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1.
Acta Biomater ; 181: 235-248, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38692469

RESUMO

Bacterial infection poses a significant impediment in wound healing, necessitating the development of dressings with intrinsic antimicrobial properties. In this study, a multilayered wound dressing (STPU@MTAI2/AM1) was reported, comprising a surface-superhydrophobic treated polyurethane (STPU) sponge scaffold coupled with an antimicrobial hydrogel. A superhydrophobic protective outer layer was established on the hydrophilic PU sponge through the application of fluorinated zinc oxide nanoparticles (F-ZnO NPs), thereby resistance to environmental contamination and bacterial invasion. The adhesive and antimicrobial inner layer was an attached hydrogel (MTAI2/AM1) synthesized through the copolymerization of N-[2-(methacryloyloxy)ethyl]-N, N, N-trimethylammonium iodide and acrylamide, exhibits potent adherence to dermal surfaces and broad-spectrum antimicrobial actions against resilient bacterial strains and biofilm formation. STPU@MTAI2/AM1 maintained breathability and flexibility, ensuring comfort and conformity to the wound site. Biocompatibility of the multilayered dressing was demonstrated through hemocompatibility and cytocompatibility studies. The multilayered wound dressing has demonstrated the ability to promote wound healing when addressing MRSA-infected wounds. The hydrogel layer demonstrates no secondary damage when peeled off compared to commercial polyurethane sponge dressing. The STPU@MTAI2/AM1-treated wounds were nearly completely healed by day 14, with an average wound area of 12.2 ± 4.3 %, significantly lower than other groups. Furthermore, the expression of CD31 was significantly higher in the STPU@MTAI2/AM1 group compared to other groups, promoting angiogenesis in the wound and thereby contributing to wound healing. Therefore, the prepared multilayered wound dressing presents a promising therapeutic candidate for the management of infected wounds. STATEMENT OF SIGNIFICANCE: Healing of chronic wounds requires avoidance of biofouling and bacterial infection. However developing a wound dressing which is both anti-biofouling and antimicrobial is a challenge. A multilayered wound dressing with multifunction was developed. Its outer layer was designed to be superhydrophobic and thus anti-biofouling, and its inner layer was broad-spectrum antimicrobial and could inhibit biofilm formation. The multilayered wound dressing with adhesive property could easily be removed from the wound surface preventing the cause of secondary damage. The multilayered wound dressing has demonstrated good abilities to promote MRSA-infected wound healing and presents a viable treatment for MRSA-infected wound.


Assuntos
Bandagens , Hidrogéis , Interações Hidrofóbicas e Hidrofílicas , Poliuretanos , Poliuretanos/química , Poliuretanos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Humanos , Camundongos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
2.
Acta Biomater ; 171: 428-439, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37716478

RESUMO

The non-fouling condition, bacteria-free environment and suitable moisture at wound site are crucial for chronic wound healing. However, it remains highly meaningful yet challenging to develop wound dressings that can simultaneously achieve these desirable functions. In this work, a kind of multifunctional Janus polyurethane sponge (Janus-PU) was designed and fabricated by coating near-infrared (NIR)-responsive and superhydrophobic nanoparticles (F-ZnO@Ag NPs) on one surface of sponge. The nano-functionalized outer layer can endow Janus-PU with superhydrophobic antifouling property for preventing bacterial colonization and broad-spectrum antibacterial activity due to the presence of Ag NPs. Especially, the synergistic combination of asymmetric structure and strong NIR photothermal effect can impart Janus-PU with NIR-controlled unidirectional exudate removal, thus achieving an optimal wetting environment for wound healing. The mice full-thickness skin acute wounds treated with Janus-PU under NIR irradiation showed superior anti-infection and healing effect compared to the commercial dressings. Significantly, the treatment using Janus-PU with NIR irradiation can accelerate the recovery of methicillin-resistant Staphylococcus aureus (MRSA)-infected diabetic chronic wounds due to the synergistic effect of antibiofouling, antibacterial and exudate-managing. The Janus-PU as a promising multifunctional dressing can prevent bacterial invasion and create an appropriate environment for wound healing, providing an effective solution for intractable wounds and infections. STATEMENT OF SIGNIFICANCE: The development of advanced wound dressings to ensure non-fouling condition, bacteria-free environment and suitable moisture is crucial for chronic wound healing. However, it remains a considerable challenge to simultaneously integrate antibiofouling, antibacterial and exudate-managing properties into a single dressing. In this work, we developed a kind of multifunctional Janus polyurethane sponge (Janus-PU) by a single-sided superhydrophobic modification strategy, which can simultaneously achieve superhydrophobic antifouling property, effective broad-spectrum antibacterial and near-infrared controlled exudate removal. The Janus-PU designed herein can not only create an optimal environment for accelerated wound healing, but also avoid frequent dressing replacement, thus providing an ideal material system for intractable wounds and infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Poliuretanos , Camundongos , Animais , Poliuretanos/farmacologia , Poliuretanos/química , Cicatrização , Bactérias , Antibacterianos/farmacologia , Antibacterianos/química , Bandagens/microbiologia
3.
HLA ; 101(3): 318-320, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36254745

RESUMO

The novel KIR3DL1*01507 allele differs from the closest allele KIR3DL1*01502 by a single synonymous mutation.


