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1.
Mater Sci Eng C Mater Biol Appl ; 108: 110214, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923933

RESUMO

In this work, PdNPs@ZnO-Co3O4 was synthesized via the facile oxidation treatment of bimetallic ZnCo-zeolitic-imidazolate-framework (ZnCo-ZIF) followed by in situ chemical reduction of PdNPs on the surface of the nanocrystals. After combined with MWCNTs, the PdNPs@ZnO-Co3O4-MWCNTs nanocomposites were formed, which were then exploited as novel electrode materials to construct the non-enzyme electrochemical sensors for high-sensitivity detection of tanshinol. Due to the high catalytic activity of multi-metallic PdNPs@ZnO-Co3O4, and the excellent charge transfer property between imidazole groups of the ligands in MOFs and MWCNTs, the obtained sensor exhibited high sensitivity for tanshinol detection under optimum experimental conditions. The sensor shows two well linear relationship between the current and tanshinol concentration in the range of 0.002-0.69 mM (R2 = 0.989) and 0.69-3.75 mM (R2 = 0.994) with the corresponding sensitivity of 59.16 µA mM-1 and 19.08 µA mM-1. And the limit of detection (LOD) was calculated to be 0.019 µM (S/N = 3). Furthermore, with the advantages of good repeatability, stability and selectivity, the fabricated sensor can be successfully applied to measurement of tanshinol in real medicinal liquids samples. Our results would accelerate the applications of MOFs in electrochemical field and provide insights into design of multifunctional non-enzyme sensing materials for various applications in biocatalysis, bioanalysis and drug testing.

2.
Brain Res Bull ; 154: 51-60, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31715311

RESUMO

The central nervous system (CNS) has a poor self-repairing capability after injury because of the inhibition of axonal regeneration by many myelin-associated inhibitory factors. Therefore, ischemic stroke usually leads to disability. Previous studies reported that Ginsenoside Rb1 (GRb1) plays a role in neuronal protection in acute phase after ischemic stroke, but its efficacy in post-stroke and the underlying mechanism are not clear. Recent evidences demonstrated GRb1 promotes neurotransmitter release through the cAMP-depend protein kinase A (PKA) pathway, which is related to axonal regeneration. The present study aimed to determine whether GRb1 improves long-term motor functional recovery and promotes cortical axon regeneration in post-stroke. Adult male C57BL/6 mice were subjected to distal middle cerebral artery occlusion (dMCAO). GRb1 solution (5 mg/ml) or equal volume of normal saline was injected intraperitoneally for the first time at 24 h after surgery, and then daily injected until day 14. Day 3, 7, 14 and 28 after dMCAO were used as observation time points. Motor functional recovery was assessed with Rota-rod test and grid walking task. The expression of growth-associated protein 43 (GAP43) and biotinylated dextran amine (BDA) was measured to evaluate axonal regeneration. The levels of cyclic AMP (cAMP) and PKA were measured by Elisa, PKAc and phosphorylated cAMP response element protein (pCREB) were determined by western blot. Our results shown that GRb1 treatment improved motor function and increased the expression of GAP43 and BDA in ipsilesional and contralateral cortex. GRb1 significantly elevated cAMP and PKA, increased the protein expression of PKAc and pCREB. However, the effects of GRb1 were eliminated by H89 intervention (a PKA inhibitor). These results suggested that GRb1 improved functional recovery in post-stroke by stimulating axonal regeneration and brain repair. The underlying mechanism might be up-regulating the expression of cAMP/PKA/CREB pathway.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31874020

