Publications by authors named "He Duan"

22 Publications

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Correlation between Methylation in Cell-Free DNA and the Prognosis of Cancer Patients: A Systematic Review and Meta-Analysis.

J Oncol 2022 28;2022:3458420. Epub 2022 Apr 28.

Department of the Third General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, 110032 Liaoning Province, China.

Background: Although the effects of methylation of the Ras association domain-containing protein 1 isoform A () gene in cell-free DNA on the outcomes of patients with different types of cancer have been reported, the results are inconsistent.

Objective: : To explore the relationships between methylation in cell-free DNA and the outcomes of cancer patients.

Methods: The PubMed, Embase, and Web of Science databases were searched for papers related to this topic on December 8, 2021. The retrieved articles were screened by two independent researchers, following which the methodological quality of the selected studies was evaluated using the Newcastle-Ottawa Scale. Additionally, hazard ratios were calculated, and publication bias of the studies was determined using Egger's test.

Results: Nine relevant publications involving a combined total of 1254 patients with different types of cancer were included in this study. The combined results of the random effects models yielded a hazard ratio of 1.73 (95% confidence interval: 1.31, 2.29; < 0.001), which suggested there was a significant association between methylation and overall survival, and patients with an methylation status had a significantly increased risk of total death. Moreover, the Egger test result suggested there was no significant publication bias among the included studies.

Conclusions: The methylation of in cell-free DNA in cancer patients was observably associated with an increased risk of poor overall survival.
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http://dx.doi.org/10.1155/2022/3458420DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9071870PMC
April 2022

Association of has_circ_0001944 upregulations with prognosis and cancer progression in patients with colorectal cancer.

Authors:
He Duan Jian Qiu

Discov Oncol 2022 Apr 9;13(1):23. Epub 2022 Apr 9.

Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, No. 4 Chongshan East Road in Huanggu District, Shenyang, 110036, Liaoning, China.

Background: CircRNAs are functional in cancer-related processes and are promising candidates for cancer prognostic biomarkers. The study aimed to evaluate the functional and clinical significance of has_circ_0001944 in colorectal cancer (CRC), including predictive value for overall survival (OS) and recurrence-free survival (RFS), and its effect on cell growth and metastasis.

Methods: This retrospective study included 133 patients with CRC. The expression of has_circ_0001944 in tissues and cells was quantified by real-time quantitative reverse transcription PCR. Receiver operating characteristics and Kaplan-Meier survival analysis were used to assess the significance of has_circ_0001944 as a prognostic marker, and its reliability was validated using multivariate regression analysis. Subsequently, XTT, transwell migration, and modified-transwell invasion assays were used to determine the behavior of the CRC cells in response to has_circ_0001944 inhibition.

Results: Results of the qRT-PCR showed upregulation of has_circ_0001944 in the CRC samples compared to the normal samples. High has_circ_0001944 expression indicated shorter OS and RFS, comes down to poor prognosis. Multivariate regression analysis showed that elevated has_circ_0001944 increased the risk of death or recurrence and is a valuable prognostic factor. Following the has_circ_0001944 inhibition, the proliferation, migration and invasion of the CRC cells were reduced. miR-548b-3p was target miRNA of has_circ_0001944.

Conclusion: Up-regulation of has_circ_0001944 is associated with a poor prognosis of CRC. has_circ_0001944 downregulation can slow the progression of CRC partly by targeting miR-548b-3p.
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http://dx.doi.org/10.1007/s12672-022-00485-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8994801PMC
April 2022

Genome-Guided Discovery of Antifungal Filipins from a Deep-Sea-Derived .

J Nat Prod 2022 02 9;85(2):365-374. Epub 2022 Feb 9.

Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.

Nine new (-, -, , and ; named filipins VI-XIV) and three known (, , and ) filipin-type polyene macrolides were isolated from the deep-sea-derived OUCT16-23 using a genome-guided strategy coupled with bioassay. Their structures were elucidated based on the extensive MS and NMR spectroscopic analyses together with ECD calculations. In an antifungal assay, compounds , , and - showed different degrees of growth inhibition against with minimum inhibitory concentrations (MICs) of 1.56-12.5 μg/mL, by which the alkyl side-chain substitution affecting the activity was preliminarily studied. A biosynthetic pathway to - in OUCT16-23 is also proposed.
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http://dx.doi.org/10.1021/acs.jnatprod.1c00952DOI Listing
February 2022

MgMoO as an anode material for lithium ion batteries and its multi-electron reaction mechanism.

