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1.
Lab Chip ; 24(4): 707-718, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38230917

RESUMO

Nano-roughness has shown great potential in enhancing high-fidelity electrogenic cell interfaces, owing to its characteristic topography comparable to proteins and lipids, which influences a wide range of cellular mechanical responses. Gaining a comprehensive understanding of how cells respond to nano-roughness at the single-cell level is not only imperative for implanted devices but also essential for tissue regeneration and interaction with complex biomaterial surfaces. In this study, we quantify cell adhesion and biomechanics of single cells to nano-roughened surfaces by measuring neural cell adhesion and biomechanics via fluidic-based single-cell force spectroscopy (SCFS). For this, we introduce nanoscale topographical features on polyimide (PI) surfaces achieving roughness up to 25 nm without chemical modifications. Initial adhesion experiments show cell-specific response to nano-roughness for neuroblastoma cells (SH-SY5Y) compared to human astrocytes (NHA) around 15 and 20 nm surface roughness. In addition, our SCFS measurements revealed a remarkable 2.5-fold increase in adhesion forces (150-164 nN) for SH-SY5Y cells cultured on roughened PI (rPI) surfaces compared to smooth surfaces (60-107 nN). Our data also shows that cells can distinguish changes in nano-roughness as small 2 nm (close to the diameter of a single lipid) and show roughness dependence adhesion while favoring 15 nm. Notably, this enhanced adhesion is accompanied by increased cell elongation upon cell detachment without any significant differences in cell area spreading. The study provides valuable insights into the interplay between nano-topography and cellular responses and offers practical implications for designing biomaterial surfaces with enhanced cellular interactions.


Assuntos
Neuroblastoma , Humanos , Adesão Celular , Propriedades de Superfície , Materiais Biocompatíveis/química , Análise Espectral , Lipídeos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38083031

RESUMO

With the ever-increasing need for miniaturized and biocompatible devices for physiological recordings, high signal fidelity and ease of fabrication are key to achieve reliable data collection. This calls for the development of active recording devices such as Organic Electrochemical Transistors (OECTs) which, compared to passive electrodes, offer local amplification. In this work, we built PEDOT:PSS based OECTs using novel inkjet printing technology, achieving a transconductance of 75 mS. The device was later used to amplify arbitrary signals simulating in vivo recordings. Gate voltage offset manipulation offered a range of current peak-to-peak amplitudes. Additionally, we demonstrate a simple circuit for voltage readings, where another resistor-dependent characterization involving voltage source and drain voltage is performed. At ideal operating point and when using a 220 Ω resistor, a gain of 14.5 is achieved.Clinical Relevance- 1This work demonstrates the ability to rapidly and easily develop OECT-based technology for potential signal sensing for more accurate diagnosis of pathologies and diseases.


Assuntos
Tecnologia , Coleta de Dados , Eletrodos
3.
Artigo em Inglês | MEDLINE | ID: mdl-38083716

RESUMO

Cancer invasiveness significantly impacts cellular mechanical properties which regulate cell motility and, subsequently, cell metastatic potential. Understanding the adhesion forces and stiffness/rigidity of cancer cells can provide better insights into their mechanical adaptability related to their degree of invasiveness. Here, we used single-cell force spectroscopy in conjunction with quartz crystal microbalance-with dissipation measurements to compare the mechanical properties of mammary epithelial cancer cells with different metastatic potentials, namely MCF-7 (non-invasive) and MDA-MB-231 (aggressive and highly invasive). Our results showed that MCF-7 exhibits larger adhesion forces, stronger intercellular forces, and a considerably stiff/rigid phenotype, contrary to MDA-MB-231. The biomechanical properties obtained are associated with the malignant potential of these cells such that the forces of adhesion and viscoelasticity are inversely proportional to cell invasiveness. This study integrates a new quantitative tool with real-time measurements to provide better insights into the mechanics of cancer cells across metastatic stages.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Movimento Celular , Fenômenos Mecânicos
4.
Rev Neurosci ; 33(3): 327-345, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35170265

