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1.
Eur Radiol ; 34(9): 6072-6081, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38337071

RESUMEN

OBJECTIVES: To study the relationship between the ablation range and applied energy of laser ablation (LA) and microwave ablation (MWA) in papillary thyroid microcarcinoma (PTMC). METHODS: A total of 201 PTMC patients were treated with LA (n = 102) or MWA (n = 99) with single-applicator fixed ablation. The ablation range was determined by contrast-enhanced ultrasound. The ratios of ablation volume, longitudinal diameter, and orthogonal diameter to ablation energy (RAV/E, RAL/E, RAO/E) were analyzed and compared between MWA and LA. The effects of PTMC characteristics and Hashimoto's thyroiditis (HT) on ablation efficiency were evaluated by linear regression. RESULTS: The RAV/E was 0.72 (0.65-0.84) mm3/J for MWA and 0.48 (0.39-0.54) mm3/J for LA. HT was significantly correlated with RAV/E of LA (coefficient = - 0.367, p < 0.0001). RAL/E did not differ significantly between MWA and LA (MWA 0.026 mm/J, LA 0.025 mm/J; p = 0.957). However, MWA had a greater RAO/E than LA (MWA 0.014 mm/J, LA 0.012 mm/J; p < 0.0001). The plateau values of MWA and LA on the ablation orthogonal diameter were 10.7 mm and 8.69 mm, respectively. CONCLUSIONS: MWA showed a higher RAV/E than LA. More intuitively, MWA had a better ablation performance than LA on the orthogonal axis rather than the longitudinal axis. Theoretically, MWA and LA could achieve complete ablation of ≤ 6.70 mm and ≤ 4.69 mm PTMC separately by single-applicator fixed ablation considering a unilateral 2-mm safe margin. HT had a negative effect on LA but not on MWA. CLINICAL RELEVANCE STATEMENT: This study establishes strong connections between ablation energy and ablation range in papillary thyroid microcarcinoma (PTMC) in vivo, possibly contributing to the supplementation of the PTMC Ablation Consensus or Guidelines and providing a scientific basis for choosing clinical ablation parameters in PTMC. KEY POINTS: • Both microwave ablation (MWA) and laser ablation (LA) have excellent performance on the ablation longitudinal axis (easily exceeding 10 mm) for papillary thyroid microcarcinoma (PTMC). • MWA performed much better than LA on the ablation orthogonal axis. • MWA and LA are expected to achieve complete ablation of ≤ 6.70 mm and ≤ 4.69 mm PTMC separately by single-applicator fixed ablation considering a unilateral 2-mm safe margin.


Asunto(s)
Carcinoma Papilar , Terapia por Láser , Microondas , Neoplasias de la Tiroides , Humanos , Femenino , Masculino , Terapia por Láser/métodos , Persona de Mediana Edad , Adulto , Microondas/uso terapéutico , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/diagnóstico por imagen , Carcinoma Papilar/cirugía , Carcinoma Papilar/diagnóstico por imagen , Resultado del Tratamiento , Anciano , Ultrasonografía/métodos , Técnicas de Ablación/métodos , Estudios Retrospectivos , Medios de Contraste
2.
Mol Divers ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38622351

RESUMEN

Alzheimer's disease (AD) and osteoarthritis (OA) are both senile degenerative diseases. Clinical studies have found that OA patients have a significantly increased risk of AD in their later life. This study hypothesized that chronic aseptic inflammation might lead to AD in KOA patients. However, current research has not yet clarified the potential mechanism between AD and KOA. Therefore, this study intends to use KOA transcriptional profiling and single-cell sequencing analysis technology to explore the molecular mechanism of KOA affecting AD development, and screen potential molecular biomarkers and drugs for the prediction, diagnosis, and prognosis of AD in KOA patients. It was found that the higher the expression of TXNIP, MMP3, and MMP13, the higher the risk coefficient of AD was. In addition, the AUC of TXNIP, MMP3, and MMP13 were all greater than 0.70, which had good diagnostic significance for AD. Finally, through the virtual screening of core proteins in FDA drugs and molecular dynamics simulation, it was found that compound Cobicistat could be targeted to TXNIP, Itc could be targeted to MMP3, and Isavuconazonium could be targeted to MMP13. To sum up, TXNIP, MMP3, and MMP13 are prospective molecular markers in KOA with AD, which could be used to predict, diagnose, and prognosis.

