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1.
Opt Lett ; 49(17): 4914-4917, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39207996

RESUMO

We propose a complex-amplitude diffractive processor based on diffractive deep neural networks (D2NNs). By precisely controlling the propagation of an optical field, it can effectively remove the motion blur in numeral images and realize the restoration. Comparative analysis of phase-only, amplitude-only, and complex-amplitude diffractive processor reveals that the complex-amplitude network significantly enhances the performance of the processor and improves the peak signal-to-noise ratio (PSNR) of the images. Appropriate use of complex-amplitude networks contributes to reduce the number of network layers and alleviates alignment difficulties. Due to its fast processing speed and low power consumption, complex-amplitude diffractive processors hold potential applications in various fields including road monitoring, sports photography, satellite imaging, and medical diagnostics.

2.
Opt Lett ; 49(6): 1595-1598, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489459

RESUMO

In the realm of metasurface-based polarimetry, well-known for its remarkable compactness and integration capabilities, previous attempts have been hindered by limitations such as the restricted choices of target polarization states and the inefficient focusing of light. To address these problems, this study introduces and harnesses a novel, to our knowledge, forward-solving model, grounded in the equivalence principle and dyadic Green's function, to inversely optimize the vectorial focusing patterns of metalenses. Leveraging this methodology, we develop and experimentally validate a single multi-foci metalens-based polarimeter, capable of simultaneously separating and concentrating four distinct elliptical polarization states at a wavelength of 10.6 µm. Rigorous experimental evaluations, involving the assessment of 18 scalar polarized beams, reveal an average error of 5.92% and a high contrast ratio of 0.92, which demonstrates the efficacy of the polarimeter. The results underscore the potential of our system in diverse sectors, including military defense, healthcare, and autonomous vehicle technology.

3.
Opt Lett ; 48(20): 5379-5382, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831872

RESUMO

We use a flexible two-photon photopolymerization direct laser writing to fabricate an integrated diffractive lens system on a fiber tip to expand the output beam of the fiber. The results show that the micro-integrated beam expander based on double lenses (axial size of about 100 µm) has a magnification of 5.9 and a loss of 0.062 dB. Subsequently, we demonstrate the fabrication of a spiral phase plate (diffractive optical elements) and micro-lens arrays (refractive optical elements) on an integrated beam expander, and their optical properties are measured and analyzed, respectively. This Letter is an exploration of the future integrated micro-optical systems on an optical fiber tip.

4.
Opt Lett ; 48(7): 1898-1901, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221794

RESUMO

Achromatic metalenses formed using previous design methods face a compromise between diameter, numerical aperture, and working wave band. To address this problem, the authors coat the refractive lens with a dispersive metasurface and numerically demonstrate a centimeter-scale hybrid metalens for the visible band of 440-700 nm. By revisiting the generalized Snell law, a universal design of a chromatic aberration correction metasurface is proposed for a plano-convex lens with arbitrary surface curvatures. A highly precise semi-vector method is also presented for large-scale metasurface simulation. Benefiting from this, the reported hybrid metalens is carefully evaluated and exhibits 81% chromatic aberration suppression, polarization insensitivity, and broadband imaging capacity.

5.
Opt Lett ; 47(24): 6460-6463, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36538462

RESUMO

Zoom metalens doublets, featuring ultra-compactness, strong zoom capability, and CMOS compatibility, exhibit unprecedented advantages over the traditional refractive zoom lens. However, the huge chromatic aberration narrows the working bandwidth, which limits their potential applications in broadband systems. Here, by globally optimizing the phase profiles in the visible, we designed and numerically demonstrated a moiré lens based zoom metalens doublet that can achromatically work in the band of 440-640 nm. Such a doublet can achieve a continuous zoom range from 1× to 10×, while also maintaining a high focusing efficiency up to 86.5% and polarization insensitivity.

