Publications by authors named "Jia Xu"

941 Publications

Deep learning for diagnosing osteonecrosis of the femoral head based on magnetic resonance imaging.

Comput Methods Programs Biomed 2021 Jun 5;208:106229. Epub 2021 Jun 5.

Longwood Valley Medical Technology Co. Ltd, China.

Background And Objective: Early-stage osteonecrosis of the femoral head (ONFH) can be difficult to detect because of a lack of symptoms. Magnetic resonance imaging (MRI) is sufficiently sensitive to detect ONFH; however, the diagnosis of ONFH requires experience and is time consuming. We developed a fully automatic deep learning model for detecting early-stage ONFH lesions on MRI.

Methods: This was a single-center retrospective study. Between January 2016 and December 2019, 298 patients underwent MRI and were diagnosed with ONFH. Of these patients, 110 with early-stage ONFH were included. Using a 7:3 ratio, we randomly divided them into training and testing datasets. All 3640 segments were delineated as the ground truth definition. The diagnostic performance of our model was analyzed using the receiver operating characteristic curve with the area under the receiver operating characteristic curve (AUC) and Hausdorff distance (HD). Differences in the area between the prediction and ground truth definition were assessed using the Pearson correlation and Bland-Altman plot.

Results: Our model's AUC was 0.97 with a mean sensitivity of 0.95 (0.95, 0.96) and specificity of 0.97 (0.96, 0.97). Our model's prediction had similar results with the ground truth definition with an average HD of 1.491 and correlation coefficient (r) of 0.84. The bias of the Bland-Altman analyses was 1.4 px (-117.7-120.5 px).

Conclusions: Our model could detect early-stage ONFH lesions in less time than the experts. However, future multicenter studies with larger data are required to further verify and improve our model.
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http://dx.doi.org/10.1016/j.cmpb.2021.106229DOI Listing
June 2021

Identification of the Main Active Components and Mechanism of Wang Bi Tablet in Treating Rheumatoid Arthritis Based on Integrative Pharmacology.

Front Pharmacol 2021 4;12:669551. Epub 2021 Jun 4.

Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China.

Wang Bi tablet (WBT) is used to treat rheumatoid arthritis (RA) in China. We employed integrative pharmacology, including rapid analysis of chemical composition, pharmacological experiment, and network pharmacology analysis, to elucidate the active components and mechanism underlying the effect of WBT against RA. The chemical fingerprint of WBT was revealed by UPLC-QTOF-MS/MS, and the chemical composition was identified. The anti-inflammatory effect of WBT was evaluated in TNF-α-stimulated RAW264.7 cells by ELISA and transcriptome sequencing. Network pharmacology analysis, functional enrichment analysis, and network visualization were performed. A total of 293 chemical constituents were preliminarily identified or tentatively characterized in WBT extract, and they effectively inhibited inflammatory response in TNF-α-stimulated RAW264.7 cells. Forty-eight key active constituents were identified based on high-frequency binding to hub targets and their corresponding targets number. Next, 135 corresponding hub genes, which may be the putative targets of WBT in treating RA, were selected. Functionally, the putative targets were significantly associated with the inflammatory immune response regulation module, energy metabolism regulation module, and cell function regulation module, corresponding to the traditional efficacy of WBT. In summary, this study revealed, for the first time using integrative pharmacology, that WBT may attenuate RA through the inflammation-immune regulation system.
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http://dx.doi.org/10.3389/fphar.2021.669551DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8213436PMC
June 2021

Prevalence and associated factors of psychological distress in tuberculosis patients in Northeast China: a cross-sectional study.

BMC Infect Dis 2021 Jun 12;21(1):563. Epub 2021 Jun 12.

School of Public Health, Dalian Medical University, 9 Western Section, Lvshun South Street, Lvshunkou District, Dalian, 116044, Liaoning, China.

Background: Psychological distress, a major comorbidities of tuberculosis (TB) patients, has posed a serious threat to the progress being made in global TB programs by affecting treatment adherence and health outcomes. However, the magnitude and associated factors of psychological distress have not been fully studied in China. The aim of the current study was to assess the prevalence of psychological distress in TB patients and to further determine the effects of socio-demographic characteristics, health-related variables, substance use status, social support, and experienced stigma on psychological distress.

Methods: A cross-sectional survey was conducted among TB patients attending three medical institutions in Dalian, Liaoning Province, Northeast China from November 2020 to March 2021. A structured questionnaire was developed to collect data on patients' socio-demographic characteristics, health-related information, substance use status, psychological distress, family function, doctor-patient relationship, policy support, experienced stigma and so on. The binary logistics regression model was used to determine the associated factors of psychological distress.

Results: A total of 473 TB patients were enrolled in this study, and the prevalence of psychological distress was 64.1%. Binary logistic regression analysis revealed that patients with a middle school education level or above (OR: 0.521, 95%CI: 0.279-0.974), no adverse drug reactions (OR: 0.476, 95%CI: 0.268-0.846), and regular physical exercise (OR: 0.528, 95%CI: 0.281-0.993) were more likely to stay away from psychological distress. However, patients who had a high economic burden (OR: 1.697, 95%CI: 1.014-2.840), diabetes (OR: 2.165, 95%CI: 1.025-4.573), self-rated illness severe (OR: 3.169, 95%CI: 1.081-9.285), perceived poor resistance (OR: 2.065, 95%CI: 1.118-3.815), severe family dysfunction (OR: 4.001, 95%CI: 1.158-13.823), perceived need for strengthen psychological counseling (OR: 4.837, 95%CI: 2.833-8.258), and a high experienced stigma (OR: 3.253, 95%CI: 1.966-5.384) tended to have a psychological distress.

Conclusions: The study found that the proportion of psychological distress among TB patients was high in Northeast China, and it was influenced by a variety of factors. Effective interventions to reduce psychological distress in TB patients urgently need to be developed, and greater attention should be given to patients with risk factors.
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http://dx.doi.org/10.1186/s12879-021-06284-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8196916PMC
June 2021

Local Structures of Soft Carbon and Electrochemical Performance of Potassium-Ion Batteries.

ACS Appl Mater Interfaces 2021 Jun 9. Epub 2021 Jun 9.

State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.

