Publications by authors named "Juan Gao"

250 Publications

Derivation and Validation of a Nomogram for Predicting 90-Day Survival in Patients With HBV-Related Acute-on-Chronic Liver Failure.

Front Med (Lausanne) 2021 16;8:692669. Epub 2021 Jun 16.

Department of Infectious Diseases, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.

Conventional prognostic models do not fully reflect the severity of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). This study aimed to establish an effective and convenient nomogram for patients with HBV-related ACLF. A nomogram was developed based on a retrospective cohort of 1,353 patients treated at the Third Affiliated Hospital of Sun Yat-sen University from January 2010 to June 2016. The predictive accuracy and discriminatory ability of the nomogram were determined by a concordance index (C-index) and calibration curve, and were compared with current scoring systems. The results were validated using an independent retrospective cohort of 669 patients consecutively treated at the same institution from July 2016 to March 2018. This study is registered at ClinicalTrials.gov (NCT03992898). Multivariable analysis of the derivation cohort found that independent predictors of 90-day survival were age, white blood cell (WBC) count, hemoglobin (Hb), aspartate aminotransferase (AST), total bilirubin (TBil), international normalized ratio, serum creatinine (Cr), alpha fetoprotein (AFP), serum sodium (Na), hepatic encephalopathy (HE), pre-existing chronic liver disease(PreLD), and HBV DNA load. All factors were included in the nomogram. The nomogram calibration curve for the probability of 90-day survival indicated that nomogram-based predictions were in good agreement with actual observations. The C-index of the nomogram was 0.790, which was statistically significantly greater than those for the current scoring systems in the derivation cohort ( < 0.001). The results were confirmed in the validation cohort. The proposed nomogram is more accurate in predicting the 90-day survival of patients with HBV-related ACLF than current commonly used methods.
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http://dx.doi.org/10.3389/fmed.2021.692669DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8241917PMC
June 2021

Biodistributions of l,d-Transpeptidases in Gut Microbiota Revealed by Labeling with Peptidoglycan Analogs.

ACS Chem Biol 2021 Jul 29;16(7):1164-1171. Epub 2021 Jun 29.

Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China.

By catalyzing a 3-3 cross-link in peptidoglycan, l,d-transpeptidases (Ldts) can cause resistance to β-lactams in some pathogens . However, the prevalence of Ldt and Ldt-mediated responses to different β-lactams have never been explored. Here, we apply an metabolic labeling strategy to study their biodistributions and Ldt-induced bacterial responses to β-lactams in the mouse gut microbiota. A tetrapeptide-based fluorescent probe that functions as a substrate for Ldts in Gram-positive bacteria efficiently labels ∼18% of total gut bacteria after gavage, suggesting Ldts' high prevalence in gut microbiota. The cellular distributions of 3-3 cross-links on three gut bacterial species were then identified with the aid of fluorescence hybridization to identify the bacterial taxa. After oral administration of two β-lactams, ampicillin and meropenem, only the latter efficiently inhibits the tetrapeptide labeling, suggesting that Ldts may be able to cause resistance to some β-lactams in the mammalian gut.
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http://dx.doi.org/10.1021/acschembio.1c00346DOI Listing
July 2021

ACE2 Expression Is Upregulated in Inflammatory Corneal Epithelial Cells and Attenuated by Resveratrol.

Invest Ophthalmol Vis Sci 2021 06;62(7):25

Tianjin Eye Hospital, Tianjin Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin, China.

Purpose: The ocular surface is considered an important route for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission. The expression level of the SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) is vital for viral infection. However, the regulation of ACE2 expression on the ocular surface is still unknown. We aimed to determine the change in ACE2 expression in inflamed corneal epithelium and explore potential drugs to reduce the expression of ACE2 on the ocular surface.

Methods: The expression of the SARS-CoV-2 receptors ACE2 and TMPRSS2 in human corneal epithelial cells (HCECs) was examined by qPCR and Western blotting. The altered expression of ACE2 in inflammatory corneal epithelium was evaluated in TNFα- and IL-1β-stimulated HCECs and inflamed mouse corneal epithelium, and the effect of resveratrol on ACE2 expression in HCECs was detected by immunofluorescence and Western blot analysis.

Results: ACE2 and TMPRSS2 are expressed on the human corneal epithelial cells. ACE2 expression is upregulated in HCECs by stimulation with TNFα and IL-1β and inflamed mouse corneas, including dry eye and alkali-burned corneas. In addition, resveratrol attenuates the increased expression of ACE2 induced by TNFα in HCECs.

Conclusions: This study demonstrates that ACE2 is highly expressed in HCECs and can be upregulated by stimulation with inflammatory cytokines and inflamed mouse corneal epithelium. Resveratrol may be able to reduce the increased expression of ACE2 on the inflammatory ocular surface. Our work suggests that patients with an inflammatory ocular surface may display higher ACE2 expression, which increases the risk of SARS-CoV-2 infection.
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http://dx.doi.org/10.1167/iovs.62.7.25DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8237080PMC
June 2021

CircDIP2C ameliorates oxidized low-density lipoprotein-induced cell dysfunction by binding to miR-556-5p to induce TET2 in human umbilical vein endothelial cells.

Vascul Pharmacol 2021 Aug 18;139:106887. Epub 2021 Jun 18.

Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, China.

Circular RNAs (circRNAs) are a group of conserved noncoding RNAs. Recent reports reveal that circRNAs play vital parts in cardiovascular system, including atherosclerosis (AS). The present study is designed to reveal the role of circRNA DIP2C-disco interacting protein 2 homolog C (circDIP2C) in oxidized low-density lipoprotein (ox-LDL)-triggered damage of human umbilical vein endothelial cells (HUVECs). The expression levels of circDIP2C, microRNA-556-5p (miR-556-5p) and tet methylcytosine dioxygenase 2 (TET2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was determined by western blot analysis. Cell viability and angiogenesis were demonstrated by cell counting kit-8 and tube formation assays, respectively. The levels of reactive oxygen species (ROS) and malondialdehyde (MDA) were checked by ROS and MDA determination assays. Superoxide dismutase (SOD) and lactate dehydrogenase (LDH) activity assays were performed to detect the activity of SOD and LDH. The binding sites of miR-556-5p in circDIP2C or TET2 were predicted by online databases, and identified by dual-luciferase reporter, RNA immunoprecipitation and RNA pull-down assays. CircDIP2C and TET2 expression were obviously decreased, while miR-556-5p expression was increased in ox-LDL-induced HUVECs in comparison with untreated HUVECs. Ox-LDL treatment inhibited cell viability and angiogenesis, promoted oxidative stress, enhanced cytotoxicity and activated NLR family pyrin domain containing 3 (NLRP3) inflammasome pathway. CircDIP2C upregulation protected HUVECs from ox-LDL-induced injury. Additionally, circDIP2C directly bound to miR-556-5p, which was further found to target TET2. MiR-556-5p mimics or TET2 silencing could attenuate the effect of circDIP2C overexpression on ox-LDL-induced cell disorder. Thus, we came a conclusion that circDIP2C protected against ox-LDL-induced HUVEC damage by upregulating TET2 expression through sponging miR-556-5p, which provided a strategy for the therapy of AS.
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http://dx.doi.org/10.1016/j.vph.2021.106887DOI Listing
August 2021

