the reduction in pain scores and salivary cortisol concentrations after white noise intervention, white noise shows potential as an adjunctive soothing measure for neonates after surgery. IMPLICATIONS FOR RESEARCH: Future studies are needed to confirm the efficacy and utility of white noise intervention in clinical settings.


Asunto(s)
Hidrocortisona , Ruido , Dimensión del Dolor , Dolor Postoperatorio , Saliva , Humanos , Hidrocortisona/análisis , Hidrocortisona/metabolismo , Recién Nacido , Saliva/química , Dolor Postoperatorio/metabolismo , Femenino , Masculino , Dimensión del Dolor/métodos , Ruido/efectos adversos
6.
Molecules ; 29(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731558

RESUMEN

Given the widespread prevalence of viruses, there is an escalating demand for antimicrobial composites. Although the composite of dialdehyde cellulose and silver nanoparticles (DAC@Ag1) exhibits excellent antibacterial properties, its weak mechanical characteristics hinder its practical applicability. To address this limitation, cellulose nanofibers (CNFs) were initially ammoniated to yield N-CNF, which was subsequently incorporated into DAC@Ag1 as an enhancer, forming DAC@Ag1/N-CNF. We systematically investigated the optimal amount of N-CNF and characterized the DAC@Ag1/N-CNF using FT-IR, XPS, and XRD analyses to evaluate its additional properties. Notably, the optimal mass ratio of N-CNF to DAC@Ag1 was found to be 5:5, resulting in a substantial enhancement in mechanical properties, with a 139.8% increase in tensile elongation and a 33.1% increase in strength, reaching 10% and 125.24 MPa, respectively, compared to DAC@Ag1 alone. Furthermore, the inhibition zones against Escherichia coli and Staphylococcus aureus were significantly expanded to 7.9 mm and 15.9 mm, respectively, surpassing those of DAC@Ag1 alone by 154.8% and 467.9%, indicating remarkable improvements in antimicrobial efficacy. Mechanism analysis highlighted synergistic effects from chemical covalent bonding and hydrogen bonding in the DAC@Ag1/N-CNF, enhancing the mechanical and antimicrobial properties significantly. The addition of N-CNF markedly augmented the properties of the composite film, thereby facilitating its broader application in the antimicrobial field.


Asunto(s)
Celulosa , Escherichia coli , Nanopartículas del Metal , Plata , Staphylococcus aureus , Plata/química , Nanopartículas del Metal/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Celulosa/química , Celulosa/análogos & derivados , Antibacterianos/farmacología , Antibacterianos/química , Nanofibras/química , Nanocompuestos/química , Pruebas de Sensibilidad Microbiana , Antiinfecciosos/química , Antiinfecciosos/farmacología , Espectroscopía Infrarroja por Transformada de Fourier
7.
BMC Gastroenterol ; 23(1): 235, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37438761

RESUMEN

BACKGROUND: This study was performed to compare a metal stent (MS) and plastic stent (PS) in terms of efficacy and complications during neoadjuvant therapy (NAT) and the perioperative period. METHODS: We performed an electronic search of the following databases until 1 June 2022: PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov. Studies comparing an MS versus PS for PBD in patients with pancreatic cancer undergoing NAT were included. RESULTS: The meta-analysis showed that use of an MS was associated with lower rates of reintervention (p < 0.00001), delay of NAT (p = 0.007), recurrent biliary obstruction (RBO) (p = 0.003), and cholangitis (p = 0.03). There were no significant differences between the two groups in terms of stent migration (p = 0.31), postoperative complications (p = 0.20), leakage (p = 0.90), and R0 resection (p = 0.50). CONCLUSIONS: Use of an MS for PBD in patients with pancreatic cancer undergoing NAT followed by surgery was associated with lower rates of reintervention, delay of NAT, RBO, and cholangitis compared with use of a PS. However, the postoperative outcomes were comparable between the MS and PS. Further studies on this topic are recommended.


