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1.
Phys Chem Chem Phys ; 22(22): 12706-12712, 2020 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-32459256

RESUMEN

All-inorganic cesium lead triiodide (CsPbI3) perovskite has been widely researched due to its outstanding photovoltaic properties. At room temperature, there are two orthorhombic CsPbI3 phases (black γ-CsPbI3 perovskite and yellow δ-CsPbI3 non-perovskite). In this study, these two polymorphic structures have been studied via density functional theory calculations in respect to their electronic and elastic properties. Our calculation results give full mapping of Young's moduli of the γ-CsPbI3 structure for all crystallographic orientations, which reveal that the optimum directions for stabilizing the γ-CsPbI3via strain are approximately along 〈012〉. Moreover, we found that these two polymorphs have distinct stiffness along respective octahedral chains due to their different kinds of octahedral connections. Furthermore, the calculated band structures and density of states disclose that both phases have direct bandgaps, and the bandgap of δ-CsPbI3 is much wider due to its weak Pb 6p-I 5p antibonding coupling in the conduction band and low octahedral connectivity. Our findings provide fundamental elastic and electronic insights which are instructive for strain engineering of photovoltaic γ-CsPbI3.

2.
J Am Chem Soc ; 141(23): 9134-9139, 2019 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-31131600

RESUMEN

The flexible organic amine cations on the interfaces of two-dimensional (2D) hybrid organic-inorganic perovskite nanosheets could form relaxed structures, which would lead to exotic optoelectronic properties but are hard to understand. Here, the unusual interfacial relaxation of nanosheets exfoliated from an orthorhombic 2D lead halide perovskite, [(C6H5CH2NH3)2]PbCl4, is interrogated via ultrafast second-harmonic generation (SHG) spectroscopy. The in-plane SHG intensity anisotropy of these nanosheets is found to decrease with reducing layer thickness. Combined first-principles calculations and Monte Carlo simulations reveal that the induced second-order polarization arises primarily from the (C6H5CH2NH3)+ cations; and these organic amine cations form significantly reorganized conformations with decreasing nanosheet thickness due to weakened van der Waals interactions. Because the orientations of organic components at the interface determine their electric properties and specifically the dipolar susceptibility, the resulting structure leads to striking changes in the SHG properties.

3.
Signal Transduct Target Ther ; 9(1): 153, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38937446

RESUMEN

Epidermal growth factor receptor (EGFR) is reportedly overexpressed in most esophageal squamous cell carcinoma (ESCC) patients, but anti-EGFR treatments offer limited survival benefits. Our preclinical data showed the promising antitumor activity of afatinib in EGFR-overexpressing ESCC. This proof-of-concept, phase II trial assessed the efficacy and safety of afatinib in pretreated metastatic ESCC patients (n = 41) with EGFR overexpression (NCT03940976). The study met its primary endpoint, with a confirmed objective response rate (ORR) of 39% in 38 efficacy-evaluable patients and a median overall survival of 7.8 months, with a manageable toxicity profile. Transcriptome analysis of pretreatment tumors revealed that neurotrophic receptor tyrosine kinase 2 (NTRK2) was negatively associated with afatinib sensitivity and might serve as a predictive biomarker, irrespective of EGFR expression. Notably, knocking down or inhibiting NTRK2 sensitized ESCC cells to afatinib treatment. Our study provides novel findings on the molecular factors underlying afatinib resistance and indicates that afatinib has the potential to become an important treatment for metastatic ESCC patients.


Asunto(s)
Afatinib , Resistencia a Antineoplásicos , Receptores ErbB , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Inhibidores de Proteínas Quinasas , Receptor trkB , Humanos , Afatinib/farmacología , Afatinib/uso terapéutico , Receptores ErbB/genética , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/patología , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/patología , Inhibidores de Proteínas Quinasas/farmacología , Receptor trkB/genética , Receptor trkB/antagonistas & inhibidores , Línea Celular Tumoral , Adulto , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glicoproteínas de Membrana
4.
Am J Transl Res ; 15(1): 493-501, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36777856

