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1.
BMC Cancer ; 23(1): 1257, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38124049

RESUMO

PURPOSE: To explore the potential role of signal transducer and activator of transcription 5A (STAT5A) in the metastasis of breast cancer, and its mechanism of regulation underlying. METHODS AND RESULTS: TCGA datasets were used to evaluate the expression of STAT5A in normal and different cancerous tissues through TIMER2.0, indicating that STAT5A level was decreased in breast cancer tissues compared with normal ones. Gene Set Enrichment Analysis predicted that STAT5A was associated with the activation of immune cells and cell cycle process. We further demonstrated that the infiltration of immune cells was positively associated with STAT5A level. Influorescence staining revealed the expression and distribution of F-actin was regulated by STAT5A, while colony formation assay, wound healing and transwell assays predicted the inhibitory role of STAT5A in the colony formation, migratory and invasive abilities in breast cancer cells. In addition, overexpression of the Notch3 intracellular domain (N3ICD), the active form of Notch3, resulted in the increased expression of STAT5A. Conversely, silencing of Notch3 expression by siNotch3 decreased STAT5A expression, supporting that STAT5A expression is positively associated with Notch3 in human breast cancer cell lines and breast cancer tissues. Mechanistically, chromatin immunoprecipitation showed that Notch3 was directly bound to the STAT5A promoter and induced the expression of STAT5A. Moreover, overexpressing STAT5A partially reversed the enhanced mobility of breast cancer cells following Notch3 silencing. Low expression of Notch3 and STAT5A predicted poorer prognosis of patients with breast cancer. CONCLUSION: The present study demonstrates that Notch3 inhibits metastasis in breast cancer through inducing transcriptionally STAT5A, which was associated with tumor-infiltrating immune cells, providing a novel strategy to treat breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais/genética , Imunoprecipitação da Cromatina , Receptor Notch3/genética , Proteínas Supressoras de Tumor/genética
2.
Int Heart J ; 62(2): 381-389, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33731514

RESUMO

Extracellular vesicles (EV) that are derived from endothelial progenitor cells (EPC) have been determined to be a novel therapy for acute myocardial infarction, with a promise for immediate "off-the-shelf" delivery. Early experience suggests delivery of EVs from allogeneic sources is safe. Yet, clinical translation of this therapy requires assurances of both EV stability following cryopreservation and absence of an adverse immunologic response to EVs from allogeneic donors. Thus, more bioactivity studies on allogeneic EVs after cold storage are necessary to establish quality standards for its widespread clinical use. Thus, in this study, we aimed to demonstrate the safety and efficacy in delivering cryopreserved EVs in allogeneic recipients as a therapy for acute myocardial infarction.In this present study, we have analyzed the cardioprotective effects of allogeneic EPC-derived EVs after storage at -80°C for 2 months, using a shear-thinning gel (STG) as an in vivo delivery vehicle. EV size, proteome, and nucleic acid cargo were observed to remain steady through extended cryopreservation via nanoparticle tracking analysis, mass spectrometry, and nanodrop analysis, respectively. Fresh and previously frozen EVs in STG were delivered intramyocardially in a rat model of myocardial infarction (MI), with both showing improvements in contractility, angiogenesis, and scar thickness in comparison to phosphate-buffered saline (PBS) and STG controls at 4 weeks post-MI. Pathologic analyses and flow cytometry revealed minimal inflammatory and immune upregulation upon exposure of tissue to EVs pooled from allogeneic donor cells.Allogeneic EPC-EVs have been known to elicit minimal immune activity and retain therapeutic efficacy after at least 2 months of cryopreservation in a post-MI model.


Assuntos
Células Progenitoras Endoteliais/citologia , Vesículas Extracelulares/patologia , Transplante de Células-Tronco Hematopoéticas/métodos , Infarto do Miocárdio/terapia , Miócitos Cardíacos/patologia , Animais , Células Cultivadas , Criopreservação , Modelos Animais de Doenças , Humanos , Infarto do Miocárdio/patologia , Ratos
3.
Bioconjug Chem ; 29(4): 905-913, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29406696