-Deficient Neutrophils Promote Hematopoietic Stem/Progenitor Cell Proliferation Mesenchymal Stem Cells.

Front Cell Dev Biol 2021 27;9:650599. Epub 2021 May 27.

State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China.

Myeloid cells have been identified as hematopoietic stem cell (HSC)-regulating cells. However, the mechanisms by which myeloid cells regulate the function of HSCs are not fully defined. Our previous study indicated that the HSCs are over-expanded in mice. Here, using and models, we found that -deficient neutrophils remodeled the bone marrow environment and induced expansion of HSCs . Further studies showed that loss of Rheb1 impaired neutrophils' ability to secrete IL-6, led mesenchymal stem cells (MSCs) to produce more SCF, and promote HSC proliferation. We further found that IL-6 suppressed SCF mRNA expression in human MSCs. Interesting, the high level of IL-6 was also related with poor survival of chronic myeloid leukemia (CML) patients, and higher expression of IL-6 in CML cells is associated with the lower expression of SCF in MSCs in patients. Our studies suggested that blocking IL-6 signaling pathway might stimulate MSCs to secrete more SCF, and to support hematopoietic stem/progenitor cells proliferation.
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http://dx.doi.org/10.3389/fcell.2021.650599DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8191467PMC
May 2021

Exercise attenuates angiotensinⅡ-induced muscle atrophy by targeting PPARγ/miR-29b.

J Sport Health Sci 2021 Jun 8. Epub 2021 Jun 8.

Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, School of Life Science, Shanghai University, Shanghai 200444, China; Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, Shanghai 200444, China. Electronic address:

Background: Exercise is beneficial for muscle atrophy. Peroxisome proliferator-activated receptor gamma (PPARγ) and microRNA-29b (miR-29b) have been reported to be responsible for angiotensin Ⅱ (AngⅡ)-induced muscle atrophy. However, it is unclear whether exercise can protect AngⅡ-induced muscle atrophy by targeting PPARγ/miR-29b.

Methods: Skeletal muscle atrophy in both the control group and the run group was established by AngⅡ infusion; after 1 week of exercise training, the mice were sacrificed, and muscle weight was determined. Myofiber size was measured by hematoxylin-eosin and wheat-germ agglutinin staining. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling staining. The expression level of muscle atrogenes, including F-box only protein 32 (FBXO32, also called Atrogin-1) and muscle-specific RING-finger 1 (MuRF-1), the phosphorylation level of protein kinase B (PKB, also called AKT)/forkhead box O3A (FOXO3A)/mammalian target of rapamycin (mtorTOR) pathway proteins, the expression level of PPARγ and apoptosis-related proteins, including B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X (Bax), cysteine-aspartic acid protease 3 (caspase-3), and cleaved-caspase-3, were determined by western blot. The expression level of miR-29b was checked by reverse-transcription quantitative polymerase chain reaction. A PPARγ inhibitor (T0070907) or miR-29b overexpression adeno-associated virus serotype-8 (AAV8) was used to demonstrate whether PPARγ activation or miR-29b inhibition mediates the beneficial effects of exercise in AngⅡ-induced muscle atrophy.

Results: Exercise can significantly attenuate AngⅡ-induced muscle atrophy, which is demonstrated by increased skeletal muscle weight, cross-sectional area of myofiber, and activation of AKT/mTOR signaling and by decreased atrogenes expressions and apoptosis. In AngⅡ-induced muscle atrophy mice models, PPARγ was elevated whereas miR-29b was decreased by exercise. The protective effects of exercise in AngⅡ-induced muscle atrophy were inhibited by a PPARγ inhibitor (T0070907) or miR-29b overexpression AAV8.

Conclusion: Exercise attenuates AngⅡ-induced muscle atrophy by activation of PPARγ and suppression of miR-29b.
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http://dx.doi.org/10.1016/j.jshs.2021.06.002DOI Listing
June 2021

Nitrogen-Doped Graphdiyne as a Robust Electrochemical Biosensing Platform for Ultrasensitive Detection of Environmental Pollutants.

Anal Chem 2021 06 10;93(24):8656-8662. Epub 2021 Jun 10.

CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China.

Owing to its unique chemical structure, natural pores, high structure defects, good surface hydrophilicity and biocompatibility, and favorable electrical conductivity, nitrogen-doped graphdiyne (NGDY) has been attracting attention in the application of electrochemical sensing. Taking advantage of these fascinating electrochemical properties, for the first time, two types of electrochemical enzymatic biosensors were fabricated for the respective detection of organophosphorus pesticides (OPs) and phenols based on the immobilization of acetylcholinesterase or tyrosinase with NGDY. Results revealed that the sensitivities of the NGDY-based enzymatic biosensors were almost twice higher than that of the matching biosensor in the absence of NGDY, proving that NGDY plays a vital role in immobilizing the enzymes and improving the performance of the fabricated biosensors. The effects of nitrogen doping on improving the biosensing performance were studied in depth. Graphitic N atoms can enhance the electrical conductivity, while imine N and pyridinic N can help to adsorb and accumulate the substance molecules to the electrode surface, all of which contribute to the significantly improved performance. Furthermore, these two types of biosensors also demonstrated excellent reproducibility, high stability, and good recovery rate in real environmental samples, which showed a valuable way for the rapid detection of OPs and phenols in the environment. With these excellent performances, it is strongly anticipated that NGDY has tremendous potential to be applied to many other biomedical and environmental fields.
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http://dx.doi.org/10.1021/acs.analchem.1c01800DOI Listing
June 2021

Analysis of umami taste substances of morel mushroom (Morchella sextelata) hydrolysates derived from different enzymatic systems.

