Publications by authors named "Chao Zhou"

553 Publications

CTNNB1 S37C mutation causing cells proliferation and migration coupled with molecular mechanisms in lung adenocarcinoma.

Ann Transl Med 2021 Apr;9(8):681

Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China.

Background: This study aimed to investigate the potential cytological effects and molecular mechanisms of β-catenin (CTNNB1) S37C mutation in lung adenocarcinoma (LUAD).

Methods: CTNNB1 with S37C mutation were transfected into LUAD cell lines. The expression of β-catenin were determined using Western blot. Cell proliferation and migration were detected using cell counting kit-8 (CCK-8) assay and wound healing assay, respectively. Transcriptome sequencing was performed on LUAD cells with CTNNB1 S37C mutation (CTNNB1 mutation group) and LUAD cells without treatment (Control group), followed by the screening of differentially expressed genes (DEGs). Functional enrichment analysis and protein-protein interaction (PPI) analysis were performed for the DEGs. Finally, the expression of key DEGs were validated by quantitative real-time PCR (qRT-PCR).

Results: CTNNB1 with S37C mutation was successful expressed in 2 cell lines. Cells proliferation and migration were significantly promoted in mutation group in comparison with that of Control group (P<0.05). A total of 180 DEGs were revealed between Control and CTNNB1 mutation groups. These DEGs were mainly enriched in extracellular matrix function and nicotine addiction pathway. PPI network contained 51 DEGs and 45 interactions. PTPRD, GNG7 and CNTN1 were hub genes in PPI network with higher degree. CGB5 interacted with PTPRU, while IGFBP3 showed interaction with MMP1. Results of qRT-PCR confirmed the expression of several key DEGs in transcriptome analysis.

Conclusions: CTNNB1 S37C mutation contributed the LUAD cells proliferation and migration. PTPRD, IGFBP-3, MMP1 and PTPRU might play roles in the effect of CTNNB1 S37C mutation in LUAD.
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http://dx.doi.org/10.21037/atm-21-1146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8106026PMC
April 2021

Causal influences of neuroticism on mental health and cardiovascular disease.

Hum Genet 2021 May 11. Epub 2021 May 11.

Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Bio-X Institutes, Shanghai Jiao Tong University, Shanghai, 200030, China.

We investigated the relationship between neuroticism and 16 mental and 18 physical traits using summary results of genome-wide association studies for these traits. LD score regression was used to investigate genetic correlations between neuroticism and the 34 health outcomes. Mendelian randomization was performed to investigate mutual causal relationships between neuroticism and the 34 health outcomes. Neuroticism genetically correlates with a majority of health-related traits and confers causal effects on 12 mental traits (major depressive disorder (MDD), insomnia, subjective well-being (SWB, negatively), schizophrenia, attention-deficit/hyperactivity disorder, alcohol dependence, loneliness, anorexia nervosa, anxiety disorder, bipolar disorder, obsessive-compulsive disorder, and psychiatric disorders) and two physical diseases (cardiovascular disease and hypertensive disease). Conversely, MDD, SWB, and insomnia have a causal effect on neuroticism. We highlighted key genes contributing to the causal associations between neuroticism and MDD, including RBFOX1, RERE, SOX5, and TCF4, and those contributing to the causal associations between neuroticism and cardiovascular diseases, including MAD1L1, ARNTL, RERE, and SOX6. The present study indicates that genetic variation mediates the causal influences of neuroticism on mental health and cardiovascular diseases.
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http://dx.doi.org/10.1007/s00439-021-02288-xDOI Listing
May 2021

Tumor Mutation Burden and Immune Invasion Characteristics in Triple Negative Breast Cancer: Genome High-Throughput Data Analysis.

Front Immunol 2021 21;12:650491. Epub 2021 Apr 21.

Department of Oncology, Weifang Traditional Chinese Hospital, Weifang, China.

In recent years, the emergence of immunotherapy has provided a new perspective for the treatment and management of triple-negative breast cancer (TNBC). However, the relationship between tumor mutation burden (TMB) and immune infiltration and the prognosis of TNBC remains unclear. In this study, to explore the immunogenicity of TNBC, we divided patients with TNBC into high and low TMB groups based on the somatic mutation data of TNBC in The Cancer Genome Atlas (TCGA), and screened out genes with mutation rate ≥10. Then, Kaplan-Meier survival analysis revealed that the 5-year survival rate of the high TMB group was much higher than that of the low TMB group and the two groups also showed differences in immune cell infiltration. Further exploration found that the FAT3 gene, which displays significant difference and a higher mutation rate between the two groups, is not only significantly related to the prognosis of TNBC patients but also exhibits difference in immune cell infiltration between the wild group and the mutant group of the FAT3 gene. The results of gene set enrichment analysis and drug sensitivity analysis further support the importance of the FAT3 gene in TNBC. This study reveals the characteristics of TMB and immune cell infiltration in triple-negative breast cancer and their relationship with prognosis, to provide new biomarkers and potential treatment options for the future treatment of TNBC. The FAT3 gene, as a risk predictor gene of TNBC, is considered a potential biological target and may provide new insight for the treatment of TNBC.
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http://dx.doi.org/10.3389/fimmu.2021.650491DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8097167PMC
April 2021

Ultra-short time imaging of total-body PET/CT for cancer pain-induced untenable body position.

Eur J Nucl Med Mol Imaging 2021 May 8. Epub 2021 May 8.

Department of Nuclear Medicine, Sun Yat-Sen University Cancer Center, Sun Yat-Sen University, Guangzhou, 510030, Guangdong, China.

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http://dx.doi.org/10.1007/s00259-021-05380-6DOI Listing
May 2021

Effect of Counterion Binding to Swelling of Polyelectrolyte Brushes.

Langmuir 2021 May 3;37(18):5554-5562. Epub 2021 May 3.

Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

The effect of binding strength of counterions with the polyelectrolyte chain to the swelling of polyelectrolyte brushes is studied, by investigating the swelling of both the polycation and polyanion in response to the variation of the salt concentration under the change of counterion's identity. Two polyelectrolyte brushes grafted on solid substrates are adopted: the cationic poly [2-(methacryloyloxy)ethyltrimethyl ammonium] (PMETA-X, X = F, Cl, Br, and I) and the anionic polystyrene sulfonate (M-PSS, M = Li, Na, K, and Cs). The swelling change with the salt concentration is investigated by ellipsometry, quartz crystal microbalance with dissipation, and dielectric spectroscopy. It is discovered that although the thickness of PMETA-X brushes is larger than that of M-PSS brushes of similar grafting density, the former has much less solvent incorporated than the latter. Such a difference is attributed to the weaker interaction between the PMETA chain and its halide counterions than that between the PSS chain and its alkali counterions, discovered by dielectric spectroscopy. This makes the original charges on the PMETA-X chain less neutralized and therefore have a higher charge density, compared with the M-PSS chain. The results demonstrate that the stronger binding of the counterions to the polyelectrolytes makes the main chains less charged, resulting in the weaker inter-chain electrostatic repulsion and less swelling of the brushes. Investigations into the effect of ion identity show the following order of binding strength: for the cationic PMETA chain, F < Cl < Br < I and for the anionic PSS chain, Li < Na < K < Cs.
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http://dx.doi.org/10.1021/acs.langmuir.1c00309DOI Listing
May 2021

1800 MHz Radiofrequency Electromagnetic Field Impairs Neurite Outgrowth Through Inhibiting EPHA5 Signaling.

Front Cell Dev Biol 2021 12;9:657623. Epub 2021 Apr 12.

Department of Occupational Health, Third Military Medical University, Chongqing, China.

The increasing intensity of environmental radiofrequency electromagnetic fields (RF-EMF) has increased public concern about its health effects. Of particular concern are the influences of RF-EMF exposure on the development of the brain. The mechanisms of how RF-EMF acts on the developing brain are not fully understood. Here, based on high-throughput RNA sequencing techniques, we revealed that transcripts related to neurite development were significantly influenced by 1800 MHz RF-EMF exposure during neuronal differentiation. Exposure to RF-EMF remarkably decreased the total length of neurite and the number of branch points in neural stem cells-derived neurons and retinoic acid-induced Neuro-2A cells. The expression of Eph receptors 5 (EPHA5), which is required for neurite outgrowth, was inhibited remarkably after RF-EMF exposure. Enhancing EPHA5 signaling rescued the inhibitory effects of RF-EMF on neurite outgrowth. Besides, we identified that cAMP-response element-binding protein (CREB) and RhoA were critical downstream factors of EPHA5 signaling in mediating the inhibitory effects of RF-EMF on neurite outgrowth. Together, our finding revealed that RF-EMF exposure impaired neurite outgrowth through EPHA5 signaling. This finding explored the effects and key mechanisms of how RF-EMF exposure impaired neurite outgrowth and also provided a new clue to understanding the influences of RF-EMF on brain development.
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http://dx.doi.org/10.3389/fcell.2021.657623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8075058PMC
April 2021

Genetic deletion of endothelial microRNA-15a/16-1 promotes cerebral angiogenesis and neurological recovery in ischemic stroke through Src signaling pathway.

J Cereb Blood Flow Metab 2021 Apr 28:271678X211010351. Epub 2021 Apr 28.

Pittsburgh Institute of Brain Disorders and Recovery, Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.

Cerebral angiogenesis is tightly controlled by specific microRNAs (miRs), including the miR-15a/16-1 cluster. Recently, we reported that endothelium-specific conditional knockout of the miR-15a/16-1 cluster (EC-miR-15a/16-1 cKO) promotes post-stroke angiogenesis and improves long-term neurological recovery by increasing protein levels of VEGFA, FGF2, and their respective receptors VEGFR2 and FGFR1. Herein, we further investigated the underlying signaling mechanism of these pro-angiogenic factors after ischemic stroke using a selective Src family inhibitor AZD0530. EC-miR-15a/16-1 cKO and age- and sex-matched wild-type littermate (WT) mice were subjected to 1 h middle cerebral artery occlusion (MCAO) and 28d reperfusion. AZD0530 was administered daily by oral gavage to both genotypes of mice 3-21d after MCAO. Compared to WT, AZD0530 administration exacerbated spatial cognitive impairments and brain atrophy in EC-miR-15a/16-1 cKO mice following MCAO. AZD0530 also attenuated long-term recovery of blood flow and inhibited the formation of new microvessels, including functional vessels with blood circulation, in the penumbra of stroked cKO mice. Moreover, AZD0530 blocked the Src signaling pathway by downregulating phospho-Src and its downstream mediators (p-Stat3, p-Akt, p-FAK, p-p44/42 MAPK, p-p38 MAPK) in post-ischemic brains. Collectively, our data demonstrated that endothelium-targeted deletion of the miR-15a/16-1 cluster promotes post-stroke angiogenesis and improves long-term neurological recovery via activating Src signaling pathway.
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http://dx.doi.org/10.1177/0271678X211010351DOI Listing
April 2021

Composited FishNet: Fish Detection and Species Recognition From Low-Quality Underwater Videos.

IEEE Trans Image Process 2021 3;30:4719-4734. Epub 2021 May 3.

