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1.
Int J Biol Macromol ; 149: 1130-1138, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32001285

RESUMO

Magnetic graphene nanocomposites were prepared by hydrothermal synthesis, and aniline polymerization was initiated by magnetic graphene. These polyaniline/magnetic graphene (PANI/MG) composites were used to immobilize laccase to construct biosensors. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and infrared spectroscopy (IR) were used to characterize these composites. Cyclic voltammetry and chronoamperometry technique were used to test the electrical properties of the constructed polyaniline/magnetic graphene laccase modified electrode. The results show that the polyaniline/magnetic graphene immobilizing laccase modified electrode exhibited superior electrical properties, including high sensitivity, detection limit and linear range. The hydroquinone was used as an analytical and detection probe. The selectivity was 0.03639 A/(mol/L), the linear range was 0.4-337.2 µmol/L, and the detection limit was 2.94 µM (signal/noise = 3, minimum identification value of effective signal). The biosensor can reach the conditions for detecting the actual water sample.

2.
Int J Pharm ; 576: 119031, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31953082

RESUMO

This study developed novel ionic liquids (ILs) based on amino acids. We first screened 15 methyl amino acid ester hydrochlorides ([AAC1]Cl) for their skin permeation enhancements using 5-Fluorouracil (5-Fu) and Hydrocortisone (HC) as model drugs. Glycine methyl ester hydrochloride ([GlyC1]Cl), L-proline methyl ester hydrochloride ([L-ProC1]Cl), and L-leucine methyl ester hydrochloride ([L-LeuC1]Cl) were selected, and their ester sites were modified with different carbon chains (C8 and C12). The resulting ILs showed improved permeation to the two drugs. TEWL and CLSM assays revealed the moderation effects of the modified ILs on skin barrier function, whereas L-proline dodecyl ester hydrochloride ([ProC12]Cl) and L-leucine dodecyl ester hydrochloride ([L-LeuC12]Cl) exhibited the strongest activities. Permeation mechanisms were further investigated by ATR-FTIR, solid-NMR, SEM, and TEM analyses. The results suggested that [L-ProC12]Cl and [L-LeuC12]Cl combined the advantages of amino acid esters and IL solvent and could interact with the intercellular lipid domain by the multi-functions of lipid fluidization and lipid extraction, which were observed in a dosage- and time-dependent manner. Additionally, pathological examination suggested that the amino acid ester-based ILs (AAE-ILs) had good biocompatibility. In conclusion, this study has generated novel chemical penetration enhancers (CPEs) based on AAE-ILs and may be potentially utilized in drug transdermal delivery systems (TDDSs).

3.
J Colloid Interface Sci ; 561: 647-658, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31761469

RESUMO

Our aim is to develop a hydrogel-based scaffold containing porous microchannels that mimic complex tissue microarchitecture and provide physical cues to guide cell growth for scalable, cost-effective tissue repair. These hydrogels are patterned through the novel process of magnetic templating where magnetic alginate microparticles (MAMs) are dispersed in a hydrogel precursor and aligned in a magnetic field before hydrogel crosslinking and subsequent MAM degradation, leaving behind an aligned, porous architecture. Here, a protocol for fabricating uniform MAMs using microfluidics was developed for improved reproducibility and tunability of templated microarchitecture. Through iron quantification, we find that this approach allows control over magnetic iron oxide loading of the MAMs. Using Brownian dynamics simulations and nano-computed tomography of templated hydrogels to examine MAM chain length and alignment, we find agreement between simulated and measured areal densities of MAM chains. Oscillatory rheology and stress relaxation experiments demonstrate that magnetically templated microchannels alter bulk hydrogel mechanical properties. Finally, in vitro studies where rat Schwann cells were cultured on templated hydrogels to model peripheral nerve injury repair demonstrate their propensity for providing cell guidance along the length of the channels. Our results show promise for a micro-structured biomaterial that could aid in tissue repair applications.