RESUMO

Biomimetic hydrogels fabricated from biologically derived polymers, such as hyaluronic acid (HA), are useful for numerous biomedical applications. Due to the dynamic nature of biological processes, it is of great interest to synthesize hydrogels with dynamically tunable network properties where various functions (e.g., cargo delivery, mechanical signaling) can be changed over time. Among the various stimuli developed to control hydrogel properties, light stands out for its exquisite spatiotemporal control; however, most light-based chemistries are unidirectional in their ability to manipulate network changes. Here, we report a strategy to reversibly modulate HA hydrogel properties with light, using supramolecular cross-links formed via azobenzene bound to ß-cyclodextrin. Upon isomerization with 365 nm or 400-500 nm light, the binding affinity between azobenzene and ß-cyclodextrin changed and altered the network connectivity. The hydrogel mechanical properties depended on both the azobenzene modification and isomeric state (lower for cis state), with up to a 60% change in storage modulus with light exposure. Furthermore, the release of a fluorescently labeled protein was accelerated with light exposure under conditions that were cytocompatible to encapsulated cells. These results indicate that the developed hydrogels may be suitable for applications in which temporal regulation of material properties is important, such as drug delivery or mechanobiology studies.


Assuntos
Compostos Azo/química , Materiais Biomiméticos/química , Preparações de Ação Retardada/química , Ácido Hialurônico/química , Hidrogéis/química , beta-Ciclodextrinas/química , Animais , Bovinos , Liberação Controlada de Fármacos , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/farmacocinética , Isomerismo , Luz , Teste de Materiais , Camundongos , Células NIH 3T3 , Soroalbumina Bovina/administração & dosagem , Soroalbumina Bovina/farmacocinética
4.
Soft Matter ; 12(37): 7839-7847, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27714343

RESUMO

Macromolecular interactions are used to form supramolecular assemblies, including through the interaction of guest-host chemical pairs. Microstructural heterogeneity has been observed within such physical hydrogels; yet, systematic investigation of the microstructure and its determining inputs are lacking. Herein, we investigated the hierarchical self-assembly of hyaluronic acid (HA) modified by the guest-host pair adamantane (Ad-HA, guest) and ß-cyclodextrin (CD-HA, host), as well as with methacrylate groups to both tether fluorescent agents and to covalently stabilize the material structure. We observed microporous materials in the hydrated state, which temporally arose from initially homogenous hydrogels composed of the two polymers. Independent fluorescent labeling of Ad-HA and CD-HA demonstrated spatiotemporal co-localization, indicative of guest-host polymer condensation on the microscale. The hydrogel void fractions and pore diameters were independently tuned through incubation time (0-7 days), polymer concentration (1.25-10 wt%), and polymer modification (25-50% Ad-HA modification). Void fractions as great as 93.3 ± 2.4% were achieved and pore diameters ranged from 2.1 ± 0.5 to 1025.4 ± 209.4 µm. The segregation of discrete solid and solute phases was measured with both atomic force microscopy and diffusive microparticle tracking analysis, where the solute phase contained only dilute polymer. The study represents a systematic investigation of hierarchical self-assembly in binary associating hydrogels, and provides insights on mechanisms that control microstructure within supramolecular hydrogels.

5.
Environ Sci Pollut Res Int ; 30(11): 29300-29320, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36414890

RESUMO

Based on the relationship between industrial agglomeration, green finance development, and carbon emissions, some relevant theoretical hypotheses are proposed, and this paper employs the combination of spatial Durbin model and panel threshold model to empirically test data from 30 provincial regions in China from 2006 to 2019. The results show that the agglomeration of high energy-consuming industries has an inverse U-curve relationship with carbon emission intensity, and the development of green finance will inhibit the growth of carbon emission intensity. There are significant spatial characteristics of high energy-consuming industrial agglomeration, green financial development, and carbon emissions. And the intensity of local carbon emissions will be influenced by the agglomeration of high energy-consuming industrial agglomeration and green financial development in local and neighboring areas. Moreover, green financial development plays a moderating role in the relationship between high energy-consuming industrial agglomeration and carbon emissions, and the role of high energy-consuming industrial agglomeration and green financial development on carbon emissions has a threshold effect due to the mismatch between the two developments. Under different levels of green financial development, the influence of high energy-consuming industrial agglomeration on carbon emissions varies widely, and green financial development helps to suppress the negative impact of high energy-consuming industrial agglomeration on carbon emissions. Accordingly, we argue that inter-regional joint prevention and control mechanism should be established for pollution control. And China should build more effective high energy-consuming industrial clusters to make them play an active role in reducing emissions. At the same time, China should accelerate the construction of green finance, strengthen the disclosure and transparency of green financial information, and establish a joint mechanism for the development of inter-regional green finance, so that it can contribute to regional industrial transformation and pollution control.


