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1.
Nat Commun ; 15(1): 4113, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750029

RESUMO

Stretchable phosphorescence materials potentially enable applications in diverse advanced fields in wearable electronics. However, achieving room-temperature phosphorescence materials simultaneously featuring long-lived emission and good stretchability is challenging because it is hard to balance the rigidity and flexibility in the same polymer. Here we present a multiphase engineering for obtaining stretchable phosphorescent materials by combining stiffness and softness simultaneously in well-designed block copolymers. Due to the microphase separation, copolymers demonstrate an intrinsic stretchability of 712%, maintaining an ultralong phosphorescence lifetime of up to 981.11 ms. This multiphase engineering is generally applicable to a series of binary and ternary initiator systems with color-tunable phosphorescence in the visible range. Moreover, these copolymers enable multi-level volumetric data encryption and stretchable afterglow display. This work provides a fundamental understanding of the nanostructures and material properties for designing stretchable materials and extends the potential of phosphorescence polymers.

2.
Nanotechnology ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701761

RESUMO

The decay rate of charge in the friction layer is one of the key factors affecting the output performance of triboelectric nanogenerators (TENG). Reducing the decay rate of the triboelectric charge can increase the charge-carrying capacity of the friction layer and improve the output current and voltage of the TENG. This makes a friction generator more suitable for discontinuous driving environments. In contrast, increasing the decay rate of the charge in the friction layer can greatly improve the recovery time of the device, although it reduces the output performance of the generator. This is conducive to the application of friction generator in the field of sensors. In this study, polystyrene (PS) and carbon nanotubes (CNTs) were added to polyvinylidene fluoride (PVDF) nanofibers to adjust the charge decay time in the friction layer, thereby regulating the output performance of the friction generator and sensor. When the amount of added PS in the PVDF nanofiber reached 20%, the charge density on the friction surface increased by 1.9 times, and the charge decay time decreased by 64 times; when 0.1 wt% CNTs were added in the PVDF nanofiber, the charge decay time increased by more than 10 times. The former is more conducive to improving the power generation performance of the TENG, and the latter significantly improves the stability and repeatability of TENG-based sensors. .

3.
Nanomaterials (Basel) ; 14(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38727392

RESUMO

Lead-cooled fast reactors exhibit strong inherent safety performance and good economic features, while material degradation due to corrosion and irradiation is still challenging. Oxide dispersion-strengthened steels are one of the promising candidates for fuel cladding materials. The effects of both irradiation and corrosion on ODS steel need to be further studied. In this work, MX-ODS steel was irradiated by Fe ions at 500 °C up to 46 dpa. Later, the as-received specimen and the irradiated specimen were used to conduct corrosion tests in oxygen-saturated Pb at 550 °C for 1 h. In the as-received specimen, discontinuous oxides penetrated by Pb and Pb in contact with steel matrix were observed, demonstrating unsatisfactory corrosion resistance of the material. However, in the irradiated specimen after corrosion experiment, a protective oxide layer formed and prevented Pb attack. The oxidation behavior differences between the two specimens can be attributed to the defects produced by irradiation and the structural discrepancy in oxides caused by the formation process. A possible mechanism of irradiation on the corrosion is discussed. In the as-received specimen, Fe atoms loss led to voids in the oxides, and lead penetrated the oxides through these voids. In the irradiated specimen, defects left by previous irradiation helped to form a more uniform oxide layer. The adhesive outer magnetite oxide and the Fe ions generated from where grain boundary oxidation developed retarded the presence of voids and made the oxide layer protective.

4.
Appl Radiat Isot ; 207: 111249, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38428203

RESUMO

The 71Ga(n,γ)72Ga reaction-based epithermal neutron flux detectors are novel instruments developed to measure the epithermal neutron flux of boron neutron capture therapy (BNCT) treatment beams. In this study, a spherical epithermal neutron flux detector using 71Ga(n,γ)72Ga reaction was prototyped. The performance of the detector was experimentally evaluated at an accelerator-based BNCT (AB-BNCT) device developed by Lanzhou University, China. Based on the experimental results and related analysis, we demonstrated that the detector is a reliable tool for the quality assurance of BNCT treatment beams.


