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1.
J Med Internet Res ; 21(9): e14484, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31482855

RESUMO

BACKGROUND: Web-based health communities provide means for patients to not only seek care but also to promote their relationship with doctors. However, little is known about the predictors of patients' loyalty toward doctors in Web-based health communities. OBJECTIVE: This study aimed to investigate the predictors of patients' loyalty toward doctors in Web-based health communities. METHODS: On the basis of sociotechnical systems theory and attachment theory, we propose that social factors including emotional interaction, perceived expertise, and social norm influence patients' loyalty through their emotional attachment, whereas technical factors including sociability, personalization, and perceived security affect patients' loyalty through functional dependence. To validate our proposed research model, we used the survey method and collected 373 valid answers. Partial least square was used to analyze the data. RESULTS: Our empirical analysis results showed that all the social factors including emotional interaction (beta=.257, t350=2.571; P=.01), perceived expertise (beta=.288, t350=3.412; P=.001), and social norm (beta=.210, t350=2.017; P=.04) affect patients' emotional attachment toward doctors significantly, whereas except sociability (beta=.110, t350=1.152; P=.25), technical factors such as personalization (beta=.242, t350=2.228; P=.03) and perceived security (beta=.328, t350=3.438; P=.001) impact functional dependence significantly. Considering the effect of working mechanisms, both emotional attachment (beta=.443, t350=4.518; P<.001) and functional dependence (beta=.303, t350=2.672; P=.008) influence patients' loyalty toward doctors in Web-based health communities significantly. CONCLUSIONS: Patients' loyalty toward doctors in Web-based health communities is important for the effectiveness of doctors' advice or service in Web-based health communities. The research results not only fill the gaps in the literature of the patient-doctor relationship and Web-based health communities but also has many implications for establishing patients' loyalty on Web-based health communities and in physical context.

2.
BMC Health Serv Res ; 19(1): 654, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31500617

RESUMO

BACKGROUND: Integration of medical insurance schemes has been prioritized as one of the key strategies to address inequity in China's health system. The first pilot attempt to integrate started in 2003 and later expanded nationwide. This study aims to assess its intended impact on inequity in inpatient service utilization and identify the main determinants contributing to its ineffectiveness. METHODS: A total of 49,365 respondents in the pilot integrated area and 77,165 respondents in the non-integration area were extracted from the Fifth National Health Services Survey. A comparative analysis was conducted between two types of areas. We calculate a concentration index (CI) and horizontal inequity index (HI) in inpatient service utilization and decompose the two indices. RESULTS: Insurance integration played a positive role in reducing inequality in inpatient service utilization to some extent. A 13.23% lower in HI, a decrease in unmet inpatient care and financial barriers to inpatient care in the pilot integrated area compared with the non-integration area; decomposition analysis showed that the Urban-Rural Residents Basic Medical Insurance, a type of integrated insurance, contributed 37.49% to reducing inequality in inpatient service utilization. However, it still could not offset the strong negative effect of income and other insurance schemes that have increased inequality. CONCLUSIONS: The earlier pilot attempt for integrating medical insurance was not enough to counteract the influence of factors which increased the inequality in inpatient service utilization. Further efforts to address the inequality should focus on widening access to financing, upgrading the risk pool, reducing gaps within and between insurance schemes, and providing broader chronic disease benefit packages. Social policies that target the needs of the poor with coordinated efforts from various levels and agencies of the government are urgently needed.

