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1.
Nature ; 601(7894): 562-567, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35082417

RESUMEN

In conventional superconductors, the phase transition into a zero-resistance and perfectly diamagnetic state is accompanied by a jump in the specific heat and the opening of a spectral gap1. In the high-transition-temperature (high-Tc) cuprates, although the transport, magnetic and thermodynamic signatures of Tc have been known since the 1980s2, the spectroscopic singularity associated with the transition remains unknown. Here we resolve this long-standing puzzle with a high-precision angle-resolved photoemission spectroscopy (ARPES) study on overdoped (Bi,Pb)2Sr2CaCu2O8+δ (Bi2212). We first probe the momentum-resolved electronic specific heat via spectroscopy and reproduce the specific heat peak at Tc, completing the missing link for a holistic description of superconductivity. Then, by studying the full momentum, energy and temperature evolution of the spectra, we reveal that this thermodynamic anomaly arises from the singular growth of in-gap spectral intensity across Tc. Furthermore, we observe that the temperature evolution of in-gap intensity is highly anisotropic in the momentum space, and the gap itself obeys both the d-wave functional form and particle-hole symmetry. These findings support the scenario that the superconducting transition is driven by phase fluctuations. They also serve as an anchor point for understanding the Fermi arc and pseudogap phenomena in underdoped cuprates.

2.
J Cell Physiol ; 239(2): e31163, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38009273

RESUMEN

Many studies have indicated that tumor growth factor-beta (TGF-ß) signaling mediates radiation-induced bystander effects (RIBEs). The primary cilium (PC) coordinates several signaling pathways including TGF-ß signaling to regulate diverse cellular processes. But whether the PC participates in TGF-ß induced RIBEs remains unclear. The cellular levels of TGF-ß1 were detected by western blot analysis and the secretion of TGF-ß1 was measured by ELISA kit. The ciliogenesis was altered by CytoD treatment, STIL siRNA transfection, IFT88 siRNA transfection, or KIF3a siRNA transfection, separately, and was detected by western blot analysis and immunofluorescence staining. G0 /G1 phase cells were arrested by serum starvation and S phase cells were induced by double thymidine block. The TGF-ß1 signaling was interfered by LY2109761, a TGF-ß receptor 1 (TßR1) inhibitor, or TGF-ß1 neutral antibody. The DNA damages were induced by TGF-ß1 or radiated conditional medium (RCM) from irradiated cells and were reflected by p21 expression, 53BP1 foci, and γH2AX foci. Compared with unirradiated control, both A549 and Beas-2B cells expressed and secreted more TGF-ß1 after carbon ion beam or X-ray irradiation. RCM collected from irradiated cells or TGF-ß1 treatment caused an increase of DNA damage in cocultured unirradiated Beas-2B cells while blockage of TGF-ß signaling by TßR1 inhibitor or TGF-ß1 neutral antibody alleviates this phenomenon. IFT88 siRNA or KIF3a siRNA impaired PC formation resulted in an aggravated DNA damage in bystander cells, while elevated PC formation by CytoD or STIL siRNA resulted in a decrease of DNA damage. Furthermore, TGF-ß1 induced more DNA damages in S phases cells which showed lower PC formation rate and less DNA damages in G0 /G1 phase cells which showed higher PC formation rate. This study demonstrates the particular role of primary cilia during RCM induced DNA damages through TGF-ß1 signaling restriction and thereby provides a functional link between primary cilia and RIBEs.


Asunto(s)
Efecto Espectador , Factor de Crecimiento Transformador beta1 , Efecto Espectador/genética , Efecto Espectador/efectos de la radiación , Cilios/metabolismo , ADN , ARN Interferente Pequeño/genética , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Humanos , Línea Celular Tumoral
3.
Rep Prog Phys ; 87(10)2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39260394

RESUMEN

Thechirality-controlled two-mode Lipkin-Meshkov-Glick (LMG) modelsare mimicked in a potential hybrid quantum system, involving two ensembles of solid-state spins coupled to a pair of interconnected surface-acoustic-wave cavities. With the assistance of dichromatic classical optical drives featuring chiral designs, it can simulate two-mode LMG-type long-range spin-spin interactions with left-right asymmetry. For applications, this unconventional LMG model can not only engineer both ensembles of collective spins into two-mode spin-squeezed states but also simulate novel quantum critical phenomena and time crystal behaviors, among others. Since this acoustic-based system can generate ion-trap-like interactions without requiring any additional trapping techniques, our work is considered a fresh attempt at realizing chiral quantum manipulation of spin-spin interactions using acoustic hybrid systems.

