Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Br J Clin Pharmacol ; 89(8): 2497-2507, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36965054

RESUMO

AIMS: Detection and characterization of idiosyncratic drug-induced liver injury (DILI) currently rely on standard liver tests, which are suboptimal in terms of specificity, sensitivity and prognosis. Therefore, DILI diagnosis can be delayed, with important consequences for the patient. In this study, we aimed to evaluate the potential of osteopontin, cytokeratin-18 (caspase-cleaved: ccK18 and total: K18), α-glutathione-S-transferase and microRNA-122 as new DILI biomarkers. METHODS: Serial blood samples were collected from 32 DILI and 34 non-DILI acute liver injury (ALI) cases and a single sample from 43 population controls without liver injury (HLC) and analysed using enzyme-linked immunosorbent assay (ELISA) or single-molecule arrays. RESULTS: All biomarkers differentiated DILI and ALI from HLC with an area under receiver operator characteristic curve (AUC) value of >0.75 but were less efficient in distinguishing DILI from ALI, with ccK18 (0.79) and K18 (0.76) demonstrating highest potential. However, the AUC improved considerably (0.98) for ccK18 when comparing DILI and a subgroup of autoimmune hepatitis cases. Cytokeratin-18, microRNA-122 and α-glutathione-S-transferase correlated well with traditional transaminases, while osteopontin correlated most strongly with the international normalized ratio (INR). CONCLUSIONS: ccK18 appears promising in distinguishing DILI from autoimmune hepatitis but less so from other forms of acute liver injury. Osteopontin demonstrates prognostic potential with higher levels detected in more severe cases regardless of aetiology.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Hepatite Autoimune , Hepatopatias , MicroRNAs , Humanos , Osteopontina , Queratina-18 , Prognóstico , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Fígado , Biomarcadores , Transferases , Glutationa
2.
Analyst ; 148(22): 5658-5666, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37807710

RESUMO

MicroRNAs (miRs) have emerged as promising biomarkers for diagnosing and predicting the prognosis of liver injury. This study aimed to compare the performance of two Luminex platforms, MAGPIX and FLEXMAP 3D, utilizing the innovative Dynamic Chemical Labelling (DCL) technology for direct detection and analysis of miR-122-5p in serum samples from patients with liver injury. Serum samples were collected from four patients with liver injury and four healthy controls. The levels of miR-122-5p were measured using the DCL method on both MAGPIX and FLEXMAP 3D platforms. The performance evaluation included the limit of detection (LOD), intra-assay and inter-assay precision, as well as accuracy. The results demonstrated that both platforms exhibited high sensitivity and specificity in detecting miR-122-5p in serum samples from patients with liver injury. However, FLEXMAP 3D indicated a lower LOD compared to MAGPIX. The precision of miR-122-5p detection was similar between the two platforms. In conclusion, both MAGPIX and FLEXMAP 3D Luminex platforms, in conjunction with DCL reagents, proved to be reliable and sensitive tools for detecting miR-122-5p in serum samples from patients with liver injury. Although both platforms were effective, FLEXMAP 3D exhibited slightly better performance, suggesting its preference for miR detection in clinical settings. These findings offer valuable insights for selecting the appropriate Luminex platform for miR detection in patients with liver injury and beyond.


Assuntos
MicroRNAs , Humanos , Biomarcadores , Prognóstico , Limite de Detecção
3.
Anal Chem ; 94(30): 10626-10635, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35866879

RESUMO

Barcoding and pooling cells for processing as a composite sample are critical to minimize technical variability in multiplex technologies. Fluorescent cell barcoding has been established as a standard method for multiplexing in flow cytometry analysis. In parallel, mass-tag barcoding is routinely used to label cells for mass cytometry. Barcode reagents currently used label intracellular proteins in fixed and permeabilized cells and, therefore, are not suitable for studies with live cells in long-term culture prior to analysis. In this study, we report the development of fluorescent palladium-based hybrid-tag nanotrackers to barcode live cells for flow and mass cytometry dual-modal readout. We describe the preparation, physicochemical characterization, efficiency of cell internalization, and durability of these nanotrackers in live cells cultured over time. In addition, we demonstrate their compatibility with standardized cytometry reagents and protocols. Finally, we validated these nanotrackers for drug response assays during a long-term coculture experiment with two barcoded cell lines. This method represents a new and widely applicable advance for fluorescent and mass-tag barcoding that is independent of protein expression levels and can be used to label cells before long-term drug studies.


