Publications by authors named "Xuehan Li"

22 Publications

  • Page 1 of 1

Construction of a Super-Folder Fluorescent Protein-Guided Secretory Expression System for the Production of Phospholipase D in .

J Agric Food Chem 2021 Jun 14. Epub 2021 Jun 14.

College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China.

Phospholipids (PLs) are one of the main ingredients in food and nutraceutical, cosmetics, agriculture, and pharmaceutical products. Phospholipase D (PLD) is a crucial enzyme for the biocatalytic synthesis or modification of PLs. Here, to prepare PLD more efficiently, we constructed a PLD expression and secretion system in and developed an environmentally friendly reaction system. A nonclassical secretory pathway where a super-folder green fluorescent protein plays as an N-terminal guide protein was introduced. This expression system can not only achieve rapid screening of high-level expression strains but can also achieve the secretion of the target proteins. Under optimal fermentation conditions, the enzyme activity of the culture medium was 0.35 U/mL, which was 2.05-fold that of the Sec secretion pathway strains. Meanwhile, the effects of several organic solvents in the biphasic reaction media were compared. The results showed that when using cyclopentyl methyl ether as the organic phase, the final conversion rate reached 96.9%. It has shown good application potential in the synthesis of phosphatidylserine, laid the foundation for the synthesis and application of other rare and high-value PLs, and provided a reference for the production of other biocatalysts.
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http://dx.doi.org/10.1021/acs.jafc.1c02089DOI Listing
June 2021

Effect of Root Canal Therapy on the Success Rate of Teeth with Complete Roots in Autogenous Tooth Transplantation.

Scanning 2021 14;2021:6675604. Epub 2021 Apr 14.

Department of Oral and Maxillofacial Surgery, Graduate School of Clinical Dentistry, Korea University, Seoul 02841, Republic of Korea.

Background: Autogenous tooth transplantation is a reliable method for repairing missing teeth. Although it recently became a recognized and feasible treatment method in dentistry, the long-term efficacy of root canal therapy (RCT) has not been well confirmed. This study is aimed at determining whether RCT has a good effect on the success rate of teeth with complete roots in autogenous tooth transplantation.

Materials And Methods: Data were collected from the Korea University Guro Hospital. Data of patients who underwent autogenous tooth transplantation within 9 years were collected. We selected 29 teeth with complete roots as the research subjects in our study. None of the patients had any systemic diseases. All cases in this study were obtained with patient permission.

Results: According to the tooth vitality test, the autogenous teeth tested negative in dental pulp test and function. Nine of the 29 teeth with autogenous tooth transplantation were treated with RCT and survived throughout the observation period. However, 20 autogenous teeth were not treated with RCT, and eight of them did not survive. All statistical analyses were performed using IBM SPSS 20.0. The null hypothesis was rejected ( < 0.05).

Conclusion: For complete root teeth, the success rate after autogenous tooth transplantation after RCT is higher than that of teeth not treated with RCT.
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http://dx.doi.org/10.1155/2021/6675604DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062180PMC
April 2021

Comparison of Autogenous Tooth Materials and Other Bone Grafts.

Tissue Eng Regen Med 2021 Jun 30;18(3):327-341. Epub 2021 Apr 30.

Department of Oral and Maxillofacial Surgery, Graduate School of Clinical Dentistry, Korea University, Seoul, 02841, Republic of Korea.

Autogenous odontogenic materials are a new, highly biocompatible option for jaw restoration. The inorganic component of autogenous teeth acts as a scaffold to maintain the volume and enable donor cell attachment and proliferation; the organic component contains various growth factors that promote bone reconstruction and repair. The composition of dentin is similar to that of bone, which can be a rationale for promoting bone reconstruction. Recent advances have been made in the field of autogenous odontogenic materials, and studies have confirmed their safety and feasibility after successful clinical application. Autogenous odontogenic materials have unique characteristics compared with other bone-repair materials, such as the conventional autogenous, allogeneic, xenogeneic, and alloplastic bone substitutes. To encourage further research into odontogenic bone grafts, we compared the composition, osteogenesis, and development of autogenous odontogenic materials with those of other bone grafts. In conclusion, odontogenic bone grafts should be classified as a novel bone substitute.
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http://dx.doi.org/10.1007/s13770-021-00333-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169722PMC
June 2021

Positive End-Expiratory Pressure, Pleural Pressure, and Regional Compliance during Pronation: An Experimental Study.

Am J Respir Crit Care Med 2021 05;203(10):1266-1274

Interdepartmental Division of Critical Care Medicine.