4.
Biochem Biophys Res Commun ; 717: 150028, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38714016

RESUMEN

Mycoplasma pneumoniae (MP),as the most commonly infected respiratory pathogen in community-acquired pneumonia in preschool children,has becoming a prominent factor affecting children's respiratory health.Currently, there is a lack of easy, rapid, and accurate laboratory testing program for MP infection, which causes comparatively difficulty for clinical diagnostic.Here,we utilize loop-mediated isothermal amplification (LAMP) to amplify and characterize the P1 gene of MP, combined with nucleic acid lateral flow (NALF) for fast and visuallized detection of MP.Furthermore, we evaluated and analyzed the sensitivity, specificity and methodological consistency of the method.The results showed that the limit of detection(LoD) of MP-LAMP-NALF assay was down to 100 copys per reaction and there was no cross-reactivity with other pathogens infected the respiratory system. The concordance rate between MP-LAMP-NALF assay with quantitative real-time PCR was 94.3 %,which exhibiting excellent testing performance.We make superior the turnaround time of the MP-LAMP-NALF assay, which takes only about 50 min. In addition, there is no need for precision instruments and no restriction on the laboratory site.Collectively, LAMP-NALF assay targeting the P1 gene for Mycoplasma pneumoniae detection was a easy, precise and visual test which could be widely applied in outpatient and emergency departments or primary hospitals.When further optimized, it could be used as "point-of-care testing" of pathogens or multiple testing for pathogens.


Asunto(s)
Técnicas de Diagnóstico Molecular , Mycoplasma pneumoniae , Técnicas de Amplificación de Ácido Nucleico , Neumonía por Mycoplasma , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/métodos , Humanos , Neumonía por Mycoplasma/diagnóstico , Neumonía por Mycoplasma/microbiología , Técnicas de Diagnóstico Molecular/métodos , Sensibilidad y Especificidad , Límite de Detección , ADN Bacteriano/genética
5.
Brief Bioinform ; 23(4)2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35794722

RESUMEN

Drug target discovery is an essential step to reveal the mechanism of action (MoA) underlying drug therapeutic effects and/or side effects. Most of the approaches are usually labor-intensive while unable to identify the tissue-specific interacting targets, especially the targets with weaker drug binding affinity. In this work, we proposed an integrated pipeline, FL-DTD, to predict the drug interacting targets of novel compounds in a tissue-specific manner. This method was built based on a hypothesis that cells under a status of homeostasis would take responses to drug perturbation by activating feedback loops. Therefore, the drug interacting targets can be predicted by analyzing the network responses after drug perturbation. We evaluated this method using the expression data of estrogen stimulation, gene manipulation and drug perturbation and validated its good performance to identify the annotated drug targets. Using STAT3 as a target protein, we applied this method to drug perturbation data of 500 natural compounds and predicted five compounds with STAT3 interacting activities. Experimental assay validated the STAT3-interacting activities of four compounds. Overall, our evaluation suggests that FL-DTD predicts the drug interacting targets with good accuracy and can be used for drug target discovery.


Asunto(s)
Sistemas de Liberación de Medicamentos , Descubrimiento de Drogas , Descubrimiento de Drogas/métodos , Retroalimentación
6.
Appl Environ Microbiol ; : e0111324, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365040

