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Cancer cells often overexpress CD47, which triggers the inhibitory receptor SIRPα expressed on macrophages, to elude phagocytosis and antitumor immunity. Pharmacological blockade of CD47 or SIRPα is showing promise as anticancer therapy, although CD47 blockade has been associated with hematological toxicities that may reflect its broad expression pattern on normal cells. Here we found that, in addition to triggering SIRPα, CD47 suppressed phagocytosis by a SIRPα-independent mechanism. This mechanism prevented phagocytosis initiated by the pro-phagocytic ligand, SLAMF7, on tumor cells, due to a cis interaction between CD47 and SLAMF7. The CD47-SLAMF7 interaction was disrupted by CD47 blockade and by a first-in-class agonist SLAMF7 antibody, but not by SIRPα blockade, thereby promoting antitumor immunity. Hence, CD47 suppresses phagocytosis not only by engaging SIRPα, but also by masking cell-intrinsic pro-phagocytic ligands on tumor cells and knowledge of this mechanism may influence the decision between CD47 blockade or SIRPα blockade for therapeutic purposes.
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Antígeno CD47 , Neoplasias , Evasão Tumoral , Humanos , Antígenos de Diferenciação/metabolismo , Antígenos de Diferenciação/uso terapêutico , Ligantes , Macrófagos , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/patologia , Fagocitose , Animais , CamundongosRESUMO
Invariant natural killer T cells (iNKT cells) develop through an incompletely understood process that requires positive selection by CD4+CD8+ double-positive thymocytes and SLAM family receptors (SFRs). Here we found that SFRs promoted the development of iNKT cells by reducing the strength of the T cell antigen receptor (TCR) signal after positive selection. This effect improved the survival of iNKT cells and their responses to antigen. Loss of SFRs upregulated the expression of inhibitory receptors, including PD-1, on iNKT cells to mitigate the deleterious effect of SFR deficiency. The role of SFRs could be mimicked by expression of SLAMF6 alone in SFR-deficient mice, and this involved the adaptor SAP-kinase Fyn complex and the phosphatase SHP-1. Thus, SFRs foster iNKT cell development by attenuating TCR signal strength after positive selection.
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Células T Matadoras Naturais/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Família de Moléculas de Sinalização da Ativação Linfocitária/fisiologia , Animais , Proliferação de Células , Sobrevivência Celular , Receptores Coestimuladores e Inibidores de Linfócitos T/metabolismo , Humanos , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária/genética , Família de Moléculas de Sinalização da Ativação Linfocitária/genética , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismoRESUMO
The angular optical trap (AOT) is a powerful instrument for measuring the torsional and rotational properties of a biological molecule. Thus far, AOT studies of DNA torsional mechanics have been carried out using a high numerical aperture oil-immersion objective, which permits strong trapping but inevitably introduces spherical aberrations due to the glass-aqueous interface. However, the impact of these aberrations on torque measurements is not fully understood experimentally, partly due to a lack of theoretical guidance. Here, we present a numerical platform based on the finite element method to calculate forces and torques on a trapped quartz cylinder. We have also developed a new experimental method to accurately determine the shift in the trapping position due to the spherical aberrations by using a DNA molecule as a distance ruler. We found that the calculated and measured focal shift ratios are in good agreement. We further determined how the angular trap stiffness depends on the trap height and the cylinder displacement from the trap center and found full agreement between predictions and measurements. As a further verification of the methodology, we showed that DNA torsional properties, which are intrinsic to DNA, could be determined robustly under different trap heights and cylinder displacements. Thus, this work has laid both a theoretical and experimental framework that can be readily extended to investigate the trapping forces and torques exerted on particles with arbitrary shapes and optical properties.
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DNA , Pinças Ópticas , Torque , DNA/química , Análise de Elementos Finitos , Torção Mecânica , Fenômenos ÓpticosRESUMO
Despite progress in cancer immunotherapy, ovarian cancer (OC) prognosis continues to be disappointing. Recent studies have shed light on how not just tumour cells, but also the complex tumour microenvironment, contribute to this unfavourable outcome of OC immunotherapy. The complexities of the immune microenvironment categorize OC as a 'cold tumour'. Nonetheless, understanding the precise mechanisms through which the microenvironment influences the effectiveness of OC immunotherapy remains an ongoing scientific endeavour. This review primarily aims to dissect the inherent characteristics and behaviours of diverse cells within the immune microenvironment, along with an exploration into its reprogramming and metabolic changes. It is expected that these insights will elucidate the operational dynamics of the immune microenvironment in OC and lay a theoretical groundwork for improving the efficacy of immunotherapy in OC management.
