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1.
Small ; : e2400985, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693073

RESUMO

Ionic liquids have been widely used to improve the efficiency and stability of perovskite solar cells (PSCs), and are generally believed to passivate defects on the grain boundaries of perovskites. However, few studies have focused on the relevant effects of ionic liquids on intragrain defects in perovskites which have been shown to be critical for the performance of PSCs. In this work, the effect of ionic liquid 1-hexyl-3-methylimidazolium iodide (HMII) on intragrain defects of formamidinium lead iodide (FAPbI3) perovskite is investigated. Abundant {111}c intragrain planar defects in pure FAPbI3 grains are found to be significantly reduced by the addition of the ionic liquid HMII, shown by using ultra-low-dose selected area electron diffraction. As a result, longer charge carrier lifetimes, higher photoluminescence quantum yield, better charge carrier transport properties, lower Urbach energy, and current-voltage hysteresis are achieved, and the champion power conversion efficiency of 24.09% is demonstrated. These observations suggest that ionic liquids significantly improve device performance resulting from the elimination of {111}c intragrain planar defects.

2.
Opt Express ; 31(20): 33679-33703, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859143

RESUMO

All roads lead to Rome. In this article we propose a novel theoretical framework to demonstrate vector beams whose degree of polarization does not change on atmospheric propagation. Inspired by the Fresnel equations, we derive the reflected and refracted field of vector beams propagating through a phase screen by employing the continuity of electromagnetic field. We generalize the conventional split-step beam propagation method by considering the vectorial properties in the vacuum diffraction and the refractive properties of a single phase screen. Based on this vectorial propagation model, we extensively calculate the change of degree of polarization (DOP) of vector beams under different beam parameters and turbulence parameters both in free-space and satellite-mediated links. Our result is that whatever in the free-space or satellite-mediated regime, the change of DOP mainly fluctuates around the order of 10-13 to 10-6, which is almost negligible.

3.
Neurochem Res ; 47(5): 1243-1254, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35084661

RESUMO

Hypoxic-ischemic brain damage (HIBD) is a familiar neurological disorder. Emerging reports manifest that microRNAs (miRs) are related to the progression of HIBD. The goal of this study is to explore the mechanism of miR-192-5p in HIBD via regulation of Yes-associated protein 1 (YAP1)-mediated Hippo signaling pathway. The miR-192-5p, YAP1, and Hippo pathway-related factors Phospho (p)-Triaminoguanidinium azide (TAZ) in hippocampal tissues and neurons were detected. The regulatory relationship between miR-192-5p and YAP1 was verified. Neonatal hypoxic ischemia and oxygen-glucose deprivation (OGD) were used to simulate HIBD in vivo and in vitro. The neurobehavioral impairment, neuronal damage and vascular endothelial growth factor (VEGF) expression of neonatal rats in each group were detected. The viability, apoptosis and VEGF expression of hippocampal neurons in each group were also examined. MiR-192-5p expression was elevated while YAP1 expression was reduced in hippocampal tissues of HIBD rats in vivo and OGD neurons in vitro. MiR-192-5p had a targeting relation with YAP1. Suppressed miR-192-5p or overexpressed YAP1 in HIBD rats alleviated neurobehavioral impairment and neuronal damage, and decreased the expression levels of p-TAZ and VEGF expression in vivo. Reduced miR-192-5p or augmented YAP1 decelerated the neuron apoptosis, decreased the p-TAZ level and VEGF level and promoted cell viability of OGD hippocampal neurons in vitro. The study highlights that inhibited miR-192-5p protects against HIBD via regulation of YAP1 and Hippo signaling pathway, which is beneficial for HIBD treatment.


Assuntos
Hipóxia-Isquemia Encefálica , MicroRNAs , Animais , Animais Recém-Nascidos , Apoptose/fisiologia , Modelos Animais de Doenças , Via de Sinalização Hippo , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , MicroRNAs/metabolismo , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Sinalização YAP
4.
Opt Express ; 29(20): 31078-31098, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615209

RESUMO

Quantum key distribution (QKD) employed orbital angular momentum (OAM) for high-dimensional encoding enhances the system security and information capacity between two communication parties. However, such advantagesare significantly degraded because of the fragility of OAM states in atmospheric turbulence. Unlike previous researches, we first investigate the performance degradation of OAM-based QKD by infinitely long phase screen (ILPS), which offers a feasible way to study how adaptive optics (AO) dynamically corrects the turbulence-induced aberrations in real time. Secondly, considering the failure of AO while encountering phase cuts, we evaluate the quality enhancement of OAM-based QKD under a moderate turbulence strength by AO after implementing the wrapped cuts elimination. Finally, we simulate that, with more realistic considerations; real-time AO can still mitigate the impact of atmospheric turbulence on OAM-based QKD even in the large wind velocity regime.