RESUMEN

OBJECTIVE: To explore the relationship between galectin-1, -3 and unexplained infertility and the effect on endometrial receptivity. METHODS: The clinical data of 100 female patients at childbearing age coming to Xingtai People's Hospital from February 2019 to February 2021 were collected retrospectively. Based on normal pregnancy or not, 50 infertility patients were placed into an infertility group, and 50 patients with normal pregnancy history were placed into a normal group. The mRNA and protein levels of galectin-1, -3, endometrial wave-like activity, endometrial thickness, uterine artery pulsatility index (PI), resistance index (RI), end diastolic velocity (EDV) and peak systolic velocity (PSV) ratio (S/D = PSV/EDV) were compared between the two groups of patients. RESULTS: The mRNA and protein levels of galectin-1, -3 in the infertile group were lower than those in the normal group (P<0.05). In addition, the endometrial wave-like activity in the infertile group was more than that in the normal group (P<0.05). The endometrial thickness was less, while PI, RI and S/D were higher in the infertile group than those in the normal group (P<0.05). CONCLUSION: The low mRNA and protein expressions of galectin-1, -3 in unexplained infertility can affect endometrial receptivity, which may be closely related to unexplained infertility.

5.
Am J Transl Res ; 15(9): 5683-5690, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37854201

RESUMEN

OBJECTIVE: To investigate the efficacy of ZM suture combined with early functional exercise in repairing flexor tendons and its impact on finger function recovery in patients. METHODS: A retrospective analysis was conducted on 60 patients who sought medical treatment at the Orthopedics Hospital of Xingtai City from August 2019 to August 2022. Among them, 29 patients treated with the modified Kessler suture technique were assigned to the control group, while 31 patients treated with ZM suture technique were assigned to the observation group. Both groups of patients underwent early functional exercise after surgery and were followed up regularly for 6 months. Finger function, grip strength, pinch strength at 6 months after operation, upper limb function before and after treatment, visual analog pain scale (VAS) at 1 and 2 weeks postoperatively, quality of life, and incidence of complications were compared between the two groups. The risk factors affecting the prognosis of patients were analyzed. RESULTS: At 6 months postoperatively, the observation group showed significantly better finger function, grip strength and grip strength ratio, and upper limb function compared to the control group (all P<0.05). The observation group had significantly lower VAS scores at 1 and 2 weeks postoperatively and a significantly lower incidence of complications compared to the control group, while their quality of life was significantly better than that of the control group (all P<0.05). The choice of treatment method is an independent risk factor affecting the prognosis of patients (P<0.05). CONCLUSION: The ZM suture technique combined with early functional exercise has significant efficacy in repairing flexor tendons, effectively promoting finger function recovery in patients. It is also associated with a high level of safety and warrants clinical application and promotion.

6.
Front Surg ; 9: 964044, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36684318

RESUMEN

Objective: A review argues that polo-like kinase 5 (PLK5) may be linked to unfavorable prognosis in non-small cell lung cancer (NSCLC) patients, which contradicts the discoveries from The Human Protein Atlas database (derived from TCGA analysis). This study intended to comprehensively confirm the association of PLK5 with clinical characteristics and prognosis in NSCLC patients. Methods: This two-center, retrospective, cohort study enrolled 210 NSCLC patients receiving surgical resection. PLK5 protein and mRNA were detected by immunohistochemistry and RT-qPCR in tumor and nontumor tissues. Moreover, RNA FPKM data for 994 lung cancer patients were obtained from The Human Protein Atlas database. Results: PLK5 protein was decreased in tumor tissue compared to nontumor tissue (P < 0.001). Additionally, decreased PLK5 protein was linked with increased pathological grade (P = 0.002), lymph node metastasis presence (P = 0.001), elevated tumor-node-metastasis (TNM) stage (P = 0.003), and abnormal cancer antigen 125 (CA125) (P = 0.002). Meanwhile, low PLK5 protein was correlated with shortened disease-free survival (DFS) (P = 0.007) and overall survival (OS) (P = 0.038); further multivariable Cox regression analysis revealed that low PLK5 protein independently predicted unfavorable DFS (hazard ratio = 0.573, P = 0.022). PLK5 mRNA was reduced in tumor tissue compared with nontumor tissue (P < 0.001); its decline was linked with enhanced pathological grade (P = 0.034), climbed TNM stage (P = 0.032), and abnormal CA125 (P = 0.002). Furthermore, low PLK5 mRNA was correlated with unfavorable DFS (P = 0.046). The Human Protein Atlas database also disclosed the link between low PLK5 mRNA and worse OS (P = 0.046). Conclusion: A PLK5 decrement reflects anabatic tumor burden and poor prognosis in NSCLC patients.

