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1.
Am J Surg Pathol ; 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31567190

RESUMO

The pattern-based classification system of endocervical adenocarcinoma correlates with nodal metastasis and clinical outcomes, but its application in biopsies is challenging. The aim of this study was the correlation of additional histologic features with patterns of invasion as well as prognosis. A total of 103 specimens from 71 cervical adenocarcinoma cases were studied. Among the 71 cases, all had resection specimens including hysterectomy, cold knife cone excision or loop electrosurgical excision procedure excision, and 32 of these had prior cervical biopsies. We applied the pattern-based classification system to all the specimens and evaluated histopathologic features microscopically. Findings in biopsies were compared with their corresponding resections and correlated with nodal status and disease stage. In 71 resection specimens, pattern A was present in 10 (14.1%), pattern B in 12 (16.9%), and pattern C in 49 (69%) cases. Of the 32 cervical biopsies, pattern of invasion could be classified in only 16 (50%) cases, including 1 (6%) with pattern A, 4 (25%) with pattern B, and 11 (69%) with pattern C. Of the 32 cervical biopsies, 30 could be evaluated for intraluminal necrotic/tumor debris and/or grade 3 nuclei, which correlated with pattern C as well as with lymph node metastasis in the subsequent staging specimens. No tumor with patterns A or B had intraluminal necrotic/tumor debris or grade 3 nuclei in either biopsy or resection specimens. Therefore, intraluminal necrotic/tumor debris and grade 3 nuclei are highly predictive histologic features for cervical adenocarcinomas with pattern C invasion and nodal metastasis.

2.
J Mater Chem B ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31593203

RESUMO

As oxidative stress is involved with inflammation and neovascularization, blocking oxidative stress may be beneficial for reducing inflammation. To investigate the potential use of cerium oxide nanoparticles (CeNPs) in treating neovascularization-related ophthalmic diseases, various CeNP samples were synthesized, and the sample with the best antioxidant efficacy was used in a rat model of inflammation-associated corneal neovascularization. This synthesized cerium oxide showed good biocompatibility and was capable of mediating a decrease in the expression levels of inflammatory factors via antioxidative stress. Additionally, in vitro tests showed that the Ce3+/Ce4+ ratio of the CeNPs directly affected the antioxidative activity, with higher ratios achieving better efficacy. The anti-inflammatory efficacy of the functional CeNPs was examined both in vitro and in vivo. Slit-lamp biomicroscopy and histological analysis revealed the gradual development of corneal neovascularization, suggesting that inflammation and neovascularization could be controlled by reducing the level of oxidative stress. CeNP-induced antioxidation could serve as a new strategy in the development of long-acting functional agents for treating ophthalmic diseases.

3.
Adv Mater ; : e1903559, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566819

RESUMO

Large-bandgap perovskites offer a route to improve the efficiency of energy capture in photovoltaics when employed in the front cell of perovskite-silicon tandems. Implementing perovskites as the front cell requires an inverted (p-i-n) architecture; this architecture is particularly effective at harnessing high-energy photons and is compatible with ionic-dopant-free transport layers. Here, a power conversion efficiency of 21.6% is reported, the highest among inverted perovskite solar cells (PSCs). Only by introducing a secondary amine into the perovskite structure to form MA1- x DMAx PbI3 (MA is methylamine and DMA is dimethylamine) are defect density and carrier recombination suppressed to enable record performance. It is also found that the controlled inclusion of DMA increases the hydrophobicity and stability of films in ambient operating conditions: encapsulated devices maintain over 80% of their efficiency following 800 h of operation at the maximum power point, 30 times longer than reported in the best prior inverted PSCs. The unencapsulated devices show record operational stability in ambient air among PSCs.