The automatic detection and identification of fish from underwater videos is of great significance for fishery resource assessment and ecological environment monitoring. However, due to the poor quality of underwater images and unconstrained fish movement, traditional hand-designed feature extraction methods or convolutional neural network (CNN)-based object detection algorithms cannot meet the detection requirements in real underwater scenes. Therefore, to realize fish recognition and localization in a complex underwater environment, this paper proposes a novel composite fish detection framework based on a composite backbone and an enhanced path aggregation network called Composited FishNet. By improving the residual network (ResNet), a new composite backbone network (CBresnet) is designed to learn the scene change information (source domain style), which is caused by the differences in the image brightness, fish orientation, seabed structure, aquatic plant movement, fish species shape and texture differences. Thus, the interference of underwater environmental information on the object characteristics is reduced, and the output of the main network to the object information is strengthened. In addition, to better integrate the high and low feature information output from CBresnet, the enhanced path aggregation network (EPANet) is also designed to solve the insufficient utilization of semantic information caused by linear upsampling. The experimental results show that the average precision (AP), AP and average recall (AR) of the proposed Composited FishNet are 75.2%, 92.8% and 81.1%, respectively. The composite backbone network enhances the characteristic information output of the detected object and improves the utilization of characteristic information. This method can be used for fish detection and identification in complex underwater environments such as oceans and aquaculture.
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http://dx.doi.org/10.1109/TIP.2021.3074738DOI Listing
May 2021

Mechanisms and functions of membrane lipid remodeling in plants.

Plant J 2021 Apr 14. Epub 2021 Apr 14.

Biology Department, Brookhaven National Laboratory, Upton, NY, 11973, USA.

Lipid remodeling, defined herein as post-synthetic structural modifications of membrane lipids, play crucial roles in regulating the physicochemical properties of cellular membranes and hence their many functions. Processes affected by lipid remodeling include lipid metabolism, membrane repair, cellular homeostasis, fatty acid trafficking, cellular signaling and stress tolerance. Glycerolipids are the major structural components of cellular membranes and their composition can be adjusted by modifying their head groups, their acyl chain lengths and the number and position of double bonds. This review summarizes recent advances in our understanding of mechanisms of membrane lipid remodeling with emphasis on the lipases and acyltransferases involved in the modification of phosphatidylcholine and monogalactosyldiacylglycerol, the major membrane lipids of extraplastidic and photosynthetic membranes, respectively. We also discuss the role of triacylglycerol metabolism in membrane acyl chain remodeling. Finally, we discuss emerging data concerning the functional roles of glycerolipid remodeling in plant stress responses. Illustrating the molecular basis of lipid remodeling may lead to novel strategies for crop improvement and other biotechnological applications such as bioenergy production.
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http://dx.doi.org/10.1111/tpj.15273DOI Listing
April 2021

Interleukin-28A maintains the intestinal epithelial barrier function through regulation of claudin-1.

Ann Transl Med 2021 Mar;9(5):365

Department of General Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China.

Background: Interleukin-28A (IL-28A or interferon-λ2) is reported to maintain intestinal mucosal homeostasis. However, the effects and mechanisms of IL-28A on intestinal ischemia reperfusion (I/R) have not yet been studied.

Methods: Adult C57BL/6 mice were randomly divided into three groups: sham, I/R, and I/R+IL-28A (n=5 in each group). The I/R+IL-28A group mice were injected with recombinant mouse IL-28A 12 hours before the operation. Mice were sacrificed 6 hours after reperfusion. The mucosal permeability was investigated, and histology analyses were performed. Additionally, a hypoxic Caco-2 cell culture model was established. Fludarabine was used to inhibit phosphorylated signal transducer and activator of transcription 1 (pSTAT1). The expression of IL-28A, tight junctions (TJs), and pSTAT1 was assessed by western blot, immunohistochemical (IHC) staining, or immunofluorescence staining. Epithelial permeability was measured by transepithelial electrical resistance (TER).

Results: The expression of IL-28A was decreased in intestinal lamina propria in the I/R group compared with the control group. Administration of IL-28A significantly alleviated the I/R-induced increase in intestinal permeability and tissue damage. Treatment with IL-28A significantly attenuated intestinal I/R-induced disruption of TJ proteins, including zonula occludens-1 (ZO-1), occludin, and claudin-1. , IL-28A treatment reversed the decrease in TER of Caco-2 monolayers exposed to hypoxic environments. IL-28A led to the activation of STAT1 and the upregulation of claudin-1 expression both and . Also, inhibiting phosphorylation of STAT1 reversed the effects of IL-28A on the expression and distribution of claudin-1 in Caco-2 cells.

Conclusions: Intestinal epithelial barrier dysfunction caused by intestinal I/R is ameliorated by IL-28A via the regulation of claudin-1.
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http://dx.doi.org/10.21037/atm-20-5494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033364PMC
March 2021

FLVCR1 Predicts Poor Prognosis and Promotes Malignant Phenotype in Esophageal Squamous Cell Carcinoma Upregulating CSE1L.

Front Oncol 2021 25;11:660955. Epub 2021 Mar 25.

Department of Gastroenterology, The Affiliated Taizhou Hospital, Wenzhou Medical University, Taizhou, China.

Objective: Dysregulation of feline leukemia virus subgroup C receptor 1(FLVCR1) expression has been investigated in several tumors. However, the expression and role of FLVCR1 in esophageal squamous cell carcinoma (ESCC) remain largely unknown.

Methods: FLVCR1 expression in tissues was measured by immunohistochemical staining (IHC). Celigo assay, MTT assay, colony formation, caspase 3/7 activity analysis, wound healing assay, Transwell migration, and invasion assay were applied to assess the effects of FLVCR1 on ESCC tumorigenesis. Coimmunoprecipitation (Co-IP) and liquid chromatography-mass spectrometry (LC-MS) were used to identify protein interactions with FLVCR1. An imaging system (IVIS) was used to investigate the functions of FLVCR1 on the growth and metastatic capability of ESCC cells in a xenograft model and a tail vein metastasis model.

Results: Elevated expression of FLVCR1 was detected in ESCC tissues and predicted poor survival. Upregulated FLVCR1 was positively correlated with lymph node metastasis (N stage) and late tumor-node-metastasis (TNM) stage. FLVCR1 knockdown inhibited cell proliferation and colony formation ability, induced cell apoptosis, and repressed cell migration and invasion of ESCC . Inhibition of FLVCR1 markedly repressed tumorigenicity and metastasis of ESCC cells . Mechanistically, chromosome segregation 1-like (CSE1L) was identified to interact with FLVCR1 using a Co-IP assay. Moreover, the inhibitory effect of FLVCR1 knockdown on proliferation and migration was counteracted by the exogenous expression of CSE1L.

