Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 205
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Small ; 19(9): e2205519, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36642804

RESUMEN

Exosomes, nano-sized extracellular vesicles (EVs) secreted from cells, carry various cargo molecules reflecting their cells of origin. As EV content, structure, and size are highly heterogeneous, their classification via cargo molecules by determining their origin is challenging. Here, a method is presented combining surface-enhanced Raman spectroscopy (SERS) with machine learning algorithms to employ the classification of EVs derived from five different cell lines to reveal their cellular origins. Using an artificial neural network algorithm, it is shown that the label-free Raman spectroscopy method's prediction ratio correlates with the ratio of HT-1080 exosomes in the mixture. This machine learning-assisted SERS method enables a new direction through label-free investigation of EV preparations by differentiating cancer cell-derived exosomes from those of healthy. This approach will potentially open up new avenues of research for early detection and monitoring of various diseases, including cancer.


Asunto(s)
Exosomas , Vesículas Extracelulares , Neoplasias , Humanos , Exosomas/metabolismo , Espectrometría Raman/métodos , Vesículas Extracelulares/metabolismo , Neoplasias/diagnóstico , Neoplasias/metabolismo , Línea Celular
2.
Am J Respir Crit Care Med ; 206(8): 1019-1034, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35696338

RESUMEN

Rationale: The role of neutrophils and their extracellular vesicles (EVs) in the pathogenesis of pulmonary arterial hypertension is unclear. Objectives: To relate functional abnormalities in pulmonary arterial hypertension neutrophils and their EVs to mechanisms uncovered by proteomic and transcriptomic profiling. Methods: Production of elastase, release of extracellular traps, adhesion, and migration were assessed in neutrophils from patients with pulmonary arterial hypertension and control subjects. Proteomic analyses were applied to explain functional perturbations, and transcriptomic data were used to find underlying mechanisms. CD66b-specific neutrophil EVs were isolated from plasma of patients with pulmonary arterial hypertension, and we determined whether they produce pulmonary hypertension in mice. Measurements and Main Results: Neutrophils from patients with pulmonary arterial hypertension produce and release increased neutrophil elastase, associated with enhanced extracellular traps. They exhibit reduced migration and increased adhesion attributed to elevated ß1-integrin and vinculin identified by proteomic analysis and previously linked to an antiviral response. This was substantiated by a transcriptomic IFN signature that we related to an increase in human endogenous retrovirus K envelope protein. Transfection of human endogenous retrovirus K envelope in a neutrophil cell line (HL-60) increases neutrophil elastase and IFN genes, whereas vinculin is increased by human endogenous retrovirus K deoxyuridine triphosphate diphosphatase that is elevated in patient plasma. Neutrophil EVs from patient plasma contain increased neutrophil elastase and human endogenous retrovirus K envelope and induce pulmonary hypertension in mice, mitigated by elafin, an elastase inhibitor. Conclusions: Elevated human endogenous retroviral elements and elastase link a neutrophil innate immune response to pulmonary arterial hypertension.


Asunto(s)
Retrovirus Endógenos , Hipertensión Pulmonar , Hipertensión Arterial Pulmonar , Animales , Antivirales , Elafina/genética , Elafina/metabolismo , Elafina/farmacología , Retrovirus Endógenos/metabolismo , Hipertensión Pulmonar Primaria Familiar/genética , Humanos , Hipertensión Pulmonar/genética , Integrinas/genética , Integrinas/metabolismo , Elastasa de Leucocito/metabolismo , Ratones , Neutrófilos/metabolismo , Proteómica , Vinculina/genética , Vinculina/metabolismo
3.
Angew Chem Int Ed Engl ; 62(16): e202217932, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-36622783

