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1.
ACS Sens ; 9(3): 1272-1279, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38265266

RESUMO

In recent years, wearable sensors have revolutionized health monitoring by enabling continuous, real-time tracking of human health and performance. These noninvasive devices are usually designed to monitor human physical state and biochemical markers. However, enhancing their functionalities often demands intricate customization by designers and additional expenses for users. Here, we present a strategy using assembled modular circuits to customize health monitoring wearables. The modular circuits can be effortlessly reconfigured to meet various specific requirements, facilitating the incorporation of diverse functions at a lower cost. To validate this approach, modular circuits were employed to develop four distinct systems for in vitro evaluations. These systems enabled the detection of sweat biomarkers and physical signals under various scenarios, including sedentary state, exercise, and daily activities with or without incorporating iontophoresis to induce sweat. Four key sweat markers (K+, Ca2+, Na+, and pH) and three essential physical indicators (heart rate, blood oxygen levels, and skin temperature) are selected as the detection targets. Commercial methods were also used to evaluate the potential for effective health monitoring with our technique. This reconfigurable modular wearable (ReModuWear) system promises to provide more easy-to-use and comprehensive health assessments. Additionally, it may contribute to environmental sustainability by reusing modules.


Assuntos
Suor , Dispositivos Eletrônicos Vestíveis , Humanos , Suor/metabolismo , Monitorização Fisiológica , Íons , Sódio/metabolismo , Biomarcadores/metabolismo
2.
Talanta ; 269: 125444, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042143

RESUMO

Signal transduction mediated by epidermal growth factor receptor (EGFR) gene affects the proliferation, invasion, metastasis, and angiogenesis of tumor cells. In particular, non-small cell lung cancer (NSCLC) patients with increased in copy number of EGFR gene are often sensitive to tyrosine kinase inhibitors. Despite being the standard for detecting EGFR amplification in the clinic, fluorescence in situ hybridization (FISH) traditionally involves repetitive and complex benchtop procedures that are not only time consuming but also require well-trained personnel. To address these limitations, we develop a digital microfluidics-based FISH platform (DMF-FISH) that automatically implements FISH operations. This system mainly consists of a DMF chip for reagent operation, a heating array for temperature control and a signal processing system. With the capability of automatic droplet handling and efficient temperature control, DMF-FISH performs cell digestion, gradient elution, hybridization and DAPI staining without manual intervention. In addition to operational feasibility, DMF-FISH yields comparable performance with the benchtop FISH protocol but reducing the consumption of DNA probe by 87 % when tested with cell lines and clinical samples. These results highlight unique advantages of the fully automated DMF-FISH system and thus suggest its great potential for clinical diagnosis and personalized therapy of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Amplificação de Genes , Receptores ErbB/genética , Receptores ErbB/metabolismo , Hibridização in Situ Fluorescente/métodos , Microfluídica , Dosagem de Genes , Mutação
3.
Biosensors (Basel) ; 12(6)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35735518

RESUMO

An organ-on-a-chip is a device that combines micro-manufacturing and tissue engineering to replicate the critical physiological environment and functions of the human organs. Therefore, it can be used to predict drug responses and environmental effects on organs. Microfluidic technology can control micro-scale reagents with high precision. Hence, microfluidics have been widely applied in organ-on-chip systems to mimic specific organ or multiple organs in vivo. These models integrated with various sensors show great potential in simulating the human environment. In this review, we mainly introduce the typical structures and recent research achievements of several organ-on-a-chip platforms. We also discuss innovations in models applied to the fields of pharmacokinetics/pharmacodynamics, nano-medicine, continuous dynamic monitoring in disease modeling, and their further applications in other fields.


Assuntos
Dispositivos Lab-On-A-Chip , Microfluídica , Desenvolvimento de Medicamentos , Humanos , Engenharia Tecidual
4.
Biosensors (Basel) ; 12(5)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35624646

