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1.
Proc Natl Acad Sci U S A ; 117(27): 15409-15413, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32571928

RESUMEN

The resistance of a conventional insulator diverges as temperature approaches zero. The peculiar low-temperature resistivity saturation in the 4f Kondo insulator (KI) SmB6 has spurred proposals of a correlation-driven topological Kondo insulator (TKI) with exotic ground states. However, the scarcity of model TKI material families leaves difficulties in disentangling key ingredients from irrelevant details. Here we use angle-resolved photoemission spectroscopy (ARPES) to study FeSb2, a correlated d-electron KI candidate that also exhibits a low-temperature resistivity saturation. On the (010) surface, we find a rich assemblage of metallic states with two-dimensional dispersion. Measurements of the bulk band structure reveal band renormalization, a large temperature-dependent band shift, and flat spectral features along certain high-symmetry directions, providing spectroscopic evidence for strong correlations. Our observations suggest that exotic insulating states resembling those in SmB6 and YbB12 may also exist in systems with d instead of f electrons.

2.
Proc Natl Acad Sci U S A ; 116(29): 14511-14515, 2019 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-31266887

RESUMEN

Quantum-relativistic materials often host electronic phenomena with exotic spatial distributions. In particular, quantum anomalous Hall (QAH) insulators feature topological boundary currents whose chirality is determined by the magnetization orientation. However, understanding the microscopic nature of edge vs. bulk currents has remained a challenge due to the emergence of multidomain states at the phase transitions. Here we use microwave impedance microscopy (MIM) to directly image chiral edge currents and phase transitions in a magnetic topological insulator. Our images reveal a dramatic change in the edge state structure and an unexpected microwave response at the topological phase transition between the Chern number [Formula: see text] and [Formula: see text] states, consistent with the emergence of an insulating [Formula: see text] state. The magnetic transition width is independent of film thickness, but the transition pattern is distinct in differently initiated field sweeps. This behavior suggests that the [Formula: see text] state has 2 surface states with Hall conductivities of [Formula: see text] but with opposite signs.

3.
Appl Opt ; 55(8): 1957-65, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26974789

RESUMEN

The current waveform model of a laser altimeter is based on the Gaussian laser beam of the fundamental mode, whose cross section is a circular spot, whereas some of the cross sections of Geoscience Laser Altimeter System lasers are closer to elliptical spots. Based on the expression of the elliptical Gaussian beam and the waveform theory of laser altimeters, the primary parameters of an echo waveform were derived. In order to examine the deduced expressions, a laser altimetry waveform simulator and waveform processing software were programmed and improved under the circumstance of an elliptical Gaussian beam. The result shows that all the biases between the theoretical and simulated waveforms were less than 0.5%, and the derived model of an elliptical spot is universal and can also be used for the conventional circular spot. The shape of the waveforms is influenced by the ellipticity of the laser spot, the target slope, and the "azimuth angle" between the major axis and the slope direction. This article provides the waveform theoretical basis of a laser altimeter under an elliptical Gaussian beam.

4.
Int J Cardiol ; 399: 131775, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38211676

RESUMEN

OBJECTIVE: To explore the safety and assess the cardiovascular impact of early in-hospital administration of PCSK9 inhibitors in patients with acute coronary syndrome (ACS). METHODS: A systematic search of PubMed, Web of Science, and Embase databases was conducted for studies involving the use of PCSK9 inhibitors in ACS patients from inception to October 2023. Two independent researchers screened the literature, extracted data, and assessed the risk of bias in the included studies. Meta-analysis was performed using STATA 16.0 software. RESULTS: Nine studies, encompassing a total of 2896 ACS patients, were included in the analysis. When compared to statin monotherapy, early administration of PCSK9 inhibitors during hospitalization for ACS proved effective in reducing the incidence of major adverse cardiovascular events (MACEs). This encompassed a decrease in coronary revascularization [Relative Risk (RR) = 0.78, 95% CI (0.62, 0.98), P < 0.05], recurrent ACS [RR = 0.62, 95% CI (0.42, 0.94), P < 0.05], readmissions due to unstable angina [RR = 0.71, 95% CI (0.59, 0.85), P < 0.01], and strokes [RR = 0.31, 95% CI (0.09, 1.04), P = 0.058]. There was no significant difference in the incidence of death between the two groups.The use of PCSK9 inhibitors notably hastened the reduction of LDL-C, TG, and Non HDL-C levels in the short term. Additionally, it increased HDL-C levels and the number of individuals meeting LDL-C compliance criteria. Importantly, the risk of adverse drug events, such as ALT increase >3xULN, allergies, and musculoskeletal pain, did not significantly elevate with PCSK9 inhibitor use. CONCLUSION: The early administration of PCSK9 inhibitors has been found to safely and effectively lower diverse lipid levels in patients with ACS. This reduction is associated with a noteworthy decrease in MACEs, encompassing revascularization, recurrent ACS, and hospital readmissions.


