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Heat stress limits plant growth, development, and crop yield, but how plant cells precisely sense and transduce heat stress signals remains elusive. Here, we identified a conserved heat stress response mechanism to elucidate how heat stress signal is transmitted from the cytoplasm into the nucleus for epigenetic modifiers. We demonstrate that HISTONE DEACETYLASE 9 (HDA9) transduces heat signals from the cytoplasm to the nucleus to play a positive regulatory role in heat responses in Arabidopsis. Heat specifically induces HDA9 accumulation in the nucleus. Under heat stress, the phosphatase PP2AB'ß directly interacts with and dephosphorylates HDA9 to protect HDA9 from 26S proteasome-mediated degradation, leading to the translocation of nonphosphorylated HDA9 to the nucleus. This heat-induced enrichment of HDA9 in the nucleus depends on the nucleoporin HOS1. In the nucleus, HDA9 binds and deacetylates the target genes related to signaling transduction and plant development to repress gene expression in a transcription factor YIN YANG 1-dependent and -independent manner, resulting in rebalance of plant development and heat response. Therefore, we uncover an HDA9-mediated positive regulatory module in the heat shock signal transduction pathway. More important, this cytoplasm-to-nucleus translocation of HDA9 in response to heat stress is conserved in wheat and rice, which confers the mechanism significant implication potential for crop breeding to cope with global climate warming.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Células Vegetais/metabolismo , Melhoramento Vegetal , Arabidopsis/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismoRESUMO
Realizing high-performance thick electrodes is considered as a practical strategy to promote the energy density of lithium-ion batteries. However, establishing effective transport pathways for both lithium-ions and electrons in a thick electrode is very challenging. This study develops a hierarchical conductive network structure for constructing high-performance NMC811 (LiNi0.8Mn0.1Co0.1O2) cathode toward stable cycling at high areal mass loadings. The hierarchical conductive networks are composed of a Li+/e- mixed conducting interface (lithium polyacrylate/hydroxyl-functionalized multiwalled carbon nanotubes) on NMC811 particles, and a segregated network of single-walled carbon nanotubes in the electrode, without any additional binders or carbon black. Such strategy endows the NMC811 cathode (up to 250 µm and 50 mg cm-2) with low porosity/tortuosity, ultrahigh Li+/e- conductivities and excellent mechanical property at low carbon nanotube content (1.8 wt%). It significantly improves the electrochemical reaction homogeneity along the electrode depth, meanwhile effectively inhibits the side reactions at the electrode/electrolyte interface and cracks in the NMC particles during cycling. This work emphasizes the crucial role of the electronic/ionic cooperative transportation in the performance deterioration of thick cathodes, and provide guidance for architecture optimization and performance improvement of thick electrodes toward practical applications, not just for the NMC811 cathode.
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BACKGROUND: Surgery combined with radiotherapy substantially escalates the likelihood of encountering complications in early-stage cervical squamous cell carcinoma(ESCSCC). We aimed to investigate the feasibility of Deep-learning-based radiomics of intratumoral and peritumoral MRI images to predict the pathological features of adjuvant radiotherapy in ESCSCC and minimize the occurrence of adverse events associated with the treatment. METHODS: A dataset comprising MR images was obtained from 289 patients who underwent radical hysterectomy and pelvic lymph node dissection between January 2019 and April 2022. The dataset was randomly divided into two cohorts in a 4:1 ratio.The postoperative radiotherapy options were evaluated according to the Peter/Sedlis standard. We extracted clinical features, as well as intratumoral and peritumoral radiomic features, using the least absolute shrinkage and selection operator (LASSO) regression. We constructed the Clinical Signature (Clinic_Sig), Radiomics Signature (Rad_Sig) and the Deep Transformer Learning Signature (DTL_Sig). Additionally, we fused the Rad_Sig with the DTL_Sig to create the Deep Learning Radiomic Signature (DLR_Sig). We evaluated the prediction performance of the models using the Area Under the Curve (AUC), calibration curve, and Decision Curve Analysis (DCA). RESULTS: The DLR_Sig showed a high level of accuracy and predictive capability, as demonstrated by the area under the curve (AUC) of 0.98(95% CI: 0.97-0.99) for the training cohort and 0.79(95% CI: 0.67-0.90) for the test cohort. In addition, the Hosmer-Lemeshow test, which provided p-values of 0.87 for the training cohort and 0.15 for the test cohort, respectively, indicated a good fit. DeLong test showed that the predictive effectiveness of DLR_Sig was significantly better than that of the Clinic_Sig(P < 0.05 both the training and test cohorts). The calibration plot of DLR_Sig indicated excellent consistency between the actual and predicted probabilities, while the DCA curve demonstrating greater clinical utility for predicting the pathological features for adjuvant radiotherapy. CONCLUSION: DLR_Sig based on intratumoral and peritumoral MRI images has the potential to preoperatively predict the pathological features of adjuvant radiotherapy in early-stage cervical squamous cell carcinoma (ESCSCC).
