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1.
Environ Res ; 247: 118258, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262512

RESUMO

Developing efficient catalytic systems for water contamination removal is a topic of great interest. However, the use of heterogeneous catalysts faces challenges due to insufficient active sites and electron cycling. In this study, results from first-principles calculations demonstrate that dual reaction centers (DRCs) are produced around the Cu and Mn sites in Cu1.0/Mn1.0-ZnO due to the electronegativity difference. Experimental results reveal the material with DRCs greatly enhances electron transfer efficiency and significantly impacts the oxidation and reduction of peroxymonosulfate (PMS). In addition, the self-consistent potential correction (SCPC) method was introduced to correct the energy and charge of charged periodic systems simulating a catalytic process, resulting in more precise catalytic results. Specifically, the material exhibits a preference for adsorbing negatively charged PMS anions at electron-deficient Mn sites, facilitating PMS oxidation for the generation of 1O2, and PMS reduction around the electron-rich Cu for the formation of •OH and SO4•-. The major reactive oxygen species is 1O2, showcasing effective performance in various degradation systems. Overall, our work provides novel insights into the persulfate-based heterogeneous catalytic oxidation process, paving the way for the development of high-performance catalytic systems for water purification.


Assuntos
Óxido de Zinco , Peróxidos , Espécies Reativas de Oxigênio , Catálise
2.
Int Wound J ; 21(5): e14888, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38686514

RESUMO

Allografts derived from live-birth tissue obtained with donor consent have emerged as an important treatment option for wound and soft tissue repairs. Placental membrane derived from the amniotic sac consists of the amnion and chorion, the latter of which contains the trophoblast layer. For ease of cleaning and processing, these layers are often separated with or without re-lamination and the trophoblast layer is typically discarded, both of which can negatively affect the abundance of native biological factors and make the grafts difficult to handle. Thus, a full-thickness placental membrane that includes a fully-intact decellularized trophoblast layer was developed for homologous clinical use as a protective barrier and scaffold in soft tissue repairs. Here, we demonstrate that this full-thickness placental membrane is effectively decellularized while retaining native extracellular matrix (ECM) scaffold and biological factors, including the full trophoblast layer. Following processing, it is porous, biocompatible, supports cell proliferation in vitro, and retains its biomechanical strength and the ability to pass through a cannula without visible evidence of movement or damage. Finally, it was accepted as a natural scaffold in vivo with evidence of host-cell infiltration, angiogenesis, tissue remodelling, and structural layer retention for up to 10 weeks in a murine subcutaneous implant model.


Assuntos
Placenta , Humanos , Feminino , Gravidez , Animais , Camundongos , Alicerces Teciduais , Liofilização/métodos , Matriz Extracelular Descelularizada , Cicatrização/fisiologia
3.
Apoptosis ; 28(1-2): 124-135, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36241947

RESUMO

The Notch signaling pathway is related to endothelial dysfunction in coronary atherosclerosis. Our objective was to explore the role of Notch signaling in coronary microvascular dysfunction (CMD). CMD models were constructed by sodium laurate injection in vivo and homocysteine (Hcy) stimulation in vitro. The binding ability of Notch Intracellular Domain (NICD)/H3K9Ac/GCN5 (General Control Non-derepressible 5) to Neuregulin-1 (Nrg-1) promoter was examined by chromatin immunoprecipitation. Immunofluorescence staining was conducted to detect CD31 positive cells, NICD localization, and co-localization of NICD and GCN5. Flow cytometry and Tunel staining were conducted to identify the apoptosis. Hematoxylin and eosin staining, quantitative real-time PCR, western blot, immunohistochemical staining, co-immunoprecipitation, and double luciferase report analysis were also conducted. Notch signaling pathway-related protein levels were decreased, levels of Nrg-1 and the phosphorylation of ErbB2 and ErbB4 were enhanced in CMD models. Interference with Nrg-1 further increased the apoptosis in Hcy-induced cardiac microvascular endothelial cells (CMECs). Meanwhile, the activation of the Notch signaling pathway increased the levels of Nrg-1 and the phosphorylation of ErbB2 and ErbB4, as well as inhibited the apoptosis induced by Hcy. Furthermore, NICD and histone acetyltransferase enzyme GCN5 could regulate Nrg-1 promoter activity by affecting the expression of acetylation-modified protein H3K9Ac. In addition, NICD also interacted with GCN5. In vivo results also confirmed that the activation of the Notch signal alleviated CMD. Notch signaling pathway regulates Nrg-1 level through synergistic interaction with GCN5, thereby mitigating CMD.


