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Traditional current-driven spintronics is limited by localized heating issues and large energy consumption, restricting their data storage density and operation speed. Meanwhile, voltage-driven spintronics with much lower energy dissipation also suffers from charge-induced interfacial corrosion. Thereby finding a novel way of tuning ferromagnetism is crucial for spintronics with energy-saving and good reliability. Here, a visible light tuning of interfacial exchange interaction via photoelectron doping into synthetic antiferromagnetic heterostructure of CoFeB/Cu/CoFeB/PN Si substrate is demonstrated. Then, a complete, reversible magnetism switching between antiferromagnetic (AFM) and ferromagnetic (FM) states with visible light on and off is realized. Moreover, a visible light control of 180° deterministic magnetization switching with a tiny magnetic bias field is achieved. The magnetic optical Kerr effect results further reveal the magnetic domain switching pathway between AFM and FM domains. The first-principle calculations conclude that the photoelectrons fill in the unoccupied band and raise the Fermi energy, which increases the exchange interaction. Lastly, a prototype device with visible light control of two states switching with a 0.35% giant magnetoresistance ratio change (maximal 0.4%), paving the way toward fast, compact, and energy-efficient solar-driven memories is fabricated.
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Finding an energy-efficient way of switching magnetization is crucial in spintronic devices, such as memories. Usually, spins are manipulated by spin-polarized currents or voltages in various ferromagnetic heterostructures; however, their energy consumption is relatively large. Here, a sunlight control of perpendicular magnetic anisotropy (PMA) in Pt (0.8 nm)/Co (0.65 nm)/Pt (2.5 nm)/PN Si heterojunction in an energy-efficient manner is proposed. The coercive field (HC ) is altered from 261 to 95 Oe (64% variation) under sunlight illumination, enabling a nearly 180° deterministic magnetization switching reversibly with a 140 Oe magnetic bias assistant. The element-resolved X-ray circular dichroism measurement reveals different L3 and L2 edge signals of the Co layer with or without sunlight, suggesting a photoelectron-induced redistribution of the orbital and spin moment in Co magnetization. The first-principle calculations also reveal that the photo-induced electrons shift the Fermi level of electrons and enhance the in-plane Rashba field around the Co/Pt interfaces, leading to a weakened PMA and corresponding HC decreasing and magnetization switching accordingly. The sunlight control of PMA may provide an alternative way for magnetic recording, which is energy efficient and would reduce the Joule heat from the high switching current.
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A sensitive and specific high-performance liquid chromatography-tandem mass spectrometry method has been developed to determine the pharmacokinetic interactions of the antiplatelet agents aspirin and clopidogrel combined with dl-3-n-butylphthalide. For the determination of aspirin metabolite salicylic acid, clopidogrel inactive metabolite SR26334 and NBP prototype drug in rat plasma, plasma samples were prepared by precipitation of proteins using methanol containing 0.1% formic acid, followed by centrifugation. Chromatography was performed on a C18 column, eluting with a gradient of acetonitrile (with 0.1% formic acid)-water (with 0.1% formic acid). The detection adopted electrospray ion source and positive ion multiple reaction monitoring modes. The linear detection response range of salicylic acid is 80-80,000 ng/ml, and the linear detection response range of SR26334 and dl-3-n-butylphthalide is 10-10,000 ng/ml. Our study revealed that dl-3-n-butylphthalide affected the pharmacokinetics of aspirin and clopidogrel when administered to rats.