Due to climate variation and global warming, utilization of renewable energy becomes increasingly imperative. Rechargeable potassium-ion batteries (PIBs) have lately attracted much attention due to their earth-abundance and cost-effectiveness. Because soft carbon materials are cheap, abundant, and safe, extensive feasible research studies have indicated that they could become promising anode materials for PIBs. In spite of gaining achievements, fundamental questions regarding effects of the basic structure unit inside soft carbon on potassium storage potential have not been sufficiently addressed yet. Here, a series of soft carbon pyrolyzed from 900 to 2900 °C were systematically and quantitatively characterized by combining Raman spectroscopy, near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, X-ray pair distribution function analysis, and advanced evaluation of wide-angle X-ray scattering data. All these characterizations reveal structural details of soft carbon with increasing pyrolysis temperature. Our results show that the potassium storage behavior, especially the potential plateau is closely correlated to non-uniformity in interlayer distance and defect concentration in soft carbon, which is further confirmed by reverse Monte Carlo (RMC) modeling and density functional theory calculation. On the basis of these results, optimizing strategies are discussed to design an advanced soft carbon anode. This work provides significant insights into the structure engineering of soft carbon for high-performance rechargeable PIBs.
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http://dx.doi.org/10.1021/acsami.1c06303DOI Listing
June 2021

Application of Metagenomic Next-Generation Sequencing to Diagnose Pneumocystis jirovecii Pneumonia in Kidney Transplantation Recipients.

Ann Transplant 2021 Jun 8;26:e931059. Epub 2021 Jun 8.

Kidney Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China (mainland).

BACKGROUND Pneumocystis jirovecii pneumonia (PJP) is one of the common opportunistic infections diagnosed in kidney transplantation recipients. It is difficult to identify early by use of classic tools such as Grocott-Gomori stains and polymerase chain reaction (PCR). Metagenomic next-generation sequencing (mNGS) is accurate, unbiased, and sensitive, and is promising in PJP diagnosis. MATERIAL AND METHODS Data on kidney transplantation patients diagnosed with PJP were retrospectively analyzed. The sensitivity and specificity of different tools such as mNGS, laboratory tests, and Grocott-Gomori stains for PJP diagnosis were compared. All recipients were treated with trimethoprim-sulfamethoxazole (TMP-SMX). RESULTS There were a total of 12 kidney transplantation recipients diagnosed with PJP based on mNGS in our center from January 01, 2020 to October 27, 2020. Highly variable numbers of sequence reads for P. jiroveci (19 to 1041285) showed diagnostic significance. Bronchoalveolar lavage fluid (BALF) samples were tested by Grocott-Gomori staining, with only 6 of 11 (54.5%) positive. Other routine laboratory tests like routine blood tests, blood biochemistry, procalcitonin (PCT), immune function, (1,3)-ß-d-glucan (BG), serum galactomannan (GM), and C-reactive protein (CRP) showed even lower efficacy. TMP-SMX appeared to be the ideal therapy for kidney transplantation recipients with PJP. CONCLUSIONS mNGS has utility in the diagnosis of PJP and mixed infections in kidney transplantation recipients, and TMP-SMX could be the ideal therapeutic drug for kidney transplantation recipients suffering from PJP.
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http://dx.doi.org/10.12659/AOT.931059DOI Listing
June 2021

The poultry pathogen Riemerella anatipestifer appears as a reservoir for Tet(X) tigecycline resistance.

Environ Microbiol 2021 Jun 7. Epub 2021 Jun 7.

Department of Pathogen Biology & Microbiology and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, China.

The transferability of bacterial resistance to tigecycline, the 'last-resort' antibiotic, is an emerging challenge of global health concern. The plasmid-borne tet(X) that encodes a flavin-dependent monooxygenase represents a new mechanism for tigecycline resistance. Natural source for an ongoing family of Tet(X) resistance determinants is poorly understood. Here, we report the discovery of 26 new variants [tet(X18) to tet(X44)] from the poultry pathogen Riemerella anatipestifer, which expands extensively the current Tet(X) family. R. anatipestifer appears as a natural reservoir for tet(X), of which the chromosome harbours varied copies of tet(X) progenitors. Despite that an inactive ancestor rarely occurs, the action and mechanism of Tet(X2/4)-P, a putative Tet(X) progenitor, was comprehensively characterized, giving an intermediate level of tigecycline resistance. The potential pattern of Tet(X) dissemination from ducks to other animals and humans was raised, in the viewpoint of ecological niches. Therefore, this finding defines a large pool of natural sources for Tet(X) tigecycline resistance, heightening the need of efficient approaches to manage the inter-species transmission of tet(X) resistance determinants.
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http://dx.doi.org/10.1111/1462-2920.15632DOI Listing
June 2021

Diagnostic Biomarker Hsa_circ_0126218 and Functioning Prediction in Peripheral Blood Monocular Cells of Female Patients With Major Depressive Disorder.

Front Cell Dev Biol 2021 20;9:651803. Epub 2021 May 20.

Psychology and Health Management Center, Harbin Medical University, Harbin, China.

Introduction: Although major depressive diroder (MDD) has brought huge burden and challenges to society globally, effective and accurate diagnoses and treatments remain inadequate. The pathogenesis that for women are more likely to suffer from depression than men needs to be excavated as well. The function of circRNAs in pathological process of depression has not been widely investigated. This study aims to explore potential diagnostic biomarker circRNA of female patients with MDD and to investigate its role in pathogenesis.

Methods: First, an expression profile of circRNAs in the peripheral blood monocular cells of MDD patients and healthy peripherals were established based on high-throughput sequencing analysis. In addition, the top 10 differentially expressed circRNAs were quantified by quantitative real-time PCR to explore diagnostic biomarkers. To further investigate the function of biomarkers in the pathogenesis of MDD, bioinformatics analysis on downstream target genes of the biomarkers was carried out.

Results: There is a mass of dysregulated circRNAs in PBMCs between female MDD patients and healthy controls. Among the top 10 differentially expressed circRNAs, hsa_circ_0126218 is more feasible as a diagnostic biomarker. The expression level of hsa_circ_0126218 displayed upregulation in patients with MDD and the area under the operating characteristic curve of hsa_circ_0126218 was 0.801 (95% CI 0.7226-0.8791, < 0.0001). To explain the competing endogenous RNA role of hsa_circ_0126218 in the pathogenesis of female MDD, a hsa_circ_0126218-miRNA-mRNA network was established. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses stated that some of the enriched pathways downstream of hsa_circ_0126218 are closely related to MDD. Moreover, we established a protein-protein network to further screen out the hub genes (PIK3CA, PTEN, MAPK1, CDC42, Lyn, YES1, EPHB2, SMAD2, STAT1, and ILK). The function of hsa_circ_0126218 was refined by constructing a verified circRNA-predicted miRNA-hub gene subnetwork.

Conclusion: hsa_circ_0126218 can be considered as a new female MDD biomarker, and the pathogenesis of female MDD by the downstream regulation of hsa_circ_0126218 has been predicted. These findings may help further improve the early detection, effective diagnosis, convenient monitoring of complications, precise treatment, and timely recurrence prevention of depression.
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http://dx.doi.org/10.3389/fcell.2021.651803DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8174117PMC
May 2021

Andrographolide attenuates synovial inflammation of osteoarthritis by interacting with tumor necrosis factor receptor 2 trafficking in a rat model.

