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1.
Oncogene ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754213

RESUMO

EGFR-mutant non-small-cell lung cancer (NSCLC) patients inevitably develop drug resistance when treated with EGFR tyrosine kinase inhibitors (TKIs). Systematic genetic analysis is important to understand drug-resistant mechanisms; however, the clinical significance of co-occurring genetic alterations at baseline, co-acquired mutations at progressive disease (PD), and the clonal evolution remain underinvestigated. We performed targeted sequencing of pre-treatment and PD tumor samples from 54 EGFR-mutant NSCLC patients. Ten additional patients were sequenced using whole-exome sequencing to infer the clonal evolution patterns. We observed a domain-dependent effect of PIK3CA mutation at baseline on patient progression-free survival (PFS). In addition, at baseline, 9q34.3/19p13.3 (NOTCH1/STK11/GNA11) showed a co-deletion pattern, which was associated with a significantly worse PFS (p = 0.00079). T790M-postive patients with other concurrent acquired oncogenic mutations had a significantly shorter PFS (p = 0.005). Besides acquired T790M mutation, chromosomal instability (CIN) related genes, including AURKA and TP53 alterations, were the most frequently acquired events. CIN significantly increased during TKI treatment in T790M-negative patients and is a candidate resistance mechanism to the first-generation TKIs. Clonal evolution analyses suggest that the composition and relationship among resistant subclones, particularly relationship with T790M subclone, affect patients' outcomes. Overall, our findings of novel co-occurring alterations and clonal evolution patterns can be served as predictive biomarkers to stratify patients and help to better understand the drug-resistant mechanism to TKIs.

2.
World J Microbiol Biotechnol ; 35(12): 180, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31728755

RESUMO

Derived from RNA, 5'-ribonucleotides, especially Inosine-5'-monophosphate (IMP) and guanosine-5'-monophosphate (GMP), can enhance the umami taste of soy sauce. In this study, the RNA content of three different salt-tolerant yeasts was examined. The most valuable strain was subjected to atmospheric and room-temperature plasma (ARTP) mutagenesis, which improved its RNA content by 160.54%. Regular fermentation with RNA-enhanced strain failed to increase the amount of 5'-ribonucleotides in the soy sauce due to hydrolysis by phosphatase. A two-stage fermentation strategy was then carried out. Aroma compounds were mainly synthesized in the first stage, and RNA-enriched biomass was massively produced in the second stage followed by heat treatment to inactivate phosphatase. After the proposed strategy was applied, IMP and GMP in the soy sauce reached 68.54 and 89.37 mg/L, respectively. Moreover, the amounts of key aroma compounds and organic acids significantly increased. Results may provide new insights for improving the quality of soy sauce through microorganism breeding and fermentation control.

3.
Clin Lung Cancer ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31761448

RESUMO

BACKGROUND: Neurotrophin receptor kinase (NTRK) gene fusions (NTRK+) are rare but actionable oncogenic drivers present in a wide variety of solid tumors. However, the clinicopathologic characteristics of NTRK1 fusion-positive non-small-cell lung cancer are largely unknown. MATERIALS AND METHODS: Lung cancer tissue specimens and/or circulating cell-free DNA from patients with lung cancer who had undergone molecular profiling at a Clinical Laboratory Improvement Amendments (CLIA)-certified genomics laboratory in China were retrospectively reviewed. The laboratory performed NTRK1 fusion detection using hybridization-based targeted next-generation sequencing. The patients' clinical characteristics and treatment history were retrieved from the database for further evaluation. RESULTS: A total of 21,155 Chinese lung cancer cases had undergone molecular profiling from April 2016 to March 2019, including 13,630 adenocarcinoma cases. Of these cases, 12 were positive for NTRK1 fusion, including 10 cases of adenocarcinoma (0.073%), 1 primary sarcomatoid carcinoma, and 1 with an unknown histologic classification. Seven fusion partners (CD74, interferon regulatory factor 2 binding protein 2 [IRF2BP2], lamin A/C [LMNA], PHD finger protein 20 [PHF20], sequestosome 1 [SQSTM1], tropomyosin 3 [TPM3], TPR) were identified. Additionally, 1 unique rearrangement occurred upstream of the transcription start site of BCL9 fused to exon 12 of NTRK1 (intragenic region, BCL9-NTRK1). Of the 12 cases of NTRK1+ lung cancer, 6 had had concurrent activating EGFR mutations and/or had received previous treatment with EGFR tyrosine kinase inhibitors (TKIs), with 2 having concurrent EGFR T790M and 1 additional EGFR C797S. CONCLUSIONS: NTRK1+ lung cancer cases are extremely rare with multiple fusion partners. Additionally, emergence of NTRK1+ fusion might act as a resistance mechanism to EGFR TKIs. When performing comprehensive analysis of acquired resistance to EGFR TKIs, the ability to detect NTRK1 fusions will be important.