4.
J Steroid Biochem Mol Biol ; : 105491, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31586638

RESUMO

Vitamin D is very important for children's health. Previous studies have shown that vitamin D deficiency leads to a series of diseases in adults. However, pediatricians are mostly aware of rickets caused by vitamin D deficiency in children and poorly aware of other symptoms. This study aimed to retrospectively analyze the different clinical features of vitamin D deficiency to enhance identification by pediatricians, thus minimizing misdiagnosis. In this study, we retrospectively analyzed the clinical features of vitamin D deficiency in 268 children aged 0-14 years from June 2016 to May 2018 in the Third Affiliated Hospital of Zhengzhou University. Serum 25-hydroxy vitamin D [25(OH)D] levels were determined using the chemiluminescence method. Of the 268 cases, 101 cases showed movement disorder (37.7 %) and 167 nervous system abnormalities (62.3%). Among all cases, 6 were misdiagnosed as febrile seizures (2.23%), 5 as epilepsy (1.86 %), 2 as Tourette syndrome (0.74%), and 2 as developmental retardation (0.74%). There were significant differences in patients with clinical characteristics of movement disorder and nervous system abnormalities partly between Pre-and post-vitamin D treatment. This analysis revealed that vitamin D deficiency occurs not only in children but also in adolescents, with diverse clinical features. Therefore, pediatricians should pay more attention to clinical different signs and symptoms, and future studies should be conducted to confirm the mechanisms of these processes.

5.
Carcinogenesis ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31587040

RESUMO

Previous research suggests that Far Upstream-element Binding Protein 1 (FUBP1)plays an important role in various tumors including Hepatocellular carcinoma (HCC). However, the role of FUBP1 in liver cancer remains controversial, and the regulatory pathway by FUBP1 awaits to be determined. This study aims to identify the role of FUBP1 in hepatocellular carcinoma progression. Our result shows that high level of FUBP1 expression in HCC predicts poor prognosis after surgery. Overexpression of FUBP1 promotes HCC proliferation, invasion and metastasis by activating Transforming Growth Gactor-ß(TGF-ß)/Smad pathway and enhancing Epithelial-Mesenchymal Transition (EMT) in vitro and in vivo. Inhibitor of Thrombospondin-1 (LSKL)could inhibit HCC proliferation and invasion in vitro and in vivo by blocking the activation of TGF-ß/Smad pathway mediated by Thrombospondin-1 (THBS1). Our study identified the critical role of FUBP1-THBS1-TGF-ß signaling axis in HCC and provides potentially new therapeutic modalities in HCC.

6.
Small ; : e1903880, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588682

RESUMO

Endophthalmitis, derived from the infections of pathogens, is a common complication during the use of ophthalmology-related biomaterials and after ophthalmic surgery. Herein, aiming at efficient photodynamic therapy (PDT) of bacterial infections and biofilm eradication of endophthalmitis, a pH-responsive zeolitic imidazolate framework-8-polyacrylic acid (ZIF-8-PAA) material is constructed for bacterial infection-targeted delivery of ammonium methylbenzene blue (MB), a broad-spectrum photosensitizer antibacterial agent. Polyacrylic acid (PAA) is incorporated into the system to achieve higher pH responsiveness and better drug loading capacity. MB-loaded ZIF-8-PAA nanoparticles are modified with AgNO3 /dopamine for in situ reduction of AgNO3 to silver nanoparticles (AgNPs), followed by a secondary modification with vancomycin/NH2 -polyethylene glycol (Van/NH2 -PEG), leading to the formation of a composite nanomaterial, ZIF-8-PAA-MB@AgNPs@Van-PEG. Dynamic light scattering, transmission electron microscopy, and UV-vis spectral analysis are used to explore the nanoparticles synthesis, drug loading and release, and related material properties. In terms of biological performance, in vitro antibacterial studies against three kinds of bacteria, i.e., Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus, suggest an obvious superiority of PDT/AgNPs to any single strategy. Both in vitro retinal pigment epithelium cellular biocompatibility experiments and in vivo mice endophthalmitis models verify the biocompatibility and antibacterial function of the composite nanomaterials.