Assuntos
Células Endoteliais , Isquemia Miocárdica , Humanos , Células Endoteliais/metabolismo , Neuregulina-1/metabolismo , Neuregulina-1/farmacologia , Código das Histonas , Apoptose , Transdução de Sinais , Receptor ErbB-4/metabolismo , Isquemia Miocárdica/metabolismo , Receptor Notch1
4.
BMC Bioinformatics ; 23(1): 521, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471248

RESUMO

BACKGROUND: Protein-protein interactions are widespread in biological systems and play an important role in cell biology. Since traditional laboratory-based methods have some drawbacks, such as time-consuming, money-consuming, etc., a large number of methods based on deep learning have emerged. However, these methods do not take into account the long-distance dependency information between each two amino acids in sequence. In addition, most existing models based on graph neural networks only aggregate the first-order neighbors in protein-protein interaction (PPI) network. Although multi-order neighbor information can be aggregated by increasing the number of layers of neural network, it is easy to cause over-fitting. So, it is necessary to design a network that can capture long distance dependency information between amino acids in the sequence and can directly capture multi-order neighbor information in protein-protein interaction network. RESULTS: In this study, we propose a multi-hop neural network (LDMGNN) model combining long distance dependency information to predict the multi-label protein-protein interactions. In the LDMGNN model, we design the protein amino acid sequence encoding (PAASE) module with the multi-head self-attention Transformer block to extract the features of amino acid sequences by calculating the interdependence between every two amino acids. And expand the receptive field in space by constructing a two-hop protein-protein interaction (THPPI) network. We combine PPI network and THPPI network with amino acid sequence features respectively, then input them into two identical GIN blocks at the same time to obtain two embeddings. Next, the two embeddings are fused and input to the classifier for predict multi-label protein-protein interactions. Compared with other state-of-the-art methods, LDMGNN shows the best performance on both the SHS27K and SHS148k datasets. Ablation experiments show that the PAASE module and the construction of THPPI network are feasible and effective. CONCLUSIONS: In general terms, our proposed LDMGNN model has achieved satisfactory results in the prediction of multi-label protein-protein interactions.


Assuntos
Redes Neurais de Computação , Proteínas , Sequência de Aminoácidos , Proteínas/metabolismo , Mapas de Interação de Proteínas , Aminoácidos/metabolismo
5.
BMC Bioinformatics ; 23(1): 224, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689200

RESUMO

BACKGROUND: Drug-Drug interactions (DDIs) are a challenging problem in drug research. Drug combination therapy is an effective solution to treat diseases, but it can also cause serious side effects. Therefore, DDIs prediction is critical in pharmacology. Recently, researchers have been using deep learning techniques to predict DDIs. However, these methods only consider single information of the drug and have shortcomings in robustness and scalability. RESULTS: In this paper, we propose a multi-type feature fusion based on graph neural network model (MFFGNN) for DDI prediction, which can effectively fuse the topological information in molecular graphs, the interaction information between drugs and the local chemical context in SMILES sequences. In MFFGNN, to fully learn the topological information of drugs, we propose a novel feature extraction module to capture the global features for the molecular graph and the local features for each atom of the molecular graph. In addition, in the multi-type feature fusion module, we use the gating mechanism in each graph convolution layer to solve the over-smoothing problem during information delivery. We perform extensive experiments on multiple real datasets. The results show that MFFGNN outperforms some state-of-the-art models for DDI prediction. Moreover, the cross-dataset experiment results further show that MFFGNN has good generalization performance. CONCLUSIONS: Our proposed model can efficiently integrate the information from SMILES sequences, molecular graphs and drug-drug interaction networks. We find that a multi-type feature fusion model can accurately predict DDIs. It may contribute to discovering novel DDIs.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Redes Neurais de Computação , Interações Medicamentosas , Fusão Gênica , Humanos
6.
J Environ Sci (China) ; 122: 115-127, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35717077

