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1.
BMC Cancer ; 23(1): 953, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37814228

RESUMEN

BACKGROUND: Small (< 4 cm) clear cell renal cell carcinoma (ccRCC) is the most common type of small renal cancer and its prognosis is poor. However, conventional radiological characteristics obtained by computed tomography (CT) are not sufficient to predict the nuclear grade of small ccRCC before surgery. METHODS: A total of 113 patients with histologically confirmed ccRCC were randomly assigned to the training set (n = 67) and the testing set (n = 46). The baseline and CT imaging data of the patients were evaluated statistically to develop a clinical model. A radiomics model was created, and the radiomics score (Rad-score) was calculated by extracting radiomics features from the CT images. Then, a clinical radiomics nomogram was developed using multivariate logistic regression analysis by combining the Rad-score and critical clinical characteristics. The receiver operating characteristic (ROC) curve was used to evaluate the discrimination of small ccRCC in both the training and testing sets. RESULTS: The radiomics model was constructed using six features obtained from the CT images. The shape and relative enhancement value of the nephrographic phase (REV of the NP) were found to be independent risk factors in the clinical model. The area under the curve (AUC) values for the training and testing sets for the clinical radiomics nomogram were 0.940 and 0.902, respectively. Decision curve analysis (DCA) revealed that the radiomics nomogram model was a better predictor, with the highest degree of coincidence. CONCLUSION: The CT-based radiomics nomogram has the potential to be a noninvasive and preoperative method for predicting the WHO/ISUP grade of small ccRCC.


Asunto(s)
Carcinoma de Células Renales , Carcinoma de Células Pequeñas , Neoplasias Renales , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/cirugía , Nomogramas , Tomografía Computarizada por Rayos X , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Organización Mundial de la Salud , Estudios Retrospectivos
2.
Radiol Med ; 128(11): 1386-1397, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37597124

RESUMEN

PURPOSE: To develop a radiomics nomogram based on computed tomography (CT) to estimate progression-free survival (PFS) in patients with small cell lung cancer (SCLC) and assess its incremental value to the clinical risk factors for individual PFS estimation. METHODS: 558 patients with pathologically confirmed SCLC were retrospectively recruited from three medical centers. A radiomics signature was generated by using the Pearson correlation analysis, univariate Cox analysis, and multivariate Cox analysis. Association of the radiomics signature with PFS was evaluated. A radiomics nomogram was developed based on the radiomics signature, then its calibration, discrimination, reclassification, and clinical usefulness were evaluated. RESULTS: In total, 6 CT radiomics features were finally selected. The radiomics signature was significantly associated with PFS (hazard ratio [HR] 4.531, 95% confidence interval [CI] 3.524-5.825, p < 0.001). Incorporating the radiomics signature into the radiomics nomogram resulted in better performance for the estimation of PFS (concordance index [C-index] 0.799) than with the clinical nomogram (C-index 0.629), as well as high 6 months and 12 months area under the curves of 0.885 and 0.846, respectively. Furthermore, the radiomics nomogram also significantly improved the classification accuracy for PFS outcomes, based on the net reclassification improvement (33.7%, 95% CI 0.216-0.609, p < 0.05) and integrated discrimination improvement (22.7%, 95% CI 0.168-0.278, p < 0.05). Decision curve analysis demonstrated that in terms of clinical usefulness, the radiomics nomogram outperformed the clinical nomogram. CONCLUSION: A CT-based radiomics nomogram exhibited a promising performance for predicting PFS in patients with SCLC, which could provide valuable information for individualized treatment.


Asunto(s)
Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Nomogramas , Neoplasias Pulmonares/diagnóstico por imagen , Carcinoma Pulmonar de Células Pequeñas/diagnóstico por imagen , Supervivencia sin Progresión , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
3.
Eur Radiol ; 32(10): 6628-6636, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35857074

