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1.
BMC Musculoskelet Disord ; 22(1): 588, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174859

RESUMO

BACKGROUND: Here we compared the clinical efficacy of bilateral percutaneous kyphoplasty (PKP) and percutaneous curved kyphoplasty (PCKP) in the treatment of osteoporotic vertebral compression fractures (OVCF). METHODS: Seventy-two patients with single-level thoracolumbar OVCF were randomly divided into 2 groups (36 patients in each) and were subjected to either PCKP or bilateral PKP. The intraoperative fluoroscopy time, total surgical time, bone cement injection volume, bone cement leakage, preoperative and postoperative anterior vertebral height, Cobb angles, visual analog scales (VAS) and oswestry disability index questionnaire (ODI) were recorded. RESULTS: Both groups of patients had a trend towards improvements in VAS and ODI scores 24 h and 6 months after surgery, when compared to preoperative results, despite lack of statistical significance. The total surgical and intraoperative fluoroscopy times and intraoperative bone cement injection volume were significantly decreased in the PCKP group than those in the PKP group. The anterior edge height and Cobb angle of the injured vertebra were similarly improved after operation in both groups. CONCLUSION: PCKP is safer, less invasive and quicker than traditional bilateral PKP despite similar short-term effects for the treatment of OVCF. TRIAL REGISTRATION: ChiCTR, ChiCTR2100042859 . Registered 25 January 2021- Retrospectively registered.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Cimentos Ósseos , Humanos , Estudos Retrospectivos , Resultado do Tratamento
2.
Macromol Rapid Commun ; 41(20): e2000357, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32844547

RESUMO

Janus bottlebrush polymers are a class of special molecular brushes, which have two immiscible side chains on the repeating unit of the backbone. The characteristic architectures of Janus bottlebrush polymers enable unique self-assembly properties and broad applications. Recently, remarkable advances of Janus bottlebrush polymers have been achieved for polymer chemistry and material science. This review summarizes the synthetic strategies of Janus bottlebrush polymers, and highlights the self-assembly applications. Finally, the challenges and opportunities are proposed for the further development.


Assuntos
Polímeros
3.
Macromol Rapid Commun ; 39(8): e1700807, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29450925

RESUMO

Thiol-terminated poly(δ-valerolactone) is directly synthesized via enzymatic 6-mercapto-1-hexanol initiated ring-opening polymerization in both batch and microreactor. By using Candida antartica Lipase B immobilized tubular reactor, narrowly dispersed poly(δ-valerolactone) with higher thiol fidelity is more efficiently prepared in contrast to the batch reactor. Moreover, the integrated enzyme packed tubular reactor system is established to perform the chain extension experiments. Thiol-terminated poly(δ-valerolactone)-block-poly(ε-caprolactone) and poly(ε-caprolactone)-block-poly(δ-valerolactone) are easily prepared by modulating the monomer introduction sequence.


Assuntos
Polímeros/metabolismo , Pironas/metabolismo , Compostos de Sulfidrila/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Polimerização
4.
Chemistry ; 23(39): 9397-9406, 2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28489292

RESUMO

Dual stimuli-responsive nanoparticles capable of fine-tuning drug release to augment therapeutic efficacy have become a promising tool for anticancer drug delivery. However, the rational design of these "smart" nanoparticles for a selective delivery and controlled release of multidrug combinations in cancer cells to achieve synergistic effects remain challenging. Here we report the pH/redox dual responsive nanoparticle FA-DOX-Ind-NP (FA=folic acid, DOX=doxorubicin, Ind=indomethacin, NP=nanoparticle) based on the novel tumor targeting and biodegradable poly(ß-amino ester) polymer, and demonstrate its high ability to enter into cancer cells and release a combination of the anticancer drug doxorubicin and the non-steroidal anti-inflammatory drug indomethacin to achieve synergistic chemo-anti-inflammatory effects and overcome multidrug resistance. This study highlights the great potential of tumor targeting and dual stimuli-responsive nanoparticles for an efficient delivery of multidrug combination to improve the cancer therapeutic efficacy.


