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1.
Inorg Chem ; 59(6): 3562-3569, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32083853

RESUMO

Phenoxyl radical was generally suggested as the intermediate during copper-catalyzed aerobic oxygenation of phenols. However, the substrate-dependent selectivity has not been well interpreted, due to insufficient characterization of the radical intermediate under reaction conditions. When studying the CuCl-LiCl-catalyzed aerobic phenol oxidation, we obtained EPR spectra of phenoxyl radicals generated by oxidizing phenols with the preactivated catalyst. Upon correlation to the selectivity of benzoquinone, the hyperfine coupling constant of para-site proton (aH, para) was found to be better than the Hammett constant. The catalysis mechanism was studied based on EPR detection and the reaction results of phenoxyl radicals under N2 or O2 atmosphere. It appeared that the chemoselectivity depended on the attack of activated dioxygen on phenoxyl radicals, and the activation of dioxygen by [CunCln+1]- (n = 1, 2, 3) was suggested as the rate-determining step. Understanding of the substrate-dependent selectivity contributed to predicting the chemoselectivity in the aerobic oxidation of phenols.

2.
Inorg Chem ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32105460

RESUMO

Full visible emission achieved by a single-phased system is of great interest to researchers for the development of high-quality solid-state lighting devices. Herein, novel Eu2+ and Mn2+ co-doped (1 - x)ß-Ca3(PO4)2-xCa9La(PO4)7 solid solution phosphors are designed to realize single-phased white light emission. The effects of variational x on lattice structure, color-tunable emission, thermal stability, and energy-transfer efficiency from Eu2+ to Mn2+ are systematically investigated. Tunable color emissions are achieved by manipulating the redistributions of Eu2+ ions among the different cationic sites under the influence of generated empty site in the M(4) site. Meanwhile, the changes of critical distances among the Eu2+ and Mn2+ caused by the variational x results in the changes of energy-transfer efficiency from different Eu2+ luminescent centers to Mn2+ due to the existence of structural confinement effect. The calculated results indicate that Eu1-Mn and Eu2-Mn possess higher energy-transfer efficiencies than other Eu-Mn pairs. Under the combined influence of the two effects, single-phased full visible white emission covering from 400 to 700 nm has been realized via the adjustment of solid solution, which makes the fabricated white-light-emitting diode (WLED) possess high color-rendering index (86.9) and R9 (87.2) as well as low correlated color temperature (3947 K). The results show that the 0.2ß-Ca3(PO4)2-0.8Ca9La(PO4)7:0.01Eu2+, 0.20Mn2+ could act as a promising phosphor for single-phased WLEDs. This work will open up a new avenue for tuning the multiple activator sites and energy-transfer efficiencies simultaneously to realize single-phased full visible white emission.

3.
Biol Reprod ; 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32072170

RESUMO

S100A4 has been suggested to be a critical regulator of tumor metastasis and is implicated in the progression of inflammation. The aim of this study is to investigate the expression and possible role of S100A4 in epididymitis. Using a mouse model of epididymitis induced by the injection of lipopolysaccharide (LPS) in the deferent duct, we found that LPS administration induced an upregulation of S100a4 transcription (P < 0.05) and a recruitment of S100A4 positive cells in the epididymal interstitium of wild type (WT) mice. Co-immunofluorescence showed that S100A4 was mainly expressed by granulocytes, CD4 lymphocytes and macrophages. Deficiency of S100A4 reduced epididymal pathological reaction and the mRNA levels of the pro-inflammatory cytokines IL-1ß and TNF-α (P < 0.01), suggesting that S100A4 promotes the progression of epididymitis. Furthermore, S100A4 deficiency alleviated the decline of sperm motility and rectified the abnormal expression of sperm membrane protein AMAD3, which suggested that in the progression of epididymitis, S100A4 aggravates the damage to sperm vitality. In addition, both Ki-67 marked cell proliferation and TUNEL detected cell apoptosis were reduced in S100a4-/- mice compared with WT mice after LPS treatment, indicating that S100A4 promotes both cell proliferation and cell apoptosis in epididymitis. Overall, these results demonstrate that S100A4 promotes the progression of LPS-induced epididymitis and facilitates a decline in sperm vitality, and its function may be related to the process of cell proliferation and apoptosis during inflammation.