Food Chem 2021 Nov 25;362:130192. Epub 2021 May 25.

College of Food Science and Technology, Nanjing Agricultural University/Key Laboratory of Edible Mushroom Processing, Ministry of Agriculture and Rural Affairs, Nanjing, Jiangsu 210095, PR China. Electronic address:

Seven enzyme groups were applied to hydrolyze broken fruiting bodies of morel mushroom (Morchella sextelata) to extract umami substances. Physical-chemical properties, as well as compositions and concentrations of quintessential umami compounds of morel hydrolysates were analyzed. Electronic tongue and electronic nose were used to evaluate the sensory characteristics. The results suggested that peptides below 3 kDa showed the highest correlation with umami taste. Morel hydrolysate obtained from Neutrase-Flavourzyme (NF) combination contained the most contents of small peptides (<3 kDa), free amino acids (224.83 ± 0.87 mg/g), as well as flavor 5'-nucleotides (4.84 ± 0.32 mg/g), giving the best overall flavor properties. The reaction conditions of NF were optimized by response surface methodology (RSM). The highest degree of hydrolysis (DH) was up to 36.64%. An enzymatic hydrolysis approach was established to develop novel flavor products with high umami and low bitter taste from morel mushroom.
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http://dx.doi.org/10.1016/j.foodchem.2021.130192DOI Listing
November 2021

Overlooked contribution of water column to nitrogen removal in estuarine turbidity maximum zone (TMZ).

Sci Total Environ 2021 Sep 14;788:147736. Epub 2021 May 14.

School of Geographic Sciences, East China Normal University, Shanghai 200241, China; Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai 200241, China.

Estuarine systems are important sites of eliminating reactive nitrogen (N) delivered from land to sea. Numerous studies have focused on N cycling in estuarine sediment. However, the N elimination role of suspended sediments in estuarine turbid water column, which might provide anaerobic microenvironment for N loss, is rarely considered. This study examined the community dynamics and activities of denitrifying and anaerobic ammonium oxidation (anammox) bacteria in the water column of the turbidity maximum zone (TMZ) of the Yangtze Estuary, using molecular and N isotope-tracing techniques. Results showed that the anammox bacterial community was dominated by Candidatus Kuenenia and Candidatus Brocadia in the TMZ water column, while the main nirS-harboring denitrifiers were affiliated with Rhodobacterales. The denitrifying nirS gene was two orders of magnitude more abundant than anammox bacterial 16S rRNA gene, ranging from 1.77 × 10 to 1.42 × 10 copies l and from 7.68 × 10 to 4.27 × 10 copies l, respectively. Compared with anammox, denitrification, with rates of 0.88 to 20.83 μmol N l d, overwhelmingly dominated the N removal in the TMZ water column and was significantly correlated to suspended sediment concentrations (SSC). Based on the measured N removal rates, it was estimated that about 2.5 × 10 ton N was annually removed from the TMZ water column, accounting for approximately 18.5% of the total inorganic N (TIN) discharged from the Yangtze River. Overall, this study implies the importance of estuarine turbid water column in controlling N budget, and also improves the understanding of N loss mechanisms in estuarine TMZ systems.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147736DOI Listing
September 2021

Effect of Huang-Lian Jie-Du Decoction on Glucose and Lipid Metabolism in Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis.

Front Pharmacol 2021 29;12:648861. Epub 2021 Apr 29.

Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.

Type 2 diabetes mellitus (T2DM) is a heterogeneous disease characterized by persistent hyperglycemia. Huang-Lian Jie-Du decoction (HLJDD) is a traditional Chinese medicine formula which is widely used in treating T2DM in China. A thorough understanding of current body of evidence is needed. this study aims to summarize the clinical evidence of HLJDD for T2DM to provide an up-to-date and accurate understanding of this issue for research and clinical practice. Six databases were searched from inception to June 27, 2020 without language and publication status restrictions and randomized controlled trials about HLJDD on T2DM were included. Two evaluators searched and screened citations independently. Risk of bias was assessed by 2019 version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB2). Risk ratio (RR) with 95% confidence interval (CI) was used as an effect measure for dichotomous outcomes and mean difference (MD) with 95% CI was used for continuous outcomes. Subgroup analyses and sensitivity analyses were carried out. Nine studies including 811 participants were included in this study. The overall risk of bias was high risk. Compared with metformin alone, combination treatment of HLJDD and metformin may result in a reduction in HbA1c, FBG, 2hPG, HOMA-IR and an improved lipid metabolism. Evidence comparing HLJDD and metformin or no intervention or placebo was insufficient. The quality of evidence was low. Current evidence about HLJDD on T2DM is still uncertain and more high-quality studies are needed to firmly establish the clinical efficacy and safety of HLJJD.
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http://dx.doi.org/10.3389/fphar.2021.648861DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8117159PMC
April 2021

DUXAP8 knockdown inhibits the development of melanoma by regulating the miR-3182/NUPR1 pathway.

Oncol Lett 2021 Jul 27;22(1):495. Epub 2021 Apr 27.

Department of Dermatology, The Affiliated Changzhou No. 2 People's Hospital with Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China.

Double homeobox A pseudogene 8 (DUXAP8) has been reported to regulate the growth of several types of cancers, such as breast cancer and ovarian cancer. However, its role in melanoma remains unclear. In the present study, the mechanism through which DUXAP8 regulates melanoma progression was explored. The expression levels of DUXAP8 were determined in 43 samples from patients with melanoma in different stages, as well as human epidermal melanocytes cells and malignant melanoma cell lines using reverse transcription-quantitative PCR (RT-qPCR). The prognosis of patients was analyzed using the Kaplan-Meier method. The relationship between lncRNA DUXAP8 expression and microRNA (miR)-3182 or nuclear protein 1 transcriptional regulator (NUPR1) levels was analyzed using Pearson's correlation. Luciferase reporter and RNA pull-down were used to examine the interactions between these molecules. Proliferation was assessed using Cell Counting-Kit-8. Transwell assays were used to examine cell migration and invasion. lncRNA DUXAP8 was upregulated in melanoma tissue and cells compared with normal tissues and cells. The levels of DUXAP8 inversely correlated with survival time of patients with melanoma. Knockdown of lncRNA DUXAP8 inhibited proliferation, migration and invasion of melanoma cells. lncRNA DUXAP8 targeted miR-3182, while miR-3182 targeted NUPR1. The overexpression of NUPR1 reversed the effects of DUXAP8 knockdown or miR-3182 mimic on melanoma progression. In conclusion, lncRNA DUXAP8 downregulation inhibits the development of melanoma by regulating the miR-3182/NUPR1 axis.
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http://dx.doi.org/10.3892/ol.2021.12756DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8108271PMC
July 2021

Potential Networks Regulated by MSCs in Acute-On-Chronic Liver Failure: Exosomal miRNAs and Intracellular Target Genes.