5.
J Opt Soc Am A Opt Image Sci Vis ; 38(8): 1120-1129, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613305

RESUMO

The recently so-called deviation scale [Phys. Rev. A99, 013828 (2019)PLRAAN1050-294710.1103/PhysRevA.99.013828] bridges the connection between the result of the infinitesimal propagation equation (IPE) prediction and that of the single phase screen (SPS) approximation. Thanks to the multiple phase screen (MPS) approach, in this paper we elaborate the physical meaning of the deviation scale: the spatial accumulation of slight intensity modulation of incident orbital angular momentum (OAM)-carrying beam splits the original vortex into multiple individual vortices with a topological charge (TC) of +1 and regenerates the vortex-antivortex pairs with a TC of +1 and with a TC of -1, leading to a significant deviation between these two different results only when the disruption of this compound effect on the phase distribution of the incident OAM-carrying beam becomes more significant. Other than that, we also show that the appearance of the deviation scale cannot be predicted only by the Rytov variance, which can be predicted through the vortex-splitting ratio of the received optical field alone or with the help of the normalized propagation distance.

6.
IUBMB Life ; 72(5): 1065-1074, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32083808

RESUMO

This study aimed to investigate the renal protective effect of atorvastatin (ATV) on the kidney inflammation induced by calcium oxalate (CaOx) crystals. A cell model of cell-crystal interactions and a rat model of CaOx kidney stone were established. The expressions of TLR4, NF-κB, NLRP3, and cleaved caspase-1 in cells and rat kidney tissues were detected using Western blot, immunohistochemical, and/or immunofluorescence. The concentrations of malondialdehyde (MDA), superoxide dismutase (SOD), reactive oxygen species (ROS) in cells, and lactic acid dehydrogenase (LDH) in the culture medium were measured. The secreted levels of interleukin (IL)-1ß, IL-18, IL-6, and tumor necrosis factor-α (TNF-α) were examined by ELISA. The serum levels of creatinine (CRE) and blood urea nitrogen (BUN) were measured. von Kossa staining was used for the evaluation of renal lens deposition. The CaOx model group showed significantly decreased SOD level; increased concentrations of MDA; ROS and LDH; elevated expressions of TLR4, NF-κB, NLRP3, and cleaved caspase-1; and the elevated release of IL-1ß, IL-18, IL-6, and TNF- α as compared to the control group. The treatment with ATV significantly inhibited the formation of CaOx kidney stone by increasing the level of SOD; downregulating MDA, ROS, and LDH; inhibiting the expressions of TLR4, NF-κB, NLRP3 and cleaved caspase-1; and blocking the secretion of inflammatory cytokines. In addition, the serum levels of CRE and BUN, and the intrarenal crystal deposition were also significantly decreased in ATV-treated rats. In summary, oxidative stress, TLR4/NF-κB, and NLRP3 inflammasome pathways are involved in renal inflammatory responses induced by CaOx crystals. ATV treatment significantly suppressed oxidative stress, inhibited the activation of TLR4/NF-κB and NLRP3 inflammasome pathways, and decreased the release of inflammatory mediators, thereby ameliorating CaOx crystal-induced damage and crystal deposition in HK-2 cells and rat kidney tissues.


