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1.
J Hazard Mater ; 472: 134311, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38691989

RESUMO

This study proposes a predictive model for assessing adsorber performance in gas purification processes, specifically targeting the removal of chemical warfare agents (CWAs) using breakthrough curve analysis. Conventional parameter estimation methods, such as Brunauer-Emmett-Teller analysis, encounter challenges due to the limited availability of kinetic and equilibrium data for CWAs. To overcome these challenges, we implement a Bayesian parametric inference method, facilitating direct parameter estimation from breakthrough curves. The model's efficacy is confirmed by applying it to H2S purification in a fixed-bed setup, where predicted breakthrough curves aligned closely with previous experimental and numerical studies. Furthermore, the model is applied to sarin with ASZM-TEDA carbon, estimating key parameters that could not be assessed through conventional experimental techniques. The reconstructed breakthrough curves closely match actual measurements, highlighting the model's accuracy and robustness. This study not only enhances filter performance prediction for CWAs but also offers a streamlined approach for evaluating gas purification technologies under limited experimental data conditions.

2.
Mol Biol Rep ; 51(1): 305, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38361124

RESUMO

BACKGROUND: Pectolinarigenin (PEC) is a flavone extracted from Cirsium, and because it has anti-inflammatory properties, anti-cancer research is also being conducted. The objective of this work was to find out if PEC is involved in tumor control and which pathways it regulates in vivo and in vitro. METHODS: AGS cell lines were xenografted into BALB/c nude mice to create tumors, and PEC was administered intraperitoneally to see if it was involved in tumor control. Once animal testing was completed, tumor proteins were isolated and identified using LC-MS analysis, and gene ontology of the found proteins was performed. RESULTS: Body weight and hematological measurements on the xenograft mice model demonstrated that PEC was not harmful to non-cancerous cells. We found 582 proteins in tumor tissue linked to biological reactions such as carcinogenesis and cell death signaling. PEC regulated 6 out of 582 proteins in vivo and in vitro in the same way. CONCLUSION: Our findings suggested that PEC therapy may inhibit tumor development in gastric cancer (GC), and proteomic research gives fundamental information about proteins that may have great promise as new therapeutic targets in GC.


Assuntos
Apoptose , Cromonas , Neoplasias Gástricas , Humanos , Animais , Camundongos , Camundongos Nus , Xenoenxertos , Proteômica , Linhagem Celular Tumoral , Neoplasias Gástricas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proliferação de Células
3.
ACS Sens ; 8(5): 1980-1988, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37098135

RESUMO

Integrated wearable bioelectronic health monitoring systems have revealed new possibilities for collecting personalized physiological information. Wearable sweat sensors have the potential to noninvasively measure valuable biomarkers. Mapping sweat and skin-temperature throughout the body can provide detailed information on the human body. However, existing wearable systems cannot evaluate such data. Here, we report a multifunctional wearable platform that can wirelessly measure local sweat loss, sweat chloride concentration, and skin temperature. The approach combines a reusable electronics module to monitor skin temperature and a microfluidic module for monitoring sweat loss and sweat chloride concentration. The miniaturized electronic system takes temperature measurements from the skin and wirelessly transmits the obtained data to a user device using Bluetooth technology. In contrast, the microfluidic system provides accurate colorimetric analysis of the chloride concentration and sweat loss. Thus, this integrated wearable system has great application potential in individualized health management systems for sports researchers and competitors and can also be applied in clinical settings.


Assuntos
Suor , Dispositivos Eletrônicos Vestíveis , Humanos , Temperatura Corporal , Cloretos , Pele
4.
Commun Biol ; 6(1): 157, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36750754

RESUMO

Melatonin protects against Cadmium (Cd)-induced toxicity, a ubiquitous environmental toxicant that causes adverse health effects by increasing reactive oxygen species (ROS) production and mitochondrial dysfunction. However, the underlying mechanism remains unclear. Here, we demonstrate that Cd exposure reduces the levels of mitochondrially-localized signal transducer and activator of transcription 3 (mitoSTAT3) using human prostate stromal cells and mouse embryonic fibroblasts. Melatonin enhances mitoSTAT3 abundance following Cd exposure, which is required to attenuate ROS damage, mitochondrial dysfunction, and cell death caused by Cd exposure. Moreover, melatonin increases mitochondrial levels of GRIM-19, an electron transport chain component that mediates STAT3 import into mitochondria, which are downregulated by Cd. In vivo, melatonin reverses the reduced size of mouse prostate tissue and levels of mitoSTAT3 and GRIM-19 induced by Cd exposure. Together, these data suggest that melatonin regulates mitoSTAT3 function to prevent Cd-induced cytotoxicity and could preserve mitochondrial function during Cd-induced stress.