RESUMO

The gingival epithelium-capillary interface is a unique feature of periodontal soft tissue, preserving periodontal tissue homeostasis and preventing microorganism and toxic substances from entering the subepithelial tissue. However, the function of the interface is disturbed in periodontitis, and mechanisms of the breakdown of the interface are incompletely understood. To address these limitations, we developed a microfluidic epithelium-capillary barrier with a thin culture membrane (10 µm) that closely mimics the in vivo gingival epithelial barrier with an immune micro-environment. To test the validity of the fabricated gingival epithelial barrier model, epithelium-capillary interface-on-a-chip was cultured with human gingival epithelial cells (HGECs) and human vascular endothelial cells (HUVEC). Their key properties were tested using optical microscope, transepithelial/transendothelial electrical resistance (TEER), and permeability assays. The clear expression of VE-cadherin revealed the tight junctions in endothelial cells. Live/dead assays indicated a high cell viability, and the astrocytic morphology of HGE cells was confirmed by F-actin immunostaining. By the third day of cell culture, TEER levels typically exceeded in co-cultures. The resultant permeability coefficients showed a significant difference between 70 kDa and 40 kDa FITC-dextran. The expression of protein intercellular cell adhesion molecule (ICAM-1) and human beta defensin-2 (HBD2) decreased when exposed to TNF-α and LPS, but recovered with the NF-κB inhibitor treatment- Pyrrolidinedithiocarbamic acid (PDTC), indicating the stability of the fabricated chip. These results demonstrate that the developed epithelium-capillary interface system is a valid model for studying periodontal soft tissue function and drug delivery.


Assuntos
Células Endoteliais , Dispositivos Lab-On-A-Chip , Células Endoteliais/metabolismo , Epitélio/metabolismo , Humanos , Inflamação , Junções Íntimas
5.
N Engl J Med ; 386(16): 1519-1531, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35443108

RESUMO

BACKGROUND: The combination of ivosidenib - an inhibitor of mutant isocitrate dehydrogenase 1 (IDH1) - and azacitidine showed encouraging clinical activity in a phase 1b trial involving patients with newly diagnosed IDH1-mutated acute myeloid leukemia. METHODS: In this phase 3 trial, we randomly assigned patients with newly diagnosed IDH1-mutated acute myeloid leukemia who were ineligible for intensive induction chemotherapy to receive oral ivosidenib (500 mg once daily) and subcutaneous or intravenous azacitidine (75 mg per square meter of body-surface area for 7 days in 28-day cycles) or to receive matched placebo and azacitidine. The primary end point was event-free survival, defined as the time from randomization until treatment failure (i.e., the patient did not have complete remission by week 24), relapse from remission, or death from any cause, whichever occurred first. RESULTS: The intention-to-treat population included 146 patients: 72 in the ivosidenib-and-azacitidine group and 74 in the placebo-and-azacitidine group. At a median follow-up of 12.4 months, event-free survival was significantly longer in the ivosidenib-and-azacitidine group than in the placebo-and-azacitidine group (hazard ratio for treatment failure, relapse from remission, or death, 0.33; 95% confidence interval [CI], 0.16 to 0.69; P = 0.002). The estimated probability that a patient would remain event-free at 12 months was 37% in the ivosidenib-and-azacitidine group and 12% in the placebo-and-azacitidine group. The median overall survival was 24.0 months with ivosidenib and azacitidine and 7.9 months with placebo and azacitidine (hazard ratio for death, 0.44; 95% CI, 0.27 to 0.73; P = 0.001). Common adverse events of grade 3 or higher included febrile neutropenia (28% with ivosidenib and azacitidine and 34% with placebo and azacitidine) and neutropenia (27% and 16%, respectively); the incidence of bleeding events of any grade was 41% and 29%, respectively. The incidence of infection of any grade was 28% with ivosidenib and azacitidine and 49% with placebo and azacitidine. Differentiation syndrome of any grade occurred in 14% of the patients receiving ivosidenib and azacitidine and 8% of those receiving placebo and azacitidine. CONCLUSIONS: Ivosidenib and azacitidine showed significant clinical benefit as compared with placebo and azacitidine in this difficult-to-treat population. Febrile neutropenia and infections were less frequent in the ivosidenib-and-azacitidine group than in the placebo-and-azacitidine group, whereas neutropenia and bleeding were more frequent in the ivosidenib-and-azacitidine group. (Funded by Agios Pharmaceuticals and Servier Pharmaceuticals; AGILE ClinicalTrials.gov number, NCT03173248.).


