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1.
ACS Appl Mater Interfaces ; 16(24): 31067-31075, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38859577

RESUMO

Although organic-inorganic hybrid one-dimensional (1D) lead halide postperovskites (LHPPs) have been reported to show white luminescence and tunable photoluminescence quantum yield (PLQY), their structure-property relationships are not fully understood. Here, we used Mn2+ to test the doping effect on the luminescence of two 1D-LHPPs compounds, namely, {TETA[Pb2Br6]}n 1 and {TETA[Pb2Cl6]}n 2, where TETA = triethylenetetrammonium. We found the pristine compounds show yellowish (551 nm) and bluish (447 nm) emission for 1 and 2, respectively, nanosecond excitation lifetimes (4.17 ns for 1 and 2.29 ns for 2) and low PLQYs (4.65 and 3.57% for 1 and 2, respectively). By fine-doping the Mn2+ ions to ca. 8% the PLQYs for 1 and 2 are maximized to 24 and 25% for 1 and 2, respectively. Upon the increasing Mn2+ dopant, the emission wavelengths can also vary gradually from 551 to 615 nm and from 447 to 660 nm for 1 and 2, respectively, covering almost the whole visible-light range, and the excitation lifetimes are enhanced to microseconds (0.77 µs for 1 and 0.39 µs for 2), owing to the more spin-forbidden d-d transition (4T1-6A1) component from the Mn2+ ions present in the photoluminescence spectra. Moreover, these Mn2+-doped 1D-LHPPs demonstrate high structural and optical stability in humid and high-temperature environments. Hence, such doped materials can be fabricated into a UV-pumped white light-emitting diode, rendering the potential application for solid-state lighting and display systems.

2.
Opt Lett ; 49(10): 2757-2760, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748154

RESUMO

Optical camera communication (OCC) has attracted increased attention for its inherent security advantage. However, there still exists the risk of eavesdropping on the broadcasting channel of OCC. To achieve confidential communication, we propose the confidentiality-interference dual light-emitting diode (LED) communication (CIDLC) scheme at the transmitter (TX) and elimination of interference (EI) scheme at the receiver (RX). Meanwhile, interference signals refer to the bit shift of confidential signals. Further, we propose the two-dimensional pilot-aided channel estimation (2D-PACE) scheme to enhance the reliability of multiple-input multiple-output (MIMO) OCC. Experiment results validate the effectiveness of our schemes, which guarantee confidentiality while performing well at a 2 m non-line-of-sight (NLOS) distance. Finally, the communication-illumination integration OCC is constructed via the energy equalization coding (EEC) scheme.

3.
BMC Med Imaging ; 24(1): 124, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802736

RESUMO

BACKGROUND: The prevalence of hypertensive heart disease (HHD) is high and there is currently no easy way to detect early HHD. Explore the application of radiomics using cardiac magnetic resonance (CMR) non-enhanced cine sequences in diagnosing HHD and latent cardiac changes caused by hypertension. METHODS: 132 patients who underwent CMR scanning were divided into groups: HHD (42), hypertension with normal cardiac structure and function (HWN) group (46), and normal control (NOR) group (44). Myocardial regions of the end-diastolic (ED) and end-systolic (ES) phases of the CMR short-axis cine sequence images were segmented into regions of interest (ROI). Three feature subsets (ED, ES, and ED combined with ES) were established after radiomic least absolute shrinkage and selection operator feature selection. Nine radiomic models were built using random forest (RF), support vector machine (SVM), and naive Bayes. Model performance was analyzed using receiver operating characteristic curves, and metrics like accuracy, area under the curve (AUC), precision, recall, and specificity. RESULTS: The feature subsets included first-order, shape, and texture features. SVM of ED combined with ES achieved the highest accuracy (0.833), with a macro-average AUC of 0.941. AUCs for HHD, HWN, and NOR identification were 0.967, 0.876, and 0.963, respectively. Precisions were 0.972, 0.740, and 0.826; recalls were 0.833, 0.804, and 0.863, respectively; and specificities were 0.989, 0.863, and 0.909, respectively. CONCLUSIONS: Radiomics technology using CMR non-enhanced cine sequences can detect early cardiac changes due to hypertension. It holds promise for future use in screening for latent cardiac damage in early HHD.


