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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(5): 682-690, 2023 May 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37539570

RESUMEN

OBJECTIVES: Primary trigeminal neuralgia (PTN) is a common cranial nerve disease in neurosurgery, which seriously endangers the physical and mental health of patients. Percutaneous balloon compression (PBC) has become an effective procedure for the treatment of PTN by blocking pain conduction through minimally invasive puncture. However, the recurrence of facial pain after PBC is still a major problem for PTN patients. Intraoperative balloon shape, pressure and compression time can affect the prognosis of patients with PBC after surgery. The foramen ovale size has an effect on the balloon pressure in Meckel's lumen. This study aims to analyse the predictive value of foramen ovale size for postoperative pain recurrence of PBC by exploring the relationship between foramen ovale size and postoperative pain recurrence of PBC. METHODS: A retrospectively analysis was conducted on the clinical data of 60 patients with PTN who were treated with PBC in Department of Neurosurgery, Affiliated Hospital of Chengde Medical College from November 2018 to December 2021. We followed-up and recorded the Barrow Neurological Institute (BNI) pain score at 1, 3, 6 and 12 months after operation. According to the BNI pain score at 12 months after surgery, the patients were divided into a cure group (BNI pain score I to Ⅱ) and a recurrence group (BNI pain score Ⅲ to Ⅴ). The long diameter, transverse diameter and area of foramen ovale on the affected side and the healthy side of the 2 groups were measured. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used for analysis the relationship between the recurrence of pain and the long diameter, transverse diameter, area of foramen ovale on the affected side, and aspect ratio, transverse diameter ratio, area ratio of foramen ovale on the affected side to healthy side in the 2 groups. RESULTS: At the end of 12 months of follow-up, 50 (83.3%) patients had pain relief (the cured group), 10 (16.7%) patients had different degrees of pain recurrence (the recurrence group), and the total effective rate was 83.3%. There were no significant differences in preoperative baseline data between the 2 groups (all P>0.05). The long diameter of foramen ovale on the affected side, the long diameter ratio and area ratio of foramen ovale on the affected/healthy side in the cured group were significantly higher than those in the recurrence group (all P<0.05), and there were no significant differences in the transverse diameter and area of foramen ovale on the affected side and the transverse diameter ratio of foramen ovale on the affected/healthy side between the 2 groups (all P>0.05). The ROC curve analysis showed that the AUC of the long diameter of foramen ovale on the affected side was 0.290 (95% CI 0.131 to 0.449, P=0.073), and the AUC of aspect ratio of foramen ovale on the affected side to healthy side was 0.792 (95% CI 0.628 to 0.956, P=0.004). The AUC of area ratio of foramen ovale on the affected side to healthy side was 0.766 (95% CI 0.591 to 0.941, P=0.008), indicating that aspect ratio and area ratio of foramen ovale on the affected side to healthy side had a good predictive effect on postoperative pain recurrence of PBC. When aspect ratio of foramen ovale on the affected side to healthy side was less than 0.886 3 or area ratio of foramen ovale on the affected side to healthy side was less than 0.869 4, postoperative pain recurrence was common. CONCLUSIONS: Accurate evaluation of the foramen ovale size of skull base before operation is of great significance in predicting pain recurrence after PBC.


Asunto(s)
Foramen Oval , Neuralgia del Trigémino , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Neuralgia del Trigémino/etiología , Neuralgia del Trigémino/cirugía , Dolor Postoperatorio/etiología , Recurrencia
2.
Small ; 18(5): e2101518, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34658130

RESUMEN

Conductive hydrogels can be prepared by incorporating various conductive materials into polymeric network hydrogels. In recent years, conductive hydrogels have been developed and applied in the field of strain sensors owing to their unique properties, such as electrical conductivity, mechanical properties, self-healing, and anti-freezing properties. These remarkable properties allow conductive hydrogel-based strain sensors to show excellent performance for identifying external stimuli and detecting human body movement, even at subzero temperatures. This review summarizes the properties of conductive hydrogels and their application in the fabrication of strain sensors working in different modes. Finally, a brief prospectus for the development of conductive hydrogels in the future is provided.