The physiological basis of lung protection and the impact of positive end-expiratory pressure (PEEP) during pronation in acute respiratory distress syndrome are not fully elucidated. To compare pleural pressure (Ppl) gradient, ventilation distribution, and regional compliance between dependent and nondependent lungs, and investigate the effect of PEEP during supination and pronation. We used a two-hit model of lung injury (saline lavage and high-volume ventilation) in 14 mechanically ventilated pigs and studied supine and prone positions. Global and regional lung mechanics including Ppl and distribution of ventilation (electrical impedance tomography) were analyzed across PEEP steps from 20 to 3 cm HO. Two pigs underwent computed tomography scans: tidal recruitment and hyperinflation were calculated. Pronation improved oxygenation, increased Ppl, thus decreasing transpulmonary pressure for any PEEP, and reduced the dorsal-ventral pleural pressure gradient at PEEP < 10 cm HO. The distribution of ventilation was homogenized between dependent and nondependent while prone and was less dependent on the PEEP level than while supine. The highest regional compliance was achieved at different PEEP levels in dependent and nondependent regions in supine position (15 and 8 cm HO), but for similar values in prone position (13 and 12 cm HO). Tidal recruitment was more evenly distributed (dependent and nondependent), hyperinflation lower, and lungs cephalocaudally longer in the prone position. In this lung injury model, pronation reduces the vertical pleural pressure gradient and homogenizes regional ventilation and compliance between the dependent and nondependent regions. Homogenization is much less dependent on the PEEP level in prone than in supine positon.
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http://dx.doi.org/10.1164/rccm.202007-2957OCDOI Listing
May 2021

Inhibition of ACSL4 attenuates ferroptotic damage after pulmonary ischemia-reperfusion.

FASEB J 2020 12 18;34(12):16262-16275. Epub 2020 Oct 18.

Department of Anesthesiology, West China Hospital, Sichuan University, The Research Units of West China (2018RU12), Chinese Academy of Medical Sciences, Chengdu, China.

Lung ischemia-reperfusion (IR) injury is a common clinical pathology associated with high mortality. Ferroptosis, a novel mode of cell death elicited by iron-dependent phospholipid peroxidation, has been implicated in ischemic events. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is one of the main enzymes in pro-ferroptotic lipid metabolism. In this study, the involvement of ferroptotic death in different durations of reperfusion was evaluated by assessing the iron content, malondialdehyde, and glutathione levels, ferroptosis-related protein expression, and mitochondria morphology. The roles of ferroptosis-specific inhibitor, liproxastin-1 (Lip-1), and ACSL4 modulation in a preventive regimen were assessed in vivo and in vitro. The hallmarks of pulmonary function, such as histological lung injury score, wet/dry ratio, and oxygenation index, were evaluated as well. Results showed that lung IR increased the tissue iron content and lipid peroxidation accumulation, along with key protein (GPX4 and ACSL4) expression alteration during reperfusion. Pretreatment with Lip-1 inhibited ferroptosis and ameliorated lung IR-induced injury in animal and cell models. In addition, administering ACSL4 inhibitor rosiglitazone before ischemia diminished the ferroptotic damage in IR-injured lung tissue, consistent with the protective effect of ACSL4 knockdown on lung epithelial cells subjected to hypoxia/reoxygenation. Thus, this study delineated that IR-induced ferroptotic cell death in lung tissue and ACSL4 were correlated with this process. Inhibition of ferroptosis and ACSL4 mitigated the ferroptotic damage in IR-induced lung injury by reducing lipid peroxidation and increasing the glutathione and GPX4 levels.
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http://dx.doi.org/10.1096/fj.202001758RDOI Listing
December 2020

Molecular Characteristics, Virulence Gene and Wall Teichoic Acid Glycosyltransferase Profiles of : A Multicenter Study in China.

Front Microbiol 2020 19;11:2013. Epub 2020 Aug 19.

Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.

() constantly evolves under host and environment pressures. The monitoring network is essential in assessing the epidemiology of infections. A total of 555 isolates were collected from five hospitals in three different geographical regions of China for the investigation of molecular characteristics, antibiotic resistance, virulence gene, and wall teichoic acid (WTA) glycosyltransferase gene profiles. 233 (42.0%) isolates were identified as MRSA, and 323 (58.2%) were defined as multidrug-resistant (MDR) isolates. MRSA prevalence showed no significant difference among the three regions. In contrast, the MDR prevalence was significantly higher in central China than that in northern China (63.5% vs. 50.8%, < 0.05). Thirty-eight sequence types (STs) belonging to 17 clone complexes (CCs) and 126 distinct -types were identified. The most prevalent clone was ST59-t437 (9.7%, 54/555), followed by ST22-t309 (7.6%, 42/555) and ST5-t2460 (7.2%, 40/555). Most ST59-t437 and ST5-t2460 were MRSA isolates, whereas most ST22-t309 was MSSA isolates. The predominant clones varied in different geographical areas. The distribution of the , , , , , , , , and genes showed significant differences among different regions. We found five WTA glycosyltransferase gene profiles, with -/+/-/- being the most common combination. Remarkably, the gene was identified in more CCs than just CC5 and CC398. All of 16 -positive isolates also contained the . Moreover, was present in almost all isolates except 10 ST630 isolates. The gene was only detected in 10 of 12 ST630 isolates without . The gene was absent in CC5 and CC398. In brief, there were regional differences among molecular characteristics, antibiotic resistance, and virulence gene profiles. The -negative ST630 lineage carried the , which was never found before, indicating that it may be capable of expressing GroP-α-GalNAc WTA and exchanging mobile genetic elements with coagulase-negative staphylococci (CoNS).
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http://dx.doi.org/10.3389/fmicb.2020.02013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466653PMC
August 2020

