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1.
J Nanosci Nanotechnol ; 20(4): 2578-2583, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492279

RESUMO

Quaternary colloidal CuIn0.7Ga0.3S2 nanocrystals were synthesized by hot injection method using oleylamine as single solvent. The structure, morphology and optical absorption properties of assynthesized CuIn0.7Ga0.3S2 nanocrystals were characterized in detail using X-ray powder diffraction, transmission electron microscopy and UV-vis spectrometry. The as-fabricated CIGSSe thin film was obtained by spin-casting as-synthesized colloidal CuIn0.7Ga0.3S2 nanocrystals after selenization. The classical pn heterojunction CIGSSe/CdS thin film solar cells displayed the 6.18% power conversion efficiency under AM1.5G illumination.

2.
Sci Total Environ ; 698: 133860, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514029

RESUMO

The correlation between long-term exposure to SRF-EMR and the decline in male fertility is gradually receiving increasing attention from the medical society. While male reproductive organs are often exposed to SRF-EMR, little is currently known about the direct effects of long-term SRF-EMR exposure on the testes and its involvement in the suppression of male reproductive potential. The present study was designed to investigate this issue by using 4G SRF-EMR in rats. A unique exposure model using a 4G smartphone achieved localized exposure to the scrotum of the rats for 6 h each day (the smartphone was kept on active talk mode and received an external call for 1 min over 10 min intervals). Results showed that SRF-EMR exposure for 150 days decreased sperm quality and pup weight, accompanied by testicular injury. However, these adverse effects were not evident in rats exposed to SRF-EMR for 50 days or 100 days. Sequencing analysis and western blotting suggested Spock3 overexpression in the testes of rats exposed to SRF-EMR for 150 days. Inhibition of Spock3 overexpression improved sperm quality decline and alleviated testicular injury and BTB disorder in the exposed rats. Additionally, SRF-EMR exposure suppressed MMP2 activity, while increasing the activity of the MMP14-Spock3 complexes and decreasing MMP14-MMP2 complexes; these results were reversed by Spock3 inhibition. Thus, long-term exposure to 4G SRF-EMR diminished male fertility by directly disrupting the Spock3-MMP2-BTB axis in the testes of adult rats. To our knowledge, this is the first study to show direct toxicity of SRF-EMR on the testes emerging after long-term exposure.

3.
Food Funct ; 10(11): 7588-7598, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31687714

RESUMO

Increasing evidence points to the effect of the gut microbiota on central nervous system functions. Supplementation of certain microbial strains has been demonstrated to alleviate depressive behaviors and neurological abnormalities. This study took the approach to screen for an anti-depressive Bifidobacterium longum strain from fourteen candidates and systematically verified its effect in a chronic stress-induced depression mice model. B. longum subsp. infantis strain CCFM687 could significantly enhance the biosynthesis of 5-hydroxytryptamine (5-HTP) in vitro in RIN14B cells through up-regulation of the Tph1 gene expression. Administration of CCFM687 in mice significantly improved the scores in behavioral tests and increased the level of 5-HTP and serotonin (5-HT) in the prefrontal cortex (PFC) of the brain. The brain-derived neurotrophic factor (BDNF) in the PFC was also increased, possibly through the 5-HT1A-CREB-BDNF pathway. In addition, CCFM687 alleviated the hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis response and accordingly reversed the peripheral inflammation status. Moreover, the stress-induced structural and functional dysbiosis of the gut microbiome was improved by CCFM687, through increased alpha diversity and abundance of butyrate-producing bacteria, in conjunction with inhibition of pathogenic gene expression. In summary, these results indicate that supplementation of B. longum subsp. infantis strain CCFM687 may prevent the onset of depression from chronic stress, and RIN14B could serve as an efficient cell model for rapid screening of anti-depressive probiotics.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31714795

RESUMO

Mitochondria have an essential function in cell survival due to their role in bioenergetics, reactive oxygen species generation, calcium buffering, and other metabolic activities. Mitochondrial dysfunctions are commonly found in neurodegenerative diseases (NDs), and diabetes is a risk factor for NDs. However, the role of mitochondria in diabetic neurodegeneration is still unclear. In the current study, we reviewed the latest evidence on the role of mitochondrial dysfunctions in the development of diabetes-related NDs and the underlying molecular mechanisms. Hypoglycemic agents, especially metformin, have been proved to have neuroprotective effects in the treatment of diabetes, in which mitochondria could act as one of the underlying mechanisms. Other hypoglycemic agents, including thiazolidinedione (TZDs), dipeptidyl peptidase 4 (DPP-4) inhibitors, and glucagon-like peptide 1 (GLP-1) receptor agonists, have gained more attention due to their beneficial effects on NDs, presumably by improving mitochondrial function. Our review highlighted the notion that mitochondria could be a promising therapeutic target in the treatment of NDs in patients with diabetes.