7.
Mater Horiz ; 9(8): 2207-2214, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35708167

RESUMEN

Negative and zero thermal expansion (NTE and ZTE) materials are widely adopted to eliminate the harmful effect from the "heat expansion and cool contraction" effect and frequently embrace novel fundamental physicochemical mechanisms. To date, the manipulation of NTE and ZTE materials has mainly been realized by chemical component regulation. Here, we propose another method by making use of the anisotropy of thermal expansion in noncubic single crystals, with maximal tunability from the integration of linear NTE, ZTE and positive thermal expansion (PTE). We demonstrate this concept in borate optical crystals of AEB2O4 (AE = Ca or Sr) to make the light transmission temperature-independent by counterbalancing the thermal expansion and thermo-optics coefficient. We further reveal that such a unique thermal expansion behavior in AEB2O4 arises from the synergetic thermal excitation of bond stretching in ionic [AEO8] and rotation between covalent [BO3] groups. This work has significant implications for understanding the thermal excitation of lattice vibrations in crystals and promoting the functionalization of anomalous thermal expansion materials.

8.
Biomed Pharmacother ; 140: 111750, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34051615

RESUMEN

Advanced glycation end products (AGEs) are a group of complex compounds generated by nonenzymatic interactions between proteins and reducing sugars or lipids. AGEs accumulate in vivo and activate various signaling pathways closely related to the occurrence of various chronic metabolic diseases. In this paper, we describe the process through which AGEs are formed, the classification of AGEs, and biological effects of AGEs on human health. Most importantly, we review recent progress in natural compound-based AGE formation inhibitors. Major classes of natural inhibitors, including polyphenols, polysaccharides, terpenoids, vitamins and alkaloids, have been described. Their mechanisms of action have been summarized as scavenging free radicals, chelating metal ions, capturing active carbonyl compounds, protecting protein glycation sites, and lowering blood glucose levels. Although these natural compounds have good antiglycation activity, to date, they are not widely used in the clinic, likely because of their low content levels. However, these natural compounds and their molecular frameworks will play a valuable role in inspiring drug discovery.


Asunto(s)
Productos Biológicos/farmacología , Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Animales , Productos Finales de Glicación Avanzada/metabolismo , Humanos
9.
Research (Wash D C) ; 2021: 9850151, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34268497

RESUMEN

Metal-organic frameworks (MOFs) have attracted significant attention in the past two decades due to their diverse physical properties and associated functionalities. Although numerous advances have been made, the acoustic properties of MOFs have attracted very little attention. Here, we systematically investigate the acoustic velocities and impedances of 19 prototypical MOFs via first-principle calculations. Our results demonstrate that these MOFs exhibit a wider range of acoustic velocities, higher anisotropy, and lower acoustic impedances than their inorganic counterparts, which are ascribed to their structural diversity and anisotropy, as well as low densities. In addition, the piezoelectric properties, which are intimately related to the acoustic properties, were calculated for 3 MOFs via density functional perturbation theory, which reveals that MOFs can exhibit significant piezoelectricity due to the ionic contribution. Our work provides a comprehensive study of the fundamental acoustic properties of MOFs, which could stimulate further interest in this new exciting field.

10.
Open Med (Wars) ; 15: 190-197, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32190744

RESUMEN

Lung cancer is one of the most harmful malignant tumors to human health. The accurate judgment of the pathological type of lung cancer is vital for treatment. Traditionally, the pathological type of lung cancer requires a histopathological examination to determine, which is invasive and time consuming. In this work, a novel residual neural network is proposed to identify the pathological type of lung cancer via CT images. Due to the low amount of CT images in practice, we explored a medical-to-medical transfer learning strategy. Specifically, a residual neural network is pre-trained on public medical images dataset luna16, and then fine-tuned on our intellectual property lung cancer dataset collected in Shandong Provincial Hospital. Data experiments show that our method achieves 85.71% accuracy in identifying pathological types of lung cancer from CT images and outperforming other models trained with 2054 labels. Our method performs better than AlexNet, VGG16 and DenseNet, which provides an efficient, non-invasive detection tool for pathological diagnosis.