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Carcinoma de Células Escamosas , Aprendizado Profundo , Neoplasias do Colo do Útero , Feminino , Humanos , Radioterapia Adjuvante , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/radioterapia , Radiômica , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Imageamento por Ressonância Magnética , Estudos RetrospectivosRESUMO
BACKGROUND: Exposure to different concentration levels of fatty acids (FAs) may have an impact on depression. However, previous studies using individual FAs may not reflect the performance of mixtures of various FAs, and the associations of FA patterns with depression remain unclear. METHODS: We conducted the cross-sectional analysis in 792 adults aged 18 and older with available serum FAs and depression screening data in the National Health and Nutrition Examination Survey (NHANES) 2011-2012. The serum concentrations of thirty FAs were measured using gas chromatography-mass spectrometry and their percentage compositions were subsequently calculated. Depression was defined as the Patient Health Questionnaire-9 score ≥ 10. We employed principal component analysis to derive serum FA patterns. We examined the association between these patterns and depression in the overall population and various subgroups through survey-weighted logistic regression. RESULTS: Four distinct patterns of serum FAs were identified: 'high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); low docosatetraenoic acid (DTA) and docosapentaenoic acid (DPA) n-6', 'high long-chain saturated FA and long chain FA', 'low median-chain saturated FA and myristoleic acid' and 'low capric acid and lauric acid; high gamma-linolenic acid (GLA) and stearidonic acid (SDA)' pattern. Individuals in the high tertile of 'high EPA and DHA; low DTA and DPA n-6' pattern score had 0.46 (95% CI: 0.22, 0.93) lower odds of developing depression compared to individuals in the lowest tertile after adjusting for confounders such as age, sex, physical activity and total energy intake, etc. The odds ratio (OR) of depression was increased in the population with the highest tertile of 'low capric acid and lauric acid; high GLA and SDA' pattern (OR: 2.45, 95% CI: 1.24, 4.83). In subgroup analyses, we observed that the association between 'high EPA and DHA; low DTA and DPA n-6' and depression persisted among specific demographic and lifestyle subgroups, including females, non-Mexican Americans, non-obese, those aged over 60 years, smokers and drinkers. Similarly, 'low capric acid and lauric acid; high GLA and SDA' showed stable associations in female, non-Mexican Americans and smokers. CONCLUSIONS: Serum FA patterns are associated with depression, and their relationships vary across sex, race, BMI, age, smoking and drinking subgroups, highlighting the importance of considering specific FA patterns within these demographic and lifestyle categories. Utilization of combined FA administration may serve as a mitigation measure against depression in these specific populations.