J Orthop Translat 2021 Jul 24;29:89-99. Epub 2021 May 24.

State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, PR China.

Background: Synovial inflammation plays a major role in the pathogenesis of osteoarthritis (OA). This study investigated the effect of andrographolide (Andro) on synovial inflammation mediated by tumor necrosis factor-alpha receptor 2 (TNFR2) trafficking and its utility in attenuating OA progression.

Methods: Knee joints were harvested from rats subjected to radial transection of the medial collateral ligament (MCLT) and medial meniscus (MMT) to examine the effect of Andro on synovial inflammation and OA progression. Quantitative real-time polymerase chain reaction was used to evaluate the expression of inflammatory factors in primary fibroblast-like synoviocytes (FLSs) after Andro treatment . The mechanism underlying Andro-mediated regulation of TNFR2 distribution and nuclear factor-κB (NF-κB) expression was verified using endosome maturation inhibitor hydroxychloroquine (HCQ) through flow cytometry, immunofluorescence, and western blot analysis.

Results: Andro treatment was found to reduce synovial inflammation and OA progression . Furthermore, a decrease in pain hypersensitivity and dorsal horn neuron activation was observed after treatment. Andro also downregulated the expression of inflammatory mediators and TNFR2 in FLSs. TNFR2 is crucial for the activation of the NF-κB signaling pathway, and Andro-induced degradation of TNFR2 was associated with lysosomal function, which in turn, reduced the downstream phosphorylation of p65 in the NF-κB signaling pathway.

Conclusions: Andro could suppress synovial inflammation via regulation of TNFR2 trafficking and degradation. This also suggests it could be a potential treatment for the prevention of synovial inflammation and OA progression.

The Translational Potential Of This Article: This study provides strong evidence that Andro reduces NF-κB activation and inflammatory responses in OA FLSs via regulation of TNFR2 trafficking. The inhibition of TNFR2 and Andro could be a novel therapeutic approach for OA and pain management.
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http://dx.doi.org/10.1016/j.jot.2021.05.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8144533PMC
July 2021

Wrinkled [email protected] magnetic composite microspheres: Regulation of magnetic content and their microwave absorbing performance.

J Colloid Interface Sci 2021 May 27;601:397-410. Epub 2021 May 27.

School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an 710072, China; Xi'an Key Laboratory of Functional Organic Porous Materials, Northwestern Polytechnical University, Xi'an 710129, China. Electronic address:

In this work, we develop a novel synthetic strategy for wrinkled magnetic composite microspheres ([email protected]). Firstly, hydrophobic oleic acid modified FeO (OA-FeO) nanoparticles acted as the magnetic component are prepared by synchronous modification coprecipitation method. The macromolecular emulsifier with initiating activity is obtained by means of soap-free emulsion polymerization under the presence of 1,1-diphenylethylene (DPE). Then, interfacial polymerization is employed to synthesis [email protected] ester/divinylbenzene composite microspheres ([email protected]/DVB). [email protected] composite microspheres are obtained by vacuum carbonization of the microspheres. The effect of magnetic content on the microwave absorbing properties of [email protected] composite microspheres is explored. The results show that [email protected] composite microspheres exhibit the excellent application performance at the FeO content of 0.15 g. The reflection loss can reach -53.7 dB at only thickness of 1.7 mm. The Maximum effective absorption bandwidth is up to 5.26 GHz with a thickness of 1.9 mm. The microwave attenuation mechanism of [email protected] composite microspheres is revealed. The excellent absorbing performance is attributed to the enhanced interfacial polarization ability, the surface wrinkled structure and the good synergy between dielectric and magnetic losses. This work provides an effective strategy for the design and preparation of new magnetic composite materials.
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http://dx.doi.org/10.1016/j.jcis.2021.05.153DOI Listing
May 2021

Correction to: lncRNA MEG3, Acting as a ceRNA, Modulates RPE Differentiation Through the miR-7-5p/Pax6 Axis.

Biochem Genet 2021 Jun 1. Epub 2021 Jun 1.

School of Public Health, Hangzhou Medical College, No. 182, Tianmushan Road, Hangzhou, 310013, Zhejiang, People's Republic of China.

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http://dx.doi.org/10.1007/s10528-021-10086-3DOI Listing
June 2021

Coastal Wetland Classification with GF-3 Polarimetric SAR Imagery by Using Object-Oriented Random Forest Algorithm.

Sensors (Basel) 2021 May 13;21(10). Epub 2021 May 13.

Jiangsu Provincial Hydraulic Research Institute, Nanjing 210017, China.

When the use of optical images is not practical due to cloud cover, Synthetic Aperture Radar (SAR) imagery is a preferred alternative for monitoring coastal wetlands because it is unaffected by weather conditions. Polarimetric SAR (PolSAR) enables the detection of different backscattering mechanisms and thus has potential applications in land cover classification. Gaofen-3 (GF-3) is the first Chinese civilian satellite with multi-polarized C-band SAR imaging capability. Coastal wetland classification with GF-3 polarimetric SAR imagery has attracted increased attention in recent years, but it remains challenging. The aim of this study was to classify land cover in coastal wetlands using an object-oriented random forest algorithm on the basis of GF-3 polarimetric SAR imagery. First, a set of 16 commonly used SAR features was extracted. Second, the importance of each SAR feature was calculated, and the optimal polarimetric features were selected for wetland classification by combining random forest (RF) with sequential backward selection (SBS). Finally, the proposed algorithm was utilized to classify different land cover types in the Yancheng Coastal Wetlands. The results show that the most important parameters for wetland classification in this study were Shannon entropy, Span and orientation randomness, combined with features derived from Yamaguchi decomposition, namely, volume scattering, double scattering, surface scattering and helix scattering. When the object-oriented RF classification approach was used with the optimal feature combination, different land cover types in the study area were classified, with an overall accuracy of up to 92%.
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http://dx.doi.org/10.3390/s21103395DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8152759PMC
May 2021

Learning by Distillation: A Self-Supervised Learning Framework for Optical Flow Estimation.

IEEE Trans Pattern Anal Mach Intell 2021 Jun 1;PP. Epub 2021 Jun 1.

