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1.
Polymers (Basel) ; 15(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37177187

RESUMO

The ternary blends of a high content of thermoplastic starch (TPS), poly(butylenes adipate-co-terephthalate) (PBAT), and poly(butylene succinate) (PBS) were first melt-compounded in a twin screw extruder. The TPS contents in ternary blends were fixed at 60 wt%. The miscibility, morphology, thermal behavior, mechanical properties, and thermal resistance of the blends were investigated. The results showed that dispersions of PBS and PBAT minor phases improved the tensile strength and elongation at break. TPS/PBS/PBAT60/10/30 formed a good balance in strength and toughness. Dynamic mechanical analysis of the blends exhibits an intermediate and peak suggesting the ternary blend is compatible. Minor phase-separated structure SEM results showed that TPS/PBS/PBAT60/10/30 blend formed a typical mixture with core-shell morphology. As the PBAT composition was increased, phase morphology changes occurred in the blends, leading to decreased values of complex viscosity, storage modulus, and loss modulus. Moreover, the thermal resistances and melt flow properties of the materials were also studied by analysis of the heat deflection temperature (HDT) and melt flow index (MFI) value in the work.

2.
Pharm Biol ; 61(1): 1-11, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36537316

RESUMO

CONTEXT: Atherosclerosis (AS) is the main cause of cardiovascular and cerebrovascular diseases. Pueraria lobata (Willd.) Ohwi (Fabaceae) has a positive effect on improving these diseases. OBJECTIVE: The P. lobata effect on the proliferation and inflammation of vascular smooth muscle in AS and the potential mechanism were investigated. MATERIALS AND METHODS: By feeding a high-fat diet to 8-week-old apolipoprotein E knockout mice, an atherosclerosis model was created. H&E and IHC staining were used to analyse the histopathology of mice. CCK-8, TUNEL, and scratch tests were used to detect cell proliferation, apoptosis, and migration after 24 h treatment, respectively. ELISA was performed to evaluate the level of IL-6 and IL-8. The target miRNA and its downstream target gene were screened by the bioinformatics method; RT-qPCR has conducted to analyse the expression of these genes. RESULTS: In the aortic tissue and serum of AS mice, puerarin can lower the expression of α-SMA and the inflammatory proteins IL-6 and IL-8. Puerarin (200 M) decreased hVSMC proliferation, migration, and IL-6 and IL-8 secretion by more than half. The inhibitory impact of puerarin on hVSMC was decreased by overexpression of miR-29b-3p. IGF1 was miR-29b-3p's downstream target gene. IGF1 expression increased almost 3-fold in AS mice and hVSMC, but miR-29b-3p mimic inhibited it. The effect of miR-29b-3p on hVSMC was reversed when IGF1 was overexpressed. DISCUSSION AND CONCLUSIONS: Puerarin inhibits the proliferation and inflammation of vascular smooth muscle in AS through the miR-29b-3p/IGF1 pathway. Puerarin may have a beneficial effect in the treatment of atherosclerosis and offer a novel therapy option.


Assuntos
Aterosclerose , MicroRNAs , Pueraria , Camundongos , Animais , Músculo Liso Vascular/metabolismo , Interleucina-6 , Interleucina-8 , MicroRNAs/genética , Proliferação de Células , Inflamação
3.
Polymers (Basel) ; 14(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36559917

RESUMO

In recent years, with the development of green environmental protection, starch film has become of interest due to the wide availability of sources, low price, and biodegradability. Amylose/polyvinyl alcohol (PVA) blend films crosslinked with different amounts of glutaraldehyde (GLU) were prepared by a solution casting method. The cross-linking degree, water sorption, tensile property, crystallization and section morphology of the films were examined. With the increase in glutaraldehyde concentration, the cross-linking degree of the blend film was improved. The wide-angle X-ray scattering (WAXS) result indicated that cross-linking hindered the crystallization of film. The section morphology of films was examined by scanning electron microscope (SEM). The results showed that the cross-linking degree of amylose film improved while the crystallinity decreased with the increase in glutaraldehyde content. Cross-linking had no obvious effect on the water sorption property of the blend films. The cross-linking modification significantly enhanced the tensile strength and Young's modulus, while it reduced the elongation at break of the blend films. It was found that the film with 0.5 wt % glutaraldehyde possessed the best performance: the tensile strength increased by 115%, while the elongation at break decreased by 18% even at high relative humidity (RH) of 90% compared to non-crosslinked films. The developed amylose/PVA blend films have promising application prospects as agricultural mulch films and packaging materials.