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Depressão , Ácidos Graxos , Inquéritos Nutricionais , Humanos , Feminino , Masculino , Depressão/sangue , Depressão/epidemiologia , Adulto , Pessoa de Meia-Idade , Ácidos Graxos/sangue , Estudos Transversais , Estados Unidos/epidemiologia , Ácidos Decanoicos/sangue , Ácido Eicosapentaenoico/sangue , Idoso , Ácidos Graxos Insaturados/sangue , Adulto Jovem , Adolescente , Análise de Componente PrincipalRESUMO
BACKGROUND: The likelihood of advanced or synchronous neoplasms is significantly higher in fecal immunochemical test (FIT)-positive individuals than in the general population. The magnitude of the colonoscopy-related complication rate in FIT-positive individuals remains unknown. This study aimed to elucidate the colonoscopy-related complication rate after a positive FIT result and compare it with the rate when colonoscopy was performed for other purposes. METHODS: Information regarding colonoscopy-related severe complications after a positive FIT result (FIT-colonoscopy) and ordinary colonoscopy during 2010-2014 was collected from the Taiwanese Colorectal Cancer Screening Program Database and National Health Insurance Research Database. Severe complications included significant bleeding, perforation, and cardiopulmonary events ≤â14 days after colonoscopy. The number of events per 1000 procedures was used to quantify complication rates. Multivariate analysis was conducted to assess the association of various factors with severe complications associated with FIT-colonoscopy compared with ordinary colonoscopy. RESULTS: 319â 114 FIT-colonoscopies (214â 955 patients) were identified, 51â 242 (16.1â%) of which included biopsy and 94â 172 (29.5â%) included polypectomy. Overall, 2125 significant bleedings (6.7â) and 277 perforations (0.9â) occurred ≤â14 days after FIT-colonoscopy. Polypectomy, antiplatelet use, and anticoagulant use were associated with higher risk of complications (adjusted odds ratio [aOR] 4.41, 95â% confidence interval [CI] 4.05-4.81); aOR 1.35, 95â%CI 1.12-1.53; aOR 1.88, 95â%CI 0.61-5.84, respectively). Compared with ordinary colonoscopy, FIT-colonoscopy involved significantly higher risk of significant bleeding (aOR 3.10, 95â%CI 2.90-3.32). CONCLUSIONS: FIT-colonoscopy was associated with a more than two-fold risk of significant bleeding, especially when polypectomy was performed.
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Neoplasias Colorretais , Detecção Precoce de Câncer , Biópsia , Colonoscopia/efeitos adversos , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer/efeitos adversos , Detecção Precoce de Câncer/métodos , Fezes , Humanos , Programas de Rastreamento/métodos , Sangue OcultoRESUMO
BACKGROUND: PER2 gene methylation is closely related to the occurrence and progress of some cancers, but there is no method to quantitatively detect PER2 methylation in conventional laboratories. So, we established a TaqMan real-time fluorescence quantitative methylation specific PCR (TaqMan real-time FQ-MSP) assay and use it for quantitative detection of PER2 methylation in leukemia patients. METHODS: According to the PER2 sequence searched by GenBank, a CpG sequence enrichment region of the PER2 gene promoter was selected, and the methylated and unmethylated target sequences were designed according to the law of bisulfite conversion of DNA to construct PER2 methylation positive and negative reference materials. Specific primers and probe were designed. The reference materials were continuously diluted into gradient samples by tenfold ratio to evaluate the analytical sensitivity, specificity, accuracy and reproducibility of the method, and the analytical sensitivity of TaqMan real-time FQ-MSP assay was compared with that of the conventional MSP assay. At the same time, the new-established TaqMan real-time FQ-MSP assay and the conventional MSP assay were used to detect the PER2 methylation level of 81 patients with leukemia, and the samples with inconsistent detection results of the two assays were sent to pyromethylation sequencing to evaluate the clinical detection performance. RESULTS: The minimum detection limit of TaqMan real-time FQ-MSP assay for detecting PER2 methylation level established in this study was 6 copies/uL, and the coefficient of variation(CV) of intra-assay and inter-assay was less than 3%. Compared with the conventional MSP assay, it has higher analytical sensitivity. For the samples with inconsistent detection results, the results of pyrosequencing and TaqMan real-time FQ-MSP assay are consistent. CONCLUSION: TaqMan real-time FQ-MSP assay of PER2 methylation established in this study has high detection performance and can be used for the detection of clinical samples.