5.
Plasmid ; 106: 102441, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31676335

RESUMO

Synthetic promoters (SPs) have many advantages over their natural counterparts, especially with regard to transcriptional activity and tissue specificity. Here, we report a new strategy to construct SPs for efficient and muscle-specific gene expression. First, 19 nucleic acid motifs classified to 3 kinds of transcriptional regulatory elements were rationally selected. A recombinant promoter library was constructed by randomly assembling these motifs. Second, the transcriptional activities of ~1200 SPs were screened by intramuscular expression of several reporter genes in different cell lines for activity higher than that of the cytomegalovirus (CMV) promoter, with SP-301 finally identified as the strongest. A single intramuscular injection of mice with an SP-301 plasmid expressing mouse growth hormone releasing hormone accelerated mouse growth significantly over 24 days. Third, the muscle specificity of SP-301 was confirmed in transgenic mice. Finally, in comparison with the CMV promoter, SP-301 accelerated translocation and increased the level of plasmid in the nuclei of myoblast cells to a greater extent than in non-muscle cells. Altogether, the study has provided a more rational strategy to construct efficient and tissue-specific promoters, with the promoter SP-301 exhibiting promising potential for establishing an intramuscular gene expression system for therapeutic applications.

6.
Sci Rep ; 9(1): 15744, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673091

RESUMO

Endoscopic grading of gastroesophageal flap valve (GEFV) is simple and reproducible and offers useful information for reflux activity. To investigate the potential correlation between GEFV grading and reflux finding score (RFS) in patients with laryngopharyngeal reflux disease (LPRD), 225 consecutive Patients with suspected LPRD who underwent both routine upper gastrointestinal endoscopy and laryngoscope were enrolled in our study. Patients with a RFS of more than 7 were diagnosed with LPRD. The GEFV was graded as I through IV according to Hill's classification and was classified into two groups: normal GEFV group (grades I and II) and the abnormal GEFV group (grades III and IV). The percent of GEFV grades I to IV was 39.1%, 39.1%, 12.4%, and 9.3%, respectively. Age was significantly related to an abnormal GEFV (p = 0.002). Gender, BMI, smoke and alcohol were not related to GEFV grade. Fifty-one patients (22.67%) had positive RFS. Reflux finding scores were higher in GEFV grades III and IV than I and II (p < 0.05). Endoscopic grading of GEFV is well correlated with reflux finding score in patients with LPRD. This is a simple and useful technique that provides valuable diagnostic information of LPRD.

7.
Medicine (Baltimore) ; 98(44): e17823, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689869

RESUMO

BACKGROUNDS: Hand fractures are the second most common upper-extremity fractures. The standard X-ray has shortcomings, such as exposure to radiation. Ultrasound has been reported as an alternative method of detecting hand fractures. In this study, we used meta-analysis to assess the diagnostic value of ultrasound for hand fractures. METHODS: Web of Science, PubMed, Embase, and Cochrane Library databases were searched for relative citations up to June 2019. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the summary receiver operating characteristic curve (AUC), and summary receiver operating characteristic (SROC) curve were estimated. RESULTS: Seven studies including 842 participants (845 examined hands) met our inclusion criteria. The pooled sensitivity, specificity, PLR, and NLR of ultrasound for detecting hand fractures were 91%, 96%, 20.66, and 0.09, respectively. The pooled DOR was 231.17, indicating a very powerful diagnostic ability of ultrasound. Meta-regression showed that there was no heterogeneity with respect to age, cut-off, the performer of the ultrasound, and the types of hand fractures. CONCLUSIONS: Our results showed that ultrasound had an excellent diagnostic value for hand fractures. In clinic, we proposed using ultrasound as a first-line and radiation-free modality in detecting hand fractures, including phalanx and metacarpal fractures.