Dalton Trans 2022 Feb 8;51(6):2493-2505. Epub 2022 Feb 8.

School of Physics and Optoelectronics, South China University of Technology, Guangzhou, 510640, P. R. China.

Single-phase magnesium molybdate, MgMoO, is successfully synthesized by a facile sol-gel method. Attributed to the multielectron reaction and the synergistic effect of the elements molybdenum (Mo) and magnesium (Mg), the MgMoO electrode exhibits excellent electrochemical properties. After activation, benefiting from the decrease in particle size and the uniform nanosphere morphology, the MgMoO electrodes can deliver a stable high specific capacity of about 1060 mA h g at a current density of 100 mA g after 600 cycles. Based on the important role of the activation process, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and scan rate cyclic voltammetry (CV) measurement methods were employed to reveal the effect of the activation process on the electrochemical behavior of the electrode material. Furthermore, by combining the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results, we illustrate the lithium storage mechanism of the MgMoO electrode in detail.
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http://dx.doi.org/10.1039/d1dt03971gDOI Listing
February 2022

Profiling and Characterization of microRNAs Responding to Sodium Butyrate Treatment in Gastric Cancer Cells.

Comb Chem High Throughput Screen 2021 Oct 27. Epub 2021 Oct 27.

Department of General Surgery, The Fourth Affiliated Hospital of the China Medical University, Shenyang 110032, Liaoning. China.

Background: Short-chain fatty acids exert anti-cancer effects on tumor cells.

Objective: We aimed to reveal the signaling network altered by butyrate in Gastric Cancer (GC) using small RNA sequencing (sRNA-seq).

Methods: The effects of butyrate on the biological behavior of NCI-N87 and KATO III cells in vitro were assessed by functional assays and half-maximal inhibitory concentrations (IC50) of butyrate in KATO III cells were calculated. sRNA-seq was performed on KATO III cells. Differentially expressed miRNAs (DE-miRNAs) were identified between butyrate treatment and control groups using DESeq2, and miRNA targets were predicted. A protein-protein interaction (PPI) network of DE-miRNA targets was created using Metascape. Key MCODE complexes were identified using the MCODE algorithm and cluster Profiler. The relationship between DE-miRNA and GC overall survival (OS) was evaluated using Kaplan-Meier curves.

Results: Butyrate dose-dependently inhibited NCI-N87 and KATO III cell viability. KATO III cells were more sensitive to butyrate than NCI-N87 cells. Butyrate promoted apoptosis and inhibited KATO III cell migration. Total 324 DE-miRNAs were identified in KATO III cells, and 459 mRNAs were predicted as targets of 83 DE-miRNAs. Two key protein complexes were identified in a PPI network of the 459 targets. A key signaling network responding to butyrate were generated using targets in these key complexes and their miRNA regulators. The DE-miRNAs in the key signaling network were related to the OS of GC.

Conclusion: Butyrate altered the biological behavior of GC cells, which may be achieved by regulating miRNAs and related oncogenic pathways.
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http://dx.doi.org/10.2174/1386207325666211027154207DOI Listing
October 2021

Synthesis of a full range Fe-doped ZnFeCoO and its application as anode material for lithium-ion battery.

Dalton Trans 2021 Nov 2;50(42):15036-15046. Epub 2021 Nov 2.

School of Physics and Optoelectronics, South China University of Technology, Guangzhou, 510640, P. R. China.

