Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Small ; : e2311073, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566548

RESUMO

Immobilization of quantum dots (QDs) on fiber surfaces has emerged as a robust approach for preserving their functional characteristics while mitigating aggregation and instability issues. Despite the advancement, understanding the impacts of QDs on jet-fiber evolution during electrospinning, QDs-fiber interface, and composites functional behavior remains a knowledge gap. The study adopts a high-speed imaging methodology to capture the immobilization effects on the QDs-fiber matrix. In situ observations reveal irregular triangular branches within the QDs-fiber matrix, exhibiting distinctive rotations within a rapid timeframe of 0.00667 ms. The influence of FeQDs on Taylor cone dynamics and subsequent fiber branching velocities is elucidated. Synthesis phenomena are correlated with QD-fiber's morphology, crystallinity, and functional properties. PAN-FeQDs composite fibers substantially reduced (50-70%) nano-fibrillar length and width while their diameter expanded by 17%. A 30% enhancement in elastic modulus and reduction in adhesion force for PAN-FeQDs fibers is observed. These changes are attributed to chemical and physical intertwining between the FeQDs and the polymer matrix, bolstered by the shifts in the position of C≡N and C═C bonds. This study provides valuable insights into the quantum dot-fiber composites by comprehensively integrating and bridging jet-fiber transformation, fiber structure, nanomechanics, and surface chemistry.

2.
Nanoscale ; 16(6): 2983-2992, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38259163

RESUMO

A myocardial infarction (MI), commonly called a heart attack, results in the death of cardiomyocytes (CMs) in the heart. Tissue engineering provides a promising strategy for the treatment of MI, but the maturation of human engineered cardiac tissue (hECT) still requires improvement. Conductive polymers and nanomaterials have been incorporated into the extracellular matrix to enhance the mechanical and electrical coupling between cardiac cells. Here we report a simple approach to incorporate gold nanorods (GNRs) into the fibrin hydrogel to form a GNR-fibrin matrix, which is used as the major component of the extracellular matrix for forming a 3D hECT construct suspended between two flexible posts. The hECTs made with GNR-fibrin hydrogel showed markers of maturation such as higher twitch force, synchronous beating activity, sarcomere maturation and alignment, t-tubule network development, and calcium handling improvement. Most importantly, the GNR-hECTs can survive over 9 months. We envision that the hECT with GNRs holds the potential to restore the functionality of the infarcted heart.


Assuntos
Infarto do Miocárdio , Nanotubos , Humanos , Engenharia Tecidual , Ouro , Miócitos Cardíacos , Matriz Extracelular , Hidrogéis , Infarto do Miocárdio/terapia , Fibrina
3.
PeerJ Comput Sci ; 9: e1209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346682

RESUMO

COVID-19 is now often moderate and self-recovering, but in a significant proportion of individuals, it is severe and deadly. Determining whether individuals are at high risk for serious disease or death is crucial for making appropriate treatment decisions. We propose a computational method to estimate the mortality risk for patients with COVID-19. To develop the model, 4,711 reported cases confirmed as SARS-CoV-2 infections were used for model development. Our computational method was developed using ensemble learning in combination with a genetic algorithm. The best-performing ensemble model achieves an AUCROC (area under the receiver operating characteristic curve) value of 0.7802. The best ensemble model was developed using only 10 features, which means it requires less medical information so that the diagnostic cost may be reduced while the prognostic time may be improved. The results demonstrate the robustness of the used method as well as the efficiency of the combination of machine learning and genetic algorithms in developing the ensemble model.

