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1.
Ann Palliat Med ; 9(1): 82-89, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32005066

RESUMO

BACKGROUND: Younger patients who underwent vitrectomy for proliferative diabetic retinopathy (PDR) display more aggressive nature distinguished from the older patients. Preoperative anti-VEGF therapy has been widely used as an adjunct for PDR surgery. However, the effect of anti-VEGF administration in young diabetics has rarely been evaluated in previous studies. The purpose of this study was to evaluate the effects of ranibizumab pretreatment on vitrectomy surgery in young patients with PDR. METHODS: This was a prospective nonrandomized comparative study. Young patients (<40 years old) undergoing diabetic vitrectomy with or without ranibizumab pretreatment (25 eyes in each group) were analyzed in this study. The use of the drug was determined by the patients' own preference. The two surgical groups were matched according to a complexity score. Intravitreal injection of ranibizumab (IVR) was performed 3-5 days prior to the vitrectomy surgery in the IVR group. Intraoperative records including total surgical time, intraoperative bleeding, the use of endodiathermy, the frequency of relaxing retinotomies, the incidence of iatrogenic retinal breaks, and the use of perfluorocarbon liquid (PFCL) and silicone oil tamponade, and postoperative indices regarding recurrent vitreous hemorrhage (VH), neovascular glaucoma (NVG), recurrent retinal detachment, and visual outcome were evaluated between the two groups. All patients were followed up for one year after surgery. RESULTS: In young PDR patients, the severity of intraoperative bleeding was significantly lower in the IVR group than in the control group (P=0.04). The total surgical time was shorter in the IVR group than in the control group. However, the rate of relaxing retinotomy, the incidence of iatrogenic retinal breaks and the use of PFCL and silicone oil tamponade were not affected by IVR pretreatment but affected by the complexity score of the case. Early postvitrectomy hemorrhage occurred less frequently in the IVR group than in the control group (P<0.001), Early visual recovery was better in the IVR group than in the control group (P=0.03). However, there were no significant differences in the development of late recurrent VH, NVG, recurrent retinal detachment, and final visual outcome. CONCLUSIONS: IVR pretreatment is a safe and effective adjunct to vitrectomy in reducing intraoperative and early postvitrectomy bleeding and should be suggested in young PDR patients. However, IVR does not reduce the incidence of intraoperative and late postoperative complications in these patients. The risk of iatrogenic retinal breaks and silicone oil use are closely correlated with the complexity score of the surgical cases.

2.
BMC Musculoskelet Disord ; 21(1): 102, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32059654

RESUMO

BACKGROUND: The incidence of insufficiency fracture (IF) at femoral neck is low, accounting for about 5% of all insufficiency fractures, and IF at bilateral femoral neck is less common with more occurrence in athlete or serviceman. With the aging of populations, more cases of bilateral femoral neck IF have occurred recently, while the standard clinical treatment still remains lacking due to the complexity of these patients. CASE PRESENTATION: A 55-year-old male patient complained pain in his bilateral hip, with no history of trauma, glucocorticoid hormone consumption or radiotherapy, and imaging examination revealed fracture nonunion and shortening in his left femoral neck, and double fracture line on the right femoral neck. The patient received a cementless THA for the left femoral neck fracture and conservative treatment for the right side, followed by Elcatonin injection and oral administration of Carbonate D3 Granules. After 4 months of fellow-up, the patient presented improved functional scorings in bilateral hip joints, with no signs of prothesis infection or loosening. CONCLUSION: We present a rare case of bilateral femoral neck IF in a middle-aged male and the treatment is successful. The timely CT and MRI examinations of bilateral hip joints for patients was necessary for orthopedists to select proper therapeutic regimen. In addition, the choice for therapeutic regimen of bilateral femoral IF should not only be based on the professional judgement of orthopedists, but also on the wishes of patients.