11.
Biosci Rep ; 40(6)2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32342983

RESUMEN

Preeclampsia (PE), a common obstetrical disorder, is characterized by impaired migration and invasion abilities of trophoblastic cells. MicroRNA-183-5p (miR-183) was reported to regulate cell migration and invasion in various types of human cancers; however, its role in the pathogenesis of PE remains elusive. Herein, we investigated the role of miR-183 in HTR-8/SVneo trophoblast cells invasion and migration and explored the underlying mechanism. Our results showed that miR-183 was significantly up-regulated in placental tissues from pregnant women compared with that in normal pregnant women. Overexpression of miR-183 inhibited proliferation, migration and invasion, as well as induced apoptosis in HTR-8/SVneo cells. Otherwise, down-regulation of miR-183 achieved the opposite effects. Bioinformatics prediction and luciferase reporter assay confirmed that matrix metalloproteinase-9 (MMP-9) is a target of miR-183. In addition, MMP-9 expression was significantly down-regulated, and inversely correlated with the miR-183 level in placental tissues from pregnant women with severe PE. Down-regulation of MMP-9 suppressed the trophoblast cell invasion and migration, whereas overexpression of MMP-9 promoted cell invasion and migration in HTR-8/SVneo cells. More importantly, up-regulation of MMP-9 reversed the inhibitory effects of miR-183 on cell invasion and migration in trophoblast cells. Collectively, our findings suggested that miR-183 may play critical roles in the pathogenesis of PE and serve as a potential biomarker for severe PE.


Asunto(s)
Movimiento Celular , Metaloproteinasa 9 de la Matriz/metabolismo , MicroARNs/metabolismo , Preeclampsia/enzimología , Trofoblastos/enzimología , Adulto , Apoptosis , Estudios de Casos y Controles , Línea Celular , Proliferación Celular , Femenino , Regulación Enzimológica de la Expresión Génica , Humanos , Metaloproteinasa 9 de la Matriz/genética , MicroARNs/genética , Preeclampsia/genética , Preeclampsia/patología , Embarazo , Transducción de Señal , Trofoblastos/patología , Adulto Joven
12.
J Phys Chem Lett ; 11(14): 5728-5733, 2020 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-32598149

RESUMEN

Hybrid organic-inorganic perovskites have emerged as promising thermoelectric materials due to their attractive figure of merits. To further reduce their thermal conductances (G) and improve the thermoelectric efficiencies, fabrication of phononic crystals (PnCs) could be an effective approach. In this work, CH3NH3PbI3-based PnCs were developed and their thermal transports were engineered by optimizing the configurations of both basal bodies and scatterers. Our cross-scale simulations demonstrate that low relative G can be achieved in CH3NH3PbI3 PnCs with large scatterers but low-symmetric PnC lattices, basal bodies, and scatterers. Moreover, we discovered the increased disorder of CH3NH3+ cations from tetragonal to cubic transition significantly increases the phonon velocities and reverses the phonon transport from diffusive to quasi-ballistic, leading to an abnormal reduction of relative G. This work provides a new pathway for engineering thermal conductivity of hybrid perovskites and improving the performance of corresponding devices.

13.
Nat Commun ; 11(1): 5593, 2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33154363

RESUMEN

Anomalous mechanical materials, with counterintuitive stress-strain responding behaviors, have emerged as novel type of functional materials with highly enhanced performances. Here we demonstrate that the materials with coexisting negative, zero and positive linear compressibilities can squeeze three-dimensional volume compressibility into one dimension, and provide a general and effective way to precisely stabilize the transmission processes under high pressure. We propose a "corrugated-graphite-like" structural model and discover lithium metaborate (LiBO2) to be the first material with such a mechanical behavior. The capability to keep the flux density stability under pressure in LiBO2 is at least two orders higher than that in conventional materials. Our study opens a way to the design and search of ultrastable transmission materials under extreme conditions.

14.
RSC Adv ; 9(23): 13153-13158, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35520795

RESUMEN

Coordination polymer based dietary supplement tablets are commonly consumed in our daily life and play an important role in the pharmaceutical industry. To fully understand their tableting process, their mechanical properties need to be comprehensively studied. In this work, the elastic and hydrostatic behaviour of a zinc supplement, zinc glycinate hydrate (Zn[O2CCH2NH2]2·H2O), have been studied via density functional theory (DFT) calculations and high-pressure synchrotron powder X-ray diffraction. This material has a pseudo-layered structure and can be successfully exfoliated into nanosheets. The DFT calculated elastic moduli along the principal axes (13.84-36.11 GPa) indicate a significant elastic anisotropy of ZnG as expected for a layered system, and the directional dependent elastic modulus can be corroborated with the underlying atomic structure. In addition, the calculated B/G ratios (1.30-3.83) according to Pugh's criterion reveal that ZnG could be brittle under uniaxial stress (B and G are bulk modulus and shear modulus, respectively). Furthermore, the measured B is ∼31 GPa, which lies in the middle of the values between inorganic dietary supplements and small organic drug crystals. These results provide some quantitative information about the tableting process of the hybrid dietary supplement which could be different from their inorganic and organic pharmaceutical counterparts.

