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1.
Molecules ; 28(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36771056

RESUMEN

Soy protein isolate (SPI) is an attractive natural material for preparing wood adhesives that has found broad application. However, poor mechanical properties and unfavorable water resistance of wood composites with SPI adhesive bonds limit its more extensive utilization. The combination of lysine (Lys) with a small molecular structure as a curing agent for modified soy-based wood adhesive allows Lys to penetrate wood pores easily and can result in better mechanical strength of soy protein-based composites, leading to the formation of strong chemical bonds between the amino acid and wood interface. Scanning electron microscopy (SEM) results showed that the degree of penetration of the S/G/L-9% adhesive into the wood was significantly increased, the voids, such as ducts of wood at the bonding interface, were filled, and the interfacial bonding ability of the plywood was enhanced. Compared with the pure SPI adhesive, the corresponding wood breakage rate was boosted to 84%. The wet shear strength of the modified SPI adhesive was 0.64 MPa. When Lys and glycerol epoxy resin (GER) were added, the wet shear strength of plywood prepared by the S/G/L-9% adhesive reached 1.22 MPa, which increased by 29.8% compared with only GER (0.94 MPa). Furthermore, the resultant SPI adhesive displayed excellent thermostability. Water resistance of S/G/L-9% adhesive was further enhanced with respect to pure SPI and S/GER adhesives through curing with 9% Lys. In addition, this work provides a new and feasible strategy for the development and application of manufacturing low-cost, and renewable biobased adhesives with excellent mechanical properties, a promising alternative to traditional formaldehyde-free adhesives in the wood industry.


Asunto(s)
Lisina , Proteínas de Soja , Proteínas de Soja/química , Lisina/análisis , Resinas Epoxi/análisis , Adhesivos/química , Madera/química , Agua/análisis
2.
Anal Bioanal Chem ; 409(13): 3309-3317, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28258465

RESUMEN

As one of the most important posttranslational modifications, protein phosphorylation plays an important role in vital movement. However, an efficiency enrichment treatment prior to MS detection is still a crucial step to protein phosphorylation analysis. In this work, a novel hybrid microsphere for efficient phosphopeptide enrichment was prepared by reverse-phase suspension polymerization of cellulose derivative and chitosan. The microspheres bore different kinds of amine groups and the main enrichment mechanism was based on anion exchange. This approach exhibited high selectivity for phosphopeptides from ß-casein, α-casein, and non-fat milk. Three phosphopeptides could still be detected when the amount of ß-casein was as low as 10 fmol. This study demonstrated a new attractive solid-phase support for phosphopeptide enrichment to meet the increasing need of phosphoproteomics analysis.


Asunto(s)
Celulosa/química , Quitosano/química , Fosfopéptidos/química , Animales , Leche/química , Estructura Molecular , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
3.
Carbohydr Polym ; 334: 122068, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38553197

RESUMEN

The fabrication of highly elastic, fatigue-resistant and conductive hydrogels with antibacterial properties is highly desirable in the field of wearable devices. However, it remains challenging to simultaneously realize the above properties within one hydrogel without compromising excellent sensing ability. Herein, we fabricated a highly elastic, fatigue-resistant, conductive, antibacterial and cellulose nanocrystal (CNC) enhanced hydrogel as a sensitive strain sensor by the synergistic effect of biosynthesized selenium nanoparticles (BioSeNPs), MXene and nanocellulose. The structure and potential mechanism to generate biologically synthesized SeNPs (BioSeNPs) were systematically investigated, and the role of protease A (PrA) in enhancing the adsorption between proteins and SeNPs was demonstrated. Additionally, owing to the incorporation of BioSeNPs, CNC and MXene, the synthesized hydrogels showed high elasticity, excellent fatigue resistance and antibacterial properties. More importantly, the sensitivity of hydrogels determined by the gauge factor was as high as 6.24 when a high strain was applied (400-700 %). This study provides a new horizon to synthesize high-performance antibacterial and conductive hydrogels for soft electronics applications.


Asunto(s)
Nanopartículas , Nitritos , Selenio , Elementos de Transición , Antibacterianos/farmacología , Celulosa/farmacología , Conductividad Eléctrica , Hidrogeles/farmacología
4.
Ann Palliat Med ; 10(6): 7114-7120, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34118834

