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1.
Eur J Immunol ; 54(6): e2350721, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38651231

RESUMO

Previous research suggests that group IIA-secreted phospholipase A2 (sPLA2-IIA) plays a role in and predicts lethal COVID-19 disease. The current study reanalyzed a longitudinal proteomic data set to determine the temporal relationship between levels of several members of a family of sPLA2 isoforms and the severity of COVID-19 in 214 ICU patients. The levels of six secreted PLA2 isoforms, sPLA2-IIA, sPLA2-V, sPLA2-X, sPLA2-IB, sPLA2-IIC, and sPLA2-XVI, increased over the first 7 ICU days in those who succumbed to the disease but attenuated over the same time period in survivors. In contrast, a reversed pattern in sPLA2-IID and sPLA2-XIIB levels over 7 days suggests a protective role of these two isoforms. Furthermore, decision tree models demonstrated that sPLA2-IIA outperformed top-ranked cytokines and chemokines as a predictor of patient outcome. Taken together, proteomic analysis revealed temporal sPLA2 patterns that reflect the critical roles of sPLA2 isoforms in severe COVID-19 disease.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/mortalidade , COVID-19/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Fosfolipases A2 Secretórias/sangue , Proteômica/métodos , Índice de Gravidade de Doença , Fosfolipases A2 do Grupo II/sangue , Adulto , Isoformas de Proteínas/sangue , Citocinas/sangue
2.
Small ; 20(12): e2307537, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939303

RESUMO

Constructing effective and robust biocatalysts with carbonic anhydrase (CA)-mimetic activities offers an alternative and promising pathway for diverse CO2-related catalytic applications. However, there is very limited success has been achieved in controllably synthesizing CA-mimetic biocatalysts. Here, inspired by the 3D coordination environments of CAs, this study reports on the design of an ultrafast ZnN3-OH2 center via tuning the 3D coordination structures and mesoporous defects in a zinc-dipyrazolate framework to serve as new, efficient, and robust CA-mimetic biocatalysts (CABs) to catalyze the hydration reactions. Owing to the structural advantages and high similarity with the active center of natural CAs, the double-walled CAB with mesoporous defects displays superior CA-like reaction kinetics in p-NPA hydrolysis (V0 = 445.16 nM s-1, Vmax = 3.83 µM s-1, turnover number: 5.97 × 10-3 s-1), which surpasses the by-far-reported metal-organic frameworks-based biocatalysts. This work offers essential guidance in tuning 3D coordination environments in artificial enzymes and proposes a new strategy to create high-performance CA-mimetic biocatalysts for broad applications, such as CO2 hydration/capture, CO2 sensing, and abundant hydrolytic reactions.

3.
Biomacromolecules ; 21(5): 1762-1775, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-31955566

RESUMO

Current therapy for liver failure and concomitant hyperbilirubinemia faces the challenge of poor hemocompatibility and bleeding risks associated with the anticoagulant injection. Herein, heparin-mimetic biomacromolecule (HepMBm) with a similar degree of sulfation and anticoagulant properties to heparin was synthesized by imitating the structure of natural biomacromolecule heparin. Then HepMBm was used to prepare nanocomposite spheres based on reduced graphene oxide (rGO). The formation of a dual-network structure in the spheres endowed the spheres with improved dimensional stability. The proposed spheres exhibited outstanding blood compatibilities and excellent self-anticoagulant properties. The bilirubin adsorption experiments and whole blood bilirubin removal assay indicated that the spheres exhibited high bilirubin removal capability from whole blood (The removal ratio was 99.69%.). The spheres open new routes for a therapeutic strategy without a plasma separation system and heparin pump, which may be a step toward a lightweight wearable artificial liver.