Asunto(s)
Hidrogeles , Dispositivos Electrónicos Vestibles , Conductividad Eléctrica , Humanos , Movimiento , Polímeros
3.
Biomacromolecules ; 23(3): 829-838, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35191679

RESUMEN

Thehighly efficient utilization of lignin is of great importance for the development of the biorefinery industry. Herein, a novel "core-shell" lignin nanoparticle (LNP) with a diameter of around 135 nm was prepared, after the lignin was isolated from the effluent of formic acid fractionation via dialysis. In an attempt to endow composite materials with vital functionalities, the LNP was added to the starch film and the starch/polyvinyl alcohol (PVA) or starch/polyethylene oxide (PEO) composite film. The results showed that the hydrophobicity performance of the synthesized films was enhanced significantly. Specifically, the dynamic water contact angle value of the starch/PVA composite film with 1% (wt) addition of LNPs could be maintained as high as 122° for 180 s; the starch/PEO composite film also achieved an excellent water contact angle above 120°. The addition of LNPs promoted the formation of some rough structures on the film surface, as shown by the scanning electron microscopy images, which could repel the water molecules efficiently and are closely related to the enhanced hydrophobicity of the starch film. What is more, the as-prepared LNP conferred strengthened thermal stability and ultraviolet blocking properties on the starch composite film. The structural combination of the polymer film with LNPs holds the promise for providing advanced functionalities to the composite material with wide applications.


Asunto(s)
Lignina , Nanopartículas , Interacciones Hidrofóbicas e Hidrofílicas , Lignina/química , Nanopartículas/química , Alcohol Polivinílico/química , Almidón/química , Resistencia a la Tracción , Agua/química
4.
Biomacromolecules ; 22(11): 4501-4509, 2021 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-34601873

RESUMEN

Biografting is a promising and ecofriendly approach to meet various application requirements of products. Herein, a popular green enzyme, laccase, was adopted to graft a hydrophobic phenolic compound (lauryl gallate, LG) onto chitosan (CTS). The resultant chitosan derivate (Lac/LG-CTS) was systematically analyzed by Fourier transform infrared (FTIR), grafting efficiency, scanning probe microscopy (SPM), and X-ray diffraction (XRD). This grafting technique produced a multifunctional chitosan copolymer with remarkably enhanced antioxidant property, hydrophobicity, and moisture barrier property. Furthermore, the swelling capacity and acid solubility of the copolymer film decreased significantly, although the tensile strength and elongation were slightly weakened as compared to those of native chitosan. These results suggest that the Lac/LG-CTS holds great potential as a food-packaging material, preservative agent, or edible coating material.


Asunto(s)
Quitosano , Antioxidantes , Catálisis , Ácido Gálico/análogos & derivados , Interacciones Hidrofóbicas e Hidrofílicas , Lacasa
5.
Anal Biochem ; 607: 113835, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32739347

RESUMEN

A reversible fluorescence probe for acetylcholinesterase activity detection was developed based on water soluble perylene derivative, N,N'-di(2-aspartic acid)-perylene-3,4,9,10-tetracarboxylic diimide (PASP). Based on the photo-induced electron transfer (PET), PASP fluorescence in aqueous is quenched after combining with copper ions (Cu2+). Acetylcholinesterase (AChE) is well known to catalyze the hydrolysis of acetylcholine (ATCh) to produce thiocholine, whose affinity is strong enough to capture Cu2+ by thiol (-SH) group from the complex PASP-Cu, resulting in the fluorescence signal of PASP recovers up to 90%. This optical switch is highly sensitive depended on the coordination and dissociation between PASP and Cu2+. We proposed its application for AChE activity detection, as well as its inhibitor screening. According to the change of fluorescence intensity, quantifying the detection limit of AChE was 1.78 mU·mL-1. Classical inhibitors, tacrine and organophosphate pesticide diazinon, were further evaluated for drug screening. The IC50 value of tacrine was calculated to be 0.43 µM, and the detection limit of diazinon was 0.22 µM. Both of these performances were much better than previous results, revealing our probe is sensitive and reversible for screening applications.