Asunto(s)
Colangitis , Colestasis , Neoplasias Pancreáticas , Humanos , Terapia Neoadyuvante , Drenaje , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/cirugía , Metales , Stents/efectos adversos , Colangitis/etiología , Colestasis/etiología , Colestasis/cirugía , Plásticos , Neoplasias Pancreáticas
8.
BMC Pulm Med ; 23(1): 91, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944966

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive disease of the lung. How to build a typical human mimicking animal model has been a challenge. Thus, to reveal the mechanism and to make it useful for IPF clinical treatment, a different type of mice model and inspection methods are used to evaluate which one is applicable for the study of IPF. METHOD: 69 Twelve-weeks-old C57BL/6 mice were divided into 3 type groups (n = 7 for each control group, n = 8 for each BLM-induced pulmonary fibrosis groups), as intraperitoneal injection, intratracheal administration, and intravenous administration of bleomycin (BLM) to initiate lung fibrosis. Changes of the lung function measured through mice Pulmonary function test (PFT). Morphological changes in mice were observed by PET/CT, Masson and Picro-Sirius staining, Transmission electron microscopy (TEM). Biochemical changes were tested by Enzyme-linked immunosorbent assay (Elisa). RESULTS: PET/CT of BLM-receiving mice showed an increase in fibrotic consolidations and an increase in non-aerated lung area in BLM-treated mice compared with that in controls. TGF-b1, TNF-a, IL-6, GM-CSF in BALF and serum. PAI-1, HYP in the lung tissue of mice were significantly different in each BLM groups than those in the controls. The results of Masson staining in mice indicate that the lung tissues of all BLM received groups, the intratracheal groups, the intravenous groups, and the intraperitoneal groups have a higher degree of pulmonary septal thickening and collagen fiber consolidation compare to saline control. Picro-Sirius staining results are consistent with the results of Masson staining. Compared with the saline control group, the ratio of Col 1/Col 3 was significantly increased in each BLM group. TEM results found that in BLM group, type I alveolar epithelial cells were degenerated. Exfoliated endothelial cells were swelling, and type II alveolar epithelial cells were proliferated, the shape of the nucleus was irregular, and some tooth-like protrusions were seen. CONCLUSIONS: With three different methods of animal model construction, high dose of each show more compliable, and BLM can successfully induce animal models of pulmonary fibrosis, however, certain differences in the fibrosis formation sites of them three, and tail vein injection of BLM induced PF model is closer to the idiopathic pulmonary interstitial fibrosis.


Asunto(s)
Bleomicina , Fibrosis Pulmonar Idiopática , Ratones , Humanos , Animales , Bleomicina/toxicidad , Células Endoteliales , Tomografía Computarizada por Tomografía de Emisión de Positrones , Líquido del Lavado Bronquioalveolar , Ratones Endogámicos C57BL , Pulmón , Fibrosis Pulmonar Idiopática/inducido químicamente , Modelos Animales de Enfermedad
9.
Molecules ; 28(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36838845

RESUMEN

The charge plays an important role in cellulose nanocrystal (CNC) self-assembly to form liquid crystal structures, which has rarely been systematically explored. In this work, a novel technique combining atomic force microscopy force and atomistic molecular dynamics simulations was addressed for the first time to systematically investigate the differences in the CNC self-assembly caused by external positive and negative charges at the microscopic level, wherein sodium polyacrylate (PAAS) and chitosan oligosaccharides (COS) were used as external positive and negative charge additives, respectively. The results show that although the two additives both make the color of CNC films shift blue and eventually disappear, their regulatory mechanisms are, respectively, related to the extrusion of CNC particles by PAAS and the reduction in CNC surface charge by COS. The two effects both decreased the spacing between CNC particles and further increased the cross angle of CNC stacking arrangement, which finally led to the color variations. Moreover, the disappearance of color was proved to be due to the kinetic arrest of CNC suspensions before forming chiral nematic structure with the addition of PAAS and COS. This work provides an updated theoretical basis for the detailed disclosure of the CNC self-assembly mechanism.


