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1.
Sensors (Basel) ; 24(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38676245

RESUMO

Fingerprint recognition systems have achieved widespread integration into various technological devices, including cell phones, computers, door locks, and time attendance machines. Nevertheless, individuals with worn fingerprints encounter challenges when attempting to unlock original fingerprint systems, which results in disruptions to their daily activities. This study explores two distinct methods for fingerprint backup: traditional fingerprint impression and 3D printing technologies. Unlocking tests were conducted on commonly available optical fingerprint lock-equipped cell phones to assess the efficacy of these methods, particularly in unlocking with worn fingerprints. The research findings indicated that the traditional fingerprint impression method exhibited high fidelity in reproducing fingerprint patterns, achieving an impressive unlocking success rate of 97.8% for imprinting unworn fingerprints. However, when dealing with worn fingerprints, the traditional fingerprint impression technique showed a reduced unlocking success rate, progressively decreasing with increasing degrees of finger wear. In contrast, 3D-printed backup fingerprints, with image processing and optimization of ridge height, mitigated the impact of fingerprint wear on the unlocking capability, resulting in an unlocking success rate of 84.4% or higher. Thus, the utilization of 3D printing technology proves advantageous for individuals with severely worn or incomplete fingerprints, providing a viable solution for unforeseen circumstances.


Assuntos
Dermatoglifia , Impressão Tridimensional , Humanos , Dedos/fisiologia , Processamento de Imagem Assistida por Computador/métodos
2.
Bioorg Med Chem Lett ; 105: 129752, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38631541

RESUMO

The misfolding and aggregation of α-Syn play a pivotal role in connecting diverse pathological pathways in Parkinson's disease (PD). Preserving α-Syn proteostasis and functionality by inhibiting its aggregation or disaggregating existing aggregates using suitable inhibitors represents a promising strategy for PD prevention and treatment. In this study, a series of benzothiazole-polyphenol hybrids was designed and synthesized. Three identified compounds exhibited notable inhibitory activities against α-Syn aggregation in vitro, with IC50 values in the low micromolar range. These inhibitors demonstrated sustained inhibitory effects throughout the entire aggregation process, stabilizing α-Syn proteostasis conformation. Moreover, the compounds effectively disintegrated preformed α-Syn oligomers and fibers, potentially by binding to specific domains within the fibers, inducing fibril instability, collapse, and ultimately resulting in smaller-sized aggregates and monomers. These findings offer valuable insights into the therapeutic potential of polyphenol hybrids with 2-conjugated benzothiazole targeting α-Syn aggregation in the treatment of PD.


Assuntos
Benzotiazóis , Polifenóis , Agregados Proteicos , alfa-Sinucleína , Benzotiazóis/química , Benzotiazóis/farmacologia , Benzotiazóis/síntese química , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/metabolismo , Polifenóis/química , Polifenóis/farmacologia , Polifenóis/síntese química , Humanos , Agregados Proteicos/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo
3.
Eur J Med Chem ; 268: 116198, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368711

RESUMO

α-Syn fibers, the primary cause and central element of Lewy bodies (LB), play a pivotal role in the development of Parkinson's disease (PD). This research aims to identify more potent inhibitors of α-Syn aggregation. A series of N-aryl-3-aryl-pyrazole-5-carboxamide derivatives were designed and synthesized for this purpose. Among them, four candidate compounds, combining pyrazole and polyphenol blocks, were identified through screening, demonstrating good inhibitory effects with IC50 values in the low micromolar range (1.25-4.29 µM). Two candidates exhibited high permeability through the blood-brain barrier. Mechanistic studies using various methods revealed that the candidates preferentially bind to the aggregation-prone domains-proNAC or NAC domains of α-Syn. This binding hinders the conformational transition from random coil/α-helix to ß-sheet, preserving α-Syn proteostasis. As a result, it interferes with α-Syn nuclei formation, prolongs the lag phase, decelerates the elongation phase, and ultimately impedes the formation of α-Syn fibrils. Additionally, the candidates demonstrated promising results in the disaggregation of preformed α-Syn fibers, potentially by binding to specific sites near the ß-sheet domain within fibers. This reduces fiber stability, causing rapid collapse and yielding smaller aggregates and monomers. Crucially, the candidate compounds exhibited significant inhibitory efficacy against α-Syn aggregation within nerve cells with low cytotoxicity. This resulted in a notable inhibition of the formation of LB-like α-Syn inclusions. These compounds show considerable promise as potential therapeutic agents for the prevention and treatment of PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Neurônios/metabolismo , Transporte Biológico
4.
Bioorg Med Chem Lett ; 99: 129618, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38219887

