Publications by authors named "Le Fu"

17 Publications

  • Page 1 of 1

Three-Dimensional Insights into Interfacial Segregation at the Atomic Scale in a Nanocrystalline Glass-Ceramic.

Nano Lett 2021 Aug 9;21(16):6898-6906. Epub 2021 Aug 9.

Department of Materials Science and Engineering, McMaster University, Hamilton, L8S 4L8 Ontario, Canada.

The distribution of dopant atoms plays a key role in the effectiveness of doping, thereby requiring delicate characterizations. In this study, we found that energy-dispersive X-ray spectroscopy (EDX) and electron energy loss spectroscopy (EELS) techniques in scanning transmission electron microscopy (STEM) were not adequate to reveal the distribution of yttrium and the chemical composition of the ZrO/SiO heterophase interface in an yttrium-doped ZrO-SiO nanocrystalline glass-ceramic. Atom probe tomography (APT) is rarely utilized to characterize ceramics due to some inherent difficulties. However, we successfully revealed the three-dimensional distribution of ZrO nanocrystallites and SiO matrix at the atomic scale with APT under optimized and well-controlled conditions. We also found that the ZrO nanocrystallites had a special core-shell structure, with a thin Zr/Si interfacial layer as a shell and a ZrO solid solution as a core. Yttrium dopants showed interfacial segregation at both ZrO grain boundaries and the ZrO/SiO heterophase interfaces.
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http://dx.doi.org/10.1021/acs.nanolett.1c02051DOI Listing
August 2021

Detection of deep myometrial invasion in endometrial cancer MR imaging based on multi-feature fusion and probabilistic support vector machine ensemble.

Comput Biol Med 2021 07 11;134:104487. Epub 2021 May 11.

School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai, China.

The depth of myometrial invasion affects the treatment and prognosis of patients with endometrial cancer (EC), conventionally evaluated using MR imaging (MRI). However, only a few computer-aided diagnosis methods have been reported for identifying deep myometrial invasion (DMI) using MRI. Moreover, these existing methods exhibit relatively unsatisfactory sensitivity and specificity. This study proposes a novel computerized method to facilitate the accurate detection of DMI on MRI. This method requires only the corpus uteri region provided by humans or computers instead of the tumor region. We also propose a geometric feature called LS to describe the irregularity of the tissue structure inside the corpus uteri triggered by EC, which has not been leveraged for the DMI prediction model in other studies. Texture features are extracted and then automatically selected by recursive feature elimination. Utilizing a feature fusion strategy of strong and weak features devised in this study, multiple probabilistic support vector machines incorporate LS and texture features, which are then merged to form the ensemble model EPSVM. The model performance is evaluated via leave-one-out cross-validation. We make the following comparisons, EPSVM versus the commonly used classifiers such as random forest, logistic regression, and naive Bayes; EPSVM versus the models using LS or texture features alone. The results show that EPSVM attains an accuracy, sensitivity, specificity, and F1 score of 93.7%, 94.7%, 93.3%, and 87.8%, all of which are higher than those of the commonly used classifiers and the models using LS or texture features alone. Compared with the methods in existing studies, EPSVM exhibits high performance in terms of both sensitivity and specificity. Moreover, LS can achieve an accuracy, sensitivity, and specificity of 89.9%, 89.5%, and 90.0%. Thus, the devised geometric feature LS is significant for DMI detection. The fusion of LS and texture features in the proposed EPSVM can provide more reliable prediction. The computer-aided classification based on the proposed method can assist radiologists in accurately identifying DMI on MRI.
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http://dx.doi.org/10.1016/j.compbiomed.2021.104487DOI Listing
July 2021

Association Between Red Cell Distribution Width and Hospital Mortality in Patients with Sepsis.

J Int Med Res 2021 Apr;49(4):3000605211004221

Department of Critical Care Medicine, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China.

Objective: Sepsis is the leading cause of death in patients admitted to adult intensive care units (ICUs). We aimed to determine the predictive value of red blood cell distribution width (RDW) in patients with sepsis in a large cohort.