RESUMEN

OBJECTIVES: Mucosal healing (MH) is currently the gold standard in Crohn's disease (CD) management. Noninvasive assessment of MH in CD patients is increasingly a concern of clinicians. METHODS: This retrospective study included 106 patients with confirmed CD who were divided into a training cohort (n = 73) and a testing cohort (n = 33). Patient demographics were evaluated to establish a clinical model. Radiomics features were extracted from computed tomography enterography (CTE) images. A radiomics signature was constructed, and a radiomics score (Rad-score) was calculated by using the radiomics signature-based formula. A clinical radiomics nomogram was then built by incorporating the Rad-score and significant clinical features. The diagnostic performance of the three models was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Of the 106 patients with CD, 37 exhibited MH after 26 weeks of infliximab (IFX) treatment. The area under the ROC curve (AUC) of the clinical radiomics nomogram for distinguishing MH from non-MH, which was based on the disease duration and Rad-score, was 0.880 (95% confidence interval [CI]: 0.809-0.943) in the training cohort and 0.877 (95% CI: 0.745-0.983) in the testing cohort. Decision curve analysis (DCA) confirmed the clinical utility of the clinical radiomics nomogram. CONCLUSIONS: This is a preliminary study suggesting that this CTE-based radiomics model has potential value for predicting MH in CD patients. A nomogram constructed by combining radiomics signatures and clinical features can help clinicians select appropriate therapeutic strategies for CD patients. KEY POINTS: • The disease duration (odds ratio (OR) = 0.969, 95% confidence interval (CI) = 0.943-0.995, p = 0.021) was an independent predictor of MH in the clinical model. • The AUC of the radiomics model constructed by the five radiomics features was 0.846 (95% CI: 0.759-0.921) in the training cohort and 0.817 (95% CI: 0.665-0.945) in the testing cohort for differentiating MH from non-MH. • The AUC of the clinical radiomics nomogram was 0.880 (95% CI: 0.809-0.943) in the training cohort and 0.877 (95% CI: 0.745-0.983) in the testing cohort for distinguishing MH from non-MH.


Asunto(s)
Enfermedad de Crohn , Nomogramas , Enfermedad de Crohn/diagnóstico por imagen , Enfermedad de Crohn/tratamiento farmacológico , Humanos , Infliximab/uso terapéutico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
4.
J Nanobiotechnology ; 20(1): 379, 2022 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-35964123

RESUMEN

BACKGROUND: Disruption of the postsynaptic density protein-95 (PSD95)-neuronal nitric oxide synthase (nNOS) coupling is an effective way to treat ischemic stroke, however, it still faces some challenges, especially lack of satisfactory PSD95-nNOS uncouplers and the efficient high throughput screening model to discover them. RESULTS: Herein, the multifunctional metal-organic framework (MMOF) nanoparticles as a new screening system were innovatively fabricated via layer-by-layer self-assembly in which His-tagged nNOS was selectively immobilized on the surface of magnetic MOF, and then PSD95 with green fluorescent protein (GFP-PSD95) was specifically bound on it. It was found that MMOF nanoparticles not only exhibited the superior performances including the high loading efficiency, reusability, and anti-interference ability, but also possessed the good fluorescent sensitivity to detect the coupled GFP-PSD95. After MMOF nanoparticles interacted with the uncouplers, they would be rapidly separated from uncoupled GFP-PSD95 by magnet, and the fluorescent intensities could be determined to assay the uncoupling efficiency at high throughput level. CONCLUSIONS: In conclusion, MMOF nanoparticles were successfully fabricated and applied to screen the natural actives as potential PSD95-nNOS uncouplers. Taken together, our newly developed method provided a new material as a platform for efficiently discovering PSD95-nNOS uncouplers for stoke treatment.


Asunto(s)
Estructuras Metalorgánicas , Nanopartículas , Accidente Cerebrovascular , Animales , Homólogo 4 de la Proteína Discs Large/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Ratas , Ratas Sprague-Dawley , Factores de Transcripción
5.
J Proteome Res ; 18(10): 3715-3730, 2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-31442056

RESUMEN

Ligand binding to the cell surface receptors initiates signaling cascades that are commonly transduced through a protein-protein interaction (PPI) network to activate a plethora of response pathways. However, tools to capture the membrane PPI network are lacking. Here, we describe a cross-linking-aided mass spectrometry workflow for isolation and identification of signal-dependent epidermal growth factor receptor (EGFR) proteome. We performed protein cross-linking in cell culture at various time points following EGF treatment, followed by immunoprecipitation of endogenous EGFR and analysis of the associated proteins by quantitative mass spectrometry. We identified 140 proteins with high confidence during a 2 h time course by data-dependent acquisition and further validated the results by parallel reaction monitoring. A large proportion of proteins in the EGFR proteome function in endocytosis and intracellular protein transport. The EGFR proteome was highly dynamic with distinct temporal behavior; 10 proteins that appeared in all time points constitute the core proteome. Functional characterization showed that loss of the FYVE domain-containing proteins altered the EGFR intracellular distribution but had a minor effect on EGFR proteome or signaling. Thus, our results suggest that the EGFR proteome include functional regulators that influence EGFR signaling and bystanders that are captured as the components of endocytic vesicles. The high-resolution spatiotemporal information of these molecules facilitates the delineation of many pathways that could determine the strength and duration of the signaling, as well as the location and destination of the receptor.