Assuntos
Antioxidantes/farmacologia , Atorvastatina/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , NF-kappa B/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Nefrolitíase/tratamento farmacológico , Receptor 4 Toll-Like/genética , Animais , Nitrogênio da Ureia Sanguínea , Caspase 1/genética , Caspase 1/imunologia , Creatinina/sangue , Regulação da Expressão Gênica , Inflamassomos/efeitos dos fármacos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/imunologia , Masculino , Malondialdeído/imunologia , Malondialdeído/metabolismo , NF-kappa B/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Nefrolitíase/induzido quimicamente , Nefrolitíase/genética , Nefrolitíase/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Superóxido Dismutase/genética , Superóxido Dismutase/imunologia , Receptor 4 Toll-Like/imunologia
7.
Nanotechnology ; 30(41): 415401, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31295727

RESUMO

A magnetic skyrmion could be endowed with various dynamic magnetic configurations and behaviors. By artificially generating a gradient magnetic field in a confined nanochannel, we have shown the magnetic dynamics of an isolated skyrmion, achieving the coexistence of moving and breathing modes. Such a phenomenon has been proven to be not only correlated to the gradient strength of a magnetic field, but also depends on the Dzyaloshinskii-Moriya interaction. By increasing the magnetic field gradient up to 0.1 mT nm-1, the skyrmion can effectively overcome the skyrmion Hall effect, and meanwhile generate a breathing mode during the motion process under MFG = 1.0 mT nm-1 and DMI = 2.8 mJ m-3. The present study could provide an alternative approach to regulate the skyrmion at micro/nanoscales by using a gradient magnetic field.

8.
Kidney Blood Press Res ; 44(4): 777-791, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31408871

RESUMO

BACKGROUND: M2 macrophages have important roles in diseases such as tumours, cardiovascular diseases and renal diseases. This study aimed to determine the effects and protective mechanism of M2 macrophages against oxidative stress injury and apoptosis induced by calcium oxalate crystals (CaOx) in renal tubular epithelial cells (HK-2) under coculture conditions. METHODS: THP-1 cells were induced to differentiate into M2 macrophages by using phorbol-12-myristate-13-acetate, IL-4 and IL-13. Morphological features were observed by microscopy. Phenotypic markers were identified by reverse transcription-polymerase chain reaction, Western blot and enzyme-linked immunosorbent assay (ELISA). HK-2 cells were treated with 0.5 mg/mL CaOx crystals and co-cultured with M2 macrophages or apocynin. The viability of HK-2 cells was detected by CCK-8 assay. The lactate dehydrogenase (LDH) activity of HK-2 cells was analysed using a microplate reader. The apoptosis of HK-2 cells was examined by flow cytometry and Hoechst 33258 staining. Reactive oxygen species (ROS) expression and mitochondrial membrane potential in HK-2 cells were detected by a fluorescence microplate reader. Western blot analysis was conducted to detect the expression of p47phox, Bcl-2, cleaved caspase-3, cytochrome c, p38 MAPK, phospho-p38 MAPK, Akt and phospho-Akt. RESULTS: The results of morphology, reverse transcription-polymerase chain reaction, Western blot and ELISA showed that THP-1 cells were successfully polarised to M2 macrophages. The results of co-culture suggested that M2 macrophages or apocynin significantly increased the cell viability and decreased the LDH activity and apoptosis rate after HK-2 cells were challenged with CaOx crystals. The expression of the p47phox protein and the concentration of ROS were reduced, the release of mitochondrial membrane potential and the expression of the Bcl-2 protein were upregulated and the protein expression of cleaved caspase-3 and cytochrome c was downregulated. The expression of the phosphorylated form of p38 MAPK increased. Under coculture conditions with M2 macrophages, the Akt protein of HK-2 cells treated with CaOx crystals was dephosphorylated, but the phosphorylated form of Akt was not reduced by apocynin. CONCLUSIONS: M2 macrophages reduced the oxidative stress injury and apoptosis of HK-2 cells by downregulating the activation of NADPH oxidase, reducing the production of ROS, inhibiting the phosphorylation of p38 MAPK and enhancing the phosphorylation of Akt. We have revealed one of the possible mechanisms by which M2 macrophages reduce the formation of kidney stones.


Assuntos
Apoptose/efeitos dos fármacos , Oxalato de Cálcio/farmacologia , Túbulos Renais/efeitos dos fármacos , Macrófagos/fisiologia , Estresse Oxidativo , Acetofenonas/farmacologia , Antioxidantes/farmacologia , Linhagem Celular , Técnicas de Cocultura , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Cálculos Renais , Túbulos Renais/lesões , Túbulos Renais/patologia , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
Kidney Blood Press Res ; 43(1): 246-255, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29490299