Assuntos
Cádmio , Melatonina , Masculino , Humanos , Animais , Camundongos , Cádmio/metabolismo , Melatonina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Próstata , Fibroblastos/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo
5.
Anal Chim Acta ; 1238: 340644, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36464435

RESUMO

Prostate cancer (PCa) is the most prevalent cancer worldwide, with a high mortality rate. The early and accurate detection of PCa is critical in reducing mortality and saving lives. Timely diagnosis can improve the chances of successful treatment using advanced technologies. In recent years, nanomaterial-based electrochemical sensing strategies have been adopted in clinical diagnosis, as they allow sensitive early-biomarker detections to be converged with a cost-effective electronic readout system. Herein, we present a flexible electrochemical immunosensor platform for detecting interleukin-6 (IL-6) based on an Au-integrated flexible carbon fiber (Au/CF) electrode prepared via electrodeposition and chemically modified to capture IL-6 antibodies. Several techniques are used to analyze the prepared Au/CF composite electrodes to confirm their morphology, structure, and elemental composition. Under optimum conditions, the fabricated immunosensor exhibits a wide linear dynamic ranging from 1 fg/mL to 1 µg/mL and a low detection limit of 0.056 fg/mL, with a sensitivity of 62.17 µA/(fg mL-1). The proposed fiber-based immunosensor is used to quantify the concentration of IL-6 in serum samples from clinical PCa patients (T3b and T4 stages), and the results are validated using the commercial Meso Scale Diagnostics (MSD) V-Plex method. The acceptable results yielded by the proposed immunosensor indicate that it can serve as a new platform to realize highly sensitive and cost-effective diagnostic strategies for the early diagnosis of PCa.


Assuntos
Técnicas Biossensoriais , Interleucina-6 , Masculino , Humanos , Fibra de Carbono , Imunoensaio , Anticorpos
6.
Lab Chip ; 23(2): 229-238, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36484274

RESUMO

Antibiotic resistance threatens human health worldwide. Patients infected with antibiotic-resistant bacteria require appropriate antibiotic prescriptions based on a rapid antibiotic susceptibility test (AST). Various rapid AST methods have been developed to replace the conventional AST method, which requires a long testing time. However, in most cases, these methods require a high density of bacterial samples, which leads to an additional incubation or concentration process. In this study, we introduce a rapid AST platform that allows the use of low-density bacterial samples by concentrating bacterial cells and performing AST on a single microfluidic chip. In addition, the outlet-free loading process enables the platform to load the sample and concentrate bacteria into a small field of view for single-cell detection. Using this method, rapid AST determined antibiotic resistance in three hours from a standard strain of 103 colony-forming unit (CFU) per ml bacterial concentration. This technique can be used for the cell-based drug testing of various low-concentration bacterial samples.


Assuntos
Antibacterianos , Bactérias , Humanos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Microfluídica/métodos , Fatores de Tempo
7.
Pharmaceuticals (Basel) ; 15(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36558939

RESUMO

The development of efficient point-of-care (POC) diagnostic tools for detecting infectious diseases caused by destructive pathogens plays an important role in clinical and environmental monitoring. Nevertheless, evolving complex and inconsistent antibiotic-resistant species mire their drug efficacy. In this regard, substantial effort has been expended to develop electrochemical sensors, which have gained significant interest for advancing POC testing with rapid and accurate detection of resistant bacteria at a low cost compared to conventional phenotype methods. This review concentrates on the recent developments in electrochemical sensing techniques that have been applied to assess the diverse latent antibiotic resistances of pathogenic bacteria. It deliberates the prominence of biorecognition probes and tailor-made nanomaterials used in electrochemical antibiotic susceptibility testing (AST). In addition, the bimodal functional efficacy of nanomaterials that can serve as potential transducer electrodes and the antimicrobial agent was investigated to meet the current requirements in designing sensor module development. In the final section, we discuss the challenges with contemporary AST sensor techniques and extend the key ideas to meet the demands of the next POC electrochemical sensors and antibiotic design modules in the healthcare sector.