3.
Ultraschall Med ; 45(2): 168-175, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37402406

RESUMEN

PURPOSE: To collect validity evidence for a simulator-based obstetric ultrasound competency assessment tool (OUCAT). METHODS: 89 sonographers from three centers (XY, MC, DT), including novices (n=21), experienced trainees (n=44), and experts (n=24), participated in the competency assessment. Validity evidence of OUCAT was collected according to Standards for Educational and Psychological Testing. Content validity was ensured by reviewing guidelines and reaching expert consensus. The response process was ensured via training raters. Internal structure was explored through internal consistency, inter-rater reliability, and test-retest reliability. Relations to other variables were explored by comparing OUCAT scores of sonographers with different experience. Evidence for consequences was collected by determining the pass/fail level. RESULTS: OUCAT included 123 items, of which 117 items could effectively distinguish novices from experts (P<0.05). The internal consistency was represented by the Cronbach's α coefficient (0.978). The inter-rater reliability was high, with XY being 0.868, MC being 0.877, and DT being 0.937 (P<0.001). Test-retest reliability was 0.732 (P=0.001). The performance of experts was significantly better than experienced trainees, and the performance of experienced trainees was significantly better than novices (70.3±10.7 vs. 39.8±15.0 vs. 20.5±10.6, P<0.001). The pass/fail level determined by contrast group method was 45 points. The passing rate of novices, experienced trainees and experts was 0% (0/21), 31.8% (14/44), and 100% (24/24), respectively. CONCLUSION: Simulator-based OUCAT exhibits good reliability and validity in assessing obstetric ultrasound skills.


Asunto(s)
Competencia Clínica , Ultrasonografía Prenatal , Femenino , Embarazo , Humanos , Reproducibilidad de los Resultados , Ultrasonografía , Evaluación Educacional/métodos
4.
Phytochem Anal ; 35(4): 771-785, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38273442

RESUMEN

INTRODUCTION: There are some problems in the quality control of Epimedii Folium (leaves of Epimedium brevicornum Maxim.), such as the mixed use of Epimedii Folium from different harvesting periods and regions, incomplete quality evaluation, and time-consuming analysis methods. OBJECTIVE: Near-infrared (NIR) spectroscopy was conducted to establish a rapid overall quality evaluation method for Epimedii Folium. MATERIALS AND METHODS: Quantitative models of the total solid, moisture, total flavonoid, and flavonol glycoside (Epimedin A, Epimedin B, Epimedin C, Icariin) contents of Epimedii Folium were established by partial least squares regression (PLSR). The root mean square error (RMSE) and correlation coefficient (R) were used to evaluate the performance of models. The qualitative models of Epimedii Folium from different geographic origins and harvest periods were established based on K-nearest neighbor (KNN), back-propagation neural network (BPNN), and random forest (RF). Accuracy and Kappa values were used to evaluate the performance of models. A new multivariable signal conversion strategy was proposed, which combines NIR spectroscopy with the PLSR model to predict the absorbance values of retention time points in the high-performance liquid chromatography (HPLC) fingerprint to obtain the predicted HPLC fingerprint. The Pearson correlation coefficient and cosine coefficient were used to evaluate the similarity between real and predicted HPLC fingerprints. RESULTS: Qualitative models, quantitative models, and the similarity between real and predicted HPLC fingerprints are satisfactory. CONCLUSION: The method serves as a fast and green analytical quality evaluation method of Epimedii Folium and can replace traditional methods to achieve the overall quality evaluation of Epimedii Folium.


Asunto(s)
Quimiometría , Epimedium , Flavonoides , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos , Epimedium/química , Flavonoides/análisis , Análisis de los Mínimos Cuadrados , Quimiometría/métodos , Hojas de la Planta/química , Control de Calidad , Cromatografía Líquida de Alta Presión/métodos
5.
Molecules ; 29(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38792117