Assuntos
Anti-Inflamatórios/química , Antineoplásicos/química , Portadores de Fármacos/química , Nanopartículas/química , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antineoplásicos/metabolismo , Antineoplásicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Doxorrubicina/química , Doxorrubicina/metabolismo , Liberação Controlada de Fármacos , Ácido Fólico , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Indometacina/química , Indometacina/metabolismo , Interleucina-6/metabolismo , Células MCF-7 , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Microscopia Confocal , Polímeros/química , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
5.
Macromol Rapid Commun ; 38(21)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28921703

RESUMO

To address the challenge of metal contamination, a "graft from" approach via organocatalyzed atom transfer radical polymerization (O-ATRP) is developed to synthesize poly(vinylidene fluoride-co-chlorotrifluoroethylene) (P(VDF-co-CTFE)) graft copolymers. N-phenylphenothiazine is utilized as a model organic photoredox catalyst for catalyzing the (co)polymerization of methyl methacrylate (MMA), methacrylate (MA), and n-butyl acrylate (BA). By employing this technique, high temporal control of polymerization and graft content are achieved. A series of P(VDF-co-CTFE)-g-PMMA, P(VDF-co-CTFE)-g-PMA, and P(VDF-co-CTFE)-g-PBA is prepared under mild conditions. The resultant graft copolymer can be used as macroinitiator to re-initiate O-ATRP to synthesize P(VDF-co-CTFE)-g-(PMMA-b-PMA), which might exhibit the potential application as novel dielectric material.


Assuntos
Polimerização , Polivinil/química , Catálise , Cromatografia em Gel , Polivinil/síntese química , Espectroscopia de Prótons por Ressonância Magnética
6.
Plant Mol Biol ; 91(3): 305-18, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26971283

RESUMO

An ethylene response-related factor, GbERF1-like, from Gossypium barbadense cv. '7124' involved in the defence response to Verticillium dahliae was characterized. GbERF1-like transcripts present ubiquitously in various tissues, with higher accumulation in flower organs. GbERF1-like was also responsive to defence-related phytohormones and V. dahliae infection. The downregulation of GbERF1-like increased the susceptibility of cotton plants to V. dahliae infection, while overexpression of this gene improved disease resistance in both cotton and Arabidopsis, coupled with activation of the pathogenesis-related proteins. Further analysis revealed that genes involved in lignin synthesis, such as PAL, C4H, C3H, HCT, CCoAOMT, CCR and F5H, showed higher expression levels in the overexpressing cotton and Arabidopsis lines and lower expression levels in the RNAi cotton lines. The expression levels of these genes increased obviously when the GbERF1-like-overexpressing plants were inoculated with V. dahliae. Meanwhile, significant differences in the content of whole lignin could be found in the stems of transgenic and wild-type plants after inoculation with V. dahliae, as revealed by metabolic and histochemical analysis. More lignin could be detected in GbERF1-like-overexpressing cotton and Arabidopsis but less in GbERF1-like-silencing cotton compared with wild-type plants. The ratio of S and G monomers in GbERF1-like-overexpressing cotton and Arabidopsis increased significantly after infection by V. dahliae. Moreover, our results showed that the promoters of GhHCT1 and AtPAL3 could be transactivated by GbERF1-like in vivo based on yeast one-hybrid assays and dual-luciferase reporter assays. Knockdown of GhHCT1 in GbERF1-like over-expressing cotton decreases resistance to V. dahliae. Collectively, our results suggest that GbERF1-like acts as a positive regulator in lignin synthesis and contributes substantially to resistance to V. dahliae in plants.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Resistência à Doença/fisiologia , Gossypium/fisiologia , Lignina/metabolismo , Proteínas de Plantas/fisiologia , Verticillium , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/fisiologia , Gossypium/genética , Lignina/fisiologia , Transdução de Sinais/fisiologia
7.
Plant Biotechnol J ; 13(4): 514-25, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25418842