8.
Mol Cells ; 45(8): 537-549, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35950455

RESUMO

Preproenkephalin (PPE) is a precursor molecule for multiple endogenous opioid peptides Leu-enkephalin (ENK) and Met-ENK, which are involved in a wide variety of modulatory functions in the nervous system. Despite the functional importance of ENK in the brain, the effect of brain-derived factor(s) on PPE expression is unknown. We report the dual effect of neural epidermal growth factor (EGF)-likelike 2 (NELL2) on PPE gene expression. In cultured NIH3T3 cells, transfection of NELL2 expression vectors induced an inhibition of PPE transcription intracellularly, in parallel with downregulation of protein kinase C signaling pathways and extracellular signal-regulated kinase. Interestingly, these phenomena were reversed when synthetic NELL2 was administered extracellularly. The in vivo disruption of NELL2 synthesis resulted in an increase in PPE mRNA level in the rat brain, suggesting that the inhibitory action of intracellular NELL2 predominates the activation effect of extracellular NELL2 on PPE gene expression in the brain. Biochemical and molecular studies with mutant NELL2 structures further demonstrated the critical role of EGF-like repeat domains in NELL2 for regulation of PPE transcription. These are the first results to reveal the spatio-specific role of NELL2 in the homeostatic regulation of PPE gene expression.


Assuntos
Fator de Crescimento Epidérmico , Proteínas do Tecido Nervoso , Animais , Encefalinas , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/farmacologia , Expressão Gênica , Camundongos , Células NIH 3T3 , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Precursores de Proteínas , Ratos
9.
Molecules ; 27(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36014455

RESUMO

Cadmium (Cd), a harmful heavy metal, can lead to various pulmonary diseases, including chronic obstructive pulmonary disease (COPD), by inducing cytotoxicity and disturbing redox homeostasis. The aim of the present study was to investigate Cd-mediated cytotoxicity using human lung fibroblasts and the therapeutic potential of 3,3'-diindolylmethane (DIM). Cadmium significantly reduced the cell viability of human embryonic lung (HEL299) cells accompanied by enhanced oxidative stress as evidenced by the increased expression of autophagy-related proteins such as LC3B and p62. However, treatment with DIM significantly suppressed autophagic cell death in Cd-induced HEL299 fibroblasts. In addition, DIM induced antioxidant enzyme activity and decreased intracellular reactive oxygen species (ROS) levels in Cd-damaged HEL299 cells. This study suggests that DIM effectively suppressed Cd-induced lung fibroblast cell death through the upregulation of antioxidant systems and represents a potential agent for the prevention of various diseases related to Cd exposure.


Assuntos
Morte Celular Autofágica , Cádmio , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Autofagia , Cádmio/toxicidade , Fibroblastos/metabolismo , Humanos , Indóis , Pulmão/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
10.
Biomol Ther (Seoul) ; 30(4): 360-367, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35264466

RESUMO

Tropomyosin receptor kinase A (TrkA) protein is a receptor tyrosine kinase encoded by the NTRK1 gene. TrkA signaling mediates the proliferation, differentiation, and survival of neurons and other cells following stimulation by its ligand, the nerve growth factor. Chromosomal rearrangements of the NTRK1 gene result in the generation of TrkA fusion protein, which is known to cause deregulation of TrkA signaling. Targeting TrkA activity represents a promising strategy for the treatment of cancers that harbor the TrkA fusion protein. In this study, we evaluated the TrkA-inhibitory activity of the benzoxazole compound KRC-108. KRC-108 inhibited TrkA activity in an in vitro kinase assay, and suppressed the growth of KM12C colon cancer cells harboring an NTRK1 gene fusion. KRC-108 treatment induced cell cycle arrest, apoptotic cell death, and autophagy. KRC-108 suppressed the phosphorylation of downstream signaling molecules of TrkA, including Akt, phospholipase Cγ, and ERK1/2. Furthermore, KRC-108 exhibited anti-tumor activity in vivo in a KM12C cell xenograft model. These results indicate that KRC-108 may be a promising therapeutic agent for Trk fusion-positive cancers.

