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1.
J Phys Condens Matter ; 32(6): 065004, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31470426

RESUMO

Recently, the traditional infrared photodetectors (PDs) shows limited application in various areas, due to the narrow band-gap, high cost and even complex manufacturing process. In this situation, scientist have paid much attention to achieve the ultra broadband PDs from the deep ultraviolet to the near infrared. The energy band engineering for two-dimensional (2D) van der Waals heterojunction with free chemical dangling bonds is an effective method to fabricate High-performance Photodetectors. In this work, we employ density functional calculation to construct a type-II CdTe/MoS2 heterostructure and calculate its electronic properties. The results reveal that the CdTe/MoS2 has the narrow band gap of 0.64 eV and electrons transfer from the CdTe to MoS2 layer, which promotes the separation of photogenerated carriers and enhance the photoelectron conversion efficiency. Driven by the smaller band gap, it can respond to near infrared, visible and ultraviolet light, demonstrating it the promising application for solar cell. Furthermore, the analysis of molecules adsorption and band edge alignment indicates that the CdTe/MoS2 is prone to capture H2O and release the H2 molecules, which is conductive to the photocatalytic water splitting for hydrogen generation. Our work suggests that the CdTe/MoS2 heterostructure is a potential candidate as a solar cell and even photocatalyst, and also provides a new sight for experimental and theoretical research to design a highly efficient device.

2.
J Med Virol ; 92(1): 34-44, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31429942

RESUMO

Mounting evidence indicates that serum soluble E-cadherin (sE-cadherin) serves as an important player in various physiological and pathological processes. However, the crosstalk between serum sE-cadherin and oxidative stress in chronic hepatitis B (CHB) remains to be illustrated. The main purpose of this study is to explore the molecular mechanisms underlying the function of sE-cadherin in CHB virus infection. Levels of serum sE-cadherin, total antioxidant capacity (TAC), glutathione (GSH), superoxide dismutase (SOD), total oxidant activity (TOA), NADPH oxidase 2 (NOX2), and malondialdehyde (MDA), from 51 patients with hepatitis B envelope antigen (HBeAg)-negative CHB, 54 patients with HBeAg-positive CHB, and 109 healthy individuals were detected by enzyme-linked immunosorbent assay. In our study, patients with CHB showed significantly higher serum sE-cadherin levels than healthy individuals (P < .01). Furthermore, we also found that the serum sE-cadherin levels were significantly negatively correlated with TAC, antioxidant enzymes (GSH and SOD) in patients with CHB, and that serum sE-cadherin concentrations were significantly positively correlated with liver enzyme markers (alanine transaminase and aspartate aminotransferase) and oxidative markers (TOA, NOX2, and MDA) in patients with CHB. Therefore, serum sE-cadherin may act as a new candidate biomarker for reflecting inflammation and oxidative stress status in the development and progression of hepatitis B virus infection.

3.
J Phys Condens Matter ; 32(6): 065002, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31648212

RESUMO

Electroluminescence devices based on all-inorganic halide perovskite material with excellent luminescence performance have been studied extensively in recent years. However, the important role for the electrodes of electroluminescence devices is payed few attention by theoretical and experimental studies. Appropriate electrodes can reduce the Schottky barrier height to decrease the energy loss, and prevent the metal impurities from diffusing into the perovskite material to generate deep traps levels, which improves the luminous efficiency and lifetime of devices. In this paper, not only the interface effects between CsPbBr3 and common metal electrode (Ag, Au, Ni, Cu and Pt) are studied by first-principle calculations, but also the diffusion effects of metal electrode atom into the CsPbBr3 layer are also explored by nudged elastic band calculations. The calculated results show the metal Ag is more suitable for the cathode for CsPbBr3 electroluminescence devices, while the metal Pt is more applicable for the anode. Based on the overall consideration about the interface effects and diffusion effects of the CsPbBr3-metal electrode junctions, the essential principle is analyzed. The work provides theoretical guidance for how to select the right electrode for the electroluminescence performance of all-inorganic halide perovskite. The critical factor of Schottky barrier height between the electrode and the light-emitting semiconductor, and transition level generated by metal impurities also provide a valuable reference how to select the suitable electrodes for other electroluminescence devices.