4.
Aesthetic Plast Surg ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919624

RESUMO

BACKGROUND: Diameters greater than 1.5 mm are considered one of the generally accepted criteria for utilizing superficial epigastric artery (SIEA) flaps for breast reconstruction. However, this standard fails to consider individual differences among patients or deep inferior epigastric perforator (DIEP) perfusion of the same angiosome as the SIEA. This study combined the SIEA system with the DIEP system and explored the relationship between the two systems and body mass index (BMI) to theoretically provide a reference for flap choice in the preoperative surgical plan. METHODS: This study analysed preoperative computed tomography angiography (CTA) data from patients who received systematically postoperative treatment for unilateral breast cancer and were scheduled for breast reconstruction from 2013 to 2018 in our centre. All patients included had no past medical history that might have influenced the diameter of the SIEA, and their CTA data showed the presence of SIEA. RESULTS: Twenty-five females with a mean BMI of 23.6 ± 3.3 kg/m2 were included. A total of 30 hemi-abdomens identified with the SIEA were assessed. The measured mean diameter of the SIEA was 1.63 ± 0.55 mm, showing a highly linear correlation with BMI (r = 0.73, p < 0.001), while the maximum diameter of the deep inferior epigastric perforator (DIEPmax) and the number of dominant perforators originating from the deep inferior epigastric artery (DIEA) were not related to BMI. It was analysed from the equation between the calibre of the SIEA and BMI that when the BMI was greater than or equal to 24 kg/m2, the minimum diameter of the SIEA was at least 1.5 mm; when the BMI was 25 kg/m2, the diameter of the SIEA was, at most, 2.0 mm. Based on the linear correlation described above, we proposed that if the diameter of the SIEA was greater than or equal to 2.0 mm, a BMI ≥ 25 kg/m2 could be fully guaranteed. In terms of the advantageous single pedicle for reconstruction, the ratio of the SIEA diameter to DIEPmax (SIEA/DIEPmax) showed a significant linear correlation with BMI (r = 0.82, p < 0.001), and when the BMI was greater than or equal to 25 kg/m2, the lower limit of its predicted value was above 1.0; in other words, the SIEA diameter was advantageous compared with DIEPmax for the use of a single pedicle. In terms of perfusion, the SIEA system was positively correlated with BMI (p < 0.001), while the DIEP system was not. The difference in perfusion level between the SIEA and DIEP systems showed a positive correlation with BMI (p = 0.001), while the sum of the two systems only tended to be correlated, without statistical significance (p = 0.06). CONCLUSIONS: For patients with a BMI ≥ 25 kg/m2 or an SIEA diameter ≥ 2.0 mm, application of an SIEA flap is theoretically a preferable choice in preoperative surgical planning for breast reconstruction. And the patients should meet two conditions: the first one is the absence of past medical history that might potentially influence the diameter of the SIEA; the second is the presence of the SIEA, which has already been shown by the preoperative imaging data. Through perfusion-related studies, we propose that the SIEA is likely a compensatory vessel that is inclined to present in people with larger BMIs. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

5.
J Hazard Mater ; 385: 121584, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31761650

RESUMO

Residues of bisphenol A (BPA) are ubiquitously detected in the surface water due to its widespread usage. This study systematically investigated the dissipation and kinetics of BPA under simulated hydrolysis, direct and indirect photolysis, bacterial degradation, microbial degradation and natural attenuation in microcosm. Structural equation modeling (SEM) by using partial least square method in path coefficient analysis suggested that the microbial degradation was the major factor involved in the natural attenuation of BPA. The potential transformation products were identified by using liquid chromatography high-resolution mass spectrometry (LC-HRMS) and stable isotope tracing technique by simultaneous performing gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) and gas chromatography mass spectrometry (GC-MS). A total of fourteen including three novel transformation products of BPA were identified to indicate five possible pathways. An increased yield of labeled (δ13C) CO2 and detection of 13C-labeled phospholipid fatty acids (PLFAs) indicated the mineralization of BPA and possible utilization of BPA or its transformation products by microbes for cellular membrane synthesis, respectively.