Methods: This retrospective observational study used data from the eICU Collaborative Research Database. The prognostic value of RDW was investigated using the receiver operating characteristic (ROC) curve, multiple logistic regression model, integrated discriminatory index (IDI), and net reclassification index (NRI).

Results: In total, 9743 patients were included. The area under the ROC curve of the RDW for predicting hospital mortality was 0.631 (95% confidence interval [CI]: 0.616-0.645). Based on the multiple logistic regression model, an RDW of ≥14.5% was correlated with hospital mortality, regardless of Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation IV (APACHE IV) scores (odds ratio [OR]: 1.838, 95% CI: 1.598-2.119). Using SOFA and APACHE IV scores as reference, the IDI and continuous NRI of RDW for hospital mortality was about 0.3 and 0.014, respectively.

Conclusions: The RDW may be useful in predicting hospital mortality in patients with sepsis, offering extra prognostic value beyond SOFA and APACHE IV scores.
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http://dx.doi.org/10.1177/03000605211004221DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033474PMC
April 2021

Clinical Predictors for Functional Independence After Tissue-Window Guided Endovascular Thrombectomy.

World Neurosurg 2021 02 17;146:e947-e954. Epub 2020 Nov 17.

Neurology Department, The First Affiliated Hospital of Soochow University, Suzhou, China. Electronic address:

Objective: Thrombectomy increases the survival rate of acute ischemic stroke patients corresponding to large vessel occlusion. This study aimed to determine clinical predictors for good outcomes in patients subjected to tissue window guided thrombectomy.

Methods: This study was performed at the stroke center of the First Affiliated Hospital of SooChow University. Baseline characteristics and outcomes were retrospectively collected, 90 days after endovascular thrombectomy. Collection was done within 6-24 hours after a patient was last seen in good condition. Binary logistic regression was used to establish the clinical predictors for functional independence. Receiver operator characteristic curve analysis was performed to determine cutoff values for outcome predictors. P value <0.05 was considered to be statistically significant.

Results: Forty-seven patients were enrolled in this study. Among them, 13 (27.7%) had last presenting stroke, 24 (51.1%) had wake-up stroke, and 10 (21.3%) had daytime unknown stroke onset. The median initial National Institutes of Health Stroke Scale (NIHSS) score, infarct core volume, and ischemic penumbra volume were 15 (interquartile range [IQR] 11-18), 20 (IQR 8-36) mL, and 115 (IQR 81-176) mL, respectively. Multivariate regression analysis showed that patients with a lower initial NIHSS score, smaller ischemic penumbra, and no hemorrhagic transformation were more likely to have good outcomes. As shown by the receiver operator characteristic curves, the optimal thresholds of initial NIHSS score, ischemic penumbra, and infarct core were 14.5 (AUC: 0.867; P < 0.001), 109 mL (AUC: 0.841; P < 0.001), and 12.5 mL (AUC: 0.681; P = 0.036), respectively.

Conclusions: A lower initial NIHSS score, smaller ischemic penumbra, and lack of hemorrhagic transformation are significant independent predictors for good outcomes after a tissue-window based thrombectomy.
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http://dx.doi.org/10.1016/j.wneu.2020.11.047DOI Listing
February 2021

The value of microendoscopy in the diagnosis of cervical precancerous lesions and cervical microinvasive carcinoma.

Arch Gynecol Obstet 2020 08 5;302(2):455-462. Epub 2020 Jun 5.

Department of Obstetrics and Gynecology, East Hospital, Tongji University School of Medicine, Shanghai, China.

Purpose: Cervical cancer is still one of the main causes of death in females. Conventional diagnostic tools such as colposcopy are still unsatisfactory, so accurate diagnostic tools for cervical diseases are needed. Therefore, the purpose of this study was to perform a clinical study to evaluate the value of microendoscopic imaging systems in the diagnosis of cervical precancerous lesions and cervical microinvasive carcinoma (MIC).

Methods: Totally 106 patients ranging in age from 23 to 67 years were recruited. All patients had abnormal thin-layer cytology (TCT) results (≥ low-grade squamous intraepithelial lesions) and high-risk human papillomavirus (HPV) positivity. Each patient was first subjected to ordinary colposcopy, followed by microendoscopy and biopsy. All results of the colposcopy and microendoscopy images were compared to the histopathological diagnosis.