Assuntos
Diagnóstico Precoce , Hipertensão , Imagem Cinética por Ressonância Magnética , Humanos , Feminino , Masculino , Imagem Cinética por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Hipertensão/diagnóstico por imagem , Hipertensão/complicações , Máquina de Vetores de Suporte , Cardiopatias/diagnóstico por imagem , Idoso , Adulto , Teorema de Bayes , Curva ROC , Interpretação de Imagem Assistida por Computador/métodos , Radiômica
4.
Org Lett ; 26(20): 4400-4405, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38735050

RESUMO

An enantioselective Pd-catalyzed intramolecular desymmetrizing cycloisomerization of N-(cyclopent-3-en-1-yl)propiolamides has been developed by employing a new chiral phosphoramidite ligand. A series of structurally unique bridged azabicycles are achieved in moderate to excellent yields with good E/Z selectivity and high enantioselectivity. Synthetic transformations are conducted to demonstrate the practical utility of this reaction.

5.
Org Lett ; 26(12): 2359-2364, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38488270

RESUMO

A palladium-catalyzed dearomative diarylation of C2-deuterated or C2-nonsubstituted indoles through domino Heck/Suzuki coupling is established. Relying on electron-deficient phosphite ligand, side reactions including intermolecular Suzuki coupling and intramolecular C-D/H arylation are inhibited and a wide range of 2,3-diarylated indolines bearing vicinal tertiary stereocenters including deuterated ones are afforded in moderate to excellent yields (up to 94%) and excellent diastereoselectivities (>20:1). The catalyst loading can be lowered to 0.02 mol % at elevated temperature.

6.
Sci Rep ; 14(1): 7532, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553536

RESUMO

This study investigates the Tip Clearance Cavitation (TCC) characteristics of three different Tip Clearances (TC) (0.4, 0.6, 0.8) and five inlet negative pressure conditions Pj = (- 20-60)kPa to improve the reliability of the aerospace high-speed centrifugal pump during in-orbit operation, based on the premise of good agreement between the TC 0.6 test curve and the simulation performance curve. Under negative pressure and high-speed conditions, the variation gradient of cavitation characteristics with various inlet negative pressures is non-linear and has a sudden change, but the trend becomes stable after the inlet negative pressure drops to a certain stage. The tip clearance cavitation characteristics vary from the blade surface cavitation characteristics due to the difference in forces on both sides. This study is a proper starting point for the design of aerospace power pumps.

7.
Proc Natl Acad Sci U S A ; 121(14): e2315982121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38536757

RESUMO

Throughout evolution, arboviruses have developed various strategies to counteract the host's innate immune defenses to maintain persistent transmission. Recent studies have shown that, in addition to bacteria and fungi, the innate Toll-Dorsal immune system also plays an essential role in preventing viral infections in invertebrates. However, whether the classical Toll immune pathway is involved in maintaining the homeostatic process to ensure the persistent and propagative transmission of arboviruses in insect vectors remain unclear. In this study, we revealed that the transcription factor Dorsal is actively involved in the antiviral defense of an insect vector (Laodelphax striatellus) by regulating the target gene, zinc finger protein 708 (LsZN708), which mediates downstream immune-related effectors against infection with the plant virus (Rice stripe virus, RSV). In contrast, an antidefense strategy involving the use of the nonstructural-protein (NS4) to antagonize host antiviral defense through competitive binding to Dorsal from the MSK2 kinase was employed by RSV; this competitive binding inhibited Dorsal phosphorylation and reduced the antiviral response of the host insect. Our study revealed the molecular mechanism through which Toll-Dorsal-ZN708 mediates the maintenance of an arbovirus homeostasis in insect vectors. Specifically, ZN708 is a newly documented zinc finger protein targeted by Dorsal that mediates the downstream antiviral response. This study will contribute to our understanding of the successful transmission and spread of arboviruses in plant or invertebrate hosts.


