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1.
Opt Express ; 31(16): 26418-26434, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710504

RESUMEN

In this work, we propose to use various artificial neural network (ANN) structures for modeling and compensation of intra- and inter-subcarrier fiber nonlinear interference in digital subcarrier multiplexing (DSCM) optical transmission systems. We perform nonlinear channel equalization by employing different ANN cores including convolutional neural networks (CNN) and long short-term memory (LSTM) layers. First, we develop a fiber nonlinearity compensation for DSCM systems based on a fully-connected network across all subcarriers. In subsequent steps, and borrowing from the perturbation analysis of fiber nonlinearity, we gradually upgrade proposed designs towards modular structures with better performance-complexity advantages. Our study shows that putting proper macro structures in design of ANN nonlinear equalizers in DSCM systems can be crucial in development of practical solutions for future generations of coherent optical transceivers.

2.
Part Fibre Toxicol ; 20(1): 8, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-36899356

RESUMEN

BACKGROUND: Montmorillonite (Mt) and its derivatives are now widely used in industrial and biomedical fields. Therefore, safety assessments of these materials are critical to protect human health after exposure; however, studies on the ocular toxicity of Mt are lacking. In particular, varying physicochemical characteristics of Mt may greatly alter their toxicological potential. To explore the effects of such characteristics on the eyes, five types of Mt were investigated in vitro and in vivo for the first time, and their underlying mechanisms studied. RESULTS: The different types of Mt caused cytotoxicity in human HCEC-B4G12 corneal cells based on analyses of ATP content, lactate dehydrogenase (LDH) leakage, cell morphology, and the distribution of Mt in cells. Among the five Mt types, Na-Mt exhibited the highest cytotoxicity. Notably, Na-Mt and chitosan-modified acidic Na-Mt (C-H-Na-Mt) induced ocular toxicity in vivo, as demonstrated by increases corneal injury area and the number of apoptotic cells. Na-Mt and C-H-Na-Mt also induced reactive oxygen species (ROS) generation in vitro and in vivo, as indicated by 2',7'-dichlorofluorescin diacetate and dihydroethidium staining. In addition, Na-Mt activated the mitogen-activated protein kinase signaling pathway. The pretreatment of HCEC-B4G12 cells with N-acetylcysteine, an ROS scavenger, attenuated the Na-Mt-induced cytotoxicity and suppressed p38 activation, while inhibiting p38 activation with a p38-specific inhibitor decreased Na-Mt-induced cytotoxicity. CONCLUSIONS: The results indicate that Mt induces corneal toxicity in vitro and in vivo. The physicochemical properties of Mt greatly affect its toxicological potential. Furthermore, ROS generation and p38 activation contribute at least in part to Na-Mt-induced toxicity.


Asunto(s)
Bentonita , Neuropatía Óptica Tóxica , Humanos , Especies Reactivas de Oxígeno/metabolismo , Bentonita/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/farmacología , Apoptosis
3.
J Nanobiotechnology ; 20(1): 146, 2022 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35305659

RESUMEN

BACKGROUND: Silica nanoparticles (SiO2 NPs) are extensively applied in the biomedical field. The increasing medical application of SiO2 NPs has raised concerns about their safety. However, studies on SiO2 NP-induced retinal toxicity are lacking. METHODS: We investigated the retinal toxicity of SiO2 NPs with different sizes (15 and 50 nm) in vitro and in vivo along with the underlying mechanisms. The cytotoxicity of SiO2 NPs with different sizes was assessed in R28 human retinal precursor cells by determining the ATP content and LDH release. The cell morphologies and nanoparticle distributions in the cells were analyzed by phase-contrast microscopy and transmission electron microscopy, respectively. The mitochondrial membrane potential was examined by confocal laser scanning microscopy. The retinal toxicity induced by SiO2 NPs in vivo was examined by immunohistochemical analysis. To further investigate the mechanism of retinal toxicity induced by SiO2 NPs, reactive oxygen species (ROS) generation, glial cell activation and inflammation were monitored. RESULTS: The 15-nm SiO2 NPs were found to have higher cytotoxicity than the larger NPs. Notably, the 15-nm SiO2 NPs induced retinal toxicity in vivo, as demonstrated by increased cell death in the retina, TUNEL-stained retinal cells, retinal ganglion cell degeneration, glial cell activation, and inflammation. In addition, The SiO2 NPs caused oxidative stress, as demonstrated by the increase in the ROS indicator H2DCF-DA. Furthermore, the pretreatment of R28 cells with N-acetylcysteine, an ROS scavenger, attenuated the ROS production and cytotoxicity induced by SiO2 NPs. CONCLUSIONS: These results provide evidence that SiO2 NPs induce size-dependent retinal toxicity and suggest that glial cell activation and ROS generation contribute to this toxicity.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Supervivencia Celular , Humanos , Nanopartículas/química , Nanopartículas/toxicidad , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Dióxido de Silicio/química
4.
Opt Express ; 27(13): 18787-18793, 2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31252815