6.
Opt Lett ; 46(16): 3881-3884, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388765

RESUMO

For the design of achromatic metalenses, one key challenge is to accurately realize the wavelength dependent phase profile. Because of the demand of tremendous simulations, traditional methods are laborious and time consuming. Here, a novel deep neural network (DNN) is proposed and applied to the achromatic metalens design, which turns complex design processes into regression tasks through fitting the target phase curves. During training, x-y projection pairs are put forward to solve the phase jump problem, and some additional phase curves are manually generated to optimize the DNN performance. To demonstrate the validity of our DNN, two achromatic metalenses in the near-infrared region are designed and simulated. Their average focal length shifts are 2.6% and 1.7%, while their average relative focusing efficiencies reach 59.18% and 77.88%.

7.
Sensors (Basel) ; 21(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34883987

RESUMO

This paper presents a model for estimating the moisture of loess from an image grayscale value. A series of well-controlled air-dry tests were performed on saturated Malan loess, and the moisture content of the loess sample during the desiccation process was automatically recorded while the soil images were continually captured using a photogrammetric device equipped with a CMOS image sensor. By converting the red, green, and blue (RGB) image into a grayscale one, the relationship between the water content and grayscale value, referred to as the water content-gray value characteristic curve (WGCC), was obtained; the impacts of dry density, particle size distribution, and illuminance on WGCC were investigated. It is shown that the grayscale value increases as the water content decreases; based on the rate of increase of grayscale value, the WGCC can be segmented into three stages: slow-rise, rapid-rise, and asymptotically stable stages. The influences that dry density and particle size distribution have on WGCC are dependent on light reflection and transmission, and this dependence is closely related to soil water types and their relative proportion. Besides, the WGCC for a given soil sample is unique if normalized with illuminance. The mechanism behind the three stages of WGCC is discussed in terms of visible light reflection. A mathematical model was proposed to describe WGCC, and the physical meaning of the model parameters was interpreted. The proposed model is validated independently using another six different types of loess samples and is shown to match well the experimental data. The results of this study can provide a reference for the development of non-contact soil moisture monitoring methods as well as relevant sensors and instruments.


Assuntos
Solo , Água , China , Água/análise
8.
J Antimicrob Chemother ; 70(3): 802-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25473027

RESUMO

OBJECTIVES: To define the antifungal susceptibility patterns of the most common non-albicans Candida spp. in China. METHODS: We evaluated the susceptibilities to nine antifungal drugs of Candida parapsilosis species complex, Candida tropicalis, Candida glabrata species complex and Candida krusei isolates from patients with invasive candidiasis at 11 hospitals over 3 years. Isolates were identified by MALDI-TOF MS supplemented by DNA sequencing. MICs were determined by Sensititre YeastOne(TM) using current clinical breakpoints/epidemiological cut-off values to assign susceptibility (or WT), and by CLSI M44-A2 disc diffusion for fluconazole and voriconazole. RESULTS: Of 1072 isolates, 392 (36.6%) were C. parapsilosis species complex. C. tropicalis, C. glabrata species complex and C. krusei comprised 35.4%, 24.3% and 3.7% of the isolates, respectively. Over 99.3% of the isolates were of WT phenotype to amphotericin B and 5-flucytosine. Susceptibility/WT rates to azoles among C. parapsilosis species complex were ≥97.5%. However, 11.6% and 9.5% of C. tropicalis isolates were non-susceptible to fluconazole and voriconazole, respectively (7.1% were resistant to both). Approximately 14.3% of C. glabrata sensu stricto isolates (n = 258) were fluconazole resistant, and 11.6% of C. glabrata sensu stricto isolates were cross-resistant to fluconazole and voriconazole. All C. krusei isolates were susceptible/WT to voriconazole, posaconazole and itraconazole. Overall, 97.7%-100% of isolates were susceptible to caspofungin, micafungin and anidulafungin, but 2.3% of C. glabrata were non-susceptible to anidulafungin. There was no azole/echinocandin co-resistance. Disc diffusion and Sensititre YeastOne(TM) methods showed >95% categorical agreement for fluconazole and voriconazole. CONCLUSIONS: In summary, reduced azole susceptibility was seen among C. tropicalis. Resistance to echinocandins was uncommon.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candidíase Invasiva/microbiologia , Candida/classificação , Candida/isolamento & purificação , Candidíase Invasiva/epidemiologia , China/epidemiologia , Farmacorresistência Fúngica , Monitoramento Epidemiológico , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Estudos Prospectivos , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Int J Mol Med ; 54(6)2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39364745