Assuntos
Arbovírus , Hemípteros , Oryza , Tenuivirus , Animais , Arbovírus/genética , Hemípteros/fisiologia , Tenuivirus/fisiologia , Insetos Vetores , Antivirais/metabolismo , Oryza/genética , Doenças das Plantas
8.
ACS Appl Mater Interfaces ; 16(5): 5769-5778, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38276961

RESUMO

Lead-free hybrid double perovskite iodides (HDPIs) have piqued increasing research interest due to their environmental friendliness and high stability. However, such antimony-based HDPIs with strong photocurrent response are currently very limited. Here, we successfully design and construct five Ag(I)-Sb(III)-based HDPIs using two types of cyclic aliphatic amines as A-site templates. Interestingly, these Ag(I)-Sb(III) HDPIs exhibit relatively narrow band gaps, preferred orientation, and high stability after being processed into thin films on the indium tin oxide (ITO) substrate. Notably, under illuminations of a xenon lamp, all HDPIs exhibit considerable photocurrent responses, reaching a maximum difference of 17 µA·cm-2 for ASI 1, which is the highest among lead-free halogen-based organic-inorganic hybrid compounds to date. Combining the considerable photocurrents and the high stability, the optoelectronic applications of two-dimensional Ag(I)-Sb(III) HDPIs can be expected.

9.
Front Bioeng Biotechnol ; 11: 1111866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970621

RESUMO

Early, efficient and sensitive detection of serum markers in cervical cancer is very important for the treatment and prognosis to cervical cancer patients. In this paper, a SERS platform based on surface enhanced Raman scattering technology was proposed to quantitatively detect superoxide dismutase in serum of cervical cancer patients. Au-Ag nanoboxs array was made by oil-water interface self-assembly method as the trapping substrate. The single-layer Au-AgNBs array was verified by SERS for possessing excellent uniformity, selectivity and reproducibility. 4-aminothiophenol (4-ATP) was used as Raman signal molecule, it will be oxidized to dithiol azobenzene under the surface catalytic reaction with the condition of PH = 9 and laser irradiation. The quantitative detection of SOD could be achieved by calculating the change of characteristic peak ratio. When the concentration was from 10 U mL-1-160 U mL-1, the concentration of SOD could be accurately and quantitatively detected in human serum. The whole test was completed within 20 min and the limit of quantitation was 10 U mL-1. In addition, serum samples from the cervical cancer, the cervical intraepithelial neoplasia and healthy people were tested by the platform and the results were consistent with those of ELISA. The platform has great potential as a tool for early clinical screening of cervical cancer in the future.

10.
Nanoscale ; 15(11): 5265-5273, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36804644

RESUMO

Stable lead-free hybrid halide double perovskites have sparked widespread interest as a new kind of photoelectric material. Herein, for the first time, we successfully incorporated copper(I) and antimony(III) into two two-dimensional (2D) hybrid bimetallic double perovskite iodides, namely (NH3C6H11)4CuSbI8·H2O (CuSbI-1) and (NH3C6H10NH3)2CuSbI8·0.5H2O (CuSbI-2), using cyclohexylamine and 1,4-cyclohexanediamine as organic components. The band gaps for CuSbI-1 and CuSbI-2 were determined to be 2.22(2) eV and 2.21(2) eV, respectively. Furthermore, these two layered perovskites were readily dissolved in an organic solvent (1 mL DMF can dissolve 1 g sample for each compound) and could form smooth, pinhole-free, and uniform thin films through a facile spin-coating method. Photocurrent experiments with xenon lamp irradiation revealed the obvious photoelectric responses for both 2D double perovskites. The ratio of the photocurrent to the dark current (Ilight/Idark) for CuSbI-1 and CuSbI-2 is about 23 and 10, respectively, further suggesting their potential to be applied as light harvesters or light detectors. More importantly, these 2D double perovskite iodides show high moisture and thermal stabilities, indicating their potential for optoelectronic applications.

11.
Materials (Basel) ; 15(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499900

RESUMO

The microstructural evolution of SK85 pearlitic steel cold-rolled up to a 90% rolling reduction was characterized by scanning electron microscopy with electron backscattered diffraction (EBSD) and X-ray diffraction (XRD). SK85 steel exhibits excellent cold rolling performance. The interlamellar spacing of pearlite is refined obviously and a tensile strength of 2318 MPa can be reached for SK85 steel after 90% rolling reduction, an increase of 83% from 1264 MPa before rolling. The EBSD observation indicates that the {001} <110> texture becomes pronounced at a 90% rolling reduction in cold-rolled Sk85 steel. A propagation and multiplication of dislocations occur during rolling as the kernel average misorientation (KAM) angles significantly increase from 0.72° to 2.11°. The XRD analysis reveals that bcc ferrite is transformed into a bct structure at a 90% rolling reduction. The strengthening mechanism was discussed.