RESUMO

BACKGROUND/AIMS: Nephrolithiasis is a common and frequently occurring disease, its exact pathogenesis is remains unclear. Emerging data suggest that autophagy plays a vital role in the pathophysiological processes of kidney diseases. Therefore, this study was designed to investigate the potential role of autophagy in the formation of calcium oxalate (CaOx) kidney stones in rat model. METHODS: Thirty-two rats were randomly divided into four groups (eight rats/group): untreated control group, stone model group, rapamycin-treated group, chloroquine-treated group. Rat models of CaOx nephrolithiasis was administration of 0.75% ethylene glycol (EG) in their drinking water for 4 weeks. Western blot and transmission electron microscope (TEM) were used to detect the expression of autophagy related protein LC3-II, BECN1 and p62 and autophagic vacuoles respectively. Renal function was evaluated by measuring the levels of serum CRE and BUN. Renal tubular injury markers NGAL and Kim-1 was determined by ELISA kits. Von Kossa staining was used to assess crystal deposits and histological tissue injury. TUNEL staining was employed to assess apoptosis of the renal tubular cell. RESULTS: Compare with the controls, the expression of autophagy related protein LC3-II, BECN1 and number of autophagic vacuoles were increased significantly, whereas the p62 protein level was decreased in the stone model group. The levels of apoptosis, serum CRE and BUN, NGAL and Kim-1 in the stone model group were increased compared with the control group and crystals deposition and renal injury were increased significantly. However, the levels of autophagy, kidney injury and crystal deposition were decreased by chloroquine but increased by rapamycin. CONCLUSION: These findings suggested that rats were administration of ethylene glycol could lead to the formation of CaOx nephrolithiasis and autophagy activation. Inhibiting autophagy could be an effective therapeutic approach for decreasing the formation of nephrolithiasis.


Assuntos
Autofagia/efeitos dos fármacos , Etilenoglicol/farmacologia , Rim/lesões , Nefrolitíase/patologia , Animais , Oxalato de Cálcio , Cloroquina/farmacologia , Cristalização , Cálculos Renais/etiologia , Nefrolitíase/etiologia , Ratos , Sirolimo/farmacologia
10.
Materials (Basel) ; 17(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38591663

RESUMO

The stress distribution in prestressed filament wound components plays a crucial role in determining the quality of these components during their operational lifespan. This article proposes a physical model to analyze the stress and deformation of prestressed wound composite components with arch-shaped sections. Drawing upon the principles of beam theory, we delve into the analysis of prestressed wound components with metal liners featuring arch-shaped sections. Our investigation revealed a noteworthy phenomenon termed the "additional bending moment effect" within prestressed wound components with arch-shaped sections. Furthermore, this study establishes a relationship between this additional bending moment and the external pressure. In addition, a 3D finite element (FE) model for prestressed wound components with arch-shaped sections incorporating metal liners was developed. The model's accuracy was validated through a comparison with prestressed wound experiments, showcasing an error margin of less than 2%. In comparison with prestressed wound components with circular cross-sections under identical load and dimensional parameters, it was observed that prestressed wound components with arch-shaped sections exhibit stress distributions in the arc segments akin to their circular counterparts, with differences not exceeding 5%. Notably, when the ratio of the straight segment length to the inner diameter of the arc segment inner is less than 4, the deformation on the symmetric plane of the arc segment in an arch-shaped component can be effectively considered as the summation of deformations in equivalent-sized arc and straight segments under identical loading conditions. This yields an equivalent physical model and a streamlined analysis and design methodology for describing the deformation characteristics of prestressed wound components with arch-shaped sections.

11.
J Colloid Interface Sci ; 674: 266-278, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38936083

RESUMO

The construction of heterojunctions can reduce the energy barrier for the oxygen evolution reaction (OER), which is crucial for the design of efficient electrocatalysts. A novel OER electrocatalyst, composed of g-C3N4-supported NiFeP spherical nanoclusters, was successfully synthesized using a simple hydrothermal method and a gas-phase precipitation method. Benefiting from its unique spherical nanocluster structure and strong electronic interactions among Ni, Fe, and P, the catalyst exhibited outstanding performance under alkaline conditions, with an overpotential of only 232 mV at a current density of 10 mA cm-2 and a Tafel slope of 103 mV dec-1. Additionally, the electrical resistance of NiFeP/g-C3N4 (Rct = 5.1 Ω) was much lower than that of NiFeP (Rct = 10.8 Ω) and layered g-C3N4 (Rct = 44.8 Ω). The formation of a Schottky barrier heterojunction efficiently reduced electron transfer impedance during the OER process, accelerating the electron transfer from g-C3N4 to NiFeP, enhancing the carrier concentration, and thereby improving the OER activity. Moreover, The robust g-C3N4 chain-mail protects NiFeP from adverse reaction environments, maintaining a balance between catalytic activity and stability. Furthermore, ab initio molecular dynamics (AIMD) and density functional theory (DFT) were conducted to explore the thermal stability and internal electron transfer behavior of the cluster heterojunction structure. This study offers a broader design strategy for the development of transition metal phosphide (TMPs) materials in the oxygen evolution reaction.