4.
Org Lett ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755725

RESUMO

Pd-catalyzed regio- and enantioselective allylic etherification of vinylethylene carbonates (VECs) with diols has been developed. By using cooperative catalysts of the chiral palladium complex and triethylborane in mild conditions, the process gave monoetherified and bisetherified polyglycol derivatives with tetrasubstituted stereocenters in high yields with complete regioselectivities and high levels of enantio- and diastereoselectivities.

5.
Fitoterapia ; 139: 104418, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31704262

RESUMO

A new isoiphionane sesquiterpene, named (3S, 5S, 7S, 10R)-3, 11-dihydroxyisoiphion-4-one (1), two new phloroglucinol glycosides, named eucalglobuside A (2) and eucalglobuside B (3), along with 15 known compounds were isolated from the leaves of Eucalyptus globulus. Their structures were elucidated based on extensive spectroscopic analysis and in comparison with literature data. The absolute configuration of compound 1 was determined by ECD calculation. All isolates were evaluated their inhibitory activities against the mushroom tyrosinase. As a result, three sesquiterpenoids, 1, 5ß, 11-dihydroxy-iphionan-4-one (5), and (-)-globulol (8), exhibited the most potent activities with IC50 values of 14.17 µM, 10.08 µM and 9.79 µM, respectively.

6.
J Med Food ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31770044

RESUMO

Polysaccharide from Ma-chi-xian (Portulacae oleracea L., POLP) was prepared and the therapeutic effect on dextran sodium sulfate-induced colitis mice was investigated in this study. The results of clinical activity score and H&E staining confirmed the therapeutic effect of POLP. POLP could diminished the symptoms of colitis and improve colon histopathological structure of the colitis mice. The expression levels of four cytokines were determined. The concentrations of PGE2 and IL-6 were downregulated by POLP treatment. The COX-2 protein expression levels and the STAT3 phosphorylation levels were detected. The results showed that these two protein levels were all increased in colitis and decreased after POLP treatment, indicating that these two proteins were closely related with the protective effect of POLP. Because the synthesis of PGE2 is catalyzed by COX-2 and phosphorylation of STAT3 can induce the expression of COX-2, it was concluded that STAT3 was a key protein related to the POLP exerting its activity in colitis.

7.
Oncogene ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636388

RESUMO

Intratumoral heterogeneity in bladder cancer is a barrier to accurate molecular sub-classification and treatment efficacy. However, individual cellular and mechanistic contributions to tumor heterogeneity are controversial. We examined potential mechanisms of FOXA1 and PTEN inactivation in bladder cancer and their contribution to tumor heterogeneity. These analyses were complemented with inactivation of FOXA1 and PTEN in intermediate and luminal mouse urothelium. We show inactivation and reduced expression of FOXA1 and PTEN is prevalent in human disease, where PTEN and FOXA1 are downregulated by allelic loss and site-specific DNA hypermethylation, respectively. Conditional inactivation of both Foxa1 and Pten in intermediate/luminal cells in mice results in development of bladder cancer exhibiting squamous features as well as enhanced sensitivity to a bladder-specific carcinogen. In addition, FOXA1 is hypermethylated in basal bladder cancer cell lines, and this is reversed by treatment with DNA methyltransferase inhibitors. By integrating human correlative and in vivo studies, we define a critical role for PTEN loss and epigenetic silencing of FOXA1 in heterogeneous human disease and show genetic targeting of luminal/intermediate cells in mice drives squamous differentiation.