Molecular Characteristics, Antimicrobial Resistance and Virulence Gene Profiles of Isolates from Wuhan, Central China.

Infect Drug Resist 2020 30;13:2063-2072. Epub 2020 Jun 30.

Department of Clinical Laboratory, Zhongnan Hospital, Wuhan University, Wuhan, People's Republic of China.

Purpose: This study aimed to investigate the molecular characteristics, antimicrobial resistance and virulence genes profiles of isolates from Wuhan, central China.

Materials And Methods: A total of 302 non-duplicate isolates were collected successively during January-December 2018 and subjected to multi-locus sequence typing (MLST), () typing and (PVL) and A, B, C, D, E, G, H and I ( and ) detection. All methicillin-resistant (MRSA) isolates were additionally subjected to staphylococcal chromosomal cassette (SCC) typing.

Results: Of the 302 isolates, 131 were categorised as MRSA, yielding a rate 1.4 times the average rate in China during 2018 (43.4% vs 30.9%). Thirty-one sequence types (STs) and 82 types were identified. The most prevalent clones were ST5-t2460 (10.9%), ST239-t030 (9.3%), ST188-t189 (7.9%) and ST59-t437 (6.3%). Notably, the continued prevalence of ST239-t030 in Wuhan differs from other areas in China. SCC types and subtypes I, II, III, IVa and V were present in 0.8%, 36.6%, 26.0%, 20.6% and 8.4% of MRSA isolates. A comprehensive analysis identified ST5-t2460-SCC II (25.2%,), ST239-t030-SCC III (19.8%) and ST59-t437-SCC IVa (7.6%) as the major clones among MRSA isolates. The genes and were detected at respective frequencies of 11.9%, 42.1%, 49.7%, 45.0%, 20.9%, 33.8%, 60.5%, 25.8% and 66.9%.

Conclusion: ST239-t030 remains one of the most prevalent clones in isolates from Wuhan, leading us to conclude that isolates from Wuhan possess unique molecular characteristics. The isolates also exhibit unique antimicrobial resistance profiles and harbour relatively high numbers of enterotoxin virulence genes, compared with other reports from China.
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http://dx.doi.org/10.2147/IDR.S249988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7335743PMC
June 2020

Coffee grounds derived N enriched microporous activated carbons: Efficient adsorbent for post-combustion CO capture and conversion.

J Colloid Interface Sci 2020 Oct 3;578:491-499. Epub 2020 Jun 3.

School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, PR China.

N enriched microporous active carbons (CACs) were successfully obtained with coffee grounds as precursor and KOH as activator, which were used for the capture and conversion of CO from post-combustion. The influence of preparation parameters, such as the temperature of activation and KOH/carbon ratio on textural properties of CACs were studied. N adsorption-desorption, XRD, Raman, SEM and XPS were used for characterization of the CACs. The adsorption capacities of CO CACs-2-800 are 6.22 mmol·g (1 bar) and 2.37 mmol·g (0.15 bar) at 273 K. CACs-2-800 also have high selectivity of CO/N (S = 33) and good adsorption-desorption recycle stability. Furthermore, the CACs-2-800 showed high catalytic activity for the cycloaddition of CO to epichlorohydrin. The good CO adsorption capacity, selectivity and catalytic performance indicated that CACs-2-800 could be used for the capture and conversion of CO from post-combustion.
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http://dx.doi.org/10.1016/j.jcis.2020.05.125DOI Listing
October 2020

Knockdown of ADAMDEC1 inhibits the progression of glioma in vitro.

Histol Histopathol 2020 Sep 6;35(9):997-1005. Epub 2020 May 6.

Department of Neurosurgery, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China.