3.
Food Chem ; 315: 126300, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32018077

RESUMO

In this study, a novel sensor fabricated with compactly arranged gold nanoparticles (AuNPs) templated from mesoporous silica film (MSF) via air-water interface has been confirmed as a promising surface-enhanced Raman scattering (SERS) substrate for detecting trace levels of 2,4-dichlorophenoxyacetic acid (2,4-D), pymetrozine and thiamethoxam. The densely arranged AuNPs@MSF had an average AuNPs size of 5.15 nm with small nanogaps (<2nm) between AuNPs, and exhibited a high SERS performance. SERS spectra of pesticides were collected after their adsorption on the AuNPs@MSF. The results showed that the concentration of 2,4-D, pymetrozine and thiamethoxam gave a good linear relationship with SERS intensity. Moreover, the designed SERS-based sensor (AuNPs@MSF) was stable for 3 months with ca. 3% relative standard deviation (RSD) and was applied successfully for the analysis of 2,4-D extraction from both environmental and food samples. The proposed SERS-based sensor was further validated by HPLC and showed satisfactory result (p > 0.05).

4.
Cancer Lett ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32061752

RESUMO

Drug resistance is a big problem in cancer treatment and one of the most prominent mechanisms underlain is overexpression of ATP-binding cassette (ABC) transporters, particularly ABCB1, ABCC1 and ABCG2. Inhibition of ABC transporters is an important approach to overcome drug resistance. The inositol-requiring enzyme 1α (IRE1α), an arm of unfolded protein response (UPR), splices XBP1 mRNA to generate an active transcription factor XBP1s. UPR is implicated in drug resistance. However, the underlying mechanism is unclear. We found that the anticancer drugs such as 5-fluorouracil (5-FU) activated the IRE1α-XBP1 pathway to induce the expression of ABCB1, ABCC1 and ABCG2 in colon cancer cells. Inhibition of IRE1α RNase activity with small molecule 4µ8c suppressed the drug-induced expression of these ABC transporters and sensitized 5-FU-resistant colon cancer cells to drug treatment. In vivo xenograft assay indicates that administration of 4µ8C substantially enhanced the efficacy of 5-FU chemotherapy on 5-FU-resistant colon cancer cells. These results suggest that IRE1α-targeting might be a strategy to cope with drug resistance of colon cancer.

5.
Poult Sci ; 99(2): 869-878, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32036982

RESUMO

Ammonia (NH3) emission from nondigested nutrients in poultry creates additional adverse environmental impacts on soil, water, air, and health. Mitigating NH3 emission has become vital for the poultry industry to remain sustainable. As the presence of large particles in the feed stimulates the broiler gizzard to retain ingesta in the gastrointestinal tract longer and improve digestive efficiency, the inclusion of large particles in feed may lead to less nitrogen (N) and moisture content (MC) in feces such that lower NH3 production would be expected. This chamber study investigated the effects of dietary coarse corn (CC) inclusion on broiler live performance, litter characteristics, and NH3 emission. One hundred eighty female broilers (Ross 344 × 708 strains) at day 21 were randomly placed in 6 chambers with 2 dietary treatments (0% CC and 50% CC), with 3 chambers per treatment and 30 birds per chamber for 3 wks. The results showed that the 50% CC inclusion (1) decreased broiler feed intake and BW without affecting mortality-adjusted feed conversion ratio from day 21 to 42; (2) increased gizzard weight and decreased proventriculus weight; (3) decreased N content and MC in litter; and (4) decreased NH3 concentrations in the chambers, as well as NH3 emission from the chambers. Dietary CC inclusion could be an effective way to mitigate broiler litter N content and MC as well as NH3 emission.

6.
Food Funct ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003387

RESUMO

Alzheimer's disease, characterized by neuroinflammation and beta-amyloid protein plaques, is a memory-threatening neurodegenerative disease with no effective treatment. Here, the effect of bilberry anthocyanins (BA) on cognitive functions was evaluated using APP/PSEN1 transgenic Alzheimer's disease model mice and their WT littermates. Our results revealed that BA appreciably improves learning and memory abilities and reverses defects to cognitive functions in APP/PSEN1 mice. Furthermore, BA reverses brain, liver and kidney damage caused by Alzheimer's disease, with no significant changes in oxidative stress and lipid metabolism-related indicators. In addition, BA decreases serum and brain lipopolysaccharide (LPS) levels and increases fecal short-chain fatty acid content. Immunofluorescence and RT-PCR analysis results showed that BA fully activates the microglia and astrocytes, downregulates the expression of inflammatory factors (TNF-α, NF-Kß, IL-1ß, IL-6, COX-2, iNOS and CD33) and chemokine receptor CX3CR1, and upregulates the expression of microglia homeostatic factors (TREM2 and TYROBP) and Toll-like receptors (TLR2 and TLR4). Moreover, western blot analysis revealed that BA significantly upregulates the expression of synaptic and phagocytotic function-related proteins (CD68, synaptophysin and IRF7) in APP/PSEN1 mice. Altogether, we show for the first time that BA consumption reverses Alzheimer's disease-induced cognitive disfunction, decreases hippocampal neuroinflammatory responses, and induces phagocytosis of microglia to beta-amyloid protein plaques by regulating the CD33/TREM2/TYROBP signaling pathway in microglia.