RESUMO

This study focuses on the discovery of new potential drugs for treating PD by targeting the aggregation of α-Syn. A series of hybrids combining Coumarin and phenolic acid were designed and synthesized. Four particularly promising compounds were identified, showing strong inhibitory effects with IC50 values ranging from low micromolar to submicromolar concentrations, as low as 0.63 µM. These compounds exhibited a higher binding affinity to α-Syn residues and effectively hindered the entire aggregation process, maintaining the proteostasis conformation of α-Syn and preventing the formation of ß-sheet aggregates. This approach holds significant promise for PD prevention. Additionally, these candidate compounds demonstrated the ability to break down preformed α-Syn oligomers and fibrils, resulting in the formation of smaller aggregates and monomers. Moreover, the candidate compounds showed impressive effectiveness in inhibiting α-Syn aggregation within nerve cells, thereby reducing the likelihood of α-Syn inclusion formation resembling Lewy bodies, which highlights their potential for treating PD.


Assuntos
Neurônios , alfa-Sinucleína , alfa-Sinucleína/metabolismo , Ligação Proteica , Neurônios/metabolismo , Cumarínicos/farmacologia
5.
Bioorg Med Chem Lett ; 97: 129564, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38000482

RESUMO

The aggregation of α-Syn is a pivotal mechanism in Parkinson's disease (PD). Effectively maintaining α-Syn proteostasis involves both inhibiting its aggregation and promoting disaggregation. In this study, we developed a series of aromatic amide derivatives based on Rhein. Two of these compounds, 4,5-dihydroxy-N-(3-hydroxyphenyl)-9,10-dioxo-9,10-dihydroanthracene-2-carboxamide (a5) and 4,5-dihydroxy-N-(2-hydroxy-4-chlorophenyl)-9,10-dioxo-9,10-dihydroanthracene-2-carboxamide (a8), exhibited good binding affinities to α-Syn residues, demonstrating promising inhibitory activity against α-Syn aggregation in vitro, with low IC50 values (1.35 and 1.08 µM, respectivly). These inhibitors acted throughout the entire aggregation process by stabilizing α-Syn's conformation and preventing the formation of ß-sheet aggregates. They also effectively disassembled preformed α-Syn oligomers and fibrils. Preliminary mechanistic insights indicated that they bound to the specific domain within fibrils, inducing fibril instability, collapse, and the formation of smaller aggregates and monomeric α-Syn units. This research underscores the therapeutic potential of Rhein's aromatic amides in targeting α-Syn aggregation for PD treatment and suggests broader applications in managing and preventing neurodegenerative diseases.


Assuntos
Antracenos , Doença de Parkinson , Humanos , alfa-Sinucleína , Antraquinonas/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/prevenção & controle , Doença de Parkinson/metabolismo , Antracenos/química , Antracenos/farmacologia
6.
Bioorg Med Chem ; 96: 117529, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37976808

RESUMO

This study focuses on the misfolding and aggregation of α-Syn as a central mechanism linking various pathological processes in PD. Maintaining α-Syn proteostasis through suitable inhibitors emerges as an effective approach to prevent PD. A more efficient strategy for PD treatment involves disintegrating neurotoxic oligomers and fibrils into normal functional α-Syn using inhibitors. To this end, a series of 4-arylidene curcumin derivatives were synthesized with a sheet-like conjugated skeleton and higher binding energies with α-Syn residues. Among these derivatives, three candidate compounds exhibited promising α-Syn aggregation inhibitory activities in vitro, with IC50 values as low as 0.61 µM. The inhibitory action extended throughout the entire aggregation process, stabilizing α-Syn proteostasis conformation and preventing ß-sheets aggregation. Furthermore, the candidate compounds demonstrated effective disintegration capabilities against preformed α-Syn oligomers and fibrils. Initial mechanistic investigations indicated that the inhibitors may bind to a specific domain within the fibril, inducing fibril instability and subsequent collapse. This process resulted in the formation of a complex system of aggregates with smaller sizes and monomers. Overall, these findings provide valuable insights into the potential of 4-arylidene curcumin derivatives as therapeutic agents for targeting α-Syn aggregation in PD treatment.