Background: Glioma is one of the most lethal malignant tumors all over the world. The prognosis of patients with high‑grade glioma remains very poor. Therefore, it is urgent to find a novel strategy for the treatment of glioma. It has been reported that ADAMDEC1 could regulate the progression of multiple diseases, including cancers. However, the role of ADAMDEC1 during the tumorigenesis of glioma remains largely unknown. Methods, Gene expression of ADAMDEC1 in glioma tissues or in cells was detected by qRT-PCR. Western blot was performed to measure the protein expressions of p53, active caspase3, active caspase9, CDK2 and Cyclin A in glioma cells. Cell proliferation was detected by CCK-8 assay. Cell apoptosis or cycle was tested by flow cytometry. Transwell was used to test the invasion of glioma cells.

Results: The expression of ADAMDEC1 in glioma tissues or cells was significantly upregulated. In addition, downregulation of ADAMDEC1 notably inhibited the proliferation and induced apoptosis of glioma cells through upregulation of active caspase 3 and active caspase 9. Besides, silencing of ADAMDEC1 obviously induced G1 arrest in glioma cells via modulation of cell cycle-related proteins. Finally, knockdown of ADAMDEC1 significantly inhibited the migration and invasion of glioma cells. In contrast, overexpression of ADAMDEC1 promoted cell proliferation, migration and invasion of glioma cells.

Conclusion: Downregulation of ADAMDEC1 could significantly inhibit the tumorigenesis of glioma in vitro, which may serve as a novel target for the treatment of glioma.
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http://dx.doi.org/10.14670/HH-18-227DOI Listing
September 2020

Activation of cannabinoid receptor type 2 reduces lung ischemia reperfusion injury through PI3K/Akt pathway.

Int J Clin Exp Pathol 2019 1;12(11):4096-4105. Epub 2019 Nov 1.

Department of Anesthesiology, Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University Chengdu, Sichuan, China.

Cannabinoid receptor-2 activation plays a protective role against ischemic reperfusion injury (IRI) in various organs, and exerts a protective effect against paraquat-induced acute lung injury, while the role of CB in lung IRI remains unclear. Hence, the present study was designed to explore the role of CB in lung IRI, and whether the PI3K pathway was involved. C57BL/6 mice were subjected to lung ischemia by clamping the left hilum for 1 hour, followed by 2 hours' reperfusion. Mice were pretreated with vehicle, CB agonist JWH133, or antagonist AM630 followed by JWH133. Arterial blood and left lung tissues were collected to detect the PaO/FiO ratio, lung wet-to-dry weight ratio, lung pathologic scoring, pro-inflammatory cytokines, MDA, and SOD. Secondly, mice were pretreated with vehicle, JWH133, or both PI3K-inhibitor LY294002 and JWH133. Arterial blood and left lung tissues were collected for the above studies and protein expression of CB receptor, p-AKT, and AKT. After mice were pretreated with JWH133, IR-induced lung edema and lung histopathologic changes were significantly attenuated. Pretreatment with JWH133 improved PaO/FiO ratio, decreased lung TNF-α, IL-6, MDA levels and MPO activities, and increased SOD activity. By contrast, the protective effect of JWH133 was blocked by pretreatment with CB antagonist AM630. Similarly, pretreatment with PI3K-inhibitor weakened the protection induced by JWH133, and downregulated the expression of p-AKT without altering CB expression. The study suggested that activation of CB receptor plays a protective role against IR-induced lung injury through reducing inflammation in mice. The PI3K/Akt pathway might be involved in the protective effect of CB receptors in lung IRI.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6949786PMC
November 2019

Molecular characteristics and virulence gene profiles of Staphylococcus aureus isolates in Hainan, China.

BMC Infect Dis 2019 Oct 22;19(1):873. Epub 2019 Oct 22.

Department of Laboratory Medicine, Zhongnan Hospital, Wuhan University, 169 Donghu Road, Wuhan, 430071, People's Republic of China.

Background: There have been no reports regarding the molecular characteristics, virulence features, and antibiotic resistance profiles of Staphylococcus aureus (S. aureus) from Hainan, the southernmost province of China.

Methods: Two hundred twenty-seven S. aureus isolates, consisting of 76 methicillin-resistant S. aureus (MRSA) and 151 methicillin-susceptible S. aureus (MSSA), were collected in 2013-2014 and 2018-2019 in Hainan, and investigated for their molecular characteristics, virulence genes, antibiotic resistance profiles and main antibiotic resistance genes.

Results: Forty sequence types (STs) including three new STs (ST5489, ST5492 and ST5493), and 79 Staphylococcal protein A (spa) types were identified based on multilocus sequence typing (MLST) and spa typing, respectively. ST398 (14.1%, 32/227) was found to be the most prevalent, and the prevalence of ST398-MSSA increased significantly from 2013 to 2014 (5.5%, 5/91) to 2018-2019 (18.4%, 25/136). Seventy-six MRSA isolates were subject to staphylococcus chromosomal cassette mec (SCCmec) typing. SCCmec-IVa was the predominant SCCmec type, and specifically, ST45-SCCmec IVa, an infrequent type in mainland China, was predominant in S. aureus from Hainan. The antibiotic resistance profiles and antibiotic resistance genes of S. aureus show distinctive features in Hainan. The resistant rates of the MRSA isolates to a variety of antibiotics were significantly higher than those of the MSSA isolates. The predominant erythromycin and tetracycline resistance genes were ermC (90.1%, 100/111) and tetK (91.8%, 78/85), respectively. Eleven virulence genes, including the Panton-Valentine leukocidin (pvl) and eta, were determined, and the frequency of eta and pvl were found to be 57.3 and 47.6%. Such high prevalence has never been seen in mainland China before.