4.
Cancer Genet ; 276-277: 17-29, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37343507

RESUMO

BACKGROUND: The critical role of the unfolded protein response (UPR) in tumorigenesis is widely acknowledged, yet the precise molecular mechanisms underlying its contribution to breast cancer (BC) have not been fully elucidated. The present study aimed to comprehensively explore the expression characteristics and prognostic significance of UPR-related genes in breast cancer METHODS: The transcriptome and clinical data of breast cancer were acquired from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, respectively. Differential expression analysis was conducted on UPR-related genes, and the resulting genes were employed for consensus clustering analysis. A breast cancer prognosis risk model was constructed using univariate, least absolute shrinkage and selection operator (LASSO), and multivariable Cox regression analyses. Difference in survival outcomes between groups were analyzed Kaplan-Meier survival analysis, and receiver operating characteristic (ROC) curve was used to assess predictive performance. The relationship between the risk model and clinical-pathological characteristics, immune infiltration, immunotherapy response, and drug sensitivity was assessed. RESULTS: Differential expression analysis identified 10 UPR-related genes that were differentially expressed in breast cancer. Using the expression matrix of these genes, two molecular subtypes of breast cancer were characterized, which displayed significant differences in prognostic and immune infiltration characteristics. Drawing from the gene expression profiles that distinguish between the molecular subtypes, a prognostic risk scoring model comprising eight genes was developed. This model stratified BC patients from both the training and validation cohorts into high-risk and low-risk groups. Patients in the low-risk group had better prognoses, while those with advanced clinical stage and T stage exhibited higher risk scores. The high- and low-risk groups exhibited notable disparities in immune cell infiltration and the expression of multiple immune checkpoint-related genes. Additionally, the low-risk group demonstrated elevated immunophenoscore, Merck18, CD274, and CAF scores compared to the high-risk group, along with a lesser sensitivity to chemotherapy drugs. These results suggest that patients within the low-risk group may potentially benefit more from immunotherapy and chemotherapy interventions. CONCLUSIONS: This study developed a novel UPR-derived risk signature, which could robustly predict the survival outcome, immune microenvironment, and chemotherapy response of patients with breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Microambiente Tumoral/genética , Mama , Prognóstico , Fatores de Risco
5.
Nanoscale ; 15(24): 10360-10370, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37291990

RESUMO

Understanding myocytes' spatiotemporal mechanical behavior and viscoelasticity is a long-standing challenge as it plays a critical role in regulating structural and functional homeostasis. To probe the time-dependent viscoelastic behaviors of cardiomyocytes with cross-linked polymer networks, we measure stem cell-derived cardiomyocyte's (hiPSC-CM) deformation, adhesion, and contractility using atomic force microscopy (AFM) nanoindentation, fluidic micropipette, and digital image correlation (DIC). Our results show a cytoplasm load of 7-14 nN, a de-adhesion force of 0.1-1 nN, and an adhesion force between two hiPSC-CMs of 50-100 nN with an interface energy of 0.45 pJ. Based on the load-displacement curve, we model its dynamic viscoelasticity and discover its intimate associations with physiological properties. Cell detaching and contractile modeling demonstrate cell-cell adhesion and beating related strains manifesting viscoelastic behavior, highlighting viscoelasticity plays the primary role in governing hiPSC-CM spatiotemporal mechanics and functions. Overall, this study provides valuable information about the mechanical properties, adhesion behaviors, and viscoelasticity of single hiPSC-CM, shedding light on mechanical-structure relationships and their dynamic responses to mechanical stimuli and spontaneous contraction.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Fenômenos Mecânicos , Microscopia de Força Atômica/métodos , Adesão Celular
6.
ACS Appl Mater Interfaces ; 15(20): 24197-24208, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37178192

RESUMO

Ashby's map's role in rationally selecting materials for optimal performance is well-established in traditional engineering applications. However, there is a major gap in Ashby's maps in selecting materials for tissue engineering, which are very soft with an elastic modulus of less than 100 kPa. To fill the gap, we create an elastic modulus database to effectively connect soft engineering materials with biological tissues such as the cardiac, kidney, liver, intestine, cartilage, and brain. This soft engineering material mechanical property database is created for widely applied agarose hydrogels based on big-data screening and experiments conducted using ultra-low-concentration (0.01-0.5 wt %) hydrogels. Based on that, an experimental and analysis protocol is established for evaluating the elastic modulus of ultra-soft engineering materials. Overall, we built a mechanical bridge connecting soft matter and tissue engineering by fine-tuning the agarose hydrogel concentration. Meanwhile, a soft matter scale (degree of softness) is established to enable the manufacturing of implantable bio-scaffolds for tissue engineering.