12.
Zhongguo Gu Shang ; 35(11): 1097-103, 2022 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-36415199

RESUMO

OBJECTIVE: To study the effects and mechanisms of miR-181a-5p on the proliferation, cycle and migration of HOS osteosarcoma cells. METHODS: Real-time quantitative PCR was used to detect the expression of miR-181a-5p and HOXB4 in osteoblast hFOB1.19 cell line and osteosarcoma cell lines (HOS, U2OS, MG63). miR-181a-5p mimics and miR-181a-5p inhibitors were respectively transfected into HOS cells by Lipofectamine 2000, and miR NC group was set as control group. CCK-8 method was used to detect the change in cell proliferation. Flow cytometry was used to detect the changes in cell cycles. Wound healing experiments and Transwell migration experiments were used to detect the changes in cell migration ability. The target gene of miR-181a-5p was predicted by Targetscan website and validated by Dual-luciferase reporter gene system and Western blot. RESULTS: Compared with osteoblast hFOB1.19, miR-181a-5p was low expressed in osteosarcoma cells HOS, U2OS, and MG63(P<0.05), while HOXB4 was high expressed in osteosarcoma cells HOS, U2OS, and MG63(P<0.05). Compared with the miR NC group, over expression of miR-181a-5p inhibited the proliferation and migration of osteosarcoma HOS cells, and the number of cells in S phase decreased(P<0.05). However, knockdown miR-181a-5p promoted the proliferation and migration of osteosarcoma HOS cells, the cells in S phase increased(P<0.05). Bioinformatics prediction and Dual-luciferase reporter gene system validate HOXB4 as a downstream target gene of miR-181a-5p(P<0.05). Western blot showed that miR-181a-5p over expression or knockdown significantly down-regulated or up-regulated HOXB4 expressions in the HOS cells respectively(P<0.05). CONCLUSION: miR-181a-5p is down expressed in osteosarcoma cells, and over-expression miR-181a-5p inhibits the proliferation, cell cycle and migration ability of osteosarcoma cells by targeting HOXB4.


Assuntos
Neoplasias Ósseas , Proteínas de Homeodomínio , MicroRNAs , Osteossarcoma , Fatores de Transcrição , Humanos , Apoptose , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas de Homeodomínio/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Osteossarcoma/genética , Fatores de Transcrição/genética
13.
Materials (Basel) ; 15(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35407921

RESUMO

The influence of tempering temperature on the microstructure of 0.5Cr0.4W steels was investigated by scanning electron microscope, and the roles of grain boundary character, dislocation, and Taylor factor in sulfide stress cracking (SSC) resistance were interpreted using the election backscattered diffraction technique. The 0.5Cr0.4W steels tempered at 690 °C, 700 °C, and 715 °C all showed tempered martensites. The specimen tempered at 715 °C exhibited a higher critical stress intensity factor (KISSC) of 34.58 MPa·m0.5, but the yield strength of 800 MPa did not meet the criterion of 125 ksi (862 MPa) grade. When the specimen was tempered at 690 °C, the yield strength reached 960 MPa and the KISSC was only 21.36 MPa·m0.5, displaying poorer SSC resistance. The 0.5Cr0.4W steel tempered at 700 °C showed a good combination of yield strength (887 MPa) and SSC resistance (KISSC: 31.16 MPa·m0.5). When increasing the tempering temperature, the local average misorientation and Taylor factor of the 0.5Cr0.4W steels were decreased. The reduced dislocation density, and greater number of grains amenable to slippage, produced less hydrogen transport and a lower crack sensitivity. The SSC resistance was, thus, increased, owing to the minor damage to hydrogen aggregation. Therefore, 700 °C is a suitable tempering temperature for 0.5Cr0.4W casing steel.