Asunto(s)
Mapeo de Interacción de Proteínas/métodos , Proteoma/metabolismo , Transducción de Señal , Línea Celular , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Humanos , Inmunoprecipitación , Espectrometría de Masas , Transporte de Proteínas , Factores de Tiempo , Flujo de Trabajo
6.
Plant Mol Biol ; 101(1-2): 203-220, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31297725

RESUMEN

KEY MESSAGE: Here, a functional characterization of a wheat MSR has been presented: this protein makes a contribution to the plant's tolerance of abiotic stress, acting through its catalytic capacity and its modulation of ROS and ABA pathways. The molecular mechanism and function of certain members of the methionine sulfoxide reductase (MSR) gene family have been defined, however, these analyses have not included the wheat equivalents. The wheat MSR gene TaMSRA4.1 is inducible by salinity and drought stress and in this study, we demonstrate that its activity is restricted to the Met-S-SO enantiomer, and its subcellular localization is in the chloroplast. Furthermore, constitutive expression of TaMSRA4.1 enhanced the salinity and drought tolerance of wheat and Arabidopsis thaliana. In these plants constitutively expressing TaMSRA4.1, the accumulation of reactive oxygen species (ROS) was found to be influenced through the modulation of genes encoding proteins involved in ROS signaling, generation and scavenging, while the level of endogenous abscisic acid (ABA), and the sensitivity of stomatal guard cells to exogenous ABA, was increased. A yeast two-hybrid screen, bimolecular fluorescence complementation and co-immunoprecipitation assays demonstrated that heme oxygenase 1 (HO1) interacted with TaMSRA4.1, and that this interaction depended on a TaHO1 C-terminal domain. In plants subjected to salinity or drought stress, TaMSRA4.1 reversed the oxidation of TaHO1, activating ROS and ABA signaling pathways, but not in the absence of HO1. The aforementioned properties advocate TaMSRA4.1 as a candidate for plant genetic enhancement.


Asunto(s)
Hemo-Oxigenasa 1/metabolismo , Metionina Sulfóxido Reductasas/metabolismo , Transducción de Señal , Estrés Fisiológico , Triticum/enzimología , Ácido Abscísico/metabolismo , Arabidopsis/enzimología , Arabidopsis/genética , Arabidopsis/fisiología , Sequías , Perfilación de la Expresión Génica , Hemo-Oxigenasa 1/genética , Metionina Sulfóxido Reductasas/genética , Oxidación-Reducción , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Salinidad , Tolerancia a la Sal , Plantones/enzimología , Plantones/genética , Plantones/fisiología , Triticum/genética , Triticum/fisiología , Técnicas del Sistema de Dos Híbridos
7.
Plant Cell Environ ; 42(5): 1486-1502, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30577086

RESUMEN

In animals, the Sep15 protein participates in disease resistance, growth, and development, but the function of its plant homologues remains unclear. Here, the function of maize Sep15 was analysed by characterization of two independent Sep15-like loss-of-function mutants. In the absence of ZmSep15-like, seedling tolerance to both water and salinity stress was compromised. The mutants experienced a heightened level of endoplasmic reticulum stress, and over-accumulated reactive oxygen species, resulting in leaf necrosis. Characterization of Arabidopsis thaliana atsep15 mutant as well as like with ectopic expression of ZmSep15-like indicated that ZmSep15-like contributed to tolerance of both osmotic and salinity stress. ZmSep15-like interacted physically with UDP-glucose: glycoprotein glucosyltransferase1 (UGGT1). When the interaction was disrupted, the response to both osmotic and salinity stresses was impaired in maize or Arabidopsis. Co-expressing ZmUGGT1 and ZmUGGT2 enhanced the tolerance of A. thaliana to both stressors, indicating a functional interaction between them. Together, the data indicated that plants Sep15-like proteins promote osmotic and salinity stress resistance by influencing endoplasmic reticulum stress response and reactive oxygen species level.