6.
J Clin Pathol ; 73(3): 139-146, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31586937

RESUMO

AIMS: To unveil the role of EI2BL in non-small cell lung cancer (NSCLC) and the relationship between expression of EI2BL and the prognosis of patients with NSCLC. METHODS: Immunohistochemistry (IHC), western blot analysis, immunofluorescence and real-time quantitative PCR (RT-qPCR) were used to evaluate EI2BL protein and mRNA levels in NSCLC and corresponding peritumour tissues. Cell Counting Kit-8, transwell assay and wound healing assay were used to analyse the abilities of cell proliferation, invasion and migration. In addition, the analysis of epithelial-mesenchymal transition (EMT) markers was also assessed by western blot analysis, RT-qPCR and immunofluorescence. Tissue micro-array analysis of 200 NSCLC cases was used to assess the relationship between EI2BL expression and clinicopathological characteristics. Moreover, the prognostic role of EI2BL in 200 patients with NSCLC was evaluated by Cox regression models and Kaplan-Meier methods. RESULTS: Elevated EI2BL expression was more common in NSCLC tissues than paired peritumour tissues in both mRNA and protein level. EI2BL promoted the proliferation, invasion and migration of NSCLC cells. In addition, aberrant EI2BL expression might modulate the expression of key molecules of EMT by ERK1/2 signal pathway. The expression of EI2BL was significantly associated with tumour stage, lymph node metastasis and tumour size. Moreover, higher expression of EI2BL in patients with NSCLC had a poor overall survival rate. CONCLUSIONS: Our study illustrated that elevated expression of EI2BL promoted NSCLC cell proliferation, migration and invasion and EI2BL overexpression may be a reliable biomarker of poor prognosis.

8.
Biomed Pharmacother ; 121: 109610, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31710894

RESUMO

Bromopyruvate (3-BrPA) is a glycolysis inhibitor that has been reported to have a strong anti-tumour effect in many human tumours. Several studies have reported that 3-BrPA could inhibit glioma progression; however, its role on the interstitial cells in the glioma microenvironment has not been investigated. In previous studies, we found that in the glioma microenvironment, glioma stem cells can induce the malignant transformation of macrophages and dendritic cells. In this study, we focused on the effects of 3-BrPA on malignantly transformed macrophages and dendritic cells. First, we found that 3-BrPA inhibited the proliferation of malignantly transformed macrophages and dendritic cells in a dose-dependent and time-dependent manner. Further study indicated that 3-BrPA significantly decreased extracellular lactate and inhibited the clone formation, migration and invasion of malignantly transformed macrophages and dendritic cells. Using an online database and a series of experiments, we demonstrated that 3-BrPA inhibits the malignant progression of malignantly transformed macrophages and dendritic cells via the miR-449a/MCT1 axis. These findings built experimental basis for new approach against glioma.

9.
J Gynecol Oncol ; 31(1): e8, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31788998

RESUMO

OBJECTIVE: The purpose of this study was to analyze the impact of surgery of primary sites on stage IVB cervical cancer patients from a population-based database, the Surveillance, Epidemiology and End Results (SEER). METHODS: Propensity score matching was performed to minimize heterogeneity in patient between with-surgery group and without-surgery group. Clinicopathological characteristics were compared using the χ² or Fisher's exact test. Survival analysis included the Kaplan-Meier method, log-rank test, and Cox proportional hazards model. RESULTS: Between 2010-2015, a total of 1,139 International Federation of Gynecology and Obstetrics (FIGO) stage IVB cervical cancer patients receiving chemoradiotherapy (CRT) were included in this retrospective study. Within post-matching cohort, the median duration of overall survival (OS) in stage IVB cervical cancer patients receiving CRT was 22 months. The overall 5-year survival rate was 25.7%. The increasing American Joint Committee on Cancer T stage (T1 vs. T2, p=0.033, hazard ratio [HR]=1.79, 95% confidence interval [CI]=1.05-3.05; T1 vs. T3, p=0.003, HR=2.20, 95% CI=1.31-3.67; T1 vs. T4, p=0.037, HR=2.75, 95% CI=1.06-7.12) and visceral metastasis (with vs. without, p=0.038, HR=1.60, 95% CI=1.03-2.49) was reported as independent risk factors of OS. Surgery of primary sites combined with CRT tended to prolong the survival of stage IVB cervical cancer patients (p<0.001, HR=0.36, 95% CI=0.21-0.61) compared with CRT, especially for patients without visceral metastasis (p=0.005, HR=0.31, 95% CI=0.14-0.70). CONCLUSIONS: In conclusion, patients with stage IVB cervical cancer may achieve their best outcomes through CRT combined with surgery of primary sites. However, it deserves large scale prospective clinical trials to confirm.

10.
Environ Sci Pollut Res Int ; 27(7): 7515-7525, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31885059

RESUMO

Shengjin Lake wetland reserve is an important habitat for the winter cranes of our country, and the change of land use structure in the area have had a vital influence on the winter cranes and their habitat. The TM remote sensing images of 1986-2015 years were selected in this paper, and the land use change model and gray relational analysis model were used to analyze the effect of land use degree on the habitat of the winter crane and correlation degree between cranes and land use of Shengjin lake wetland. The land use transformation method was employed to analyze the transfer of the habitat of cranes and the relationship between the size of the cranes habitat and the number of populations. The results showed that the degree of land use change fluctuated greatly in different periods, and comprehensive index of land use degree between 220 and 260, also the land use was based on woodland, grassland, and water and their effect on the habitat was limited; the marsh land had the highest retention rate among the cranes habitat being 34.44%. While the reed flat had the lowest rate, only 15.36%, and the reed breach land was mainly transferred to marsh and dry land, 23.22% and 18.16%, respectively. The mud was mainly transferred to water and farmland, respectively, for 31.79% and 27.75%; except the period from 2011 to 2015, the change of habitat area was basically consistent with the change of the number of cranes.