12.
Transl Cancer Res ; 12(8): 1980-1991, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37701110

RESUMO

Background: Neuroendocrine neoplasm (NEN) is a group of rare tumors. Among which, gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN) is the most common group. The World Health Organization (WHO) classified these tumors into three different grades (G1, G2, and G3) based on Ki-67 and mitotic rate, and updated the classification in 2019. Several previous studies proved that Ki-67 was related to tumor prognosis, but others still reported that Ki-67 had no predictive value for tumor prognosis. There are different conclusions between studies regarding the correlation between Ki-67 and tumor prognosis, and there is a lack of studies about this correlation of GEP-NENs. Further analysis is still needed to evaluate the prognostic value of Ki-67 in GEP-NENs, to provide reference for clinical decisions. Methods: A total of 303 studies were retrieved that included Ki-67, GEP-NENs, prognosis, survival, and other subject terms and keywords. We excluded studies that did not show complete Ki-67 index, number of patients and 5-year survival data available for meta-analysis, non-cohort studies, articles published before 2000 or not published in English. Fifteen studies were finally included to assess the value of Ki-67 in the prognosis of patients with GEP-NENs using a random-effects model. Results: The cumulative 5-year survival rate for GEP-NEN G1 (Ki-67 ≤2%), G2 (Ki-67 2-20%) and G3 (Ki-67 >20%) was 86%, 65%, 25% respectively. The 5-year survival rate of GEP-NEN G1 (Ki-67 <3%, first revised in WHO classification 2017, redefined WHO classification 2019) and G1 (Ki-67 ≤2%, WHO classification 2010) was 97% and 84% respectively. Conclusions: The overall prognosis of GEP-NENs patients showed a decreasing trend with the increase of Ki-67, which confirmed the significance of Ki-67 index as a prognostic marker for the prognosis of GEP-NENs. Increasing the cut-off value of Ki-67 index for G1 grade from ≤2% to <3% according to WHO classification 2019 did not significantly decrease the 5-year survival rate.

13.
J Oleo Sci ; 71(3): 379-386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35236797

RESUMO

Osteosarcoma is a relatively uncommon tumor that is defined histologically by malignant cells developing osteoid. Osteosarcomas are mesenchymal cell tumors that cause abnormal bone growth. A combination of genetic, epigenetic, and environmental factors leads mesenchymal stem cells to develop into bone precursor cells, resulting in osteosarcoma. Only tumor suppressor genes, such as p53, Rb, RECQL4, BLM, and WRN, have been detected in inherited family illnesses with an OS susceptibility. These genes, in particular, play an essential role in the development of OS in individuals. In this research, core genes responsible for OS were determined using a microarray and systems biology. 234 genes encoding overexpression and down-regulation were identified, among which 60 were considered as key genes, many of which had known roles in bone growth. Transcriptional regulatory networks were developed with this data and subsequently partitioned to define cis-regulatory modules. Results indicate that several OS-specific genes have strongly conserved the clustering of bone-related cis-regulatory modules, thus promoting the hypothesis that a bone-related gene network is essential for understanding OS biology and may play a role in bone contractility and anomalies.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Redes Reguladoras de Genes , Humanos , Osteossarcoma/genética , Osteossarcoma/patologia , Biologia de Sistemas
14.
J Oncol ; 2022: 2514555, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35794987

