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BACKGROUND: Despite significant advances in lung cancer treatment, cisplatin (DDP)-based chemotherapy remains a cornerstone for managing the disease. However, the prevalence of chemoresistance presents a major challenge, limiting its effectiveness and contributing to poor outcomes. This underscores the urgent need for novel therapeutic strategies to overcome chemoresistance and improve chemotherapy efficacy in lung cancer patients. Exploring approaches to sensitize tumors to cisplatin could enhance treatment responses and overall survival rates. METHODS AND RESULTS: Our study utilized a variety of lung cancer models, including cell lines, mouse models, and patient-derived organoids, to validate the synergistic cytotoxic effects of dihydroartemisinin (DHA) and cisplatin (DDP). When combined with DDP, we demonstrate that DHA is a promising therapeutic agent that effectively triggers ferroptosis in lung cancer cells, offering a potential strategy for overcoming chemoresistance. Mechanistically, the combination of DHA and DDP synergistically enhances ZIP14 expression, modulating iron homeostasis and upregulating oxidative stress, leading to both in vitro and in vivo ferroptosis. Notably, our findings revealed that the sequential administration of DDP followed by DHA significantly increases ZIP14 expression and induces superior therapeutic outcomes compared to the simultaneous administration or DHA followed by DDP. This observation underscores the importance of the drug administration order in optimizing treatment efficacy, providing new insights into enhancing chemotherapy response in lung cancer. CONCLUSION: Our findings suggest that combining dihydroartemisinin (DHA) with cisplatin (DDP) presents a promising strategy to overcome chemoresistance in lung cancer patients. Importantly, administering DHA during chemotherapy intervals could further optimize treatment outcomes, enhancing the overall efficacy of lung cancer chemotherapy.
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Artemisininas , Cisplatino , Ferroptose , Neoplasias Pulmonares , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Ferroptose/efeitos dos fármacos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Camundongos , Animais , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
BACKGROUND: Since its development in the 1980 s, chemical vapor deposition (CVD) diamond has found wide application in addressing various engineering challenges, owing to its outstanding characteristics, including exceptionally high hardness, excellent thermal conductivity, and remarkable stability. Notably, processing tools utilizing CVD diamond as the working material exhibit substantial potential for application in the field of mechanical manufacturing. Serving as a viable substitute for natural diamond, CVD diamond processing tools not only offer advantages in production costs but also ensure processing performance on par with natural diamonds. This presents a valuable and effective approach for achieving advanced manufacturing with high precision and low production costs. AIM OF REVIEW: The research progress of CVD diamond processing tools is comprehensively reviewed from four perspectives, encompassing the CVD process of diamonds, preparation methods, processing applications, and future development directions of CVD diamond processing tools. KEY SCIENTIFIC CONCEPTS OF REVIEW: The classification and exposition of CVD diamond deposition processes were presented. The fabrication of CVD diamond processing tools was elaborated. The machining applications of CVD diamond processing tools were then reviewed, mainly focusing on cutting and grinding processes, along with the tool wear characteristics. Finally, research challenges pertaining to CVD diamond processing tools were summarized, with insights proposed for future development opportunities and the anticipation of enhanced performance for prospective engineering applications.
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Stability-issues of organic light-emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) require further advancements, especially in pure-blue range of CIEy < 0.20, existing a dilemma between color purity and device lifetime. Though improving bond-dissociation-energy (BDE) can effectively improve material intrinsic stability, strategies to simultaneously improve BDE and photophysical performances are still lacking. Herein, it is disclosed that synergistic intramolecular non-covalent interactions (Intra-NI) can achieve not only the highest CâN BDE among blue TADF materials, but enhanced molecular-rigidity, near-unity photoluminescent quantum yields and short delayed lifetime. Pure-blue TADF-OLEDs based on proof-of-concept TADF material realize high external-quantum-efficiency and record-high LT80@500 cd m-2 of 109 h with CIEy = 0.16. Furthermore, deep-blue TADF-sensitized devices exhibit high LT80@500 cd m-2 of 81 h with CIEy = 0.10. The findings provide new insight into the critical role of Intra-NI in OLED materials and open the way to tackling vexing stability issues for developing robust pure-blue organic emitters and other functional materials.