Front Genet 2021 23;12:650536. Epub 2021 Apr 23.

Department of Infectious Diseases, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.

Acute-on-chronic liver failure (ACLF) is a severe syndrome associated with high mortality. Alterations in the liver microenvironment are one of the vital causes of immune damage and liver dysfunction. Human bone marrow mesenchymal stem cells (hBMSCs) have been reported to alleviate liver injury via exosome-mediated signaling; of note, miRNAs are one of the most important cargoes in exosomes. Importantly, the miRNAs within exosomes in the hepatic microenvironment may mediate the mesenchymal stem cell (MSC)-derived regulation of liver function. This study investigated the hepatocyte exosomal miRNAs which are regulated by MSCs and the target genes which have potential in the treatment of liver failure. Briefly, ACLF was induced in mice using carbon tetrachloride and primary hepatocytes were isolated and co-cultured (or not) with MSCs under serum-free conditions. Exosomes were then collected, and the expression of exosomal miRNAs was assessed using next-generation sequencing; a comparison was performed between liver cells from healthy ACLF animals. Additionally, to identify the intracellular targets of exosomal miRNAs in humans, we focused on previously published data, i.e., microarray data and mass spectrometry data in liver samples from ACLF patients. The biological functions and signaling pathways associated with differentially expressed genes were predicted using gene ontology and Kyoto Encyclopedia of Genes and Genomics enrichment analyses; hub genes were also screened based on pathway analysis and the prediction of protein-protein interaction networks. Finally, we constructed the hub gene-miRNA network and performed correlation analysis and qPCR validation. Importantly, our data revealed that MSCs could regulate the miRNA content within exosomes in the hepatic microenvironment. MiR-20a-5p was down-regulated in ACLF hepatocytes and their exosomes, while the levels of chemokine C-X-C Motif Chemokine Ligand 8 (CXCL8; interleukin 8) were increased in hepatocytes. Importantly, co-culture with hBMSCs resulted in up-regulated expression of miR-20a-5p in exosomes and hepatocytes, and down-regulated expression of CXCL8 in hepatocytes. Altogether, our data suggest that the exosomal miR-20a-5p/intracellular CXCL8 axis may play an important role in the reduction of liver inflammation in ACLF in the context of MSC-based therapies and highlights CXCL8 as a potential target for alleviating liver injury.
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http://dx.doi.org/10.3389/fgene.2021.650536DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8102832PMC
April 2021

Neck circumference and waist circumference associated with cardiovascular events in type 2 diabetes (Beijing Community Diabetes Study 23).

Sci Rep 2021 May 4;11(1):9491. Epub 2021 May 4.

Diabetes Trials Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.

Obesity increases the risk of developing cardiovascular disease and other metabolic diseases. We intended to compare three different anthropometric indicators of obesity, in predicting the incidence of cardiovascular events in Chinese type 2 diabetes. Beijing Community Diabetes Study was a prospective multi-center study conducted in Beijing community health centers. Type 2 diabetes patients from fourteen community health centers were enrolled at baseline. The primary endpoint was cardiovascular events. The upper quartile of neck circumference (NC) was set as greater NC. A total of 3299 diabetes patients were enrolled. In which, 941 (28.52%) had cardiovascular disease at baseline. Logistic analysis showed that central obesity (waist circumference (WC) above 90 cm in men and 85 cm in women) and greater NC were all related to baseline cardiovascular disease (adjusted OR = 1.49, and 1.55). After 10-year follow-up, 340 (10.31%) had cardiovascular events. Compared with patients without cardiovascular events, those having cardiovascular events had higher BMI, larger WC and NC. Cox regression analysis showed that greater WC and NC were all associated with the occurrence of cardiovascular events (adjusted HR = 1.41, and 1.38). A higher NC and WC might increase the risk of cardiovascular events by about 40% in type 2 diabetes patients in Beijing communities.
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http://dx.doi.org/10.1038/s41598-021-88927-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8097072PMC
May 2021

Two transformation pathways of Acetaminophen with Fe saturated clay particles in dark or light.

Chemosphere 2021 Sep 1;278:130399. Epub 2021 Apr 1.

Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China. Electronic address:

Acetaminophen (AP) has been frequently detected in different environments due to its wide usage as a common analgesic and antipyretic pharmaceutical. Excess residual of AP in the environment may cause biological risk. However, information about its environmental behaviors was limited, especially the interactions with clay minerals. In this study, AP transformation mediated by Fe saturated clay particles was systematically investigated. The results showed 47.6 ± 1.1% or 78.9 ± 0.5% of AP was removed in the presence of Fe-montmorillonite respectively in dark or under simulated sunlight irradiation after 10 h. The hypothesized mechanism was that exchangeable ferric ions can either obtain electron from AP to form AP radical, or produce OH under light, which can further react with AP. In dark condition, AP radicals could cross-couple with each other to form dimers, while oxidation products were also detected under light irradiation due to OH attacking. Moreover, higher concentration of dissolved oxygen (DO) facilitated Fe regeneration on clay surfaces and more reactive Fe species distributed in lower pH, which could significantly enhance the removal of AP both in dark and light. Results of this study revealed that clay minerals played important roles in the abiotic transformation of AP either in dark or under light irradiation, and oligomerization other than mineralization were the dominant processes.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130399DOI Listing
September 2021

Reactive oxygen species formation in thiols solution mediated by pyrogenic carbon under aerobic conditions.