Assuntos
Terapia por Captura de Nêutron de Boro , Humanos , Terapia por Captura de Nêutron de Boro/métodos , Nêutrons , Dosagem Radioterapêutica , Raios gama , Método de Monte Carlo
5.
Med Phys ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38299670

RESUMO

BACKGROUND: In boron neutron capture therapy (BNCT)-a form of binary radiotherapy-the primary challenge in treatment planning systems for dose calculations arises from the time-consuming nature of the Monte Carlo (MC) method. Recent progress, including the use of neural networks (NN), has been made to accelerate BNCT dose calculations. However, this approach may result in significant dose errors in both the tumor and the skin, with the latter being a critical organ in BNCT. Furthermore, owing to the lack of physical processes in purely NN-based approaches, their reliability for clinical dose calculations in BNCT is questionable. PURPOSE: In this study, a physically constrained MC-NN (PCMC-NN) coupling algorithm is proposed to achieve fast and accurate computation of the BNCT three-dimensional (3D) therapeutic dose distribution. This approach synergizes the high precision of the MC method with the speed of the NN and utilizes physical conservation laws to constrain the coupling process. It addresses the time-consuming issue of the traditional MC method while reducing dose errors. METHODS: Clinical data were collected from 113 glioblastoma patients. For each patient, the 3D dose distributions for both the coarse and detailed dose grids were calculated using the MC code PHITS. Among these patients, the data from 14 patients were allocated to the test set, 9 to the validation set, and the remaining to the training set. A neural network, 3D-Unet, was built based on the coarse grid dose and patient CT information to enable fast and accurate computation of the 3D detailed grid dose distribution of BNCT. RESULTS: Statistical evaluations, including relative deviation, dose deviation, mean absolute error (MAE), and mean absolute percentage error (MAPE) were conducted. Our findings suggested that the PCMC-NN algorithm substantially outperformed the traditional NN and interpolation methods. Furthermore, the proposed algorithm significantly reduced errors, particularly in the skin and GTV, and improved computational accuracy (hereinafter referred to simply as 'accuracy') with a MAPE range of 1.6%-4.0% and a maximum MAE of 0.3 Gy (IsoE) for different organs. The dose-volume histograms generated by the PCMC-NN aligned well with those obtained from the MC method, further validating its accuracy. CONCLUSIONS: The PCMC-NN algorithm enhanced the speed and accuracy of BNCT dose calculations by combining the MC method with the NN algorithm. This indicates the significant potential of the proposed algorithm for clinical applications in optimizing treatment planning.

6.
ACS Appl Mater Interfaces ; 16(3): 3901-3910, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38206311

RESUMO

Achieving both high sensitivity and wide detecting range is significant for the applications of triboelectric nanogenerator-based self-powered pressure sensors (TPSs). However, most of the previous designs with high sensitivity usually struggle in a narrow pressure detection range (<30 kPa) while expanding the detection range normally sacrifices the sensitivity. To overcome this well-known obstacle, herein, piezopotential enhanced triboelectric effect realized by a rationally designed PDMS/ZnO NWs hierarchical wrinkle structure was exploited to develop a TPS (PETPS) with both high sensitivity and wide detecting range. In this PETPS design, the piezopotential derived from the deformation of ZnO NWs enhances its tribo-charge transferring ability; meanwhile, the hierarchical structure helps to establish a dynamically self-adjustable contact area. Benefiting from these advantages, the PETPS simultaneously achieves high sensitivity (0.26 nC cm-2 kPa-1 from 1 to 25 kPa, and 0.02 nC cm-2 kPa-1 from 25 to 476 kPa), fast response (46 ms), wide sensing range (1 to 476 kPa), and good stability (over 4000 cycles). In addition, the output charge density that is independent of the speed rate of driven force was adopted as the sensing signal of PETPS to replace the commonly used peak voltage/current values, enabling it more adaptive to accurately detect pressure variation in real applications.