Asunto(s)
Acetilcolinesterasa/análisis , Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/metabolismo , Diazinón/química , Diazinón/metabolismo , Colorantes Fluorescentes/química , Perileno/química , Tacrina/química , Tacrina/metabolismo , Unión Competitiva , Inhibidores de la Colinesterasa/farmacología , Diazinón/farmacología , Evaluación Preclínica de Medicamentos , Activación Enzimática/efectos de los fármacos , Espectrometría de Fluorescencia , Especificidad por Sustrato , Tacrina/farmacología
6.
Biochim Biophys Acta Bioenerg ; 1859(5): 366-373, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29501404

RESUMEN

The NADH:ubiquinone oxidoreductase (complex I) is the first enzyme of the respiratory chain and the entry point for most electrons. Generally, the bacterial complex I consists of 14 core subunits, homologues of which are also found in complex I of mitochondria. In complex I preparations from the hyperthermophilic bacterium Aquifex aeolicus we have identified 20 partially homologous subunits by combining MALDI-TOF and LILBID mass spectrometry methods. The subunits could be assigned to two different complex I isoforms, named NQOR1 and NQOR2. NQOR1 consists of subunits NuoA2, NuoB, NuoD2, NuoE, NuoF, NuoG, NuoI1, NuoH1, NuoJ1, NuoK1, NuoL1, NuoM1 and NuoN1, with an entire mass of 504.17 kDa. NQOR2 comprises subunits NuoA1, NuoB, NuoD1, NuoE, NuoF, NuoG, NuoH2, NuoI2, NuoJ1, NuoK1, NuoL2, NuoM2 and NuoN2, with a total mass of 523.99 kDa. Three Fe-S clusters could be identified by EPR spectroscopy in a preparation containing predominantly NQOR1. These were tentatively assigned to a binuclear center N1, and two tetranuclear centers, N2 and N4. The redox midpoint potentials of N1 and N2 are -273 mV and -184 mV, respectively. Specific activity assays indicated that NQOR1 from cells grown under low concentrations of oxygen was the more active form. Increasing the concentration of oxygen in the bacterial cultures induced formation of NQOR2 showing the lower specific activity.


Asunto(s)
Bacterias/enzimología , Proteínas Bacterianas/sangre , Complejo I de Transporte de Electrón/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
7.
Reprod Biol Endocrinol ; 16(1): 63, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29976200

RESUMEN

BACKGROUND: To examine the effects of IVF, ICSI and FET, as well as in vitro culture, on the safety of offspring, this study was conducted from the perspective of genetic imprinting to investigate whether assisted reproductive technology would influence the parental and maternal imprinting genes. METHODS: Eighteen foetuses were collected from multifoetal reduction and divided into 6 groups: multifoetal reduction after IVF fresh transferred D3 embryos (n = 3), multifoetal reduction after IVF frozen transferred D3 embryos (n = 3), multifoetal reduction after IVF frozen transferred D5 embryos (n = 3), multifoetal reduction after ICSI fresh transferred D3 embryos (n = 3), multifoetal reduction after ICSI frozen transferred D3 embryos (n = 3), and multifoetal reduction after controlled ovarian hyperstimulation (COH) (n = 3). The imprinted genes H19, IGF2 and SNRPN were selected for analysis. The expression and DNA methylation at some CpG sites of H19, IGF2, and SNRPN were examined using real-time quantitative polymerase chain reaction (PCR) and pyrosequencing. RESULTS: There were no significant differences in the mRNA expression levels among the groups. The mean percentage of H19 methylation (eight CpG sites), IGF2 methylation (five CpG sites) and SNRPN methylation (nine CpG sites) did not differ significantly. CONCLUSIONS: The results suggest that ARTs after controlled ovarian stimulation (IVF, ICSI, cryopreservation and duration of in vitro culture) may not increase the risk of abnormal expression and DNA methylation at some CpG sites of H19, IGF2 and SNRPN in foetuses. Further study with strict design, expanded sample size and CpG sites is essential.