8.
Faraday Discuss ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31608916

RESUMO

A combined experimental and theoretical study is presented of several ligand addition reactions of the triplet fragment 3CpMn(CO)2 formed upon photolysis of CpMn(CO)3. Experimental data are provided for reactions in n-heptane and perfluoromethylcyclohexane (PFMCH), as well as in PFMCH doped with C2H6, Xe and CO2. In PFMCH we find that the conversion of 3CpMn(CO)2 to 1CpMn(CO)2(PFMCH) is much slower (τ = 18 (±3) ns) than the corresponding reactions in conventional alkanes (τ = 111 (±10) ps). We measure the effect of the coordination ability by doping PFMCH with alkane, Xe and CO2; these doped ligands form the corresponding singlet adducts with significantly variable formation rates. The reactivity as measured by the addition timescale follows the order 1CpMn(CO)2(C5H10) (τ = 270 (±10) ps) > 1CpMn(CO)2Xe (τ = 3.9 (±0.4) ns) ∼ 1CpMn(CO)2(CO2) (τ = 4.7 (±0.5) ns) > 1CpMn(CO)2(C7F14) (τ = 18 (±3) ns). Electronic structure theory calculations of the singlet and triplet potential energy surfaces and of their intersections, together with non-adiabatic statistical rate theory, reproduce the observed rates semi-quantitatively. It is shown that triplet adducts of the ligand and 3CpMn(CO)2 play a role in the kinetics, and account for the variable timescales observed experimentally.

9.
Sensors (Basel) ; 19(20)2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31635124

RESUMO

Presented is a flexible capacitive strain sensor, based on the low cost materials silicone (PDMS) and carbon black (CB), that was fabricated by casting and curing of successive silicone layers-a central PDMS dielectric layer bounded by PDMS/CB blend electrodes and packaged by exterior PDMS films. It was effectively characterized for large flexion-angle motion wearable applications, with strain sensing properties assessed over large strains (50%) and variations in temperature and humidity. Additionally, suitability for monitoring large tissue deformation was established by integration with an in vitro digestive model. The capacitive gauge factor was approximately constant at 0.86 over these conditions for the linear strain range (3 to 47%). Durability was established from consistent relative capacitance changes over 10,000 strain cycles, with varying strain frequency and elongation up to 50%. Wearability and high flexion angle human motion detection were demonstrated by integration with an elbow band, with clear detection of motion ranges up 90°. The device's simple structure and fabrication method, low-cost materials and robust performance, offer promise for expanding the availability of wearable sensor systems.

10.
BMC Plant Biol ; 19(1): 423, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31610785

RESUMO

BACKGROUND: Pink-flowered strawberry is a promising new ornamental flower derived from intergeneric hybridization (Fragaria × Potentilla) with bright color, a prolonged flowering period and edible fruits. Its flower color ranges from light pink to red. Pigment compounds accumulated in its fruits were the same as in cultivated strawberry fruits, but different from that in its flowers. However, the transcriptional events underlying the anthocyanin biosynthetic pathway have not been fully characterized in petal coloration. To gain insights into the regulatory networks related to anthocyanin biosynthesis and identify the key genes, we performed an integrated analysis of the transcriptome and metabolome in petals of pink-flowered strawberry. RESULTS: The main pigments of red and dark pink petals were anthocyanins, among which cyanidins were the main compound. There were no anthocyanins detected in the white-flowered hybrids. A total of 50,285 non-redundant unigenes were obtained from the transcriptome databases involved in red petals of pink-flowered strawberry cultivar Sijihong at three development stages. Amongst the unigenes found to show significant differential expression, 57 were associated with anthocyanin or other flavonoid biosynthesis, in which they were regulated by 241 differentially expressed members of transcription factor families, such as 40 MYBs, 47 bHLHs, and 41 NACs. Based on a comprehensive analysis relating pigment compounds to gene expression profiles, the mechanism of flower coloration was examined in pink-flowered strawberry. A new hypothesis was proposed to explain the lack of color phenotype of the white-flowered strawberry hybrids based on the transcriptome analysis. The expression patterns of FpDFR and FpANS genes corresponded to the accumulation patterns of cyanidin contents in pink-flowered strawberry hybrids with different shades of pink. Moreover, FpANS, FpBZ1 and FpUGT75C1 genes were the major factors that led to the absence of anthocyanins in the white petals of pink-flowered strawberry hybrids. Meanwhile, the competitive effect of FpFLS and FpDFR genes might further inhibit anthocyanin synthesis. CONCLUSIONS: The data presented herein are important for understanding the molecular mechanisms underlying the petal pigmentation and will be powerful for integrating novel potential target genes to breed valuable pink-flowered strawberry cultivars.