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Imunoterapia , Neoplasias Ovarianas , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Feminino , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/terapia , Imunoterapia/métodos , Animais , Resultado do TratamentoRESUMO
An iron/chromium system (Fe(OAc)2, CpCr(CO)3H) catalyzes the preparation of ß,γ- or γ,δ-unsaturated amides from 1,4,2-dioxazol-5-ones. An acyl nitrenoid iron complex seems likely to be responsible for C-H activation. A cascade of three H⢠transfer steps appears to be involved: (i) the abstraction of H⢠from a remote C-H bond by the nitrenoid N, (ii) the transfer of H⢠from Cr to N, and (iii) the abstraction of H⢠from a radical substituent by the Crâ¢. The observed kinetic isotope effects are consistent with the proposed mechanism if nitrenoid formation is the rate-determining step. The Fe/Cr catalysts can also desaturate substituted 1,4,2-dioxazol-5-ones to 3,5-dienamides.
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Lead-free dielectric capacitors have attracted significant research interest for high-power applications due to their environmental benefits and ability to meet the demanding performance requirements of electronic devices. However, the development of lead-free ceramic dielectrics with outstanding energy storage performance remains a challenge. In this study, environmentally friendly ceramic dielectrics with sandwich structures are designed and fabricated to improve energy storage performance via the synergistic effect of different dielectrics. The chemical compositions of the outer and middle layers of the sandwich structure are 0.35BiFeO3 -0.65SrTiO3 and Bi0.39 Na0.36 Sr0.25 TiO3 , respectively. The experimental and theoretical simulation results demonstrate that the breakdown strength is over 700 kV cm-1 for prepare sandwich structure ceramics. As a result, an ultrahigh recoverable energy storage density of 9.05 J cm-3 and a near-ideal energy storage efficiency of 97% are simultaneously achieved under 710 kV cm-1 . Furthermore, the energy storage efficiency maintains high values (≥ 96%) within 1-100 Hz and the power density as high as 188 MW cm-3 under 400 kV cm-1 . These results indicate that the designed lead-free ceramics with a sandwich structure possess superior comprehensive energy storage performance, making them promising lead-free candidates in the energy storage field.
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Glioma is a primary brain tumor that grows quickly, has an unfavorable prognosis, and can spread intracerebrally. Glioma cells rely on glucose as the major energy source, and glycolysis plays a critical role in tumorigenesis and progression. Substrate utilization shifts throughout glioma progression to facilitate energy generation and biomass accumulation. This metabolic reprogramming promotes glioma cell proliferation and metastasis and ultimately decreases the efficacy of conventional treatments. Non-coding RNAs (ncRNAs) are involved in several glucose metabolism pathways during tumor initiation and progression. These RNAs influence cell viability and glucose metabolism by modulating the expression of key genes of the glycolytic pathway. They can directly or indirectly affect glycolysis in glioma cells by influencing the transcription and post-transcriptional regulation of oncogenes and suppressor genes. In this review, we discussed the role of ncRNAs in the metabolic reprogramming of glioma cells and tumor microenvironments and their abnormal expression in the glucometabolic pathway in glioma. In addition, we consolidated the existing theoretical knowledge to facilitate the use of this emerging class of biomarkers as biological indicators and potential therapeutic targets for glioma.
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Micropterus salmoides rhabdovirus (MSRV) is one of the main pathogens of largemouth bass, leading to serious economic losses. The G protein, as the only envelope protein present on the surface of MSRV virion, contains immune-related antigenic determinants, thereby becoming the primary target for the design of MSRV vaccines. Here, we displayed the G protein on the surface of yeast cells (named EBY100/pYD1-G) and conducted a preliminary assessment of the protective efficacy of the recombinant yeast vaccine. Upon oral vaccination, a robust immune response was observed in systemic and mucosal tissue. Remarkably, following the MSRV challenge, the relative percent survival of EBY100/pYD1-G treated largemouth bass significantly increased to 66.7 %. In addition, oral administration inhibited viral replication and alleviated the pathological symptoms of MSRV-infected largemouth bass. These results suggest that EBY100/pYD1-G could be used as a potential oral vaccine against MSRV infection.