Conclusion: S. aureus isolates in Hainan have unique molecular characteristics, virulence gene and antibiotic resistance profiles, and main antibiotic resistance genes which may be associated with the special geographical location of Hainan and local trends in antibiotic use.
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http://dx.doi.org/10.1186/s12879-019-4547-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6805582PMC
October 2019

Transcriptomic analysis of interstock-induced dwarfism in Sweet Persimmon ( Thunb.).

Hortic Res 2019 1;6:51. Epub 2019 May 1.

1College of Horticulture, Nanjing Agricultural University, 210095 Nanjing, Jiangsu China.

Growth monitoring indicated that the height of 'Kanshu' plants with 'Nantong-xiaofangshi' as an interstock was significantly shorter than that of 'Kanshu' plants with no interstock. A transcriptome analysis of the two graft combinations ('Kanshu'/ and 'Kanshu'/'Nantong-xiaofangshi'/) was conducted to explore the dwarfing genes related to the use of the 'Nantong-xiaofangshi' interstock. Hormone levels and water conductance were also measured in these two graft combinations. The results indicated that the levels of both IAA and GA were lower in 'Kanshu' that had been grafted onto the 'Nantong-xiaofangshi' interstock than in 'Kanshu' with no interstock; additionally, the water conductance was lower in grafts with interstocks than in grafts without interstocks. The expression of and auxin-responsive genes was enhanced in scions grafted on the interstock and was negatively correlated with the IAA content and growth of scions. The expression of , , and genes were also upregulated and associated with a decrease in the level of GA in scions grafted on the interstock. Since one of the unigenes was annotated as in , but was not functionally validated, a functional analysis was conducted in transgenic tobacco. Overexpression of in transgenic plants resulted in a dwarf phenotype that could be recovered by the exogenous application of GA. We conclude that the 'Nantong-xiaofangshi' interstock affects the water conductance and expression of genes related to the metabolism and transduction of IAA and GA in the grafted scion and thus regulates phytohormone levels, producing dwarfing.
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http://dx.doi.org/10.1038/s41438-019-0133-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6491603PMC
May 2019

Skeletal Muscle Lipid Droplets and the Athlete's Paradox.

Cells 2019 03 15;8(3). Epub 2019 Mar 15.

School of Kinesiology and Health, Capital University of Physical Education and Sports, Beijing 100191, China.

The lipid droplet (LD) is an organelle enveloped by a monolayer phospholipid membrane with a core of neutral lipids, which is conserved from bacteria to humans. The available evidence suggests that the LD is essential to maintaining lipid homeostasis in almost all organisms. As a consequence, LDs also play an important role in pathological metabolic processes involving the ectopic storage of neutral lipids, including type 2 diabetes mellitus (T2DM), atherosclerosis, steatosis, and obesity. The degree of insulin resistance in T2DM patients is positively correlated with the size of skeletal muscle LDs. Aerobic exercise can reduce the occurrence and development of various metabolic diseases. However, trained athletes accumulate lipids in their skeletal muscle, and LD size in their muscle tissue is positively correlated with insulin sensitivity. This phenomenon is called the athlete's paradox. This review will summarize previous studies on the relationship between LDs in skeletal muscle and metabolic diseases and will discuss the paradox at the level of LDs.
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http://dx.doi.org/10.3390/cells8030249DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6468652PMC
March 2019

Posttreatment With the Fatty Acid Amide Hydrolase Inhibitor URB937 Ameliorates One-Lung Ventilation-Induced Lung Injury in a Rabbit Model.

J Surg Res 2019 07 26;239:83-91. Epub 2019 Feb 26.

Department of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China. Electronic address:

Background: One-lung ventilation (OLV)-induced inflammation is a risk factor for acute lung injury that is responsible for 20% of postoperative pulmonary complications after lung resection. Inflammation is an important trigger for acute lung injury. Fatty acid amide hydrolase (FAAH) is the major enzyme that degrades the endocannabinoid arachidonoylethanolamine (AEA), an important regulator of inflammation, and its downstream metabolites such as arachidonic acid (AA) are also involved in inflammation. Importantly, AEA is also found in lung parenchyma. However, it remains unclear whether pharmacological inhibition of FAAH inhibitor using compounds such as URB937 can attenuate OLV-induced lung injury.