12.
Molecules ; 26(20)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34684681

RESUMO

Bisphenol A (BPA) is a typical environmental endocrine disruptor that exhibits estrogen-mimicking, hormone-like properties and can cause the collapse of bone homeostasis by an imbalance between osteoblasts and osteoclasts. Various BPA substitutes, structurally similar to BPA, have been used to manufacture 'BPA-free' products; however, the regulatory role of BPA alternatives in osteoclast differentiation still remains unelucidated. This study aimed to investigate the effects of these chemicals on osteoclast differentiation using the mouse osteoclast precursor cell line RAW 264.7. Results confirmed that both BPA and its alternatives, bisphenol F and tetramethyl bisphenol F (TMBPF), were nontoxic to RAW 264.7 cells. In particular, tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cell staining and activity calculation assays revealed that TMBPF enhanced osteoclast differentiation upon stimulation of the receptor activator of nuclear factor-kappa B ligand (RANKL). Additionally, TMBPF activated the mRNA expression of osteoclast-related target genes, such as the nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CtsK). Western blotting analysis indicated activation of the mitogen-activated protein kinase signaling pathway, including phosphorylation of c-Jun N-terminal kinase and p38. Together, the results suggest that TMBPF enhances osteoclast differentiation, and it is critical for bone homeostasis and skeletal health.


Assuntos
Compostos Benzidrílicos/farmacologia , Estrogênios não Esteroides/farmacologia , Osteoblastos/efeitos dos fármacos , Fenóis/farmacologia , Animais , Reabsorção Óssea , Diferenciação Celular/efeitos dos fármacos , Estrogênios/análogos & derivados , Estrogênios/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
13.
ACS Nano ; 15(10): 15730-15740, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34585584

RESUMO

The recent emergence of highly contagious respiratory disease and the underlying issues of worldwide air pollution jointly heighten the importance of the personal respirator. However, the incongruence between the dynamic environment and nonadaptive respirators imposes physiological and psychological adverse effects, which hinder the public dissemination of respirators. To address this issue, we introduce adaptive respiratory protection based on a dynamic air filter (DAF) driven by machine learning (ML) algorithms. The stretchable elastomer fiber membrane of the DAF affords immediate adjustment of filtration characteristics through active rescaling of the micropores by simple pneumatic control, enabling seamless and constructive transition of filtration characteristics. The resultant DAF-respirator (DAF-R), made possible by ML algorithms, successfully demonstrates real-time predictive adapting maneuvers, enabling personalizable and continuously optimized respiratory protection under changing circumstances.


Assuntos
Filtros de Ar , Nanofibras , Exposição Ocupacional , Filtração
14.
Redox Biol ; 47: 102144, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34562873

RESUMO

Although effective drugs have been developed, including 5-fluorouracil (5-FU), advanced colorectal cancer (CRC) shows low therapeutic sensitivity resulting from the development of 5-FU resistance. Thymidylate synthase (TS) is a target protein of 5-FU, and elevated TS lowers the 5-FU sensitivity of CRC cells. Here, we tested the efficacy of several candidate phytochemicals against human CRC-derived HCT116 cells expressing wild-type tumor suppressor protein P53 and HT29 cells expressing mutant P53. Among them, we found that apigenin enhanced the inhibitory effect of 5-FU on cell viability. In addition, apigenin inhibited the upregulation of TS induced by 5-FU. Apigenin also potentiated 5-FU-induced apoptosis of HCT116 cells and enhanced cell cycle disruption. Furthermore, apigenin increased reactive oxygen species production, intracellular and intramitochondrial Ca2+ concentrations, and mitochondrial membrane potential upon cotreatment with 5-FU. Knockdown of forkhead box protein M, a transcription factor modulating 5-FU sensitivity, enhanced the potentiation of apoptosis by apigenin in HCT116 cells. Moreover, apigenin suppressed TS expression and inhibited the viability of 5-FU-resistant HCT116 cells. Therefore, apigenin may improve the therapeutic efficacy of 5-FU against CRC by suppressing TS, but apoptosis induction is mainly dependent on functional P53.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Colorretais , Fluoruracila , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apigenina/farmacologia , Apoptose , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Fluoruracila/farmacologia , Humanos , Timidilato Sintase/genética
15.
Biosensors (Basel) ; 11(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34436085