RESUMEN

Heavy ion beam (HIB) irradiation is widely utilized in studies of cosmic rays-induced cellular effects and microbial breeding. Establishing an accurate dose-survival relationship is crucial for selecting the optimal irradiation dose. Typically, after irradiating logarithmic-phase cell suspensions with HIB, the survival fraction (SF) is determined by the ratio of clonal-forming units in irradiated versus control groups. However, our findings indicated that SF measurements were time sensitive. For the Saccharomyces cerevisiae model, the observed SF initially declined and subsequently increased in a eutrophic state; conversely, in an oligotrophic state, it remained relatively stable within 120 minutes. This time effect of SF observations in the eutrophic state can be ascribed to HIB-exposed cells experiencing cell cycle arrest, whereas the control proliferated rapidly, resulting in an over-time disproportionate change in viable cell count. Therefore, an alternative involves irradiating oligotrophic cells, determining SF thereafter, and transferring cells to the eutrophic state to facilitate DNA repair-mutation. Transcriptomic comparisons under these two trophic states yield valuable insights into the DNA damage response. Although DNA repair was postponed in an oligotrophic state, cells proactively mobilized specific repair pathways to advance this process. Effective nutritional supplementation should occur within 120 minutes, beyond this window, a decline in SF indicates an irreversible loss of repair capability. Upon transition to the eutrophic state, S. cerevisiae swiftly adapted and completed the repair. This study helps to minimize time-dependent variability in SF observations and to ensure effective damage repair and mutation in microbial breeding using HIB or other mutagens. It also promotes the understanding of microbial responses to complex environments.IMPORTANCEMutation breeding is a vital means of developing excellent microbial resources. Consequently, understanding the mechanisms through which microorganisms respond to complex environments characterized by mutagens and specific physiological-biochemical states holds significant theoretical and practical values. This study utilized Saccharomyces cerevisiae as a microbial model and highly efficient heavy ion beam (HIB) radiation as a mutagen, it revealed the time dependence of observations of survival fractions (SF) in response to HIB radiation and proposed an alternative to avoid the indeterminacy that this variable brings. Meanwhile, by incorporating an oligotrophic state into the alternative, this study constructed a dynamic map of gene expression during the fast-repair and slow-repair stages. It also highlighted the influence of trophic states on DNA repair. The findings apply to the survival-damage repair-mutation effects of single-celled microorganisms in response to various mutagens and contribute to elucidating the biological mechanisms underlying microbial survival in complex environments.

7.
BMC Gastroenterol ; 24(1): 129, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589828

RESUMEN

BACKGROUND: The HAP, Six-and-Twelve, Up to Seven, and ALBI scores have been substantiated as reliable prognostic markers in patients presenting with intermediate and advanced hepatocellular carcinoma (HCC) undergoing transarterial chemoembolization (TACE) treatment. Given this premise, our research aims to assess the predictive efficacy of these models in patients with intermediate and advanced HCC receiving a combination of TACE and Apatinib. Additionally, we have conducted a meticulous comparative analysis of these four scoring systems to discern their respective predictive capacities and efficacies in combined therapy. METHODS: Performing a retrospective analysis on the clinical data from 200 patients with intermediate and advanced HCC, we studied those who received TACE combined with Apatinib at the First Affiliated Hospital of the University of Science and Technology of China between June 2018 and December 2022. To identify the factors affecting survival, the study performed univariate and multivariate Cox regression analyses, with calculations of four different scores: HAP, Six-and-Twelve, Up to Seven, and ALBI. Lastly, Harrell's C-index was employed to compare the prognostic abilities of these scores. RESULTS: Cox proportional hazards model results revealed that the ALBI score, presence of portal vein tumor thrombus (PVTT, )and tumor size are independent determinants of prognostic survival. The Kaplan-Meier analyses showed significant differences in survival rates among patients classified by the HAP, Six-and-Twelve, Up to Seven, and ALBI scoring methods. Of the evaluated systems, the HAP scoring demonstrated greater prognostic precision, with a Harrell's C-index of 0.742, surpassing the alternative models (P < 0.05). In addition, an analysis of the area under the AU-ROC curve confirms the remarkable superiority of the HAP score in predicting short-term survival outcomes. CONCLUSION: Our study confirms the predictive value of HAP, Six-and-Twelve, Up to Seven, and ALBI scores in intermediate to advanced Hepatocellular Carcinoma (HCC) patients receiving combined Transarterial Chemoembolization (TACE) and Apatinib therapy. Notably, the HAP model excels in predicting outcomes for this specific HCC subgroup.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Piridinas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Quimioembolización Terapéutica/métodos , Estudios Retrospectivos , Pronóstico
8.
Hepatol Res ; 54(4): 358-367, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37924506

RESUMEN

AIM: The study aimed to investigate the clinical features, incidence, pathogenesis, and management of liver abscess after drug-eluting bead transarterial chemoembolization (DEB-TACE) for primary and metastatic hepatic malignant tumors. METHODS: From June 2019 to June 2021, patients with liver abscess after DEB-TACE for primary and metastatic hepatic malignant tumors were reviewed and evaluated at our hospital. Demographic and clinical data, radiological findings, management approaches, and prognosis were retrospectively analyzed. RESULTS: In total, 419 DEB-TACE procedures were carried out in 314 patients with primary and metastatic liver tumors at our medical center. Twelve patients were confirmed to have liver abscesses after DEB-TACE through clinical manifestations, laboratory investigations, and imaging. In this study, the incidence of liver abscess was 3.82% per patient and 2.86% per DEB-TACE procedure. After percutaneous drainage and anti-inflammatory treatments, 10 patients recovered, and the remaining 2 patients died due to direct complications of liver abscess, such as sepsis and multiple organ failure. The mortality rate of liver abscesses after DEB-TACE was 16.7% (2/12). CONCLUSION: The incidence of liver abscess after DEB-TACE is relatively high and can have serious consequences, including death. Potential risk factors could include large tumor size, history of bile duct or tumor resection, history of diabetes, small DEB size (100-300 µm). Sensitive antibiotics therapy and percutaneous abscess aspiration/drainage are effective treatments for liver abscess after DEB-TACE.