RESUMO

Rice is a major food crop with enormous biomass residue for biofuels. As plant cell wall recalcitrance basically decides a costly biomass process, genetic modification of plant cell walls has been regarded as a promising solution. However, due to structural complexity and functional diversity of plant cell walls, it becomes essential to identify the key factors of cell wall modifications that could not much alter plant growth, but cause an enhancement in biomass enzymatic digestibility. To address this issue, we performed systems biology analyses of a total of 36 distinct cell wall mutants of rice. As a result, cellulose crystallinity (CrI) was examined to be the key factor that negatively determines either the biomass enzymatic saccharification upon various chemical pretreatments or the plant lodging resistance, an integrated agronomic trait in plant growth and grain production. Notably, hemicellulosic arabinose (Ara) was detected to be the major factor that negatively affects cellulose CrI probably through its interlinking with ß-1,4-glucans. In addition, lignin and G monomer also exhibited the positive impact on biomass digestion and lodging resistance. Further characterization of two elite mutants, Osfc17 and Osfc30, showing normal plant growth and high biomass enzymatic digestion in situ and in vitro, revealed the multiple GH9B candidate genes for reducing cellulose CrI and XAT genes for increasing hemicellulosic Ara level. Hence, the results have suggested the potential cell wall modifications for enhancing both biomass enzymatic digestibility and plant lodging resistance by synchronically overexpressing GH9B and XAT genes in rice.


Assuntos
Arabinose/metabolismo , Enzimas/metabolismo , Lignina/metabolismo , Mutação , Oryza/metabolismo , Polissacarídeos/metabolismo , Biomassa , Parede Celular/enzimologia , Parede Celular/metabolismo , Genes de Plantas , Oryza/genética
8.
Macromol Rapid Commun ; 36(17): 1539-52, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26248126

RESUMO

Top-down multidimensional mass spectrometry, interfacing electrospray ionization (ESI) with ion mobility mass spectrometry (IM-MS), and energy resolved (gradient) tandem mass spectrometry (gMS(2) ) are employed to characterize the stoichiometries, architectures, and intrinsic stabilities of coordinatively bound supramolecular polymers containing terpyridine functionalized ligands. As a soft ionization method, ESI prevents or minimizes unwanted assembly destruction. The IM dimension affords separation of the supramolecular ions by charge and collision cross-section (a function of size and shape). The mobility separated ions are subsequently identified by their mass-to-charge-ratios and isotope patterns in the orthogonal MS dimension. Finally, the gMS(2) dimension reveals bond breaking proclivities and disintegration pathways of the assemblies. The described methodology does not require high sample purity due to the dispersive nature of the IM and MS steps. Its utility is demonstrated with the comprehensive analysis of bisterpyridine-based metallomacrocycle mixtures and a tristerpyridine based complex with 3-D nanosphere-like architecture.


Assuntos
Polímeros/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Nanoestruturas
9.
Macromol Rapid Commun ; 35(22): 1954-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25283643

RESUMO

Novel amphiphilic polypeptoid-polyester diblock copolymers based on poly(sarcosine) (PSar) and poly(ε-caprolactone) (PCL) are synthesized by a one-pot glovebox-free approach. In this method, sarcosine N-carboxy anhydride (Sar-NCA) is firstly polymerized in the presence of benzylamine under N(2) flow, then the resulting poly(sarcosine) is used in situ as the macro-initiator for the ring-opening polymerization (ROP) of ε-caprolactone using tin(II) octanoate as a catalyst. The degree of poly-merization of each block is controlled by various feed ratios of monomer/initiator. The diblock copolymers with controlled molecular weight and narrow molecular weight distributions (D(M) < 1.2) are characterized by (1)H NMR, (13)C NMR, and size-exclusion chromatography. The self-assembly behavior of PSar-b-PCL in water is investigated by dynamic light scattering (DLS) and transmission electron microscopy. DLS results reveal that the diblock copolymers associate into nanoparticles with average hydrodynamic diameters (D(H)) around 100 nm in water, which may be used as drug delivery carriers.