Assuntos
Falanges dos Dedos da Mão/diagnóstico por imagem , Falanges dos Dedos da Mão/lesões , Fraturas Ósseas/diagnóstico por imagem , Ossos Metacarpais/diagnóstico por imagem , Ossos Metacarpais/lesões , Humanos , Ultrassonografia
8.
Pharmacology ; : 1-9, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31722364

RESUMO

The chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is affected by a variety of factors, including environmental, physical, and chemical factors and growth factors, and traditional Chinese medicine (TCM) preparations can further influence this process. In this study, the effects of different concentrations of Yam-containing serum of rabbits on BMSC proliferation and chondrogenic differentiation were investigated, as were the underlying molecular mechanisms. The growth and proliferation of BMSCs were significantly enhanced upon treatment with Yam-containing serum. Under both monolayer and micromass culture conditions, Yam-containing serum promoted the differentiation of BMSCs into chondrocytes. Toluidine blue staining results revealed that chondrocyte differentiation in the group treated by Yam-containing serum was significantly more pronounced than in the control group. Glycosaminoglycan levels, as measured by 1,2-dimethylmethylene blue (DMMB) detection, were significantly higher in cells of the Yam-containing group relative to the control group. This is the first study to our knowledge that demonstrates that Yam-containing serum can promote BMSC proliferation and chondrogenic differentiation. This study therefore lays an experimental groundwork for further application of TCM as a means of treating degenerative cartilage diseases and provides an experimental and theoretical basis for the combination of TCM and stem cells for the treatment of such diseases.

9.
Pharmacology ; : 1-9, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694038

RESUMO

OBJECTIVES: (1) To detect the whether the effects of simulated ischemia on INa of rat left ventricular myocytes in a time-dependent manner and the effects of atorvastatin on ischemia INa; (2) To investigate the effects of atorvastatin on INa of rat-simulated ischemia/reperfusion (I/R) ventricular cells. MATERIALS AND METHODS: Ventricular cells were enzymatically isolated by Langendorff perfusion system. Whole-cell patch clamp was applied to detect INa level. Some elements of extracellular fluid were hanged to simulate the status of normal, I and R condition. Then the effects of atorvastatin on INa were observed. RESULTS: (1) During simulated reperfusion, INa decreased and atorvastatin further suppressed the reduction degree. (2) At test potential -40 mV, no difference was detected among peak INa amplitude of ischemia for 20 min, reperfusion phase 3/5/7/9 min in continuous ischemia (I) group (p = 0.275). In I/R group, peak INa amplitude continuously decreased at 3 min (p = 0.005) and 9 min (p = 0.041). In atorvastatin intervention + I/R (Statin + I/R) group, peak INa amplitude at reperfusion 3 min decreased compared with ischemia phase (p = 0.000), while no significant difference was detected between 3 and 9 min (p = 0.858). The differences were significant at the same time point between groups. At reperfusion 3/5/7/9 min, peak INa of the I/R group was lower than the ischemia group (all p = 0.000), same as the Statin + I/R group (p = 0.000, p = 0.003, p = 0.006, and p = 0.001). Peak INa of the Statin + I/R group was higher than the I/R group at the same time point (p = 0.011, p = 0.033, p = 0.003, p = 0.003). There was no change in the I group during reperfusion phase (p > 0.05). In I/R group, V1/2 (mV) shifted from -58.87 ± 3.36 to -54.33 ± 2.40, k (mV) shifted from 1.25 ± 0.59 to 1.91 ± 0.84 (p < 0.05). In the Statin + I/R group, V1/2 (mV) increased from -57.80 ± 2.97 to -52.76 ± 3.14 (p < 0.01), no change was observed in k (p > 0.05). CONCLUSIONS: (1) In the status of reperfusion, INa decreased more than that in the status of ischemia. (2) Atorvastatin protected the cells from reduction of INa during long-time simulated (>15 min) I/R. (3) Overall, atorvastatin affected INa of the normal, simulated ischemic/reperfusion cell in rat left ventricle by blocking sodium channel -directly.