7.
Appl Radiat Isot ; 205: 111184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38215645

RESUMO

Boron neutron capture therapy (BNCT) combines neutron irradiation with boron compounds that are selectively uptaken by tumor cells. Boronophenylalanine (BPA) is a boron compound used to treat malignant brain tumors. The determination of boron concentration in cells is of great relevance to the field of BNCT. This study was designed to develop a novel method for simultaneously measuring the uptake of BPA by U87 and U251 cells (two brain tumor cell lines) and number of cells using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The results revealed a linear correlation between phosphorus intensity and the numbers of U87 and U251 cells, with correlation coefficients (R2) of 0.9995 and 0.9994, respectively. High accuracy and reliability of phosphorus concentration standard curve were also found. Using this new method, we found that BPA had no significant effect on phosphorus concentration in either U87 or U251 cells. However, BPA increased the boron concentration in U87 and U251 cells in a concentration-dependent manner, with the boron concentration in U87 cells being higher than that in U251 cells. In both U87 and U251 cells, boron was mainly distributed in the cytoplasm and nucleus, accounting for 85% and 13% of the total boron uptake by U87 cells and 86% and 11% of the total boron uptake by U251 cells, respectively. In the U87 and U251 cell-derived xenograft (CDX) animal model, tumor exhibited higher boron concentration values than blood, heart, liver, lung, and brain, with a tumor/blood ratio of 2.87 for U87 cells and 3.11 for U251 cells, respectively. These results suggest that the phosphorus concentration in U87 and U251 cells can represent the number of cells and BPA is easily uptaken by tumor cells as well as in tumor tissue.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias Encefálicas , Animais , Humanos , Espectrofotometria Atômica , Boro , Reprodutibilidade dos Testes , Neoplasias Encefálicas/radioterapia , Encéfalo , Compostos de Boro , Fósforo , Terapia por Captura de Nêutron de Boro/métodos
8.
Clinics (Sao Paulo) ; 79: 100314, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38219533

RESUMO

OBJECTIVE: circCPA4 has been defined to be an oncogenic gene. This study examined whether circCPA4 regulates Prostate Cancer (PC) development and revealed its molecular mechanism. METHODS: PC tissues and PC cell lines were collected, in which circCPA4/miR-491-5p/SHOC2 levels were evaluated by RT-qPCR and immunoblot. Colony formation assay and EdU assay assessed cell proliferation, flow cytometry measured apoptosis, and Transwell assessed invasion and migration. Ki-67, cleaved caspase-3, E-cadherin, and N-cadherin were evaluated by immunoblot. Based on the luciferase reporter assay and RIP assay the authors investigated the targeting relationship between circCPA4/miR-491-5p/SHOC2. The effect of circCPA4 on tumor growth was evaluated by xenotransplantation in nude mice. RESULTS: circCPA4 and SHOC2 levels were abundant while miR-491-5p expression was low in PC. Loss of circCPA4 decreased the proliferation and EdU-positive rate of PC cells, enhanced apoptosis, and inhibited invasion, migration, and EMT. Upregulation of circCPA4 forced the malignant behaviors of PC cells, and this promotion could be abolished when miR-491-5p was overexpressed or SHOC2 was silenced. CircCAP4 competitively decoyed miR-491-5p mediating SHOC2 expression. circCAP4 suppression inhibited PC tumor growth. CONCLUSION: circCAP4 acts as a novel oncogenic factor in PC, accelerating the malignant behavior of PC cells via miR-491-5p/SHOC2 interaction. This novel ceRNA axis may be a potential target for PC drug development and targeted therapy in the future.


Assuntos
MicroRNAs , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Retroalimentação , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
9.
Adv Mater ; 36(18): e2310663, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38267010

RESUMO

Organic phosphorescent scintillating materials have shown great potential for applications in radiography and radiation detection due to their efficient utilization of excitons. However, revealing the relationship between molecule stacking and the phosphorescent radioluminescence of scintillators is still challenging. This study reports on two phenothiazine derivatives with polymorphism-dependent phosphorescence radioluminescence. The experiments reveal that molecule stacking significantly affects the non-radiation decay of the triplet excitons of scintillators, which further determines the phosphorescence scintillation performance under X-ray irradiation. These phosphorescent scintillators exhibit high radio stability and have a low detection limit of 278 nGys-1. Additionally, the potential application of these scintillators in X-ray radiography, based on their X-ray excited radioluminescence properties, is demonstrated. These findings provide a guideline for obtaining high-performance phosphorescent scintillating materials by shedding light on the effect of crystal packing on the radioluminescence of organic molecules.