RESUMO

The coronavirus (COVID-19) pandemic is disrupting the world from many aspects. In this study, the impact of emission variations on PM2.5-bound elemental species and health risks associated to inhalation exposure has been analyzed based on real-time measurements at a remote coastal site in Shanghai during the pandemic. Most trace elemental species decreased significantly and displayed almost no diel peaks during the lockdown. After the lockdown, they rebounded rapidly, of which V and Ni even exceeded the levels before the lockdown, suggesting the recovery of both inland and shipping activities. Five sources were identified based on receptor modeling. Coal combustion accounted for more than 70% of the measured elemental concentrations before and during the lockdown. Shipping emissions, fugitive/mineral dust, and waste incineration all showed elevated contributions after the lockdown. The total non-carcinogenic risk (HQ) for the target elements exceeded the risk threshold for both children and adults with chloride as the predominant species contributing to HQ. Whereas, the total carcinogenic risk (TR) for adults was above the acceptable level and much higher than that for children. Waste incineration was the largest contributor to HQ, while manufacture processing and coal combustion were the main sources of TR. Lockdown control measures were beneficial for lowering the carcinogenic risk while unexpectedly increased the non-carcinogenic risk. From the perspective of health effects, priorities of control measures should be given to waste incineration, manufacture processing, and coal combustion. A balanced way should be reached between both lowering the levels of air pollutants and their health risks.


Assuntos
Poluentes Atmosféricos , COVID-19 , Adulto , Poluentes Atmosféricos/análise , COVID-19/epidemiologia , Carcinógenos , Criança , China/epidemiologia , Carvão Mineral/análise , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Pandemias , Material Particulado/análise , Medição de Risco , Estações do Ano
7.
Biochem Biophys Res Commun ; 557: 8-13, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33857842

RESUMO

Precise quantification of vascular developments in Zebrafish requires continuous in-vivo 3D imaging. Here we employed a bi-directional light-sheet illumination microscope to characterize the development process of Zebrafish's intersegmental vessels. A Virtual Reality-based method was used to measure the lengths of intersegmental vessels (ISVs). The quantified growth rates of typical ISVs can be plotted, and unusual growth of some specific vessels was also observed.


Assuntos
Vasos Sanguíneos/embriologia , Embrião não Mamífero/irrigação sanguínea , Microscopia/instrumentação , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Vasos Sanguíneos/crescimento & desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imageamento Tridimensional/métodos , Iluminação , Microscopia/métodos , Neovascularização Fisiológica , Peixe-Zebra/crescimento & desenvolvimento
8.
J Interv Cardiol ; 2021: 2632343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34934407

RESUMO

BACKGROUND: The revascularization of small vessels using drug-eluting stents remains challenging. The use of the drug-coated balloon is an attractive therapeutic strategy in de novo lesions in small coronary vessels, particularly in the diabetic group. This study aimed to assess the outcomes of DCB-only angioplasty in small vessel disease. METHODS: A total of 1198 patients with small vessel disease treated with DCB-only strategy were followed. Patients were divided into the diabetic and nondiabetic groups. Clinical and angiographical follow-up were organized at 12 months. The primary endpoints were target lesion failure and secondary major adverse cardiac events. RESULTS: There was a significantly higher rate of target lesion failure among diabetic patients compared to nondiabetic [17 (3.9%) vs. 11 (1.4%), P=0.006], taken separately, the rate of target lesion revascularization significantly differed between groups with a higher rate observed in the diabetic group [9 (2%) vs. 4 (0.5%), P=0.014]. Diabetes mellitus remained an independent predictor for TLF (HR: 2.712, CI: 1.254-5.864, P=0.011) and target lesion revascularization (HR: 3.698, CI: 1.112-12.298, P=0.033) after adjustment. However, no significant differences were observed between groups regarding the target vessel myocardial infarction (0.6% vs. 0.1%, P=0.110) and MACE [19 (4.4%) vs. 21 (2.7%), P=0.120]. CONCLUSION: Drug-coated balloon-only treatment achieved lower incidence rates of TLF and MACE. Diabetes is an independent predictor for target lesion failure and target lesion revascularization at one year following DCB treatment in small coronary vessels. We observed no significant differences between groups regarding MACE in one year.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana , Diabetes Mellitus , Preparações Farmacêuticas , Angiografia Coronária , Doença da Artéria Coronariana/cirurgia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Diabetes Mellitus/epidemiologia , Humanos , Resultado do Tratamento
9.
J Shoulder Elbow Surg ; 30(9): 2146-2155, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33600900