Assuntos
Peptídeos/síntese química , Poliésteres/síntese química , Tensoativos/síntese química , Luz , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Tamanho da Partícula , Peptídeos/química , Poliésteres/química , Espalhamento de Radiação , Propriedades de Superfície , Tensoativos/química
10.
Phys Chem Chem Phys ; 16(28): 14771-80, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-24922176

RESUMO

Carbon nanotubes (CNTs) were incorporated into a lyotropic liquid crystal (LLC) matrix at room temperature through spontaneous phase separation. The phase separation process occurred in n-dodecyl tetraethylene monoether (C12E4) solutions induced by the hydrophilic polymer, poly(ethylene glycol) (PEG). It was found that the molecular weight of PEG has a significant effect on the CNTs-C12E4 system, which not only influences the phase behavior of the system but also changes the properties of the CNTs-LLC composites. Polarized optical microscopy (POM) images, combined with small-angle X-ray scattering (SAXS) results, indicate that CNTs incorporate within the layers of the lamellar LLCs without destroying the structure of LLCs. Moreover, UV-vis absorption, Raman spectra and rheological measurements were performed to investigate the characteristic properties of the CNTs-LLC composites. This study not only gives a more comprehensive understanding of polymer-induced phase separation, but also expands the potential uses of CNTs-LLC composites in nanotechnology.


Assuntos
Cristais Líquidos/química , Nanotubos de Carbono/química , Polietilenoglicóis/química , Peso Molecular , Tamanho da Partícula , Propriedades de Superfície
11.
Environ Sci Pollut Res Int ; 31(18): 27345-27355, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38512575

RESUMO

Clay liners have been widely used in landfill engineering. However, large-scale clay excavation causes secondary environmental damage. This study investigates the feasibility of replacing clay liners with high-density polyethylene (HDPE) geomembranes with different specifications and parameters. Laboratory interface shear tests between municipal solid waste (MSW) samples of different ages and geomembranes were conducted to study the influence of landfill age on interface shear strength. Finite element method was adopted to compare the long-term stability of landfills with HDPE geomembrane versus clay as intermediate liner. The interfacial shear test results show that the cohesion of MSW increases in a short term and then decreases with landfill age. The internal friction angle exhibits an increasing trend with advancing age, however, the rate of its increment declines with age. The rough accuracy of the film surface can increase the interfacial shear strength between MSW. The simulation results show that, unlike clay-lined landfills, the sliding surface of geomembrane-lined landfills is discontinuous at the lining interface, which can delay the penetration of slip surfaces and block the formation of slip zone in the landfill. In addition, the maximum displacement of landfills with geomembrane is 10% lower than that with clay, and the absolute displacement of slope toe decreases with the increase of roughness at the interface of geomembrane. Compared with clay-lined landfills, the overall stability safety factor increased by 18.5-30%. This study provides references for landfill design and on-site stability evaluation, contributing to enhanced long-term stability.


Assuntos
Eliminação de Resíduos , Instalações de Eliminação de Resíduos , Resíduos Sólidos , Resistência ao Cisalhamento , Polietileno/química , Argila/química
12.
J Plast Surg Hand Surg ; 59: 72-76, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769787

