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1.
Curr Issues Mol Biol ; 46(9): 9821-9830, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39329935

RESUMO

Porcine sapelovirus (PSV) is a new pathogen that negatively impacts the pig industry in China. Affected pigs experience severe diarrhea and even death. Vaccination is used to control disease outbreaks, and sensitive diagnostic methods that can distinguish infected animals from vaccinated animals (DIVA) are essential for monitoring the effectiveness of disease control programs. Tests based on the detection of the nonstructural protein (NSP) 3AB are reliable indicators of viral replication in infected and vaccinated animals. In this study, the recombinant PSV 3AB protein was expressed by a prokaryotic expression system, and an indirect ELISA method was established. Serum samples from healthy animals, immunized animals, and infected animals were evaluated. The ELISA method identified 3AB with high sensitivity (99.78%) and specificity (100.0%), and no cross-reaction was observed with serum antibodies against porcine reproductive and respiratory syndrome virus (PRRSV), infection with classical swine fever virus (CSFV), pseudorabies virus (PRV), bovine viral diarrhea virus (BVDV), porcine epidemic diarrhea virus (PEDV), or foot-and-mouth disease virus (FMDV). The ELISA method described here can effectively distinguish infected and vaccinated animals and is an important inexpensive tool for monitoring serum and controlling PSV.

2.
Hereditas ; 156: 31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31548836

RESUMO

BACKGROUND: Cleidocranial dysplasia (CCD) is a rare autosomal dominant disorder mainly characterized by hypoplastic or absent clavicles, delayed closure of the fontanelles, multiple dental abnormalities, and short stature. Runt-related transcription factor 2 (RUNX2) gene variants can cause CCD, but are not identified in all CCD patients. METHODS: In this study, we detected genetic variants in seven unrelated children with CCD by targeted high-throughput DNA sequencing or Sanger sequencing. RESULTS: All patients carried a RUNX2 variant, totally including three novel pathogenic variants (c.722_725delTGTT, p.Leu241Serfs*8; c.231_232delTG, Ala78Glyfs*82; c.909C > G, p.Tyr303*), three reported pathogenic variants (c.577C > T, p.Arg193*; c.574G > A, p.Gly192Arg; c.673 C > T, p.Arg225Trp), one likely pathogenic variant (c.668G > T, p.Gly223Val). The analysis of the variant source showed that all variants were de novo except the two variants (c.909C > G, p.Tyr303*; c.668G > T, p.Gly223Val) inherited from the patient's father and mother with CCD respectively. Further bioinformatics analysis indicated that these variants could influence the structure of RUNX2 protein by changing the number of H-bonds or amino acids. The experimental result showed that the Gly223Val mutation made RUNX2 protein unable to quantitatively accumulate in the nucleus. CONCLUSIONS: The present study expands the pathogenic variant spectrum of RUNX2 gene, which will contribute to the diagnosis of CCD and better genetic counseling in the future.


Assuntos
Displasia Cleidocraniana/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Núcleo Celular , Criança , Pré-Escolar , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino , Mutação , Linhagem
3.
Langmuir ; 32(11): 2698-707, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-26927024

RESUMO

Both ion-specific interaction and carbon spacer length have strong effects on the properties of polyzwitterions. In this work, we have investigated the anion specificity of poly(sulfobetaine methacrylamide) (PSBMAm) brushes with different carbon spacer lengths. The effectiveness of anions to enhance the hydration of the PSBMAm brushes increases from kosmotropic to chaotropic anions. The interactions between the anions and the PSBMAm brushes are strongly influenced by carbon spacer length because the strength of inter/intrachain association of the PSBMAm brushes decreases with increasing carbon spacer length. The inter/intrachain association of the PSBMAm brushes with a longer carbon spacer is easier to break by the external anions in the high salt concentration regime. On the other hand, a longer carbon spacer is more favorable for the zwitterionic groups to form cyclic intramolecular structures. As a result, the addition of anions can more effectively enhance the hydration of the PSBMAm brushes with a medium-length carbon spacer compared with that of the PSBMAm brushes with a either shorter or longer carbon spacer in the low salt concentration regime, determined by the balance between the inter/intrachain association and the formation of cyclic intramolecular structures. Our study also demonstrates that both anion identity and carbon spacer length can be used to control protein adsorption on the surface of the PSBMAm brushes.