Assuntos
Fígado Artificial , Nanocompostos , Dispositivos Eletrônicos Vestíveis , Anticoagulantes/farmacologia , Bilirrubina
4.
Langmuir ; 35(5): 1430-1439, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30056716

RESUMO

Although abundant works have been developed in mussel-inspired antifouling coatings, most of them suffer from poor chemical stability, especially in a strongly alkaline environment. Herein, we report a robust one-step mussel-inspired method to construct a highly chemical stable and excellent antibiofouling membrane surface coating with a highly efficient codeposition of polydopamine (PDA) with zwitterionic polymer. In the study, PDA and polyethylenimine-quaternized derivative (PEI-S) are codeposited on the surface of poly(ether sulfone) (PES) ultrafiltration membrane in water at room temperature. In contrast to individual PDA coating, the obtained PDA/PEI-S coating exhibits excellent chemical stability even in a strongly alkaline environment owing to the cross-linking and unexpected cation-π interaction between the PEI-S and PDA. Thanks to the introduction of PEI-S, systematic protein adsorption tests and bacteria adhesion experiments demonstrated that the surfaces could prevent bovine serum fibrinogen and lysozyme adsorption and could reduce Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli adhesion. Benefiting from the versatile functionality of PDA, the proposed strategy is not limited to PES membrane surface but also others such as poly(ethylene terephthalate) sheets and commercial polypropylene microfiltration membranes. Overall, this work enriches the exploration of a remarkable coating with enhanced stability and excellent antifouling property via a facile, robust, and material-independent approach to modifying the membrane surface.

5.
Sensors (Basel) ; 17(12)2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29168772

RESUMO

We review some advances of the particle filtering (PF) algorithm that have been achieved in the last decade in the context of target tracking, with regard to either a single target or multiple targets in the presence of false or missing data. The first part of our review is on remarkable achievements that have been made for the single-target PF from several aspects including importance proposal, computing efficiency, particle degeneracy/impoverishment and constrained/multi-modal systems. The second part of our review is on analyzing the intractable challenges raised within the general multitarget (multi-sensor) tracking due to random target birth and termination, false alarm, misdetection, measurement-to-track (M2T) uncertainty and track uncertainty. The mainstream multitarget PF approaches consist of two main classes, one based on M2T association approaches and the other not such as the finite set statistics-based PF. In either case, significant challenges remain due to unknown tracking scenarios and integrated tracking management.

6.
Biomacromolecules ; 17(12): 4011-4020, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27936718

RESUMO

The aim of this study was to create heparin-like chitosan hydrogels (HLCHs) for blood purification. Herein, we prepared two heparin-like chitosans (HLCSs) with various carboxymethyl and sulfate groups, followed by a cross-linking reaction with glutaraldehyde. The synthetic chitosan derivatives were characterized by X-ray photoelectron spectroscopy, gel permeation chromatography, FTIR and NMR. The average sulfonation degrees of two HLCSs were 0.69 and 0.94 per sugar unit, respectively. The swelling ratio of the HLCH could reach up to 4800%, and the HLCHs remained a well-defined shape and stable below 170 °C. Moreover, the activated partial thromboplastin time and thrombin time results indicated that both of the HLCSs and their hydrogels exhibited excellent thrombus inhibition property. Furthermore, the contact activation and complement activation results also proved that the hydrogels possessed good blood compatibility and had the potential to be used as blood-contacting materials.


Assuntos
Materiais Biocompatíveis/química , Coagulação Sanguínea , Quitosana/química , Ativação do Complemento , Heparina/química , Hidrogéis/química , Humanos , Concentração Osmolar , Tempo de Coagulação do Sangue Total
7.
J Mater Sci Mater Med ; 27(2): 28, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26704545

RESUMO

In this study, polyethersulfone/poly (glycidyl methacrylate) particles are prepared via in situ cross-linked polymerization coupled with a phase inversion technique. The surfaces of these particles are then further modified by grafting amino groups using tetraethylenepentamine, dethylenetriamine, ethylenediamine, or 1,6-hexanediamine for the removal of bilirubin. The particles are characterized by Flourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Batch adsorption experiments are performed to verify the adsorption capability, and the effect of bilirubin initial concentration, bovine serum albumin concentration, and solution ionic strength on the adsorption is also investigated. In addition, both adsorption kinetic and isotherm models are applied to analyze the adsorption process of bilirubin, and a particle column is used to further study the bilirubin removal ability.To prove that the method was a universal portal to prepare functional particles, polysulfone, polystyrene, and poly(vinylidene fluoride) based functional particles were also prepared and used for the removal of bilirubin. This study and the results indicated that the particles had a great potential to be used in hemoperfusion treatment for hyperbilirubinemia.