RESUMO

BACKGROUND: The purpose of this article is to introduce a method that combines limited debridement and ReCell® autologous cell regeneration techniques for the treatment of deep second-degree burn wounds. METHOD: A total of 20 patients suffered with deep second-degree burns less than 10% of total body surface area (TBSA) who were admitted to our department, from June 2019 to June 2021, participated in this study. These patients first underwent limited debridement with an electric/pneumatic dermatome, followed by the ReCell® technique for secondary wounds. Routine treatment was applied to prevent scarring after the wound healed. Clinical outcomes were scored using the Vancouver Scar Scale (VSS). RESULTS: All wounds of the patients healed completely. One patient developed an infection in the skin graft area and finally recovered by routine dressing changes. The average healing time was 12 days (range: 10-15 days). The new skin in the treated area was soft and matched the colour of the surrounding normal skin and the VSS score ranged from 3~5 for each patient. Of the 20 patients, 19 were very satisfied and 1 was satisfied. CONCLUSIONS: This article reports a useful treatment method that combines electric dermatome-dependent limited debridement and the ReCell® technique for the treatment of deep second-degree burn wounds. It is a feasible and effective strategy that is easy to implement and minimally invasive, and it is associated with a short healing time, mild scar formation and little damage to the donor skin area.


Assuntos
Queimaduras , Desbridamento , Transplante de Pele , Humanos , Queimaduras/cirurgia , Queimaduras/terapia , Desbridamento/métodos , Masculino , Adulto , Feminino , Transplante de Pele/métodos , Pessoa de Meia-Idade , Adulto Jovem , Cicatrização/fisiologia , Cicatriz , Adolescente , Poliésteres
13.
Int J Nanomedicine ; 19: 859-881, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38293610

RESUMO

The various tissue damages are a severe problem to human health. The limited human tissue regenerate ability requires suitable biomaterials to help damage tissue repair and regeneration. Therefore, many researchers devoted themselves to exploring biomaterials suitable for tissue repair and regeneration. Polydopamine (PDA) as a natural and multifunctional material which is inspired by mussel has been widely applied in different biomaterials. The excellent properties of PDA, such as strong adhesion, photothermal and high drug-loaded capacity, seem to be born for tissue repair and regeneration. Furthermore, PDA combined with different materials can exert unexpected effects. Thus, to inspire researchers, this review summarizes the recent and representative development of PDA biomaterials in tissue repair and regeneration. This article focuses on why apply PDA in these biomaterials and what PDA can do in different tissue injuries.


Assuntos
Materiais Biocompatíveis , Indóis , Polímeros , Humanos , Materiais Biocompatíveis/farmacologia , Cicatrização , Regeneração
14.
Mar Pollut Bull ; 199: 115972, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154170

RESUMO

To investigate the spatial distribution and source of plutonium isotopes in the Beibu Gulf, surface sediments were collected and analyzed using sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). The activities of 239+240Pu in surface sediments ranged from 0.012 to 0.451 mBq/g (mean: 0.171 ± 0.138 mBq/g, n = 36), indicating a decreasing trend in a counterclockwise direction from the southern bay mouth. The counterclockwise decreasing trend in the south of the bay mouth is similar to the current in the Beibu Gulf. The 240Pu/239Pu atom ratios in surface sediments ranged from 0.156 to 0.283 (mean: 0.236 ± 0.031, n = 36), slightly higher than that of the global fallout value of 0.18. This suggests that the Pu in the Beibu Gulf was a combination of global fallout and Pacific Proving Ground (PPG). The average contribution of the plutonium (Pu) derived from the PPG in the sediment was estimated to be 52 % ± 24 %.


Assuntos
Plutônio , Monitoramento de Radiação , Cinza Radioativa , Poluentes Radioativos da Água , Sedimentos Geológicos/química , Plutônio/análise , Poluentes Radioativos da Água/análise , China , Cinza Radioativa/análise
15.
Biochem Biophys Res Commun ; 430(3): 1151-6, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23246835

RESUMO

4-Coumarate:coenzyme A ligase (4CL) catalyzes the conversion of hydroxycinnamates into corresponding CoA esters for biosynthesis of flavonoids and lignin. In this study, five members of the 4CL gene family from rice were cloned and analyzed. Recombinant 4CL data revealed that 4-coumaric acid and ferulic acid were the two main substrates of 4CL (Os4CL1/3/4/5) for monolignol biosynthesis in rice. Os4CL2 was specifically expressed in the anther and was strongly activated by UV irradiation, suggesting its potential involvement in flavonoid formation. Moreover, bioinformatics analysis showed that the existence of valine residue at the substrate-binding pocket may mainly affect rice 4CL activities toward sinapic acid.