Fe-Doped ZnFeCoO ( = 0.00, 0.17, 0.33, 0.47, 0.67, 0.87, 1.17, 1.37, 1.67, 1.87, 2.00) compounds were prepared by a sol-gel method. X-ray diffraction measurements show that Fe-doping does not change the crystal structure of ZnCoO and dopant Fe successfully occupies the 16c Co site. Because of the bigger radius of the doping ion, the cell parameters and cell volumes of ZnFeCoO compounds present an obvious linear increase with increasing Fe content. In addition, attributed to the similar crystal structures for ZnFeO and ZnCoO, a full range (0 ≤ ≤ 2) of ZnFeCoO solid solution phases was obtained. / measurement results show that a small Fe doping content obviously improved the electronic conductivity of the sample. In addition, due to the smaller particles size and uniform particle distribution caused by Fe doping, the lithium ion diffusion coefficient of the sample was increased by 2 orders of magnitude. Based on the improved electronic conductivity combined with the significantly increased lithium-ion diffusion coefficient, a sample with Fe doping content of = 0.33, ZnFeCoO, presents a high reversible specific capacity and excellent rate cycle stability. At a rate of 100 mA g, a relatively high discharge capacity of 850 mA h g can still be obtained after 100 cycles, which is obviously higher than that of pure ZnCoO (only 295 mA h g). Even at a higher discharge rate of 500 mA g, a discharge capacity of 450 mA h g with a capacity retention of nearly 100% was obtained. Based on its excellent electrochemical properties, ZnFeCoO will be a promising anode material for rechargeable lithium-ion batteries.
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http://dx.doi.org/10.1039/d1dt02865kDOI Listing
November 2021

Prognostic Score Model Based on Ten Differentially Methylated Genes for Predicting Clinical Outcomes in Patients with Adenocarcinoma of the Colon.

Cancer Manag Res 2021 28;13:5113-5125. Epub 2021 Jun 28.

Department of General Surgery, The Fourth Affiliated Hospital of the China Medical University, Shenyang, 110032, People's Republic of China.

Purpose: We aimed to screen novel genetic biomarkers for use in a prognostic score (PS) model for the accurate prediction of survival outcomes for patients with colon adenocarcinoma (COAD).

Methods: Gene expression and methylation data were downloaded from The Cancer Genome Atlas database, and the samples were randomly divided into training and validation sets for the screening of differentially methylated genes (DMGs) and differentially expressed genes (DEGs). Co-methylated genes were screened using weighted gene co-expression network analysis. Functional enrichment analysis was performed using the Database for Annotation, Visualization, and Integrated Discovery. Univariate and multivariate Cox regression analyses were performed to identify prognosis-related genes and clinical factors. Receiver operating characteristic curve analysis was carried out to evaluate the predictive performance of the PS model.

Results: In total, 1434 DEGs and 1038 DMGs were screened in the training set, among which 284 were found to be overlapping genes. For 127 of these overlapping genes, the methylation and expression levels were significantly negatively correlated. An optimal signature from 10 DMGs was identified to construct the PS model. Patients with a high PS seemed to have worse outcomes than those with a low PS. Moreover, cancer recurrence and the PS model status were independent prognostic factors.

Conclusion: This PS model based on an optimal 10-gene signature would help in the stratification of patients with COAD and improve the assessment of their clinical outcomes.
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http://dx.doi.org/10.2147/CMAR.S312085DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8254377PMC
June 2021

Expression and prognostic analysis of Rho GTPase-activating protein 11A in lung adenocarcinoma.

Ann Transl Med 2021 May;9(10):872

Department of Radiation Oncology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.

Background: Rho GTPase-activating protein 11A (ARHGAP11A) is a member of the Rho GTPase-activating protein (RhoGAP) subfamily. However, its expression, prognostic significance and clinicopathologic factors correlation in lung adenocarcinoma is still unclear.

Methods: The original gene expression profile, survival data, and clinical information of patients with lung adenocarcinoma (LUAD) were downloaded from The Cancer Genome Atlas (TCGA) database. The expression difference of ARHGAP11A between LUAD tissues and adjacent normal tissues in the TCGA database was analyzed by using R software, and verified by the Oncomine database and immunohistochemical (IHC) assay of LUAD sections. Logistic regression was applied to analyze the relationship between the expression of ARHGAP11A and clinicopathological factors of LUAD. Kaplan-Meier (KM) survival curves and a Cox proportional-hazards model were selected to evaluate the prognostic significance of ARHGAP11A expression. Gene set enrichment analysis (GSEA) software was applied to screen the tumor signaling pathways associated with the low and high expression group of ARHGAP11A in LUAD.

