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1.
Mol Genet Genomic Med ; : e1267, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32478482

RESUMO

Sarcopenia is a complex polygenic disease, and its molecular mechanism is still unclear. Whole lean body mass (WLBM) is a heritable trait predicting sarcopenia. To identify genomic loci underlying, we performed a whole-exome sequencing (WES) of WLBM variation with high sequencing depth (more than 40*) in 101 Chinese subjects. We then replicated in the major findings in the large-scale UK Biobank (UKB) cohort (N = 217,822) for WLBM. The results of four single-nucleotide polymorphisms (SNPs) were significant both in the discovery stage and replication stage: SNP rs740681 (discovery p = 1.66 × 10-6 , replication p = .05), rs2272303 (discovery p = 3.20 × 10-4 , replication p = 3.10 × 10-4 ), rs11170413 (discovery p = 3.99 × 10-4 , replication p = 2.90 × 10-4 ), and rs2272302 (discovery p = 9.13 × 10-4 , replication p = 3.10 × 10-4 ). We combined p values of the significant SNPs. Functional annotations highlighted two candidate genes, including FZR1 and SOAT2, that may exert pleiotropic effects to the development of body mass. Our findings provide useful insights that further enhance our understanding of genetic interplay in sarcopenia.

2.
Theranostics ; 10(12): 5600-5612, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32373234

RESUMO

Chronic infection by hepatitis B virus (HBV) is associated with high risks of liver fibrosis, cirrhosis and hepatocellular carcinoma. In mouse models of HBV persistence, interleukin 21 (IL-21) has been identified as a potent inducer of viral clearance. Strict hepatotropism makes recombinant HBV (rHBV) vectors ideal for liver-targeting gene delivery. Previously, we established an rHBV vector termed 5c3c, which is highly replicative by itself, but requires HBV envelope proteins provided in trans to produce virions. 5c3c-based rHBV virions are capable of delivering cargo gene expression driven by HBV Sp1 promoter into infected hepatocytes. In this work, we explore the feasibility of using 5c3c-derived rHBV for liver-specific delivery of IL-21 as treatment of chronic HBV infection. Methods: 5c3c-derived rHBV replicons harboring mouse or human IL-21 genes (termed 5c3c-mIL-21 and 5c3c-hIL-21 respectively) were constructed and then tested for the production of rHBV virions in vitro and in vivo. 5c3c-mIL-21's anti-HBV effects were determined in chronic HBV mouse model. Furthermore, superinfection by rHBV virions was analysed using HBV-infected HepG2/NTCP cells and human liver chimeric mice. Results: 5c3c-mIL-21 and 5c3c-hIL-21 were efficiently replicative and produced enveloped virions when provided with envelope proteins, both in vitro and in vivo. In mouse model of HBV persistence, IL-21 expressed from injected 5c3c-mIL-21 replicon induced complete viral clearance. 5c3c-mIL-21 and 5c3c-hIL-21 virions could infect HepG2/NTCP cells and engender sustained IL-21 expression. Most importantly, IL-21-expressing rHBV virions could superinfect HBV-infected HepG2/NTCP cells and human hepatocytes in human liver chimeric mice, and engender sustained IL-21 expression and rHBV production. Conclusion: These data suggest the high potential of 5c3c-derived IL-21-expressing rHBV as a novel therapeutic against chronic HBV infection.