Assuntos
Cartilagem , Engenharia Tecidual , Engenharia Tecidual/métodos , Sefarose , Hidrogéis , Módulo de Elasticidade , Alicerces Teciduais
7.
Front Bioeng Biotechnol ; 11: 1177688, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251575

RESUMO

Introduction: Three dimensional engineered cardiac tissues (3D ECTs) have become indispensable as in vitro models to assess drug cardiotoxicity, a leading cause of failure in pharmaceutical development. A current bottleneck is the relatively low throughput of assays that measure spontaneous contractile forces exerted by millimeter-scale ECTs typically recorded through precise optical measurement of deflection of the polymer scaffolds that support them. The required resolution and speed limit the field of view to at most a few ECTs at a time using conventional imaging. Methods: To balance the inherent tradeoff among imaging resolution, field of view and speed, an innovative mosaic imaging system was designed, built, and validated to sense contractile force of 3D ECTs seeded on a 96-well plate. Results: The system performance was validated through real-time, parallel contractile force monitoring for up to 3 weeks. Pilot drug testing was conducted using isoproterenol. Discussion: The described tool increases contractile force sensing throughput to 96 samples per measurement; significantly reduces cost, time and labor needed for preclinical cardiotoxicity assay using 3D ECT. More broadly, our mosaicking approach is a general way to scale up image-based screening in multi-well formats.

8.
IEEE Trans Biomed Eng ; 70(7): 2237-2245, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37021994

RESUMO

Three-dimensional engineered heart tissues (EHTs) derived from human induced pluripotent stem cells (iPSCs) have become an important resource for both drug toxicity screening and research on heart disease. A key metric of EHT phenotype is the contractile (twitch) force with which the tissue spontaneously beats. It is well-known that cardiac muscle contractility - its ability to do mechanical work - depends on tissue prestrain (preload) and external resistance (afterload). OBJECTIVES: Here, we demonstrate a technique to control afterload while monitoring contractile force exerted by EHTs. METHODS: We developed an apparatus that can regulate EHT boundary conditions using real-time feedback control. The system is comprised of a pair of piezoelectric actuators that can strain the scaffold and a microscope that can measure EHT force and length. Closed loop control allows dynamic regulation of effective EHT boundary stiffness. RESULTS: When controlled to switch instantaneously from auxotonic to isometric boundary conditions, EHT twitch force immediately doubled. Changes in EHT twitch force as a function of effective boundary stiffness were characterized and compared to twitch force in auxotonic conditions. CONCLUSION: EHT contractility can be regulated dynamically through feedback control of effective boundary stiffness. SIGNIFICANCE: The capacity to alter the mechanical boundary conditions of an engineered tissue dynamically offers a new way to probe tissue mechanics. This could be used to mimic afterload changes that occur naturally in disease, or to improve mechanical techniques for EHT maturation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Humanos , Miocárdio , Contração Miocárdica/fisiologia , Engenharia Tecidual/métodos
9.
ACS Appl Bio Mater ; 6(2): 908-918, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36753748

RESUMO

This study investigates the nanoindentation technique to elucidate the quasi-static and dynamic stress response at the wounded and sutured tissue interface. In vitro modeling and wound healing analysis enable an understanding of sutured tissue interface integrity, modulus, and stability using an artificial abdominal wall model. Sutured tissues with simple interrupted suturing (SIS) demonstrated a 35-40% higher modulus than simple continuous suturing (SCS). High-density suturing with a suture space of 2.5 mm exhibited a 2-fold higher modulus than low-density suturing with a suture space of 5 mm. The elastic modulus of the sutured pad immersed in deionized water was ∼70-95% of the dry condition. The dynamic stress data indicate that long-term body motions-triggered stress instability at the wound interface was affected by suturing style and density. The pivotal factors determining wound healing are quasi-static and dynamic modulus at the sutured interface, which is intimately associated with patient pain, wound complications, healing speed, and blood flow. The proposed method and data are an original approach to addressing wound healing, contributing to patient well-being and identifying, interpreting, and breaking the drawn-out debates in the suturing field.


