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1.
Nanomicro Lett ; 16(1): 238, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976105

RESUMEN

The emergence of the Internet-of-Things is anticipated to create a vast market for what are known as smart edge devices, opening numerous opportunities across countless domains, including personalized healthcare and advanced robotics. Leveraging 3D integration, edge devices can achieve unprecedented miniaturization while simultaneously boosting processing power and minimizing energy consumption. Here, we demonstrate a back-end-of-line compatible optoelectronic synapse with a transfer learning method on health care applications, including electroencephalogram (EEG)-based seizure prediction, electromyography (EMG)-based gesture recognition, and electrocardiogram (ECG)-based arrhythmia detection. With experiments on three biomedical datasets, we observe the classification accuracy improvement for the pretrained model with 2.93% on EEG, 4.90% on ECG, and 7.92% on EMG, respectively. The optical programming property of the device enables an ultra-low power (2.8 × 10-13 J) fine-tuning process and offers solutions for patient-specific issues in edge computing scenarios. Moreover, the device exhibits impressive light-sensitive characteristics that enable a range of light-triggered synaptic functions, making it promising for neuromorphic vision application. To display the benefits of these intricate synaptic properties, a 5 × 5 optoelectronic synapse array is developed, effectively simulating human visual perception and memory functions. The proposed flexible optoelectronic synapse holds immense potential for advancing the fields of neuromorphic physiological signal processing and artificial visual systems in wearable applications.

2.
Sensors (Basel) ; 23(21)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37960581

RESUMEN

A hypoglossal nerve stimulator (HGNS) is an invasive device that is used to treat obstructive sleep apnea (OSA) through electrical stimulation. The conventional implantable HGNS device consists of a stimuli generator, a breathing sensor, and electrodes connected to the hypoglossal nerve via leads. However, this implant is bulky and causes significant trauma. In this paper, we propose a minimally invasive HGNS based on an electrocardiogram (ECG) sensor and wireless power transfer (WPT), consisting of a wearable breathing monitor and an implantable stimulator. The breathing external monitor utilizes an ECG sensor to identify abnormal breathing patterns associated with OSA with 88.68% accuracy, achieved through the utilization of a convolutional neural network (CNN) algorithm. With a skin thickness of 5 mm and a receiving coil diameter of 9 mm, the power conversion efficiency was measured as 31.8%. The implantable device, on the other hand, is composed of a front-end CMOS power management module (PMM), a binary-phase-shift-keying (BPSK)-based data demodulator, and a bipolar biphasic current stimuli generator. The PMM, with a silicon area of 0.06 mm2 (excluding PADs), demonstrated a power conversion efficiency of 77.5% when operating at a receiving frequency of 2 MHz. Furthermore, it offers three-voltage options (1.2 V, 1.8 V, and 3.1 V). Within the data receiver component, a low-power BPSK demodulator was ingeniously incorporated, consuming only 42 µW when supplied with a voltage of 0.7 V. The performance was achieved through the implementation of the self-biased phase-locked-loop (PLL) technique. The stimuli generator delivers biphasic constant currents, providing a 5 bit programmable range spanning from 0 to 2.4 mA. The functionality of the proposed ECG- and WPT-based HGNS was validated, representing a highly promising solution for the effective management of OSA, all while minimizing the trauma and space requirements.


Asunto(s)
Terapia por Estimulación Eléctrica , Apnea Obstructiva del Sueño , Humanos , Terapia por Estimulación Eléctrica/métodos , Nervio Hipogloso , Apnea Obstructiva del Sueño/terapia , Prótesis e Implantes , Electrocardiografía
3.
Elife ; 122023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37888961

