Publications by authors named "Junpeng Wang"

116 Publications

Visual Analytics for RNN-Based Deep Reinforcement Learning.

IEEE Trans Vis Comput Graph 2021 Apr 30;PP. Epub 2021 Apr 30.

Deep reinforcement learning (DRL) targets to train an autonomous agent to interact with a pre-defined environment and strives to achieve specific goals through deep neural networks (DNN). Recurrent neural network (RNN) based DRL has demonstrated superior performance, as RNNs can effectively capture the temporal evolution of the environment and respond with proper agent actions. However, apart from the outstanding performance, little is known about how RNNs understand the environment internally and what has been memorized over time. Revealing these details is extremely important for deep learning experts to understand and improve DRLs, which in contrast, is also challenging due to the complicated data transformations inside these models. In this paper, we propose Deep Reinforcement Learning Interactive Visual Explorer (DRLIVE), a visual analytics system to effectively explore, interpret, and diagnose RNN-based DRLs. Focused on DRL agents trained for different Atari games, DRLIVE targets to accomplish three tasks: game episode exploration, RNN hidden/cell state examination, and interactive model perturbation. Using the system, one can flexibly explore a DRL agent through interactive visualizations, discover interpretable RNN cells by prioritizing RNN hidden/cell states with a set of metrics, and further diagnose the DRL model by interactively perturbing its inputs. Through concrete studies with multiple deep learning experts, we validated the efficacy of DRLIVE.
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http://dx.doi.org/10.1109/TVCG.2021.3076749DOI Listing
April 2021

Interactive Focus+Context Rendering for Hexahedral Mesh Inspection.

IEEE Trans Vis Comput Graph 2021 Apr 20;PP. Epub 2021 Apr 20.

The visual inspection of a hexahedral mesh with respect to element quality is difficult due to clutter and occlusions that are produced when rendering all element faces or their edges simultaneously. Current approaches overcome this problem by using focus on specific elements that are then rendered opaque, and carving away all elements occluding their view. In this work, we make use of advanced GPU shader functionality to generate a focus+context rendering that highlights the elements in a selected region and simultaneously conveys the global mesh structure in the surrounding. To achieve this, we propose a gradual transition from edge-based focus rendering to volumetric context rendering, by combining fragment shader-based edge and face rendering with per-pixel fragment lists. A fragment shader smoothly transitions between wireframe and face-based rendering, including focus-dependent rendering style and depth-dependent edge thickness and halos, and per-pixel fragment lists are used to blend fragments in correct visibility order. To maintain the global mesh structure in the context regions, we propose a new method to construct a sheet-based level-of-detail hierarchy and smoothly blend it with volumetric information. The user guides the exploration process by moving a lens-like hotspot. Since all operations are performed on the GPU, interactive frame rates are achieved even for large meshes.
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http://dx.doi.org/10.1109/TVCG.2021.3074607DOI Listing
April 2021

Deployment of a bioabsorbable plate as the rigid buttress for skull base repair after endoscopic pituitary surgery.

Gland Surg 2021 Mar;10(3):1010-1017

Department of Neurosurgery, Qilu Hospital of Shandong University, Jinan, China.

Background: Bioresorbable alloplastic implants have become desirable as a rigid buttress for reconstructing skull base defects. This study aimed to describe the use of a biodegradable plate (PolyMax RAPID) in skull base repair of endoscopic endonasal pituitary surgery and to investigate the clinical outcome and safety of this novel method.

Methods: Between January 2019 and January 2020, 22 patients with pituitary adenomas who underwent endoscopic skull base repair with a Polymax RAPID plate were included. After endonasal transsphenoidal surgery, a trimmed bioresorbable plate was placed in the position between the dura and the bone of the skull base to reconstruct the sellar floor and buttress the pituitary gland and sellar packing. The patient demographics, radiologic imaging, and postoperative outcomes were carefully reviewed. All patients were followed up by a routine nasal endoscopic assessment and radiologic examinations.

Results: The present study comprised 10 (45.5%) males and 12 (54.4%) females with an average age of 51.9 years. There were 7 (31.8%) growth hormone (GH) secreting adenomas, 2 (9.1%) thyroid stimulating hormone (TSH) secreting adenomas, and 13 (59.1%) non-functioning adenomas. Enlarged sellar floor and paranasal sinusitis were seen in 13 (59.1%) and 11 (50.0%) cases shown by preoperative computed tomography (CT) or magnetic resonance imaging (MRI), respectively. There were 6 (27.3%) grade-1 and 16 (72.7%) grade-0 cases by intraoperative cerebrospinal fluid (CSF) leak grading. None of these patients received lumbar drains postoperatively and no postoperative CSF rhinorrhea was detected in our series. The PolyMax RAPID plates which could be clearly identified on postoperative CT or sagittal T1-weighted MRI were shown to provide an ideal rigid buttress for sellar repair.

Conclusions: The Polymax RAPID plate can be an optimal implant to achieve rigid repair of sellar floor defects after endonasal transsphenoidal pituitary surgery.
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http://dx.doi.org/10.21037/gs-20-642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033064PMC
March 2021

Gut microbiota alterations associated with antibody-mediated rejection after kidney transplantation.

Appl Microbiol Biotechnol 2021 Mar 24;105(6):2473-2484. Epub 2021 Feb 24.

Department of Urology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Zhengzhou, 450003, China.