Results: Characteristics of pathological blood vessels were easily distinguished by microendoscopy compared with ordinary colposcopy. The diagnostic agreement rate of microendoscopy with the pathological diagnosis was higher (95.3%) than that of ordinary colposcopy (37.7%) (weighted kappa = 0.863, P < .01). When diagnosing HSIL and more advanced disease, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the microendoscopic diagnosis were significantly higher than those of ordinary colposcopy (97.6 and 38.1%), (95.5 and 63.6%), (98.8 and 80.0%), (91.3 and 21.2%) and (97.7 and 43.4%), respectively.

Conclusion: This study shows that microendoscopy has important value in the diagnosis of cervical lesions which can provide real-time diagnosis in vivo without staining, particularly for lesions that are not sensitive to acetic acid staining.
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http://dx.doi.org/10.1007/s00404-020-05565-8DOI Listing
August 2020

Enhancement of osteoblast cells osteogenic differentiation and bone regeneration by hydroxyapatite/phosphoester modified poly(amino acid).

Mater Sci Eng C Mater Biol Appl 2020 Jun 22;111:110769. Epub 2020 Feb 22.

College of Physics, Sichuan University, Chengdu, Sichuan 610065, China. Electronic address:

Hydroxyapatite/poly(amino acid) (HA/PAA) has been used to treat a variety of long bone and vertebral bony defects, and a further biocompatibility improvement is a key for better application. Phosphoester (PE) contained materials are highly biocompatible but could hardly treat massive bone defects due to its fast-degradation-derived mechanical instability. To address the problems of the two materials, we have incorporated PE molecule into the main chain of PAA by chemical bonding. As a result, the compressive strength of HA/PAA with 1 wt% and 2.5 wt% PE maintained in the range of 80-150 MPa after soaking in PBS for 12 weeks, which could be attributed to the amplified hydrogen-bonding inside composites. Besides, the PE-containing HA/PAAs with increased hydrophilic function groups (O=P-O bonds and O=P-N), created a more favourable surface for cell adhesion. Meanwhile, compared with HA/PAA, the PE-containing HA/PAAs had a fast minerlization speed and promoted cell osteogenic differentiation. Furthermore, the in vivo study indicated that PE-containing HA/PAAs could facilitate bone formation (4 weeks), and form a complete bone bridging (12 weeks) in a rabbit cranial bone defect. In summary, the HA/PE-m-PAAs possessed good mechanical stability, improved cytocompatibility and osteoconductivity, so the composites have a great potential for massive bone defect treatment.
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http://dx.doi.org/10.1016/j.msec.2020.110769DOI Listing
June 2020

Glass-Ceramics in Dentistry: A Review.

Materials (Basel) 2020 Feb 26;13(5). Epub 2020 Feb 26.

Applied Materials Science, Department of Engineering Science, Uppsala University, 751 21 Uppsala, Sweden.

In this review, we first briefly introduce the general knowledge of glass-ceramics, including the discovery and development, the application, the microstructure, and the manufacturing of glass-ceramics. Second, the review presents a detailed description of glass-ceramics in dentistry. In this part, the history, property requirements, and manufacturing techniques of dental glass-ceramics are reviewed. The review provided a brief description of the most prevalent clinically used examples of dental glass-ceramics, namely, mica, leucite, and lithium disilicate glass-ceramics. In addition, we also introduce the newly developed ZrO-SiO nanocrystalline glass-ceramics that show great potential as a new generation of dental glass-ceramics. Traditional strengthening mechanisms of glass-ceramics, including interlocking, ZrO-reinforced, and thermal residual stress effects, are discussed. Finally, a perspective and outlook for future directions in developing new dental glass-ceramics is provided to offer inspiration to the dental materials community.
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http://dx.doi.org/10.3390/ma13051049DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7084775PMC
February 2020

Elemental Mercury Removal by a Method of Ultraviolet-Heat Synergistically Catalysis of HO-Halide Complex.

