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Mimicking hierarchical assembly in nature to exploit atomically precise artificial systems with complex structures and versatile functions remains a long-standing challenge. Herein, we report two single-crystal supramolecular organic frameworks (MSOF-4 and MSOF-5) based on custom-designed atomically precise gold nanoclusters Au11(4-Mpy)3(PPh3)7, showing distinct and intriguing host-guest adaptation behaviors toward 1-/2-bromopropane (BPR) isomers. MSOF-4 exhibits sev topology and cylindrical channels with 4-mercaptopyridine (4-Mpy) ligands matching well with guest 1-BPR. Due to the confinement effect, solid MSOF-4 undergoes significant structural change upon selective adsorption of 1-BPR vapor over 2-BPR, resulting in strong near-infrared fluorescence. Single-crystal X-ray diffraction reveals that Au11(4-Mpy)3(PPh3)7 in MSOF-4 transforms into Au11Br3(PPh3)7 upon ligand exchange with 1-BPR, resulting in 1-BPR@MSOF-6 single crystals with a rarely reported helical assembly structure. Significantly, the double-helical structure of MSOF-6 facilitates efficient catalysis of the electron transfer (ET) reaction, resulting in a nearly 6 times increase of catalytic rates compared with MSOF-4. In sharp contrast, solid MSOF-5 possesses chb topology and cage-type channels with narrow windows, showing excellent selective physical adsorption toward 1-BPR vapor but a nonfluorescent feature upon guest adsorption. Our results demonstrate a powerful strategy for developing advanced assemblies with high-order complexity and engineering their functions in atomic precision.
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As a free radical and endogenous effector molecule, mammalian endogenous nitric oxide (NO) is mainly derived from nitric oxide synthase (NOS) via L-arginine. NO participates in normal physiological reactions and provides immune responses to prevent the invasion of foreign bacteria. However, NO also has complex and contradictory biological effects. Abnormal NO signaling is involved in the progression of many diseases, such as cancer. In the past decades, cancer research has been closely linked with NOS/ NO, and many tumors with poor prognosis are associated with high expression of NOS. In this review, we give a overview of the biological effects of NOS/ NO. Then we focus on the oncogenic role of iNOS/ NO in HPV, HBV, EBV and H. pylori related tumors. In fact, there is growing evidence that iNOS could be used as a potential therapeutic target in cancer therapy. We emphasize that the pro-tumor effect of NOS/ NO is greater than the anti-tumor effect.
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Cancer continues to pose a significant threat to global health, with its status as a leading cause of death remaining unchallenged. Within the realm of cancer research, the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) stands out as a critical player, having been identified in the 1990s as the tenth member of the TNF family. This review examines the pivotal role of TRAIL in cancer biology, focusing on its ability to induce apoptosis in malignant cells through both endogenous and exogenous pathways. We provide an in-depth analysis of TRAIL's intracellular signaling and intercellular communication, underscoring its potential as a selective anticancer agent. Additionally, the review explores TRAIL's capacity to reshape the tumor microenvironment, thereby influencing cancer progression and response to therapy. With an eye towards future developments, we discuss the prospects of harnessing TRAIL's capabilities for the creation of tailored, precision-based cancer treatments, aiming to enhance efficacy and improve patient survival rates.
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Ferroptosis is a novel and iron-dependent form of programmed cell death, which has been implicated in the pathogenesis of various human cancers. EBV is a well-recognized oncogenic virus that controls multiple signaling pathways within the host cell, including ferroptosis signaling. Recent studies show that inducing ferroptosis could be an efficient therapeutic strategy for EBV-associated tumors. This review will firstly describe the mechanism of ferroptosis, then summarize EBV infection and EBV-associated tumors, as well as the crosstalk between EBV infection and the ferroptosis signaling pathway, and finally discuss the role and potential application of ferroptosis-related reagents in EBV-associated tumors.