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Aspirina , Inibidores da Agregação Plaquetária , Ratos , Animais , Inibidores da Agregação Plaquetária/farmacocinética , Clopidogrel , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Ácido SalicílicoRESUMO
We report the synthesis and biological evaluation of 131 I-labeled antihuman tumor-derived immunoglobulin G (IgG) light chain monoclonal antibody (4E9) ([131 I]I-4E9) as a promising probe for tumor imaging. [131 I]I-4E9 was synthesized in radiochemical yield of 89.9 ± 4.7% with radiochemical purity of more than 99%. [131 I]I-4E9 showed high stability in normal saline and human serum. In cell uptake studies, [131 I]I-4E9 exhibited favorable binding affinity and high specificity in HeLa MR cells. In biodistribution studies, [131 I]I-4E9 showed high tumor uptake, high tumor/non-tumor ratios, and specific binding in BALB/c nu/nu mice bearing human HeLa MR xenografts. Single-photon emission computerized tomography (SPECT) imaging of [131 I]I-4E9 in the HeLa MR xenograft model demonstrated clear visualization of tumor after 48 h and confirmed specific binding in tumor. These findings suggest that [131 I]I-4E9 possesses favorable biological characteristics and warrants further investigation as a prospective probe for imaging and treatment of cancers.
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Anticorpos Monoclonais , Neoplasias , Animais , Camundongos , Humanos , Camundongos Nus , Radioisótopos do Iodo , Cadeias Leves de Imunoglobulina/metabolismo , Imunoglobulina G , Distribuição Tecidual , Estudos Prospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Linhagem Celular TumoralRESUMO
Chemotherapy is an important method for the treatment of lung cancer, but multidrug resistance (MDR) greatly reduces the efficacy. The superfamily of ATP-binding cassette (ABC) transport proteins is related to MDR. As a subfamily of ABC proteins, ABCG2/BCRP (breast cancer resistance protein, BCRP) is considered a major player in the development of cancer MDR. For the stratification of chemotherapeutic choices, we constructed Cy5.5- or 89Zr-labeled ABCG2-targeted monoclonal antibody (mAb) ABCG2-PKU1 for noninvasive evaluation of ABCG2 expression in lung cancer xenograft models. ABCG2 expression was screened in H460/MX (mitoxantrone resistant), H460, and H1299 human lung cancer cell lines using Western blotting. ELISA, flow cytometry, and cell immunofluorescent staining were used to evaluate the binding ability of ABCG2-PKU1 to ABCG2 antigen. Lung cancer murine xenograft models were built for in vivo experiments. ABCG2-PKU1 was labeled with Cy5.5 (Cy5.5-ABCG2) for fluorescent imaging and radiolabeled with 89Zr (89Zr-DFO-ABCG2) for immunoPET imaging following the conjugation with p-SCN-deferoxamine (DFO). In vivo imaging was performed in lung cancer models at 2, 24, 48, 72, 96, 120, 144, and 168 h postinjection. Ex vivo biodistribution was conducted after the terminal time point of imaging. Finally, tissue immunohistochemical staining was used to evaluate the tumor expression of ABCG2. Western blotting showed that the H460/MX cells had a high ABCG2 expression level whereas H460 and H1299 had moderate and low levels. ELISA, flow cytometry, and cell immunofluorescent staining results validated the good binding affinity between ABCG2-PKU1 and ABCG2. The H460/MX and H460 cells were used to build positive lung cancer models, and H1299 cells were used to build negative models. The fluorescent imaging showed that the tumor average radiant efficiency of Cy5.5-ABCG2 reached the maximum at 72 and 120 h in H460/MX and H460 respectively (n = 3, P < 0.01). The tumor uptake of Cy5.5-ABCG2 in H1299 (n = 3) was significantly lower than H460/MX and H460 (P < 0.01). ImmunoPET imaging showed that the tumor uptake of 89Zr-DFO-ABCG2 in H460/MX was significantly higher than H460, with a maximum of 4.15 ± 0.41 %ID/g and 2.81 ± 0.24 %ID/g at 168 and 144 h, respectively (n = 5, P < 0.01). The H1299 tumors showed significantly lower uptake than H460/MX and H460 (n = 5, P < 0.01). The radioactive uptake of 89Zr-DFO-ABCG2 among three groups in the heart, liver, and kidney gradually decreased over time. Ex vivo biodistribution verified the differential tumor uptake among the three groups (P < 0.01). Immunohistochemical staining revealed that the H460/MX tumor had the highest expression of ABCG2, whereas H460 and H1299 had the moderate and lowest expression, respectively. Therefore, in this study, fluorescent and immunoPET imaging of lung cancer MDR models using Cy5.5-ABCG2 and 89Zr-DFO-ABCG2 noninvasively evaluated the differential expression of ABCG2, which are expected to be used for the diagnosis and the selection for clinical treatment options for lung cancer MDR patients in future applications.