Environ Sci Technol 2019 Jul 5;53(14):8324-8332. Epub 2019 Jul 5.

Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science and Engineering , North China Electric Power University , Baoding , 071003 , PR China.

A novel method of ultraviolet-heat synergistically catalyzing HO-X (X: NaCl, NaBr, HCl, and HBr) for removal of elemental mercury (Hg) was developed. In terms of Hg removal efficiency and economy, HCl and HBr were the suitable additives. Hg removal efficiencies reached 93.6% for HO-HCl and 91.4% for HO-HBr, the concentrations of HO, HCl and HBr were 1 M, 4.2 mM and 0.5 mM. The doses of gaseous Cl and Br-oxidants were 6.27 and 0.75 ppm. The costs by using HO-HCl and HO-HBr were 1,180 USD/lb-Hg and 1,170 USD/lb-Hg. The best temperature for heat catalysis was 413 K. Hg removal was enhanced by 500 mg/m SO and 300 mg/m NO due to the formation of sulfuric and NO. Mercury distribution analyses indicated that 500 mg/m SO, 300 mg/m NO, and 6% O favored KCl retaining Hg. When the HO concentration was adjusted to 3 M, the simultaneous removal efficiencies of NO and Hg reached 83.7% and 99.2% for HO-HCl, and 82.8% and 98.8% for HO-HBr. Electron spin resonance demonstrated that ClOH•/BrOH• and Cl•/Br• played leading roles in Hg oxidation, besides Cl/Br. The mercury forms in spent KCl were HgCl, HgBr, and HgNO, according to X-ray photoelectron spectroscopy.
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http://dx.doi.org/10.1021/acs.est.9b01741DOI Listing
July 2019

The effects of parafoveal word frequency and segmentation on saccade targeting during Chinese reading.

Psychon Bull Rev 2019 Aug;26(4):1367-1376

Department of Psychology, Macquarie University, Balaclava Road, North Ryde, NSW 2019, Sydney, Australia.

Two eye-movement experiments are reported in which a boundary paradigm was used to manipulate the presence versus absence of boundaries for high-frequency and low-frequency target words in the parafovea. In Experiment 1, this was done by introducing a blank space after the target words, whereas in Experiment 2 this was done by rendering the target words in red. In both experiments, higher frequency targets engendered longer saccades, whereas the presence of parafoveal word boundaries engendered shorter saccades. This pattern suggests the operation of two countermanding saccade-targeting mechanisms: one that uses parafoveal processing difficulty to adjust saccade lengths and a second that uses word boundaries to direct the eyes toward specific saccade targets. The implications of these findings for models of eye-movement control during reading are discussed, as are suggestions for integrating dynamic-adjustment and default-targeting accounts.
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http://dx.doi.org/10.3758/s13423-019-01577-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6711815PMC
August 2019

Incorporation of strontium and europium in crystals of α-calcium isosaccharinate.

J Hazard Mater 2019 02 2;364:309-316. Epub 2018 Oct 2.

Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm, Sweden. Electronic address:

The final repository for short-lived, low and intermediate level radioactive waste in Sweden is built to act as a passive repository. Already within a few years after closure water will penetrate the repository and conditions of high alkalinity (pH 10.5-13.5) and low temperature (< 7 °C) will prevail. The mobility of radionuclides in the repository is dependent on the radionuclides distribution between solid and liquid phases. In the present work the incorporation of strontium (II) and europium (III) in α-calcium isosaccharinate (ISA) under alkaline conditions (pH ∼10) at 5 °C and 50 °C have been studied. The results show that strontium and europium are incorporated into α-Ca(ISA) when crystallized both at 5 °C and 50 °C. Europium is incorporated to a greater extent than strontium. The highest incorporation of europium and strontium at 5 °C rendered the phase compositions CaEu(ISA) (2.4% of Eu(ISA) by mass) and CaSr(ISA) (2.2% of Sr(ISA) by mass). XPS spectra show that both trivalent and divalent Eu coexist in the Eu incorporated samples. Strontium ions were found to retard the elongated growth of the Ca(ISA) crystals. The incorporation of Sr and Eu into the solid phase of Ca(ISA) is expected to contribute to a decreased mobility of these ions in the repository.
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http://dx.doi.org/10.1016/j.jhazmat.2018.10.001DOI Listing
February 2019

Ultrastrong Translucent Glass Ceramic with Nanocrystalline, Biomimetic Structure.