Assuntos
Curcumina , alfa-Sinucleína , alfa-Sinucleína/metabolismo , Curcumina/farmacologia , Ligação Proteica , Amiloide/metabolismo , Agregados Proteicos
7.
Food Funct ; 14(24): 10991-11004, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38019161

RESUMO

To produce peptides with high dipeptidyl peptidase IV (DPP-IV) inhibitory activity, neutrase was selected from five proteases (trypsin, neutrase, pepsin, alcalase and flavor protease) with the highest degree of hydrolysis (DH) (18.23 ± 1.08%) and DPP-IV inhibitory rate (53.35 ± 4.02%) to produce protein hydrolysate (NPH) from the dark muscles of skipjack tuna (Katsuwonus pelamis). Then, NPH-1 was isolated from NPH by gel permeation chromatography and found to possess the highest DPP-IV inhibitory rate (65.12 ± 7.94% at 0.5 mg ml-1) in the separated components (including NPH-1, NPH-2, NPH-3 and NPH-4). Subsequently, the available prediction models of tripeptides and tetrapeptides with the DPP-IV inhibitory rate were established using an artificial neural network (ANN). The RMSE (0.56 and 0.33 for the model established through collected tripeptides and tetrapeptides, respectively) and R2 (0.95 and 0.99 for the model established through collected tripeptides and tetrapeptides, respectively) of the ANN model's parameters were within acceptable limits, indicating that this model is available. Next, the ANN model was applied to predict tripeptides and tetrapeptides from the hydrolysate of skipjack tuna dark muscles, and five peptides (Ala-Pro-Pro (APP), Pro-Pro-Pro (PPP), Asp-Pro-Leu-Leu (DPLL), Glu-Ala-Val-Pro (EAVP) and Glu-Ala-Iie-Pro (EAIP)) possessing a noticeable DPP-IV inhibitory rate (with DPP-IV IC50 values of 42.46 ± 5.02, 37.71 ± 9.17, 58.85 ± 14.42, 49.94 ± 6.69 and 57.15 ± 6.13 µM, respectively) were screened from the protein hydrolysate. The above five peptides were proved to effectively promote glucose consumption in the insulin resistant-HepG2 (IR-HepG2) cell model considering that the glucose consumption rates of APP, PPP, DPLL, EAVP and EAIP treatment groups are all more than twice that of the dexamethasone group. Accordingly, mechanistic studies showed that these peptides interacted with PI3K/AKT and AMPK signaling pathways and promoted the phosphorylation of PI3K p110, AKT and AMPK (the protein expressions of PI3K p110, p-AKT and p-AMPK in APP, PPP, DPLL, EAVP and EAIP treatment groups are 1.64-2.22 fold compared with that in the dexamethasone group), thereby enhancing glucose uptake and further alleviating insulin resistance. These findings demonstrated that skipjack tuna dark muscle is a potential DPP-IV inhibitory peptide source, and five DPP-IV inhibitory peptides from its hydrolysate may exert potent anti-diabetic activity. In comparison, PPP may be the most potential active ingredient for healthy food against type 2 diabetes mellitus in the five screened peptides considering synthetically the DPP-IV inhibitory rate, bioavailability and synthesis cost.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Animais , Humanos , Atum/metabolismo , Hidrolisados de Proteína/química , Insulina/metabolismo , Dipeptidil Peptidase 4/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Células Hep G2 , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peptídeos/química , Peptídeo Hidrolases/química , Músculos/metabolismo , Glucose/metabolismo , Dexametasona , Inibidores da Dipeptidil Peptidase IV/química
8.
Foods ; 12(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37761111

RESUMO

This study was conducted to prepare calcium chelate of low-molecular-weight tuna bone collagen peptides (TBCPLMW) with a high chelation rate and to identify its structural characteristics and stability. The optimum conditions for calcium chelation of TBCPLMW (TBCPLMW-Ca) were determined through single-factor experiments and response surface methodology, and the calcium-chelating capacity reached over 90% under the optimal conditions. The amino acid compositions implied that Asp and Glu played important roles in the formation of TBCPLMW-Ca. Structural characterizations determined via spectroscopic analyses revealed that functional groups such as -COO-, N-H, C=O, and C-O were involved in forming TBCPLMW-Ca. The particle size distributions and scanning electron microscopy results revealed that folding and aggregation of peptides were found in the chelate. Stability studies showed that TBCPLMW-Ca was relatively stable under thermal processing and more pronounced changes have been observed in simulated gastric digestion, presumably the acidic environment was the main factor causing the dissociation of the TBCPLMW-Ca. The results of this study provide a scientific basis for the preparation of a novel calcium supplement and is beneficial for comprehensive utilization of tuna bones.