RESUMO

Thermoradiotherapy acts as an important antitumor modality because heating can increase the blood flow and improve the oxygen level in tumor, thus remission of hypoxia-associated resistance for radiotherapy (RT). However, most agents for thermoradiotherapy are used either in the first near-infrared biological window or low photothermal conversion efficiency. Here, a facile method to prepare CuxS/Au nanocomposites via reduction methods from CuxS templates in mild synthetic conditions (i.e., aqueous solution and room temperature) is presented. After the growth of Au nanoparticles, the CuxS/Au nanocomposites have greater benefits for photothermal efficiency than that of CuxS nanoparticles due to the enhanced absorbance in the second near-infrared window. Moreover, biocompatibility and stability of these nanocomposites are greatly improved by lipoic acid poly(ethylene glycol). After the tumors were irradiated with a 1064 nm laser, their oxygenation status is subsequently improved, and the combination of photothermal therapy and RT achieves remarkable synergistic therapeutic effects. This work provides a novel idea to design a new-generation nanomedicine for tumor thermoradiotherapy.

4.
Amino Acids ; 52(1): 87-102, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31875259

RESUMO

Type 2 Diabetes causes learning and memory deficits that might be mediated by hippocampus neuron apoptosis. Studies found that taurine might improve cognitive deficits under diabetic condition because of its ability to prevent hippocampus neuron apoptosis. However, the effect and mechanism is not clear. In this study, we explore the effect and mechanism of taurine on inhibiting hippocampus neuron apoptosis. Sixty male Sprague-Dawley rats were randomly divided into control, T2D, taurine treatment (giving 0.5%, 1%, and 2% taurine in drinking water) groups. Streptozotocin was used to establish the diabetes model. HT-22 cell (hippocampus neurons line) was used for in vitro experiments. Morris Water Maze test was used to check the learning and memory ability, TUNEL assay was used to measure apoptosis and nerve growth factor (NGF); Akt/Bad pathway relevant protein was detected by western blot. Taurine improved learning and memory ability and significantly decreased apoptosis of the hippocampus neurons in T2D rats. Moreover, taurine supplement also inhibited high glucose-induced apoptosis in HT-22 cell in vitro. Mechanistically, taurine increased the expression of NGF, phosphorylation of Trka, Akt, and Bad, as well as reduced cytochrome c release from mitochondria to cytosol. However, beneficial effects of taurine were blocked in the presence of anti-NGF antibody or Akt inhibitor. Taurine could inhibit hippocampus neuron apoptosis via NGF-Akt/Bad pathway. These results provide some clues that taurine might be efficient and feasible candidate for improvement of learning and memory ability in T2D rats.

5.
DNA Cell Biol ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31821009

RESUMO

Hippo signaling regulates the balance between cell proliferation and apoptosis to control the size of organs during development. Appropriate Hippo signaling is associated with stem cell differentiation, and inappropriate signaling can result in tumorigenesis and cancer. Hippo signaling activity is influenced not only by biochemical signals but also by mechanical force and the cytoskeleton transmitted through cell-cell junctions and cell-matrix adhesions. In this review, we describe the evidence for the regulation of Hippo signaling by the spatial reorganization of signaling components, mechanical force, and the cytoskeleton. Although our understanding of the relationship between Hippo signal transduction and mechanical force and the cytoskeleton is developing rapidly, many unresolved questions remain.