Assuntos
Resinas Acrílicas/química , Betaína/análogos & derivados , Betaína/química , Soroalbumina Bovina/química , Resinas Acrílicas/síntese química , Adsorção , Animais , Ânions , Betaína/síntese química , Bovinos , Estrutura Molecular , Muramidase/química , Água
4.
Int J Biol Macromol ; 274(Pt 2): 133470, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38942401

RESUMO

Passive daytime radiative cooling (PDRC) technology offers a green and sustainable strategy for cooling, eliminating the need for external energy sources through its exceptional efficiency in heat radiation and sunlight reflection. Despite its benefits, the widespread usage of non-biodegradable PDRC materials has unfortunately caused environmental pollution and resource wastage. Furthermore, the effectiveness of outdoor PDRC materials can be significantly diminished by rainfall. In this work, a superhydrophobic composite aerogel composed of stereocomplex-type polylactide and ultra-fine glass fiber has been successfully developed through simple physical blending and freeze-drying, which exhibits low thermal conductivity (36.26 mW m-1 K-1) and superhydrophobicity (water contact angle up to 150°). Additionally, its high solar reflectance (91.68 %) and strong infrared emissivity (93.95 %) enable it to effectively lower surface temperatures during daytime, resulting in a cooling effect of approximately 3.8 °C below the ambient temperature during the midday heat of summer, with a cooling power of 68 W/m2. This aerogel offers an environmentally friendly and sustainable approach for the utilization of radiative refrigeration materials, paving the way for environmental protection and sustainable development.


Assuntos
Géis , Vidro , Interações Hidrofóbicas e Hidrofílicas , Poliésteres , Vidro/química , Poliésteres/química , Géis/química , Condutividade Térmica , Temperatura Baixa , Temperatura
5.
Int J Biol Macromol ; 232: 123422, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36708887

RESUMO

Ultra-tough and heat-resistant poly(l-lactide)/core-shell rubber (PLLA/CSR) blends were fabricated by utilizing stereocomplex (SC) crystallites to effectively regulate the CSR distribution in PLLA matrix. Linear and 3-11 armed poly(d-lactide)s (PDLAs) were synthesized and then melt-mixed with PLLA/CSR blend. Interestingly, the incorporated PDLA chains could collaborate with PLLA chains to form dense SC crystallites network in PLLA/PDLA/CSR blends, thus inducing the CSR particles to transform from uniform distribution structure to network-like structure. With increasing the PDLA arm numbers, the size of CSR clusters in the network-like structure first increased and then decreased, and the continuity of the network-like structure first remained at a high level and then decreased obviously. The formation of CSR network-like structure could remarkably improve the impact strength of PLLA/PDLA/CSR blends without deteriorating their strength and modulus (compared with PLLA/CSR blend), and the CSR network-like structure with larger-sized CSR clusters and higher continuity could help obtain higher impact strength (78.3 kJ/m2). Moreover, the heat resistance of PLLA/PDLA/CSR blends could also be significantly improved (the highest Vicat softening temperature was 131 °C) by the SC crystallites network and CSR network-like structure. This work provides an effective strategy for controlling the rubber network-like morphology and thereby preparing high-performance PLLA materials.


Assuntos
Temperatura Alta , Poliésteres , Cristalização , Estereoisomerismo , Poliésteres/química
6.
Bioresour Technol ; 360: 127539, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35777640

RESUMO

Tobacco stems (TS) are tobacco residues produced, whereby the assessment of the pyrolysis kinetics of TS is critical to realize high-value utilization of agricultural residues. Firstly, a thermogravimetric analyzer was employed to perform the non-isothermal pyrolysis of TS at various heating rates. Then, the deconvolution function by Asym2sig showed that the pyrolysis of TS can be accurately modeled for three parallel decomposition fractions. Furthermore, the pyrolysis product was analyzed using fourier transform infrared spectrometer (FTIR). The results showed that the average activation energy evaluated by the isoconversion methods exhibited the highest average activation energy of 191.762 kJ·mol-1 for lignin (LG), followed by 189.268 kJ·mol-1 for cellulose (CL) and then 176.357 kJ·mol-1 for hemicellulose (HC). Based on the experimental results, the pre-exponential factors and reaction models for HC, CL and LG were also calculated and developed separately. From thermodynamic standpoint, raw materials for bioenergy generation can be derived from TS.