Antibody-mediated rejection (AMR) has become the major challenge for kidney transplantation, and the efficacy of existing therapies was limited to prevent AMR. Increasing evidences have demonstrated the link between gut microbiota alterations and allograft outcome. However, there has been no comprehensive analysis to profile the gut microbiota associated with AMR after kidney transplantation. We performed this study to characterize the gut microbiota possibly associated with AMR. Fecal specimens were collected from 24 kidney transplantation recipients with AMR and 29 controls. DNA extracted from the specimens was processed for 16S rRNA gene sequencing using Illumina MiSeq. Gut microbial community of recipients with AMR was significantly different from that of controls based on unweighted (P = 0.001) and weighted (P = 0.02) UniFrac distances, and the bacterial richness (observed species: P = 0.0448; Chao1 index: P = 0.0450; ACE index: P = 0.0331) significantly decreased in the AMR group. LEfSe showed that 1 phylum, 5 classes, 7 families, and 10 genera were increased, whereas 1 class, 2 order, 3 families, and 4 genera were decreased in the AMR group. Specific taxa such as Clostridiales could be potentially used as biomarkers to distinguish the recipients with AMR from the controls (AUC = 0.77). PICRUSt analysis illustrated that 16 functional pathways were with significantly different abundances in the AMR and control groups. Our findings provide a foundation for further investigation on the role of gut microbiota in AMR after kidney transplantation, and potentially support novel diagnostic biomarkers and therapeutic options for AMR. KEY POINTS: • Gut microbial community of kidney recipients with AMR was different from that of controls. • Clostridiales is a potential marker to distinguish recipients with AMR from controls.
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http://dx.doi.org/10.1007/s00253-020-11069-xDOI Listing
March 2021

Corrigendum: Polyphenols Attenuate Inflammatory Response Modulating the Crosstalk Between Macrophages and Adipocytes.

Front Immunol 2021 28;12:633354. Epub 2021 Jan 28.

Institute of Infection and Immunity of Huaihe Hospital, Henan University, Kaifeng, China.

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http://dx.doi.org/10.3389/fimmu.2021.633354DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7877251PMC
January 2021

Loss of COPZ1 induces NCOA4 mediated autophagy and ferroptosis in glioblastoma cell lines.

Oncogene 2021 Feb 8;40(8):1425-1439. Epub 2021 Jan 8.

Department of Neurosurgery, Qilu Hospital and Institute of Brain and Brain-Inspired Science, Cheeloo College of Medicine, Shandong University, Shandong, 107 Wenhua Xi Road, Jinan, 250012, P.R. China.

Dysregulated iron metabolism is a hallmark of many cancers, including glioblastoma (GBM). However, its role in tumor progression remains unclear. Herein, we identified coatomer protein complex subunit zeta 1 (COPZ1) as a therapeutic target candidate which significantly dysregulated iron metabolism in GBM cells. Overexpression of COPZ1 was associated with increasing tumor grade and poor prognosis in glioma patients based on analysis of expression data from the publicly available database The Cancer Genome Atlas (P < 0.001). Protein levels of COPZ1 were significantly increased in GBM compared to non-neoplastic brain tissue samples in immunohistochemistry and western blot analysis. SiRNA knockdown of COPZ1 suppressed proliferation of U87MG, U251 and P3#GBM in vitro. Stable expression of a COPZ1 shRNA construct in U87MG inhibited tumor growth in vivo by ~60% relative to controls at day 21 after implantation (P < 0.001). Kaplan-Meier analysis of the survival data demonstrated that the overall survival of tumor bearing animals increased from 20.8 days (control) to 27.8 days (knockdown, P < 0.05). COPZ1 knockdown also led to the increase in nuclear receptor coactivator 4 (NCOA4), resulting in the degradation of ferritin, and a subsequent increase in the intracellular levels of ferrous iron and ultimately ferroptosis. These data demonstrate that COPZ1 is a critical mediator in iron metabolism. The COPZ1/NCOA4/FTH1 axis is therefore a novel therapeutic target for the treatment of human GBM.
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http://dx.doi.org/10.1038/s41388-020-01622-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7906905PMC
February 2021

Naringenin attenuates experimental autoimmune encephalomyelitis by protecting the intact of blood-brain barrier and controlling inflammatory cell migration.

J Nutr Biochem 2021 03 26;89:108560. Epub 2020 Nov 26.

Institute of Infection and Immunity and Translational Medical Center, Huaihe Hospital of Henan University, Kaifeng 475000, China. Electronic address:

Targeting pathogenic immune cell trafficking poses an attractive opportunity to attenuate autoimmune disorders such as multiple sclerosis (MS). MS and its animal model, experimental autoimmune encephalomyelitis (EAE), are characterized by the immune cells-mediated demyelination and neurodegeneration of the central nervous system (CNS). Our previous study has proven that dietary naringenin ameliorates EAE clinical symptoms via reducing the CNS cell infiltration. The present study examined the beneficial effects of naringenin on maintaining the blood-brain barrier in EAE mice via dietary naringenin intervention. The results showed that naringenin-treated EAE mice had an intact blood-CNS barrier by increasing tight junction-associated factors and decreasing Evans Blue dye in the CNS. Naringenin decreased the accumulation and maturation of conventional dendritic cells (cDCs), CCL19, and CCR7 in the CNS. Also, naringenin blocked the chemotaxis and antigen-presenting function of cDCs that resulted in reducing T-cell secreting cytokines (IFN-γ, IL-17, and IL-6) in the spleen. Importantly, naringenin blocked pathogenic T cells infiltrated into the CNS and attenuates passive EAE. Therefore, by blocking chemokine-mediated migration of DCs and pathogenic T cells into the CNS, naringenin attenuates EAE pathogenesis and might be a potential candidate for the treatment of autoimmune diseases, such as MS and other chronic T-cell mediated autoimmune diseases.
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http://dx.doi.org/10.1016/j.jnutbio.2020.108560DOI Listing
March 2021

Uncovering the microbiota in renal cell carcinoma tissue using 16S rRNA gene sequencing.

J Cancer Res Clin Oncol 2021 Feb 21;147(2):481-491. Epub 2020 Nov 21.

Department of Urology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Zhengzhou, 450003, China.

Introduction: Increasing evidence indicates an important role of microbiota in cancer development and progression, while little is known about the correlation between microbiota and renal cell carcinoma (RCC). Thus, we performed this study to profile the intratumoral microbiota possibly associated with RCC.

Materials And Methods: Paired RCC and adjacent normal tissue samples were collected from 24 patients with RCC. V3-V4 variable region of microbial 16S rRNA gene was sequenced using Illumina MiSeq. Sequencing reads were processed using QIIME. Differentially abundant bacterial taxa between groups were identified by LEfSe, and their potential functions were inferred by PICRUSt.