Assuntos
Processamento Eletrônico de Dados , Corantes Fluorescentes , Linhagem Celular , Citometria de Fluxo/métodos , Corantes Fluorescentes/química , Proteômica
4.
Nanomedicine ; 24: 102120, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31676374

RESUMO

A novel chemical-based orthogonal bioconjugation strategy to produce tri-functionalized nanoparticles (NPs) an chemotherapy drug, doxorubicin (DOX), a near-infrared cyanine dye (Cy7) and CRGDK homing peptide, a peptide specifically binds to neuropilin-1 (Nrp-1) overexpressed on triple negative breast cancer (TNBC) cells, has been validated. These theranostic NPs have been evaluated in vitro and in vivo using an orthotopic xenotransplant mouse model using TNBC cells. In vitro assays show that theranostic NPs improve the therapeutic index in comparison with free DOX. Remarkably, in vivo studies showed preferred location of theranostic NPs in the tumor area reducing the volume at the same level than free DOX while presenting lower side effects. This multifunctionalized theranostic nanodevice based on orthogonal conjugation strategies could be a good candidate for the treatment and monitoring of Nrp-1 overexpressing tumors. Moreover, this versatile nanodevice can be easily adapted to treat and monitor different cancer types by adapting the conjugation strategy.


Assuntos
Carbocianinas , Doxorrubicina , Sistemas de Liberação de Medicamentos , Nanopartículas , Peptídeos , Nanomedicina Teranóstica , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Carbocianinas/química , Carbocianinas/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Nanopartículas/química , Nanopartículas/uso terapêutico , Proteínas de Neoplasias/metabolismo , Neuropilina-1/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Acc Chem Res ; 45(7): 1140-52, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22390230

RESUMO

Nucleic acids are the foundation stone of all cellular processes. Consequently, the use of DNA or RNA to treat genetic and acquired disorders (so called gene therapy) offers enormous potential benefits. The restitution of defective genes or the suppression of malignant genes could target a range of diseases, including cancers, inherited diseases (cystic fibrosis, muscular dystrophy, etc.), and viral infections. However, this strategy has a major barrier: the size and charge of nucleic acids largely restricts their transit into eukaryotic cells. Potential strategies to solve this problem include the use of a variety of natural and synthetic nucleic acid carriers. Driven by the aim and ambition of translating this promising therapeutic approach into the clinic, researchers have been actively developing advanced delivery systems for nucleic acids for more than 20 years. A decade ago we began our investigations of solid-phase techniques to construct families of novel nucleic acid carriers for transfection. We envisaged that the solid-phase synthesis of polycationic dendrimers and derivatized polyamimes would offer distinct advantages over solution phase techniques. Notably in solid phase synthesis we could take advantage of mass action and streamlined purification procedures, while simplifying the handling of compounds with high polarities and plurality of functional groups. Parallel synthesis methods would also allow rapid access to libraries of compounds with improved purities and yields over comparable solution methodologies and facilitate the development of structure activity relationships. We also twisted the concept of the solid-phase support on its head: we devised miniaturized solid supports that provided an innovative cell delivery vehicle in their own right, carrying covalently conjugated cargos (biomolecules) into cells. In this Account, we summarize the main outcomes of this series of chemically related projects.


Assuntos
Ácidos Nucleicos/metabolismo , Arginina/química , DNA/química , DNA/metabolismo , Dendrímeros/química , Humanos , Lipídeos/química , Microesferas , Ácidos Nucleicos/química , Poliaminas/química , RNA/química , RNA/metabolismo , Técnicas de Síntese em Fase Sólida , Transfecção
7.
Biosens Bioelectron ; 219: 114770, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36270082

RESUMO

The detection of repetitive sequences with single-base resolution is becoming increasingly important aiming to understand the biological implications of genomic variation in these sequences. However, there is a lack of techniques to experimentally validate sequencing data from repetitive sequences obtained by Next-Generation Sequencing methods, especially in the case of Single-Nucleotide Variations (SNVs). That is one of the reasons why repetitive sequences have been poorly studied and excluded from most genomic studies. Therefore, in addition to sequencing data, there is an urgent need for efficient validation methods of genomic variation in these sequences. Herein we report the development of chemFISH, an alternative method for the detection of SNVs in repetitive sequences. ChemFISH is an innovative method based on dynamic chemistry labelling and abasic Peptide Nucleic Acid (PNA) probes to detect in situ the α-satellite DNA, organized in tandem repeats, with single-base resolution in a direct and rapid reaction. With this approach, we detected by microscopy the α-satellite DNA in a variety of human cell lines, we quantified the detection showing a low coefficient of variation among samples (13.16%-25.33%) and we detected single-base specificity with high sensitivity (82.41%-88.82%). These results indicate that chemFISH can serve as a rapid method to validate previously detected SNVs in sequencing data, as well as to find novel SNVs in repetitive sequences. Furthermore, the versatile chemistry behind chemFISH can lead to develop novel molecular assays for the in situ detection of nucleic acids.