4.
Bioresour Technol ; 282: 222-227, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30870687

RESUMO

To ensure a sustainable future, it is imperative to efficiently utilize abundant biomass to produce such as platform chemicals, transport fuels, and other raw materials; hydrochar is one of the promising candidates derived by hydrothermal carbonization of biomass in pressurized hot water. The synthesis of "hydrochar-wrapped Ti3AlC2-derived nanofibers" was successfully achieved by a facile one-pot hydrothermal reaction using glucose as the hydrochar precursor. Meanwhile, cellulose and pinewood sawdust as raw materials were also investigated. Products were characterized by XRD, N2 adsorption-desorption isotherms, SEM, TEM and FT-IR to investigate their crystal structures, textural properties, morphologies, and surface species. In the adsorption test to remove Cd(II) and Cu(II) in aqueous solution, hydrochar-wrapped nanofibers outperformed pure nanofibers derived from Ti3AlC2, hydrothermal carbon derived from glucose and commercial activated carbon. Finally, the regeneration, sorption kinetics, and possible adsorption mechanism were also explored.


Assuntos
Alumínio/química , Cádmio/isolamento & purificação , Carvão Vegetal/química , Cobre/isolamento & purificação , Nanofibras , Titânio/química , Adsorção , Biomassa , Cinética
5.
Neurobiol Aging ; 36(7): 2248-2259, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25930235

RESUMO

Patients with Alzheimer's disease (AD) display amyloidopathy and tauopathy. In mouse models of AD, pharmacological inhibition using small molecule enzyme inhibitors or genetic inactivation of acyl-coenzyme A (Acyl-CoA):cholesterol acyltransferase 1 (ACAT1) diminished amyloidopathy and restored cognitive deficits. In microglia, ACAT1 blockage increases autophagosome formation and stimulates amyloid ß peptide1-42 degradation. Here, we hypothesize that in neurons ACAT1 blockage augments autophagy and increases autophagy-mediated degradation of P301L-tau protein. We tested this possibility in murine neuroblastoma cells ectopically expressing human tau and in primary neurons isolated from triple transgenic AD mice that express mutant forms of amyloid precursor protein, presenilin-1, and human tau. The results show that ACAT1 blockage increases autophagosome formation and decreases P301L-tau protein content without affecting endogenous mouse tau protein content. In vivo, lacking Acat1 decreases P301L-tau protein content in the brains of young triple transgenic AD mice but not in those of old mice, where extensive hyperphosphorylations and aggregation of P301L-tau take place. These results suggest that, in addition to ameliorating amyloidopathy in both young and old AD mice, ACAT1 blockage may benefit AD by reducing tauopathy at early stage.


Assuntos
Acetatos/farmacologia , Acetil-CoA C-Acetiltransferase/antagonistas & inibidores , Acetil-CoA C-Acetiltransferase/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Benzimidazóis/farmacologia , Encéfalo/metabolismo , Encéfalo/patologia , Inibidores Enzimáticos/farmacologia , Técnicas de Silenciamento de Genes , Neurônios/metabolismo , Neurônios/fisiologia , Ácidos Sulfônicos/farmacologia , Proteínas tau/metabolismo , Acetamidas , Acetatos/uso terapêutico , Acetil-CoA C-Acetiltransferase/fisiologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Benzimidazóis/uso terapêutico , Células Cultivadas , Colesterol/metabolismo , Ésteres do Colesterol/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Terapia de Alvo Molecular , Fragmentos de Peptídeos/metabolismo , Presenilina-1/metabolismo , Sulfonamidas , Ácidos Sulfônicos/uso terapêutico
6.
FEBS Lett ; 586(21): 3852-7, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23017209

RESUMO

Alternative splicing is involved in functional regulation of the mutagenic enzyme activation-induced cytidine deaminase (AID). However, the molecular basis for AID splicing regulation remains undefined. Using a mini-gene-based screen in HeLa cells, we found that overexpression of RNA binding motif protein 5 (RBM5, or LUCA-15/H37) significantly promoted AID exon 4 skipping by suppressing the splicing of intron 3. The inhibitive effect of RBM5 on intron 3 splicing required a weak 3'-splice site (ss). Indicative of the underlying mechanism, RBM5 interfered with the binding of U2AF65 to the polypyrimidine tract at the 3'-ss in vitro. Our findings thus not only shed lights on the regulatory mechanism of AID exon 4 skipping, but also provide new insights into how RBM5 functions in splicing regulation.