Assuntos
Carbono , Revelação , China , Poluição Ambiental , Indústrias , Desenvolvimento Econômico , Dióxido de Carbono
6.
J AOAC Int ; 105(4): 941-949, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35302611

RESUMO

BACKGROUND: Vancomycin and norvancomycin, as potent antibacterial retention drugs, were used illegally on animals bred for food, which directly affected the quality and safety of animal-derived food, and even harmed human health. OBJECTIVE: A fast analysis method, which was adopted to detect residues of vancomycin and norvancomycin in milk, was implemented on a chromatographic system containing online solid-phase extraction (SPE) device that combined with high-resolution mass spectrometer (HRMS). METHOD: First, the analytes were added to the blank milk sample were extracted with water [containing 0.1% trifluoroacetic acid (TFA)]-acetonitrile (ACN) (8:2, v/v), and then were purified and enriched on a C18-XL column, whereafter eluted from the purification column onto the analytical column (Shiseido Capcell Pak ADME column) for chromatographic separation prior to hybrid quadrupole-Orbitrap (Q-Orbitrap) detection. RESULTS: The results showed that the limit of detection (LOD) for each analyte and the limit of quantitation (LOQ) were 0.15 and 0.5 µg/kg, respectively. The correlation coefficient(s) of vancomycin and norvancomycin ranged from 0 to 200 ng/mL were greater than 0.9983. CONCLUSIONS: These validations reflected that it was suitable for the established method to rapidly analyze vancomycin and norvancomycin residues in milk. HIGHLIGHTS: The method for detecting vancomycin and norvancomycin residues in milk by online SPE combined with LC-HRMS. Online SPE technology realized automation, and the application of HRMS greatly improved the reliability of qualitative and quantitative analyses. The developed method is fast, simple, and reliable; each methodological index can meet requirements of trace analyses of vancomycin and norvancomycin in milk.


Assuntos
Leite , Vancomicina , Animais , Antibacterianos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Leite/química , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Vancomicina/análogos & derivados
7.
Medicine (Baltimore) ; 100(48): e28045, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-35049220

RESUMO

INSTRUCTION: Despite the continuous advancement of liver cancer diagnosis technology and level, there are still nearly two-thirds of patients with primary liver cancer that are already advanced at the time of diagnosis. Ultrasound-guided microwave ablation, as a palliative treatment for intermediate and advanced liver cancer, is currently recognized internationally Standard treatment for patients with unresectable hepatocellular carcinoma. However, recently, some scholars hold that ultrasound-guided microwave ablation does not guarantee complete inactivation of tumor lesions. METHODS/DESIGN: This study will evaluate the safety and effectiveness of ultrasound-guided microwave ablation in patients with advanced hepatocellular carcinoma through retrospective analysis. This study will follow a clinical research method with consecutive enrollment. The overall survival rate, objective tumor remission rate, serum indices and incidence of adverse effects after treatment will be counted for patients. DISCUSSION: At present, there are no good treatment options for intermediate and advanced hepatocellular carcinoma. Therefore, there is a strong demand to explore the individualized multidisciplinary combined treatment model based on ultrasound-guided microwave ablation. TRIAL REGISTRATION: ClinicalTrials.gov, ChiCTR2100052107, Registered on 17 October 2021.


Assuntos
Carcinoma Hepatocelular/terapia , Ablação por Cateter , Neoplasias Hepáticas/terapia , Micro-Ondas/uso terapêutico , Carcinoma Hepatocelular/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção
8.
ACS Biomater Sci Eng ; 7(7): 3209-3220, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34160196

RESUMO

Successful treatment of glioblastoma (GBM) is hampered by primary tumor recurrence after surgical resection and poor prognosis, despite adjuvant radiotherapy and chemotherapy. In search of improved outcomes for this disease, quisinostat appeared as a lead compound in drug screening. A delivery system was devised for this drug and to exploit current clinical methodology: an injectable hydrogel, loaded with both the quisinostat drug and radiopaque gold nanoparticles (AuNP) as contrast agent, that can release these payloads as a response to radiation. This hydrogel grants high local drug concentrations, overcoming issues with current standards of care. Significant hydrogel degradation and quisinostat release were observed due to the radiation trigger, providing high in vitro anticancer activity. In vivo, the combination of radiotherapy and the radiation-induced delivery of quisinostat from the hydrogel, successfully inhibited tumor growth in a mice model bearing xenografted human GBM tumors with a total response rate of 67%. Long-term tolerability was observed after intratumoral injection of the quisinostat loaded hydrogel. The AuNP payload enabled precise image-guided radiation delivery and the monitoring of hydrogel degradation using computed tomography (CT). These exciting results highlight this hydrogel as a versatile imageable drug delivery platform that can be activated simultaneously to radiation therapy and potentially offers improved treatment for GBM.