9.
J Contemp Brachytherapy ; 15(2): 134-140, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37215613

RESUMO

Purpose: The purpose of this study was to investigate the precision of deep learning (DL)-based auto-reconstruction in localizing interstitial needles in post-operative cervical cancer brachytherapy (BT) using three-dimensional (3D) computed tomography (CT) images. Material and methods: A convolutional neural network (CNN) was developed and presented for automatic reconstruction of interstitial needles. Data of 70 post-operative cervical cancer patients who received CT-based BT were used to train and test this DL model. All patients were treated with three metallic needles. Dice similarity coefficient (DSC), 95% Hausdorff distance (95% HD), and Jaccard coefficient (JC) were applied to evaluate the geometric accuracy of auto-reconstruction for each needle. Dose-volume indexes (DVI) between manual and automatic methods were used to analyze the dosimetric difference. Correlation between geometric metrics and dosimetric difference was evaluated using Spearman correlation analysis. Results: The mean DSC values of DL-based model were 0.88, 0.89, and 0.90 for three metallic needles. Wilcoxon signed-rank test indicated no significant dosimetric differences in all BT planning structures between manual and automatic reconstruction methods (p > 0.05). Spearman correlation analysis demonstrated weak link between geometric metrics and dosimetry differences. Conclusions: DL-based reconstruction method can be used to precisely localize the interstitial needles in 3D-CT images. The proposed automatic approach could improve the consistency of treatment planning for post-operative cervical cancer brachytherapy.

10.
Food Chem ; 421: 136201, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37105117

RESUMO

Natural essential oils (EOs), especially those combining different individual EOs (also termed composite EOs) with enhanced performance, are becoming healthy, market-sought food preservatives/additives. This study aims to provide insights into the challenge regarding EOs processing due to their low solubility and the elusive mechanism under the enhanced bio-reactivity of composite EOs. A unique oil/water interacting network was created by phase-inversion processing, which enhances EO solubilization and emulsification to form composite EO formulations (EOFs) containing ordinary cinnamon, oregano and clove EOs. These EOFs mainly contained cinnamaldehyde, carvacrol and eugenol and exhibited excellent post-storage stability. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability of EOFs (at 15.880 µL/mL) was > 88%, and the Ferric reducing antioxidant power (FRAP) was 1.8 mM FeSO4·7H2O. The minimum inhibitory concentration (MIC) of EOFs against E. coli and S. aureus was ∼7.940 µL/mL. The EOFs could cause quick deterioration of bacterial structures, demonstrating high efficacy in bacteria-killing and anti-biofilm formation.


Assuntos
Óleos Voláteis , Origanum , Syzygium , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Origanum/química , Cinnamomum zeylanicum/química , Staphylococcus aureus , Emulsões , Escherichia coli , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
11.
Front Med (Lausanne) ; 10: 1031713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020677

RESUMO

Objective: To identify author collaborations and impact; participating countries, institutions, and journals; evaluate the knowledge base; and analyze research hotspots and frontiers in teaching reforms in physiology. Methods: Articles and reviews related to teaching reforms in physiology published between January 1, 2012, and December 31, 2021, were obtained from the Web of Science Core Collection. Two Scientometric software applications (CiteSpace 5.7 and VOSviewer 1.6.15) were used to perform bibliometric and knowledge-map analysis, generate network maps, and identify research trends and top keywords, authors, co-cited authors, institutions, countries, journals, and references. Results: The search identified a total of 2,882 papers in 466 academic journals by 13,895 authors from 4,072 organizations in 67 countries/regions. Physiology teaching reform-related publications increased rapidly over time. Arango-Lasprilla and Rivera published the most papers, while Moseley had the most co-citations. Active collaborations among physiology researchers were noted. Advances in Physiology Education published the most papers on physiology teaching reforms and was also the top co-cited journal in the Medicine/Medical/Clinical, Psychology/Education/Health, and Neurology/Sports/Ophthalmology fields. The United States and University of California published the most physiology teaching publications in the search criteria. Ten references (research articles and reviews) on mechanisms and diseases were identified as the knowledge base. The mainstream research directions were education, Alzheimer's disease, performance, physiology, and risk factors. Mental health and emotion regulation are increasing in significance and may become new hotspots. The research trend to move from the field of pain pathogenesis to the field of neuropsychiatry has become increasingly clear. This tendency away from peripheral system-based disorders to central system-based orders is inextricably linked to further developments in physiological understanding of the brain. Conclusion: This study analyzed the research hot spots and frontiers of teaching reforms on in physiology using bibliometric and visual methods. Based on the results, rehabilitation, neurosciences, and infectious disease are hot topics in physiology. In particular, the pathogenesis of neurological diseases, treatment strategies, and technology updates have gradually become research hotspots. We predict that this trend is closely related to the implementation of brain research programs in various countries. These findings provide helpful references for scholars focusing on physiology education.