4.
Phys Med Biol ; 65(2): 025014, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31766030

RESUMO

The dynamic magnetization of immobilized spherical single-domain magnetic nanoparticles (MNPs) with uniaxial or cubic magnetocrystalline anisotropy was studied computationally by executing simulations based on the Landau-Lifshitz-Gilbert (LLG) equation. For situations when a static magnetic field was suddenly applied and then removed, the effects of particle diameter and anisotropy (considering both type of symmetry and characteristic energy) on the characteristic magnetic relaxation time were studied parametrically. The results, for both anisotropy symmetries, show that when a static magnetic field is suddenly turned on or off the MNPs undergo a successive two-step or combined one-step relaxation. Whether a MNP relaxes with one or two steps when the field is turned on is determined by the competition between the energy of the applied magnetic field, the magnetic anisotropy energy, and thermal energy. When the applied magnetic field is suddenly turned off, our results show good agreement with theoretical predictions for the cases of [Formula: see text] and [Formula: see text], where [Formula: see text] represents the magnetic anisotropy energy barrier, [Formula: see text] is the Boltzmann constant and [Formula: see text] represents the absolute temperature. For the case of an applied alternating magnetic field (AMF) that is typical of magnetic particle imaging (MPI) applications, the effects of particle diameter and anisotropy symmetry were studied in terms of time-domain magnetization dynamics, dynamic hysteresis loops, harmonic spectra, and x-space point spread functions (PSFs). Results illustrate that the type of magnetocrystalline anisotropy (uniaxial versus cubic) has a significant effect on the MPI performance of the nanoparticles. These computational studies provide insight into the role of particle diameter and magnetic anisotropy on the performance of MNPs for applications in magnetorelaxometry and MPI.

5.
J Matern Fetal Neonatal Med ; 33(7): 1178-1190, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30153758

RESUMO

Background: Published data regarding the association between glutathione S-transferase M1 (GSTM1) and glutathione S-transferase T1 (GSTT1) gene polymorphisms and risk of low birth weight (LBW) remains inconclusive, and data on the interactions between the two gene polymorphisms and smoking for LBW susceptibility is lacking. To clarify these associations, a meta-analysis was conducted.Methods: A comprehensive literature search was conducted in multiple databases until 11 January 2018. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using fixed or random effects model.Results: Thirty-eight studies from 17 articles concerning maternal and neonatal GSTM1 and GSTT1 gene polymorphism with LBW risk were included in this meta-analysis, and nine studies from five articles provided data of maternal tobacco exposure status during pregnancy. Maternal GSTM1 null genotype was associated with increased LBW risk (OR = 1.27, 95% CI: 1.12-1.45). There was a nonsignificant but positive association (OR = 1.19, 95% CI: 0.97-1.46) between the maternal GSTT1 null genotype and the LBW risk in the overall analysis. There was a null association between neonatal GSTM1 or GSTT1 polymorphism and LBW risk. There were significant associations between the maternal GSTM1 null and GSTT1 null genotype and LBW risk (for the former, OR = 3.85, 95% CI: 1.68-8.81; for the later, OR = 1.88, 95% CI: 1.01-3.50) in individuals with active smoking, respectively.Conclusion: Maternal GSTM1 and GSTT1 null genotypes, but not neonatal genotypes, are suggested to increase LBW susceptibility, and there are interactions between active smoking and these polymorphisms in the development of LBW.

6.
Huan Jing Ke Xue ; 40(7): 3361-3368, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854739

RESUMO

Soil aggregates are important indicators of soil quality and sustainable land utilization, and impact the retention abilities of water and fertilizers and the release of nutrients in soil. This study aimed to understand the effects of two land use types (an orchard and farmland) on the distribution, stability, and organic carbon content of soil aggregates, and provides a theoretical basis for the optimal management of the soil carbon pool in the Weibei Dryland of the Loess Plateau. We examined the soils from an orchard and from farmland by simultaneous sampling and wet sieving; the proportions of large macroaggregates (>2 mm), small macroaggregates (0.25-2 mm), microaggregates (0.053-0.25 mm), and silt and clay (<0.053 mm) were then determined; the content of organic carbon in each aggregate fraction at soil depths of 0-40 cm were also measured, and the total organic carbon content of all aggregates fractions was determined for each soil. The results showed that the type of agricultural land use had a significant effect on the distribution and stability of soil aggregates in the 0-20 cm soil layer, with the relative proportions of the different sized aggregates (>2, 0.25-2, 0.053-0.25, and<0.053 mm) being 12.9%, 51.3%, 28.8%, and 7.0% in the orchards, respectively, and 8.3%, 49.7%, 33.6%, and 8.4% on the farmland, respectively. The proportion of macro-aggregates (>0.25 mm) was significantly higher in the orchard soils than in the farmland soils. Mean weight diameter (MWD) and geometric mean diameter (GMD) are important indicators of the soil aggregate stability; the MWD and GWD of the farmland soils were significantly lower than the orchard soils in the 0-40 cm depth zone (P<0.05). The effects of different land use types on the organic carbon content of soil aggregates was most marked in the 0-10 cm layer. Compared with farmland, the organic carbon content in the large aggregates, intermediate aggregates, micro-aggregates, and the silt and clay fraction of orchard soils were relatively increased by 56.0% (P<0.05), 57.1% (P<0.05), 40.8% (P>0.05), and 13.0% (P>0.05), respectively. Organic carbon storage in each aggregate class (excluding the<0.053 mm fraction) in the orchard soils was higher than in the farmland soils. In the orchard soils, the proportion of soil macro-aggregates (>0.25 mm) and the associated organic carbon content was elevated, damage to aggregates was reduced, and the organic carbon stability was enhanced. In general, the soil aggregate stability and organic carbon content of orchard soils were higher than for the farmland soils. Orchards appear to enhance the physical stability of aggregates with respect to soil organic carbon, contribute to soil organic carbon accumulation, and thus promote soil carbon sequestration.