J Hazard Mater 2021 08 22;415:125726. Epub 2021 Mar 22.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China. Electronic address:

Previous studies have demonstrated that pyrogenic carbon can mediate the reductive degradation of pollutants in solutions containing reducing reagents under anaerobic conditions. However, few studies have investigated oxidative species formation and pollutants transformation directly mediated by pyrogenic carbon under aerobic conditions. In this study, we found that activated carbon (AC) can not only mediate reductive hexachloroethane degradation in the absence of O but also mediate the oxidation of As(III) and sulfanilamide in L-Cysteine (Cys, a naturally abundant thiol compound) solution under aerobic conditions. Electron paramagnetic resonance and quenching studies indicated that O, HO and OH was formed in Cys/AC system under aerobic conditions. High O content favored the formation of OH, indicating that O participated in OH production. In addition, an increase in AC concentration and specific surface area led to increased formation of OH, and other pyrogenic carbon materials such as biochar and graphite were also found capable of mediating the formation of OH. This study demonstrates that pyrogenic carbon could mediate OH formation in solutions containing reductive reagents under aerobic conditions, which provides a new perspective for studying the behavior of pyrogenic carbon in the environment and its role in biogeochemical processes.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125726DOI Listing
August 2021

In-situ synthesis of ultrasmall Au nanoparticles on bimetallic metal-organic framework with enhanced electrochemical activity for estrone sensing.

Anal Chim Acta 2021 Apr 24;1152:338242. Epub 2021 Jan 24.

Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China. Electronic address:

In this work, ultrasmall Au nanoparticles decorated bimetallic metal-organic framework (US Au [email protected]) hybrids were facilely prepared by a sequential ion exchange and in-situ chemical reduction strategy. Numerous of Au nanoparticles with size less than 5 nm was homogeneously dispersed on the surface of the whole bimetallic AuZn-MOF polyhedrons. The integration of ultrasmall Au nanoparticles greatly enhanced the electron transfer capacity and electrochemical active surface area of the metal-organic framework host. Compared with the pristine Zn-MOF, bimetallic AuZn-MOF, the as-synthesized US Au [email protected] hybrids exhibited remarkably promoted electrochemical activity toward the oxidation and sensing of endocrine-disrupting chemical (EDC) estrone. As a result, a highly sensitive electrochemical sensing platform was developed for the detection of estrone in the range of 0.05 μM-5 μM with limit of detection of 12.3 nM (S/N = 3) and sensitivity of 101.3 μA μM cm. Considering the structural diversity of MOFs and superior property of ultrasmall Au nanoparticles, the strategy proposed here may open a new avenue for the design and synthesis of other high-activity nanomaterials for electrochemical sensing or other challenging fields.
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http://dx.doi.org/10.1016/j.aca.2021.338242DOI Listing
April 2021

Persistent Free Radicals from Low-Molecular-Weight Organic Compounds Enhance Cross-Coupling Reactions and Toxicity of Anthracene on Amorphous Silica Surfaces under Light.

Environ Sci Technol 2021 03 26;55(6):3716-3726. Epub 2021 Feb 26.

Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008, China.

Polycyclic aromatic hydrocarbon (PAH) contamination has raised great environmental concerns, while the effects of low-molecular-weight organic compounds (LMWOCs) on PAH photodegradation at amorphous silica (AS)/air interfaces have been largely ignored. In this study, the phototransformation of anthracene (ANT) at amorphous silica (AS)/air interfaces was investigated with the addition of LMWOCs. ANT removal was attributed to OH attacking and the energy transfer process via ANT*. Light irradiation induced the fractured ≡SiO or ≡Si generation on AS surfaces, which could react with absorbed HO and O to generate OH and further yield a series of hydroxylated products of ANT. The presence of citric acid and oxalic acid improved OH generation and enhanced ANT removal by 1.0- and 2.2-fold, respectively. For comparison, the presence of catechol and hydroquinone significantly decreased ANT removal and produced coupling products. The results of density functional theory calculations suggest that persistent free radicals (PFRs) on AS surfaces from catechol or hydroquinone after OH attacking prefer to cross-couple with ANT via C-C bonding rather than self-couple. Dianthrone and cross-coupling products might possess higher ecotoxicity, while hydroxylated products were less ecotoxic than their parent compounds based on Ecological Structure Activity Relationships (ECOSAR) estimation. The results of this study revealed the potential ecotoxicity of PAH-adsorbed particulates coexisting with LMWOCs and also provided a new insight into PAH transformation through PFR pathways.
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http://dx.doi.org/10.1021/acs.est.0c07472DOI Listing
March 2021

Enhanced and selective phototransformation of chlorophene on aluminum hydroxide-humic complexes.

Water Res 2021 Apr 4;193:116904. Epub 2021 Feb 4.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China. Electronic address:

Mineral-humic complexes, known as mineral-associated organic matter (MAOM), are ubiquitous in natural waters. However, the interaction between organic pollutants and MAOM remains elusive, which may affect their degradation process. In this study, photochemical transformation of chlorophene (CP) in the presence of MAOM, prepared by coating aluminum hydroxide with humic acid (HA-HAO), was investigated. Our results showed that the degradation of CP was significantly enhanced in the presence of HA-HAO, and the degradation rate constant was ~5 times as that with HA only. It was because the adsorption of CP to HA-HAO particles was greatly enhanced, and concentration of reactive oxygen species (ROS) was increased on HA-HAO surfaces, which further promoted the reactions between CP and ROS. The quenching experiments combined with EPR technology confirmed that superoxide anion (O) was the primary reactive radical on CP photodegradation. More importantly, the degradation of CP with HA-HAO followed a hydroxylation process, rather than the oligomerization reaction with HA only. Spectroscopic analysis provided direct evidence for the formation of hydrogen bonding between CP phenolic hydroxyl group and surface oxygen of HAO, which would suppress the reactivity of phenolic hydroxyl group, consequently the ortho- and meta-positions of CP became more facile for the hydroxylation reaction. This study shows the importance of MAOM in altering the photochemical behavior and transformation pathway of organic contaminants.
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http://dx.doi.org/10.1016/j.watres.2021.116904DOI Listing
April 2021

Curcumin suppresses colorectal tumorigenesis via the Wnt/β-catenin signaling pathway by downregulating Axin2.

Oncol Lett 2021 Mar 6;21(3):186. Epub 2021 Jan 6.

Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education/College of Life Science, Northwest University, Xi'an, Shaanxi 710069, P.R. China.

Colorectal cancer (CRC) is the third most common cancer worldwide, with high incidence and mortality rates. Conventional therapies, including surgery, chemotherapy and radiation, are extensively used for the treatment of CRC. However, patients present with adverse effects, such as toxicity, hepatic injury and drug resistance. Thus, there is an urgent requirement to identify effective and safe therapy for CRC. Curcumin (CUR), a polyphenol substrate extracted from the of , has been extensively studied for the treatment of CRC due to its high efficacy and fewer side effects. Previous studies have reported that several signaling pathways, such as NF-κB, Wnt/β-catenin, are involved in the antitumor effects of CUR . However, the effect and mechanisms are not yet fully understood. The present study aimed to determine the molecular mechanism of colorectal cancer . Reverse transcription-quantitative PCR, western blot and immunohistochemistry analyses were performed to determine the underlying molecular mechanism of curcumin's anti-cancer effect in azoxymethane-dextran sodium sulfate induced colorectal cancer. The results of the present study demonstrated that CUR suppressed tumorigenesis in AOM-DSS induced CRC in mice, and anticancer effects were exerted by suppressing the expression of pro-inflammatory cytokines, and downregulating Axin2 in the Wnt/β-catenin signaling pathway. Taken together, these results exhibit the potential mechanisms of the anticancer effects of CUR, and highlight Axin2 as a potential therapeutic target for CRC.
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http://dx.doi.org/10.3892/ol.2021.12447DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7816292PMC
March 2021

Novel roles of an intragenic G-quadruplex in controlling microRNA expression and cardiac function.

Nucleic Acids Res 2021 03;49(5):2522-2536

Department of Cardiology, Institute of Vascular Medicine, NHC Key Laboratory of Cardiovascular Molecular Biology and RegulatoryPeptides, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Third Hospital, Beijing 100191, China.

Simultaneous dysregulation of multiple microRNAs (miRs) affects various pathological pathways related to cardiac failure. In addition to being potential cardiac disease-specific markers, miR-23b/27b/24-1 were reported to be responsible for conferring cardiac pathophysiological processes. In this study, we identified a conserved guanine-rich RNA motif within the miR-23b/27b/24-1 cluster that can form an RNA G-quadruplex (rG4) in vitro and in cells. Disruption of this intragenic rG4 significantly increased the production of all three miRs. Conversely, a G4-binding ligand tetrandrine (TET) stabilized the rG4 and suppressed miRs production in human and rodent cardiomyocytes. Our further study showed that the rG4 prevented Drosha-DGCR8 binding and processing of the pri-miR, suppressing the biogenesis of all three miRs. Moreover, CRISPR/Cas9-mediated G4 deletion in the rat genome aberrantly elevated all three miRs in the heart in vivo, leading to cardiac contractile dysfunction. Importantly, loss of the G4 resulted in reduced targets for the aforementioned miRs critical for normal heart function and defects in the L-type Ca2+ channel-ryanodine receptor (LCC-RyR) coupling in cardiomyocytes. Our results reveal a novel mechanism for G4-dependent regulation of miR biogenesis, which is essential for maintaining normal heart function.
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http://dx.doi.org/10.1093/nar/gkab055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7969000PMC
March 2021

An improved patch-based regularization method for PET image reconstruction.

Quant Imaging Med Surg 2021 Feb;11(2):556-570

Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.

Background: Statistical reconstruction methods based on penalized maximum likelihood (PML) are being increasingly used in positron emission tomography (PET) imaging to reduce noise and improve image quality. Wang and Qi proposed a patch-based edge-preserving penalties algorithm that can be implemented in three simple steps: a maximum-likelihood expectation-maximization (MLEM) image update, an image smoothing step, and a pixel-by-pixel image fusion step. The pixel-by-pixel image fusion step, which fuses the MLEM updated image and the smoothed image, involves a trade-off between preserving the fine structural features of an image and suppressing noise. Particularly when reconstructing images from low-count data, this step cannot preserve fine structural features in detail. To better preserve these features and accelerate the algorithm convergence, we proposed to improve the patch-based regularization reconstruction method.

Methods: Our improved method involved adding a total variation (TV) regularization step following the MLEM image update in the patch-based algorithm. A feature refinement (FR) step was then used to extract the lost fine structural features from the residual image between the TV regularized image and the fused image based on patch regularization. These structural features would then be added back to the fused image. With the addition of these steps, each iteration of the image should gain more structural information. A brain phantom simulation experiment and a mouse study were conducted to evaluate our proposed improved method. Brain phantom simulation with added noise were used to determine the feasibility of the proposed algorithm and its acceleration of convergence. Data obtained from the mouse study were divided into event count sets to validate the performance of the proposed algorithm when reconstructing images from low-count data. Five criteria were used for quantitative evaluation: signal-to-noise ratio (SNR), covariance (COV), contrast recovery coefficient (CRC), regional relative bias, and relative variance.

Results: The bias and variance of the phantom brain image reconstructed using the patch-based method were 0.421 and 5.035, respectively, and this process took 83.637 seconds. The bias and variance of the image reconstructed by the proposed improved method, however, were 0.396 and 4.568, respectively, and this process took 41.851 seconds. This demonstrates that the proposed algorithm accelerated the reconstruction convergence. The CRC of the phantom brain image reconstructed using the patch-based method was iterated 20 times and reached 0.284, compared with the proposed method, which reached 0.446. When using a count of 5,000 K data obtained from the mouse study, both the patch-based method and the proposed method reconstructed images similar to the ground truth image. The intensity of the ground truth image was 88.3, and it was located in the 102 row and the 116 column. However, when the count was reduced to below 40 K, and the patch-based method was used, image quality was significantly reduced. This effect was not observed when the proposed method was used. When a count of 40 K was used, the image intensity was 58.79 when iterated 100 times by the patch-based method, and it was located in the 102 row and the 116 column, while the intensity when iterated 50 times by the proposed method was 63.83. This suggests that the proposed method improves image reconstruction from low-count data.

Conclusions: This improved method of PET image reconstruction could potentially improve the quality of PET images faster than other methods and also produce better reconstructions from low-count data.
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http://dx.doi.org/10.21037/qims-20-19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7779915PMC
February 2021

Human Serum-derived Extracellular Vesicles Protect A549 from PM -induced Cell Apoptosis.