Results: Decreased species diversity was presented in RCC tissues (Simpson index, P = 0.0340), and the composition of the bacterial community in RCC tissues was significantly distinct from that in normal tissues (unweighted UniFrac distance, P = 0.026; weighted UniFrac distance, P = 0.017). Compared with normal tissues, 25 taxa increased and 47 reduced taxa were identified in RCC tissues. Among these taxa, the class Chloroplast (AUC = 0.91, P < 0.0001) and the order Streptophyta (AUC = 0.89, P < 0.0001) showed high indication accuracy to discriminate RCC tissues from normal tissues. Furthermore, nine altered pathways were identified in RCC tissues to reveal the potential microbial function.

Conclusions: Our results have uncovered the presence of distinct microbiota in RCC and adjacent normal tissues and provided a better understanding of the possible role of the intratumoral microbiota in RCC. Further studies are required to confirm our results and determine the real correlation between microbiota and RCC.
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http://dx.doi.org/10.1007/s00432-020-03462-wDOI Listing
February 2021

Mushroom Inonotus sanghuang alleviates experimental pulmonary fibrosis: Implications for therapy of pulmonary fibrosis.

Biomed Pharmacother 2021 Jan 14;133:110919. Epub 2020 Nov 14.

Institute of Infection and Immunity and Translational Medical Center, Huaihe Hospital of Henan University, Kaifeng, 475000, China. Electronic address:

Mushroom Inonotus sanghuang has been characterized as a traditional medicine in China and has pharmacological activities to treat inflammation, gastroenteric dysfunction, and cancer. Recently, we reported the impact of Inonotus sanghuang extract (ISE) from ethyl acetate fraction on bleomycin (BLM)-induced acute lung injury in mice. Here, we aimed to investigate ISE's impact on pulmonary fibrosis using in vivo and in vitro models and the underlying mechanisms. To evaluate pulmonary fibrosis, female C57BL/6 mice fed ISE (0% or 0.6% in diet) for 4 weeks were instilled intratracheally with BLM and then continued the same diet before the end of the experiment. A549 cells were used to evaluate the epithelial-mesenchymal transition (EMT). Feeding ISE improved BLM-treated mice's survival via decreasing lung infiltrating cells and fibrosis, followed by reducing hydroxyproline content, collagen deposition, and mesenchymal markers (α-SMA and vimentin) while increasing epithelial marker E-cadherin. ISE also suppressed the TGF-β expression, Smad2/3 phosphorylation, and EMT-related transcription factor Snail upon BLM instillation. Iin vitro study demonstrated that ISE inhibited TGF-β-induced EMT-like phenotype and cell behaviors, the expression of α-SMA and vimentin, and prevented E-cadherin reduction of A549 cells. Consistent with in vivo study, ISE abrogated p-Smad2/3, and Snail expression. Finally, the influence of ISE on EMT was not due to ISE toxicity. Our findings indicated that ISE effectively attenuated BLM-induced lung fibrosis. These ISE properties were thought to be involved in interfering TGF-β, Smad2/3 phosphorylation, and EMT process, suggesting that the material has the potential health benefits to improve lung fibrosis.
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http://dx.doi.org/10.1016/j.biopha.2020.110919DOI Listing
January 2021

Mushroom Modulates Host Immunological Response and Gut Microbiota in Mice.

Front Nutr 2020 8;7:144. Epub 2020 Oct 8.

Institute of Infection and Immunity and Translational Medical Center, Huaihe Hospital of Henan University, Kaifeng, China.

We aimed to determine the prebiotic impact of Mushroom (BI) on the host immune response and gut microbiota. Male C57BL/6 mice were fed a diet supplemented with 0, 1, or 2% BI for 4 wks. Compared to mice fed with a control diet (0% BI), mice fed with 1 or 2% BI had an increase of T cell proliferation from the spleen, but such change was not found between 1 and 2% BI treated mice. Also, BI at 2% increased the production of IL-2 of splenocytes stimulated with T-cell mitogens, but BI at 1 and 2% did not affect productions of other splenic-T cell cytokines including IL-4, IL-10, and IFN-γ. Interestingly, BI at 1 or 2% inhibited T cell proliferation of mesenteric lymph node (mLN) but this effect was not found between 1 and 2% BI treated mice. Furthermore, BI inhibited the production of IL-2 in anti-CD3/CD28-stimulated T cells from mLN in a dose-dependent manner. Meanwhile, BI at 2%, not 1% inhibited the production of IL-4, IL-10, and IFN-γ of mLN. Since BI at 2% produced a more significant effect on the immune response, we further used BI at 2% to evaluate the effect of BI on gut microbiota. Of note, BI reduced the diversity of gut microbiota and resulted in an increase of and abundance and the decrease of _, and abundance at the genus level. Finally, the correlation was observed between specific bacteria genera and the productions of T-cell cytokines from mesenteric lymphocytes: and correlated positively with IL-2, IL-4, IL-10, and IFN-γ; and correlated negatively with IL-2 and IL-4; correlated negatively with IFN-γ and IL-4 and and correlated negatively with IFN-γ. The specific role of each intestinal microbiota observed is still unclear, but BI might exert a prebiotic effect on gut microbiota by increasing the abundance of potentially beneficial bacteria (). This is helpful for further demonstrating the healthy-promotion mechanism of .
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http://dx.doi.org/10.3389/fnut.2020.00144DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7578393PMC
October 2020

CNNPruner: Pruning Convolutional Neural Networks with Visual Analytics.

IEEE Trans Vis Comput Graph 2021 Feb 28;27(2):1364-1373. Epub 2021 Jan 28.

Convolutional neural networks (CNNs) have demonstrated extraordinarily good performance in many computer vision tasks. The increasing size of CNN models, however, prevents them from being widely deployed to devices with limited computational resources, e.g., mobile/embedded devices. The emerging topic of model pruning strives to address this problem by removing less important neurons and fine-tuning the pruned networks to minimize the accuracy loss. Nevertheless, existing automated pruning solutions often rely on a numerical threshold of the pruning criteria, lacking the flexibility to optimally balance the trade-off between efficiency and accuracy. Moreover, the complicated interplay between the stages of neuron pruning and model fine-tuning makes this process opaque, and therefore becomes difficult to optimize. In this paper, we address these challenges through a visual analytics approach, named CNNPruner. It considers the importance of convolutional filters through both instability and sensitivity, and allows users to interactively create pruning plans according to a desired goal on model size or accuracy. Also, CNNPruner integrates state-of-the-art filter visualization techniques to help users understand the roles that different filters played and refine their pruning plans. Through comprehensive case studies on CNNs with real-world sizes, we validate the effectiveness of CNNPruner.
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http://dx.doi.org/10.1109/TVCG.2020.3030461DOI Listing
February 2021

Capability of Penicillium oxalicum y2 to release phosphate from different insoluble phosphorus sources and soil.