11.
Sci Rep ; 9(1): 18660, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31796858

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
J Sex Res ; : 1-12, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829900

RESUMO

Adolescence is a critical life stage when individuals further consolidate their gender role concepts, develop sexual beliefs, and likely begin to experiment with sexual behaviors. While there have been numerous studies on adolescents' gender role attitudes, sexual beliefs, and sexual behaviors, the bulk of this research has been based on Western samples. The current study aimed to expand our knowledge of adolescents' gender and sexuality by examining gender role attitudes, sexual beliefs, and sexual behaviors in an urban sample (n = 613) and a rural sample (n = 408) from China. Adolescent boys reported stronger identification with the negative male role, less sexual guilt, and stronger sexual intention than their female counterparts. Compared to the urban sample, adolescents in the rural sample were more likely to endorse both negative and positive male roles, hold the sexual double standard, and experience sexual guilt. Regression analyses yielded significant interaction effects between sex and negative male role on sexual guilt and sexual intention, suggesting that the negative male role was differentially associated with sexual guilt and sexual intention in boys versus in girls. Moreover, the negative male role was the only significant predictor of sexual behavior. Cultural implications of these findings were discussed.

13.
ACS Appl Mater Interfaces ; 11(49): 45922-45929, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31718160

RESUMO

The pursuit of high-performance photodetectors functioning in the solar-blind spectrum is motivated by both scientific and practical applications ranging from secure communication, monitoring, sensing, etc. In particular, the fabrication of heterojunctions based on the wide band gap semiconductors has emerged as an attractive strategy to promote the high-efficient photogenerated electron/hole pair separation. However, the precisely controlled growth of heterojunctions remains a huge challenge. The lattice mismatch leads to the formation of defects and/or dislocations at the interface, deteriorating the performance of devices and limiting their envisioned applications. Here, we demonstrate a simple one-step growth of amorphous/crystalline Ga2O3 phase junctions by using sputtering technique, yielding a large responsivity of 0.81 A/W, a superior photo-to-dark current ratio over 107, and an ultrahigh response speed of ∼12 ns. Compared to the previous reported solar-blind photodetectors, the obtained detectivity ≈ 5.67 × 1014 Jones is increased by 2 orders of magnitude. Such excellent photoresponse characteristics can be understood by the interfacial built-in field-promoted electron/hole pair separation for the amorphous/crystalline Ga2O3 phase junctions. Our results provide a novel path toward realizing high-performance optoelectronics functioning in the solar-blind spectrum.

14.
Vet Microbiol ; 239: 108496, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31767077

RESUMO

Duck circovirus (DuCV) has a small, single-stranded circular DNA genome of approximately 1.99 kb. Through a genome sequence analysis using the dottup program, we found that a quadruple tandem repeat sequence (QTR) in the intergenic region between the rep and cap genes of the DuCV genome, but not in other circoviruses. The QTR was also substantially different and evolutionarily conserved in the genotype 1 and 2 DuCV strains. Furthermore, a luciferase reporter assay demonstrated that QTR functioned as a downstream sequence element (DSE) of polyadenylation signals to enhance mRNA stability, which was dependent on four copies but not the QTR direction. Cap and Rep expression derived by subgenomic constructs also revealed a critical role of QTR in regulating viral gene expression. Finally, a reverse genetic study of a DuCV-based minicircle DNA technique found that a deletion of QTR induced a significant deficiency in viral genes transcription and replication. Our findings were the first to report that QTR only exists in the DuCV genome and serves as a novel molecular marker of DuCV genotyping, and has revealed its crucial biological function in regulating viral gene expression.