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AIM: To investigate the DNA damage response (DDR) in a cyclophosphamide (CTX)-induced mouse model of premature ovarian failure (POF). METHODS: The POF model was established by injecting mice with CTX. The body, ovarian weights, the estrus cycle, and pathological changes of the ovaries were recorded. The serum levels of 17 ß-estradiol (E2) and follicle-stimulating hormone (FSH) were measured. The expression of Ki67, ß-galactosidase (ß-gal), p21, p53, γH2AX, and pATM in ovarian tissues was detected by immunohistochemistry. The expression of ß-gal, γH2AX, and pATM was analyzed by immunofluorescence staining of primary cultured granulosa cells (GCs). RESULTS: The body and ovarian weights decreased, the estrus cycles were erratic, and the FSH level increased, whereas the E2 level decreased in POF mice compared to controls. The pathological consequences of POF revealed an increase in atretic follicles, corpus luteum, and primordial follicles and a decrease in the number of primary, secondary, and tertiary follicles. Ki67 expression was reduced, ß-gal, p21, p53, γH2AX, and pATM expression were elevated in the ovaries of POF mice. The expression of ß-gal, γH2AX, and pATM increased in GCs with the concentration in a time-dependent manner. CONCLUSION: In total, CTX induced POF in mice, which was mediated by the DDR pathway of ATM-P53-P21.
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KNOXs, a type of homeobox genes that encode atypical homeobox proteins, play an essential role in the regulation of growth and development, hormonal response, and abiotic stress in plants. However, the KNOX gene family has not been explored in sweet potato. In this study, through sequence alignment, genomic structure analysis, and phylogenetic characterization, 17, 12 and 11 KNOXs in sweet potato (I. batatas, 2n = 6x = 90) and its two diploid relatives I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30) were identified. The protein physicochemical properties, chromosome localization, phylogenetic relationships, gene structure, protein interaction network, cis-elements of promoters, tissue-specific expression and expression patterns under hormone treatment and abiotic stresses of these 40 KNOX genes were systematically studied. IbKNOX4, -5, and - 6 were highly expressed in the leaves of the high-yield varieties Longshu9 and Xushu18. IbKNOX3 and IbKNOX8 in Class I were upregulated in initial storage roots compared to fibrous roots. IbKNOXs in Class M were specifically expressed in the stem tip and hardly expressed in other tissues. Moreover, IbKNOX2 and - 6, and their homologous genes were induced by PEG/mannitol and NaCl treatments. The results showed that KNOXs were involved in regulating growth and development, hormone crosstalk and abiotic stress responses between sweet potato and its two diploid relatives. This study provides a comparison of these KNOX genes in sweet potato and its two diploid relatives and a theoretical basis for functional studies.
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Diploide , Regulação da Expressão Gênica de Plantas , Ipomoea batatas , Família Multigênica , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Ipomoea batatas/genética , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Genoma de Planta , Perfilação da Expressão Gênica , Regiões Promotoras GenéticasRESUMO
The dynamic optical response properties and the distinct features of nanomaterials make photoswitchable fluorescent nanoparticles (PF NPs) attractive candidates for advanced optical applications. Over the past few decades, the design of PF NPs by coupling photochromic and fluorescent motifs at the nanoscale has been actively pursued, and substantial efforts have been made to exploit their potential applications. In this perspective, we critically summarize various design principles for fabricating these PF NPs. Then, we discuss their distinct optical properties from different aspects by highlighting the capability of NPs in fabricating new, robust photoswitch systems. Afterwards, we introduce the pivotal role of PF NPs in advanced optical applications, including sensing, anti-counterfeiting and imaging. Finally, current challenges and future development of PF NPs are briefly discussed.
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The distinct features of nanoparticles have provided a vast opportunity of developing new diagnosis and therapy strategies for miscellaneous diseases. Although a few nanomedicines are available in the market or in the translation stage, many important issues are still unsolved. When entering the body, nanomaterials will be quickly coated by proteins from their surroundings, forming a corona on their surface, the so-called protein corona. Studies have shown that the protein corona has many important biological implications, particularly at the in vivo level. For example, they can promote the immune system to rapidly clear these outer materials and prevent nanoparticles from playing their designed role in therapy. In this Perspective, the available techniques for characterizing protein-nanoparticle interactions are critically summarized. Effects of nanoparticle properties and environmental factors on protein corona formation, which can further regulate the in vivo fate of nanoparticles, are highlighted and discussed. Moreover, recent progress on the biomedical application of protein corona-engineered nanoparticles is introduced, and future directions for this important yet challenging research area are also briefly discussed.
