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1.
Nano Lett ; 23(22): 10490-10497, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37909686

RESUMEN

The energy transfer (ET) between organic molecules and semiconductors is a crucial mechanism for enhancing the performance of semiconductor-based optoelectronic devices, but it remains undiscovered. Here, ultrafast optical pump-probe spectroscopy was utilized to directly reveal the ET between organic Alq3 molecules and Si semiconductors. Ultrathin SiO2 dielectric layers with a thickness of 3.2-10.8 nm were inserted between Alq3 and Si to prevent charge transfer. By means of the ET from Alq3 to Si, the SiO2 thickness-dependent relaxation dynamics of photoexcited carriers in Si have been unambiguously observed on the transient reflectivity change (ΔR/R) spectra, especially for the relaxation process on a time scale of 200-350 ps. In addition, these findings also agree with the results of our calculation in a model of long-range dipole-dipole interactions, which provides critical information for developing future optoelectronic devices.

2.
Adv Sci (Weinh) ; 10(17): e2300845, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37132589

RESUMEN

Plumbene, with a structure similar to graphene, is expected to possess a strong spin-orbit coupling and thus enhances its superconducting critical temperature (Tc ). In this work, a buckled plumbene-Au Kagome superstructure grown by depositing Au on Pb(111) is investigated. The superconducting gap monitored by temperature-dependent scanning tunneling microscopy/spectroscopy shows that the buckled plumbene-Au Kagome superstructure not only has an enhanced Tc with respect to that of a monolayer Pb but also possesses a higher value than what owned by a bulk Pb substrate. By combining angle-resolved photoemission spectroscopy with density functional theory, the monolayer Au-intercalated low-buckled plumbene sandwiched between the top Au Kagome layer and the bottom Pb(111) substrate is confirmed and the electron-phonon coupling-enhanced superconductivity is revealed. This work demonstrates that a buckled plumbene-Au Kagome superstructure can enhance superconducting Tc and Rashba effect, effectively triggering the novel properties of a plumbene.

3.
Sci Data ; 10(1): 91, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788235

RESUMEN

Defects to popular two-dimensional (2D) transition metal dichalcogenides (TMDs) seriously lower the efficiency of field-effect transistor (FET) and depress the development of 2D materials. These atomic defects are mainly identified and researched by scanning tunneling microscope (STM) because it can provide precise measurement without harming the samples. The long analysis time of STM for locating defects in images has been solved by combining feature detection with convolutional neural networks (CNN). However, the low signal-noise ratio, insufficient data, and a large amount of TMDs members make the automatic defect detection system hard to be applied. In this study, we propose a deep learning-based atomic defect detection framework (DL-ADD) to efficiently detect atomic defects in molybdenum disulfide (MoS2) and generalize the model for defect detection in other TMD materials. We design DL-ADD with data augmentation, color preprocessing, noise filtering, and a detection model to improve detection quality. The DL-ADD provides precise detection in MoS2 (F2-scores is 0.86 on average) and good generality to WS2 (F2-scores is 0.89 on average).

4.
J Adv Res ; 43: 147-161, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36585105

RESUMEN

INTRODUCTION: Considerable evidence has linked periodontitis (PD) to hypertension (HTN), but the nature behind this connection is unclear. Dysbiosis of oral microbiota leading to PD is known to aggravate different systematic diseases, but the alteration of oral microbiota in HTN and their impacts on blood pressure (BP) remains to be discovered. OBJECTIVES: To characterize the alterations of oral and gut microbiota and their roles in HTN. METHODS: We performed a cross-sectional (95 HTN participants and 39 controls) and a 6-month follow-up study (52 HTN participants and 26 controls) to analyze the roles of oral and gut microbiota in HTN. Saliva, subgingival plaques, and feces were collected for 16S rRNA gene sequencing or metagenomic analysis. C57BL/6J mice were pretreated with antibiotics to deplete gut microbiota, and then transplanted with human saliva by gavage to test the impacts of abnormal oral-gut microbial transmission on HTN. RESULTS: BP in participants with PD was higher than no PD in both cross-sectional and follow-up cohort. Relative abundances of 14 salivary genera, 15 subgingival genera and 10 gut genera significantly altered in HTN and those of 7 salivary genera, 12 subgingival genera and 6 gut genera significantly correlated with BP. Sixteen species under 5 genera were identified as oral-gut transmitters, illustrating the presence of oral-gut microbial transmission in HTN. Veillonella was a frequent oral-gut transmitter stably enriched in HTN participants of both cross-sectional and follow-up cohorts. Saliva from HTN participants increased BP in hypertensive mice. Human saliva-derived Veillonella successfully colonized in mouse gut, more abundantly under HTN condition. CONCLUSIONS: PD and oral microbiota are strongly associated with HTN, likely through oral-gut transmission of microbes. Ectopic colonization of saliva-derived Veillonella in the gut may aggravate HTN. Therefore, precise manipulations of oral microbiota and/or oral-gut microbial transmission may be useful strategies for better prevention and treatment of HTN.