Asunto(s)
Glucosiltransferasas/metabolismo , Osmorregulación , Presión Osmótica/fisiología , Zea mays , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Retículo Endoplásmico/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/genética , Osmorregulación/genética , Osmorregulación/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés Salino/fisiología , Estrés Fisiológico , Zea mays/metabolismo
8.
Development ; 141(11): 2271-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24803588

RESUMEN

Despite the importance of taste in determining nutrient intake, our understanding of the processes that control the development of the peripheral taste system is lacking. Several early regulators of taste development have been identified, including sonic hedgehog, bone morphogenetic protein 4 and multiple members of the Wnt/ß-catenin signaling pathway. However, the regulation of these factors, including their induction, remains poorly understood. Here, we identify a crucial role for the Wilms' tumor 1 protein (WT1) in circumvallate (CV) papillae development. WT1 is a transcription factor that is important in the normal development of multiple tissues, including both the olfactory and visual systems. In mice, WT1 expression is detectable by E12.5, when the CV taste placode begins to form. In mice lacking WT1, the CV fails to develop normally and markers of early taste development are dysregulated compared with wild type. We demonstrate that expression of the WT1 target genes Lef1, Ptch1 and Bmp4 is significantly reduced in developing tongue tissue derived from Wt1 knockout mice and that, in normal tongue, WT1 is bound to the promoter regions of these genes. Moreover, siRNA knockdown of WT1 in cultured taste cells leads to a reduction in the expression of Lef1 and Ptch1. Our data identify WT1 as a crucial transcription factor in the development of the CV through the regulation of multiple signaling pathways that have established roles in the formation and patterning of taste placodes.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Papilas Gustativas/embriología , Gusto/fisiología , Lengua/embriología , Proteínas WT1/metabolismo , Animales , Factor de Unión 1 al Potenciador Linfoide/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Patched , Receptor Patched-1 , Fenotipo , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Factores de Tiempo
9.
Nature ; 471(7337): 240-4, 2011 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-21390131

RESUMEN

DNA replication and repair in mammalian cells involves three distinct DNA ligases: ligase I (Lig1), ligase III (Lig3) and ligase IV (Lig4). Lig3 is considered a key ligase during base excision repair because its stability depends upon its nuclear binding partner Xrcc1, a critical factor for this DNA repair pathway. Lig3 is also present in the mitochondria, where its role in mitochondrial DNA (mtDNA) maintenance is independent of Xrcc1 (ref. 4). However, the biological role of Lig3 is unclear as inactivation of murine Lig3 results in early embryonic lethality. Here we report that Lig3 is essential for mtDNA integrity but dispensable for nuclear DNA repair. Inactivation of Lig3 in the mouse nervous system resulted in mtDNA loss leading to profound mitochondrial dysfunction, disruption of cellular homeostasis and incapacitating ataxia. Similarly, inactivation of Lig3 in cardiac muscle resulted in mitochondrial dysfunction and defective heart-pump function leading to heart failure. However, Lig3 inactivation did not result in nuclear DNA repair deficiency, indicating essential DNA repair functions of Xrcc1 can occur in the absence of Lig3. Instead, we found that Lig1 was critical for DNA repair, but acted in a cooperative manner with Lig3. Additionally, Lig3 deficiency did not recapitulate the hallmark features of neural Xrcc1 inactivation such as DNA damage-induced cerebellar interneuron loss, further underscoring functional separation of these DNA repair factors. Therefore, our data reveal that the critical biological role of Lig3 is to maintain mtDNA integrity and not Xrcc1-dependent DNA repair.


Asunto(s)
Núcleo Celular/genética , ADN Ligasas/metabolismo , Reparación del ADN , ADN Mitocondrial/metabolismo , Proteínas de Unión al ADN/metabolismo , Animales , Ataxia/patología , Ataxia/fisiopatología , Biocatálisis , Supervivencia Celular , Células Cultivadas , Daño del ADN , ADN Ligasa (ATP) , ADN Ligasas/deficiencia , ADN Ligasas/genética , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Genes Esenciales , Corazón/fisiología , Corazón/fisiopatología , Interneuronas/enzimología , Interneuronas/patología , Ratones , Mitocondrias/enzimología , Mitocondrias/genética , Mitocondrias/patología , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Miocardio/enzimología , Miocardio/patología , Sistema Nervioso/enzimología , Sistema Nervioso/patología , Fenotipo , Proteínas de Unión a Poli-ADP-Ribosa , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X , Proteínas de Xenopus
10.
Nature ; 471(7337): 245-8, 2011 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-21390132