Nano Lett 2018 11 23;18(11):7146-7154. Epub 2018 Oct 23.

Applied Materials Science, Department of Engineering Science , Uppsala University , Uppsala 751 21 , Sweden.

Transparent/translucent glass ceramics (GCs) have broad applications in biomedicine, armor, energy, and constructions. However, GCs with improved optical properties typically suffer from impaired mechanical properties, compared to traditional sintered full-ceramics. We present a method of obtaining high-strength, translucent GCs by preparing ZrO-SiO nanocrystalline glass ceramics (NCGCs) with a microstructure of monocrystalline ZrO nanoparticles (NPs), embedded in an amorphous SiO matrix. The ZrO-SiO NCGC with a composition of 65%ZrO/35%SiO (molar ratio, 65Zr) achieved an average flexural strength of 1 GPa. This is one of the highest flexural strength values ever reported for GCs. ZrO NPs bond strongly with SiO matrix due to the formation of a thin (2-3 nm) amorphous Zr/Si interfacial layer between the ZrO NPs and SiO matrix. The diffusion of Si atoms into the ZrO NPs forms a Zr-O-Si superlattice. Electron tomography results show that some of the ZrO NPs are connected in one direction, forming in situ ZrO nanofibers (with length of ∼500 nm), and that the ZrO nanofibers are stacked in an ordered way in all three dimensions. The nanoarchitecture of the ZrO nanofibers mimics the architecture of mineralized collagen fibril in cortical bone. Strong interface bonding enables efficient load transfer from the SiO matrix to the 3D nanoarchitecture built by ZrO nanofibers and NPs, and the 3D nanoarchitecture carries the majority of the external load. These two factors synergistically contribute to the high strength of the 65Zr NCGC. This study deepens our fundamental understanding of the microstructure-mechanical strength relationship, which could guide the design and manufacture of other high-strength, translucent GCs.
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http://dx.doi.org/10.1021/acs.nanolett.8b03220DOI Listing
November 2018

Decreased apparent diffusion coefficient in the placentas of monochorionic twins with selective intrauterine growth restriction.

Placenta 2018 09 5;69:26-31. Epub 2018 Jul 5.

Department of Radiology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, PR China. Electronic address:

Objectives: The apparent diffusion coefficient (ADC) was associated with the onset of intrauterine growth restriction in singleton pregnancies. However, the correlation of ADC with selective intrauterine growth restriction (sIUGR) of monochorionic (MC) twin pregnancies remained unknown. In this study, we aimed to evaluate the association of ADC with sIUGR in MC twin pregnancies by exploring diffusion weighted MR imaging (DWI).

Methods: Fifty-one MC twin pregnancies, consisting 19 cases of sIUGR and 32 cases without sIUGR, were re-analyzed by DWI. ADCs were quantitated from two regions of interest, surrounding the insertion of the umbilical cord of placenta for each twin. A rADC (ADC/ADC) in each placenta was also evaluated. Then ADCs and rADCs were compared between cases with and without sIUGR.

Results: The ADC in cases with sIUGR was significantly decreased compared with cases without sIUGR (1.846 × 10 vs 2.471 × 10 mm/s, p < 0.001). The rADC in cases with sIUGR was significantly increased (1.346 vs 1.053, p < 0.001).

Conclusions: The ADC decreases and the rADC increases in the placentas of MC twins with sIUGR, suggesting that diffusion in the placenta is restricted in pregnancies with sIUGR.
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http://dx.doi.org/10.1016/j.placenta.2018.07.001DOI Listing
September 2018

Biological floating bed and bio-contact oxidation processes for landscape water treatment: simultaneous removal of Microcystis aeruginosa, TOC, nitrogen and phosphorus.