Assuntos
Glioblastoma , Nanopartículas Metálicas , Glioblastoma/diagnóstico por imagem , Ouro , Humanos , Hidrogéis , Recidiva Local de Neoplasia
9.
Pediatr Crit Care Med ; 11(3): 378-84, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19770787

RESUMO

OBJECTIVE: The goal of this study was to explore the role of communication in building trust between intensivists and parents in the pediatric intensive care unit. METHODS: Semistructured qualitative interviews were administered to English-speaking parents of children who were admitted to the pediatric intensive care unit for at least 48 hrs. Parents were asked about the factors impacting trust and communication in the pediatric intensive care unit. Qualitative data were managed with NVIVO software (QSR International, Southport, UK) and analyzed for themes. RESULTS: Participants were 122 parents (41% black, 40% white). Most parents articulated that communication is integral to building trust. Specifically, parents described that they wanted healthcare workers to communicate in ways that were Honest, Inclusive, Compassionate, Clear and Comprehensive, and Coordinated, which can be summarized using the acronym, HICCC. In addition, nonwhite parents were more likely than white parents to report instances when they felt doctors did not listen to them (p = 0.0083). Parents from minority groups reported instances of self-experienced or observed discrimination in healthcare with greater frequency than white parents. When asked to identify their pediatric intensive care unit doctor, 46% of parents were either unable to do so or named doctors from other hospital departments. CONCLUSIONS: Communication is vital to building trust in the pediatric intensive care unit. Developed from parents' own observations and perspectives, HICCC is an accessible framework that can help doctors to remember what parents value in communication in the acute care setting. In addition, pediatric intensivists would benefit from targeted cultural competency training to reduce physician bias.


Assuntos
Comunicação , Unidades de Terapia Intensiva Pediátrica , Pais/psicologia , Confiança , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Relações Profissional-Família
10.
J Thorac Cardiovasc Surg ; 157(4): 1479-1490, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30579534

RESUMO

OBJECTIVES: The ventricle undergoes adverse remodeling after myocardial infarction, resulting in abnormal biomechanics and decreased function. We hypothesize that tissue-engineered therapy could minimize postischemic remodeling through mechanical stress reduction and retention of tensile myocardial properties due to improved endothelial progenitor cell retention and intrinsic biomechanical properties of the hyaluronic acid shear-thinning gel. METHODS: Endothelial progenitor cells were harvested from adult Wistar rats and resuspended in shear-thinning gel. The constructs were injected at the border zone of ischemic rat myocardium in an acute model of myocardial infarction. Myocardial remodeling, tensile properties, and hemodynamic function were analyzed: control (phosphate-buffered saline), endothelial progenitor cells, shear-thinning gel, and shear-thinning gel + endothelial progenitor cells. Novel high-resolution, high-sensitivity ultrasound with speckle tracking allowed for global strain analysis. Uniaxial testing assessed tensile biomechanical properties. RESULTS: Shear-thinning gel + endothelial progenitor cell injection significantly increased engraftment and retention of the endothelial progenitor cells within the myocardium compared with endothelial progenitor cells alone. With the use of strain echocardiography, a significant improvement in left ventricular ejection fraction was noted in the shear-thinning gel + endothelial progenitor cell cohort compared with control (69.5% ± 10.8% vs 40.1% ± 4.6%, P = .04). A significant normalization of myocardial longitudinal displacement with subsequent stabilization of myocardial velocity with shear-thinning gel + endothelial progenitor cell therapy compared with control was also evident (0.84 + 0.3 cm/s vs 0.11 ± 0.01 cm/s, P = .03). A significantly positive and higher myocardial strain was observed in shear-thinning gel + endothelial progenitor cell (4.5% ± 0.45%) compared with shear-thinning gel (3.7% ± 0.24%), endothelial progenitor cell (3.5% ± 0.97%), and control (8.6% ± 0.3%, P = .05). A resultant reduction in dynamic stiffness was noted in the shear-thinning gel + endothelial progenitor cell cohort. CONCLUSIONS: This novel injectable shear-thinning hyaluronic acid hydrogel demonstrates stabilization of border zone myocardium with reduction in adverse myocardial remodeling and preservation of myocardial biomechanics. The cellular construct provides a normalization of strain measurements and reduces left ventricular dilatation, thus resulting in improvement of left ventricular function.