RESUMEN

Exosomal microRNAs (miRNAs) have considerable potential as pivotal biomarkers to monitor cancer development, dis-ease progression, treatment effects and prognosis. Here, we report an efficient target recycling amplification process (TRAP) for the digital detection of miRNAs using photonic resonator absorption microscopy. We achieve multiplex digital detection with sub-attomolar sensitivity in 20 minutes, robust selectivity for single nucleotide variants, and a broad dynamic range from 1 aM to 1 pM. Compared with traditional qRT-PCR, TRAP showed similar accuracy in profiling exosomal miRNAs derived from cancer cells, but also exhibited at least 31-fold and 61-fold enhancement in the limits of miRNA-375 and miRNA-21 detection, respectively. The TRAP approach is ideal for exosomal or circulating miRNA biomarker quantification, where the miRNAs are present in low concentrations or sample volume, with potentials for frequent, low-cost, and minimally invasive point-of-care testing.


Asunto(s)
Técnicas Biosensibles , Exosomas , MicroARNs , MicroARNs/análisis , Microscopía , Técnicas de Amplificación de Ácido Nucleico , Fotones , Pronóstico , Exosomas/química
4.
Circulation ; 139(14): 1710-1724, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30586764

RESUMEN

BACKGROUND: Pulmonary arterial hypertension (PAH) is a life-threatening disorder of the pulmonary circulation associated with loss and impaired regeneration of microvessels. Reduced pericyte coverage of pulmonary microvessels is a pathological feature of PAH and is caused partly by the inability of pericytes to respond to signaling cues from neighboring pulmonary microvascular endothelial cells (PMVECs). We have shown that activation of the Wnt/planar cell polarity pathway is required for pericyte recruitment, but whether production and release of specific Wnt ligands by PMVECs are responsible for Wnt/planar cell polarity activation in pericytes is unknown. METHODS: Isolation of pericytes and PMVECs from healthy donor and PAH lungs was carried out with 3G5 or CD31 antibody-conjugated magnetic beads. Wnt expression profile of PMVECs was documented via quantitative polymerase chain reaction with a Wnt primer library. Exosome purification from PMVEC media was carried out with the ExoTIC device. Hemodynamic profile, right ventricular function, and pulmonary vascular morphometry were obtained in a conditional endothelium-specific Wnt5a knockout ( Wnt5aECKO) mouse model under normoxia, chronic hypoxia, and hypoxia recovery. RESULTS: Quantification of Wnt ligand expression in healthy PMVECs cocultured with pericytes demonstrated a 35-fold increase in Wnt5a, a known Wnt/planar cell polarity ligand. This Wnt5a spike was not seen in PAH PMVECs, which correlated with an inability to recruit pericytes in Matrigel coculture assays. Exosomes purified from media demonstrated an increase in Wnt5a content when healthy PMVECs were cocultured with pericytes, a finding that was not observed in exosomes of PAH PMVECs. Furthermore, the addition of either recombinant Wnt5a or purified healthy PMVEC exosomes increased pericyte recruitment to PAH PMVECs in coculture studies. Although no differences were noted in normoxia and chronic hypoxia, Wnt5aECKO mice demonstrated persistent pulmonary hypertension and right ventricular failure 4 weeks after recovery from chronic hypoxia, which correlated with significant reduction, muscularization, and decreased pericyte coverage of microvessels. CONCLUSIONS: We identify Wnt5a as a key mediator for the establishment of pulmonary endothelium-pericyte interactions, and its loss could contribute to PAH by reducing the viability of newly formed vessels. We speculate that therapies that mimic or restore Wnt5a production could help prevent loss of small vessels in PAH.