RESUMEN

Mammalian cells have three ATP-dependent DNA ligases, which are required for DNA replication and repair. Homologues of ligase I (Lig1) and ligase IV (Lig4) are ubiquitous in Eukarya, whereas ligase III (Lig3), which has nuclear and mitochondrial forms, appears to be restricted to vertebrates. Lig3 is implicated in various DNA repair pathways with its partner protein Xrcc1 (ref. 1). Deletion of Lig3 results in early embryonic lethality in mice, as well as apparent cellular lethality, which has precluded definitive characterization of Lig3 function. Here we used pre-emptive complementation to determine the viability requirement for Lig3 in mammalian cells and its requirement in DNA repair. Various forms of Lig3 were introduced stably into mouse embryonic stem (mES) cells containing a conditional allele of Lig3 that could be deleted with Cre recombinase. With this approach, we find that the mitochondrial, but not nuclear, Lig3 is required for cellular viability. Although the catalytic function of Lig3 is required, the zinc finger (ZnF) and BRCA1 carboxy (C)-terminal-related (BRCT) domains of Lig3 are not. Remarkably, the viability requirement for Lig3 can be circumvented by targeting Lig1 to the mitochondria or expressing Chlorella virus DNA ligase, the minimal eukaryal nick-sealing enzyme, or Escherichia coli LigA, an NAD(+)-dependent ligase. Lig3-null cells are not sensitive to several DNA-damaging agents that sensitize Xrcc1-deficient cells. Our results establish a role for Lig3 in mitochondria, but distinguish it from its interacting protein Xrcc1.


Asunto(s)
ADN Ligasas/metabolismo , Reparación del ADN , ADN Mitocondrial/metabolismo , Proteínas de Unión al ADN/metabolismo , Mitocondrias/enzimología , Mitocondrias/genética , Animales , Biocatálisis , Supervivencia Celular , Daño del ADN , ADN Ligasa (ATP) , ADN Ligasas/química , ADN Ligasas/deficiencia , ADN Ligasas/genética , Células Madre Embrionarias/metabolismo , Genes Esenciales , Prueba de Complementación Genética , Humanos , Ratones , Mitocondrias/patología , Proteínas de Unión a Poli-ADP-Ribosa , Estructura Terciaria de Proteína , Intercambio de Cromátides Hermanas/efectos de los fármacos , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X , Proteínas de Xenopus
11.
Biomed Chromatogr ; 30(2): 117-25, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26037609

RESUMEN

A novel molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization with baicalein (BAI) as the template and used as solid-phase extraction (SPE) adsorbent, aiming at the affinity isolation and selective knockout of BAI from Scutellaria baicalensis Georgi (SB). We used computational simulation to predict the optimal functional monomer, polymerization solvent and molar ratio of template to functional monomer. Characterization and performance tests revealed that MIP exhibited uniform spherical morphology, rapid binding kinetics, and higher adsorption capacity for BAI compared with nonimprinted polymer (NIP). The application of MIP in SPE coupled with high-performance liquid chromatography to extract BAI from SB showed excellent recovery (94.3%) and purity (97.0%). Not only the single BAI compound, but also the BAI-removed SB extract was obtained by one-step process. This new method is useful for isolation and knockout of key bioactive compounds from herbal medicines.


Asunto(s)
Flavanonas/aislamiento & purificación , Impresión Molecular/métodos , Scutellaria baicalensis/química , Extracción en Fase Sólida/métodos , Simulación por Computador , Flavanonas/análisis , Flavanonas/química , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
12.
Anal Bioanal Chem ; 407(2): 509-19, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25395202

RESUMEN

Highly selective molecularly imprinted mesoporous silica polymer (SBA-15@MIP) for baicalein (BAI) extraction was synthesized using a surface molecular imprinting technique on the SBA-15 supporter. Computational simulation was used to predict the optimal functional monomer for the rational design of SBA-15@MIP. Meanwhile, high adsorption capacity was obtained when a suitable yield of molecularly imprinted polymers (MIPs) layer was grafted onto the surface of SBA-15. Characterization and performance tests of the obtained polymer revealed that SBA-15@MIP possessed a highly ordered mesoporous structure, reached saturated adsorption within 60 min, and exhibited higher sorption capacity to the target molecule BAI compared with non-imprinted mesoporous silica polymer (SBA-15@NIP) and SBA-15. Finally, SBA-15@MIP was successfully applied to solid-phase extraction (SPE) coupled with high-performance liquid chromatography and ultraviolet detection (HPLC-UV) for the determination of trace BAI in plasma samples. Mean recoveries of BAI through the molecularly imprinted solid-phase extraction (MISPE) sorbent, non-imprinted solid-phase extraction (NISPE) sorbent, and SBA-15 solid-phase extraction (SBA-15-SPE) sorbent were 94.4, 22.7, and 10.7 %, respectively, and the relative standard deviations were 2.9, 2.6, and 3.6 %, respectively. These results reveal that SBA-15@MIP as a SPE sorbent has good applicability to selectively separate and enrich trace BAI from complex samples.