12.
Carbohydr Polym ; 305: 120550, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36737199

RESUMO

Inulin is a prebiotic carbohydrate widely used in food industry due to its health benefits and unique rheological properties. For the first time, this study explores the potential of natural inulin as a sustainable food additive to enhance surimi gel characteristics, specifically focusing on understanding its molecular weight effects. The good solubility of inulin facilitates the conversion of α-helix to other secondary conformations which are favorable for protein denaturation and aggregation during gelation. Moreover, the abundant -OH groups at the surface of inulin can boost the chemical forces within surimi proteins to reinforce the gel network. Compared to short-chain inulin, long-chain inulin can alleviate proteolysis, enhance hydrophobic interactions and intertwine with myosin molecules, thereby reinforcing the gel network. A more viscous long-chain inulin solution formed within surimi gels fills the space between aggregated proteins and facilitates the lock of water molecules, improving the water-holding capacity (WHC). Thus, an addition of 12 % long-chain inulin leads to an enhanced hardness of surimi gel from 943 to 1593 and improved WHC from 72 % to 85 %. A new inulin-myosin interaction mechanism model is also proposed to provide useful guidelines for surimi processing and expanding the application of inulin within the food industries.


Assuntos
Produtos Pesqueiros , Inulina , Peso Molecular , Produtos Pesqueiros/análise , Géis/química , Manipulação de Alimentos , Miosinas , Água
13.
Photochem Photobiol ; 99(5): 1318-1331, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36588480

RESUMO

Exposure of ultraviolet B (UVB) radiation is the main factor from the environment to cause skin photoaging. Lactobacillus rhamnosus ATCC 7469, is a probiotic strain with a good track record for enhancing human health. The present study conducted the impacts of heat-killed L. rhamnosus ATCC 7469 (RL) on photoaging in vitro using mouse skin fibroblast (MSF) cells and human epidermal melanocytes (HEM) exposed to UVB. The results showed that (1) RL-protected UVB-induced cytotoxicity relating to absorb UVB and reduce DNA damage. (2) RL exerted the antiwrinkle impact involved in two aspects. Firstly, RL downregulated MMP-1, 2, 3 expressions associating with MAPK signaling, resulting in the increased the protein expression of COL1A1, further booting type I collagen abundant thereby promoting the antiwrinkle impact in MSF cells. Secondly, RL reduced ROS content, further decreasing oxidative damage relating to Nrf2/Sirt3/SOD2 signaling, thereby promoting the antiwrinkle impact in MSF cells. (3) RL suppressed tyrosinase and TYRP-2 activity and/or levels associating with PKA/CREB/MITF signaling, thereby promoting antimelanogenesis impact in HEM cells. In conclusion, our findings suggest that RL could reduce photoaging caused by UVB via antiwrinkle and antimelanogenesis properties and may be a potential antiphotoaging beneficial component, which is applied in the cosmetic industry.


Assuntos
Lacticaseibacillus rhamnosus , Envelhecimento da Pele , Animais , Camundongos , Humanos , Temperatura Alta , Pele/metabolismo , Epiderme , Raios Ultravioleta , Fibroblastos/metabolismo
14.
Food Chem ; 407: 135157, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36529012

RESUMO

Surimi products have unsatisfactory gel properties. Hence, this study evaluates the effect of collagen-adding on surimi gel properties and provides the first observation results regarding collagen type influence. With higher water solubility and more charged amino acids than type II, collagen type I intertwines with surimi myofibrillar proteins better to induce higher exposure of protein functional domains, more sufficient conformational changes of myosin and greater formation of chemical forces among proteins. These enhancements accelerate the gelation rate, leading to a well-stabilized surimi gel. The collagen I-containing surimi gels show more compact structures with uniformly distributed smaller pores than those containing collagen II, thereby providing the final products with higher water holding capacity and better textural profiles. As such, the surimi gel fortification performance of collagen I and the well-elucidated collagen-myofibrillar protein interaction mechanism will guide the further exploitation of collagen as an effective additive in the food industry.