Asunto(s)
Celulosa , Nanopartículas , Celulosa/química , Nanopartículas/química
10.
Small ; 18(49): e2204199, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36284474

RESUMEN

Currently, the smart photonic materials that can switch circularly polarized signals in real-time have attracted extensive attention due to numerous potential applications in information storage and photonics displays. However, the dynamically reversible switching of circularly polarized signals requires precise structural reconfiguration, which is rarely achieved in traditional biomaterials. Herein, a dual photonic bandgap (PBG) structure is constructed based on the optical propagation principle of cellulose-based photonic crystals, enabling the flexible switching of the intensity, wavelength, and direction of circularly polarized luminescence (CPL). By adjusting the fluorescence intensity and the matching degree of chiral structure, the asymmetric factor value of dual PBG structure is up to -1.47, far exceeding other cellulose-based materials. Importantly, it is demonstrated that dual CPL emission can be efficiently induced by two different PBGs, opening a new approach for on-demand switching of single and dual CPL emission. In addition, the dual PBG structure exhibits dual circularly polarized reflected signals under the circular polarizer, which perfectly embodies the applicability of multiple encryptions in QR codes. This work provides new insights into the real-time manipulation of circularly polarized signals by chiral photonic materials.


Asunto(s)
Luminiscencia , Fotones , Materiales Biocompatibles , Celulosa
11.
Phys Rev Lett ; 129(6): 068101, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-36018633

RESUMEN

Fluctuations of synaptic weights, among many other physical, biological, and ecological quantities, are driven by coincident events of two "parent" processes. We propose a multiplicative shot-noise model that can capture the behaviors of a broad range of such natural phenomena, and analytically derive an approximation that accurately predicts its statistics. We apply our results to study the effects of a multiplicative synaptic plasticity rule that was recently extracted from measurements in physiological conditions. Using mean-field theory analysis and network simulations, we investigate how this rule shapes the connectivity and dynamics of recurrent spiking neural networks. The multiplicative plasticity rule is shown to support efficient learning of input stimuli, and it gives a stable, unimodal synaptic-weight distribution with a large fraction of strong synapses. The strong synapses remain stable over long times but do not "run away." Our results suggest that the multiplicative shot-noise offers a new route to understand the tradeoff between flexibility and stability in neural circuits and other dynamic networks.


Asunto(s)
Modelos Neurológicos , Plásticos , Potenciales de Acción , Plasticidad Neuronal , Sinapsis
12.
Langmuir ; 38(44): 13477-13487, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36306177

RESUMEN

The investigation of the strength and toughness of poly(l-lactic acid) (PLLA) monofilaments is essential as the fundamental element of a biodegradable braided stent. However, the determining factor remains poorly addressed with respect to influencing the mechanical behavior of PLLA monofilaments. In this work, the electron beam (EB) with different radiation doses was utilized to sterilize PLLA monofilaments. Properties of the monofilaments, including the breaking strength, elongation at break, molecular weight, orientation, and microstructure of the fracture, were characterized. Results showed that a random chain scission of PLLA resulting from EB during this process could cause the decrease in molecular weight, which led to the decline in breaking strength. Meanwhile, the irradiated monofilaments were found to have almost the same elongation at break below a dose of 30 kGy and declined by 71.41% up to a dose of 48 kGy. It was also found that the ductile fracture connection of the monofilament translated to the brittle fracture by comparing the microstructure without and with sterilization. These phenomena could originate from the destruction of the long molecular chains connecting the crystal plates into shorter ones by radiation. PLLA monofilaments with 0, 30, and 48 kGy were used to braid carotid stents. Compared with a carotid Wallstent, the PLLA stent can better provide radial supporting to the carotid lesion. This study provides preliminary experimental references to evaluate and predict the mechanical performance of PLLA braided stents.