Asunto(s)
Flavanonas/sangre , Flavanonas/aislamiento & purificación , Impresión Molecular/métodos , Dióxido de Silicio/química , Extracción en Fase Sólida/métodos , Adsorción , Animales , Cromatografía Líquida de Alta Presión/métodos , Humanos , Microscopía Electrónica de Rastreo , Polímeros/síntesis química , Polímeros/química , Ratas , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Rayos Ultravioleta
13.
Zhongguo Zhong Yao Za Zhi ; 40(9): 1718-22, 2015 May.
Artículo en Zh | MEDLINE | ID: mdl-26323135

RESUMEN

Taking mesoporous molecular sieve MCM-41 as a substrate, baicalin (BA) as template, acrylamide (AM) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linking agent, ethanol as solvent, under thermal polymerization initiator of azobis isobutyronitrilo (AIBN) , a kind of selective recognition of baicalin surface molecularly imprinted polymer was synthesized. The surface morphologies and characteristics of the MIPs were characterized by infrared spectroscopy (IR) and transmission electron microscope (TEM). The adsorption properties of polymer microsphere for the template were tested by the dynamic adsorption equilibrium experiments and static adsorption equilibrium experiments. The experiment showed that the imprinting process was successfully and the well-ordered one-dimensional pore structure of MCM-41 was still preserved. Furthermore, molecularly imprinted polymers had higher selective ability for BA, then provided a new method for the efficient separation and enrichment of baicalin active ingredients from medicinal plants Scutellaria baicalensis.


Asunto(s)
Medicamentos Herbarios Chinos/aislamiento & purificación , Flavonoides/química , Flavonoides/aislamiento & purificación , Polímeros/síntesis química , Scutellaria baicalensis/química , Adsorción , Medicamentos Herbarios Chinos/química , Impresión Molecular , Polimerizacion , Polímeros/química , Porosidad
14.
Analyst ; 139(22): 5785-92, 2014 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-25148475

RESUMEN

A novel molecular imprinted sensor based on CdTe@SiO2 quantum dots (QDs) was developed for norepinephrine (NE) recognition. The molecularly imprinted polymer (MIP) on the surface of CdTe@SiO2 QDs (CdTe@SiO2@MIP) was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy and fluorescence spectroscopy. The synthesized nanosensor had a distinguished selectivity and high binding affinity to NE. Under optimal conditions, the relative fluorescence intensity of CdTe@SiO2@MIP linearly decreased with increase of the concentration of NE in the range of 0.04-10 µM. The limit of detection was 8 nM (3σ/K). The proposed method was applied to the analysis of NE in rat plasma, and the result obtained by the method was in good agreement with that assayed by the fluorescence derivatization method. The method developed is simple, fast, and can be applied to the determination of NE in biological samples.


Asunto(s)
Compuestos de Cadmio/química , Colorantes Fluorescentes/química , Impresión Molecular , Norepinefrina/análisis , Polímeros/química , Puntos Cuánticos , Dióxido de Silicio/química , Telurio/química , Límite de Detección , Microscopía Electrónica de Transmisión , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier
15.
PLoS Genet ; 7(6): e1002080, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21655080

RESUMEN

Nonhomologous end-joining (NHEJ) is the primary DNA repair pathway thought to underlie chromosomal translocations and other genomic rearrangements in somatic cells. The canonical NHEJ pathway, including DNA ligase IV (Lig4), suppresses genomic instability and chromosomal translocations, leading to the notion that a poorly defined, alternative NHEJ (alt-NHEJ) pathway generates these rearrangements. Here, we investigate the DNA ligase requirement of chromosomal translocation formation in mouse cells. Mammals have two other DNA ligases, Lig1 and Lig3, in addition to Lig4. As deletion of Lig3 results in cellular lethality due to its requirement in mitochondria, we used recently developed cell lines deficient in nuclear Lig3 but rescued for mitochondrial DNA ligase activity. Further, zinc finger endonucleases were used to generate DNA breaks at endogenous loci to induce translocations. Unlike with Lig4 deficiency, which causes an increase in translocation frequency, translocations are reduced in frequency in the absence of Lig3. Residual translocations in Lig3-deficient cells do not show a bias toward use of pre-existing microhomology at the breakpoint junctions, unlike either wild-type or Lig4-deficient cells, consistent with the notion that alt-NHEJ is impaired with Lig3 loss. By contrast, Lig1 depletion in otherwise wild-type cells does not reduce translocations or affect microhomology use. However, translocations are further reduced in Lig3-deficient cells upon Lig1 knockdown, suggesting the existence of two alt-NHEJ pathways, one that is biased toward microhomology use and requires Lig3 and a back-up pathway which does not depend on microhomology and utilizes Lig1.


