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1.
FEMS Microbiol Lett ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31950993

RESUMO

Ginsenoside Rg1 (GRg1) has neuroprotective effects on Alzheimer's disease (AD). The occurrence and progression of AD are closely related to gut microbiota. Few studies have learned the direct relationship between GRg1 and gut microbiota. In this study, we found an original way by using GRg1 in the AD model of tree shrews to research this relationship. Morris Water Maze and Immunohistochemistry were performed to test the cognition repairing function of GRg1 by tree shrews, 16S ribosomal RNA sequencing to explore the composition and abundance of gut microbiota. After GRg1 treatment, the result of Morris Water Maze showed the improvement of cognitive function, and Immunohistochemistry revealed the decrease of tau protein. Moreover, 16SrRNA sequencing results showed the abundance of Proteobacteria and Verrucomicrobia were significantly different, and Lactobacillaceae was significantly increased in GRg1 treatment group. It also showed the gut microbiome with middle and high dose of GRg1 was close to the normal group. In conclusion, this study suggests that GRg1 with middle and high dose may change the abundance of gut microbiota to improve AD, Proteobacteria and Verrucomicrobia are key microbiota. This is the first report that has ever studied the relationship between GRg1 and gut microbiota on tree shrews.

2.
Neurocrit Care ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907801

RESUMO

BACKGROUND: To date, cardiac dysfunction after traumatic brain injury (TBI) has not been consistent. In this study, we hypothesized that TBI may play a role in the development of new-onset cardiac dysfunction in healthy experimental rats. MATERIALS AND METHODS: Anesthetized healthy male Sprague-Dawley rats were divided into two groups: a sham-operated control group and a TBI group. The brain was injured with 2.4 atm percussion via a fluid percussion injury model. During the 120 min after TBI, we continuously measured brain parameters, including intracranial pressure (ICP) and cerebral perfusion pressure (CPP), and cardiac parameters, such as heart rate (HR), inter-ventricular septum dimension (IVSD), left ventricular internal dimension diastole (LVIDd), end-diastolic volume (EDV), ejection fraction (EF), fractional shortening (FS), and LV mass diastole (LVd mass) by cardiac echo. On days 1, 3, 7, and 14 after TBI, the brain damage volume was evaluated with triphenyltetrazolium chloride; the physiological parameters of the heart, including HR, IVSd, LVIDd, EDV, EF, FS, and LVd mass, were evaluated with cardiac echo; the morphology of cardiomyocytes was examined by hematoxylin and eosin (HE) and Masson trichrome staining; and the biomarkers of cardiac injury troponin I and B-type natriuretic peptide (BNP) were also examined. RESULTS: Compared to sham-operated controls, the TBI groups had higher ICP, lower CPP, and higher brain neuronal apoptosis and infarction contusion volume. The impact of TBI on heart function showed hyperdynamic response trends in IVSd, LVIDd, EDV, EF, FS, and LVd mass within 30 min after TBI; however, EF and FS exhibited eventual decreasing trends. Simultaneously, the values of the biomarkers troponin I and BNP were within normal limits, and HE and Mass trichrome staining revealed no significant differences between the sham-operated control group and the TBI group. CONCLUSIONS: Our results suggest that TBI due to 2.4 atm fluid percussion injury in healthy experimental rats may cause significant damage to the brain and affect the heart function as investigated by cardiac echo but not as investigated by HE and Masson trichrome stainings or troponin I and BNP evaluation.