Asunto(s)
Movimiento Celular , Células Endoteliales/metabolismo , Pericitos/metabolismo , Hipertensión Arterial Pulmonar/metabolismo , Arteria Pulmonar/metabolismo , Proteína Wnt-5a/deficiencia , Adolescente , Adulto , Animales , Estudios de Casos y Controles , Hipoxia de la Célula , Polaridad Celular , Células Cultivadas , Niño , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Células Endoteliales/patología , Exosomas/metabolismo , Exosomas/patología , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Neovascularización Patológica , Comunicación Paracrina , Pericitos/patología , Hipertensión Arterial Pulmonar/genética , Hipertensión Arterial Pulmonar/patología , Arteria Pulmonar/patología , Ratas , Vía de Señalización Wnt , Proteína Wnt-5a/genética
5.
Small ; 16(49): e2005185, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33174334

RESUMEN

Manufacturing mobile artificial micromotors with structural design factors, such as morphology nanoroughness and surface chemistry, can improve the capture efficiency through enhancing contact interactions with their surrounding targets. Understanding the interplay of such parameters targeting high locomotion performance and high capture efficiency at the same time is of paramount importance, yet, has so far been overlooked. Here, an immunocyte-templated nano-topographical micromotor is engineered and their interactions with various targets across multiple scales, from ions to cells are investigated. The macrophage templated nanorough micromotor demonstrates significantly increased surface interactions and significantly improved and highly efficient removal of targets from complex aqueous solutions, including in plasma and diluted blood, when compared to smooth synthetic material templated micromotors with the same size and surface chemistry. These results suggest that the surface nanoroughness of the micromotors for the locomotion performance and interactions with the multiscale targets should be considered simultaneously, for they are highly interconnected in design considerations impacting applications across scales.


Asunto(s)
Iones
6.
Hum Reprod ; 33(8): 1388-1393, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30007319

RESUMEN

STUDY QUESTION: Does microfluidic sorting improve the selection of sperm with lower DNA fragmentation over standard density-gradient centrifugation? SUMMARY ANSWER: Microfluidic sorting of unprocessed semen allows for the selection of clinically usable, highly motile sperm with nearly undetectable levels of DNA fragmentation. WHAT IS KNOWN ALREADY: Microfluidic devices have been explored to sort motile and morphologically normal sperm from a raw sample without centrifugation; however, it is uncertain whether DNA damage is reduced in this process. STUDY DESIGN, SIZE, DURATION: This is a blinded, controlled laboratory study of differences in standard semen analysis parameters and the DNA fragmentation index (DFI) in split samples from infertile men (n = 70) that were discarded after routine semen analysis at an academic medical center. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm concentration, progressive motility and forward progression were assessed by microscopic examination. For each sample, the unprocessed semen was tested for DNA fragmentation and split for processing by density-gradient centrifugation with swim-up or sorting by a microfluidic chip. DNA fragmentation was assessed in unprocessed and processed samples by sperm chromatin dispersion assay. The DFI was calculated, from up to 300 cells per slide, as the number of cells with fragmented DNA divided by the number of cells counted per slide. MAIN RESULTS AND THE ROLE OF CHANCE: The median DFI in unprocessed samples was 21% (interquartile range (IQR): 14-30). In paired analyses of all samples, those processed by the microfluidic chip demonstrated significantly decreased DFI compared to those processed by density-gradient centrifugation (P = 0.0029) and unprocessed samples (P < 0.0001). The median DFI for chip specimens was 0% (IQR: 0-2.4) while those processed by density-gradient centrifugation had a median DFI of 6% (IQR: 2-11). Unprocessed samples in the highest DFI quartile (DFI range: 31-40%) had a median DFI of 15% (IQR: 11-19%) after density-gradient centrifugation and DFI of 0% (IQR: 0-1.9%) after processing with the microfluidic chip (P = 0.02). LIMITATIONS, REASONS FOR CAUTION: While a high DFI has been associated with poor outcomes with IVF/ICSI, there are limited data illustrating improvements in clinical outcomes with a reduction in DFI. As this study utilized discarded, non-clinical samples, clinical outcomes data are not available. WIDER IMPLICATIONS OF THE FINDINGS: While microfluidic sorting of unprocessed semen allowed for the selection of clinically usable, highly motile sperm with nearly undetectable levels of DNA fragmentation, standard processing by density-gradient centrifugation with swim-up did not increase DNA fragmentation in an infertile population. The proposed microfluidic technology offers a flow-free approach to sort sperm, requiring no peripheral equipment or filtration step, while minimizing hands-on time. STUDY FUNDING/COMPETING INTEREST(S): No external funding to declare. Utkan Demirci, PhD is the Co-founder and Scientific Advisor for DxNow Inc., LevitasBio Inc. and Koek Biotech. Mitchell Rosen, MD is a member of the Clinical Advisory Board for DxNow Inc.