Asunto(s)
Implantes Absorbibles , Poliésteres , Poliésteres/química , Stents , Resistencia a la Tracción
13.
Biomacromolecules ; 23(3): 937-947, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35195416

RESUMEN

The balance between drug efficiency and its side effects on normal tissues is still a challenging problem to be solved in current cancer therapies. Among different strategies, cancer therapeutic methods based on nanomedicine delivery systems have received extensive attention due to their unique advantages such as improved circulation and reduced toxicity of drugs in the body. Herein, we constructed dual-responsive polymeric micelles DOX&ALS@MFM based on an upper critical solution temperature (UCST) polymer to simultaneously combine chemotherapy, photothermal therapy (PTT), and photodynamic therapy (PDT). Amphiphilic block copolymer P(AAm-co-AN)-b-PEI-ss-PEG-FA with a critical point of 42 °C was able to self-assemble into polymeric micelles under physiological conditions, which further encapsulated anticancer drug doxorubicin (DOX) and photosensitizer ALS to obtain drug-loaded micelles DOX&ALS@MFM. Micelles aggregated at tumor sites due to folate targeting and an enhanced permeability retention (EPR) effect. After that, the high intracellular concentration of glutathione (GSH) and near-infrared (NIR) light prompted disassembly of the polymer to release DOX and ALS. ALS not only plays a role in PTT but also produces singlet oxygen, therefore killing tumor cells by PDT. Both in vitro and in vivo studies demonstrated the photothermal conversion and reactive oxygen species generation ability of DOX&ALS@MFM micelles, at the same time as the excellent inhibitory effect on tumor growth with NIR light irradiation. Thus, our research substantiated a new strategy for the biomedical application of UCST polymers in the cited triple modal tumor therapy.


Asunto(s)
Neoplasias , Línea Celular Tumoral , Doxorrubicina , Humanos , Micelas , Neoplasias/tratamiento farmacológico , Polímeros/uso terapéutico , Temperatura
14.
BMC Anesthesiol ; 22(1): 311, 2022 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-36199026

RESUMEN

BACKGROUND: Based on the upper airway anatomy and joint function parameters examined by ultrasound, a multiparameter ultrasound model for difficult airway assessment (ultrasound model) was established, and we evaluated its ability to predict difficult airways. METHODS: A prospective case-cohort study of difficult airway prediction in adult patients undergoing elective surgery with endotracheal intubation under general anesthesia, and ultrasound phantom examination for difficult airway assessment before anesthesia, including hyomental distance, tongue thickness, mandibular condylar mobility, mouth opening, thyromental distance, and modified Mallampati tests, was performed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the effectiveness of the ultrasound model and conventional airway assessment methods in predicting difficult airways. RESULTS: We successfully enrolled 1000 patients, including 51 with difficult laryngoscopy (DL) and 26 with difficult tracheal intubation (DTI). The area under the ROC curve (AUC) for the ultrasound model to predict DL was 0.84 (95% confidence interval [CI]: 0.82-0.87), and the sensitivity and specificity were 0.75 (95% CI: 0.60-0.86) and 0.82 (95% CI: 0.79-0.84), respectively. The AUC for predicting DTI was 0.89 (95% CI: 0.87-0.91), and the sensitivity and specificity were 0.85 (95% CI: 0.65-0.96) and 0.81 (95% CI: 0.78-0.83), respectively. Compared with mouth opening, thyromental distance, and modified Mallampati tests, the ultrasound model predicted a greater AUC for DL (P < 0.05). Compared with mouth opening and modified Mallampati tests, the ultrasound model predicted a greater AUC for DTI (P < 0.05). CONCLUSIONS: The ultrasound model has good predictive performance for difficult airways. TRIAL REGISTRATION: This study is registered on chictr.org.cn (ChiCTR-ROC-17013258); principal investigator: Jianling Xu; registration date: 06/11/2017).