Assuntos
Circovirus/genética , Regulação Viral da Expressão Gênica/genética , Sequências de Repetição em Tandem/genética , Animais , Infecções por Circoviridae/virologia , DNA Viral/genética , Genoma Viral/genética , Genótipo , Estabilidade de RNA
15.
Onco Targets Ther ; 12: 6797-6811, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686838

RESUMO

Breast cancer (BC) is the most commonly diagnosed cancer among women and the leading cause of cancer death. Despite the advent of numerous diagnosis and treatment methods in recent years, this heterogeneous disease still presents great challenges in early diagnosis, curative treatments and prognosis monitoring. Thus, finding promising early diagnostic biomarkers and therapeutic targets and approaches is meaningful. Metabolomics, which focuses on the analysis of metabolites that change during metabolism, can reveal even a subtle abnormal change in an individual. In recent decades, the exploration of cancer-related metabolomics has increased. Metabolites can be promising biomarkers for the screening, response evaluation and prognosis of BC. In this review, we summarized the workflow of metabolomics, described metabolite signatures based on molecular subtype as well as reclassification and then discussed the application of metabolomics in the early diagnosis, monitoring and prognosis of BC to offer new insights for clinicians in breast cancer diagnosis and treatment.

16.
Front Oncol ; 9: 956, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31637211

RESUMO

Mining cancer-omics databases deepens our understanding of cancer biology and can lead to potential breakthroughs in cancer treatment. Here, we propose an integrative analytical approach to reveal across-cancer expression patterns and identify potential clinical impacts for genes of interest from five representative public databases. Using ribonucleotide reductase (RR), a key enzyme in DNA synthesis and cancer-therapeutic targeting, as an example, we characterized the mRNA expression profiles and inter-component associations of three RR subunit genes and assess their differing pathological and prognostic significance across over 30-types of cancers and their related subtypes. Findings were validated by immunohistochemistry with clinical tissue samples (n = 211) collected from multiple cancer centers in China and with clinical follow-up. Underlying mechanisms were further explored and discussed using co-expression gene network analyses. This framework represents a simple, efficient, accurate, and comprehensive approach for cancer-omics resource analysis and underlines the necessity to separate the tumors by their histological or pathological subtypes during the clinical evaluation of molecular biomarkers.

17.
Cell Death Dis ; 10(11): 799, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641102

RESUMO

Following publication of this article [1], it was realized that an error was made in typesetting which resulted in a change in the ordering of the last two authors. The correct ordering of the authors for the paper is as follows:Mao Zhang, Shihai Liu, Mei-Sze Chua, Haoran Li, Dingan Luo, Sheng Wang, Shun Zhang, Chuandong Sun (*) & Bing Han (*)[(*) indicates corresponding author]An amendment to this paper has been published and can be accessed via a link at the top of the paper.

18.
19.
Beilstein J Org Chem ; 15: 2069-2075, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31501675

RESUMO

The Pd-catalyzed C-H bond functionalization of lilolidine was investigated. The use of a palladium-diphosphine catalyst associated to acetate bases in DMA was found to promote the regioselective arylation at α-position of the nitrogen atom of lilolidine with a wide variety of aryl bromides. From these α-arylated lilolidines, a second arylation at the ß-position gives the access to α,ß-diarylated lilolidines containing two different aryl groups. The one pot access to α,ß-diarylated lilolidines with two identical aryl groups is also possible by using a larger amount of aryl bromide. The synthesis of 5,6-dihydrodibenzo[a,c]pyrido[3,2,1-jk]carbazoles from lilolidine via three successive direct arylations is also described. Therefore, this methodology provides a straightforward access to several lilolidine derivatives from commercially available compounds via one, two or three C-H bond functionalization steps allowing to tune their biological properties.

20.
J Colloid Interface Sci ; 556: 680-688, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31499439

RESUMO

HYPOTHESIS: The surface charge of gallium nitride (GaN) in contact with solution is controlled by pH via surface protonation and deprotonation, similar to silica. Ionic surfactants adsorb on surfaces via electrostatic and hydrophobic interactions and can be utilized to reflect the surface charge of GaN. EXPERIMENTS: The surface charge properties of Ga-polar GaN in solution were probed as a function of pH using atomic force microscopy (AFM). AFM soft-contact images and force curves were used to study the pH-dependent adsorption of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and anionic surfactant sodium dodecylsulfate (SDS) on GaN surfaces. To further confirm the AFM results, GaN/AlGaN/GaN heterostructure-based ion sensing devices were used to measure the surfactant adsorption over the same pH range. FINDINGS: SDS aggregates adsorb on GaN below pH 2.75 while CTAB aggregates adsorb above pH 10. This shows that the GaN surface carries substantial net positive charge at low pH, and negative charge at high pH. There is no clear SDS or CTAB adsorption on the GaN surface between pH 3 and 9.75, which indicates the surface is weakly charged. GaN/AlGaN/GaN heterostructure-based devices confirm these results, and demonstrate the utility of these devices for measuring surfactant adsorption.

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