Assuntos
Células Progenitoras Endoteliais/transplante , Hemodinâmica , Ácido Hialurônico/administração & dosagem , Infarto do Miocárdio/cirurgia , Miocárdio/patologia , Transplante de Células-Tronco/métodos , Função Ventricular Esquerda , Remodelação Ventricular , Animais , Fenômenos Biomecânicos , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Sobrevivência de Enxerto , Hidrogéis , Injeções , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Neovascularização Fisiológica , Ratos Wistar , Recuperação de Função Fisiológica , Estresse Mecânico , Resistência à Tração
11.
Macromol Biosci ; 19(1): e1800248, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30259658

RESUMO

Shear-thinning hydrogels are useful for biomedical applications, from 3D bioprinting to injectable biomaterials. Although they have the appropriate properties for injection, it may be advantageous to decouple injectability from the controlled release of encapsulated therapeutics. Toward this, composites of hydrogels and encapsulated microgels are introduced with microgels that are fabricated via microfluidics. The microgel cross-linker controls degradation and entrapped molecule release, and the concentration of microgels alters composite hydrogel rheological properties. For the treatment of myocardial infarction (MI), interleukin-10 (IL-10) is encapsulated in microgels and released from composites. In a rat model of MI, composites with IL-10 reduce macrophage density after 1 week and improve scar thickness, ejection fraction, cardiac output, and the size of vascular structures after 4 weeks when compared to saline injection. Improvements are also observed with the composite without IL-10 over saline, emphasizing the role of injectable hydrogels alone on tissue repair.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Interleucina-10 , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacocinética , Materiais Biocompatíveis/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Modelos Animais de Doenças , Hidrogéis/química , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Interleucina-10/química , Interleucina-10/farmacocinética , Interleucina-10/farmacologia , Infarto do Miocárdio/metabolismo , Ratos
12.
J Vis Exp ; (147)2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31157790

RESUMO

In recent years, emerging databases were designed to lower the barriers for approaching the intricate cancer genomic datasets, thereby, facilitating investigators to analyze and interpret genes, samples and clinical data across different types of cancer. Herein, we describe a practical operation procedure, taking ID1 (Inhibitor of DNA binding proteins 1) as an example, to characterize the expression patterns of biomarker and survival predictors of breast cancer based on pooled clinical datasets derived from online accessible databases, including ONCOMINE, bcGenExMiner v4.0 (Breast cancer gene-expression miner v4.0), GOBO (Gene expression-based Outcome for Breast cancer Online), HPA (The human protein atlas), and Kaplan-Meier plotter. The analysis began with querying the expression pattern of the gene of interest (e.g., ID1) in cancerous samples vs. normal samples. Then, the correlation analysis between ID1 and clinicopathological characteristics in breast cancer was performed. Next, the expression profiles of ID1 was stratified according to different subgroups. Finally, the association between ID1 expression and survival outcome was analyzed. The operation procedure simplifies the concept to integrate multidimensional data types at the gene level from different databases and test hypotheses regarding recurrence and genomic context of gene alteration events in breast cancer. This method can improve the credibility and representativeness of the conclusions, thereby, present informative perspective on a gene of interest.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Mineração de Dados , Bases de Dados Factuais , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Probabilidade , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida
13.
Transl Oncol ; 11(5): 1259-1270, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30119050

RESUMO

Breast cancer is the second leading cause of cancer death in women worldwide. Incurable metastatic breast disease presents a major clinical challenge and is the main cause of breast cancer-related death. The epithelial-mesenchymal transition (EMT) is a critical early promoter of metastasis. In the present study, we identified a novel role for the inhibitor of DNA binding 2 (Id2), a member of the basic helix-loop-helix protein family, during the EMT of breast cancer. Expression of Id2 was positively correlated with Notch3 in breast cancer cells. Low expression of Id2 and Notch3 was associated with worse distant metastasis-free survival in breast cancer patients. The present study revealed that Id2 activated Notch3 expression by blocking E2A binding to an E-box motif in the Notch3 promoter. The Id2-mediated up-regulation of Notch3 expression at both the mRNA and protein levels resulted in an attenuated EMT, which was associated with reduced motility and matrix invasion of ER-positive and -negative human breast cancer cells and the emergence of E-cadherin expression and reduction in the mesenchymal marker vimentin in triple-negative breast cancer cells. In summary, our findings identified Id2 as a suppressor of the EMT and positive transcriptional regulator of Notch3 in breast cancer. Id2 and Notch3 may serve as novel prognostic markers in a subpopulation of ER-positive breast cancer patients.