Asunto(s)
Islas de CpG/genética , Metilación de ADN , Inducción de la Ovulación/efectos adversos , Técnicas Reproductivas Asistidas/efectos adversos , Criopreservación , Feto/metabolismo , Regulación del Desarrollo de la Expresión Génica , Impresión Genómica/genética , Humanos , Factor II del Crecimiento Similar a la Insulina/química , Factor II del Crecimiento Similar a la Insulina/genética , Proyectos Piloto , ARN Largo no Codificante/química , ARN Largo no Codificante/genética , Proteínas Nucleares snRNP/química , Proteínas Nucleares snRNP/genética
8.
Langmuir ; 31(35): 9537-45, 2015 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-26287510

RESUMEN

Recently, carbon dots (CDs) have drawn much attention as evidenced by their incorporation into many branches of science and engineering. Herein, a further unique application is elucidated: CDs that are synthesized by the hydrothermal treatment of gelatin for a dual functionality as expressed in costabilization of particle-based emulsions and their concomitant role as fluorescent probes. CDs either with or without gelatin matrixes induce the aggregation of Laponite particles. The introduction of CDs thus enhanced the stability of Laponite-stabilized emulsions and promoted the formation of multiple emulsions and emulsions with fine and uniform droplets when the CD-to-Laponite mass ratio was less than 45% and exceeded 60%, respectively. However, CDs without gelatin matrixes show slightly higher efficiency than CDs within gelatin matrixes for the costabilization of emulsions. CDs also costabilized emulsions with Laponite to allow the distribution of Laponite particles to be traced and the emulsion profiled under UV.

9.
Wei Sheng Wu Xue Bao ; 54(1): 89-96, 2014 Jan 04.
Artículo en Zh | MEDLINE | ID: mdl-24783858

RESUMEN

OBJECTIVE: To construct an expression vector for alkaliphilic Bacillus sp. N16-5. METHODS: Bacillus subtilis expression vector pHCMC04 was used as a backbone. Its xylose-inducible promoter cassette was replaced by the constitutive promoters P43 (from B. subtilis) and P(EF) (from Bacillus sp. N165), separately, resulting in two expression vectors pABN165P43 and pABN165P(EF). Green fluorescent protein gene gfp was linked to the two vectors as a reporter gene. Fluorescence microscope and multifunctional fluorescent reader were used to test the expression efficiency of the system. RESULTS: Green fluorescence was visualized in Bacillus sp. N16-5 with pABN165P(EF)-gfp or pABN165P43-gfp. Quantitative data analysis revealed that fluorescence was first detected around the 7th hour. The fluorescence intensity increased rapidly from the 7th hour to the 12th hour and reached the maximum at about the 12th hour. CONCLUSION: Two expression vectors for Bacillus sp. N16-5 have been constructed, allowing expression of exogenous protein in alkaliphilic Bacillus sp. N165.


Asunto(s)
Bacillus/genética , Ingeniería Genética/métodos , Vectores Genéticos/genética , Expresión Génica , Proteínas Fluorescentes Verdes/genética , Concentración de Iones de Hidrógeno , Reacción en Cadena de la Polimerasa
10.
Int J Biol Macromol ; 268(Pt 2): 131953, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685536

RESUMEN

Solar desalination is an effective solution to address the global water scarcity issue. However, biofouling poses a significant challenge for solar evaporators due to the presence of bacteria in seawater. In this study, an anti-biofouling evaporator was constructed using the synergistic antibacterial effect of lignin and silver nanoparticles (AgNPs). The AgNPs were easily synthesized using lignin as reductant under mild reaction conditions. Subsequently, the Lignin-AgNPs solution was integrated into polyacrylamide hydrogel (PAAm) without any purification steps, resulting in the formation of Lignin/AgNPs-PAAm (LAg-PAAm). Under the combined action of AgNPs and the hydroquinone groups present in oxidized lignin, LAg-PAAm achieved over 99 % disinfection efficiency within 1 h, effectively preventing biofilm formation in pore channels of solar evaporators. The anti-biofouling solar evaporator demonstrated an evaporation rate of 1.85 kg m-2 h-1 under 1 sun irradiation, and maintained stable performance for >30 days due to its high efficient bactericidal effect. Furthermore, it also exhibited exceptional salt-rejection capability attributed to its superior hydrophilicity.