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Accurately distinguishing tumor cells from normal cells is a key issue in tumor diagnosis, evaluation, and treatment. Fluorescence-based immunohistochemistry as the standard method faces the inherent challenges of the heterogeneity of tumor cells and the lack of big data analysis of probing images. Here, we have demonstrated a machine learning-driven imaging method for rapid pathological diagnosis of five types of cancers (breast, colon, liver, lung, and stomach) using a perovskite nanocrystal probe. After conducting the bioanalysis of survivin expression in five different cancers, high-efficiency perovskite nanocrystal probes modified with the survivin antibody can recognize the cancer tissue section at the single cell level. The tumor to normal (T/N) ratio is 10.3-fold higher than that of a conventional fluorescent probe, which can successfully differentiate between tumors and adjacent normal tissues within 10 min. The features of the fluorescence intensity and pathological texture morphology have been extracted and analyzed from 1000 fluorescence images by machine learning. The final integrated decision model makes the area under the receiver operating characteristic curve (area under the curve) value of machine learning classification of breast, colon, liver, lung, and stomach above 90% while predicting the tumor organ of 92% of positive patients. This method demonstrates a high T/N ratio probe in the precise diagnosis of multiple cancers, which will be good for improving the accuracy of surgical resection and reducing cancer mortality.
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Compostos de Cálcio , Aprendizado de Máquina , Neoplasias , Óxidos , Titânio , Humanos , Titânio/química , Compostos de Cálcio/química , Neoplasias/diagnóstico , Neoplasias/patologia , Neoplasias/diagnóstico por imagem , Óxidos/química , Nanopartículas/química , Imagem Óptica , Corantes Fluorescentes/químicaRESUMO
Metal-metal bonding is crucial in chemistry for advancing our understanding of the fundamental aspects of chemical bonds. Metal-metal bonds based on alkaline-earth (Ae) elements, especially the heavier Ae elements (Ca, Sr, and Ba), are rarely reported due to their high electropositivity. Herein, we report two heteronuclear di-EMFs CaY@Cs(6)-C82 and CaY@C2v(5)-C80, which contain unprecedented single-electron Ca-Y metal-metal bonds. These compounds were characterized by single-crystal X-ray crystallography, electron paramagnetic resonance (EPR) spectroscopy, and DFT calculations. The crystallographic study of CaY@Cs(6)-C82 shows that Ca and Y are successfully encapsulated into the carbon cage with a Ca-Y distance of 3.691 Å. The CW-EPR study of both CaY@Cs(6)-C82 and CaY@C2v(5)-C80 exhibits a doublet, suggesting the presence of an unpaired electron located between Ca and Y. The combined experimental and theoretical results confirm the presence of a Ca-Y single-electron metal-metal bond with substantial covalent interaction, attributed to significant overlap between the 4s4p orbitals of Ca and the 5s5p4d orbitals of Y. Furthermore, pulse EPR spectroscopy was used to investigate the quantum coherence of the electron spin within this bond. The unpaired electron, characterized by its s orbital nature, is effectively protected by the carbon cage, resulting in efficient suppression of both spin-lattice relaxation and decoherence. CaY@Cs(6)-C82 behaves as an electron spin qubit, displaying a maximum decoherence time of 7.74 µs at 40 K. This study reveals an unprecedented Ae-rare-earth metal-metal bond stabilized by the fullerene cages and elucidates the molecular qubit properties stemming from their unique bonding character, highlighting their potential in quantum information processing applications.
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In this study, we aimed to investigate the molecular mechanism of Krüppel-like factor 7 (KLF7) in colorectal cancer (CRC) cell invasion and migration. The expression pattern of KLF7 in CRC tissues and the correlation between KLF7 expression and clinical symptoms of CRC were analyzed. CRC cell lines were transfected with si-KLF7, followed by qRT-PCR or western blot detection of KLF7, miR-139-5p, and tumor protein D52 (TPD52) expression, cell counting kit-8 (CCK-8) assay to detect cell viability, and transwell detection of invasion and migration. Chromatin immunoprecipitation (ChIP) analyzed the enrichment KLF7 in the miR-139-5p promoter. The dual-luciferase reporter assay verified the binding relationship between KLF7 and miR-139-5p, and between miR-139-5p and TPD52. In the subcutaneous tumorigenesis experiment, tumor growth was observed and ki67-positive expression was detected. KLF7 is abundantly expressed in CRC cells KLF7 silencing inhibits CRC cell viability, invasion, and migration. KLF7 represses miR-139-5p expression by binding to the miR-139-5p promoter. miR-139-5p targets TPD52 expression. miR-13-5p inhibition or TPD52 overexpression partially counteracted the effect of KLF7 silencing in CRC cells. KLF7 silencing suppresses tumor growth in vivo. In conclusion, KLF7 suppresses miR-139-5p expression by binding to the miR-139-5p promoter, thereby upregulating TPD52 expression and enhancing CRC cell invasion and migration.