3.
Transl Oncol ; 13(2): 423-440, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31911277

RESUMO

Tamoxifen is a successful endocrine therapy drug for estrogen receptor-positive (ER+) breast cancer. However, resistance to tamoxifen compromises the efficacy of endocrine treatment. In the present study, we identified potential tamoxifen resistance-related gene markers and investigated their mechanistic details. First, we established two ER + breast cancer cell lines resistant to tamoxifen, named MCF-7/TMR and BT474/TMR. Gene expression profiling showed that CXXC finger protein 4 (CXXC4) expression is lower in MCF-7/TMR cells than in MCF-7 cells. Furthermore, CXXC4 mRNA and protein expression are lower in the resistant cell lines than in the corresponding parental cell lines. We also investigated the correlation between CXXC4 and endocrine resistance in ER + breast cancer cells. CXXC4 knockdown accelerates cell proliferation in vitro and in vivo and renders breast cancer cells insensitive to tamoxifen, whereas CXXC4 overexpression inhibits cancer cell growth and increases tamoxifen sensitivity of resistant cells. In addition, we demonstrated that CXXC4 inhibits Wnt/ß-catenin signaling in cancer cells by modulating the phosphorylation of GSK-3ß, influencing the integrity of the ß-catenin degradation complex. Silencing the CXXC4 gene upregulates expression of cyclinD1 and c-myc (the downstream targets of Wnt signaling) and promotes cell cycle progression. Conversely, ectopic expression of CXXC4 downregulates the expression of these proteins and arrests the cell cycle in the G0/G1 phase. Finally, the small-molecule inhibitor XAV939 suppresses Wnt signaling and sensitizes resistant cells to tamoxifen. These results indicate that components of Wnt pathway that are early in response to tamoxifen could be involved as an intrinsic factor of the transition to endocrine resistance, and inhibition of Wnt signaling may be an effective therapeutic strategy to overcome tamoxifen resistance.

4.
Nat Commun ; 11(1): 170, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924790

RESUMO

Reduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97 ± 3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m-2; their maximum luminance is 4.5 × 104 cd m-2 (corresponding to an EQE of 5%); and, at 4000 cd m-2, they achieve an operational half-lifetime of 3.5 h.

5.
RNA Biol ; 17(1): 1-12, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31550975

RESUMO

As one type of the most common endogenous short noncoding RNAs (ncRNAs), microRNAs (miRNAs) act as posttranscriptional regulators of gene expression and have great potential biological functions in the physiological and pathological processes of various diseases. The role of miRNAs in renal fibrosis has also attracted great attention in the previous 20 years, and new therapeutic strategies targeting miRNAs appear to be promising. Some researchers have previously reviewed the roles of miRNA in renal fibrosis disease, but numerous studies have emerged over the recent 5 years. It is necessary to update and summarize research progress in miRNAs in renal fibrosis. Thus, in this review, we summarize progress in miRNA-mediated renal fibrosis over the last 5 years and evaluate the biological functions of some miRNAs in different stages of renal fibrosis. Furthermore, we also expound the recent clinical applications of these miRNAs to provide new insights into the treatment of renal fibrosis disease.

6.
J Environ Manage ; 254: 109810, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31698300

RESUMO

In order to predict the effects of climate change on the global carbon cycle, it is crucial to understand the environmental factors that affect soil carbon storage in grasslands. In the present study, we attempted to explain the relationships between the distribution of soil carbon storage with climate, soil types, soil properties and topographical factors across different types of grasslands with different grazing regimes. We measured soil organic carbon in 92 locations at different soil depth increments, from 0 to 100 cm in southwestern China. Among soil types, brown earth soils (Luvisols) had the highest carbon storage with 19.5 ±â€¯2.5 kg m-2, while chernozem soils had the lowest with 6.8 ±â€¯1.2 kg m-2. Mean annual temperature and precipitation, exerted a significant, but, contrasting effects on soil carbon storage. Soil carbon storage increased as mean annual temperature decreased and as mean annual precipitation increased. Across different grassland types, the mean carbon storage for the top 100 cm varied from 7.6 ±â€¯1.3 kg m-2 for temperate desert to 17.3 ±â€¯2.9 kg m-2 for alpine meadow. Grazing/cutting regimes significantly affected soil carbon storage with lowest value (7.9 ±â€¯1.5 kg m-2) recorded for cutting grass, while seasonal (11.4 ±â€¯1.3 kg m-2) and year-long (12.2 ±â€¯1.9 kg m-2) grazing increased carbon storage. The highest carbon storage was found in the completely ungrazed areas (16.7 ±â€¯2.9 kg m-2). Climatic factors, along with soil types and topographical factors, controlled soil carbon density along a soil depth in grasslands. Environmental factors alone explained about 60% of the total variation in soil carbon storage. The actual depth-wise distribution of soil carbon contents was significantly influenced by the grazing intensity and topographical factors. Overall, policy-makers should focus on reducing the grazing intensity and land conversion for the sustainable management of grasslands and C sequestration.