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Neoplasias Pulmonares , Mitoxantrona , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Carbocianinas , Linhagem Celular Tumoral , Desferroxamina , Modelos Animais de Doenças , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Xenoenxertos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Proteínas de Neoplasias/metabolismo , Distribuição TecidualRESUMO
Low-cost heteroatom-doped carbon nanomaterials have been widely studied for efficient oxygen reduction reaction and energy storage and conversion in metal-air batteries. A Masson pine twigs-like 3-dimensional network construction of carbon nanofibers (CNFs) with abundant straight long Co, N, and S-doped carbon nanotubes (CNTs) is developed by thermal treatment of Co-based polymer coated onto polyacrylonitrile nanofiber network together with thiourea at 900 °C, denoted as CNFT-Co9 S8 -900. It is interesting to note that the introduction of a high concentration of sulfur does not lead to the complete toxicity of catalysts, but promotes the axial growth to selectively form straight CNTs instead of curly bamboo-like CNTs. The highly graphitized in-situ grown Co, N, S-doped CNTs and the 3-dimensional N-doped CNF network provide both active catalytic sites and highly conductive paths, which are beneficial for oxygen reduction reaction (ORR). Thus, the optimal CNFT-Co9 S8 -900 performs the excellent ORR catalytic activity with a half-wave potential of 0.84â V and a diffusion-limited current density of 5.49â mA cm-2 . Furthermore, the CNFT-Co9 S8 -900-based Zn-air devices also possess a high power density of 136.9â mW cm-2 better than commercial Pt/C.
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Arg-Arg-Leu (RRL) is a potent tumor-homing tripeptide. However, the binding target is unclear. In this study, we intended to identify the binding target of RRL and evaluate the tumor targeting of 99mTc-MAG3-RRL in vivo. Biotin-RRL, 5-TAMRA-RRL, and 99mTc-MAG3-RRL were designed to trace the binding target and tumor lesion. Immunoprecipitation-mass spectrometry was conducted to identify the candidate proteins and determination of the subcellular localization was also performed. A pull-down assay was performed to demonstrate the immunoprecipitate. Fluorescence colocalization and cell uptake assays were performed to elucidate the correlation between the selected binding protein and RRL, and the internalization mechanism of RRL. Biodistribution and in vivo imaging were performed to evaluate the tumor accumulation and targeting of 99mTc-MAG3-RRL. The target for RRL was screened to be heat shock protein 70 (HSP70). The prominent uptake distribution of RRL was concentrated in the membrane and cytoplasm. A pull-down assay demonstrated the existence of HSP70 in the biotin-RRL captured complex. Regarding fluorescence colocalization and cell uptake assays, RRL may interact with HSP70 at the nucleotide-binding domain (NBD). Clathrin-dependent endocytosis and macropinocytosis could be a vital internalization mechanism of RRL. In vivo imaging and biodistribution both demonstrated that 99mTc-MAG3-RRL can trace tumors with satisfactory accumulation in hepatoma xenograft mice. The radioactive signals accumulated in tumor lesions can be blocked by VER-155008, which can bind to the NBD of HSP70. Our findings revealed that RRL may interact with HSP70 and that 99mTc-MAG3-RRL could be a prospective probe for visualizing overexpressed HSP70 tumor sections.