RESUMO

Traumatic brain injury (TBI) is a major cause of mortality and morbidity, affecting 2 million people annually in the US alone, with direct and indirect costs of $76.3 billion per year. TBI is a progressive disease with no FDA-approved drug for treating patients. Early, accurate and rapid diagnosis can have significant implications for successful triaging and intervention. Unfortunately, current clinical tests for TBI rely on CT scans and MRIs, both of which are expensive, time-consuming, and not accessible to everyone. Recent evidence of biofluid-based biomarkers being released right after a TBI incident has ignited interest in developing point-of-care (POC) platforms for early and on-site TBI diagnosis. These efforts face many challenges to accurate, sensitive, and specific diagnosis and monitoring of TBI. This review includes a deep dive into the latest advances in chemical, mechanical, electrical, and optical sensing systems that hold promise for TBI-POC diagnostic testing platforms. It also focuses on the performance of these proposed biosensors compared to biofluid-based orthodox diagnostic techniques in terms of sensitivity, specificity, and limits of detection. Finally, it examines commercialized TBI-POCs present in the market, the challenges associated with them, and the future directions and prospects of these technologies and the field.


Assuntos
Técnicas Biossensoriais , Lesões Encefálicas Traumáticas , Biomarcadores , Técnicas Biossensoriais/métodos , Lesões Encefálicas Traumáticas/diagnóstico , Humanos , Sistemas Automatizados de Assistência Junto ao Leito
5.
Acta Biomater ; 122: 186-198, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33444795

RESUMO

Glycosaminoglycans (GAG) are key elements involved in various physiological and pathological processes including cancer. Several GAG-based drugs have been developed showing significant results and potential use as cancer therapeutics. We previously reported that alginate sulfate (AlgSulf), a GAG-mimetic, reduces the proliferation of lung adenocarcinoma cells. In this study, we evaluated the preferential effect of AlgSulf on tumorigenic and nontumorigenic mammary epithelial cells in 2D, 3D, and coculture conditions. AlgSulf were synthesized with different degrees of sulfation (DSs) varying from 0 to 2.7 and used at 100 µg/mL on HMT-3522 S1 (S1) nontumorigenic mammary epithelial cells and their tumorigenic counterparts HMT-3522 T4-2 (T4-2) cells. The anti-tumor properties of AlgSulf were assessed using trypan blue and bromodeoxyuridine proliferation (BrdU) assays, immunofluorescence staining and transwell invasion assay.  Binding of insulin and epidermal growth factor (EGF) to sulfated substrates was measured using QCM-D and ELISA. In 2D, the cell growth rate of cells treated with AlgSulf was consistently lower compared to untreated controls (p<0.001) and surpassed the effect of the native GAG heparin (positive control). In 3D, AlgSulf preferentially hindered the growth rate and the invasion potential of tumorigenic T4-2 nodules while maintaining the formation of differentiated polarized nontumorigenic S1 acini. The preferential growth inhibition of tumorigenic cells by AlgSulf was confirmed in a coculture system (p<0.001). In the ELISA assay, a trend of EGF binding was detected for sulfated polysaccharides while QCM-D analysis showed negligible binding of insulin and EGF to sulfated substrates. The preferential effect mediated by the mimetic sulfated GAGs on cancer cells may in part be growth factor dependent. Our findings suggest a potential anticancer therapeutic role of AlgSulf for the development of anticancer drugs.