RESUMO

BACKGROUND: Acellular dermal matrix (ADM) allografts are commonly used in the surgical treatment of complex and irreparable rotator cuff tears. Multiple studies report that superior capsule reconstruction (SCR) using ADM has resulted in short-term clinical success as assessed via radiographic and patient-reported outcomes. However, limited information is available regarding the biologic fate of these grafts in human subjects. This case series describes histologic results from 8 patients who had reoperations, during which the previously implanted ADMs were removed. These explanted ADMs were subjected to histologic analysis with the hypothesis that they would have evidence of recellularization, revascularization, and active remodeling. METHODS: Eight patients, 38-82 years old, underwent reoperation 6-38 months after undergoing SCR. ADM explants were voluntarily shipped to the manufacturer for histologic analysis. Each graft's structure and composition were qualitatively evaluated by 1 or more of the following histologic stains: hematoxylin and eosin, safranin O, and Russell-Movat pentachrome. Pan-muscle actin staining also assessed the level of neovascularization, potential myoblast or myocyte infiltration, and muscle tissue development in the graft, and was analyzed to determine the proportion of graft that had been recellularized in situ. RESULTS: Grafts showed varying levels of gross and microscopic incorporation with the host. An uneven, but high, overall degree of recellularization, revascularization, and active remodeling was observed. The degree of remodeling correlated with implant duration. These results are consistent with successful biologic reconstruction of the superior shoulder capsule. CONCLUSIONS: The present histologic analysis suggests that ADMs used in SCR undergo active recellularization, revascularization, and remodeling as early as 6 months after implantation, and that graft recellularization positively correlates with duration of implantation. These results represent a significant advancement in our knowledge regarding biologic incorporation of ADMs used in SCR.


Assuntos
Derme Acelular , Lesões do Manguito Rotador , Articulação do Ombro , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Manguito Rotador , Transplante Homólogo
10.
Angew Chem Int Ed Engl ; 60(5): 2232-2256, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32128948

RESUMO

Mitochondria are the powerhouse of cells. They are vital organelles that maintain cellular function and metabolism. Dysfunction of mitochondria results in various diseases with a great diversity of clinical appearances. In the past, strategies have been developed for fabricating subcellular-targeting drug-delivery nanocarriers, enabling cellular internalization and subsequent organelle localization. Of late, innovative strategies have emerged for the smart design of multifunctional nanocarriers. Hierarchical targeting enables nanocarriers to evade and overcome various barriers encountered upon in vivo administration to reach the organelle with good bioavailability. Stimuli-responsive nanocarriers allow controlled release of therapeutics to occur at the desired target site. Synergistic therapy can be achieved using a combination of approaches such as chemotherapy, gene and phototherapy. In this Review, we survey the field for recent developments and strategies used in the smart design of nanocarriers for mitochondria-targeted therapeutics. Existing challenges and unexplored therapeutic opportunities are also highlighted and discussed to inspire the next generation of mitochondrial-targeting nanotherapeutics.