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Proteínas de Choque Térmico HSP70/metabolismo , Neoplasias/diagnóstico por imagem , Oligopeptídeos/metabolismo , Animais , Sítios de Ligação , Feminino , Citometria de Fluxo , Células HeLa/metabolismo , Células Hep G2/metabolismo , Humanos , Imunoprecipitação , Células MCF-7/metabolismo , Espectrometria de Massas , Camundongos , Camundongos Nus , Imagem Óptica , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
Oxidative stress is one of the hallmarks of ischemic stroke. Catalase-based (CAT) biomimetic complexes are emerging as promising therapeutic candidates that are expected to act as neuroprotectants for ischemic stroke by decreasing the damaging effects from H2O2. Unfortunately, these molecules result in the unwanted production of the harmful hydroxyl radical, HOâ¢. Here, we report a series of salen-based tri-manganese (Mn(III)) metallocryptands (1-3) that function as catalase biomimetics. These cage-like molecules contain a unique "active site" with three Mn centers in close proximity, an arrangement designed to facilitate metal cooperativity for the effective dismutation of H2O2 with minimal HO⢠production. In fact, significantly greater oxygen production is seen for 1-3 as compared to the monomeric Mn(Salen) complex, 1c. The most promising system, 1, was studied in further detail and found to confer a greater therapeutic benefit both in vitro and in vivo than the monomeric control system, 1c, as evident from inter alia studies involving a rat model of ischemic stroke damage and supporting histological analyses. We thus believe that metallocryptand 1 and its analogues represent a new and seemingly promising strategy for treating oxidative stress related disorders.
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Antioxidantes/farmacologia , Isquemia Encefálica/tratamento farmacológico , Complexos de Coordenação/farmacologia , AVC Isquêmico/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Antioxidantes/síntese química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Catalase/metabolismo , Células Cultivadas , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Modelos Animais de Doenças , Etilenodiaminas/química , Etilenodiaminas/farmacologia , Humanos , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Masculino , Manganês/química , Manganês/farmacologia , Conformação Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Imagem Óptica , Oxigênio/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
DL-3-n-butylphthalide (NBP) is isolated from the seeds of Apium graveolens L., and has been recently used as a neuroprotective agent for acute ischemic stroke. The present study aimed to determine the efficacy and safety of the combined use of dual antiplatelet therapy (DAPT) and NBP for treating of acute ischemic stroke in rats and to explore the synergistic mechanism of this treatment strategy in rat middle cerebral artery occlusion models. The efficacy of DAPT combined with NBP was evaluated by determining neurological deficits, infarction status, and histological changes. Changes in body weight, blood glucose level, blood count, and serum biochemical parameters were detected to evaluate the safety. To explore the synergistic pharmacological mechanism, the mRNA expression and protein levels of key proteins in the pyroptosis-inflammatory pathway, and the pyroptosis ratio of microglias were examined. Compared with the administration of NBP or DAPT alone, combination of them significantly improved neurological deficits, reduced infarct area, and repaired tissue injury and inflammation after cerebral ischemia. No hepatorenal toxicity was observed. The mRNA expression and protein levels of key proteins in the pyroptosis-inflammation pathway, and the pyroptosis ratio of microglias were significantly downregulated in the combined administration group than in the monotherapy group. We demonstrated that the combined use of NBP and DAPT exhibits better efficacy and high safety and plays a synergistic role by inhibiting the pyroptosis-inflammation pathway in the brain tissues, particularly in microglial cells.