Biomed Environ Sci 2021 Jan;34(1):40-49

Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, School of Life Science, Shanghai University, Shanghai 200444, China.

Objective: Epidemiological studies reveal that exposure to fine particulate matter (aerodynamic diameter ≤ 2.5 μm, PM ) increases the morbidity and mortality of respiratory diseases. Emerging evidence suggests that human circulating extracellular vesicles (EVs) may offer protective effects against injury caused by particulate matter. Currently, however, whether EVs attenuate PM -induced A549 cell apoptosis is unknown.

Methods: EVs were isolated from the serum of healthy subjects, quantified nanoparticle tracking analysis, and qualified by the marker protein CD63. PM -exposed (50 μg/mL) A549 cells were pre-treated with 10 μg/mL EVs for 24 h. Cell viability, cell apoptosis, and AKT activation were assessed via Cell Counting Kit-8, flow cytometry, and Western blot, respectively. A rescue experiment was also performed using MK2206, an AKT inhibitor.

Results: PM exposure caused a 100% increase in cell apoptosis. EVs treatment reduced cell apoptosis by 10%, promoted cell survival, and inhibited the PM -induced upregulation of Bax/Bcl2 and cleaved caspase 3/caspase 3 in PM -exposed A549 cells. Moreover, EVs treatment reversed PM -induced reductions in p-AKT and p-AKT . AKT inhibition attenuated the anti-apoptotic effect of EVs treatment on PM -exposed A549 cells.

Conclusions: EVs treatment promotes cell survival and attenuates PM -induced cell apoptosis AKT phosphorylation. Human serum-derived EVs may be an efficacious novel therapeutic strategy in PM -induced lung injury.
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http://dx.doi.org/10.3967/bes2021.006DOI Listing
January 2021

Efficient activation of peroxymonosulfate by copper sulfide for diethyl phthalate degradation: Performance, radical generation and mechanism.

Sci Total Environ 2020 Dec 17;749:142387. Epub 2020 Sep 17.

Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.

Copper-containing minerals have been extensively used in Fenton-like processes for degradation of pollutants and have exhibited great potential for environmental remediation. This work reports the first use of copper sulfide (CuS), a typical Cu-mineral, for the activation of peroxymonosulfate (PMS) for pollutant degradation; the study also elucidates the underlying mechanism of these processes. Copper sulfide effectively activated PMS to degrade diethyl phthalate (DEP). Electron paramagnetic resonance, free radical quenching, X-ray photoelectron spectroscopy, X-ray diffraction analyses and DFT calculations confirmed that ≡Cu (I)/≡Cu (II) cycling on the surface of CuS provided the main pathway to activate PMS to produce highly oxidative species. Unlike conventional sulfate radical-based PMS activation processes, hydroxyl radical (OH) were found to be the dominant radical in the tested CuS/PMS system, which performed more efficiently than an alternative OH-based oxidation system (CuS/HO) for DEP degradation. In addition, the presence of anions such Cl and NO has limited inhibition effects on DEP degradation. Overall, this study provides an efficient pathway for PMS-based environmental remediation as well as a new insight into the mechanism of PMS activation by Cu-containing minerals.
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http://dx.doi.org/10.1016/j.scitotenv.2020.142387DOI Listing
December 2020

Nano FeO embedded in montmorillonite with citric acid enhanced photocatalytic activity of nanoparticles towards diethyl phthalate.

J Environ Sci (China) 2021 Mar 2;101:248-259. Epub 2020 Sep 2.

Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science Chinese Academy of Sciences, Nanjing 210008, China. Electronic address:

Nano-FeO embedded in montmorillonite particles (Fe-Mt) were prepared to degrade diethyl phthalate (DEP) with citric acid (CA) under xenon light irradiation. Compared to pristine montmorillonite (Na-Mt), the embedding process increased 14.5-fold of iron content and 1.8-fold of specific surface area. The synthesized Fe-Mt have more oxygen vacancies than FeO nanoparticles (nFeO), which could induce more reactive oxygen species (ROSs) generation in the presence of CA under xenon lamp irradiation. Fe-Mt with CA enhanced photo-assisted degradation of DEP 2.5 times as compared to nFeO with CA. Quenching experiments, electron paramagnetic resonance (EPR) spectroscopy and identification of products confirmed that surface-bound •OH was the main radical to degrade DEP. Common anions (i.e., NO, CO, Cl) and humic acid could compete •OH with DEP and cause slower degradation of DEP. The removal efficiency of DEP was more than 56% with Fe-Mt after three recycles, and the dissolved Fe concentration from Fe-Mt was below 75 μmol/L, indicating Fe-Mt had a good stability as a catalyst. Fe-Mt together with CA appeared to be a promising strategy to remove organic pollutants in surface water, or topsoil under solar irradiation.
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http://dx.doi.org/10.1016/j.jes.2020.08.019DOI Listing
March 2021

Pericarpium protects against isoproterenol-induced chronic heart failure via activation of PPARγ.

Ann Transl Med 2020 Nov;8(21):1396

Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.

Background: Accumulated clinical trials and animal studies showed that Qiliqiangxin (QLQX), a traditional Chinese medicine formula containing extracts of 11 herbs, exerts beneficial effects on chronic heart failure (HF). Pericarpium (CRP), one herbal medicine in QLQX, has been widely used in treatment against digestive, respiratory and cardiovascular diseases (CVDs) in China. However, the cardiac protective effects and mechanisms of CRP are still unclear.

Methods: The effects of CRP were investigated in isoproterenol (ISO)-induced chronic HF mice model and neonatal rat ventricular cardiomyocytes (NRVMs) treated with ISO. Echocardiography was used to determine cardiac function. Hematoxylin-eosin (HE) staining and α-actinin immunofluorescent staining were used to measure cardiomyocyte size. Cardiac fibrosis was evaluated by Masson's trichrome staining. The expression of atrial natriuretic polypeptide (ANP) and brain natriuretic polypeptide (BNP) were determined by quantitative real time PCR (qRT-PCR). Western blot was applied to examine the expression of peroxisome proliferator-activated receptor gamma (PPARγ), PPARγ coactivator-1α (PGC-1α), fibrosis-related and apoptosis-related proteins.