Assuntos
Bilirrubina/isolamento & purificação , Hemoperfusão/instrumentação , Polímeros/química , Sulfonas/química , Adsorção , Animais , Bilirrubina/sangue , Bilirrubina/farmacocinética , Bovinos , Compostos de Epóxi/química , Compostos de Epóxi/farmacocinética , Hemoperfusão/métodos , Humanos , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/terapia , Teste de Materiais , Metacrilatos/química , Metacrilatos/farmacocinética , Microesferas , Polímeros/farmacocinética , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Sulfonas/farmacocinética , Temperatura
9.
Langmuir ; 30(45): 13622-30, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25347292

RESUMO

In this study, we provide a new method to modify poly(ether sulfone) (PES) membrane with good biocompatibility, for which diazotized PES (PES-N2(+)) membrane is covalently coated by a negatively charged copolymer of sodium sulfonated poly(styrene-alt-maleic anhydride) (NaSPS-MA). First, aminated PES (PES-NH2) is synthesized by nitro reduction reaction of nitro-PES (PES-NO2), and then blends with pristine PES to prepare PES/PES-NH2 membrane; then the membrane is treated with NaNO2 aqueous solution at acid condition; after surface diazo reaction, surface positively charged PES/PES-N2(+) membrane is prepared. Second, poly(styrene-alt-maleic anhydride) (PS-alt-MA) is synthesized, then sulfonated and treated by sodium hydroxide solution to obtain sodium sulfonated (PS-alt-MA) (NaSPS-MA). Finally, the negatively charged NaSPS-MA copolymer is coated onto the surface positively charged PES/PES-N2(+) membrane via electrostatic interaction; after UV-cross-linking, the linkage between the PES-N2(+) and NaSPS-MA changes to a covalent bond. The surface-modified PES membrane is characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS) analyses, and surface zeta potential analyses. The modified membrane exhibits good hemocompatibility and cytocompatibility, and the improved biocompatibility might have resulted from the existence of the hydrophilic groups (sodium carboxylate (-COONa) and sodium sulfonate (-SO3Na)). Moreover, the stability of the modified membrane is also investigated. The results indicated that the modified PES membrane using negatively charged copolymers had a lot of potential in blood purification fields and bioartificial liver supports for a long time.


Assuntos
Maleatos/química , Polímeros/química , Poliestirenos/química , Sulfonas/química , Adulto , Materiais Biocompatíveis/química , Células Cultivadas , Hepatócitos/citologia , Humanos , Masculino , Maleatos/síntese química , Estrutura Molecular , Adesividade Plaquetária , Poliestirenos/síntese química , Propriedades de Superfície
10.
Langmuir ; 30(18): 5115-25, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24754639

RESUMO

Development of blood compatible membranes is critical for biomedical applications. Zwitterionic polymers have been proved to be resistant to nonspecific protein adsorption and platelet adhesion. In this work, two kinds of zwitterionic copolymers bearing alkynyl and azide groups are synthesized by atom transfer radical polymerization (ATRP) and subsequent reactions, namely alkynyl-poly(sulfobetaine methacrylate) (alkynyl-PSBMA) and azide-poly(sulfobetaine methacrylate) (azide-PSBMA). The copolymers are directly used to modify azido-functionalized polysulfone (PSf-N3) membrane via click chemistry-enabled layer-by-layer (LBL) assembly. Alkynyl-citric acid is then clicked onto the membrane when the outermost layer was azide-PSBMA. The chemical compositions, surface morphologies, and hydrophilicity of the zwitterionic polymer and citric acid multilayer modified membranes are characterized. The composite multilayer is resistant to protein adsorption and platelet adhesion and also prolongs clotting times, indicating that the blood compatibility is improved. Moreover, after clicking the small molecule anticoagulant alkynyl-citric acid onto the outermost of the zwitterionic multilayer, the membrane shows further improved anticoagulant property. The deposition of zwitterionic polymer and citric acid via click chemistry-enabled LBL assembly can improve the blood compatibility of the PSf membrane.