RESUMEN

Continuous real-time measurements are demonstrated from a 200Gb/s format configurable CFP transceiver that uses dual-polarization probabilistic-shaped 16QAM (DP-PS16QAM) modulation. Placed in a 50GHz coherent DWDM transmission system, DP-PS16QAM achieves a back-to-back 1.8dB OSNR gain over uniform DP-16QAM. It also transports over 1940km with EDFA-only amplification, thus doubling propagation distance of uniform DP-16QAM. Furthermore, a 1Tb/s super-channel consisting of five 200Gb/s DP-PS16QAM sub-carriers is placed in a 200GHz grid, and it achieves over 1600km transmission and 5b/s/Hz SE with a raw SE at 6.86b/s/Hz.

5.
Arch Toxicol ; 92(2): 717-728, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28993908

RESUMEN

4-Methoxy-TEMPO, a derivative of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), is a stable nitroxide radical and is generally used in organic and pharmaceutical syntheses for the oxidation of alcohols. Previously, we reported the involvement of reactive oxygen species (ROS) and c-Jun N-terminal kinases (JNK) in TEMPO-induced apoptosis in mouse L5178Y cells. In this study, we investigated 4-methoxy-TEMPO induced toxicity in human HepG2 hepatoma cells and its underlying mechanisms. Treatments with 4-methoxy-TEMPO (0.5-5 mM for 2-6 h) caused oxidative stress as demonstrated by increased intensity of the ROS indicator H2DCF-DA, decreased levels of glutathione. 4-Methoxy-TEMPO treatment also induced DNA damage as characterized by increased levels of DNA tail intensity in the Comet assay, increased phosphorylation of related proteins including γ-H2A.X, p-Chk1, and p-Chk2, and activation of MAPK signaling pathways. In addition, 4-methoxy-TEMPO also induced autophagy as demonstrated by the conversion of LC3B-I to II, decreased level of p62, and the appearance of GFP-LC3B punctae. To investigate the crosstalk between different signaling pathways, pretreatment of HepG2 with N-acetylcysteine, an ROS scavenger, attenuated 4-methoxy-TEMPO-induced DNA damage, suppressed JNK activation, and diminished autophagy induction. Furthermore, inhibiting JNK activation by a JNK-specific inhibitor, SP600125, decreased DNA damage levels induced by 4-methoxy-TEMPO. These results suggest that multiple mechanisms including ROS generation, DNA damage, and MAPK activation contribute to 4-methoxy-TEMPO-induced toxicity.


Asunto(s)
Autofagia/efectos de los fármacos , Óxidos N-Cíclicos/toxicidad , Daño del ADN , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Antracenos/farmacología , Ensayo Cometa , Células Hep G2 , Humanos , Sistema de Señalización de MAP Quinasas , Estrés Oxidativo/efectos de los fármacos
6.
Arch Toxicol ; 91(3): 1293-1307, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27369375