Assuntos
Processamento Alternativo , Proteínas de Ciclo Celular/genética , Citidina Desaminase/genética , Proteínas de Ligação a DNA/genética , Proteínas Nucleares/genética , Precursores de RNA/genética , Proteínas de Ligação a RNA/genética , Ribonucleoproteínas/genética , Proteínas Supressoras de Tumor/genética , Regiões 3' não Traduzidas , Sequência de Bases , Proteínas de Ciclo Celular/metabolismo , Citidina Desaminase/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Éxons , Regulação da Expressão Gênica , Células HeLa , Humanos , Íntrons , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Precursores de RNA/metabolismo , Sítios de Splice de RNA , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/metabolismo , Fator de Processamento U2AF , Proteínas Supressoras de Tumor/metabolismo
7.
FEBS Lett ; 586(7): 977-83, 2012 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-22569250

RESUMO

RNA binding motif protein 5 (RBM5) is a candidate tumor suppressor gene. Recent studies showed that RBM5 functions as an alternative splicing regulator of apoptosis-related genes. Here, we identify DHX15 and PRP19, two spliceosome components, as novel RBM5-interacting partners. We then show that the G-patch domain of RBM5 is indispensable for its ability to interact with DHX15. Strikingly, we find that RBM5 stimulates the helicase activity of DHX15 in a G patch domain-dependent manner in vitro. Helicase activities play critical roles in modulating pre-mRNA splicing. Our findings thus suggest a new mechanism underlying the regulatory roles of RBM5 in pre-mRNA splicing.


Assuntos
Proteínas de Ciclo Celular/metabolismo , RNA Helicases DEAD-box/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Sequência de Aminoácidos , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Células Clonais , RNA Helicases DEAD-box/genética , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Células HEK293 , Células HeLa , Humanos , Imunoprecipitação , Cinética , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Fatores de Processamento de RNA , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Ribonucleoproteína Nuclear Pequena U2/genética , Alinhamento de Sequência , Spliceossomos/enzimologia , Spliceossomos/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Técnicas do Sistema de Duplo-Híbrido
8.
Artigo em Chinês | MEDLINE | ID: mdl-22332521

RESUMO

OBJECTIVE: To investigate the effectiveness of the vacuum sealing drainage (VSD) technique with split middle thickness skin replantation for the treatment of severe skin closed internal degloving injury (CIDI). METHODS: Between July 2008 and April 2011, 16 patients with severe skin CIDI were treated. There were 11 males and 5 females, aged 17-56 years (mean, 28 years). Injury was caused by traffic accident in all cases. The time between injury and operation was 2-8 hours (mean, 5 hours). Peeling skin parts included the upper limb in 3 cases and the lower limb in 13 cases. The range of skin exfoliation was 5%-12% (mean, 7%) of the body surface area with different degree of skin contamination. After thorough debridement, exfoliative skin was made split middle thickness skin graft for in situ replantation, and then VSD was performed. RESULTS: After 7 days of VSD therapy, graft skin survived successfully in 14 cases; partial necrosis of graft skin occurred in 2 cases, and was cured after thorough debridement combined with antibiotics for 7 days. All patients were followed up 6-18 months (mean, 12 months). The appearance of the limb was satisfactory without obvious scar formation, and the blood supply and sensation were normal. The joint function was normal. CONCLUSION: For patients with severe skin CIDI, VSD treatment combined with split middle thickness skin replantation can improve the local blood circulation of the limb, promote replantation skin survival, and shorten healing time of wound. The clinical effectiveness is satisfactory.


Assuntos
Drenagem/métodos , Pele/lesões , Ferimentos e Lesões/cirurgia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Pele , Retalhos Cirúrgicos , Vácuo , Adulto Jovem
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