7.
Sensors (Basel) ; 19(19)2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31569712

RESUMO

Automatic Identification System (AIS) data could support ship movement analysis, and maritime network construction and dynamic analysis. This study examines the global maritime network dynamics from multi-layers (bulk, container, and tanker) and multidimensional (e.g., point, link, and network) structure perspectives. A spatial-temporal framework is introduced to construct and analyze the global maritime transportation network dynamics by means of big trajectory data. Transport capacity and stability are exploited to infer spatial-temporal dynamics of system nodes and links. Maritime network structure changes and traffic flow dynamics grouping are then possible to extract. This enables the global maritime network between 2013 and 2016 to be investigated, and the differences between the countries along the 21st-century Maritime Silk Road and other countries, as well as the differences between before and after included by 21st-century Maritime Silk Road to be revealed. Study results indicate that certain countries, such as China, Singapore, Republic of Korea, Australia, and United Arab Emirates, build new corresponding shipping relationships with some ports of countries along the Silk Road and these new linkages carry significant traffic flow. The shipping dynamics exhibit interesting geographical and spatial variations. This study is meaningful to policy formulation, such as cooperation and reorientation among international ports, evaluating the adaptability of a changing traffic flow and navigation environment, and integration of the maritime economy and transportation systems.

8.
EBioMedicine ; 47: 365-372, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31447394

RESUMO

BACKGROUND: Islet autoantibodies (IAbs) are the most reliable biomarkers to assess risk of progression to clinical type 1 diabetes (T1D). There are four major biochemically defined IAbs currently used in clinical trials that are equally important for disease prediction. The current screening methods use a radio-binding assay (RBA) for single IAb measurement, which are laborious and inefficient for large-scale screening. More importantly, up to 40% of patients with T1D have other autoimmune conditions that can be identified through relevant autoantibody testing. Thus, there is a need to screen for T1D and other autoimmune diseases simultaneously. METHODS: Based on our well-established electrochemiluminescence (ECL) assay platform, we developed a multiplexed ECL assay that combines 7 individual autoantibody assays together in one single well to simultaneously screen T1D, and three other autoimmune diseases including celiac disease, autoimmune thyroid disease and autoimmune poly-glandular syndrome-1 (APS-1). The 7-Plex ECL assay was extensively validated against single antibody measurements including a standard RBA and single ECL assay. FINDINGS: The 7-Plex ECL assay was well correlated to each single ECL autoantibody assay and each RBA. INTERPRETATION: The multiplexed ECL assay provides high sensitivity and disease specificity, along with high throughput and a low cost for large-scale screenings of T1D and other relevant autoimmune diseases in the general population. FUND: JDRF grants 2-SRA-2015-51-Q-R, 2-SRA-2018-533-S-B, NIH grants DK32083 and DK32493. NSFC grants 81770777.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/imunologia , Ensaios de Triagem em Larga Escala , Adolescente , Adulto , Autoanticorpos/sangue , Doenças Autoimunes/sangue , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Feminino , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/normas , Humanos , Lactente , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
9.
ACS Appl Mater Interfaces ; 11(17): 15837-15844, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964258