Asunto(s)
Síndrome Coronario Agudo , Anticolesterolemiantes , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Humanos , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/inducido químicamente , Inhibidores de PCSK9 , Proproteína Convertasa 9 , LDL-Colesterol , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hospitales , Anticolesterolemiantes/uso terapéutico
5.
Heart Lung ; 67: 158-168, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38788303

RESUMEN

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a preferred treatment for patients with highly critical aortic stenosis (AS), which is a difficult and complicated procedure, leaving a heavy economical burden on patients and national health insurance. Minimalist TAVR can simplify a part of the operation procedures, but the surgical efficacy and safety are still under debated. OBJECTIVES: Explore the effectiveness and safety of minimalist TAVR in the treatment of patients with aortic stenosis. METHODS: A systematic search of PubMed, Web of Science, and Embase databases was conducted for studies involving application of minimalist TAVR in patients with severe aortic stenosis, two researchers independently screened the literature, extracted data and Meta-analysis was performed using STATA 16.0 software. RESULTS: Nine studies, involving a total of 3,148 AS patients, were included. Minimalist TAVR has similar surgical success rates compared to standardized TAVR, intraoperative fluoroscopy time, dosage of contrast agent, and total operative time were superior to standard TAVR. Regarding surgical complications, the incidence of permanent pacemaker placement and moderate to severe paravalvular leakage were similar for both TAVR, the risk of major vascular complications and major bleeding events in the minimalist TAVR was significantly lower than the standard TAVR. The risk of overall death, stroke, and cardiovascular-related readmission within 30 days was similar in both procedures. CONCLUSION: Patients with severe aortic stenosis treated with minimalist TAVR have similar short-term efficacy as well as 30-day clinical outcomes to standard TAVR, while minimalist TAVR could reduce the risk of major vascular complications and bleeding complications.


Asunto(s)
Estenosis de la Válvula Aórtica , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Estenosis de la Válvula Aórtica/cirugía , Complicaciones Posoperatorias/epidemiología , Resultado del Tratamiento , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos
6.
Psychiatry Res Neuroimaging ; 339: 111787, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38295529

RESUMEN

BACKGROUND: Transcutaneous electrical cranial-auricular acupoint stimulation (TECAS) is a novel non-invasive therapy for major depressive disorder (MDD) that stimulates acupoints innervated by the trigeminal and auricular vagus nerves. However, there are few neuroimaging studies involving the TECAS for the treatment of MDD. Therefore, this study aimed to investigate the treatment response and neurological effects of TECAS using resting-state functional magnetic resonance imaging (rs-fMRI). METHOD: A total of 34 patients with mild-to-moderate MDD and 34 demographically matched healthy controls (HCs) were recruited. After an eight-week treatment the primary outcome was clinical response, defined as a baseline-to-endpoint ≥ 50 % reduction in the 17-item Hamilton Depression Rating Scale (HAMD-17). The low-frequency fluctuations (ALFF) method were used to investigate the brain abnormalities of MDD patients and HCs, and altered brain networks were analyzed between pre- and post-treatment using seed-based functional connectivity (FC) analysis. RESULTS: We found no significant differences in terms of gender, age, and years of education between the two groups. After treatment, the response rate was 58.82 %. Compared to HCs, MDD patients showed lower ALFF values in the left insula(t = -4.298,P < 0.005), the insula-based FC revealed in the right middle frontal gyrus (MFG)/ right superior frontal gyrus, orbital part (ORBsupmed) (t = -5.29,P < 0.005) and the right anterior cingulate gyrus (ACC)were decreased (t = -6.08,P < 0.005). Furthermore, Compared to pre-treatment, abnormal FC values in the ACC /orbital superior frontal gyrus (SFG) (t = 3.42,P < 0.005) and left superior frontal gyrus (SFG)/ supplement motor area (SMA) were enhanced (t = 3.34,P < 0.005). CONCLUSION: TECAS exhibits antidepressant efficacy, particularly influencing the insula-based functional connections within the Default Mode Network (DMN) related to emotion processing in individuals with MDD.