Asunto(s)
Separación Celular/métodos , Centrifugación por Gradiente de Densidad , Daño del ADN , Infertilidad Masculina/diagnóstico , Técnicas Analíticas Microfluídicas , Análisis de Semen/métodos , Espermatozoides/patología , Separación Celular/instrumentación , Humanos , Infertilidad Masculina/genética , Infertilidad Masculina/patología , Dispositivos Laboratorio en un Chip , Masculino , Técnicas Analíticas Microfluídicas/instrumentación , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Análisis de Semen/instrumentación , Recuento de Espermatozoides , Motilidad Espermática
7.
Proc Natl Acad Sci U S A ; 112(28): E3661-8, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26124131

RESUMEN

Several cellular events cause permanent or transient changes in inherent magnetic and density properties of cells. Characterizing these changes in cell populations is crucial to understand cellular heterogeneity in cancer, immune response, infectious diseases, drug resistance, and evolution. Although magnetic levitation has previously been used for macroscale objects, its use in life sciences has been hindered by the inability to levitate microscale objects and by the toxicity of metal salts previously applied for levitation. Here, we use magnetic levitation principles for biological characterization and monitoring of cells and cellular events. We demonstrate that each cell type (i.e., cancer, blood, bacteria, and yeast) has a characteristic levitation profile, which we distinguish at an unprecedented resolution of 1 × 10(-4) g ⋅ mL(-1). We have identified unique differences in levitation and density blueprints between breast, esophageal, colorectal, and nonsmall cell lung cancer cell lines, as well as heterogeneity within these seemingly homogenous cell populations. Furthermore, we demonstrate that changes in cellular density and levitation profiles can be monitored in real time at single-cell resolution, allowing quantification of heterogeneous temporal responses of each cell to environmental stressors. These data establish density as a powerful biomarker for investigating living systems and their responses. Thereby, our method enables rapid, density-based imaging and profiling of single cells with intriguing applications, such as label-free identification and monitoring of heterogeneous biological changes under various physiological conditions, including antibiotic or cancer treatment in personalized medicine.


Asunto(s)
Magnetismo , Análisis de la Célula Individual , Antiinfecciosos/farmacología , Bacterias/citología , Bacterias/efectos de los fármacos , Línea Celular Tumoral , Medios de Cultivo , Eritrocitos/citología , Humanos , Leucocitos/citología , Modelos Teóricos , Levaduras/citología , Levaduras/efectos de los fármacos
8.
Proc Natl Acad Sci U S A ; 112(32): E4354-63, 2015 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-26195743

RESUMEN

Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients' homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE(2)RD), which addresses all these impediments on a single platform. The NE(2)RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE(2)RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE(2)RD's broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients' homes.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas y Procedimientos Diagnósticos/instrumentación , Electricidad , Nanoestructuras/química , Línea Celular Tumoral , Coinfección/diagnóstico , Ambiente , Ensayo de Inmunoadsorción Enzimática , Diseño de Equipo , Humanos , Concentración de Iones de Hidrógeno , Límite de Detección , Microfluídica , Concentración Osmolar , Reproducibilidad de los Resultados , Temperatura
9.
IEEE Sens J ; 18(4): 1464-1473, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29881332