14.
Ann Transl Med ; 9(16): 1289, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532426

RESUMO

BACKGROUND: To compare the long-term therapeutic effects of stereotactic aspiration (SA), endoscopic evacuation (EE), and open craniotomy (OC) in the surgical treatment of spontaneous basal ganglia hemorrhage and explore the appropriate clinical indications for each technique. METHODS: Multiple-treatment inverse probability of treatment weighting (IPTW)-adjusted logistic regression analysis was performed to evaluate the therapeutic effects of these techniques. The primary and secondary outcomes were 6-month modified Rankin Scale (mRS) and mortality rates, respectively. RESULTS: A total of 703 patients were ultimately enrolled. For the entire cohort, the 6-month mortality rate was significantly higher (OR 2.396, 95% CI: 1.865-3.080), and the 6-month functional outcome was significantly worse (OR 1.359, 95% CI: 1.091-1.692) for SA than that of EE. The 6-month mortality rate for OC was significantly higher (OR 1.395, 95% CI: 1.059-1.837) than that of EE. Further subgroup analysis was stratified by initial hematoma volume and Glasgow Coma Scale (GCS) score. The mortality rate for SA was significantly higher for patients with hematoma volume of 20-40 mL (OR 6.226, 95% CI: 3.848-10.075), 40-80 mL (OR 2.121, 95% CI: 1.492-3.016), and ≥80 mL (OR 5.544, 95% CI: 3.315-9.269) than in the same subgroups of EE. The functional outcomes for SA were significantly worse than that of EE for hematoma volume subgroups of 40-80 mL (OR 1.424, 95% CI: 1.039-1.951) and ≥80 mL (OR 4.224, 95% CI: 1.655-10.776). The mortality rate for SA was significantly higher than that of EE for the GCS score subgroups of 6-8 (OR 2.082, 95% CI: 1.410-3.076) and 3-5 (OR 2.985, 95% CI: 1.904-4.678). The mortality rate for OC was significantly higher for the GCS score of 3-5 subgroup (OR 1.718, 95% CI: 1.115-2.648), and a tendency for a higher mortality rate of 6-8 subgroup (OR 1.442, 95% CI: 0.965-2.156) than that of EE. CONCLUSIONS: EE can decrease the 6-month mortality rate and improve the 6-month functional outcomes of spontaneous basal ganglia hemorrhage in patients with a hematoma volume ≥40 mL. EE can decrease the 6-month mortality rate of spontaneous basal ganglia hemorrhage in patients with a GCS score of 3-8.

15.
Mar Drugs ; 19(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069724

RESUMO

Three new p-terphenyl derivatives, named 4″-O-methyl-prenylterphenyllin B (1) and phenylcandilide A and B (17 and 18), and three new indole-diterpene alkaloids, asperindoles E-G (22-24), were isolated together with eighteen known analogues from the fungi Aspergillus candidus associated with the South China Sea gorgonian Junceela fragillis. The structures and absolute configurations of the new compounds were elucidated on the basis of spectroscopic analysis, and DFT/NMR and TDDFT/ECD calculations. In a primary cultured cortical neuronal network, the compounds 6, 9, 14, 17, 18 and 24 modulated spontaneous Ca2+ oscillations and 4-aminopyridine hyperexcited neuronal activity. A preliminary structure-activity relationship was discussed.


Assuntos
Antozoários/parasitologia , Aspergillus/química , Diterpenos/farmacologia , Alcaloides Indólicos/farmacologia , Neurônios/efeitos dos fármacos , Compostos de Terfenil/farmacologia , Animais , Antozoários/microbiologia , Organismos Aquáticos/química , Sinalização do Cálcio , Diterpenos/química , Diterpenos/isolamento & purificação , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Oceanos e Mares , Cultura Primária de Células , Relação Estrutura-Atividade , Compostos de Terfenil/química , Compostos de Terfenil/isolamento & purificação
16.
Glob Chang Biol ; 27(11): 2561-2579, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33666308

RESUMO

A quantitative understanding of physiological thermal responses is vital for forecasting species distributional shifts in response to climate change. Many studies have focused on metabolic rate as a global metric for analyzing the sublethal effects of changing environments on physiology. Thermal performance curves (TPCs) have been suggested as a viable analytical framework, but standard TPCs may not fully capture physiological responses, due in part to failure to consider the process of metabolic depression. We derived a model based on the nonlinear regression of biological temperature-dependent rate processes and built a heart rate data set for 26 species of intertidal molluscs distributed from 33°S to ~40°N. We then calculated physiological thermal performance limits with continuous heating using T 1 / 2 H , the temperature at which heart rate is decreased to 50% of the maximal rate, as a more realistic measure of upper thermal limits. Results indicate that heat-induced metabolic depression of cardiac performance is a common adaptive response that allows tolerance of harsh environments. Furthermore, our model accounted for the high inter-individual variability in the shape of cardiac TPCs. We then used these TPCs to calculate physiological thermal safety margins (pTSM), the difference between the maximal operative temperature (95th percentile of field temperatures) and T 1 / 2 H of each individual. Using pTSMs, we developed a physiological species distribution model (pSDM) to forecast future geographic distributions. pSDM results indicate that climate-induced species range shifts are potentially less severe than predicted by a simple correlative SDM. Species with metabolic depression below the optimum temperature will be more thermal resistant at their warm trailing edges. High intraspecific variability further suggests that models based on species-level vulnerability to environmental change may be problematic. This multi-scale, mechanistic understanding that incorporates metabolic depression and inter-individual variability in thermal response enables better predictions about the relationship between thermal stress and species distributions.