RESUMEN

Many usnic acid-containing dietary supplements have been marketed as weight loss agents, although severe hepatotoxicity and acute liver failure have been associated with their overuse. Our previous mechanistic studies revealed that autophagy, disturbance of calcium homeostasis, and ER stress are involved in usnic acid-induced toxicity. In this study, we investigated the role of oxidative stress and the Nrf2 signaling pathway in usnic acid-induced toxicity in HepG2 cells. We found that a 24-h treatment with usnic acid caused DNA damage and S-phase cell cycle arrest in a concentration-dependent manner. Usnic acid also triggered oxidative stress as demonstrated by increased reactive oxygen species generation and glutathione depletion. Short-term treatment (6 h) with usnic acid significantly increased the protein level for Nrf2 (nuclear factor erythroid 2-related factor 2), promoted Nrf2 translocation to the nucleus, up-regulated antioxidant response element (ARE)-luciferase reporter activity, and induced the expression of Nrf2-regulated targets, including glutathione reductase, glutathione S-transferase, and NAD(P)H quinone oxidoreductase-1 (NQO1). Furthermore, knockdown of Nrf2 with shRNA potentiated usnic acid-induced DNA damage and cytotoxicity. Taken together, our results show that usnic acid causes cell cycle dysregulation, DNA damage, and oxidative stress and that the Nrf2 signaling pathway is activated in usnic acid-induced cytotoxicity.


Asunto(s)
Benzofuranos/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal/efectos de los fármacos , Elementos de Respuesta Antioxidante/efectos de los fármacos , Benzofuranos/administración & dosificación , Daño del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Glutatión/metabolismo , Células Hep G2/efectos de los fármacos , Células Hep G2/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo , Puntos de Control de la Fase S del Ciclo Celular/efectos de los fármacos
7.
Proc Natl Acad Sci U S A ; 111(48): 17266-71, 2014 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-25411317

RESUMEN

Although initially responsive to chemotherapy, many patients with ovarian cancer subsequently develop relapsed and potentially fatal metastatic disease, which is thought to develop from cancer stem cells (CSCs) that are relatively resistant to conventional therapy. Here, we show that CSCs express a type I receptor tyrosine kinase-like orphan receptor (ROR1), which is expressed during embryogenesis and by many different cancers, but not normal postpartum tissues. Ovarian cancers with high levels of ROR1 had stem cell-like gene-expression signatures. Furthermore, patients with ovarian cancers with high levels of ROR1 had higher rates of relapse and a shorter median survival than patients with ovarian cancers that expressed low-to-negligible amounts of ROR1. We found that ROR1-positive (ROR1(+)) cells isolated from primary tumor-derived xenografts (PDXs) also expressed aldehyde dehydrogenase 1 (ALDH1) and had a greater capacity to form spheroids and to engraft immune-deficient mice than did ROR1-negative (ROR1(Neg)) ovarian cancer cells isolated from the same tumor population. Treatment with UC-961, an anti-ROR1 mAb, or shRNA silencing of ROR1 inhibited expression of the polycomb ring-finger oncogene, Bmi-1, and other genes associated with the epithelial-mesenchymal transition. Moreover, shRNA silencing of ROR1, depletion of ROR1(+) cells, or treatment with UC-961 impaired the capacity of ovarian cancer cells to form spheroids or tumor xenografts. More importantly, treatment with anti-ROR1 affected the capacity of the xenograft to reseed a virgin mouse, indicating that targeting ROR1 may affect CSC self-renewal. Collectively, these studies indicate that ovarian CSCs express ROR1, which contributes to their capacity to form tumors, making ROR1 a potential target for the therapy of patients with ovarian cancer.


Asunto(s)
Terapia Molecular Dirigida/métodos , Células Madre Neoplásicas/metabolismo , Neoplasias Ováricas/genética , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Línea Celular Tumoral , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Immunoblotting , Estimación de Kaplan-Meier , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Microscopía Confocal , Células Madre Neoplásicas/patología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/prevención & control , Pronóstico , Interferencia de ARN , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/inmunología , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/metabolismo , Trasplante Heterólogo
8.
Opt Express ; 24(20): 23531-23542, 2016 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-27828415

RESUMEN

An efficient trellis-based phase noise mitigation algorithm is proposed to highly improve the performance of coherent transmission systems, especially in high order modulation formats. The proposed method targets the coherent optical systems where the performance is limited by various sources of phase noise including laser line-width, fiber non-linearity, and phase noise induced by phase-locked loop. Considering hardware limitations of ultra-high data rate processing in optical systems, a hardware-efficient parallelized and pipelined architecture is utilized. Experimental results in 200 Gb/s DP-16QAM co-propagated with 10-G channels demonstrate significant performance improvement over other existing methods.