10.
Chem Biol Drug Des ; 103(1): e14363, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37793997

RESUMO

Hepatocellular carcinoma (HCC) is a life-threatening disease for which there is no cure. Traditional Chinese medicine is a treasure trove of Medicinals that has been used for thousands of years. In China, the traditional herb pair, Curcumae Rhizoma and Sparganii Rhizoma (CR-SR) represent a classic herbal combination used for the treatment of HCC. However, the drug targets and pharmacological mechanism of action of CR-SR in the treatment of HCC are unclear. To address this, we screened the active components and drug targets of CR-SR from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database and a high-throughput experiment- and reference-guided database of traditional Chinese medicines (HERB database). Combined with the weighted co-expression network analysis of dataset GSE76427, we constructed an active component-target-disease regulatory network. It was found that CR-SR's active components for HCC treatment included trans-gondoic acid, beta-sitosterol, stigmasterol, hederagenin, and formononetin. These compounds specifically targeted the genes Estrogen Receptor 1 (ESR1), Cyclin A2 (CCNA2), Checkpoint Kinase 1 (CHEK1), and Nuclear Receptor Coactivator 2 (NCOA2). ESR1, CCNA2, and CHEK1 genes showed significant differences in survival prognosis, expression levels, and statistical significance during the pathological stage. Moreover, their high affinity for formononetin was determined through molecular docking analysis. Cell assays and high-throughput sequencing were performed to reveal that the inhibitory effect of formononetin on HepG2 cell proliferation was related to hepatocyte metabolism and cell cycle regulation-related pathways. This study provides insights into potential HCC treatments.


Assuntos
Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas , Isoflavonas , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Farmacologia em Rede , Simulação de Acoplamento Molecular , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
11.
Clinics ; 79: 100314, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528431

RESUMO

ABSTRACT Objective: circCPA4 has been defined to be an oncogenic gene. This study examined whether circCPA4 regulates Prostate Cancer (PC) development and revealed its molecular mechanism. Methods: PC tissues and PC cell lines were collected, in which circCPA4/miR-491-5p/SHOC2 levels were evaluated by RT-qPCR and immunoblot. Colony formation assay and EdU assay assessed cell proliferation, flow cytometry measured apoptosis, and Transwell assessed invasion and migration. Ki-67, cleaved caspase-3, E-cadherin, and N-cadherin were evaluated by immunoblot. Based on the luciferase reporter assay and RIP assay the authors investigated the targeting relationship between circCPA4/miR-491-5p/SHOC2. The effect of circCPA4 on tumor growth was evaluated by xenotransplantation in nude mice. Results: circCPA4 and SHOC2 levels were abundant while miR-491-5p expression was low in PC. Loss of circCPA4 decreased the proliferation and EdU-positive rate of PC cells, enhanced apoptosis, and inhibited invasion, migration, and EMT. Upregulation of circCPA4 forced the malignant behaviors of PC cells, and this promotion could be abolished when miR-491-5p was overexpressed or SHOC2 was silenced. CircCAP4 competitively decoyed miR-491-5p mediating SHOC2 expression. circCAP4 suppression inhibited PC tumor growth. Conclusion: circCAP4 acts as a novel oncogenic factor in PC, accelerating the malignant behavior of PC cells via miR-491-5p/SHOC2 interaction. This novel ceRNA axis may be a potential target for PC drug development and targeted therapy in the future.