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Metilação de DNA , Proteínas Circadianas Period , Reação em Cadeia da Polimerase em Tempo Real , Metilação de DNA/genética , Humanos , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Circadian rhythm is a periodic change of organism according to the law of external environment, which is manifested in metabolism, cell proliferation, physiology and behavior. In recent years, the role of circadian genes in the occurrence and progression of hematological malignancies have been continuously demonstrated. PER2 is the core component of the circadian rhythm playing an important role in regulating the circadian rhythm of the biological clock. This review summarizes the research progress of PER2 in hematological malignancies, especially leukemia, in order to better understand its role in hematological malignancies, and provide new ideas for clinical diagnosis and treatment.
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Proliferação de Células , Ritmo Circadiano , Neoplasias Hematológicas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Circadianas Period/metabolismo , Animais , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Proteínas de Neoplasias/genética , Proteínas Circadianas Period/genéticaRESUMO
The mortality caused by cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) ranks second among female malignant tumour deaths, but their diagnostic and therapeutic targets are still limited. N6-methyladenosine (m6A) is the most common and extensive modification in mRNA molecules, and its methylation regulators participate in regulating the occurrence and development of many tumours. However, whether m6A RNA methylation regulators can be used as independent prognostic indicators of CESC remains unknown. This study unveiled differential expression of 20 m6A RNA methylation regulators between normal and CESC tumour samples, which RNA sequence data and clinical information were obtained from TCGA database. As a result, five m6A RNA methylation regulators (FTO, HNRNPA2B1, RBM15, IGF2BP1, IGF2BP3) were identified to be significantly linked to CESC tumour status. After Lasso cox regression analysis, six m6A RNA methylation regulators (YTHDC2, YTHDC1, ALKBH5, ZC3H13, RBMX, YTHDF1) were chosen to construct a risk signature. CESC patients were then classified as high-risk and low-risk group based on the median risk score. The overall survival (OS) of the CESC patients in high-risk group was significantly lower than that in low-risk group, and the area under curve (AUC) is 0.718. Moreover, the risk model can be an independent prognosis factors for CESC patients and can predict OS of CESC patients with different clinical factors. In conclusion, m6A RNA methylation regulators are closely correlated with CESC clinical characteristics and the selected six m6A RNA methylation regulators may be useful for CESC patients personalized treatment.
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Proteínas de Ligação a RNA , Adenocarcinoma , Carcinoma de Células Escamosas , Feminino , Humanos , Metilação , PrognósticoRESUMO
BACKGROUND/AIMS: The mechanistic target of rapamycin (mTOR) signaling pathway is essential for angiogenesis and embryonic development. DEP domain-containing mTOR-interacting protein (DEPTOR) is an mTOR binding protein that functions to inhibit the mTOR pathway In vitro experiments suggest that DEPTOR is crucial for vascular endothelial cell (EC) activation and angiogenic responses. However, knowledge of the effects of DEPTOR on angiogenesis in vivo is limited. This study aimed to determine the role of DEPTOR in tissue angiogenesis and to elucidate the molecular mechanisms. METHODS: Cre/loxP conditional gene knockout strategy was used to delete the Deptor gene in mouse vascular ECs. The expression or distribution of cluster of differentiation 31 (CD31), vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1 alpha (HIF-1α) were detected by immunohistochemical staining or western blot. Tube formation assay was used to measure angiogenesis in vitro. RESULTS: Deptor knockdown led to increased expression of CD31, VEGF and HIF-1α in heart, liver, kidney and aorta. After treatment with rapamycin, their expression was significantly down regulated. In vitro, human umbilical vein endothelial cells (HUVECs) were transfected with DEPTOR-specific small interfering RNA (siRNA), which resulted in a significant increase in endothelial tube formation and migration rates. In contrast, DEPTOR overexpression markedly reduced the expression of CD31, VEGF and HIF-1α. CONCLUSIONS: Our findings demonstrated that deletion of the Deptor gene in vascular ECs resulted in upregulated expression of CD31 and HIF-1α, and further stimulated the expression of VEGF which promoted angiogenesis, indicating that disruption of normal angiogenic pathways may occur through hyperactivation of the mTORC1/HIF-1α/VEGF signaling pathway.