Assuntos
Mitocôndrias/metabolismo , Nanopartículas/normas , Nanoestruturas/normas , Humanos
11.
World J Urol ; 38(9): 2133-2138, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201521

RESUMO

PURPOSE: Several graft materials are available for use in the treatment of urethral stricture disease. Placental membrane is being used in a variety of settings as a graft in wound healing and tissue repair. We aim to evaluate the effect of implanting decellularized human placental membrane into rabbit urethras. METHODS: Dorsal onlay graft urethroplasty using prepared human placental membrane was performed in 10 New Zealand White rabbits (Oryctolagus cuniculus). After 3 months, the rabbits underwent cystourethroscopy to evaluate urethral patency. The rabbits were then euthanized and the urethras examined for pathological findings. RESULTS: All urethroplasties were performed without complication. There were no observed episodes of urinary retention, infection, or renal failure. Urethral patency was achieved in all rabbits 3 months postoperatively. Urothelial replacement of the placental membrane graft was observed in all rabbits without malignant transformation. CONCLUSION: Dorsal onlay urethroplasty using decellularized human placental membrane can safely be performed in a rabbit model. This pilot study demonstrated urothelial replacement of human placental membrane in the rabbit urethra without stricture formation. Placental membrane is a promising biomaterial for urethral reconstruction.


Assuntos
Placenta/transplante , Uretra/cirurgia , Estreitamento Uretral/cirurgia , Animais , Técnicas Citológicas , Modelos Animais de Doenças , Feminino , Membranas/citologia , Membranas/transplante , Projetos Piloto , Placenta/citologia , Gravidez , Coelhos , Procedimentos Cirúrgicos Urológicos Masculinos/métodos
12.
Bioorg Chem ; 98: 103698, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32217369

RESUMO

Quorum sensing (QS) is a density-dependent form of cell-cell communication that triggers the functional coordination of cooperative behaviors such as the production of virulence factors and biofilm formation. Quorum quenching (QQ) refers to all processes involved in the disruption of QS and is regarded as a promising strategy for treating bacterial infections. Herein, four compounds with closely related chemical structures to homoserine γ-lactone were synthesized and fully characterized. The compounds are termed TGK-series compounds. These compounds were subsequently tested in their QS inhibition activity using an E. coli Top 10 QS biosensor strain, a GFP QS reporter, that probes the capacity of bacteria to detect their cognate autoinducer N-(3-oxohexanoyl)-homoserine lactone (3OC6HSL) substrate by means of a single intracellular protein LuxR. All TGK-series compounds were found to significantly inhibit the ability of bacteria to produce GFP but without exerting toxicity when applied at a concentration of 50 µM. In parallel, the interaction of TGK-series compounds with LuxR were studied by molecular docking simulations. These studies revealed that TGK-series compounds bound to the natural substrate N-(3-oxo-octanoyl)-l-homoserine lactone (OOHL) binding site and that the binding ability of the compounds with the TraR protein (a surrogate of LuxR) was even more favorable in comparison with the natural substrate. It was also uncovered that TGK-series compounds form stronger hydrophobic interactions with the TraR protein than 3OC6HSL does, thus providing a rationale for the enhancement of the QQ activity of the synthetic TGK-series compounds. This study will serve to guide future works aimed to design promising novel QS inhibitor candidates on a rational basis.


Assuntos
4-Butirolactona/análogos & derivados , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , 4-Butirolactona/síntese química , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
13.
Anal Bioanal Chem ; 411(23): 6165-6172, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31312882

RESUMO

The copper(II) ion (Cu2+) has played an indispensable role in diverse kinds of functional physiological processes of organisms, which has become of growing interest. Despite the fact that numerous Cu2+ test papers using fluorescent probes have been fabricated, sensors featuring the ratiometric property that integrates quenched probes and an inner standard dye are rarely reported. Herein, a two-component ratiometric sensor in a paper-based device is proposed to realize highly selective Cu2+ detection. To overcome shortcomings such as low signal-to-noise ratio and incorrect response of the quenching probe, a novel BODIPY-based turn-off probe (P2017) is designed and introduced into the paper-based device with better water solubility and selectivity for Cu2+ detection. Furthermore, a reference dye (B001), exhibiting an emission at 690 nm when the excitation wavelength is 480 nm, is also introduced into the paper-based device. These two components can enhance the quality of the signal as P2017 is sensitively quenched by Cu2+, while B001 with a photostable property, serving as an internal benchmark, is unable to react with Cu2+. The results indicated that the two components provided a new concept for optimizing paper-based device fabrication and developing accurate, simple, and inexpensive Cu2+ detection methods, which could be potentially applied to monitor human health and the environment in remote areas. Graphical abstract.