Assuntos
Carbono , Solo , Ciclo do Carbono , China , Pradaria , Poaceae
7.
Gigascience ; 8(12)2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31808800

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) are emerging as important regulators of various biological processes. While many studies have exploited public resources such as RNA sequencing (RNA-Seq) data in The Cancer Genome Atlas to study lncRNAs in cancer, it is crucial to choose the optimal method for accurate expression quantification. RESULTS: In this study, we compared the performance of pseudoalignment methods Kallisto and Salmon, alignment-based transcript quantification method RSEM, and alignment-based gene quantification methods HTSeq and featureCounts, in combination with read aligners STAR, Subread, and HISAT2, in lncRNA quantification, by applying them to both un-stranded and stranded RNA-Seq datasets. Full transcriptome annotation, including protein-coding and non-coding RNAs, greatly improves the specificity of lncRNA expression quantification. Pseudoalignment methods and RSEM outperform HTSeq and featureCounts for lncRNA quantification at both sample- and gene-level comparison, regardless of RNA-Seq protocol type, choice of aligners, and transcriptome annotation. Pseudoalignment methods and RSEM detect more lncRNAs and correlate highly with simulated ground truth. On the contrary, HTSeq and featureCounts often underestimate lncRNA expression. Antisense lncRNAs are poorly quantified by alignment-based gene quantification methods, which can be improved using stranded protocols and pseudoalignment methods. CONCLUSIONS: Considering the consistency with ground truth and computational resources, pseudoalignment methods Kallisto or Salmon in combination with full transcriptome annotation is our recommended strategy for RNA-Seq analysis for lncRNAs.

8.
BMC Genomics ; 20(1): 954, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818245

RESUMO

BACKGROUND: Predatory mites (Acari: Phytoseiidae) are the most important beneficial arthropods used in augmentative biological pest control of protected crops around the world. However, the genomes of mites are far less well understood than those of insects and the evolutionary relationships among mite and other chelicerate orders are contested, with the enigmatic origin of mites at one of the centres in discussion of the evolution of Arachnida. RESULTS: We here report the 173 Mb nuclear genome (from 51.75 Gb pairs of Illumina reads) of the predatory mite, Neoseiulus cucumeris, a biocontrol agent against pests such as mites and thrips worldwide. We identified nearly 20.6 Mb (~ 11.93% of this genome) of repetitive sequences and annotated 18,735 protein-coding genes (a typical gene 2888 bp in size); the total length of protein-coding genes was about 50.55 Mb (29.2% of this assembly). About 37% (6981) of the genes are unique to N. cucumeris based on comparison with other arachnid genomes. Our phylogenomic analysis supported the monophyly of Acari, therefore rejecting the biphyletic origin of mites advocated by other studies based on limited gene fragments or few taxa in recent years. Our transcriptomic analyses of different life stages of N. cucumeris provide new insights into genes involved in its development. Putative genes involved in vitellogenesis, regulation of oviposition, sex determination, development of legs, signal perception, detoxification and stress-resistance, and innate immune systems are identified. CONCLUSIONS: Our genomics and developmental transcriptomics analyses of N. cucumeris provide invaluable resources for further research on the development, reproduction, and fitness of this economically important mite in particular and Arachnida in general.