RESUMO

n-Type organic/polymeric semiconductors with high electron mobilities are highly demanded for future flexible organic circuits. Except for developing a new conjugated backbone, recent studies show that side-chain engineering also plays an indispensable role in boosting the charge-transporting property. In this paper, we report a new polymer PNDI2T-DTD with a representative n-type naphthalene diimide (NDI)-bithiophene backbone for high-performance n-type flexible thin-film transistors through branching/linear side-chain engineering strategy. Serving as the flexible side chains, the linear/branching side-chain pattern is found to be effective in tuning the preaggregation behavior in solution and the packing ordering of polymeric chains, resulting in the improvement of thin-film crystallinity. The electron mobility of the thin film of PNDI2T-DTD on flexible substrates can reach 1.52 cm2 V-1 s-1, which is approximately five times higher than that of PNDI2T-DT with the same conjugated backbone and only branching alkyl chains.

10.
Nanoscale ; 11(8): 3583-3590, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30729970

RESUMO

We combine anisotropic wet etching and nanoskiving to create a novel three-dimensional (3D) nanoantenna for plasmonic nanofocusing, vertically aligned zig-zag nanogaps, constituted of nanogaps with defined angles. Instead of conventional lithography, we used the thickness of a self-assembled monolayer (SAM) to define nanogaps with high throughput, and anisotropic etching of Si V-grooves to naturally define ultra-sharp tips. Both nanogaps and sharp tips can synergistically squeeze the electro-magnetic (EM) field and excite 3D nanofocusing, enabling great potential applications in chemical sensing and plasmonic devices. The dependence of the EM field enhancement on structural features is systematically investigated and optimized. We found that the field enhancement and confinement are stronger at the tipped-nanogap compared to what standalone tips or nanogaps produce. The intensity of surface-enhanced Raman spectroscopy (SERS) recorded on the 70.5° tipped-nanogaps is 45 times higher than that recorded with linear nanogaps and 5 times higher than that recorded with tip-only nanowires, which is attributed to the integration of the tip and gap in plasmonic nanostructures. This proposed nanofabrication technique and the resulting structures equipped with a strongly enhanced EM field will promote broad applications for nanophotonics and surface-enhanced spectroscopy.

11.
Angew Chem Int Ed Engl ; 58(15): 5044-5048, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30793823

RESUMO

A goal for human society is to convert organic waste into valuable materials. Herein, 2-(methylthio)-bezothiazole (MTBT), an important organic waste in urban runoff, was catalytically converted into a series of organic semiconductors through carbon-sulfur bond activation. The efficient conversion of various substrates with different aromatic moieties and reacting functional groups (tin and boron) proved the generality of this novel diarylation Liebeskind-Srogl methodology. Moreover, the resulting organic semiconductors showed excellent performance in field effect transistors and cell imaging. This contribution presents an excellent example of converting organic waste into valuable materials and may open a new avenue to utilizing widely available aromatic thioethers.

12.
Methods Mol Biol ; 1901: 197-203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30539579

RESUMO

Appearance of autoantibodies to tissue transglutaminase (TGA) is the most reliable biomarker to identify celiac disease autoimmunity. A nonradioactive assay of determination of TGA was newly developed using electrochemiluminescence (ECL) technology. This ECL assay has been demonstrated to be more sensitive than current standard radio-binding assay (RBA) in detecting TGA and can detect TGA earlier among high-risk young children followed from birth.


Assuntos
Autoanticorpos/análise , Medições Luminescentes/métodos , Transglutaminases/imunologia , Bioensaio , Biotina/metabolismo , Humanos , Controle de Qualidade , Padrões de Referência , Soro/metabolismo
13.
Cell Physiol Biochem ; 50(6): 2365-2389, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30423573

