Publications by authors named "Shanshan Wei"

67 Publications

miR-20a Overexpression in Adipose-Derived Mesenchymal Stem Cells Promotes Therapeutic Efficacy in Murine Lupus Nephritis by Regulating Autophagy.

Stem Cells Int 2021 21;2021:3746335. Epub 2021 Oct 21.

Department of Dermatology, Nanfang Hospital, Southern Medical University, China.

Objective: Lupus nephritis is the most common and severe complication of systemic lupus erythematosus. The aim of our study was to investigate the efficacy of miR-20a overexpressing adipose-derived stem cell (ADSC) transplantation in murine lupus nephritis (LN) and explore potential molecular mechanisms.

Methods: Mouse ADSCs were transfected with a miR-20a lentiviral vector to obtain miR-20a overexpression ADSCs (miR-20a-ADSCs). We first observed the influence of miR-20a on ADSC viability and apoptosis . B6.MRL/lpr mice were administered ADSC/miR-20a-ADSC intravenously every week from age 30 to 33 weeks, and the lupus and normal control groups received PBS on the same schedule.

Results: miR-20a expression increased in miR-20a-ADSC-derived exosomes, and miR-20a overexpression promoted ADSC proliferation and inhibited apoptosis. Compared with ADSCs, miR-20a-ADSC treatment significantly improved serologic and histologic abnormalities, as evidenced by reduced serum creatinine, anti-dsDNA antibody, 24 h urine protein levels, nephritis scores, and C3/IgG deposits. Furthermore, miR-20a-ADSC treatment resulted in downregulated Akt, mTOR, and p62 expression and upregulated miR-20a, Beclin 1, and LC3 II/I expression compared with ADSC treatment. After treatment with miR-20a-ADSC, a significant increase in the number of autophagosomes within podocytes was observed, along with upregulated expression of podocin and nephrin, compared with the ADSC group.

Conclusions: miR-20a-ADSC transplantation prevents the development of lupus nephritis and significantly ameliorates already-established disease, and its mechanism is related to autophagy by targeting the miR-20a-regulated mTOR pathway.
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http://dx.doi.org/10.1155/2021/3746335DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8553505PMC
October 2021

848 kHz repetition-rate narrowband dissipative soliton ps-pulsed Figure-9 fiber laser.

Opt Express 2021 Jul;29(15):23967-23975

In this paper, we study the limitations of decreasing the repetition rate for the narrowband dissipative soliton picosecond (ps) pulsed Figure-9 fiber laser with periodically saturable absorber (SA), and demonstrate how to decrease the repetition rate of this kind of fiber laser. By asymmetrically increasing the passive fiber length of nonlinear amplifying loop mirror (NALM) to lower SA saturation power, Q-switching instability can be avoided, thus effectively reducing the repetition rate of ps pulses. To combat noise-like pulse caused by excessive reduction of SA saturation power, we invoke the non-reciprocal output characteristics of periodic SA, and combined with increasing the intracavity fiber length outside the SA, we further reduce the laser repetition rate. Repetition rates for ∼10 and ∼20 ps pulses are reduced to 1.7 MHz and 848 kHz, respectively, which are, to the best of our knowledge, the lowest repetition rates of Figure-9 lasers reported thus far.
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http://dx.doi.org/10.1364/OE.432955DOI Listing
July 2021

Network Pharmacology Prediction and Molecular Docking-Based Strategy to Discover the Potential Pharmacological Mechanism of Huai Hua San Against Ulcerative Colitis.

Drug Des Devel Ther 2021 28;15:3255-3276. Epub 2021 Jul 28.

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, People's Republic of China.

Background: Huai Hua San (HHS), a famous Traditional Chinese Medicine (TCM) formula, has been widely applied in treating ulcerative colitis (UC). However, the interaction of bioactives from HHS with the targets involved in UC has not been elucidated yet.

Aim: A network pharmacology-based approach combined with molecular docking and in vitro validation was performed to determine the bioactives, key targets, and potential pharmacological mechanism of HHS against UC.

Materials And Methods: Bioactives and potential targets of HHS, as well as UC-related targets, were retrieved from public databases. Crucial bioactive ingredients, potential targets, and signaling pathways were acquired through bioinformatics analysis, including protein-protein interaction (PPI), as well as the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Subsequently, molecular docking was carried out to predict the combination of active compounds with core targets. Lastly, in vitro experiments were conducted to further verify the findings.

Results: A total of 28 bioactive ingredients of HHS and 421 HHS-UC-related targets were screened. Bioinformatics analysis revealed that quercetin, luteolin, and nobiletin may be potential candidate agents. JUN, TP53, and ESR1 could become potential therapeutic targets. PI3K-AKT signaling pathway might play an important role in HHS against UC. Moreover, molecular docking suggested that quercetin, luteolin, and nobiletin combined well with JUN, TP53, and ESR1, respectively. Cell experiments showed that the most important ingredient of HHS, quercetin, could inhibit the levels of inflammatory factors and phosphorylated c-Jun, as well as PI3K-Akt signaling pathway in LPS-induced RAW264.7 cells, which further confirmed the prediction by network pharmacology strategy and molecular docking.

Conclusion: Our results comprehensively illustrated the bioactives, potential targets, and molecular mechanism of HHS against UC. It also provided a promising strategy to uncover the scientific basis and therapeutic mechanism of TCM formulae in treating diseases.
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http://dx.doi.org/10.2147/DDDT.S319786DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8326529PMC
July 2021

Recent Progress in Environmental Toxins-Induced Cardiotoxicity and Protective Potential of Natural Products.

Front Pharmacol 2021 8;12:699193. Epub 2021 Jul 8.

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.

Humans are unconsciously exposed to environmental toxins including heavy metals as well as various pesticides, which have deleterious effects on human health. Accumulating studies pointed out that exposure to environmental toxins was associated with various cardiopathologic effects. This review summarizes the main mechanisms of cardiotoxicity induced by environmental toxins (cadmium, arsenic and pesticides) and discusses the potential preventive effects of natural products. These findings will provide a theoretical basis and novel agents for the prevention and treatment of environmental toxins-induced cardiotoxicity. Furthermore, the limitations of current studies, future needs and priorities are discussed.
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http://dx.doi.org/10.3389/fphar.2021.699193DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8296636PMC
July 2021

Cordyceps sinensis aqueous extract regulates the adaptive immunity of mice subjected to Co γ irradiation.