Asunto(s)
Microbioma Gastrointestinal , Hipertensión , Microbiota , Periodontitis , Humanos , Animales , Ratones , Microbioma Gastrointestinal/fisiología , ARN Ribosómico 16S/genética , Estudios Transversales , Estudios de Seguimiento , Ratones Endogámicos C57BL
5.
Front Neurol ; 12: 691378, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34434159

RESUMEN

Objective: This study aimed to explore the potential mechanism of peritumoral brain edema (PTBE) formation in vestibular schwannoma (VS) by detecting intra-tumoral vascular endothelial growth factor (VEGF) expression. Methods: Between January 2018 and May 2021, 15 patients with PTBE and 25 patients without PTBE were included in the analysis. All patients enrolled in our study underwent surgery in our institution. Expression level of VEGF and microvessel density (MVD) between the two groups were analyzed. Edema index (EI) of each patient with PTBE was calculated. Results: In the PTBE group, the average of EI was 1.53 ± 0.22. VEGF expression levels were significantly enhanced in the PTBE group compared with the non-PTBE group (p < 0.001). The expression level of VEGF in the PTBE group and non-PTBE group was 1.14 ± 0.21 and 0.52 ± 0.09, respectively. Similarly, there were significantly different amounts of MVD in the two groups (p < 0.001). The amount of MVD in the PTBE group and non-PTBE group was 11.33 ± 1.59 and 6.28 ± 1.77, respectively. Correlation analysis showed a highly significant positive correlation between VEGF and MVD (r = 0.883, p < 0.001) and VEGF and EI (r = 0.876, p < 0.001). Conclusion: Our study confirmed the close relationship among VEGF expression, tumor angiogenesis, and formation of PTBE in VS patients. It may be possible to develop new effective therapies to attenuate PTBE in VS for alleviation of symptoms and reduction of postoperative complication.

6.
Thyroid ; 30(12): 1820-1830, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32746755

RESUMEN

Background: We aimed to examine the association of urinary iodine concentration with Hashimoto's thyroiditis (HT) risk, and particularly, to investigate whether the HT-related genetic variations might modify the effects of urinary iodine on HT in the Chinese Han population. Methods: We conducted a case-control study with 1723 Chinese (731 cases, 992 controls). The associations between urinary iodine concentration and HT risk were analyzed using logistic regression models. The effects of interactions between the genetic risk scores (GRSs) and urinary iodine on HT risk were assessed by including the respective interaction terms in the models. We also applied restricted cubic spline regression to estimate the possible nonlinear relationship. The multinomial logistic regression models were performed to determine the associations of urinary iodine with euthyroid-HT and hypothyroidism-HT. Results: After controlling for potential confounders, the odds of HT increased with increasing quartiles of urinary iodine concentration: adjusted odds ratios (ORs) and 95% confidence intervals [CIs] were 1.45 [1.06-1.99], 1.66 [1.17-2.34], and 2.07 [1.38-3.10] for the quartiles 2, 3, and 4, respectively, compared with the first quartile (p for trend <0.001). Multivariable restricted cubic spline regression analysis further demonstrated that there was a near-linear association between urinary iodine concentration and HT risk (p-overall <0.001; p-nonlinear = 0.074). However, we did not find significant interactions between urinary iodine and GRSs on the risk of HT (all p for interaction >0.05). Interestingly, we found that each increment of urinary iodine was associated with a more than twofold increase in the odds of hypothyroidism-HT (adjusted OR = 2.64 [CI = 1.73-4.05]), but not with euthyroid-HT (p > 0.05). Conclusions: Higher urinary iodine concentration was associated with increased risk of HT, and this association was near linear, indicating that increased urinary iodine has a continuous and graded impact on HT risk. Moreover, the iodine-HT association was not modified by genetic predisposition to HT. Interestingly, urinary iodine concentration was significantly associated with increased risk of hypothyroidism.