12.
J Med Virol ; 95(11): e29244, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38010649

RESUMO

Cervical cancers are the fourth most common and most deadly cancer in women worldwide. Despite being a tremendous public health burden, few novel approaches to improve care for these malignancies have been introduced. We discuss the potential for proliferating cell nuclear antigen (PCNA) inhibition to address this need as well as the advantages and disadvantages for compounds that can therapeutically inhibit PCNA with a specific focus on cervical cancer.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Antígeno Nuclear de Célula em Proliferação
13.
Integr Zool ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37897119

RESUMO

The marine environment presents challenges for wound healing in cetaceans, despite their remarkable recovery abilities with minimal infections or complications. However, the molecular mechanism underlying this efficient wound healing remains underexplored. To better understand the molecular mechanisms behind wound healing in cetaceans, we investigated the evolutionary patterns of 37 wound healing-related genes in representative mammals. We found wound healing-related genes experience adaptive evolution in cetaceans: (1) Three extrinsic coagulation pathway-related genes-tissue factor (F3), coagulation factor VII (F7), and coagulation factor X (F10)-are subject to positive selection in cetaceans, which might promote efficient hemostasis after injury; positive selection in transforming growth factor-beta 2 (TGF-ß2), transforming growth factor-beta 3 (TGF-ß3), and platelet-derived growth factor D (PDGFD), which play immunological roles in wound healing, may help cetaceans enhance inflammatory response and tissue debridement. (2) Coagulation factor XII (F12) is the initiation factor in the intrinsic coagulation pathway. It had a premature stop codon mutation and was subjected to selective stress relaxation in cetaceans, suggesting that the early termination of F12 may help cetaceans avoid the risk of vascular blockage during diving. (3) Fibrinogen alpha chain (FGA) and FIII, which were detected to contain the specific amino acid substitutions in marine mammals, indicating similar evolutionary mechanisms might exist among marine mammals to maintain strong wound-healing ability. Thus, our research provides further impetus to study the evolution of the wound healing system in cetaceans and other marine mammals, extending knowledge of preventing coagulation disorder and atherosclerosis in humans.

14.
Exp Ther Med ; 26(3): 450, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37614418

RESUMO

Atherosclerosis (AS) is a type of chronic inflammatory disease and the main pathological basis of cardiovascular and cerebrovascular diseases, which seriously threaten the health of patients. The dual specificity phosphatase 12 (DUSP12) protein is known as regulator of inflammatory diseases. Nonetheless, at present, there are only a few reports on the regulatory role of DUSP12 in AS. Human umbilical vein endothelial cells (HUVECs) were induced using oxidized low-density lipoprotein (ox-LDL). Subsequently, cell transfection experiments were performed to overexpress DUSP12 in ox-LDL-induced HUVECs. Cell Counting Kit-8, TUNEL western blotting, 2',7'-dichlorofluorescein diacetate assays, ELISA and other techniques were used to measure cell viability, apoptosis, inflammation, oxidative stress and endothelial function-related indicators. Subsequently, the relationship between DUSP12 and Forkhead box P1 (FOXP1) was predicted using the JASPAR database and verified using luciferase reporter and chromatin immunoprecipitation assays. Finally, the regulatory mechanism was investigated by simultaneously overexpressing DUSP12 and knocking down FOXP1 in ox-LDL-induced HUVECs and MAP3K5-related proteins of the DUSP12 downstream pathway were measured by western blotting. The expression of DUSP12 in ox-LDL-induced HUVECs was significantly decreased. Overexpression of DUSP12 inhibited apoptosis, inflammation and oxidative stress damage and alleviated endothelial dysfunction in ox-LDL-induced HUVECs. FOXP1 promoted the transcription of DUSP12. Moreover, FOXP1 alleviated ox-LDL-induced apoptosis, inflammation and oxidative stress damage in HUVECs by regulating the expression of DUSP12, probably acting through the MAP3K5 pathway. Collectively, the present study revealed that FOXP1-induced DUSP12 alleviated vascular endothelial cell inflammation and oxidative stress injury in ox-LDL-induced HUVECs via the MAP3K5 signaling pathway, which might shed novel insights into the targeted treatment for AS in the clinic.