Environ Sci Pollut Res Int 2018 Aug 13;25(24):24220-24229. Epub 2018 Jun 13.

School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.

The aim of this study was to identify algicidal bacteria J25 against the Microcystis aeruginosa (90.14%), Chlorella (78.75%), Scenedesmus (not inhibited), and Oscillatoria (90.12%). Meanwhile, we evaluate the SOD activity and efficiency of denitrification characteristics with Acinetobacter sp. J25. A novel hybrid bioreactor combined biological floating bed with bio-contact oxidation (BFBO) was designed for treating the landscape water, and the average removal efficiencies of nitrate-N, ammonia-N, nitrite-N, TN, TP, TOC, and algal cells were 91.14, 50, 87.86, 88.83, 33.07, 53.95, and 53.43%, respectively. A 454-pyrosequencing technology was employed to investigate the microbial communities of the BFBO reactor samples. The results showed that Acinetobacter sp. J25 was the dominant contributor for effective removal of N, algal cells, and TOC in the BFBO reactor. And the relative abundance of Acinetobacter showed increase trend with the delay of reaction time. Graphical abstract Biological floating bed and bio-contact oxidation (BFBO) as a novel hybrid bioreactor designed for simultaneous removal Microcystis aeruginosa, TOC, nitrogen, and phosphorus. And high-throughput sequencing data demonstrated that Acinetobacter sp. J25 was the dominate species in the reactor and played key roles in the removal of N, TOC, and M. aeruginosa. Proposed reaction mechanism of the BFBO.
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http://dx.doi.org/10.1007/s11356-018-2417-0DOI Listing
August 2018

Inhibition of AMP-activated protein kinase alleviates focal cerebral ischemia injury in mice: Interference with mTOR and autophagy.

Brain Res 2016 11 26;1650:103-111. Epub 2016 Aug 26.

Emergency Department, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.

Ischemic stroke is one of the most frequent acute cerebrovascular events worldwide. This study evaluated the variability of AMPK and mTOR and their relevance on LC3 and Beclin-1 expression, and further expounded the possible protective mechanism of inhibiting AMPK activity in the cerebral cortex after permanent focal cerebral ischemia injury in mice. Western blot and immunohistochemistry showed that p-AMPK expression was low in the cerebral cortex of the sham group; whereas it was significantly increased at 3h and 6h and peaked at 3h after pMCAO in the cerebral ischemic cortex, and was decreased at 12h and 24h. The expression patterns of LC3 and Beclin-1 were the same as that of p-AMPK after occlusion, and the variability pattern between p-AMPK and p-mTOR levels was completely inverted. After treatment with the AMPK inhibitor Compound C, p-AMPK/LC3/Beclin-1 expression was decreased significantly, whereas p-mTOR level was increased significantly. Deficiency of Nissl bodies was reduced compared with that in the vehicle group at all times points after occlusion. Neurological deficits, infarct areas, and brain water content were also significantly reduced 24h after occlusion with compound C treatment. The results suggested that the AMPK-autophagy pathway was activated, concomitant with mTOR inhibition in cerebral cortex after ischemic injury in mice. Moreover, inhibition of AMPK activity by Compound C inhibited autophagy and conferred protection against brain damage by restoring mTOR activity.
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http://dx.doi.org/10.1016/j.brainres.2016.08.035DOI Listing
November 2016

[Dynamic changes of ROS, MDA and SOD during arsenic-induced neoplastic transformation in human keratinocytes].

Wei Sheng Yan Jiu 2015 May;44(3):456-61

Objective: To investigate the level of ROS, MDA and SOD in different stages of arsenic-induced neoplastic transformation in human keratinocytes.

Methods: HaCaT human immortalized keratinocytes were continuously exposed to 1.0 μmol/L arsenite for 35 passages. The secretion of active MMP-9, the proliferation rate and doubling time nd colony formation assay in soft agar colony were used to identify the malignant phenotype of the arsenite-exposed HaCaT cells. Then flow cytometry was used to detect the levels of ROS, and the level of MDA and SOD were tested by biochemical method at different passages of arsenite exposure in HaCaT cells.