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Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Neovascularização Fisiológica , Animais , Aorta/metabolismo , Aorta/patologia , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Camundongos Knockout , Neovascularização Fisiológica/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
In virtualized sensor networks, virtual machines (VMs) share the same hardware for sensing service consolidation and saving power. For those VMs that reside in the same hardware, frequent interdomain data transfers are invoked for data analytics, and sensor collaboration and actuation. Traditional ways of interdomain communications are based on virtual network interfaces of bilateral VMs for data sending and receiving. Since these network communications use TCP/IP (Transmission Control Protocol/Internet Protocol) stacks, they result in lengthy communication paths and frequent kernel interactions, which deteriorate the I/O (Input/Output) performance of involved VMs. In this paper, we propose an optimized interdomain communication approach based on shared memory to improve the interdomain communication performance of multiple VMs residing in the same sensor hardware. In our approach, the sending data are shared in memory pages maintained by the hypervisor, and the data are not transferred through the virtual network interface via a TCP/IP stack. To avoid security trapping, the shared data are mapped in the user space of each VM involved in the communication, therefore reducing tedious system calls and frequent kernel context switches. In implementation, the shared memory is created by a customized shared-device kernel module that has bidirectional event channels between both communicating VMs. For performance optimization, we use state flags in a circular buffer to reduce wait-and-notify operations and system calls during communications. Experimental results show that our proposed approach can provide five times higher throughput and 2.5 times less latency than traditional TCP/IP communication via a virtual network interface.
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Events consist of objects in motion. When objects move, their opaque surfaces reflect light and produce both static image structure and dynamic optic flow. The static and dynamic optical information co-specify events. Patients with age-related macular degeneration (AMD) and amblyopia cannot identify static objects because of weakened image structure. However, optic flow is detectable despite blurry vision because visual motion measurement uses low spatial frequencies. When motion ceases, image structure persists and might preserve properties specified by optic flow. We tested whether optic flow and image structure interact to allow event perception with poor static vision. AMD (Experiment 1), amblyopic (Experiments 2 and 3), and normally sighted observers identified common events from either blurry (Experiments 1 and 2) or clear images (Experiment 3), when either single image frames were presented, a sequence of frames was presented with motion masks, or a sequence of frames was presented with detectable motion. Results showed that with static images, but no motion, events were not perceived well by participants other than controls in Experiment 3. However, with detectable motion, events were perceived. Immediately following this and again after five days, participants were able to identify events from the original static images. So, when image structure information is weak, optic flow compensates for it and enables event perception. Furthermore, weakened static image structure information nevertheless preserves information that was once available in optic flow. The combination is powerful and allows events to be perceived accurately and stably despite blurry vision.