Assuntos
Receptores KIR3DL1 , Humanos , Alelos , Sequência de Bases , População do Leste Asiático , Teste de Histocompatibilidade , Receptores KIR3DL1/genética
4.
Int J Biol Sci ; 14(12): 1696-1708, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416384

RESUMO

Endothelial dysfunction and excessively stimulated autophagy, often caused by oxidant injury or inflammation, will lead to atherosclerosis development and progression in diabetes. The aim of this study is to investigate the protective effect of glucagon-like peptide-1 (GLP-1) treatment on preventing oxidative stress-induced endothelial dysfunction and excessively stimulated autophagy. Treatment of endothelial cells with GLP-1 significantly attenuated oxidative stress-induced endothelial dysfunction and autophagy, which was associated with the reduction of intracellular reactive oxygen species (ROS) levels. These protective effects of GLP-1 were likely mediated by reducing phosphorylation of ERK1/2. We further demonstrated that GLP-1 treatment could reverse downregulation of epigenetic factor histone deacetylase 6 (HDAC6), a downstream molecular of the EKR1/2, induced by oxidant injury. In conclusion, our results suggest that GLP-1 produces a protective effect on endothelial cells from oxidant injury by preventing endothelial dysfunction and autophagy, which may be dependent on restoring HDAC6 through a GLP-1R-ERK1/2-dependent manner.


Assuntos
Células Endoteliais/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Células Endoteliais/patologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/antagonistas & inibidores , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Desacetilase 6 de Histona/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
5.
Med Sci Monit ; 24: 4254-4261, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29925829

RESUMO

BACKGROUND Cytokeratin 19 (CK19) is a typical epithelial marker. In this study, we determined whether epidermal growth factor (EGF) or basic fibroblast growth factor (bFGF) could enhance CK19 expression in adipose-derived stem cells (ADSCs), thereby inducing the differentiation of ADSCs into epithelial-like cells. MATERIAL AND METHODS ADSCs were isolated from perinephric fat, and the expression of CD29, CD90, and CD105 was confirmed. Following isolation, ADSCs were cultured in static medium or medium containing EGF or bFGF. RESULTS Flow cytometry revealed that EGF and bFGF could alter mesenchymal stem cell markers as well as the cell cycle of ADSCs. Western blotting and immunofluorescence revealed that after 14 days, EGF treatment enhanced the expression of CK19 in ADSCs. CONCLUSIONS Our findings offer important insight for the clinical use of ADSCs in the generation of epithelial-like cells in the future.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Queratina-19/biossíntese , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Fator 2 de Crescimento de Fibroblastos/farmacologia , Queratina-19/genética , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Ratos , Células-Tronco/citologia
6.
FASEB J ; 31(6): 2405-2417, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28209773

RESUMO

Mannan binding lectin (MBL), initially reported to activate the complement pathway, is also known to be involved in the pathogenesis of autoimmune diseases. We report a thus far unknown function of MBL as a suppressor of T-cell activation. MBL markedly inhibited T-cell proliferation induced by anti-CD3 and anti-CD28 antibodies. Moreover, the presence of MBL during T-cell priming interfered with proximal T-cell receptor signaling by decreasing phosphorylation of Lck, ZAP-70, and LAT. MBL bound to T cells through interaction between the collagen-like region of MBL and calreticulin (CRT) expressed on the T-cell surface. The neutralizing antibody against CRT abrogated MBL-mediated suppression of T-cell proliferation, suggesting that MBL down-modulates T-cell proliferation via cell surface CRT. We further demonstrated that the feature of MBL-mediated T-cell suppression is shared by other serum collectins (e.g., C1q and collectin 11). The concentrations of MBL correlated negatively with in vivo T-cell activation status in patients with early-stage silicosis. Furthermore, MBL efficiently inhibited activation and proliferation of autoreactive T cells derived from patients with silicosis, indicating that MBL serves as a negative feedback control of the T-cell responses.-Zhao, N., Wu, J., Xiong, S., Zhang, L., Lu, X., Chen, S., Wu, Q., Wang, H., Liu, Y., Chen, Z., Zuo, D. Mannan-binding lectin, a serum collectin, suppresses T-cell proliferation via direct interaction with cell surface calreticulin and inhibition of proximal T-cell receptor signaling.