3.
Metabolites ; 10(5)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414018

RESUMO

The activation of the Ras signaling pathway is a crucial process in hepatocarcinogenesis. Till now, no reports have scrutinized the role of dynamic metabolic changes in Ras oncogene-induced transition of the normal and precancerous liver cells to hepatocellular carcinoma in vivo. In the current study, we attempted a comprehensive investigation of Hras12V transgenic mice (Ras-Tg) by concatenating nontargeted metabolomics, transcriptomics analysis, and targeted-metabolomics incorporating [U-13C] glucose. A total of 631 peaks were detected, out of which 555 metabolites were screened. Besides, a total of 122 differently expressed metabolites (DEMs) were identified, and they were categorized and subtyped with the help of variation tendency analysis of the normal (W), precancerous (P), and hepatocellular carcinoma (T) liver tissues. Thus, the positive or negative association between metabolites and the hepatocellular carcinoma and Ras oncogene were identified. The bioinformatics analysis elucidated the hepatocarcinogenesis-associated significant metabolic pathways: glycolysis, mitochondrial citrate-malate shuttle, lipid biosynthesis, pentose phosphate pathway (PPP), cholesterol and bile acid biosynthesis, and glutathione metabolism. The key metabolites and enzymes identified in this analysis were further validated. Moreover, we confirmed the PPP, glycolysis, and conversion of pyruvate to cytosol acetyl-CoA by mitochondrial citrate-malate shuttle, in vivo, by incorporating [U-13C] glucose. In summary, the current study presented the comprehensive bioinformatics analysis, depicting the Ras oncogene-induced dynamic metabolite variations in hepatocarcinogenesis. A significant finding of our study was that the mitochondrial citrate-malate shuttle plays a crucial role in detoxification of lactic acid, maintenance of mitochondrial integrity, and enhancement of lipid biosynthesis, which, in turn, promotes hepatocarcinogenesis.

4.
Pharm Biol ; 58(1): 454-464, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32432951

RESUMO

Context: ShengMaBieJia decoction (SMBJD) is used to treat solid and hematological tumours; however, its anti-angiogenesis activity remains unclear.Objective: This study verified the anti-angiogenic effects of SMBJD in vitro and in tumour-bearing acute myeloid leukaemia (AML) mouse models.Materials and methods: In vivo, the chicken chorioallantoic membrane (CAM) and BALB/c null mouse xenograft models were treated with SMBJD (0, 2, 4, and 8 mg/mL) for 48 h and for 2 weeks, respectively. Anti-angiogenic activity was assessed according to microvessel density (MVD) and immunohistochemistry (IHC) targeting CD31 and VEGFR2. In vitro, proliferation viability, migratory activity and tube formation were measured. Western blots and polymerase chain reaction (PCR) assays were used to examine the levels of PI3K, Akt, and VEGF.Results: HPLC analyses revealed the active constituents of SMBJD such as liquiritin, cimifugin, ferulic, isoferulic, and glycyrrhizic acids. In vitro, SMBJD treatment decreased cellular migration, chemotaxis, and tube formation at non-cytotoxic concentrations (2, 4, and 8 mg/mL) in a time- and dose-dependent manner. The dosage of less than IC20 is considered safe. In vivo, CAM models exhibited a decrease in MVD, and the tissues of xenografted mice possessed reduced CD31 and VEGFR2 expression. Conditioned media (CM) from AML cells (HL60 and NB4 cells) treated with non-cytotoxic doses of SMBJD inhibited chemotactic migration and tube formation in vitro. Both CM (HL60) and CM (NB4) exhibited downregulated expression of PI3K, Akt, and VEGF.Discussion and conclusions: SMBJD inhibited angiogenesis in AML through the PI3K/AKT pathway, which might be combined with targeted therapy to provide more effective treatment.