Assuntos
Técnicas de Sutura , Cicatrização , Humanos , Suturas
10.
Nanoscale ; 15(7): 3438-3448, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722923

RESUMO

Recently, progress in electrochromic (EC) devices has been made in optimizing electrode and device configurations and performance. However, the ion insertion/de-insertion induced charge transfer (CT) nanomechanical effect has remained unexplored, i.e., repetitive electrode size changes at the nanoscale and stress/strain generated during electrochemical cycling, which is the focus of this work due to its intimate correlation with the elastic and plastic deformation at the interface. Considering the intervalence electrons, excellent electrochemical kinetics, and dramatic color changes, tungsten oxide (WO3) and nickel oxide (NiO) films are configured as the EC cathode and anode materials, respectively, within a full device. Upon extended cycles (>10 000), the void generation and delamination that occurred at the interface account for performance decay. Encouraged by the findings, nanoindentation mechanical tests and electrical kelvin probe force microscopy were employed to investigate the CT induced effects at the interface. There is a dramatic increase of up to 45% in the elastic Young's modulus in colored/charged WO3 at ∼40 mC cm-2. The correlation between CT and synergistic mechanical effect is interpreted by the Lippman equation. Interestingly, despite the charged state (colored; lithiated) with a relatively flat morphology bringing an ∼3.4 times higher electrostatic surface potential, the electrical work function unexpectedly decreases, arising from the dominant effect of the dipole layer potential over the chemical potential. The interatomic cohesive energy and equilibrium distance increase bury the seeds for mechanical deformation in the long run. This work provides fundamental insights into electro-chemo mechanics and interdisciplinary concerted interfacial effects at the nano/atomic level. The dependence of surface potential, stress, work function, and cohesive energy on electrochemical kinetics has been interpreted.

11.
ACS Biomater Sci Eng ; 9(3): 1644-1655, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36765460

RESUMO

Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) show immature features, but these are improved by integration into 3D cardiac constructs. In addition, it has been demonstrated that physical manipulations such as electrical stimulation (ES) are highly effective in improving the maturation of human-engineered cardiac tissue (hECT) derived from hiPSC-CMs. Here, we continuously applied an ES in capacitive coupling configuration, which is below the pacing threshold, to millimeter-sized hECTs for 1-2 weeks. Meanwhile, the structural and functional developments of the hECTs were monitored and measured using an array of assays. Of particular note, a nanoscale imaging technique, scanning ion conductance microscopy (SICM), has been used to directly image membrane remodeling of CMs at different locations on the tissue surface. Periodic crest/valley patterns with a distance close to the sarcomere length appeared on the membrane of CMs near the edge of the tissue after ES, suggesting the enhanced transverse tubulation network. The SICM observation is also supported by the fluorescence images of the transverse tubulation network and α-actinin. Correspondingly, essential cardiac functions such as calcium handling and contraction force generation were improved. Our study provides evidence that chronic subthreshold ES can still improve the structural and functional developments of hECTs.


Assuntos
Células-Tronco Pluripotentes Induzidas , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Miócitos Cardíacos/fisiologia , Cálcio/farmacologia , Estimulação Elétrica
12.
ACS Appl Mater Interfaces ; 14(38): 42876-42886, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36107749

RESUMO

Nanometer- and submicrometer-sized fiber have been used as scaffolds for tissue engineering, because of their fundamental load-bearing properties in synergy with mechano-transduction. This study investigates a single biodegradable poly(lactic-co-glycolic acid) (PLGA) fiber's load-displacement behavior utilizing the nanoindentation technique coupled with a high-resolution in situ imaging system. It is demonstrated that a maximum force of ∼3 µN in the radial direction and displacement of at least 150% of fiber diameter should be applied to acquire the fiber's macroscopic mechanical properties for tissue engineering. The adhesion behavior of a single fiber is captured using a high-resolution camera. The digital image correlation (DIC) technique is adopted to quantify the adhesion force (∼25 µN) between the fiber and the tip. Adhesion force has also been quantified for the fiber after immersing in phosphate-buffered saline (PBS) to mimic the bioenvironment. A 4-fold increase in adhesion force after PBS treatment was observed due to water penetration and hydrolysis on the fiber's surface. A high similarity between mechanical properties of a single fiber and native tissues (elastic modulus of 10-25 kPa) and superior adhesion force (25-107.25 µN) was observed, which is excellent for promoting cell-matrix communication. Overall, this study examines the mechanics of a single fiber using innovative indentation and imaging processing techniques, disclosing its profound and striking roles in tissue engineering.