RESUMEN

The synergistic effect among flotation agents is why combined flotation agents exhibit superior performance compared to single flotation agents. This research investigates the influence of three surfactants with different charges of polar groups, sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and octanol, combined with dodecylamine (DDA), on quartz flotation. Through the implementation of flotation tests, bubble-particle adhesion induction time testing, gas-liquid two-phase foam properties testing, and surface tension testing, it is revealed that substituting part of the DDA with these surfactants can either enhance or at least maintain the quartz recovery, affect the adhesion induction time, reduce the surface tension of the flotation system, and change the foaming performance and foam stability, depending on their mole ratio in the combined collector. Compared to DDA alone, combining CTAB or OCT with DDA can significantly increase quartz recovery, while SDS with DDA only yields an approximate recovery. Combining SDS or OCT with DDA can reduce the foam stability, while CTAB with DDA enhances the foam stability. The effect of the combination of surfactants and DDA on the adhesion induction time of quartz grains of different sizes with bubbles is the same; furthermore, there is a negative correlation between the adhesion induction time and the recovery, while the foaming properties and stability of foam are positively correlated with the recovery.

6.
Pharm Dev Technol ; 29(3): 265-279, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38416123

RESUMEN

To control hypertension, long-term continuous antihypertensive therapeutics are required and five classes of antihypertensive drugs are frequently involved, including diuretics, ß-blockers, calcium channel blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors. Although with demonstrated clinical utility, there is still room for the improvement of many antihypertensive drugs in oral tablet or capsule dosage form, in terms of reducing systemic side effects and first-pass hepatic drug uptake. Meanwhile, nanocarrier-mediated transdermal drug delivery systems have emerged as a powerful tool for various disease treatments. With benefits such as promoting patient compliance for long-time administration, enhancing skin permeability, and reducing systemic side effects, these systems are reasonably investigated and developed for the transdermal delivery of multiple antihypertensive drugs. This review aims to summarize the literature relating to nanosystem-based transdermal antihypertensive drug delivery and update recent advances in this field, as well as briefly discuss the challenges and prospects of engineering transdermal delivery nanosystems for hypertension treatment.


Asunto(s)
Antihipertensivos , Hipertensión , Humanos , Inhibidores de la Enzima Convertidora de Angiotensina , Hipertensión/tratamiento farmacológico , Bloqueadores de los Canales de Calcio , Administración Cutánea , Antagonistas Adrenérgicos beta/uso terapéutico
7.
Cell Commun Signal ; 21(1): 199, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37563688

RESUMEN

The study was design to investigate the functional roles of Wilms tumor 1-associated protein (WTAP), an enzyme catalyzes m6A modification, in the pathogenesis of osteoarthritis (OA) and further elucidate its possible regulatory mechanism. Herein, we discovered that WTAP was outstandingly upregulated in chondrocyte stimulated with Lipopolysaccharide (LPS) and cartilage tissue of patients with OA. Functional studies have demonstrated that WTAP knockdown enhances proliferation ability, suppresses apoptosis, and reduces extracellular matrix (ECM) degradation in an LPS-induced OA chondrocyte injury model and ameliorates cartilage damage in a destabilizing the medial meniscus (DMM)-induced OA mice model. Conversely, overexpression of WTAP contributes to the opposite effects. Mechanistically, our data has demonstrated that m6A modification mediated by WTAP promotes the maturation of pri-miR-92b to miR-92b-5p, thereby enhancing the targeted inhibitory function of miR-92b-5p on TIMP4. Furthermore, we have discovered that WTAP can directly facilitate the degradation of TIMP4 mRNAs in a YTHDF2-dependent manner. In a nutshell, our findings suggested that WTAP knockdown alleviated OA progression by modulating the miR-92b-5p/TIMP4 axis in an m6A-dependent manner. Our study disclosed that WTAP-mediated m6A modification displayed a crucial role in OA development and suggested that targeting WTAP could be a promising preventive and therapeutic target for patients with OA. Video Abstract.


Asunto(s)
MicroARNs , Osteoartritis , Animales , Ratones , Apoptosis , Condrocitos/metabolismo , Lipopolisacáridos/farmacología , Metiltransferasas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Osteoartritis/metabolismo , Humanos
8.
Int J Hyperthermia ; 39(1): 557-563, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35379066