Folia Microbiol (Praha) 2021 Feb 17;66(1):69-77. Epub 2020 Sep 17.

Department of Microbiology, Hazara University, Mansehra, Pakistan.

Due to insufficient amount of soluble phosphate and poor persistence of traditional chemical phosphate fertilizers in agricultural soils, the eco-friendly and sustainable phosphorus sources for crops are urgently required. The efficient phosphate-releasing fungal strain designated y2 was isolated and identified by the internal transcribed spacer of rDNA as Penicillium oxalicum y2. When lecithin, Ca(PO), or ground phosphate rock were separately used as sole phosphorus source, different phosphate-releasing modes were observed. The strain y2 was able to release as high as 2090 mg/L soluble phosphate within 12 days of incubation with Ca(PO) as sole phosphorus source. In the culture solution, high concentration of oxalic, citric, and malic acids and high phosphatase activity were detected. The organic acids contributed to solubilizing inorganic phosphate sources, while phosphatase was in charge of the mineralization of organic phosphorus lecithin. Afterwards, the fungus culture was applied to the soil with rape growing. During 50 days of incubation, the soil's available phosphate concentration increased by three times compared with the control, the dry weight of rape increased by 78.73%, and the root length increased by 38.79%. The results illustrated that P. oxalicum y2 possessed both abilities of solubilizing inorganic phosphorus and mineralizing organic phosphorus, which have great potential application in providing biofertilizer for modern agriculture.
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http://dx.doi.org/10.1007/s12223-020-00822-4DOI Listing
February 2021

Glioblastoma Therapy Using Codelivery of Cisplatin and Glutathione Peroxidase Targeting siRNA from Iron Oxide Nanoparticles.

ACS Appl Mater Interfaces 2020 Sep 17;12(39):43408-43421. Epub 2020 Sep 17.

Department of Neurosurgery, Qilu Hospital and Institute of Brain and Brain-Inspired Science, Cheeloo College of Medicine, Shandong University, 107 Wenhua Xi Road, Jinan, Shandong 250012, P. R. China.

Glioblastoma (GBM) is the most common and lethal type of malignant brain tumor in adults. Currently, interventions are lacking, the median overall survival of patients with GBM is less than 15 months, and the postoperative recurrence rate is greater than 60%. We proposed an innovative local chemotherapy involving the construction of gene therapy-based iron oxide nanoparticles (IONPs) as a treatment for patients with glioblastoma after surgery that targeted ferroptosis and apoptosis to address these problems. The porous structure of IONPs with attached carboxyl groups was modified for the codelivery of small interfering RNA (siRNA) targeting glutathione peroxidase 4 (si-GPX4) and cisplatin (Pt) with high drug loading efficiencies. The synthesized folate (FA)/Pt-si-GPX4@IONPs exerted substantial effects on glioblastoma in U87MG and P3#GBM cells, but limited effects on normal human astrocytes (NHAs). During intracellular degradation, IONPs significantly increased iron (Fe and Fe) levels, while Pt destroyed nuclear DNA and mitochondrial DNA, leading to apoptosis. Furthermore, IONPs increased HO levels by activating reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX). The Fenton reaction between Fe, Fe, and intracellular HO generated potent reactive oxygen species (ROS) to initiate ferroptosis, while the co-released si-GPX4 inhibited GPX4 expression and synergistically improved the therapeutic efficacy through a mechanism related to ferroptosis. As a result, superior therapeutic effects with low systemic toxicity were achieved both and , indicating that our nanoformulations might represent safe and efficient ferroptosis and apoptosis inducers for use in combinatorial glioblastoma therapy.
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http://dx.doi.org/10.1021/acsami.0c12042DOI Listing
September 2020

Unexpectedly high stability and surface reconstruction of PdAuAg nanoparticles for formate oxidation electrocatalysis.

Nanoscale 2020 Jun;12(21):11659-11671

State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China. and School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, China.

High-performance Pd-based nanocatalysts for alkaline methanol and formate fuel cells have stimulated widespread attention. Hence, a series of ternary Pd-Au-Ag nanoalloys have been synthesized on carbon nanotubes, which demonstrate promising activity and unexpectedly high stability for the formate oxidation reaction (FOR) in alkaline medium. The ternary Pd3Au3Ag1 nanoalloy catalyst showed an initial mass activity of 4.51 A mgPd-1 and a retained mass activity of 1.32 A mgPd-1 after chronoamperometric measurement for 3600 s, which are superior to the best values for all FOR catalysts reported so far. The Pd3Au3Ag1 catalyst also showed a good specific activity of 4.32 mA cm-2 for the methanol oxidation reaction. Furthermore, surface reconstruction of the Pd3Au3Ag1 nanoalloy was observed during FOR, where the activity of Pd3Au3Ag1 catalysts increased up to 33% and the cycling durability retained 55% after cyclic voltammetry with the upper potential of 1.7 V. The FOR enhancement is attributed to the formation of mixed oxidation-state Ag sites and the increase in the Pd surface coverage, and provides a new prospect for the design of ternary nanoalloy electrocatalysts for various fuel oxidation reactions.
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http://dx.doi.org/10.1039/d0nr01358gDOI Listing
June 2020

Strategies for prevention and control of the 2019 novel coronavirus disease in the department of kidney transplantation.

Transpl Int 2020 09 27;33(9):1040-1045. Epub 2020 May 27.

Department of urology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Zhengzhou, China.