5.
Cell Death Dis ; 11(5): 404, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472021

RESUMO

Dysfunction of intestinal epithelial Cl- currents and channels have previously been reported in inflammatory intestinal diseases. However, the expression and function of the newly identified Ca2+-activated Cl- channel transmembrane member 16A (TMEM16A) in the intestinal epithelium is unclear. In this study, we investigated the effects of TMEM16A on intestinal epithelial barrier function in vitro. Intestinal epithelial barrier dysfunction was modeled by lipopolysaccharide (LPS)-induced cell damage in intestinal epithelial IEC-6 cells and the effects of TMEM16A knockdown and overexpression on cell apoptosis and tight junctions were studied. Corresponding mRNA and protein expression levels were measured by quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence analysis, respectively. TMEM16A expression was significantly increased by LPS, possibly via a process involving the transcription factor nuclear factor-κB and both Th1 and Th2 cytokines. Low- and high-dose LPS dysregulated tight junctions (high-myosin light-chain kinase expression) and cell apoptosis-dependent cell barrier dysfunction, respectively. TMEM16A aggravated cell barrier dysfunction in IEC-6 cells pretreated with low-dose LPS by activating ERK1/MLCK signaling pathways, but protected against cell barrier dysfunction by activating ERK/Bcl-2/Bax signaling pathways in IEC-6 cells pretreated with high-dose LPS. We concluded that TMEM16A played a dual role in LPS-induced epithelial dysfunction in vitro. The present results indicated the complex regulatory mechanisms and targeting of TMEM16A may provide potential treatment strategies for intestinal epithelial barrier damage, as well as forming the basis for future studies of the expression and function of TMEM16A in normal and inflammatory intestinal diseases in vivo.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32427459

RESUMO

Cellulosic materials are attractive candidates for nature piezoelectrics. Vertically aligned cellulose nanocrystal (CNC) films are expected to show strong piezoelectricity as the largest dipole moment in CNCs exists along the cellulose chain. In this work, we adapted the confinement cell technology that was used to fabricate colloidal opal structures to align CNC rods vertically on a large scale. The high interfacial energy between the CNC-poly(tetrafluoroethylene) (PTFE) surface and torque induced by the shear force led to a large degree to the vertical alignment of CNC rods. An external DC electric field was added to further align the dipole moment of each CNC to the same direction. The as-obtained CNC film displayed excellent piezoelectric performance, and the piezoelectric coefficient was found to be 19.3 ± 2.9 pm/V, comparable to the piezoelectric coefficient d33 of poly(vinylidene difluoride) (PVDF) (20-30 pm/V). This work presents a new class of high-performance piezoelectric polymeric materials from renewable and biocompatible natural resources.

7.
Biomed Res Int ; 2020: 8379358, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32462021

RESUMO

Materials and Methods: The petroleum ether (petrol), dichloromethane (CH2Cl2), ethyl acetate (EtOAc), and n-butyl alcohol (n-BuOH) fractions were isolated from alcohol extracts of D. moldavica L. Total phenolic and flavonoid contents and in vitro antioxidant activities of different fractions were evaluated. H9c2 cells were then treated with D. moldavica L. extracts before challenging with H2O2. Cell viability was determined by colorimetric assay, and ELISA was used to measure the levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), and superoxide dismutase (SOD). Apoptosis levels and mitochondrial membrane potential were measured by flow cytometry. The expressions of cell apoptosis regulatory proteins caspase-3, Bax, and Bcl-2 were determined by western blotting. Results: Our results demonstrated that the EtOAc fraction from D. moldavica L. ethanol extract, which is rich in phenolic and flavonoid active constituents, had the strongest free radical scavenging activity. Additionally, this fraction increased H2O2-induced reduction in cell viability, SOD activity, and mitochondrial membrane potential. It also reduced H2O2-induced elevation in ROS production, contents of LDH and MDA, and H9c2 apoptosis. We further found that the EtOAc fraction increased Bcl-2 expression, while it decreased caspase-3 and Bax expressions induced by H2O2 in H9c2 cells. Conclusions: Our data revealed that the EtOAc fraction from D. moldavica L. ethanol extract ameliorates H2O2-induced cardiotoxicity via antiapoptotic and antioxidant mechanisms.