Asunto(s)
Antibacterianos , Incrustaciones Biológicas , Lignina , Nanopartículas del Metal , Plata , Lignina/química , Lignina/farmacología , Plata/química , Plata/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Incrustaciones Biológicas/prevención & control , Nanopartículas del Metal/química , Luz Solar , Resinas Acrílicas/química , Biopelículas/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Pruebas de Sensibilidad Microbiana
11.
Int J Biol Macromol ; 254(Pt 3): 127958, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37951428

RESUMEN

Flexible wearable devices are garnering significant interest, with conductive hydrogels emerging as a particularly notable category. While many of these hydrogels offer impressive conductivity, they often lack the innate ability to adhere autonomously to human skin. The ideal hydrogel should possess both superior adhesion properties and a wide responsive range. This study introduces a novel double-network conductive hydrogel, synthesized from lignosulfonate sodium and ionic liquid using a one-pot method. The gel's mechanical robustness (fracture elongation of ∼3500 % and tensile strength of ∼130 kPa) and exceptional conductivity sensing performance arise from the synergistic effects of electrostatic interactions, dynamic hydrogen bonding, and a three-dimensional network structure. Additionally, the phenolic hydroxyl and sulfonic groups from lignosulfonate sodium imbue the hydrogel with adhesive qualities, allowing it to easily bond with varied material surfaces. This hydrogel excels in human physiological signal detection and wireless monitoring, demonstrating a rapid response time (149 ms) and high sensitivity (a maximum gauge factor of 10.9 for strains between 400 and 600 %). Given these properties, the flexible, self-adhesive, and conductive hydrogel showcases immense promise for future applications in wearable devices and wireless transmission sensing.


Asunto(s)
Líquidos Iónicos , Humanos , Exactitud de los Datos , Conductividad Eléctrica , Hidrogeles
12.
Int J Biol Macromol ; 274(Pt 1): 133398, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38917925

RESUMEN

Sodium alginate (SA) is widely used in the food, biomedical, and chemical industries due to its biocompatibility, biodegradability, and excellent film-forming properties. This article introduces a simple method for preparing uniform alginate-based packaging materials with exceptional properties for fruit preservation. The alginate was uniformly crosslinked by gradually releasing calcium ions triggered by the sustained hydrolysis of gluconolactone (GDL). A cinnamaldehyde (CA) emulsion, stabilized by xanthan without the use of traditional surfactants, was tightly incorporated into the alginate film to enhance its antimicrobial, antioxidant, and UV shielding properties. The alginate-based film effectively blocked ultraviolet rays in the range of 400-200 nm, while allowing for a visible light transmittance of up to 70 %. Additionally, it showed an increased water contact angle and decreased water vapor permeability. The alginate-based film was also employed in the preparation of coated paper through the commonly used coating process in the papermaking industry. The alginate-based material displayed excellent antioxidant properties and antimicrobial activity against Escherichia coli, Staphylococcus aureus and Botrytis cinerea, successfully extending the shelf life of strawberries to 7 days at room temperature. This low-cost and facile method has the potential to drive advancements in the food and biomedical fields by tightly incorporating active oil onto a wide range of biomacromolecule substrates.

13.
Int J Biol Macromol ; 271(Pt 1): 132494, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38788874

RESUMEN

The synthesis of liquid metal-infused hydrogels, typically constituted by polyacrylamide networks crosslinked through covalent bonds, often encounters a conundrum: they exhibit restricted extensibility and a diminished capacity for self-repair, owing to the inherently irreversible nature of the covalent linkages. This study introduces a hydrophobically associated hydrogel embedding gallium (Ga)-droplets, realized through the in situ free radical copolymerization of hydrophobic hexadecyl methacrylate (HMA) and hydrophilic acrylamide (AM) in a milieu containing xanthan gum (XG) and PEDOT:PSS, which co-stabilizes the Ga-droplets. The Ga-droplets, synergistically functioning as conductive agents alongside PEDOT:PSS, also expedite the hydrogel's formation. The resultant XG/PEDOT:PSS-Ga-P(AM-HMA) hydrogel is distinguished by its remarkable extensibility (2950 %), exceptional toughness (3.28 MJ/m3), superior adherence to hydrophobic, smooth substrates, and an innate ability for hydrophobic-driven self-healing. As a strain sensing medium, this hydrogel-based sensor exhibits heightened sensitivity (gauge factor = 12.66), low detection threshold (0.1 %), and robust durability (>500 cycles). Furthermore, the inclusion of glycerol endows the XG/PEDOT:PSS-Ga-P(AM-HMA) hydrogel with anti-freezing properties without compromising its mechanical integrity and sensing acumen. This sensor adeptly captures a spectrum of human movements, from the nuanced radial pulse to extensive joint articulations. This research heralds a novel approach for fabricating multifaceted PAM-based hydrogels with toughness and superior sensing capabilities.