Assuntos
Antineoplásicos , Azacitidina , Leucemia Mieloide Aguda , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Azacitidina/administração & dosagem , Azacitidina/efeitos adversos , Azacitidina/uso terapêutico , Neutropenia Febril/induzido quimicamente , Glicina/análogos & derivados , Humanos , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucopenia/induzido quimicamente , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Piridinas/uso terapêutico , Recidiva
6.
Biom J ; 64(2): 198-224, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35152457

RESUMO

Targeted therapies tend to have biomarker defined subgroups that derive differential efficacy from treatments. This article corrects three prevailing oversights in stratified analyses comparing treatments in randomized controlled trials (RCTs) with binary and time-to-event outcomes: 1.Using efficacy measures such as odds ratio (OR) and hazard ratio (HR) can make a prognostic biomarker appear predictive, targeting wrong patients, because the inference is affected by a confounding/covert factor even with ignorable treatment assignment in an RCT. As shown analytically and with real immunotherapy patient level data, OR and HR cannot meet the causal Estimand requirement of ICH E9R1. 2.Mixing efficacy in subgroups by prevalence, the prevailing practice, can give misleading results also, for any efficacy measured as a ratio. However, mixing relative response (RR) and ratio of median (RoM) survival times by the prognostic effect, the confounding/covert factor hiding in plain sight, will give causal inference in an RCT. 3.Effects in subgroups should not be mixed on the logarithmic scale, because it creates an artificial Estimand for the whole population which changes depending on how the population is divided into subgroups. Current computer package implementations contain all these oversights. Probabilities, including survival curve probabilities, naturally average within each treatment arm by prevalence. The subgroup mixable estimation (SME) principle fixes the oversights by first averaging probabilities (not their logarithms) within each treatment arm, then computing simultaneous confidence intervals for ratio efficacy in subgroups and their mixtures based on rigorous mathematical derivation, to finally provide causal inference in the form of apps.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Modelos de Riscos Proporcionais
7.
Biosensors (Basel) ; 11(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208844

RESUMO

In recent years, nanopore technology has become increasingly important in the field of life science and biomedical research. By embedding a nano-scale hole in a thin membrane and measuring the electrochemical signal, nanopore technology can be used to investigate the nucleic acids and other biomacromolecules. One of the most successful applications of nanopore technology, the Oxford Nanopore Technology, marks the beginning of the fourth generation of gene sequencing technology. In this review, the operational principle and the technology for signal processing of the nanopore gene sequencing are documented. Moreover, this review focuses on the applications using nanopore gene sequencing technology, including the diagnosis of cancer, detection of viruses and other microbes, and the assembly of genomes. These applications show that nanopore technology is promising in the field of biological and biomedical sensing.


Assuntos
Nanoporos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Tecnologia , Vírus
8.
Br J Clin Pharmacol ; 87(4): 1824-1838, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32986868

RESUMO

AIMS: To evaluate the safety, pharmacokinetics and pharmacodynamics of single- and multiple-rising doses (MRDs) of BI 705564 and establish proof of mechanism. METHODS: BI 705564 was studied in 2 placebo-controlled, Phase I clinical trials testing single-rising doses (1-160 mg) and MRDs (1-80 mg) of BI 705564 over 14 days in healthy male volunteers. Blood samples were analysed for BI 705564 plasma concentration, Bruton's tyrosine kinase (BTK) target occupancy (TO) and CD69 expression in B cells stimulated ex vivo. A substudy was conducted in allergic, otherwise healthy, MRD participants. Safety was assessed in both studies. RESULTS: All doses of BI 705564 were well tolerated. Geometric mean BI 705564 plasma terminal half-life ranged from 10.1 to 16.9 hours across tested doses, with no relevant accumulation after multiple dosing. Doses ≥20 mg resulted in ≥85% average TO that was maintained for ≥48 hours after single-dose administration. Functional effects of BTK signalling were demonstrated by dose-dependent inhibition of CD69 expression. In allergic participants, BI 705564 treatment showed a trend in wheal size reduction in a skin prick test and complete inhibition of basophil activation. Mild bleeding-related adverse events were observed with BI 705564; bleeding time increased in 1/12 participants (8.3%) who received placebo vs 26/48 (54.2%) treated with BI 705564. CONCLUSION: BI 705564 showed efficient target engagement through durable TO and inhibition of ex vivo B-cell activation, and proof of mechanism through effects on allergic skin responses. Mild bleeding-related adverse events were probably related to inhibition of platelet aggregation by BTK inhibition.