Phytother Res 2021 Sep 8;35(9):5163-5177. Epub 2021 Jul 8.

School of Pharmacy, Jiangxi University of Traditional Chinese Medicine, Nanchang, China.

Cordyceps sinensis (CS) is a traditional Chinese medicine that is known for treating various diseases, and particularly for exerting therapeutic effects in immune disorders. The adaptive immunoregulatory effects of CS aqueous extract (CSAE) on γ-irradiated mice have not been reported previously. The study aimed to evaluate the therapeutic effects of CSAE in mice immunosuppressed by irradiation. We observed that CSAE administration significantly increased body weight and spleen index, as well as the number of white blood cells, lymphocytes, and platelets in peripheral blood, T and B lymphocytes in spleen tissue, and total serum immunoglobulins in irradiated mice, whereas total serum pro-inflammatory cytokine levels were decreased. Collectively, CSAE maintained the structural integrity of spleen tissue and repaired its damage in irradiated mice as shown by hematoxylin and eosin staining, and decreased the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive splenocytes. Mechanistically, CSAE upregulated Bcl-2, and downregulated Bax and cleaved caspase-3 in spleen of irradiated mice. However, there were no significant differences in red blood cells and neutrophils in different groups. The results revealed that CSAE had protective effects against irradiation-induced immunosuppression, which was likely associated with an antiapoptotic effect and the regulation of adaptive immunity.
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http://dx.doi.org/10.1002/ptr.7186DOI Listing
September 2021

Corrigendum to "Antioxidant Effect of Polysaccharides in D-Galactose-Induced Heart Aging Mice".

Biomed Res Int 2021 3;2021:9806412. Epub 2021 Jun 3.

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China.

[This corrects the article DOI: 10.1155/2021/6688855.].
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http://dx.doi.org/10.1155/2021/9806412DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8203348PMC
June 2021

Periconceptional folate and gestational diabetes mellitus: a systematic review and meta-analysis of cohort studies.

J Matern Fetal Neonatal Med 2021 May 25:1-10. Epub 2021 May 25.

Department of Clinical Laboratory, Shenzhen Baoan Women's and Children's Hospital, Jinan University, Shenzhen, China.

Objective: To examine the relationship between periconceptional folate exposure and risk of gestational diabetes mellitus (GDM).

Methods: Several electronic databases, including PubMed, Embase, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), and Cochrane Library, were searched for all relevant cohort studies by January 2021. Studies on relationship between folate exposure (intake or status) and GDM risk were included. Quality of included studies was assessed using Newcastle-Ottawa Scale. Random effects meta-analysis was performed to estimate overall odds ratio (OR) and 95% confidence intervals (CIs) by Stata software (Stata Corp., College Station, TX).

Results: Ten cohort studies with 40,244 pregnancies were eligible for quantitative meta-analysis. Significant association was observed between folate exposure and risk of GDM (OR = 1.24, =.036, 95% CI: 1.01-1.52). Subgroup analysis revealed that periconceptional folate exposure of population in China (OR = 1.35, 95% CI: 1.09-1.67) but not in western countries, folate exposure during pregnancy (OR = 1.49, 95% CI: 1.22-1.81) but not before pregnancy, and internal folate exposure (OR = 1.36, 95% CI: 1.10-1.67), were significantly associated with increased GDM risk.

Conclusions: Overall, periconceptional folate exposure is positively associated with GDM risk, especially the exposure during pregnancy and exposure in Chinese populations.
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http://dx.doi.org/10.1080/14767058.2021.1929158DOI Listing
May 2021

NLRP3 Inflammasome: A Promising Therapeutic Target for Drug-Induced Toxicity.

Front Cell Dev Biol 2021 12;9:634607. Epub 2021 Apr 12.

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.

Drug-induced toxicity, which impairs human organ function, is a serious problem during drug development that hinders the clinical use of many marketed drugs, and the underlying mechanisms are complicated. As a sensor of infections and external stimuli, nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome plays a key role in the pathological process of various diseases. In this review, we specifically focused on the role of NLRP3 inflammasome in drug-induced diverse organ toxicities, especially the hepatotoxicity, nephrotoxicity, and cardiotoxicity. NLRP3 inflammasome is involved in the initiation and deterioration of drug-induced toxicity through multiple signaling pathways. Therapeutic strategies via inhibiting NLRP3 inflammasome for drug-induced toxicity have made significant progress, especially in the protective effects of the phytochemicals. Growing evidence collected in this review indicates that NLRP3 is a promising therapeutic target for drug-induced toxicity.
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http://dx.doi.org/10.3389/fcell.2021.634607DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072389PMC
April 2021

Antioxidant Effect of Polysaccharides in D-Galactose-Induced Heart Aging Mice.

Biomed Res Int 2021 29;2021:6688855. Epub 2021 Mar 29.

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China.

polysaccharides (PSP), the extract of , are demonstrated to exhibit a wide range of pharmacological activities. A recent study reported that PSP alleviated the aging of the kidney and meninges. However, the effect of PSP on heart aging remains unclear. The present study is aimed at investigating the protection of PSP on D-galactose- (D-gal-) induced heart aging. Results showed that irregularly arranged cardiac muscle fibers were observed in heart tissues of D-gal-treated mice, and the levels of cardiac troponin T (cTnT), creatine kinase (CK), p21, and p53 were increased after D-gal treatment. D-gal-induced heart aging and injury can be attenuated by oral administration of PSP. Moreover, PSP also decreased reactive oxygen species (ROS) and malondialdehyde (MDA) and increased the level of superoxide dismutase (SOD) in the hearts of D-gal-treated mice. DNA damages and lipid peroxidation induced by oxidative stress were also inhibited by PSP as indicated by reduced levels of 8-hydroxydeoxyguanosine (8-OHdG) and 4-hydroxy-2-nonenal (4-HNE). Collectively, PSP attenuated D-gal-induced heart aging via inhibiting oxidative stress, suggesting that PSP might serve as a potential effective Chinese herbal active constituent for antiaging therapy.
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http://dx.doi.org/10.1155/2021/6688855DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024086PMC
May 2021

Severity analysis of road transport accidents of hazardous materials with machine learning.