Assuntos
Biomimética , Neoplasias Pulmonares , Antígenos de Diferenciação , Proliferação de Células , Células Epiteliais , Glicosaminoglicanos , Humanos
6.
Cancers (Basel) ; 12(7)2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32708837

RESUMO

The potential clinical utility of circulating tumor cells (CTCs) in the diagnosis and management of cancer has drawn a lot of attention in the past 10 years. CTCs disseminate from tumors into the bloodstream and are believed to carry vital information about tumor onset, progression, and metastasis. In addition, CTCs reflect different biological aspects of the primary tumor they originate from, mainly in their genetic and protein expression. Moreover, emerging evidence indicates that CTC liquid biopsies can be extended beyond prognostication to pharmacodynamic and predictive biomarkers in cancer patient management. A key challenge in harnessing the clinical potential and utility of CTCs is enumerating and isolating these rare heterogeneous cells from a blood sample while allowing downstream CTC analysis. That being said, there have been serious doubts regarding the potential value of CTCs as clinical biomarkers for cancer due to the low number of promising outcomes in the published results. This review aims to present an overview of the current preclinical CTC detection technologies and the advantages and limitations of each sensing platform, while surveying and analyzing the published evidence of the clinical utility of CTCs.

7.
Life Sci ; 251: 117639, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32272181

RESUMO

AIMS: To reduce the dose of arsenic used against human T-cell leukemia/lymphoma and to sensitize cells to drug treatment, we combined arsenic/interferon-alpha (As/IFN-α) with thymoquinone (TQ) in HTLV-I positive (HuT-102 and C91) and HTLV-1 negative (CEM and Jurkat) cell lines. MAIN METHODS: Cells were treated with TQ, As/IFN-α and combinations. Trypan blue and flow cytometry were used to investigate viability and cell cycle effects. Annexin-V staining, rhodamine assay and western blotting were used to determine apoptosis induction and changes in protein expression. Efficacy of single drugs and combinations were tested in adult T-cell leukemia (HuT-102) mouse xenograft model. KEY FINDINGS: TQ/As/IFN-α led to a more pronounced and synergistic time-dependent inhibitory effect on HTLV-I positive cells in comparison to As/IFN-α. While As/IFN-α combination was not effective against CEM or Jurkat cells, the triple combination TQ/As/IFN-α sensitized these two cell lines and led to a pronounced time-dependent inhibition of cell viability. TQ/As/IFN-α significantly induced apoptosis in all four cell lines and disrupted the mitochondrial membrane potential. Apoptosis was confirmed by the cleavage of caspase 3 and poly (ADP-ribose) polymerase (PARP), downregulation of Bcl-2 and XIAP and upregulation of Bax. TQ alone or in combination activated p53 in HTLV-1 positive cell lines. Strikingly, TQ/As/IFN-α resulted in a pronounced significant decrease in tumor volume in HuT-102 xenograft mouse model, as compared to separate treatments or double combination therapy. SIGNIFICANCE: Our results suggest a strong potential for TQ to enhance the drug targeting effects of the standard clinical drugs As and IFN-α against CD4+ malignant T-cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Arsênio/administração & dosagem , Benzoquinonas/administração & dosagem , Linhagem Celular Tumoral , Sinergismo Farmacológico , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Interferon-alfa/administração & dosagem , Células Jurkat , Leucemia-Linfoma de Células T do Adulto/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Front Bioeng Biotechnol ; 8: 605702, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33634079

RESUMO

The world continues to grapple with the devastating effects of the current COVID-19 pandemic. The highly contagious nature of this respiratory disease challenges advanced viral diagnostic technologies for rapid, scalable, affordable, and high accuracy testing. Molecular assays have been the gold standard for direct detection of the presence of the viral RNA in suspected individuals, while immunoassays have been used in the surveillance of individuals by detecting antibodies against SARS-CoV-2. Unlike molecular testing, immunoassays are indirect testing of the viral infection. More than 140 diagnostic assays have been developed as of this date and have received the Food and Drug Administration (FDA) emergency use authorization (EUA). Given the differences in assasy format and/or design as well as the lack of rigorous verification studies, the performance and accuracy of these testing modalities remain unclear. In this review, we aim to carefully examine commercialized and FDA approved molecular-based and serology-based diagnostic assays, analyze their performance characteristics and shed the light on their utility and limitations in dealing with the COVID-19 global public health crisis.