3.
Ecotoxicol Environ Saf ; 183: 109590, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31509933

RESUMO

Cadmium (Cd) is associated with barite; however, its biogeochemical characteristics in environments impacted by barium (Ba) mining are not known. Here, we first revealed the characteristics of Cd concentrations, distributions, and chemical forms in the soil-rice system in Ba mining areas. The associated exposure and risk assessments of Cd via rice consumption were also conducted. Elevated levels of Cd with a wide range of 0.054-91 mg/kg were found in paddy soils, approximately 63% of which exceeded the national Grade II value for soil Cd levels in China (0.3 mg/kg). A significant positive correlation between the soil Cd and soil Ba demonstrated that large amounts of Cd were released into the environment from Ba mining. Cadmium accumulated remarkably in the rice grains (0.007-3.5 mg/kg). The chemical forms in the rice plants indicated that most of the Cd was in the pectate/protein fraction (F2, 92% in the grains and 61-71% in the other tissues), followed by the residual fraction (F3, 7.1% in the grains, 27-38% in the other tissues). A minor portion of Cd was in the soluble and aminophenol fraction (F1, 0.44% in the grains, 0.26-1.4% in the other tissues). The positive correlations observed between the grain Cd and F2 in the roots, stems and leaves suggested that Cd in the rice grain was mainly from F2. Similarly, the root F2 was also positively correlated with that in the stems/leaves, indicating the critical role of F2 in Cd2+ migration in rice tissues. The estimated average hazard quotient (2.5) and annual excess lifetime cancer risk (21 × 10-5 a-1) were higher than the safety levels of 1 and 5.0 × 10-5 a-1, respectively, showing that the dietary intake of Cd via rice consumption posed high health risks to residents. Our study demonstrated that more concerns should be paid to Cd contamination in Ba mining areas.

4.
Soc Sci Med ; 238: 112518, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31473574

RESUMO

The potential benefit of social participation (SP) to one's mental health has been widely acknowledged. Nevertheless, the specific type and amount of SP that is associated with improved depressive symptoms in middle- and old-aged Chinese awaits further investigation. This study aimed to understand the patterns of depression and SP by comparing urban vs rural China, and according to which, measure the associations between changes in SP and that in depressive symptoms. A total of 10,988 community residents aged 45 years and above were selected from wave 1 (2011), wave 2 (2013), and wave 4 (2015) of the China Health and Retirement Longitudinal Study (CHARLS), a nationally representative survey. The fixed-effects analysis was used to explore the association between the changes in diversity, frequency, and type of SP and the changes in depressive symptoms. The results indicated that rural respondents suffered from a significantly higher risk of depression and took less SP than their urban counterparts. Transitioning from no SP to 1 or more types of SP or to a once a week or higher frequency was associated with a decline in depressive symptoms. For urban respondents, playing mah-jong or cards and joining sports or social clubs predicted a decline in depressive symptoms. For rural residents, interacting with friends regularly was associated with fewer depressive symptoms. In conclusion, more diverse and higher frequency of SP was associated with better mental health, while the social significance of SP varied across different types of SP and between rural and urban areas.

5.
J Clin Invest ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31449053

RESUMO

Microtubule-associated serine/threonine kinase 1 (MAST1) is a central driver of cisplatin resistance in human cancers. However, the molecular mechanism regulating MAST1 levels in cisplatin-resistant tumors is unknown. Through a proteomics screen, we identified the heat shock protein 90 B (hsp90B) chaperone as a direct MAST1 binding partner essential for its stabilization. Targeting hsp90B sensitized cancer cells to cisplatin predominantly through MAST1 destabilization. Mechanistically, interaction of hsp90B with MAST1 blocked ubiquitination of MAST1 at lysines 317 and 545 by the E3 ubiquitin ligase CHIP and prevented proteasomal degradation. The hsp90B-MAST1-CHIP signaling axis and its relationship with cisplatin response were clinically validated in cancer patients. Furthermore, combined treatment with a hsp90 inhibitor and the MAST1 inhibitor lestaurtinib further abrogated MAST1 activity and consequently enhanced cisplatin-induced tumor growth arrest in a patient-derived xenograft model. Our study not only uncovers the regulatory mechanism of MAST1 in tumors but also suggests a promising combinatorial therapy to overcome cisplatin resistance in human cancers.