Materials And Methods: New Zealand white rabbits were anesthetized to establish a modified OLV-induced lung injury model. Twenty-four male rabbits were randomly divided into four groups (n = 6): TLV-S (2.5-h two-lung ventilation [TLV] + 1.5 mL/kg saline + 1-h TLV), OLV-S (2.5-h OLV + 1.5 mL/kg saline + 0.5-h OLV + 0.5-h TLV), U-OLV (1.5 mL/kg URB937 + 3.0-h OLV + 0.5-h TLV), and OLV-U (2.5-h OLV + 1.5 mL/kg URB937 + 0.5-h OLV + 0.5-h TLV). Arterial blood gases, lung wet/dry ratio, and lung injury score of the nonventilated lungs were measured. The levels of AEA, AA, prostaglandin I2 (PGI2), thromboxane A2 (TXA2), and leukotriene B4 (LTB4) in the nonventilated lung were also quantified.

Results: The arterial oxygenation index (PaO/FiO) decreased after 0.5-h OLV in the three OLV groups. The PaO/FiO in the OLV-U group was better than that in the OLV-S and U-OLV groups and was accompanied with reductions in the wet/dry ratio and lung injury scores of the nonventilated lungs. The FAAH inhibitor URB937 administered not before but 2.5 h after OLV attenuated OLV-induced lung injury by increasing AEA levels and reducing the levels of downstream metabolites including AA, PGI2, TXA2, and LTB4.

Conclusions: Posttreatment with the FAAH inhibitor URB937 attenuated OLV-induced lung injury in rabbits and was associated with increased AEA levels and decreased levels of AA and its downstream metabolites.
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http://dx.doi.org/10.1016/j.jss.2019.01.009DOI Listing
July 2019

Molecular characteristics and virulence gene profiles of Staphylococcus aureus causing bloodstream infection.

Braz J Infect Dis 2018 Nov - Dec;22(6):487-494. Epub 2018 Dec 27.

Wuhan University, Zhongnan Hospital, Department of Laboratory Medicine, Wuhan, China. Electronic address:

Background: The rate of methicillin-resistant Staphylococcus aureus (MRSA) among the total of S. aureus isolates decreased to 35.3% in 2017 in China. It is unclear whether the molecular characteristics of S. aureus isolates have changed as the rate decreased.

Objective: This study aimed to investigate the molecular characteristics and virulence genes profile of S. aureus isolates causing bloodstream infection and analyze the correlation between the prevalence rates of the common sequence types and MRSA.

Methods: A total of 112 S. aureus strains from eight hospitals of four cities, including 32 MRSA isolates, were identified and evaluated through multilocus sequence typing, spa typing, and determination of virulence genes.

Results: Twenty-five STs were identified, of which ST5 (21.4%) was the most prevalent, whereas the prevalence of ST239 correlated with the rate of MRSA among all S. aureus isolates. Forty-six spa types were identified, of which t2460 (14.3%) was the most common. clfa, hla, seb, fnbA and hlb were the prevailing virulence genes. 81.3% MRSA and 45.0% methicillin-sensitive S. aureus (MSSA) isolates harbored six or more tested virulence genes. ST5-t2460, seldom noted in bloodborne S. aureus isolates in China, was the most common clone. The prevalence of harboring six or more virulence genes in ST5-t2460 and ST188-t189 were 93.8% and 8.3%, respectively.

Conclusion: ST5-t2460 was the most common clone in S. aureus causing bloodstream infection followed by ST188-t189, which had never been noted in China before. Moreover, ST5-t2460 harbored more virulence genes than ST188-t189, and the prevalence of ST239 clone decreased with the proportion of MRSA among all S. aureus isolates.
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http://dx.doi.org/10.1016/j.bjid.2018.12.001DOI Listing
March 2020

α7 Nicotinic acetylcholine receptor contributes to the alleviation of lung ischemia-reperfusion injury by transient receptor potential vanilloid type 1 stimulation.

J Surg Res 2018 10 23;230:164-174. Epub 2018 Jun 23.

Department of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China. Electronic address:

Background: Activation of transient receptor potential vanilloid type 1 (TRPV1) decreases lung ischemia-reperfusion injury (LIRI) in rabbits and rats. Stimulation of α7 nicotinic acetylcholine receptors (α7nAChRs) protects against lung injury. Here we examined whether α7nAChRs contribute to TRPV1-mediated protection against LIRI.