Traffic Inj Prev 2021 13;22(4):324-329. Epub 2021 Apr 13.

School of Automobile, Chang'an University, Xi'an, China.

Objective: The aim of this study was to explore a suitable method for analyzing road transport accidents that involve hazardous materials and to explore the main factors that influence the occurrence of accidents of varying severity.

Methods: The 2015-2019 reported crash data from the Ministry of Transport of the People's Republic of China were obtained, and road transport crashes involving hazardous materials were extracted as the analysis data. The dataset was classified into three injury severity categories: property damage only (PDO), injured (INJ), and fatal (FAT). A statistical model and three machine learning-based models were developed: a random parameters logit model (RPLM), multilayer perceptron (MLP), decision tree C5.0 (C5.0) and support vector machine (SVM). The four models were trained/estimated using the training/estimation dataset, and the best model was used to model accidents of the three different severity levels. The main factors that influence the occurrence of accidents at each crash severity level were obtained.

Results: C5.0 had the best modeling performance. The direct accident form (DAF), indirect accident form (IAF) and road segment (RS) were determined to be the critical determinants of PDO accidents. The DAF, IAF, road type, RS and time had a substantial effect on INJ accidents. The DAF, IAF, hazardous material type (HMT) and road surface condition were important factors in the occurrence of FAT accidents.

Conclusions: Different data have unique characteristics, and the best modeling and analysis method should be chosen accordingly. The safety of road transport of hazardous materials in China is poor, and the losses caused by accidents are substantial. Strengthening the monitoring of travel speed and travel time; improving driver safety awareness, driving skills and the ability to mitigate emergencies; improving the configuration of vehicle safety equipment and the linkage with the control center and rescue center; improving the environmental differences between inside a tunnel and outside a tunnel; reducing the design of long downhill and steep slope sections; reducing the transport plan in unsafe environments; and improving the ability of road management to mitigate bad environments can be effective measures to reduce the severity of road transport accidents involving hazardous materials.
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http://dx.doi.org/10.1080/15389588.2021.1900569DOI Listing
July 2021

Shizukaol A exerts anti-inflammatory effect by regulating HMGB1/Nrf2/HO-1 pathway.

Phytomedicine 2021 Feb 17;82:153472. Epub 2021 Jan 17.

State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, People's Republic of China. Electronic address:

Background: Sarcandra glabra (Thunb.) Makino (Chloranthaceae) has a long history of being used in Traditional Chinese medicines (TCMs) to treat painful joints, fractures, arthritis, and other diseases caused by inflammation. It has been reported that lindenane-type sesquiterpenoid dimers are main anti-inflammatory ingredient of S. glabra. Meanwhile, shizukaol A, the precursor of these sesquiterpene dimers, possesses a good inhibitory effect on nitric oxide (NO) in our previous study. But its anti-inflammatory mechanism is still unclear.

Purpose: This study aimed to explore the possible anti-inflammatory mechanism and potential targets of shizukaol A in lipopolysaccharide (LPS)-induced RAW 264.7 cells.

Methods: The release of NO and inflammatory cytokines in LPS-stimulated RAW 264.7 cells were measured by Griess reagent and ELISA, respectively. The relevant proteins including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor kappa B (NF-κB) p65, High mobility group box 1 (HMGB1) were detected by western blot. Nuclear translocation of p65, HMGB1 and nuclear factor E2-related factor 2 (Nrf2) were examined by immunofluorescence. The level of reactive oxygen species (ROS) was tested by flow cytometry. The target of shizukaol A was investigated by molecular docking and Drug Affinity Responsive Target Stability (DARTS).

Results: Shizukaol A had a good inhibitory effect on NO with half maximal inhibitory concentration (IC) of 13.79 ± 1.11 μM. Shizukaol A could down-regulate the expression of iNOS and COX-2. Further studies demonstrated that shizukaol A can significantly inhibit phosphorylation and nuclear translocation of NF-κB. Meanwhile, shizukaol A decreased the level of ROS and enhanced the expression of heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1). Furthermore, shizukaol A up-regulated the expression of Nrf2 and its nuclear translocation. More importantly, shizukaol A could inhibit activation of HMGB1 by targeting HMGB1.

Conclusion: Shizukaol A inhibited inflammation by targeting HMGB1 to regulate the Nrf2/HO-1 signaling pathway. Thus, shizukaol A may be an attractive therapeutic candidate for inflammatory diseases.
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http://dx.doi.org/10.1016/j.phymed.2021.153472DOI Listing
February 2021

Systemic sclerosis and risk of cardiovascular disease: A PRISMA-compliant systemic review and meta-analysis of cohort studies.

Medicine (Baltimore) 2020 Nov;99(47):e23009

Department of Dermatology, Zhujiang Hospital, Southern Medical University.

Background: Systemic sclerosis (SSc) is an autoimmune disorder leading to extensive fibrosis and microvascular injury. Macrovascular disease is well documented in other autoimmune rheumatic diseases such as systemic lupus erythematosus and rheumatoid arthritis. However, the link is unclear between SSc and macrovascular disease, particularly atherosclerotic cardiovascular disease (CVD). This meta-analysis aimed to investigate the association between SSc and CVD.

Methods: A thorough literature search was conducted in the Cochrane, Embase, Medline, and PubMed to identify all cohort studies comparing the risk of CVD with and without SSc. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) of cardiovascular end points were calculated. The risk of bias of included studies was assessed by the Newcastle-Ottawa scale.

Results: Seven cohort studies with a total of 14,813 study participants were included. In a comparison of SSc patients versus non-SSc controls, the pooled HR for cardiovascular disease was 2.36 (95% CI 1.97-2.81); for peripheral vascular disease was 5.27 (95%CI 4.27-6.51); for myocardial infarction was 2.36 (95% CI 1.71-3.25); and for stroke was 1.52 (95% CI 1.18-1.96).