RESUMEN

Background: The overactivation of NF-κB signaling is a key hallmark for the pathogenesis of extranodal natural killer/T cell lymphoma (ENKTL), a very aggressive subtype of non-Hodgkin's lymphoma yet with rather limited control strategies. Previously, we found that the dysregulated exportin-1 (also known as CRM1) is mainly responsible for tumor cells to evade apoptosis and promote tumor-associated pathways such as NF-κB signaling. Methods: Herein we reported the discovery and biological evaluation of a potent small molecule CRM1 inhibitor, LFS-1107. We validated that CRM1 is a major cellular target of LFS-1107 by biolayer interferometry assay (BLI) and the knockdown of CRM1 conferred tumor cells with resistance to LFS-1107. Results: We found that LFS-1107 can strongly suppresses the growth of ENKTL cells at low-range nanomolar concentration yet with minimal effects on human platelets and healthy peripheral blood mononuclear cells. Treatment of ENKTL cells with LFS-1107 resulted in the nuclear retention of IkBα and consequent strong suppression of NF-κB transcriptional activities, NF-κB target genes downregulation and attenuated tumor cell growth and proliferation. Furthermore, LFS-1107 exhibited potent activities when administered to immunodeficient mice engrafted with human ENKTL cells. Conclusions: Therefore, LFS-1107 holds great promise for the treatment of ENKTL and may warrant translation for use in clinical trials. Funding: Yang's laboratory was supported by the National Natural Science Foundation of China (Grant: 81874301), the Fundamental Research Funds for Central University (Grant: DUT22YG122) and the Key Research project of 'be Recruited and be in Command' in Liaoning Province (Personal Target Discovery for Metabolic Diseases).


Asunto(s)
Linfoma Extranodal de Células NK-T , Neoplasias , Humanos , Animales , Ratones , FN-kappa B/metabolismo , Linfoma Extranodal de Células NK-T/tratamiento farmacológico , Linfoma Extranodal de Células NK-T/genética , Linfoma Extranodal de Células NK-T/patología , Leucocitos Mononucleares/metabolismo , Transducción de Señal , Neoplasias/metabolismo
4.
Front Public Health ; 11: 1210800, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37383271

RESUMEN

Background: Specific underlying diseases were reported to be associated with severe COVID-19 outcomes, but little is known about their combined associations. The study was aimed to assess the relations of number of and specific underlying diseases to COVID-19, severe symptoms, loss of smell, and loss of taste. Methods: A total of 28,204 adult participants in the National Health Interview Survey 2021 were included. Underlying diseases (including cardiovascular diseases, cancer, endocrine diseases, respiratory diseases, neuropsychiatric diseases, liver and kidney diseases, fatigue syndrome, and sensory impairments), the history of COVID-19, and its symptoms were self-reported by structured questionnaires. Multivariable logistic regression models were used to assess the combined relation of total number of underlying diseases to COVID-19 and its symptoms, while mutually adjusted logistic models were used to examine their independent associations. Results: Among the 28,204 participants (mean ± standard deviation: 48.2 ± 18.5 years), each additional underlying disease was related to 33, 20, 37, and 39% higher odds of COVID-19 (odds ratio [OR]: 1.33, 95% confidence interval [CI]: 1.29-1.37), severe symptoms (OR: 1.20, 95% CI: 1.12-1.29), loss of smell (OR: 1.37, 95% CI: 1.29-1.46), and loss of taste (OR: 1.39, 95% CI: 1.31-1.49). In addition, independent associations of sensory impairments with COVID-19 (OR: 3.73, 95% CI: 3.44-4.05), severe symptoms (OR: 1.37, 95% CI: 1.13-1.67), loss of smell (OR: 8.17, 95% CI: 6.86-9.76), and loss of taste (OR: 6.13, 95% CI: 5.19-7.25), cardiovascular diseases with COVID-19 (OR: 1.13, 95% CI: 1.03-1.24), neuropsychiatric diseases with severe symptoms (OR: 1.41, 95% CI: 1.15-1.74), and endocrine diseases with loss of taste (OR: 1.28, 95% CI: 1.05-1.56) were observed. Conclusion: A larger number of underlying diseases were related to higher odds of COVID-19, severe symptoms, loss of smell, and loss of taste in a dose-response manner. Specific underlying diseases might be individually associated with COVID-19 and its symptoms.