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Benzofuranos , Isquemia Encefálica , AVC Isquêmico , Fármacos Neuroprotetores , Acidente Vascular Cerebral , Ratos , Animais , AVC Isquêmico/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Inflamação/tratamento farmacológico , RNA Mensageiro , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
BACKGROUND: Tegoprazan is a potassium-competitive acid blocker that inhibits gastric acid and which may be used for eradicating Helicobacter pylori. This study focuses on the pharmacokinetic interaction and safety between tegoprazan and the combination of clarithromycin, amoxicillin and bismuth in healthy Chinese subjects. METHODS: An open-label, three-period, single-center, multiple-dosage, single-sequence, phase I trial was conducted in 22 healthy subjects. In period 1, the subjects took tegoprazan 50 mg twice daily for 7 days, and in period 2 they were administered clarithromycin 500 mg, amoxicillin 1000 mg and bismuth potassium citrate 600 mg twice daily for 7 days (days 14-20). Tegoprazan, clarithromycin, amoxicillin and bismuth potassium citrate were then administered in combination for 7 days (days 21-27) in period 3. Blood samples were collected up to 12 h after the last dose of each period. Safety assessments were performed in each period. RESULTS: The geometric mean ratios (GMRs) [90% confidence interval (CI)] of maximum plasma concentration at steady state (Cmax,ss) and area under the plasma concentration-time curve over the dosing interval (AUCτ) at steady state were 195.93% (175.52-218.71%) and 287.54% (263.28-314.04%) for tegoprazan and 423.23% (382.57-468.22%) and 385.61% (354.62-419.30%) for tegoprazan metabolite M1, respectively. The GMRs (90% CI) of Cmax,ss and AUCτ were 83.69% (77.44-90.45%) and 110.30% (102.74-118.41%) for clarithromycin, 126.25% (114.73-138.93%) and 146.94% (135.33-159.55%) for 14-hydroxyclarithromycin, 75.89% (69.73-82.60%) and 94.34% (87.94-101.20%) for amoxicillin, and 158.43% (125.43-200.11%) and 183.63% (156.42-215.58%) for bismuth, respectively. All reported adverse events were mild. The frequency of adverse events during the coadministration stage was not higher than that during the single- or triple-drug administration stages. CONCLUSION: The plasma exposure of tegoprazan, M1, 14-hydroxyclarithromycin and bismuth was increased after the coadministration of tegoprazan, clarithromycin, amoxicillin and bismuth. The coadministration exhibited favorable safety and tolerability. CLINICAL TRIALS REGISTRATION: CTR20230643.
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Amoxicilina , Derivados de Benzeno , Bismuto , Claritromicina , Interações Medicamentosas , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Amoxicilina/efeitos adversos , Amoxicilina/farmacocinética , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Área Sob a Curva , Bismuto/efeitos adversos , Bismuto/farmacocinética , China , Claritromicina/efeitos adversos , Claritromicina/farmacocinética , População do Leste Asiático , Voluntários Saudáveis , Inibidores da Bomba de Prótons/efeitos adversos , Inibidores da Bomba de Prótons/farmacocinética , Imidazóis/efeitos adversos , Imidazóis/farmacocinética , Derivados de Benzeno/efeitos adversos , Derivados de Benzeno/farmacocinéticaRESUMO
HYPOTHESIS: In a porous medium saturated with oil (containing oleic surfactant) and saline water, salinity reduction alters the thermodynamic equilibrium and induces spatial redistribution of surfactants, changing the local fluid configuration. During fluid-fluid displacement, this local change reshapes global fluid flows, and thus results in improved oil displacement. EXPERIMENTS: We performed microfluidic experiments in a centimeter-long pore-network model with a fracture and a dead-end model to observe both the macroscale flows and microscopic fluid configuration evolution. Water with different salinities and model oils with different surfactant concentrations are used. FINDINGS: When oil contacts low salinity water, we observe (1) the solid surface becomes more water-wet, and (2) water-in-oil emulsion spontaneously emerges near the oil-water interface. At the macroscale, the fluid distribution remains unchanged in short term but dramatically changes after tens of hours, which appears as improved oil recovery. Two modes are identified during fluid redistribution: gradual imbibition and sudden collapse. The displacement efficiency is a non-monotonic function of surfactant concentration. This is attributed to the interplay between two opposing effects by adding surfactant: (1) enhancing initial hydrophobicity which negatively affects the displacement, and (2) allowing stronger oil swelling which is beneficial for displacement.
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Águas Salinas , Salinidade , Tensoativos , Óleos , PorosidadeRESUMO
The flexible electronics have application prospects in many fields, including as wearable devices and in structural detection. Spintronics possess the merits of a fast response and high integration density, opening up possibilities for various applications. However, the integration of miniaturization on flexible substrates is impeded inevitably due to the high Joule heat from high current density (1012 A/m2). In this study, a prototype flexible spintronic with device antiferromagnetic/ferromagnetic heterojunctions is proposed. The interlayer coupling strength can be obviously altered by sunlight soaking via direct photo-induced electron doping. With the assistance of a small magnetic field (±125 Oe), the almost 180° flip of magnetization is realized. Furthermore, the magnetoresistance changes (15~29%) of flexible spintronics on fingers receiving light illumination are achieved successfully, exhibiting the wearable application potential. Our findings develop flexible spintronic sensors, expanding the vision for the novel generation of photovoltaic/spintronic devices.