Assuntos
Técnicas Biossensoriais/instrumentação , Compostos de Boro/química , Cobre/análise , Corantes Fluorescentes/química , Papel , Cátions Bivalentes/análise , Desenho de Equipamento , Células Hep G2 , Humanos
14.
Arthroscopy ; 35(10): 2950-2958, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31604517

RESUMO

Acellular human dermal allograft commonly is used in the surgical treatment of complex rotator cuff tears, but little information is known about the biological fate of these grafts in human subjects. In this case report, the authors describe a patient who presented with a radiographically healed acellular human dermal allograft superior capsular reconstruction but had humeral head avascular necrosis. The healed superior capsular reconstruction, including graft-bone interfaces, was explanted after 7 months and sent for histologic analysis. A successful biological reconstruction of the superior capsule was found. The graft demonstrated gross and microscopic incorporation with the host, including a tendon-like structure, aligned collagen fibers, fibroblast-like cells, and no clear graft-host distinction. Cellular infiltration ranged from 5% to 14% (central graft) to 65% to 92% (sutured attachment points). Neovascularization and active graft remodeling were confirmed histologically. LEVEL OF EVIDENCE: V, case report.


Assuntos
Derme Acelular , Lesões do Manguito Rotador/cirurgia , Manguito Rotador/cirurgia , Luxação do Ombro/cirurgia , Transplante de Pele , Idoso , Aloenxertos , Cartilagem/patologia , Colágeno/química , Feminino , Fibroblastos/metabolismo , Fibrocartilagem/patologia , Humanos , Imageamento por Ressonância Magnética , Osteonecrose/patologia , Fenazinas/farmacologia , Período Pré-Operatório , Dor de Ombro , Tendões/cirurgia , Transplante Homólogo
15.
Mikrochim Acta ; 186(7): 430, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31187249

RESUMO

A photoelectrochemical (PEC) method is described for aptamer-based detection of ofloxacin (OFL). It is making use of a TiO2 nanotube array (NTA) that is sensitized with a structure composed of polydopamine and silver sulfide nanoparticles. The NTA were prepared by a two-step synthetic method. First, the TiO2 nanotube electrode was covered with Ag2S nanoparticles via successive ionic layer adsorption and reaction strategy. Next, they were coated with a thin film of polydopamine (PDA) by in-situ polymerization. The inorganic/organic nanocomposites exhibit distinctly enhanced visible-light PEC activity. This was exploited to fabricate a PEC aptasensor. The PDA film serves as both the sensitizer for charge separation and as a support to bind the aptamer against OFL. The aptasensor undergoes a decrease in photocurrent due to the formation of the aptamer-OFL complex. Under the optimized conditions and at a typical working potential of 0 V (vs. Hg/Hg2Cl2), the NTA has a linear response in the 5.0 pM to 100 nM OFL concentration range and a 0.75 pM detection limit (at S/N = 3). The aptasensor was successfully applied to the determination of OFL in spiked milk samples. Graphical abstract Schematic illustration for the preparation and mechanism of the photoelectrochemical aptasensor for ofloxacin. TiO2 NTs: TiO2 nanotube arrays; PDA: polydopamine; MCH: 6-mercapto-1-hexanol; OFL: ofloxacin; PEC: photoelectrochemistry; CB: conduction band; VB: valence band; LUMO: the lowest unoccupied molecular orbital; HOMO: the highest occupied molecular orbital; AA: ascorbic acid.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotubos/química , Ofloxacino/análise , Animais , Aptâmeros de Nucleotídeos/metabolismo , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Contaminação de Alimentos/análise , Indóis/química , Indóis/efeitos da radiação , Luz , Limite de Detecção , Leite/química , Nanotubos/efeitos da radiação , Ofloxacino/metabolismo , Polímeros/química , Polímeros/efeitos da radiação , Reprodutibilidade dos Testes , Compostos de Prata/química , Titânio/química
16.
Mikrochim Acta ; 185(3): 161, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29594706