14.
Nat Protoc ; 12(8): 1521-1541, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28683063

RESUMO

The design of injectable hydrogel systems addresses the growing demand for minimally invasive approaches for local and sustained delivery of therapeutics. We developed a class of hyaluronic acid (HA) hydrogels that form through noncovalent guest-host interactions, undergo disassembly (shear-thinning) when injected through a syringe and then reassemble within seconds (self-healing) when shear forces are removed. Its unique properties enable the use of this hydrogel system for numerous applications, such as injection in vivo (including with cells and therapeutic molecules) or as a 'bioink' in 3D-printing applications. Here, we describe the functionalization of HA either with adamantanes (guest moieties) via controlled esterification or with ß-cyclodextrins (host moieties) through amidation. We also describe how to modify the HA derivatives with methacrylates for secondary covalent cross-linking and for reaction with fluorophores for in vitro and in vivo imaging. HA polymers are rationally designed from relatively low-molecular-weight starting materials, with the degree of modification controlled, and have matched guest-to-host stoichiometry, allowing the preparation of hydrogels with tailored properties. This procedure takes 3-4 weeks to complete. We detail the preparation and characterization of the guest-host hydrogels, including assessment of their rheological properties, erosion and biomolecule release in vitro. We furthermore demonstrate how to encapsulate cells in vitro and provide procedures for quantitative assessment of in vivo hydrogel degradation by imaging of fluorescently derivatized materials.


Assuntos
Portadores de Fármacos/administração & dosagem , Ácido Hialurônico/administração & dosagem , Hidrogéis/administração & dosagem , Hidrogéis/química , Impressão Tridimensional , Adamantano/metabolismo , Animais , Injeções , Camundongos , beta-Ciclodextrinas/metabolismo
15.
ACS Biomater Sci Eng ; 3(12): 3146-3160, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29250593

RESUMO

Injectable hydrogels have gained popularity as a vehicle for the delivery of cells, growth factors, and other molecules to localize and improve their retention at the injection site, as well as for the mechanical bulking of tissues. However, there are many factors, such as viscosity, storage and loss moduli, and injection force, to consider when evaluating hydrogels for such applications. There are now numerous tools that can be used to quantitatively assess these factors, including for shear-thinning hydrogels because their properties change under mechanical load. Here, we describe relevant rheological tests and ways to measure injection force using a force sensor or a mechanical testing machine toward the evaluation of injectable hydrogels. Injectable, shear-thinning hydrogels can be used in a variety of clinical applications, and as an example we focus on methods for injection into the heart, where an understanding of injection properties and mechanical forces is imperative for consistent hydrogel delivery and retention. We discuss methods for delivery of hydrogels to mouse, rat, and pig hearts in models of myocardial infarction, and compare methods of tissue postprocessing for hydrogel preservation. Our intent is that the methods described herein can be helpful in the design and assessment of shear-thinning hydrogels for widespread biomedical applications.

16.
Oncotarget ; 8(11): 17573-17585, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28407679

RESUMO

The p21-activated kinase 4 (PAK4) is sufficient to transform noncancerous mammary epithelial cells and to form tumors in the mammary glands of mice. The accumulated information suggests that PAK4 might be an oncogenic protein in breast cancer. In this study, we sought to identify the role for PAK4 in breast cancer progression. Immunohistochemical study revealed that high PAK4 expression is associated with larger tumor size, lymph node metastasis, and advanced stage cancer in 93 invasive breast carcinoma patients. Moreover, high PAK4 expression was significantly associated with poor overall and disease-free survival. PAK4 remained an independent adverse prognosticator after univariate and multivariate analysis. Ectopic expression of wild-type PAK4 in MDA-MB-231 cells activated PI3K/AKT signaling and resulted in the enhancement of the cell proliferation, migration, and invasion, whereas PAK4-induced effects were blocked by the PAK4 kinase inhibitor PF- 3758309, PAK4 siRNAs or the PI3K inhibitor LY294002. Furthermore, a kinase-active PAK4 (S474E) strongly induced PI3K/AKT activation, and promoted proliferation, migration and invasion in breast cancer cells. A kinase-inactive PAK4 KD (K350A/K351A) did partially upregulate PI3K/AKT, and promoted invasive phenotype. Taken together, these findings suggest that PAK4-activated PI3K/AKT signaling is both kinase-dependent and -independent, which contributes to breast cancer progression. Thus, our results imply that dual inhibition of PAK4 and PI3K/AKT signaling might be a potential therapeutic approach for breast cancer therapy.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Transformação Celular Neoplásica/metabolismo , Transdução de Sinais/fisiologia , Quinases Ativadas por p21/metabolismo , Adulto , Idoso , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/patologia , Intervalo Livre de Doença , Feminino , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Immunoblotting , Estimativa de Kaplan-Meier , Camundongos , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo
17.
J Thorac Cardiovasc Surg ; 150(5): 1268-76, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26293548