Assuntos
Termotolerância , Adaptação Fisiológica , Mudança Climática , Temperatura Alta , Temperatura
17.
Exp Ther Med ; 21(3): 233, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33603841

RESUMO

The NLR family pyrin domain-containing 3 (NLRP3) inflammasome, which is composed of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC) and pro-caspase-1 protein complexes, is activated by the reactive oxygen species (ROS) that are associated with ischemia-reperfusion (I/R) and are involved in brain damage. Pomelo peel oil (PPO) exhibits antioxidant activity. However, it is unclear whether PPO is able to attenuate NLRP3 inflammasome-induced inflammation and pyroptosis. Healthy male Sprague-Dawley rats were subjected to 7 min of cardiac arrest via trans-esophageal electrical stimulation, followed by cardiopulmonary resuscitation (CPR). The rats were then treated with PPO prior to reperfusion for 24 h. Hematoxylin and eosin staining was used to evaluate brain tissue and cell damage. In the brain tissues, reactive oxygen species (ROS) were assayed, immunofluorescence was used to analyze the expression of NLRP3 and western blotting was performed to determine the expression levels of neuroenolase (NSE), NF-κB, interleukin-1ß (IL-1ß), gasdermin D (GSDMD) and the NLRP3 inflammasome. Treatment of the rats with PPO significantly decreased the pathological damage of the brain tissue and reduced the expression of NSE, production of ROS and secretion of NF-κB, NLRP3, IL-1ß and GSDMD. In conclusion, these results demonstrate the ability of PPO to protect the brain against I/R injury in rats after CPR by a mechanism involving inhibition of the inflammation and pyroptosis mediated by NLRP3 inflammasome activation.

18.
Curr Pharm Biotechnol ; 22(14): 1878-1890, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33390110

RESUMO

BACKGROUND: Restoration of blood flow during ischemic stroke leads to Cerebral Ischemia- Reperfusion Injury (CIRI) by activating neuroinflammatory cascades. Pomelo Peel Volatile Oil (PPVO) extracted from Citrus maxima (Burm.) from the genus Rutaceae, comprises some antiinflammatory ingredients, such as limonene and ß-myrcene. OBJECTIVE: The present study aimed to investigate the potential effect of PPVO on alleviating CIRI related to the Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) pathway. METHODS: Transient middle cerebral artery occlusion/reperfusion (tMCAO/R) was performed on 65 rats, which were then distributed into five groups (n = 13/group) depending on the intervention they received: Normal Saline (NS) group, normal Glycerin (GL) group, low-dose PPVO (LP, 10mg/kg) group, high-dose PPVO (HP, 30 mg/kg) group, and Sham-operated (SH) group. Neurological Deficit Scores (NDSs) and histological changes were evaluated. Infarct volumes were measured by 2,3,5- Triphenyltetrazolium Chloride (TTC) staining. The expression of TLR4 and neutrophil infiltration were detected by Immunofluorescence (IF) staining. Moreover, the downstream molecules of the TLR4/NF-κB signaling pathway, such as IL-6, IL-1ß, TNF-α, p-IκB/IκB, and p-NF-κB p65/NF-κB p65 were analyzed by Western Blot (WB). RESULTS AND DISCUSSION: The results showed that PPVO (30 mg/kg) significantly decreased infarct volumes, improved neurological deficits and pathologic changes, inhibited TLR4/NF-κB signaling pathway suppressed neutrophil infiltration, and suppressed pro-inflammatory cytokine release. CONCLUSION: It can be concluded that PPVO may alleviate neuroinflammation and protect against CIRI via inhibiting the TLR4/NF-κB signaling pathway.