8.
Biosens Bioelectron ; 230: 115268, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37030262

RESUMO

The COVID-19 pandemic has highlighted the need for innovative approaches to its diagnosis. Here we present CoVradar, a novel and simple colorimetric method that combines nucleic acid analysis with dynamic chemical labeling (DCL) technology and the Spin-Tube device to detect SARS-CoV-2 RNA in saliva samples. The assay includes a fragmentation step to increase the number of RNA templates for analysis, using abasic peptide nucleic acid probes (DGL probes) immobilized to nylon membranes in a specific dot pattern to capture RNA fragments. Duplexes are formed by labeling complementary RNA fragments with biotinylated SMART bases, which act as templates for DCL. Signals are generated by recognizing biotin with streptavidin alkaline phosphatase and incubating with a chromogenic substrate to produce a blue precipitate. CoVradar results are analysed by CoVreader, a smartphone-based image processing system that can display and interpret the blotch pattern. CoVradar and CoVreader provide a unique molecular assay capable of detecting SARS-CoV-2 viral RNA without the need for extraction, preamplification, or pre-labeling steps, offering advantages in terms of time (∼3 h/test), cost (∼€1/test manufacturing cost) and simplicity (does not require large equipment). This solution is also promising for developing assays for other infectious diseases.


Assuntos
Técnicas Biossensoriais , COVID-19 , Aplicativos Móveis , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , RNA Viral/genética , RNA Viral/análise , Pandemias , Técnicas Biossensoriais/métodos , Smartphone , Técnicas de Amplificação de Ácido Nucleico/métodos
9.
Talanta ; 226: 122092, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676649

RESUMO

Nucleic acid-based molecular diagnosis has gained special importance for the detection and early diagnosis of genetic diseases as well as for the control of infectious disease outbreaks. The development of systems that allow for the detection and analysis of nucleic acids in a low-cost and easy-to-use way is of great importance. In this context, we present a combination of a nanotechnology-based approach with the already validated dynamic chemical labeling (DCL) technology, capable of reading nucleic acids with single-base resolution. This system allows for the detection of biotinylated molecular products followed by simple detection using a standard flow cytometer, a widely used platform in clinical and molecular laboratories, and therefore, is easy to implement. This proof-of-concept assay has been developed to detect mutations in KRAS codon 12, as these mutations are highly important in cancer development and cancer treatments.


Assuntos
Ácidos Nucleicos , Ácidos Nucleicos Peptídicos , Citometria de Fluxo , Mutação , Nanotecnologia , Ácidos Nucleicos/genética
10.
Nanoscale ; 13(6): 3500-3511, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33560282

RESUMO

In this manuscript, we report the development of a versatile, robust, and stable targeting nanocarrier for active delivery. This nanocarrier is based on bifunctionalized polymeric nanoparticles conjugated to a monoclonal antibody that allows for active targeting of either (i) a fluorophore for tracking or (ii) a drug for monitoring specific cell responses. This nanodevice can efficiently discriminate between cells in coculture based on the expression levels of cell surface receptors. As a proof of concept, we have demonstrated efficient delivery using a broadly established cell surface receptor as the target, the epidermal growth factor receptor (EGFR), which is overexpressed in several types of cancers. Additionally, a second validation of this nanodevice was successfully carried out using another cell surface receptor as the target, the cluster of differentiation 147 (CD147). Our results suggest that this versatile nanocarrier can be expanded to other cell receptors and bioactive cargoes, offering remarkable discrimination efficiency between cells with different expression levels of a specific marker. This work supports the ability of nanoplatforms to boost and improve the progress towards personalized medicine.