RESUMEN

We report on the implementation of an automated platform for detecting the presence of an antibody biomarker for human papillomavirus-associated oropharyngeal cancer from a single droplet of serum, in which a nanostructured photonic crystal surface is used to amplify the output of a fluorescence-linked immunosorbent assay. The platform is comprised of a microfluidic cartridge with integrated photonic crystal chips that interfaces with an assay instrument that automates the introduction of reagents, wash steps, and surface drying. Upon assay completion, the cartridge interfaces with a custom laser-scanning instrument that couples light into the photonic crystal at the optimal resonance condition for fluorescence enhancement. The instrument is used to measure the fluorescence intensity values of microarray spots corresponding to the biomarkers of interest, in addition to several experimental controls that verify correct functioning of the assay protocol. In this work, we report both dose-response characterization of the system using anti-E7 antibody introduced at known concentrations into serum and characterization of a set of clinical samples from which results were compared with a conventional enzyme-linked immunosorbent assay (ELISA) performed in microplate format. The demonstrated capability represents a simple, rapid, automated, and high-sensitivity method for multiplexed detection of protein biomarkers from a low-volume test sample.

10.
Chem Soc Rev ; 46(2): 366-388, 2017 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-27841420

RESUMEN

Biosensors are extensively employed for diagnosing a broad array of diseases and disorders in clinical settings worldwide. The implementation of biosensors at the point-of-care (POC), such as at primary clinics or the bedside, faces impediments because they may require highly trained personnel, have long assay times, large sizes, and high instrumental cost. Thus, there exists a need to develop inexpensive, reliable, user-friendly, and compact biosensing systems at the POC. Biosensors incorporated with photonic crystal (PC) structures hold promise to address many of the aforementioned challenges facing the development of new POC diagnostics. Currently, PC-based biosensors have been employed for detecting a variety of biotargets, such as cells, pathogens, proteins, antibodies, and nucleic acids, with high efficiency and selectivity. In this review, we provide a broad overview of PCs by explaining their structures, fabrication techniques, and sensing principles. Furthermore, we discuss recent applications of PC-based biosensors incorporated with emerging technologies, including telemedicine, flexible and wearable sensing, smart materials and metamaterials. Finally, we discuss current challenges associated with existing biosensors, and provide an outlook for PC-based biosensors and their promise at the POC.


Asunto(s)
Técnicas Biosensibles , Fotones , Sistemas de Atención de Punto , Humanos , Nanoestructuras/química
11.
Annu Rev Med ; 66: 387-405, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25423597

RESUMEN

The global HIV/AIDS pandemic has resulted in 39 million deaths to date, and there are currently more than 35 million people living with HIV worldwide. Prevention, screening, and treatment strategies have led to major progress in addressing this disease globally. Diagnostics is critical for HIV prevention, screening and disease staging, and monitoring antiretroviral therapy (ART). Currently available diagnostic assays, which include polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and western blot (WB), are complex, expensive, and time consuming. These diagnostic technologies are ill suited for use in low- and middle-income countries, where the challenge of the HIV/AIDS pandemic is most severe. Therefore, innovative, inexpensive, disposable, and rapid diagnostic platform technologies are urgently needed. In this review, we discuss challenges associated with HIV management in resource-constrained settings and review the state-of-the-art HIV diagnostic technologies for CD4(+) T lymphocyte count, viral load measurement, and drug resistance testing.


Asunto(s)
Recuento de Linfocito CD4 , Farmacorresistencia Viral , Infecciones por VIH/diagnóstico , Sistemas de Atención de Punto , ARN Viral/análisis , Carga Viral , Fármacos Anti-VIH/uso terapéutico , Manejo de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Proteína p24 del Núcleo del VIH/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Humanos , Técnicas Analíticas Microfluídicas , Reacción en Cadena de la Polimerasa
13.
Small ; 12(9): 1222-1229, 2016 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-26523938