11.
ACS Sens ; 4(11): 3051-3055, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31591885

RESUMO

This paper reports a facile functionalization method on a metal-oxide semiconductor and a cuprous oxide (Cu2O) based chemiresistive electronic nose for the detection of volatile organic compounds (VOCs). A library of functionalized Cu2O nanospheres was developed through silanization using chemically diverse organosilanes. An electronic nose was fabricated with unmodified Cu2O nanospheres and five types of functionalized Cu2O nanospheres as the sensing elements. The electronic nose showed stable and rapid resistance responses to 25-200 ppm model VOCs, with the operating temperature of 180 °C. Single VOCs and ternary VOC mixtures could be discriminated by the electronic nose, and six types of tea leaves were also proved to be distinguishable as an illustration of the application of the electronic nose. We expected that the silanization could provide a simple approach for material diversification and the electronic nose would have further application in identification and discrimination of complex gas samples.

12.
J Adv Nurs ; 75(12): 3434-3447, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31566769

RESUMO

AIMS: To integrate the overall effect of e-health based self-management on cancer-related fatigue (CRF), self-efficacy, and quality of life (QOL) among adult cancer patients. DESIGN: A systematic review and meta-analysis of randomized controlled trials. DATA SOURCES: We researched PubMed, Cumulative Index Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, Web of Science and Embase up to 14 July 2019. REVIEW METHODS: We conducted the review with the Cochrane Handbook (version 5.1.0) and measured the quality of evidence with the Grading of Recommendations Assessment, Development and Evaluation criteria. RESULTS: Literature searching identified 15 trials with a total of 2,337 participants. Integrated results analysis of e-health based self-management demonstrated a statistically significant but small effect on CRF and self-efficacy, but no statistically significant improvement on the QOL. Meanwhile, subgroup analysis indicated that e-health based self-management had a larger effect on fatigue compared with usual care/waiting list control. CONCLUSION: E-health based self-management is effective for CRF and self-efficacy, but not the QOL. More high-quality randomized control trials are warranted to confirm these conclusions. IMPACT: Results showed e-health could improve fatigue and self-efficacy but not the QOL. Health providers could take into the various factors of e-health interventions when providing telehealth service. Other researchers might be inspired by the current review before they begin a study about e-health.

13.
Mol Biol Cell ; 30(24): 2969-2984, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31577526

RESUMO

The apical surface of the terminally differentiated mammalian urothelial umbrella cell is mechanically stable and highly impermeable, in part due to its coverage by urothelial plaques consisting of 2D crystals of uroplakin particles. The mechanism for regulating the uroplakin/plaque level is unclear. We found that genetic ablation of the highly tissue-specific sorting nexin Snx31, which localizes to plaques lining the multivesicular bodies (MVBs) in urothelial umbrella cells, abolishes MVBs suggesting that Snx31 plays a role in stabilizing the MVB-associated plaques by allowing them to achieve a greater curvature. Strikingly, Snx31 ablation also induces a massive accumulation of uroplakin-containing mitochondria-derived lipid droplets (LDs), which mediate uroplakin degradation via autophagy/lipophagy, leading to the loss of apical and fusiform vesicle plaques. These results suggest that MVBs play an active role in suppressing the excessive/wasteful endocytic degradation of uroplakins. Failure of this suppression mechanism triggers the formation of mitochondrial LDs so that excessive uroplakin membranes can be sequestered and degraded. Because mitochondrial LD formation, which occurs at a low level in normal urothelium, can also be induced by disturbance in uroplakin polymerization due to individual uroplakin knockout and by arsenite, a bladder carcinogen, this pathway may represent an inducible, versatile urothelial detoxification mechanism.