8.
Biomed Chromatogr ; : e4870, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32346871

RESUMO

In this study, a simple and reliable liquid chromatography tandem mass spectrometry method was first proposed for simultaneous determination of TUG-891 and its metabolites TUG-891-alcohol, TUG-891-aldehyde and TUG-891-acid in rat plasma. The analytes and fasiglifam (internal standard) were extracted from plasma samples with acetonitrile and separated on ACQUITY BEH C18 column (1.7 µm, 2.1 × 50 mm) with water containing 0.05% ammonium hydroxide and acetonitrile containing 0.05% ammonium hydroxide as mobile phase. Q-Exactive Orbitrap mass spectrometer in full scan mode was employed for mass detection and the data analysis was obtained using a mass extraction window of 5 ppm. The calibration curves exhibited excellent linearity (correlation coefficient >0.9981) in the concentration range of 0.5-1000 ng/mL. The lower limit of quantification was 0.5 ng/mL for all analytes. The intra- and inter-day precision was less than 11.31% and the accuracy ranged from -11.50 to 9.50%. The extraction recovery of the analytes from rat plasma was >82.31% and no obvious matrix effect was found. The established method was further applied to the pharmacokinetic study of TUG-891, TUG-891-alcohol, TUG-891-aldehyde and TUG-891-acid in rat after a single dose of 5 mg/kg treatment of TUG-891. The results demonstrated that TUG-891 was rapidly metabolized into its metabolites and the systemic exposures of the metabolites were much higher than that of TUG-891.

9.
Anal Chem ; 92(10): 7146-7153, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32297736

RESUMO

Metallic nanoclusters (NCs) have molecular-like structures and unique physical and chemical properties, making them an interesting new class of luminescent nanomaterials with various applications in chemical sensing, bioimaging, optoelectronics, light-emitting diodes (LEDs), etc. However, weak photoluminescence (PL) limits the practical applications of NCs. Herein, an effective and facile strategy of enhancing the PL of NCs was developed using Ag shell-isolated nanoparticle (Ag SHIN)-enhanced luminescence platforms with tuned SHINs shell thicknesses. 3D-FDTD theoretical calculations along with femtosecond transient absorption and fluorescence decay measurements were performed to elucidate the enhancement mechanisms. Maximum enhancements of up to 231-fold for the [Au7Ag8(C≡CtBu)12]+ cluster and 126-fold for DNA-templated Ag NCs (DNA-Ag NCs) were achieved. We evidenced a novel and versatile method of achieving large PL enhancements with NCs with potential for practical biosensing applications for identifying target DNA in ultrasensitive surface analysis.

10.
FASEB J ; 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32314833

RESUMO

Uropathogenic Escherichia coli (UPEC), a leading cause of urinary tract infections, is associated with prostate and bladder cancers. Cytotoxic necrotizing factor 1 (CNF1) is a key UPEC toxin; however, its role in bladder cancer is unknown. In the present study, we found CNF1 induced bladder cancer cells to secrete vascular endothelial growth factor (VEGF) through activating Ras homolog family member C (RhoC), leading to subsequent angiogenesis in the bladder cancer microenvironment. We then investigated that CNF1-mediated RhoC activation modulated the stabilization of hypoxia-inducible factor 1α (HIF1α) to upregulate the VEGF. We demonstrated in vitro that active RhoC increased heat shock factor 1 (HSF1) phosphorylation, which induced the heat shock protein 90α (HSP90α) expression, leading to stabilization of HIF1α. Active RhoC elevated HSP90α, HIF1α, VEGF expression, and angiogenesis in the human bladder cancer xenografts. In addition, HSP90α, HIF1α, and VEGF expression were also found positively correlated with the human bladder cancer development. These results provide a potential mechanism through which UPEC contributes to bladder cancer progression, and may provide potential therapeutic targets for bladder cancer.

11.
Drug Discov Today ; 2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32320854

RESUMO

Disulfiram (DSF) is a thiuram derivative that was developed to treat alcoholism but was also found to have antitumor activity. Copper (Cu), as a trace metal, has important roles in the body. Numerous studies have shown that the combination of DSF and copper (DSF/Cu) greatly enhances its antitumor efficacy. Given that the efficacy of DSF is well established and its safety profile is understood, repurposing DSF as a new anticancer drug is a promising strategy. Here, we summarize the pharmacological effects of DSF and the role of Cu in cancer, and focus on the antitumor effect of DSF/Cu, especially the mechanisms involved in enhancing drug sensibility by targeting specific molecules. We also provide rational strategies for using DSF as a cancer therapy.

12.
Biotechnol Lett ; 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32140881

RESUMO

OBJECTIVE: In this study, we observed the effects of IL-33 on tumor immune response in lung cancer-bearing mice using wild type and MyD88-/- mice respectively. METHODS: Wild C57BL/6 (C57BL/6WT), MyD88 knockout C57BL/6 mice (C57BL/6 MyD88-/-) and Lewis cells were used in this study. Cell proliferation, cytokine release and cytotoxicity were detected. RESULTS: IL-33 could significantly up-regulate specific cellular immunity, inhibit tumor growth and improve survival time in wild type mice group, and it had dose dependent effect. However, IL-33 had no effect on cell immunity and tumor growth in MyD88-/- mice group. Compared with MyD88-/- mice, IL-33 could significantly increase the ratio of CD8+T cells to neutrophils in wild type mice, while the percentage of tumor infiltrating CD11b+ cells, Mo-MDSC, F4/80+ macrophages and mDC cells decreased significantly in wild type mice group. IL-33 could upregulate the expression of CD107a and IFN-γ in CD8+T cells and NK cells of wild type mice, while IL-33 could not upregulate them in MyD88-/- mice. IL-33 could upregulate the expression of CD40, CD80, CD86 and CD205 in DC cells in wild type mice, induce T cells to differentiate into Th1 cells and enhance tumor cell immunity. CONCLUSIONS: IL-33 could promote differentiation and maturation of DC cells through MyD88 pathway, up-regulate the tumor immunity of CD8+T cells and NK cells, and inhibit the proliferation of lung cancer cells.

13.
J Food Biochem ; 44(5): e13173, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32150658

RESUMO

Production of a thermostable pullulanase by DO-stat fed-batch fermentation of recombinant Escherichia coli BL 21 was investigated in a 5 L of fermentor. The effect of three oxygen control strategies, glucose feedback, shifting fermentor pressure, and adding oxygen-enriched air, on cell growth and pullulanase expression were examined. The oxygen-transfer capacity was found to be enhanced with increasing fermentor pressure and oxygen ratio in oxygen-enriched air, but the cell growth and pullulanase production were restrained under high fermentor pressure. The highest cell density and pullulanase activity reached 55.1 g/L and 412 U/mL, respectively, in the case by adding oxygen-enriched air, which was suggested as an effective approach to enhance both cell growth and pullulanase production. PRACTICAL APPLICATIONS: This thermostable pullulanase displayed optimal activity at 90°C and pH 5.4, which could be applied for one-step saccharification of starch biomass. The optimization of the DO-stat fed-batch fermentation in high cell density level would provide a research basis for its industrialization.

14.
Diabetes Care ; 43(4): 925-933, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32198286

RESUMO

BACKGROUND: Identifying patients at high risk of diabetic kidney disease (DKD) helps improve clinical outcome. PURPOSE: To establish a model for predicting DKD. DATA SOURCES: The derivation cohort was from a meta-analysis. The validation cohort was from a Chinese cohort. STUDY SELECTION: Cohort studies that reported risk factors of DKD with their corresponding risk ratios (RRs) in patients with type 2 diabetes were selected. All patients had estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 and urinary albumin-to-creatinine ratio (UACR) <30 mg/g at baseline. DATA EXTRACTION: Risk factors and their corresponding RRs were extracted. Only risk factors with statistical significance were included in our DKD risk prediction model. DATA SYNTHESIS: Twenty cohorts including 41,271 patients with type 2 diabetes were included in our meta-analysis. Age, BMI, smoking, diabetic retinopathy, hemoglobin A1c, systolic blood pressure, HDL cholesterol, triglycerides, UACR, and eGFR were statistically significant. All these risk factors were included in the model except eGFR because of the significant heterogeneity among studies. All risk factors were scored according to their weightings, and the highest score was 37.0. The model was validated in an external cohort with a median follow-up of 2.9 years. A cutoff value of 16 was selected with a sensitivity of 0.847 and a specificity of 0.677. LIMITATIONS: There was huge heterogeneity among studies involving eGFR. More evidence is needed to power it as a risk factor of DKD. CONCLUSIONS: The DKD risk prediction model consisting of nine risk factors established in this study is a simple tool for detecting patients at high risk of DKD.

15.
Sci Rep ; 10(1): 5057, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193455

RESUMO

Sarcopenia is characterized by low skeletal muscle, a complex trait with high heritability. With the dramatically increasing prevalence of obesity, obesity and sarcopenia occur simultaneously, a condition known as sarcopenic obesity. Fat mass and obesity-associated (FTO) gene is a candidate gene of obesity. To identify associations between lean mass and FTO gene, we performed a genome-wide association study (GWAS) of lean mass index (LMI) in 2207 unrelated Caucasian subjects and replicated major findings in two replication samples including 6,004 unrelated Caucasian and 38,292 unrelated Caucasian. We found 29 single nucleotide polymorphisms (SNPs) in FTO significantly associated with sarcopenia (combined p-values ranging from 5.92 × 10-12 to 1.69 × 10-9). Potential biological functions of SNPs were analyzed by HaploReg v4.1, RegulomeDB, GTEx, IMPC and STRING. Our results provide suggestive evidence that FTO gene is associated with lean mass.

16.
Molecules ; 25(6)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32188020

RESUMO

Both rosiglitazone and metformin have effects on blood glucose regulation and the proliferation of liver cancer cells. Combination therapy with these two drugs is common and effective for the treatment of diabetes in the clinic, however, the application of these two drugs is influenced by the poor dissolution of rosiglitazone and the gastrointestinal side-effect of metformin resulting from a high solubility. The formation of a multidrug crystal form (Rsg-Met) by a solvent evaporation method can solve the solubility issue. Crystal structure data and intramolecular hydrogen bonds were detected by X-ray diffraction and infrared spectroscopy. Surprisingly, Rsg-Met shortens the time spent in solubility equilibrium and multiplies the dissolution rate of Rsg. Finally, we found that a low concentration of Rsg-Met enhanced the proliferation inhibition effect on liver cancer cells (HepG2, SK-hep1) compared with rosiglitazone, without affecting the human normal cell line LO2.

17.
Chemosphere ; 252: 126488, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32199167

RESUMO

Rare earth elements (REEs) are widely used in electronic products. But the contaminations of REEs in the e-waste sites and the related health effects were barely investigated. In the present study, we analyzed the concentrations of REEs and the hormones of the HPT axis in plasma of subjects recruited from an e-waste area and a reference area in Taizhou, China. The results showed that the concentrations of several REEs like La, Ce were much higher in the exposed group than in the control group (all p < 0.001). The thyroid hormones, FT3 and FT4, and TRH showed no significant difference between the two groups, while the concentration of TSH was significantly higher in the exposed group when compared to the control group (p = 0.002). Separate regression analysis indicated that elevated La and Ce levels were associated with higher TSH concentrations. MDA and 8-iso, the biomarkers of oxidative stress, were also significantly higher in the exposed group than that of the control group (p = 0.002 and p = 0.003, respectively). The increased oxidative stress might be the mechanism underlying the disruptive effects of REEs on TSH. Our results indicated that the quantities of internal exposure of REEs in the subjects in the e-waste area were considerable and the compositional profile of the REEs in the exposed group was different from the control group due to the e-waste dismantling. The expression of TSH were also affected by high La and Ce exposure which showed an endocrine disruption effects of REEs on HPT axis.

18.
IEEE Trans Cybern ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32011277

RESUMO

Discriminative correlation filters (DCF)-based trackers have been increasingly applied to visual tracking due to their high precision while running at high frame rates. However, most recent DCF-based methods solely concentrate on learning the correlation filter with spatial information and thus do not have sufficient descriptive power to discriminate the target from the background in the complex circumstances, such as full occlusion (OCC) and rapid target variation. In this article, we introduce a novel tracking framework that exploits the relationship between the target and its spatiotemporal context to improve tracking accuracy and robustness. Especially, we present our spatiotemporal context model in a hierarchical way, where each layer of the context pyramid is a spatial correlation filter learned from different temporal instances. For gaining an accurate spatiotemporal model, we propose an optimization fusion approach that can adaptively and efficiently learn the effect of each hierarchical layer and exploit these multiple temporal levels of correlation filters for visual tracking. Moreover, an adaptive model update strategy for correlation filters is introduced into the framework to dynamically select proper hierarchical layers, which boosts the temporal diversity of the target appearance, while radically reduces the number of model parameters and guarantees the real-time performance of the tracking method. The experimental results show that, with conventional handcrafted features, our tracker achieves the best success rates among available state-of-the-art trackers with handcrafted features, and provides state-of-the-art performance comparable to those of deep-learning-based trackers on OTB-2013, OTB-2015, VOT-2016, and UAV-20L benchmarks but runs significantly faster than deep trackers.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32098119

RESUMO

The current study aims to investigate the influence of five rare earth elements (REEs) (i.e., lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), and gadolinium (Gd)) on the growth of Sprague-Dawley (SD) rats, and to explore the accumulation characteristics of REEs in tissues and organs with different doses as well as the detoxification and elimination of high-dose REEs. Fifty healthy male SD rats (140~160 g) were randomly divided into five groups and four of them were given gavage of sodium citrate solution with REEs in different doses, one of which was the control group. Hair, blood, and bone samples along with specific viscera tissue samples from the spleen and the liver were collected for detection of REEs by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Treated rats expressed higher concentrations of REEs in the bones, the liver, and spleen samples than the control group (P < 0.05). Few differences were found in relative abundance of La, Ce, Pr, Nd, and Gd in the hair and the liver samples, although different administration doses were given. The relative abundance of Ce in bone samples was significantly lower in the low-dose group and control group, whereas the relative abundance of La and Pr in the bone samples were highest among all groups. Although in the REEs solution, which was given to rats in high-dose group, the La element had a higher relative abundance than Ce element, it ended up with higher Ce element relative abundance than La element in the spleen samples. REEs had a hormetic effect on body weight gain of SD rats. The accumulation of the measured REEs were reversible to low concentrations in the blood and hair, but non-reversible in the bones, the spleen, and the liver. Different tissues and organs can selectively absorb and accumulate REEs. Further inter-disciplinary studies about REEs are urgently needed to identify their toxic effects on both ecosystems and organisms.

20.
Environ Sci Process Impacts ; 22(2): 418-429, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32002526

RESUMO

The emergence of vancomycin-resistant Enterococcus faecalis (E. faecalis) in water is threatening the health of human beings. The effect of ultraviolet disinfection on vancomycin-resistant E. faecalis, including the effectiveness, photoreactivation and dark repair of E. faecalis, and the deactivation mechanism were investigated in this work. Ultraviolet disinfection could quickly inactivate the target antibiotic resistant bacterium (ARB), E. faecalis, and it caused damage to the cell membrane and induced the decrease of the total adenosine triphosphate (ATP) content and the superoxide dismutase (SOD) activity significantly (p < 0.05). E. faecalis could reactivate after ultraviolet disinfection especially under light conditions. Furthermore, the removal of the selected antibiotic resistance gene (ARG), vanB, by ultraviolet radiation and the effect on the vancomycin resistance of E. faecalis were investigated, which showed that ultraviolet disinfection had no significant effect on the vancomycin resistance of E. faecalis (p > 0.05).


Assuntos
Antibacterianos , Resistência Microbiana a Medicamentos , Enterococcus faecalis , Raios Ultravioleta , Vancomicina , Desinfecção , Enterococcus faecalis/efeitos dos fármacos , Humanos
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