6.
Autism Res ; 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31369217

RESUMO

Altered patterns of visual social attention preference detected using eye-tracking and a variety of different paradigms are increasingly proposed as sensitive biomarkers for autism spectrum disorder. However, few eye-tracking studies have compared the relative efficacy of different paradigms to discriminate between autistic compared with typically developing children and their sensitivity to specific symptoms. To target this issue, the current study used three common eye-tracking protocols contrasting social versus nonsocial stimuli in young (2-7 years old) Chinese autistic (n = 35) and typically developing (n = 34) children matched for age and gender. Protocols included dancing people versus dynamic geometrical images, biological motion (dynamic light point walking human or cat) versus nonbiological motion (scrambled controls), and child playing with toy versus toy alone. Although all three paradigms differentiated autistic and typically developing children, the dancing people versus dynamic geometry pattern paradigm was the most effective, with autistic children showing marked reductions in visual preference for dancing people and correspondingly increased one for geometric patterns. Furthermore, this altered visual preference in autistic children was correlated with the Autism Diagnostic Observation Schedule social affect score and had the highest discrimination accuracy. Our results therefore indicate that decreased visual preference for dynamic social stimuli may be the most effective visual attention-based paradigm for use as a biomarker for autism in Chinese children. Clinical trial ID: NCT03286621 (clinicaltrials.gov); Clinical trial name: Development of Eye-tracking Based Markers for Autism in Young Children. Autism Res 2019, 00: 1-12. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Eye-tracking measures may be useful in aiding diagnosis and treatment of autism, although it is unclear which specific tasks are optimal. Here we compare the ability of three different social eye-gaze tasks to discriminate between autistic and typically developing young Chinese children and their sensitivity to specific autistic symptoms. Our results show that a dynamic task comparing visual preference for social (individuals dancing) versus geometric patterns is the most effective both for diagnosing autism and sensitivity to its social affect symptoms.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31373432

RESUMO

Reported herein is a visible-light-driven intramolecular C-N cross-coupling reaction under mild reaction conditions (metal- and photocatalyst-free, at room temperature) via a long-lived photoactive photoisomer complex. This strategy was used to rapidly prepare the N-substituted polycyclic quinazolinone derivatives with a broad substrate scope (>50 examples) and further exploited to synthesize the natural products tryptanthrin, rutaecarpine, and their analogues. The success of gram-scale synthesis and solar-driven transformation, as well as promising tumor-suppressing biological activity, proves the potential of this strategy for practical applications. Mechanistic investigations, including control experiments, DFT calculations, UV-vis spectroscopy, EPR, and X-ray single-crystal structure of the key intermediate, provides insight into the mechanism.

9.
Sci Rep ; 9(1): 11853, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31413306

RESUMO

Pathway analysis allows us to gain insights into a comprehensive understanding of the molecular mechanisms underlying cancers. Currently, high-throughput multi-omics data and various types of large-scale biological networks enable us to identify cancer-related pathways by comprehensively analyzing these data. Combining information from multidimensional data, pathway databases and interaction networks is a promising strategy to identify cancer-related pathways. Here we present a novel network-based approach for integrative analysis of DNA methylation and gene expression data to extend original pathways. The results show that the extension of original pathways can provide a basis for discovering new components of the original pathway and understanding the crosstalk between pathways in a large-scale biological network. By inputting the gene lists of the extended pathways into the classical gene set analysis (ORA and FCS), we effectively identified the altered pathways which are correlated well with the corresponding cancer. The method is evaluated on three datasets retrieved from TCGA (BRCA, LUAD and COAD). The results show that the integration of DNA methylation and gene expression data through a network of known gene interactions is effective in identifying altered pathways.