Assuntos
Materiais Biocompatíveis/química , Ácido Cítrico/química , Química Click/métodos , Membranas Artificiais , Polímeros/química , Sulfonas/química , Materiais Biocompatíveis/efeitos adversos , Humanos
11.
Heliyon ; 10(7): e28381, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38633648

RESUMO

This paper proposes a new method for short-term electric load forecasting using a Ridgelet Neural Network (RNN) combined with a wavelet transform and optimized by a Self-Adapted (SA) Kho-Kho algorithm (SAKhoKho). The aim of this method is to improve the accuracy and reliability of electric load forecasting, which is essential for the planning and operation of competitive electrical networks. The proposed method uses the Wavelet Transform (WT) to decompose the load data into different frequency components and applies the RNN to each component separately. The RNN is, then, optimized by the SAKhoKho algorithm, which is an improved version of the KhoKho algorithm that can adapt the search parameters dynamically. The proposed method is trained and tested on the Zone Preliminary Billing Data from the PJM regulatory area, which is updated every two weeks based on the Intercontinental Exchange (ICE) figures. The proposed method is compared with six other cutting-edge methods from the literature, including SVM/SA, hybrid, ARIMA, MLP/PSO, CNN, and RNN/KhoKho/WT. The results show that the proposed method achieves the lowest Mean Absolute Error (MAE) of 7.7704 and Root Mean Square Error (RMSE) of 17.4132 among all the methods, indicating its superior performance. The proposed method can capture the temporal dependencies in the load data and optimize the RNN's weights to minimize the error function. The proposed method is a promising technique for electric load forecasting, as it can provide accurate and reliable predictions for the next hour based on the previous 24 h of data.

12.
J Mater Chem B ; 12(15): 3594-3613, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38506127

RESUMO

Blood purification, such as hemodialysis (HD), plasma exchange (PE), and hemoperfusion (HP), is widely applied in patients with organ failure (such as kidney and liver failure). Among them, HP mainly relies on porous adsorbents to efficiently adsorb accumulated metabolic wastes and toxins, thus improving purification efficiency. Metal-organic frameworks (MOFs), with a high porosity, large surface area, high loading capacity, and tailorable topology, are emerging as some of the most promising materials for HP. Compared with non-metal framework counterparts, the self-built metal centers of MOFs feature the intrinsic advantages of coordination with toxin molecules. However, research on MOFs in blood purification is insufficient, particularly in contrast to materials applied in other biomedical applications. Thus, to broaden this area, this review first discusses the essential characteristics, potential mechanisms, and structure-function relationship between MOFs and toxin adsorption based on porosity, topology, ligand functionalization, metal centers, and toxin types. Moreover, the stability, utilization safety, and hemocompatibility of MOFs are illustrated for adsorbent selection. The current development and progress in MOF composites for HD, HP, and extracorporeal membrane oxygenation (ECMO) are also summarized to highlight their practicability. Finally, we propose future opportunities and challenges from materials design and manufacture to the computational prediction of MOFs in blood purification. It is anticipated that our review will expand the interest of researchers for more impact in this area.


Assuntos
Hemoperfusão , Estruturas Metalorgânicas , Humanos , Adsorção , Rim , Porosidade
13.
J Mater Chem B ; 12(9): 2364-2372, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38345129

RESUMO

The introduction of carbonic anhydrase (CA) onto an extracorporeal membrane oxygenation (ECMO) membrane can improve the permeability of carbon dioxide (CO2). However, existing CA-grafting methods have limitations, and the hemocompatibility of current substrate membranes of commercial ECMO is not satisfactory. In this study, a 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC)/N-hydroxy succinimide (NHS) activation method is adopted to graft CA with CO2-catalyzed conversion activity onto a polyethersulfone (PES) membrane, which is prepared by a phase inversion technique after in situ crosslinking polymerization of 1-vinyl-2-pyrrolidone (VP) and acrylic acid (AA) in PES solution. The characterization results reveal that CA has been grafted onto the modified PES membrane successfully and exhibits catalytic activity. The kinetic parameters of esterase activity verify that the grafted amount of active CA increases with an increase in the concentration of the CA incubation solution. The CA-grafted membrane (CA-M) can accelerate the conversion of bicarbonate to CO2 in water and blood, which demonstrates the special catalytic activity towards bicarbonate of CA. Finally, blood compatibility tests prove that the CA-M does not lead to hemolysis, shows suppressed protein adsorption and increased coagulation time, and is suitable for application in ECMO. This work demonstrates a green and efficient method for preparing bioactive materials and has practical guiding significance for subsequent pulmonary membrane research and ECMO applications.