7.
Drug Des Devel Ther ; 13: 3391-3404, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576113

RESUMO

Purpose: It has been reported that approximately 40% of ALI (acute lung injury) incidence resulted from sepsis. Paclitaxel, as a classic anti-cancer drug, plays an important role in the regulation of inflammation. However, we do not know whether it has a protective effect against CLP (cecal ligation and puncture)-induced septic ALI. Our study aims to illuminate the mitigative effects of paclitaxel on sepsis-induced ALI and its relevant mechanisms. Materials and methods: The survival rates and organ injuries were used to evaluate the effects of paclitaxel on CLP mice. The levels of inflammatory cytokines were tested by ELISA. MUC1 siRNA pre-treatment was used to knockdown MUC1 expression in vitro. GO203 was used to inhibit the homodimerization of MUC1-C in vivo. The expression levels of MUC1, TLR 4 and p-NF-κB/p65 were detected by Western blot. Results: Our results showed that paclitaxel improved the survival rates and ameliorated organ injuries especially lung injury in CLP-induced septic mice. These were accompanied by reduced inflammatory cytokines in sera and BALF (bronchoalveolar lavage fluid). We also found paclitaxel could attenuate TLR 4-NF-κB/p65 activation both in lung tissues of septic mice and LPS-stimulated lung type II epithelial cell line A549. At the upstream level, paclitaxel-upregulated expression levels of MUC1 in both in vivo and in vitro experiments. The inhibitory effects of paclitaxel on TLR 4-NF-κB/p65 activation were reversed in lung tissues of septic mice pre-treated with MUC1 inhibitor and in MUC1-knockdown A549 cells. Protection of paclitaxel on sepsis-induced ALI and decrease of inflammatory cytokines were also abolished by inhibition of MUC1. Conclusion: Collectively, these results indicated paclitaxel could significantly alleviate acute lung injury in CLP-induced septic mice and LPS-stimulated lung type II epithelial cell line A549 by activating MUC1 and suppressing TLR-4/NF-κB pathway.

8.
Ann Transplant ; 24: 553-568, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31582715

RESUMO

BACKGROUND Interstitial fibrosis and tubular atrophy (IF/TA) have been recognized as crucial factors contributing to graft loss resulting from chronic renal allograft injuries. Recent studies have indicated a significant association between the progression of organ fibrosis and single nucleotide polymorphisms (SNPs) found on certain genes. Our research sought to understand these potential associations and detect the potential impact of SNPs on ubiquitin-related genes related to allograft fibrosis in kidney transplant recipients. MATERIAL AND METHODS There were 200 patients enrolled in this study, from which samples were extracted for total DNA. Targeted next-generation sequencing was used to detect SNPs on 9 genes (FBXL21, PIAS1/2, SUMO1/2/3/4, UBE2D1, and UBE2I). Minor allele frequency (MAF) and Hardy-Weinberg equilibrium (HWE) tests were used and followed by linkage disequilibrium analysis. General linear models (GLM) were used to identify significant confounding factors. Finally, multiple inheritance models and haplotype analyses were conducted to explore associations between SNPs and the degree of the severity of renal allograft fibrosis. RESULTS In total, 144 SNPs were identified in targeted sequencing. After filtering based on results from MAF and HWE tests, 15 tagger SNPs were selected for further analyses of associations. GLMs indicated that the administration of sirolimus significantly contributed to the degree of severity of allograft fibrosis (P=0.011). After adjusting for confounding factors and applying a Bonferroni correction, multiple inheritance model analyses indicated that the recessive model of rs644731 of the PIAS2 gene was significantly correlated with the occurrence of IF/TA (P=0.01). Furthermore, single-locus based analysis of rs644731 did not indicate that it had a positive influence on IF/TA in a degree-dependent manner. Finally, linkage disequilibrium analysis revealed 3 haplotypes all lacking significant correlation with respect to the IF/TA experimental cohort. CONCLUSIONS We are the first to reveal that mutations of rs644731 in the PIAS2 gene were significantly correlated with the progression of IF/TA in kidney transplant recipients.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31596062

