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1.
Animals (Basel) ; 14(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38929409

RESUMO

Rotavirus is a major causative agent of diarrhoea in children, infants, and young animals around the world. The associated zoonotic risk necessitates the serious consideration of the complete genetic information of rotavirus. A segmented genome makes rotavirus prone to rearrangement and the formation of a new viral strain. Monitoring the molecular epidemiology of rotavirus is essential for its prevention and control. The quantitative RT-PCR targeting the NSP5 gene was used to detect rotavirus group A (RVA) in pig faecal samples, and two pairs of universal primers and protocols were used for amplifying the G and P genotype. The genotyping and phylogenetic analysis of 11 genes were performed by RT-PCR and a basic bioinformatics method. A unique G4P[6] rotavirus strain, designated S2CF (RVA/Pig-tc/CHN/S2CF/2023/G4P[6]), was identified in one faecal sample from a piglet with severe diarrhoea in Guangdong, China. Whole genome sequencing and analysis suggested that the 11 segments of the S2CF strain showed a unique Wa-like genotype constellation and a typical porcine RVA genomic configuration of G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1. Notably, 4 of the 11 gene segments (VP4, VP6, VP2, and NSP5) clustered consistently with human-like RVAs, suggesting independent human-to-porcine interspecies transmission. Moreover, a unique 344-nt duplicated sequence was identified for the first time in the untranslated region of NSP5. This study further reveals the genetic diversity and potential inter-species transmission of porcine rotavirus.

2.
Carbohydr Polym ; 255: 117495, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436253

RESUMO

Poly(aminobenzeneboronic acid)-cellulose nanocrystals (PABA@CNCs) mediated self-healing and shape memory hydrogels are reported for the first time. PABA@CNCs are designed as efficient crosslinker, light-to-heat generator and strengthening agent in hydrogel. CNCs within dual crosslinking networks characterized by physical microcrystallization and dynamic covalent boronic bonds endow robust mechanical strength (tensile stress of 224 kPa) whose tensile stresses are 18 times higher than the single component PVA hydrogel. Reversible microcrystallization-induced fast and efficient self-healing behavior (healing efficiency ≥96.0 %) is easily obtained by exposing the hydrogel to a near-infrared (NIR) laser within 2 min. PABA@CNCs, a superior light-to-heat generator, is responsible for above melting-crystallization process. Meanwhile, the shape memory property with a shape fixity and recovery ratio of 88.9 % and 81.9 % are validated under fast pH-responsive boronic bonds between PABA@CNCs and PVA. In addition, the as-prepared hydrogel shows excellent affinity to a L929 cell, whose cell viability is higher than 95 %.

3.
Int J Biol Macromol ; 170: 272-283, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33359808

RESUMO

Electro-conductive hydrogel (ECH) with self-healing, shape memory and biocompatible properties is highly urgent for wearable strain sensors to prolonging their lifespan, endowing programmable shape control property, and improving affinity to skin during service. However, most of synthetic polymer-based ECH usually involve potential toxicity, long healing and shape drive time. Herein, a fast healable and shape memory ECH with excellent biocompatibility is reported for the first time by incorporating cellulose nanocrystals grafted phenylboronic acid (CNCs-ABA) and multiwalled carbon nanotubes (MWCNTs) into polyvinyl alcohol (PVA). CNCs-ABA is designed as dispersant and crosslinker in hydrogel. pH-induced dynamic borate bonds give hydrogel excellent shape recovery and fixity ratio of 82.1% and 78.2%, respectively. Meanwhile, 97.1% healing efficiency is obtained within 2 min depending on remarkable photothermal effect of MWCNTs and reversible microcrystallization. Double crosslinking networks endow excellent mechanical properties to hydrogel, whose tensile strength, strain and elastic modulus reach 227.0 kPa, 395.0% and 9.0 kPa, respectively. Furthermore, the synergistic effect of MWCNTs and NaOH enhance the conductivity of hydrogel with value of 3.8×10-2 S/m. In addition, the hydrogel can act as strain sensor for detecting human motion with superior biocompatibility and fast resistance response to applied strain, which is suitable for human health management.