Asunto(s)
Intubación Intratraqueal , Laringoscopía , Adulto , Anestesia General , Estudios de Cohortes , Humanos , Intubación Intratraqueal/métodos , Laringoscopía/métodos , Valor Predictivo de las Pruebas
15.
J Mater Sci Mater Med ; 33(10): 69, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36190565

RESUMEN

Repeat firing produces uncertainty about stabilizing lithium disilicate glass-ceramic (LDGC) material properties, even though prolonged holding time can enhance the mechanical property of LDGC during a single firing cycle. However, the effect of prolonged holding time and repeat firing on the mechanical property and microstructure of LDGC is not fully understood. In the present study, three groups of LDGC material were created: (i) extension of holding time (7 vs. 14 vs. 28 min) at 780-800 °C; (ii) holding time extension (7 vs. 14 min) and dual sintering at 800-820 °C, respectively; (iii) dual sintering with prolonged holding time (7 vs. 14 min) at 820-840 °C. The nano-indenter test revealed that prolonged holding time (14 and 28 min) promoted the enhancement of LDGC hardness and Young's modulus. X-ray photoelectron spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy confirmed that prolonged holding time increased and stabilized LD phase in LDGC, as well as induced residual compressive stress. Scanning electron microscopy showed that prolonged holding time increased LD crystal grains homogeneously and facilitated LDGC to form dense interlocking structure without enlarging crystal size grains significantly. In contrast, LDGC that dual sintered alone at 820-840 °C possessed inferior mechanical properties, coupled with heterogeneous crystal phases, residual tensile stress, and melted crystals grains in the porous microstructure. Interestingly, these deteriorated properties of LDGC caused by dual sintering alone could be counteracted by prolonging the holding time. Nevertheless, the LDGC materials displayed an excellent biocompatibility throughout the study. This study identified that prolonged holding time during repeated firing cycles stabilized LD phase and crystal grain size of LDGC, thus enhanced the mechanical properties, which provided a new insight to extend the repeat fired restoration longevity of LDGC. Graphical abstract.


Asunto(s)
Cerámica , Porcelana Dental , Cerámica/química , Módulo de Elasticidad , Ensayo de Materiales , Propiedades de Superficie
16.
J Craniofac Surg ; 33(6): 1829-1834, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35119416

RESUMEN

OBJECTIVE: To investigate the clinical effect of the supraorbital keyhole approach (SKA) via a forehead wrinkle incision in the resection of tumors in the anterior skull base and sellar region. METHODS: Sixty patients with tumors located in the anterior skull base and sellar region treated through the SKA in our hospital from 2017 to 2020. The skin incision and bone flap position were designed individually according to the size and growth of the tumor. The clinical data of the patients were retrospectively analyzed. RESULTS: Based on the feasibility of this surgical approach, personalized skin incisions and bone flaps were designed for different lesions. Among the 60 patients, gross total resection was achieved in 53 cases (88.3%), for meningiomas 97.8% (46/47) and near-total resection in 7 cases (11.7%). In the survey of the patients' scale scores toward skin incision after operation, the "no pain" level was 90.0% (54/60) and 91.7% (55/60) for the level of "very satisfactory" of the aesthetic of the skin incision (as shown in Supplementary Digital Content, Table 2, http://links.lww.com/ SCS/D742). Three patients whose satisfaction with the aesthetic of the incision excelled scale 3, suggesting that they were not completely satisfied with the wound healing. No permanent skin incision discomfort was noted during follow-up. There were no surgical deaths. CONCLUSIONS: The SKA via forehead wrinkle incision is a flexible and feasible method for tumors near the midline of the anterior skull base and sellar region. However, this approach requires strict preoperative planning, which includes choosing appropriate tumors and applicable forehead wrinkles.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Estética Dental , Frente/cirugía , Humanos , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Estudios Retrospectivos , Base del Cráneo
17.
J Cell Mol Med ; 25(12): 5744-5752, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33991050