7.
Aging (Albany NY) ; 122020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32012119

RESUMO

The prevalence of smoking is significantly higher in persons with schizophrenia (SCZ) than in the general population. However, the biological mechanisms of the comorbidity of smoking and SCZ are largely unknown. This study aimed to reveal shared biological pathways for the two diseases by analyzing data from two genome-wide association studies with a total sample size of 153,898. With pathway-based analysis, we first discovered 18 significantly enriched pathways shared by SCZ and smoking, which were classified into five groups: postsynaptic density, cadherin binding, dendritic spine, long-term depression, and axon guidance. Then, by using an integrative analysis of genetic, epigenetic, and expression data, we found not only 34 critical genes (e.g., PRKCZ, ARHGEF3, and CDKN1A) but also various risk-associated SNPs in these genes, which convey susceptibility to the comorbidity of the two disorders. Finally, using both in vivo and in vitro data, we demonstrated that the expression profiles of the 34 genes were significantly altered by multiple psychotropic drugs. Together, this multi-omics study not only reveals target genes for new drugs to treat SCZ but also reveals new insights into the shared genetic vulnerabilities of SCZ and smoking behaviors.

8.
Biomed Pharmacother ; 125: 109933, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32036215

RESUMO

Airway remodeling is a key feature of asthma. Extracellular matrix synthesis and vascular remodeling respectively regulated by transforming growth factor (TGF-ß1) and vascular endothelial growth factor (VEGF), are important for the airway remodeling. This study aimed to investigate the effect of Soufeng Yuchuan (SFYC) decoction, a Traditional Chinese Medicine, on airway remodeling and expression of VEGF and TGF-ß1 in asthma model rats. A rat model of asthma was induced by ovalbumin (OVA) treatment. The results showed that SFYC decoction improved general conditions and reduced the damage in lung tissues in asthma model rats. Furthermore, SFYC decoction significantly reduced the OVA-induced levels of VEGF and TGF-ß1 in sera and in bronchoalveolar lavage fluid. Moreover, SFYC decoction decreased the OVA-induced VEGF mRNA and protein levels in lung tissues in asthma model rats. Interestingly, SFYC with high dose was more potent in reducing TGF-ß1 level in rat sera and BALF than dexamethasone (positive control). In summary, SFYC decoction effectively mitigates lung damage in OVA-induced asthma model rats, which was associated with inhibition of VEGF and TGF-ß1.

9.
Opt Lett ; 45(4): 968-971, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058519

RESUMO

The spectrum overlapping of the radiative power between magnetic and electric dipole moments in nanoparticles can be used to realize unidirectional light scattering, which is promising for various kinds of applications. Nevertheless, it is still challenging to achieve such overlapping in a broadband manner. Herein, we propose that the combination of a genetic algorithm, Maxwell's equations, and electromagnetic multipole expansion can be used to design a nanoparticle that supports resonant broadband forward light scattering. Microwave experiments are performed to demonstrate our numerical results. The proposed method is quite general, and it can be straightforwardly generalized to design functional unidirectional scatters.

