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1.
Chem Biol Interact ; 390: 110877, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38286393

RESUMO

Osteoarthritis (OA) is a progressive age-related disease characterised by pathological changes in the synovium, articular cartilage, and subchondral bone, significantly reducing the patients' quality of life. This study investigated the role of glucocorticoids, specifically dexamethasone, in OA progression, with a particular focus on their effects on chondrocytes. Although glucocorticoids are commonly used for OA pain relief, our research demonstrated that high concentrations of dexamethasone may accelerate OA progression by enhancing the ability of reactive oxygen species to inhibit chondrocyte autophagy, resulting in cell death and accelerated cartilage degeneration. Despite reports on the acceleration of pathogenesis and cartilage damage in some patients of OA taking corticosteroids, the mechanism behind the same has not been investigated. This necessitates an investigation of the concentration-dependent changes in the cartilage cells upon dexamethasone administration. In addition, the protective effect of PPAR γ on chondrocytes can prevent the decrease in chondrocyte autophagy and delay cartilage degeneration. Therefore, our study suggests that the therapeutic use of glucocorticoids in OA treatment should be more nuanced considering their potential detrimental effects. Future investigations should focus on the mechanisms underlying the glucocorticoid-mediated modulation of cell death processes, which could provide insights into new therapeutic strategies for OA treatment.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Glucocorticoides/farmacologia , Condrócitos , PPAR gama/metabolismo , Piroptose , Qualidade de Vida , Estresse Oxidativo , Osteoartrite/induzido quimicamente , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Cartilagem Articular/metabolismo , Autofagia , Dexametasona/farmacologia
2.
Environ Pollut ; 344: 123314, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218542

RESUMO

Despite their use as substitutes for perfluorooctanoic acid, the potential toxicities of hexafluoropropylene oxide dimer acid (HFPO-DA, commercial name: GenX) and its analogs (PFDMOHxA, PFDMO2HpA, and PFDMO2OA) remain poorly understood. To assess the hepatotoxicity of these chemicals on females, each chemical was orally administered to female C57BL/6 mice at the dosage of 0.5 mg/kg/d for 28 d. The contribution of peroxisome proliferator-activated receptors (PPARα and γ) and other nuclear receptors involving in these toxic effects of GenX and its analogs were identified by employing two PPAR knockout mice (PPARα-/- and PPARγΔHep) in this study. Results showed that the hepatotoxicity of these chemicals increased in the order of GenX < PFDMOHxA < PFDMO2HpA < PFDMO2OA. The increases of relative liver weight and liver injury markers were significantly much lower in PPARα-/- mice than in PPARα+/+ mice after GenX analog exposure, while no significant differences were observed between PPARγΔHep and its corresponding wildtype groups (PPARγF/F mice), indicating that GenX analog induce hepatotoxicity mainly via PPARα instead of PPARγ. The PPARα-dependent complement pathways were inhibited in PFDMO2HpA and PFDMO2OA exposed PPARα+/+ mice, which might be responsible for the observed liver inflammation. In PPARα-/- mice, hepatomegaly and increased liver lipid content were observed in PFDMO2HpA and PFDMO2OA treated groups. The activated pregnane X receptor (PXR) and constitutive activated receptor (CAR) pathways in the liver of PPARα-/- mice, which were highlighted by bioinformatics analysis, provided a reasonable explanation for hepatomegaly in the absence of PPARα. Our results indicate that GenX analogs could induce more serious hepatotoxicity than GenX whether there is a PPARα receptor or not. These chemicals, especially PFDMO2HpA and PFDMO2OA, may not be appropriate PFOA alternatives.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Fluorocarbonos , Propionatos , Camundongos , Feminino , Animais , Hepatomegalia/induzido quimicamente , PPAR alfa/genética , PPAR alfa/metabolismo , PPAR gama/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Fluorocarbonos/toxicidade , Fluorocarbonos/metabolismo , Camundongos Knockout , Doença Hepática Induzida por Substâncias e Drogas/genética
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 193-199, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32220187

RESUMO

OBJECTIVE: To investigate the effect of exogenous Apelin on pulmonary artery hypertension (PAH) and its related mechanism. METHODS: 26 male SD rats were randomly divided into Control group ( n=6), Model group ( n=10) and Intervention group ( n=10). The rat model of PAH was established by left pneumonectomy combined with monocrotaline injection (PE+MCT) in the Model group and the Intervention group, while the Control group rats were opened chest cavity and injected the same amount of normal saline. From the 2nd week after operation, the Intervention group was intraperitoneally injected with 10 nmol/(kg·d) Apelin-13 for 3 weeks, while the Control group and Model group were injected the same volume of normal saline. The mean pulmonary arterial pressure (mPAP) was measured and the right ventricular hypertrophy index ( RVHI) was calculated in all three groups of rats at the 5th week after operation. The pulmonary tissue HE staining was performed to observe the pulmonary tissue and pulmonary vascular morphology. Protein LC3 was detected by immunofluorescence staining of lung tissues, the mRNA expression level of P62 and Beclin-1 in lung tissues was measured by RT-PCR, and the protein expressions of LC3, LC3-Ⅱ/LC3-Ⅰ, P62 and Beclin-1 in lung tissues were measured by Western blot. RESULTS: Compared with the Control group, the Model group showed increased mPAP and RVHI ( P<0.05), disordered pulmonary tissue structure and thicker pulmonary vascular wall. In Model group rats, expression of LC3 protein and LC3-Ⅱ/LC3-Ⅰ increased in lung tissues, and the expression of Beclin-1 mRNA and the Beclin-1 protein also increased in lung tissues, while the level of P62 mRNA and the expression of P62 protein decreased ( P<0.05). After Apelin-13 intervention, the above indexes were all improved ( P<0.05, compared with the Model group). CONCLUSION: Exogenous Apelin has a certain preventive and therapeutic effect on the formation of PAH, and the mechanism may be related to its inhibition effect on autophagy.