RESUMEN

Bioactive nanofibres play a useful role in increasing the efficiency of tissue engineering scaffolds. MicroRNAs (miRs) alone, and in combination with tissue engineering scaffolds, can be effective in treating bone fractures and osteoporosis by regulating many post-transcriptional cellular pathways. Herein, miR-181a/b-1 was incorporated in the electrospun poly (lactic-co-glycolic acid) (PLGA) nanofibres (PLGA-miR). After characterization scaffolds, the osteoinductive capacity of the nanofibres was investigated when adipose-derived mesenchymal stem cells (AT-MSCs) were cultured on the PLGA and PLGA-miR nanofibres. miR incorporating in the nanofibres has not any significant effect on the size and morphology of the nanofibres, but its biocompatibility was increased significantly compared to the empty nanofibres. Alkaline phosphatase (ALP) activity and calcium measures were evaluated as two important osteogenic markers, and the results revealed that the highest measures were observed in the AT-MSCs cultured on PLGA-miR nanofibres. Detected ALP activity and calcium measures in miR-transduced AT-MSCs cultured on TCPS were also significantly higher than AT-MSCs cultured on PLGA and TCPS groups. The highest expression levels of bone-related genes were observed in the AT-MSCs cultured on PLGA-miR nanofibres. This improvement in the osteogenic differentiation potential of the AT-MSCs was also confirmed by evaluating osteopontin protein in the cells cultured on PLGA-miR. It can be concluded that miR-181a/b-1 has a significant impact on the AT-MSC osteogenic differentiation, and this impact synergistically increased when incorporated in the PLGA nanofibres.


Asunto(s)
Diferenciación Celular , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Nanofibras/química , Osteogénesis , Poliésteres/química , Polietilenglicoles/química , Andamios del Tejido/química , Proliferación Celular , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/metabolismo , Ingeniería de Tejidos
18.
Small ; 17(30): e2007306, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34047461

RESUMEN

As a nanoscale renewable resource derived from lignocellulosic materials, cellulose nanocrystals (CNCs) have the features of high purity, high crystallinity, high aspect ratio, high Young's modulus, and large specific surface area. The most interesting trait is that they can form the entire films with bright structural colors through the evaporation-induced self-assembly (EISA) process under certain conditions. Structural color originates from micro-nano structure of CNCs matrixes via the interaction of nanoparticles with light, rather than the absorption and reflection of light from the pigment. CNCs are the new generation of photonic liquid crystal materials of choice due to their simple and convenient preparation processes, environmentally friendly fabrication approaches, and intrinsic chiral nematic structure. Therefore, understanding the forming mechanism of CNCs in nanoarchitectonics is crucial to multiple fields of physics, chemistry, materials science, and engineering application. Herein, a timely summary of the chiral photonic liquid crystal films derived from CNCs is systematically presented. The relationship of CNC, structural color, chiral nematic structure, film performance, and applications of chiral photonic liquid crystal films is discussed. The review article also summarizes the most recent achievements in the field of CNCs-based photonic functional materials along with the faced challenges.


Asunto(s)
Cristales Líquidos , Nanopartículas , Nanoestructuras , Celulosa , Óptica y Fotónica
19.
Bioorg Med Chem Lett ; 44: 128121, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34015506