Asunto(s)
Enfermedad de Hashimoto/genética , Enfermedad de Hashimoto/orina , Yodo/orina , Polimorfismo de Nucleótido Simple , Adulto , Pueblo Asiatico/genética , Biomarcadores/orina , Estudios de Casos y Controles , China/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Enfermedad de Hashimoto/diagnóstico , Enfermedad de Hashimoto/etnología , Humanos , Hipotiroidismo/diagnóstico , Hipotiroidismo/etnología , Hipotiroidismo/orina , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo
7.
Neurosci Lett ; 617: 160-5, 2016 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-26742642

RESUMEN

OBJECTIVE: The underlying pathology of brain leading to cognitive impairment in Parkinson's disease (PD) remains poorly understood. The aim of our study was to test the hypothesis that mild cognitive impairment (MCI) in PD may be related to atrophy of special gray matter regions. METHODS: High-resolution T1-weighted magnetic resonance images of the brains and comprehensive cognitive function tests were acquired in 37 PD patients and 21 healthy controls (HC) from September 2013 to October 2014. Patients were divided into two groups: PD with MCI (PD-MCI, n=18) and PD with normal cognition (PDNC, n=19). Gray matter density differences were analyzed using voxel-based morphometry (VBM). VBM and cognitive results, UPDRS scores and Hoehn-Yahr stages were compared between PD-MCI, PDCN and HC group, and correlation analyses were performed between those brain areas and cognition scores, UPDRS scores and disease duration, which showed significant group differences. RESULTS: The demographic data and motor severity among three groups were similar. However, comprehensive cognitive function results were more severe in PD-MCI than the other two groups. Compared to the HC group, the PDNC group showed reductions in gray matter density in frontal, temporal, parietal, bilateral insula lobes and many other regions of brain. Besides above changes, the PD-MCI group also revealed gray matter concentration decrease in left hippocampus and thalamus, and these changes still remained when compared with the PDNC group. The HC group did not show any more areas of atrophy in gray matter than others. Gray matter loss in PD represented significant correlations with global cognitive scores, motor severity or disease duration in some of these atrophic regions. CONCLUSION: The initial stages of cognitive function decline in patients with PD is closely associated with gray matter atrophy in left hippocampus and thalamus. These two regions may serve as potential imaging biomarkers for PD-MCI.


Asunto(s)
Encéfalo/patología , Disfunción Cognitiva/patología , Sustancia Gris/patología , Enfermedad de Parkinson/patología , Anciano , Atrofia/patología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/psicología
8.
J Oral Pathol Med ; 44(3): 193-200, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25047743

RESUMEN

BACKGROUND: Glutathione S transferase pi (GSTP1) is a member of phase II detoxification enzymes as a major regulator of cell signaling in response to stress, hypoxia, growth factors, and other stimuli. The clinical role of GSTP1 in cancer is still unclear. The aim of this study was to investigate the serum GSTP1 level in patients with oral squamous cell carcinoma (OSCC) and the GSTP1 expression in tissue samples from patients with OSCC and OSCC lines. METHODS: One hundred and sixty-six patients with OSCC and 120 normal persons were used to screen potential serum peptide biomarkers using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Serum GSTP1 concentration was detected in 18 patients with OSCC and 18 normal persons using ELISA. Immunohistochemistry was used to detect GSTP1 expression in tissue samples from twenty-eight OSCC patients. Western blot and real-time PCR were used to detect GSTP1 expression in nine OSCC lines. RESULTS: Decreased GSTP1 concentration was found in the patients with OSCC compared with the normal persons by MALDI-TOF-MS, which was then confirmed by ELISA (P = 0.019). Decreased GSTP1 mRNA level and protein expression were also found in the OSCC lines. Decreased GSTP1 expression was found correlating with pathological differentiation grade in the tissue samples from OSCC patients, a lower GSTP1 expression indicating a poorer pathological differentiation grade (P = 0.041). CONCLUSIONS: These results suggest that decreased GSTP1 expression in patients with OSCC and a lower GSTP1 expression indicating a poorer pathological differentiation grade in OSCC tissue samples.