Assuntos
Nicotiana , Pirólise , Biomassa , Celulose/química , Cinética , Lignina/química , Termogravimetria
7.
Bioresour Technol ; 347: 126402, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34826563

RESUMO

The evaluation of pyrolysis kinetics for waste industrial hemp stem (IHS) is essential to achieve the high-value utilization of agricultural waste. In present study, firstly, non-isothermal pyrolysis experiments of IHS were performed at different heating rates using a thermogravimetric analyzer. Then, the kinetic triplets (apparent activation energy, pre-exponential factor, and reaction mechanism) of the three pseudo components for IHS (hemicellulose, cellulose, and lignin) were determined by a three-parallel-reaction model. Moreover, the pyrolysis products were also characterized via FTIR and SEM. The results showed that the apparent activation energies of hemicellulose, cellulose and lignin were 86.523, 113.257 and 197.961 kJ/mol, respectively; the pre-exponential factors were 6.887 × 107, 8.179 × 109 and 1.801 × 1015 s-1, respectively; and the reaction mechanism functions were f(α) = α1.35629(1-α)0.34832[-ln(1-α)]-1.20128, f(α) = α3.42900(1-α)0.01288[-ln(1-α)]-2.84445, f(α) = α0.68738(1-α)3.09313[-ln(1-α)]-1.58522, respectively. The release temperature for volatile products of IHS pyrolysis was mainly between 440 and 840 K. IHS as an agricultural waste is a suitable feedstock to produce renewable energy.


Assuntos
Cannabis , Pirólise , Biomassa , Cinética , Lignina , Termogravimetria
8.
ACS Appl Mater Interfaces ; 12(5): 6351-6361, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31920076

RESUMO

Programmable nonuniform deformation is of great significance for self-shape-morphing systems that are commonly seen in biological systems and also has practical applications in drug delivery, biomedical devices and robotics, etc. Here, we present a novel gradient four-dimensional (4D) printing method toward biomimetic nonuniform, dual-stimuli self-morphing. By modeling and printing graded active materials with water swelling properties, we can configure continuously smooth gradients of volume fraction of the active material in bilayer structures. The variation of swelling ratio mismatch between the two layers can be delicately regulated, which results in the programmable nonuniform shape transformation. The shape-shifting results can be predicted by the established mathematical model and computational simulations. Furthermore, we demonstrate dual-stimuli self-morphing structures by printing the graded water-responsive elastomer materials onto a heat-shrinkable shape memory polymer, which could produce different shape changes in response to humidity and different temperatures. This method pioneers a versatile approach to broaden the design space for 4D printing and will be compatible with a wide range of active materials meeting various requirements in diverse potential applications.


Assuntos
Biomimética/métodos , Impressão Tridimensional , Elastômeros/química , Análise de Elementos Finitos , Modelos Teóricos , Impressão Tridimensional/instrumentação , Temperatura
9.
Curr Pharm Des ; 26(34): 4338-4348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324508

RESUMO

BACKGROUND: PEGylation of stealth liposomes elevates their stability and prolongs plasma half-life. Stealth liposomes modified with targeting ligands are expected to be ideal drug delivery carriers. OBJECTIVE: To encapsulate docetaxel in tbFGF (truncated basic fibroblast growth factor)-functionalized liposomes with mPEG2000-VE (d-κ-tocopheryl polyethylene glycol succinate, TPGS2K) and measure their antitumor effects in vitro and in vivo. METHODS: TPGS2K and COOH-PEG2000-VE were synthesized, and tbFGF was conjugated to COOH-PEG2000-VE to prepare tbFGF-PEG2000-VE. Then, tbFGF-functionalized liposomes (DTX-tbFGF-LPs) were prepared by inserting tbFGF-PEG2000-VE into docetaxel liposomes comprising TPGS2K (DTX-PEG-LPs). The stabilities and drug release profiles of the formulation were evaluated. P-glycoprotein (P-gp) inhibition was measured by ATPase assay. MTT and cell uptake were measured with B16 cells. A B16 C57BL/6 mouse model was used to evaluate in vivo antitumor efficacy. RESULTS: Both DTX-PEG-LPs and DTX-tbFGF-LPs exhibited good stability and sustained drug release. MTT, flow cytometry, and fluorescence microscopy of B16 cells revealed higher antitumor activity and more efficient cell uptake for DTX-tbFGF-LPs compared with DTX-PEG-LPs and DTX-LPs. The P-gp ATPase assay showed that both PEG-LP and tbFGF-PEG-LP formulations inhibited P-gp pump activity in vitro. DTX-tbFGF-LPs had the highest antitumor efficacy and lowest toxicity in vivo. CONCLUSION: Truncated basic fibroblast growth factor-functionalized liposomes with TPGS2K as drug delivery nanocarriers were effective chemotherapy agents targeting FGFR-overexpressing tumors.