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Bass , Doenças dos Peixes , Rhabdoviridae , Animais , Saccharomyces cerevisiae , Vacinação , Proteínas Fúngicas , Vacinas SintéticasRESUMO
Cardiac inflammation contributes to heart failure (HF) induced by isoproterenol (ISO) through activating ß-adrenergic receptors (ß-AR). Recent evidence shows that myeloid differentiation factor 2 (MD2), a key protein in endotoxin-induced inflammation, mediates inflammatory heart diseases. In this study, we investigated the role of MD2 in ISO-ß-AR-induced heart injuries and HF. Mice were infused with ISO (30 mg·kg-1·d-1) via osmotic mini-pumps for 2 weeks. We showed that MD2 in cardiomyocytes and cardiac macrophages was significantly increased and activated in the heart tissues of ISO-challenged mice. Either MD2 knockout or administration of MD2 inhibitor L6H21 (10 mg/kg every 2 days, i.g.) could prevent mouse hearts from ISO-induced inflammation, remodelling and dysfunction. Bone marrow transplantation study revealed that both cardiomyocyte MD2 and bone marrow-derived macrophage MD2 contributed to ISO-induced cardiac inflammation and injuries. In ISO-treated H9c2 cardiomyocyte-like cells, neonatal rat primary cardiomyocytes and primary mouse peritoneal macrophages, MD2 knockout or pre-treatment with L6H21 (10 µM) alleviated ISO-induced inflammatory responses, and the conditioned medium from ISO-challenged macrophages promoted the hypertrophy and fibrosis in cardiomyocytes and fibroblasts. We demonstrated that ISO induced MD2 activation in cardiomyocytes via ß1-AR-cAMP-PKA-ROS signalling axis, and induced inflammatory responses in macrophages via ß2-AR-cAMP-PKA-ROS axis. This study identifies MD2 as a key inflammatory mediator and a promising therapeutic target for ISO-induced heart failure.
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Insuficiência Cardíaca , Miócitos Cardíacos , Ratos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Isoproterenol/toxicidade , Receptores Adrenérgicos beta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Macrófagos/metabolismoRESUMO
Inadequate methane production and insufficient hydrolysis-acidification activity impede the practical application of anaerobic digestion (AD) of waste activated sludge (WAS). Recently, metal-organic framework (MOF) materials attains promising capability of controlling proton/electron transfer in AD processes. This study used a typical iron-based MOF and MIL-88A(Fe) to improve the methane production via digesting WAS. These materials were prepared via a one-step hydrothermal method. The findings indicated that the addition of 150 mg MIL-88A(Fe)/g WAS VS resulted in a 57.23% increase in accumulated methane production and a 43.84% increase in daily maximum methane production. The methane production rate (Rmax) also increased from 22.25 to 29.14 mL/g VS/d. The enhanced electron transfer capacity, improved hydrolysis of WAS, boosted acetate generation, and mitigated accumulation of volatile fatty acids (VFAs) collectively contributed to the better methane yield in the MIL-88A(Fe)-added system. The significant enrichment of Methanobacterium and Methanosaeta along with the up-regulation of key methanogenesis enzyme-encoding genes jointly suggested that the CO2 reduction and methanogenesis were strengthened. Moreover, MIL-88A(Fe) stimulated the production of c-type cytochrome and e-pili, facilitating direct interspecies electron transfer (DIET) between norank-f-SC-I-84 and Methanobacterium. This study provided new solutions for improving methane production and offered insights into the mechanism of enhanced methanogenesis of AD in the presence of MIL-88A(Fe).