10.
PLoS One ; 14(8): e0221430, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31425559

RESUMO

BACKGROUND: The general benefit of physical activity (PA) to one's mental health has been widely acknowledged. Nevertheless, the specific type and amount of PA that associates with lower risk of depression in China awaits further investigation. The present study was conducted on middle- and older-aged Chinese population with two objectives: 1) to understand the patterns of PA; 2) to measure the associations between depression and PA at different levels from various aspects. METHODS: Using data from the China Health and Retirement Longitudinal Study (CHARLS, 2015), we selected 9118 community residents aged 45 years and older. Depressive symptoms were measured by 10-item Center for Epidemiologic Studies (CES-D 10). Multivariate logistic regression model was performed to examine the association between risk of depression and PA from four aspects including intensity, frequency, duration, and volume. RESULTS: Spending 1-2 days/week (OR = 0.58, 95% CI: 0.36, 0.91), less than 30 minutes each time (OR = 0.66, 95% CI: 0.42, 1.03) or 150-299 min/week (OR = 0.49, 95% CI: 0.28, 0.87) on Moderate Physical Activity (MPA) was associated with lower odds of depression in women. Spending 3-5 days/week (OR = 1.98, 95% CI: 1.29, 3.05) or 6-7 days/week (OR = 1.50, 95% CI: 1.07, 2.11), 4 hours and longer each time (OR = 1.65, 95% CI: 1.18, 2.32), 300 min/week or longer (OR = 1.65, 95% CI: 1.22, 2.24) on Vigorous Physical Activity (VPA) in total, or 2250 Metabolic Equivalent of Task (OR = 1.73, 95% CI: 1.26, 2.38) on Moderate-to-Vigorous PA was associated with higher risk of depression in men. CONCLUSIONS: The association between depression and PA depended largely on intensity and gender. Lower frequency, shorter duration, and moderate amount of MPA was associated with lower risk of depression in women. Risk of depression was higher in men who spent higher frequency, longer duration, and overlong time on VPA.

11.
Eur J Oncol Nurs ; 42: 7-13, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31446267

RESUMO

PURPOSE: The chemotherapy-induced taste alteration scale (CiTAS) is a reliable and valid instrument to comprehensively assess patients' taste alterations in an easy way. We aimed to translate it and test its psychometric properties among Chinese cancer patients undergoing chemotherapy. METHOD: A convenience sample of 227 cancer patients were recruited in a tertiary cancer hospital in Beijing. The Chinese version of the CiTAS (C-CiTAS) was developed via rigorous translation methods. An exploratory structural equation model (ESEM) was used to test its construct validity. Correlations between the C-CiTAS scores and the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 scores were calculated for convergent validity. The overall taste alterations scale (OTAS) score was used to test its discriminant validity. Reliabilities were also examined. RESULTS: The majority of patients undergoing chemotherapy experienced minor to mild taste alterations. The current factor analysis results using the ESEM supported the original factor solution of the CiTAS, and no item of the CiTAS was dropped. The C-CiTAS demonstrated good construct validity, convergent validity and discriminant validity. The Cronbach's alphas of the C-CiTAS were 0.900 for the overall scale and from 0.570 to 0.857 for the four subscales. Its test-retest reliability was 0.815 (p < 0.01). CONCLUSIONS: The Chinese version of the CiTAS is a reliable and valid instrument to evaluate cancer patients' Chemotherapy-induced taste alterations in China.

12.
Nanotechnology ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31469113

RESUMO

Heteroatom doped carbon nanomaterials are often employed as advanced anode for Lithium ions battery (LIBs) in terms of their stable structure, high capacity and low cost. In this work, we proposed a novel strategy to synthesize high density (N, Ni, P) tri-doped echinus-like porous carbon spheres (PCS) by carbonizing a metal-organophosphine framework (MOPF) directly. The MOPF employs riboflavin sodium phosphate (C17H20N4NaO9P) as organic ligand as well as nitrogen and phosphorus source to conjugate with Ni(NO3)2·6H2O. As anode for LIBs, PCS was demonstrated that the discharge capacities were able to reach 386.5 mAh·g-1 after 100 cycles at current density of 0.05 A·g-1. Besides, the stable reversible capacities were obtained from ~459 mAh·g-1 to ~91.8 mAh·g-1 when current density varied from 0.05 to 1 A·g-1. The good anode performance is attributed to the unique structure of PCS and (N, Ni, P) tri-doping which introduces the additional capacities due to the presence of "reservoir effect". Moreover, the electrochemical analysis implied that the surface-limited capacitive behavior dominantly contributes to the lithium storage capacity of PCS anode.