RESUMO

A visible-light driven photoelectrochemical (PEC) aptasensor is described that is capable of detecting chloramphenicol (CAP). It is based on the use of a TiO2 based nanorod array (NRA) sensitized with Eu(III)-doped CdS quantum dots. The NRA absorbs visible-light and while strongly depressing the recombination of photogenerated charges, thereby improving photo-to-current conversion efficiency. The introduction of Eu(III) ions promotes the charge transformation and utilization, and this results in a further increase of photocurrent. The NRA was employed as the photoactive material for the fabrication of a PEC aptasensor. CAP-binding aptamers were immobilized on a fluorine-doped tin oxide (FTO) electrode that was modified with the NRA. The aptasensor was applied to the determination of CAP by monitoring the decrease in photocurrent (at a typical voltage of 0 V) that is caused by the formation of the aptamer-CAP complex. Under optimal conditions, the response is linear in the 1.0 pM to 3.0 nM CAP concentration range, with a detection limit of 0.36 pM (at S/N = 3). The method was applied to the determination of CAP in spiked milk samples where it gave satisfactory results. Graphical abstract Schematic presentation of the fabrication of a visible-light driven photoelectrochemical aptasensor based on the use of a TiO2 nanorod array sensitized with Eu(III)-doped CdS quantum dots. It was applied to the determination of chloramphenicol with good selectivity and high sensitivity. TiO2 NRA: TiO2 nanorod array; FTO: fluorine-doped tin oxide; CdS:Eu3+ QDs: Eu(III)-doped CdS quantum dots; BSA: bovine serum albumin; CAP: chloramphenicol.

17.
Cell Tissue Bank ; 18(3): 403-411, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28455604

RESUMO

Human acellular dermal matrices (ADMs) are used successfully in a variety of procedures, including sports medicine related, wound repair, and breast reconstructions, but the mechanism of repair is still not fully understood. An opportunity to explore this mechanism presented itself when a patient experienced a rerupture of the native tendon due to a fall that occurred 2 months after undergoing an Achilles tendon repair using Matracell treated ADM. The ADM was removed and an extensive histology analysis was performed on the tissue. Additionally, a literature review was conducted to determine the mechanism of ADM integration into the tendon structure and explore if differences in this mechanism exist for different types of human ADMS. The histology analysis demonstrated that the healing process during a tendon reconstruction procedure is similar to that of wound healing. Furthermore, the literature review showed that differences exist in the mechanism for integration among various human ADMs and that these differences may be due to variances in the methods and technologies that manufactures use to process human ADMs.


Assuntos
Derme Acelular , Tendão do Calcâneo/lesões , Tendão do Calcâneo/fisiologia , Tendão do Calcâneo/ultraestrutura , Adulto , Feminino , Humanos , Mamoplastia , Cicatrização
18.
Adv Skin Wound Care ; 29(9): 399-406, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27538107