9.
Graefes Arch Clin Exp Ophthalmol ; 254(10): 1957-1965, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27405975

RESUMEN

PURPOSE: We aimed to evaluate the effect of IL-10 gene transfection on endothelial progenitor cells (EPCs) under inflammatory conditions, and explore the therapeutic potential of IL-10-transfected EPC transplantation on nonproliferative diabetic retinopathy (NPDR). METHODS: Lentivirus vectors encoding IL-10 were constructed and introduced into EPCs isolated from rat bone marrow. After exposure to recombinant rat TNF-α, abilities of nontransfected EPCs (non-EPCs) and EPCs transfected with normal control lentivirus (EPCs-GFP) or IL-10 expressing lentivirus (EPCs-IL-10-GFP) were assessed, including migration, adhesion, and tube formation. IL-10 production by EPCs-IL-10-GFP was determined by ELISA. Following 12 weeks after establishment of diabetes, diabetic rats were randomly injected with non-EPCs, EPCs-GFP, or EPCs-IL-10-GFP via tail vein. Expression of inflammatory factors and factors associated with nuclear factor-kappa B (NF-kB) signal pathway, retinal histological analysis, and retinal vascular permeability were assessed 2 weeks after transplantation. RESULTS: The detrimental effects of TNF-ɑ on the abilities of EPCs were significantly attenuated in EPCs-IL-10-GFP compared with non-EPCs and EPCs-GFP. The concentration of IL-10 in the EPCs-IL-10-GFP group was significantly higher than the non-EPCs and EPCs-GFP groups. Additionally, transplantation of EPCs-IL-10-GFP significantly inhibited inflammatory factors expression and activation of NF-kB signal pathway, improved retinal histological changes, and attenuated retinal vascular permeability. CONCLUSION: In conclusion, transplantation of IL-10-transfected EPCs significantly improved EPCs-mediated retinal vascular repair and subsequently suppressed NPDR progression. This was associated with inflammation suppression, at least partly via inhibiting the NF-kB signal pathway. Transplantation of IL-10-transfected EPCs may be a new strategy for treatment of NPDR.


Asunto(s)
Retinopatía Diabética/terapia , Células Progenitoras Endoteliales/trasplante , Interleucina-10/genética , Vasculitis Retiniana/terapia , Vasos Retinianos/fisiología , Transfección , Animales , Barrera Hematorretinal/fisiología , Western Blotting , Permeabilidad Capilar/fisiología , Trasplante de Células , Retinopatía Diabética/metabolismo , Retinopatía Diabética/fisiopatología , Células Progenitoras Endoteliales/metabolismo , Ensayo de Inmunoadsorción Enzimática , Regulación de la Expresión Génica/fisiología , Lentivirus/genética , Masculino , Microscopía Electrónica de Transmisión , FN-kappa B/metabolismo , Ratas , Ratas Wistar , Vasculitis Retiniana/metabolismo , Vasculitis Retiniana/fisiopatología , Factor de Necrosis Tumoral alfa/farmacología
10.
Int J Mol Sci ; 17(5)2016 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-27120595

RESUMEN

Tumor necrosis factor superfamily 15 (TNFSF15) is an endogenous neovascularization inhibitor and an important negative regulator of vascular homeostasis. This study aimed to explore the potential role of TNFSF15 in diabetic retinopathy. Vitreous TNFSF15 and VEGF levels in proliferative diabetic retinopathy (PDR) patients were detected by ELISA. Retinal expression of TNFSF15 and the content of tight junction proteins (TJPs) in rats were detected by immunohistochemistry and Western blot, respectively. The blood retinal barrier (BRB) permeability was evaluated using Evans Blue (EB) dye. The TNFSF15/VEGF ratio was decreased in the vitreous fluid of patients with PDR relative to the controls, even though the expression levels of TNFSF15 were higher. TNFSF15 was dramatically decreased one month later after diabetes induction (p < 0.001), and then increased three months later and thereafter. TNFSF15 treatment significantly protected the BRB in the diabetic animals. Diabetes decreased TJPs levels in the retina, and these changes were inhibited by TNFSF15 treatment. Moreover, TNFSF15 decreased activation of VEGF both in mRNA and protein levels caused by diabetes. These results indicate that TNFSF15 is an important inhibitor in the progression of DR and suggest that the regulation of TNFSF15 shows promise for the development of diabetic retinopathy treatment strategies.