RESUMEN

Antiphospholipid syndrome (APS) is an autoimmune systemic disorder characterized by arterial, venous, or small vessel thrombosis, and/or recurrent early pregnancy loss, fetal loss, or pregnancy morbidity. APS is induced by persistent positive antiphospholipid antibodies (aPL), the main being lupus anticoagulant (LA), and/or anticardiolipin (aCL) antibodies, and/or anti-beta 2 glycoprotein 1 (ß2-GP1) antibodies. Some studies have shown that the incidence of APS is about 5 new cases per 100,000 persons per year, and the prevalence is around 40-50 cases per 100,000 persons. APS can be primary or secondary. Secondary APS often coexists with another autoimmune disorder, most commonly systemic lupus erythematosus (SLE). Behcet's disease (BD) is usually characterized by recurrent oral and genital aphthous ulcers and ocular involvement. It can occasionally affect the venous system. BD usually affects small vessels, but can sometimes affect large veins or even a variety of veins. Because most of APS is secondary to SLE, APS secondary to incomplete BD is quite rare. This report describes a case in which a 15-year-old male experienced bilateral leg swelling and pain. The patient had a long history of self-healing recurrent mouth ulcers. Laboratory tests revealed positive ß2-GP1 immunoglobulin A (IgA). His symptoms improved by using steroids, prednisolone, uro-kinase, and hirudin. In this rare case of secondary APS, the patient was diagnosed with anti-ß2-GP-1 IgA positive to incomplete BD. It is a rare case of secondary APS with positive anti-ß2-GP1 IgA to incomplete BD. It is suggested that patients with recurrent mouth ulcers should be closely examined to prevent thrombosis, and more laboratory markers should be used to avoid a risk of misdiagnosing patients with APS.


Asunto(s)
Aborto Habitual , Síndrome Antifosfolípido , Síndrome de Behçet , Adolescente , Pérdida del Embrión , Femenino , Humanos , Inmunoglobulina A , Masculino , Embarazo , beta 2 Glicoproteína I
5.
Anal Biochem ; 407(2): 211-9, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-20804720

RESUMEN

We describe here the conjugation of polyclonal goat anti-rabbit antibody to generation 4 polyamidoamine (G4-PAMAM) dendrimers carrying (i) (η(5)-cyclopentadienyl) iron dicarbonyl succinimidato complexes as infrared (IR) probes, (ii) nitroaniline entities as nuclear magnetic resonance (NMR) probes, (iii) acetamide groups for surface neutralization, and (iv) hydrazide-terminated spacer arms for the reaction with aldehyde. To preserve a high binding affinity, the conjugation was performed on the carbohydrate moieties located on the Fc fragment. The resulting conjugates were characterized by Fourier transform-IR, ultraviolet (UV), and high-mass matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. On the basis of relative concentration ratios of IR probes and antibody, an average labeling of 30 IR probes per antibody was reached (i.e., more than twice the value obtained with our previous strategy that generated no spacer arm). Immunoassays revealed that the antibody-dendrimer conjugates retained 55.1% of immunoreactivity on average with respect to underivatized antibody. Finally, the conjugates were used to quantify their antigen by solid-phase carbonyl metallo immunoassay (CMIA). Results showed a significant enhancement of the IR signal, demonstrating the efficiency of the new conjugation strategy and the potential of the new antibody-dendrimer conjugates as universal immunoanalytical reagents.


Asunto(s)
Anticuerpos/química , Complejos de Coordinación/química , Dendrímeros/química , Inmunoensayo/métodos , Hierro/química , Nylons/química , Animales , Anticuerpos/inmunología , Espectroscopía de Resonancia Magnética , Conejos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrofotometría Ultravioleta
6.
J Control Release ; 316: 236-249, 2019 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-31672624

RESUMEN

The macrophages mediated inflammation participates in every stage of atherosclerosis. Attenuation of macrophages inflammatory responses by active ingredients in atherosclerotic plaques is benefit to atherosclerotic stabilization and regression, but meanwhile, it is highly desired to develop accurate therapeutics for reducing off-target effects. Previous studies revealed that the apoptotic bodies are effectively recognized and engulfed by macrophages own to increased exposure of phosphatidylserine (PtdSer), which is regarded as a key "eat-me" signal. To achieve optimal delivery efficiency, an apoptotic body biomimic liposome (AP-Lipo) is constructed by decorating PtdSer and DSPE-PEG2000-cRGDfK onto the surface of liposome for selectively delivering pioglitazone (PIO), a peroxisome proliferator-activated receptor γ (PPARγ) agonist, into atherosclerotic macrophages while minimizing its side effects. Compared with unmodified liposome, AP-Lipo is more effective to recognize and penetrate the activated vascular endothelial monolayer, target pro-inflammatory macrophages and suppress the inflammation by upreglation of anti-inflammatory cytokines in vitro. Moreover, AP-Lipo can effectively target to atherosclerotic plaques and imped the progression of atherosclerosis by upregulating anti-inflammatory macrophages number and stabilizing the atherosclerotic plaques. In summary, this design imitates the characteristic of apoptotic body and provides a potential drug delivery system for atherosclerosis and other diseases, which attribute to inflammation mediated by macrophages.