RESUMO

In this study we synthesized four A-D-A type hole transporting materials (HTMs) of SY1~SY4 for an HTMs/interfacial layer with carbazole as the core moiety and ester/amide as the acceptor unit. These HTMs contain 4-hexyloxyphenyl substituents on the carbazole N atom, with extended π-conjugation achieved through phenylene and thiophene units at the 3,6-positions of the carbazole. When using amide-based HTMs SY2 as a dopant-free HTM in a p-i-n perovskite solar cell (PSC), we achieved a power conversion efficiency (PCE) of 13.59% under AM 1.5G conditions (100 mW cm-2); this PCE was comparable with that obtained when using PEDOT:PSS as the HTM (12.33%). Amide-based SY2 and SY4 HTMs showed a larger perovskite grain than SY1 and SY3, due to the passivation of traps/defects at the grain boundaries and stronger interaction with the perovskite layer. In further investigation, we demonstrated highly efficient and stable PSCs when using the dopant-free p-i-n device structure ITO/NiOx/interfacial layer (SY-HTMs)/perovskite/PC61BM/BCP/Ag. The interfacial layer improved the PCEs and large grain size (micrometer scale) of the perovskite layer due to defect passivation and interface modification; the amide group exhibited a Lewis base adduct property coordinated to Ni and Pb ions in the NiOx and perovskite, bifacial defect passivation and reduced the grain boundaries to improve the crystallinity of the perovskite. The amide-based SY2 exhibited the stronger interaction with the perovskite layer than that of ester-based SY1, which is related to the observations in X-ray absorption near edge structure (XANES). The best performance of the NiOx/SY2 device was characterized by a short-circuit current density (Jsc) of 21.76 mA cm-2, an open-circuit voltage (Voc) of 1.102 V, and a fill factor (FF) of 79.1%, corresponding to an overall PCE of 18.96%. The stability test of the PCE of the NiOx/SY2 PSC device PCE showed a decay of only 5.01% after 168 h; it retained 92.01% of its original PCE after 1000 h in Ar atmosphere. Time-resolved photoluminescence (TRPL) spectra of the perovskite films suggested that the hole extraction capabilities of the NiOx/SY-HTMs were better than that of the bare NiOx. The superior film morphologies of the NiOx/SY-HTMs were responsible for the performances of their devices being comparable with those of bare NiOx-based PSCs. The photophysical properties of the HTMs were analyzed through time-dependent density functional theory with the B3LYP functional.

10.
Vet Immunol Immunopathol ; 218: 109953, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31590073

RESUMO

Tembusu virus (TMUV) is a contagious pathogen of waterfowl including ducks and geese, which causes symptoms of high fever, loss of appetite and reduced egg production. The development of an effective vaccine is important for the prevention and control of the disease. We evaluated a DNA vaccine based on a recombinant pre-membrane (prM) and envelope (E) protein, using CpG oligodeoxynucleotide (ODN) as an adjuvanted, and tested it for protection efficacy. BHK21 cells were transfected with the recombinant plasmid pVAX1-prM/E-CpG, and the antigenicity of the expressed protein was detected using an indirect immunofluorescence assay (IFA) and western blot assay. One-day-old ducklings were intramuscularly injected with 200 µg doses of pVAX1-prM/E-CpG or pVAX1-CpG, or PBS at ten day intervals. The neutralizing antibodies and cell-mediated immune responses elicited by the DNA vaccine were detected using serum neutralization tests (SNTs) and ELISAs. At 20 days old, the ducks were challenged with 103EID50 doses of TMUV SD/02 strain and observed for 15 days post challenge. After the second DNA vaccination and during the monitoring period, the levels of TMUV neutralizing antibodies increased in the pVAX1-prM/E-CpG vaccinated ducks. Vaccination with pVAX1-prM/E-CpG resulted in 100.0% protection of the ducks, whereas approximately 40% of ducks vaccinated with pVAX-CpG or PBS manifested clinical symptoms. Expressions of IFN-γ and IL-6 in the pVAX1-prM/E-CpG group were significantly increased (p <  0.01) compared with the control groups during the entire experimental period. The results revealed that a vaccine co-expressing prM and E, and using a CpG-ODN motif as an adjuvant, could elicit effective neutralizing antibody titers and provide efficient protection to ducks against TMUV infection.

11.
Exp Cell Res ; 384(1): 111606, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493386

RESUMO

Pancreatic stellate cells (PSCs) have been recognized as key mediators of pancreatic fibrosis, a characteristic feature of chronic pancreatitis (CP). As a cullin-based E3 ubiquitin ligase, speckle-type POZ protein (SPOP) has been identified to participate in tumorigenesis and organ development. However, its biological role in CP remains unknown. Therefore, this study sought to investigate the changed expression of SPOP in CP and to examine the effect on mice PSCs activation of SPOP. We found that SPOP was downregulated in the pancreatic tissues of cerulein-induced CP mice. siRNA-mediated knockdown of SPOP led to significant promotion in primary PSCs activity by activating the nuclear factor-kappaB (NF-κB)/interleukin-6 (IL-6) signaling pathway. In addition, we examined the effects of Fas-associated death domain (FADD), a proven SPOP substrate that activates NF-κB, on the regulation of PSCs activation. We found that FADD was downregulated by SPOP via interaction-mediated degradation, and was upregulated during PSCs activation. The promotion of PSCs activation in knocking down SPOP with siSPOP-1 were counteracted by knocking down FADD. The results suggest that the SPOP-induced inhibition of PSCs activation partially depended on FADD. These results highlight the importance of SPOP in CP and provide a potential target for therapeutic intervention.