RESUMO

Since the discovery of antibiotics, the emergence of antibiotic resistance has become a global issue that is threatening society. In the era of antibiotic resistance, finding the proper antibiotics through antibiotic susceptibility testing (AST) is crucial in clinical settings. However, the current clinical process of AST based on the broth microdilution test has limitations on scalability to expand the number of antibiotics that are tested with various concentrations. Here, we used color-coded droplets to expand the multiplexing of AST regarding the kind and concentration of antibiotics. Color type and density differentiate the kind of antibiotics and concentration, respectively. Microscopic images of a large view field contain numbers of droplets with different testing conditions. Image processing analysis detects each droplet, decodes color codes, and measures the bacterial growth in the droplet. Testing E. coli ATCC 25922 with ampicillin, gentamicin, and tetracycline shows that the system can provide a robust and scalable platform for multiplexed AST. Furthermore, the system can be applied to various drug testing systems, which require several different testing conditions.


Assuntos
Testes de Sensibilidade Microbiana , Ampicilina , Antibacterianos , Técnicas Biossensoriais , Resistência Microbiana a Medicamentos , Desenho de Equipamento , Escherichia coli , Processamento de Imagem Assistida por Computador , Técnicas Analíticas Microfluídicas , Tetraciclina , Fatores de Tempo
16.
Nat Commun ; 12(1): 5008, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429436

RESUMO

Capabilities for continuous monitoring of pressures and temperatures at critical skin interfaces can help to guide care strategies that minimize the potential for pressure injuries in hospitalized patients or in individuals confined to the bed. This paper introduces a soft, skin-mountable class of sensor system for this purpose. The design includes a pressure-responsive element based on membrane deflection and a battery-free, wireless mode of operation capable of multi-site measurements at strategic locations across the body. Such devices yield continuous, simultaneous readings of pressure and temperature in a sequential readout scheme from a pair of primary antennas mounted under the bedding and connected to a wireless reader and a multiplexer located at the bedside. Experimental evaluation of the sensor and the complete system includes benchtop measurements and numerical simulations of the key features. Clinical trials involving two hemiplegic patients and a tetraplegic patient demonstrate the feasibility, functionality and long-term stability of this technology in operating hospital settings.


Assuntos
Técnicas Biossensoriais , Fontes de Energia Elétrica , Úlcera por Pressão , Pressão , Temperatura , Tecnologia sem Fio , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Desenho de Equipamento , Monitorização Fisiológica , Pele , Termografia/instrumentação , Termografia/métodos
17.
Sci Transl Med ; 13(587)2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33790027

RESUMO

The concentration of chloride in sweat remains the most robust biomarker for confirmatory diagnosis of cystic fibrosis (CF), a common life-shortening genetic disorder. Early diagnosis via quantitative assessment of sweat chloride allows prompt initiation of care and is critically important to extend life expectancy and improve quality of life. The collection and analysis of sweat using conventional wrist-strapped devices and iontophoresis can be cumbersome, particularly for infants with fragile skin, who often have insufficient sweat production. Here, we introduce a soft, epidermal microfluidic device ("sweat sticker") designed for the simple and rapid collection and analysis of sweat. Intimate, conformal coupling with the skin supports nearly perfect efficiency in sweat collection without leakage. Real-time image analysis of chloride reagents allows for quantitative assessment of chloride concentrations using a smartphone camera, without requiring extraction of sweat or external analysis. Clinical validation studies involving patients with CF and healthy subjects, across a spectrum of age groups, support clinical equivalence compared to existing device platforms in terms of accuracy and demonstrate meaningful reductions in rates of leakage. The wearable microfluidic technologies and smartphone-based analytics reported here establish the foundation for diagnosis of CF outside of clinical settings.