13.
Zhen Ci Yan Jiu ; 44(7): 469-75, 2019 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-31368275

RESUMO

OBJECTIVE: To observe the effect of acupuncture and moxibustion on renal Fas and Fas ligand (FasL) expression in contrast-induced nephropathy (CIN) diabetic rats, so as to explore its protective mechanisms. METHODS: A total of 40 diabetic male SD rats were randomly divided into control, model, acupuncture, moxibustion and combined treatment (acupuncture combined with moxibustion) groups (n=8 rats in each group). The diabetic model was established by i.p. injection of Streptozotocin (60 mg/kg), followed by regular raising for 9 weeks. Then, the manual acupuncture, moxibustion or acupuncture plus moxibustion at "Sanyinjiao"(SP6) "Shenshu"(BL23) and "Pishu"(BL20) was given to the diabetic rats, once daily for 7 days. On the 8th day, these diabetic rats received i.p. injection of compound Meglumine Diatrizoate Injection (10 mL/kg) for establishing CIN model. Then, the venous blood specimens were collected for detecting contents of serum urine nitrogen (BUN, with urease method) and creatinine (Scr, with picric acid method). The kindey tissues were exteriorized for detecting nitricoxide synthase (NOS, with oxidation-reduction method), malondialdehyde (MDA, with thiobarbituric acid method), superoxide dismutase (SOD, with xanthine oxidase technique) and total antioxidant capacity (T-AOC, with colorimetric technique). The expression levels of Fas and FasL in the kidney tissues were detected by quantitative real-time PCR and Western blot separately. The histopathological and ultrastructural changes of the kidney were observed under microscope (after H.E. staining) and transmission electron microscope, respectively. RESULTS: Following modeling and compared with the control group, the BUN, Scr and renal MDA contents, and Fas and FasL mRNA and protein expression levels were significantly increased (P<0.01, P<0.05), and renal NOS, SOD and T-AOC levels considerably decreased in the model group (P<0.05). After the interventions and compared with the model group, serum BUN and Scr contents and renal Fas mRNA and protein expression levels in both acupuncture group and combined treatment group, BUN in the moxibustion group, and renal MDA content and FasL mRNA and protein expression levels in the 3 treatment groups were obviously down-regulated (P<0.05,P<0.01), while renal NOS in the 3 treatment groups, and SOD and T-AOC levels in the combined treatment group were considerably up-regulated (P<0.01,P<0.05). The effects of the combined treatment were significantly superior to those of simple acupuncure and simple moxibustion in down-regulating serum BUN contents, and Fas and FasL mRNA and protein expression levels, and in up-regulating renal NOS, SOD and T-AOC activity (P<0.05). No significant differences were found between the acupuncture and moxibustion groups in down-regulating serum BUN, Scr and renal MDA contents, and Fas and FasL mRNA and protein levels, as well as in up-regulating NOS content (P>0.05). H.E. staining showed lobular changes of glomeruli, many local necrosis and vascular degeneration in the model group, and transmission electron microscope displayed thickened basement membrane of the glomerular blood loop, many vacuoles in the cytoplasm of renal tubular epithelial cells, severely swollen mitochondria with disordered, broken or disappeared cristae, and some apoptotic cells in the model group, which were relatively milder in the combined treatment group. CONCLUSION: Joint application of acupuncture and moxibustion can reduce the oxidative stress and renal injury in CIN diabetic rats, which may be associated with its function in down-regulating the expression of renal Fas and FasL genes and proteins. Acupuncture and moxibustion has a synergistic effect.