4.
Opt Express ; 27(19): 27039-27045, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674572

RESUMO

In this paper, a nematic liquid crystal (NLC)-based tunable terahertz (THz) plasmonic metamaterials (MMs) with large modulation depth (MD) and low insertion loss (IL) is designed and experimentally verified at THz frequencies. The proposed structure includes two-layered MM that is immersed in LC. The metal MM is used directly as electrode. The tunable device with a 46×46 array of sub-wavelength circular air loops was fabricated on a quartz glass substrate, with 2×2 cm2 area and 220 µm thickness. The obtained results show that the amplitude MD and IL for normally incident electromagnetic (EM) waves are about 96% and 1.19 dB at 421.2 GHz, respectively, when the bias voltage applied to the NLC layer varies from 0 to 16 V. Meanwhile, the transmission peak frequency gradually decreases from 421.2 to 381.8 GHz, and the frequency tunability (FT) of the proposed structure is greater than 9.35%. This study provides a potential solution for THz modulators, filters, and switches.

5.
Opt Lett ; 44(21): 5165-5168, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674957

RESUMO

We propose and demonstrate a simple approach for noncontact, three-dimensional, and stable trapping of a single nanoparticle with a super-low incident laser power (0.7 mW) via the single-fiber optical tweezers. We splice a section of single-mode fiber and a section of multimode fiber to construct a Bessel-like beam, which produces narrow output laser beams. We integrate a high-refractive-index glass microsphere on the tip of the multimode fiber to focus the narrow output laser beams. The focused beams provide a nanoscale optical trap for a single nanoparticle (polystyrene sphere, diameter of 200 nm). This optical fiber probe has the advantages of high laser transmission efficiency, high spatial resolution, and minimum joule heating. The proposed approach extends the application potential of fiber-based optical manipulations, such as nanoparticle sorting, single-cell organelle analysis, and bio-sensing.

6.
Opt Lett ; 44(21): 5173-5176, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674959

RESUMO

In this Letter, we propose, to the best of our knowledge, the first in-fiber optofluidic Raman surface-enhanced Raman spectroscopy (SERS) sensor based on a microstructured hollow fiber (MHF) with a suspended core. Taking advantage of the unique internal structure, we immobilize silver nanoparticles with an SERS effect in the MHF by chemical bonding. The Raman signal of the microfluidic sample is excited by the excitation light in the suspended core through an evanescent field. Then the online SERS signal can be coupled back into the core and detected. To demonstrate the feasibility of the device, rhodamine 6G is chosen as the analyte, and high-quality SERS spectra are detected with the limit of detection of 1×10-14 M. Furthermore, an online optofluidic test is conducted on ceftriaxone (C18H18N8O7S3) to examine its capabilities in antibiotic sensing. The results show that the LOD of the samples is 10-6 M. Significantly, this Letter provides an integrated optofluidic in-fiber SERS sensor with a microchannel that can be integrated with chip devices without spatial optical coupling, which has a broad application in medicine and food safety, as well as various aspects of biological in-fiber sensing.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31729841

RESUMO

Dermis-fat composite tissues have been widely used in plastic and reconstructive surgery and were previously constructed using hydrogel-type scaffolds. The constructs can be used for in vitro cosmetic and pharmaceutical testing but are not mechanically strong enough for in vivo applications. In this study, we used heterogeneous (porcine) acellular dermal matrix (PADM) as dermal layer scaffold. PADM was pretreated with the laser micropore technique and then precultured with rat adipose-derived stem cells (rADSCs) in vitro. rADSCs proliferated well on pretreated/unpretreated PADM, showing increased expression of genes associated with inflammatory regulation, proangiogenesis, and stemness, indicating that pretreated/unpretreated PADM both provide a beneficial microenvironment for rADSCs to exert their paracrine function. After in vitro processing, the rADSCs-polyporous PADM and PADM without pretreatments were implanted into the back of rats respectively, followed by adipose tissue transplantation. After implantation, the inflammation induced by pretreated PADM was significantly attenuated and localized compared to the unpretreated group. Moreover, the vascularization was faster, and more adipose tissue was formed in the pretreated group. Sound dermis-fat composite tissue was constructed with sufficient strength, which can potentially be used for actual repair application.