Results: A marked increase in the secretion of active MMP-9 in the arsenic-treated (1.0 μmol/L NaAsO2) cells was observed in comparison to the passage-matched untreated control (0.0 μmol/L NaAsO2) cells at 28 and 35 passages. And compared with 0.0 μmol/L NaAsO2 group, the proliferation rate and doubling time in 1.0 μmol/L NaAsO2 group was much faster at 21 ((64.37 ± 15.92) h) and 28 ((64.04 ± 12.84) h) passages with a significant statistical difference at passage 35 ((54.00 ± 2.35 ) h) (P < 0.05). Furthermore, the long-term arsenite-treated cells formed significantly higher colonies (107 ± 11 in passage 35) in soft agar than control cells (P < 0.05). No obvious regularity changes of ROS and MDA levels were found before 14 passages of arsenite exposure, except for passage 1. Surprisingly, after 14 passages, with the increased passages of exposure to arsenite, both the ROS and MDA levels decreased gradually, the ROS level at passage 35 was significant lower compared to passage 0 (P < 0.05). Conversely, after passage 21, the activity of SOD was obviously enhanced and reached the highest level at passage 35.

Conclusion: Long-term exposure to low concentrations of inorganic arsenic-induced malignant transformation of HaCaT cells is accompanied by intracellular imbalance between oxidative-antioxidant, which increased expression of SOD and low levels of ROS found in the later-stage of arsenite-induced transformation.
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May 2015

Shedding of c-Met ectodomain correlates with c-Met expression in non-small cell lung cancer.

Biomarkers 2013 Mar;18(2):126-35

Department of Radiology, Huashan Hospital of Fudan University, Shanghai, China.

Objective: The aim of this study is to reveal the correlation of shedding and expression of c-Met in non-small cell lung cancer (NSCLC) patient.

Materials And Methods: We measured soluble c-Met and c-Met level in a panel of pre-clinical models and 197 advanced Chinese NSCLC patients by enzyme-linked immunosorbent assay and immunohistochemistry, respectively.

Results: Shedding of soluble c-Met associates with total c-Met amount in pre-clinical models, and soluble c-Met correlates with both c-Met expression level and tumor size in human, high soluble c-Met predicts poorer outcome.
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http://dx.doi.org/10.3109/1354750X.2012.751455DOI Listing
March 2013

Unglycosylation at Asn-633 made extracellular domain of E-cadherin folded incorrectly and arrested in endoplasmic reticulum, then sequentially degraded by ERAD.

Glycoconj J 2008 Nov 20;25(8):727-40. Epub 2008 May 20.

Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, 138 Yi Xue Yuan Road, Shanghai, 200032, People's Republic of China.

The human E-cadherin is a single transmembrane domain protein involved in Ca(2+)-dependent cell-cell adhesion. In a previous study, we demonstrated that all of four potential N-glycosylation sites in E-cadherin are occupied by N-glycans in human breast carcinoma cells in vivo and the elimination of N-glycan at Asn-633 dramatically affected E-cadherin expression and made it degraded. In this study we investigated the molecular mechanism of E-cadherin, which lacks N-glycosylation at Asn-633 (M4), degradation and the role of the N-glycan at Asn-633 in E-cadherin folding. We treated cells stably expressed M4 E-cadherin with MG123, DMM, respectively. Either MG132 or DMM could efficiently block degradation of M4 E-cadherin. M4 E-cadherin was recognized as the substrate of ERAD and was retro-translocated from ER lumen to cytoplasm by p97. It was observed that the ration of M4 E-cadherin binding to calnexin was significantly increased compared with that of other variants, suggesting that it was a misfolded protein, though cytoplasmic domain of M4 E-cadherin could associate with beta-catenin. Furthermore, we found that N-glycans of M4 E-cadherin were modified in immature high mannose type, suggesting that it could not depart to Golgi apparatus. In conclusion, this study revealed that N-glycosylation at Asn-633 is essential for E-cadherin expression, folding and trafficking.
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http://dx.doi.org/10.1007/s10719-008-9133-9DOI Listing
November 2008
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