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Movimento Celular , Neoplasias Colorretais , Fatores de Transcrição Kruppel-Like , MicroRNAs , Invasividade Neoplásica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Movimento Celular/genética , Camundongos , Animais , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Regulação Neoplásica da Expressão Gênica , Masculino , Proliferação de Células , Feminino , Linhagem Celular Tumoral , Camundongos NusRESUMO
Background: There is increasing evidence that macrophages are involved in the development of carotid atherosclerosis (CAS), but the specific mechanism is still unclear. We aimed to explore the key genes that play a regulatory role on macrophages in the progression of CAS. Methods: From 2021 August to 2023 August, GEO datasets GSE100927 and GSE43292 were downloaded and the key gene modules related to CAS were identified by weighted Gene co-expression network analysis (WGCNA). Kyoto Encyclopedia of Genes and Genes (KEGG) pathway analysis was performed on the genes of the key modules to identify common gene enrichment pathways. Differential expression analysis of pathway-related genes was performed by the "limma" package of R software. Case groups were categorized into high and low expression groups based on the expression levels of key genes, and ssGSEA immune infiltration analysis was performed. Results: The turquoise module of GSE100924 (threshold=12) and the brown module of GSE43292 (threshold=7) were obtained through WGCNA analysis. The analysis of KEGG showed that the differentially expressed genes in the turquoise and brown modules were co-enriched in the staphylococcus aureus infection signaling pathway. Differential expression analysis identified 18 common differentially expressed genes, all of which were highly expressed in the case group. C1QA is the gene of interest. According to ssGSEA analysis, the high expression group of C1QA showed a significant increase in the number of macrophages (GSE43292, P=0.0011; GSE100927, P=0.025). Conclusion: This study identified the key gene C1QA involved in regulating macrophage functional activity during the CAS process, providing new ideas for effective control of CAS.
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The design of optical systems not only considers the imaging performance but also the manufacturing difficulty and feasibility of the system. In practice, errors in the manufacturing process of glass materials and deviations in glass material parameters introduced in complex environments can both lead to degradation in the imaging quality of optical systems. Optical systems that are sensitive to glass material errors face increased manufacturing difficulty and reduced stability. This paper, based on geometrical optics theory, establishes an evaluation function for refractive index error sensitivity and analyzes its relationship with optical parameters and glass materials. It proposes a design method to reduce the refractive index sensitivity of optical systems. Through simulation verification and analysis using examples, the validity of the desensitization design method is confirmed.
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Heterocycles with saturated N atoms (HetSNs) are widely used electron donors in organic light-emitting diode (OLED) materials. Their relatively low bond dissociation energy (BDE) of exocyclic C-N bonds has been closely related to material intrinsic stability and even device lifetime. Thus, it is imperative to realize fast prediction and precise regulation of those C-N BDEs, which demands a deep understanding of the relationship between the molecular structure and BDE. Herein, via machine learning (ML), we rapidly and accurately predicted C-N BDEs in various HetSNs and found that five-membered HetSNs (5-HetSNs) have much higher BDEs than almost all 6-HetSNs, except emerging boron-N blocks. Thorough analysis disclosed that high aromaticity is the foremost factor accounting for the high BDE of 5-HetSNs, and introducing intramolecular hydrogen-bond or electron-withdrawing moieties could also increase BDE. Importantly, the ML models performed well in various realistic OLED materials, showing great potential in characterizing material intrinsic stability for high-throughput virtual-screening and material design efforts.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Organoides , PrognósticoRESUMO
Chirality dynamic tuning plays fundamental roles in chemistry, material science and biological system. Herein, a pair of azobenzene-bridged bis-tryptophan enantiomers (Azo-di-d/l-Trp) were designed and synthesized via simple reactions. With the fuel of glucono-δ-lactone (GdL), releasing protons during its hydrolysis, the alkaline solution of Azo-di-d/l-Trp gradually self-assembled into contrast chiral helical structures and displayed magnitude and mirror image of circular dichroism (CD) signals. While the chiral helices converted to CD silent nanoparticles when the azobenzene moiety isomerized from trans- to cis-form under UV irradiation. More importantly, this chiroptical switch, displaying reversible interconversion between chiral amplification and silent, can be smartly controlled via photoirradiation at various wavelengths.