We present DistillFlow, a knowledge distillation approach to learning optical flow. DistillFlow trains multiple teacher models and a student model, where challenging transformations are applied to the input of the student model to generate hallucinated occlusions as well as less confident predictions. Then, a self-supervised learning framework is constructed: confident predictions from teacher models are served as annotations to guide the student model to learn optical flow for those less confident predictions. The self-supervised learning framework enables us to effectively learn optical flow from unlabeled data, not only for non-occluded pixels, but also for occluded pixels. DistillFlow achieves state-of-the-art unsupervised learning performance on both KITTI and Sintel datasets. Our self-supervised pre-trained model also provides an excellent initialization for supervised fine-tuning, suggesting an alternate training paradigm in contrast to current supervised learning methods that highly rely on pre-training on synthetic data. At the time of writing, our fine-tuned models ranked 1st among all monocular methods on the KITTI 2015 benchmark, and outperform all published methods on the Sintel Final benchmark. More importantly, we demonstrate the generalization capability of DistillFlow in three aspects: framework generalization, correspondence generalization and cross-dataset generalization.
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http://dx.doi.org/10.1109/TPAMI.2021.3085525DOI Listing
June 2021

Efficacy of the "Eiffel tower" double titanium elastic nailing in combined management of congenital pseudarthrosis of the tibia: preliminary outcomes of 17 cases with review of literature.

BMC Musculoskelet Disord 2021 May 28;22(1):490. Epub 2021 May 28.

Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, China.

Background: Difficulty in obtaining union, recurrent fractures, and residual deformities remain the problems challenging the management of congenital pseudarthrosis of the tibia (CPT). We applied the "Eiffel Tower" double titanium elastic nails (TENs) in the existing combined approach, which takes advantages of TEN's mechanical stability with the protection against refracture, Ilizarov's high fusion rate with alignment control and the biologic environment provided by bone grafting for bony union. The results of this procedure are presented and discussed.

Methods: Seventeen patients with CPT treated by combined surgery including pseudarthrosis resection, the "Eiffel Tower" double TENs technique, autogenous iliac bone grafting, and Ilizarov fixation between 2013 and 2019 were retrospectively investigated. Signs of bone union, limb length discrepancy (LLD), rate of refracture, and degree of residual deformities were reviewed. The AOFAS Ankle Hindfoot scale and measurement of ankle motion were used to evaluate ankle function. The mean follow-up time was 40.5 (11 to 91) months.

Results: The mean age at index surgery was 6.2 (2.5 to 15) years. Union of the pseudarthrosis was achieved in 100% of cases. Among them, 15 (88.2%) patients obtained union of the pseudarthrosis on the first attempt (primary union). The average time to primary union was 3.8 (2 to 6) months. The rest 2 cases achieved union after additional surgeries (secondary union). In terms of complications, refracture occurred in 2 patients (11.8%) and 4 patients (23.5%) developed pin infection. The mean limb length discrepancy at the final follow up was 33.4 (6-141) mm. The average AOFAS score improved from 38.2 (27 to 51) pre-operatively to 77 (63 to 87) post-operatively (p < 0.01).

Conclusions: The "Eiffel Tower" double TENs technique is an ideal intramedullary fixation method in the surgical treatment of CPT. The combination of TENs technique with bone grafting and Ilizarov fixation has the advantages of early bone union, less injury on metaphysis, and early functional recovery.

Level Of Evidence: Level IV.
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http://dx.doi.org/10.1186/s12891-021-04382-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8162002PMC
May 2021

Selective Imaging of HClO in the Liver Tissue In Vivo Using a Near-infrared Hepatocyte-specific Fluorescent Probe.

Chem Asian J 2021 May 25. Epub 2021 May 25.

Key Laboratory of Medicinal Chemistry and Molecular Diagnosis (Ministry of Education), Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental Science, Hebei University, Wusi Dong Road 18, Baoding, 071002, P. R. China.

Liver injury is typified by an inflammatory response. Hypochlorous acid (HClO), an important endogenous reactive oxygen species, is regarded as a biomarker associated with liver injury. Near-infrared (NIR) fluorescent probes with the advantage of deep tissue penetrating and low auto-fluorescence interference are more suitable for bioimaging in vivo. Thus, in this work, we designed and synthesized a novel NIR hepatocyte-specific fluorescent probe named NHF. The probe NHF showed fast response (<3 s), large spectral variation, and good selectivity to trace HClO in buffer solution. By employing N-acetylgalactosamine (GalNAc) as the targeting ligand, probe NHF can be actively delivered to the liver tissue of zebrafish and mice. It is important that probe NHF is the first NIR hepatocyte-specific fluorescent probe, which successfully visualized the up-regulation of endogenous HClO in the oxygen-glucose deprivation/reperfusion (OGD/R) model HepG2 cells and dynamically monitored APAP-induced endogenous HClO in the liver tissue of zebrafish and mice.
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http://dx.doi.org/10.1002/asia.202100476DOI Listing
May 2021

lncRNA MEG3, Acting as a ceRNA, Modulates RPE Differentiation Through the miR-7-5p/Pax6 Axis.

Biochem Genet 2021 May 20. Epub 2021 May 20.

School of Public Health, Hangzhou Medical College, No. 182, Tianmushan Road, Hangzhou, 310013, Zhejiang, People's Republic of China.

Accumulated evidence indicated that long non-coding RNAs (lncRNAs) involves in numerous biological and pathological processes, including age-related macular degeneration (AMD). Dysfunction and dedifferentiation of retinal pigment epithelium (RPE) cells have been demonstrated to be one of the crucial factor in AMD etiology. Herein, we aim to investigate the essential role of lncRNA maternally expressed gene 3 (MEG3) in AMD progression. Expression patterns of MEG3 were measured in dysfunctional REP cells exposed with HO or TNF-α using qRT-PCR assay. Specifically, the intercellular distribution of MEG3 in REP cells was further explored using the subcellular fraction detection. Relative expression of RPE markers or RPE dedifferentiation-related markers was determined using qRT-PCR and western blot analysis, respectively. Immunofluorescence staining was performed to examine the expressions of RPE markers ZO-1 and β-catenin. Concentration of vascular endothelial growth factor (VEGFA) in the supernatant was detected using ELISA kit. Luciferase reporter assay was performed to verify the MEG3/miR-7-5p/Pax6 regulatory network, which was further determined in in vitro studies. MEG3 expression was significantly decreased in HO or TNF-α-treated REP cells, and it was upregulated along with RPE differentiation. Reduced MEG3 expression resulted in RPE dedifferentiation, which was indicated by decreased expressions of RPE markers, accumulated mitochondrial reactive oxygen species, and reduced VEGFA. Mechanistically, MEG3 functioned as a sponge for miR-7-5p to restore the expression of Pax6. Our study demonstrated that MEG3 exerts a protective role against AMD by maintaining RPE differentiation via miR-7-5p/Pax6 axis, suggesting a protective therapeutic target in AMD treatment.
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http://dx.doi.org/10.1007/s10528-021-10072-9DOI Listing
May 2021

Protective effects of recombinant 53-kDa protein of on acute lung injury in mice via alleviating lung pyroptosis by promoting M2 macrophage polarization.