Conclusion: FLVCR1 plays a pivotal role in ESCC cell survival, growth, and migration. These functions may be partially dependent upon the protein interaction between FLVCR1 and CSE1L. In addition, FLVCR1 can be applied as a clinical prognostic marker for patients with ESCC.
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http://dx.doi.org/10.3389/fonc.2021.660955DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8027484PMC
March 2021

Blood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease.

BMC Neurol 2021 Apr 9;21(1):154. Epub 2021 Apr 9.

Department of Neurology (Stroke Unit). Hospital de la Santa Creu i Sant Pau, Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.

Background: The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow.

Methods: Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol.

Results: After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [- 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001).

Conclusions: The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.
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http://dx.doi.org/10.1186/s12883-021-02179-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033703PMC
April 2021

The Impact of Collaboration Network on Water Resource Governance Performance: Evidence from China's Yangtze River Delta Region.

Int J Environ Res Public Health 2021 03 4;18(5). Epub 2021 Mar 4.

School of Government, Sun Yat-sen University, Guangzhou 510275, China.

Existing studies rarely examine the relationship between network structure and network performance. To fill this research gap, this article collects inter-local collaboration network data from 41 cities in the Yangtze River Delta region of China from 2009 to 2015. Based on the institutional collective action framework and social capital theory, we propose bridging and bonding hypotheses regarding the impact of network structures on governance performance. We employ social network analysis and panel data regression models to test the hypotheses. The results show that the coefficients for closeness centrality and clustering coefficient are statistically significant in this analysis, Wuxi played a central role in the collaboration network and the region had formed a close partner network, confirming the positive effect of bridging and bonding network social capital structures on network performance.
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http://dx.doi.org/10.3390/ijerph18052557DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7967326PMC
March 2021

Longitudinal dynamics of antibody responses in recovered COVID-19 patients.

Signal Transduct Target Ther 2021 03 31;6(1):137. Epub 2021 Mar 31.

Department of Virology, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, Beijing, China.

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http://dx.doi.org/10.1038/s41392-021-00559-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009921PMC
March 2021

Hyperphosphatemia and Cardiovascular Disease.

Front Cell Dev Biol 2021 4;9:644363. Epub 2021 Mar 4.

John Moorhead Research Laboratory, Centre for Nephrology, University College London (UCL) Medical School, London, United Kingdom.

Hyperphosphatemia or even serum phosphate levels within the "normal laboratory range" are highly associated with increased cardiovascular disease risk and mortality in the general population and patients suffering from chronic kidney disease (CKD). As the kidney function declines, serum phosphate levels rise and subsequently induce the development of hypertension, vascular calcification, cardiac valvular calcification, atherosclerosis, left ventricular hypertrophy and myocardial fibrosis by distinct mechanisms. Therefore, phosphate is considered as a promising therapeutic target to improve the cardiovascular outcome in CKD patients. The current therapeutic strategies are based on dietary and pharmacological reduction of serum phosphate levels to prevent hyperphosphatemia in CKD patients. Large randomized clinical trials with hard endpoints are urgently needed to establish a causal relationship between phosphate excess and cardiovascular disease (CVD) and to determine if lowering serum phosphate constitutes an effective intervention for the prevention and treatment of CVD.
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http://dx.doi.org/10.3389/fcell.2021.644363DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7970112PMC
March 2021

Corrigendum: CDKL3 Targets ATG5 to Promote Carcinogenesis of Esophageal Squamous Cell Carcinoma.

Front Oncol 2020 4;10:619438. Epub 2021 Mar 4.

Department of Gastroenterology, The Affiliated Taizhou Hospital, Wenzhou Medical University, Taizhou, China.

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http://dx.doi.org/10.3389/fonc.2020.619438DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7971111PMC
March 2021

Using C-acetate Pulse-chase Labeling to Study Fatty Acid and Glycerolipid Metabolism in Plant Leaves.

Bio Protoc 2021 Feb 5;11(3):e3900. Epub 2021 Feb 5.

Biology Department, Brookhaven National Laboratory, Upton, New York, USA.

Lipids metabolism is comprised of networks of reactions occurred in different subcellular compartments. Isotopic labeling is a good way to track the transformations and movements of metabolites without perturbing overall cellular metabolism. Fatty acids, the building blocks of membrane lipids and storage triacylglycerols, are synthesized in plastids. The immediate precursor for fatty acid synthesis is acetyl-CoA. Exogenous acetate is rapidly incorporated into fatty acids in leaves and isolated plastids because it can diffuse freely through cellular membranes, enter the plastid where it is rapidly metabolized to acetyl-CoA. Therefore, isotope-labeled acetate is often used as a tracer for the investigation of fatty acid synthesis and complex lipid metabolism in plants and other organisms. The basic principle of isotope labeling and its recent technological advances have been reviewed ( Allen , 2015 ). The present protocol describes the use of C-labeled acetate to determine rates of fatty acid synthesis and degradation and to track the metabolism of glycerolipids in leaves. This method, which is often referred to as acetate pulse-chase labeling, has been widely used to probe various aspects of lipid metabolism ( Allen , 2015 ), including the role of autophagy in membrane lipid turnover ( Fan , 2019 ) and the interplay between lipid and starch metabolism pathways ( Yu , 2018 ).
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http://dx.doi.org/10.21769/BioProtoc.3900DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7953248PMC
February 2021

Molecular classification and clinical diagnosis of acute-on-chronic liver failure patients by serum metabolomics.

J Pharm Biomed Anal 2021 May 6;198:114004. Epub 2021 Mar 6.

Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100193, China. Electronic address:

Prevalence of acute-on-chronic liver failure (ACLF) patients is growing worldwide, associating with multi-organ failure and high short-term mortality rates. ACLF can be of varying entity manifestation, whereas it remains poorly defined. Traditional Chinese medicine (TCM) stratifies ACLF into two types, damp hot (DH) and cold damp (CD), by seasoned TCM practitioners, for specific treatment with different TCMs. The biggest challenge for the outcome of TCM therapy is the accuracy of diagnosis. However, it is difficult to guarantee it due to lack of the molecule classification of ACLF. Herein, we recruited 58 subjects including 34 ACLF patients (18 DH and 16 CD) and 24 healthy controls, and analyzed serum metabolic profiles using untargeted ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) metabolomics approach. A total of 10 serum metabolites were found as potential biomarkers for diagnosis of ACLF. Among them, taurochenodesoxycholic acid (N3), glycyldeoxycholic acid (N5) and 12-HETE-GABA (N7), varied between two types of ACLF and can be merged as a combination marker to differentiate CD from DH patients with area under the receiver operating curve (AUC) of 0.928 (95 % CI 0.8-1). CD patients possessed comparatively higher bile acid metabolism and lower arachidonic acid metabolism compared with DH patients. The results provide not only serum molecules for early accurate diagnosis of ACLF patients, but also potential clinical biomarkers for classification of CD and DH types. The findings clarify that molecular markers will be objective criteria for diagnosis of clinical types in TCM practice.
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http://dx.doi.org/10.1016/j.jpba.2021.114004DOI Listing
May 2021

Clock dial integrated positioning combined with single utility port video-assisted thoracoscopic surgery: a new localization method for lung tumors.

J Thorac Dis 2021 Feb;13(2):1143-1150

Department of Cardiothoracic Surgery, Dehong People's Hospital, Affiliated Dehong People's Hospital of Kunming Medical University, Dehong, China.

Background: Preoperative localization of lung tumor mainly consisted of two methods: CT-guided percutaneous localization and electromagnetic navigation bronchoscopy-guided localization. However, these invasive methods could result in serious complications. In order to avoid the adverse effects of preoperative invasive localization, we propose a method of intraoperative noninvasive localization for lung tumors: clock dial integrated positioning (CDIP).

Methods: To retrospectively analyze the clinic data about the application of CDIP for 127 lung tumour patients in single utility port video-assisted thoracoscopic surgery (SUPVATS) between June 2017 and October 2017.

Results: One hundred and twenty-four cases (97.64%) underwent thoracoscopic surgery, which including 14 lobectomy, 107 partial resection, 2 lobectomy plus partial resection and 1 left pneumonectomy. Three cases (2.36%) underwent thoracoscopic biopsy. The mean operation time and intraoperative bleeding were 47.9±22.1 min and 70.1±40.3 mL, respectively. The mean postoperative hospital stay and chest drain duration were 3.9±2.2 and 3.6±1.8 days, respectively. There were 118 cases of malignant tumors, including adenocarcinoma (n=101), squamous cell carcinoma (n=9), large cell carcinoma (n=2), small cell lung carcinoma (n=3), and metastatic lung carcinoma (n=3). The remaining nine cases were benign tumors, including granuloma (n=3), intrapulmonary lymph node (n=2), sclerosing hemangioma (n=2), and hamartoma (n=2). The incidence of postoperative complications was 10.2%. There was no mortality, secondary operation, or conversion to open procedure due to massive intraoperative bleeding.

Conclusions: CDIP combined with SUPVATS is a safe, feasible, and effective method for the localization of lung tumors. This novel method can provide a reliable alternative technique when the marker is dislocated.
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http://dx.doi.org/10.21037/jtd-20-3312DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7947540PMC
February 2021

HIV Drug Resistance Mutations Detection by Next-Generation Sequencing during Antiretroviral Therapy Interruption in China.

Pathogens 2021 Feb 25;10(3). Epub 2021 Feb 25.

National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.

Patients with antiretroviral therapy interruption have a high risk of virological failure when re-initiating antiretroviral therapy (ART), especially those with HIV drug resistance. Next-generation sequencing may provide close scrutiny on their minority drug resistance variant. A cross-sectional study was conducted in patients with ART interruption in five regions in China in 2016. Through Sanger and next-generation sequencing in parallel, HIV drug resistance was genotyped on their plasma samples. Rates of HIV drug resistance were compared by the McNemar tests. In total, 174 patients were included in this study, with a median 12 (interquartile range (IQR), 6-24) months of ART interruption. Most (86.2%) of them had received efavirenz (EFV)/nevirapine (NVP)-based first-line therapy for a median 16 (IQR, 7-26) months before ART interruption. Sixty-one (35.1%) patients had CRF07_BC HIV-1 strains, 58 (33.3%) CRF08_BC and 35 (20.1%) CRF01_AE. Thirty-four (19.5%) of the 174 patients were detected to harbor HIV drug-resistant variants on Sanger sequencing. Thirty-six (20.7%), 37 (21.3%), 42 (24.1%), 79 (45.4%) and 139 (79.9) patients were identified to have HIV drug resistance by next-generation sequencing at 20% (v.s. Sanger, = 0.317), 10% (v.s. Sanger, = 0.180), 5% (v.s. Sanger, = 0.011), 2% (v.s. Sanger, < 0.001) and 1% (v.s. Sanger, < 0.001) of detection thresholds, respectively. K65R was the most common minority mutation, of 95.1% (58/61) and 93.1% (54/58) in CRF07_BC and CRF08_BC, respectively, when compared with 5.7% (2/35) in CRF01_AE ( < 0.001). In 49 patients that followed-up a median 10 months later, HIV drug resistance mutations at >20% frequency such as K103N, M184VI and P225H still existed, but with decreased frequencies. The prevalence of HIV drug resistance in ART interruption was higher than 15% in the survey. Next-generation sequencing was able to detect more minority drug resistance variants than Sanger. There was a sharp increase in minority drug resistance variants when the detection threshold was below 5%.
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http://dx.doi.org/10.3390/pathogens10030264DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996606PMC
February 2021

SDG711 Is Involved in Rice Seed Development through Regulation of Starch Metabolism Gene Expression in Coordination with Other Histone Modifications.