RESUMEN

There is an emerging need for portable, robust, inexpensive, and easy-to-use disease diagnosis and prognosis monitoring platforms to share health information at the point-of-living, including clinical and home settings. Recent advances in digital health technologies have improved early diagnosis, drug treatment, and personalized medicine. Smartphones with high-resolution cameras and high data processing power enable intriguing biomedical applications when integrated with diagnostic devices. Further, these devices have immense potential to contribute to public health in resource-limited settings where there is a particular need for portable, rapid, label-free, easy-to-use, and affordable biomedical devices to diagnose and continuously monitor patients for precision medicine, especially those suffering from rare diseases, such as sickle cell anemia, thalassemia, and chronic fatigue syndrome. Here, a magnetic levitation-based diagnosis system is presented in which different cell types (i.e., white and red blood cells) are levitated in a magnetic gradient and separated due to their unique densities. Moreover, an easy-to-use, smartphone incorporated levitation system for cell analysis is introduced. Using our portable imaging magnetic levitation (i-LEV) system, it is shown that white and red blood cells can be identified and cell numbers can be quantified without using any labels. In addition, cells levitated in i-LEV can be distinguished at single-cell resolution, potentially enabling diagnosis and monitoring, as well as clinical and research applications.


Asunto(s)
Teléfono Celular , Eritrocitos/patología , Imagenología Tridimensional/métodos , Magnetismo , Recuento de Células Sanguíneas , Humanos , Leucocitos/patología , Análisis de la Célula Individual
14.
Proc Natl Acad Sci U S A ; 110(22): E1974-83, 2013 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-23645635

RESUMEN

Seventy-five percent of patients with epithelial ovarian cancer present with advanced-stage disease that is extensively disseminated intraperitoneally and prognosticates the poorest outcomes. Primarily metastatic within the abdominal cavity, ovarian carcinomas initially spread to adjacent organs by direct extension and then disseminate via the transcoelomic route to distant sites. Natural fluidic streams of malignant ascites triggered by physiological factors, including gravity and negative subdiaphragmatic pressure, carry metastatic cells throughout the peritoneum. We investigated the role of fluidic forces as modulators of metastatic cancer biology in a customizable microfluidic platform using 3D ovarian cancer nodules. Changes in the morphological, genetic, and protein profiles of biomarkers associated with aggressive disease were evaluated in the 3D cultures grown under controlled and continuous laminar flow. A modulation of biomarker expression and tumor morphology consistent with increased epithelial-mesenchymal transition, a critical step in metastatic progression and an indicator of aggressive disease, is observed because of hydrodynamic forces. The increase in epithelial-mesenchymal transition is driven in part by a posttranslational up-regulation of epidermal growth factor receptor (EGFR) expression and activation, which is associated with the worst prognosis in ovarian cancer. A flow-induced, transcriptionally regulated decrease in E-cadherin protein expression and a simultaneous increase in vimentin is observed, indicating increased metastatic potential. These findings demonstrate that fluidic streams induce a motile and aggressive tumor phenotype. The microfluidic platform developed here potentially provides a flow-informed framework complementary to conventional mechanism-based therapeutic strategies, with broad applicability to other lethal malignancies.


Asunto(s)
Transición Epitelial-Mesenquimal/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Técnicas Analíticas Microfluídicas/métodos , Modelos Biológicos , Neoplasias Glandulares y Epiteliales/secundario , Neoplasias Ováricas/fisiopatología , Neoplasias Peritoneales/secundario , Ascitis/fisiopatología , Biomarcadores de Tumor/metabolismo , Cadherinas/metabolismo , Técnicas de Cultivo de Célula , Receptores ErbB/metabolismo , Femenino , Humanos
15.
Mater Today (Kidlington) ; 18(10): 539-553, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28458612