RESUMO

OBJECTIVE: The purpose of this study was to examine the characteristics of a cryopreserved split-thickness skin allograft produced from donated human skin and compare it with fresh, unprocessed human split-thickness skin. BACKGROUND: Cutaneous wound healing is a complex and organized process, where the body re-establishes the integrity of the injured tissue. However, chronic wounds, such as diabetic or venous stasis ulcers, are difficult to manage and often require advanced biologics to facilitate healing. An ideal wound care product is able to directly influence wound healing by introducing biocompatible extracellular matrices, growth factors, and viable cells to the wound bed. MATERIALS AND METHODS: TheraSkin (processed by LifeNet Health, Virginia Beach, Virginia, and distributed by Soluble Systems, Newport News, Virginia) is a minimally manipulated, cryopreserved split-thickness human skin allograft, which contains natural extracellular matrices, native growth factors, and viable cells. The authors characterized TheraSkin in terms of the collagen and growth factor composition using ELISA, percentage of apoptotic cells using TUNEL analysis, and cellular viability using alamarBlue assay (Thermo Fisher Scientific, Waltham, Massachusetts), and compared these characteristics with fresh, unprocessed human split-thickness skin. RESULTS: It was found that the amount of the type I and type III collagen, as well as the ratio of type I to type III collagen in TheraSkin, is equivalent to fresh unprocessed human split-thickness skin. Similar quantities of vascular endothelial growth factor, insulinlike growth factor 1, fibroblast growth factor 2, and transforming growth factor ß1 were detected in TheraSkin and fresh human skin. The average percent of apoptotic cells was 34.3% and 3.1% for TheraSkin and fresh skin, respectively. CONCLUSIONS: Cellular viability was demonstrated in both TheraSkin and fresh skin.


Assuntos
Criopreservação/métodos , Transplante de Pele/métodos , Pele Artificial , Ferimentos e Lesões/terapia , Materiais Biocompatíveis , Humanos , Retalhos Cirúrgicos , Transplante Autólogo , Cicatrização
19.
Cell Tissue Bank ; 16(2): 249-59, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25163609

RESUMO

Decellularized human dermis has been used for a number of clinical applications including wound healing, soft tissue reconstruction, and sports medicine procedures. A variety of methods exist to prepare this useful class of biomaterial. Here, we describe a decellularization technology (MatrACELL(®)) utilizing a non-denaturing anionic detergent, N-Lauroyl sarcosinate, and endonuclease, which was developed to remove potentially immunogenic material while retaining biomechanical properties. Effective decellularization was demonstrated by a residual DNA content of ≤4 ng/mg of wet weight which represented >97 % DNA removal compared to unprocessed dermis. Two millimeter thick MatrACELL processed human acellular dermal matrix (MH-ADM) exhibited average ultimate tensile load to failure of 635.4 ± 199.9 N and average suture retention strength of 134.9 ± 55.1 N. Using an in vivo mouse skin excisional model, MH-ADM was shown to be biocompatible and capable of supporting cellular and vascular in-growth. Finally, clinical studies of MH-ADM in variety of applications suggest it can be an appropriate scaffold for wound healing, soft tissue reconstruction, and soft tissue augmentation.


Assuntos
Derme/citologia , Endonucleases/metabolismo , Cicatrização/fisiologia , Animais , Materiais Biocompatíveis/farmacologia , Detergentes/farmacologia , Humanos , Transplante de Pele/métodos
20.
Cell Immunol ; 289(1-2): 185-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24841857

RESUMO

Pro-inflammatory macrophages are involved in vascular inflammation and serve as the major effector cells in the pathophysiology of atherosclerosis. Phosphatidylcholine (PC) is a major phospholipid moiety affixed to oxidized low-density lipoprotein (oxLDL) and thought to play important roles in the development of atherosclerosis. In this study we described that a bioactive lipid derivative, lysophosphatidylcholine (lysoPC), generated from hydrolysis of the PC moiety of oxidized LDL, promoted and stabilized a strong M1 phenotype in macrophage polarization. Another derivative, 9-hydroxyoctadecadienoic acid (9-HODE), did not show the similar biological function. Blockade of G protein coupled receptor, G2A, which mediates the signal transduction of lysoPC, diminished the effects of lysoPC on the macrophage polarization toward M1 phenotype. The results provide insights into the new mechanism on how oxidized LDL participates in tissue inflammation in atherosclerosis.


Assuntos
Aterosclerose/imunologia , Inflamação/imunologia , Lisofosfatidilcolinas/imunologia , Macrófagos/imunologia , Proteínas de Ciclo Celular/genética , Diferenciação Celular/imunologia , Polaridade Celular , Células Cultivadas , Endotélio Vascular/imunologia , Ácidos Graxos Insaturados/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Lipoproteínas LDL/imunologia , Interferência de RNA , RNA Interferente Pequeno , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/imunologia
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