RESUMEN

AIM: This study aimed to develop a novel tumor-bearing tissue phantom model that can be used for US/CT/MR-guided tumor puncture and thermal ablation. METHODS: The phantom model comprised two parts: a normal tissue-mimicking phantom and a tumor-mimicking phantom. A normal tissue phantom was prepared based on a polyacrylamide gel mixed with thermochromic ink. Moreover, a spherical phantom containing contrast agents was constructed and embedded in the tissue phantom to mimic a tumor lesion. US/CT/MR imaging features and thermochromic property of the phantom model were characterized. Finally, the utility of the phantom model for imaging-guided microwave ablation training was examined. RESULTS: The tumor phantom containing contrast agents showed hyper-echogenicity, higher CT numbers, and lower T2 signal intensity compared with the normal tissue phantom in US/CT/MR images. Consequently, we could locate the position of the tumor in US/CT/MR imaging and perform an imaging-guided tumor puncture. When the temperature reached the threshold of 60 °C, the phantom exhibited a permanent color change from cream white to magenta. Based on this obvious color change, our phantom model could clearly map the thermal ablation region after thermotherapy. CONCLUSIONS: We developed a novel US/CT/MR-imageable tumor-bearing tissue model that can be used for imaging-guided tumor puncture and thermal ablation. Furthermore, it allows visual assessment of the ablation region by analyzing the obvious color change. Overall, this phantom model could be a good training tool in the field of thermal ablation.


Asunto(s)
Hipertermia Inducida , Neoplasias , Humanos , Imagen por Resonancia Magnética/métodos , Neoplasias/diagnóstico por imagen , Neoplasias/cirugía , Punciones , Tomografía Computarizada por Rayos X/métodos
9.
Water Sci Technol ; 86(9): 2336-2347, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36378183

RESUMEN

The inherent periodic structure of montmorillonite limits the adsorption capacity of its endogenous active units such as Si-O tetrahedron and Al-O octahedron for pollutants. The high-intensity ultrasound method was used to release these active units and the layer-by-layer assembly was adopted to prepare carbon@chitosan@montmorillointe microsphere adsorbent (C@CS@Mt) to give full play to the adsorption capacity of montmorillonite. The montmorillonite nanosheet exhibited good hole-making ability, resulting in high surface area, pore volume and pore diameter of microspheres. Benefitting from the release of active sites in Si-O tetrahedron and Al-O octahedron of montmorillonite nanosheets, the adsorption capacity of C@CS@Mt was significantly improved. The maximum adsorption capacities of Pb2+ and methylene blue (MB) reached 884.19 mg·g-1 and 326.21 mg·g-1, respectively. The simultaneous adsorption experiments indicated that the occupation of active sites by Pb2+ caused the observed decrease of MB adsorption capacity. The theoretical calculations indicated that Pb was preferentially adsorbed by active adsorption units due to strong electron donating ability in comparison to MB. As an active unit, Si-O tetrahedron exhibited stronger adsorption capacity for cationic dyes than Al-O octahedron due to both the large electronegativity and lower adsorption binding energy.


Asunto(s)
Azul de Metileno , Contaminantes Químicos del Agua , Azul de Metileno/química , Bentonita , Plomo , Dominio Catalítico , Contaminantes Químicos del Agua/química , Adsorción , Cinética
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(2): 276-284, 2022 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-35523548

RESUMEN

The finite element method is a new method to study the mechanism of brain injury caused by blunt instruments. But it is not easy to be applied because of its technology barrier of time-consuming and strong professionalism. In this study, a rapid and quantitative evaluation method was investigated to analyze the craniocerebral injury induced by blunt sticks based on convolutional neural network and finite element method. The velocity curve of stick struck and the maximum principal strain of brain tissue (cerebrum, corpus callosum, cerebellum and brainstem) from the finite element simulation were used as the input and output parameters of the convolutional neural network The convolutional neural network was trained and optimized by using the 10-fold cross-validation method. The Mean Absolute Error (MAE), Mean Square Error (MSE), and Goodness of Fit ( R 2) of the finally selected convolutional neural network model for the prediction of the maximum principal strain of the cerebrum were 0.084, 0.014, and 0.92, respectively. The predicted results of the maximum principal strain of the corpus callosum were 0.062, 0.007, 0.90, respectively. The predicted results of the maximum principal strain of the cerebellum and brainstem were 0.075, 0.011, and 0.94, respectively. These results show that the research and development of the deep convolutional neural network can quickly and accurately assess the local brain injury caused by the sticks blow, and have important application value for understanding the quantitative evaluation and the brain injury caused by the sticks struck. At the same time, this technology improves the computational efficiency and can provide a basis reference for transforming the current acceleration-based brain injury research into a focus on local brain injury research.