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Background: Paraquat (PQ) plays an important role in agricultural production due to its highly effective herbicidal effect. However, it has led to multiple organ failure in those who have been poisoned, with damage most notable in the lungs and ultimately leading to death. Because of little research has been performed at the genetic level, and therefore, the specific genetic changes caused by PQ exposure are unclear.Methods: Paraquat poisoning model was constructed in Sprague Dawley (SD) rats, and SD rats were randomly divided into Control group, paraquat (PQ) poisoning group and Anthrahydroquinone-2,6-disulfonate (AH2QDS) treatment group. Then, the data was screened and quality controlled, compared with reference genes, optimized gene structure, enriched at the gene expression level, and finally, signal pathways with significantly different gene enrichment were screened.Results: This review reports on lung tissues from paraquat-intoxicated Sprague Dawley (SD) rats that were subjected to RNA-seq, the differentially expressed genes were mainly enriched in PI3K-AKT, cGMP-PKG, MAPK, Focal adhesion and other signaling pathways.Conclusion: The signaling pathways enriched with these differentially expressed genes are summarized, and the important mechanisms mediated through these pathways in acute lung injury during paraquat poisoning are outlined to identify important targets for AH2QDS treatment of acute lung injury due to paraquat exposure, information that will be used to support a subsequent in-depth study on the mechanism of PQ action.
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Lesão Pulmonar Aguda , Paraquat , Ratos , Animais , Ratos Sprague-Dawley , Paraquat/toxicidade , RNA-Seq , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Pulmão , Transdução de Sinais , TecnologiaRESUMO
OBJECTIVE: To explore the effect of repetitive transcranial magnetic stimulation (rTMS)-assisted training on lower limb motor function in children with hemiplegic cerebral palsy (HCP). METHOD: Thirty-one children with HCP who met the inclusion criteria were selected and randomly divided into a control group (n = 16) and an experimental group (n = 15). The control group received routine rehabilitation treatment for 30 min each time, twice a day, 5 days a week for 4 weeks. Based on the control group, the experimental group received rTMS for 20 min each time, once a day, 5 days a week for 4 weeks. The outcome measures included a 10-metre walk test (10MWT), a 6-minute walk distance (6MWD) test, D- and E-zone gross motor function measurements (GMFM), the symmetry ratio of the step length and stance time and the muscle tone of the triceps surae and the hamstrings (evaluated according to the modified Ashworth scale), which were obtained in both groups of children before and after treatment. RESULTS: After training, the 10MWT (P < 0.05), 6MWD (P < 0.01), GMFM (P < 0.001) and the symmetry ratio of the step length and stance time of the two groups were significantly improved (P < 0.05), there was more of an improvement in the experimental group compared with the control group. There was no significant change in the muscle tone of the hamstrings between the two groups before and after treatment (P > 0.05). After treatment, the muscle tone of the triceps surae in the experimental group was significantly reduced (P < 0.05), but there was no significant change in the control group (P > 0.05). CONCLUSION: Repetitive TMS-assisted training can improve lower limb motor function in children with HCP.
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Paralisia Cerebral , Estimulação Magnética Transcraniana , Criança , Humanos , Hemiplegia/etiologia , Extremidade Inferior , CaminhadaRESUMO
BACKGROUND: The 8th rib cartilage was sometimes insufficient to construct a complete external helix in ear reconstruction for microtia. The aim of this study was to investigate the splicing technique of 8th rib cartilage in modified Nagata method stage I. METHODS: Between September 2022 and May 2023, 231 consecutive patients with microtia underwent auricular reconstruction with modified Nagata method stage I. Thirty-four patients with insufficient 8th rib cartilage were screened out by three-dimensional (3D) computed tomography preoperatively, who were included in the study prospectively. The 8th rib was spliced to create the external helix when fabricating the ear framework in the stage I surgery for the 34 patients. The median duration of follow-up was 12.1 months (8-15 months). RESULTS: There were no perioperative complications in our study. During follow-up, all patients had satisfying outcomes, with no inward collapse, displacement, or absorption of the spliced external helix. The splicing point was not obvious. CONCLUSIONS: It was safe and effective to splice the 8th rib cartilage for external helix of the cartilage framework in ear reconstruction for microtia.
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OBJECTIVE: To evaluate the utility of 3-dimensional computed tomography (3D CT) reconstruction in rib cartilages harvest and auricular reconstruction. METHODS: This was a retrospective study of 105 patients with microtia who underwent auricular reconstruction in our department, including 53 controls. All patients underwent chest CT scans and 52 patients in the CT group underwent rib cartilage reconstruction simultaneously. All patients' sex, age, height, and body weight were reviewed. Preoperative CT measurements included the length and width of the sixth, seventh, eighth, and ninth rib cartilages. Operative measurements included the number, amount, length and width of the costal cartilages harvested, operation time, and the amount of bleeding. RESULTS: There was no significant difference in the preoperative and operative measurements of the seventh rib. The mean age, height, and weight of the 3D CT group were significantly less than the control group. Compared with the control group, the costicartilage taken in the 3D CT group was significantly shorter in length, but there was no significant difference in the number of ribs taken. The operation time of the 3D CT group was less than the control group. CONCLUSIONS: Reconstructive 3D CT provides vivid and accurate data of costochondral volume, and is valuable for surgical timing and cartilage sculpting. With the aid of the 3D CT measurements, surgeons can make an individualized surgical planning. Unnecessary harvest of rib cartilage and surgical time are avoided by having a throughout plan before operation.