Asunto(s)
Hidrogeles , Interacciones Hidrofóbicas e Hidrofílicas , Polímeros , Polisacáridos Bacterianos , Hidrogeles/química , Polisacáridos Bacterianos/química , Polímeros/química , Poliestirenos/química , Galio/química , Metales/química , Compuestos Bicíclicos Heterocíclicos con Puentes
14.
Carbohydr Polym ; 326: 121621, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142077

RESUMEN

Conductive hydrogels have received increasing attention in the field of wearable electronics, but they also face many challenges such as temperature tolerance, biocompatibility, and stability of mechanical properties. In this paper, a double network hydrogel of MXene/TEMPO bacterial cellulose (TOBC) system is proposed. Through solvent replacement, the hydrogel exhibits wide temperature tolerance (-20-60 °C) and stable mechanical properties. A large number of hydrogen bonds, MXene/TOBC dynamic three-dimensional network system, and micellar interactions endow the hydrogel with excellent mechanical properties (elongation at break ~2800 %, strength at break ~420 kPa) and self-healing ability. The introduction of tannic acid prevents the oxidation of MXene and the loss of electrical properties of the hydrogel. In addition, the sensor can also quickly (74 ms) and sensitive (gauge factor = 15.65) wirelessly monitor human motion, and the biocompatibility can well avoid the stimulation when it comes into contact with the human body. This series of research work reveals the fabrication of MXene-like flexible wearable electronic devices based on self-healing, good cell compatibility, high sensitivity, wide temperature tolerance and durability, which can be used in smart wearable, wireless monitoring, human-machine Interaction and other aspects show great application potential.


Asunto(s)
Celulosa , Hidrogeles , Humanos , Conductividad Eléctrica
15.
Int J Biol Macromol ; 260(Pt 1): 129272, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38211925

RESUMEN

Conductive hydrogels, especially polysaccharide-based ionic conductive hydrogels, have received increasing interest in the field of wearable sensors due to their similarity to human skin. Nevertheless, it is still a challenging task to simultaneously prepare a self-healed and adhesive conductive hydrogel with good toughness, temperature tolerance and high sensing performance, especially with high sensitivity and a low detection limit. Herein, we developed a new strategy to improve the toughness and sensing performance of a multifunctional conductive hydrogel by simultaneously using dissolved chitosan (CS) and solid chitosan nanofibers (CSFs) to induce the formation of hierarchical polymeric networks in the hydrogel. The tensile strength and elongation at break of the hydrogel could be improved from 70.3 kPa and 1005 % to 173.9 kPa and 1477 %, respectively, simply by introducing CSFs to the hydrogel, and its self-healing, adhesive and antibacterial properties were effectively retained. When serving as a resistive sensing material, the introduction of CSFs increased the gauge factor of the hydrogel-based strain sensor from 8.25 to 14.27. Moreover, the hydrogel-based strain sensor showed an ultralow detection limit of 0.2 %, excellent durability and stability (1000 cycles) and could be used to detect various human activities. In addition, the hydrogel prepared by using a water-glycerol binary solvent system showed temperature-tolerant performance and possessed adequate sensitivity when serving as a resistive sensing material. Therefore, this work provides a new way to prepare multifunctional conductive hydrogels with good toughness, sensing performance and temperature tolerance to expand the application range of hydrogel-based strain sensors.


Asunto(s)
Quitosano , Nanofibras , Materiales Inteligentes , Humanos , Hidrogeles , Antibacterianos , Conductividad Eléctrica , Iones
16.
Int J Biol Macromol ; 259(Pt 1): 129225, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38184053