Asunto(s)
Lesiones Encefálicas , Redes Neurales de la Computación , Encéfalo , Simulación por Computador , Análisis de Elementos Finitos , Humanos
11.
Fa Yi Xue Za Zhi ; 38(4): 452-458, 2022 Aug 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-36426687

RESUMEN

OBJECTIVES: To reconstruct the cases of acceleration craniocerebral injury caused by blunt in forensic cases by finite element method (FEM), and to study the biomechanical mechanism and quantitative evaluation method of blunt craniocerebral injury. METHODS: Based on the established and validated finite element head model of Chinese people, the finite element model of common injury tool was established with reference to practical cases in the forensic identification, and the blunt craniocerebral injury cases were reconstructed by simulation software. The cases were evaluated quantitatively by analyzing the biomechanical parameters such as intracranial pressure, von Mises stress and the maximum principal strain of brain tissue. RESULTS: In case 1, when the left temporal parietal was hit with a round wooden stick for the first time, the maximum intracranial pressure was 359 kPa; the maximum von Mises stress of brain tissue was 3.03 kPa at the left temporal parietal; the maximum principal strain of brain tissue was 0.016 at the left temporal parietal. When the right temporal was hit with a square wooden stick for the second time, the maximum intracranial pressure was 890 kPa; the maximum von Mises stress of brain tissue was 14.79 kPa at the bottom of right temporal lobe; the maximum principal strain of brain tissue was 0.103 at the bottom of the right temporal lobe. The linear fractures occurred at the right temporal parietal skull and the right middle cranial fossa. In case 2, when the forehead and left temporal parietal were hit with a round wooden stick, the maximum intracranial pressure was 370 kPa and 1 241 kPa respectively, the maximum von Mises stress of brain tissue was 3.66 kPa and 26.73 kPa respectively at the frontal lobe and left temporal parietal lobe, and the maximum principal strain of brain tissue was 0.021 and 0.116 respectively at the frontal lobe and left temporal parietal lobe. The linear fracture occurred at the left posterior skull of the coronary suture. The damage evaluation indicators of the simulation results of the two cases exceeded their damage threshold, and the predicted craniocerebral injury sites and fractures were basically consistent with the results of the autopsy. CONCLUSIONS: The FEM can quantitatively evaluate the degree of blunt craniocerebral injury. The FEM combined with traditional method will become a powerful tool in forensic craniocerebral injury identification and will also become an effective means to realize the visualization of forensic evidence in court.


Asunto(s)
Traumatismos Craneocerebrales , Heridas no Penetrantes , Humanos , Análisis de Elementos Finitos , Fenómenos Biomecánicos , Cabeza
12.
J Am Chem Soc ; 143(36): 14530-14539, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34464109

RESUMEN

Atomically dispersed M-N-C (M refers to transition metals) materials represent the most promising catalyst alternatives to the precious metal Pt for the electrochemical reduction of oxygen (ORR), yet the genuine active sites in M-N-C remain elusive. Here, we develop a two-step approach to fabricate Cu-N-C single-atom catalysts with a uniform and well-defined Cu2+-N4 structure that exhibits comparable activity and superior durability in comparison to Pt/C. By combining operando X-ray absorption spectroscopy with theoretical calculations, we unambiguously identify the dynamic evolution of Cu-N4 to Cu-N3 and further to HO-Cu-N2 under ORR working conditions, which concurrently occurs with reduction of Cu2+ to Cu+ and is driven by the applied potential. The increase in the Cu+/Cu2+ ratio with the reduced potential indicates that the low-coordinated Cu+-N3 is the real active site, which is further supported by DFT calculations showing the lower free energy in each elemental step of the ORR on Cu+-N3 than on Cu2+-N4. These findings provide a new understanding of the dynamic electrochemistry on M-N-C catalysts and may guide the design of more efficient low-cost catalysts.