To summarize measures for the prevention and control of the 2019 novel coronavirus disease (COVID-19) in the department of kidney transplantation. We retrospectively analyzed the clinical data of outpatients and inpatients in the department of kidney transplantation from January 20 to March 1, 2020, and followed up the in-home kidney transplant recipients and those waiting for kidney transplantation through the Internet platform. Our department had formulated detailed prevention and control measures, mainly including kidney transplant outpatient management, kidney transplantation ward management, management of kidney transplant surgery, dialysis management of patients waiting for kidney transplantation, personal protection of medical staff, and follow-up management of discharged patients after kidney transplantation. During the epidemic period, there were no COVID-19 cases among 68 outpatient examined kidney transplant recipients, 32 hospitalized kidney transplant recipients, 19 patients waiting for kidney transplantation in hospital, and 30 medical staff. There were no COVID-19 cases among 160 follow-up recipients after kidney transplantation and 60 patients waiting for kidney transplantation. During the epidemic period, we implemented strict prevention and control measures and adjusted working methods and procedures to ensure safe and orderly work of the department.
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http://dx.doi.org/10.1111/tri.13634DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7267566PMC
September 2020

COVID-19 in a Kidney Transplant Patient.

Eur Urol 2020 06 6;77(6):769-770. Epub 2020 Apr 6.

Department of Urology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Zhengzhou, China. Electronic address:

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http://dx.doi.org/10.1016/j.eururo.2020.03.036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271211PMC
June 2020

A Polymer with "Locked" Degradability: Superior Backbone Stability and Accessible Degradability Enabled by Mechanophore Installation.

J Am Chem Soc 2020 02 22;142(5):2100-2104. Epub 2020 Jan 22.

Department of Polymer Science , The University of Akron , Akron , Ohio 44325 , United States.

Though numerous applications require degradable polymers, there are surprisingly few polymer systems that combine superior stability and controllable degradability. Particularly, the degradability of a conventional degradable polymer is typically enabled by cleavable groups on the backbone, which can be attacked by stimuli in ambient conditions, causing undesirable material deterioration. Here we report a general strategy to overcome this issue: "locking" the degradability during handling and use of the polymers and "unlocking" it when degradation is needed. This strategy is demonstrated with a cyclobutane-fused lactone (CBL) polymer. The cyclobutane keeps polymer backbone intact under conditions that hydrolyze the lactone and allows the ester group to be recovered when undesirable hydrolysis occurs. When backbone degradation is needed, the degradability can be unlocked by mechanochemical activation that converts the polyCBL into a linear polyester. The rare combination of two intrinsically conflicting properties, i.e., backbone stability and accessible degradability, can make this polymer a potential option for new sustainable materials.
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http://dx.doi.org/10.1021/jacs.9b12482DOI Listing
February 2020

Global Transcriptome and Co-Expression Network Analysis Reveal Contrasting Response of and Rice Cultivar to γ Radiation.

Int J Mol Sci 2019 Sep 5;20(18). Epub 2019 Sep 5.

Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.

and are two important subspecies in cultivated Asian rice. Irradiation is a classical approach to induce mutations and create novel germplasm. However, little is known about the differential response between and rice after γ radiation. Here, we utilized the RNA sequencing and Weighted Gene Co-expression Network Analysis (WGCNA) to compare the transcriptome differences between Nipponbare (NPB) and Yangdao6 (YD6) in response to irradiation. subspecies are more sensitive to irradiation than the subspecies. showed a higher seedling survival rate than . Irradiation caused more extensive DNA damage in shoots than in roots, and the severity was higher in NPB than in YD6. GO and KEGG pathway analyses indicate that the core genes related to DNA repair and replication and cell proliferation are similarly regulated between the varieties, however the universal stress responsive genes show contrasting differential response patterns in and . WGCNA identifies 37 co-expressing gene modules and ten candidate hub genes for each module. This provides novel evidence indicating that certain peripheral pathways may dominate the molecular networks in irradiation survival and suggests more potential target genes in breeding for universal stress tolerance in rice.
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http://dx.doi.org/10.3390/ijms20184358DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6769861PMC
September 2019

Role of immune checkpoint inhibitor-based therapies for metastatic renal cell carcinoma in the first-line setting: A Bayesian network analysis.

EBioMedicine 2019 Sep 19;47:78-88. Epub 2019 Aug 19.

Department of Urology, Henan Provincial People's Hospital; Zhengzhou University People's Hospital, Zhengzhou 450003, China. Electronic address:

Background: Several novel immune checkpoint inhibitor (ICI)-based treatments exhibited promising survival benefits for metastatic renal cell carcinoma (mRCC), yet there is no current guidance regarding the optimum first-line regimen. We performed this network analysis to compare the efficacy and safety of all available treatments for mRCC.

Methods: A systematic search of literature was conducted up to April 30, 2019, and the analysis was done on a Bayesian fixed-effect model.

Findings: Twenty-five randomized clinical trials (RCTs) involving 13,010 patients were included in this study. The results showed that for overall survival, pembrolizumab plus axitinib (hazard ratio [HR]: 0.53; 95% credible interval [CrI]: 0.38-0.73) and nivolumab plus ipilimumab (HR: 0.63; 95% CrI: 0.50-0.79) were significantly more effective than sunitinib, and pembrolizumab plus axitinib was probably (68%) to be the best choice. For progression-free survival, cabozantinib (HR: 0.66; 95% CrI: 0.46-0.94), pembrolizumab plus axitinib (HR: 0.69; 95% CrI: 0.57-0.84), avelumab plus axitinib (HR: 0.69; 95% CrI: 0.56-0.85), nivolumab plus ipilimumab (HR: 0.82; 95% CrI: 0.68-0.99), and atezolizumab plus bevacizumab (HR: 0.86; 95% CrI: 0.74-0.99) were statistically superior to sunitinib, and cabozantinib was likely (43%) to be the preferred options. Nivolumab plus ipilimumab (OR: 0.50; 95% CrI: 0.28-0.84), and atezolizumab plus bevacizumab (OR: 0.56; 95% CrI: 0.36-0.83) were associated with significantly lower rate of high-grade adverse events than sunitinib.