Conclusion: This meta-analysis revealed that SSc was associated with an increased risk of CVD. Clinicians who manage patients with SSc should be aware of the increased cardiovascular burden and undertake preventive measures.
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http://dx.doi.org/10.1097/MD.0000000000023009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7676589PMC
November 2020

An "on-off-on" selective fluorescent probe based on nitrogen and sulfur co-doped carbon dots for detecting Cu and GSH in living cells.

Anal Methods 2020 11 15;12(42):5110-5119. Epub 2020 Oct 15.

School of Chemistry and Life Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, P. R. China.

The abnormal level of Cu or GSH can cause variety of neurodegenerative diseases in humans. Thus, the selective and sensitive detection of Cu and GSH has inspired intensive research efforts in biological sample analysis fields. Herein, an "on-off-on" fluorescent probe based on nitrogen and sulfur co-doped carbon dots (N,S-CDs) has been successfully prepared for the detection of Cu and GSH. The "turn-off" process of fluorescence in the presence of Cu ions was induced by forming a non-luminescent ground state complex due to the interaction between surface groups of the probe and Cu ions. Moreover, the strong coordination between GSH and Cu could destroy the structure of the complex and restore the fluorescence to "turn-on". This fluorescent probe had excellent selectivity and high sensitivity toward Cu and GSH with the limits of detection (LODs) of 38 nM and 41 nM. More importantly, the as-prepared N,S-CDs served as an efficient fluorescent probe for not only detecting Cu ions in lake water and tap water, and GSH in BSA solution, but also sensing Cu and GSH in living cells. Therefore, these N,S-CDs could be considered as a promising fluorescence probe candidate for environmental monitoring and biological imaging.
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http://dx.doi.org/10.1039/d0ay01662dDOI Listing
November 2020

Plasma metabolomic profiling of repeated restraint stress in rats.

J Chromatogr B Analyt Technol Biomed Life Sci 2020 Dec 30;1160:122294. Epub 2020 Jul 30.

College of Basic Medical Sciences, Yunnan University of Chinese Medicine, Kunming 650500, Yunnan Province, China. Electronic address:

Exposure to repeated stress is associated with the occurrence and development of many prevalent diseases. Here, we evaluated the impact of a repeated restraint stress (RRS) paradigm on male Wistar rats and compared global plasma metabolites in stressed and unstressed rats using an ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS) approach and multivariate statistical analysis. The data showed that ten days of RRS induced weight loss and anxiety-like behavior, possibly through elevating plasma corticosterone levels in rats. Different metabolic characteristics were found between the two groups. Seventeen differential metabolites were identified and considered as potential biomarkers in the stress process, including histidine metabolism, neurotransmitter synthesis, and bile acid metabolism. Furthermore, l-carnosine, an identified metabolite, was examined in the same model and found to attenuate weight loss and anxiety-like behavior in RRS rats. Hence, these findings describe the metabolomic profiling of repeated stress and provide new insights into the pathophysiological mechanism of stress-induced deflections and potential pharmacological interventions.
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http://dx.doi.org/10.1016/j.jchromb.2020.122294DOI Listing
December 2020

A Deep Learning Model for Automated Sub-Basal Corneal Nerve Segmentation and Evaluation Using In Vivo Confocal Microscopy.

Transl Vis Sci Technol 2020 06 18;9(2):32. Epub 2020 Jun 18.

Department of Ophthalmology, Peking University Third Hospital, Beijing, China.

Purpose: The purpose of this study was to establish a deep learning model for automated sub-basal corneal nerve fiber (CNF) segmentation and evaluation with in vivo confocal microscopy (IVCM).

Methods: A corneal nerve segmentation network (CNS-Net) was established with convolutional neural networks based on a deep learning algorithm for sub-basal corneal nerve segmentation and evaluation. CNS-Net was trained with 552 and tested on 139 labeled IVCM images as supervision information collected from July 2017 to December 2018 in Peking University Third Hospital. These images were labeled by three senior ophthalmologists with ImageJ software and then considered ground truth. The areas under the receiver operating characteristic curves (AUCs), mean average precision (mAP), sensitivity, and specificity were applied to evaluate the efficiency of corneal nerve segmentation. The relative deviation ratio (RDR) was leveraged to evaluate the accuracy of the corneal nerve fiber length (CNFL) evaluation task.

Results: The model achieved an AUC of 0.96 (95% confidence interval [CI] = 0.935-0.983) and an mAP of 94% with minimum dice coefficient loss at 0.12. For our dataset, the sensitivity was 96% and specificity was 75% in the CNF segmentation task, and an RDR of 16% was reported in the CNFL evaluation task. Moreover, the model was able to segment and evaluate as many as 32 images per second, much faster than skilled ophthalmologists.

Conclusions: We established a deep learning model, CNS-Net, which demonstrated a high accuracy and fast speed in sub-basal corneal nerve segmentation with IVCM. The results highlight the potential of the system in assisting clinical practice for corneal nerves segmentation and evaluation.

Translational Relevance: The deep learning model for IVCM images may enable rapid segmentation and evaluation of the corneal nerve and may provide the basis for the diagnosis and treatment of ocular surface diseases associated with corneal nerves.
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http://dx.doi.org/10.1167/tvst.9.2.32DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7414615PMC
June 2020

Short-Term Intravenous Infusion of Cyclophosphamide in the Treatment of Refractory Pemphigus Vulgaris: A Retrospective Study.

Dermatology 2021 19;237(2):185-190. Epub 2020 Aug 19.

Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China,

Background: Pemphigus is an autoimmune disease of the skin and mucous membranes. Glucocorticoids have been the most effective drug for the treatment of pemphigus; however, some patients are insensitive to glucocorticoid therapy. Cyclophosphamide has been extensively used in the treatment of pemphigus.

Objectives: To observe and evaluate the efficacy and safety of high-dose glucocorticoid with weekly intravenous cyclophosphamide in the treatment of refractory pemphigus vulgaris insensitive to glucocorticoids.