Asunto(s)
COVID-19 , Comorbilidad , Humanos , Adulto , Estudios Transversales , COVID-19/epidemiología , Persona de Mediana Edad , Encuestas y Cuestionarios , Modelos Logísticos , Análisis Multivariante , Estados Unidos , Anciano , Evaluación de Síntomas , Anosmia/virología , Ageusia/virología
5.
Adv Mater ; 35(28): e2300446, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37192130

RESUMEN

Being renowned for operating with visible-light pulses and electrical signals, optoelectronic memristive synaptic devices have excellent potential for neuromorphic computing systems and artificial visual information processing. Here, a flexible back-end-of-line-compatible optoelectronic memristor based on a solution-processable black phosphorus/HfOx bilayer with excellent synaptic features, toward biomimetic retinas is presented. The device shows highly stable synaptic features such as long-term potentiation (LTP) and long-term depression (LTD) for repetitive 1000 epochs, having 400 conductance pulses, each. The device presents advanced synaptic features in terms of long-term memory (LTM)/short term memory (STM), as well as learning-forgetting-relearning when visible light is induced on it. These advanced synaptic features can improve the information processing abilities for neuromorphic applications. Interestingly, the STM can be converted into LTM by adjusting the intensity of light and illumination time. Using the light-induced characteristics of the device, a 6 × 6 synaptic array is developed to exhibit possible use in artificial visual perception. Moreover, the devices are flexed using a silicon back-etching process. The resulting flexible devices demonstrate stable synaptic features when bent down to 1 cm radius. These multifunctional features in a single memristive cell make it highly suitable for optoelectronic memory storage, neuromorphic computing, and artificial visual perception applications.


Asunto(s)
Luz , Percepción Visual , Cognición , Fósforo , Sinapsis
6.
Light Sci Appl ; 12(1): 109, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147334

RESUMEN

Optoelectronic devices are advantageous in in-memory light sensing for visual information processing, recognition, and storage in an energy-efficient manner. Recently, in-memory light sensors have been proposed to improve the energy, area, and time efficiencies of neuromorphic computing systems. This study is primarily focused on the development of a single sensing-storage-processing node based on a two-terminal solution-processable MoS2 metal-oxide-semiconductor (MOS) charge-trapping memory structure-the basic structure for charge-coupled devices (CCD)-and showing its suitability for in-memory light sensing and artificial visual perception. The memory window of the device increased from 2.8 V to more than 6 V when the device was irradiated with optical lights of different wavelengths during the program operation. Furthermore, the charge retention capability of the device at a high temperature (100 °C) was enhanced from 36 to 64% when exposed to a light wavelength of 400 nm. The larger shift in the threshold voltage with an increasing operating voltage confirmed that more charges were trapped at the Al2O3/MoS2 interface and in the MoS2 layer. A small convolutional neural network was proposed to measure the optical sensing and electrical programming abilities of the device. The array simulation received optical images transmitted using a blue light wavelength and performed inference computation to process and recognize the images with 91% accuracy. This study is a significant step toward the development of optoelectronic MOS memory devices for neuromorphic visual perception, adaptive parallel processing networks for in-memory light sensing, and smart CCD cameras with artificial visual perception capabilities.

7.
J Nanobiotechnology ; 20(1): 240, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35606848

RESUMEN

BACKGROUND: Postoperative chemotherapy for gastric cancer often causes multidrug resistance (MDR), which has serious consequences for therapeutic effects. Individualized treatment based on accurate monitoring of MDR will greatly improve patient survival. RESULTS: In this article, a self-enhanced Mn3O4 nanoplatform (MPG NPs) was established, which can react with glutathione to produce Mn2+ to enhance T1-weighted magnetic resonance imaging (MRI) and mediate in vivo real-time MDR monitoring. In vitro MRI results showed that MRI signals could be enhanced in the presence of hydrogen peroxide and glutathione and at acidic pH. In vivo MRI results indicated that MPG NPs could specifically target MDR cells, thereby realizing real-time monitoring of MDR in gastric cancer. Furthermore, MPG NPs have good chemodynamic activity, which can convert the endogenous hydrogen peroxide of tumor cells into highly toxic hydroxyl radical through Fenton-like reaction at acidic pH to play the role of chemodynamic therapy. In addition, Mn3O4 can significantly enhance the chemodynamic therapy effect because of its good photothermal conversion effect. Furthermore, in situ photothermal/chemodynamic synergistic therapy obtained remarkable results, the tumors of the mice in the synergistic therapy group gradually became smaller or even disappeared. CONCLUSIONS: MPG NPs have good biocompatibility, providing a good nanoplatform for real-time monitoring and precise diagnosis and treatment of MDR in gastric cancer.