10.
Molecules ; 24(22)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703373

RESUMO

In this work, a series of benzylsulfone coumarin derivatives 5a-5o were synthesized and characterized. Kinase inhibitory activity assay indicated that most of the compounds showed considerable activity against PI3K. Anti-tumor activity studies of the active compounds were also carried out in vitro on the Hela, HepG2, H1299, HCT-116, and MCF-7 tumor cell lines by MTS assay. The structure-activity relationships (SARs) of these compounds were analyzed in detail. Compound 5h exhibited the most potent activities against the mentioned cell lines with IC50 values ranging from 18.12 to 32.60 µM, followed by 5m with IC50 values of 29.30-42.14 µM. Furthermore, 5h and 5m clearly retarded the migration of Hela cells in vitro. Next, an in silico molecular docking study was conducted to evaluate the binding models of 5h and 5m towards PI3Kα and PI3Kß. Collectively, the above findings suggested that compounds 5h and 5m might be promising PI3K inhibitors deserving further investigation for cancer treatment.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31756352

RESUMO

BACKGROUND: Keratinocytes can function as innate immune cells under oxidative stress and aggravate cutaneous T cell response that undermines melanocytes in vitiligo. The NLR family pyrin domain containing 3 (NLRP3) inflammasome is a regulator of innate immunity that exists in keratinocytes. However, the role of NLRP3 inflammasome in the pathogenesis of vitiligo has not been investigated. OBJECTIVE: We sought to explicate the contribution of activated NLRP3 inflammasome in keratinocytes to the autoimmune response in vitiligo. METHODS: Perilesional and serum samples from vitiligo patients were collected to examine the status of NLRP3 inflammasome in vitiligo. Cultured keratinocytes were treated with H2O2 to investigate the mechanism for NLRP3 inflammasome activation under oxidative stress. Peripheral blood T cells were extracted from vitiligo patients to explore the influence of NLRP3 inflammasome on T cell response in vitiligo. RESULTS: The expressions of NLRP3 and downstream cytokine IL-1ß were consistently elevated in perilesional keratinocytes of vitiligo. Notably, serum IL-1ß level was increased in vitiligo patients, correlated with disease activity and severity and decreased after effective therapy. Furthermore, oxidative stress promoted NLRP3 inflammasome activation in keratinocytes via transient receptor potential cation channel subfamily M member 2 (TRPM2), a redox-sensitive cation channel, which was dependent on TRPM2-mediated calcium influx. More importantly, blocking TRPM2-induced NLRP3 inflammasome activation in keratinocytes impaired the chemotaxis for CD8+ T cells and inhibited the production of cytokines in T cells in vitiligo. CONCLUSION: Oxidative stress-induced NLRP3 inflammasome activation in keratinocytes promotes cutaneous T cell response, which could be targeted for the treatment of vitiligo.

12.
Int J Pharm ; : 118718, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756441

RESUMO

Intestinal mono-carboxylate transporter 1 (MCT1) plays an important role in the oral absorption of short-chain fatty acids that were used as oxidative metabolite. However, the prodrug strategy targeting intestinal MCT1 for oral delivery is rarely exploited. The oral bioavailability of Gemcitabine (Gem) is low mainly due to its poor intestinal permeability and rapid metabolism. Herein, a facile di-acid mono-amidation strategy was firstly developed to target MCT1 for oral chemotherapy. The N4-amino group of Gem is mono-amidated with di-acids containing different carbon chain lengths, which could recognize intestinal MCT1 and are bio-activated at physiological pH independent of the hydrolysis enzymes. The adipic acid-Gem shows higher MCT1 affinity, better gastrointestinal tract stability (3-fold), improved oral bioavailability (8.8-fold), and less gastrointestinal toxicity in comparison to Gem. Moreover the bio-activation rate of the prodrugs decreases with the increased fatty acid chain length of the linkage under physiological conditions. In summary, we present the first evidence that MCT1 could act as a new target for oral prodrug delivery, and that the linkage could modify the bio-activation rate for achieving optimal oral bioavailability. Our findings provide novel knowledge to rationally design intestinal transporter-targeting oral carrier prodrug.