Assuntos
Celulose/farmacologia , Nanopartículas/química , Cicatrização/efeitos dos fármacos , Materiais Biocompatíveis/química , Condutividade Elétrica , Hidrogéis/química , Nanotubos de Carbono/química , Polímeros/química , Álcool de Polivinil/química , Pele/efeitos dos fármacos , Resistência à Tração , Dispositivos Eletrônicos Vestíveis/tendências
4.
Int J Biol Macromol ; 163: 788-800, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32652157

RESUMO

Gold nanoparticles (AuNPs) within 10 nm prepared and stabilized by environmentally friendly reducing and supporting agents are highly desired to obtain excellent catalytic properties for organic transformation. In this paper, a rapid and mild strategy for synthesizing ultra-fine AuNPs is reported by using dialdehyde cellulose nanocrystals (DACNCs) as both efficient reductant, dispersant and template for the first time. DACNCs with higher content of aldehyde groups, acting as multi-role player, are crucial to limit the size of AuNPs within 10 nm. Furthermore, AuNPs with average diameter of 5.1 ± 1.0 nm are quantitative obtained at ambient temperature by reducing chloroauric acid within 1 h under conditions of pH= 10.8, 53% aldehyde content, 0.4% DACNCs and 0.25 mM gold ions. In addition, a quantitative method for monitoring the exhaustion of gold ions is established to clarify the synthetic mechanism of AuNPs. Finally, reduction of 4-nitrophenol under AuNPs catalysis is conducted to verify the superiority of as-prepared ultra-fine AuNPs.


Assuntos
Celulose/análogos & derivados , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas/química , Catálise , Celulose/química , Fenômenos Químicos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Nanocompostos/química , Análise Espectral
5.
Carbohydr Polym ; 218: 68-77, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31221345

RESUMO

Facile strategy to construct a cellulose nanocomposite hydrogel with self-healing and biocompatible properties is reported by crosslinking dialdehyde cellulose nanocrystals with acylhydrazine-terminated polyethylene glycol via dynamic reversible acylhydrazone for the first time. The effects of process variables on gelation time, mechanical strength and self-healing efficiency of hydrogels were investigated. It was found that gelation time shortened from hours to seconds by adjusting gelator and catalyst concentration. Tensile and compressive strength of hydrogel could reach 141 K Pa and 580 K Pa at 20.1% gelator concentration, respectively. Interestingly, the as-prepared hydrogel presented excellent self-healing ability without additional stimuli whose healing efficiency was higher than 90% even at higher gelator concentration. Furthermore, Cytotoxicity test showed that cell viability almost reached 100% after culturing with hydrogel, which revealed the hydrogel was biocompatible.


Assuntos
Materiais Biocompatíveis/química , Celulose/química , Hidrazonas/química , Hidrogéis/química , Nanocompostos/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Celulose/síntese química , Celulose/toxicidade , Força Compressiva , Hidrazonas/síntese química , Hidrazonas/toxicidade , Hidrogéis/síntese química , Hidrogéis/toxicidade , Concentração de Íons de Hidrogênio , Camundongos , Nanocompostos/toxicidade , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Resistência à Tração
6.
Carbohydr Polym ; 207: 68-78, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600053

RESUMO

We report a facile and effective method to fabricate clickable alkyne-functionalized cellulose fibers (ACFs) through in situ chemical oxidation copolymerization of 3-ethynylaniline and aniline under acidic aqueous solution. The effects of process variables on copolymer deposition onto CFs were investigated and suitable preparation conditions were identified. It was found that aniline significantly facilitated the polymerization of 3-ethynylaniline and shortened the preparation time of ACFs from 48 to 6 h. Antibacterial-modified cellulose fibers were prepared by binding ß-cyclodextrin (ß-CD) to cellulose fibers via click chemistry, followed by the inclusion of ciprofloxacin hydrochloride (CipHCl). The loading and releasing behaviors of CipHCl into/from click product (ACFs@Azide-ß-CD) were also revealed. The load amount of CipHCl into ACFs@Azide-ß-CD increased remarkably, and the release of CipHCl from ACFs@Azide-ß-CD was prolonged. The ACFs@Azide-ß-CD loaded with CipHCl exhibited higher and longer-term antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureu) compared with CFs and ACFs.

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