RESUMEN

Liquid metal (LM) microdroplets have garnered significant interest as conductive materials for initiating free radical polymerization in the development of conductive hydrogels suited for strain sensors. However, crafting multi-functional conductive hydrogels that boast both high stretchability and superior sensing capabilities remains as a challenge. In this study, we have successfully synthesized LM-based conductive hydrogels characterized by remarkable stretchability and sensing performance employing acrylic acid (AA) to evenly distribute chitosan nanofibers (CSFs) and to subsequently catalyze the free radical polymerization of AA. The resultant polymer network was crosslinked within situ polyacrylic acid (PAA), facilitated by Ga3+ in conjunction with guar gum (GG)-stabilized Ga droplets. The strategic interplay between the rigid, and protonated CSFs and the pliable PAA matrix, coupled with the ionic crosslinking of Ga3+, endows the resulting GG-Ga-CSF-PAA hydrogel with high stretchability (3700 %), ultrafast self-healing, robust moldability, and strong adhesiveness. When deployed as a strain sensing material, this hydrogel exhibits a high gauge factor (38.8), a minimal detection threshold, enduring durability, and a broad operational range. This versatility enables the hydrogel-based strain sensor to monitor a wide spectrum of human motions. Remarkably, the hydrogel maintains its stretchability and sensing efficacy under extreme temperatures after a simple glycerol solution treatment.


Asunto(s)
Acrilatos , Quitosano , Nanofibras , Humanos , Hidrogeles , Conductividad Eléctrica , Radicales Libres
17.
J Ethnopharmacol ; 328: 117957, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38493904

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: As reported in the Ancient Chinese Medicinal Books, Ginkgo biloba L. fruit has been used as a traditional Chinese medicine for the treatment asthma and cough or as a disinfectant. Our previous study demonstrated that G. biloba exocarp extract (GBEE), an extract of a traditional Chinese herb, inhibits the formation of methicillin-resistant Staphylococcus aureus (MRSA) biofilms. However, GBEE is a crude extract that contains many components, and the underlying mechanisms of purified GBEE fractions extracted with solvents of different polarities are unknown. AIM OF THE STUDY: This study aimed to investigate the different components in GBEE fractions extracted with solvents of different polarities and their antibacterial effects and mechanisms against MRSA and Staphylococcus haemolyticus biofilms both in vitro and in vivo. METHODS: The components in different fractions were detected by high-performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS). Microbroth dilution assays and time growth curves were used to determine the antibacterial effects of the fractions on 15 clinical bacterial isolates. Crystal violet staining, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to identify the fractions that affected bacterial biofilm formation. The potential MRSA targets of the GBEE fraction obtained with petroleum ether (PE), denoted GBEE-PE, were screened by transcriptome sequencing, and the gene expression profile was verified by quantitative polymerase chain reaction (qPCR). RESULTS: HPLC-HRMS analysis revealed that the four GBEE fractions (extracted with petroleum ether, ethyl acetate, n-butanol, and water) contained different ginkgo components, and the antibacterial effects decreased as the polarity of the extraction solvent increased. The antibacterial activity of GBEE-PE was greater than that of the GBEE fraction extracted with ethyl acetate (EA). GBEE-PE improved H. illucens survival and reduced MRSA colonization in model mouse organs. Crystal violet staining and SEM and TEM analyses revealed that GBEE-PE inhibited MRSA and S. haemolyticus biofilm formation. Transcriptional analysis revealed that GBEE-PE inhibits MRSA biofilms by altering ion transport, cell wall metabolism and virulence-related gene expression. In addition, the LO2 cell viability and H. illucens toxicity assay data showed that GBEE-PE at 20 mg/kg was nontoxic. CONCLUSION: The GBEE fractions contained different components, and their antibacterial effects decreased with increases in the polarity of the extraction solvent. GBEE-PE limited MRSA growth and biofilm formation by affecting ion transport, cell wall synthesis, and virulence-related pathways. This research provides a more detailed overview of the mechanism by which GBEE-PE inhibits MRSA both in vitro and in vivo and suggests that GBEE-PE is a new prospective antimicrobial with the potential to be used in MRSA therapeutics in the future.


Asunto(s)
Acetatos , Alcanos , Staphylococcus aureus Resistente a Meticilina , Animales , Ratones , Ginkgo biloba/química , Virulencia , Violeta de Genciana/farmacología , Estudios Prospectivos , Extractos Vegetales/farmacología , Solventes/química , Antibacterianos/farmacología , Biopelículas , Pruebas de Sensibilidad Microbiana
18.
Int J Biol Macromol ; 274(Pt 2): 133431, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38936573