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Nanopartículas , Coroa de Proteína , Coroa de Proteína/metabolismo , Nanopartículas/metabolismo , Proteínas/metabolismo , Nanomedicina , Ligação ProteicaRESUMO
OBJECTIVE: To explore the risk factors affecting the survival and efficacy of patients with acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) transformed from myelodysplastic syndrome (MDS). METHODS: The clinical data of 60 patients with AML-MRC transformed from MDS who hospitalized in The Third Affiliated Hospital of Soochow University from January 2010 to December 2021 were retrospectively analyzed. The demographic data and laboratory parameters, cytogenetic karyotypes, target genes of AML detected by next generation sequence, risk stratification, treatment regimen, therapeutic efficacy and survival outcome were documented. Rank sum test and Chi-square test or Fisher exact test were used to compare the survival and efficacy. The effects of clinical parameters, risk stratification and treatment regimens on the survival and efficacy of the AML-MRC patients were analyzed by univariate and multivariate analysis. RESULTS: The median overall survival (OS) of the AML-MRC patients was 4.5 months, the 1-year OS rate was 28.3%, and the complete remission (CR) rate after treatment was 33.3%. The univariate analysis showed that age≥60 years, leukocytosis, severe thrombocytopenia, poor-risk group and only accepted hypomethylating agents(HMAs) or supportive therapy were the risk factors affecting OS. COX multivariate analysis showed that thrombocytopenia ( HR=4.46), HMAs therapy (compared to transplantation, HR=10.47), supportive therapy (compared to transplantation, HR=25.80) and poor-risk group (compared to medium-risk group, HR=13.86) were independent hazard factors for median OS of patients with AML-MRC. The univariate analysis showed that the risk factors affecting 1-year OS in patients with AML-MRC were age≥60 years, thrombocytopenia, time of transformation from MDS to AML (TTA)≥3 months, fibrinogen-albumin ratio index (FARI)≥0.07, CONUT score≥5, poor-risk group and supportive therapy. Binary logistic regression analysis showed that the independent risk factors for 1-year OS in AML-MRC patients were age≥60 years ( HR=11.23), thrombocytopenia ( HR=8.71), FARI≥0.07 ( HR=5.19) and poor-risk group ( HR=14.00). The risk factors affecting CR of AML-MRC patients in univariate analysis were age≥60 years, thrombocytopenia, FARI≥0.1, CONUT score≥5, poor-risk group and supportive therapy, while binary logistic regression analysis showed that age≥60 years( HR=7.35), CONUT score≥5 ( HR=9.60), thrombocytopenia ( HR=12.05) and poor-risk group ( HR=32.5) were independent risk factors affecting CR of the patients. CONCLUSION: The OS of AML-MRC patients is poor, old age(≥60 years old), supportive therapy, HMA therapy, poor-risk, thrombocytopenia, FARI≥0.07 and CONUT score≥5 may be associated with poor prognosis.