Innate Immun 2021 May 20;27(4):313-323. Epub 2021 May 20.

Emergency Department, The First Affiliated Hospital of Sun Yat-sen University, No.58, Zhongshan 2nd Road, 510080, Guangzhou, China.

represents an effective treatment for autoimmune and inflammatory diseases. The effects of recombinant (TS) 53-kDa protein (rTsP53) on acute lung injury (ALI) remain unclear. Here, mice were divided randomly into a control group, LPS group, and rTsP53 + LPS group. ALI was induced in BALB/c mice by LPS (10 mg/kg) injected via the tail vein. rTsP53 (200 µl; 0.4 μg/μl) was injected subcutaneously three times at an interval of 5 d before inducing ALI in the rTsP53+LPS group. Lung pathological score, the ratio and markers of classic activated macrophages (M1) and alternatively activated macrophages (M2), cytokine profiles in alveolar lavage fluid, and pyroptosis protein expression in lung tissue were investigated. RTsP53 decreased lung pathological score. Furthermore, rTsP53 suppressed inflammation by increasing IL-4, IL-10, and IL-13. There was an increase in alveolar M2 macrophage numbers, with an increase in CD206 and arginase-1-positive cells and a decrease in alveolar M1 markers such as CD197 and iNOS. In addition, the polarization of M2 macrophages induced by rTsP53 treatment could alleviate ALI by suppressing lung pyroptosis. RTsP53 was identified as a potential agent for treating LPS-induced ALI via alleviating lung pyroptosis by promoting M2 macrophage polarization.
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http://dx.doi.org/10.1177/17534259211013397DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8186157PMC
May 2021

TRPV1 alleviates osteoarthritis by inhibiting M1 macrophage polarization via Ca/CaMKII/Nrf2 signaling pathway.

Cell Death Dis 2021 May 18;12(6):504. Epub 2021 May 18.

State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, People's Republic of China.

Osteoarthritis (OA) is the major course of joint deterioration, in which M1 macrophage-driven synovitis exacerbates the pathological process. However, precise therapies for M1 macrophage to decrease synovitis and attenuate OA progression have been scarcely proposed. Transient receptor potential vanilloid 1 (TRPV1) is a cation channel that has been implicated in pain perception and inflammation. In this study, we investigated the role of TRPV1 in the M1 macrophage polarization and pathogenesis of OA. We demonstrated that TRPV1 expression and M1 macrophage infiltration were simultaneously increased in both human and rat OA synovium. More than 90% of the infiltrated M1 macrophages expressed TRPV1. In the rat OA model, intra-articular injection of capsaicin (CPS), a specific TRPV1 agonist, significantly attenuated OA phenotypes, including joint swelling, synovitis, cartilage damage, and osteophyte formation. CPS treatment markedly reduced M1 macrophage infiltration in the synovium. Further mechanistic analyses showed that TRPV1-evoked Ca influx promoted the phosphorylation of calcium/calmodulin-dependent protein kinase II (CaMKII) and facilitated the nuclear localization of nuclear factor-erythroid 2-related factor 2 (Nrf2), which ultimately resulted in the inhibition of M1 macrophage polarization. Taken together, our findings establish that TRPV1 attenuates the progression of OA by inhibiting M1 macrophage polarization in synovium via the Ca/CaMKII/Nrf2 signaling pathway. These results highlight the effect of targeting TRPV1 for the development of a promising therapeutic strategy for OA.
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http://dx.doi.org/10.1038/s41419-021-03792-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8131608PMC
May 2021

Vasoactive Intestinal Peptide Promotes Fracture Healing in Sympathectomized Mice.

Calcif Tissue Int 2021 May 17. Epub 2021 May 17.

MOE Key Laboratory for Regenerative Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong SAR, People's Republic of China.

Vasoactive intestinal peptide (VIP) as a neuromodulator and neurotransmitter played a significant role in modulating bone homeostasis. Our previous study reported an essential role of VIP in in vitro BMSCs osteogenesis and in vivo bone defect repair. VIP was also revealed to have a promoting effect on embryonic skeletal element development. However, the role of VIP in fracture healing is not known yet. We hypothesized that the disorder of sympathetic nervous system impairs bone structure and fracture healing, whereas VIP may rescue the sympathetic inhibition effects and promote fracture healing. We employed a 6-hydroxydopamine (6-OHDA) induced sympathectomy mice model (sympathectomized mice), in which successful sympathetic inhibition was confirmed by a decreased level of norephedrine (NE) in the spleen. In the sympathectomized mice, the femoral micro-architecture, bone density and mechanical properties were all impaired compared to the vehicle control mice. The femoral fracture was created in the vehicle or sympathectomized mice. Vehicle mice were locally injected with PBS as a negative control, and the sympathectomized mice were treated with injection of PBS or VIP. VIP expression at the fracture site was significantly decreased in sympathectomized mice. The fracture healing was repressed upon 6-OHDA treatment and rescued by VIP treatment. Micro-CT examination showed that the femoral bone micro-architecture at the fracture sites and mechanical properties were all impaired. Simultaneously, the expression level of osteogenic markers OCN and OPN were reduced in sympathectomized mice compared with vehicle group. While the VIP treatment rescued the repression effects of 6-OHDA on bone remodeling and significantly promoted bone quality and mechanical properties as well as increased osteogenesis marker expression in the sympathectomized mice. VIP administration promoted bone fracture healing by inhibiting bone resorption, making it a putative new alternative treatment strategy for fracture healing.
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http://dx.doi.org/10.1007/s00223-021-00820-9DOI Listing
May 2021

Accelerated Bone Regeneration by Astragaloside IV through Stimulating the Coupling of Osteogenesis and Angiogenesis.

Int J Biol Sci 2021 24;17(7):1821-1836. Epub 2021 Apr 24.

Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, PR China.