Assuntos
Ácido Poliglicólico , Engenharia Tecidual , Glicóis , Humanos , Ácido Láctico , Fosfatos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Aderências Teciduais , Alicerces Teciduais , Água
13.
J Biomech ; 138: 111129, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35576632

RESUMO

Myocardial infarction continues to be a leading cause of mortality and morbidity globally. A major challenge post-myocardial infarction is scar tissue growth, which eventually can lead to heart failure. Cardiovascular regenerative strategies to minimize scar tissue growth and promote cardiac tissue formation are currently being actively pursued via the development of cardiac patches. However, the patch must have viscoelastic properties that mimic healthy cardiac tissues to facilitate proper cardiac patch-to-cell communications. To this end, we investigated the tissue microstructure and the stress relaxation properties of the porcine left ventricle (LV) along its long and short axes using a nanoindentation technique. We found significantly higher collagen density along the long axis than the short axis (p < 0.05). We then identified a much more rapid stress relaxation along the porcine LV's short axis compared to its long axis during the diastolic filling timeframe. Therefore, these findings show that concomitant LV pressure and volume increases from blood filling during diastole are directional dependent, with its short axis responsible for increase in LV volume and the long axis responsible for increase in LV pressure. These directional-dependent stress relaxation properties are essential in the design of structurally, bio-mimetic cardiac patches to support cardiac function and regeneration.


Assuntos
Ventrículos do Coração , Infarto do Miocárdio , Animais , Cicatriz , Diástole , Volume Sistólico , Suínos , Função Ventricular Esquerda
14.
Oxid Med Cell Longev ; 2022: 1619651, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528512

RESUMO

Sirtuin 6 (SIRT6) is an NAD+-dependent deacetylase belonging to the sirtuin family. It has been shown to participate in wound healing and some inflammation-related disorders. However, the effect of MDL-800, a highly efficient and selective SIRT6 activator, on wound healing and inflammation has not been reported. Therefore, this study investigated whether MDL-800 confers anti-inflammatory effects and promotes wound healing and uncovered the molecular mechanisms involved. This was achieved using mouse models of full-thickness wounds. Results showed that MDL-800 significantly downregulated inflammation by attenuating the release of inflammatory mediators and improved collagen deposition and neovascularization of wounds, thereby accelerating cutaneous wound healing. Furthermore, MDL-800 significantly downregulated expression levels of TNF-α and IL-6 in the dorsal skin tissue of mice via the NF-κB pathway. These results demonstrated that MDL-800 exerted anti-inflammatory and prohealing effects, indicating that the SIRT6/NF-κB/IκB signaling pathway may play an important role in wound healing.


Assuntos
NF-kappa B , Sirtuínas , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Benzoatos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , NF-kappa B/metabolismo , Neovascularização Patológica , Sirtuínas/metabolismo , Compostos de Enxofre , Cicatrização
15.
Med Sci Monit ; 28: e934424, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35184130

RESUMO

BACKGROUND The incidence of breast cancer is increasing annually. Obesity and metabolism are considered risk factors for breast cancer. Discovery of obesity- and metabolism-related breast cancer prognostic genes is imminent. MATERIAL AND METHODS We screened metabolism-related genes (MRG) from KEGG and downloaded the obese female dataset GSE151839 from GEO, which screened differentially-expressed genes (DEGs), seen as female obesity-related genes. The intersection of MRGs and DEGs was obesity-related metabolic genes (OMGs), verified by enrichment analysis. After downloading breast cancer data from TCGA, univariate Cox regression and log-rank P analyses were used to screen hub OMGs related to breast cancer prognosis. ROC curve and Kaplan-Meier (KM) plotter, GEPIA, and GENT2 databases were used to verify the hub OMGs at the RNA level. CPTAC and HLA databases were used to verify the hub OMGs at the protein level. RESULTS We screened 33 OMGs. The results of univariate Cox regression and log-rank P analysis showed 3 of 33 OMGs (ABCA1, LPIN1, HSD17B8) were associated with the prognosis of breast cancer patients. After verification with ROC, KM-plotter, and GEPIA, only HSD17B8 was related to breast cancer prognosis (overall/disease-free survival). Results of GENT2 showed the RNA expression of HSD17B8 in breast cancer subtypes with poor prognosis is significantly lower than that with good prognosis. Results of CPTAC and HLA databases showed that the protein expression level of HSD17B8 in breast cancer tissues was significantly lower than that in adjacent normal tissues. CONCLUSIONS HSD17B8 is a protective gene against breast cancer. The higher the expression of HSD17B8, the better the prognosis of breast cancer patients.