Rice (N Y) 2021 Mar 5;14(1):25. Epub 2021 Mar 5.

Key Laboratory of Three Gorges Regional Plant Genetics & Germplasm Enhancement (CTGU) /Biotechnology Research Center, China Three Gorges University, Yichang, 443002, China.

SDG711 is a histone H3K27me2/3 transmethylase in rice, a homolog of CLF in Arabidopsis, and plays key roles in regulating flowering time and panicle development. In this work, we investigated the role of SDG711 in rice seed development. Overexpression and downregulation of SDG711 lead to a decrease and increase in the expression level of genes related to starch accumulation, resulting in smaller seeds or even seed abortion. ChIP assay showed that SDG711-mediated H3K27me3 changed significantly in genes related to endosperm development, and SDG711 can directly bind to the gene body region of several starch synthesis genes and amylase genes. In addition, H3K4me3 and H3K9ac modifications also cooperate with H3K27me3 to regulate the development of the endosperm. Our results suggest that the crosstalk between SDG711-mediated H3K27me3 and H3K4me3, and H3K9ac are involved in starch accumulation to control normal seed development.
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http://dx.doi.org/10.1186/s12284-021-00467-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7936014PMC
March 2021

[Research Status and Hot Trends in Atherosclerosis Genomics between 2010 and 2019].

Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2021 Feb;43(1):92-100

Department of Vascular Surgery,the Affiliated Hospital of Shandong University of Chinese Medicine,Jinan 250011,China.

Objective To analyze the research status,hotspots,and frontiers of atherosclerosis genomics from 2010 to 2019.Methods CiteSpace software was used to conduct data statistics and visual analysis on countries,institutions,authors,journals,co-cited papers,and keywords of the related papers published in the Web of Science from 2010 to 2019.Results A total of 1021 papers in English were included,and the annual number of publications generally showed an upward trend.The knowledge base in the research of atherosclerosis mostly focused on the genetic risk sites and biomarkers for coronary artery diseases such as coronary heart disease,myocardial infarction,and dyslipidemia.The related journals mainly involved the fields of molecular biology,biology,genetics,immunology,medicine,pharmacy,and clinical medicine.The latest research in atherosclerosis concentrated on genome-wide association study,DNA methylation,microRNA,messenger RNA and so on.The research frontiers involved long noncoding RNA,DNA methylation,and immune metabolism.Conclusion The studies in atherosclerotic genomics have gradually increased.
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http://dx.doi.org/10.3881/j.issn.1000-503X.13266DOI Listing
February 2021

Adaptive intensity-modulated radiotherapy with simultaneous integrated boost for stage III non-small cell lung cancer: Is a routine adaptation beneficial?

Radiother Oncol 2021 May 23;158:118-124. Epub 2021 Feb 23.

Laboratory of Cellular and Molecular Radiation Oncology, Radiation Oncology Institute of Enze Medical Health Academy, Affiliated Taizhou Hospital of Wenzhou Medical University, China; Department of Radiation Oncology, Affiliated Taizhou Hospital of Wenzhou Medical University, China. Electronic address:

Purpose: Tumor and anatomical changes during radiotherapy have been observed in stage III non-small cell lung cancer (NSCLC) from many previous studies. We hypothesized that a routinely scheduled adaptive radiotherapy would have clinical important dose benefits to lower the risk of toxicities, without increasing the tumor recurrences.

Methods: We retrospectively reviewed 92 consecutive patients with inoperable stage III NSCLC between November 2017 and March 2019. All eligible patients should received simultaneously integrated boost (SIB) using intensity-modulated radiation therapy (IMRT). A mid-treatment CT simulation and a new adapted plan were routinely given after the first 20 fractions. The organs at risk (OARs) were delineated per RTOG 1106 atlas. Dose-volume histograms were quantitatively compared between the initial and composite adaptive plans. Logistic regression was applied to analyze the dose-response relationship. Clinical endpoints included acute symptomatic radiation pneumonitis (RP2) and esophagitis (RE2), local and regional tumor control, and progression-free survival (PFS).

Results: Sixty-four eligible patients received adaptive SIB-IMRT were consecutively included. The GTVs reduced by a median of -38.2% after 42 to 44 Gy in 20 fractions of radiotherapy. By adapting to tumor and anatomical changes, dosimetric parameters of OARs decreased significantly. The mean lung dose decreased by an average of -74.8 cGy, and mean esophagus dose was lower by 183.1 cGy. We found grade 2 or higher acute RP in 11 patients (17.2%), and RE2 in 28 patients (43.8%). Commonly used lung and esophagus dose metrics were significantly associated with RP2 and RE2. The adaptation could reduce RP2 probability by 3%, and RE2 risk by 5%. Subgroups with higher OARs dose or larger tumor shrinkage may get more dose and toxicities benefits. The estimated median PFS was 12.5 months from the start of radiotherapy.

Conclusions: We demonstrated that the routinely adaptive SIB-IMRT strategy could significantly reduce the dose to surrounding normal tissues, potentially lower the associated acute RP and RE, without increasing the risk of tumor recurrences.
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http://dx.doi.org/10.1016/j.radonc.2021.02.019DOI Listing
May 2021

Chloroplast lipid biosynthesis is fine-tuned to thylakoid membrane remodeling during light acclimation.

Plant Physiol 2021 Feb;185(1):94-107

Biology Department, Brookhaven National Laboratory, Upton, New York 11973, USA.