13.
Angew Chem Int Ed Engl ; 59(4): 1659-1665, 2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-31639242

RESUMEN

The development of high-efficiency electrocatalysts for large-scale water splitting is critical but also challenging. In this study, a hierarchical CoMoSx chalcogel was synthesized on a nickel foam (NF) through an in situ metathesis reaction and demonstrated excellent activity and stability in the electrocatalytic hydrogen evolution reaction and oxygen evolution reaction in alkaline media. The high catalytic activity could be ascribed to the abundant active sites/defects in the amorphous framework and promotion of activity through cobalt doping. Furthermore, the superhydrophilicity and superaerophobicity of micro-/nanostructured CoMoSx /NF promoted mass transfer by facilitating access of electrolytes and ensuring fast release of gas bubbles. By employing CoMoSx /NF as bifunctional electrocatalysts, the overall water splitting device delivered a current density of 500 mA cm-2 at a low voltage of 1.89 V and maintained its activity without decay for 100 h.

14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(6): 649-656, 2019 Jun 28.
Artículo en Zh | MEDLINE | ID: mdl-31304926

RESUMEN

OBJECTIVE: To compare the clinical value of superb microvascular imaging (SMI) and contrast enhanced ultrasound (CEUS) in the differential diagnosis of thyroid nodules, and to further study whether the combination of SMI and/or CEUS with thyroid imaging reporting and data system (TI-RADS) can improve the diagnostic value of TI-RADS.
 Methods: SMI, CEUS, TI-RADS, TI-RADS combined with CEUS, TI-RADS combined with SMI, TI-RADS combined with SMI and CEUS were used to differentiate thyroid nodules. TI-RADS 4b, 5 categories in two-dimensional ultrasound, hypoenhancement in CEUS, and peripheral blood flow with penetrating vessels in SMI were considered malignant signs. The diagnostic efficacy of these methods was compared according to post-operative pathology or fine needle aspiration cytology.
 Results: A total of 237 patients with 296 thyroid nodules were included in the study. The sensitivity, specificity and accuracy for TI-RADS were 78.4%, 77.7% and 78.0% respectively, 75.5%, 86.6% and 81.4% in SMI, 82.0%, 88.5% and 85.5% in CEUS, 92.1%, 90.4% and 91.2% in TI-RADS combined with SMI and CEUS. Area under the receiver operating characteristic curve (AUROC) showed no significant difference between SMI, CEUS, TI-RADS (χ2=4.29, P=0.117). AUROC of both TI-RADS combined with CEUS (χ2=39.62, P<0.001), TI-RADS combined with SMI (χ2=36.61, P<0.001) were higher than TI-RADS. AUROC of TI-RADS combined with SMI and CEUS was higher than TI-RADS combined with SMI (χ2=4.50, P=0.033) or TI-RADS combined with CEUS (χ2=4.24, P=0.039).
 Conclusion: Peripheral blood flow with penetrating vessels in SMI possesses high diagnostic value in differentiating thyroid cancer. The combination of SMI and/or CEUS with TI-RADS can be used to improve the diagnostic efficacy of TI-RADS in differential diagnosis of thyroid nodules.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Diagnóstico Diferencial , Humanos , Ultrasonografía
15.
J Ultrasound Med ; 37(2): 425-437, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28880412

RESUMEN

OBJECTIVES: We aimed to determine the most efficient quantitative parameters to establish a contrast-enhanced ultrasound (US) assessment system for distinguishing between benign and malignant thyroid nodules. METHODS: A total of 167 patients with thyroid solitary nodules had the diagnosis confirmed by surgery or fine-needle aspiration. Quantitative contrast-enhanced US indicators (time to peak, time from peak to one-half, ascend slope, descend slope, peak intensity, and area under the curve [AUC]) were gathered in nodule and perinodule areas. Univariate and multivariate logistic regression analyses were performed. Receiver operating characteristic curves were generated. Sensitivities, specificities, and positive and negative predictive values were calculated to identify the best cutoff value. RESULTS: The univariate logistic regression model showed that the peak intensity, ascend slope, descend slope, and AUC were significant indicators for discriminating benign from malignant nodules under contrast-enhanced US (P < .0001). For thyroid nodules, low peak intensity, ascend slope, and AUC and high descend slope values were significant indicators of malignancy. However, in perinodule areas, high peak intensity, ascend slope, and AUC and low descend slope values were significantly associated with malignancies. The cutoff values for the nodule peak intensity, ascend slope, descend slope, and AUC were 20.75, 0.91, -0.2, and 1818.23, respectively. The cutoff values for the ratios of the nodule versus perinodule peak intensity, ascend slope, descend slope, and AUC were 0.90, 0.95, 0.96, and 0.96. The nodule-to-perinodule peak intensity ratio showed the best diagnostic efficiency, with 80.41% sensitivity and 80.00% specificity. CONCLUSIONS: Quantitative contrast-enhanced US indicators help discriminate benign from malignant thyroid nodules. The nodule-to-perinodule peak intensity ratio showed the best diagnostic efficiency.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Neoplasias de la Tiroides/diagnóstico por imagen , Nódulo Tiroideo/diagnóstico por imagen , Ultrasonografía/métodos , Adulto , Diagnóstico Diferencial , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Glándula Tiroides/diagnóstico por imagen
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 43(1): 35-40, 2018 Jan 28.
Artículo en Zh | MEDLINE | ID: mdl-30154289