Assuntos
Proteínas de Peixes , Manipulação de Alimentos , Manipulação de Alimentos/métodos , Proteínas de Peixes/química , Produtos Pesqueiros/análise , Géis/química , Colágeno , Água
15.
Int J Mol Sci ; 23(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36555167

RESUMO

Selenium nanoparticles have attracted extensive attention due to their good bioavailability and activity. In the present study, a new form of selenium nanoparticle (Low molecular weight chitosan selenium nanoparticles (LCS-SeNPs)) were synthesized in a system of sodium selenite and acetic acid. The size, element state, morphology and elementary composition of LCS-SeNPs were characterized by using various spectroscopic and microscopic measurements. The protection of LCS-SeNPs against dextran sulfate sodium (DSS)-induced intestinal barrier dysfunction and the inherent mechanisms of this process were investigated. The results showed that LCS-SeNPs, with an average diameter of 198 nm, zero-valent and orange-red relatively uniform spherical particles were prepared. LCS-SeNPs were mainly composed of C, N, O and Se elements, of which Se accounted for 39.03% of the four elements C, N, O and Se. LCS-SeNPs reduced colon injury and inflammation symptoms and improved intestinal barrier dysfunction. LCS-SeNPs significantly reduced serum and colonic inflammatory cytokines TNF-α and IL-6 levels. Moreover, LCS-SeNPs remarkably increased antioxidant enzyme GSH-Px levels in serum and colonic tissue. Further studies on inflammatory pathways showed that LCS-SeNPs alleviated DSS-induced colitis through the NF-κB signaling pathway, and relieved inflammatory associated oxidative stress through the Nrf2 signaling pathway. Our findings suggested that LCS-SeNPs are a promising selenium species with potential applications in the treatment of oxidative stress related inflammatory intestinal diseases.


Assuntos
Quitosana , Colite Ulcerativa , Nanopartículas , Selênio , Animais , Camundongos , Selênio/farmacologia , Selênio/química , Quitosana/química , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Peso Molecular , Nanopartículas/química
16.
Polymers (Basel) ; 14(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36235973

RESUMO

Cellulose is the most abundant biopolymer on Earth, which is synthesized by plants, bacteria, and animals, with source-dependent properties. Cellulose containing ß-1,4-linked D-glucoses further assembles into hierarchical structures in microfibrils, which can be processed to nanocellulose with length or width in the nanoscale after a variety of pretreatments including enzymatic hydrolysis, TEMPO-oxidation, and carboxymethylation. Nanocellulose can be mainly categorized into cellulose nanocrystal (CNC) produced by acid hydrolysis, cellulose nanofibrils (CNF) prepared by refining, homogenization, microfluidization, sonification, ball milling, and the aqueous counter collision (ACC) method, and bacterial cellulose (BC) biosynthesized by the Acetobacter species. Due to nontoxicity, good biodegradability and biocompatibility, high aspect ratio, low thermal expansion coefficient, excellent mechanical strength, and unique optical properties, nanocellulose is utilized to develop various cellulose nanocomposites through solution casting, Layer-by-Layer (LBL) assembly, extrusion, coating, gel-forming, spray drying, electrostatic spinning, adsorption, nanoemulsion, and other techniques, and has been widely used as food packaging material with excellent barrier and mechanical properties, antibacterial activity, and stimuli-responsive performance to improve the food quality and shelf life. Under the driving force of the increasing green food packaging market, nanocellulose production has gradually developed from lab-scale to pilot- or even industrial-scale, mainly in Europe, Africa, and Asia, though developing cost-effective preparation techniques and precisely tuning the physicochemical properties are key to the commercialization. We expect this review to summarise the recent literature in the nanocellulose-based food packaging field and provide the readers with the state-of-the-art of this research area.