RESUMO

BACKGROUND/AIMS: The etiology of asthma, which is a complicated disorder with various symptoms, including wheezing, coughing, and airflow obstruction, remains poorly understood. In addition, the effects of microRNAs (miRs) have not been explored. This study explored the effect of microRNA-200a (miR-200a) on airway smooth muscle cells (ASMCs) and airway remodeling in asthmatic mice. Furthermore, we speculated that miR-200a achieves its effect by targeting FOXC1 via the PI3K/AKT signaling pathway based on differentially expressed gene screening, target miR predictions and a bioinformatics analysis. METHODS: Eighty mice were assigned to a saline group or an ovalbumin (OVA) group, and the OVA group was transfected with a series of inhibitors, activators, and siRNAs to test the established mouse model. Airway reactivity and the ratio of eosinophils (EOSs) to leukocytes were detected. An ELISA was adopted to measure the levels of interleukin (IL)-4, IL-6, IL-8, tumor necrosis factor (TNF)-α, and immunoglobulin E (IgE). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to determine the expression of FOXC1, PI3K, AKT, NF-κB, cyclin D1, TGF-ß1 and p-AKT in ASMCs. Finally, CCK-8 assays were performed to detect cell proliferation and flow cytometry to detect apoptosis and cell cycle entry. RESULTS: The bioinformatics analysis indicated that miR-200a mediated the PI3K/AKT signaling pathway by targeting FOXC1. In addition, mouse models of asthma were established. An elevated expression of miR-200a, a decreased mRNA and protein expression of FOXC1, PI3K, AKT, NF-κB, cyclin D1 and TGF-ß1, a decreased expression of p-AKT, suppressed cell proliferation, accelerated apoptosis, and an increased number of cells at the G0/G1 phase were observed following the upregulation of miR-200a and downregulation of FOXC1. CONCLUSION: The overexpression of miR-200a may downregulate FOXC1, thereby inhibiting the activation of the PI3K/AKT signaling pathway and ultimately suppressing ASMC proliferation and airway remodeling in asthmatic mice. This evidence supports the potential that miR-200a represents a new approach to treating asthma.


Assuntos
Remodelação das Vias Aéreas , Asma/etiologia , Fatores de Transcrição Forkhead/metabolismo , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Antagomirs/metabolismo , Asma/imunologia , Asma/metabolismo , Proliferação de Células , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/antagonistas & inibidores , Fatores de Transcrição Forkhead/genética , Pontos de Checagem da Fase G1 do Ciclo Celular , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Ovalbumina/imunologia , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
14.
J Clin Endocrinol Metab ; 103(10): 3589-3592, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30124874

RESUMO

Context: Immune checkpoint inhibitors, including monoclonal antibodies directed against programmed cell death protein 1 (PD-1) and its ligand, have emerged as beneficial cancer immunotherapies. These therapies are known to cause immune-related side effects; however, their role in patients with a preexisting autoimmune disease is not clear. Case Description: We describe two cases of anti-PD-1 immune-related adverse events. A 52-year-old male with longstanding type 1 diabetes (T1D), long-term stable kidney transplant, and hypothyroidism received two separate anti-PD-1 monoclonal antibodies for metastatic melanoma. The patient developed acute kidney graft rejection requiring hemodialysis and worsening of autoimmune hypothyroidism 3 weeks after starting treatment. He continued anti-PD-1 treatments and remained on hemodialysis and increased levothyroxine dosage. The second case is a 62-year-old male with no previous history of diabetes who received anti-PD-1 treatment and developed severe diabetic ketoacidosis (DKA) 5 days following the start of therapy. Further laboratory testing revealed high titer antibodies directed against glutamic acid decarboxylase. These antibodies, which were of the IgG isotype and involved in memory immune responses, were likely present before anti-PD-1 treatment. He also had human leukocyte antigen genes that confer T1D genetic risk. Despite normal pretreatment blood glucose levels and HbA1c, the patient requires permanent exogenous insulin treatment. Conclusion: Patients with preexisting endocrine autoimmunity may have more frequent and severe immune-related side effects with anti-PD-1 treatment. Given the morbidity and mortality associated with solid organ transplant rejection and DKA, clinicians caring for patients receiving these state-of-the-art therapies need to be aware of the potential adverse events.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Diabetes Mellitus Tipo 1/induzido quimicamente , Rejeição de Enxerto/etiologia , Melanoma/tratamento farmacológico , Receptor de Morte Celular Programada 1/imunologia , Antineoplásicos Imunológicos/efeitos adversos , Autoimunidade/efeitos dos fármacos , Diabetes Mellitus Tipo 1/fisiopatologia , Humanos , Imunoterapia/efeitos adversos , Transplante de Rim/efeitos adversos , Masculino , Melanoma/imunologia , Melanoma/patologia , Pessoa de Meia-Idade , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/secundário
15.
J Vis Exp ; (133)2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29630056