RESUMEN

Oxidative stress and inflammation have been considered the main factors in the liver injury of clofibrate (CF). To obtain a novel antihyperlipidemic agent with antioxidant, anti-inflammation and hepatoprotection, the combination of sesamol and clofibric acid moieties was performed and achieved sesamol-clofibrate (CF-Sesamol). CF-Sesamol showed significant hypolipidemia effects in hyperlipidemia mice induced by Triton WR 1339, reducing TG by 38.8% (P < 0.01) and TC by 35.1% (P < 0.01). CF-Sesamol also displayed an alleviating effect on hepatotoxicity. The hepatic weight and hepatic coefficient were decreased. The amelioration of liver function was observed, such as aspartate and lactate transaminases (AST and ALT), alkaline phosphatase (ALP) and total proteins (TP) levels. Liver histopathological examination showed that hepatocyte necrosis, cytoplasmic loosening, nuclear degeneration and inflammatory cell infiltration reduced obviously by treatment with CF-Sesamol. Related molecular mechanisms on hepatoprotection showed that CF-Sesamol up-regulated Nrf2 and HO-1 expression and down-regulated p-NF-κB p65 expression in hepatic tissues. CF-Sesamol has significant antioxidant and anti-inflammatory effects. Plasma antioxidant enzymes such as SOD and CAT increased, anti-lipid peroxidation product MDA decreased. The expression of TNF-α and IL-6 inflammatory cytokines in liver was significantly lower than that in the CF group. The results indicated that CF-Sesamol exerted more potent antihyperlipidemic effects and definite hepatoprotective activity partly through the Nrf2/NF-κB-mediated signaling pathway.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antioxidantes/farmacología , Benzodioxoles/farmacología , Ácido Clofíbrico/farmacología , Hipolipemiantes/farmacología , Fenoles/farmacología , Sustancias Protectoras/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antioxidantes/síntesis química , Antioxidantes/química , Benzodioxoles/sangre , Benzodioxoles/química , Ácido Clofíbrico/sangre , Ácido Clofíbrico/química , Relación Dosis-Respuesta a Droga , Hiperlipidemias/inducido químicamente , Hiperlipidemias/tratamiento farmacológico , Hipolipemiantes/síntesis química , Hipolipemiantes/química , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Endogámicos , Simulación del Acoplamiento Molecular , Estructura Molecular , Estrés Oxidativo/efectos de los fármacos , Fenoles/sangre , Fenoles/química , Polietilenglicoles , Sustancias Protectoras/síntesis química , Sustancias Protectoras/química , Relación Estructura-Actividad
20.
Acta Pharmacol Sin ; 42(5): 832-842, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33824461

RESUMEN

Nanomedicine has attracted increasing attention and emerged as a safer and more effective modality in cancer treatment than conventional chemotherapy. In particular, the distinction of tumor microenvironment and normal tissues is often used in stimulus-responsive drug delivery systems for controlled release of therapeutic agents at target sites. In this study, we developed mesoporous silica nanoparticles (MSNs) coated with polyacrylic acid (PAA), and pH-sensitive lipid (PSL) for synergistic delivery and dual-pH-responsive sequential release of arsenic trioxide (ATO) and paclitaxel (PTX) (PL-PMSN-PTX/ATO). Tumor-targeting peptide F56 was used to modify MSNs, which conferred a target-specific delivery to cancer and endothelial cells under neoangiogenesis. PAA- and PSL-coated nanoparticles were characterized by TGA, TEM, FT-IR, and DLS. The drug-loaded nanoparticles displayed a dual-pH-responsive (pHe = 6.5, pHendo = 5.0) and sequential drug release profile. PTX within PSL was preferentially released at pH = 6.5, whereas ATO was mainly released at pH = 5.0. Drug-free carriers showed low cytotoxicity toward MCF-7 cells, but ATO and PTX co-delivered nanoparticles displayed a significant synergistic effect against MCF-7 cells, showing greater cell-cycle arrest in treated cells and more activation of apoptosis-related proteins than free drugs. Furthermore, the extracellular release of PTX caused an expansion of the interstitial space, allowing deeper penetration of the nanoparticles into the tumor mass through a tumor priming effect. As a result, FPL-PMSN-PTX/ATO exhibited improved in vivo circulation time, tumor-targeted delivery, and overall therapeutic efficacy.


Asunto(s)
Antineoplásicos/uso terapéutico , Trióxido de Arsénico/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Portadores de Fármacos/química , Nanopartículas/química , Paclitaxel/uso terapéutico , Resinas Acrílicas/química , Resinas Acrílicas/farmacocinética , Resinas Acrílicas/toxicidad , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Apoptosis/efectos de los fármacos , Trióxido de Arsénico/farmacocinética , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Cetrimonio/química , Cetrimonio/toxicidad , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidad , Liberación de Fármacos , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Células MCF-7 , Ratones Endogámicos ICR , Nanopartículas/toxicidad , Oligopéptidos/química , Oligopéptidos/farmacocinética , Oligopéptidos/toxicidad , Paclitaxel/química , Paclitaxel/farmacocinética , Porosidad , Dióxido de Silicio/química , Dióxido de Silicio/farmacocinética , Dióxido de Silicio/toxicidad , Ensayos Antitumor por Modelo de Xenoinjerto
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