13.
J Chem Phys ; 151(19): 194506, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31757144

RESUMO

A survey of published literature reveals a difference in the density of amorphous and crystalline solids (organic and inorganic) on the order of 10%-15%, whereas for metallic alloys, it is found to be typically less than 5%. Standard geometric models of atomic packing can account for the polymeric and inorganic glasses without requiring changes in interatomic separations (bond lengths). By contrast, the relatively small difference in density between crystalline and glassy metals (and metallic alloys) implies variations in interatomic separations due to merging orbitals giving rise to reduced atomic volumes. To test this hypothesis, quantum density functional theory computations were carried out on ordered and irregular clusters of aluminum. The results point to decreasing interatomic distances with decreasing coordination, from which one can deduce that the geometrical method of random hard sphere packing significantly underestimates the densities of amorphous metallic alloys.

14.
Int J Biol Macromol ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31758995

RESUMO

In order to improve the hydrophilicity and immune activity of the polysaccharide from Dendrobium nobile Lindl., non-thermalplasma was used to treat the polysaccharide. It was found that the hydrophilicity of the polysaccharide plasma-treated was significantly enhanced. Infrared spectra showed that the content of -OH in the molecule increased significantly, and the monosaccharide ring changed from ß-pyran sugar to ß-furan sugar. The detection of SEM, AFM and TEM showed that the degree of cross-linking of surface molecules increased, and the arrangement of the polysaccharide was more compact and orderly. In vitro cell tests showed that the polysaccharide plasma-treated significantly improve the phagocytosis ability of RAW264.7, and promote the secretion of cytokines TNF-α, IL-6, IL-1. However, the cell proliferation test indicated that the polysaccharide did not increase the concentration of cytokines by promoting cell proliferation. RT-PCR showed that the polysaccharide plasma-treated could promote the expression of IL-1ß at the transcriptional level. These results showed that non-thermalplasma treatment can effectively enhance the hydrophilicity of the polysaccharide and enhance its immune activity in vitro. Therefore, it can be inferred that the non-thermal plasma technology can be applied to the modification of active polysaccharides and will promote active polysaccharides to work better.

15.
Biochem Pharmacol ; 171: 113680, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669234

RESUMO

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide and tends to have drug resistance. Delicaflavone (DLF), a novel anticancer agent of biflavonoid from Selaginella doederleinii Hieron, showed strong anti-CRC activities, which has not yet been reported. In this study, we investigated the effects and possible anti-CRC mechanism of DLF in vitro and in vivo. It was shown that DLF significantly inhibited the cells viability and induced G2/M phase arrest, apoptosis, the loss of mitochondrial membrane potential (Δψm), generation of ROS and increase of intracellular Ca2+ in HT29 and HCT116 cells by MTT assay, TEM, flow cytometry and inverted fluorescence microscope. Western blot and qPCR assays results further confirmed DLF induced caspase-dependent apoptosis and inhibited PI3K/AKT/mTOR and Ras/MEK/Erk signaling pathways in CRC cells. Meanwhile, DLF significantly suppressed the tumor growth via activation of Caspase-9 and Caspase-3 protein and decrease of ki67 and CD34 protein without apparent side effects in vivo. In summary, these results indicated DLF induced ROS-mediated cell cycle arrest and apoptosis through ER stress and mitochondrial pathway accompanying with the inhibition of PI3K/AKT/mTOR and Ras/MEK/Erk signaling cascade. Thus DLF could be a potential therapeutic agent for CRC.

16.
Trends Microbiol ; 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31744664

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) dramatically affects the thymus and its ability to carry out its normal functions. In particular, infection incapacitates PRRSV-susceptible CD14pos antigen-presenting cells (APCs) in the thymus and throughout the body. PRRSV-induced autophagy in thymic epithelial cells modulates the development of T cells, and PRRSV-induced apoptosis in CD4posCD8pos thymocytes modulates cellular immunity against PRRSV and other pathogens. Pigs are less able to resist and/or eliminate secondary infectious agents due the effect of PRRSV on the thymus, and this susceptibility phenomenon is long recognized as a primary characteristic of PRRSV infection.