Results: We found that CRP could significantly attenuate ISO-induced cardiac dysfunction, inhibit cardiac pathological hypertrophy and alleviate myocardial fibrosis and apoptosis. Mechanistically, the downregulation of PPARγ and PGC-1α in ISO-injected mice hearts and ISO-treated NRVMs could be reversed by CRP treatment. The beneficial effects of CRP against ISO-induced HF were abolished by PPARγ inhibitor (T0070907), suggesting that CRP-mediated PPARγ upregulation was essential for the preventive effect of CRP on ISO-induced cardiac dysfunction.

Conclusions: In conclusion, our study demonstrated that CRP attenuates ISO-induced cardiac remodeling via PPARγ activation, which represents a new application for CRP in the prevention of chronic HF.
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http://dx.doi.org/10.21037/atm-20-2200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723657PMC
November 2020

Entropy subspace separation-based clustering for noise reduction (ENCORE) of scRNA-seq data.

Nucleic Acids Res 2021 02;49(3):e18

Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.

Single-cell RNA sequencing enables us to characterize the cellular heterogeneity in single cell resolution with the help of cell type identification algorithms. However, the noise inherent in single-cell RNA-sequencing data severely disturbs the accuracy of cell clustering, marker identification and visualization. We propose that clustering based on feature density profiles can distinguish informative features from noise. We named such strategy as 'entropy subspace' separation and designed a cell clustering algorithm called ENtropy subspace separation-based Clustering for nOise REduction (ENCORE) by integrating the 'entropy subspace' separation strategy with a consensus clustering method. We demonstrate that ENCORE performs superiorly on cell clustering and generates high-resolution visualization across 12 standard datasets. More importantly, ENCORE enables identification of group markers with biological significance from a hard-to-separate dataset. With the advantages of effective feature selection, improved clustering, accurate marker identification and high-resolution visualization, we present ENCORE to the community as an important tool for scRNA-seq data analysis to study cellular heterogeneity and discover group markers.
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http://dx.doi.org/10.1093/nar/gkaa1157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7897472PMC
February 2021

Rapid DDTs degradation by thermally activated persulfate in soil under aerobic and anaerobic conditions: Reductive radicals vs. oxidative radicals.

J Hazard Mater 2021 01 26;402:123557. Epub 2020 Jul 26.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China.

Persulfate (PS)-based oxidation technologies have been extensively employed for contaminant remediation, but the mechanisms of PS-mediated pollutant removal in soil under anaerobic conditions have not been fully explored. In this study, the degradation of DDTs (DDT and DDE) by thermally activated PS in a real contaminated soil was investigated. It was found that DDTs degradation could be achieved under both aerobic and anaerobic conditions, and anaerobic conditions were comparatively more efficient. Further analyses based on electron paramagnetic resonance (EPR), free radical quenching studies and degradation product identification showed that, oxidative radicals (SO/OH) were the major species responsible for DDTs degradation under aerobic conditions, while both reductive (persulfate radical SO) and oxidative radicals were involved under anaerobic conditions. Furthermore, reductive degradation of DDT could also be observed in the presence of ethanol (EtOH) due to the formation of EtOH radical. In addition, DDT degradation was hardly affected by anions such as HCO and Cl at anaerobic conditions while its degradation was greatly inhibited by these anions under aerobic conditions. This study significantly improved our knowledge of PS-mediated degradation processes of DDTs and provided new insight into soil remediation by in-situ chemical oxidation at different oxygen status.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123557DOI Listing
January 2021

Synergy between Iron and Selenide on FeSe(111) Surface Driving Peroxymonosulfate Activation for Efficient Degradation of Pollutants.

Environ Sci Technol 2020 12 18;54(23):15489-15498. Epub 2020 Nov 18.

Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, P. R. China.

In this study, iron selenide nanoparticles (FeSe) were synthesized and applied in Fenton-like reactions for degradation of pollutants. It was found that FeSe exerts excellent catalytic reactivity toward different oxidants including peroxymonosulfate (PMS), peroxydisulfate, and HO, which can degrade a wide range of pollutants such as 2,4,4'-trichlorobiphenyl, bisphenol A, sulfamethoxazole, chlortetracycline, and perfluorooctanoic acid, with the degradation efficiency and TOC removal of pollutants reaching 55-95 and 20.3-50.9%, respectively. The mechanism of PMS activation by FeSe was elucidated, and the synergistic effect between Fe and Se for PMS activation was discovered to be the dominant catalytic mechanism, as evidenced by free-radical quenching, electron paramagnetic resonance, and density functional theory studies. Briefly, the Fe(II) site on the FeSe surface (111) accounted for PMS activation, while the reducing Se species on the surface not only acted as an electron donor contributing to Fe(II) regeneration but also produced Se vacancies further facilitating Fe(II) regeneration to improve the performance of PMS activation. In addition, FeSe exhibited high catalytic activity and stability for PMS activation with different pH, and can degrade PCBs efficiently in the presence of anions, natural organic matter water matrices or in complex soil eluents. This study presents the development and evaluation of FeSe as a novel and highly efficient activator that exhibits promise for practical applications for the degradation of pollutants in wastewater and soil wash eluent with Fenton-like reactions.
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http://dx.doi.org/10.1021/acs.est.0c06091DOI Listing
December 2020

Current Studies and Future Directions of Exercise Therapy for Muscle Atrophy Induced by Heart Failure.

Front Cardiovasc Med 2020 23;7:593429. Epub 2020 Oct 23.

Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, School of Life Science, Shanghai University, Shanghai, China.

Muscle atrophy is a common complication of heart failure. At present, there is no specific treatment to reverse the course of muscle atrophy. Exercise training, due to the safety and easy operation, is a recommended therapy for muscle atrophy induced by heart failure. However, the patients with muscle atrophy are weak in mobility and may not be able to train for a long time. Therefore, it is necessary to explore novel targets of exercise protection for muscle atrophy, so as to improve the quality of life and survival rate of patients with muscular atrophy induced by heart failure. This article aims to review latest studies, summarize the evidence and limitations, and provide a glimpse into the future of exercise for the treatment of muscle atrophy induced by heart failure. We wish to highlight some important findings about the essential roles of exercise sensors in muscle atrophy induced by heart failure, which might be helpful for searching potential therapeutic targets for muscle wasting induced by heart failure.
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http://dx.doi.org/10.3389/fcvm.2020.593429DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7644508PMC
October 2020
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