14.
Neurosci Lett ; 713: 134535, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31586698

RESUMO

The Schizophrenia Psychiatric GWAS Consortium (PGC) has identified the rs1625579 polymorphism in the MIR137 gene, which encodes miR-137, as the strongest new association with schizophrenia in the European population. However, whether the influence of rs1625579 on schizophrenia in the Asian population is consistent with these results remains unclear. A total of 21 studies (9878 schizophrenic patients and 9447 control subjects) that met the inclusion criteria were included in our meta-analysis. Pooled analysis, subgroup analysis, sensitivity analysis and publication bias were performed. The T allele, TT genotype and TT + GG genotype were associated with schizophrenia as risk factors. Subgroup analysis shows that no heterogeneity existed in the European and Asian populations. Our meta-analysis found that the Rs1625579 polymorphism in the MIR137 gene was associated with the risk of schizophrenia. The current findings provide a reference for case-control studies of schizophrenia in the future.

15.
Cancer Med ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31663692

RESUMO

Previous studies have shown that single-nucleotide polymorphisms (SNPs) of a disintegrin and metalloproteinase with thrombospondin type 1 motif 4 (ADAMTS4) may involve in the pathogenesis of some diseases. However, it is not clear whether they are associated with hepatocellular carcinoma (HCC). A hospital-based case-control study, including 862 cases with HCC and 1120 controls, was conducted to assess the effects of 258 SNPs in the coding regions of ADAMTS4 on HCC risk and prognosis. We found that six SNPs in ADAMTS4 were differential distribution between cases and controls via the primary screening analyses; however, only rs538321148 and rs1014509103 polymorphisms were further identified to modify the risk of HCC (odds ratio: 2.73 and 2.95; 95% confidence interval, 2.28-3.29 and 2.43-3.58; P-value, 5.73 × 10-27 and 1.36 × 10-27 , respectively). Significant interaction between these two SNPs and two known causes of hepatitis B virus and aflatoxin B1 were also observed. Furthermore, rs538321148 and rs1014509103 polymorphisms were associated not only with clinicopathological features of tumor such as tumor stage and grade, microvessel density, and vessel metastasis, but with poor overall survival. Additionally, these SNPs significantly downregulated ADATMS4 expression in tumor tissues. These data suggest that SNPs in the coding region of ADAMTS4, such as rs538321148 and rs1014509103, may be potential biomarkers for predicting HCC risk and prognosis.

16.
Sci Transl Med ; 11(512)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578243

RESUMO

High serum concentrations of kidney-derived protein uromodulin [Tamm-Horsfall protein (THP)] have recently been shown to be independently associated with low mortality in both older adults and cardiac patients, but the underlying mechanism remains unclear. Here, we show that THP inhibits the generation of reactive oxygen species (ROS) both in the kidney and systemically. Consistent with this experimental data, the concentration of circulating THP in patients with surgery-induced acute kidney injury (AKI) correlated with systemic oxidative damage. THP in the serum dropped after AKI and was associated with an increase in systemic ROS. The increase in oxidant injury correlated with postsurgical mortality and need for dialysis. Mechanistically, THP inhibited the activation of the transient receptor potential cation channel, subfamily M, member 2 (TRPM2) channel. Furthermore, inhibition of TRPM2 in vivo in a mouse model mitigated the systemic increase in ROS during AKI and THP deficiency. Our results suggest that THP is a key regulator of systemic oxidative stress by suppressing TRPM2 activity, and our findings might help explain how circulating THP deficiency is linked with poor outcomes and increased mortality.

17.
J Investig Med ; 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31630138

RESUMO

Estimated glomerular filtration rate (eGFR) is an important topic in patients with primary aldosteronism (PA). However, the relationship between left ventricular structure and eGFR is unclear. We conducted a prospective, observational, and cross-sectional study to analyze 168 patients with PA and 168 propensity score-matched patients with essential hypertension (EH) as the control group, matched by age, gender, and systolic blood pressure. In the patients with PA, the eGFR was not correlated with left ventricular mass index (LVMI; r=-0.065, p=0.404), while in the patients with EH, the eGFR was negatively correlated with LVMI (r=-0.309, p<0.001). To test whether eGFR had a non-linear relationship with LVMI among the patients with PA, we stratified the patients with PA according to the tertile of eGFR (low, medium, and high tertile). The medium tertile of patients had a significantly lower LVMI than those in the other two tertiles (LVMI: 143.5±41.6, 120.5±40.5, and 133.1±34.3 g/m2, from the lowest to highest tertile of eGFR; analysis of covariance p=0.032). The medium tertile of eGFR is associated with lowest LVMI. Patients with PA with high and low eGFR were associated with higher LVMI. The findings implied that the reasons for an increased LVMI in patients with PA may be different to those in patients with EH.