Asunto(s)
Barrera Hematorretinal/metabolismo , Retinopatía Diabética/fisiopatología , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo , Anciano , Animales , Claudina-5/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Retinopatía Diabética/metabolismo , Femenino , Genes Reporteros , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Ocludina/metabolismo , Ratas , Ratas Wistar , Retina/metabolismo , Retina/patología , Vasos Retinianos/metabolismo , Proteínas de Uniones Estrechas/metabolismo , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/análisis , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Factor A de Crecimiento Endotelial Vascular/análisis
11.
Opt Express ; 23(15): 18988-95, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26367561

RESUMEN

We use 85-Gs/s digital-to-analog convertor (DAC), 85Gs/s analog-to-digital convertor (ADC), commercial optoelectronic (OE) components with an overall electronic 3dB-bandwidth of less than 15GHz, and novel digital signal processing (DSP) algorithms implemented in CMOS to realize real time coherent transceiver operation at a record baud rate of 61-Gbaud/s. Novel DSP approaches for mitigating narrow filtering effect is critical to acquire data clock, and to improve modem performance. With transmitter pre-emphasis, novel timing recovery, and soft output maximum likelihood sequence estimation (MLSE), we are able to achieve error free operation of single carrier 200-Gbit/s polarization division multiplexed quadrature phase shift keying (PDM-QPSK) after forward error correction (FEC) at 15.2dB OSNR with pre-FEC error rate of 1.4E-2, and single carrier 400-Gbit/s PDM 16-ary quadrature amplitude modulation (16QAM) after FEC at 30.2dB OSNR with pre-FEC error rate of 9.5E-3. Error free transmission for 200-Gbit/s PDM-QPSK and 400-Gbit/s PDM-16QAM was achieved after 1200km propagation with 6dB link margin and 80km propagation respectively.

12.
BMC Ophthalmol ; 14: 144, 2014 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-25421815

RESUMEN

BACKGROUND: P21 is one kind of cyclin-dependent kinase inhibitor that can prevent cells from going through the G1/S phase checkpoint and inhibit cell proliferation. Proliferative vitreoretinopathy (PVR) is a proliferative response in the eye. The aim of this study was to determine whether p21Waf1/Cip1 (p21) suppresses the proliferation and migration of retinal pigment epithelial (RPE) cells in vitro and controls PVR development in vivo. METHODS: Cell cycle analyses and transwell assays were conducted to assess cell proliferation characteristics and the migration ability of RPE cells after transfection with p21. Western blot and reverse-transcription polymerase chain reaction technologies were used to detect the expression of p21, CDK2 and cyclinE in RPE cells and rabbit retinal tissues. The impact of increasing p21 expression on PVR development was conducted by implantation of an adenovirus vector containing rabbit p21 (rAd-p21) in a PVR rabbit model. The prevalence of PVR and retinal detachment was determined by indirect ophthalmoscopy on days 3, 7, 14, and 21 after the injection of rAd-p21 into the vitreous. B scans and hematoxylin-eosin staining were employed to check rabbit retinas on day 21. RESULTS: Cell cycle analyses and transwell assays showed that p21 inhibited the proliferation and migration of RPE cells. Increased expression of p21 was detected in cultured RPE cells and rabbit retinas after transfection with the p21 gene, whereas levels of CDK2 and cyclinE were decreased. The increase in p21 expression effectively suppressed the development of PVR in a rabbit model. CONCLUSIONS: The increase in p21 expression in RPE cells not only inhibits the proliferation and migration of RPE cells in vitro, but also suppresses the development of PVR in vivo, which indicates its therapeutic potential in treating PVR.