Assuntos
Apelina/farmacologia , Autofagia , Hipertensão Pulmonar , Animais , Autofagia/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/prevenção & controle , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Artéria Pulmonar , Ratos , Ratos Sprague-Dawley
4.
Med Hypotheses ; 132: 109233, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31606702

RESUMO

The guidelines for cardiopulmonary resuscitation (CPR) in pediatric advanced life support suggest that midazolam is the preferred agent for sedation in patients with mild hypothermia, whereas children with cardiac arrest (CA) are at a crucial stage regarding their immature nervous system. Studies have shown that midazolam may have a detrimental effect on the developmental of the pediatric nervous system. Our previous study found that midazolam induced neuronal damage after CPR in young rats. It is speculated that: midazolam causes the potential injury of neurons by inhibiting mitochondrial autophagy expression and is an important factor for the poor prognosis in children after successful CPR. This project intends to adopt the modified asphyxiant CPR model in juvenile rats. Survival rate, neurological function and histopathological changes were evaluated to determine the protective effects of appropriate sedation depth on cerebral ischemia-reperfusion injury in juvenile rats after CPR. Combined with cell biology and molecular biology related technologies, the mechanism by which the mitochondrial pinkl-parkin signaling pathway induces autophagy to inhibit neuronal apoptosis may be key factor in the protective effects of sedation depth on the brain. The aim of this study is to provide experimental evidence and elucidate the mechanisms of improvement of cerebral ischemia-reperfusion injury by sedation depth in children after successful CPR and to lay a theoretical and experimental basis for clinical treatment.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca/terapia , Hipnóticos e Sedativos/uso terapêutico , Hipotermia Induzida/métodos , Midazolam/uso terapêutico , Ubiquitina-Proteína Ligases/genética , Animais , Apoptose , Encéfalo , Criança , Modelos Animais de Doenças , Eletroencefalografia , Fentanila/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Cardiovasculares , Sistema Nervoso/efeitos dos fármacos , Neurônios/metabolismo , Pediatria , Prognóstico , Ratos , Traumatismo por Reperfusão , Transdução de Sinais
5.
ACS Appl Mater Interfaces ; 10(6): 5519-5526, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29345900

RESUMO

There is a great deal of interest in developing battery systems that can exhibit self-healing behavior, thus enhancing cyclability and stability. Given that gallium (Ga) is a metal that melts near room temperature, we wanted to test if it could be employed as a self-healing anode material for lithium-ion batteries (LIBs). However, Ga nanoparticles (NPs), when directly applied, tended to aggregate upon charge/discharge cycling. To address this issue, we employed carbon-coated Ga2O3 NPs as an alternative. By controlling the pH of the precursor solution, highly dispersed and ultrafine Ga2O3 NPs, embedded in carbon shells, could be synthesized through a hydrothermal carbonization method. The particle size of the Ga2O3 NPs was 2.6 nm, with an extremely narrow size distribution, as determined by high-resolution transmission electron microscopy and Brunauer-Emmett-Teller measurements. A lithium-ion battery anode based on this material exhibited stable charging and discharging, with a capacity of 721 mAh/g after 200 cycles. The high cyclability is due to not only the protective effects of the carbon shell but also the formation of Ga0 during the lithiation process, as indicated by operando X-ray absorption near-edge spectroscopy.