Both osteoblasts and preosteoclasts contribute to the coupling of osteogenesis and angiogenesis, regulating bone regeneration. Astragaloside IV (AS-IV), a glycoside of cycloartane-type triterpene derived from the Chinese herb , exhibits various biological activities, including stimulating angiogenesis and attenuating ischemic-hypoxic injury. However, the effects and underlying mechanisms of AS-IV in osteogenesis, osteoclastogenesis, and bone regeneration remain poorly understood. In the present study, we found that AS-IV treatment inhibited osteoclastogenesis, preserved preosteoclasts, and enhanced platelet-derived growth factor-BB (PDGF-BB)-induced angiogenesis. Additionally, AS-IV promoted cell viability, osteogenic differentiation, and angiogenic gene expression in bone marrow mesenchymal stem cells (BMSCs). The activation of AKT/GSK-3β/β-catenin signaling was found to contribute to the effects of AS-IV on osteoclastogenesis and osteogenesis. Furthermore, AS-IV accelerated bone regeneration during distraction osteogenesis (DO), as evidenced from the improved radiological and histological manifestations and biomechanical parameters, accompanied by enhanced angiogenesis within the distraction zone. In summary, AS-IV accelerates bone regeneration during DO, by enhancing osteogenesis and preosteoclast-induced angiogenesis simultaneously, partially through AKT/GSK-3β/β-catenin signaling. These findings reveal that AS-IV may serve as a potential bioactive molecule for promoting the coupling of osteogenesis and angiogenesis, and imply that AKT/GSK-3β/β-catenin signaling may be a promising therapeutic target for patients during DO treatment.
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http://dx.doi.org/10.7150/ijbs.57681DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8120474PMC
April 2021

MiRNA-3662 reverses the gemcitabine resistance in pancreatic cancer through regulating the tumor metabolism.

Cancer Chemother Pharmacol 2021 May 15. Epub 2021 May 15.

Department of Gastrointestinal Surgery, The First People's Hospital of Yueyang, Yueyang, 414000, People's Republic of China.

Objectives: Gemcitabine (Gem) is one of the most commonly used chemotherapeutic drugs in treating patients with pancreatic ductal adenocarcinoma (PDAC). Acquired drug resistance against Gem presents a major clinical challenge in the chemotherapy of PDAC. It has been shown that miRNA-3662 is lowly expressed and implicated with quantities of biological processes in cancer. However, whether miRNA-3662 regulates chemoresistance in PDAC remains largely unknown.

Materials And Methods: The level of miRNA-3662 in PDAC tissues was determined by real-time qPCR (RT-qPCR). Functional experiments were used to investigate the biological role of miRNA-3662 on Gem resistance of PDAC in vitro and in vivo. Fluorescence in situ hybridization (FISH), RT-qPCR, western blotting, bioinformatics analysis and luciferase reporter assay were employed to determine the precise regulation mechanisms.

Results: In this study, it was investigated that miRNA-3662 was down-regulated in PDAC clinical samples as well as cell lines. Functional assays revealed that miRNA-3662 was sufficient to inhibit Gem resistance in PDAC cells both in vitro and in vivo. Mechanistically, hypoxia-inducible factor 1ɑ (HIF-1ɑ) was one of the transcriptional target of miRNA-3662 and was up-regulated in PDAC samples. Importantly, genetic promoting of HIF-1ɑ largely compromised miR-3662-mediated chemosensitive effects. In addition, miR-3662 could impair the aerobic glycolysis in PDAC cells.

Conclusions: This study sheds light on miRNA-3662 inhibits PDAC cell chemoresistance and aerobic glycolysis through a negative feedback loop with HIF-1ɑ. Therefore, the co-delivery of miR-3662 and Gem could be served as a promising therapeutic regimen for PDAC patients.
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http://dx.doi.org/10.1007/s00280-021-04289-zDOI Listing
May 2021

Adrenomedullin 2 improves bone regeneration in type 1 diabetic rats by restoring imbalanced macrophage polarization and impaired osteogenesis.

Stem Cell Res Ther 2021 May 13;12(1):288. Epub 2021 May 13.

Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, People's Republic of China.

Background: Both advanced glycation end products (AGEs) and AGE-mediated M1 macrophage polarization contribute to bone marrow mesenchymal stem cell (BMSC) dysfunction, leading to impaired bone regeneration in type 1 diabetes mellitus (T1DM). Adrenomedullin 2 (ADM2), an endogenous bioactive peptide belonging to the calcitonin gene-related peptide family, exhibits various biological activities associated with the inhibition of inflammation and reduction of insulin resistance. However, the effects and underlying mechanisms of ADM2 in AGE-induced macrophage M1 polarization, BMSC dysfunction, and impaired bone regeneration remain poorly understood.

Methods: The polarization of bone marrow-derived macrophages was verified using flow cytometry analysis. Alkaline phosphatase (ALP) staining, ALP activity detection, and alizarin red staining were performed to assess the osteogenesis of BMSCs. Quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting, and immunofluorescence staining were used to assess polarization markers, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, and osteogenic markers. In vivo, a distraction osteogenesis (DO) rat model with T1DM was established, and tibia samples were collected at different time points for radiological, biomechanical, and histological analyses, to verify the effects of ADM2 on bone regeneration and M2 polarization under diabetic conditions.

Results: ADM2 treatment reversed AGE-induced M1 macrophage polarization towards the M2 phenotype, which was partially achieved by the peroxisome proliferator-activated receptor γ (PPARγ)-mediated inhibition of NF-κB signaling. The PPARγ inhibitor GW9662 significantly attenuated the effects of ADM2. Besides, ADM2 treatment improved the AGE-impaired osteogenic potential of BMSCs in vitro. Furthermore, ADM2 accelerated bone regeneration, as revealed by improved radiological and histological manifestations and biomechanical parameters, accompanied by improved M2 macrophage polarization in diabetic DO rats, and these effects were partially blocked by GW9662 administration.

Conclusions: These results indicate that ADM2 enhances diabetic bone regeneration during DO, by attenuating AGE-induced imbalances in macrophage polarization, partly through PPARγ/NF-κB signaling, and improving AGE-impaired osteogenic differentiation of BMSCs simultaneously. These findings reveal that ADM2 may serve as a potential bioactive factor for promoting bone regeneration under diabetic conditions, and imply that management of inflammation and osteogenesis, in parallel, may present a promising therapeutic strategy for diabetic patients during DO treatment.
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http://dx.doi.org/10.1186/s13287-021-02368-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8117361PMC
May 2021

Highly Permeable Polyamide Nanofiltration Membrane Mediated by an Upscalable Wet-Laid EVOH Nanofibrous Scaffold.

ACS Appl Mater Interfaces 2021 May 7;13(19):23142-23152. Epub 2021 May 7.

Key Laboratory of Textile Fiber and Products, Ministry of Education, Hubei International Scientific and Technological Cooperation Base of Intelligent Textile Materials & Application, Wuhan Textile University, Wuhan 430200, China.