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Oxidative stress from reactive oxygen species (ROS) is a reperfusion injury factor that can lead to cell damage and death. Here, ultrasmall iron-gallic acid coordination polymer nanodots (Fe-GA CPNs) were developed as antioxidative neuroprotectors for ischemia stroke therapy guided by PET/MR imaging. As proven by the electron spin resonance spectrum, the ultrasmall Fe-GA CPNs with ultrasmall size, scavenged ROS efficiently. In vitro experiments revealed that Fe-GA CPNs could protect cell viability after being treated with hydrogen peroxide (H2O2) and displayed the effective elimination of ROS by Fe-GA CPNs, which subsequently restores oxidation balance. When analyzing the middle cerebral artery occlusion model, the neurologic damage displayed by PET/MR imaging revealed a distinct recovery after treatment with Fe-GA CPNs, which was proved by 2,3,5-triphenyl tetrazolium chloride staining. Furthermore, immunohistochemistry staining indicated that Fe-GA CPNs inhibited apoptosis through protein kinase B (Akt) restoration, whereas western blot and immunofluorescence indicated the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) pathway following Fe-GA CPNs application. Therefore, Fe-GA CPNs exhibit an impressive antioxidative and neuroprotective role via redox homeostasis recovery by Akt and Nrf2/HO-1 pathway activation, revealing its potential for clinical ischemia stroke treatment.
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Spin waves are considered to be an alternative carrier with great promise for information sensing. The feasible excitation and low-power manipulation of spin waves still remain a challenge. In this regard, natural light enablings spin-wave tunability in Co60 Al40 -alloyed film is investigated. A reversible shift of the critical angle (from 81° in the dark to 83° under illumination) of the body spin-wave is achieved successfully Meanwhile, an eye-catching shift (817 Oe) of the ferromagnetic resonance (FMR) field is obtained optically, leading to changes in magnetic anisotropy. Based on the modified Puszkarski's surface inhomogeneity model, the control of spin-wave resonance (SWR) by sunlight can be understood by an effective photoelectron-doping-induced change of the surface magnetic anisotropy. Furthermore, the body spin wave is modulated stably with natural light illumination, confirming a non-volatile, reversible switching behavior. This work has both practical and theoretical importance for developing future sunlight-tunable magnonics/spintronics devices.
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Atypical hemolytic uremic syndrome (aHUS) is a rare but severe type of thrombotic microangiopathy that is triggered by the abnormal activation of the alternative complement pathway. Previous studies have reported that three completely linked coding variants of CFHR1 form two haplotypes, namely, CFHR1*A (c.469C, c.475C, c.523G) and CFHR1*B (c.469T, c.475G, c.523C). CFHR1*B is associated with susceptibility to aHUS. To explore the genetic mechanism by which CFHR1 isoforms contribute to aHUS, we compared the structures of FHR1*A and FHR1*B by homology modeling and found differences in the angles between SCR3 and SCR4-SCR5, as FHR1*B had a larger angle than FHR1*A. Then, we expressed FHR1*A and FHR1*B recombinant proteins and compared their functions in complement system regulation and inflammation. We found that FHR1*B presented a significantly higher capacity for binding C3b and necrotic cells than FHR1*A. In a cofactor assay, the FHR-1*B showed stronger influence on FH mediated cofactor function than the FHR-1*A, resulted in fewer C3b cleavage products. In the C3 convertase assays, FHR1*B showed more powerful effect compared with FHR1*A regarding to de-regulate FH function of inhibition the assembling of C3bBb. Additionally, we also found that FHR1*B triggered monocytes to secrete higher levels of IL-1ß and IL-6 than FHR1*A. In the present study, we showed that variants of CFHR1 might differently affect complement activation and sterile inflammation. Our findings provide a possible mechanism underlying the predisposition to aHUS caused by CFHR1 isoform CFHR1*B.