9.
Nucleic Acids Res ; 50(5): 2440-2451, 2022 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-35234905

RESUMEN

CUGBP Elav-like family member 1 (CELF1), an RNA-binding protein (RBP), plays important roles in the pathogenesis of diseases such as myotonic dystrophy, liver fibrosis and cancers. However, targeting CELF1 is still a challenge, as RBPs are considered largely undruggable. Here, we discovered that compound 27 disrupted CELF1-RNA binding via structure-based virtual screening and biochemical assays. Compound 27 binds directly to CELF1 and competes with RNA for binding to CELF1. Compound 27 promotes IFN-γ secretion and suppresses TGF-ß1-induced hepatic stellate cell (HSC) activation by inhibiting CELF1-mediated IFN-γ mRNA decay. In vivo, compound 27 attenuates CCl4-induced murine liver fibrosis. Furthermore, the structure-activity relationship analysis was performed and compound 841, a derivative of compound 27, was identified as a selective CELF1 inhibitor. In conclusion, targeting CELF1 RNA-binding activity with small molecules was achieved, which provides a novel strategy for treating liver fibrosis and other CELF1-mediated diseases.


Asunto(s)
Proteínas de Unión al ARN , ARN , Animales , Proteínas CELF1/metabolismo , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/genética , Ratones , Estabilidad del ARN , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
10.
Radiol Med ; 129(1): 14-28, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37863847

RESUMEN

OBJECTIVE: Exploring the efficacy of a Radiological-Clinical (Rad-Clinical) model in predicting prognosis of unresectable hepatocellular carcinoma (HCC) patients after drug eluting beads transcatheter arterial chemoembolization (DEB-TACE) to optimize the targeted sequential treatment. METHODS: In this retrospective analysis, we included 202 patients with unresectable HCC who received DEB-TACE treatment in 17 institutions from June 2018 to December 2022. Progression-free survival (PFS)-related radiomics features were computationally extracted from HCC patients to build a radiological signature (Rad-signature) model with least absolute shrinkage and selection operator regression. A Rad-Clinical model for postoperative PFS was further constructed according to the Rad-signature and clinical variables by Cox regression analysis. It was presented as a nomogram and evaluated by receiver operating characteristic curves, calibration curves, and decision curve analysis. And further evaluate the application value of Rad-Clinical model in clinical stages and targeted sequential therapy of HCC. RESULTS: Tumor size, Barcelona Clinic Liver Cancer (BCLC) stage, and radiomics score (Rad-score) were found to be independent risk factors for PFS after DEB-TACE treatment for unresectable HCC, with the Rad-Clinical model being the greatest predictor of PFS in these patients (hazard ratio: 2.08; 95% confidence interval: 1.56-2.78; P < 0.001) along with high 6 months, 12 months, 18 months, and 24 months area under the curves of 0.857, 0.810, 0.843, and 0.838, respectively. In addition, compared to the radiomics and clinical nomograms, the Radiological-Clinical nomogram also significantly improved the classification accuracy for PFS outcomes, based on the net reclassification improvement (45.2%, 95% CI 0.260-0.632, p < 0.05) and integrated discrimination improvement (14.9%, 95% CI 0.064-0.281, p < 0.05). Based on this model, low-risk patients had higher PFS than high-risk patients in BCLC-B and C stages (P = 0.021). Targeted sequential therapy for patients with high and low-risk HCC in BCLC-B stage exhibited significant benefits (P = 0.018, P = 0.012), but patients with high-risk HCC in BCLC-C stage did not benefit much (P = 0.052). CONCLUSION: The Rad-Clinical model may be favorable for predicting PFS in patients with unresectable HCC treated with DEB-TACE and for identifying patients who may benefit from targeted sequential therapy.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Nomogramas , Estudios Retrospectivos , Terapia Molecular Dirigida , Resultado del Tratamiento
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