Assuntos
Fibrose Cística , Suor , Cloretos , Fibrose Cística/diagnóstico , Fibrose Cística/terapia , Humanos , Lactente , Qualidade de Vida , Smartphone
18.
Antibiotics (Basel) ; 10(3)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805824

RESUMO

Antimicrobial resistance has become a major problem in public health and clinical environments. Against this background, antibiotic susceptibility testing (AST) has become necessary to cure diseases in an appropriate and timely manner as it indicates the necessary concentration of antibiotics. Recently, microfluidic based rapid AST methods using microscopic analysis have been shown to reduce the time needed for the determination of the proper antibiotics. However, owing to the inoculum effect, the accurate measurement of the minimal inhibitory concentration (MIC) is difficult. We tested four standard bacteria: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecalis, against five different antibiotics: piperacillin, cefotaxime, amikacin, levofloxacin, and ampicillin. The results showed that overall, the microfluidic system has a similar inoculum effect compared to the conventional AST method. However, due to the different testing conditions and determination protocols of the growth of the microfluidic based rapid AST, a few results are not identical to the conventional methods using optical density. This result suggests that microfluidic based rapid AST methods require further research on the inoculum effect for practical use in hospitals and can then be used for effective antibiotic prescriptions.

19.
J Biomed Opt ; 26(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33624459

RESUMO

SIGNIFICANCE: Dry or moist skin-contact thermal stimulation for vein puncture (VP) and vein cannulation (VC) may not be feasible for sensitive skin. For a damaged, burned, or dark skin, near-infrared (NIR) imaging is preferred to visualize a vein. Postprocessing of NIR images is always required because the skin is a reflective material and veins need segmentation for quantitative analysis. AIM: Our pilot study aims to observe the effect of noncontact local heating on the superficial metacarpal veins in the dorsal surface of the hand and to visualize vein dynamics using an NIR imaging system. APPROACH: Our experiment consists of studies A and B at two ambient temperatures, 19°C and 25°C. A simple reflection-based NIR imaging system was installed to acquire sequential vein images for 5 min before and after applying 10 min of radiant thermal stimulation. To measure the vein diameter (VD), we trained a convolutional neural network (CNN) on sequential raw images to predict vein-segmentation masks as output images. Later these masked images were postprocessed for the VD measurements. RESULTS: The average VD was significantly increased after thermal stimulation in study A. The maximum increments in VD were 39.3% and 9.19%, 1 min after thermal stimulation in studies A and B, respectively. Both the VD and skin temperature (Tskin) follow negative exponentials in time, and the VD is proportional to Tskin. A multiple linear-regression model was made to predict the final VD. A significant difference was observed in the change of the VD. CONCLUSIONS: NIR imaging with CNN can be used for quantitative analyses of vein dynamics. This finding can be further extended to develop real-time, image-guided medical devices by integrating them with a radiant heater and to assist medical practitioners in achieving high success rates for VP or VC.


Assuntos
Diagnóstico por Imagem , Veias , Redes Neurais de Computação , Projetos Piloto , Temperatura , Veias/diagnóstico por imagem
20.
Pharmaceuticals (Basel) ; 14(1)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419162

RESUMO

Rearranged during transfection (RET), a receptor tyrosine kinase, is activated by glial cell line-derived neurotrophic factor family ligands. Chromosomal rearrangement or point mutations in RET are observed in patients with papillary thyroid and medullary thyroid carcinomas. Oncogenic alteration of RET results in constitutive activation of RET activity. Therefore, inhibiting RET activity has become a target in thyroid cancer therapy. Here, the anti-tumor activity of a novel RET inhibitor was characterized in medullary thyroid carcinoma cells. The indirubin derivative LDD-2633 was tested for RET kinase inhibitory activity. In vitro, LDD-2633 showed potent inhibition of RET kinase activity, with an IC50 of 4.42 nM. The growth of TT thyroid carcinoma cells harboring an RET mutation was suppressed by LDD-2633 treatment via the proliferation suppression and the induction of apoptosis. The effects of LDD-2633 on the RET signaling pathway were examined; LDD-2633 inhibited the phosphorylation of the RET protein and the downstream molecules Shc and ERK1/2. Oral administration of 20 or 40 mg/kg of LDD-2633 induced dose-dependent suppression of TT cell xenograft tumor growth. The in vivo and in vitro experimental results supported the potential use of LDD-2633 as an anticancer drug for thyroid cancers.

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