Assuntos
Coenzima A Ligases/metabolismo , Flavonoides/biossíntese , Lignina/biossíntese , Oryza/enzimologia , Estresse Fisiológico/genética , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Coenzima A Ligases/química , Coenzima A Ligases/genética , Regulação da Expressão Gênica de Plantas , Cinética , Dados de Sequência Molecular , Oryza/genética
16.
Biomacromolecules ; 14(9): 3304-13, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-23931528

RESUMO

Hydroxyapatite (HA)-coated surfaces are used widely as stationary phase for protein and enzyme purification, coatings for dental and orthopedic implants, and composite materials for tissue engineering substrates. More advanced applications are envisioned, but progress has been slowed by the limited ability to controllably functionalize the surface of HA with biomolecules in a translationally relevant manner. Herein we report the synthesis and characterization of a series of multivalent, HA-binding peptide bioconjugates with variable valency and tether length which afford the ability to precisely tune the desired binding behavior. The respective binding affinities of the multivalent constructs to HA surface were characterized by quartz crystal microbalance with dissipation monitoring (QCM-D) techniques, and the relationship between dendron structure and binding affinity was revealed. Tetravalent constructs of HA-binding peptides show a 100-fold enhancement in binding affinity compared to HA-binding peptide sequences reported previously. Both biotin and bone morphogenic protein-2 (BMP-2) derivative peptide were successfully linked to the focal point as initial demonstrations.


Assuntos
Dendrímeros/química , Hidroxiapatitas/química , Adsorção , Sequência de Aminoácidos , Biotina/química , Proteína Morfogenética Óssea 2/química , Materiais Revestidos Biocompatíveis/química , Reação de Cicloadição , Proteínas Imobilizadas/química , Conformação Molecular , Dados de Sequência Molecular , Peptídeos/química , Ligação Proteica , Técnicas de Microbalança de Cristal de Quartzo , Propriedades de Superfície , Termodinâmica , Engenharia Tecidual
17.
Biomacromolecules ; 14(10): 3749-58, 2013 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-24050500

RESUMO

We demonstrate the formation of polyethylene glycol (PEG) based hydrogels via oxime ligation and the photoinitiated thiol-ene 3D patterning of peptides within the hydrogel matrix postgelation. The gelation process and final mechanical strength of the hydrogels can be tuned using pH and the catalyst concentration. The time scale to reach the gel point and complete gelation can be shortened from hours to seconds using both pH and aniline catalyst, which facilitates the tuning of the storage modulus from 0.3 to over 15 kPa. Azide- and alkene-functionalized hydrogels were also synthesized, and we have shown the post gelation "click"-type Huisgen 1,3 cycloaddition and thiolene-based radical reactions for spatially defined peptide incorporation. These materials are the initial demonstration for translationally relevant hydrogel materials that possess tunable mechanical regimes attractive to soft tissue engineering and possess atom neutral chemistries attractive for post gelation patterning in the presence or absence of cells.


Assuntos
Géis/síntese química , Hidrogéis/química , Oximas/química , Peptídeos/química , Géis/química , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Tamanho da Partícula , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Compostos de Sulfidrila/química , Propriedades de Superfície
18.
Carbohydr Polym ; 301(Pt B): 120321, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36446489

RESUMO

To pursue highly functional ecologically friendly materials, functionalized cellulose has gained increasing number of research interests within the last decades. Compared with other cellulose modification approaches, surface modification of cellulose via photo-induced click reaction is a particular attractive cellulose modification strategy as it integrates the advantages of photochemistry, click reaction and surface modification. High efficiency, quantitative conversion and spatial temporal control are achieved. The physical and chemical properties of various cellulose surfaces are also effectively regulated by using this strategy, which significantly expands their applications. In this mini-review, we summarized the recent progress in cellulose surface modification via photo-induced click reactions. The principles and the merits of photo-induced thiol-X and cycloaddition reactions were compared and highlighted. Photo-induced thiol-ene reaction, thiol-yne reaction, tetrazole-ene cycloaddition, Diels-Alder cycloaddition, and azide-alkyne cycloaddition applied in modification of various cellulose surfaces were introduced in order. At last, the challenges and outlook of photo-induced click reaction in cellulose surface modification were discussed. We hope this review will provide insights into photo-induced click chemistry, cellulose surface modification and novel sustainable materials.