10.
Ophthalmic Res ; : 1-12, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32023612

RESUMO

PURPOSE: To analyze the relationships between choroidal thickness (CT) and diabetes mellitus (DM), diabetic retinopathy (DR), and DR severity in community residents diagnosed with type 2 DM, and to explore whether CT can improve the discriminatory ability of other risk factors to predict the incidence of DR. METHODS: A total of 1,250 type 2 DM residents and 1,027 healthy controls in Xinjing community of Shanghai participated a cross-sectional survey of eye diseases in 2016. CT was measured using swept-source optical coherence tomography. DR was classified according to the 2002 international clinical classification of DR. A total of 537 subjects with type 2 DM without DR at the 2016 survey were followed up in 2018 to investigate the 2-year incidence of DR. Receiver operating characteristic curve analysis was used to test the accuracy of different indicators in predicting the onset of DR. RESULTS: The central CT of the control, no DR, mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR, and PDR groups were 223.40, 216.22, 213.57, 211.91, 178.47, and 168.15 µm, respectively (p for trend <0.001), and the average CT (ACT) were 197.83, 186.94, 182.03, 178.00, 156.91, and 136.72 µm respectively (p for trend <0.001). Body mass index (BMI), DM duration, fasting blood glucose, glycosylated hemoglobin (HbA1C), and ACT were risk factors for 2-year DR incidence. For the onset of DR, as predicted by ACT, after tenfold cross validation the average area under the curve was 0.55 (p = 0.048). Addition of ACT did not improve the discriminatory ability of DM duration, BMI, glucose and HbA1C on the incidence of DR (Z = 0.48; p = 0.63). CONCLUSIONS: As the severity of DR increased, the CT of community type 2 DM patients showed a significant downward trend compared with the healthy controls. Thinner ACT was found to be a risk factor for DR incidence, but it did not improve the discriminatory ability of other risk factors to predict the incidence of DR.

11.
Dermatol Ther ; : e13265, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32052534
12.
Aging (Albany NY) ; 12(2): 1792-1807, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32003755

RESUMO

The aim was to determine whether the neuroprotective effect of SIRT1 in Alzheimer's disease (AD), due to inhibition of aggregation of the ß-amyloid peptide (Aß), involves activation of α7 nAChR. In present study, four-month-old APP/PS1 mice were administered resveratrol (RSV) or suramin once daily for two months, following which their spatial learning and memory were assessed using the Morris water maze test. Deposits of Aß in vivo were detected by near-infrared imaging (NIRI) and confocal laser scanning. SH-SY5Y/APPswe cells were treated with RSV, suramin, U0126 or methyllycaconitine (MLA). Levels of proteins and mRNA were determined by Western blotting and qRT-PCR, respectively. The results show that activation of SIRT1 improved their spatial learning and memory and reduced the production and aggregation of Aß in the hippocampus and cerebral cortex; whereas inhibition of SIRT1 had the opposite effects. In addition, activation of SIRT1 increased the levels of both α7 nAChR and αAPP in the brains these animals. Finally, activation of SIRT1 elevated the levels of pERK1/2, while inhibition of ERK1/2 counteracted the increase in α7 nAChR caused by RSV. These findings indicate that neuroprotection by SIRT1 may involve increasing levels of α7 nAChR through activation of the MAPK/ERK1/2 signaling pathway.

13.
Clin Sci (Lond) ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32065214

RESUMO

Cancer-derived exosomal miRNAs play an important role in the development of metastasis, but the effects and underlying mechanisms remain unclear. In the present study, we investigated the miRNA expression profiles of 5 paired serum exosomal samples from metastatic colorectal cancer (mCRC) and non-mCRC patients via RNA sequencing. After we evaluated the differentially expressed miRNAs in 80 CRC patients, miR-106b-3p was selected as a metastasis-associated miRNA of CRC. We showed that the expression level of serum exosomal miR-106b-3p was significantly higher in CRC patients with metastasis than those without metastasis. Additionally, high serum exosomal miR-106b-3p expression in patients was correlated with a poor prognosis. Coculture of low-metastatic CRC cells with high-metastatic CRC cell-derived exosomes promoted cell migration, invasion, and epithelial to mesenchymal transition (EMT), which was caused by the transport and transduction of miR-106b-3p in vitro. Moreover, exosomal miR-106b-3p promoted lung metastasis of CRC cells in vivo. In addition, we demonstrated that miR-106b-3p regulated metastasis by targeting deleted in liver cancer-1 (DLC-1). A negative correlation was also identified between miR-106b-3p and DLC-1 expression in human CRC tumour tissues and in mouse lung metastatic lesions. Collectively, our study indicated that metastasis-associated miR-106b-3p from serum exosomes could be used as a potential prognostic biomarker and therapeutic target for CRC patients.