RESUMO

OBJECTIVES: The clinical translation of cell-based therapies for ischemic heart disease has been limited because of low cell retention (<1%) within, and poor targeting to, ischemic myocardium. To address these issues, we developed an injectable hyaluronic acid (HA) shear-thinning hydrogel (STG) and endothelial progenitor cell (EPC) construct (STG-EPC). The STG assembles as a result of interactions of adamantine- and ß-cyclodextrin-modified HA. It is shear-thinning to permit delivery via a syringe, and self-heals upon injection within the ischemic myocardium. This directed therapy to the ischemic myocardial border zone enables direct cell delivery to address adverse remodeling after myocardial infarction. We hypothesize that this system will enhance vasculogenesis to improve myocardial stabilization in the context of a clinically translatable therapy. METHODS: Endothelial progenitor cells (DiLDL(+) VEGFR2(+) CD34(+)) were harvested from adult male rats, cultured, and suspended in the STG. In vitro viability was quantified using a live-dead stain of EPCs. The STG-EPC constructs were injected at the border zone of ischemic rat myocardium after acute myocardial infarction (left anterior descending coronary artery ligation). The migration of the enhanced green fluorescent proteins from the construct to ischemic myocardium was analyzed using fluorescent microscopy. Vasculogenesis, myocardial remodeling, and hemodynamic function were analyzed in 4 groups: control (phosphate buffered saline injection); intramyocardial injection of EPCs alone; injection of the STG alone; and treatment with the STG-EPC construct. Hemodynamics and ventricular geometry were quantified using echocardiography and Doppler flow analysis. RESULTS: Endothelial progenitor cells demonstrated viability within the STG. A marked increase in EPC engraftment was observed 1-week postinjection within the treated myocardium with gel delivery, compared with EPC injection alone (17.2 ± 0.8 cells per high power field (HPF) vs 3.5 cells ± 1.3 cells per HPF, P = .0002). A statistically significant increase in vasculogenesis was noted with the STG-EPC construct (15.3 ± 5.8 vessels per HPF), compared with the control (P < .0001), EPC (P < .0001), and STG (P < .0001) groups. Statistically significant improvements in ventricular function, scar fraction, and geometry were noted after STG-EPC treatment compared with the control. CONCLUSIONS: A novel injectable shear-thinning HA hydrogel seeded with EPCs enhanced cell retention and vasculogenesis after delivery to ischemic myocardium. This therapy limited adverse myocardial remodeling while preserving contractility.


Assuntos
Células Progenitoras Endoteliais/transplante , Ácido Hialurônico/química , Isquemia Miocárdica/cirurgia , Miocárdio/patologia , Regeneração , Alicerces Teciduais , Animais , Movimento Celular , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Ecocardiografia Doppler , Células Progenitoras Endoteliais/metabolismo , Fibrose , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Hidrogéis , Masculino , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Miocárdio/metabolismo , Neovascularização Fisiológica , Ratos Wistar , Recuperação de Função Fisiológica , Fatores de Tempo , Transfecção , Função Ventricular Esquerda , Pressão Ventricular , Remodelação Ventricular , beta-Ciclodextrinas/química
18.
J Cardiovasc Transl Res ; 7(2): 242-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24429838

RESUMO

Hemocompatibility of tissue-engineered vascular grafts remains a major hurdle to clinical utility for small-diameter grafts. Here we assessed the feasibility of using autologous blood outgrowth endothelial cells to create an endothelium via lumenal seeding on completely biological, decellularized engineered allografts prior to implantation in the sheep femoral artery. The 4-mm-diameter, 2- to 3-cm-long grafts were fabricated from fibrin gel remodeled into an aligned tissue tube in vitro by ovine dermal fibroblasts prior to decellularization. Decellularized grafts pre-seeded with blood outgrowth endothelial cells (n = 3) retained unprecedented (>95 %) monolayer coverage 1 h post-implantation and had greater endothelial coverage, smaller wall thickness, and more basement membrane after 9-week implantation, including a final week without anti-coagulation therapy, compared with contralateral non-seeded controls. These results support the use of autologous blood outgrowth endothelial cells as a viable source of endothelial cells for creating an endothelium with biological function on decellularized engineered allografts made from fibroblast-remodeled fibrin.