RESUMEN

The natural microenvironment of tumors is composed of extracellular matrix (ECM), blood vasculature, and supporting stromal cells. The physical characteristics of ECM as well as the cellular components play a vital role in controlling cancer cell proliferation, apoptosis, metabolism, and differentiation. To mimic the tumor microenvironment outside the human body for drug testing, two-dimensional (2-D) and murine tumor models are routinely used. Although these conventional approaches are employed in preclinical studies, they still present challenges. For example, murine tumor models are expensive and difficult to adopt for routine drug screening. On the other hand, 2-D in vitro models are simple to perform, but they do not recapitulate natural tumor microenvironment, because they do not capture important three-dimensional (3-D) cell-cell, cell-matrix signaling pathways, and multi-cellular heterogeneous components of the tumor microenvironment such as stromal and immune cells. The three-dimensional (3-D) in vitro tumor models aim to closely mimic cancer microenvironments and have emerged as an alternative to routinely used methods for drug screening. Herein, we review recent advances in 3-D tumor model generation and highlight directions for future applications in drug testing.

16.
Mol Pharm ; 11(7): 2151-9, 2014 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-24495169

RESUMEN

Over the past decade, bioprinting has emerged as a promising patterning strategy to organize cells and extracellular components both in two and three dimensions (2D and 3D) to engineer functional tissue mimicking constructs. So far, tissue printing has neither been used for 3D patterning of mesenchymal stem cells (MSCs) in multiphase growth factor embedded 3D hydrogels nor been investigated phenotypically in terms of simultaneous differentiation into different cell types within the same micropatterned 3D tissue constructs. Accordingly, we demonstrated a biochemical gradient by bioprinting nanoliter droplets encapsulating human MSCs, bone morphogenetic protein 2 (BMP-2), and transforming growth factor ß1 (TGF- ß1), engineering an anisotropic biomimetic fibrocartilage microenvironment. Assessment of the model tissue construct displayed multiphasic anisotropy of the incorporated biochemical factors after patterning. Quantitative real time polymerase chain reaction (qRT-PCR) results suggested genomic expression patterns leading to simultaneous differentiation of MSC populations into osteogenic and chondrogenic phenotype within the multiphasic construct, evidenced by upregulation of osteogenesis and condrogenesis related genes during in vitro culture. Comprehensive phenotypic network and pathway analysis results, which were based on genomic expression data, indicated activation of differentiation related mechanisms, via signaling pathways, including TGF, BMP, and vascular endothelial growth factor.


Asunto(s)
Biomimética/métodos , Bioimpresión/métodos , Microambiente Celular/fisiología , Fibrocartílago/fisiología , Hidrogeles/metabolismo , Células Madre Mesenquimatosas/fisiología , Ingeniería de Tejidos/métodos , Proteína Morfogenética Ósea 2/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Células Cultivadas , Microambiente Celular/genética , Condrogénesis/genética , Condrogénesis/fisiología , Fibrocartílago/metabolismo , Expresión Génica/genética , Humanos , Células Madre Mesenquimatosas/metabolismo , Osteogénesis/genética , Osteogénesis/fisiología , Transducción de Señal/genética , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
17.
J Opt Soc Am A Opt Image Sci Vis ; 31(2): 312-21, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24562030

RESUMEN

Commercial off-the-shelf digital cameras are inexpensive and easy-to-use instruments that can be used for quantitative scientific data acquisition if images are captured in raw format and processed so that they maintain a linear relationship with scene radiance. Here we describe the image-processing steps required for consistent data acquisition with color cameras. In addition, we present a method for scene-specific color calibration that increases the accuracy of color capture when a scene contains colors that are not well represented in the gamut of a standard color-calibration target. We demonstrate applications of the proposed methodology in the fields of biomedical engineering, artwork photography, perception science, marine biology, and underwater imaging.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Fotograbar/métodos , Animales , Arte , Calibración , Color , Decapodiformes , Ecosistema , Sodio
18.
Chem Soc Rev ; 42(13): 5788-808, 2013 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-23575660