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Ambliopia/fisiopatologia , Degeneração Macular/fisiopatologia , Percepção de Movimento/fisiologia , Fluxo Óptico/fisiologia , Baixa Visão/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Casos e Controles , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: MASM, a novel derivative of matrine, has inhibitory effects on activation of macrophages, dendritic cells, and hepatic stellate cells and binds to ribosomal protein S5 (RPS5). This study was designed to evaluate the effect of MASM on murine-established lethal sepsis and its mechanisms. METHODS: Mouse peritoneal macrophages and RAW264.7 cells that were infected with recombinant lentiviruses encoding shRPS5 were incubated with lipopolysaccharide (LPS) in the absence or presence of MASM in vitro. Endotoxemia induced by LPS injection and sepsis induced by cecal ligation and puncture was followed by MASM treatment. RESULTS: MASM markedly attenuated LPS-induced release and messenger RNA expression of tumor necrosis factor α, interleukin 6, and NO/inducible NO synthase in murine peritoneal macrophages and RAW264.7 cells. Meanwhile, MASM inhibited LPS-induced activation of nuclear factor κB and MAPK pathways. Consistently, RPS5 suppressed LPS-induced inflammatory responses and at least in part mediated the antiinflammatory effect of MASM in vitro. Remarkably, delayed administration of MASM could significantly reduce mortality in mouse sepsis models, which was associated with the reduction in the inflammatory response, the attenuation in multiple organ injury, and the enhanced bacterial clearance. CONCLUSIONS: MASM could be further explored for the treatments of sepsis, especially for administration later after the onset of sepsis.
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Alcaloides/administração & dosagem , Fatores Imunológicos/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/patologia , Quinolizinas/administração & dosagem , Sepse/tratamento farmacológico , Sepse/patologia , Animais , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7/efeitos dos fármacos , Células RAW 264.7/imunologia , Análise de Sobrevida , MatrinasRESUMO
Sulfur mustard (SM) is a vesicating chemical warfare agent used in numerous military conflicts and remains a potential chemical threat to the present day. Exposure to SM causes the depletion of cellular antioxidant thiols, mainly glutathione (GSH), which may lead to a series of SM-associated toxic responses. MSTF is the mixture of salvianolic acids (SA) of Salvia miltiorrhiza and total flavonoids (TFA) of Anemarrhena asphodeloides. SA is the main water-soluble phenolic compound in Salvia miltiorrhiza. TFA mainly includes mangiferin, isomangiferin and neomangiferin. SA and TFA possess diverse activities, including antioxidant and anti-inflammation activities. In this study, we mainly investigated the therapeutic effects of MSTF on SM toxicity in Sprague Dawley rats. Treatment with MSTF 1 h after subcutaneous injection with 3.5 mg/kg (equivalent to 0.7 LD50) SM significantly increased the survival levels of rats and attenuated the SM-induced morphological changes in the testis, small intestine and liver tissues. Treatment with MSTF at doses of 60 and 120 mg/kg caused a significant (p<0.05) reversal in SM-induced GSH depletion. Gene expression profiles revealed that treatment with MSTF had a dramatic effect on gene expression changes caused by SM. Treatment with MSTF prevented SM-induced differential expression of 93.8% (973 genes) of 1037 genes. Pathway enrichment analysis indicated that these genes were mainly involved in a total of 36 pathways, such as the MAPK signaling pathway, pathways in cancer, antigen processing and presentation. These data suggest that MSTF attenuates SM-induced injury by increasing GSH and targeting multiple pathways, including the MAPK signaling pathway, as well as antigen processing and presentation. These results suggest that MSTF has the potential to be used as a potential therapeutic agent against SM injuries.
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Alcenos/farmacologia , Anemarrhena/química , Substâncias para a Guerra Química/toxicidade , Flavonoides/farmacologia , Gás de Mostarda/toxicidade , Polifenóis/farmacologia , Salvia miltiorrhiza/química , Alcenos/química , Animais , Substâncias para a Guerra Química/química , Flavonoides/química , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Polifenóis/química , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testículo/metabolismoRESUMO
The field of large numerical aperture microscopy has witnessed significant advancements in spatial and temporal resolution, as well as improvements in optical microscope imaging quality. However, these advancements have concurrently raised the demand for enhanced precision, extended range, and increased load-bearing capacity in objective motion carrier (OMC). To address this challenge, this study introduces an innovative OMC that employs a ball screw mechanism as its primary driving component. Furthermore, a robust nonlinear motion control strategy has been developed, which integrates fast nonsingular terminal sliding mode, experimental estimation techniques, and adaptive radial basis neural network, to mitigate the impact of nonlinear friction within the ball screw mechanism on motion precision. The stability of the closed-loop control system has been rigorously demonstrated through Lyapunov theory. Compared with other enhanced sliding mode control strategies, the maximum error and root mean square error of this controller are improved by 33% and 34% respectively. The implementation of the novel OMC has enabled the establishment of a high-resolution bio-optical microscope, which has proven its effectiveness in the microscopic imaging of retinal organoids.