Assuntos
Neoplasias da Mama/genética , Biologia Computacional/métodos , Regulação Neoplásica da Expressão Gênica , Obesidade/genética , Oxirredutases/genética , Mapas de Interação de Proteínas/genética , Proteínas/genética , Transcriptoma/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/complicações , Neoplasias da Mama/metabolismo , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica/métodos , Genes MHC Classe I , Humanos , Obesidade/complicações , Obesidade/metabolismo , Oxirredutases/biossíntese , Prognóstico , Proteômica , Curva ROC
16.
Comput Intell Neurosci ; 2022: 9152605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36619816

RESUMO

The introduction of digital technology in the healthcare industry is marked by ongoing difficulties with implementation and use. Slow progress has been made in unifying different healthcare systems, and much of the globe still lacks a fully integrated healthcare system. As a result, it is critical and advantageous for healthcare providers to comprehend the fundamental ideas of AI in order to design and deliver their own AI-powered technology. AI is commonly defined as the capacity of machines to mimic human cognitive functions. It can tackle jobs with equivalent or superior performance to humans by combining computer science, algorithms, machine learning, and data science. The healthcare system is a dynamic and evolving environment, and medical experts are constantly confronted with new issues, shifting duties, and frequent interruptions. Because of this variation, illness diagnosis frequently becomes a secondary concern for healthcare professionals. Furthermore, clinical interpretation of medical information is a cognitively demanding endeavor. This applies not just to seasoned experts, but also to individuals with varying or limited skills, such as young assistant doctors. In this paper, we proposed the comparative analysis of various state-of-the-art methods of deep learning for medical imaging diagnosis and evaluated various important characteristics. The methodology is to evaluate various important factors such as interpretability, visualization, semantic data, and quantification of logical relationships in medical data. Furthermore, the glaucoma diagnosis system is discussed in detail via qualitative and quantitative approaches. Finally, the applications and future prospects were also discussed.


Assuntos
Algoritmos , Aprendizado de Máquina , Humanos
17.
Nanomedicine ; 29: 102262, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32623017

RESUMO

Tenacious sputum poses a critical diffusion barrier for aerosol antibiotics used to treat cystic fibrosis (CF) lung infection. We conducted a proof-of-concept study using dense poly(ethylene glycol) coated polystyrene nanoparticles (PS-PEG NPs) as model muco-inert particles (MIPs) formulated as a powder using an excipient enhanced growth (EEG) strategy, aiming to minimize extrathoracic airway loss, maximize deposition in the airway and further overcome the sputum barrier in the CF lungs. The EEG aerosol formulation containing PS-PEG MIPs was prepared by spray drying and produced discrete spherical particles with geometric diameter of approximately 2 µm; and >80% of the powder dose was delivered from a new small-animal dry powder inhaler (DPI). The MIPs released from the EEG aerosol had human airway mucus and CF sputum diffusion properties comparable to the suspension formulation. These properties make this formulation a promising pulmonary drug delivery system for CF lung infections.