17.
Polymers (Basel) ; 14(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35566875

RESUMO

In this study, we reported PVA nanocomposite films enhanced by polyethyleneimine (PEI)-lignin contained cellulose nanofibers (LCNFs) via the solvent casting method. An easy and available method was preformed to prepare LCNFs using a supermasscolloider from unbleached bamboo waste after a mild alkaline pretreatment. The results demonstrate that LCNF-PEI can greatly improve mechanical, hydrophobic, anti-UV shielding and antibacterial properties of the composite films. The tensile strength of LPP1 film was improved to 54.56 MPa, which was higher than 39.37 MPa of PVA film. The water contact angle of films increased from 35° to 104° with an increase in LCNF content from 0 to 6 wt%. Meanwhile, the nanocomposite film demonstrated the effect of full shielding against ultraviolet light when the amount of LCNF-PEI reached 6 wt%. The addition of LCNF-PEI endowed excellent antibacterial activity (against S. aureus and E. coli), which indicated potential applications in the packaging field.

18.
Food Chem ; 379: 132142, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35063856

RESUMO

The mechanism of the high hydrostatic pressure (HHP) effect on horseradish peroxidase (HRP) is still unclear. The activity, thermal stability and structural changes of HRP after HHP treatments were studied in this work. Compared with the untreated sample, the enzyme activity reduces by 36% after 800 MPa processing. The results indicated that the conformation of the enzyme active center changes under pressure. Furthermore, HHP also changes the conformation of disulfide bonds and some secondary structures in HRP. These structural and conformational changes induce decreased activity. In addition, differential thermal scanning (DSC) results showed that the thermal denaturation temperature decreased from 103.74 °C to 85.78 °C after pressure treatment, suggesting HRP molecules formed large aggregates after pressure treatment. In this study, the interaction mechanism between pressure and enzyme was studied as well, and the results can provide some guidance for the application of HHP technology in fruit and vegetable products processing.


Assuntos
Pressão Hidrostática , Peroxidase do Rábano Silvestre , Estrutura Secundária de Proteína , Temperatura
19.
Polymers (Basel) ; 13(24)2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34960897

RESUMO

Bio-based composite films have been widely studied as potential substitutes for conventional plastics in food packaging. The aim of this study was to develop multifunctional composite films by introducing cellulose nanofibers (CNF) and lignin into starch-based films. Instead of costly and complicated chemical modification or covalent coupling, this study optimized the performance of the composite films by simply tuning the formulation. We found that starch films were mechanically reinforced by CNF, with lignin dispersing as nanoparticles embedded in the matrix. The newly built-up hydrogen bonding between these three components improves the integration of the films, while the introduction of CNF and lignin improved the thermal stability of the starch-based films. Lignin, as a functional additive, improved hydrophobicity and blocked UV transmission. The inherent barrier property of CNF and the dense starch matrix provided the composite films with good gas barrier properties. The prepared flexible films were optically transparent, and exhibited UV blocking ability, good oxygen-barrier properties, high hydrophobicity, appreciable mechanical strength and good thermal stability. These characteristics indicate potential utilization as a green alternative to synthetic plastics especially for food packaging applications.

20.
Exp Ther Med ; 22(5): 1342, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34630696

RESUMO

Long non-coding RNAs (lncRNAs) can function as onco-lncRNAs in several types of human cancer, including retinoblastoma (Rb). The present study investigated the potential role and regulatory mechanism of the lncRNA myocardial infarction-associated transcript (MIAT) in Rb. To do so, the expression levels of MIAT, microRNA (miR)-665, and LIM and SH3 protein 1 (LASP1) in Rb tissues from patients or Rb cells were analysed using reverse transcription quantitative PCR. The interactions between miR-665 and MIAT/LASP1 were confirmed by the dual-luciferase reporter assay. MTT, Transwell (to assess migration and invasion) and western blotting assays were used to explore the functions of the MIAT/miR-665/LASP1 axis on Rb progression in vitro. The results of the present study indicated that MIAT targeted miR-665. In Rb tissues and cell lines, high expression of MIAT was observed, whereas miR-665 was downregulated in Rb tissues. Furthermore, the proliferation and migratory and invasive abilities of Rb Y79 and HXO-RB44 cells were decreased following MIAT downregulation or miR-665 overexpression. In addition, LASP1 was identified as a target gene of miR-665. Both the decreased expression of miR-665 and the elevated expression of LASP1 reversed the suppressive effects of MIAT knockdown on the proliferation and migratory and invasive abilities of Y79 cells. Furthermore, MIAT silencing attenuated the development of Rb by regulating the miR-665/LASP1 axis. Taken together, these findings suggested that MIAT may be considered as a possible therapeutic target for Rb.

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