RESUMO

The early restoration of hemodynamics/reperfusion in acute myocardial infarction (AMI) is an effective therapeutic strategy to reduce sudden death and improve patient prognosis. However, reperfusion induces additional cardiomyocyte damage and cardiac tissue dysfunction. In this context, turmeric­derived curcumin (Cur) has been shown to exhibit a protective effect against myocardial ischemia/reperfusion injury (I/RI). The molecular mechanism of its activity, however, remains unclear. The current study investigated the protective effect of Cur and its molecular mechanism via in vitro experiments. The Cell Counting Kit­8 and lactate dehydrogenase (LDH) assay kit were used to assess the cell viability and cytotoxicity. The contents of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase, glutathione (GSH)/glutathione disulfide (GSSG), total iron, ferrous iron, caspase­3 and reactive oxygen species (ROS) were measured using an appropriate kit. Western blotting was used to detect the expression of relevant proteins. The levels of apoptosis, mitochondrial permeability transition pore (MPTP) opening, and mitochondrial membrane potential (MMP) were detected by flow cytometry. The study findings indicated that anoxia/reoxygenation (A/R) injury significantly decreased cell viability, increased in LDH and caspase­3 activities, induced ferroptosis, increased apoptosis and overactivated autophagy. However, pretreatment with Cur or ferrostatin­1 (Fer­1, a ferroptosis inhibitor) significantly increased A/R­reduced cell viability, SOD, glutathione peroxidase activity, GSH/GSSH ratio and HES1 and glutathione peroxidase 4 protein expression; attenuated A/R­induced LDH, MDA, total iron, ferrous iron, prostaglandin­endoperoxide synthase 2 protein expression and prevented ROS overproduction and MMP loss. In addition, Cur inhibited caspase­3 activity, upregulated the Bcl­2/Bax ratio, reduced apoptotic cell number and inhibited MPTP over­opening. Furthermore, Cur increased P62, LC3II/I, NDUFB8 and UQCRC2 expression and upregulated the p­AMPK/AMPK ratio. However, erastin (a ferroptosis activator), pAD/HES1­short hairpin RNA, rapamycin (an autophagy activator) and Compound C (an AMPK inhibitor) blocked the protective effect of Cur. In conclusion, Cur pretreatment inhibited ferroptosis, autophagy overactivation and oxidative stress; improved mitochondrial dysfunction; maintained energy homeostasis; attenuated apoptosis; and ultimately protected the myocardium from A/R injury via increased HES1 expression.


Assuntos
Apoptose , Autofagia , Curcumina , Ferroptose , Traumatismo por Reperfusão Miocárdica , Fatores de Transcrição HES-1 , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/patologia , Ferroptose/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Curcumina/farmacologia , Fatores de Transcrição HES-1/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos
10.
Int J Mol Med ; 53(5)2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577949

RESUMO

Several studies have shown that berberine (BBR) is effective in protecting against myocardial ischemia­reperfusion injury (MI/RI). However, the precise molecular mechanism remains elusive. The present study observed the mechanism and the safeguarding effect of BBR against hypoxia/reoxygenation (H/R) myocardial injury in H9c2 cells. BBR pretreatment significantly improved the decrease of cell viability, P62 protein, Rho Family GTPase 3 (RhoE) protein, ubiquinone subunit B8 protein, ubiquinol­cytochrome c reductase core protein U, the Bcl­2­associated X protein/B­cell lymphoma 2 ratio, glutathione (GSH) and the GSH/glutathione disulphide (GSSG) ratio induced by H/R, while reducing the increase in lactate dehydrogenase, microtubule­associated protein 1 light 3 protein, caspase­3 activity, reactive oxygen species, GSSG and malonaldehyde caused by H/R. Transmission electron microscopy and LysoTracker Red DND­99 staining results showed that BBR pretreatment inhibited H/R­induced excessive autophagy by mediating RhoE. BBR also inhibited mitochondrial permeability transition, maintained the stability of the mitochondrial membrane potential, reduced the apoptotic rate, and increased the level of caspase­3. However, the protective effects of BBR were attenuated by pAD/RhoE­small hairpin RNA, rapamycin (an autophagy activator) and compound C (an AMP­activated protein kinase inhibitor). These new findings suggested that BBR protects the myocardium from MI/RI by inhibiting excessive autophagy, maintaining mitochondrial function, improving the energy supply and redox homeostasis, and attenuating apoptosis through the RhoE/AMP­activated protein kinase pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Autofagia , Berberina , Traumatismo por Reperfusão Miocárdica , Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Berberina/farmacologia , Caspase 3/metabolismo , Dissulfeto de Glutationa/metabolismo , Isquemia/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/etiologia , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Animais , Ratos
11.
Biomed Pharmacother ; 174: 116542, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574620