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Extensive skin graft necrosis after auricle reconstruction surgery is a thorny problem for plastic surgeons. Four unilateral microtia patients were enrolled for extensive skin graft necrosis after ear elevation surgery. Early debridement and daily dressing changes were important for preoperative preparation. Surgical treatments involved local flaps and secondary split-thickness skin graft. After 3 to 12 months of follow-up, clear surface structures and obvious auricular sulcus were shown in all 4 patients. No cartilage exposure, skin necrosis, healing impairment, or other complications were found. We attribute the cause of extensive skin graft necrosis to subcutaneous hematoma. Local skin flaps and split-thickness skin grafting can be effective treatments for such situations. The use of temporoparietal fascial flap is unnecessary when poor graft survival is caused by subcutaneous hematoma.
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Pavilhão Auricular , Necrose , Procedimentos de Cirurgia Plástica , Transplante de Pele , Retalhos Cirúrgicos , Criança , Humanos , Masculino , Microtia Congênita/cirurgia , Desbridamento , Pavilhão Auricular/cirurgia , Hematoma/cirurgia , Hematoma/etiologia , Procedimentos de Cirurgia Plástica/métodos , Complicações Pós-Operatórias/cirurgia , Terapia de Salvação/métodos , Transplante de Pele/métodosRESUMO
Lattice mismatch significantly influences microscopic transport in semiconducting devices, affecting interfacial charge behavior and device efficacy. This atomic-level disordering, often overlooked in previous research, is crucial for device efficiency and lifetime. Recent studies have highlighted emerging challenges related to lattice mismatch in perovskite solar cells, especially at heterojunctions, revealing issues like severe tensile stress, increased ion migration, and reduced carrier mobility. This review systematically discusses the effects of lattice mismatch on strain, material stability, and carrier dynamics. It also includes detailed characterizations of these phenomena and summarizes current strategies including epitaxial growth and buffer layer, as well as explores future solutions to mitigate mismatch-induced issues. We also provide the challenges and prospects for lattice mismatch, aiming to enhance the efficiency and stability of perovskite solar cells, and contribute to renewable energy technology advancements.
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In the course of our investigations of the adsorption of ions to the air-water interface, we previously reported the surprising result that doubly charged carbonate anions exhibit a stronger surface affinity than singly charged bicarbonate anions. In contrast to monovalent, weakly hydrated anions, which generally show enhanced concentrations in the interfacial region, multivalent (and strongly hydrated) anions are expected to show a much weaker surface propensity. In the present work, we use resonantly enhanced deep-UV second-harmonic generation spectroscopy to measure the Gibbs free energy of adsorption of both carbonate (CO32-) and bicarbonate (HCO3-) anions to the air-water interface. Contrasting the predictions of classical electrostatic theory and in support of our previous findings from X-ray photoelectron spectroscopy, we find that carbonate anions do indeed exhibit much stronger surface affinity than do the bicarbonate anions. Extensive computer simulations reveal that strong ion pairing of CO32- with the Na+ countercation in the interfacial region results in the formation of near-neutral agglomerate clusters, consistent with a theory of interfacial ion adsorption based on hydration free energy and capillary waves. Simulated X-ray photoelectron spectra predict a 1 eV shift in the carbonate spectra compared to that of bicarbonate, further confirming our experiments. These findings not only advance our fundamental understanding of ion adsorption chemistry but also impact important practical processes such as ocean acidification, sea-spray aerosol chemistry, and mammalian respiration physiology.