Asunto(s)
Trastorno Depresivo Mayor , Humanos , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/tratamiento farmacológico , Puntos de Acupuntura , Red en Modo Predeterminado , Encéfalo/diagnóstico por imagen , Antidepresivos
7.
Front Endocrinol (Lausanne) ; 12: 631097, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33737911

RESUMEN

Background: Subchorionic hematoma (SCH) is common in early pregnancy achieved by in vitro fertilization-embryo transfer/frozen embryo transfer (IVF-ET/FET), and is associated with adverse obstetric outcomes. However, there are no methods known to accurately predict the occurrence of SCH. Objective: To establish a nomogram prediction model for predicting the risk of SCH in early pregnancy with IVF-ET/FET and to analyze pregnancy outcomes of patients with SCH. Methods: Patients who underwent IVF-ET/FET treatment and were diagnosed with clinical pregnancy were enrolled in our study. A total of 256 patients with SCH were enrolled in the SCH group, and 526 patients without SCH in the control group. Logistic regression was used to screen risk factors for SCH, and the nomogram was developed according to the regression coefficient of relevant variables. Discrimination, effect, calibration, and the predictive model's clinical usefulness were assessed using the C-index, the area under the receiver operating characteristic standard curve, calibration plot, and decision curve analysis. Internal validation was assessed using bootstrapping validation. The effects of SCH on pregnancy outcomes were analyzed. Results: A multivariate logistic regression analysis showed that fresh embryo transfer, polycystic ovary syndrome, hydrosalpinx, and thin endometrium were risk factors affecting the occurrence of SCH. Based on the above factors, a predictive model for the risk of SCH was created. The model displayed good discrimination, with a C-index of 0.783 (95% confidence interval: 0.750-0.816), area under the receiver operating characteristic standard curve of 0.783, and good calibration. A high C-index value of 0.765 could still be reached in the interval validation. Decision curve analysis showed that the nomogram was clinically useful when the intervention was decided at the SCH possibility threshold of 4%-87%. For patients with successful deliveries, the occurrence of SCH did not influence the gestational weeks of delivery, mode of delivery, preterm birth, height, and weight of the newborn. Conclusion: We screened the risk factors for SCH in patients who underwent IVF-ET/FET treatment. Successful establishment of a nomogram can effectively predict the occurrence of SCH. Furthermore, the incidence of miscarriage is higher in patients with SCH.


Asunto(s)
Transferencia de Embrión/métodos , Fertilización In Vitro/métodos , Hematoma/diagnóstico , Adulto , Área Bajo la Curva , Calibración , Criopreservación , Toma de Decisiones , Reacciones Falso Positivas , Femenino , Humanos , Análisis Multivariante , Nomogramas , Valor Predictivo de las Pruebas , Embarazo , Resultado del Embarazo , Probabilidad , Análisis de Regresión , Reproducibilidad de los Resultados , Riesgo , Factores de Riesgo
8.
J Immunoassay Immunochem ; 29(2): 161-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18360811

RESUMEN

Antinuclear antibodies, ANA, were usually detected with antigen of somatic cell nucleus. It has not been reported to detect ANA with egg cell nucleus as antigen. Enzyme linked immuosorbent assay, ELISA, coated with yolk was developed to detect ANA in our laboratory. A quality control test, cross absorption test, and cross antibody-induced test with yolk were performed. Results showed a good agreement between our method and IFA through measurement of the same samples from patients suspected of having rheumatic connective tissue diseases (Kappa=0.668, P=0.000). The results were not influenced by the RF and different sources of egg. CVs of inter-assay, were less than 10%. The cross absorption test was negative, as well; the ANA to somatic cell nucleus could be induced with egg cell nucleus. It is implied that there were both cross as well as overlapped Egg-ANA and Somatic-ANA. As egg nucleus, its volume was large, its purification was simple, so the better method might be established.