For energy-saving purposes, the pursuit of ultrahigh permeance nanofiltration membranes without sacrificing selectivity is never-ending in desalination, wastewater treatment, and industrial product separation. Herein, we reported a novel facile route to engineer a highly porous and superhydrophilic nanofibrous substrate to mediate the interfacial polymerization between trimesoyl chloride and piperazine, generating an ultrathin PA active layer (∼13 nm) with a hierarchical crumpled surface. The wet laying process and subsequent plasma treatment endowed a rougher and more hydrophilic surface for ethylene vinyl alcohol copolymer (EVOH) nanofibers in the thin compact nanofibrous scaffold (∼9 μm) with a mean pore size of 210 nm, radically different from the nanofibrous membrane by other methods. Nanofibrous scaffold with these features provide abundant thin-thick alternative continuous water layers between nanofibers and organic phase, facilitating the formation of the abovementioned PA layer. As a result, an ultrahigh permeance of 42.25 L·m h bar and a reasonably high rejection of 95.97% to 1000 ppm NaSO feed solution were obtained, superior to most state-of-the-art NF membranes reported so far. Our work provides an easy and scalable method to fabricate advanced PA NF membranes with outstanding performance, highlighting its great potential in liquid separation.
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http://dx.doi.org/10.1021/acsami.1c02776DOI Listing
May 2021

Biodegradability of Micro/Nanomotors: Challenges and Opportunities.

Adv Healthc Mater 2021 May 6:e2100335. Epub 2021 May 6.

School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Screening, Southern Medical University, Guangzhou, 510515, China.

Micro/nanomotors (MNMs) are miniature machines that can convert chemical or external energy into their own mechanical motions. In previous decades, significant efforts have been made to improve the performance of MNMs. For practical applications, the biodegradability of MNMs is an important aspect that must be considered, particularly in the biomedical field. In this review, recent progress in the biodegradability of MNMs and their potential applications are summarized. Different biodegradable materials, including metals and polymers, or other strategies for the fabrication of MNMs, are presented. Current challenges and future perspectives are also discussed.
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http://dx.doi.org/10.1002/adhm.202100335DOI Listing
May 2021

Accelerated Bone Regeneration by Adrenomedullin 2 Through Improving the Coupling of Osteogenesis and Angiogenesis via β-Catenin Signaling.

Front Cell Dev Biol 2021 14;9:649277. Epub 2021 Apr 14.

Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.

Both osteogenic differentiation and the pro-angiogenic potential of bone marrow mesenchymal stem cells (BMSCs) contribute to bone regeneration during distraction osteogenesis (DO). Adrenomedullin 2 (ADM2), an endogenous bioactive peptide belonging to the calcitonin gene-related peptide family, exhibits various biological activities associated with the inhibition of inflammation and the attenuation of ischemic-hypoxic injury. However, the effects and underlying mechanisms of ADM2 in osteogenic differentiation and the pro-angiogenic potential of BMSCs, along with bone regeneration, remain poorly understood. In the present study, we found that osteogenic induction enhanced the pro-angiogenic potential of BMSCs, and ADM2 treatment further improved the osteogenic differentiation and pro-angiogenic potential of BMSCs. Moreover, the accumulation and activation of β-catenin, which is mediated by the inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and the activation of protein kinase B (AKT), have been shown to contribute to the effects of ADM2 on BMSCs. , ADM2 accelerated vessel expansion and bone regeneration, as revealed by improved radiological and histological manifestations and the biomechanical parameters in a rat DO model. Based on the present results, we concluded that ADM2 accelerates bone regeneration during DO by enhancing the osteogenic differentiation and pro-angiogenic potential of BMSCs, partly through the NF-κB/β-catenin and AKT/β-catenin pathways. Moreover, these findings imply that BMSC-mediated coupling of osteogenesis and angiogenesis may be a promising therapeutic strategy for DO patients.
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http://dx.doi.org/10.3389/fcell.2021.649277DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8079771PMC
April 2021

Severe Acute Respiratory Syndrome Coronavirus 2 and Male Reproduction: Relationship, Explanations, and Clinical Remedies.

Front Physiol 2021 14;12:651408. Epub 2021 Apr 14.

Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Coronavirus disease 2019 (COVID-2019) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been an ongoing pandemic and worldwide public health emergency, having drawn a lot of attention around the world. The pathogenesis of COVID-19 is characterized by infecting angiotensin-converting enzyme 2 (ACE2)-expressing cells, including testis-specific cells, namely, Leydig, Sertoli, and spermatogenic cells, which are closely related to male reproduction. This leads to aberrant hyperactivation of the immune system generating damage to the infected organs. An impairment in testicular function through uncontrolled immune responses alerts more attention to male infertility. Meanwhile, the recent clinical data indicate that the infection of the human testis with SARS-CoV-2 may impair male germ cell development, leading to germ cell loss and higher immune cell infiltration. In this review, we investigated the evidence of male reproductive dysfunction associated with the infection with SARS-CoV-2 and its possible immunological explanations and clinical remedies.
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http://dx.doi.org/10.3389/fphys.2021.651408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8079781PMC
April 2021

Evolution of isoprene emission in Arecaceae (palms).

Evol Appl 2021 Apr 14;14(4):902-914. Epub 2020 Dec 14.

Department of Biodiversity and Molecular Ecology, Research and Innovation Centre Fondazione Edmund Mach San Michele all'Adige Italy.

Isoprene synthase (IspS) is the sole enzyme in plants responsible for the yearly emission in the atmosphere of thousands of tonnes of the natural hydrocarbon isoprene worldwide. Species of the monocotyledonous family Arecaceae (palms) are among the highest plant emitters, but to date no gene from this family has been identified. Here, we screened with PTR-ToF-MS 18 genera of the Arecaceae for isoprene emission and found that the majority of the sampled species emits isoprene. Putative genes from six different genera were sequenced and three of them were functionally characterized by heterologous overexpression in , demonstrating that they encode functional IspS genes. Site-directed mutagenesis and expression in Arabidopsis demonstrated the functional relevance of a novel IspS diagnostic tetrad from Arecaceae, whose most variable amino acids could not preserve catalytic function when substituted by a putatively dicotyledonous-specific tetrad. In particular, mutation of threonine 479 likely impairs the open-closed transition of the enzyme by altering the network of hydrogen bonds between helices H1α, H, and I. These results shed new light on the evolution of IspS in monocots, suggesting that isoprene emission is an ancestral trait within the Arecaceae family. The identification of IspS from Arecaceae provides promising novel enzymes for the production of isoprene in heterologous systems and allows the screening and selection of commercially relevant palm varieties with lower environmental impact.
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http://dx.doi.org/10.1111/eva.13169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8061277PMC
April 2021

Continuous-flow electrosynthesis of selenium-substituted iminoisobenzofuran via oxidative cyclization of olefinic amides and diselenides.

Org Biomol Chem 2021 Apr 24;19(14):3207-3212. Epub 2021 Mar 24.

College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhu Rd S., Nanjing 211816, China. and State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, 30 Puzhu Rd S., Nanjing 211816, China.