15.
Chem Sci ; 10(5): 1309-1315, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-30809345

RESUMEN

Very few materials expand two-dimensionally under pressure, and this extremely rare phenomenon, namely negative area compressibility (NAC), is highly desirable for technological applications in pressure sensors and actuators. Hitherto, the few known NAC materials have dominantly been limited to 2D crystals bonded via coordination interactions while other 2D systems have not been explored yet. Here, we report the large NAC of a hydrogen-bonded 2D supramolecular coordination complex, Zn(CH3COO)2·2H2O, with a synergistic microscopic mechanism. Our findings reveal that such an unusual phenomenon, over a wide pressure range of 0.15-4.44 GPa without the occurrence of any phase transitions, arises from the complex cooperation of intra-layer coordination and hydrogen-bonding interactions, and inter-layer van der Waals forces. In addition, we propose that these NAC crystals could have important applications as pressure-converting materials in ultrasensitive pressure sensing devices.

16.
Int J Biol Macromol ; 108: 1158-1164, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29154876

RESUMEN

Osteoarthritis (OA) is a common joint disease characterized by cartilage degradation. Chondroitin sulfate from shark (CS-S) has a good effect on OA in clinical, but due to source limited of CS from shark. Therefore, it is important to find a novel CS source with similar efficacy to CS-S in the treatment of OA. Herein, we reported a therapeutic effect of CS from scophthalmus maximus (CS-SM) for treating OA in rats. The OA model was established. After intervention with CS-SM by intragastric administration. Our results showed that CS-SM could protect articular cartilage in OA, inhibit the degradation of cartilage, decrease the apoptosis of chondrocytes, decline the content of interleukin-1, tumor necrosis factor-α and Prostaglandins E2 in synovial fluid, down-regulate the protein expression of matrix metalloproteinase-1 and up-regulate the protein expression of tissue inhibitor of metalloproteinase-1. Our results suggest that oral CS from SM is a new potential therapy for OA.


Asunto(s)
Sulfatos de Condroitina/farmacología , Peces Planos , Osteoartritis/tratamiento farmacológico , Animales , Cartílago Articular/efectos de los fármacos , Cartílago Articular/patología , Sulfatos de Condroitina/uso terapéutico , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Metaloproteinasa 1 de la Matriz/metabolismo , Osteoartritis/metabolismo , Osteoartritis/patología , Ratas , Líquido Sinovial/efectos de los fármacos , Líquido Sinovial/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo
17.
Cancer Biomark ; 20(3): 283-288, 2017 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-28946561

RESUMEN

BACKGROUND: Blood-circulating miRNAs have been reported to act as potential biomarkers in various cancers including non-small cell lung cancer (NSCLC). OBJECTIVE: This study was to assess serum miR-98 levels in NSCLC patients and explore its potential prognostic value. METHODS: The relative expression levels of miR-98 were detected by quantitative RT-PCR in the sera of 127 NSCLC patients and 60 healthy controls. RESULTS: Our results showed that serum miR-98 expression was down-regulated in NSCLC patients compared with healthy controls. Receiver operating characteristic (ROC) curve analysis suggested that serum miR-98 could be used as a potential marker in the diagnosis of NSCLC. In addition, decreased serum miR-98 was positively correlated with worse TNM stage, lymph node metastasis, as well as unfavorable overall survival. Multivariate Cox regression analysis confirmed that serum miR-98 expression was an independent prognostic factor for NSCLC. CONCLUSIONS: Therefore, serum miR-98 might be useful as a promising biomarker for prognosis prediction of NSCLC.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma de Pulmón de Células no Pequeñas/sangre , Neoplasias Pulmonares/sangre , MicroARNs/sangre , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Casos y Controles , Regulación hacia Abajo , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico
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