14.
Sci Rep ; 10(1): 989, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969644

RESUMO

Hand, foot, and mouth disease (HFMD) is a common childhood illness caused by enteroviruses. We analyzed the pathogenic characteristics of HFMD in Shaanxi province, China, during 2010-2016. Clinical samples were collected from HFMD cases. Real-time PCR and RT-PCR were used to identify the enterovirus(EVs) serotypes. Viral RNA sequences were amplified using RT-PCR and compared by phylogenetic analysis. Descriptive epidemiological methods were used to analyze. A total of 16,832 HFMD positive cases were confirmed in the laboratory. EV-A71 and CV-A16 were the main pathogens in 2010. EV-A71 was the dominant pathogen in the periods of 2011 to 2012 and 2014, 2016. In 2013 and 2015, other EVs increased greatly, in which CV-A6 was the predominant pathogen. EV-A71 was more frequently detected in deaths and severe cases. Phylogenetic analysis revealed that EV-A71 belonged to the C4a evolution branch of C4 sub-genotype and CV-A16 belonged to the B1a or B1b evolution branch of B1 sub-genotype, whereas CV-A6 strains were assigned to D2 or D3 sub-genotype. The pathogen spectrum of HFMD has changed in 7 years, and the major serotypes EV-A71, CV- A16 and CV- A6 alternated or co-circulated. Long-term surveillance and research of EVs should be strengthened for the prevention and control of HFMD.

15.
Plant Biotechnol J ; 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31975524

RESUMO

Kenaf is an annual crop that is widely cultivated as a source of bast (phloem) fibres, the phytoremediation of heavy metal-contaminated farmlands and textile-relevant compounds. Leaf shape played a unique role in kenaf improvement, due to the inheritance as a single locus and the association with fibre development in typical lobed-leaf varieties. Here we report a high-quality genome assembly and annotation for var. 'Fuhong 952' with 1078 Mbp genome and 66 004 protein-coding genes integrating single-molecule real-time sequencing, a high-density genetic map and high-throughput chromosome conformation capture techniques. Gene mapping assists the identification of a homeobox transcription factor LATE MERISTEM IDENTITY 1 (HcLMI1) gene controlling lobed-leaf. Virus-induced gene silencing (VIGS) of HcLMI1 in a lobed-leaf variety was critical to induce round (entire)-like leaf formation. Candidate genes involved in cell wall formation were found in quantitative trait loci (QTL) for fibre yield and quality-related traits. Comparative genomic and transcriptome analyses revealed key genes involved in bast fibre formation, among which there are twice as many cellulose synthase A (CesA) genes due to a recent whole-genome duplication after divergence from Gossypium. Population genomic analysis showed two recent population bottlenecks in kenaf, suggesting domestication and improvement process have led to an increase in fibre biogenesis and yield. This chromosome-scale genome provides an important framework and toolkit for sequence-directed genetic improvement of fibre crops.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31977178

RESUMO

In this work, a single-layered graphene (SLG)/Au-nanoparticles (NPs)-based Love wave biosensor was prepared for detection of Staphylococcus aureus (S. aureus) gene sequence. Annealing process was proposed to obtain a larger-area interface with ssDNA. The sensitivity was verified by detecting S. aureus gene sequences with a linear detection ranging from 0-10 nmol/L, where the limit of detection (LOD) was only 12.4 pg/mL. The stable state of the biosensors based on SLG/Au NPs in liquid phase could be kept for more than 0.5 h (± 0.1°), and the specificity was verified by detecting non-complementary ssDNA, one/three-base mismatched ssDNA. The results of our study suggest that Love wave biosensor based on SLG/Au NPs hold great potential in clinical testing and diagnosis.

17.
Clin Cardiol ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31943264

RESUMO

BACKGROUND: Limited comparative data are available regarding catheter ablation (CA) of atrial fibrillation (AF) using second-generation cryoballoon (CB-2) vs radiofrequency (RF) ablation in elderly patients (>75-year-old). HYPOTHESIS: CB-2 ablation may demonstrate different outcomes compared with that using RF ablation for elderly patients with AF. METHOD: Elderly patients with symptomatic drug-refractory AF were included in the study. Pulmonary vein isolation was performed in all patients. RESULTS: A total of 324 elderly patients were included (RF: 176, CB-2:148) from September 2016 to April 2019. The CB-2 was associated with shorter procedure time and left atrial dwell time (112.9 ± 11.1 vs 135.1 ± 9.9 minutes, P < .001; 53.7 ± 8.9 vs 65.1.9 ± 9.0 minutes, P < .001), but marked fluoroscopy utilization (22.1 ± 3.3 vs 18.5 ± 3.6 minutes, P < .001). Complications occurred in 3.3% (CB-2) and 6.2% (RF) of patients with no significant different (P = .307). The length of stay after ablation was shorter, but the costs were higher in the CB-2 group (1.94 vs 2.53 days, P < .001 and 91 132.6 ± 3723.5 vs 81 149.4 ± 6824.1 CNY, P < .001) compared to the RF group. Additionally, the rate of early recurrence of atrial arrhythmia was lower in the CB-2 group (14.2 vs 23.3%, P = .047), but the long-term success rate was similar between two groups. CONCLUSIONS: CB-2 is associated with shorter procedure time, left atrial dwell time, and length of stay after ablation, but its costs and fluoroscopy time are greater than the RF group. Moreover, the rate of complications and long-term success are similar between the two groups.