6.
mSystems ; 4(6)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822599

RESUMO

Due to the limitations of effective treatments, avian influenza A H5N1 virus is the most lethal influenza virus strain that causes severe acute lung injury (ALI). To develop effective drugs ameliorating H5N1-induced ALI, we explore an RNA interference (RNAi) screening method to monitor changes in cell death induced by H5N1 infection. We performed RNAi screening on 19,424 genes in A549 lung epithelial cells and examined cell death induced by H5N1 infection. These screens identified 1,137 host genes for which knockdown altered cell viability by over 20%. DrugBank searches of these 1,137 host genes identified 146 validated druggable target genes with 372 drug candidates. We obtained 104 commercially available drugs with 65 validated target genes and examined their improvement of cell viability following H5N1 infection. We identified 28 drugs that could significantly recover cell viability following H5N1 infection and tested 10 in an H5N1-induced-ALI mouse model. The neurological drug ifenprodil and the anticancer drug flavopiridol markedly decreased leukocyte infiltration and lung injury scores in infected mouse lungs, significantly ameliorated edema in infected mouse lung tissues, and significantly improved the survival of H5N1-infected mice. Ifenprodil is an antagonist of the N-methyl-d-aspartate (NMDA) receptor, which is linked to inflammation and lung injury. Flavopiridol is an inhibitor of cyclin-dependent kinase 4 (CDK4), which is linked to leukocyte migration and lung injury. These results suggest that ifenprodil and flavopiridol represent novel remedies against potential H5N1 epidemics in addition to their proven indications. Furthermore, our strategy for identifying repurposable drugs could be a general approach for other diseases.IMPORTANCE Drug repurposing is a quick and economical strategy for developing new therapies with approved drugs. H5N1 is a highly pathogenic avian influenza virus subtype that can cause severe acute lung injury (ALI) and a high mortality rate due to limited treatments. The use of RNA interference (RNAi) is a reliable approach to identify essential genes in diseases. In most genomewide RNAi screenings, virus replication is the readout of interference. Since H5N1 virus infection could induce significant cell death and the percentage of cell death is associated with virus lethality, we designed a genomewide RNAi screening method to identify repurposable drugs against H5N1 virus with cell death as the readout. We discovered that the neurological drug ifenprodil and the anticancer drug flavopiridol could effectively ameliorate murine ALI after influenza A H5N1 virus infection, suggesting that they might be novel remedies for H5N1 virus-induced ALI in addition to the traditional indications.

7.
Sci Total Environ ; : 135752, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31791774

RESUMO

In light of environmental deterioration in coastal areas, deep sea cage aquaculture is becoming an increasingly attractive mode of mariculture. A key factor in determining the potential of deep sea cage aquaculture is to evaluate the environmental impacts of these practices. Here, a numerical model consisting of coupled hydrodynamic-, tracer-tracking- and 3-D Lagrangian particle-tracking models was set up and applied to evaluate the environmental impacts of deep sea cage cultivation of sea bass (Lateolabrax japonicus) in the Yellow Sea, China. The model was verified using water level data on August 1-31, 2018 and nutrient concentration in water and surface sediments in May, August, and November 2018, and January 2019. Results show that the model successfully captures the characteristics of local tidal currents and the total particulate nitrogen and phosphorus concentrations of the underlying sediments. Water quality simulations indicate that deep sea cages account for 26% of the total dissolved inorganic nitrogen and 19% of the active phosphorus content. Residual feed particles are predicted to fall in an ellipse centered on the cage location, with a long axis of 200 m and a short axis of 50 m. Feces are predicted to fall in an ellipse with a long axis of 1400 m and a short axis of 600 m. The Superposition particles are predicted to settle in an ellipse with a long axis of 320 m and a short axis of 150 m. The model results indicate that installation of all deep sea cages will lead to acceptable levels of water quality, but that sediments may become polluted. The coupled model can be used to predict the environmental impacts of deep sea cage farming and provide a useful tool for designing the layout of integrated multi-trophic aquaculture of organic extractive or inorganic extractive species.

8.
J Pept Sci ; 25(12): e3220, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31858653

RESUMO

Bacterial resistance induced by the use of antibiotics has provided a chance for the development of antimicrobial peptides (AMPs), and modification of AMPs to enhance the antibacterial activity or stability has become a research focus. PMAP-37 is an AMP isolated from porcine myeloid marrow, and studies on its modification have not yet been reported. In this study, three PMAP-37 analogs named PMAP-37(F9-R), PMAP-37(F34-R), and PMAP-37(F9/34-R) were designed by residue substitution to enhance the positive charge. The antimicrobial activity of PMAP-37 and its analogs in vitro and in vivo were detected. The results showed that compared with PMAP-37, PMAP-37(F9-R) and PMAP-37(F9/34-R) exhibited antibacterial activity against S. flexneri CICC21534. Although PMAP-37(F34-R) had no antibacterial activity against S. flexneri CICC21534, its minimal inhibitory concentrations (MICs) were significantly lower than those of PMAP-37 against most bacterial strains. Besides, all PMAP-37 analogs were pH stable, retaining stable antibacterial activity after treatment with solution from pH 2 to pH 8/9. In addition, the PMAP-37 analogs displayed increased thermal stability, and PMAP-37(F34-R) retained >60% antibacterial activity after boiling for 2 hours. Furthermore, the PMAP-37 analogs exhibited impressive therapeutic efficacy in bacterial infections by reducing bacterial burden and inflammatory damage in the lung and liver, resulting in a reduction in mortality. Notably, the therapeutic effect of PMAP-37(F34-R) was comparable to that of ceftiofur sodium, and even superior to antibiotics in L. monocytogenes CICC21533 infection model. In conclusion, the PMAP-37(F34-R) may be a candidate for the treatment of bacterial infections in the clinic.

9.
World J Surg Oncol ; 17(1): 221, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842912

RESUMO

BACKGROUND: The morbidity of thyroid carcinoma has been rising worldwide and increasing faster than any other cancer type. The most common subtype with the best prognosis is papillary thyroid cancer (PTC); however, the exact molecular pathogenesis of PTC is still not completely understood. METHODS: In the current study, 3 gene expression datasets (GSE3678, GSE3467, and GSE33630) and 2 miRNA expression datasets (GSE113629 and GSE73182) of PTC were selected from the Gene Expression Omnibus (GEO) database and were further used to identify differentially expressed genes (DEGs) and deregulated miRNAs between normal thyroid tissue samples and PTC samples. Then, Gene Ontology (GO) and pathway enrichment analyses were conducted, and a protein-protein interaction (PPI) network was constructed to explore the potential mechanism of PTC carcinogenesis. The hub gene detection was performed using the CentiScaPe v2.0 plugin, and significant modules were discovered using the MCODE plugin for Cytoscape. In addition, a miRNA-gene regulatory network in PTC was constructed using common deregulated miRNAs and DEGs. RESULTS: A total of 263 common DEGs and 12 common deregulated miRNAs were identified. Then, 6 significant KEGG pathways (P < 0.05) and 82 significant GO terms were found to be enriched, indicating that PTC was closely related to amino acid metabolism, development, immune system, and endocrine system. In addition, by constructing a PPI network and miRNA-gene regulatory network, we found that hsa-miR-181a-5p regulated the most DEGs, while BCL2 was targeted by the most miRNAs. CONCLUSIONS: The results of this study suggested that hsa-miR-181a-5p and BCL2 and their regulatory networks may play important roles in the pathogenesis of PTC.

10.
J Exp Clin Cancer Res ; 38(1): 501, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31864387

RESUMO

BACKGROUND: Esophageal cancer is one of the most common malignant tumors in the world. With currently available therapies, only 20% ~ 30% patients can survive this disease for more than 5 years. TRAIL, a natural ligand for death receptors that can induce the apoptosis of cancer cells, has been explored as a therapeutic agent for cancers, but it has been reported that many cancer cells are resistant to TRAIL, limiting the potential clinical use of TRAIL as a cancer therapy. Meanwhile, Periplocin (CPP), a natural compound from dry root of Periploca sepium Bge, has been studied for its anti-cancer activity in a variety of cancers. It is not clear whether CPP and TRAIL can have activity on esophageal squamous cell carcinoma (ESCC) cells, or whether the combination of these two agents can have synergistic activity. METHODS: We used MTS assay, flow cytometry and TUNEL assay to detect the effects of CPP alone or in combination with TRAIL on ESCC cells. The mechanism of CPP enhances the activity of TRAIL was analyzed by western blot, dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP) assay. The anti-tumor effects and the potential toxic side effects of CPP alone or in combination with TRAIL were also evaluated in vivo. RESULTS: In our studies, we found that CPP alone or in combination with TRAIL could inhibit the proliferation of ESCC cells and induce apoptosis, and we certificated that combination of two agents exert synergized functions. For the first time, we identified FoxP3 as a key transcriptional repressor for both DR4 and DR5. By down-regulating FoxP3, CPP increases the expression of DR4/DR5 and renders ESCC cells much more sensitive to TRAIL. We also showed that CPP reduced the expression of Survivin by inhibiting the activity of Wnt/ß-catenin pathway. All these contributed to synergistic activity of CPP and TRAIL on ESCC cells in vitro and in vivo. CONCLUSION: Our data suggest that CPP and TRAIL could be further explored as potential therapeutic approach for esophageal cancer.

11.
J Dermatolog Treat ; : 1-6, 2019 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-31865824

RESUMO

Background: The present study evaluates the effectiveness of fractional carbon dioxide (CO2) laser for the treatment of burn scars.Method: Literature search was conducted in electronic databases and studies were selected by following pre-determined eligibility criteria. Random effect meta-analyses were performed to achieve the effect size of the changes (mean difference (MD) between post-treatment and pretreatment values) in selected scar assessment scale scores and other important outcome measures.Results: 14 studies were included. Treatment of burn scars with fractional CO2 laser significantly improved Vancouver Scar Scale (MD -3.01 [95% confidence interval (CI) -3.79, -2.22]; p ˂ .00001), Patient and Observer Scar Assessment Scale (POSAS)- Patient (MD -14.38 [95% CI -17.62, -11.13]; p ˂ .00001, POSAS - Observer (MD -8.81 [9% CI -11.60, -6.02]; p ˂ .00001 and Scar Assessment Scale (MD 1.64 [95% CI 0.49, 2.78]; p = .005) scores especially with regards to pigmentation, vascularity, pliability, and height of scar. Pain and pruritis also improved with this treatment. Scar thickness measured with ultrasonography decreased non-significantly (MD -0.48 [95% CI -1.04, 0.09]; p = .1) whereas cutometer measures, R0 (scar firmness) and R2 (scar elasticity) did not change meaningfully.Conclusion: Fractional CO2 laser therapy is a valuable tool for the treatment of burn scars which has potential for reducing scar severity.

12.
Int J Biol Macromol ; 145: 492-499, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31883896

RESUMO

The modified agars were prepared using H2O2 in ethanol solution at appropriate pH conditions. Some interesting physical and chemical properties of modified agar were determined and characterized compared with those of raw agar, and the underlying mechanisms were preliminarily studied. Results showed that the maximum gel strength of the modified agar was 1068 g/cm2, which increased by 30.9% compared with that of raw agar (816 g/cm2), and the minimum sulfate content of the modified agar was 0.21%, which decreased by 73.4% compared with that of raw agar (0.79%). Moreover, the viscosity, molecular weight, gelling temperature and melting temperature all decreased, whereas the whiteness and transparency increased after modification. Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis indicated that the spatial structure of agar have changed after treated with H2O2. Taken together, the results demonstrated that the desulfation of agar with H2O2 is a promising approach with practical significance.

13.
Neurophotonics ; 6(4): 045003, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31673566

RESUMO

We explore cortical microvasculature changes during the progression of atherosclerosis using young and old transgenic atherosclerotic (ATX) mice with thinned-skull cranial window. In awake animals, exploiting intrinsic signal optical imaging, Doppler optical coherence tomography, and two-photon microscopy, we investigate how the progression of atherosclerotic disease affects the morphology and function of cortical microvasculature as well as baseline cerebral tissue oxygenation. Results show that aged ATX mice exhibited weaker hemodynamic response in the somatosensory cortex to whisker stimulation and that the diameter of their descending arterioles and associated mean blood flow decreased significantly compared with the young ATX group. Data from two-photon phosphorescence lifetime microscopy indicate that old ATX mice had lower and more heterogeneous partial pressure of oxygen ( PO 2 ) in cortical tissue than young ATX mice. In addition, hypoxic micropockets in cortical tissue were found in old, but not young, ATX mice. Capillary red blood cell (RBC) flux, RBC velocity, RBC velocity heterogeneity, hematocrit, and diameter were also measured using line scans with two-photon fluorescence microscopy. When compared with the young group, RBC flux, velocity, and hematocrit decreased and RBC velocity heterogeneity increased in old ATX mice, presumably due to disturbed blood supply from arterioles that were affected by atherosclerosis. Finally, dilation of capillaries in old ATX mice was observed, which suggests that capillaries play an active role in compensating for an oxygen deficit in brain tissue.

14.
Cancer Manag Res ; 11: 7909-7923, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31692549

RESUMO

Background: Hepatoma-derived growth factor (HDGF) is a heparin-binding protein that has been observed to be abnormally expressed in numerous malignancies, but the definite role of HDGF in bladder cancer (BCa) has not been clarified. Here, we conduct the present study to evaluate correlations between HDGF and BCa. Methods: Bioinformatics analysis was used to evaluate HDGF expression levels in BCa tissues. The effect of HDGF on cell proliferation, migration, invasion, cell cycle and apoptosis was analyzed utilizing CCK-8, clone formation, Transwell assays and flow cytometry, respectively. In addition, the xenograft tumor model was established. Results: Based on bioinformatics analysis, we noticed that HDGF was highly expressed in BCa tissues and was positively correlated with poor prognosis in patients. Knockdown of HDGF markedly reduced tumorigenesis in BCa cells. Furthermore, the results of flow cytometry showed that HDGF deletion enhanced apoptosis in T24 and 253J cells and led to cell cycle arrest in G1 phase. In further studies, we found that tumor growth was inhibited in xenograft nude mouse models with HDGF deletion. The results of RNA-seq analysis revealed that the PI3K-AKT signaling pathway-related genes were obviously changed in HDGF-deficient 253J cells, and this result was further confirmed by Western blot analysis. Conclusion: In summary, we suggest that HDGF plays a substantial role in BCa and promotes tumor development and progression by regulating the PI3K-AKT signaling pathway, which provides a promising target for BCa treatment.

15.
J Am Heart Assoc ; 8(22): e012885, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31718447

RESUMO

Background Inflammation is recognized as an important contributor of ischemia/reperfusion (I/R) damage after ischemic stroke. Sphingomyelin synthase 2 (SMS2), the key enzyme for the biosynthesis of sphingomyelin, can function as a critical mediator of inflammation. In the present study, we investigated the role of SMS2 in a mouse model of cerebral I/R. Methods and Results Cerebral I/R was induced by 60-minute transient middle cerebral artery occlusion in SMS2 knockout (SMS2-/-) mice and wild-type mice. Brain injury was determined by neurological deficits and infarct volume at 24 and 72 hours after transient middle cerebral artery occlusion. Microglia activation and inflammatory factors were detected by immunofluorescence staining, flow cytometry, western blot, and RT-PCR. SMS2 deficiency significantly improved neurological function and minimized infarct volume at 72 hours after transient middle cerebral artery occlusion. The neuroprotective effects of SMS2 deficiency were associated with (1) suppression of microglia activation through Toll-like receptor 4/nuclear factor kappa-light-chain-enhancer of activated B cells pathway and (2) downregulation of the level of galactin-3 and other proinflammatory cytokines. The mechanisms underlying the beneficial effects of SMS2 deficiency may include altering sphingomyelin components in lipid raft fractions, thus impairing the recruitment of Toll-like receptor 4 to lipid rafts and subsequently reducing Toll-like receptor 4/myeloid differentiation factor 2 complex formation on the surface of microglia. Conclusions SMS2 deficiency ameliorated inflammatory injury after cerebral I/R in mice, and SMS2 may be a key modulator of Toll-like receptor 4/nuclear factor kappa-light-chain-enhancer of activated B cells activation by disturbing the membrane component homeostasis during cerebral I/R.

16.
Mikrochim Acta ; 186(12): 771, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31720853

RESUMO

A ratiometric electrochemiluminescent (ECL) assay is described for the determination of the calcium(II) regulator calcitonin (CT). The method is making use of (a) graphite-like carbon nitride (g-C3N4) as the cathodic luminophore, (b) N-(aminobutyl)-N-(ethylisoluminol) (ABEI) as the anodic luminophore, and (c) peroxodisulfate and dissolved oxygen as coreactants. The luminous potential of g-C3N4 and ABEI can be well distinguished because of their different luminescent properties. Energy transfer between g-C3N4 and ABEI is not observed, and the coreactants peroxodisulate and oxygen do not interfere with each other. Au nanoparticles were functionalized with g-C3N4 and placed on the electrode to serve as a matrix for immobilization of primary antibody (Ab1). In the presence of CT, it will bind to the electrode. Then secondary antibody (Ab2) modified with polyaniline (PANI) and ABEI is incubated onto the electrode. With the increase in the concentration of CT, the blue ECL of g-C3N4 is quenched by PANI, while the blue luminescence of ABEI is enhanced. This enables ratiometric detection of calcitonin by ratioing the internsities at 460 and 475 nm. Response is linear in the 0.1~40 pg·mL-1 CT concentration range, and the limit of detection is 23 fg·mL-1. The method breaks the limitation of common ECL ratiometric strategy, namely, two luminophores often share the common coreactant. Graphical abstractSchematic representation of an immunoassay where polyaniline (PANI) in a BSA-Ab2-ABEI-Au@PANI composite quenches the cathodic signal of a graphitic carbon nitride (Au-g-C3N4) modified with gold nanoparticles (Au), while N-(aminobutyl)-N-(ethylisolumino) (ABEI) in the BSA-Ab2-ABEI-Au@PANI composit produces an anodic signal that enables quantitation of calcitonin.

17.
Genomics ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756427

RESUMO

Sweetpotato (Ipomoea batatas L.) is one of the most important food and grain-forage crops globally. It has been planted in >100 countries. Due to the complexity of the sweetpotato genome, its research is far behind other major food crops. At present, limited information about the sweetpotato genome is available. Thus, it is central to find an efficient approach for the investigation of sweetpotato genome. In this study, RAD-seq (Restriction site-associated DNA sequencing) was used to evaluate sweetpotato genetic structure diversity and to develop relevant SSR markers. The study yielded >128 Gb reliable sequence data from 81 sweetpotato accessions. By analyzing polymorphic tags from each accession, a total of 55,622 restriction-site associated DNA sequencing tags (RAD-seq) were found, containing 907,010 SNP. Genetic analysis divided 81 accessions into five major clusters based on their SNP genotype, which matches the results of genetic analysis and the genetic family tree. In addition, 18,320 SSRs loci were detected and 9336 SSR primer pairs were developed. Eighty-three primer pairs were amplified in different sweetpotato genotypes, 76 of which successfully amplified polymorphism bands. These results provide significant information about sweetpotato genome, which can be used to identify novel gene and to further develop the gene chip. And more significant, clustering results based on the SNP genotype provide an essential reference for breeders to match parent plants in breeding program. Additionally, SSR markers developed in this study will supply a wealth of markers for marker-assisted selection in sweetpotato breeding.

18.
J Hazard Mater ; : 121510, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31704120

RESUMO

Graphene oxide (GO)-anisotropic noble metal hybrid systems were developed as highly sensitive and reproducible surface enhanced Raman scattering (SERS) platform, in which ultrathin GO was embedded between two metallic layers of flower-like Ag nanoparticles (AgNFs) and gold nanostars (AuNSts). Due to multi-dimensional plasmonic coupling effect, the well-designed AgNFs-GO-AuNSts sandwich structures possessed ultrahigh sensitivity with the detection limit of R6G as low as 1.0 × 10-13 M and high enhancement factor of 2.59 × 107. Additionally, the GO interlayer could function as protective shell to suppress the oxidation of bottom silver layer and efficiently position the target analytes within hot spots. These features endow the substrate with high stability and excellent reproducibility (Signal variations < 7%). Particularly, the GO sandwiched substrate can be explored for the direct capture and sensitive detection of polychlorinated biphenyls (PCBs) without any organic modifier as molecule harvester. This minimum detected concentration was estimated as low as 3.4 × 10-6 M. The detection method based on GO mediated sandwich substrate avoids complicated surface modification manipulations and improves the substrate cleanness. Moreover, the resultant sandwich substrates can be used to recognize fingerprint peaks of different PCBs in their complex mixture, revealing great potential applications in SERS-based simultaneous detection of multiple pollutants with low affinity.

19.
Pathol Oncol Res ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748879

RESUMO

Previous studies indicated that cyclin D1 shown the potential as a tumor biomarker. However, the prognostic value of cyclin D1 in renal cell carcinoma (RCC) remains controversial. This study investigated the correlation of cyclin D1 expression with the prognostic and clinicopathological features in RCC patients. We systematically searched the database of PubMed, Embase, Cochrane, and Web of Science updated on November 26, 2017. Eighteen studies with 2282 patients satisfied the inclusion criteria. Results demonstrated that cyclin D1 overexpression in RCC showed significant favorable prognostic impact on disease-free survival (DFS) (HR 0.57, 95% CI: 0.43-0.74) and disease-specific survival (DSS) (HR 0.59, 95% CI 0.41-0.85) without significant heterogeneity. In subgroup of clear cell RCC, the prognostic effect on DFS was robust and the pooled HR was 0.39 (95% CI: 0.27-0.57). However, no association between overall survival (OS) and cyclin D1 expression was observed. Stratified analysis in DFS studies by sample size, staining patterns race and metastasis status showed similar results. Otherwise, cyclin D1 overexpression predicted a reduced prevalence of high TNM stage (T3 + T4) (OR 0.63, 95% CI: 0.40-0.99), high-grade tumor (G3 + G4) (OR 0.51, 95% CI: 0.31-0.81) and large tumor size (OR 0.35, 95% CI: 0.19-0.62). Our meta-analysis indicated that cyclin D1 overexpression could predict the favorable prognosis in patients with RCC.

20.
Opt Express ; 27(20): 27979-27990, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684557

RESUMO

We report the design of an elliptical-core five-mode group selective photonic lantern (EC-F-MGS-PL) supporting ten spatial modes over the C-band, whose output fiber is an elliptical-core few mode fiber (EC-FMF). Initially, we fix the cladding diameters of all input fibers to form an elliptical structure. With the help of beam propagation methods (BPM), we carry out comprehensive geometrical optimization of various input fiber bundle, and identify the optimal setting of input fiber bundle in order to achieve the maximum mode selectivity, low insertion loss (IL), and high mode conversion efficiency (MCE) for all five mode groups. Next, we optimize each fiber core diameter and propose a two-step tapering process, for the ease of performance enhancement for the EC-F-MGS-PL. Finally, the mode field evolution and the wavelength dependent operation of the proposed EC-F-MGS-PL is numerically investigated. A mode selectivity of 9∼17 dB and IL of 0.1∼0.38 dB for all five mode groups can be achieved over the C-band, while MCE keeps between 83.3%-95.8%. By taking into account of the fabrication process, we believe that both the design strategy and optimization procedure of the EC-F-MGS-PL are helpful for the implementation of multi-input-multi-output (MIMO)-less mode division multiplexing (MDM) transmission.

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