Assuntos
Anidrases Carbônicas , Polímeros , Sulfonas , Anidrases Carbônicas/metabolismo , Dióxido de Carbono , Bicarbonatos , Membranas Artificiais , Pulmão/metabolismo
14.
Bioinform Biol Insights ; 18: 11779322241261427, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39081667

RESUMO

The secreted phospholipase A2 (sPLA2) isoform, sPLA2-IIA, has been implicated in a variety of diseases and conditions, including bacteremia, cardiovascular disease, COVID-19, sepsis, adult respiratory distress syndrome, and certain cancers. Given its significant role in these conditions, understanding the regulatory mechanisms impacting its levels is crucial. Genome-wide association studies (GWAS) have identified several single nucleotide polymorphisms (SNPs), including rs11573156, that are associated with circulating levels of sPLA2-IIA. The work in the manuscript leveraged 4 publicly available datasets to investigate the mechanism by which rs11573156 influences sPLA2-IIA levels via bioinformatics and modeling analysis. Through genotype-tissue expression (GTEx), 234 expression quantitative trait loci (eQTLs) were identified for the gene that encodes for sPLA2-IIA, PLA2G2A. SNP2TFBS was used to ascertain the binding affinities between transcription factors (TFs) to both the reference and alternative alleles of identified eQTL SNPs. Subsequently, candidate TF-SNP interactions were cross-referenced with the ChIP-seq results in matched tissues from ENCODE. SP1-rs11573156 emerged as the significant TF-SNP pair in the liver. Further analysis revealed that the upregulation of PLA2G2A transcript levels through the rs11573156 variant was likely affected by tissue SP1 protein levels. Using an ordinary differential equation based on Michaelis-Menten kinetic assumptions, we modeled the dependence of PLA2G2A transcription on SP1 protein levels, incorporating the SNP influence. Collectively, our analysis strongly suggests that the difference in the binding dynamics of SP1 to different rs11573156 alleles may underlie the allele-specific PLA2G2A expression in different tissues, a mechanistic model that awaits future direct experimental validation. This mechanism likely contributes to the variation in circulating sPLA2-IIA protein levels in the human population, with implications for a wide range of human diseases.

15.
Nutrients ; 16(17)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39275249

RESUMO

Conflicting clinical trial results on omega-3 highly unsaturated fatty acids (n-3 HUFA) have prompted uncertainty about their cardioprotective effects. While the VITAL trial found no overall cardiovascular benefit from n-3 HUFA supplementation, its substantial African American (AfAm) enrollment provided a unique opportunity to explore racial differences in response to n-3 HUFA supplementation. The current observational study aimed to simulate randomized clinical trial (RCT) conditions by matching 3766 AfAm and 15,553 non-Hispanic White (NHW) individuals from the VITAL trial utilizing propensity score matching to address the limitations related to differences in confounding variables between the two groups. Within matched groups (3766 AfAm and 3766 NHW), n-3 HUFA supplementation's impact on myocardial infarction (MI), stroke, and cardiovascular disease (CVD) mortality was assessed. A weighted decision tree analysis revealed belonging to the n-3 supplementation group as the most significant predictor of MI among AfAm but not NHW. Further logistic regression using the LASSO method and bootstrap estimation of standard errors indicated n-3 supplementation significantly lowered MI risk in AfAm (OR 0.17, 95% CI [0.048, 0.60]), with no such effect in NHW. This study underscores the critical need for future RCT to explore racial disparities in MI risk associated with n-3 HUFA supplementation and highlights potential causal differences between supplementation health outcomes in AfAm versus NHW populations.