RESUMO

Previous studies have demonstrated that the underlying mechanisms of myocardial ischemia/reperfusion injury (MIRI) are complex and involve multiple types of regulatory cell death, including ferroptosis, apoptosis, and autophagy. Thus, we aimed to identify the mechanisms underlying MIRI and validate the protective role of epigallocatechin-3-gallate (EGCG) and its related mechanisms in MIRI. An in vivo and in vitro models of MIRI were constructed. The results showed that pretreatment with EGCG could attenuate MIRI, as indicated by increased cell viability, reduced lactate dehydrogenase (LDH) activity and apoptosis, inhibited iron overload, abnormal lipid metabolism, preserved mitochondrial function, decreased infarct size, maintained cardiac function, decreased reactive oxygen species (ROS) level, and reduced TUNEL-positive cells. Additionally, EGCG pretreatment could attenuate ferroptosis, apoptosis, and autophagy induced by MIRI via upregulating 14-3-3η protein levels. Furthermore, the protective effects of EGCG could be abolished with pAd/14-3-3η-shRNA or Compound C11 (a 14-3-3η inhibitor) but not pAd/NC-shRNA. In conclusion, EGCG pretreatment attenuated ferroptosis, apoptosis, and autophagy by mediating 14-3-3η and protected cardiomyocytes against MIRI.


Assuntos
Proteínas 14-3-3 , Apoptose , Autofagia , Catequina , Catequina/análogos & derivados , Ferroptose , Traumatismo por Reperfusão Miocárdica , Catequina/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Animais , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Proteínas 14-3-3/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Cardiotônicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ratos Sprague-Dawley
12.
Sci Rep ; 14(1): 15246, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956068

RESUMO

This study aimed to explore the effects of peroxisome proliferator-activated receptor α (PPAR-α), a known inhibitor of ferroptosis, in Myocardial ischemia/reperfusion injury (MIRI) and its related mechanisms. In vivo and in vitro MIRI models were established. Our results showed that activation of PPAR-α decreased the size of the myocardial infarct, maintained cardiac function, and decreased the serum contents of creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and Fe2+ in ischemia/reperfusion (I/R)-treated mice. Additionally, the results of H&E staining, DHE staining, TUNEL staining, and transmission electron microscopy demonstrated that activation of PPAR-α inhibited MIRI-induced heart tissue and mitochondrial damage. It was also found that activation of PPAR-α attenuated MIRI-induced ferroptosis as shown by a reduction in malondialdehyde, total iron, and reactive oxygen species (ROS). In vitro experiments showed that intracellular contents of malondialdehyde, total iron, LDH, reactive oxygen species (ROS), lipid ROS, oxidized glutathione disulphide (GSSG), and Fe2+ were reduced by the activation of PPAR-α in H9c2 cells treated with anoxia/reoxygenation (A/R), while the cell viability and GSH were increased after PPAR-α activation. Additionally, changes in protein levels of the ferroptosis marker further confirmed the beneficial effects of PPAR-α activation on MIRI-induced ferroptosis. Moreover, the results of immunofluorescence and dual-luciferase reporter assay revealed that PPAR-α achieved its activity via binding to the 14-3-3η promoter, promoting its expression level. Moreover, the cardioprotective effects of PPAR-α could be canceled by pAd/14-3-3η-shRNA or Compound C11 (14-3-3η inhibitor). In conclusion, our results indicated that ferroptosis plays a key role in aggravating MIRI, and PPAR-α/14-3-3η pathway-mediated ferroptosis and mitochondrial injury might be an effective therapeutic target against MIRI.