Assuntos
Antineoplásicos , Lipossomos , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Docetaxel/farmacologia , Fator 2 de Crescimento de Fibroblastos , Camundongos , Camundongos Endogâmicos C57BL , Polietilenoglicóis , Succinatos , Vitamina E
10.
Nanomedicine (Lond) ; 14(11): 1371-1386, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31215328

RESUMO

Aim: The potential bio-related risks of dextran-coated ultra-small superparamagnetic particles of iron oxides (D-USPIO) were assessed. Materials & methods: Metabolic responses of D-USPIO in BALB/C mice were obtained using 1H-NMR-based metabolomic strategy combined with the traditional biochemical assay. Results: The metabolomic analyses of biological fluids (plasma and urine) and organs (liver, kidney and spleen) indicated that the disturbance, impairment and recovery of the physiological functions were related to the metabolic response to D-USPIO. The correlations between the biofluids and tissue metabolomes described the specific metabolic information of D-USPIO on their in vivo transportation, absorption, biodistribution and excretion. Conclusion: Metabolomic analysis provides preliminary validation for the use of D-USPIO in clinical medicine, and the results help to understand the potential adverse effects of the similar bio-nanomaterials further serve to their synthesis optimization and biocompatibility improvement.


Assuntos
Materiais Revestidos Biocompatíveis/química , Meios de Contraste/farmacocinética , Dextranos/química , Nanopartículas de Magnetita/química , Animais , Meios de Contraste/administração & dosagem , Rim/metabolismo , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Nanopartículas de Magnetita/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Plasma/química , Baço/metabolismo , Distribuição Tecidual , Urina/química
11.
J Biomed Nanotechnol ; 15(7): 1515-1531, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31196355

RESUMO

In our previous study, we identified a class of 4-substituted coumarins as a powerful microtubule inhibitors binding to the colchicine site of ß-tubulin. H6 showed potent anti-proliferative ability with IC50 values from 7 to 47 nM, and remarkable ability to reduce tumor growth in several xenograft models including taxol resistant tumor models. However, the extremely hydrophobicity limited its clinical application. In this study, to improve the anticancer activity and reduce the toxicity of H6, we successfully prepared MPEG-PCL with different proportions and H6-loaded polymeric micelles (H6/MPEG2kPCL2k micelles) by a simple thin-film hydration method. The prepared H6/MPEG-PCL micelles had a drug loading of 3.79 ± 0.001%, an encapsulation efficiency of 98.00 ± 0.41%, a mean particle size of 30.45 ± 0.18nm and a polydispersity index (PDI) of 0.096 ± 0.009. Computer simulation results revealed a good compatibility of H6 and MPEG2k-PCL2k copolymer. In in vitro release study and pharmacokinetic study showed H6 micelles can release H6 over an extended period. Furthermore, H6 micelles possessed comparative effect as free H6 in inhibiting cell growth, preventing cell migration, and inducing apoptosis. Mechanism study identified that H6 is a novel reversible microtubule inhibitor. In in vivo studies, H6 micelles exhibited tumor growth inhibition on two pulmonary metastatic tumor models (B16/F10 and 4T1). Importantly, H6 micelles significantly improved the solubility, reduced the toxicity, extended the half-life of drugs, and augmented the therapeutic window. All these results imply that H6 micelles have great potential for suppression of tumor metastasis.