Asunto(s)
Ciclina E/antagonistas & inhibidores , Quinasa 2 Dependiente de la Ciclina/antagonistas & inhibidores , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , Modelos Animales de Enfermedad , Epitelio Pigmentado de la Retina/patología , Vitreorretinopatía Proliferativa/prevención & control , Adenoviridae/genética , Animales , Western Blotting , Ciclo Celular , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Ciclina E/metabolismo , Quinasa 2 Dependiente de la Ciclina/metabolismo , Progresión de la Enfermedad , Citometría de Flujo , Vectores Genéticos , Humanos , Conejos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Vitreorretinopatía Proliferativa/metabolismo , Vitreorretinopatía Proliferativa/patología
13.
iScience ; 27(3): 109040, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38375232

RESUMEN

Biological visual systems intrinsically include multiple kinds of motion-sensitive neurons. Some of them have been successfully used to construct neural computational models for problem-specific engineering applications such as motion detection, object tracking, etc. Nevertheless, it remains unclear how these neurons' response mechanisms can be contributed to the topic of optimization. Hereby, the dragonfly's visual response mechanism is integrated with the inspiration of swarm evolution to develop a dragonfly visual evolutionary neural network for large-scale global optimization (LSGO) problems. Therein, a grayscale image input-based dragonfly visual neural network online outputs multiple global learning rates, and later, such learning rates guide a population evolution-like state update strategy to seek the global optimum. The comparative experiments show that the neural network is a competitive optimizer capable of effectively solving LSGO benchmark suites with 2000 dimensions per example and the design of an operational amplifier.

14.
J Zhejiang Univ Sci B ; 25(5): 361-388, 2024 May 15.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38725338

RESUMEN

Ceria nanoparticles (CeO2 NPs) have become popular materials in biomedical and industrial fields due to their potential applications in anti-oxidation, cancer therapy, photocatalytic degradation of pollutants, sensors, etc. Many methods, including gas phase, solid phase, liquid phase, and the newly proposed green synthesis method, have been reported for the synthesis of CeO2 NPs. Due to the wide application of CeO2 NPs, concerns about their adverse impacts on human health have been raised. This review covers recent studies on the biomedical applications of CeO2 NPs, including their use in the treatment of various diseases (e.|g., Alzheimer's disease, ischemic stroke, retinal damage, chronic inflammation, and cancer). CeO2 NP toxicity is discussed in terms of the different systems of the human body (e.|g., cytotoxicity, genotoxicity, respiratory toxicity, neurotoxicity, and hepatotoxicity). This comprehensive review covers both fundamental discoveries and exploratory progress in CeO2 NP research that may lead to practical developments in the future.


Asunto(s)
Cerio , Cerio/química , Cerio/toxicidad , Humanos , Animales , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química , Neoplasias/tratamiento farmacológico , Enfermedad de Alzheimer , Nanopartículas/toxicidad
15.
Adv Sci (Weinh) ; 10(30): e2302909, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37653617

RESUMEN

Retinal ischemia is involved in the occurrence and development of various eye diseases, including glaucoma, diabetic retinopathy, and central retinal artery occlusion. To the best of our knowledge, few studies have reported self-assembling peptide natural products for the suppression of ocular inflammation and oxidative stress. Herein, a self-assembling peptide GFFYE is designed and synthesized, which can transform the non-hydrophilicity of rhein into an amphiphilic sustained-release therapeutic agent, and rhein-based therapeutic nanofibers (abbreviated as Rh-GFFYE) are constructed for the treatment of retinal ischemia-reperfusion (RIR) injury. Rh-GFFYE significantly ameliorates oxidative stress and inflammation in an in vitro oxygen-glucose deprivation (OGD) model of retinal ischemia and a rat model of RIR injury. Rh-GFFYE also significantly enhances retinal electrophysiological recovery and exhibits good biocompatibility. Importantly, Rh-GFFYE also promotes the transition of M1-type macrophages to the M2 type, ultimately altering the pro-inflammatory microenvironment. Further investigation of the treatment mechanism indicates that Rh-GFFYE activates the PI3K/AKT/mTOR signaling pathway to reduce oxidative stress and inhibits the NF-κB and STAT3 signaling pathways to affect inflammation and macrophage polarization. In conclusion, the rhein-loaded nanoplatform alleviates RIR injury by modulating the retinal microenvironment. The findings are expected to promote the clinical application of hydrophobic natural products in RIR injury-associated eye diseases.