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Síndrome Hemolítico-Urêmica Atípica/etiologia , Síndrome Hemolítico-Urêmica Atípica/metabolismo , Proteínas Sanguíneas/metabolismo , Ativação do Complemento/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Síndrome Hemolítico-Urêmica Atípica/diagnóstico , Ligação Competitiva/imunologia , Biomarcadores , Proteínas Sanguíneas/química , Complemento C3b/imunologia , Complemento C3b/metabolismo , Suscetibilidade a Doenças , Células Endoteliais/metabolismo , Humanos , Inflamação/complicações , Modelos Moleculares , Necrose/imunologia , Necrose/metabolismo , Ligação Proteica , Conformação Proteica , Isoformas de Proteínas , Relação Estrutura-AtividadeRESUMO
OBJECTIVE: Pep-1 (CGEMGWVRC) can potently bind to interleukin 13 receptor α 2 (IL-13Rα2), a tumor-restricted receptor found to be expressed in various malignancies. In this study, we intended to prepare a 99mTc-labeled probe and evaluate its in vivo tumor accumulation properties in a cervical cancer xenograft model. METHODS: The Pep-1 was designed and radiolabeled with 99mTc by conjugation with mercaptoacetyl-triglycine (MAG3). The labeling yield, radiochemical purity and stability were characterized in vitro. Cell uptake assays and fluorescence imaging were conducted for qualitative and quantitative evaluation of the specificity and affinity of Pep-1. Flow cytometry and tissue immunofluorescence were used to confirm the IL-13Rα2 expression in cervical cancer. Biodistribution and in vivo imaging were performed periodically to evaluate the imaging value of 99mTc-MAG3-Pep-1 in cervical cancer xenograft model. RESULTS: 99mTc-MAG3-Pep-1 was successfully prepared with a high labeling yield and radiochemical purity (> 95%). Specific cell uptake was demonstrated by scramble control and unlabeled MAG3-Pep-1 blockade. Flow cytometry and tissue immunofluorescence also confirmed the mild IL-13Rα2 expression of HeLa. In the gamma imaging study and biodistribution, the tumors were imaged clearly at 2-6 h after injection of 99mTc-MAG3-Pep-1 and the accumulation of 99mTc-MAG3-Pep-1 in tumor was significantly higher than that in the blocking and scramble controls, demonstrating ligand-receptor binding specificity. CONCLUSIONS: This work demonstrated that 99mTc-MAG3-Pep-1 can bind to cervical cancer with high affinity and specificity. MAG3-Pep-1 may be a prospective precursor for IL-13Rα2-expressing cancer therapy.
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Neoplasias do Colo do Útero , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Peptídeos , Estudos Prospectivos , Receptores de Interleucina-13 , Tecnécio/química , Distribuição Tecidual , Neoplasias do Colo do Útero/diagnóstico por imagemRESUMO
Exploring the flame propagation law in the process of gas explosion under different bifurcation angles is of great significance to the design of coal mine roadway and the prevention of gas explosion accidents. To study the variation of flame propagation law with bifurcation angle, an in-house experimental system based on a small scale three-way bifurcated pipe was developed to perform gas explosion experiments using mixtures of premixed methane-air with a methane concentration of 9.5%. Numerical simulations were conducted to study the propagation of the explosion flame. The results show that, (i) during the flame propagation process, the flame morphology evolves in the following manner: hemispherical, concave entrainment-deformation-flattening; (ii) in the case of gas explosion of three-way bifurcated pipes, there are significant differences in damage at different positions, and the damage at the pipe connection is the most serious. (iii) Although the parameters of the explosion flame in the bifurcated pipe exhibit similar trends across four different bifurcation angles, the values of the flame parameters obtained by the experiments and numerical simulations were not completely consistent. (iv) When the bifurcation angle is between the 45 and 75° bifurcation range, the area of the turbulent vortex formed by the air flow increases as the angle of the pipe widens. The research results analyze the propagation law of gas deflagration flame in the bifurcated pipeline, providing reference for the propagation mechanism of gas deflagration in underground bifurcated roadway and the formulation of prevention measures, which is conducive to preventing the propagation of gas explosion, reducing the intensity, and reducing the loss caused by gas explosion. However, large-scale tests are needed to determine the applicability of small-scale tests and calculations in this paper to full-scale mine conditions.