Assuntos
Terapia por Acupuntura , Diabetes Mellitus Experimental , Moxibustão , Animais , Proteína Ligante Fas , Rim , Masculino , RNA Mensageiro , Ratos , Ratos Sprague-Dawley
14.
PLoS Biol ; 17(8): e3000086, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31433818

RESUMO

Lengthy use of general anesthetics (GAs) causes neurobehavioral deficits in the developing brain, which has raised significant clinical concerns such that the United States Food and Drug Administration (FDA) is warning on the use of GAs in children younger than 3 years. However, the molecular and cellular mechanisms for GAs-induced neurotoxicity remain largely unknown. Here, we report that sevoflurane (Sevo), a commonly used GA in pediatrics, caused compromised astrocyte morphogenesis spatiotemporally correlated to synaptic overgrowth, with reduced synaptic function in developing cortex in a regional-, exposure-length-, and age-specific manner. Sevo disrupted astrocyte Ca2+ homeostasis both acutely and chronically, which led to the down-regulation of Ezrin, an actin-binding membrane-bound protein, which we found was critically involved in astrocyte morphogenesis in vivo. Importantly, overexpression of astrocyte Ezrin rescued astrocytic and neuronal dysfunctions and fully corrected deficits in social behaviors in developing mice with lengthy Sevo exposure. Our data uncover that, in addition to neurons, astrocytes may represent important targets for GAs to exert toxic effects and that astrocyte morphological integrity is crucial for synaptogenesis and neurological behaviors.

15.
Arch Pharm (Weinheim) ; 352(8): e1900066, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31373047

RESUMO

A series of pyrazolo[3,4-b]pyridine derivatives were designed, synthesized, and evaluated for their activation activity toward adenosine 5'-monophosphate-activated protein kinase (AMPK). According to the enzyme activity, the pyrazole N-H exposure and para substitution on the diphenyl group were proved to be essential for the activation potency. Compound 17f showed equal activation compared with A-769662. In the molecular modeling study, compound 17f exhibited important hydrogen bond interaction with Lys29, Asp88, and Arg83. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays on the NRK-49F cell line showed that potent enzyme activators could effectively inhibit cell proliferation, especially for 17f (EC50 [AMPKα1γ1ß1] = 0.42 µM, efficacy = 79%; IC50 [NRK-49F cell line] = 0.78 µM). These results might provide new insights to explore novel AMPK activators.

16.
Mini Rev Med Chem ; 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362687

RESUMO

Soluble guanylate cyclase (sGC) is the intracellular receptor of messenger nitric oxide (NO). The activation of sGC results in the conversion of guanosine triphosphate (GTP) to the secondary messenger cyclic guanosine monophosphate (cGMP). cGMP modulates a series of cascades downstream through activating a variety of effectors, such as phosphodiesterase (PDE), protein kinase G (PKG), cyclic nucleotide gated ion channels (CNG). The NO-sGC-cGMP pathway play significant roles in various physiological processes, including platelet aggregation, smooth muscle relaxation and neurotransmitter delivery. Riociguat, as a sGC stimulator, has been approved for the treatment of pulmonary arterial hypertension (PAH), but enthusiasm on discovery of sGC modulators continues for their potential new applications. Notably, through activating the pathway, sGC stimulators and activators are potential therapies for the treatment of diverse diseases, such as PAH, heart failure (HF), diabetic nephropathy (DN) and systemic sclerosis (SS) as well as other diseases including sickle cell disease (SCD) and central nervous system (CNS) disease. Here, we review the preclinical and clinical studies of sGC stimulators and activators covering different diseases in recent five years and prospect the development of sGC modulators in the near future.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31441639