6.
Exp Ther Med ; 14(5): 4767-4772, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29201178

RESUMO

Pain subsequent to non-cardiac surgery may affect the endothelial function, which in turn contributes to myocardial injury (MI). The present study examined whether effective pain control is able to improve the postoperative endothelial function. Patients (n=160) undergoing laparoscopic cholecystectomy were randomly assigned into two groups, treated with tramadol analgesic or saline (placebo) following surgery. On preoperative day 1 (baseline) and postoperatively at 2 h, 1 day and 5 days, pain was assessed on a visual analogue scale (VAS), and B-mode ultrasound was used to measure brachial endothelium-dependent flow-mediated dilation (FMD) and nitroglycerin-induced dilation. At 2 h postoperatively, the FMD in the two groups was significantly lower compared with that at the other three time points (P≤0.005), while VAS was significantly higher (P<0.05). Patients in the tramadol group presented significantly reduced VAS values in comparison with those in the placebo group at 2 h and 1 day postoperatively (P=0.013 and 0.031, respectively), as well as significantly higher FMD at 2 h (6.7±1.5 vs. 6.0±1.7%; P=0.001) and 1 day postoperatively (7.3±1.3 vs. 6.9±1.4%; P=0.03). A VAS score of <5 was independently associated with postoperative FMD of ≥7 (odds ratio, 2.5; 95% confidence interval, 1.0-6.0; P=0.047). Backward multivariate linear regression also demonstrated that FMD was independently correlated with age and VAS score (B=-1.403, P=0.011; B=-0.579, P=0.003). The response to nitroglycerin-induced dilation remained stable in all patients at baseline and at all postoperative time points. In conclusion, analgesic treatment may improve the arterial endothelial function following non-cardiac surgery, which may help prevent postoperative MI.

7.
Clin Dev Immunol ; 2013: 160491, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23935646

RESUMO

Sjogren's syndrome (SS) is a systemic, autoimmune disorder characterized by salivary insufficiency and lymphocytic infiltration of the exocrine glands. Even though the mechanism of its pathology and progression has been researched ever since its discovery, the roles of different parts of immune system remain inconclusive. There is no straightforward and simple theory for the pathogenesis and diagnosis of Sjogren's syndrome because of the multiple kinds and functions of autoantibodies, changing proportion of different T-lymphocyte subsets with the progression of disease, unsuspected abilities of B lymphocytes discovered recently, crosstalk between cytokines connecting the factors mentioned previously, and genetic predisposition that contributes to the initiation of this disease. On the other hand, the number of significant reports and open-label studies of B-cell depletion therapy showing clinical efficacy in sjogren's syndrome has continued to accumulate, which provides a promising future for the patients. In a word, further elucidation of the role of different components of the immune system will open avenues for better diagnosis and treatment of SS, whose current management is still mainly supportive.


Assuntos
Síndrome de Sjogren/imunologia , Autoanticorpos/genética , Autoanticorpos/imunologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Humanos , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/genética , Síndrome de Sjogren/terapia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(4): 1028-31, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22715778

RESUMO

Based on the characteristic of high speed line scanning for CCD in transient spectrum detection, a method of transient spectrum detection with array CCD is presented. The high speed line scanning with array CCD was realized by changing the mode of charge transfer. In order to explore the feasibility of this method, a fast detection system of single point based on linear CCD was designed and fabricated. Seven different LED pulses were measured when the system worked at fast detection mode of single point and normal mode respectively. The results demonstrate that the method of fast detection of single point based on linear CCD is feasible, and the rate of single point detection reaches up to 20 MHz. Thus, in theory, it was proved that transient spectrum detection with array CCD by changing the mode of charge transfer is also feasible.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 3060-3, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242517

RESUMO

Based on the spectral characteristic of the detonation temperature, the present paper presents a measurement system of transient multi-wavelength pyrometry with the theory of multi-wavelength thermometry. The FPGA was applied as the hardware developing platform and the high-speed linear CCD was utilized. Each module was controlled by FPGA to achieve the process of real-time data acquisition, storage and transmission. Using the multiple regression analysis method, the dynamic spectral waveforms were calculated. The two laser spectral lines, 630 and 532 nm, were used to calibrate the corresponding pixel sequence numbers and the No. 175 and No. 270 were confirmed. In this paper, the halide tungsten light was measured. The results show that the system can sample continuous spectrum signal at several different times; the CCD can stably work with 40 MHz clock and the frame scanning frequency can achieve 73 kHz.

10.
Huan Jing Ke Xue ; 30(11): 3269-75, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20063739

RESUMO

In the present study, 16 polycyclic aromatic hydrocarbons (PAHs) in the surface sediment from Beijiang River in China were quantitatively determined by GC/MS. The concentration of PAHs varied from 38.2 to 6470 ng x g(-1) dry weight, with average 1071 ng x g(-1), which was in moderate level compared with other rivers in Pear River Basin. The PAHs distribution in Bejiang River was obviously affected by point source emissions. The high PAHs concentrations of 6470 ng x g(-1) and 4 470 ng x g(-1) were found at the outfalls of Shaoye and the Shakou town, respectively, where PAHs probably derived from local mining/smelting and related industrial actives. The ecological risk of surface sediment in Beijiang River was assessed with the methods of sediment quality guidelines (SQGs), sediment quality standards (SQSs) and contamination factors (CFs) . The result shows that the adverse biological toxicity effect might occasionally happen in more than half of sampling stations. By comparison with the background area, the contamination degrees of PAHs in 20 sampling stations were at very high level, which should arrest the local governments' attentions. The highest ecological risk areas occurred at the outfalls of Shaoye and the Shakou town in which the ecological risks derived from PAHs were within between probable effect level (PEL) and frequent effect level (FEL). The future research was suggested mainly focusing on the status of benthos, sources of pollutants and ways to control pollution in high-risk areas.


Assuntos
Ecossistema , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Medição de Risco
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