Assuntos
Negro ou Afro-Americano , Suplementos Nutricionais , Ácidos Graxos Ômega-3 , Aprendizado de Máquina , Infarto do Miocárdio , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Graxos Ômega-3/administração & dosagem , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/etnologia , Pontuação de Propensão , Fatores de Risco , Brancos
16.
Langmuir ; 29(26): 8311-9, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23745767

RESUMO

A photoresponsive molecularly imprinted system was prepared on a silicon wafer substrate surface via the host-guest complex of grafted 4-(3-triethoxysilylpropyiureido)azobenzene (TSUA) and mono-6-deoxy-6-((p-chlorosulfonyl)-benzoic acid)-ß-cyclodextrin (CBA-ß-CD), and the acid-base pair interactions/hydrogen bonds between CBA-ß-CD and the template molecules, including theophylline (TPE) and 4-hydroxybenzoic acid (4-HA). A molecular imprinting cycle "imprinting → extracting → uptaking → shuffling" was also defined in the study, the processes of uptaking and shuffling were investigated in detail by equilibrium binding experiments, and the Langmuir adsorption isotherm and Scatchard equation were used to evaluate the binding affinity and the theoretical binding sites of the molecularly imprinted (MIS), nonimprinted (NIS), and pure (PS) silicon wafer substrates. Compared with the NISs and PSs, the MISs showed a significantly higher adsorption capacity for the template molecules. More importantly, the MISs showed a reimprinted ability; after the process of shuffling, the molecularly imprinted systems on the substrate surface were destroyed, and new imprinted systems could be fabricated for the recognition of other template molecules after washing the substrates under irradiation at 450 nm. Moreover, the selective adsorption for the MISs was investigated, which indicated that the MISs showed specific affinity to the template molecules (TPE or 4-HA).

17.
bioRxiv ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38168258

RESUMO

The secreted phospholipase A 2 (sPLA 2 ) isoform, sPLA 2 -IIA, has been implicated in a variety of diseases and conditions, including bacteremia, cardiovascular disease, COVID-19, sepsis, adult respiratory distress syndrome, and certain cancers. Given its significant role in these conditions, understanding the regulatory mechanisms impacting its levels is crucial. Genome-wide association studies (GWAS) have identified several single nucleotide polymorphisms (SNPs), including rs11573156, that are associated with circulating levels of sPLA 2 -IIA. Through Genotype-Tissue Expression (GTEx), 234 expression quantitative trait loci (eQTLs) were identified for the gene that encodes for sPLA 2 -IIA, PLA2G2A . SNP2TFBS ( https://ccg.epfl.ch/snp2tfbs/ ) was utilized to ascertain the binding affinities between transcription factors (TFs) to both the reference and alternative alleles of identified SNPs. Subsequently, ChIP-seq peaks highlighted the TF combinations that specifically bind to the SNP, rs11573156. SP1 emerged as a significant TF/SNP pair in liver cells, with rs11573156/SP1 interaction being most prominent in liver, prostate, ovary, and adipose tissues. Further analysis revealed that the upregulation of PLA2G2A transcript levels through the rs11573156 variant was affected by tissue SP1 protein levels. By leveraging an ordinary differential equation, structured upon Michaelis-Menten enzyme kinetics assumptions, we modeled the PLA2G2A transcription's dependence on SP1 protein levels, incorporating the SNP's influence. Collectively, these data strongly suggest that the binding affinity differences of SP1 for the different rs11573156 alleles can influence PLA2G2A expression. This, in turn, can modulate sPLA2-IIA levels, impacting a wide range of human diseases.

18.
Langmuir ; 28(37): 13284-93, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22894645

RESUMO

In the present study, photoresponsive surface molecularly imprinted poly(ether sulfone) microfibers are prepared via nitration reaction, the wet-spinning technique, surface nitro reduction reaction, and surface diazotation reaction for the selectively photoregulated uptake and release of 4-hydrobenzoic acid. The prepared molecularly imprinted microfibers show selective binding to 4-HA under irradiation at 450 nm and release under irradiation at 365 nm. The simple, convenient, effective, and productive method for the preparation of azo-containing photoresponsive material is also applied to the modification of polysulfone and poly(ether ether ketone). All three benzene-ring-containing polymers show significant photoresponsibility after the azo modification.