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Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Síndromes Mielodisplásicas/complicações , Prognóstico , Taxa de Sobrevida , Fatores de Risco , Pessoa de Meia-Idade , Progressão da Doença , Trombocitopenia/etiologia , Feminino , Indução de Remissão , MasculinoRESUMO
Metabolic reprogramming induced by Epstein-Barr virus (EBV) often mirrors metabolic changes observed in cancer cells. Accumulating evidence suggests that lytic reactivation is crucial in EBV-associated oncogenesis. The aim of this study was to explore the role of metabolite changes in EBV-associated malignancies and viral life cycle control. We first revealed that EBV (LMP1) accelerates the secretion of the oncometabolite D-2HG, and serum D-2HG level is a potential diagnostic biomarker for NPC. EBV (LMP1)-driven metabolite changes disrupts the homeostasis of global DNA methylation and demethylation, which have a significantly inhibitory effect on active DNA demethylation and 5hmC content. We found that loss of 5hmC indicates a poor prognosis for NPC patients, and that 5hmC modification is a restriction factor of EBV reactivation. We confirmed a novel EBV reactivation inhibitor, α-KG, which inhibits the expression of EBV lytic genes with CpG-containing ZREs and the latent-lytic switch by enhancing 5hmC modification. Our results demonstrate a novel mechanism of which metabolite abnormality driven by EBV controls the viral lytic reactivation through epigenetic modification. This study presents a potential strategy for blocking EBV reactivation, and provides potential targets for the diagnosis and therapy of NPC.
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Metilação de DNA , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Ativação Viral , Humanos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Carcinoma Nasofaríngeo/virologia , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/virologia , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Infecções por Vírus Epstein-Barr/virologia , Infecções por Vírus Epstein-Barr/complicações , Proteínas da Matriz Viral/metabolismo , Proteínas da Matriz Viral/genética , Epigênese Genética , Progressão da DoençaRESUMO
BACKGROUND: Generally, cardiopulmonary resuscitation (CPR) skills decline substantially over time. By combining web-based self-regulated learning with hands-on practice, blended training can be a time- and resource-efficient approach enabling individuals to acquire or refresh CPR skills at their convenience. However, few studies have evaluated the effectiveness of blended CPR refresher training compared with that of the traditional method. OBJECTIVE: This study investigated and compared the effectiveness of traditional and blended CPR training through 6-month and 12-month refresher sessions with CPR ability indicators. METHODS: This study recruited participants aged ≥18 years from the Automated External Defibrillator Donation Project. The participants were divided into 4 groups based on the format of the CPR training and refresher training received: (1) initial traditional training (a 30-minute instructor-led, hands-on session) and 6-month traditional refresher training (Traditional6 group), (2) initial traditional training and 6-month blended refresher training (an 18-minute e-learning module; Mixed6 group), (3) initial traditional training and 12-month blended refresher training (Mixed12 group), and (4) initial blended training and 6-month blended refresher training (Blended6 group). CPR knowledge and performance were evaluated immediately after initial training. For each group, following initial training but before refresher training, a learning effectiveness assessment was conducted at 12 and 24 months. CPR knowledge was assessed using a written test with 15 multiple-choice questions, and CPR performance was assessed through an examiner-rated skill test and objectively through manikin feedback. A generalized estimating equation model was used to analyze changes in CPR ability indicators. RESULTS: This study recruited 1163 participants (mean age 41.82, SD 11.6 years; n=725, 62.3% female), with 332 (28.5%), 270 (23.2%), 258 (22.2%), and 303 (26.1%) participants in the Mixed6, Traditional6, Mixed12, and Blended6 groups, respectively. No significant between-group difference was observed in knowledge acquisition after initial training (P=.23). All groups met the criteria for high-quality CPR skills (ie, average compression depth: 5-6 cm; average compression rate: 100-120 beats/min; chest recoil rate: >80%); however, a higher proportion (98/303, 32.3%) of participants receiving blended training initially demonstrated high-quality CPR skills. At 12 and 24 months, CPR skills had declined in all the groups, but the decline was significantly higher in the Mixed12 group, whereas the differences were not significant between the other groups. This finding indicates that frequent retraining can maintain high-quality CPR skills and that blended refresher training is as effective as traditional refresher training. CONCLUSIONS: Our findings indicate that 6-month refresher training sessions for CPR are more effective for maintaining high-quality CPR skills, and that as refreshers, self-learning e-modules are as effective as instructor-led sessions. Although the blended learning approach is cost and resource effective, factors such as participant demographics, training environment, and level of engagement must be considered to maximize the potential of this approach. TRIAL REGISTRATION: IGOGO NCT05659108; https://www.cgmh-igogo.tw.