12.
Bioinformatics ; 35(14): i284-i294, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31510699

RESUMO

MOTIVATION: Alternative splicing generates multiple isoforms from a single gene, greatly increasing the functional diversity of a genome. Although gene functions have been well studied, little is known about the specific functions of isoforms, making accurate prediction of isoform functions highly desirable. However, the existing approaches to predicting isoform functions are far from satisfactory due to at least two reasons: (i) unlike genes, isoform-level functional annotations are scarce. (ii) The information of isoform functions is concealed in various types of data including isoform sequences, co-expression relationship among isoforms, etc. RESULTS: In this study, we present a novel approach, DIFFUSE (Deep learning-based prediction of IsoForm FUnctions from Sequences and Expression), to predict isoform functions. To integrate various types of data, our approach adopts a hybrid framework by first using a deep neural network (DNN) to predict the functions of isoforms from their genomic sequences and then refining the prediction using a conditional random field (CRF) based on co-expression relationship. To overcome the lack of isoform-level ground truth labels, we further propose an iterative semi-supervised learning algorithm to train both the DNN and CRF together. Our extensive computational experiments demonstrate that DIFFUSE could effectively predict the functions of isoforms and genes. It achieves an average area under the receiver operating characteristics curve of 0.840 and area under the precision-recall curve of 0.581 over 4184 GO functional categories, which are significantly higher than the state-of-the-art methods. We further validate the prediction results by analyzing the correlation between functional similarity, sequence similarity, expression similarity and structural similarity, as well as the consistency between the predicted functions and some well-studied functional features of isoform sequences. AVAILABILITY AND IMPLEMENTATION: https://github.com/haochenucr/DIFFUSE. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

13.
World Neurosurg ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31520754

RESUMO

OBJECTIVE: To first explore the safety and efficacy of H2O2 in controlling blood loss and SSI after multi-segmental lumbar spine surgery. METHODS: 2626 patients who underwent multi-segmental lumbar spinal surgery between January 2015 and January 2018 were included in this study. According to whether H2O2 irrigation was applied, they were divided into control group (1345 patients) and experimental group (1281 patients). Besides the demographic parameters, the laboratory examination results and surgery related information such as operative time, numbers of operated levels, intraoperative blood loss, postoperative drainage, postoperative SSI, extubation time and perioperative complications were recorded. RESULTS: No significant differences were seen regarding demographic parameters, laboratory examination results, comorbidities and surgical related information. The extubation time and postoperative drain collection were lower in the experimental group (3.6±0.5 days vs. 4.1±0.6, p=0.402; 251.8±67.5 vs. 291.8±71.3, p=0.013). In the control group, the rate of SSI was 2.4% (32/1345), including 17 superficial wound infections and 15 deep wound infections. In the experimental group, the SSI rate was 1.4% (18/1281), including 15 patients with superficial wound infection and 3 with deep wound infection. Staphylococcus aureus was the most common organism, especially in the experimental group (66.7% vs. 50%). There was no significant difference between both groups in the perioperative complications such as hematencephalon, DVT, PE, and MI (p>0.05, respectively). Pneumocephalus was not observed in either group. CONCLUSION: The application of H2O2 in PLIF can reduce the blood loss and SSI after surgery, which is quite beneficial for controlling the increasing number of vancomycin-resistant bacteria.