18.
Genes (Basel) ; 10(10)2019 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614865

RESUMO

This study identified a transcription factor that might bind to the 5' regulatory region of the HTR1A and explored the potential effect on 5-HT1A receptor expression. Based on JASPAR predictions, the binding of the transcription factor was demonstrated using the electrophoretic mobility shift assay (EMSA). Vectors over-expressing the transcription factor were co-transfected into HEK-293 and SK-N-SH cells with the recombinant pGL3 vector, and relative fluorescence intensity was measured to determine regulatory activity. Additionally, the qRT-PCR and Western blot were also used to identify whether the transcription factor modulated the endogenous expression of 5-HT1A receptor. The results suggest that the transcription factor CCAA/T enhancer binding protein beta (CEBPB) likely binds to the -1219 to -1209 bp (ATG+1) region of the HTR1A. Two sequences located in the -722 to -372 bp and -119 to +99 bp were also identified. Although the effect of CEBPB on endogenous 5-HT1A receptor expression was not significant, it exhibited the strong inhibition on the relative fluorescence intensity and the mRNA level of HTR1A. CEBPB inhibited the human HTR1A expression by binding to the sequence -1219 - -1209 bp. This is useful and informative for ascertaining the regulation of 5-HT1A receptor and mental diseases.

19.
Proc Natl Acad Sci U S A ; 116(43): 21727-21731, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31591243

RESUMO

Electronic-cigarettes (E-cigs) are marketed as a safe alternative to tobacco to deliver the stimulant nicotine, and their use is gaining in popularity, particularly among the younger population. We recently showed that mice exposed to short-term (12 wk) E-cig smoke (ECS) sustained extensive DNA damage in lungs, heart, and bladder mucosa and diminished DNA repair in lungs. Nicotine and its nitrosation product, nicotine-derived nitrosamine ketone, cause the same deleterious effects in human lung epithelial and bladder urothelial cells. These findings raise the possibility that ECS is a lung and bladder carcinogen in addition to nicotine. Given the fact that E-cig use has become popular in the past decade, epidemiological data on the relationship between ECS and human cancer may not be known for a decade to come. In this study, the carcinogenicity of ECS was tested in mice. We found that mice exposed to ECS for 54 wk developed lung adenocarcinomas (9 of 40 mice, 22.5%) and bladder urothelial hyperplasia (23 of 40 mice, 57.5%). These lesions were extremely rare in mice exposed to vehicle control or filtered air. Current observations that ECS induces lung adenocarcinomas and bladder urothelial hyperplasia, combined with our previous findings that ECS induces DNA damage in the lungs and bladder and inhibits DNA repair in lung tissues, implicate ECS as a lung and potential bladder carcinogen in mice. While it is well established that tobacco smoke poses a huge threat to human health, whether ECS poses any threat to humans is not yet known and warrants careful investigation.

20.
Nanoscale ; 11(38): 17860-17868, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31553002

RESUMO

In this work, the impact of oxygen vacancies and nitrogen-doped carbon coating on the sodium-ion storage properties of anatase TiO2 has been demonstrated. Oxygen vacancies and nitrogen-doped carbon coating were introduced simultaneously by the calcination of core-shell structured TiO2 spheres in a reducing atmosphere. Compared to the anatase TiO2 with and without oxygen vacancies, TiO2-x@NC exhibits much better electrochemical performance in the storage of sodium ions. A high reversible capacity of 245.6 mA h g-1 is maintained at 0.1 A g-1 after 200 cycles, and a high specific capacity of 155.6 mA h g-1 is achieved at a high rate of 5.0 A g-1. The significantly improved electrochemical performance of the core-shell structured anatase TiO2 spheres is attributed to the synergistic effect of the oxygen vacancies in the anatase lattice and surface nitrogen-doped carbon coating. This work provides an efficient strategy for improving the electrochemical performance of metal-oxide-based electrode materials for sodium-ion batteries.

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