RESUMO

The aim of this study was to investigate the effect of vestibular disruption on autophagy-related proteins and the tumour-associated pathway P13K/Akt in rat sleep and its hypothalamus tissue and to examine whether catechins trigger tumour autophagy. Healthy adult male rats were randomly selected and divided into the vestibular damage group, the sham operation group, and the control group, with 8 rats in each group. A vestibular damage model was established through penetrating the tympanic membrane of the external auditory canal by injecting sodium p-aminophenylarsonate. The electroencephalogram (EGG) activity was used to record the sleep-wakefulness cycle of rats, and the expression levels of hypothalamic orexin (orexin) mRNA and autophagy proteins were detected. Primary hippocampal neurons were intervened with orexin at different concentrations and at different times to detect cell viability and the expression of autophagy protein and P13K/Akt signal pathway protein. The results showed that compared with the control group and the sham operation group, NREM duration in the vestibular damage group decreased significantly (P < 0.05), while its W time increased significantly (P < 0.05). The expression level of orexin mRNA in the hypothalamus of the vestibular damage group was significantly higher than that of the other two groups (P < 0.05), the expression of autophagy microtubule-related proteins LC3B and Beclin-1 increased significantly (P < 0.05), and the protein expression level of p62 decreased significantly (P < 0.05). After orexin intervention, compared with the control group, the expression of Beclin-1 protein that positively correlated with autophagy decreased significantly (P < 0.05) and the expression of mTOR, PDK1, and Akt protein increased significantly (P < 0.05). Compared with the orexin intervention group, the expression of Beclin-1 and LC3B proteins in cells of the orexin receptor inhibitor (Almorexant) group, the autophagy activator (Rapamycin) group, the orexin + Almorexant group, and the orexin + Rapamycin group increased significantly (P < 0.05), and the expression of mTOR, PDK1, and Akt proteins decreased significantly (P < 0.05). Catechins trigger autophagy in part by regulating the p-Akt/p-mTOR and P13K pathways and by stimulating the MAPK pathway. Catechins initiate apoptosis in common tumour types of hepatocellular carcinoma cells by activating autophagy-related pathways. The conclusion is that vestibular damage can affect the sleep-wakefulness cycle of rats; the level of autophagy in hypothalamic tissue is upregulated and may affect cell proliferation and activity through mTOR-P13K/Akt, which has a certain reference value for tumor formation and provides a basis for the research of insomnia or sleep disorders caused by tumors. Autophagy activation is a key process by which catechins promote apoptosis in tumour cells, providing an avenue for more research on the use of catechins-rich diets for cardiovascular protection in the treatment of tumours.

15.
Front Immunol ; 13: 818625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154136

RESUMO

Calcium oxalate nephrolithiasis is a common and highly recurrent disease in urology; however, its precise pathogenesis is still unknown. Recent research has shown that renal inflammatory injury as a result of the cell-crystal reaction plays a crucial role in the development of calcium oxalate kidney stones. An increasing amount of research have confirmed that inflammation mediated by the cell-crystal reaction can lead to inflammatory injury of renal cells, promote the intracellular expression of NADPH oxidase, induce extensive production of reactive oxygen species, activate NLRP3 inflammasome, discharge a great number of inflammatory factors, trigger inflammatory cascading reactions, promote the aggregation, nucleation and growth process of calcium salt crystals, and ultimately lead to the development of intrarenal crystals and even stones. The renal tubular epithelial cells (RTECs)-crystal reaction, macrophage-crystal reaction, calcifying nanoparticles, endoplasmic reticulum stress, autophagy activation, and other regulatory factors and mechanisms are involved in this process.


Assuntos
Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Nefrolitíase/imunologia , Espécies Reativas de Oxigênio/imunologia , Estresse do Retículo Endoplasmático/imunologia , Células Epiteliais/imunologia , Humanos , Inflamação/imunologia
16.
Oncol Lett ; 22(3): 648, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34386070

RESUMO

Centromere protein F (CENPF) plays a key role in the regulation of the cell cycle. The present study revealed that CENPF was overexpressed in a variety of tumors and associated with the poor prognosis of osteosarcoma. The mRNA expression levels of CENPF were analyzed using the Gene Expression Profiling Interactive Analysis database and the protein levels of CENPF were detected in the specimens from patients with osteosarcoma using immunohistochemistry. Cell proliferation, cell cycle and flow cytometry assays were performed after the transfection of control or CENPF plasmids into osteosarcoma cells. A xenografts assay was used to determine the effects of CENPF on tumor growth in vivo. The results showed that CENPF was upregulated in osteosarcoma tissues and associated with high-grade tumor stage (P=0.023) and intraglandular dissemination (P=0.046). The transfection-induced depletion of CENPF in human osteosarcoma MG-63 and U-2 OS cell lines inhibited cell proliferation, stimulated apoptosis and induced cell cycle arrest. Induced CENPF depletion in MG-63 cells inhibited tumor growth of osteosarcoma cells in mice. These findings suggested that elevated CENPF levels contributed to increased cell proliferation by mediating apoptosis and cell cycle in osteosarcoma. Therefore, CENPF might be a potential biomarker for poor prognosis of osteosarcoma.