Asunto(s)
Anticuerpos Antinucleares/inmunología , Núcleo Celular/química , Óvulo/química , Enfermedades Reumáticas/inmunología , Animales , Anticuerpos Antinucleares/sangre , Núcleo Celular/inmunología , Reacciones Cruzadas , Proteínas del Huevo/química , Proteínas del Huevo/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Ratones , Óvulo/inmunología , Enfermedades Reumáticas/sangre , Sensibilidad y Especificidad , Saco Vitelino/química , Saco Vitelino/inmunología
9.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 36(1): 23-28, 2018 Feb 01.
Artículo en Zh | MEDLINE | ID: mdl-29594991

RESUMEN

OBJECTIVE: This study aims to investigate the effect of neurotrophin 3 (NT-3) on the osteogenic differentiation of human dental follicle cells (hDFCs). METHODS: hDFCs were isolated and cultured in vitro. Immunocytochemical staining was used to identify the origin of hDFCs. The effects of different NT-3 concentrations on hDFCs proliferation were detected by using CCK-8 assay. The alkaline phosphatase (ALP) activities and mRNA expression levels of bone morphogenetic protein-2 (BMP-2) and osteocalcin (OCN) were determined to investigate the effects of NT-3 on hDFCs osteogenesis. The difference in the number of mineralized nodules was detected using alizarin red staining. RESULTS: Vimentin and cytokeratin staining results showed that hDFCs originated from the mesenchymal cells. NT-3 exerted no evident effect on hDFCs proliferation. The ALP activity and the BMP-2 and OCN mRNA expression levels of hDFCs were significantly improved under treatment with different NT-3 concentrations (25, 50, and 100 ng·mL ⁻¹) compared with those in the control group. BMP-2 and OCN mRNA relative expression levels of hDFCs reached the highest when the NT-3 concentration was 100 ng·mL ⁻¹. The number of mineralized nodules reached the maximum when the hDFCs were treated with 50 and 100 ng·mL ⁻¹ NT-3. CONCLUSIONS: Appropriate mass concentration of NT-3 can promote the osteogenic differentiation of hDFCs.


Asunto(s)
Diferenciación Celular , Saco Dental , Células Madre Mesenquimatosas , Neurotrofina 3 , Osteogénesis , Fosfatasa Alcalina , Proteína Morfogenética Ósea 2/metabolismo , Células Cultivadas , Humanos , Neurotrofina 3/farmacología , Osteocalcina/metabolismo
10.
Head Neck ; 39(5): 1008-1014, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28252829

RESUMEN

BACKGROUND: The mainstay of treatment in adenoid cystic carcinoma (ACC) of the head and neck is surgical resection with negative margins. The purpose of this study was to define the margin status that associates with survival outcomes of ACC of the head and neck. METHODS: We conducted univariate and multivariate analyses of international data. RESULTS: Data of 507 patients with ACC of the head and neck were analyzed; negative margins defined as ≥5 mm were detected in 253 patients (50%). On multivariate analysis, the hazard ratios (HRs) of positive margin status were 2.68 (95% confidence interval [CI], 1.2-6.2; p = .04) and 2.63 (95% CI, 1.1-6.3; p = .03) for overall survival (OS) and disease-specific survival (DSS), respectively. Close margins had no significant impact on outcome, with HRs of 1.1 (95% CI, 0.4-3.0; p = .12) and 1.07 (95% CI, 0.3-3.4; p = .23) for OS and DSS, respectively, relative with negative margins. CONCLUSION: In head and neck ACC, positive margins are associated with the worst outcome. Negative or close margins are associated with improved outcome, regardless of the distance from the tumor. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1008-1014, 2017.