RESUMO

Pinpointing islet autoantibodies associated with type 1 diabetes (T1D) leads the way to project and deter this disease in the general population. A novel ECL assay is a nonradioactive fluid phase assay for islet autoantibodies with higher sensitivity and specificity than the current 'gold' standard radio-binding assay (RBA). ECL assays can more precisely define the onset of presymptomatic T1D by distinguishing the high-risk, high-affinity autoantibodies from the low-risk, low-affinity autoantibodies generated in RBAs, and conventional enzyme-linked immunosorbent assays (ELISA). The antigen protein used in this ECL assay is labeled with Sulfo-tag and Biotin, respectively. Each ECL autoantibody assay that uses a particular antigen protein needs an optimization step before it can be used for laboratory application. This step is especially vital in determining the requirements for serum acid treatments, concentrations, and ratios of the two different antigens labeled with Sulfo-tag and Biotin. To perform the assay, serum samples are mixed with Sulfo-tag-conjugated and biotinylated capture antigen protein in phosphate buffered solution (PBS), containing 5% Bovine Serum Albumin (BSA). Afterwards, the samples are incubated overnight at 4 °C. The same day, a streptavidin-coated plate is prepared with blocker buffer and incubated overnight at 4 °C. On the second day, wash the streptavidin plate and transfer the serum-antigen mixture onto the plate. Place the plate on the plate shaker, set it at low speed, and incubate at room temperature for 1 h. Subsequently, the plate is washed again, and reader buffer is added. The plate is then counted on the plate reader machine. The results are conveyed through an index, which is generated from internal standard positive and negative control serum samples.


Assuntos
Autoanticorpos/sangue , Técnicas Eletroquímicas/métodos , Ilhotas Pancreáticas/diagnóstico por imagem , Medições Luminescentes/métodos , Humanos
16.
J Am Chem Soc ; 139(49): 17735-17738, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29160068

RESUMO

We report a regioregular bis-pyridal[2,1,3]-thiadiazole (BPT) acceptor strategy to construct the first ambipolar pyridal[2,1,3]thiadiazole-based semiconducting polymer (PBPTV). The use of BPT unit enables PBPTV to achieve high electron affinity, low LUMO level, and extended π-conjugation. All these factors provide PBPTV with encouraging hole and electron mobilities up to 6.87 and 8.49 cm2 V-1 s-1, respectively. Our work demonstrates that the BPT unit is a promising building block for designing high-performance electron-transporting semiconductors in organic electronics.

17.
ACS Appl Mater Interfaces ; 9(46): 40549-40555, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29047276

RESUMO

The exploration of novel electron-deficient building blocks is a key task for developing high-performance polymer semiconductors in organic thin-film transistors. In view of the situation of the lack of strong electron-deficient building blocks, we designed two novel π-extended isoindigo-based electron-deficient building blocks, IVI and F4IVI. Owing to the strong electron-deficient nature and the extended π-conjugated system of the two acceptor units, their copolymers, PIVI2T and PF4IVI2T, containing 2,2'-bithiophene donor units, are endowed with deep-lying highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) energy levels and strong intermolecular interactions. In comparison to PIVI2T, the fluorinated PF4IVI2T exhibits stronger intra- and intermolecular interactions, lower HOMO/LUMO energy levels up to -5.74/-4.17 eV, and more ordered molecular packing with a smaller π-π stacking distance of up to 3.53 Å, resulting in an excellent ambipolar transporting behavior and a promising application in logic circuits for PF4IVI2T in ambient with hole and electron mobilities of up to 1.03 and 1.82 cm2 V-1 s-1, respectively. The results reveal that F4IVI is a promising and strong electron-deficient building unit to construct high-performance semiconducting polymers, which provides an insight into the structure-property relationships for the exploration and molecular engineering of excellent electron-deficient building blocks in the field of organic electronics.

18.
PLoS One ; 12(9): e0185705, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28957428

RESUMO

Water deficit significantly limits dryland rainfed fruit production, so increasing water conservation is crucial for improving fruit productivity in arid and semiarid areas. In this study, we tested two treatments in an apple orchard: 1) PC treatment comprising black plastic mulch (BPM) (in-row) with weed control (inter-row); 2) and PGC treatment comprising BPM (in-row) combined with a summer cover crop (inter-row) of rape (Brassica campestris L.), which was sown in mid-June and was living from July to September. Under PGC, the inter-row soil water storage increased by 17.9% and 11.5% compared with PC after the harvest in 2013 and 2014, respectively, but there was no significant increase in 2015. The evapotranspiration (ET) from the inter-row areas during the cover crop period was lower under PGC than PC in 2013 (19.6%), 2014 (11.3%), and 2015 (13.3%). However, the differences in the total ET from the inter-row areas between the two treatments were not obvious, and the total ET from in-row areas was higher under PGC than PC due to the increased water uptake by apple trees under PGC. The apple yield, water use efficiency during the cover crop period (WUEg) and total water use efficiency (WUE) fluctuated during the experimental years. Compared with PC, the apple yield increased by 14.1%, 18.8%, and 26.7% under PGC in 2013, 2014, and 2015, respectively. In addition, the WUEg was 26.4%, 24.7%, and 32.7% higher under PGC compared with PC in 2013, 2014, and 2015, respectively. Thus, the WUE under PGC was 13.8% and 11.7% higher than that under PC in 2013 and 2014, respectively, but the difference was not significant in 2015 (p = 0.0527). Thus, BPM combined with a summer cover crop is recommended for decreasing the summer ET and promoting apple production in rainfed dryland areas where the rainy season is usually the hot season.