15.
Cell Chem Biol ; 30(10): 1235-1247.e6, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37531956

RESUMO

Targeting transcription replication conflicts, a major source of endogenous DNA double-stranded breaks and genomic instability could have important anticancer therapeutic implications. Proliferating cell nuclear antigen (PCNA) is critical to DNA replication and repair processes. Through a rational drug design approach, we identified a small molecule PCNA inhibitor, AOH1996, which selectively kills cancer cells. AOH1996 enhances the interaction between PCNA and the largest subunit of RNA polymerase II, RPB1, and dissociates PCNA from actively transcribed chromatin regions, while inducing DNA double-stranded breaks in a transcription-dependent manner. Attenuation of RPB1 interaction with PCNA, by a point mutation in RPB1's PCNA-binding region, confers resistance to AOH1996. Orally administrable and metabolically stable, AOH1996 suppresses tumor growth as a monotherapy or as a combination treatment but causes no discernable side effects. Inhibitors of transcription replication conflict resolution may provide a new and unique therapeutic avenue for exploiting this cancer-selective vulnerability.


Assuntos
Cromatina , Neoplasias , Humanos , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/química , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ligação Proteica , Neoplasias/tratamento farmacológico , DNA , Replicação do DNA
16.
Genes (Basel) ; 14(7)2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37510250

RESUMO

This article reviews the currently used therapeutic strategies to target DNA replication stress for cancer treatment in the clinic, highlighting their effectiveness and limitations due to toxicity and drug resistance. Cancer cells experience enhanced spontaneous DNA damage due to compromised DNA replication machinery, elevated levels of reactive oxygen species, loss of tumor suppressor genes, and/or constitutive activation of oncogenes. Consequently, these cells are addicted to DNA damage response signaling pathways and repair machinery to maintain genome stability and support survival and proliferation. Chemotherapeutic drugs exploit this genetic instability by inducing additional DNA damage to overwhelm the repair system in cancer cells. However, the clinical use of DNA-damaging agents is limited by their toxicity and drug resistance often arises. To address these issues, the article discusses a potential strategy to target the cancer-associated isoform of proliferating cell nuclear antigen (caPCNA), which plays a central role in the DNA replication and damage response network. Small molecule and peptide agents that specifically target caPCNA can selectively target cancer cells without significant toxicity to normal cells or experimental animals.


Assuntos
Neoplasias , Animais , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Replicação do DNA , Dano ao DNA , Oncogenes
17.
J Neurochem ; 166(2): 280-293, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37309616

RESUMO

Neuroinflammation has been reported to be associated with white matter injury (WMI) after subarachnoid hemorrhage (SAH). As the main resident immune cells of the brain, microglia can be activated into proinflammatory and anti-inflammatory phenotypes. Toll-like receptor 4 (TLR4), expressed on the surface of the microglia, plays a key role in microglial inflammation. However, the relationship between TLR4, microglial polarization, and WMI following SAH remains unclear. In this study, a total of 121 male adult C57BL/6 wild-type (WT) mice, 20 WT mice at postnatal day 1 (P1), and 41 male adult TLR4 gene knockout (TLR4-/-) mice were used to investigate the potential role of TLR4-induced microglial polarization in early WMI after SAH by radiological, histological, microstructural, transcriptional, and cytological evidence. The results indicated that microglial inflammation was associated with myelin loss and axon damage, shown as a decrease in myelin basic protein (MBP), as well as increase in degraded myelin basic protein (dMBP) and amyloid precursor protein (APP). Gene knockout of TLR4 revised microglial polarization toward the anti-inflammatory phenotype and protected the white matter at an early phase after SAH (24 h), as shown through reduction of toxic metabolites, preservation of myelin, reductions in APP accumulation, reductions in white matter T2 hyperintensity, and increases in FA values. Cocultures of microglia and oligodendrocytes, the cells responsible for myelin production and maintenance, were established to further elucidate the relationship between microglial polarization and WMI. In vitro, TLR4 inhibition decreased the expression of microglial MyD88 and phosphorylated NF-κB, thereby inhibiting M1 polarization and mitigating inflammation. Decrease in TLR4 in the microglia increased preservation of neighboring oligodendrocytes. In conclusion, microglial inflammation has dual effects on early WMI after experimental SAH. Future explorations on more clinically relevant methods for modulating neuroinflammation are warranted to combat stroke with both WMI and gray matter destruction.