14.
IEEE Trans Cybern ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31484154

RESUMO

Histopathology image analysis serves as the gold standard for cancer diagnosis. Efficient and precise diagnosis is quite critical for the subsequent therapeutic treatment of patients. So far, computer-aided diagnosis has not been widely applied in pathological field yet as currently well-addressed tasks are only the tip of the iceberg. Whole slide image (WSI) classification is a quite challenging problem. First, the scarcity of annotations heavily impedes the pace of developing effective approaches. Pixelwise delineated annotations on WSIs are time consuming and tedious, which poses difficulties in building a large-scale training dataset. In addition, a variety of heterogeneous patterns of tumor existing in high magnification field are actually the major obstacle. Furthermore, a gigapixel scale WSI cannot be directly analyzed due to the immeasurable computational cost. How to design the weakly supervised learning methods to maximize the use of available WSI-level labels that can be readily obtained in clinical practice is quite appealing. To overcome these challenges, we present a weakly supervised approach in this article for fast and effective classification on the whole slide lung cancer images. Our method first takes advantage of a patch-based fully convolutional network (FCN) to retrieve discriminative blocks and provides representative deep features with high efficiency. Then, different context-aware block selection and feature aggregation strategies are explored to generate globally holistic WSI descriptor which is ultimately fed into a random forest (RF) classifier for the image-level prediction. To the best of our knowledge, this is the first study to exploit the potential of image-level labels along with some coarse annotations for weakly supervised learning. A large-scale lung cancer WSI dataset is constructed in this article for evaluation, which validates the effectiveness and feasibility of the proposed method. Extensive experiments demonstrate the superior performance of our method that surpasses the state-of-the-art approaches by a significant margin with an accuracy of 97.3% . In addition, our method also achieves the best performance on the public lung cancer WSIs dataset from The Cancer Genome Atlas (TCGA). We highlight that a small number of coarse annotations can contribute to further accuracy improvement. We believe that weakly supervised learning methods have great potential to assist pathologists in histology image diagnosis in the near future.

15.
Int J Mol Sci ; 20(18)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540278

RESUMO

The two-line hybrid rice is an important factor of a global crop, but its fertility transition mechanism is unclear. Here, a comparative proteomics and transcriptomics analysis was completed on the two-line hybrid rice line Wuxiang S (WXS) to explore its molecular mechanism and protein regulation during fertility transition. A total of 340 differentially abundant proteins (DAPs) were identified using iTRAQ between the pollen mother cell formation stage (P2) and the meiosis stage (P3). There were 3541 and 4247 differentially expressed genes (DEGs) in P2 and P3 between WXS (Sterile, S)-WXS(S) and WXS (Fertile, F)-WXS(F), respectively, of which 92 and 71 DEGs had corresponding DAPs. Among the DAPs and DEGs, 65 (SP2 vs. FP2) and 55 (SP3 vs. FP3) corresponding DEGs and DAPs (cor-DEGs-DAPs) showed the same expression trend, indicating the cor-DEGs-DAPs genes might play vital roles in WXS fertility transition. Further analysis indicated that cor-DEGs-DAPs proteins were related to energy metabolism-related proteins in anther development and were accompanied by the activation of the stress response pathway and modifications to the cell wall, which ultimately affected the fertility transition of the PTGMS rice line WXS.

16.
Sensors (Basel) ; 19(18)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540328

RESUMO

Advances in nanotechnology have provided approaches for the fabrication of new composite materials for sensing. Flexible sensors can make up for the shortcomings of traditional strain sensors in monitoring the surface strain and cracks of concrete structures. Using reduced graphene oxide (RGO) as a conductive filler, cellulose nanofiber (CNF) as a dispersant and structural skeleton, and waterborne epoxy (WEP) as a polymer matrix, a flexible composite material with piezoresistive effect was prepared by the solution blending and solvent evaporation method. The mechanical, electrical, and electromechanical properties of the composite were investigated. The results show that CNF can significantly improve the dispersion of RGO in the WEP matrix and help to form stable reinforcing and conductive networks, leading to great changes in the mechanical properties and resistivity of the composite. The composite film can withstand large deformations (>55% strain), and the resistance change rate demonstrates a high sensitivity to mechanical strain with a gauge factor of 34-71. Within a 4% strain range, the piezoresistive property of the composite is stable with good linearity and repeatability. The performance of the flexible film sensor made of the composite is tested and it can monitor the strain and crack of the concrete surface well.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31544334