Asunto(s)
Nanopartículas , Neoplasias , Neoplasias Gástricas , Animales , Línea Celular Tumoral , Resistencia a Medicamentos , Glutatión , Humanos , Peróxido de Hidrógeno , Ratones , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias Gástricas/tratamiento farmacológico , Microambiente Tumoral
8.
ACS Appl Mater Interfaces ; 14(5): 6387-6403, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35077131

RESUMEN

Hypoxia is a well-known feature of malignant solid tumors. To explain the misinterpretation of tumor hypoxia variation during chemotherapy, we developed a DNA origami-based theranostic nanoplatform with an intercalated anticancer anthraquinone as both the chemotherapeutic drug and the photoacoustic contrast agent. The size distribution of the DNA origami nanostructure is 44.5 ± 2.3 nm, whereas the encapsulation efficiency of the drug is 90.7 ± 1.0%, and the drug loading content is 92.2 ± 0.1%. The controlled cumulative release rates were measured in vitro, showing an acidic environment induced rapid drug release. The values of free energy of binding between the drugs and the DNA double helix were calculated through molecular simulations. The cell viability assay was used to characterize cytotoxicity, and fluorescence confocal cell imaging illustrates the biodistribution of the probe in vitro. Photoacoustic and fluorescence imaging were used to indicate drug delivery, release, and biodistribution to predict the drug's chemotherapeutic effect in vivo, whereas the photoacoustic signals were compared with those of deoxygenated/oxygenated hemoglobin to represent the tissue hypoxia/normoxia maps during the chemotherapeutic process and indicate alleviated tumor hypoxia. Staining of tissue sections taken from organs and tumors was used to verify the results of photoacoustic imaging. Our results suggest that photoacoustic imaging can visualize this DNA origami-based theranostic nanoplatform and reveal the mechanisms of chemotherapy on tumor hypoxia.


Asunto(s)
Antraquinonas/química , ADN/química , Nanoestructuras/química , Hipoxia Tumoral/efectos de los fármacos , Animales , Antraquinonas/metabolismo , Antraquinonas/farmacología , Antraquinonas/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Portadores de Fármacos/química , Femenino , Hemólisis/efectos de los fármacos , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Ratones , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Imagen Óptica , Ratas , Ratas Sprague-Dawley , Distribución Tisular
9.
Nanotechnology ; 32(16): 165703, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33429376

RESUMEN

Chemotherapy is one of conventional treatment methods for breast cancer, but drug toxicity and side effects have severely limited its clinical applications. Photothermal therapy has emerged as a promising method that, upon combination with chemotherapy, can better treat breast cancer. In this context, a biodegradable mesoporous silica nanoparticle (bMSN NPs) system was developed for loading doxorubicin (DOX) and IR780, to be potentially applied in the treatment of breast cancer. IR780 is encapsulated in the pores of bMSN NPs by hydrophobic adsorption, while DOX is adsorbed on the surface of the bMSN NPs by hyaluronic acid electrostatically, to form the bMID NPs. Transmission electron microscopy, fluorescence spectrum and UV absorption spectrum are used to prove the successful encapsulation of IR780 and the loading of DOX. In vitro experiments have shown bMID NPs present an excellent therapeutic effect on breast cancer cells. In vivo fluorescence imaging results have indicated that bMID NPs can accumulate in tumor sites gradually and achieve in vivo long-term circulation and continuous drug release. Furthermore, bMID NPs have provided obvious antitumor effects in breast cancer mouse models, thus evolving as an efficient platform for breast cancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Materiales Biocompatibles/química , Neoplasias de la Mama/terapia , Ácido Hialurónico/química , Hipertermia Inducida , Nanocompuestos/química , Fototerapia , Dióxido de Silicio/química , Animales , Muerte Celular/efectos de los fármacos , Endocitosis , Femenino , Humanos , Células MCF-7 , Ratones Desnudos , Nanopartículas/química , Nanopartículas/ultraestructura , Porosidad , Electricidad Estática , Distribución Tisular , Pruebas de Toxicidad Aguda , Ensayo de Tumor de Célula Madre
10.
Curr Med Chem ; 28(3): 496-513, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31894739

RESUMEN

Quantum Dots (QDs), whose diameters are often limited to 10 nm, have been of interest to researchers for their unique optical characteristics, which are attributed to quantum confinement. Following their early application in the electrical industry as light-emitting diode materials, semiconductor nanocrystals have continued to show great potential in clinical diagnosis and biomedical applications. The conventional physical and chemical pathways for QD syntheses typically require harsh conditions and hazardous reagents, and these products encounter non-hydrophilic problems due to organic capping ligands when they enter the physiological environment. The natural reducing abilities of living organisms, especially microbes, are then exploited to prepare QDs from available metal precursors. Low-cost and eco-friendly biosynthesis approaches have the potential for further biomedical applications which benefit from the good biocompatibility of protein-coated QDs. The surface biomass offers many binding sites to modify substances or target ligands, therefore achieving multiple functions through simple and efficient operations. Biosynthetic QDs could function as bioimaging and biolabeling agents because of their luminescence properties similar to those of chemical QDs. In addition, extensive research has been carried out on the antibacterial activity, metal ion detection and bioremediation. As a result, this review details the advanced progress of biomedical applications of biosynthesized QDs and illustrates these principles as clearly as possible.


Asunto(s)
Materiales Biocompatibles , Puntos Cuánticos , Humanos , Ligandos , Luminiscencia
11.
Front Oncol ; 10: 622, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32432038

RESUMEN

Combination chemotherapy is a routine treatment for esophageal cancer, but some shortcomings, such as drug toxicity and side effects, greatly limit the clinical application of combination therapy. To overcome these shortcomings, we have developed a mesoporous silica nanoparticle system that was used to load doxorubicin and ß-elemene. ß-elemene was encapsulated in the pore of mesoporous silica nanoparticle and doxorubicin was electrostatically adsorbed on the surface of mesoporous silica nanoparticle by hyaluronic acid to construct dual drugs synergistic nanoparticles (bMED NPs, ~77.15 nm). In vitro studies demonstrated that bMED NPs had a good treatment effect in esophageal cancer cell lines. In vivo fluorescence imaging results demonstrated that bMED NPs could accumulate in tumor sites and achieve in vivo long-term circulation and continuous drug release. In addition, bMED NPs exhibited significant antitumor effects in the esophageal cancer mouse model, which may provide a great platform for esophageal cancer chemotherapy.

12.
Anticancer Agents Med Chem ; 20(9): 1147-1156, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32106805

RESUMEN

BACKGROUND: Hepatocellular carcinoma is cancer with many new cases and the highest mortality rate. Chemotherapy is the most commonly used method for the clinical treatment of hepatocellular carcinoma. Natural products have become clinically important chemotherapeutic drugs due to their great potential for pharmacological development. Many sesquiterpene lactone compounds have been proven to have antitumor effects on hepatocellular carcinoma. OBJECTIVE: Britanin is a sesquiterpene lactone compound that can be considered for the treatment of hepatocellular carcinoma. The present study aimed to investigate the antitumor effect of britanin. METHODS: BEL 7402 and HepG2 cells were used to study the cytotoxicity and antitumor effects of britanin. Preliminary studies on the nuclear factor kappa B pathway were conducted by western blot analysis. A BEL 7402-luc subcutaneous tumor model was established for the in vivo antitumor studies of britanin. In vivo bioluminescence imaging was conducted to monitor changes in tumor size. RESULTS: The results of the cytotoxicity analysis showed that the IC50 values for britanin in BEL 7402 and HepG2 cells were 2.702µM and 6.006µM, respectively. The results of the colony formation demonstrated that the number of cells in a colony was reduced significantly after britanin treatment. And the results of transwell migration assays showed that the migration ability of tumor cells was significantly weakened after treatment with britanin. Tumor size measurements and staining results showed that tumor size was inhibited after britanin treatment. The western blot analysis results showed the inhibition of p65 protein expression and reduced the ratio of Bcl-2/Bax after treatment. CONCLUSION: A series of in vitro and in vivo experiments demonstrated that britanin had good antitumor effects and provided an option for hepatocellular carcinoma treatment.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Inula/química , Lactonas/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Imagen Óptica , Sesquiterpenos/farmacología , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Lactonas/química , Lactonas/aislamiento & purificación , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Desnudos , Estructura Molecular , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Relación Estructura-Actividad , Factores de Tiempo , Células Tumorales Cultivadas
13.
Nanomedicine ; 19: 136-144, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31048083

RESUMEN

Fluorescent probes conjugated to peptide or antibody directing groups, which exhibit high signal to background ratios, have been widely used to image tumors and monitor their growth. A photo-triggered cycloaddition reaction between the arginine-glycine-aspartic acid -N-ɛ-acryllysine (RGD-Acrk) peptides and the tetrazole compounds bound to the surface of biodegradable mesoporous silica nanoparticles (bMSN) has been used to construct a fluorescent nanoprobe (bMSN@T2-RGD-Acrk), which showed fluorescent emission at 550 nm and could selectively image the 4T1 cells and breast cancer. This means that the bMSN@T2-RGD-Acrk nanoprobe made by photo-triggered conjugation approach is a promising fluorescent imaging agent for visualizing tumors. Thus, the photo-triggered one-spot reaction can give a stable crosslinker in a biocompatible manner for bioconjugation with nanoparticles and produce a fluorescent group that is suitable for imaging in vivo.


Asunto(s)
Luz , Neoplasias/diagnóstico por imagen , Oligopéptidos/química , Dióxido de Silicio/química , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Endocitosis/efectos de los fármacos , Humanos , Ligandos , Lisina/química , Ratones , Microscopía Fluorescente , Nanopartículas/química , Nanopartículas/toxicidad , Nanopartículas/ultraestructura , Oligopéptidos/síntesis química , Porosidad , Distribución Tisular/efectos de los fármacos , Pruebas de Toxicidad Aguda
14.
RSC Adv ; 9(44): 25318-25325, 2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-35530054

RESUMEN

Molecular imaging is a powerful tool for non-invasive visualization of tumors that plays an important role in their diagnosis and treatment. The specificity of molecular imaging probes for cancer cells is important for accurate tumor visualization, with antibody and polypeptide nanoprobe conjugates having often been used as targeting agents for tumor detection. However, many traditional chemical conjugation methods employ complex conjugation reactions that result in poor efficiency and poor bioactivity. Herein, we describe the use of photo click methodology for the rapid synthesis of nanoprobes comprised of silica nanoparticles functionalized with RGD targeting units (SiO2@T1-RGDk NPs) (∼80 nm) for in vivo prostate cancer fluorescent imaging applications. These SiO2@T1-RGDk NPs exhibit a maximum absorption wavelength of 380 nm in their UV absorption spectra with a maximum fluorescence emission wavelength of 550 nm. Confocal immunofluorescent imaging reveal that SiO2@T1-RGDk NPs exhibit excellent targeting ability for visualizing cancer cells, with in vivo fluorescence imaging intensity in a subcutaneous tumor model of prostate cancer reaching a maxima after 4 h. Biosafety assessments showed that SiO2@T1-RGDk NPs demonstrate no obvious toxicity in mice, thus demonstrated that these novel NPs may prove to be promising fluorescent imaging agents for the accurate detection and treatment of tumors.

15.
Nanomedicine ; 14(6): 1867-1877, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29733890

RESUMEN

Cancer metastasis is one of the biggest challenges in cancer treatments since it increases the likelihood that a patient will die from the disease. Therefore, the availability of techniques for the early detection and quantification of tumors is very important. We have prepared cyanine 7.5 NHS ester (Cy7.5) and folic acid (FA) conjugated biodegradable mesoporous silica nanoparticles (bMSN@Cy7.5-FA NPs) (~100 nm) for visualizing tumors in vivo. The fluorescence spectra revealed that the emission peak of bMSN@Cy7.5-FA NPs had a red-shift of 1 nm. Confocal immunofluorescent images showed that bMSN@Cy7.5-FA NPs had an excellent targeting ability for visualizing cancer cells. In vivo fluorescence imaging has been conducted using an orthotopic model for pancreatic cancer within 48 h, and the fluorescence intensity reached a maximum at a post injection time-point of 12 h, which demonstrated that the use of bMSN@Cy7.5-FA NPs provides an excellent imaging platform for tumor precision therapy in mice.


Asunto(s)
Fluorescencia , Ácido Fólico/química , Nanopartículas/administración & dosificación , Imagen Óptica/métodos , Neoplasias Pancreáticas/secundario , Dióxido de Silicio/química , Espectroscopía Infrarroja Corta , Animales , Humanos , Ratones , Nanopartículas/química , Células Tumorales Cultivadas
16.
J Med Chem ; 61(4): 1474-1482, 2018 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-29377691

RESUMEN

Given the clinical therapeutic efficacy of oral-dosed bardoxolone methyl (1) and the selective vasodilatory effect caused by inhalation of nitric oxide (NO) on pulmonary arterial hypertension (PAH) patients, a new hybrid (CDDO-NO, 2) from 1 and NO donor isosorbide 5-mononitrate (3) was designed and synthesized. This hybrid could liberate 1 and NO in the lungs of rats after trachea injection. Significantly, 2 lowered mean pulmonary artery pressure (mPAP) and right ventricular systolic pressure (RVSP), decreased right ventricular hypertrophy (RVH), and attenuated pulmonary artery medial thickness (PAMT) and vascular muscularization in monocrotaline (MCT)-induced PAH rats. Meanwhile, 2 inhibited overproliferation of perivascular cells and diminished macrophage infiltration and oxidative stress by inactivation of NOX4. In addition, 2 markedly reduced cardiac hypertrophy and fibrosis in the PAH rats. Overall, 2 exhibited potent dual activities of pulmonary vasodilation and vascular remodeling inhibition, suggesting that it may be a promising agent for PAH intervention.


Asunto(s)
Hipertensión Pulmonar/tratamiento farmacológico , Dinitrato de Isosorbide/análogos & derivados , Ácido Oleanólico/análogos & derivados , Remodelación Vascular/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Animales , Cardiomegalia/tratamiento farmacológico , Diseño de Fármacos , Fibrosis/tratamiento farmacológico , Dinitrato de Isosorbide/química , Donantes de Óxido Nítrico , Ácido Oleanólico/química , Ratas
17.
Molecules ; 22(12)2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-29231865

RESUMEN

Multifunctional manganese oxide nanoparticles (NPs) with impressive enhanced T1 contrast ability show great promise in biomedical diagnosis. Herein, we developed a dual-modality imaging agent system based on polyethylene glycol (PEG)-coated manganese oxide NPs conjugated with organic dye (Cy7.5), which functions as a fluorescence imaging (FI) agent as well as a magnetic resonance imaging (MRI) imaging agent. The formed Mn3O4@PEG-Cy7.5 NPs with the size of ~10 nm exhibit good colloidal stability in different physiological media. Serial FI and MRI studies that non-invasively assessed the bio-distribution pattern and the feasibility for in vivo dual-modality imaging-guided lymph node mapping have been investigated. In addition, histological and biochemical analyses exhibited low toxicity even at a dose of 20 mg/kg in vivo. Since Mn3O4@PEG-Cy7.5 NPs exhibited desirable properties as imaging agents and good biocompatibility, this work offers a robust, safe, and accurate diagnostic platform based on manganese oxide NPs for tumor metastasis diagnosis.


Asunto(s)
Medios de Contraste/química , Ganglios Linfáticos/metabolismo , Imagen por Resonancia Magnética/métodos , Compuestos de Manganeso/química , Nanopartículas/química , Imagen Óptica/métodos , Óxidos/química , Animales , Materiales Biocompatibles/química , Transporte Biológico , Línea Celular Tumoral , Ratones Endogámicos BALB C , Nanopartículas/toxicidad , Tamaño de la Partícula , Polietilenglicoles/química , Propiedades de Superficie , Distribución Tisular
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