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Mesoporous carbon nanotubes (mCNTs) hold great promise interests, owing to their superior nano-platform properties for biomedicine. To fully utilize this potential, the toxicity and biodistribution of pristine and surface-modified mCNTs (-OH/-COOH) should preferentially be addressed. The results of cell viability suggested that pristine mCNTs induced cell death in a concentration-dependent manner. As evidence of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD), pristine mCNTs induced noticeable redox imbalance. 99mTc tracing data suggested that the cellular uptake of pristine mCNTs posed a concentrate-dependent and energy-dependent manner via macropinocytotic and clathrin-dependent pathways, and the main accumulated organs were lung, liver and spleen. With OH modification, the ROS generation, MDA deposition and SOD consumption were evidently reduced compared with the pristine mCNTs at 24/48 h high-dose exposure. With COOH modification, the modified mCNTs only showed a significant difference in SOD consumption at 24/48 h exposure, but there was no significant difference in the measurement of ROS and MDA. The internalization mechanism and organ distribution of modified mCNTs were basically invariant. Together, our study provides evidence that mCNTs and the modified mCNTs all could induce oxidative damage and thereby impair cells. 99mTc-mCNTs can effectively trace the distribution of nanotubes in vivo.
Assuntos
Nanotubos de Carbono , Animais , Camundongos , Humanos , Nanotubos de Carbono/toxicidade , Células Hep G2 , Distribuição Tecidual , Espécies Reativas de Oxigênio , PulmãoRESUMO
Inorganic/organic dielectric composites with outstanding energy storage properties at a low electric field possess the advantages of low operating voltage and small probability of failure. Composites filled with two-dimensional inorganic nanosheets have attracted much attention owing to their fewer interfacial defects caused by the agglomeration of fillers. Continuous oxide films with a preferred orientation can play a significant role in enhancing energy storage. The challenge is to prepare large-sized, freestanding, single-crystal, ferroelectric oxide films and to combine them with polymers. In this work, a well-developed water-dissolvent process was used to transfer millimeter-sized (100)-oriented BaTiO3 (BTO) films. Poly(vinylidene fluoride) (PVDF)-based heterojunctions sandwiched with the single-crystal films were synthesized via the transferring process and an optimized hot-pressing technique. By virtue of high ion displacement polarization and inhibited conductive path formation of single-crystal BTO films, the energy storage density and efficiency of BTO/PVDF heterojunctions reach 1.56 J cm-3 and 71.2% at a low electric field of 120 MV m-1, which are much higher than those of pure PVDF and BTO nanoparticles/PVDF composite films, respectively. A finite-element simulation was employed to further confirm the experimental results. This work provides an effective approach to enhance energy storage properties in various polymer-based composites and opens the door to advanced dielectric capacitors.
RESUMO
Obtaining small, fast, and energy-efficient spintronic devices requires a new way of manipulating spin states in an effective manner. Here, a prototype photovoltaic spintronic device with a p-n junction Si wafer is proposed which generates photo-induced electrons and changes the ferromagnetism by interfacial charge doping. A ferromagnetic resonance field change of 48.965 mT and 11.306 mT is achieved in Co and CoFeB thin films under sunlight illumination, respectively. The transient reflection (TR) analysis and the first principles calculation reveal the photovoltaic electrons that are doped into the magnetic layer and alter its Fermi level, correspondingly. This finding provides a new method of magnetism modulation and demonstrates a solar-driven spintronic device with abundant energy supply, which may further expand the landscape of spintronics research.