Methods: Clinical data of 19 patients with refractory pemphigus vulgaris (insensitive to glucocorticoid) who were treated with high-dose glucocorticoids(1.5 mg/kg/day prednisone) and weekly intravenous infusion of cyclophosphamide, and 24 patients who were sensitive to glucocorticoid therapy received a medium dose of glucocorticoid alone (1 mg/kg/day prednisone) were retrospectively analyzed.

Results: By the time the disease was brought under control, the average total dose of cyclophosphamide was 2.02 g. Comparison between the glucocorticoid-insensitive and glucocorticoid-sensitive groups showed that the average time to disease control was 2.68 vs. 2 weeks, and the average daily dosage of steroid was 1.33 ± 0.53 vs. 0.90 ± 0.28 mg/kg. At the 12- and 18-month follow-ups, the recurrence rate of the glucocorticoid-insensitive group was significantly lower than that of the sensitive group (5.3 vs. 37.5%, 15.8 vs. 45.8%). No serious adverse reactions were observed.

Conclusion: High-dose glucocorticoid plus weekly intravenous infusion of cyclophosphamide safely, effectively, and rapidly controlled the conditions of the patients with refractory pemphigus who were insensitive to glucocorticoids, shortened the duration of hospitalization, avoided the risk of complications that could be caused by further increasing the dose of glucocorticoids (>1.5 mg/kg/day), and lowered the recurrence rate within 18 months.
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http://dx.doi.org/10.1159/000508671DOI Listing
November 2021

Evaluation of objective visual quality in dry eye disease and corneal nerve changes.

Int Ophthalmol 2020 Nov 2;40(11):2995-3004. Epub 2020 Jul 2.

Department of Ophthalmology, Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, 100191, China.

Purpose: To explore objective visual quality in dry eye diseases (DED) and the correlation between corneal nerves and objective visual quality.

Methods: Ninety-eight eyes of 49 patients with DED were included. Each patient was evaluated with the ocular surface disease index (OSDI), eyelid margin signs and meibomian gland assessments; corneal staining; tear film breakup time (TBUT); tear meniscus height (TMH); in vivo confocal microscopic (IVCM); objective visual quality including the objective scatter index (OSI), mean objective scattering index (mOSI), modulation transfer function (MTF) cutoff value and Strehl ratio.

Results: A significant correlation was found between the OSDI and mOSI (r = 0.422, p = 0.005), MTF cutoff value (r = - 0.355, p = 0.020), and Strehl ratio (r = - 0.446, p = 0.003). The OSI was significantly correlated with TBUTf (r = - 0.213, p = 0.042). The mOSI, MTF cutoff value, Strehl ratio were correlated with eyelid margin signs and meibomian assessments. Additionally, there was a statistically significant correlation between corneal nerve length and the mOSI (r = - 0.239, p = 0.037), OSI (r = - 0.294, p = 0.028), MTF cutoff value(r = 0.282, p = 0.012), and Strehl ratio (r = 0.299, p = 0.008).

Conclusions: Our study explored that objective visual quality was correlated with clinical symptoms and signs in DED patients. Furthermore, for the first time, our study explored the relationship between corneal nerves and objective visual quality and discovered that longer and wider corneal nerves were associated with better objective visual quality, which suggested that nerve changes may be a factor that related to poor visual quality in DED patients.
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http://dx.doi.org/10.1007/s10792-020-01483-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7550365PMC
November 2020

Involvement of ROS/NLRP3 Inflammasome Signaling Pathway in Doxorubicin-Induced Cardiotoxicity.

Cardiovasc Toxicol 2020 10;20(5):507-519

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, 410011, Hunan, China.

Doxorubicin (Dox) is widely used in cancer therapy, but the clinical application is limited by its cardiotoxicity. The underlying mechanism of Dox-induced cardiotoxicity remains unclear. Present study aimed to evaluate the role of NLRP3 inflammasome in Dox-induced cardiotoxicity. The NLRP3 inflammasome was activated in the myocardium of Dox-treating (5 mg/kg, once every other day, cumulative dosage to 15 mg/kg and sacrificed after 2 days of last Dox injection) C57BL/6 mice as shown by the up-regulation of NLRP3 and Caspase-1 p20. Dox (1 μM for 48 h) induced the apoptosis of H9c2 cells and primary cardiomyocytes concomitantly with up-regulation of NLRP3, ASC and Caspase-1 p20 expressions, as well as the increased IL-1β secretion, suggesting the activation of NLRP3 inflammasome. These effects of Dox on H9c2 cells and primary cardiomyocytes can be reversed by MCC950, a specific inhibitor of NLRP3. In view of the key role of ROS on the Dox-induced cardiotoxicity, the relationship between ROS and NLRP3 was further investigated. The ROS level was increased in myocardium, H9c2 cells and primary cardiomyocytes after treating with Dox. Decreasing ROS level by NAC can inhibit the NLRP3 inflammasome activation, secretion of IL-1β and apoptosis in Dox-treating H9c2 cells and primary cardiomyocytes. Collectively, this study reveals a crucial role of ROS/NLRP3-associated inflammasome activation in Dox-induced cardiotoxicity, and NLRP3 inflammasome may represent a new therapeutic target for Dox-induced cardiotoxicity.
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http://dx.doi.org/10.1007/s12012-020-09576-4DOI Listing
October 2020

The application and extension of the theory of planned behavior to an analysis of delivery riders' red-light running behavior in China.

Accid Anal Prev 2020 Sep 26;144:105640. Epub 2020 Jun 26.

School of Automobile, Chang'an University, Xi'an, Shaanxi, China.

Delivery riders, an occupation that has emerged from China's booming E-commerce industry, have attracted widespread attention due to their red-light running (RLR) and high accident rates. This study aimed to utilize the theory of planned behavior (TPB) to investigate the psychological characteristics of delivery riders' RLR intentions. A survey questionnaire was designed to collect data, including information regarding the extended variables, the basic components of the TPB and demographic characteristics. The survey was conducted in Xi'an, and 228 complete questionnaires were collected. Structural equation modeling was used to examine the data, and a multiple group analysis of the demographic variables was conducted. The results showed that the expanded TPB model had a better model fit and higher variance explanation than the original TPB model. Extended constructs, i.e., conformity tendency (CT) and the traffic environment (TE), were significant predictors, and attitude was the strongest predictor of all the examined variables related to RLR intentions. Finally, the path parameters of the expended TPB model were adapted for different demographic groups, and some differential effects were also found. These results could provide a basis for the design of intervention measures and safety education schemes by delivery platforms and traffic management departments to reduce RLR behavior among delivery riders.
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http://dx.doi.org/10.1016/j.aap.2020.105640DOI Listing
September 2020

Molecular Mechanisms of Cardiomyocyte Death in Drug-Induced Cardiotoxicity.