RESUMEN

OBJECTIVE: To examine the role of LY294002 in cardiac function and myocardial structure in dilated cardiomyopathy (DCM) rats.
 Methods: Fifty-two male SD rats were randomly assigned to a control group (n=16) and a DCM group (n=36). The DCM rats were induced by intraperitoneal injection of adriamycin, and the control rats were given normal saline. After observation for 2 weeks, 6 rats from each group were killed randomly. In the end of the 8th week, the 24 DCM rats were randomly assigned to a DCM group (n=12) and a LY294002 group (n=12), which were given normal saline and LY294002, respectively. In the end of the 8th week and 16th week, the cardiac function was analyzed by ultrasonic cardiogram (UCG) and the plasma was collected to test the level of N-terminal pro-brain natriuretic peptide (NT-pro BNP). HE and Van Gieson (VG) staining were performed to calculate the collagen volume fraction (CVF).
 Results: Compared with the control group, the left ventricular end-diastolic dimension (LVEDD), left ventricular end-systolic dimension (LVESD) and NT-proBNP level of in the DCM rats were increased obviously, while the left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS) in the DCM rats were decreased obviously (P<0.01). These changes were consistent with DCM characteristics. Compared with the DCM group, the LVEDD, LVESD and NT-proBNP levels in the LY294002 group were decreased, while the LVEF and LVFS were increased (P<0.05). Histopathology showed that the myocardium in the DCM rats was fibrotic and the CVF was increased compared with the control rats (P<0.01). The myocardial structure was improved in the LY294002 group compared to the DCM group.
 Conclusion: LY294002 can reduce the myocardial fibrosis in the DCM rats and improve the cardiac function.


Asunto(s)
Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/fisiopatología , Miocardio/patología , Animales , Factor Natriurético Atrial/sangre , Cardiomiopatías , Cardiomiopatía Dilatada/sangre , Cardiomiopatía Dilatada/patología , Colágeno/análisis , Fibrosis , Corazón/efectos de los fármacos , Masculino , Precursores de Proteínas/sangre , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Función Ventricular Izquierda/fisiología
17.
Angew Chem Int Ed Engl ; 57(24): 7071-7075, 2018 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-29683255

RESUMEN

Hydrothermally stable, acid-resistant nickel catalysts are highly desired in hydrogenation reactions, but such a catalyst remains absent owing to the inherent vulnerability of nickel under acidic conditions. An ultra-durable Ni-N-C single-atom catalyst (SAC) has now been developed that possesses a remarkable Ni content (7.5 wt %) required for practical usage. This SAC shows not only high activities for hydrogenation of various unsaturated substrates but also unprecedented durability for the one-pot conversion of cellulose under very harsh conditions (245 °C, 60 bar H2 , presence of tungstic acid in hot water). Using integrated spectroscopy characterization and computational modeling, the active site structure is identified as (Ni-N4)⋅⋅⋅N, where significantly distorted octahedral coordination and pyridinic N constitute a frustrated Lewis pair for the heterolytic dissociation of dihydrogen, and the robust covalent chemical bonding between Ni and N atoms accounts for its ultrastability.