Assuntos
Produtos Agrícolas , Malus , Plásticos , Chuva , Estações do Ano , Solo , Temperatura Ambiente
19.
Adv Mater ; 29(36)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28736833

RESUMO

So far, most of the reported high-mobility conjugated polymers are p-type semiconductors. By contrast, the advances in high-mobility ambipolar polymers fall greatly behind those of p-type counterparts. Instead of unipolar p-type and n-type materials, ambipolar polymers, especially balanced ambipolar polymers, are potentially serviceable for easy-fabrication and low-cost complementary metal-oxide-semiconductor circuits. Therefore, it is a critical issue to develop high-mobility ambipolar polymers. Here, three isoindigo-based polymers, PIID-2FBT, P1FIID-2FBT, and P2FIID-2FBT are developed for high-performance ambipolar organic field-effect transistors. After the incorporation of fluorine atoms, the polymers exhibit enhanced coplanarity, lower energy levels, higher crystallinity, and thus increased µe . P2FIID-2FBT exhibits n-type dominant performance with a µe of 9.70 cm2 V-1 s-1 . Moreover, P1FIID-2FBT exhibits a highly balanced µh and µe of 6.41 and 6.76 cm2 V-1 s-1 , respectively, which are among the highest values for balanced ambipolar polymers. Moreover, a concept "effective mass" is introduced to further study the reasons for the high performance of the polymers. All the polymers have small effective masses, indicating good intramolecular charge transport. The results demonstrate that high-mobility ambipolar semiconductors can be obtained by designing polymers with fine-tuned energy levels, small effective masses, and high crystallinity.

20.
J Biol Chem ; 292(37): 15489-15500, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28743741

RESUMO

DNA replication greatly enhances expression of the herpes simplex virus 1 (HSV-1) γ2 late genes by still unknown mechanisms. Here, we demonstrate that 5,6-dichloro-1-ß-d-ribofuranosylbenzimidazole (DRB), an inhibitor of CDK9, suppresses expression of γ2 late genes with an IC50 of 5 µm, which is at least 10 times lower than the IC50 value required for inhibition of expression of early genes. The effect of DRB could not be explained by inhibition of DNA replication per se or loading of RNA polymerase II to late promoters and subsequent reduction of transcription. Instead, DRB reduces accumulation of γ2 late mRNA in the cytoplasm. In addition, we show that siRNA-mediated knockdown of the transcription factor SPT5, but not NELF-E, also gives rise to a specific inhibition of HSV-1 late gene expression. Finally, addition of DRB reduces co-immunoprecipitation of ICP27 using an anti-SPT5 antibody. Our results suggest that efficient expression of replication-dependent γ2 late genes is, at least in part, regulated by CDK9 dependent co- and/or post-transcriptional events involving SPT5 and ICP27.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Quinase 9 Dependente de Ciclina/metabolismo , Replicação do DNA , Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Replicação Viral , Substituição de Aminoácidos , Antivirais/farmacologia , Linhagem Celular , Imunoprecipitação da Cromatina , Proteínas Cromossômicas não Histona/antagonistas & inibidores , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/genética , Biologia Computacional , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/genética , Replicação do DNA/efeitos dos fármacos , Diclororribofuranosilbenzimidazol/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/crescimento & desenvolvimento , Humanos , Proteínas Imediatamente Precoces/química , Proteínas Imediatamente Precoces/genética , Imunoprecipitação , Mutação , Inibidores da Síntese de Ácido Nucleico/farmacologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/antagonistas & inibidores , Fatores de Elongação da Transcrição/química , Fatores de Elongação da Transcrição/genética , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
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