Reprogramming metabolism, in addition to modifying the structure and function of the photosynthetic machinery, is crucial for plant acclimation to changing light conditions. One of the key acclimatory responses involves reorganization of the photosynthetic membrane system including changes in thylakoid stacking. Glycerolipids are the main structural component of thylakoids and their synthesis involves two main pathways localized in the plastid and the endoplasmic reticulum (ER); however, the role of lipid metabolism in light acclimation remains poorly understood. We found that fatty acid synthesis, membrane lipid content, the plastid lipid biosynthetic pathway activity, and the degree of thylakoid stacking were significantly higher in plants grown under low light compared with plants grown under normal light. Plants grown under high light, on the other hand, showed a lower rate of fatty acid synthesis, a higher fatty acid flux through the ER pathway, higher triacylglycerol content, and thylakoid membrane unstacking. We additionally demonstrated that changes in rates of fatty acid synthesis under different growth light conditions are due to post-translational regulation of the plastidic acetyl-CoA carboxylase activity. Furthermore, Arabidopsis mutants defective in one of the two glycerolipid biosynthetic pathways displayed altered growth patterns and a severely reduced ability to remodel thylakoid architecture, particularly under high light. Overall, this study reveals how plants fine-tune fatty acid and glycerolipid biosynthesis to cellular metabolic needs in response to long-term changes in light conditions, highlighting the importance of lipid metabolism in light acclimation.
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http://dx.doi.org/10.1093/plphys/kiaa013DOI Listing
February 2021

Exploring the effect of virtual reality relaxation environment on white coat hypertension in blood pressure measurement.

J Biomed Inform 2021 Apr 22;116:103721. Epub 2021 Feb 22.

College of Software, Shandong University, Shandong, China. Electronic address:

A phenomenon called White Coat Hypertension (WCH) often occurs when measuring blood pressure (BP) in a real medical environment. Utilizing virtual reality (VR) technology to present appropriate relaxation scenes can isolate the real medical environments and may provide a new method to avoid WCH and improve the accuracy of BP measurement. In this study, we designed four immersive VR relaxation scenes and conducted an experiment to explore the role of VR scenes in eliminating/detecting WCH in BP measurement. Results from the current sample showed that both systolic BP and diastolic BP measured in the simulated medical environment were significantly higher than the baseline level and the VR scene condition, while there were no significant differences between the BPs measured in VR scenes and the baseline level. It can be concluded that VR provides an effective approach to avoid WCH in BP measurement by visually and aurally isolating the real environment and assisting relaxation and provides a new approach to detect the occurrence of WCH by the comparison of BPs measured in the VR scene condition and real medical environments.
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http://dx.doi.org/10.1016/j.jbi.2021.103721DOI Listing
April 2021

Hyperphosphatemia in chronic kidney disease exacerbates atherosclerosis via a mannosidases-mediated complex-type conversion of SCAP N-glycans.

Kidney Int 2021 Feb 23. Epub 2021 Feb 23.

John Moorhead Research Laboratory, Centre for Nephrology, University College London Medical School, Royal Free Campus, London, United Kingdom; Centre for Lipid Research and Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, the Second Affiliated Hospital, Chongqing Medical University, Chongqing, People's Republic of China. Electronic address:

Blood phosphate levels are linked to atherosclerotic cardiovascular disease in patients with chronic kidney disease (CKD), but the molecular mechanisms remain unclear. Emerging studies indicate an involvement of hyperphosphatemia in CKD accelerated atherogenesis through disturbed cholesterol homeostasis. Here, we investigated a potential atherogenic role of high phosphate concentrations acting through aberrant activation of sterol regulatory element-binding protein (SREBP) and cleavage-activating protein (SCAP)-SREBP2 signaling in patients with CKD, hyperphosphatemic apolipoprotein E (ApoE) knockout mice, and cultured vascular smooth muscle cells. Hyperphosphatemia correlated positively with increased atherosclerotic cardiovascular disease risk in Chinese patients with CKD and severe atheromatous lesions in the aortas of ApoE knockout mice. Mice arteries had elevated SCAP levels with aberrantly activated SCAP-SREBP2 signaling. Excess phosphate in vitro raised the activity of α-mannosidase, resulting in delayed SCAP degradation through promoting complex-type conversion of SCAP N-glycans. The retention of SCAP enhanced transactivation of SREBP2 and expression of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, boosting intracellular cholesterol synthesis. Elevated α-mannosidase II activity was also observed in the aortas of ApoE knockout mice and the radial arteries of patients with uremia and hyperphosphatemia. High phosphate concentration in vitro elevated α-mannosidase II activity in the Golgi, enhanced complex-type conversion of SCAP N-glycans, thereby upregulating intracellular cholesterol synthesis. Thus, our studies explain how hyperphosphatemia independently accelerates atherosclerosis in CKD.
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http://dx.doi.org/10.1016/j.kint.2021.01.016DOI Listing
February 2021

Fecal Microbiota Transplantation Is a Promising Method to Restore Gut Microbiota Dysbiosis and Relieve Neurological Deficits after Traumatic Brain Injury.

Oxid Med Cell Longev 2021 10;2021:5816837. Epub 2021 Feb 10.

Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.

Background: Traumatic brain injury (TBI) can induce persistent fluctuation in the gut microbiota makeup and abundance. The present study is aimed at determining whether fecal microbiota transplantation (FMT) can rescue microbiota changes and ameliorate neurological deficits after TBI in rats.

Methods: A controlled cortical impact (CCI) model was used to simulate TBI in male Sprague-Dawley rats, and FMT was performed for 7 consecutive days. 16S ribosomal RNA (rRNA) sequencing of fecal samples was performed to analyze the effects of FMT on gut microbiota. Modified neurological severity score and Morris water maze were used to evaluate neurobehavioral functions. Metabolomics was used to screen differential metabolites from the rat serum and ipsilateral brains. The oxidative stress indices were measured in the brain.