Assuntos
Portadores de Fármacos , Nanopartículas , Linhagem Celular Tumoral , Técnicas de Cocultura , Sistemas de Liberação de Medicamentos , Polímeros
11.
Polymers (Basel) ; 12(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492910

RESUMO

Despite the large number of polymeric nanodelivery systems that have been recently developed, there is still room for improvement in terms of therapeutic efficiency. Most reported nanodevices for controlled release are based on drug encapsulation, which can lead to undesired drug leakage with a consequent reduction in efficacy and an increase in systemic toxicity. Herein, we present a strategy for covalent drug conjugation to the nanodevice to overcome this drawback. In particular, we characterize and evaluate an effective therapeutic polymeric PEGylated nanosystem for controlled pH-sensitive drug release on a breast cancer (MDA-MB-231) and two lung cancer (A549 and H520) cell lines. A significant reduction in the required drug dose to reach its half maximal inhibitory concentration (IC50 value) was achieved by conjugation of the drug to the nanoparticles, which leads to an improvement in the therapeutic index by increasing the efficiency. The genotoxic effect of this nanodevice in cancer cells was confirmed by nucleus histone H2AX specific immunostaining. In summary, we successfully characterized and validated a pH responsive therapeutic polymeric nanodevice in vitro for controlled anticancer drug release.

12.
Cancer Discov ; 10(11): 1635-1644, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33037026

RESUMO

Despite major therapeutic progress, most advanced solid tumors are still incurable. Cancer interception is the active way to combat cancer onset, and development of this approach within high-risk populations seems a logical first step. Until now, strategies for the identification of high-risk subjects have been based on low-sensitivity and low-specificity assays. However, new liquid biopsy assays, "the Rosetta Stone of the new biomedicine era," with the ability to identify circulating biomarkers with unprecedented sensitivity, promise to revolutionize cancer management. This review focuses on novel liquid biopsy approaches and the applications to cancer interception. Cancer interception involves the identification of biomarkers associated with developing cancer, and includes genetic and epigenetic alterations, as well as circulating tumor cells and circulating epithelial cells in individuals at risk, and the implementation of therapeutic strategies to prevent the beginning of cancer and to stop its development. Large prospective studies are needed to confirm the potential role of liquid biopsy for early detection of precancer lesions and tumors.


Assuntos
Biópsia Líquida/métodos , Neoplasias/prevenção & controle , Medicina de Precisão/métodos , Humanos
13.
Crit Rev Oncol Hematol ; 151: 102978, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32428812

RESUMO

Precision medicine was born with the development of new diagnostic techniques and targeted drugs, yielding better outcomes in cancer care. With the evolution and increasing sensitivity for detecting oncogenic drivers, liquid biopsies (LBs), specifically cell-free DNA (cfDNA) analysis, have been proposed as a minimally-invasive technique for genomic profiling. Ranging from sequencing techniques to PCR-based methods and other more complex strategies, this approach, currently applicable in some solid tumors with robust evidence, is showing promising opportunities in other cancers. However, difficulties in validating their clinical utility exist within limitation at different levels among several techniques, reporting of the results, lack of appropriate clinical trial designs, and unknown economic impact. One of the aims of the ISLB is to create recommendations to develop reliable and sustainable diagnostic, prognostic and predictive tools using LBs. This paper is addressing these objectives, helping the healthcare providers and scientific community to understand the potential of LB.


Assuntos
Ácidos Nucleicos Livres , Biópsia Líquida , Neoplasias/patologia , Medicina de Precisão/métodos , Biomarcadores Tumorais , Humanos , Sociedades Médicas
14.
Lab Chip ; 9(3): 397-403, 2009 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-19156288

RESUMO

In this study, polymer microarrays were used for the rapid identification of polymer substrates upon which a suspension cell line would both adhere and proliferate giving a detailed and rapid understanding of cell-biomaterial interactions. Analysis demonstrated that suspension K562 human erythroleukemic cells, which normally grow in suspension, adhered and proliferated on several different polymers. Phenotypic and transcriptomic analysis techniques allowed examination of the interaction between cells and polymers permitting the elucidation of putative links between phenotypic responses to cell-biomaterial interactions and global gene expression.


Assuntos
Materiais Biocompatíveis/metabolismo , Adesão Celular , Análise em Microsséries/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Polímeros/metabolismo , Resinas Acrílicas/metabolismo , Adesão Celular/genética , Proliferação de Células , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Células K562 , Microscopia Acústica , Fenótipo , Poliuretanos/metabolismo , Reprodutibilidade dos Testes
15.
Sci Rep ; 9(1): 3696, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842455