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In this work, Y2O3: Tm3+, Eu3+ phosphors were made by homogeneous precipitation with urea as precipitator. The emission spectra varying with temperature of Y2O3: Tm3+, Eu3+ phosphors were measured and analyzed. Analysis show that the luminescence of Eu3+ represents a normal thermal quenching change, while that of Tm3+ exhibits slow thermal enhancement phenomenon. In the temperature range of 303-503 K, the luminescence of Tm3+ showed a trend of first strengthening and then weakening. The reason for this phenomenon of Tm3+ is that there is energy transfer from Eu3+ to Tm3+, and the energy transfer efficiency increases gradually with temperature. Meanwhile, the luminescence of Tm3+ also have thermal quenching effect. Under the combined influence of thermal quenching and energy transfer, the luminescence of Tm3+ first becomes stronger and then then becomes weaker. According to the calculation, the luminescence intensity ratio (LIR) of Tm3+ and Eu3+ conforms to the linear empirical formula with increasing temperature. The relative sensitivity of phosphors decreases with Eu3+ concentration increased, and the maximum Sr reaches 0.460% K-1 (1% Tm3+, 0.3% Eu3+, at 303 K). Moreover, the temperature cycle test present that the LIR of phosphors has good repeatability.
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Motivation: Family-based study design is one of the popular designs used in genetic research, and the whole-genome sequencing data obtained from family-based studies offer many unique features for risk prediction studies. They can not only provide a more comprehensive view of many complex diseases, but also utilize information in the design to further improve the prediction accuracy. While promising, existing analytical methods often ignore the information embedded in the study design and overlook the predictive effects of rare variants, leading to a prediction model with sub-optimal performance. Results: We proposed a Bayesian linear mixed model for the prediction analysis of sequencing data obtained from family-based studies. Our method can not only capture predictive effects from both common and rare variants, but also easily accommodate various disease model assumptions. It uses information embedded in the study design to form surrogates, where the predictive effects from unmeasured/unknown genetic and environmental risk factors can be modelled. Through extensive simulation studies and the analysis of sequencing data obtained from the Michigan State University Twin Registry study, we have demonstrated that the proposed method outperforms commonly adopted techniques. Availability: R package is available at https://github.com/yhai943/FBLMM.
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Despite decades of efforts, the actinide-carbon triple bond has remained an elusive target, defying synthesis in any isolable compound. Herein, we report the successful synthesis of uranium-carbon triple bonds in carbide-bridged bimetallic [U≡C-Ce] units encapsulated inside the fullerene cages of C72 and C78. The molecular structures of UCCe@C2n and the nature of the U≡C triple bond were characterized through X-ray crystallography and various spectroscopic analyses, revealing very short uranium-carbon bonds of 1.921(6) and 1.930(6) Å, with the metals existing in their highest oxidation states of +6 and +4 for uranium and cerium, respectively. Quantum-chemical studies further demonstrate that the C2n cages are crucial for stabilizing the [UVI≡C-CeIV] units through covalent and coordinative interactions. This work offers a new fundamental understanding of the elusive uranium-carbon triple bond and informs the design of complexes with similar bonding motifs, opening up new possibilities for creating distinctive molecular compounds and materials.
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Understanding metal-metal bonding involving f-block elements has been a challenging goal in chemistry. Here we report a series of mixed-valence di-metallofullerenes, ThDy@C2n (2n = 72, 76, 78, and 80) and ThY@C2n (2n = 72 and 78), which feature single electron actinide-lanthanide metal-metal bonds, characterized by structural, spectroscopic and computational methods. Crystallographic characterization unambiguously confirmed that Th and Y or Dy are encapsulated inside variably sized fullerene carbon cages. The ESR study of ThY@D3h(5)-C78 shows a doublet as expected for an unpaired electron interacting with Y, and a SQUID magnetometric study of ThDy@D3h(5)-C78 reveals a high-spin ground state for the whole molecule. Theoretical studies further confirm the presence of a single-electron bonding interaction between Y or Dy and Th, due to a significant overlap between hybrid spd orbitals of the two metals.