Methods: Wild-type (WT) and TRPV1-knockout (KO) mice were subjected to 1-h lung ischemia by clamping left hilum, followed by 2-h reperfusion. WT or KO mice were pretreated with vehicle, TRPV1 agonist capsaicin, TRPV1 antagonist capsazepine, α7nAChR antagonist methyllycaconitine, or α7nAChR agonist PNU-282987. Arterial blood and lung tissues were obtained for blood gas, lung wet-to-dry weight ratio, interleukin (IL)1β, IL6, tumor necrosis factor-α (TNF-α), apoptosis-related proteins (caspases, Bax, Fas), and pathologic scoring.

Results: Capsaicin pretreatment reduced wet-to-dry ratio, pathologic score, alveolar-arterial oxygen gradient (A-aDO), and IL1β, IL6, and TNFα levels in WT mice, with no effects in KO mice. This reduction was reversed by TRPV1 blockade. Furthermore, α7nAChR blockade before capsaicin exacerbated LIRI as evidenced by enhanced alveolar-arterial oxygen gradient, pathologic score, and IL1β, IL6, and TNFα levels, while α7nAChR agonist pretreatment under TRPV1 blockade showed opposite changes. Capsaicin also decreased cleaved caspase-3, caspase-3/9, and Bax protein expression, effects abolished by TRPV1 blockade. Similarly, α7nAChR blockade diminished capsaicin-induced downregulation of apoptotic proteins, and α7nAChR activation decreased expression levels even under TRPV1 blockade.

Conclusions: TRPV1 activation alleviates LIRI, partially dependent on α7nAChR activity. The α7nAChR stimulation with or without existence of TRPV1 alleviates LIRI. Thus, α7nAChR is involved in the pathway of TRPV1-mediated protection against LIRI and the specific mechanism remains to be revealed.
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http://dx.doi.org/10.1016/j.jss.2018.05.038DOI Listing
October 2018

The effect of graphene oxide on adventitious root formation and growth in apple.

Plant Physiol Biochem 2018 Aug 30;129:122-129. Epub 2018 May 30.

College of Horticulture, Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, PR China. Electronic address:

Graphene, a new type of nanomaterial, has unique physical properties and important potential biological applications. However, few studies have been conducted on the environmental impact of graphene. Therefore, to explore the effect of graphene on plants, three-week-old, tissue-cultured 'Gala' apple plants (Malus domestica) were treated with different concentrations (0, 0.1, 1, 10 mg/L) of graphene oxide (GO) and examined after 40 days. Results indicated that adventitious root length, moisture content and the number of lateral roots were all inhibited by 0.1-10 mg/L GO. At 0.1 and 1 mg/L GO, however, the number of adventitious roots and the rooting rate exhibited a significant increase, relative to the control (no GO). Treatment with GO increased the activities of oxidative stress enzymes including catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) in the apple plants, relative to controls. Malondialdehyde (MDA) levels were also significantly decreased at 10 mg/L GO. Treatment of apple plantlets with 0.1 mg/L GO increased the transcript abundance of auxin efflux carrier (PIN7, ABCB1) genes and auxin influx carrier (LAX2, LAX3) genes but inhibited the transcript levels of the ARR3 gene, which involved in cytokinin biosynthesis. Additionally, the transcript levels of ARRO1, ARF19, and TTG1, which play roles in the formation of adventitious roots, lateral roots, and root hairs, respectively, were all decreased in response to treatment with 1 and 10 mg/L GO. Collectively, the results indicate that treatment of 'Gala' apple plants with 0.1 mg/L GO had a positive effect on root formation but a negative effect on root growth. This response may be related to the negative impact of GO on cellular structure and function.
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http://dx.doi.org/10.1016/j.plaphy.2018.05.029DOI Listing
August 2018

Reply to Abrams et al. and to Duggal and Krishnan.

Am J Respir Crit Care Med 2018 07;198(1):141-142

1 University of Toronto Toronto, Canada.

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http://dx.doi.org/10.1164/rccm.201802-0371LEDOI Listing
July 2018

Unproven and Expensive before Proven and Cheap: Extracorporeal Membrane Oxygenation versus Prone Position in Acute Respiratory Distress Syndrome.

Am J Respir Crit Care Med 2018 04;197(8):991-993

1 Department of Critical Care Medicine and Anesthesia, Hospital for Sick Children, University of Toronto, Toronto, Canada.