9.
Cancer Manag Res ; 11: 10029-10039, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819635

RESUMO

Purpose: We aim to construct a nomogram to predict breast cancer survival and guide postoperative adjuvant chemotherapy in China. Patients and methods: A total of 5,504 breast cancer patients from the Tianjin Breast Cancer Cases Cohort were included. Multivariable Cox regression was used to investigate the factors associated with overall survival (OS) and a nomogram was constructed based on these prognostic factors. The nomogram was internal and external validated and the performance was evaluated by area under the curve (AUC) and calibration curve. The partial score was also constructed and stratified them into low, moderate and high-risk subgroups for death according to the tripartite grouping method. Multivariate Cox regression analysis and the propensity score matching method were respectively used to test the association between adjuvant chemotherapy and OS in different risk subgroups. Results: Age, diameter, histological differentiation, lymph node metastasis, estrogen, and progesterone receptor were incorporated into the nomogram and validation results showed this nomogram was well-calibrated to predict the 3-year [AUC =74.1%; 95% confidence interval (CI): 70.1-78.0%] and 5-year overall survival [AUC =72.3%; 95% CI: 69.6-75.1%]. Adjuvant chemotherapy was negatively associated with death in high risk subgroup [Hazard Ratio (HR) = 0.54; 95% CI: 0.37-0.77; P<0.001]. However, no significant association were found in groups with low (HR=1.47; 95% CI: 0.52-4.19; P=0.47) and moderate risk (HR=0.78; 95% CI: 0.42-1.48; P=0.45). The 1:1 PSM generated 822 pairs of well-matched patients and Kaplan-Meier showed the high-risk patients could benefit from chemotherapy, whereas low risk and moderate risk subjects did not appear to benefit from chemotherapy. Conclusion: Not all of the breast cancer patients benefit equally from chemotherapy. The nomogram could be used to evaluate the overall survival of breast cancer patients and predict the magnitude of benefit and guide adjuvant chemotherapy for breast cancer patients after surgery.

11.
Thorac Cancer ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31788970

RESUMO

BACKGROUND: Non-small-cell lung cancer (NSCLC) is the most lethal type of cancer. Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been identified as crucial regulators in the development of NSCLC. The aim of our study was to explore the molecular mechanism of SNHG1 to enable better treatment for NSCLC patients. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of Small nucleolar RNA host gene 1 (SNHG1), miR-361-3p and frequently rearranged in advanced T-cell lymphomas 1 (FRAT1). The protein level of FRAT1 was measured by western blot assay. Cell proliferation was evaluated by methyl thiazolyl tetrazolium (MTT) assay. Cell apoptosis was assessed by flow cytometry assay. The number of migrated and invaded cells were counted by transwell assay. The relationship between miR-361-3p and SNHG1 or FRAT1 was confirmed by dual-luciferase reporter assay. RESULTS: Our results indicated that SNHG1 and FRAT1 were highly expressed in NSCLC tissues and cells. SNHG1 silencing inhibited proliferation, induced apoptosis and blocked migration and invasion of NSCLC cells. Also, FRAT1 downregulation suppressed proliferation, promoted apoptosis and hindered migration and invasion of NSCLC cells. Further, FRAT1 could recover the effects of SNHG1 silencing on proliferation, apoptosis, migration and invasion of NSCLC cells. SNHG1 sponged miR-361-3p and negatively regulated miR-361-3p expression. Meanwhile, miR-361-3p targeted FRAT1 and inversely modulated FRAT1 expression. In addition, miR-361-3p inhibition abated the effect of SNHG1 knockdown on FRAT1 expression. CONCLUSION: In conclusion, LncRNA SNHG1 promoted the proliferation, repressed apoptosis and enhanced migration and invasion of NSCLC cells by regulating FRAT1 expression via sponging miR-361-3p.