Assuntos
Cumarínicos/química , Linhagem Celular Tumoral , Simulação por Computador , Portadores de Fármacos , Humanos , Micelas , Paclitaxel , Tamanho da Partícula , Poliésteres , Polietilenoglicóis
12.
J Biomed Nanotechnol ; 14(7): 1225-1238, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29944097

RESUMO

To achieve higher therapeutic efficiency with catabatic side effects, desirable nanocarriers should be designed to retain the loaded drug tightly during the systemic circulation, but release the drug rapidly and efficiently upon endocytosis by tumor cells. Herein, we synthesized a novel folate conjugated poly(ethylene glycol)-poly(L-glutamic acid)-poly(L-phenylalanine) (folate-PEG-PLG(HS)-PPhe) copolymer to achieve a desired controlled delivery of doxorubicin (DOX). The copolymer could self-assemble into interlayer-crosslinked micelles with reduction sensitivity, and DOX was successfully loaded into the interior of copolymer. The interlayer-crosslinked disulfide bond at the intermediate region of between PEG and poly(L-phenylalanine) led to significant improvement of the system stability through the introduction of an additional mechanism of carrier/carrier interaction. The crosslinked interlayer could be cleaved at the desired target site under tumor-relevant reductive conditions and DOX were rapidly released from the DOX loaded folate-PEG-PLG (HS)-PPhe micelles (DOX-fPGPM), and significantly lowered the drug leakage without glutathione (GSH). Importantly, the DOX-fPGPM exhibited significantly higher antitumor efficiency both in vitro and in vivo in comparison with free DOX, and Doxil (commercial doxorubicin-loaded liposomes). Biodistribution studies showed that DOX more effectively accumulated in tumor tissue after iv injection of DOXfPGPM. The DOX-fPGPM designed in this work potentially resolved the dilemma between systemic stability and rapid intracellular drug release, and would provide a promising nanomedicine platform for cancer therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Doxorrubicina , Portadores de Fármacos , Humanos , Micelas , Polietilenoglicóis , Distribuição Tecidual
13.
Colloids Surf B Biointerfaces ; 136: 160-7, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26387067

RESUMO

We describe the development of novel reduction-sensitive therapeutic micelles consisting of polyethylene glycol-poly-(l-glutamic acid) (PEG-PLG), and conjugate with dithiodipropionic-Pt (IV) (DTDP-Pt). The drug delivery polymeric micelles lie in the covalent conjugation of each cisplatin drug to the PLG chains through a disulfide bond. The resulting micelles show well-controlled cisplatin loading yield, excellent reduction-responsive drug release kinetics, and enhanced in vitro cytotoxicity against cancer cells. The in vivo studies on the subcutaneous human ovarian carcinoma SKOV-3 xenograft model confirmed that PEG-P(LG-DTDP-Pt) micelles showed significant antitumor activity and reduced side effects, compared with free cisplatin. This characteristic drug release profile holds the promise to suppress cancer cell by rapidly releasing a high dose of chemotherapy drugs inside the tumor cells, thereby improving the therapeutic efficacy of the drug payload.


Assuntos
Antineoplásicos/administração & dosagem , Cisplatino/administração & dosagem , Polímeros/química , Pró-Fármacos/química , Animais , Linhagem Celular Tumoral , Humanos , Técnicas In Vitro , Camundongos , Micelas , Oxirredução , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Pharm Sci ; 104(11): 3934-3942, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26306026

RESUMO

This work aims to improve the solubility of 7-ethyl-14-aminocamptothecin (EACPT) by encapsulating it into monomethoxy poly(ethylene glycol)2000 -poly(lactic acid)2000 (MPEG-PLA) polymeric micelles. Micelles were prepared by a solid dispersion method; the properties including particle size distribution, morphology, drug loading, entrapment efficiency, crystallography property, solubility, and stability were characterized in detail. The results demonstrated that the EACPT-loaded MPEG-PLA polymeric micelle (EACPT-M) was successfully developed with a small particle size of 20.7 ± 0.2 nm, and the solubility was increased approximately 800-fold compared with free drug. In vitro release study showed sustained-release behavior of EACPT-M. Cytotoxicity assay suggested the incorporated EACPT maintained the potent antitumor effect of free drug. Furthermore, the obtained EACPT-M (1 mg/mL) did not induce hemolysis in vitro. Additionally, EACPT-M exhibited significant tumor growth inhibition in H460 human tumor xenograft model. The results indicated that the EACPT-M was a water-soluble, safe, and effective delivery system for human cancer chemotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Camptotecina/análogos & derivados , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Preparações de Ação Retardada/química , Neoplasias Pulmonares/tratamento farmacológico , Micelas , Poliésteres/química , Polietilenoglicóis/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Camptotecina/administração & dosagem , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células Hep G2 , Humanos , Ácido Láctico/química , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Camundongos Nus , Polímeros/química
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