Assuntos
Proteínas 14-3-3 , Ferroptose , Traumatismo por Reperfusão Miocárdica , PPAR alfa , Animais , Masculino , Camundongos , Ratos , Proteínas 14-3-3/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Ferroptose/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , PPAR alfa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
13.
Exp Ther Med ; 27(5): 233, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38628660

RESUMO

The present study aimed to elucidate the role of autophagy-related genes (ARGs) in calcific aortic valve disease (CAVD) and their potential interactions with immune infiltration via experimental verification and bioinformatics analysis. A total of three microarray datasets (GSE12644, GSE51472 and GSE77287) were obtained from the Gene Expression Omnibus database, and gene set enrichment analysis was performed to identify the relationship between autophagy and CAVD. After differentially expressed genes and differentially expressed ARGs (DEARGs) were identified using CAVD samples and normal aortic valve samples, a functional analysis was performed, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses, protein-protein interaction network construction, hub gene identification and validation, immune infiltration and drug prediction. The results of the present study indicated a significant relationship between autophagy and CAVD. A total of 46 DEARGs were identified. GO and pathway enrichment analyses revealed the complex roles of DEARGs in regulating CAVD, including multiple gene functions and pathways. A total of 10 hub genes were identified, with three (SPP1, CXCL12 and CXCR4) consistently upregulated in CAVD samples compared with normal aortic valve samples in multiple datasets and experimental validation. Immune infiltration analyses demonstrated significant differences in immune cell proportions between CAVD samples and normal aortic valve samples, thus showing the crucial role of immune infiltration in CAVD development. Furthermore, therapeutic drugs were predicted that could target the identified hub genes, including bisphenol A, resveratrol, progesterone and estradiol. In summary, the present study illuminated the crucial role of autophagy in CAVD development and identified key ARGs as potential therapeutic targets. In addition, the observed immune cell infiltration and predicted autophagy-related drugs suggest promising avenues for future research and novel CAVD treatments.

14.
Front Immunol ; 15: 1335333, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38449872

RESUMO

Background and objective: Macrophages play a crucial and dichotomous role cardiac repair following myocardial ischemia-reperfusion, as they can both facilitate tissue healing and contribute to injury. This duality is intricately linked to environmental factors, and the identification of macrophage subtypes within the context of myocardial ischemia-reperfusion injury (MIRI) may offer insights for the development of more precise intervention strategies. Methods: Specific marker genes were used to identify macrophage subtypes in GSE227088 (mouse single-cell RNA sequencing dataset). Genome Set Enrichment Analysis (GSEA) was further employed to validate the identified LAM subtypes. Trajectory analysis and single-cell regulatory network inference were executed using the R packages Monocle2 and SCENIC, respectively. The conservation of LAM was verified using human ischemic cardiomyopathy heart failure samples from the GSE145154 (human single-cell RNA sequencing dataset). Fluorescent homologous double-labeling experiments were performed to determine the spatial localization of LAM-tagged gene expression in the MIRI mouse model. Results: In this study, single-cell RNA sequencing (scRNA-seq) was employed to investigate the cellular landscape in ischemia-reperfusion injury (IRI). Macrophage subtypes, including a novel Lipid-Associated Macrophage (LAM) subtype characterized by high expression of Spp1, Trem2, and other genes, were identified. Enrichment and Progeny pathway analyses highlighted the distinctive functional role of the SPP1+ LAM subtype, particularly in lipid metabolism and the regulation of the MAPK pathway. Pseudotime analysis revealed the dynamic differentiation of macrophage subtypes during IRI, with the activation of pro-inflammatory pathways in specific clusters. Transcription factor analysis using SCENIC identified key regulators associated with macrophage differentiation. Furthermore, validation in human samples confirmed the presence of SPP1+ LAM. Co-staining experiments provided definitive evidence of LAM marker expression in the infarct zone. These findings shed light on the role of LAM in IRI and its potential as a therapeutic target. Conclusion: In conclusion, the study identifies SPP1+ LAM macrophages in ischemia-reperfusion injury and highlights their potential in cardiac remodeling.