Asunto(s)
Carcinoma de Células Escamosas/patología , Gutatión-S-Transferasa pi/sangre , Neoplasias de la Boca/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/enzimología , Línea Celular , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Nanopartículas de Magnetita , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/sangre , Neoplasias de la Boca/enzimología , Clasificación del Tumor , Estadificación de Neoplasias , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
9.
Shanghai Kou Qiang Yi Xue ; 22(1): 58-62, 2013 Feb.
Artículo en Chino | MEDLINE | ID: mdl-23552783

RESUMEN

PURPOSE: To analyze the causes of atrophic glossitis(AG) and to explore the relationship between AG and serum cobalamin, folate levels. METHODS: A total of 213 patients with AG treated from Jan.1979 to Jun. 2010 were analyzed for the causes of AG. Serum cobalamin, folate levels and complete blood count were tested in newly enrolled AG patients from Sep. 2010 to Aug. 2011. All data were analyzed with SPSS 16.0 software package for Student's t test. RESULTS: There were 97 AG patients (45.4%) suffering from megaloblastic anemia (MA)/ macrocytosis. Among the 72 newly enrolled AG patients, fifty had cobalamin deficiency. Meanwhile, serum folate levels were increased in cobalamin deficiency group. CONCLUSIONS: Cobalamin deficiency is the common cause both of MA/macrocytosis and AG, also may be the main cause of AG. Furthermore, AG may be the early clinical manifestation of cobalamin deficiency.


Asunto(s)
Glositis , Deficiencia de Vitamina B 12 , Vitamina B 12 , Anemia Megaloblástica , Ácido Fólico , Humanos
10.
Cell Res ; 13(4): 285-94, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12974618

RESUMEN

To lay background for studying rejection mechanisms in xenotransplantation and developing the strategies for intervention, class I genes of swine leukocyte antigens (SLA) of three Chinese pig strains Bm, Gz and Yn were cloned and sequenced. The cDNA of the class I loci P1 and P14 were amplified by RT-PCR and subjected to insert into sequencing vectors. All six allelic sequences we examined, each two for one Chinese strain, are not identical to those reported, which allows these novel sequences receiving their accession numbers AY102467-AY102472 from GenBank. This study further reveals that the homologies of MHC class I genes in their primary structures and the deduced amino acids between Chinese pigs (SLA) and human (HLA-A*0201) are better than those between pigs and mice (H-2Db/H-2Kb). The comparison also indicates that the amino acid residues critical for recognition by human KIRs are altered in the swine class I molecules. The amino acids responsible for binding human CD8 coreceptor are largely conserved although there are two critical residues substituted. A functional test indicated that the human T cells specific for the prokaryotically expressed SLA P1 protein could respond quite well in vitro to the class I-positive swine chondrocytes and PBMCs in presence of human APCs. This implies that, due to the substitution of two critical residues, the inaccessibility of human CD8 coreceptor to swine class I molecule might be contributable to the indirect pathway that the human T cells have to use for recognizing the SLA class I xenogeneic antigens.


Asunto(s)
Alelos , Genes MHC Clase I , Porcinos , Trasplante Heterólogo/inmunología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Antígenos CD8/inmunología , Antígenos CD8/metabolismo , Línea Celular , Rechazo de Injerto , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Células Asesinas Naturales/metabolismo , Ratones , Datos de Secuencia Molecular , Receptores Inmunológicos/metabolismo , Receptores KIR , Alineación de Secuencia , Porcinos/genética , Porcinos/inmunología , Linfocitos T/citología , Linfocitos T/fisiología
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