RESUMEN

Recent technological advances provide new tools to manipulate cells and biological agents in micro/nano-liter volumes. With precise control over small volumes, the cell microenvironment and other biological agents can be bioengineered; interactions between cells and external stimuli can be monitored; and the fundamental mechanisms such as cancer metastasis and stem cell differentiation can be elucidated. Technological advances based on the principles of electrical, magnetic, chemical, optical, acoustic, and mechanical forces lead to novel applications in point-of-care diagnostics, regenerative medicine, in vitro drug testing, cryopreservation, and cell isolation/purification. In this review, we first focus on the underlying mechanisms of emerging examples for cell manipulation in small volumes targeting applications such as tissue engineering. Then, we illustrate how these mechanisms impact the aforementioned biomedical applications, discuss the associated challenges, and provide perspectives for further development.


Asunto(s)
Bioingeniería/métodos , Técnicas Analíticas Microfluídicas/métodos , Modelos Biológicos , Nanomedicina/métodos , Animales , Bioimpresión , Humanos
19.
Biofabrication ; 16(2)2024 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-38306674

RESUMEN

Glandular cancers are amongst the most prevalent types of cancer, which can develop in many different organs, presenting challenges in their detection as well as high treatment variability and failure rates. For that purpose, anticancer drugs are commonly tested in cancer cell lines grown in 2D tissue culture on plastic dishesin vitro, or in animal modelsin vivo. However, 2D culture models diverge significantly from the 3D characteristics of living tissues and animal models require extensive animal use and time. Glandular cancers, such as prostate cancer-the second leading cause of male cancer death-typically exist in co-centrical architectures where a cell layer surrounds an acellular lumen. Herein, this spatial cellular position and 3D architecture, containing dual compartments with different hydrogel materials, is engineered using a simple co-axial nozzle setup, in a single step utilizing prostate as a model of glandular cancer. The resulting hydrogel soft structures support viable prostate cancer cells of different cell lines and enable over-time maturation into cancer-mimicking aggregates surrounding the acellular core. The biofabricated cancer mimicking structures are then used as a model to predict the inhibitory efficacy of the poly ADP ribose polymerase inhibitor, Talazoparib, and the antiandrogen drug, Enzalutamide, in the growth of the cancer cell layer. Our results show that the obtained hydrogel constructs can be adapted to quickly obtain 3D cancer models which combine 3D physiological architectures with high-throughput screening to detect and optimize anti-cancer drugs in prostate and potentially other glandular cancer types.


Asunto(s)
Antineoplásicos , Neoplasias de la Próstata , Humanos , Animales , Masculino , Hidrogeles/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Línea Celular
20.
Small ; 9(15): 2553-63, 2478, 2013 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-23447456

RESUMEN

Development of portable biosensors has broad applications in environmental monitoring, clinical diagnosis, public health, and homeland security. There is an unmet need for pathogen detection at the point-of-care (POC) using a fast, sensitive, inexpensive, and easy-to-use method that does not require complex infrastructure and well-trained technicians. For instance, detection of Human Immunodeficiency Virus (HIV-1) at acute infection stage has been challenging, since current antibody-based POC technologies are not effective due to low concentration of antibodies. In this study, we demonstrated for the first time a label-free electrical sensing method that can detect lysed viruses, i.e. viral nano-lysate, through impedance analysis, offering an alternative technology to the antibody-based methods such as dipsticks and Enzyme-linked Immunosorbent Assay (ELISA). The presented method is a broadly applicable platform technology that can potentially be adapted to detect multiple pathogens utilizing impedance spectroscopy for other infectious diseases including herpes, influenza, hepatitis, pox, malaria, and tuberculosis. The presented method offers a rapid and portable tool that can be used as a detection technology at the POC in resource-constrained settings, as well as hospital and primary care settings.


Asunto(s)
Técnicas Biosensibles/métodos , Electricidad , VIH-1/aislamiento & purificación , Dispositivos Laboratorio en un Chip , Nanopartículas/química , Coloración y Etiquetado , Espectroscopía Dieléctrica , Fluorescencia , Humanos , Fenómenos Magnéticos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA