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1.
Talanta ; 207: 120280, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594565

RESUMO

Thrombin and its aptamers have been well studied and widely used as models in aptamer based assays and sensors. Here we reported a thrombin-linked sandwich immunoassay for proteins to demonstrate new applications of thrombin and the aptamers, converting protein detection to analysis of thrombin label. In this assay, target protein was sandwiched by the capture antibody on a microplate and the biotinylated detection antibody. Thrombin bound to one biotinylated aptamer, and then the thrombin-labeled aptamer was attached on the sandwich complex through streptavidin-biotin interaction by using streptavidin as a linker. Thrombin catalyzed cleavage of fluorogenic peptide substrates, generating fluorescence signals for target detection. Among a few different anti-thrombin aptamers, the use of one nuclease resistant RNA aptamer having phosphorodithioate (PS2) modification on a specific backbone position enabled higher assay sensitivity due to its much higher affinity. This thrombin-linked sandwich immunoassay allowed detection of prostate-specific antigen (PSA) at 2 pM, an important protein related cancer disease, with high sensitivity and specificity. The strategy was general, and also enabled sensitive detection of botulinum neurotoxin type A (BoNTA) light chain, one toxin protein causing risk to human health. This assay combines advantages of antibody recognition, aptamer affinity labeling, high affinity of aptamers, and enzyme activity of thrombin. Labeling thrombin on the immunosandwich complex through simple affinity binding overcomes limitations of covalent conjugating enzyme on antibody in conventional immunoassay. This assay is promising in applications for protein detection.

2.
J Hazard Mater ; 382: 121083, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472464

RESUMO

Bi4O5I2 loaded anatase-TiO2 (B) biphase nanowires composite photocatalysts were fabricated by an in situ calcination method and exhibited outstanding photocatalytic activity. The microstructure, optical performance and band structure of the composite photocatalysts were investigated by relevant characterizations. The results demonstrated the successful formation of heterojunction between anatase-TiO2 (B) biphase nanowires and Bi4O5I2, which integrated the advantages of homojunction and heterojunction. Therefore, it definitely improved separation efficiency of photo-induced electron-holes because of the formation of multi-junctions. In order to test the enhanced photocatalytic activity, acetaminophen was chosen as target pollutant. The sample with 67% Bi4O5I2 (TiO2-Bi4O5I2-3) presented the highest photocatalytic activity on the degradation of acetaminophen and its reaction apparent rate constant was 10 and 25 times as that of Bi4O5I2 and TiO2 biphase nanowires, respectively. Through trapping experiments and LC-MS/MS analysis, OH was proved to be the key active specie during the photocatalytic process of acetaminophen degradation. Meanwhile a possible degradation pathway was proposed based on the detected intermediate products.

3.
J Nanosci Nanotechnol ; 20(6): 3373-3377, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748029

RESUMO

The hepatocellular carcinoma (HCC) is a malignant tumor that occurs in the liver. It is a common malignant tumor in clinic. The main reason for its high mortality is its early latency. Therefore, how to accurately determine and test the hepatocellular carcinoma in the early stage has a very positive significance for the treatment. It is an important method for the early diagnosis of the hepatocellular carcinoma to use aptamers specifically binding to hepatocellular carcinoma cells, which has good application prospects. In order to improve the efficiency of aptamer selection of tumor cells, our group designed and developed an automated instrument for the aptamer selection. In this paper, the method to separate bound aptamers from the surface of HepG2 cells in automated selection process was studied, and the feasibility of separating binding aptamers from the HepG2 cell surface using ultrapure water and the effect of different temperature environments on its isolation were discussed. Results of the real-time fluorescent PCR and flow cytometry showed that ultrapure water could be used to isolate bound HepG2 cells and aptamers, and the concentration of the aptamers increased with the rise of the temperature between 25 and 80 degrees Celsius. This result will contribute to the improvement on the efficiency of automated selections for aptamers corresponding to HepG2 cells.

4.
J Biomed Mater Res A ; 108(1): 50-60, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31443121

RESUMO

The scaffold-free cell sheet plays an important role in stem-cell-based regeneration. Graphene oxide (GO) endows nanoparticles (NPs) with special characteristics and therefore has attracted increasing attention in recent years. However, the existence of toxicity in GO and its derivatives limits their ability to promote osteogenic differentiation. Magnetic graphene oxide (MGO), a novel combination of Fe3 O4 and GO with diverse unique properties, has not been studied in bone tissue engineering. In this study, MGO was fabricated, and the previously undiscovered relationships-including cellular behavior and the effects of osteogenic differentiation and related mechanisms of MGO in rat bone-marrow-derived mesenchymal stem cells (BMSCs)-were investigated for the first time. Here, we found that MGO was not only biocompatible at low concentrations, but also could significantly accelerate osteogenic differentiation in BMSCs. Both the cellular behavior and bone-formation differentiation in BMSCs treated with MGO showed concentration-dependent characteristics. In addition, the regulation of osteogenic differentiation in BMSCs treated with MGO might be involved with the Wnt/ß-catenin and BMP signaling pathways. Furthermore, MGO demonstrated a better ability for osteogenic differentiation in BMSCs than did GO. The current work indicated a significant use for MGO nanocomposite scaffolds in biocompatibility and bone regeneration, which could provide new insight into bone regeneration in the future.

5.
Comput Methods Programs Biomed ; 183: 105073, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31525548

RESUMO

BACKGROUND AND OBJECTIVE: Imaging genetics has been widely used to help diagnose and treat mental illness, e.g., schizophrenia, by combining magnetic resonance imaging of the brain and genomic information for comprehensive and systematic analysis. As a result, utilizing the correlation between magnetic resonance imaging of the brain and genomic information is becoming an important challenge. METHODS: In this paper, the joint analysis of single nucleotide polymorphisms and functional magnetic resonance imaging is conducted for comprehensive study of schizophrenia. We developed a deep canonically correlated sparse autoencoder to classify schizophrenia patients from healthy controls, which can address the limitation of many existing methods such as canonical correlation analysis, deep canonical correlation analysis and sparse autoencoder. RESULTS: The proposed deep canonically correlated sparse autoencoder can not only use complex nonlinear transformation and dimension reduction, but also achieve more accurate classifications. Our experiments showed the proposed method achieved an accuracy of 95.65% for SNP data sets and an accuracy of 80.53% for fMRI data sets. CONCLUSIONS: Experiments demonstrated higher accuracy of using the proposed method over other conventional models when classifying schizophrenia patients and healthy controls.

6.
J Nanosci Nanotechnol ; 20(2): 692-700, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383064

RESUMO

Fluorescent bimetallic Au-Ag nanoclusters (Au-AgNCs) were found to exhibit oxidase-like activity and could catalyze the oxidation of 3,3',5,5' tetramethylbenzidine (TMB) to oxTMB. On the basis of this property, we assembled a fluorescent nanoplatform as a turn-on probe for sensing mercury (II) ions (Hg2+) through the inner-filter effect (IFE). Au-AgNCs and oxTMB were chosen as IFE absorber and fluorophore pair for the first time. In the absence of Hg2+, the Au-AgNCs absorption band well. Covered the fluorescence emission band of oxTMB, and as a result, the fluorescence of oxTMB was reduced. In the presence of Hg2+, Hg2+ was reduced to Hg0 by extra BSA in Au-AgNCs probe system and anchored on the surface of Au-AgNCs. The absorption intensity for Au-AgNCs then decreased at 418 nm, resulting in the recovery of fluorescence from oxTMB. The formed Au-Hg thin amalgam layer obviously enhanced the oxidase-like activity of Au-AgNCs as well as hindered the IFE activity between Au-AgNCs and oxTMB. Therefore, based on the Hg2+ stimulating oxidaselike properties of Au-AgNCs, a fluorometric assay for determination of Hg2+ was developed in this study. The proposed sensing strategy showed a linear range from 10 nM to 500 nM, with ultralow LOD of ~0.7 nM for Hg2+. Moreover, the detection probe system was stable over a wide pH range, making it able to be applied in complex sample systems. We have successfully demonstrated the detection of Hg2+ in tap water samples. The fluorescent assay reported here, for sensitive and selective determination of Hg2+, may find great application in multiple areas, such as environmental and pharmaceutical analysis.

7.
J Nanosci Nanotechnol ; 20(4): 2138-2143, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492222

RESUMO

With the higher and higher application level of medical technology, more and more genetic diseases have been diagnosed. Nucleic acid, as an important genetic material, has been found to have important functions in the storage and transmission of the genetic information in the replication and synthesis of proteins. As the first step in nucleic acid detection experiments, nucleic acid extraction performance is associated with the purity of target nucleic acid samples, which is very important for the downstream steps. In this paper, we employed the magnetic bead for extracting nucleic acids based on the platform of large liquid handling workstation and designed a matching magnetic separation module. It was shown that the temperature control block designed in this paper has reliable stability, high accuracy by using the incremental PID algorithm, with the control accuracy up to ±0.5 °C, and the control stabilization time is about 90 s, which can satisfy the experimental requirements. Besides, the average magnetic bead transfer rate of this module was further verified by mimicking the manual magnetic bead nucleic acid extraction process. The results proved that the module has an excellent performance with the average magnetic bead transfer rate greater than 95% and the magnetic bead transfer rate in each well greater than 90%, which could be consistent with the experimental indictors of nucleic acid extraction.

8.
J Nanosci Nanotechnol ; 20(4): 2165-2170, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492225

RESUMO

The high-throughput nucleic acid detection system provides a good solution for detecting nucleic acids more safely, rapidly and accurately, which greatly improves the detection efficiency. Highthroughput nucleic acid detection mainly includes three steps: signal acquisition, signal amplification and signal processing. Therefore, obtaining the purified nucleic acid is the primary task of the nucleic acid detection, and the quality of the nucleic acid has a significant impact on results. In this paper, we employed the magnetic nanoparticle technology for extracting nucleic acids based on the platform of large liquid handling workstation and designed a matching vibrating module. The involved steps of core method, magnetic bead nucleic acid extraction technology, are mainly concerned with the cell lysis, nucleic acid binding, nucleic acid purification and magnetic particles elution. During the extraction process, specific temperature is required for the lysis and elution. It was shown that the temperature control part designed in this paper has the reliable stability, high accuracy by using the incremental proportion-integration-differentiation (PID) algorithm, with the control accuracy up to ±0.5 °C. The temperature regulating time is about 90 s, which can meet the experimental requirements. Besides, the vibrating uniformity of this module was further verified by protein concentration test, which proved that the module has the excellent performance and can be consistent with the experimental indictors of the nucleic acid extraction.

9.
J Nanosci Nanotechnol ; 20(3): 1332-1340, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492292

RESUMO

Nucleic acid aptamers are a kind of one-dimensional biological nanomaterials and have found many applications. This paper designed and implemented a polymerase chain reaction (PCR) amplification device with a reaction volume of 500 µL, which can be used for the amplification of nucleic acid aptamers of tumor cells in the aptamer selection. This device mainly includes a control module, a temperature measuring module, a PCR amplification tube, a metal tank module, a liquid crystal display (LCD) and operation module and a cooling module. The new PCR amplification chamber is matched with the designed metal tank to ensure the temperature uniformity of the PCR amplification solution. The control module based on the STM32F103RCT6 manages the workflow of the entire device. The PCR amplification chamber and PT100 sensors on the metal tank formed a closed-loop feedback system, and the incremental proportional-integral-derivative (PID) algorithm was used to achieve the precise temperature control. In addition, we introduced the Smith predictive compensation algorithm to solve the temperature hysteresis problem of the PCR amplification chamber. The experimental results showed that the PCR device can meet the requirements for the nucleic acid aptamer selection of tumor cells. The device can also be used in other experiments with large-volume PCR amplification.

10.
J Nanosci Nanotechnol ; 20(3): 1401-1408, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492300

RESUMO

In the automated high-throughput nucleic acid detection system, we need to grip and transfer consumables frequently when carrying out multichannel nucleic acid detection. In order to ensure the efficiency of experiments and solve problems of the deflection and drop when transferring microplates, we design a self-locking mechanical gripper which consists of a rotary positioning module and a gripping module. The absolute position encoder fixed on the top of the stepper motor can collect the position data of the mechanical gripper in real time and send them to the master control board based on STM32 for processing, which ensures the accuracy of the movement of the mechanical gripper. We used SolidWorks to build models of the mechanical gripper and different microplates, and we carried on finite element analysis of microplates to find the suitable gripping position. Through the force analysis, we obtained the pressure distribution and the deformation of different microplates, and defined the effective gripping areas, which is important to the grip and transfer of microplates.

11.
Food Chem ; 303: 125386, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473454

RESUMO

The present work investigated the influences of ultrahigh pressure (UHP), ultrasound (US) and their combination (UHP-US) as pretreatments on properties of vacuum-freeze dried strawberry slices. During vacuum-freeze drying, drying duration and total energy consumption of UHP sample, US sample and UHP-US sample was decreased. After the UHP or US pretreatments, a* value (redness), antioxidative substances (total anthocyanin content, total flavonoid content, total phenolic content, diphenyl picrylhydrazyl (DPPH), hydroxyl (-OH) radical-scavenging assay), hardness and cross-section areas of matrix in the dried slices were significantly (P < 0.05) increased. Transverse relaxation times and peak area corresponding to free water in the pretreated samples were obviously decreased, indicating lower mobility in the pretreated samples. As compared with UHP or US individually, UHP in combination with US increased those parameters more pronouncedly. Therefore, UHP and US are promising techniques for the vacuum-freeze drying processing of strawberry products.


Assuntos
Dessecação , Conservação de Alimentos/métodos , Fragaria/química , Frutas/química , Pressão , Ondas Ultrassônicas , Antocianinas/análise , Antioxidantes/análise , Antioxidantes/química , Cor , Flavonoides/análise , Liofilização , Frutas/efeitos da radiação , Fenóis/análise , Vácuo
12.
J Affect Disord ; 260: 18-23, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493633

RESUMO

BACKGROUND: Chronic exposure to stressful work environments can influence general trust. High job stress is associated with low trust in others. Both environmental and genetic factors contribute to general trust; however, few empirical studies have explored the important role of gene-environment interactions on general trust. In this study, the moderating roles of the polymorphisms OXTR rs53576 and OXTR rs2268490 in the relationship between job stress and general trust were evaluated. METHODS: 362 healthy Chinese Han university teachers (196 males, 165 females, and 1 undisclosed) were included (Mage = 39.80, SD = 9.16). Standardized questionnaires about demographic characteristics, job stress, and general trust scale were collected. Blood samples were collected for OXTR rs53576 and rs2268490 genotyping. RESULTS: Job stress scores showed a significant negative main effect on general trust (p < 0.001), while OXTR rs53576 and rs2268490 did not (p > 0.05). The effect of the interaction between job stress and OXTR rs53576 or rs2268490 on general trust was significant, even after controlling for gender and age. High job stress was associated with low general trust in OXTR rs53576 homozygous individuals (GG/AA) or OXTR rs2268490 CT individuals, demonstrating that the GA genotype in OXTR rs53576 and CC/TT genotype in OXTR rs2268490 are protective genotype of general trust. LIMITATIONS: This study used a cross-sectional design, only considered Chinese Han university teachers, and only examined two polymorphisms in OXTR. CONCLUSIONS: Our findings provide evidence that gene-environment interactions influence general trust and identify a new locus (rs2268490) underlying this phenotype.

13.
Environ Pollut ; : 113441, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31672370

RESUMO

Phosphorus (P) plays a critical role in eutrophication and algal growth; therefore, improving our understanding of the impact of P is essential to control harmful algal blooms. In this study, Microcystis aeruginosa was treated with 5-h ambient irradiation in the medium with different dissolved inorganic P (DIP) concentrations, DIP-free, moderate-DIP, and high-DIP, to explore its growth and other physiological responses. Compared to photosynthetically active radiation (PAR), UV-A (320-400 nm) and UV-B (280-320 nm) radiation had inhibitive effects on the photosynthesis and growth of M. aeruginosa, while high P availability could alleviate or eliminate the negative effects of UV radiation. The photosynthetic parameters had a minimum reduction and quickly recovered after re-inoculation under high-DIP conditions. Confirmed by SEM, photosynthetic pigments, the generation of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and other methods, ambient UV radiation exerted oxidative stresses rather than direct lethal effects on M. aeruginosa. Photosynthetic parameters indicated that algal UV-adaptation processes could include decreasing photo-induced damages and increasing self-repair efficiency. The P acquired by M. aeruginosa cells can have two function, which included alleviating UV-induced negative effects and sustaining algal growth. Consequently, UV-adaptation processes of M. aeruginosa resulted in an elevated demand for DIP, which resulted to increased P uptake rates and cellular P quota under moderate and high-DIP conditions. Therefore, the production of carotenoid and phycocyanin, and SOD activity increased under UV stress, leading to a better adaptation capability of M. aeruginosa and decreased negative effects of UV radiation on its growth. Overall, our findings demonstrated the significant interactive effects of P enrichment and irradiation on typical cyanobacteria, and the strong adaptation capability of M. aeruginosa in the eutrophic UV-radiated waters.

14.
Pediatr Neonatol ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31672476

RESUMO

BACKGROUND: Turner syndrome (TS) is characterized by growth failure, primary ovarian failure, cardiac anomalies, and other anomalies. Cardiovascular abnormalities such as bicuspid aortic valve (BAV), coarctation of the aorta (CoA), aortic stenosis (AS), and aortic dilatation (AD) account for some cases of TS-related early mortality. In this study, we investigated the correlations between cardiovascular phenotypes and karyotypes in TS. METHODS: We conducted a retrospective cohort analysis of 105 local patients with TS aged 6-43 years between January 1994 and December 2018. They were categorized into two groups of complete monosomy X (45,X) and other X chromosome abnormalities. Most of the patients underwent echocardiography (n = 88, 83.8%), cardiac computed tomography (CT) angiography, and/or cardiovascular magnetic resonance imaging (MRI) (n = 58, 55.2%). We used independent the Student's t test, chi-square test or Fisher's exact test, and log-rank test to compare differences in continuous data, proportions, and Kaplan-Meier survival analysis results between the two TS groups. RESULTS: 45,X was the most common karyotype (n = 47, 44.8%). Phenotypically, cardiovascular malformations were found in 29 patients with TS (27.6%). BAV (n = 6), CoA (n = 3), AS (n = 2), ASD (n = 1, 2.5%), and PAPVR (n = 1, 2.5%) were found in only the 45,X group. The mean age at AD onset was 25.55 ± 5.78 years (mean ± SD). Survival analysis of age at onset of AD demonstrated no significant difference between the two groups (p = 0.051). CONCLUSION: Cardiovascular abnormalities, such as BAV, CoA, AS, and AD, are common and potentially progressive in patients with TS, especially those with the 45,X karyotype. They should receive immediate cardiological assessments upon receiving diagnosis, regular assessments, and treatment to carefully control blood pressure, even with no apparent congenital heart disease.

15.
Opt Express ; 27(19): 26471-26482, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674528

RESUMO

Healthcare and biosensing have attracted wide attention worldwide, with the development of chip integration technology in recent decades. In terms of compact sensor design with high performance and high accuracy, photonic crystal structures based on Fano resonance offer superior solutions. Here, we design a photonic crystal structure for sensing applications by proposing modeling for a three-cavity-coupling system and derive the transmission expression based on temporal coupled-mode theory (TCMT). The correlations between the structural parameters and the transmission are discussed. Ultimately, the geometry, composed of an air mode cavity, a dielectric mode cavity and a cavity of wide linewidth, is proved to be feasible for simultaneous sensing of refractive index (RI) and temperature (T). For the air mode cavity, the RI and T sensitivities are 523 nm/RIU and 2.5 pm/K, respectively. For the dielectric mode cavity, the RI and T sensitivities are 145 nm/RIU and 60.0 pm/K, respectively. The total footprint of the geometry is only 14 × 2.6 (length × width) µm2. Moreover, the deviation ratios of the proposed sensor are approximately 0.6% and 0.4% for RI and T, respectively. Compared with the researches lately published, the sensor exhibits compact footprint and high accuracy. Therefore, we believe the proposed sensor will contribute to the future compact lab-on-chip detection system design.

16.
Int J Biol Macromol ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669464

RESUMO

This study mainly aimed to investigate the influents of high hydrostatic pressure (HHP) on the ordered structures of starch, for this purpose, we compared the ordered structure of rice starch treated by HHP and heat, including long- and short-range ordered structures and thermodynamic properties at similar levels of gelatinization degree (DG). X-ray diffractometer, Fourier transform infrared spectrometer (FTIR), 13C cross polarization magic angle spinning/NMR, and Differential scanning calorimeter were used to detect crystal structure, band height ratio in FTIR spectra (R), double helix structure, and thermodynamic behavior. Results showed that HHP-treated rice starch (HHGS) had greater crystallinity, larger R, and more double helix and V-type single helix structures as compared to heat-treated rice starch (HGS) at a similar DG. The thermodynamic analysis illustrated that To of HHGS was lower as compared to HGS. The ordered structure of HHGS was close packaged. HHP simultaneously induced annealing and pressure-induced gelatinization until achieving a certain degree of gelatinization.

17.
Waste Manag ; 102: 122-130, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31671359

RESUMO

Some inevitable issues of the acid leaching method used to recycle spent lithium-ion batteries (LIBs), such as toxic gas emission, excessive acid-base consumption, inferior metal selectivity and equipment corrosion, have gradually emerged and restricted the promotion and development of this method. It is therefore essential to develop a sustainable closed-loop recycling technology (reduction-ammoniacal method) for spent LIBs. In this study, the effects of various species of ammonia, ammonium salts and reductants on the leaching of Li, Co, Ni, Mn and Al from spent LIBs were investigated with a hydrothermal method. An increase of the electrode potential of the reductant greatly accelerated the selective leaching of Li, Co and Ni, which agreed with the thermodynamic analysis results. The standard electrode potentials of the LiNixCoyMn1-x-yO2 (NCM) materials were also determined by using approximate calculations. When using (NH4)2SO3 as a reductant in a one-step leaching process, 100% Co, 98.3% Ni and 90.3% Li were extracted into the ammonia-ammonium chloride solutions. From the kinetics analysis, the surface chemical reaction shrinking core model was found to control the leaching behavior of Li, Co, and Ni in the reduction-ammoniacal leaching process. A shell-core structure was composed of a product layer, a diffusion layer of the solid core and an unreacted core. Species in the product layer reduced the leaching efficiencies of Li, Co, and Ni. The results obtained for this hydrothermal reduction-ammoniacal method applied to recycle spent LIBs provide insights for the design of a high-speed, exceptionally selective, closed-loop recycling technique.

18.
Life Sci ; 239: 116774, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31689438

RESUMO

AIMS: Stroke is a refractory cerebral blood circulation disorder. Endothelial progenitor cells (EPCs) participate in the repair and regeneration of vascular injury through the combination of cell replacement and bystander effects. Here, we evaluated the biological function of EPCs in treating a mouse model of cerebral ischaemic stroke, using dual-mode bioluminescence and magnetic resonance imaging to trace EPCs in vivo. MAIN METHODS: We constructed a viral vector with a luciferase-enhanced green fluorescent protein (Luc-eGFP) reporter gene for bioluminescence imaging (BLI) detection, and simultaneously synthesized the magnetic resonance imaging (MRI) contrast agent, nano-sized superparamagnetic iron oxide (USPIO), to co-label human umbilical cord blood-derived EPCs (hEPCs). The labelled hEPCs were transplanted into mice with stroke, and the biological behaviours of the cells in-vivo were studied using BLI and MRI, and methods of molecular biology and histology. KEY FINDINGS: Comparing the two cell transplantation routes by BLI confirmed that many cells transplanted via the left ventricular route homed to ischaemic brain tissue. The dual-modality-imaging showed the prognosis of in-vivo tracking cells after transplantation in ischaemic tissues at different time points. Histological staining and neurological function scores confirmed that EPC transplantation can improve the symptoms of nerve deficit in the mouse stroke model. Histological staining revealed that cell transplantation can lead to recovery of neurological function after stroke, via various processes. These include reduced blood brain barrier permeability, recovery of white matter and of myelin, and the enhancement of neuroneogenesis. SIGNIFICANCE: Dual-modality imaging revealed EPCs as potential candidates for the treatment of ischaemic stroke.

19.
ACS Appl Mater Interfaces ; 11(47): 44170-44178, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31674753

RESUMO

Well-tailored sulfur-doped anatase titanium dioxide nanoparticles anchored on a large-area carbon sheet are designed, where the in situ sulfur-doped titanium dioxide directly comes from titanium oxysulfate and the large-area carbon sheet is derived from glucose. When applied as an anode material for sodium-ion batteries, it exhibits an excellent electrochemical performance including a high capacity [256.4 mA h g-1 at 2 C (1 C = 335 mA h g-1) after 500 cycles] and a remarkable rate of cycling stability (100.5 mA h g-1 at 30 C after 500 cycles). These outstanding sodium storage behaviors are ascribed to the nanosized particles (about 8-12 nm), good electronic conductivity promoted by the incorporation of carbon sheet and sulfur, as well as the unique chemical bond based on the electrostatic interaction.

20.
Chemosphere ; 243: 125336, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31734597

RESUMO

Fenvalerate (FEN), one of the most used synthetic pyrethroids, has the potential to interfere with human neural function. However, far too little attention was paid to the mechanism of FEN-induced neurotoxicity. Thus we exposed zebrafish to FEN from 4 to 120 h post fertilization (hpf), and analyzed the morphology and behavior of zebrafish. Our results showed that FEN decreased the survival rate of zebrafish, with increased malformation rates and abnormal behaviors. Furthermore, we found typical parkinson-like symptoms in FEN-exposed zebrafish with increases in parkinson's disease (PD), ubiquitin, and Lewy bodies-relevant genes. We also observed the loss of dopaminergic neurons in both FEN-exposed zebrafish and PC12 cells, which were all associated with PD-like symptoms. Besides, FEN activated autophagy by the enhanced expressions of p-mTOR, and LC3-II but the reduction of p62. Further, FEN initially activated p-p38 MAPK followed by p-mTOR, which triggered the transcription of genes responsible for autophagy process and prompted the Lewy bodies neuron generation leading to the PD-like symptoms. This process was inhibited by both 3-methyladenine (3-MA, an autophagy inhibitor) and SB203580 (a p38 MAPK selective inhibitor) in zebrafish and PC12 cells. These results suggest that FEN might cause parkinson-like symptom during zebrafish development through induction of autophagy and activation of p38 MAPK/mTOR signaling pathway. The study revealed the potential mechanism of FEN-induced neurotoxicity and should give new insights into a significant environmental risk factor of developing parkinson's disease.

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