Asunto(s)
Productos Biológicos , Oftalmopatías , Nanofibras , Daño por Reperfusión , Ratas , Animales , Microglía/metabolismo , Nanofibras/uso terapéutico , Fosfatidilinositol 3-Quinasas , Estrés Oxidativo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Macrófagos/metabolismo , Inflamación/metabolismo , Oftalmopatías/metabolismo , Productos Biológicos/metabolismo , Péptidos/metabolismo , Isquemia
16.
Free Radic Biol Med ; 206: 162-179, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37380044

RESUMEN

Retinal ischemia-reperfusion (RIR) injury remains a major challenge that is detrimental to retinal cell survival in a variety of ocular diseases. However, current clinical treatments focus on a single pathological mechanism, making them unable to provide comprehensive retinal protection. A variety of natural products including ginsenoside Rg3 (Rg3) exhibit potent antioxidant and anti-inflammatory activities. Unfortunately, the hydrophobicity of Rg3 and the presence of various intraocular barriers limit its effective application in clinical settings. Hyaluronic acid (HA)- specifically binds to cell surface receptors, CD44, which is widely expressed in retinal pigment epithelial cells and M1-type macrophage. Here, we developed HA-decorated liposomes loaded with Rg3, termed Rg3@HA-Lips, to protect against retinal damage caused by RIR injury. Treatment with Rg3@HA-Lips significantly inhibited the oxidative stress induced by RIR injury. In addition, Rg3@HA-Lips promoted the transition of M1-type macrophage to the M2 type, ultimately reversing the pro-inflammatory microenvironment. The mechanism of Rg3@HA-Lips was further investigated and found that they can regulateSIRT/FOXO3a, NF-κB and STAT3 signaling pathways. Together with as well demonstrated good safety profiles, this CD44-targeted platform loaded with a natural product alleviates RIR injury by modulating the retinal microenvironment and present a potential clinical treatment strategy.


Asunto(s)
Microglía , Daño por Reperfusión , Humanos , Liposomas/farmacología , Estrés Oxidativo , Macrófagos , Daño por Reperfusión/tratamiento farmacológico
17.
Biomater Sci ; 11(14): 4822-4826, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37365951

RESUMEN

Low drug loading and instability of liposomes are two main challenges in the clinic. Herein, a liposomal platform from alternative pyridine-appended disulfidephospholipid (Pyr-SS-PC) was developed for delivering camptothecin (CPT) with high loading and stability. These Pyr-SS-PC lipids with π-π stacking open a general gate in the delivery of aromatic ring-containing drugs.


Asunto(s)
Camptotecina , Liposomas , Piridinas , Estabilidad de Medicamentos
18.
Colloids Surf B Biointerfaces ; 225: 113214, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36893664

RESUMEN

Pharmacologically active natural products have played a significant role in the history of drug development. They have acted as sources of therapeutic drugs for various diseases such as cancer and infectious diseases. However, most natural products suffer from poor water solubility and low bioavailability, limiting their clinical applications. The rapid development of nanotechnology has opened up new directions for applying natural products and numerous studies have explored the biomedical applications of nanomaterials loaded with natural products. This review covers the recent research on applying plant-derived natural products (PDNPs) nanomaterials, including nanomedicines loaded with flavonoids, non-flavonoid polyphenols, alkaloids, and quinones, especially their use in treating various diseases. Furthermore, some drugs derived from natural products can be toxic to the body, so the toxicity of them is discussed. This comprehensive review includes fundamental discoveries and exploratory advances in natural product-loaded nanomaterials that may be helpful for future clinical development.