9.
Life Sci ; 232: 116628, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31278946

RESUMO

AIMS: Adult T-cell leukemia (ATL) is a mature T-cell neoplasm associated with human T-cell lymphotropic virus (HTLV-1) infection. Major limitations in Doxorubicin (Dox) chemotherapy are tumor resistance and severe drug complications. Here, we combined Thymoquinone (TQ) with low concentrations of Dox and determined anticancer effects against ATL in cell culture and animal model. MAIN METHODS: HTLV-1 positive (HuT-102) and HTLV-1 negative (Jurkat) CD4+ malignant T-cell lines were treated with TQ, Dox and combinations. Viability and cell cycle effects were determined by MTT assay and flow cytometry analysis, respectively. Combination effects on mitochondrial membrane potential and generation of reactive oxygen species (ROS) were assessed. Expression levels of key cell death proteins were investigated by western blotting. A mouse xenograft model of ATL in NOD/SCID was used for testing drug effects and tumor tissues were stained for Ki67 and TUNEL. KEY FINDINGS: TQ and Dox caused greater inhibition of cell viability and increased sub-G1 cells in both cell lines compared to Dox or TQ alone. The combination induced apoptosis by increasing ROS and causing disruption of mitochondrial membrane potential. Pretreatment with N-acetyl cysteine (NAC) or pan caspase inhibitor significantly inhibited the apoptotic response suggesting that cell death is ROS- and caspase-dependent. TQ and Dox combination reduced tumor volume in NOD/SCID mice more significantly than single treatments through enhanced apoptosis without affecting the survival of mice. SIGNIFICANCE: Our combination model offers the possibility to use up to twofold lower doses of Dox against ATL while exhibiting the same cancer inhibitory effects.


Assuntos
Benzoquinonas/farmacologia , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Leucemia-Linfoma de Células T do Adulto/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Drug Discov Today ; 23(5): 1089-1098, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29374534

RESUMO

Thymoquinone (TQ), the active ingredient of black seed, is a promising anticancer molecule that inhibits cancer cell growth and progression in vitro and in vivo. Despite the promising anticancer activities of TQ, its translation to the clinic is limited by its poor bioavailability and hydrophobicity. As such, we and others encapsulated TQ in nanoparticles to improve its delivery and limit undesirable cytotoxicity. These TQ-nanoparticle formulations showed improved anticancer and anti-inflammatory activities when compared with free TQ. Here, we provide an overview of the various TQ-nanoparticle formulations, highlight their superior efficacy and discuss up-to-date solutions to further enhance TQ bioavailability and anticancer activity, thus improving potential for clinical translation.


Assuntos
Antineoplásicos/administração & dosagem , Benzoquinonas/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Benzoquinonas/uso terapêutico , Humanos , Nanopartículas/uso terapêutico , Nanotecnologia
11.
Molecules ; 22(2)2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28208712

RESUMO

Considered as the second deadliest disease globally, cancer has captured the attention of researchers who have been trying with perseverance to decode its hidden aspects, to find new prognosis methods, and to develop better and more effective treatments. Plants have continuously offered an excess of unique secondary metabolites with remarkable biological applications. Alkaloids, one of the most abundant metabolites, constitute a large conglomerate of basic heterocyclic nitrogen-containing natural compounds which are normally produced by plants as toxic substances. Out of the 27,000 different alkaloids, more than 17,000 have displayed diversified pharmacological properties including anticancer activities. These metabolites have been classified either according to their chemical structures or their taxonomic origin. None of the researched alkaloids have been classified according to their molecular mechanism of action against cancer. In fact, only a fraction of the tremendous number of anticancer alkaloids has been copiously mentioned in journals. Here, we aim to provide a summary of the literature on some of the promising anticancer alkaloids that have not been well discussed previously and to classify them according to their molecular mechanisms of action. This review will provide a better understanding of the anticancer mechanisms of these promising natural products that are a rich reservoir for drug discovery.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Plantas Medicinais/química , Pesquisa , Transdução de Sinais/efeitos dos fármacos
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