17.
Cancer Lett ; 518: 82-93, 2021 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-34153400

RESUMO

Despite HER2-targeted cancer treatments have provided considerable clinical benefits, resistance to HER2-targeted agents will inevitably develop. Targeting non-oncogene vulnerabilities including endoplasmic reticulum (EnR) stress has emerged as an attractive alternative approach to improve the efficacy of existing targeted cancer therapies. In the current study, we find that Melatonin sensitizes HER2-positive breast cancer cells to the dual tyrosine kinase inhibitor Lapatinib in vitro. Mechanistically, Melatonin enhances the cytotoxic effects of Lapatinib through promoting excessive EnR stress-induced unfolded protein response (UPR) and ROS overaccumulation. Consistently, the antioxidant N-acetylcysteine remarkably reverses the effects of the drug combination on ROS production, DNA damage and cytotoxicity. Furthermore, Melatonin significantly enhances the anti-tumor effect of Lapatinib in an HCC1954 xenograft model. Meanwhile, Lapatinib resistant HER2-positive breast cancer cells (LapR) display lower basal expression levels of UPR genes and enhanced tolerance to EnR stress with attenuated response to Brefeldin A and Tunicamycin. Importantly, Melatonin also increases the sensitivity of HCC1954 LapR cells to Lapatinib. Together, our findings highlight the potential utility of Melatonin as an adjuvant in the treatment of primary or therapy resistant HER2-positive breast cancer via EnR stress-mediated mechanisms.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Lapatinib/farmacologia , Melatonina/farmacologia , Receptor ErbB-2/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Nus , Inibidores de Proteínas Quinases/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos
18.
Cell Death Dis ; 12(1): 12, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33414468

RESUMO

High levels of Basic Transcription Factor 3 (BTF3) have been associated with prostate cancer. However, the mechanisms underlying the role of BTF3 as an oncogenic transcription factor in prostate tumorigenesis have not been explored. Herein, we report that BTF3 confers oncogenic activity in prostate cancer cells. Mechanistically, while both BTF3 splicing isoforms (BTF3a and BTF3b) promote cell growth, BTF3b, but not BTF3a, regulates the transcriptional expression of the genes encoding the subunits of Replication Factor C (RFC) family that is involved in DNA replication and damage repair processes. BTF3 knockdown results in decreased expression of RFC genes, and consequently attenuated DNA replication, deficient DNA damage repair, and increased G2/M arrest. Furthermore, knockdown of the RFC3 subunit diminishes the growth advantage and DNA damage repair capability conferred by ectopic overexpression of BTF3b. Importantly, we show that enforced BTF3 overexpression in prostate cancer cells induces substantial accumulation of cisplatin-DNA adducts and render the cells more sensitive to cisplatin treatment both in vitro and in vivo. These findings provide novel insights into the role of BTF3 as an oncogenic transcription factor in prostate cancer and suggest that BTF3 expression levels may serve as a potential biomarker to predict cisplatin treatment response.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/genética , Proteína de Replicação C/metabolismo , Fatores de Transcrição/metabolismo , Proliferação de Células , Humanos , Masculino , Oncogenes , Regulação para Cima
19.
Life Sci ; 244: 117232, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31884097