Results: The TCGA database showed that the expression of ARHGAP11A was significantly higher in LUAD tissues than in normal tissues (P<0.001). The up-regulation of ARHGAP11A in LUAD was verified by the Oncomine database (P<0.001) and IHC assay (P<0.001). Logistic regression analysis revealed the high expression of ARHGAP11A to be closely related to age, sex, advanced pathological stage, advanced T stage, and lymph node metastasis. The KM plots based on the TCGA and KM plotter databases indicated that patients with LUAD highly expressing ARHGAP11A had a poorer overall survival (OS) than patients with low expression of ARHGAP11A. Multivariate Cox regression analysis showed that the high expression of ARHGAP11A could be an important independent predictor of a poor prognosis of LUAD [hazards ratio (HR) =1.385; P<0.001]. GSEA indicated that 10 signal pathways were significantly enriched in LUAD samples with the ARHGAP11A expression phenotype.

Conclusions: ARHGAP11A may play a carcinogenic role in the malignant progression of LUAD, and it can be considered as a new independent prognostic factor and potential therapeutic target for LUAD.
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http://dx.doi.org/10.21037/atm-21-2113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8184474PMC
May 2021

The facile synthesis and electrochemical performance of NiVO as a novel anode material for lithium-ion batteries.

Dalton Trans 2021 Jun;50(21):7293-7304

School of Physics and Optoelectronics, South China University of Technology, Guangzhou, 510640, P. R. China.

The single-phase binary nickel vanadate Ni2V2O7 was successfully synthesized by a simple solid-state method to explore novel anode materials for lithium-ion batteries. After an activation process, the Ni2V2O7 electrode exhibited excellent electrochemical performance with a stable, high specific capacity of about 960 mA h g-1 at a current density of 100 mA g-1, which is attributed to the multiple valence states and the synergistic effect of the transition elements V and Ni. Even at a high current density of 2000 mA g-1, a stable specific capacity of about 400 mA h g-1 was still obtained. Considering the influence of the activation process on the electrochemical performance of the Ni2V2O7 electrode, we studied the origin of the excellent electrochemical performance, where the improved lithium diffusion coefficient and increased pseudocapacitive contribution caused by the activation process led to a significant improvement in the electrochemical performance, including rate capacity and cycle stability. By combining in situ X-ray diffraction (XRD) and ex situ X-ray photoelectron spectroscopy (XPS) methods, for the first time, we illustrate the detailed lithium storage mechanism of the Ni2V2O7 electrode during the lithium insertion/extraction process.
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http://dx.doi.org/10.1039/d1dt00983dDOI Listing
June 2021

Metformin Suppresses the Proliferation and Promotes the Apoptosis of Colon Cancer Cells Through Inhibiting the Expression of Long Noncoding RNA-UCA1.

Onco Targets Ther 2020 14;13:4169-4181. Epub 2020 May 14.

Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, People's Republic of China.

Purpose: LncRNA-UCA1 has been proven to facilitate the proliferation and metastasis of colon cancer. Whether metformin inhibits the progression of colon cancer by suppressing lncRNA-UCA1 remains unknown. In this research, we aimed to explore the role of Metformin playing in pathogenesis of colon cancer.

Materials And Methods: Using qRT-PCR, we measured the expression of five tumor-promoting lncRNAs in SW480 and SW620 colon cancer cells. Then, we conducted Western blotting and immunohistochemistry to evaluate the effects of MET or UCA1 knockdown or the combined MET+ UCA1 knockdown on the activities of the PI3K/AKT and ERK pathways in vitro and in tumor tissues obtained from tumor-bearing nude mice.

Results: The results from CCK-8 assays showed that MET dose-dependently and time-dependently inhibited the viability of the colon cancer cells in vitro. Flow cytometry revealed that MET promoted the apoptosis of the SW480 and SW620 cells. qRT-PCR showed that lncRNA-UCA1 had the highest expression among the five lncRNAs. Suppressing UCA1 expression by siRNA or shRNA could further enhance the metformin-mediated anticancer effects against colon cancer in vitro and in vivo. Metformin decreased the UCA1 expression and further inhibited the proliferation and promoted the apoptosis of the colon cancer cells, which were associated with inactivation of the PI3K/AKT and ERK signaling pathways in vitro and in the tumor tissues obtained from the mice.