Asunto(s)
ADN Ligasas/metabolismo , Translocación Genética , Animales , Secuencia de Bases , Núcleo Celular/metabolismo , ADN Ligasa (ATP) , ADN Ligasas/genética , Reparación del ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Ratones , Modelos Genéticos , Datos de Secuencia Molecular , Proteínas de Unión a Poli-ADP-Ribosa , Transfección , Proteínas de Xenopus
16.
Abdom Radiol (NY) ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38480547

RESUMEN

OBJECTIVE: To demonstrate the clinical advantages of a deep-learning image reconstruction (DLIR) in low-dose dual-energy computed tomography enterography (DECTE) by comparing images with standard-dose adaptive iterative reconstruction-Veo (ASIR-V) images. METHODS: In this Institutional review board approved prospective study, 86 participants who underwent DECTE were enrolled. The early-enteric phase scan was performed using standard-dose (noise index: 8) and images were reconstructed at 5 mm and 1.25 mm slice thickness with ASIR-V at a level of 40% (ASIR-V40%). The late-enteric phase scan used low-dose (noise index: 12) and images were reconstructed at 1.25 mm slice thickness with ASIR-V40%, and DLIR at medium (DLIR-M) and high (DLIR-H). The 70 keV monochromatic images were used for image comparison and analysis. For objective assessment, image noise, artifact index, SNR and CNR were measured. For subjective assessment, subjective noise, image contrast, bowel wall sharpness, mesenteric vessel clarity, and small structure visibility were scored by two radiologists blindly. Radiation dose was compared between the early- and late-enteric phases. RESULTS: Radiation dose was reduced by 50% in the late-enteric phase [(6.31 ± 1.67) mSv] compared with the early-enteric phase [(3.01 ± 1.09) mSv]. For the 1.25 mm images, DLIR-M and DLIR-H significantly improved both objective and subjective image quality compared to those with ASIR-V40%. The low-dose 1.25 mm DLIR-H images had similar image noise, SNR, CNR values as the standard-dose 5 mm ASIR-V40% images, but significantly higher scores in image contrast [5(5-5), P < 0.05], bowel wall sharpness [5(5-5), P < 0.05], mesenteric vessel clarity [5(5-5), P < 0.05] and small structure visibility [5(5-5), P < 0.05]. CONCLUSIONS: DLIR significantly reduces image noise at the same slice thickness, but significantly improves spatial resolution and lesion conspicuity with thinner slice thickness in DECTE, compared to conventional ASIR-V40% 5 mm images, all while providing 50% radiation dose reduction.

17.
Radiother Oncol ; 195: 110221, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38479441

RESUMEN

BACKGROUND AND PURPOSE: To develop a computed tomography (CT)-based deep learning model to predict overall survival (OS) among small-cell lung cancer (SCLC) patients and identify patients who could benefit from prophylactic cranial irradiation (PCI) based on OS signature risk stratification. MATERIALS AND METHODS: This study retrospectively included 556 SCLC patients from three medical centers. The training, internal validation, and external validation cohorts comprised 309, 133, and 114 patients, respectively. The OS signature was built using a unified fully connected neural network. A deep learning model was developed based on the OS signature. Clinical and combined models were developed and compared with a deep learning model. Additionally, the benefits of PCI were evaluated after stratification using an OS signature. RESULTS: Within the internal and external validation cohorts, the deep learning model (concordance index [C-index] 0.745, 0.733) was far superior to the clinical model (C-index: 0.635, 0.630) in predicting OS, but slightly worse than the combined model (C-index: 0.771, 0.770). Additionally, the deep learning model had excellent calibration, clinical usefulness, and improved accuracy in classifying survival outcomes. Remarkably, patients at high risk had a survival benefit from PCI in both the limited and extensive stages (all P < 0.05), whereas no significant association was observed in patients at low risk. CONCLUSIONS: The CT-based deep learning model exhibited promising performance in predicting the OS of SCLC patients. The OS signature may aid in individualized treatment planning to select patients who may benefit from PCI.