Assuntos
Linfócitos B , Agregação Plaquetária , Tirosina Quinase da Agamaglobulinemia , Voluntários Saudáveis , Humanos , Masculino , Inibidores de Proteínas Quinases/efeitos adversos , Transdução de Sinais
9.
Pharm Stat ; 19(6): 787-802, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32573051

RESUMO

For pediatric drug development, the clinical effectiveness of the study medication for the adult population has already been demonstrated. Given the fact that it is usually not feasible to enroll a large number of pediatric patients, appropriately leveraging historical adult data into pediatric evaluation may be critical to success of pediatric drug development. In this manuscript, we propose a new empirical Bayesian approach, profile Bayesian estimation, to dynamically borrow adult information to the evaluation of treatment effect in pediatric patients. The new approach demonstrates an attractive balance between type I error control and power gain under the transfer-ability assumption that the pediatric treatment effect size may differ from the adult treatment effect size. The decision making boundary mimics the real-world practice in pediatric drug development. In addition, the posterior mean of the proposed empirical profile Bayesian is an unbiased estimator of the true pediatric treatment effect. We compare our approach to robust mixture prior with prior weight for informative borrowing set to 0.5 or 0.9, regular Bayesian approach, and frequentist for both type I error and power.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Desenvolvimento de Medicamentos/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Projetos de Pesquisa/estatística & dados numéricos , Fatores Etários , Teorema de Bayes , Simulação por Computador , Interpretação Estatística de Dados , Humanos , Modelos Estatísticos , Análise Numérica Assistida por Computador
10.
Biosci Rep ; 39(2)2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30674640

RESUMO

Understanding cell migration in a 3D microenvironment is essential as most cells encounter complex 3D extracellular matrix (ECM) in vivo Although interactions between cells and ECM have been studied previously on 2D surfaces, cell migration studies in 3D environment are still limited. To investigate cell migration under various degrees of confinements and coating conditions, 3D platforms with micropost arrays and controlled fibronectin (FN) protein coating were developed. MC3T3-E1 cells spread and contacted the top surface of microposts if FN was coated on top. When FN was coated all over the microposts, cells were trapped between microposts with 3 µm spacing and barely moved. As the spacing between microposts increased from 3 to 5 µm, cells became elongated with limited cell movement of 0.18 µm/min, slower than the cell migration speed of 0.40 µm/min when cells moved on top. When cells were trapped in between the microposts, cell nuclei were distorted and actin filaments formed along the sidewalls of microposts. With the addition of a top cover to introduce cell confinement, the cell migration speed was 0.23 and 0.84 µm/min when the channel height was reduced from 20 to 10 µm, respectively. Cell traction force was monitored at on the top and bottom microposts with 10 µm channel height. These results show that the MC3T3-E1 cell morphology, migration speed, and movement position were affected by surface coating and physical confinement, which will provide significant insights for in vivo cell migration within a 3D ECM.


Assuntos
Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Movimento Celular/fisiologia , Osteoblastos/citologia , Animais , Linhagem Celular , Núcleo Celular/patologia , Citoesqueleto/ultraestrutura , Matriz Extracelular , Fibronectinas , Camundongos , Microscopia Eletrônica de Varredura , Imagem com Lapso de Tempo
11.
RSC Adv ; 9(15): 8575-8584, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35518671

RESUMO

Three-dimensional (3D) cell migrations are regulated by force interactions between cells and a 3D extracellular matrix (ECM). Mapping the 3D traction force generated by cells on the surrounding ECM with controlled confinement and contact area will be useful in understanding cell migration. In this study, double-sided micropost arrays were fabricated. The cell traction force was mapped by microposts on the top and bottom of opposing surfaces with a controlled separating distance to create different confinements. The density of micropost arrays was modified to investigate the effect of cell contact area on 3D traction force development. Using MC3T3-E1 osteoblastic cells, the leading traction force was found to increase with additional contact surface on the top. Summing force vectors on both surfaces, a large force imbalance was found from the leading to trailing regions for fast migrating cells. With 10 µm separation and densely arranged microposts, the traction force on the top surface was the largest at 28.6 ± 2.5 nN with the highest migration speed of 0.61 ± 0.07 µm min-1. Decreasing the density of the top micropost arrays resulted in a reduced traction force on the top and lower migration speed. With 15 µm separation, the cell traction force on the top and migration speed further decreased simultaneously. These results revealed traction force development on 3D ECM with varied degrees of confinement and contact area, which is important in regulating 3D cell migration.

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