Assuntos
Celulose , Química Click , Reação de Cicloadição , Azidas , Compostos de Sulfidrila
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 289: 122182, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36512967

RESUMO

To ensure the long-term sustainable development of nuclear energy as well as the prevention and control of uranium pollution, new materials that can simultaneously detect and separate uranium are still urgently needed. Herein, a new fluorescent covalent organic polymer (COP), namely HT-COP-AO, was synthesized andemployed as both the fluorescent probe and absorbent for simultaneous uranium detection and separationconsidering its excellent fluorescence property and strong uranium coordination ability. The results showed that the fluorescence of HT-COP-AO was quickly quenched by uranium within 2 min, and the limit of detection was 0.23 µM (3σ/K). Further studies implied that uranium was coordinated with the amidoxime groups of HT-COP-AO through U-N and O = U = O bonds, which resulted in electron transfer from uranium to HT-COP-AO and quenching the fluorescence of HT-COP-AO consequently. Meanwhile, HT-COP-AO exhibited excellent absorption ability towards uranium, and the maximum absorption capacity (qmax = 401.3 mg/g) was higher than most reported amidoxime modified materials. The HT-COP-AO also showed high selectivity for both uranium detection and separation which makes it a great promising for uranium monitoring in real water samples.


Assuntos
Urânio , Corantes Fluorescentes , Transporte de Elétrons , Polímeros
20.
Nutrients ; 15(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37836525

RESUMO

Dyslipidemia, a condition implying high cardiovascular risks, has been widely studied on its potential nutrition interventions, including functional foods. This study aims to examine the effect of nattokinase monascus supplements (NMSs) on cardiovascular biomarkers and carotid intima-media thickness (CIMT) in patients with dyslipidemia. A total of 113 eligible subjects were randomly assigned to receive either NMSs or a placebo (55 and 58, respectively). After a 120-day intervention, there were significant mean absolute changes in total cholesterol (TC), low-density cholesterol (LDL-C), non-high-density cholesterol (non-HDL-C), and low-density cholesterol to high-density cholesterol ratio (LDL-C to HDL-C ratio), with values of -0.52 (95% CI: -0.51 to -0.54) mmol/L, -0.43 (95% CI: -0.45 to -0.41) mmol/L, -0.52 (95% CI: -0.52 to -0.52) mmol/L, and -0.29 (95% CI: -0.30 to -0.28) mmol/L, respectively, between the two groups. However, no significant differences were found in triglycerides (TGs), high-density cholesterol (HDL-C), and CIMT. Furthermore, the results for lipids and CIMT remained essentially unchanged after adjusting for various confounding factors using the analysis of covariance model. There were no significant differences in coagulation, liver function, renal function, or other indicators. No intervention-related adverse events, such as mouth ulcers, drooling, and stomach pain, were reported. The study results demonstrate that NMSs can ameliorate lipid levels (TC, LDL-C, non-HDL-C, and the LDL-C to HDL-C ratio) without the occurrence of adverse events. However, it did not significantly affect serum TG, HDL-C, and CIMT.


Assuntos
Dislipidemias , Hipercolesterolemia , Hiperlipidemias , Monascus , Humanos , LDL-Colesterol , HDL-Colesterol , Espessura Intima-Media Carotídea , Hipercolesterolemia/epidemiologia , Triglicerídeos , Dislipidemias/tratamento farmacológico , Método Duplo-Cego
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