17.
Clin Cancer Res ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744831

RESUMO

PURPOSE: DNA mismatch repair defects (MMRd) and tumor hypermutation are rare and under-characterized in metastatic prostate cancer. Furthermore, since hypermutated MMRd prostate cancers can respond to immune checkpoint inhibitors, there is an urgent need for practical detection tools. EXPERIMENTAL DESIGN: We analyzed plasma cell-free DNA targeted sequencing data from 433 metastatic prostate cancer patients with circulating tumor DNA (ctDNA) purity ≥2%. Samples with somatic hypermutation were subjected to 185× whole exome sequencing and capture of mismatch repair gene introns. Archival tissue was analyzed with targeted sequencing and immunohistochemistry. RESULTS: 16 patients (3.7%) had somatic hypermutation with MMRd etiology, evidenced by deleterious alterations in MSH2, MSH6, or MLH1, microsatellite instability, and characteristic trinucleotide signatures. CtDNA was concordant with mismatch repair protein immunohistochemistry and DNA sequencing of tumor tissue. Tumor suppressors such as PTEN, RB1, and TP53 were inactivated by mutation rather than copy number loss. Hotspot mutations in oncogenes such as AKT1, PIK3CA and CTNNB1 were common, and the AR ligand binding domain was mutated in 9/16 patients. We observed high intra-patient clonal diversity, evidenced by subclonal driver mutations and shifts in mutation allele frequency over time. Patients with hypermutation and MMRd etiology in ctDNA had a poor response to Androgen Receptor inhibition and inferior survival compared to a control cohort. CONCLUSIONS: Hypermutated MMRd metastatic prostate cancer is associated with oncogene activation and subclonal diversity, which may contribute to a clinically aggressive disposition in selected patients. In patients with detectable ctDNA, cell-free DNA sequencing is a practical tool to prioritize this subtype for immunotherapy.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117671, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31670043

RESUMO

In this paper, a simple, economical, and green strategy is developed for producing nitrogen doped graphene quantum dots (N-GQDs) with multicolor light emission by hydrothermal treatment of Passiflora edulia Sims. The synthesized N-GQDs exhibit ideal ionic stability, hydrophilicity and anti-photobcleaching properties, and the quantum yield reaches up to about 29%. Because of with the fluorescence quenching effect, the achieved N-GQDs allow to detect Ag+ in a linear range of 10 nM-160 µM, and the limit of detection is calculated to be 1.2 nM according to the S/N of 3. Noteworthy, N-GQDs with blue, green and yellow light emissions are demonstrated via regulating the reaction time and temperature, implying a promising fluorescence adjustability. Furthermore, the N-GQDs-based fluorescent probe exhibits low cytotoxicity and favorable biocompatibility. Depending on the superior properties, our N-GQDs are applied in fluorescent ink and multicolor cell imaging. Eventually, the developed sensor is highly selective and accurate for Ag+ analysis in real water, which demonstrates the promising practical use in environmental determination and/or biomedical engineering.

19.
Chemistry ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674074

RESUMO

The search for structurally simple chromophores with superior fluorescence brightness and wide range of solvent compatibility is highly desirable. Herein, we present a new type of single benzene-based solvatochromic chromophore ( 5 ) with a symmetric bifunctional structure, where the azetidine and ethoxy-carbonyl serve as the electron donating and electron withdrawing groups, respectively. This chromophore exhibits an extraordinary wide range of solvent compatibility and preserves excellent fluorescence quantum yields from non-polar n -hexane to polar methanol and even in water. Unusually, the symmetric structure 5 shows a distinct color change from bright green to red along increasing solvent polarity and possesses large Stokes shifts (132-207 nm) in the tested solvents. Moreover, this single benzene-based chromophore displays good photochemical stability in both solution and solid state, and even exhibits reversible mechanochromic luminescence.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31729145

RESUMO

Constructing artificial solid electrolyte interface (SEI) is a highly effective approach to overcome the poor reversibility of lithium (Li) metal anodes. Herein, an adhesive and self-healable supramolecular copolymer, comprising of pendant poly(ethylene oxide) (PEO) segments and ureido-pyrimidinone (UPy) quadruple hydrogen bonding moieties, is developed as a new protection layer of Li anode by a simple drop-coating. The protection performance of in-situ formed LiPEO-UPy SEI layer is significantly enhanced owing to the strong binding and improved stability arising from a spontaneous reaction between UPy groups with Li metal. Remarkably, an ultrathin (~70 nm) LiPEO-UPy layer can contribute to stable and dendrite-free cycling at a high areal capacity of 10 mAh cm-2 at 5 mA cm-2 for 1000 h. Furthermore, the full cell with high utilization of Li shows a much enhanced cycle life. This facile coating together with the promising electrochemical performance offers a new strategy for the development of dendrite-free metal anodes.

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