Assuntos
Calreticulina/metabolismo , Proliferação de Células/fisiologia , Leucócitos Mononucleares/metabolismo , Lectina de Ligação a Manose/metabolismo , Linfócitos T/fisiologia , Calreticulina/genética , Pontos de Checagem do Ciclo Celular , Regulação da Expressão Gênica/fisiologia , Humanos , Receptores de Antígenos de Linfócitos T , Transdução de Sinais , Silicose
7.
J Immunol Methods ; 436: 16-21, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27262264

RESUMO

sDC-SIGN is the soluble form of dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN, CD209), which is a molecule involved with pathogen recognition and immune regulation. However, there is no commercially available ELISA kit for detecting human sDC-SIGN, and the normal range of this molecule is unknown. Here, we describe an ELISA for detecting human sDC-SIGN with high specificity. First, sDC-SIGN protein was expressed and purified. Monoclonal and polyclonal antibodies were then raised against the purified protein and subsequently characterized. A sandwich ELISA was developed using polyclonal antibodies specific for sDC-SIGN for capture and a biotin-labeled monoclonal antibody specific for sDC-SIGN for detection of protein. This method has sensitivity up to 0.2 ng/ml. Using this ELISA, we found that the concentration of sDC-SIGN in sera of healthy volunteers ranges from 0-319 ng/ml with a mean concentration of 27.14 ng/ml. Interestingly, the concentration of sDC-SIGN in sera from patients with cancer or chronic hepatitis B virus (CHB) infection was lower than that of health controls. The mean concentrations of sDC-SIGN in cancer patients and chronic hepatitis B virus infection patients were 3.2 ng/ml and 3.8 ng/ml, respectively. We developed a sandwich ELISA for detecting human sDC-SIGN and demonstrated its use by assessing sera concentrations of sDC-SIGN in patients with cancer and chronic CHB infection compared to that of healthy controls.


Assuntos
Moléculas de Adesão Celular/isolamento & purificação , Células Dendríticas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Hepatite B Crônica/sangue , Lectinas Tipo C/isolamento & purificação , Neoplasias/sangue , Receptores de Superfície Celular/isolamento & purificação , Animais , Anticorpos Monoclonais/imunologia , Estudos de Casos e Controles , Moléculas de Adesão Celular/sangue , Feminino , Hepatite B Crônica/diagnóstico , Humanos , Lectinas Tipo C/sangue , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/diagnóstico , Coelhos , Receptores de Superfície Celular/sangue , Sensibilidade e Especificidade
8.
Transfus Apher Sci ; 53(3): 315-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26141516

RESUMO

BACKGROUND: The assumption that the level of safety of voluntary non-remunerated donors is significantly higher than that of family replacement donors is supported by global data without stratifying for first-time or repeat volunteer, or according to age, but the viral marker prevalence between replacement donors and first-time voluntary non-remunerated donors is similar. MATERIALS AND METHODS: From 2006 to 2013, replacement and voluntary donors were respectively recruited by the hospitals and the Center Blood Station in Zhaoqing, Guangdong, according to the existing procedures, and all the donors were screened for hepatitis B virus (HBV) surface antigen (HBsAg), antibodies against hepatitis C virus (anti-HCV), human immunodeficiency virus (anti-HIV) (1 + 2) and Treponema pallidum (anti-TP) by the enzyme immunoassays (EIAs), and alanine aminotransferase (ALT) in the Center Blood Station by kinetic analysis method. The risk factors related to blood safety were analyzed by Binary logistic regression analysis. RESULTS: Between 252,202 volunteers and 2771 replacement donors, the prevalences of ALT > 40 U/L and anti-HIV (4.88% and 0.01% vs 4.44% and 0.07%, respectively) were not significantly different. The prevalences of HBsAg, anti-HCV and anti-syphilis in replacement group were higher than those in voluntary group, which were related to donor's sex, age and donation time. Overall prevalence of serological markers was higher in male replacement donors than in female, and in replacement donor over 30 years than in those below 30 years, but the positive prevalence in repeated replacement donors was lower than that in first-time replacement donors. CONCLUSIONS: With appropriate intervention measures, such as pre-donor screening and other donor selection policy, replacement donors and voluntary donors provide a similar level of viral safety. Our donor selection policy in future should focus on retaining both young replacement and young voluntary donors as repeat donors and promoting the donation proportion of females, which will improve blood safety.


Assuntos
Doadores de Sangue , Segurança do Sangue , Seleção do Doador , Hepatite B/sangue , Hepatite C/sangue , Sífilis/sangue , Adulto , China/epidemiologia , Feminino , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Humanos , Masculino , Sífilis/epidemiologia
9.
Sensors (Basel) ; 14(4): 6144-64, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24686728

RESUMO

Cloud computing is changing the ways software is developed and managed in enterprises, which is changing the way of doing business in that dynamically scalable and virtualized resources are regarded as services over the Internet. Traditional manufacturing systems such as supply chain management (SCM), customer relationship management (CRM), and enterprise resource planning (ERP) are often developed case by case. However, effective collaboration between different systems, platforms, programming languages, and interfaces has been suggested by researchers. In cloud-computing-based systems, distributed resources are encapsulated into cloud services and centrally managed, which allows high automation, flexibility, fast provision, and ease of integration at low cost. The integration between physical resources and cloud services can be improved by combining Internet of things (IoT) technology and Software-as-a-Service (SaaS) technology. This study proposes a new approach for developing cloud-based manufacturing systems based on a four-layer SaaS model. There are three main contributions of this paper: (1) enterprises can develop their own cloud-based logistic management information systems based on the approach proposed in this paper; (2) a case study based on literature reviews with experimental results is proposed to verify that the system performance is remarkable; (3) challenges encountered and feedback collected from T Company in the case study are discussed in this paper for the purpose of enterprise deployment.

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