We identified 810 reports that describe extracorporeal membrane oxygenation (ECMO) in acute respiratory distress syndrome (ARDS), and 61 fulfilled our inclusion criteria. The authors of 26 (43%) reports responded to e-mail requests for confirmation (or clarification). Based on the aggregate (published and e-mailed) information, unambiguous data were available relating to 17 papers. These 17 papers represented 672 patients with ARDS who were cannulated with venovenous ECMO; of these patients, 208 (31%) received a trial of prone positioning before ECMO, and 464 (69%) did not. A key randomized controlled trial was published in 2013 that reported a survival benefit associated with prone positioning (N Engl J Med 2013;368:2159-2168). The proportion of all venovenous ECMO patients in whom prone positioning was used before ECMO was lower in studies published after 2013 (84 of 452 [19%]) than in those published before 2013 (116 of 210 [55%]) (P < 0.05). These data suggest a systematic bias in the reporting of outcomes after ECMO in the literature. The vast majority of reported patients who received ECMO did not first receive therapy that (in contrast to ECMO) is simple, cheap, and of proven benefit; therefore, inferences about the efficacy of ECMO in ARDS are of limited use.
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http://dx.doi.org/10.1164/rccm.201711-2216CPDOI Listing
April 2018

A rare case of Marchiafava-Bignami disease: Extracallosal lesions involving bilateral medipeduncle.

Neurol India 2017 May-Jun;65(3):642-643

Department of Neurology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.

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http://dx.doi.org/10.4103/neuroindia.NI_365_16DOI Listing
July 2019

Deletion of PDK1 causes cardiac sodium current reduction in mice.

PLoS One 2015 17;10(3):e0122436. Epub 2015 Mar 17.

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

Background: The AGC protein kinase family regulates multiple cellular functions. 3-phosphoinositide-dependent protein kinase-1 (PDK1) is involved in the pathogenesis of arrhythmia, and its downstream factor, Forkhead box O1 (Foxo1), negatively regulates the expression of the cardiac sodium channel, Nav1.5. Mice are known to die suddenly after PDK1 deletion within 11 weeks, but the underlying electrophysiological bases are unclear. Thus, the aim of this study was to investigate the potential mechanisms between PDK1 signaling pathway and cardiac sodium current.

Methods And Results: Using patch clamp and western blotting techniques, we investigated the role of the PDK1-Foxo1 pathway in PDK1 knockout mice and cultured cardiomyocytes. We found that PDK1 knockout mice undergo slower heart rate, prolonged QRS and QTc intervals and abnormal conduction within the first few weeks of birth. Furthermore, the peak sodium current is decreased by 33% in cells lacking PDK1. The phosphorylation of Akt (308T) and Foxo1 (24T) and the expression of Nav1.5 in the myocardium of PDK1-knockout mice are decreased, while the nuclear localization of Foxo1 is increased. The role of the PDK1-Foxo1 pathway in regulating Nav1.5 levels and sodium current density was verified using selective PDK1, Akt and Foxo1 inhibitors and isolated neonatal rat cardiomyocytes.

Conclusion: These results indicate that PDK1 participates in the dysregulation of electrophysiological basis by regulating the PDK1-Foxo1 pathway, which in turn regulates the expression of Nav1.5 and cardiac sodium channel function.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0122436PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4363661PMC
February 2016

HSPA12B inhibits lipopolysaccharide-induced inflammatory response in human umbilical vein endothelial cells.

J Cell Mol Med 2015 Mar 24;19(3):544-54. Epub 2014 Dec 24.

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

Heat shock protein A12B (HSPA12B) is a newly discovered member of the HSP70 protein family. This study investigated the effects of HSPA12B on lipopolysaccharide (LPS)-induced inflammatory responses in human umbilical vein endothelial cells (HUVECs) and the possible mechanisms involved. A HUVECs inflammatory model was induced by LPS. Overexpression of HSPA12B in HUVECs was achieved by infection with recombinant adenoviruses encoding green fluorescence protein-HSPA12B. Knockdown of HSPA12B was achieved by siRNA technique. Twenty four hours after virus infection or siRNA transfection, HUVECs were stimulated with 1 μg/ml LPS for 4 hrs. Endothelial cell permeability ability was determined by transwell permeability assay. The binding rate of human neutrophilic polymorphonuclear leucocytes (PMN) with HUVECs was examined using myeloperoxidase assay. Cell migrating ability was determined by the wound-healing assay. The mRNA and protein expression levels of interested genes were analyzed by RT-qPCR and Western blot, respectively. The release of cytokines interleukin-6 and tumour necrosis factor-α was measured by ELISA. HSPA12B suppressed LPS-induced HUVEC permeability and reduced PMN adhesion to HUVECs. HSPA12B also inhibited LPS-induced up-regulation of adhesion molecules and inflammatory cytokine expression. By contrast, knockdown of HSPA12B enhanced LPS-induced increases in the expression of adhesion molecules and inflammatory cytokines. Moreover, HSPA12B activated PI3K/Akt signalling pathway and pharmacological inhibition of this pathway by Wortmannin completely abrogated the protection of HSPA12B against inflammatory response in HUVECs. Our results suggest that HSPA12B attenuates LPS-induced inflammatory responses in HUVECs via activation of PI3K/Akt signalling pathway.
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http://dx.doi.org/10.1111/jcmm.12464DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4369812PMC
March 2015