Asunto(s)
Sistemas de Liberación de Medicamentos , Inflamación/tratamiento farmacológico , Pioglitazona/administración & dosificación , Placa Aterosclerótica/tratamiento farmacológico , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacología , Apolipoproteínas E/genética , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/patología , Materiales Biomiméticos/química , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Inflamación/patología , Liposomas , Macrófagos/metabolismo , Ratones Noqueados , PPAR gamma/agonistas , Pioglitazona/farmacología , Placa Aterosclerótica/patología
7.
J Control Release ; 259: 195-202, 2017 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-28389408

RESUMEN

Using recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) as a model drug, the present study demonstrated a practically feasible process to produce polymeric microspheres for sustained-release delivery of protein drugs with preserved integrity. This process is featured with pre-loading proteins into polysaccharide fine particles via a self-standing aqueous-aqueous "emulsion", prior to microencapsulation into the microspheres. The protein drug, rhGM-CSF, was partitioned thermodynamically into a dextran dispersed phase of the aqueous-aqueous emulsion, followed by lyophilization and removal of the polyethylene glycol (PEG) continuous phase (using an organic solvent not penetrating into dextran matrix). The harvested dextran particles were then suspended in a dichloromethane solution of polylatic-co-glyclic acids (PLGA) and emulsified in a polyvinyl alcohol (PVA) and NaCl solution of small volume to form embryonic microspheres. The emulsion was then transferred into a NaCl solution of large volume to extract the organic solvent and harden the embryonic microspheres. The obtained rhGM-CSF microspheres showed a satisfied release profile with the day-to-day variation within 9 folds over the multi-weeks long release period. At the same time, the integrity (defined freedom of aggregates measured by SEC-HPLC) and bioactivity (defined by TF-1 cell proliferation) of the proteins were well preserved. The present formulation process ensured good reproducibility and over 89% protein encapsulation efficiency, and practically feasible to adapt to scaled productions.


Asunto(s)
Preparaciones de Acción Retardada/administración & dosificación , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Microesferas , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Dextranos/química , Liberación de Fármacos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/sangre , Factor Estimulante de Colonias de Granulocitos y Macrófagos/química , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacocinética , Humanos , Ácido Láctico/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Wistar
8.
PLoS One ; 10(2): e0117358, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25710485

RESUMEN

BACKGROUND: HIFU has been shown to be a more suitable alternative for the treatment of primary solid tumors and metastatic diseases than other focal heat ablation techniques due to its noninvasive and extracorporeal nature. However, similar to other focal heat ablation techniques, HIFU is still in need of refinements due to tumor recurrence. METHODS: In this work, we investigated the effectiveness of an adjunct treatment regimen using doxorubicin (DOX)-loaded, injectable, in situ-forming, and phase-inverting PLGA as the second line of defense after HIFU ablation to destroy detrimental residual tumors and to prevent tumor recurrence. All of the statistical analyses were performed using the Statistical Package for the Social Sciences 18.0 (SPSS, Inc., Chicago, IL, USA), and p<0.05 was considered statistically significant. All of the results are presented as the means ± STDEV (standard deviation). For multiple comparisons, ANOVA (differences in tumor volumes, growth rates, apoptosis, proliferation indexes, and Bcl-2 and Bax protein levels) was used when the data were normally distributed with homogenous variance, and rank sum tests were used otherwise. Once significant differences were detected, Student-t tests were used for comparisons between two groups. RESULTS: Our results revealed that DOX diffused beyond the ablated tissue regions and entered tumor cells that were not affected by the HIFU ablation. Our results also show that HIFU in concert with DOX-loaded PLGA led to a significantly higher rate of tumor cell apoptosis and a lower rate of tumor cell proliferation in the areas beyond the HIFU-ablated tissues and consequently caused significant tumor volume shrinkage (tumor volumes:0.26±0.1,1.09±0.76, and 1.42±0.9 cm3 for treatment, sham, and no treatment control, respectively). CONCLUSIONS: From these results, we concluded that the intralesional injection of DOX-loaded PLGA after HIFU ablation is significantly more effective than HIFU alone for the treatment of solid tumors.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Ultrasonido Enfocado de Alta Intensidad de Ablación , Ácido Láctico/química , Neoplasia Residual/tratamiento farmacológico , Ácido Poliglicólico/química , Animales , Antibióticos Antineoplásicos/química , Apoptosis , Doxorrubicina/química , Portadores de Fármacos/química , Microburbujas , Neoplasia Residual/diagnóstico por imagen , Neoplasia Residual/patología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Conejos , Neoplasias Cutáneas/patología , Resultado del Tratamiento , Ultrasonografía , Proteína X Asociada a bcl-2/metabolismo
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