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Reanimação Cardiopulmonar , Humanos , Reanimação Cardiopulmonar/educação , Feminino , Estudos Prospectivos , Masculino , Pessoa de Meia-Idade , Adulto , Competência Clínica , Avaliação EducacionalRESUMO
An improved innate immunity will respond quickly to pathogens and initiate efficient adaptive immune responses. However, up to now, there have been limited clinical ways for effective and rapid consolidation of innate immunity. Here, we report that cutaneous irradiation with blue light of 450 nm rapidly stimulates the innate immunity through cell endogenous reactive oxygen species (ROS) regulation in a noninvasive way. The iron porphyrin-containing proteins, mitochondrial cytochrome c (Cyt-c), and cytochrome p450 (CYP450) can be mobilized by blue light, which boosts electron transport and ROS production in epidermal and dermal tissues. As a messenger of innate immune activation, the increased level of ROS activates the NF-κB signaling pathway and promotes the secretion of immunomodulatory cytokines in skin. Initiated from skin, a regulatory network composed of cytokines and immune cells is established through the circulation system for innate immune activation. The innate immunity activated by whole-body blue light irradiation inhibits tumor growth and metastasis by increasing the infiltration of antitumor neutrophils and tumor-associated macrophages. Our results elucidate the remote immune modulation mechanism of blue light and provide a clinically applicable way for innate immunity activation.
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Chronic wounds of significant severity and acute injuries are highly vulnerable to fungal infections, drastically impeding the expected wound healing trajectory. The clinical use of antifungal therapeutic drug is hampered by poor solubility, high toxicity and adverse reactions, thereby necessitating the urgent development of novel antifungal therapy strategy. Herein, this study proposes a new strategy to enhance the bioactivity of small-molecule antifungal drugs based on multifunctional metal nanozyme engineering, using amphotericin B (AmB) as an example. AmB-decorated gold nanoparticles (AmB@AuNPs) are synthesized by a facile one-pot reaction strategy, and the AmB@AuNPs exhibit superior peroxidase (POD)-like enzyme activity, with maximal reaction rates (Vmax) 3.4 times higher than that of AuNPs for the catalytic reaction of H2O2. Importantly, the enzyme-like activity of AuNPs significantly enhanced the antifungal properties of AmB, and the minimum inhibitory concentrations of AmB@AuNPs against Candida albicans (C. albicans) and Saccharomyces cerevisiae (S. cerevisiae) W303 are reduced by 1.6-fold and 50-fold, respectively, as compared with AmB alone. Concurrent in vivo studies conducted on fungal-infected wounds in mice underscored the fundamentally superior antifungal ability and biosafety of AmB@AuNPs. The proposed strategy of engineering antifungal drugs with nanozymes has great potential for enhanced therapy of fungal infections and related diseases.
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Anfotericina B , Antifúngicos , Candida albicans , Ouro , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Ouro/química , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/uso terapêutico , Anfotericina B/farmacologia , Anfotericina B/química , Anfotericina B/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Candida albicans/efeitos dos fármacos , Animais , Saccharomyces cerevisiae/efeitos dos fármacos , CamundongosRESUMO
Presenilin-2 (PSEN2) mutation is one of the pathogenic factors of autosomal dominant early-onset Alzheimer's disease (EOAD). We generated a human induced pluripotent stem cell (iPSC) line from fibroblasts of an EOAD patient carrying PSEN2 mutation (c.716 T > C) utilizing Sendai reprogramming kit. The resulting iPSC line carried patient-specific point mutation, exhibited typical iPSC morphology, retained a normal karyotype, expressed pluripotency markers, and could form embryoid bodies. Established iPSC line serve as valuable resource for EOAD disease pathogenesis modelling and drug screening.