Assuntos
Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Humanos , Animais , Camundongos , Traumatismo por Reperfusão Miocárdica/genética , Genes Reporter , Macrófagos , Lipídeos , Glicoproteínas de Membrana , Receptores Imunológicos
15.
Eur J Pharmacol ; 971: 176524, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38561102

RESUMO

The present study aimed to explore how resveratrol (Res) confers myocardial protection by attenuating ferroptosis. In vivo and in vitro myocardial ischemia/reperfusion injury (MIRI) models were established, with or without Res pretreatment. The results showed that Res pretreatment effectively attenuated MIRI, as evidenced by increased cell viability, reduced lactate dehydrogenase activity, decreased infarct size, and maintained cardiac function. Moreover, Res pretreatment inhibited MIRI-induced ferroptosis, as shown by improved mitochondrial integrity, increased glutathione level, decreased prostaglandin-endoperoxide synthase 2 level, inhibited iron overload, and abnormal lipid peroxidation. Of note, Res pretreatment decreased or increased voltage-dependent anion channel 1/glutathione peroxidase 4 (VDAC1/GPX4) expression, which was increased or decreased via anoxia/reoxygenation (A/R) treatment, respectively. However, the overexpression of VDAC1 via pAd/VDAC1 and knockdown of GPX4 through Si-GPX4 reversed the protective effect of Res in A/R-induced H9c2 cells, whereas the inhibition of GPX4 with RSL3 abolished the protective effect of Res on mice treated with ischemia/reperfusion.Interestingly, knockdown of VDAC1 by Si-VDAC1 promoted the protective effect of Res on A/R-induced H9c2 cells and the regulation of GPX4. Finally, the direct interaction between VDAC1 and GPX4 was determined using co-immunoprecipitation. In conclusion, Res pretreatment could protect the myocardium against MIRI-induced ferroptosis via the VDAC1/GPX4 signaling pathway.


Assuntos
Ferroptose , Traumatismo por Reperfusão Miocárdica , Animais , Camundongos , Miócitos Cardíacos , Resveratrol/farmacologia , Canal de Ânion 1 Dependente de Voltagem , Isquemia , Hipóxia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Reperfusão
16.
Tumour Biol ; 34(3): 1865-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23519840

RESUMO

Gastric cancer is the second leading cause of cancer mortality, but the molecular mechanisms underlying its progression and metastasis remain unclear. CCR7 and Dicer 1 protein expression in 80 gastric adenocarcinomas and 40 peritumoral tissues were measured by immunohistochemical staining. The expression of let-7a miRNA in serum, tumor tissues, and peritumoral tissues was measured by real-time PCR. The role of let-7a in CCR7 protein expression, migration, and invasion of gastric cancer cells was tested in vitro. Dicer 1 protein expression was found to be significantly reduced, whereas CCR7 protein expression was significantly increased in gastric adenocarcinomas compared to peritumoral tissues. The let-7a miRNA levels in the serum and tumor tissues of gastric adenocarcinoma patients were significantly lower than in the serum of healthy controls and peritumoral tissues, respectively. Dicer 1 protein positively correlated with let-7a miRNA level, but negatively correlated with CCR7 protein level in gastric adenocarcinoma. Negative Dicer 1 protein and let-7a miRNA expression and positive CCR7 protein expression significantly correlated with lymph node metastasis, depth of invasion, high clinical TNM stage, and larger tumor size. Let-7a transfection significantly inhibited CCR7 protein expression, migration, and invasion of MNK-45 cells in vitro. High expression of CCR7 protein and low expression of Dicer 1 protein and let-7a miRNA are significantly associated with the metastasis and progression of gastric cancer. High CCR7 protein expression may be caused by the loss of Dicer 1 protein expression and reduced let-7a miRNA level in gastric cancer. The serum let-7a level might be a marker for the diagnosis of gastric cancer.