Front Cell Dev Biol 2020 3;8:434. Epub 2020 Jun 3.

Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha, China.

Homeostatic regulation of cardiomyocytes plays a crucial role in maintaining the normal physiological activity of cardiac tissue. Severe cardiotoxicity results in cardiac diseases including but not limited to arrhythmia, myocardial infarction and myocardial hypertrophy. Drug-induced cardiotoxicity limits or forbids further use of the implicated drugs. Such drugs that are currently available in the clinic include anti-tumor drugs (doxorubicin, cisplatin, trastuzumab, etc.), antidiabetic drugs (rosiglitazone and pioglitazone), and an antiviral drug (zidovudine). This review focused on cardiomyocyte death forms and related mechanisms underlying clinical drug-induced cardiotoxicity, including apoptosis, autophagy, necrosis, necroptosis, pryoptosis, and ferroptosis. The key proteins involved in cardiomyocyte death signaling were discussed and evaluated, aiming to provide a theoretical basis and target for the prevention and treatment of drug-induced cardiotoxicity in the clinical practice.
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http://dx.doi.org/10.3389/fcell.2020.00434DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7283551PMC
June 2020

Antifungal activity of peptide MSI-1 against Cryptococcus neoformans infection in vitro and in murine cryptococcal meningoencephalitis.

Peptides 2020 08 3;130:170334. Epub 2020 Jun 3.

School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, PR China. Electronic address:

The development of novel antifungal agents with high efficacy, low drug tolerance and few side effects is urgent. MSI-1 (GIWKFLKKAKKFWK-NH), a cationic antimicrobial peptide, may be an attractive antifungal agent because of its structural characteristics, perfect stability against pH and high-temperature/salt, low toxicity towards mammalian cells and low potential for emergence of drug tolerance. In this study, the antifungal activity of MSI-1 in vitro and in a murine model of cryptococcal meningoencephalitis was evaluated. Zeta potential assay, flow cytometry, fluorescence microscope, transmission electron microscopy and microscale thermophoresis were performed to clarify the mechanisms underlying MSI-1 against C. neoformans. The results showed that MSI-1 exerted effective anti-cryptococcal activity in vitro, with MICs of 8-16 μg/mL and MFCs of 8-32 μg/mL, and in a C neoformans-infected mouse model, with significantly improved animal survival, decreased production of pro-inflammatory cytokines and alleviated lung injury, because the potent and rapid fungicidal activity of MSI-1 could effectively eliminate fungal counts in mouse organs. We confirmed that the positively charged peptide bound to C. neoformans by electrostatic attraction after interacting with glucuronoxylomannan (the primary component of C. neoformans capsule). Subsequently, MSI-1 increased the membrane fluidity of fungal cells and the cell membrane permeability, causing destabilized membrane integrity and leading to the final death of fungi. Collectively, MSI-1 possessed potent anti-cryptococcal activity via its notable membrane disruption effect and may be a potential candidate for use in antifungal infection induced by C. neoformans, especially azole-resistant cryptococcus.
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http://dx.doi.org/10.1016/j.peptides.2020.170334DOI Listing
August 2020

Therapeutic Effect of Intense Pulsed Light (IPL) Combined with Meibomian Gland Expression (MGX) on Meibomian Gland Dysfunction (MGD).

J Ophthalmol 2020 13;2020:3684963. Epub 2020 Apr 13.

Department of Ophthalmology, Beijing Key Laboratory of Restoration of Damaged Ocular Nerves, Peking University Third Hospital, Beijing 100191, China.

Purpose: Our study aimed to evaluate the efficiency of intense pulsed light (IPL) combined with meibomian gland expression (MGX) in treating meibomian gland dysfunction (MGD).

Methods: This study was a prospective interventional study. A total of 53 patients were included in the study and received a series of three treatments at an interval of 3-4 weeks. Follow-up examinations were completed 4 weeks after the last treatment. The Ocular Surface Disease Index (OSDI) questionnaire, tear meniscus height (TMH), tear break-up time (TBUT), slit-lamp examinations, and in vivo confocal microscopy (IVCM) were recorded before and after treatment. Additionally, an artificial intelligence automated software program was applied in our study for corneal nerve analysis.

Results: The OSDI score was significantly reduced after the IPL treatment compared with baseline ( < 0.001). Meibomian gland assessment scores, including meibum quality and expressibility, eyelid margin abnormalities, and corneal staining, significantly decreased after treatment ( < 0.05). Moreover, the corneal nerve fiber length (CNFL) significantly increased after the treatment ( < 0.001).

Conclusion: Intense pulsed light (IPL) combined with MGX is an effective treatment for MGD, and neurotrophism could be one of the mechanisms of IPL.
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http://dx.doi.org/10.1155/2020/3684963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7174928PMC
April 2020

Tumor microenvironment-responsive polydopamine-based core/shell nanoplatform for synergetic theranostics.

J Mater Chem B 2020 05;8(18):4056-4066

Department of Radiology, Second Hospital of Jilin University, Changchun, 130041, P. R. China.