Assuntos
Isquemia Encefálica , Óleos Voláteis , Traumatismo por Reperfusão , Animais , Isquemia Encefálica/tratamento farmacológico , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Reperfusão , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais , Receptor 4 Toll-Like
19.
Int Immunopharmacol ; 93: 107377, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33517223

RESUMO

BACKGROUND: Cerebral ischemia-reperfusion injury (CIRI) is the leading cause of poor neurological prognosis after cardiopulmonary resuscitation (CPR). We previously reported that the extracellular signal-regulated kinase (ERK) activation mediates CIRI. Here, we explored the potential ERK/calpain-2 pathway role in CIRI using a rat model of cardiac arrest (CA). METHODS: Adult male Sprague-Dawley rats suffered from CA/CPR-induced CIRI, received saline, DMSO, PD98059 (ERK1/2 inhibitor, 0.3 mg/kg), or MDL28170 (calpain inhibitor, 3.0 mg/kg) after spontaneous circulation recovery. The survival rate and the neurological deficit score (NDS) were utilized to assess the brain function. Hematoxylin stain, Nissl staining, and transmission electron microscopy were used to evaluate the neuron injury. The expression levels of p-ERK, ERK, calpain-2, neuroinflammation-related markers (GFAP, Iba1, IL-1ß, TNF-α), and necroptosis proteins (TNFR1, RIPK1, RIPK3, p-MLKL, and MLKL) in the brain tissues were determined by western blotting and immunohistochemistry. Fluorescent multiplex immunohistochemistry was used to analyze the p-ERK, calpain-2, and RIPK3 co-expression in neurons, and RIPK3 expression levels in microglia or astrocytes. RESULTS: At 24 h after CA/CPR, the rats in the saline-treated and DMSO groups presented with injury tissue morphology, low NDS, ERK/calpain-2 pathway activation, and inflammatory cytokine and necroptosis protein over-expression in the brain tissue. After PD98059 and MDL28170 treatment, the brain function was improved, while inflammatory response and necroptosis were suppressed by ERK/calpain-2 pathway inhibition. CONCLUSION: Inflammation activation and necroptosis involved in CA/CPR-induced CIRI were regulated by the ERK/calpain-2 signaling pathway. Inhibition of that pathway can reduce neuroinflammation and necroptosis after CIRI in the CA model rats.


Assuntos
Isquemia Encefálica/imunologia , Calpaína/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Parada Cardíaca/imunologia , Traumatismo por Reperfusão/imunologia , Animais , Calpaína/imunologia , Dipeptídeos/farmacologia , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Flavonoides/farmacologia , Inflamação/imunologia , Masculino , Necroptose , Ratos Sprague-Dawley , Transdução de Sinais
20.
Oncol Lett ; 21(2): 80, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33363617

RESUMO

Ovarian cancer ranks 7th among the most common cancer types affecting women worldwide. A number of studies have confirmed that multiple long non-coding RNAs participate in the occurrence and progression of ovarian cancer. Small nucleolar RNA host gene 9 (SNHG9) serves a role in the progression of glioblastoma and pancreatic cancer. However, the specific biological function of SNHG9 in ovarian cancer has not yet been fully investigated. The present study aimed to determine the biological role and potential molecular mechanism underlying the influence of SNHG9 in ovarian cancer. SNHG9 expression in ovarian cancer cell lines and tissues were measured via reverse transcription-quantitative PCR analysis, and cell proliferation was detected via Cell Counting Kit-8 and colony formation assays. Flow cytometry was performed to assess cell cycle progression, and Transwell and wound healing assays were performed to assess cell invasion and migration abilities. Bioinformatics software was utilized to determine the target genes of SNHG9, which were subsequently verified via dual-luciferase reporter and RNA immunoprecipitation assays. The results demonstrated that SNHG9 expression was remarkably lower in ovarian cancer cell lines and tissues compared with the negative controls. Cell function assays demonstrated that decreased SNHG9 expression notably induced the migration, colony formation, proliferation and invasiveness of ovarian cancer cells. Furthermore, the inhibitory effect of SNHG9 on the migration, colony formation, proliferation and invasion of ovarian cancer cells was partially reversed by miR-214-5p upregulation. Thus, taken together, the current results suggest that SNHG9 may serve as a tumor suppressor gene in ovarian cancer by regulating the miR-214-5p/cryptochrome circadian regulator 2 axis.

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