Assuntos
Adenocarcinoma/patologia , Movimento Celular , Proliferação de Células , RNA Helicases DEAD-box/genética , MicroRNAs/genética , Receptores CCR7/genética , Ribonuclease III/genética , Neoplasias Gástricas/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Western Blotting , Diferenciação Celular , RNA Helicases DEAD-box/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores CCR7/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonuclease III/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
17.
Int J Mol Med ; 52(5)2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37800609

RESUMO

Tanshinone IIA (TSN) extracted from danshen (Salvia miltiorrhiza) could protect cardiomyocytes against myocardial ischemia/reperfusion injury (IRI), however the underlying molecular mechanisms of action remain unclear. The aim of the present study was to identify the protective effects of TSN and its mechanisms of action through in vitro studies. An anoxia/reoxygenation (A/R) injury model was established using H9c2 cells to simulate myocardial IRI in vitro. Before A/R, H9c2 cardiomyoblasts were pretreated with 8 µM TSN or 10 µM ferrostatin­1 (Fer­1) or erastin. The cell counting kit 8 (CCK­8) and lactate dehydrogenase (LDH) assay kit were used to detect the cell viability and cytotoxicity. The levels of total iron, glutathione (GSH), glutathione disulfide (GSSG), malondialdehyde (MDA), ferrous iron, caspase­3 activity, and reactive oxygen species (ROS) were assessed using commercial kit. The levels of mitochondrial membrane potential (MMP), lipid ROS, cell apoptosis, and mitochondrial permeability transition pore (mPTP) opening were detected by flow cytometry. Transmission electron microscopy (TEM) was used to observed the mitochondrial damage. Protein levels were detected by western blot analysis. The interaction between TSN and voltage­dependent anion channel 1 (VDAC1) was evaluated by molecular docking simulation. The results showed that pretreatment with TSN and Fer­1 significantly decreased cell viability, glutathione peroxidase 4 (GPX4) protein and GSH expression and GSH/GSSG ratio and inhibited upregulation of LDH activity, prostaglandin endoperoxide synthase 2 and VDAC1 protein expression, ROS levels, mitochondrial injury and GSSG induced by A/R. TSN also effectively inhibited the damaging effects of erastin treatment. Additionally, TSN increased MMP and Bcl­2/Bax ratio, while decreasing levels of apoptotic cells, activating Caspase­3 and closing the mPTP. These effects were blocked by VDAC1 overexpression and the results of molecular docking simulation studies revealed a direct interaction between TSN and VDAC1. In conclusion, TSN pretreatment effectively attenuated H9c2 cardiomyocyte damage in an A/R injury model and VDAC1­mediated ferroptosis and apoptosis served a vital role in the protective effects of TSN.


Assuntos
Ferroptose , Traumatismo por Reperfusão Miocárdica , Humanos , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Caspase 3/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Dissulfeto de Glutationa/metabolismo , Simulação de Acoplamento Molecular , Miócitos Cardíacos/metabolismo , Apoptose , Ferro/metabolismo
18.
Exp Ther Med ; 26(5): 534, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37869642

RESUMO

Acute myocardial infarction is a life-threatening condition with high mortality and complication rates. Although myocardial reperfusion can preserve ischemic myocardial tissue, it frequently exacerbates tissue injury, a phenomenon known as ischemia-reperfusion injury (IRI). However, the underlying pathological mechanisms of IRI remain to be completely understood. Ferroptosis is a novel type of regulated cell death that is associated with various pathological conditions, including angiocardiopathy. The purpose of this article was to elucidate the possible mechanistic role of ferroptosis in IRI through bioinformatics analysis and experimental validation. Healthy and IRI heart samples were screened for differentially expressed ferroptosis-related genes and functional enrichment analysis was performed to determine the potential crosstalk and pathways involved. A protein-protein interaction network was established for IRI, and 10 hub genes that regulate ferroptosis, including HIF1A, EGFR, HMOX1, and ATF3 were identified. In vitro, an anoxia/reoxygenation (A/R) injury model was established using H9c2 cardiomyoblasts to validate the bioinformatics analysis results, and extensive ferroptosis was detected. A total of 4 key hub genes and 3 key miRNAs were also validated. It was found that IRI was related to the aberrant infiltration of immune cells and the small-molecule drugs that may protect against IRI by preventing ferroptosis were identified. These results provide novel insights into the role of ferroptosis in IRI, which can help identify novel therapeutic targets.