8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(10): 1179-1184, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31771711

RESUMO

OBJECTIVE: Yichang Central People's Hospital is a large prefecture-level tertiary hospital in Hubei Province. Since the late foundation and interdisciplinary characteritics, the department of emergency and critical care medicine faced many difficulties during development. Based on the actual situation of the hospital, leaders of the hospital and two disciplines advocated their core values of "putting patients' interests first and building team spirit". In consideration of the timeliness, multidisciplinary collaboration and importance of critical care, the department of emergency and critical care medicine in Yichang Central People's Hospital of Hubei Province was set up, and an integrated first-aid platform was established. The concept of "5-minute emergency life chain" was proposed, which highlighted the status and role of the department of emergency and critical care medicine in modern medical rescue and modern general hospitals. In the past 5 years, the emergency department and intensive care unit have made rapid development, including successful establishment of national demonstration centers for chest pain and stroke. Quality of the discipline has also been greatly improved, and a new construction path of department of the emergency and critical care medicine has been created.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31774187

RESUMO

CONTEXT: The saline infusion test (SIT) is a common confirmatory test for primary aldosteronism (PA). According to the guideline, a post-infusion plasma aldosterone concentration (PAC) of 5-10 ng/dl is considered indeterminate, and recommendations for diagnostic strategies are currently limited in this situation. OBJECTIVE: To explore whether an addition of the captopril challenge test (CCT) could improve the diagnostic accuracy in patients with indeterminate SIT. METHODS: A total of 280 hypertensive patients with high risk of PA completed this study. Subjects were defined as SIT indeterminate based on their PAC post-SIT. These patients then underwent the CCT where PACs post-CCT >11 ng/dl were considered positive. Using fludrocortisone suppression test (FST) as the reference standard, diagnostic parameters including area under the receiver-operator characteristic curves (AUC), sensitivity and specificity were calculated. RESULTS: There were 65 subjects (23.2%) diagnosed as PA indeterminate after SIT. With the addition of CCT, true positive numbers increased from 134 to 147, and false negative numbers decreased from 27 to 14. Compared to SIT alone, a combination of SIT and CCT showed a higher AUC [0.91(0.87,0.94) vs. 0.87(0.83,0.91), P=0.041] and an increased sensitivity for the diagnosis of PA [0.91(0.86,0.95) vs. 0.83(0.76,0.89), P=0.028], while the specificity remained similar. In the subgroup with indeterminate SIT results, using PAC post-CCT resulted in a 36% higher AUC than using PAC post-SIT alone for the diagnosis of PA. CONCLUSION: For patients under investigation for possible PA who have indeterminate SIT results, an addition of CCT improves the diagnostic accuracy.

10.
11.
Nat Commun ; 10(1): 5348, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767839

RESUMO

There is increasing evidence for a strong inherited genetic basis of susceptibility to acute lymphoblastic leukaemia (ALL) in children. To identify new risk variants for B-cell ALL (B-ALL) we conducted a meta-analysis with four GWAS (genome-wide association studies), totalling 5321 cases and 16,666 controls of European descent. We herein describe novel risk loci for B-ALL at 9q21.31 (rs76925697, P = 2.11 × 10-8), for high-hyperdiploid ALL at 5q31.1 (rs886285, P = 1.56 × 10-8) and 6p21.31 (rs210143 in BAK1, P = 2.21 × 10-8), and ETV6-RUNX1 ALL at 17q21.32 (rs10853104 in IGF2BP1, P = 1.82 × 10-8). Particularly notable are the pleiotropic effects of the BAK1 variant on multiple haematological malignancies and specific effects of IGF2BP1 on ETV6-RUNX1 ALL evidenced by both germline and somatic genomic analyses. Integration of GWAS signals with transcriptomic/epigenomic profiling and 3D chromatin interaction data for these leukaemia risk loci suggests deregulation of B-cell development and the cell cycle as central mechanisms governing genetic susceptibility to ALL.

13.
J Ethnobiol Ethnomed ; 15(1): 56, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775804

RESUMO

BACKGROUND: The Hani people in the Honghe Prefecture of Southeastern Yunnan, China, have practiced terraced rice paddy farming for more than 1300 years. These rice fields, combined with the surrounding forests and water systems, form a special agroecosystem that has attracted both tourists and scientists. For centuries, the local people have traditionally collected wild edible plants (WEP) from the agroecosystem, but this unique traditional practice in this area has never been reported. METHODS: Ethnobotanical fieldwork was conducted in four counties (Yuanyang, Honghe, Jinping, and Lüchun) between 2014 and 2019. Local self-identified Hani people (186) were interviewed, and information concerning local WEP species was obtained, documented, and analyzed. Plant samples and voucher specimens were collected for taxonomic identification. RESULTS: A total of 224 WEP species, belonging to 90 families and 170 genera, were recorded as used by the Hani people in Honghe. The most common WEP parts used include fruits, stems, and leaves, and the most common preparation methods include eating as a potherb (wild vegetable) and eating fresh. Some WEPs, like Phyllanthus emblica and Dioscorea subcalva, have unique preparation methods. The use-value (UV) and frequency of utilization index (FUI) of WEP species were analyzed. The 20 WEP species with the highest UV were noted as particularly important to the Hani people's daily life in Honghe. CONCLUSION: A large majority of these WEP species possess tremendous economic potential for future development. However, the diversity of WEP species, the associated traditional knowledge, and the broader agroecosystem are facing challenges such as biodiversity loss and pollution from chemical pesticides and fertilizers. This study may help local people to recognize the value of local WEP species and associated traditional knowledge, as well as provide ethnobotanical information for the future development of this tourism region.