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Fibroblastos , Células-Tronco Pluripotentes Induzidas , Presenilina-2 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Fibroblastos/metabolismo , Presenilina-2/genética , Presenilina-2/metabolismo , Mutação , Pele/patologia , Pele/citologia , Linhagem Celular , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Diferenciação Celular , Reprogramação Celular , MasculinoRESUMO
The detection of physiological phosphates (PPs) is of great importance due to their essential roles in numerous biological processes, but the efficient detection of different PPs simultaneously remains challenging. In this work, we propose a fluorescence sensor array for detecting PPs based on metal-ion-regulated gold nanoclusters (AuNCs) via an indicator-displacement assay. Zn2+ and Eu3+ are selected to assemble with two different AuNCs, resulting in quenching or enhancing their fluorescence. Based on the competitive interaction of metal ions with AuNCs and PPs, the fluorescence of AuNCs will be recovered owing to the disassembly of AuNC-metal ion ensembles. Depending on different PPs' distinct fluorescence responses, a four-channel sensor array was established. The array not only exhibits good discrimination capability for eight kinds of PPs (i.e., ATP, ADP, AMP, GTP, CTP, UTP, PPi, and Pi) via linear discriminant analysis but also enables quantitative detection of single phosphate (e.g., ATP) in the presence of interfering PPs mixtures. Moreover, potential application of the present sensor array for the discrimination of different PPs in real samples (e.g., cell lysates and serum) was successfully demonstrated with a good performance. This work illustrates the great potential of a metal ion-regulated sensor array as a new and efficient sensing platform for differential sensing of phosphates as well as other disease-related biomolecules.
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Ouro , Nanopartículas Metálicas , Corantes Fluorescentes , Espectrometria de Fluorescência/métodos , Fosfatos , Trifosfato de AdenosinaRESUMO
Colorectal cancer (CRC) is a type of gastrointestinal cancer with high morbidity and mortality rates, and is often accompanied by distant metastases. Metastasis is a major cause of shortened survival time and poor treatment outcomes for patients with CRC. However, the molecular mechanisms underlying the metastasis of CRC remain unclear. Exosomes are a class of small extracellular vesicles that originate from almost all human cells and can transmit biological information (e.g., nucleic acids, lipids, proteins, and metabolites) from secretory cells to target recipient cells. Recent studies have revealed that non-coding RNAs (ncRNAs) can be released by exosomes into the tumour microenvironment or specific tissues, and play a pivotal role in tumorigenesis by regulating a series of key molecules or signalling pathways, particularly those involved in tumour metastasis. Exosomal ncRNAs have potential as novel therapeutic targets for CRC metastasis, and can also be used as liquid biopsy biomarkers because of their specificity and sensitivity. Therefore, further investigations into the biological function and clinical value of exosomal ncRNAs will be of great value for the prevention, early diagnosis, and treatment of CRC metastasis.
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Neoplasias Colorretais , Exossomos , Vesículas Extracelulares , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/diagnóstico , RNA não Traduzido/genética , Exossomos/metabolismo , Vesículas Extracelulares/patologia , Transdução de Sinais , Microambiente TumoralRESUMO
The current challenge of wearable/implantable personal dosimeters for medical diagnosis and radiotherapy applications is lack of suitable detector materials possessing both excellent detection performance and biocompatibility. Here, we report a solution-grown biocompatible organic single crystalline semiconductor (OSCS), 4-Hydroxyphenylacetic acid (4HPA), achieving real-time spectral detection of charged particles with single-particle sensitivity. Along in-plane direction, two-dimensional anisotropic 4HPA exhibits a large electron drift velocity of 5 × 105 cm s-1 at "radiation-mode" while maintaining a high resistivity of (1.28 ± 0.003) × 1012 Ω·cm at "dark-mode" due to influence of dense π-π overlaps and high-energy L1 level. Therefore, 4HPA detectors exhibit the record spectra detection of charged particles among their organic counterparts, with energy resolution of 36%, (µt)e of (4.91 ± 0.07) × 10-5 cm2 V-1, and detection time down to 3 ms. These detectors also show high X-ray detection sensitivity of 16,612 µC Gyabs-1 cm-3, detection of limit of 20 nGyair s-1, and long-term stability after 690 Gyair irradiation.