Interpretation: Our findings demonstrate that pembrolizumab plus axitinib might be the best treatment for mRCC, while nivolumab plus ipilimumab has the most favorable balance between efficacy and acceptability, and may provide new guidance to make treatment decisions. FUND: This research was supported by the Henan Provincial Scientific and Technological Research Project (Grant No. 192102310036).
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http://dx.doi.org/10.1016/j.ebiom.2019.08.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6796578PMC
September 2019

InSituNet: Deep Image Synthesis for Parameter Space Exploration of Ensemble Simulations.

IEEE Trans Vis Comput Graph 2020 Jan 19;26(1):23-33. Epub 2019 Aug 19.

We propose InSituNet, a deep learning based surrogate model to support parameter space exploration for ensemble simulations that are visualized in situ. In situ visualization, generating visualizations at simulation time, is becoming prevalent in handling large-scale simulations because of the I/O and storage constraints. However, in situ visualization approaches limit the flexibility of post-hoc exploration because the raw simulation data are no longer available. Although multiple image-based approaches have been proposed to mitigate this limitation, those approaches lack the ability to explore the simulation parameters. Our approach allows flexible exploration of parameter space for large-scale ensemble simulations by taking advantage of the recent advances in deep learning. Specifically, we design InSituNet as a convolutional regression model to learn the mapping from the simulation and visualization parameters to the visualization results. With the trained model, users can generate new images for different simulation parameters under various visualization settings, which enables in-depth analysis of the underlying ensemble simulations. We demonstrate the effectiveness of InSituNet in combustion, cosmology, and ocean simulations through quantitative and qualitative evaluations.
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http://dx.doi.org/10.1109/TVCG.2019.2934312DOI Listing
January 2020

Multilevel Effective Heterojunctions Based on SnO/ZnO 1D Fibrous Hierarchical Structure with Unique Interface Electronic Effects.

ACS Appl Mater Interfaces 2019 Aug 14;11(34):31551-31561. Epub 2019 Aug 14.

School of Material Science and Engineering , University of Jinan , 250022 Jinan , P. R. China.

One-step single-spinneret electrospinning synthesis of 1D fibrous hierarchical structure can not only prevent the agglomeration or restacking of fibers or particles and enlarge surface active area but also promote the directional migration of electrons in materials and achieve effective regulation of resistances. Herein, tunable SnO and SnO/ZnO fibrous hierarchical structures with in situ growth of monodisperse spherical-like particles on surface provide a new sight for adjusting component distribution, surface absorption and chemical reaction, electronic transmission path, and electron transfer efficiency. Compared with SnO porous fibers and SnO hierarchical structures, the optimal SnO/ZnO sensors exhibit superior gas-sensing response value of 366-100 ppm ethanol at 260 °C as well as excellent gas selectivity and long-term stability, in which the enhanced gas-sensing mechanism is primarily derived from multilevel effective heterojunctions with unique interface electronic effects. Especially, these SnO-based sensors can achieve favorable linear relationship of the response and gas concentration for sensitive trace detection in cosmetics for the first time, providing a new strategy to design composite materials for quantitative analysis of volatiles in the cosmetics evaluation process.
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http://dx.doi.org/10.1021/acsami.9b10410DOI Listing
August 2019

Expression Profiling of Exosomal miRNAs Derived from the Peripheral Blood of Kidney Recipients with DGF Using High-Throughput Sequencing.

Biomed Res Int 2019 12;2019:1759697. Epub 2019 Jun 12.

Department of Urology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou 450003, China.

Delayed graft function (DGF) is one of the major obstacles for graft survival for kidney recipients. It is profound to reduce the incidence of DGF for maintaining long-term graft survival. However, the molecular regulation of DGF is still not adequately explained and the biomarkers for DGF are limited. Exosomes are cell-derived membrane vesicles, contents of which are stable and could be delivered into recipient cells to exert their biological functions. Consequently, exosome-derived proteomic and RNA signature profiles are often used to account for the molecular regulation of diseases or reflect the conditional state of their tissue as biomarkers. Few researches have been done to demonstrate the function of exosomes associated with DGF. In this study, high-throughput sequencing was used to explore the miRNA expression profiling of exosomes in the peripheral blood of kidney recipients with DGF. We identified 52 known and 5 conserved exosomal miRNAs specifically expressed in recipients with DGF. Three coexpressed miRNAs, hsa-miR-33a-5p_R-1, hsa-miR-98-5p, and hsa-miR-151a-5p, were observed to be significantly upregulated in kidney recipients with DGF. Moreover, hsa-miR-151a-5p was positively correlated with the first-week serum CR, BUN, and UA levels of the kidney recipients after transplantation. Furthermore, we also analyzed functions and signaling pathways of the three upregulated miRNAs target genes to uncover putative mechanism of how these exosomal miRNAs functioned in DGF. Overall, these findings identified biomarker candidates for DGF and provided new insights into the important role of the exosomal miRNAs regulation in DGF.
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http://dx.doi.org/10.1155/2019/1759697DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6594342PMC
December 2019

Regenerated WO nanowires with superb fast and selective adsorption for cationic dye: Kinetics, isotherm, thermodynamics, mechanism.

J Hazard Mater 2019 11 27;379:120834. Epub 2019 Jun 27.

School of Materials Science and Engineering, University of Jinan, 250022, Jinan, PR China.

Hydrothermally prepared nonstoichiometry tungsten oxide (WO) nanowires possess super selective adsorption performance for methylene blue (MB). The effects of dye concentration, contact time, pH and temperature on the adsorption properties of WO were investigated. The experimental results indicated that WO nanowires have a high adsorption capacity (547.32 mg/g) under neutral pH and a fast adsorption rate (adsorbing 100% within 6 min) for MB dye. The kinetic data showed good correlation coefficient (R > 0.99) for the pseudo-second-order. The equilibrium data suggesting the monolayer coverage of adsorbate as it fits well with the Langmuir isotherm model (R > 0.99). The energy functions of chemical thermodynamics revealed the adsorbate transport across the phase boundary is spontaneous and exothermic. Electrostatic absorption was proposed as the main adsorption mechanisms. Calcination treatment was utilized to decompose MB adsorbed on WO and regenerate WO. The adsorption efficiency of WO nanowires can still reach 86.54% after recycling five times, which indicated that as-obtained WO nanowires are a very promising high-efficiency adsorbent for practical purification of dyeing waste water.
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http://dx.doi.org/10.1016/j.jhazmat.2019.120834DOI Listing
November 2019

An efficient utilization of high chromium vanadium slag: Extraction of vanadium based on manganese carbonate roasting and detoxification processing of chromium-containing tailings.