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Algoritmos , Microscopia , Movimento (Física) , Redes Neurais de Computação , Microscopia/métodos , Processamento de Imagem Assistida por Computador/métodos , Retina/diagnóstico por imagem , Retina/fisiologiaRESUMO
Two dimensional iron metal-organic framework nanosheet (2D Fe MOF) was facilely synthesized at room temperature by simple stirring of iron salts and terephthalic acid ligand in a mixed solution containing triethylamine. Its morphology and structure were fully characterized by TEM, AFM, XPS and TEM element mapping. Then, its peroxidase-mimicking activity was studied by using H2O2 and 3, 3', 5, 5'- tetramethylbenzidine as substrate. Km and Vmax of 2D Fe MOF towards H2O2 were 0.02 mM and 2.08 × 10-8 M s-1, respectively. Through the formation of cascade reaction between xanthine oxidase and 2D Fe MOF, a visual method for hypoxanthine (Hx) detection was constructed to evaluate aquatic products freshness. After effective validation, this method presented wide linear range (5.0-500.0 µM), low limit of detection (3.29 µM), satisfied accuracy (recovery of 94.78-99.85%), and good selectivity. By using this method, Hx content in shrimp samples at different storage time were determined.
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Ferro , Estruturas Metalorgânicas , Ferro/química , Estruturas Metalorgânicas/química , Colorimetria/métodos , Hipoxantina , Peróxido de Hidrogênio/química , Peroxidases/químicaRESUMO
In addition to size, shape and morphology, enzyme-mimetic property could be efficiently regulated by controlling composition, forming complexes or hybrids, and surface modification. Herein, Pd nanoparticles with an average diameter of 2.52 nm were decorated on ultrathin 2D copper(ii)-porphyrin derived metal-organic framework (MOF) nanosheets by a simple reduction method for catalytic activity regulation. In comparison with other nanozymes, the as-synthesized Pd modified 2D MOF hybrid nanosheets (Pd@Cu-TCPP(Fe)) presented excellent peroxidase-mimic activity, exhibiting an even superior catalytic ability towards H2O2 with a Michaelis-Menten constant as low as 2.33 mM. Based on a cascade reaction between glucose oxidase and Pd@Cu-TCPP(Fe), a colorimetric method for the detection of glucose was established and validated with a wide linear range (0.2-8.0 mM), good recovery (89.5-94.2%) and nice reproducibility (3.65%). All these features guaranteed its excellent ability for glucose determination in human cerebrospinal fluids. This study could offer a valuable reference for constructing novel optical biosensors.
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Immune checkpoint inhibitors currently serve an important role in prolonging patients' overall survival. However, the prognostic signatures of immune checkpoint inhibitors in colorectal cancer (CRC) remain uncertain and more knowledge on the genetic characteristics of colorectal cancer is needed. Patients with CRC from The Cancer Genome Atlas were classified into high-immunity group and low-immunity group based on median scores from single-sample gene set enrichment analysis using the GSVA package. We explored immune status by immune scores, stromal scores and tumor purity scores in ESTIMATE package and surveyed the difference of immune cells distribution with CIBERSORT package. Eighteen genes were selected using the LASSO Cox regression method and a prognostic risk model was constructed. Compared with patients in the low-risk group, those in the high-risk group had a significantly shorter survival time. For assessment of the prognostic validity of the risk model, receiver operating characteristic curves with areas under the curve of 0.769, 0.774 and 0.771 for 1, 3 and 5 years respectively. Differences in molecular mechanisms between high- and low-risk groups were analyzed using the clusterProfiler package. Tumor Immune Dysfunction and Exclusion data were downloaded and analyzed. The top 5 enriched pathways in the high-risk group involved 'calcium signaling', 'dilated cardiomyopathy', 'extracellular matrix receptor interaction', 'hypertrophic cardiomyopathy' and 'neuroactive ligand receptor interaction'. HAMP was identified as a hub gene, which was highly expressed in tumor samples. The results of the present study indicate that the prognostic model based on both immune-related genes and HAMP has the potential to support personalized treatment.