Asunto(s)
Carcinoma Adenoide Quístico/patología , Carcinoma Adenoide Quístico/cirugía , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/cirugía , Márgenes de Escisión , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Adenoide Quístico/mortalidad , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 34(5): 468-473, 2016 Oct 01.
Artículo en Zh | MEDLINE | ID: mdl-28326703

RESUMEN

OBJECTIVE: This study investigated the effects of salvianolic acid B (Sal B), a major bioactive component of the Chinese medicine salvia miltiorrhiza, on osteogenic differentiation of human periodontal ligament cells (hPDLCs). METHODS: Third passage PDLCs were used in this experiment. Methyl thiazolyl tetrazolium (MTT) method was employed to observe the effects of different Sal B concentrations on proliferation activity of hPDLCs. Alkaline phosphatase (ALP) activity and mineralization capability were measured, and mRNA expression of osteocalcin (OCN) was detected to investigate the effects of Sal B on osteogenesis of hPDLCs. RESULTS: Sal B did not influence the viability of hPDLCs. The ALP activity and OCN mRNA expression levels of hPDLCs were both significantly improved (P<0.05) under treatment with different Sal B concentrations (0.5, 1, and 5 µmol·L⁻¹) compared with those in OIM group. Moreover, the number of mineralized nodules formed by hPDLCs were considerably higher under treatment with different Sal B concentrations (0.5, 1, and 5 µmol·L⁻¹) than that in the OIM group. CONCLUSIONS: Appropriate Sal B concentration can improve the osteogenic differentiation of hPDLCs.


Asunto(s)
Diferenciación Celular , Osteogénesis , Ligamento Periodontal , Benzofuranos , Células Cultivadas , Humanos , Osteocalcina
12.
J Food Sci ; 75(6): C493-7, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20722902

RESUMEN

The effect of the beeswax, Span 20, and glycerol content on qualities of soybean-protein-isolate edible films was evaluated. Beeswax and Span 20 were selected to improve qualities of soybean-protein-isolate films from 11 emulsifiers. The content of beeswax, Span 20, and glycerol was further optimized by response surface analysis. The optimal composite emulsifier was beeswax (1.87% of soybean protein-isolate), Span 20 (10.25% of soybean protein-isolate), and glycerol (29.12% of soybean protein-isolate) with tensile strength of 908 MPa, percentage elongation at break of 25.8%, water vapor permeability of 19.2 g/m.d.MPa, and oxygen permeability of 0 cm(3)/m.d.MPa. The quality of soybean-protein-isolate films incorporated with the optimal composite emulsifier was 2.34 times higher than that of the control. Furthermore, the disulfide bond content of soybean-protein-isolate films showed a positive correlation with their quality, which provided a simple and rapid way to rank quality of soybean-protein-isolate films. Therefore, our result will not only give an instruction to soybean-protein-isolate-film production, but also give a simple and rapid way to rank film qualities. Practical Application: Our results give the optimal composite emulsifiers for the soybean-protein-isolate-film production. The soybean-protein-isolate films based on the optimal composite emulsifiers show their tensile strength of 908 MPa, percentage elongation at break of 25.8%, water vapor permeability of 19.2 g/m.d.MPa, and oxygen permeability of 0 cm(3)/m.d.MPa, being stronger than the control. Moreover, our results give a simple and rapid way to rank film qualities, because the disulfide bond content of soybean-protein-isolate films showed a positive correlation with their quality. Hence, the disulfide bond content was an indicator to rank qualities of soybean-protein-isolate films.


Asunto(s)
Glicerol/química , Hexosas/química , Proteínas de Soja/química , Ceras/química , Disulfuros/análisis , Elasticidad , Emulsionantes/química , Embalaje de Alimentos/instrumentación , Industria de Procesamiento de Alimentos/métodos , Modelos Estadísticos , Oxígeno , Permeabilidad , Control de Calidad , Vapor , Compuestos de Sulfhidrilo/análisis , Propiedades de Superficie , Resistencia a la Tracción
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