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BACKGROUNDS: HLA-B*58:01 allele was strongly associated with allopurinol induced severe cutaneous adverse drug reaction (SCAR). However, HLA-B genotype is not sufficient to predict the occurrence of allopurinol-induced SCAR. OBJECTIVE: To discover DNA methylation markers for allopurinol-induced SCAR which may improve the prediction accuracy of genetic testing. STUDY DESIGN: The study was designed as a retrospective case-control clinical study in multicenter hospitals across Taiwan, Mainland China, Malaysia and Canada. 125 cases of allopurinol-induced SCAR patients and 139 cases of allopurinol tolerant controls were enrolled in this study during 2005 to 2021. RESULTS: The results of genome-wide DNA methylation assay of 62 patients revealed that ITGB2 showed strong discriminative ability of allopurinol-induced SCAR in both HLA-B*58:01 positive and negative patients with AUC value of 0.9364 (95% CI 0.8682-1.000). In validation study, significant hypermethylation of ITGB2 were further validated in allopurinol-induced SCAR patients compared to tolerant controls, especially in those without HLA-B*58:01(AUC value of 0.8814 (95% CI 0.7121-1.000)). Additionally, the methylation levels of 2 sites on ITGB2 were associated with SCAR phenotypes. Combination of HLA-B*58:01 genotyping and ITGB2 methylation status could improve the prediction accuracy of allopurinol-induced SCAR with the AUC value up to 0.9387 (95% CI 0.9089-0.9684), while the AUC value of HLA-B*58:01 genotyping alone was 0.8557 (95% CI 0.8030-0.9083). CONCLUSIONS: Our study uncovers differentially methylated genes between allopurinol-induced SCAR patients and tolerant controls with positive or negative HLA-B*58:01 allele and provides the novel epigenetic marker that improves the prediction accuracy of genetic testing for prevention of allopurinol-induced SCAR.
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Hipersensibilidade a Drogas , Síndrome de Stevens-Johnson , Humanos , Alopurinol/efeitos adversos , Estudos Retrospectivos , Metilação de DNA , Hipersensibilidade a Drogas/epidemiologia , Antígenos HLA-B/genética , Síndrome de Stevens-Johnson/tratamento farmacológico , Síndrome de Stevens-Johnson/genéticaRESUMO
Owing to the high power density, eco-friendly, and outstanding stability, the lead-free ceramics have attracted great interest in the fields of pulsed power systems. Nevertheless, the low energy storage density of such ceramics is undoubtedly a severe problem in practical applications. To overcome this limitation, the lead-free ceramics with gradient structures are designed and fabricated using the tape-casting method herein. By optimizing the composition and distribution of the gradient-structured ceramics, the energy storage density, and efficiency can be improved simultaneously. Under a moderate electric field of 320 kV cm-1 , the value of recoverable energy storage density (Wrec ) is higher than 4 J cm-3 , and the energy storage efficiency (η) is of ≥88% for 20-5-20 and 20-10-20. Furthermore, the gradient-structured ceramics of 20-10-0-10-20 and 20-15-0-15-20 possess high applied electric field, large maximum polarization, and small remnant polarization, which give rise to ultrahigh Wrec and η on the order of ≈6.5 J cm-3 and 89-90%, respectively. In addition, the energy storage density and efficiency also exhibit excellent stability over a broad range of frequencies, temperatures, and cycling numbers. This work provides an effective strategy for improving the energy storage capability of eco-friendly ceramics.
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PbYb0.5 Nb0.5 O3 (PYN)-based ceramics, featured by their ultra-high phase-switching field and low sintering temperature (950 °C), are of great potential in exploiting dielectric ceramics with high energy storage density and low preparation cost. However, due to insufficient breakdown strength (BDS), their complete polarization-electric field (P-E) loops are difficult to be obtained. Here, to fully reveal their potential in energy storage, synergistic optimization strategy of composition design with Ba2+ substitution and microstructure engineering via hot-pressing (HP) are adopted in this work. With 2 mol% Ba2+ doping, a recoverable energy storage density (Wrec ) of 10.10 J cm-3 and a discharge energy density (Wdis ) of 8.51 J cm-3 can be obtained, supporting the superior current density (CD ) of 1391.97 A cm-2 and the outstanding power density (PD ) of 417.59 MW cm-2 . In situ characterization methods are utilized here to reveal the unique movement of the B-site ions of PYN-based ceramics under electric field, which is the key factor of the ultra-high phase-switching field. It is also confirmed that microstructure engineering can refine the grain of ceramics and improve BDS. This work strongly demonstrates the potential of PYN-based ceramics in energy storage field and plays a guiding role in the follow-up research.