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Metalloporphyrin and gold nanoparticles (AuNPs) were fixed on the surface of hollow zeolite imidazole framework-8 (HZIF-8) by cation exchange and cross-linking reaction. The obtained hybrid nanozyme, Au/HZIF-8@TCPP(Fe), was fully characterized by TEM, HRTEM, EDS element mapping and XPS. Then, its peroxidase-like activity was explored with Km of 1.74 mM and Vmax of 9.60 × 10-8 M·S-1 towards H2O2, indicating excellent catalytic activity. Based on cascade reaction between choline oxidase and Au/HZIF-8@TCPP(Fe), a quick colorimetric method was established for choline detection in infant formula milk powder. After comprehensive verification, this method presented the merits of simple operation, satisfied detection limit (0.05 mM), wide linear range (0.05-2.0 mM), high accuracy (recovery of 92.2%-105.2%) and nice selectivity. This colorimetric method was applied to the determination of choline in milk powders of five brands. Our study could offer valuable reference for finding highly efficient nanozyme and constructing novel optical biosensors.
Assuntos
Nanopartículas Metálicas , Metaloporfirinas , Zeolitas , Animais , Colina , Colorimetria/métodos , Ouro , Humanos , Peróxido de Hidrogênio , Imidazóis , Lactente , Fórmulas Infantis , Limite de Detecção , Leite , Peroxidase , PósRESUMO
The visual system is capable of recognizing objects when object information is widely separated in space, as revealed by the Kanizsa-type illusory contours (ICs). Attentional involvement in perception of ICs is an important topic, and the present study examined whether and how the processing of ICs is interfered with by a distractor. Discrimination between thin and short deformations of an illusory circle was investigated in the absence or presence of a central dynamic patch, with difficulty of discrimination varied in three levels (easy, medium, and hard). Reaction time (RT) was significantly shorter in the absence compared to the presence of the distractor in the easy and medium conditions. Correct rate (CR) was significantly higher in the absence compared to the presence of the distractor in the easy condition, and the magnitude of the difference between CRs of distracted and non-distracted responses significantly reduced as task difficulty increased. These results suggested that perception of ICs is more likely to be vulnerable to distraction when more attentional resources remain available. The present finding supports that attention is engaged in perception of ICs and that distraction of IC processing is associated with perceptual load.
RESUMO
Ultrasmall Au nanoparticles (UsAuNPs) in the size range of 4.0-7.0 nm was successfully immobilized on the surface of 2D metalloporphyrinic metal-organic framework nanosheets (2D MOF). Firstly, The obtained hybrid nanomaterial, UsAuNPs/2D MOF, was fully characterized by TEM, HRTEM, element mapping images and XPS. Then, the peroxidase-like activity of UsAuNPs/2D MOF was comparatively studied with other hybrid nanozyme to explore the influence of AuNPs size on peroxidase-like activity. Further, UsAuNPs/2D MOF with outstanding peroxidase-like activity was selected to form ternary cascade enzyme reaction with acetylcholinesterase (AChE) and choline oxidase (ChOx). Based on the inhibitory effect of organophosphorus pesticides on AChE, a fast and sensitive colorimetric method was established for trichlorfon detection with the advantages of simple operation, low detection limit (1.7 µM), good linear range (1.7-42.4 µM) and high accuracy (recovery rate of 96.6-105.3%). Finally, this method was applied to visual analysis of trichlorfon concentration in tomatoes, cucumbers and eggplants.