Assuntos
Fibrose Cística/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Pneumopatias/tratamento farmacológico , Pulmão/efeitos dos fármacos , Nanopartículas/química , Administração por Inalação , Fibrose Cística/patologia , Inaladores de Pó Seco/métodos , Excipientes/química , Humanos , Pulmão/crescimento & desenvolvimento , Pneumopatias/patologia , Muco/efeitos dos fármacos , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Poliestirenos/química , Poliestirenos/farmacologia
18.
J Recept Signal Transduct Res ; 40(2): 173-180, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32024401

RESUMO

Breast cancer (BC) is one of the most common malignancies worldwide. Punicalagin (PN), which is a type of polyphenol, has been reported to act as a tumor suppressor. This study aimed to investigate the effects of PN on cellular process in BC and its molecular mechanism. The effects of various doses of PN on cell viability, migration, and invasion capacities of MCF-7 and MDA-MB-231 cells were detected by CCK-8, wound-healing, and Transwell assays. Golgi phosphoprotein 3 (GOLPH3) was then transfected into the cells with or without PN treatment, and GPLPH3 expression level was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, and expressions of epithelial-mesenchymal transition (EMT)-related protein matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), E-Cadherin, and N-Cadherin were measured by Western blot. High dose of PN treatment (50 µM or higher) significantly inhibited viability, migration, and invasion of MCF-7 and MDA-MB-231 cells, while overexpressed GOLPH3 promoted cell viability, migration, and invasion, and partially reversed the effects of PN treatment on the BC cells. PN inhibited the expressions of GOLPH3, MMP-2, MMP-9, and N-Cadherin, and promoted E-Cadherin expression, while overexpression of GOLPH3 partly reversed above effects attributing to PN. Thus, PN suppresses cell viability and metastasis via regulating GOLPH3 in BC, which provides a possible therapeutic direction to the treatment of BC.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Taninos Hidrolisáveis/farmacologia , Proteínas de Membrana/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Caderinas/genética , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia
19.
ACS Appl Bio Mater ; 2(12): 5916-5929, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-35021513

RESUMO

Drug (vitamin B2, riboflavin, VB2)/nanoparticle (TiO2, coated on drug surface) loaded poly(vinyl alcohol) (PVA) nanofiber webs were successfully produced by the electrospinning process. The characteristics of nanofiber structure, chemical composition, mechanical properties, and drug-release properties were investigated. The morphology and diameter of nanofibers were analyzed by atomic force microscopy and scanning electron microscopy. The chemical composition and mechanical properties of nanofiber webs were examined by Fourier transform infrared spectroscopy and Instron tensile tester. The drug-release properties of nanofiber webs were studied by liquid chromatography-mass spectrometry (LC-MS/MS). The influences of TiO2:VB2 ratios (0, 18:1, 9:1, 4.5:1, 2.25:1, and 1:1) and releasing time on release behavior of PVA/VB2/TiO2 nanofiber webs were also investigated, with the corresponding virgin PVA nanofibers and LC-MS grade water as control. Among all of the tested samples, PVA/VB2/TiO2 nanofiber webs with TiO2:VB2 ratios of 18:1 and 9:1 exhibited a steady release rate with 60% of VB2 released around 168 h and all VB2 released around 10 days. In addition, by coating VB2 with TiO2, the burst release was effectively prevented due to three mechanisms: surface modification, polymer morphology, and coated surface. The results in this study indicate drug-loaded and nanoparticle-coated hydrophilic nanofiber webs are useful candidates for steady drug release in the drug delivery application field.

20.
Am J Transl Res ; 8(7): 3106-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27508031

RESUMO

MicroRNAs (miRNAs), small non-coding RNAs, regulate fundamental cellular and developmental processes such as cell growth, apoptosis, migration, and invasion. In our present study, we investigated the inhibitory role of miR-145 on breast cancer cell migration as well as its underlying mechanism. Wound healing assay and transwell migration assay showed that ectopic expression of miR-145 significantly inhibited breast cancer cell migration. Bioinformatics analysis revealed that FSCN-1 was a putative target of miR-145. The expression of FSCN-1 varied among four different breast cancer cells, and inversely correlated with miR-145 levels. Moreover, miR-145 mimic transfection enhanced the expression of FSCN-1 in Bcap-37 and HCC-1937 cells. We also found that siRNA- mediated down-regulation of FSCN-1 inhibited cell motility in breast cancer cells. In addition, we found that up-regulation of miR-145 blocked EMT and decreased the expression of MMP-2/9 in breast cancer cells. These results reveal a new link between miR-145, FSCN-1 and EMT in the regulation of breast cancer migration.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...