Asunto(s)
Irradiación Craneana , Aprendizaje Profundo , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Tomografía Computarizada por Rayos X , Humanos , Carcinoma Pulmonar de Células Pequeñas/radioterapia , Carcinoma Pulmonar de Células Pequeñas/mortalidad , Carcinoma Pulmonar de Células Pequeñas/diagnóstico por imagen , Carcinoma Pulmonar de Células Pequeñas/patología , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico por imagen , Estudios Retrospectivos , Masculino , Femenino , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Irradiación Craneana/métodos , Anciano , Tasa de Supervivencia
18.
JMIR Form Res ; 7: e42346, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37018026

RESUMEN

BACKGROUND: As a popular social networking platform for sharing short videos, TikTok has been widely used for sharing e-cigarettes or vaping-related videos, especially among the youth. OBJECTIVE: This study aims to characterize e-cigarette or vaping-related videos and their user engagement on TikTok through descriptive analysis. METHODS: From TikTok, a total of 417 short videos, posted between October 4, 2018, and February 27, 2021, were collected using e-cigarette or vaping-related hashtags. Two human coders independently hand-coded the video category and the attitude toward vaping (provaping or antivaping) for each vaping-related video. The social media user engagement measures (eg, the comment count, like count, and share count) for each video category were compared within provaping and antivaping groups. The user accounts posting these videos were also characterized. RESULTS: Among 417 vaping-related TikTok videos, 387 (92.8%) were provaping, and 30 (7.2%) were antivaping videos. Among provaping TikTok videos, the most popular category is vaping tricks (n=107, 27.65%), followed by advertisement (n=85, 21.95%), customization (n=75, 19.38%), TikTok trend (n=70, 18.09%), others (n=44, 11.37%), and education (n=6, 1.55%). By comparison, videos showing the TikTok trend had significantly higher user engagement (like count per video) than other provaping videos. Antivaping videos included 15 (50%) videos with the TikTok trend, 10 (33.33%) videos on education, and 5 (16.67%) videos about others. Videos with education have a significantly lower number of likes than other antivaping videos. Most TikTok users posting vaping-related videos are personal accounts (119/203, 58.62%). CONCLUSIONS: Vaping-related TikTok videos are dominated by provaping videos focusing on vaping tricks, advertisement, customization, and TikTok trend. Videos with the TikTok trend have higher user engagement than other video categories. Our findings provide important information on vaping-related videos shared on TikTok and their user engagement levels, which might provide valuable guidance on future policy making, such as possible restrictions on provaping videos posted on TikTok, as well as how to effectively communicate with the public about the potential health risks of vaping.

20.
Acad Radiol ; 30(8): 1628-1637, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36456445

RESUMEN

RATIONALE AND OBJECTIVES: To develop and validate a nomogram for predicting the risk of malignancy of breast imaging reporting and data system (BI-RADS) 4A lesions to reduce unnecessary invasive examinations. MATERIALS AND METHODS: From January 2017 to July 2021, 190 cases of 4A lesions included in this study were divided into training and validation sets in a ratio of 8:2. Radiomics features were extracted from sonograms by Automatic Breast Volume Scanner (ABVS) and B-ultrasound. We constructed the radiomics model and calculated the rad-scores. Univariate and multivariate logistic regressions were used to assess demographics and lesion elastography values (virtual touch tissue image, shear wave velocity) and to develop clinical model. A clinical radiomics model was developed using rad-score and independent clinical factors, and a nomogram was plotted. Nomogram performance was evaluated using discrimination, calibration, and clinical utility. RESULTS: The nomogram included rad-score, age, and elastography, and showed good calibration. In the training set, the area under the receiver operating characteristic curve (AUC) of the clinical radiomics model (0.900, 95% confidence interval (CI): 0.843-0.958) was superior to that of the radiomics model (0.860, 95% CI: 0.799-0.921) and clinical model (0.816, 95% CI: 0.735-0.958) (p = 0.024 and 0.008, respectively). The decision curve analysis showed that the clinical radiomics model had the highest net benefit in most threshold probability ranges. CONCLUSION: ABVS and B-ultrasound-based radiomics nomograms have satisfactory performance in differentiating benign and malignant 4A lesions. This can help clinicians make an accurate diagnosis of 4A lesions and reduce unnecessary biopsy.


Asunto(s)
Neoplasias de la Mama , Diagnóstico por Imagen de Elasticidad , Humanos , Femenino , Nomogramas , Ultrasonografía , Biopsia , Neoplasias de la Mama/diagnóstico por imagen , Estudios Retrospectivos
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