Theranostic agents that integrate diagnostic and therapeutic modalities have drawn extensive attention due to their ability to deliver real-time imaging-guided tumor treatment. Herein, a novel core-shell polydopamine (PDA)-based theranostic agent ([email protected]) was fabricated via a two-step strategy. Upon 808 nm and 1064 nm laser irradiation, this agent exhibited high photothermal conversion efficiencies of 29% and 41%, respectively. After endocytosis into tumor cells, the TA-Fe shell of [email protected] gradually disintegrated in the weakly acidic tumor microenvironment (TME), and released the TA as an acidity-activated reductant that could reduce Fe3+ to Fe2+. Subsequently, the generated Fe2+ reacted with H2O2 to generate toxic hydroxyl radicals (˙OH) via the Fenton reaction, which induced the apoptosis of tumor cells and achieved the chemodynamic therapy (CDT). The heat produced by photothermal therapy (PTT) accelerated the ˙OH generation to achieve a synergetic effect of CDT/PTT. In vivo tumor-xenograft imaging and therapeutic assays demonstrated obvious contrast enhancement at the tumor site in the T1/T2-weighted MR imaging and efficient tumor suppression achieved after the intravenous injection of this agent because of the enhanced permeation and retention (EPR) effect. This study offered a new strategy to design an "all-in-one" nanoplatform for T1/T2 MR imaging-guided synergistic cancer treatment of CDT/PTT.
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http://dx.doi.org/10.1039/d0tb00248hDOI Listing
May 2020

A Label-Free Immunosensor Based on Graphene Oxide/FeO/Prussian Blue Nanocomposites for the Electrochemical Determination of HBsAg.

Biosensors (Basel) 2020 Mar 14;10(3). Epub 2020 Mar 14.

College of Electronic Engineering and Automation, Guilin University of Electronic Technology, Guilin 541004, China.

In this article, a highly sensitive label-free immunosensor based on a graphene oxide (GO)/FeO/Prussian blue (PB) nanocomposite modified electrode was developed for the determination of human hepatitis B surface antigen (HBsAg). In this electrochemical immunoassay system, PB was used as a redox probe, while GO/FeO/PB nanocomposites and AuNPs were prepared and coated on screen-printed electrodes to enhance the detection sensitivity and to immobilize the hepatitis B surface antibody (HBsAb). The immunosensor was fabricated based on the principle that the decrease in peak currents of PB is proportional to the concentration of HBsAg captured on the modified immunosensor. The experimental results revealed that the immunosensor exhibited a sensitive response to HBsAg in the range of 0.5 pg·mL to 200 ng·mL, and with a low detection limit of 0.166 pg·mL (S/N = 3). Furthermore, the proposed immunosensor was used to detect several clinical serum samples with acceptable results, and it also showed good reproducibility, selectivity and stability, which may have a promising potential application in clinical immunoassays.
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http://dx.doi.org/10.3390/bios10030024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7146221PMC
March 2020

A sensitive "ON-OFF" fluorescent probe based on carbon dots for Fe detection and cell imaging.

Analyst 2020 Mar;145(6):2357-2366

School of Chemistry and Life Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, P. R. China. and Advanced Institute of Materials Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, P. R. China.

Fe2+ is a trace metal ion required by the human body, and its abnormal metabolism can cause serious diseases. Herein, we report the development of a highly efficient "ON-OFF" fluorescent probe based on carbon dots (CDs), prepared by a simple one-step hydrothermal method. The CDs exhibited exceptional water dispersibility and stability, superior luminescence performance and low cytotoxicity. The fluorescence could be efficiently quenched by Fe2+ through an electronic transfer process. And under the optimized experimental conditions, this probe shows excellent selectivity and high sensitivity towards Fe2+ with a detection limit of 51 nmol. More interestingly, this probe could realize the visual detection of Fe2+ when Fe3+ and Cu2+ ions were efficiently shielded by tartaric acid in the presence of ascorbic acid. Furthermore, the developed fluorescent probe has been successfully applied for the detection of Fe2+ in tap water and BSA solution as well as for the biosensing of Fe2+ in living cells.
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http://dx.doi.org/10.1039/c9an02309gDOI Listing
March 2020

Polypyrrole-based double rare earth hybrid nanoparticles for multimodal imaging and photothermal therapy.

J Mater Chem B 2020 01;8(3):426-437

Jilin Province Key Laboratory of Carbon Fiber Development and Application, School of Chemistry and Life Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, P. R. China.

Nanotheranostic agents that can simultaneously provide real-time tracking and accurate treatment at tumor sites are playing an increasingly important role in medicine. Herein, a novel polypyrrole (PPy)-based theranostic agent containing double rare-earth elements ([email protected]/Dy NPs) was successfully synthesized via an integrated strategy combining biomineralization and oxidation polymerization. The obtained [email protected]/Dy NPs with a diameter of approximately 59.48 ± 6.12 nm exhibited excellent solubility, long-term stability, superior biocompatibility, and negligible toxicity. Importantly, due to its intrinsic paramagnetic and strong X-ray attenuation ability, this agent demonstrated brilliant imaging performance in both T1/T2-weighted magnetic resonance imaging (MRI) and X-ray computed tomography (CT) imaging in vitro and vivo. Additionally, with an excellent photothermal conversion efficiency (26.61%) upon irradiation by an 808 nm laser, this theranostic agent showed significant photothermal cytotoxicity against HeLa cells and 4T1 cells in vitro and antitumor efficacy through intravenous injection in vivo. Meanwhile, biodistribution and blood circulation were also used to explore its fate in vivo. In summary, this study highlighted the versatility and practicability of [email protected]/Dy NPs and also suggested that the agent may be a promising candidate for T1/T2-weighted MRI/CT tri-modal imaging guided photothermal cancer therapy.
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http://dx.doi.org/10.1039/c9tb02254fDOI Listing
January 2020

Ginsenoside Rb1 Promotes Motor Functional Recovery and Axonal Regeneration in Post-stroke Mice through cAMP/PKA/CREB Signaling Pathway.

Brain Res Bull 2020 01 9;154:51-60. Epub 2019 Nov 9.

Department of Neurology, Second Hospital of Hebei Medical University, 215 Hepingxi Road, Shijiazhuang, Hebei, 050000, PR China.