19.
J Inflamm Res ; 16: 995-1015, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923465

RESUMO

Introduction: Sepsis is currently a common condition in emergency and intensive care units, and is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Cardiac dysfunction caused by septic myocardial injury (SMI) is associated with adverse prognosis and has significant economic and human costs. The pathophysiological mechanisms underlying SMI have long been a subject of interest. Recent studies have identified ferroptosis, a form of programmed cell death associated with iron accumulation and lipid peroxidation, as a pathological factor in the development of SMI. However, the current understanding of how ferroptosis functions and regulates in SMI remains limited, particularly in the absence of direct evidence from human heart. Methods: We performed a sequential comprehensive bioinformatics analysis of human sepsis cardiac transcriptome data obtained through the GEO database. The lipopolysaccharide-induced mouse SMI model was used to validate the ferroptosis features and transcriptional expression of key genes. Results: We identified widespread dysregulation of ferroptosis-related genes (FRGs) in SMI based on the human septic heart transcriptomes, deeply explored the underlying biological mechanisms and crosstalks, followed by the identification of key functional modules and hub genes through the construction of protein-protein interaction network. Eight key FRGs that regulate ferroptosis in SMI, including HIF1A, MAPK3, NOX4, PPARA, PTEN, RELA, STAT3 and TP53, were identified, as well as the ferroptosis features. All the key FRGs showed excellent diagnostic capability for SMI, part of them was associated with the prognosis of sepsis patients and the immune infiltration in the septic hearts, and potential ferroptosis-modulating drugs for SMI were predicted based on key FRGs. Conclusion: This study provides human septic heart transcriptome-based evidence and brings new insights into the role of ferroptosis in SMI, which is significant for expanding the understanding of the pathobiological mechanisms of SMI and exploring promising diagnostic and therapeutic targets for SMI.

20.
J Clin Microbiol ; 50(12): 3952-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23035204

RESUMO

We conducted active, laboratory-based surveillance for isolates from patients with invasive infections across China from August 2009 to July 2010. DNA sequencing methods were used to define species, and susceptibility to fluconazole and voriconazole was determined by the Clinical and Laboratory Standards Institute M44-A2 disk diffusion method but using up-to-date clinical breakpoints or epidemiological cutoff values. Candida spp. made up 90.5% of the 814 yeast strains isolated, followed by Cryptococcus neoformans (7.7%) and other non-Candida yeast strains (1.7%). Bloodstream isolates made up 42.9% of the strains, isolates from ascitic fluid made up 22.1%, but pus/tissue specimens yielded yeast strains in <5% of the cases. Among the Candida isolates, Candida albicans was the most common species from specimens other than blood (50.1%) but made up only 23% of the bloodstream isolates (P < 0.001). C. parapsilosis complex species were the most common Candida isolates from blood (33.2%). Uncommon bloodstream yeast strains included Trichosporon spp., C. pelliculosa, and the novel species C. quercitrusa, reported for the first time as a cause of candidemia. Most (>94%) of the isolates of C. albicans, C. tropicalis, and the C. parapsilosis complex were susceptible to fluconazole and voriconazole, as were all of the Trichosporon strains; however, 12.2% of the C. glabrata sensu stricto isolates were fluconazole resistant and 17.8% had non-wild-type susceptibility to voriconazole. Seven C. tropicalis strains were cross-resistant to fluconazole and voriconazole; six were from patients in the same institution. Resistance to fluconazole and voriconazole was seen in 31.9% and 13.3% of the uncommon Candida and non-Candida yeast strains, respectively. Causative species and azole susceptibility varied with the geographic region. This study provided clinically useful data on yeast strains and their antifungal susceptibilities in China.


Assuntos
Antifúngicos/farmacologia , Infecção Hospitalar/microbiologia , Fluconazol/farmacologia , Micoses/microbiologia , Pirimidinas/farmacologia , Triazóis/farmacologia , Leveduras/efeitos dos fármacos , China , Farmacorresistência Fúngica , Monitoramento Epidemiológico , Humanos , Estudos Prospectivos , Voriconazol , Leveduras/classificação , Leveduras/genética , Leveduras/isolamento & purificação
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