RESUMO

Due to the inherent toxicity of cadmium selenide (CdSe)-based quantum dots (QDs), Cd-free alternatives are being widely investigated. Indium phosphide (InP) QDs have shown great potential as a replacement for CdSe QDs in display applications. However, the performance of InP-based quantum dot light-emitting diodes (QLEDs) is still far behind that of the CdSe-based devices. In this study, we wanted to show the effects of different approaches to improving the performance of InP-based QLED devices. We investigated the effect of magnesium (Mg) doping in ZnO nanoparticles, which is used as an n-type electron transport layer, in balancing the charge transfer in InP-based QLED devices. We found that an increasing Mg doping level can broaden ZnO band gap, shift its energy levels, but most importantly, increase its resistivity; as a result, the electron current density is significantly reduced and the device efficiency is improved. We also investigated the effect of high-photoluminescence quantum yield emitters and different QLED architectures on the device performance. Through optimizing QD structures and devices, red InP QLEDs with the current efficiencies as high as 11.6 cd/A were fabricated.

18.
Bioanalysis ; 11(13): 1275-1289, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31298556

RESUMO

Aim: Recent advances in microflow ultra performance liquid chromatography (UPLC) systems offer higher sensitivity with robustness to meet the routine bioanalytical demands. Modern high-resolution mass spectrometers (HRMS) enable the development of highly selective methods with broad dynamic range. Results: The quantitative performances of tandem quadrupole MS and HRMS were comprehensively compared using seven intact peptide hormones up to 9.4 kDa. Results show comparable performance between two platforms in sensitivity, accuracy and linearity. For some peptides, HRMS provided lower background interference. The benefit of increased sensitivity using microflow UPLC was also demonstrated. Conclusion: HRMS is a versatile platform capable of both basic characterization and reliable quantitation in complex matrices. Microflow UPLC provides lower LLOQs than conventional flow systems, even with less sample volume injected.

19.
ACS Appl Mater Interfaces ; 11(33): 29807-29813, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361119

RESUMO

Alkali metal-sulfur/selenium batteries have attracted much attention because they offer promising high energy density. However, the shuttle effect of the polysulfide dissolutions, poor electrical conductivity, and relatively large volume variations greatly hinder their potential applications. Herein, a novel organic carbon/selenium sulfide (OC/SeS2) composite has been prepared by a one-step in situ method by heating the mixture of commercial polyacrylonitrile (PAN) with selenium sulfide powder in vacuum. The carbonized PAN matrix with an N-doped carbon ring structure could effectively confine SeS2 in the form of small molecules and regulate its electronic structure. The superior sodium/potassium storage performance of the OC/SeS2 composite electrodes stems from their rational chemical structure design, including high electrical conductivity of the N-doped organic carbon network and chemical binding with SeS2 molecules. As a result, the OC/SeS2 cathode delivers a reversible capacity of 416 mAh g-1 after 700 cycles for sodium-ion batteries and 216 mAh g-1 after 500 cycles for potassium-ion batteries at 0.5 A g-1, respectively. These findings could open a new window to develop selenium sulfide cathode for metal-sulfur/selenium batteries.

20.
Angew Chem Int Ed Engl ; 58(35): 12195-12199, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31286625

RESUMO

The detection of circulating tumor cells (CTCs) is crucial to early cancer diagnosis and the evaluation of cancer metastasis. However, it remains challenging due to the scarcity of CTCs in the blood. Herein, we report an ultrasensitive platform for the direct detection of CTCs using luminescent lanthanide nanoprobes. These were designed to recognize the epithelial cell adhesion molecules on cancer cells, allowing signal amplification through dissolution-enhanced time-resolved photoluminescence (TRPL) and the elimination of short-lived autofluorescence interference. This enabled the direct detection of blood breast-cancer cells with a limit of detection down to 1 cell/well of a 96-well plate. Moreover, blood CTCs (≥10 cells mL-1 ) can be detected in cancer patients with a detection rate of 93.9 % (14/15 patients). We envision that this ultrasensitive detection platform with excellent practicality may provide an effective strategy for early cancer diagnosis and prognosis evaluation.

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