18.
J Am Chem Soc ; 139(31): 10790-10798, 2017 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-28745500

RESUMEN

Nanostructured Fe-N-C materials represent a new type of "platinum-like" non-noble-metal catalyst for various electrochemical reactions and organic transformations. However, no consensus has been reached on the active sites of the Fe-N-C catalysts because of their heterogeneity in particle size and composition. In this contribution, we have successfully prepared atomically dispersed Fe-N-C catalyst, which exhibited high activity and excellent reusability for the selective oxidation of the C-H bond. A wide scope of substrates, including aromatic, heterocyclic, and aliphatic alkanes, were smoothly oxidized at room temperature, and the selectivity of corresponding products reached as high as 99%. By using sub-ångström-resolution HAADF-STEM in combination with XPS, XAS, ESR, and Mössbauer spectroscopy, we have provided solid evidence that Fe is exclusively dispersed as single atoms via forming FeNx (x = 4-6) and that the relative concentration of each FeNx species is critically dependent on the pyrolysis temperature. Among them, the medium-spin FeIIIN5 affords the highest turnover frequency (6455 h-1), which is at least 1 order of magnitude more active than the high-spin and low-spin FeIIIN6 structures and 3 times more active than the FeIIN4 structure, although its relative concentration in the catalysts is much lower than that of the FeIIIN6 structures.

19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 41(7): 736-40, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-27592580

RESUMEN

OBJECTIVE: To analyze the characteristics of left ventricular rotation and twist in patients with silent myocardial ischemia (SMI) by three-dimensional speckle tracking echocardiography (3D-STE), and to explore the diagnostic value of this method for SMI.
 METHODS: According to Gensini score, 66 patients with SMI were divided into 3 subgroups: a mild lesion group (n=16), a moderate lesion group (n=26) and a severe lesion group (n=24). Thirty patients with negative results in selective coronary angiography served as a control group. The parameters of wall motion score index (WMSI), left ventricular ejection fraction (LVEF), peak basal rotation (Ptw-B), peak apical rotation (Prot-A), left ventricular peak apical rotation (LVrot), left ventricular peak apical twist (LVtw) were measured.
 RESULTS: In the SMI group, with an increase in severity of myocardial ischemia, LVEF, Prot-A, Prot-B, LVrot, LVtw showed a decrease trend while WMSI exhibited an opposite phenomenon (P<0.05), and all of them displayed a significant corelation with Gensini score (P<0.05). In the diagnosis of SMI, all of the above-mentioned parameters were highly sensitive and specific. 3D-STE showed the highest diagnostic value for LVtw.
 CONCLUSION: Left ventricular rotation and twisting motion monitered by 3D-STE can evaluate the severity of myocardial ischemia in patients with SMI.


Asunto(s)
Isquemia Miocárdica , Enfermedad de la Arteria Coronaria , Ecocardiografía Tridimensional , Ventrículos Cardíacos , Humanos , Rotación , Función Ventricular Izquierda
20.
Echocardiography ; 31(1): 58-66, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23953025

RESUMEN

PURPOSE: To compare parameters between three-dimensional speckle tracking echocardiography (3DSTE) and delayed enhancement magnetic resonance imaging (DE-MRI) for estimating myocardial infarct size, peak systolic strain, and transmural involvement of infarct segments in patients with acute myocardial infarction (AMI). METHODS: Delayed enhancement MRI was conducted to determine myocardial infarction (MI) position, size, and transmural involvement in 26 patients with AMI. 3DSTE was conducted to measure global peak systolic strain in the left ventricle and to estimate longitudinal, circumferential, and radial peak systolic strain in papillary muscle segments. Conventional echocardiography was used to calculate the wall-motion score index (WMSI) and left ventricular ejection fraction (LVEF). RESULTS: Left ventricular strain parameters and LVEF were statistically significantly lower in patients with large-size MI than in those with small-size MI. Global longitudinal strain (GLS) and global circumferential strain (GCS) were significantly lower in patients with moderate-size MIs than in those with small-size MIs. All parameters except ejection fraction (EF) were lower in patients with large-size MI compared with those with moderate-size MI (P < 0.05). Pearson analysis revealed that left ventricular GCS, GLS, GRS, WMSI, and LVEF of AMI patients correlated with the myocardial infarct area (MIA) measured by MRI (r = 0.86, 0.81, -0.71, 0.64, and -0.66, respectively; all P-values <0.01). Transmural infarct segments exhibited significantly lower longitudinal, circumferential, and radial strains than normal segments (P < 0.05). CONCLUSIONS: These findings indicate that 3DSTE can distinguish between MIs of different infarct sizes, and may provide an indirect means for the accurate determination of transmural involvement in infarct segments.


Asunto(s)
Ecocardiografía Tridimensional/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Anciano , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
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