12.
Front Neurosci ; 13: 1217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803004

RESUMO

Introduction: Accumulated evidence indicates that obesity is associated with enhanced sympathetic activation. Hypothalamic leptin-mediated signaling may contribute to the exaggerated sympathoexcitation of obesity. The goal of this study was to investigate the "neuron-astrocyte" interaction affecting leptin-mediated sympathoexcitation within the arcuate nucleus (ARCN) of the hypothalamus in obese rats. Methods and Results: Obesity was induced by high-fat diet (HFD, 42% of calories from fat) in Sprague Dawley rats. Twelve weeks of HFD produced hyperleptinemia, hyperlipidemia, and insulin resistance. In anesthetized rats, microinjections of leptin into the ARCN induced increases in heart rate (HR), renal sympathetic nerve activity (RSNA), and mean arterial pressure (MAP) in both control and HFD rats. However, microinjections of leptin in HFD rats elicited higher responses of RSNA and arterial pressure than control-fed rats. It also caused the inhibition of astrocytes within the ARCN using an astrocytic metabolic inhibitor, fluorocitrate, and reduced leptin-induced sympathetic activity and blood pressure responses. Moreover, the expression of the leptin receptor in the ARCN of HFD-fed rats was significantly increased compared to rats fed a control diet. Immunohistochemistry analysis revealed leptin receptor localization from both neurons and astrocytes of the ARCN. HFD rats exhibited increased protein expression of glial fibrillary acidic protein (GFAP) in the ARCN. We also found that the expression of astrocyte-specific glutamate transporters and excitatory amino acid transporter 1 (EAAT1) and 2 (EAAT2) were decreased within the ARCN of the HFD rats. In cultured astrocytic C6 cells, 24 h of leptin treatment increased the protein expression of GFAP and reduced the expression of EAAT1 and EAAT2. Conclusion: The results suggest that central leptin signaling occurs via neuron-astrocyte interactions in the ARCN and contributing to the exaggerated sympathoexcitation observed in obese rats. The effects may be mediated by the action of leptin on regulating astrocytic glutamate transporters within the ARCN of the hypothalamus.

13.
Front Mol Biosci ; 6: 128, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803756

RESUMO

Mitochondria are the main producers of energy in eukaryotic cells. Mitochondrial dysfunction is associated with specific mitochondrial DNA (mtDNA) variations (haplogroups), and these variations can contribute to human disease. East Asian populations show enrichment of many mitochondrial haplogroups, including A, B, D, G, M7, M8, M9, N9, R9, and exhibit half of the known haplogroups of worldwide. In this review, we summarize the current research in the field of mtDNA variation and associated disease in East Asian populations and discuss the physiological and pathological relevance of mitochondrial biology. mtDNA haplogroups are associated with various metabolic disorders ascribed to altered oxidative phosphorylation. The same mitochondrial haplogroup can show either a negative or positive association with different diseases. Mitochondrial dynamics, mitophagy, and mitochondrial oxidative stress, ultimately influence susceptibility to various diseases. In addition, mitochondrial retrograde signaling pathways may have profound effects on nuclear-mitochondrial interactions, affecting cellular morphology, and function. Other complex networks including proteostasis, mitochondrial unfolded protein response and reactive oxygen species signaling may also play pivotal roles in metabolic performance.

14.
FEBS Lett ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31833055

RESUMO

Golgins are an abundant class of peripheral membrane proteins of the Golgi. These very long (50 - 400 nm) rod-like proteins initially capture cognate transport vesicles, thus enabling subsequent SNARE-mediated membrane fusion. Here, we explore the hypothesis that in addition to serving as vesicle tethers, Golgins may also possess the capacity to phase separate and, thereby, contribute to the internal organization of the Golgi. GM130 is the most abundant Golgin at the cis Golgi. Remarkably, overexpressed GM130 forms liquid droplets in cells analogous to those described for numerous intrinsically disordered proteins with low complexity sequences, even though GM130 is neither low in complexity nor intrinsically disordered. Virtually pure recombinant GM130 also phase-separates into dynamic, liquid-like droplets in close to physiological buffers and at concentrations similar to its estimated local concentration at the cis Golgi.

15.
J Biochem Mol Toxicol ; : e22430, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31833155

RESUMO

The aim of this study was to investigate the effect of melatonin (MT) and its metabolite N(1)-acetyl-N(2)-formyl-5-methoxykynuramine (AFMK) on Alzheimer-like learning and memory impairment in rats intracerebroventricularly injected with streptozotocin (STZ). The results showed that the escape latency of the STZ group was longer than that of the control (CON), MT, and AFMK groups. Increased levels of hyperphosphorylated tau, neurofilament proteins, and malondialdehyde and decreased superoxide dismutase levels were observed in the brains of the rats from the STZ group compared with the brains of the rats from the CON, MT, AFMK high and low group. These results suggest that exogenous MT and AFMK can improve memory impairment and downregulate AD-like hyperphosphorylation induced by STZ, most likely through their antioxidation function. Meanwhile, we found that an equal dose of AFMK had a stronger effect than that of MT. Our results indicate that MT and its metabolite AFMK represent novel treatment strategies for Alzheimer's disease.

16.
JBJS Case Connect ; 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31833976

RESUMO

CASE: Non-neoplastic bone destruction, known as Andersson lesion, is not rare in ankylosing spondylitis (AS) and always appeared as bone destruction and sclerosis in the vertebral body-intervertebral disc region. The Andersson lesion has been reported mostly in the thoracic and lumbar spine and rarely in the lower cervical spine. We surgically treated a patient with AS complicated with atlantoaxial dislocation and destruction of dens and lateral atlantoaxial joint, which was similar to the Andersson lesion. CONCLUSIONS: AS can cause destructive lesion in the upper cervical spine. Posterior reduction, removal of the lesion, and fusion were possible approaches for the treatment of this destructive lesion.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31838561

RESUMO

Oral VRL offers easier administration, better quality of life, and cost saving. This study aimed to evaluate the treatment efficacy in terms of tumor response of the two formulations of vinorelbine (VRL, oral and IV) in combination with epirubicin (EPI); and the effect of EPI co-administration on VRL pharmacokinetics (PK) in Chinese patients with metastatic breast cancer (MBC) using a phase 2, open label, randomized trial. Patients were aged 18-70 years, had histologically confirmed MBC, Karnofsky Performance Status ≥ 70%, and life expectancy ≥ 12 weeks. The treatment consisted of 6 cycles of 3 weeks each. VRL dose was: (Oral-VRL) 60 mg/m2 for cycle 1, 80 mg/m2 for cycles 2-6, and (IV-VRL) 25 mg/m2 for cycle 1 and 30 mg/m2 for cycles 2-6. EPI dose of 75 mg/m2 was given on day 1 in both arms for all cycles. 133 patients were enrolled: 66 in Oral-VRL and 67 in IV-VRL arms. The median age for Oral-VRL and IV-VRL arms was 48.4 and 50.0 years, respectively. Objective response rates were 50.0% (95% CI 37.4-62.6%) for Oral-VRL and 53.7% (95% CI 41.1-66.0%) for IV-VRL. Both treatment arms met the efficacy objective target of at least 31 responses, demonstrating efficacy as first-line treatment for MBC. Similar blood PK profiles, exposures, and VRL clearance were observed between VRL + EPI vs VRL-only modalities for both arms. Oral VRL is comparable to IV VRL and an effective first-line treatment for Chinese patients with MBC. The activity of VRL + EPI combination is unaltered when VRL is given orally at recommended doses.

18.
J Cell Mol Med ; 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31851778

RESUMO

OBJECTIVE: In this study, we explored the NPC-specific expression of ZFAS1 and the mechanism of ZFAS1-mediated growth, aggressiveness and tumorigenesis in NPC. METHODS: The expression profile of lncRNAs was detected in NPC tissues and matching para-carcinoma tissues using microarray analysis. LncRNA-miRNA and miRNA-mRNA interaction networks were constructed using the miRcode v11 and TargetScanHuman v7.2 web server and then validated using dual-luciferase assay. Western blot and RT-qPCR were performed to detect protein and RNA expression. The effects of ZFAS1, miR-892b and LPAR1 dysregulation on the proliferative, migratory and invasive abilities of NPC cells were observed using colony formation, cell counting kit-8 (CCK-8) and transwell assays in vitro. In vivo, a xenograft nude mouse model was established to detect the impact of ZFAS1 dysregulation on the tumorigenicity of NPC cells. RESULTS: The expression of multiple lncRNAs, of which ZFAS1 was up-regulated, was dysregulated in NPC tissues. ZFAS1 directly targeted miR-892b, and miR-892b negatively regulated the expression of downstream LPAR1. The proliferation, migration and invasion of NPC cells could be largely enhanced by the downregulation of miR-892b as well as the up-regulation of ZFAS1 and LPAR1, while the overexpression of miR-892b and the downregulation of ZFAS1 and LPAR1 decreased these abilities. In nude mice, the growth of tumour xenografts formed by HONE1 cells was significantly suppressed when ZFAS1 was silenced. CONCLUSION: The study demonstrated that lncRNA ZFAS1 may act as a promoter of tumorigenesis and metastasis in nasopharyngeal carcinoma, by up-regulating the expression of LPAR1 in a miR-892b-dependent manner.

19.
J Hazard Mater ; : 121746, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31859166

RESUMO

Single atom catalysts with atomically distributed active metal centers have attracted great attention owing to their maximum atom efficiency and excellent activity. Herein, we report a novel photocatalyst with isolated Pt single atomic sites anchored on nanoporous TiO2 film prepared by a facile immersion and reduction method. HAADF-STEM, XPS, XANES and EXAFS results confirmed the anchoring of Pt single atomic sites on nanoporous TiO2 film. The effects of immersion concentration of Pt, reduction temperature, relative humidity, inlet toluene concentration and residence time on photocatalytic degradation of low concentration toluene under UV and VUV irradiation were investigated. The results showed that the as-prepared catalyst had considerably high photocatalytic activity. The removal rate of toluene reached 45.88% under VUV irradiation when the inlet toluene concentration and residence time were 200 ppb and 0.3 s, respectively, which was 5.94 times that of pristine nanoporous TiO2 film. The by-product ozone removal was greatly improved and the corresponding energy consumption was 0.01 kW·h/m3. While the removal rate of toluene increased with the decrease of inlet toluene concentration under UV irradiation. The Pt single atom catalyst exhibits significant potential for photocatalytic degradation of low concentration VOCs in indoor environments.

20.
Int J Biol Macromol ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31751710

RESUMO

Osteoporosis is the most widespread metabolic bone disease characterized by decreased bone mass and bone quality, and its diagnosis and treatment remains challenging. To date, medicinal plants have received increasing attention from researchers for researching effective and less toxic therapeutic ingredients, including polysaccharide, to treat osteoporosis. The present study aims to evaluate the osteoprotective effects of a polysaccharide (EBP) from Epimedium brevicornum in glucocorticoid-induced osteoporosis in vitro and investigate the underlying mechanism. EBP (25 and 100 µg/ml) pretreatment could significantly prevent decreased cell proliferation of osteoblasts (OBs) treated only with 100 µM of dexamethasone (Dex) via induction of apoptosis. The osteoblastic differentiation of EBP pretreatment on OBs at early and later phase was further confirmed by the increased alkaline phosphatase (ALP) activity and calcium content, respectively. Meanwhile, the increased expression of cleaved caspase-3 and Bax, as well as a decrease of Bcl-2 and the phosphorylation of PI3K, Akt and mTOR protein in Dex-treated OBs were totally reversed by EBP pretreatment. Moreover, the protein expression of Lrp-5, ß-catenin, Runx2 and Osx were significantly up-regulated in the presence of EBP pretreatment. In conclusion, these results demonstrated that EBP pretreatment may be a potential therapeutic agent for patients with glucocorticoid-induced osteoporosis (GIO).

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