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Radiotherapy is an essential component of oncology treatment. It is imperative that clinicians and medical students have a fundamental understanding of radiotherapy. However, radiation oncology education is deficient worldwide. This study introduced an hour-long online Massive Open Online Course (MOOC) as a supplement to the basic curriculum for 8-year medical students at Peking Union Medical College and Tsinghua University in China. The students' personal opinions and comprehension of radiation oncology therapy were assessed through pre- and post-test questionnaires before and after the MOOC study. The results indicated that the percentage of students interested in radiotherapy increased, and their knowledge of radiotherapy significantly improved after the online MOOC study, suggesting that short-term MOOC study may stimulate students' interest in learning and improving their knowledge of radiation therapy. The study suggests that the combination of online and offline teaching may be a feasible way to develop radiation oncology education in the future.
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Educação a Distância , Radioterapia (Especialidade) , Estudantes de Medicina , Humanos , Radioterapia (Especialidade)/educação , População do Leste Asiático , Oncologia/educação , Currículo , PercepçãoRESUMO
PbS quantum dots (QDs) are attractive near-infrared (NIR) materials, but traditional synthetic methods require inert atmosphere and/or high temperature. Herein we develop a facile, room-temperature synthetic route for in situ halide passivated PbS QDs through controllable reactions between lead halide, N,N'-diphenyl thiourea, and oleyamine (OLA) in toluene. Contrast experiments and theoretical calculations reveal that the OLA plays a bifunctional role as a mild base to initiate the formation of PbS monomers and as a dynamic ligand to control the crystallization of PbS QDs and further ligand exchange. The oleic acid-capped PbS QDs exhibit high photoluminescence quantum yields up to 45%. The scaled-up synthesis on multigram scales shows great batch-to-batch consistency. We further demonstrate high-power NIR light-emitting diodes using the PbS QDs as color converters, delivering NIR optical power of 9.2 mW at 160 mA. This work provides a simple and versatile synthetic route for high-quality PbS QDs and boosts the applications of NIR materials.
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Actinide endohedral metallofullerenes (EMFs) are a fullerene family that possess unique actinide-carbon cage host-guest molecular and electronic structures. In this work, a novel actinide EMF, U@Cs(4)-C82, was successfully synthesized and characterized, and its chemical reactivity was investigated. Crystallographic analysis shows that U@Cs(4)-C82, a new isomer of U@C82, has a Cs(4)-C82 cage, which has never been discovered in the form of empty or endohedral fullerenes. Its unique chemical reactivities were further revealed through the Bingel-Hirsch reaction and carbene addition reaction studies. The Bingel-Hirsch reaction of U@Cs(4)-C82 shows exceptionally high selectivity and product yield, yielding only one major addition adduct. Moreover, the addition sites for both reactions are unexpectedly located on adjacent carbon atoms far away from the actinide metal, despite the nucleophilic (Bingel-Hirsch) and electrophilic (carbene addition) nature of either reactant. Density functional theory (DFT) calculations suggest that this chemical behavior, unprecedented for EMFs, is directed by the unusually strong interaction between U and the sumanene motif of the carbon cage in U@Cs(4)-C82, which makes the energy increase when it is disrupted. This work reveals remarkable chemical properties of actinide EMFs originating from their unique electronic structures and highlights the key role of actinide-cage interactions in the determination of their chemical behaviors.
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This study investigated the impact of mature compost input on compost quality, greenhouse gases (GHGs, i.e. methane and nitrous oxide) and ammonia emissions during chicken manure and rice husk chicken manure co-composting. The experiment used different volumes of mature compost: 10% (T1), 20% (T2), and 30% (T3) to replace rice husk chicken manure. Results showed that mature compost enhanced compost maturity by promoting the activities of Bacillus, Caldicoprobacter, Thermobifida, Pseudogracilibacillus, Brachybacterium, and Sinibacillus. Compared to CK, T1, T2, and T3 reduced NH3 emission by 32.07%, 33.64%, and 56.12%, and mitigated 14.97%, 16.57%, and 26.18% of total nitrogen loss, respectively. Additionally, T2 and T3 reduced CH4 emission by 40.98% and 62.24%, respectively. The N2O emissions were positive correlation with Lactobacillus, Pseudogracilibacillus and ammonium nitrogen (p < 0.05), while T2 reducing total greenhouse effects. Therefore, replacing rice husk chicken manure with 20% mature compost is an efficient and promising approach for composting.