RESUMO

AIMS: This study was designed to reveal the role and underlying mechanism of excessive autophagy mediated by ERS via the PERK-eIF2α pathway in the apoptosis and formation of CaOx kidney stones. MAIN METHODS: Ethylene glycol (EG) was used to establish a rat model of CaOx kidney stones, and 100 mg/kg of ERS inhibitor 4-phenylbutyric acid (4-PBA) or 60 mg/kg of autophagy inhibitor chloroquine (CQ) was administered daily to the rats. Four weeks after administration, we collected blood and kidney tissues to analyze the occurrence of ERS and autophagy, apoptosis, renal function, renal tubular crystal deposition, and kidney damage, respectively. KEY FINDINGS: We observed that both 4-PBA and CQ treatment significantly inhibited the excessive autophagy and reduced apoptosis as well as decreasing p-PERK and p-eIF2α expressions. Meanwhile, the proportion of kidney weight, contents of creatinine and blood urea nitrogen, excretion of neutrophil gelatinase-associated lipocalin and kidney injury molecule 1, and renal tubular deposition were markedly down-regulated. SIGNIFICANCE: The findings in this study suggested that ERS induced excessive autophagy via the PERK-eIF2α pathway, regulating cell damage and apoptosis. ERS-mediated inhibition of excessive autophagy effectively protected kidney function and prevented the apoptosis and formation of kidney stones.


Assuntos
Injúria Renal Aguda/prevenção & controle , Apoptose , Autofagia , Estresse do Retículo Endoplasmático , Cálculos Renais/prevenção & controle , Túbulos Renais/fisiopatologia , Injúria Renal Aguda/patologia , Animais , Fator de Iniciação 2 em Eucariotos/metabolismo , Cálculos Renais/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , eIF-2 Quinase/metabolismo
20.
Biomed Pharmacother ; 121: 109649, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733571

RESUMO

BACKGROUND: Nephrolithiasis is a common disease in urology, and its pathogenesis is associated with various factors. Recent studies have shown that reactive oxygen species (ROS) can promote autophagy in the formation of kidney stones and exacerbate kidney injury. Endoplasmic reticulum stress (ERS), a key factor in regulating intracellular environmental homeostasis, is also directly related to ROS production. Therefore, this study aimed to investigate the regulatory effect of superoxide dismutase (SOD) on autophagy-ERS response during the formation of calcium oxalate (CaOx) kidney stones in rats. METHODS: Thirty-two rats were randomly divided into four groups (n = 8): normal control group, stone model group, stone model with atorvastatin group, and stone model with diethyldithiocarbamic acid (DETC) group. Rat models of CaOx kidney stones were established by intragastric administration of 0.75 % ethylene glycol for 4 weeks. Kidney/body weight was used to assess renal enlargement. Renal function was assessed by measuring serum SOD, creatinine (CRE), and blood urea nitrogen (BUN) levels. The expression of autophagy-related proteins LC3B and BECN1 was detected through immunohistochemical staining. Meanwhile, the expression of autophagy-ERS response-related proteins LC3B, BECN1, p62, GRP78, and CHOP was detected using Western blot and RT-PCR. Renal tubular injury markers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule 1 (Kim-1) were determined through enzyme-linked immunosorbent assay. The apoptosis of renal tubular cells and the expression of their signature proteins cleaved Caspase-3, Bax and Bcl-2 were detected using Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and Western blot assays, respectively. Crystal deposition and histological tissue injury were assessed through Von Kossa staining. RESULTS: Compared with the control group, the stone model group showed higher kidney/body weight ratio; evidently higher expression of autophagy-ERS response- and apoptosis-related proteins LC3B, BECN1, GRP78, CHOP, Bax and cleaved Caspase-3; and lower levels of p62, bcl-2 protein, and SOD. The stone model group also showed higher levels of apoptosis, serum CRE, BUN, NGAL, and Kim-1, as well as considerably greater crystal deposition and renal injury, than the control group. Atorvastatin reduced the levels of autophagy-ERS response, kidney injury, and crystal deposition, but they were increased by DETC. CONCLUSION: Enhanced SOD activity can protect the kidneys by reducing autophagy-ERS response and CaOx kidney stone formation. Atorvastatin may be a new option for the prevention and treatment of nephrolithiasis.


Assuntos
Autofagia/fisiologia , Oxalato de Cálcio/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Cálculos Renais/metabolismo , Cálculos Renais/fisiopatologia , Túbulos Renais/fisiopatologia , Superóxido Dismutase/metabolismo , Animais , Apoptose/fisiologia , Proteína 5 Relacionada à Autofagia/metabolismo , Nitrogênio da Ureia Sanguínea , Creatinina/metabolismo , Túbulos Renais/metabolismo , Masculino , Nefrolitíase/metabolismo , Nefrolitíase/fisiopatologia , Ratos , Ratos Sprague-Dawley
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