RESUMO

Leishmaniasis and Chagas disease are endemic in many countries, and re-emerging in the developed countries. A rapid and accurate diagnosis is important for early treatment for reducing the duration of infection as well as for preventing further potential health complications. In this work, we have developed a novel colorimetric molecular assay that integrates nucleic acid analysis by dynamic chemistry (ChemNAT) with reverse dot-blot hybridization in an array format for a rapid and easy discrimination of Leishmania major and Trypanosoma cruzi. The assay consists of a singleplex PCR step that amplifies a highly homologous DNA sequence which encodes for the RNA component of the large ribosome subunit. The amplicons of the two different parasites differ between them by single nucleotide variations, known as "Single Nucleotide Fingerprint" (SNF) markers. The SNF markers can be easily identified by naked eye using a novel micro Spin-Tube device "Spin-Tube", as each of them creates a specific spot pattern. Moreover, the direct use of ribosomal RNA without requiring the PCR pre-amplification step is also feasible, further increasing the simplicity of the assay. The molecular assay delivers sensitivity capable of identifying up to 8.7 copies per µL with single mismatch specificity. The Spin-Tube thus represents an innovative solution providing benefits in terms of time, cost, and simplicity, all of which are crucial for the diagnosis of infectious disease in developing countries.


Assuntos
Mapeamento de Nucleotídeos/métodos , Trypanosomatina/genética , Trypanosomatina/isolamento & purificação , Doença de Chagas/diagnóstico , Doença de Chagas/genética , Colorimetria/métodos , Leishmania major/genética , Leishmaniose/diagnóstico , Leishmaniose/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico/genética , Sensibilidade e Especificidade , Trypanosoma cruzi/genética
16.
Chem Commun (Camb) ; (11): 1317-9, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-18389119

RESUMO

Polymer hydrogel microarrays were fabricated by inkjet printing of monomers and initiator, allowing up to 1800 individual polymer features to be printed on a single glass slide.


Assuntos
Hidrogéis/química , Análise em Microsséries/instrumentação , Nanotecnologia , Vidro , Processamento de Imagem Assistida por Computador , Indicadores e Reagentes , Polímeros/síntese química , Impressão
17.
Nanomedicine (Lond) ; 12(13): 1591-1605, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28513331

RESUMO

AIM: To develop an efficient nanotechnology fluorescence-based method to track cell proliferation to avoid the limitations of current cell-labeling dyes. MATERIAL & METHODS: Synthesis, PEGylation, bifunctionalization and labeling with a fluorophore (Cy5) of 200 nm polystyrene nanoparticles (NPs) were performed. These NPs were characterized and assessed for in vitro long-term monitoring of cell proliferation. RESULTS: The optimization and validation of this method to track long-term cell proliferation assays have been achieved with high reproducibility, without cell cycle disruption. This method has been successfully applied in several adherent and suspension cells including hard-to-transfect cells and isolated human primary lymphocytes. CONCLUSION: A novel approach to track efficiently cellular proliferation by flow cytometry using fluorescence labeled NPs has been successfully developed. [Formula: see text].


Assuntos
Proliferação de Células , Rastreamento de Células/métodos , Corantes Fluorescentes/química , Nanopartículas/química , Poliestirenos/química , Ciclo Celular , Linhagem Celular Tumoral , Estudos de Viabilidade , Citometria de Fluxo , Fluorescência , Humanos , Leucócitos Mononucleares/citologia , Reprodutibilidade dos Testes , Coloração e Rotulagem , Propriedades de Superfície , Transfecção
19.
Talanta ; 161: 489-496, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27769437

RESUMO

Over the last decade, circulating microRNAs have received attention as diagnostic and prognostic biomarkers. In particular, microRNA122 has been demonstrated to be an early and more sensitive indicator of drug-induced liver injury than the widely used biomarkers such as alanine aminotransferase and aspartate aminotransferase. Recently, microRNA122 has been used in vitro to assess the cellular toxicity of new drugs and as a biomarker for the development of a rapid test for drug overdose/liver damage. In this proof-of-concept study, we report a PCR-free and label-free detection method that has a limit of detection (3 standard deviations) of 15 fmoles of microRNA122, by integrating a dynamic chemical approach for "Single Nucleobase Labelling" with a bead-based platform (Luminex®) thereby, in principle, demonstrating the exciting prospect of rapid and accurate profiling of any microRNAs related to diseases and toxicology.


Assuntos
MicroRNAs/análise , Biomarcadores , Limite de Detecção , Microesferas , Sondas de Ácido Nucleico , Ácidos Nucleicos Peptídicos
20.
Chem Commun (Camb) ; (11): 1384-6, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15756311

RESUMO

Enzymatic modifications of split and mix libraries were followed by "pulling down" onto a 2-dimensional DNA microarray, via PNA tagging; this allowed complete library interrogation of all members of the split and mix library.


Assuntos
Técnicas de Química Combinatória/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Ácidos Nucleicos Peptídicos , Estrutura Molecular , Peptídeo Hidrolases/química , Proteínas Proto-Oncogênicas c-abl/química , Soluções/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA