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1.
Dev Neurosci ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38583418

RESUMEN

INTRODUCTION: Transcription factor EB (TFEB), a key regulator of autophagy and lysosomal biogenesis, has diverse roles in various physiological processes. Enhancing lysosomal function by TFEB activation has recently been implicated in restoring neural stem cells (NSCs) function. Overexpression of TFEB can inhibit the cell cycle of newborn cortical NSCs. It has also been found that TFEB regulates the pluripotency transcriptional network in mouse embryonic stem cells independent of autophagy lysosomal biogenesis. This study aims to explore the effects of TFEB activation on neurogenesis in vivo through transgenic mice. METHODS: We developed a GFAP-driven TFEB overexpression mouse model (TFEB GoE) by crossing the floxed TFEB overexpression mice and hGFAP-cre mice. We performed immunohistochemical and fluorescence staining on brain tissue from newborn mice to assess neurogenesis changes, employing markers such as GFAP, Nestin, Ki67, DCX, Tbr1 and Neun to trace different stages of neural development and cell proliferation. RESULTS: TFEB GoE mice exhibited premature mortality, dying at 10-20 days after birth. Immunohistochemical analysis revealed significant abnormalities, including disrupted hippocampal structure and cortical layering. Compared to control mice, TFEB GoE mice showed a marked increase in radial glial cells (RGCs) in the hippocampus and cortex, with Ki67 staining indicating these cells were predominantly in a quiescent state. This suggests that TFEB overexpression suppresses RGCs proliferation. Additionally, abnormal distributions of migrating neurons and mature neurons were observed, highlighted by DCX, Tbr1 and Neun staining, indicating a disruption in normal neurogenesis. CONCLUSION: This study, using transgenic animals in vivo, revealed that GFAP-driven TFEB overexpression leads to abnormal neural layering in the hippocampus and cortex by dysregulating neurogenesis. Our study is the first to discover the detrimental impact of TFEB overexpression on neurogenesis during embryonic development, which has important reference significance in future TFEB overexpression interventions in NSCs for treatment.

2.
Brain Behav Immun ; 120: 499-512, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38944162

RESUMEN

The gut microbiota and neurological development of neonatal mice are susceptible to environmental factors that may lead to altered behavior into adulthood. However, the role that changed gut microbiota and neurodevelopment early in life play in this needs to be clarified. In this study, by modeling early-life environmental changes by cross-fostering BALB/c mice, we revealed the effects of the environment during the critical period of postnatal development on adult social behavior and their relationship with the gut microbiota and the nervous system. The neural projections exist between the ascending colon and oxytocin neurons in the paraventricular nuclei (PVN), peripheral oxytocin levels and PVN neuron numbers decreased after cross-fostering, and sex-specific alteration in gut microbiota and its metabolites may be involved in social impairments and immune imbalances brought by cross-fostering via the gut-brain axis. Our findings also suggest that social cognitive impairment may result from a combination of PVN oxytocinergic neurons, gut microbiota, and metabolites.

3.
Pharmacol Res ; 202: 107126, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432446

RESUMEN

PD-1 blockade therapy has made great breakthroughs in treatment of multiple solid tumors. However, patients with microsatellite-stable (MSS) colorectal cancer (CRC) respond poorly to anti-PD-1 immunotherapy. Although CRC patients with microstatellite instability (MSI) or microsatellite instability-high (MSI-H) can benefit from PD-1 blockade therapy, there are still some problems such as tumor recurrence. Tumor-associated macrophages (TAMs), most abundant immune components in tumor microenvironment (TME), largely limit the therapeutic efficacy of anti-PD-1 against CRC. The CSF1/CSF1R pathway plays a key role in regulating macrophage polarization, and blocking CSF1R signaling transduction may be a potential strategy to effectively reprogram macrophages and remodel TME. Here, we found that increasing expression of CSF1R in macrophages predicted poor prognosis in CRC cohort. Furthermore, we discovered a novel potent CSF1R inhibitor, PXB17, which significantly reprogramed M2 macrophages to M1 phenotype. Mechanically, PXB17 significantly blocked activation of PI3K/AKT/mTORC1 signaling, resulting in inhibition of cholesterol biosynthesis. Results from 3D co-culture system suggested that PXB17-repolarized macrophages could induce infiltration of CD8+ T lymphocytes in tumors and improve the immunosuppressive microenvironment. In vivo, PXB17 significantly halted CRC growth, with a stronger effect than PLX3397. In particular, PXB17 potently enhanced therapeutic activity of PD-1 mAb in CT-26 (MSS) model and prevented tumor recurrence in MC-38 (MSI-H) model by promoting formation of long-term memory immunity. Our study opens a new avenue for CSF1R in tumor innate and adaptive anti-tumor immunomodulatory activity and suggests that PXB17 is a promising immunotherapy molecule for enhancing the efficacy of PD-1 mAb or reducing tumor recurrence of CRC.


Asunto(s)
Neoplasias Colorrectales , Macrófagos Asociados a Tumores , Humanos , Receptor de Muerte Celular Programada 1 , Fosfatidilinositol 3-Quinasas , Recurrencia Local de Neoplasia , Neoplasias Colorrectales/genética , Microambiente Tumoral
4.
Environ Res ; 251(Pt 1): 118571, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38431066

RESUMEN

Supercritical water oxidation (SCWO) has been regarded as a new and efficient technology for the harmless treatment and energy utilization of organic wastes, resulting in the quickly homogeneous oxidation between organics and oxidizers and the former being wholly degraded into small environment-friendly green molecules such as H2O and N2 and inorganic salts. This paper systematically analyzed the influencing behavior and mechanisms of the reaction factors, such as temperature, pressure, residence time, oxidant type, oxidation coefficient, and the concentration and pH values of the raw material, on the treatment effect of organic wastes. For most organic wastes, the SCWO conditions at 550 °C with a residence time of 1min and an oxidation coefficient of 100% can meet the removal rate of more than 99%. To further enhance the degradation rate of organics, the principles, implementation cases, and related equipment components of general enhancement technologies of supercritical water oxidation were discussed, such as fractional oxygen injection, auxiliary fuel co-oxidation, and hydrothermal flame-assisted degradation. This paper proposes a novel supercritical flame-assisted oxidation process in which the reactor performs preheating, corrosion protection, and desalination functions. The use of additive-enhanced oxidation, segmented oxidation, and supercritical hydrothermal flame-assisted oxidation has achieved good results in the complicated treatment process of brutal degradation of organic matter.


Asunto(s)
Oxidación-Reducción , Agua , Agua/química , Compuestos Orgánicos/química , Eliminación de Residuos Líquidos/métodos , Temperatura
5.
Cell Mol Neurobiol ; 43(5): 2129-2147, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36239833

RESUMEN

The dorsal hippocampus is involved in behavioral avoidance regulation. It is unclear how experiences such as the neonatal stress of maternal deprivation (MD) and post-weaning environmental enrichment (EE) affect avoidance behavior and the dorsal hippocampal parameters, including neuronal morphology, corticotrophin-releasing hormone (CRH) signaling, and oxytocin receptor (OTR) level. In male BALB/c mice, we found that MD impaired avoidance behavior in the step-on test compared to non-MD and EE rearing conditions could alleviate that partially. MD increased neuronal branches in the CA1 but decreased synaptic connection levels in the CA2, CA3, and DG. Meanwhile, MD increased the CA1's OTR levels, which negatively correlated with nucleus densities. MD also increased the CA1's and CA2's CRH levels, which positively correlated with CRHR1 levels. However, MD statistically elevated the CA3's CRH receptor 1 (CRHR1) levels, which negatively correlated with nucleus densities and, probably, synaptic connection levels in the CA3. The additive effects of MD and EE maintained similar CRH levels and CRHR1 levels as well as OTR levels in the hippocampal areas as the additive of non-MD and non-EE. However, the presence of MD and EE still decreased the CA1's neuronal branches and the CA2's and DG's synaptic connection levels. The study illustrates how MD and EE affect avoidance behaviors, hippocampal neuron morphology, and CRH and OTR levels. The results indicate that the late-life environmental improvement partially restores the alterations in dorsal hippocampal areas induced by early life stress.


Asunto(s)
Hipocampo , Receptores de Oxitocina , Ratones , Animales , Masculino , Hipocampo/metabolismo , Neuronas/metabolismo , Hormona Liberadora de Corticotropina/metabolismo
6.
Nano Lett ; 21(20): 8800-8807, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34644096

RESUMEN

Memristor devices that exhibit high integration density, fast speed, and low power consumption are candidates for neuromorphic devices. Here, we demonstrate a filament-based memristor using p-type SnS as the resistive switching material, exhibiting superlative metrics such as a switching voltage ∼0.2 V, a switching speed faster than 1.5 ns, high endurance switching cycles, and an ultralarge on/off ratio of 108. The device exhibits a power consumption as low as ∼100 fJ per switch. Chip-level simulations of the memristor based on 32 × 32 high-density crossbar arrays with 50 nm feature size reveal on-chip learning accuracy of 87.76% (close to the ideal software accuracy 90%) for CIFAR-10 image classifications. The ultrafast and low energy switching of p-type SnS compared to n-type transition metal dichalcogenides is attributed to the presence of cation vacancies and van der Waals gap that lower the activation barrier for Ag ion migration.

7.
Pharmazie ; 76(9): 404-411, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34481529

RESUMEN

According to the latest statistics from WHO for all cancers, lung cancer tops the list with a 14.5% prevalence and a 22% death rate in men, similar to the prevalence in women, which is 13.8%. It is also the number one killer of cancer in China, with 40 in every 100,000 people suffering from lung cancer. HIF-1α is widely present in human cells in hypoxic environments. It regulates the body's response to hypoxia, cell oxygen balance, and hypoxia gene expression; participates in the proliferation and apoptosis of non-small cell lung cancer cells; participates in the invasion, metastasis, and neovascularization of tumor tissues; and affects the treatment and prognosis of non-small cell lung cancer. In view of the role of HIF-1α in the occurrence and development of non-small cell lung cancer, blocking HIF-1α by use of a single medication or combination chemotherapy has become a research hotspot. This review summarizes the role of HIF-1α in non-small cell lung cancer and provides new ideas for the treatment of this cancer type by synthesizing the research results of various authors.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Hipoxia de la Célula , Línea Celular Tumoral , Femenino , Humanos , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pronóstico
8.
Pharmazie ; 76(4): 127-131, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33849695

RESUMEN

Ischemic stroke is an injury caused by temporary or permanent cerebral vascular occlusion. It has a high incidence, mortality, and disability rate in clinical practice, and thus poses a considerable threat to public health as one of the top three major conditions endangering human health. Vascular endothelial growth factor is a specific mitogen of endothelial cells and a protein factor that is closely related to ischemic stroke. Vascular endothelial growth factor plays an important role in a multitude of physiological and pathological conditions. As a potential angiogenic protein for the treatment of ischemic stroke, vascular endothelial growth factor plays a role in promoting angiogenesis and neuroprotection and regeneration. At the same time, it plays a role in brain edema, collateral artery formation, and atherosclerosis. An increase in vascular endothelial growth factor levels contributes to the early pathological changes in patients with stroke and is closely related to the formation of cerebral edema in ischemic stroke complications. In theory, the neuroprotective and angiogenic effects of vascular endothelial growth factor make it an ideal candidate for the treatment of stroke. Here, we review the mechanism by which vascular endothelial growth factor participates in various stages of ischemic stroke and its prospects for use in the treatment of ischemic stroke.


Asunto(s)
Edema Encefálico/fisiopatología , Accidente Cerebrovascular Isquémico/fisiopatología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Inductores de la Angiogénesis/farmacología , Animales , Edema Encefálico/tratamiento farmacológico , Humanos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Neovascularización Fisiológica/efectos de los fármacos , Neovascularización Fisiológica/fisiología , Fármacos Neuroprotectores/farmacología , Factor A de Crecimiento Endotelial Vascular/uso terapéutico
9.
Acc Chem Res ; 52(8): 2124-2135, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31373796

RESUMEN

Plasmons, collective oscillations of conduction-band electrons in nanoscale metals, are well-known phenomena in colloidal gold and silver nanocrystals that produce brilliant visible colors in these materials that depend on the nanocrystal size and shape. Under illumination at or near the plasmon bands, gold and silver nanocrystals exhibit properties that enable fascinating biological applications: (i) the nanocrystals elastically scatter light, providing a straightforward way to image them in complex aqueous environments; (ii) the nanocrystals produce local electric fields that enable various surface-enhanced spectroscopies for sensing, molecular diagnostics, and boosting of bound fluorophore performance; (iii) the nanocrystals produce heat, which can lead to chemical transformations at or near the nanocrystal surface and can photothermally destroy nearby cells. While all the above-mentioned applications have already been well-demonstrated in the literature, this Account focuses on several other aspects of these nanomaterials, in particular gold nanorods that are approximately the size of viruses (diameters of ∼10 nm, lengths up to 100 nm). Absolute extinction, scattering, and absorption properties are compared for gold nanorods of various absolute dimensions, and references for how to synthesize gold nanorods with four different absolute dimensions are provided. Surface chemistry strategies for coating nanocrystals with smooth or rough shells are detailed; specific examples include mesoporous silica and metal-organic framework shells for porous (rough) coatings and polyelectrolyte layer-by-layer wrapping for "smooth" shells. For self-assembled-monolayer molecular coating ligands, the smoothest shells of all, a wide range of ligand densities have been reported from many experiments, yielding values from less than 1 to nearly 10 molecules/nm2 depending on the nanocrystal size and the nature of the ligand. Systematic studies of ligand density for one particular ligand with a bulky headgroup are highlighted, showing that the highest ligand density occurs for the smallest nanocrystals, even though these ligand headgroups are the most mobile as judged by NMR relaxation studies. Biomolecular coronas form around spherical and rod-shaped nanocrystals upon immersion into biological fluids; these proteins and lipids can be quantified, and their degree of adsorption depends on the nanocrystal surface chemistry as well as the biophysical characteristics of the adsorbing biomolecule. Photothermal adsorption and desorption of proteins on nanocrystals depend on the enthalpy of protein-nanocrystal surface interactions, leading to light-triggered alteration in protein concentrations near the nanocrystals. At the cellular scale, gold nanocrystals exert genetic changes at the mRNA level, with a variety of likely mechanisms that include alteration of local biomolecular concentration gradients, changes in mechanical properties of the extracellular matrix, and physical interruption of key cellular processes-even without plasmonic effects. Microbiomes, both organismal and environmental, are the likely first point of contact of nanomaterials with natural living systems; we see a major scientific frontier in understanding, predicting, and controlling microbe-nanocrystal interactions, which may be augmented by plasmonic effects.


Asunto(s)
Nanopartículas del Metal/química , Nanotubos/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/efectos de la radiación , Oro/química , Oro/efectos de la radiación , Humanos , Hipertermia Inducida/métodos , Luz , Nanopartículas del Metal/efectos de la radiación , Ratones , Nanotubos/efectos de la radiación , Pseudomonas aeruginosa/efectos de los fármacos , Resonancia por Plasmón de Superficie
10.
Chemphyschem ; 21(22): 2643-2650, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-32966659

RESUMEN

A series of carbon-coated, nitrogen-doped titanium dioxide photocatalysts was produced and characterized. N-doped TiO2 powder samples were prepared using a sol-gel method and subsequently used for making doped-TiO2 thin films on glass substrates. Carbon layers were coated on the films by a thermal decomposition method using catechol. Diffuse reflectance spectra and Mott-Schottky analyses of the samples proved that nitrogen doping and carbon coating can slightly lower the band gap of TiO2 , broaden its absorption to visible light and enhance its n-type character. According to photocatalytic tests against model contaminants, carbon-coated nitrogen-doped TiO2 films have better performance than simple TiO2 on the degradation of Rhodamine B dye molecules, but are poorly effective for degrading 4-chlorophenol molecules. Several possible explanations are proposed for this result, supported by scavenging experiments. This reveals the importance of a broad substrate scope when assessing new photocatalytic materials for water treatment, something which is often overlooked in many literature studies.

11.
Prep Biochem Biotechnol ; 50(10): 1023-1030, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32552438

RESUMEN

Poly-γ-glutamate (γ-PGA) is a natural macromolecule peptide, and is widely used in the food, medicine, and pharmaceutical industries. In this study, heat- and osmotic shock were used to improve the production of γ-PGA in Bacillus subtilis ZJS18, and its molecular mechanism was explored. The results indicated that the heat- and osmotic shock significantly promoted the production of γ-PGA owing to the stress response of B. subtilis cells to adverse environment. The highest concentrations of γ-PGA reached 14.53 and 15.98 g/l under heat- and osmotic shock, respectively. The activities of five enzymes related to the metabolism of the endogenous glutamate were determined and analyzed. It was found that the activities of glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase, glutamate dehydrogenase and glutamate synthase were significantly altered during heat- and osmotic shock, while the activity of α-ketoglutarate dehydrogenase only showed a little alteration. This study provides a basis for the industrial production and use of γ-PGA, and for understanding its biosynthetic mechanism in B. subtilis ZJS18.


Asunto(s)
Bacillus subtilis/metabolismo , Ácido Poliglutámico/análogos & derivados , Bacillus subtilis/enzimología , Vías Biosintéticas , Ácido Glutámico/metabolismo , Calor , Microbiología Industrial , Presión Osmótica , Ácido Poliglutámico/metabolismo
12.
J Cell Physiol ; 234(8): 13145-13156, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30584667

RESUMEN

OBJECTIVES: In our research, we aimed to investigate the roles of CC-chemokine receptor 7 (CCR7) and relevant signaling pathways in Leishmania major-infected human dendritic cells (DCs). METHODS: Differentially expressed genes (DEGs) in L. major-infected human DCs were selected out and visualized using R program. Kyoto Encyclopedia of Genes and Genomes pathway analysis was conducted for investigation of significantly enriched signaling pathways and Gene Ontology enrichment analysis was carried out for the unveiling of enriched Molecular Functions and Biological Processes in L. major-infected human DCs. Besides, Hub gene was screened out using weighted gene coexpression network analysis and Cytoscape. In addition, enzyme-linked immunosorbent assay and real-time quantitative polymerase chain reaction were used for detection of relative expression of CCR7, interleukin-12 (IL-12), and interferon-γ (IFN-γ) in L. major-infected human DCs and western blot analysis was used for detection of relative expression of CCR7 and other proteins in JAK-STAT signaling pathway in L. major-infected human DCs. RESULTS: CCR7 was upregulated and both chemokine and JAK-STAT signaling pathway were activated in L. major-infected human DCs. During the L. major infection, total number of L. major-infected human DCs were increased, as well as the relative expression levels of CCR7, IL-12, and IFN-γ and proteins in the JAK-STAT signaling pathway. Overexpression of CCR7 not only increased expression levels of IL-12 and IFN-γ but also activated the JAK-STAT signaling pathway to affect the leishmaniasis progression. CONCLUSION: L. major infection-induced activation of CCR7, as well as JAK2 and STAT1, might well upregulate the expression of BAX yet suppress the expression of both Bcl2 and c-Jun to affect leishmaniasis progression.


Asunto(s)
Células Dendríticas/metabolismo , Leishmaniasis Cutánea/metabolismo , Receptores CCR7/metabolismo , Transducción de Señal/fisiología , Células Dendríticas/inmunología , Humanos , Quinasas Janus/inmunología , Quinasas Janus/metabolismo , Leishmania major , Leishmaniasis Cutánea/inmunología , Receptores CCR7/inmunología , Factores de Transcripción STAT/inmunología , Factores de Transcripción STAT/metabolismo
13.
Cells Tissues Organs ; 207(3-4): 165-176, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31726456

RESUMEN

OBJECTIVE: To elaborate the mechanism of miR-150 in the regulation of the NF-κB signal pathway in intervertebral disc degeneration (IDD) by targeting P2X7. METHODS: The degenerative and normal intervertebral disc tissues were collected to detect the expressions of miR-150 and P2X7. Nucleus pulposus cells were transfected and divided into different groups. Cell apoptosis was determined by flow cytometry and TUNEL staining. The expressions of IL-6, TNF-α, MMP-3, MMP-13, Cox-2, iNOS, collagen II and aggrecan, as well as NF-κB-associated proteins were measured by qRT-PCR and Western blotting. Furthermore, IDD rat models were established to validate the role of miR-150 in vivo. RESULTS: miR-150 was down-regulated but P2X7 was up-regulated in the degenerative intravertebral disc tissues. The apoptosis of nucleus pulposus cells in the IL-1ß-induced group with the transfection of miR-150 mimic and siP2X7 was significantly decreased, with reduced levels of IL-6, TNF-α, MMP-3, MMP-13, Cox-2 and iNOS, increased levels of collagen II and aggrecan, as well as decreased P2X7, p-p65/p65 and cleaved caspase-3. However, the above factors showed an opposite tendency after treatment with miR-150 inhibitor. Furthermore, the P2X7 siRNA transfection could reverse the effects caused by miR-150 inhibitor. Simultaneously, pcDNA P2X7 transfection also inhibited the function of miR-150 mimic in IL-1ß-induced nucleus pulposus cells. In vivoexperiments further verified the protective role of miR-150 in IDD rats. CONCLUSION: miR-150 may alleviate the degeneration of the intervertebral disc partially since it could restrict the NF-κB pathway by targeting P2X7, and thereby inhibiting IL-1ß-induced matrix catabolism, inflammatory responses and apoptosis of the nucleus pulposus cells.


Asunto(s)
Degeneración del Disco Intervertebral/genética , MicroARNs/genética , FN-kappa B/genética , Receptores Purinérgicos P2X7/genética , Adulto , Animales , Células Cultivadas , Regulación hacia Abajo , Femenino , Humanos , Degeneración del Disco Intervertebral/patología , Masculino , Persona de Mediana Edad , Ratas , Transducción de Señal , Regulación hacia Arriba
14.
Nano Lett ; 18(5): 3229-3234, 2018 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-29668290

RESUMEN

Synaptic computation, which is vital for information processing and decision making in neural networks, has remained technically challenging to be demonstrated without using numerous transistors and capacitors, though significant efforts have been made to emulate the biological synaptic transmission such as short-term and long-term plasticity and memory. Here, we report synaptic computation based on Joule heating and versatile doping induced metal-insulator transition in a scalable monolayer-molybdenum disulfide (MoS2) device with a biologically comparable energy consumption (∼10 fJ). A circuit with our tunable excitatory and inhibitory synaptic devices demonstrates a key function for realizing the most precise temporal computation in the human brain, sound localization: detecting an interaural time difference by suppressing sound intensity- or frequency-dependent synaptic connectivity. This Letter opens a way to implement synaptic computing in neuromorphic applications, overcoming the limitation of scalability and power consumption in conventional CMOS-based neuromorphic devices.

15.
Anal Chem ; 90(24): 14216-14221, 2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30456938

RESUMEN

The quality of input data in deep learning is tightly associated with the ultimate performance of the machine learner. Taking advantage of the unique merits of surface-enhanced Raman scattering (SERS) methodology in the collection and construction of a database (e.g., abundant intrinsic fingerprint information, noninvasive data acquisition process, strong anti-interfering ability, etc.), herein we set up a SERS-based database of deoxyribonucleic acid (DNA), suitable for artificial intelligence (AI)-based sensing applications. The database is collected and analyzed by silver nanoparticles (Ag NPs)-decorated silicon wafer (Ag NPs@Si) SERS chip, followed by training with a deep neural network (DNN). As proof-of-concept applications, three kinds of representative tumor suppressor genes, i.e., p16, p21, and p53 fragments, are readily discriminated in a label-free manner. Prominent and reproducible SERS spectra of these DNA molecules are collected and employed as input data for DNN learning and training, which enables selective discrimination of DNA target(s). The accuracy rate for the recognition of specific DNA target reached 90.28%.


Asunto(s)
Inteligencia Artificial , ADN/análisis , Espectrometría Raman/métodos , Proteínas Supresoras de Tumor/genética , Bases de Datos Factuales , Dispositivos Laboratorio en un Chip , Nanopartículas del Metal/química , Silicio/química , Plata/química , Proteína p53 Supresora de Tumor/genética
16.
Small ; 14(51): e1802188, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30427578

RESUMEN

Neuromorphic systems aim to implement large-scale artificial neural network on hardware to ultimately realize human-level intelligence. The recent development of nonsilicon nanodevices has opened the huge potential of full memristive neural networks (FMNN), consisting of memristive neurons and synapses, for neuromorphic applications. Unlike the widely reported memristive synapses, the development of artificial neurons on memristive devices has less progress. Sophisticated neural dynamics is the major obstacle behind the lagging. Here a rich dynamics-driven artificial neuron is demonstrated, which successfully emulates partial essential neural features of neural processing, including leaky integration, automatic threshold-driven fire, and self-recovery, in a unified manner. The realization of bioplausible artificial neurons on a single device with ultralow power consumption paves the way for constructing energy-efficient large-scale FMNN and may boost the development of neuromorphic systems with high density, low power, and fast speed.