J Hazard Mater 2019 10 4;378:120733. Epub 2019 Jun 4.

School of Metallurgy, Northeastern University, Shenyang, 110819, Liaoning, China.

A novelty roasting method with manganese carbonate (MnCO) as additive was carried out to separate and recover vanadium from high chromium vanadium slag (HCVS) efficiently. Vanadium tailings containing chromium was detoxified by carbon reduction and smelting to form Fe-Cr alloy. The whole process of HCVS utilization was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). 89.37% of vanadium and 0.10% of chromium was leached when MnCO was added to HCVS at the mole ratio of MnO in MnCO and VO in HCVS (n(MnO)/n(VO)) of 2.0 and heating at 850 °C for 120 min, then leached under the pH value at 2.5. 99.19% of vanadium was precipitated by (NH)SO and VO with a purity of 99.28% was prepared. More than 84% of manganese addictive was recovered after manganese precipitation by carbonization with CO discharged from manganese carbonate roasting, which could be used as the raw addictive for roasting. The wastewater after vanadium and manganese extraction could be circulated as leaching medium. Three circulation routes realized the closed-circuit circulation of raw materials and products, saving the production costs and avoiding the environmental pollution. Fe-Cr alloy with 67.35% of Fe and 13.28% of Cr was obtained from chromium-containing vanadium tailings, which could be returned to the steelmaking process.
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http://dx.doi.org/10.1016/j.jhazmat.2019.06.010DOI Listing
October 2019

Counting loops in sidechain-crosslinked polymers from elastic solids to single-chain nanoparticles.

Chem Sci 2019 May 1;10(20):5332-5337. Epub 2019 May 1.

Department of Chemistry , Massachusetts Institute of Technology , Cambridge , MA 02139 , USA . Email:

The vast differences in material properties accessible crosslinking of sidechain-functionalized polymers are driven by topology. For example, vulcanized rubbery networks feature intermolecular connections and loop topologies of various orders while single-chain nanoparticles (SCNPs) are comprised, in principle, entirely of primary loops. Despite this fact, precise quantification of loops in sidechain crosslinked polymers has not been accomplished. Here, it is demonstrated that by introducing cleavable linkers and mass labels onto the pendant functional groups of reactive polymers, the number of primary loops in sidechain crosslinked materials ranging from rubbery networks (gels) to soluble SCNPs can be precisely quantified. This study sheds new light on the topology of sidechain-crosslinked networks, providing design principles for augmenting the properties of this industrially and academically important class of materials through topological control.
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http://dx.doi.org/10.1039/c9sc01297dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6540913PMC
May 2019

Protective effect of a polyphenols-rich extract from Inonotus Sanghuang on bleomycin-induced acute lung injury in mice.

Life Sci 2019 Aug 29;230:208-217. Epub 2019 May 29.

Institute of Infection and Immunity of Huaihe Hospital, Henan University, Kaifeng, 475000, China. Electronic address:

Mushroom Phellinus linteus ("Sanghuang" in Chinese) is a popular medicinal polypore used to treat several disorders through its various biological functions. Inonotus sanghuang is claimed to produce general immune-potentiating and strengthening, anti-inflammatory, anti-tumor and anti-microbial properties, but its effect on acute lung inflammation and oxidative stress are not clearly understood. To determine the effect and mechanism of the polyphenols-rich ethyl acetate fraction from wild I. sanghuang extract (ISE) on acute lung injury (ALI) induced by bleomycin (BLM), female C57BL/6 mice were fed ISE (0%, 0.15% or 0.6% in diet) for 4 weeks prior to challenge with BLM. Bronchoalveolar lavage fluid (BALF) from lung, spleen and lung tissues were collected on day 3 after BLM challenge for histological, oxidative stress, molecular and biochemical analysis. ISE supplementation improved pathological features in lung injury scores and reduced lung wet-to-dry ratios. Moreover, ISE reduced inflammatory cell infiltration and the pro-inflammatory cytokines including IL-1β, IL-6 and TNF-α in BALF, decreased the MPO activity and the MDA level and increased the SOD, CAT and GSH-Px activities in lung tissue homogenates. Further mechanism analysis demonstrated that dietary ISE inhibited NF-κB signal. Finally, peripheral immune function analysis showed that ISE had less effect on immune response including splenocyte producing inflammatory cytokines and T cell proliferation except for IL-1β and IL-2. Our findings indicate the possibility that dietary ISE attenuates ALI induced by BLM through correcting the inflammation and oxidation balance at least in part via inhibiting NF-κB signal in vivo, suggesting that ISE might be a valuable medicinal food effective in improving lung injury.
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http://dx.doi.org/10.1016/j.lfs.2019.05.074DOI Listing
August 2019

Plasmonic-enhanced catalytic activity of methanol oxidation on Au-graphene-Cu nanosandwiches.

Nanoscale 2019 May;11(18):8812-8824

State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China.

The plasmonic-enhanced catalytic activity of methanol oxidation on Au-based catalysts provides a promising strategy for direct methanol fuel cells (DMFCs) to avoid the CO poisoning of traditional Pt-based catalysts. However, the effect of surface plasmon resonance on the light-enhanced methanol oxidation activity of Au or Au-based catalysts has not been fully understood. The mechanism by which hot plasmonic carriers participate in the methanol oxidation reaction (MOR) has not been elucidated. Herein, Au nanoparticles (Au NPs) are loaded on a support of single-layer graphene-Cu contacts (SG/Cu) to construct a nanosandwich structure of a Au-graphene-Cu catalytic electrode (Au-n/SG/Cu). The Au-6T/SG/Cu catalytic electrode exhibits an MOR catalytic activity of approximately 288 μA μg-1 under simulated solar light irradiation, which is approximately 1.7 times higher than that without irradiation. The chemisorption capacity of OH- anions is enhanced on the Au-6T/SG/Cu catalytic electrode compared with the pure Au NP surface. The adsorbed OH- anions are oxidised into ˙OH radicals by the trapped positive holes on the Au NP surface. These OH radicals possessed a high oxidation capacity for the direct oxidation of HCOO- intermediates and promoted the complete methanol oxidation on Au NPs, which is beneficial for improving the fuel efficiency of DMFCs.
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http://dx.doi.org/10.1039/c9nr00361dDOI Listing
May 2019

DeepVID: Deep Visual Interpretation and Diagnosis for Image Classifiers via Knowledge Distillation.