14.
J Cardiothorac Surg ; 14(1): 206, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775824

RESUMO

BACKGROUND: Acute type A aortic dissection complicated by malperfusion is a life - threatening emergency. The optimal management strategy for malperfusion remains controversial. CASE PRESENTATION: A 46-year-old man presented to another institution with acute type A aortic dissection with abdominal aorta occlusion. Motor and sensory grade of both lower extremities were zero. Immediate antegrade distal perfusion of both lower extremities was achieved, and total arch replacement with left axillo-bifemoral bypass was performed. At the time of discharge, motor and sensory grades of both lower extremities were 2 and 3, respectively. CONCLUSION: This case demonstrates many of the techniques in the management of acute type A aortic dissection with abdominal aorta occlusion. In this case, direct antegrade perfusion of both lower extremities and axillo-bifemoral bypass may be helpful for patients presenting with severe malperfusion of both lower extremities with acute type A aortic dissection.

15.
Nanoscale ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31750494

RESUMO

Implementing the hierarchical structures of non-noble-metal-based electrocatalysts and modulating their composition can help accelerate surface reactions and fulfill the promise of renewable energy devices via water splitting. Herein, molybdenum-based compounds are constructed on activated nickel foam (act-NF) by a one-step hydrothermal growth. The product generated on the act-NF is NixCo1-xMoO4@CoMoO4, with a novel 3D hierarchical heterostructure, wherein the one-dimensional CoMoO4 nanorods are hierarchically integrated with the two-dimensional NixCo1-xMoO4 nanosheets (NCMO@CMO/act-NF). The formation of NixCo1-xMoO4@CoMoO4 attributes to the release and diffusion of Ni2+ from act-NF. Heterogeneous NixCo1-xMoO4@CoMoO4 has compositional differences, and synergistic interaction between cobalt and nickel results in the modulated electronic states. Meanwhile, the hierarchical structure facilitates the exposure of active sites. Combining these two advantages, NCMO@CMO/act-NF presents a low η10 value of 61 and 180 mV in 1.0 M KOH for the HER and OER, respectively, and it shows a low cell voltage of 1.46 V for overall water splitting with robust stability. DFT calculations reveal that Ni doping leads to the charge depletion of Co, which further optimizes the d-band center of metal sites and tunes the adsorption of adsorbates to facilitate the water splitting reaction. Thus, a promising strategy of incorporating the nanostructure design with compositional modulation is presented to develop functional materials for energy conversion.

16.
Nanotechnology ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31751955

RESUMO

Since the first report on solid-state perovskite solar cell (PSC) with ~10% power conversion efficiency (PCE) and 500 h-stability in 2012, tremendous efforts have been being devoted to develop PSCs with higher PCE, longer stability and recycling hazardous lead waste. As a result, PCE over 23% was recorded in 2018 and stability over 10,000 h was reported. Beyond photovoltaics, lead halide perovskite materials demonstrated superb properties when they were applied to flat-panel X-ray detector and non-volatile resistive switching memory. In this review, progresses of lead halide perovskite in photovoltaics, X-ray imaging and memristor are investigated. Pb-based PSCs and non-Pb-based PSCs are compared, where technologies of non-Pb-based PSCs are not matured for commercialization. Pb-based PSCs were found to be highly suitable for both terrestrial and space photovoltaics. Higher sensitivity under low dose rate observed from lead halide perovskite suggests a bright future of perovskite X-ray imaging system. Moreover, high on/off ratio and low energy consumption observed in resistive switching enable perovskite to be promising candidate for high density memristor.