Assuntos
Implante de Prótese Vascular/instrumentação , Prótese Vascular , Proliferação de Células , Células Endoteliais/transplante , Artéria Femoral/cirurgia , Engenharia Tecidual/métodos , Aloenxertos , Animais , Membrana Basal/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Estudos de Viabilidade , Artéria Femoral/metabolismo , Fibrina/metabolismo , Modelos Animais , Desenho de Prótese , Fluxo Pulsátil , Ovinos , Estresse Mecânico , Fatores de Tempo , Alicerces Teciduais
19.
Front Med ; 6(3): 322-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22843305

RESUMO

The aim of this study was to determine the prevalence of overweight and obese subjects in the Shanghai population of China and its association with undiagnosed hypertension, by taking age, gender and place of residence (urban or suburban) into account. A cross-sectional population-based survey was conducted in 2007. The sample included 13,359 participants aged 15-69 years.Weight, height, and blood pressure were recorded, and information about gender, age and place of residence was obtained. Overweight and obesity prevalence were calculated by the body mass index (BMI) definition recommended by Working Group on Obesity in China (normal weight, 18.5-23.9 kg/m(2); overweight, 24-27.9 kg/m(2); obesity, ≥ 28 kg/m(2)). Undiagnosed hypertension was defined by China criteria in accord with that of WHO-ISH (subjects with systolic pressure ≥ 140 mmHg, and/or diastolic pressure ≥ 90 mmHg). Multiple logistic regression analyses were used to assess the association of overweight or obesity with undiagnosed hypertension by adjusting for age, gender and place of residence. The overall overweight, obesity, and undiagnosed hypertension prevalence were 27.6% (95% CI: 26.8-28.4), 6.6% (95% CI: 6.2-7.0), and 15.5% (95% CI: 14.9-16.1), respectively. Compared to normal weight subjects, the odds ratios (OR) for subjects who were overweight and had hypertension was 2.33 (95% CI: 2.10-2.59); that for obesity and hypertension was 4.27 (95% CI: 3.66-4.99). These data suggest that overweight and obesity prevalence and their association with undiagnosed hypertension are high in our study population.


Assuntos
Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Obesidade/epidemiologia , Obesidade/fisiopatologia , Sobrepeso/epidemiologia , Sobrepeso/fisiopatologia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência
20.
Chinese Journal of School Health ; (12): 1020-1023, 2021.
Artigo em Chinês | WPRIM | ID: wpr-886314

RESUMO

Objective@#To assess the effectiveness of sexual education intervention among seventh grade students, and to provide support tools for sex education for middle school students.@*Methods@#Seventh grade students from six schools in Longnan, Gansu Province were randomly assigned to an intervention group (251 students) and a control group (222 students). After 8 weeks of school based sex education in the intervention group, the results were compared before and after the intervention using self assessment knowledge and attitude scales.@*Results@#The knowledge score in the control group decreased by (2.46±1.21) in the follow up survey compared to the baseline survey. The intervention group scored (30.54±1.34) significantly higher than baseline ( t =22.76, P <0.01). After adjusting the sex ratio to 1∶1, the mean difference between the two groups after the intervention was (27.86±1.87) ( t =14.90, P <0.01). The interaction dit between time and intervention was (33.01±2.50) ( t =13.19, P <0.01) in difference analysis. The intervention effect size Hedge s g on knowledge in the intervention group was 1.27. The proportion of positive attitudes towards sex increased in the intervention group on 12 out of 14 questions, with percentage ranging from 7.5% to 25.9%. At the follow up, the improvement in attitudes towards 12 questions was substantial for girls and 8 questions for boys in the intervention group. The attitude effect size Hedge s g was 0.99 in the intervention group.@*Conclusion@#The implementation of school based sex education is capable of significant improving students sexual knowledge and attitude in the short term.

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