Assuntos
Lesões Encefálicas , Hemorragia Subaracnóidea , Substância Branca , Camundongos , Animais , Masculino , Microglia/metabolismo , Hemorragia Subaracnóidea/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteína Básica da Mielina/metabolismo , Proteína Básica da Mielina/farmacologia , Substância Branca/patologia , Doenças Neuroinflamatórias , Camundongos Endogâmicos C57BL , Inflamação/patologia , Lesões Encefálicas/patologia , Anti-Inflamatórios/farmacologia
18.
Adv Mater ; 35(36): e2210489, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37390483

RESUMO

Achieving multicolor organic afterglow materials with narrowband emission and high color purity is important in various optoelectronic fields but remains a great challenge. Here, an efficient strategy is presented to obtain narrowband organic afterglow materials via Förster resonance energy transfer from long-lived phosphorescence donors to narrowband fluorescence acceptors in a polyvinyl alcohol matrix. The resulting materials exhibit narrowband emission with a full width at half maximum (FWHM) as small as 23 nm and the longest lifetime of 721.22 ms. Meanwhile, by pairing the appropriate donors and acceptors, multicolor and high color purity afterglow ranging from green to red with the maximum photoluminescence quantum yield of 67.1% are achieved. Moreover, given their long luminescence lifetime, high color purity, and flexibility, the potential applications are demonstrated in high-resolution afterglow displays and dynamic and quick information identification in low-light conditions. This work provides a facile approach for developing multicolor and narrowband afterglow materials as well as expands the features of organic afterglow.

19.
Heliyon ; 9(5): e16203, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37251901

RESUMO

The accelerator-driven subcritical system has a strong transmutation ability and high inherent safety, and it is internationally recognized as the most promising long-life nuclear waste disposal device. This study involves the construction of a Visual Hydraulic ExperimentaL Platform (VHELP) for the purpose of evaluating the applicability of Reynolds-averaged Navier-Stokes (RANS) models and analyzing the pressure distribution within the fuel bundle channel of China initiative accelerator-driven system (CiADS). Measurements of thirty differential pressures in edge subchannels within a 19-pin wire-wrapped fuel bundle channel were obtained under different conditions using deionized water. The pressure distribution in the fuel bundle channel at Reynolds numbers of 5000, 7500, 10,000, 12,500, and 15,000 was simulated using Fluent. The results show that RANS models obtained accurate results, and the shear stress transport k-ω model provided the most accurate prediction of the pressure distribution. The difference between the results of the Shear stress transport (SST) k-ω model and experimental data was the smallest, and the maximum difference was ±5.57%. Moreover, the error between the experimental data and numerical results of the axial differential pressure was smaller than that of the transverse differential pressure. The pressure periodicity in axial and transverse directions (one pitch) and a relatively three-dimensional pressure measurements were studied. The static pressure fluctuated and decreased periodically as the z-axis coordinate increased. These results can facilitate research on the cross-flow characteristics of liquid metal-cooled fast reactors.

20.
Nat Commun ; 14(1): 2943, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221237

RESUMO

Cancer immunotherapy is revolutionizing oncology. The marriage of nanotechnology and immunotherapy offers a great opportunity to amplify antitumor immune response in a safe and effective manner. Here, electrochemically active Shewanella oneidensis MR-1 can be applied to produce FDA-approved Prussian blue nanoparticles on a large-scale. We present a mitochondria-targeting nanoplatform, MiBaMc, which consists of Prussian blue decorated bacteria membrane fragments having further modifications with chlorin e6 and triphenylphosphine. We find that MiBaMc specifically targets mitochondria and induces amplified photo-damages and immunogenic cell death of tumor cells under light irradiation. The released tumor antigens subsequently promote the maturation of dendritic cells in tumor-draining lymph nodes, eliciting T cell-mediated immune response. In two tumor-bearing mouse models using female mice, MiBaMc triggered phototherapy synergizes with anti-PDL1 blocking antibody for enhanced tumor inhibition. Collectively, the present study demonstrates biological precipitation synthetic strategy of targeted nanoparticles holds great potential for the preparation of microbial membrane-based nanoplatforms to boost antitumor immunity.


Assuntos
Ferrocianetos , Inibidores de Checkpoint Imunológico , Feminino , Animais , Camundongos , Anticorpos Bloqueadores , Imunoterapia
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