A green and efficient approach for the synthesis of selenium-substituted iminoisobenzofuran using 2-vinylbenzamides and diselenides in a continuous electrochemical microreactor has been developed. This strategy enabled the preparation of a series of iminoisobenzofuran derivatives in moderate to good yields under metal-free and oxidant-free conditions. The application of the electrochemical flow system successfully overcomes the difficulty of process control in traditional electrochemistry and achieves efficient transformation of electricity. Moreover, the continuous-flow system combined with electrosynthesis overcomes the difficulty in realizing a scale-up reaction in conventional batch-type electrolysis.
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http://dx.doi.org/10.1039/d1ob00236hDOI Listing
April 2021

Temporal-spatial features and key factors' analysis of vertical eddy diffusivities in Taihu Lake, China.

Environ Sci Pollut Res Int 2021 Apr 18. Epub 2021 Apr 18.

School of Hydrology and Water Resources, Nanjing University of Information Science and Technology, 219 Ningliu Rd, Nanjing, 210044, China.

Vertical eddy diffusivity (VED) is used to quantify the vertical mixing of water column, which has a profound influence on the evolution of aquatic ecosystems. Based on half-hourly water temperature measured at -20 cm and -150 cm depths from 2015 to 2017 at stations of Pingtaishan (PTS), Dapukou (DPK), Bifenggang (BFG), and Xiaoleishan (XLS) in Taihu Lake, the daily average VED is calculated according to the phase lag of water temperature series at two depths. The temporal and spatial features and possible evolution characters of vertical turbulences are then deliberated. The results show that the VED in Taihu Lake varies by several orders of magnitude. The weak VED exhibits stronger spatial heterogeneity and high frequency characteristics and vice versa for the strong VED. The VED in the center region of the lake is stronger, in comparison to bay areas. On seasonality, the VED is the strongest in winter, moderate in spring and autumn, and the weakest in summer. Analyses show that solar radiation and wind forcing are the key meteorological factors regulating VED changes, with the solar effect somewhat stronger than wind. It is also discussed potential roles of vertical mixing in cyanobacteria becoming dominant population in Taihu Lake.
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http://dx.doi.org/10.1007/s11356-021-13810-zDOI Listing
April 2021

Factors associated with a SARS-CoV-2 recurrence after hospital discharge among patients with COVID-19: systematic review and meta-analysis.

J Zhejiang Univ Sci B 2020 Dec.;21(12):940-947

State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.

Background: The proportion of recurrences after discharge among patients with coronavirus disease 2019 (COVID-19) was reported to be between 9.1% and 31.0%. Little is known about this issue, however, so we performed a meta-analysis to summarize the demographical, clinical, and laboratorial characteristics of non-recurrence and recurrence groups.

Methods: Comprehensive searches were conducted using eight electronic databases. Data regarding the demographic, clinical, and laboratorial characteristics of both recurrence and non-recurrence groups were extracted, and quantitative and qualitative analyses were conducted.

Results: Ten studies involving 2071 COVID-19 cases were included in this analysis. The proportion of recurrence cases involving patients with COVID-19 was 17.65% (between 12.38% and 25.16%) while older patients were more likely to experience recurrence (weighted mean difference (WMD)=1.67, range between 0.08 and 3.26). The time from discharge to recurrence was 13.38 d (between 12.08 and 14.69 d). Patients were categorized as having moderate severity (odds ratio (OR)=2.69, range between 1.30 and 5.58), while those with clinical symptoms including cough (OR=5.52, range between 3.18 and 9.60), sputum production (OR=5.10, range between 2.60 and 9.97), headache (OR=3.57, range between 1.36 and 9.35), and dizziness (OR=3.17, range between 1.12 and 8.96) were more likely to be associated with recurrence. Patients presenting with bilateral pulmonary infiltration and decreased leucocyte, platelet, and CD4 T counts were at risk of COVID-19 recurrence (OR=1.71, range between 1.07 and 2.75; WMD=-1.06, range between -1.55 and -0.57, WMD=-40.39, range between -80.20 and -0.48, and WMD=-55.26, range between -105.92 and -4.60, respectively).

Conclusions: The main factors associated with the recurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after hospital discharge were older age, moderate severity, bilateral pulmonary infiltration, laboratory findings including decreased leucocytes, platelets, and CD4 T counts, and clinical symptoms including cough, sputum production, headache, and dizziness. These factors can be considered warning indicators for the recurrence of SARS-CoV-2 and might help the development of specific management strategies.
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http://dx.doi.org/10.1631/jzus.B2000304DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7759453PMC
April 2021

Melatonin alleviates lipopolysaccharide-induced myocardial injury by inhibiting inflammation and pyroptosis in cardiomyocytes.

Ann Transl Med 2021 Mar;9(5):413

Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, School of Medicine, South China University of Technology, Guangzhou, China.

Background: Melatonin (MT) has been shown to protect against various cardiovascular diseases. However, the effect of MT on lipopolysaccharide (LPS)-induced myocardial injury is poorly understood. This study aims to evaluate the effects of MT on LPS-induced myocardial injury .

Methods: H9C2 cells were divided into a control group, MT group, LPS group, and MT + LPS group. The control group was treated with sterile saline solution, the LPS group received 8 µg/mL LPS for 24 h, MT + LPS cells were pretreated with 200 µmol/L MT for 2 h then with 8 µg/mL LPS for 24 h, and the MT group received only 200 µmol/L MT for 2 h. The CCK-8 assay and lactate dehydrogenase (LDH) activity assay were used to analyze cell viability and LDH release, respectively. Intracellular reactive oxygen species (ROS) and the rate of pyroptosis were measured using the fluorescent probe dichloro-dihydro-fluorescein diacetate (DCFH-DA) and propidium iodide (PI) staining, respectively. The cell supernatants were used to measure the levels of inflammatory cytokines, including IL-6, TNF-α, and IL-1β by enzyme-linked immunosorbent assay (ELISA). The protein levels of iNOS, COX-2, NF-κB, p-NF-κB, NLRP3, caspase-1, and GSDMD were detected by western blot.

Results: MT pretreatment significantly improved LPS-induced myocardial injury by inhibiting inflammation and pyroptosis in H9C2 cells. Moreover, MT inhibited the activation of the NF-κB pathway, and reduced the expression of inflammation-related proteins (iNOS and COX-2), and pyroptosis-related proteins (NLRP3, caspase-1, and GSDMD).

Conclusions: Our data suggests that MT can alleviate LPS-induced myocardial injury, providing novel insights into the treatment of sepsis-induced myocardial dysfunction.
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http://dx.doi.org/10.21037/atm-20-8196DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033388PMC
March 2021