The central nervous system (CNS) has a poor self-repairing capability after injury because of the inhibition of axonal regeneration by many myelin-associated inhibitory factors. Therefore, ischemic stroke usually leads to disability. Previous studies reported that Ginsenoside Rb1 (GRb1) plays a role in neuronal protection in acute phase after ischemic stroke, but its efficacy in post-stroke and the underlying mechanism are not clear. Recent evidences demonstrated GRb1 promotes neurotransmitter release through the cAMP-depend protein kinase A (PKA) pathway, which is related to axonal regeneration. The present study aimed to determine whether GRb1 improves long-term motor functional recovery and promotes cortical axon regeneration in post-stroke. Adult male C57BL/6 mice were subjected to distal middle cerebral artery occlusion (dMCAO). GRb1 solution (5 mg/ml) or equal volume of normal saline was injected intraperitoneally for the first time at 24 h after surgery, and then daily injected until day 14. Day 3, 7, 14 and 28 after dMCAO were used as observation time points. Motor functional recovery was assessed with Rota-rod test and grid walking task. The expression of growth-associated protein 43 (GAP43) and biotinylated dextran amine (BDA) was measured to evaluate axonal regeneration. The levels of cyclic AMP (cAMP) and PKA were measured by Elisa, PKAc and phosphorylated cAMP response element protein (pCREB) were determined by western blot. Our results shown that GRb1 treatment improved motor function and increased the expression of GAP43 and BDA in ipsilesional and contralateral cortex. GRb1 significantly elevated cAMP and PKA, increased the protein expression of PKAc and pCREB. However, the effects of GRb1 were eliminated by H89 intervention (a PKA inhibitor). These results suggested that GRb1 improved functional recovery in post-stroke by stimulating axonal regeneration and brain repair. The underlying mechanism might be up-regulating the expression of cAMP/PKA/CREB pathway.
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http://dx.doi.org/10.1016/j.brainresbull.2019.10.006DOI Listing
January 2020

Cordycepin protects against β-amyloid and ibotenic acid-induced hippocampal CA1 pyramidal neuronal hyperactivity.

Korean J Physiol Pharmacol 2019 Nov 24;23(6):483-491. Epub 2019 Oct 24.

School of Pharmacy, Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi 330004, PR China.

Cordycepin exerts neuroprotective effects against excitotoxic neuronal death. However, its direct electrophysiological evidence in Alzheimer's disease (AD) remains unclear. This study aimed to explore the electrophysiological mechanisms underlying the protective effect of cordycepin against the excitotoxic neuronal insult in AD using whole-cell patch clamp techniques. β-Amyloid (Aβ) and ibotenic acid (IBO)-induced injury model in cultured hippocampal neurons was used for the purpose. The results revealed that cordycepin significantly delayed Aβ + IBO-induced excessive neuronal membrane depolarization. It increased the onset time/latency, extended the duration, and reduced the slope in both slow and rapid depolarization. Additionally, cordycepin reversed the neuronal hyperactivity in Aβ + IBO-induced evoked action potential (AP) firing, including increase in repetitive firing frequency, shortening of evoked AP latency, decrease in the amplitude of fast afterhyperpolarization, and increase in membrane depolarization. Further, the suppressive effect of cordycepin against Aβ + IBO-induced excessive neuronal membrane depolarization and neuronal hyperactivity was blocked by DPCPX (8-cyclopentyl-1,3-dipropylxanthine, an adenosine A receptor-specific blocker). Collectively, these results revealed the suppressive effect of cordycepin against the Aβ + IBO-induced excitotoxic neuronal insult by attenuating excessive neuronal activity and membrane depolarization, and the mechanism through the activation of AR is strongly recommended, thus highlighting the therapeutic potential of cordycepin in AD.
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http://dx.doi.org/10.4196/kjpp.2019.23.6.483DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6819905PMC
November 2019

Narrow-bandwidth actively Q-switched all-fiber laser by suppressing ASE gain self-saturation.

Opt Express 2019 Sep;27(19):27345-27353

This paper proposes and demonstrates a novel method to produce the narrow-bandwidth, narrow-pulse-width and high-repetition-rate pulses with actively Q-switched ring-cavity all-fiber lasers. By using a specially designed low-reflectivity cladding power stripper in the cavity, and inserting a length-optimized ytterbium-doped single-cladding fiber self-pumped by the backward amplified spontaneous emission (ASE) from the YDF to improve the amplification of the initial weak ASE feedback by the narrowband filter, the ASE gain self-saturation can be suppressed efficiently, and the lasing pulses can be established quickly within the opening time of Q-switch even operating for very high repetition-rate. With the proposed technique, watt-level Q-switched pulses with bandwidth and pulse width narrowed to 0.15 nm and 9 ns, and repetition rate up to 175 kHz are achieved.
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http://dx.doi.org/10.1364/OE.27.027345DOI Listing
September 2019

Maize Canopy Apparent Photosynthesis and C-Photosynthate Reallocation in Response to Different Density and N Rate Combinations.

Front Plant Sci 2019 19;10:1113. Epub 2019 Sep 19.

State Key Laboratory of Crop Biology, College of Agriculture, Shandong Agricultural University, Tai'an, China.

Appropriate planting density and nitrogen (N) supply are critical factors optimizing yield in crop cultivation. To advance the knowledge of maize plants under different density and N rate combinations, responses of canopy apparent photosynthesis (CAP), and assimilate redistribution characters (by CO stable isotope tracing) were investigated. In this study, two maize varieties DH618 and DH605 were grown at various planting densities (6.75, 8.25, 9.75, and 11.25 pl m) and N application rates (0, 180, 270, 360, and 540 kg ha) during 2013-2015. Maize grain yield (GY) was maximized at a density of 9.75 pl m with 180-360 kg ha N during the three study years. Maize GY, biomass, CAP, leaf area index (LAI), and C-photosynthate reallocation all responded more intensively to density than N rate, but the N response differed between varieties. We established links among CAP, LAI and biomass, and GY and kernel number per unit area (KNA). CAP depended on high LAI and enzyme activities for photosynthesis, yet both N deficiency and N excess had inhibitory effects. Besides, relations between C-photosynthate reallocation and yield components were executed. High density increased the C-photosynthate distribution in vegetative organs but reduced the allocation in ear, while N supply moderated the response. Based on our results, maize plants with greater CAP, more C-photosynthate distribution to ears, and less C-photosynthate distribution to stems under different density and N rate combinations could improve KNA and achieve a greater GY consequently.
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http://dx.doi.org/10.3389/fpls.2019.01113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6761910PMC
September 2019
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