RESUMO

Selective transport and concentration of molecules to specified regions on a substrate both enhances the potential to detect such molecules and provides a path to spatially localize such molecules prior to initiation of subsequent chemical reactions. Here, we first embed radially symmetric α-, ß-, and γ-cyclodextrin gradients in a hydrogel matrix. Driven by host-guest interactions between the cyclodextrins and the target molecule, we observe these gradients can serve to direct 2D molecular transport. Using xanthene dyes and organophosphates as target molecules, we found the transport metrics, e.g., selectivity, rate, and concentration limits, are strongly dependent on the specific cyclodextrin forming the gradient. In all cases, as the concentrating power of the gradient increased, the rate of target concentration slowed, which we hypothesize is because stronger interactions between the target and the cyclodextrin decrease the rate of target diffusion. The concentration enhancement for the nerve agent simulant 4-methylumbelliferyl phosphate (15.8) is the greatest when the gradient is formed using ß-cyclodextrin while directed concentration of cyanomethyl phosphonate, a smaller non-aromatic organophosphate, is observed only for the smaller α-CD. To provide a near real-time read-out of the concentration of the analyte, we used an array of IR resonant metallic nanoantennas tuned to a specific IR absorption band of the analyte to enhance the IR signal generated by the analyte.

18.
J Clin Neurosci ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31477463

RESUMO

Electroacupuncture (EA) is an adjuvant therapy for peripheral nerve injury (PNI). Both peripheral and central alterations contribute to the rehabilitation process. We employed diffusion tensor imaging (DTI) to investigate the diffusion plasticity of afferent and efferent pathways caused by EA in model of peripheral nerve injury and reparation. Twenty-four rats were divided into three groups: normal group, model group and intervention group. Rats of the model group and the intervention group underwent sciatic nerve transection and anastomosis. EA intervention was performed on the intervention group at ST-36 and GB-30 for three months. Gait assessment and DTI were conducted at days post-operative (DPO) 30, 60 and 90. We selected corticospinal tract, spinothalamic tract and internal capsule as regions of interest and analyzed diffusion metrics including fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD). FA values and RD values displayed significant differences or obvious tendency while AD values maintained a stable level. RD values displayed better indicative performance than FA in internal capsule. The intervention group presented significant correlation between RD values and Regularity Index (RI) during the intervention period. The effect of EA on peripheral nerve injury repairing rats appeared to be accelerated recovery process of sensory and motor neural pathway. We proposed that RD was a potential in vivo indicator for structural plasticity caused by EA and PNI.

19.
Nanotechnology ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31557740

RESUMO

Spin transfer nano-oscillators (STNOs) are a new type of radio frequency (RF) oscillators that utilize the current-induced magnetization precession in a magnetic tunnel junction (MTJ) device to generate high frequency microwave signal. Since both the frequency and the amplitude of STNOs can be tuned by changing the current, they are potentially used for amplitude shift keying (ASK) and frequency shift keying (FSK) modulation without the need for an RF mixer, which leads to compact RF components. In this letter, a novel strategy is proposed to modulate the frequency and the amplitude by memristor-controlled spin nano-oscillators (MSNs), whereby the STNO is responsible for microwave emitting and memristor serves as a current regulator which further modulates the frequency and amplitude. In addition, the I-V curves show that a multilevel resistance behavior can also be achieved in the same architecture.

20.
New Phytol ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529514

RESUMO

Histone 3 Lysine 4 (H3K4) demethylation is ubiquitous in organisms; however, the roles of H3K4 demethylase JARID1(Jar1)/KDM5 in fungal development and pathogenesis remain largely unexplored. Here, we demonstrate that Jar1/KDM5 in Botrytis cinerea, the gray mold fungus, plays crucial roles in these processes. The BcJAR1 gene was deleted and its roles in the fungal development and pathogenesis were investigated using approaches including genetics, molecular/cell biology, pathogenicity, and transcriptomic profiling. BcJar1 regulates H3K4me3 and both H3K4me2 and H3K4me3 methylation levels during vegetative and pathogenic development, respectively. Loss of BcJAR1 impairs conidiation, appressorium formation, and stress adaptation; abolishes infection cushion (IC) formation and virulence, but promotes sclerotium production in the ΔBcjar1 mutants. BcJar1 controls reactive oxygen species (ROS) production and proper assembly of Sep4, a core septin protein and virulence determinant, to initiate infection structure (IFS) formation and host penetration. Exogenous cAMP partially restored the mutant appressorium, but not IC, formation. BcJar1 orchestrates global expression of genes for ROS-production, stress response, carbohydrate transmembrane transport, secondary metabolites, etc., which may be required for conidiation, IFS formation, host penetration, and virulence of the pathogen. Our work systematically elucidates BcJar1 functions and provides novel insights into Jar1/KDM5-mediated H3K4 demethylation in regulating fungal development and pathogenesis.

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