RESUMEN

High internal phase Pickering emulsions (HIPEs) constitute a significant research domain within colloid interface chemistry, addressing the demand for robust emulsion systems across various applications. An innovative nanoparticle, synthesized from a cyclodextrin metal-organic framework encapsulated with a composite of resveratrol and soy isolate protein (RCS), was employed to fortify a high internal phase emulsion. The emulsion's three-dimensional printing capabilities, alongside the encapsulated delivery efficacy for ß-carotene, were thoroughly examined. Cyclodextrin metal-organic frameworks (CD-MOFs), facilitated by cellulose nanofibrils, were synthesized to yield particles at the nanoscale, maintaining a remarkable 97.67 % cellular viability at an elevated concentration of 1000 µg/ml. The RCS nanoparticles demonstrated thermal stability and antioxidant capacities surpassing those of CD-MOF. The integration of soybean isolate protein augmented both the hydrophobicity (from 21.95 ± 0.64° to 59.15 ± 0.78°) and the interfacial tension (from 14.36 ± 0.46 mN/m to 5.34 ± 0.81 mN/m) of the CD-MOF encapsulated with resveratrol, thereby enhancing the RCS nanoparticles' adsorption at the oil-water interface with greater stability. The durability of the RCS-stabilized high internal phase emulsions was contingent upon the RCS concentration. Emulsions stabilized with 5 wt%-RCS exhibited optimal physical and chemical robustness, demonstrating superior performance in emulsion 3D printing and ß-carotene encapsulation delivery. This investigation furnishes a novel perspective on the amalgamation of food customization and precision nutrition.

19.
Front Microbiol ; 15: 1358752, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38873147

RESUMEN

Candida albicans (C. albicans), a microbe commonly isolated from Candida vaginitis patients with vaginal tract infections, transforms from yeast to hyphae and produces many toxins, adhesins, and invasins, as well as C. albicans biofilms resistant to antifungal antibiotic treatment. Effective agents against this pathogen are urgently needed. Antimicrobial peptides (AMPs) have been used to cure inflammation and infectious diseases. In this study, we isolated whole housefly larvae insect SVWC peptide 1 (WHIS1), a novel insect single von Willebrand factor C-domain protein (SVWC) peptide from whole housefly larvae. The expression pattern of WHIS1 showed a response to the stimulation of C. albicans. In contrast to other SVWC members, which function as antiviral peptides, interferon (IFN) analogs or pathogen recognition receptors (PRRs), which are the prokaryotically expressed MdWHIS1 protein, inhibit the growth of C. albicans. Eukaryotic heterologous expression of WHIS1 inhibited C. albicans invasion into A549 and HeLa cells. The heterologous expression of WHIS1 clearly inhibited hyphal formation both extracellularly and intracellularly. Furthermore, the mechanism of WHIS1 has demonstrated that it downregulates all key hyphal formation factors (ALS1, ALS3, ALS5, ECE1, HWP1, HGC1, EFG1, and ZAP1) both extracellularly and intracellularly. These data showed that heterologously expressed WHIS1 inhibits C. albicans invasion into epithelial cells by affecting hyphal formation and adhesion factor-related gene expression. These findings provide new potential drug candidates for treating C. albicans infection.

20.
Int J Biol Macromol ; 242(Pt 1): 124711, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37148947

RESUMEN

Polyaniline is widely used in the field of electrochemistry due to its excellent electrical conductivity. However, its effectiveness and mechanism of enhancing adsorption property are unclear. Herein, chitosan/polyaniline nanofibrous composite membranes with average diameter ranging from 200 to 300 nm were fabricated by electrospinning technology. The as-prepared nanofibrous membranes exhibited significantly improved adsorption capacity of 814.9 mg/g and 618.0 mg/g towards acid blue 113 and reactive orange dyes, which were 121.8 % and 99.4 % higher than that of pure chitosan membrane. The doped polyaniline promoted the dye transfer rate and capacity due to the enhanced conductivity of the composite membrane. Kinetic data showed that chemisorption was the rate-limiting step, and thermodynamic data indicated the adsorption of the two anionic dyes was spontaneous monolayer adsorption. This study provides a feasible strategy to introduce conductive polymer into adsorbent to construct high performance adsorbents for wastewater treatment.


Asunto(s)
Quitosano , Nanofibras , Contaminantes Químicos del Agua , Quitosano/química , Colorantes/química , Adsorción , Nanofibras/química , Cinética , Conductividad Eléctrica , Contaminantes Químicos del Agua/química
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