17.
J Cell Mol Med ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31755246

RESUMO

Emerging evidence illustrates the critical roles of long non-coding RNAs (lncRNAs) in the diabetes. However, the deepgoing regulation of lncRNA PVT1 in the diabetic cataract (DC) is still unclear. Here, present research investigates the pathologic roles and underlying mechanism by which lncRNA PVT1 regulates the DC pathogenesis. Human lens epithelial (HLE) B-3 cells were induced by the high glucose (HG) to simulate the DC microenvironment models. Results revealed that lncRNA PVT1 expression was up-regulated in the HG-induced HLE B-3 cells as compared to the normal glucose group. Transcription factor SP1 could bind with the promoter region of PVT1 and activate its transcription. Functionally, PVT1 knock-down could repress the proliferation and promote the apoptosis of HLE B-3 cells. Mechanistically, PVT1 acted as the 'miRNA sponge' to target miR-214-3p/MMP2 axis. This finding revealed a novel insight of lncRNA PVT1 for the DC pathogenesis, providing an inspiration for the DC mechanism.

18.
Exp Cell Res ; 385(2): 111691, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678170

RESUMO

Rafoxanide is commonly used as anti-helminthic medicine in veterinary medicine, a main compound of salicylanilide. Previous studies have reported that rafoxanide, as an inhibitor of BRAF V600E mutant protein, inhibits the growth of colorectal cancer, multiple myeloma, and skin cancer. However, its therapeutic effect on gastric cancer (GC) and the potential mechanism has not been investigated. Here, we have found that rafoxanide inhibited the proliferation of GC cells in vitro, arrested the cell cycle in the G0/G1 phase, and promoted apoptosis and autophagy in GC cells. Treatment with specific autophagy inhibitor 3-methyladenine drastically inhibited the apoptotic cell death effect by suppressing the switch from autophagy to apoptosis. Mechanistically, we found that rafoxanide inhibited the growth of GC cells in vitro by inhibiting the activity of the PI3K/Akt/mTOR signaling pathway. This process induced autophagy, which essentially resulted in the apoptosis of GC cells. Results from subcutaneous implanted tumor models in nude mice also indicated that rafoxanide inhibited the growth of GC cells in vivo. Taken together, our findings revealed that rafoxanide inhibited the growth of GC cells both in vitro and vivo, indicating a potential drug candidate for the treatment of GC.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31713966

RESUMO

Lithium-sulfur (Li-S) batteries are well known as one of the most promising next-generation batteries owing to its ultra-high theoretical energy density and abundant sulfur resources. During the past 20 years, various sulfur materials have been reported. As the representative of molecular scale sulfur composite cathode, sulfurized pyrolyzed poly(acrylonitrile) (S@pPAN) exhibits several competitive advantages in terms of electrochemical behaviors. Currently, S@pPAN attracts increasing attentions although it was first reported in 2002. In this review, we firstly summarize its molecular model, which benefits to elucidate the correlation between structure property and exceptional electrochemical performance. Secondly, we classify the modification strategies into three parts, including material improvement, binder and electrolyte screening. In consideration of promising future of S@pPAN, several research and development directions are also suggested.

20.
Blood ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31697823

RESUMO

To study the mechanisms of relapse in acute lymphoblastic leukemia (ALL), we performed whole-genome sequencing of 103 diagnosis-relapse-germline trios and ultra-deep sequencing of 208 serial samples in 16 patients. Relapse-specific somatic alterations were enriched in 12 genes (NR3C1, NR3C2, TP53, NT5C2, FPGS, CREBBP, MSH2, MSH6, PMS2, WHSC1, PRPS1, and PRPS2) involved in drug response. Their prevalence was 17% in very early relapse (<9 months from diagnosis), 65% in early relapse (9-36 months), and 32% in late relapse (>36 months) groups. Convergent evolution, where multiple subclones harbor mutations in the same drug resistance gene, was observed in six relapses and confirmed by single-cell sequencing in one case. Mathematical modeling and mutational signature analysis indicated that early relapse resistance acquisition was frequently two-step process where a persistent clone survived initial therapy, and later acquired bona fide resistance mutations during therapy. In contrast, very early relapses arose from pre-existing resistant clone(s). Two novel relapse-specific mutational signatures, one of which was caused by thiopurine treatment based on in vitro drug exposure experiments, were identified in early and late relapses but were absent from 2,540 pan-cancer diagnosis samples and 129 non-ALL relapses. The novel signatures were detected in 27% of relapsed ALLs and were responsible for 46% of acquired resistance mutations in NT5C2, PRPS1, NR3C1, and TP53. These results suggest that chemotherapy-induced drug resistance mutations facilitate a subset of pediatric ALL relapses.

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