Results: TBI induced significance changes in the gut microbiome, including the alpha- and beta-bacterial diversity, as well as the microbiome composition at 8 days after TBI. On the other hand, FMT could rescue these changes and relieve neurological deficits after TBI. Metabolomics results showed that the level of trimethylamine (TMA) in feces and the level of trimethylamine N-oxide (TMAO) in the ipsilateral brain and serum was increased after TBI, while FMT decreased TMA levels in the feces, and TMAO levels in the ipsilateral brain and serum. Antioxidant enzyme methionine sulfoxide reductase A (MsrA) in the ipsilateral hippocampus was decreased after TBI but increased after FMT. In addition, FMT elevated SOD and CAT activities and GSH/GSSG ratio and diminished ROS, GSSG, and MDA levels in the ipsilateral hippocampus after TBI.

Conclusions: FMT can restore gut microbiota dysbiosis and relieve neurological deficits possibly through the TMA-TMAO-MsrA signaling pathway after TBI.
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http://dx.doi.org/10.1155/2021/5816837DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7894052PMC
February 2021

Systematic Review and Meta-Analysis of Antibiotic-Impregnated Shunt Catheters on Anti-Infective Effect of Hydrocephalus Shunt.

J Korean Neurosurg Soc 2021 Mar 29;64(2):297-308. Epub 2021 Jan 29.

National United Engineering Laboratory for Biomedical Material Modification, Branden Industrial Park, Dezhou, China.

Objective: Shunt infection is a common complication while treating hydrocephalus. The antibiotic-impregnated shunt catheter (AISC) was designed to reduce shunt infection rate. A meta-analysis was conducted to study the effectiveness of AISCs in reduction of shunt infection in terms of age, follow-up time and high-risk patient population.

Methods: This study reviewed literature from three databases including PubMed, EMBASE, and Cochrane Library (from 2000 to March 2019). Clinical studies from controlled trials for shunt operation were included in this analysis. A subgroup analysis was performed based on the patient's age, follow-up time and high-risk population. The fixed effect in RevMan 5.3 software (Cochrane Collaboration) was used for this meta-analysis.

Results: This study included 19 controlled clinical trials including 10105 operations. The analysis demonstrated that AISC could reduce the infection rate in shunt surgery compared to standard shunt catheter (non-AISC) from 8.13% to 4.09% (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.40-0.58; p=0.01; I2=46%). Subgroup analysis of different age groups showed that AISC had significant antimicrobial effects in all three groups (adult, infant, and adolescent). Follow-up time analysis showed that AISC was effective in preventing early shunt infections (within 6 months after implant). AISC is more effective in high-risk population (OR, 0.24; 95% CI, 0.14-0.40; p=0.60; I2=0%) than in general patient population.

Conclusion: The results of meta-analysis indicated that AISC is an effective method for reducing shunt infection. We recommend that AISC should be considered for use in infants and high-risk groups. For adult patients, the choice for AISC could be determined based on the treatment cost.
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http://dx.doi.org/10.3340/jkns.2019.0219DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7969052PMC
March 2021

Giant exchange bias induced tuning interfacial spins in polycrystalline FeO/CoO bilayers.

Phys Chem Chem Phys 2021 Mar;23(8):4805-4810

MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an 710049, China.

A giant exchange bias (EB) of 9600 Oe was observed in polycrystalline Fe3O4/CoO layers at 10 K after 20 kOe field cooling, and was attributed to the strong exchange coupling formed by the interfacial spins between the polycrystalline Fe3O4 and the CoO layer. It was found that at 10 K, the magnetic-moment difference (ΔM) between the zero field cooling curves and field cooling curves first increases and then decreases with the change of the field, and it reaches the maximum value at a field of 20 kOe, which suggests that the interfacial spins can be tuned by the cooling field. Furthermore, other magnetic properties, including field dependence, temperature dependence, and training effects, were investigated, which further confirmed that the interfacial spins play an important role in the EB effect. This work provides a method to tune the magnitude of the EB effect and reveals the mechanism of the dependency of EB on interfacial spins, which could guide the design of giant-EB-effect materials.
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http://dx.doi.org/10.1039/d0cp05902aDOI Listing
March 2021

Robust anti-infective multilayer coatings with rapid self-healing property.

Mater Sci Eng C Mater Biol Appl 2021 Feb 2;121:111828. Epub 2021 Jan 2.

School of Chemistry and Physics, Queensland University of Technology, Brisbane, Queensland 4000, Australia; Centre for Materials Science, Queensland University of Technology, Brisbane, Queensland 4000, Australia. Electronic address:

Surface coatings are extensively applied on biomedical devices to provide protection against biofouling and infections. However, most surface coatings prevent both bacteria and cells interactions with the biomaterials, limiting their uses as implants. Furthermore, damage to the surface such as scratches and abrasions can happen during transport and clinical usage, resulting in the loss of antibacterial property. In this work, we introduce an efficient method to fabricate stable anti-infective and self-healable multilayer coatings on stainless steel surface via a three-step procedue. Firstly, modified polyethyleneimine (PEI) and poly(acrylic acid) (PAA), both contain pendant furan groups, were deposited on the surface using Layer-by-Layer (LbL) self-assembly technique. Secondly, the polymer layers were cross-linked, via Diels-Alder cycloaddition, using a bismaleimide poly(ethylene glycol) linker, to enhance the stability of the coatings. Thirdly, the Diels-Alder adduct was utilised in the thiol-ene click reaction for post-modification of the coatings, which allowed for the grafting of antimicrobial poly(hexamethylene biguanide) (PHMB) and ε-poly(lysine) (EPL). The resultant multilayer coatings not only exhibited rapid self-healing property, with complete scratch closure within 30 min, but also demonstrated effective antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In addition, biofouling of bovine serum albumin was found to be inhibited on the coated surfaces. Furthermore, these coatings showed no toxicity effect towards seeded osteoblastic cells (MC3T3-E1) and evidence of anti-inflamatory activity when tested against macrophage cell line U-937. Our coating method thus represents an effective strategy for the anti-infective protection of biomedical-devices having direct contact with tissues.
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http://dx.doi.org/10.1016/j.msec.2020.111828DOI Listing
February 2021