18.
Adv Mater ; : e1907077, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944433

RESUMO

2D metasurfaces have emerged as a paradigm-shifting platform for light management with considerable miniaturization and alleviated fabrication challenges than their 3D counterparts. However, the appearance of in-plane mirror symmetry and reduced dimensions impose fundamental restraints to advanced chiroptical responses and reconfiguration capabilities. Here, a new concept of Fano-enhanced circular dichroism by introducing a reconfigurable stereo metasurface, which possesses deformable out-of-plane twists that are readily achieved by a simple nano-kirigami fabrication method, is demonstrated. The stereo height and twisting geometries can be reproducibly controlled, providing a facile and automated fashion to tailor the distinct profiles of Fano resonances under circularly polarized incidence. As a result, a recorded high efficiency of circular dichroism generation per unit sample thickness is achieved with Fano resonances in opposite lineshapes. Leveraging this feature, large-range reconfiguration of circular dichroism at optical wavelengths is demonstrated through reversible compression of the stereo metasurfaces with a fiber tip. The studied stereo metasurface unfolds a new degree of freedom for advanced photonic applications in a quasi-flat optical platform, and the proposed concept of Fano-enhanced circular dichroism opens new venues to explore interesting fundamental phenomena of chiral optics.

19.
Chemosphere ; 246: 125792, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31918101

RESUMO

Metal-responsive transcription factor-1 (MTF-1) and metallothionein (MT) expression are involved in metal homeostasis and detoxification. Here, we characterized the structure and functions of mtf-1 and mt promoters in yellow catfish Pelteobagrus fulvidraco. Many important binding sites of transcriptional factors, such as heat shock promoter element (HSE) and metal responsive element (MRE), were predicted on their promoter regions. Cu did not significantly influence the activity of mtf-1 promoter, but Zn increased its promoter activity. Cu and Zn induced the increase of mt promoter activity. HSE site of mtf-1 promoter was the functional binding locus responsible for Zn-induced mtf-1 transcriptional activation. Zn and Cu induced transcriptional activation of mt gene through the MTF-1- and MRE-dependent pathway. Using primary hepatocytes of yellow catfish, we found that Cu and Zn induced the mt expression; Cu did not significantly influence the mRNA and total protein levels of MTF-1, but Zn up-regulated its mRNA and total protein expression. Both Zn and Cu treatment also up-regulated MTF-1 nuclear protein expression, which in turn increased the mt expression. Taken together, these findings delineated the transcriptional regulation of MT and MTF-1 under Zn or Cu treatments, and provided some mechanisms for the regulation of Cu and Zn homeostasis in vertebrates.

20.
Nanoscale ; 12(3): 1697-1706, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31894809

RESUMO

In this work, we demonstrate an interesting structural phase transition from SnS2/reduced graphene oxide to SnS/sulfur-doped graphene at a moderate calcination temperature of 500 °C under an inert atmosphere. It is discovered that SnS2 chemically bound to rGO with a weakened C-S bond is easier to break and decompose into SnS, whereas it is difficult for pure-phase crystalline SnS2 to experience phase transformation at this temperature. Moreover, the thin-layered structure of SnS2 and rGO is an important factor for the effective doping of the dissociated Sx into graphene. Density functional theory calculations also reveal the feasibility of the structural phase transition process. Morphology characterization shows that partial SnS maintains the original nanosheet structure (∼100 nm) and the others are decomposed into tiny nanoparticles (10-20 nm). A high S-doping amount reduces the irreversible lithium storage sites on graphene, and the first coulombic efficiency is as high as 81.7%. In addition, thin-layered and small-sized SnS can alleviate the structural damage caused by volume expansion and shrinkage; therefore, a high specific capacity of 893.9 mA h g-1 is retained after 100 cycles.

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