Asunto(s)
Redes Neurales de la Computación , Animales , Humanos
17.
Sensors (Basel) ; 18(2)2018 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-29438336

RESUMEN

In ultrasonic array imaging, 3D ultrasonic wavefields are normally recorded by an ultrasonic piezo array transducer. Its performance is limited by the configuration and size of the array transducer. In this paper, a method based on digital holographic interferometry is proposed to record the 3D ultrasonic wavefields instead of the array transducer, and the measurement system consisting of a pulsed laser, ultrasonic excitation, and synchronization and control circuit is designed. A consecutive sequence of holograms of ultrasonic wavefields are recorded by the system. The interferograms are calculated from the recorded holograms at different time sequence. The amplitudes and phases of the transient ultrasonic wavefields are recovered from the interferograms by phase unwrapping. The consecutive sequence of transient ultrasonic wavefields are stacked together to generate 3D ultrasonic wavefields. Simulation and experiments are carried out to verify the proposed technique, and preliminary results are presented.

18.
Small ; 13(20)2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28296020

RESUMEN

Memristive devices, having a huge potential as artificial synapses for low-power neural networks, have received tremendous attention recently. Despite great achievements in demonstration of plasticity and learning functions, little progress has been made in the repeatable analog resistance states of memristive devices, which is, however, crucial for achieving controllable synaptic behavior. The controllable behavior of synapse is highly desired in building neural networks as it helps reduce training epochs and diminish error probability. Fundamentally, the poor repeatability of analog resistance states is closely associated with the random formation of conductive filaments, which consists of oxygen vacancies. In this work, graphene quantum dots (GQDs) are introduced into memristive devices. By virtue of the abundant oxygen anions released from GQDs, the GQDs can serve as nano oxygen-reservoirs and enhance the localization of filament formation. As a result, analog resistance states with highly tight distribution are achieved with nearly 85% reduction in variations. In addition the insertion of GQDs can alter the energy band alignment and boost the tunneling current, which leads to significant reduction in both switching voltages and their distribution variations. This work may pave the way for achieving artificial neural networks with accurate and efficient learning capability.

19.
Crit Rev Food Sci Nutr ; 57(18): 3840-3849, 2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-27171656

RESUMEN

Phycocyanin is an important light-harvesting pigment antenna protein in cyanobacteria, rhodophyta, cryptophyta, and glaucophyta, with a variety of bioactivities. The introduction of purification and bioactivities of phycocyanin contributes to a significant improvement in developing it into final processed products. In fact, the knowledge of phycocyanin has experienced a rapid increase in the past 20 years, and has promoted the relevant technological revolution with a decisive contribution to final application. The purpose of this review is to critically introduce the present knowledge of purification and bioactivities of phycocyanin, and to illustrate main problems and prospects.


Asunto(s)
Cianobacterias/metabolismo , Ficocianina/aislamiento & purificación , Ficocianina/farmacología , Rhodophyta/metabolismo , Humanos , Ficocianina/química
20.
J Med Chem ; 67(8): 6854-6879, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38593344

RESUMEN

Blocking CSF-1/CSF-1R pathway has emerged as a promising strategy to remodel tumor immune microenvironment (TME) by reprogramming tumor-associated macrophages (TAMs). In this work, a novel CSF-1R inhibitor C19 with a highly improved pharmacokinetic profile and in vivo anticolorectal cancer (CRC) efficiency was successfully discovered. C19 could effectively reprogram M2-like TAMs to M1 phenotype and reshape the TME by inducing the recruitment of CD8+ T cells into tumors and reducing the infiltration of immunosuppressive Tregs/MDSCs. Deeper mechanistic studies revealed that C19 facilitated the infiltration of CD8+ T cells by enhancing the secretion of chemokine CXCL9, thus significantly potentiating the anti-CRC efficiency of PD-1 blockade. More importantly, C19 combined with PD-1 mAb could induce durable antitumor immune memory, effectively overcoming the recurrence of CRC. Taken together, our findings suggest that C19 is a promising therapeutic option for sensitizing CRC to anti-PD-1 therapy.


Asunto(s)
Neoplasias Colorrectales , Inmunoterapia , Receptor de Factor Estimulante de Colonias de Macrófagos , Neoplasias Colorrectales/tratamiento farmacológico , Animales , Humanos , Ratones , Inmunoterapia/métodos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/síntesis química , Antineoplásicos/química , Microambiente Tumoral/efectos de los fármacos , Ratones Endogámicos BALB C , Línea Celular Tumoral , Femenino , Descubrimiento de Drogas , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Masculino , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología , Ratones Endogámicos C57BL , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología
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