Assuntos
Impressão Molecular , Polímeros/síntese química , Sulfonas/síntese química , Estrutura Molecular , Processos Fotoquímicos , Polímeros/química , Sulfonas/química , Propriedades de Superfície
19.
Biomacromolecules ; 13(12): 4236-46, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-23152977

RESUMO

Graphene oxide (GO), reduced graphene oxide (rGO), and their derivatives are investigated for various biomedical applications explosively. However, the defective biocompatibility was also recognized, which restricted their potential applications as biomaterials. In this study, a facile biomimetic approach for preparation of biopolymer adhered GO (rGO) with controllable 2D morphology and excellent biocompatibility was proposed. Mussel-inspired adhesive molecule dopamine (DA) was grafted onto heparin backbone to obtain DA grafted heparin (DA-g-Hep) by carbodiimide chemistry method; then, DA-g-Hep was used to prepare heparin-adhered GO (Hep-a-GO) and heparin-adhered rGO (Hep-a-rGO). The obtained heparin-adhered GO (rGO) showed controllable 2D morphology, ultrastable property in aqueous solution, and high drug and dye loading capacity. Furthermore, the biocompatibility of the heparin-adhered GO (rGO) was investigated using human blood cells and human umbilical vein endothelial cells, which indicated that the as-prepared heparin-adhered GO (rGO) exhibited ultralow hemolysis ratio (lower than 1.2%) and high cell viability. Moreover, the highly anticoagulant bioactivity indicated that the adhered heparin could maintain its biological activity after immobilization onto the surface of GO (rGO). The excellent biocompatibility and high bioactivity of the heparin-adhered GO (rGO) might confer its great potentials for various biomedical applications.


Assuntos
Adesivos/química , Biomimética/métodos , Biopolímeros/química , Dopamina/química , Grafite/química , Óxidos/química , Materiais Biocompatíveis/química , Sobrevivência Celular , Hemólise , Heparina/química , Células Endoteliais da Veia Umbilical Humana , Humanos
20.
Biomater Adv ; 142: 213154, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36341743

RESUMO

Chronic infected wound healing is a critical challenge in clinical practice owing to the involvement of multiple physiological processes, including bacteria-related, inflammatory regulation and angiogenesis. Therefore, a multi-functional strategy with synergistic anti-bacterial, anti-inflammatory and pro-angiogenic effects should be developed. Owing to their biomimetic structural features and controlled delivery of active agents, electrospun nanofilms are promising biomaterials for the treatment of skin defects. In this study, we fabricated multi-functional nanofilms with pro-angiogenic, anti-bacterial and anti-inflammatory capacities. First, strontium (Sr) ions were incorporated into poly(L-lactic-co-caprolactone) (PLCL) nanofilms. Subsequently, polydopamine (PDA) and zinc oxide (ZnO) were decorated onto the surface of Sr-loaded PLCL nanofilms to prepare ZnO/PDA@PLCL@Sr nanofilms. In vitro results showed that ZnO/PDA@PLCL@Sr nanofilms were biocompatible, exhibited angiogenic activity and significantly inhibited the growth of Staphylococcus aureus and Escherichia coli upon near-infrared -light irradiation. Furthermore, ZnO/PDA@PLCL@Sr nanofilms were found to drive the transformation of macrophages into the M2 phenotype. In vivo results further validated that ZnO/PDA@PLCL@Sr nanofilms exhibited pro-angiogenic and anti-bacterial activities and regulated inflammation to accelerate wound -healing in a rat model of bacteria-infected skin defects. In conclusion, we successfully developed a multi-functional biomaterial with pro-angiogenic, anti-bacterial and anti-inflammatory capacities to treat chronic infected wounds.


Assuntos
Óxido de Zinco , Ratos , Animais , Óxido de Zinco/farmacologia , Cicatrização , Staphylococcus aureus , Escherichia coli , Materiais Biocompatíveis/farmacologia , Estrôncio/farmacologia
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