IEEE Trans Vis Comput Graph 2019 Jun 15;25(6):2168-2180. Epub 2019 Mar 15.

Deep Neural Networks (DNNs) have been extensively used in multiple disciplines due to their superior performance. However, in most cases, DNNs are considered as black-boxes and the interpretation of their internal working mechanism is usually challenging. Given that model trust is often built on the understanding of how a model works, the interpretation of DNNs becomes more important, especially in safety-critical applications (e.g., medical diagnosis, autonomous driving). In this paper, we propose DeepVID, a Deep learning approach to Visually Interpret and Diagnose DNN models, especially image classifiers. In detail, we train a small locally-faithful model to mimic the behavior of an original cumbersome DNN around a particular data instance of interest, and the local model is sufficiently simple such that it can be visually interpreted (e.g., a linear model). Knowledge distillation is used to transfer the knowledge from the cumbersome DNN to the small model, and a deep generative model (i.e., variational auto-encoder) is used to generate neighbors around the instance of interest. Those neighbors, which come with small feature variances and semantic meanings, can effectively probe the DNN's behaviors around the interested instance and help the small model to learn those behaviors. Through comprehensive evaluations, as well as case studies conducted together with deep learning experts, we validate the effectiveness of DeepVID.
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http://dx.doi.org/10.1109/TVCG.2019.2903943DOI Listing
June 2019

Polyphenols Attenuate Inflammatory Response Via Modulating the Crosstalk Between Macrophages and Adipocytes.

Front Immunol 2019 26;10:286. Epub 2019 Feb 26.

Institute of Infection and Immunity of Huaihe Hospital, Henan University, Kaifeng, China.

Obesity is characterized as a chronic state of low-grade inflammation with progressive immune cell infiltration into adipose tissue. Adipose tissue macrophages play a critical role in the establishment of chronic inflammatory states and metabolic dysfunctions. (.) and extract polyphenols exhibit anti-carcinogenesis, anti-inflammatory, and anti-oxidant activities. However, the action of polyphenols in obesity-related inflammation has not been reported. The aim of this study was to explore the anti-inflammatory action of polyphenols from extract (ISE) in macrophages and the interaction between macrophages and adipocytes. RAW264.7 macrophages were stimulated with LPS or conditioned medium of hypertrophied 3T3-L1 adipocytes or cocultured with differentiated adipocytes in the presence of different doses of ISE. The inflammatory cytokines were evaluated by ELISA, the MAPK, NF-κB, and IL-6/STAT3 signals were determined by immunoblotting, and the migrated function of macrophages was determined by migration assay. ISE suppressed the inflammatory mediators including NO, TNF-α, IL-6, and MCP-1 induced by either LPS or conditioned medium derived from 3T3-L1 adipocytes. ISE also decreased the production of these inflammatory mediators in cocultures of 3T3-L1 adipocytes and RAW264.7 macrophages. Furthermore, ISE blocked RAW264.7 macrophages migration toward 3T3-L1 adipocytes in cocultures. Finally, this effect of ISE might be mediated via inhibiting ERK, p38, and STAT3 activation. Our findings indicate the possibility that ISE suppresses the interaction between macrophages and adipocytes, attenuates chronic inflammation in adipose tissue and improves obesity-related insulin resistance and complication, suggesting that ISE might be a valuable medicinal food effective in improving insulin resistance and metabolic syndrome.
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http://dx.doi.org/10.3389/fimmu.2019.00286DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6399398PMC
September 2020

Novel Construction of Morphology-Tunable C-N/SnO/ZnO/Au Microspheres with Ultrasensitivity and High Selectivity for Triethylamine under Various Temperature Detections.

ACS Appl Mater Interfaces 2019 Feb 13;11(8):8601-8611. Epub 2019 Feb 13.

School of Material Science and Engineering , University of Jinan , 250022 Jinan , P. R. China.

Morphology-tunable C-N/SnO-based hierarchical microspheres with good gas sensitivity for triethylamine (TEA) have been fabricated via facile electrospinning and a subsequent calcination process. The reaction temperature and modifying calcining technology played a dominant role for the morphological evolution from precursor fibers to microspherical shapes and the formation of C-N-decorated SnO phase composition. C-N/SnO/ZnO composites with tunable crystallinity, microstructure, and gas-sensing performance were strictly dependent on the added amount of Zn element. Fascinatingly, the constructed C-N/SnO/ZnO/Au composites can not only precisely regulate the crystal size, dispersion status, loading position, and content of Au nanoparticles but also display excellent gas-sensing properties with ultrasensitivity and high selectivity under various temperature detections. The response of C-N/SnO/ZnO/Au composites can reach up to approximately 1970, calculated to be 121.6 and 23.6 times for 50 ppm TEA molecules at optimal conditions compared with C-N/SnO and C-N/SnO/ZnO microspheres, respectively, actually representing the highest response value at high temperatures reported to date. The superior long-aging stability of sensing behaviors and phase structures can be also observed after 1 month. More importantly, novel C-N/SnO/ZnO/Au sensors were employed for availably detecting low-concentration volatiles released from the storage procedure of fishes at 80 °C, indicating the practical application in chemical detectors and biosensors at low temperature. The novel gas-sensing mechanisms derived primarily from the combination of phase compositions, morphologies, and unique surface/interface transfer processes of C-N/SnO/ZnO/Au composites are presented and investigated in detail, which will contribute to the design and development of other semiconductor-based composite sensors.
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http://dx.doi.org/10.1021/acsami.8b22357DOI Listing
February 2019