Asunto(s)
Productos Biológicos , Nanopartículas , Sistemas de Liberación de Medicamentos , Nanotecnología , Nanomedicina
19.
Bioeng Transl Med ; 8(3): e10460, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37206232

RESUMEN

Retinal ischemia-reperfusion (RIR) injury is involved in the pathogenesis of various vision-threatening diseases. The overproduction of reactive oxygen species (ROS) is thought to be the main cause of RIR injury. A variety of natural products, including quercetin (Que), exhibit potent antioxidant activity. However, the lack of an efficient delivery system for hydrophobic Que and the presence of various intraocular barriers limit the effective retinal delivery of Que in clinical settings. In this study, we encapsulated Que into ROS-responsive mitochondria-targeted liposomes (abbreviated to Que@TPP-ROS-Lips) to achieve the sustained delivery of Que to the retina. The intracellular uptake, lysosome escape ability, and mitochondria targeting ability of Que@TPP-ROS-Lips were evaluated in R28 retinal cells. Treating R28 cells with Que@TPP-ROS-Lips significantly ameliorated the decrease in ATP content, ROS generation, and increase in the release of lactate dehydrogenase in an in vitro oxygen-glucose deprivation (OGD) model of retinal ischemia. In a rat model, the intravitreal injection of Que@TPP-ROS-Lips 24 h after inducing retinal ischemia significantly enhanced retinal electrophysiological recovery and reduced neuroinflammation, oxidative stress, and apoptosis. Que@TPP-ROS-Lips were taken up by retina for at least 14 days after intravitreal administration. Molecular docking and functional biological experiments revealed that Que targets FOXO3A to inhibit oxidative stress and inflammation. Que@TPP-ROS-Lips also partially inhibited the p38 MAPK signaling pathway, which contributes to oxidative stress and inflammation. In conclusion, our new platform for ROS-responsive and mitochondria-targeted drug release shows promise for the treatment of RIR injury and promotes the clinical application of hydrophobic natural products.

20.
Toxins (Basel) ; 14(10)2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36287946

RESUMEN

Furanocoumarins, the secondary metabolites of plants, are considered to be natural insecticides and fungicides because they prevent the invasion of plant pathogenic microorganisms and the predation of herbivorous insects. In this study, novel 2-arylfuranocoumarin derivatives were designed to synthesize by condensation, esterification, bromination, and Wittig reaction. The results showed an excellent photosensitive activity of 2-thiophenylfuranocoumarin (I34). Cell Counting Kit-8 detected that I34 could inhibit the proliferation of Spodoptera frugiperda (Sf9) cells in a time- and concentration-dependent manner under ultraviolet A (UV-A) light for 3 min. The inverted microscope revealed that cells treated with I34 swelled, the membrane was ruptured, and apoptotic bodies appeared. The flow cytometry detected that I34 could induce apoptosis of Sf9 cells, increase the level of intracellular reactive oxygen species (ROS), decrease the mitochondrial membrane potential, and block cell cycle arrest in the G2/M phase. Transmission electron microscopy detected cell mitochondrial cristae damage, matrix degradation, and mitochondrial vacuolation. Further enzyme activity detection revealed that the enzyme activities of apoptosis-related proteins caspase-3 and caspase-9 increased significantly (p < 0.05). Finally, Western blotting analysis detected that the phosphorylation level of Akt and Bad and the expression of the apoptosis inhibitor protein Bcl-XL were inhibited, cleaved-PARP and P53 were increased, and cytochrome C was released from the mitochondria into the cytoplasm. Moreover, under UV-A irradiation, I34 promoted the increase in ROS in Sf9 cells, activated the mitochondrial apoptotic signal transduction pathway, and finally, inhibited cell proliferation. Thus, novel furanocoumarins exhibit a potential application prospect as a biochemical pesticide.


Asunto(s)
Fungicidas Industriales , Furocumarinas , Insecticidas , Plaguicidas , Animales , Caspasa 9/metabolismo , Caspasa 9/farmacología , Spodoptera/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Citocromos c/metabolismo , Citocromos c/farmacología , Caspasa 3/metabolismo , Insecticidas/farmacología , Insecticidas/metabolismo , Fungicidas Industriales/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Mitocondrias , Potencial de la Membrana Mitocondrial , Apoptosis , Proliferación Celular , Furocumarinas/farmacología
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