Conclusion: These results indicated that metformin has potential anticancer properties and revealed the anticancer mechanisms of metformin against colon cancer via regulating lncRNA-UCA1.
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http://dx.doi.org/10.2147/OTT.S245091DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7234977PMC
May 2020

LncRNA TUBA4B functions as a competitive endogenous RNA to inhibit gastric cancer progression by elevating PTEN via sponging miR-214 and miR-216a/b.

Cancer Cell Int 2019 7;19:156. Epub 2019 Jun 7.

Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, 4 Chongshan East Street, Shenyang, 110032 Liaoning People's Republic of China.

Background: Emerging evidence demonstrates that long non-coding RNA (lncRNA) is an important regulator in tumorigenesis and development. Tubulin Alpha 4B (TUBA4B), a novel lncRNA, was recently proposed as a tumor suppressor in several human cancers. However, its role in gastric cancer (GC) remains unclear. In this study, we aimed to investigate the expression level, clinical implication, biological function and potential regulatory mechanism of TUBA4B in GC.

Methods: qRT-PCR was employed to detect the expression of TUBA4B in GC tissues, cell lines and plasma. In vitro and in vivo experiments were carried out using colony formation/CCK-8/transwell invasion/cell apoptosis assay and xenograft tumor model, respectively. mRNA sequencing was used to identify the TUBA4B-related downstream genes.

Results: TUBA4B was significantly decreased in GC tissues, cells and plasma. Low TUBA4B was positively correlated with larger tumor size, lymph node metastasis and advanced TNM stage. Moreover, TUBA4B was identified as an effective biomarker for the diagnosis and prognosis of patients with GC. Functionally, ectopic expression of TUBA4B inhibited GC cell proliferation, invasion and induced apoptosis in vitro as well as dampened tumor growth and metastasis in vivo. Furthermore, TUBA4B was found to be a competitive endogenous RNA (ceRNA) that could physically bind to and sequester miR-214 and miR-216a/b to increase the expression of their common downstream target PTEN, resulting in inactivation of PI3K/AKT signaling pathway, thereby retarding GC progression.

Conclusion: Our data highlight the compelling regulatory role of TUBA4B in GC, and reactivation of TUBA4B may be a promising therapeutic avenue for GC patients.
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http://dx.doi.org/10.1186/s12935-019-0879-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6556040PMC
June 2019

A novel circular RNA circ-ZNF652 promotes hepatocellular carcinoma metastasis through inducing snail-mediated epithelial-mesenchymal transition by sponging miR-203/miR-502-5p.

Biochem Biophys Res Commun 2019 06 16;513(4):812-819. Epub 2019 Apr 16.

Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, PR China. Electronic address:

Circular RNA (circRNA), a special class of non-coding RNA, is increasingly being realized as a critical regulator in human diseases, including carcinomas. However, its role in hepatocellular carcinoma (HCC) metastasis remains largely unknown. Herein, we enrolled three Gene Expression Omnibus (GEO) databases and screened and identified a novel circRNA, circ-ZNF652 (hsa_circ_0003258), which was significantly upregulated in HCC tissues and cell lines. Importantly, HCC patients with high circ-ZNF652 expression were more prone to vascular invasion, intrahepatic metastasis, distant metastasis, and poor outcome. Subsequent functional experiments showed that depletion of circ-ZNF652 dramatically suppressed the migratory and invasive capabilities of HCC cells in vitro as well as tumor metastasis in vivo by inhibiting the process of epithelial-mesenchymal transition (EMT). Mechanistically, circ-ZNF652 could physically interact with miR-203 and miR-502-5p to increase the expression of their common target gene Snail (a key transcription factor that triggers EMT), thereby promoting the metastasis of HCC. In turn, the upregulated Snail was capable of binding to the E-box motif (CAGGTG) on the promoter of circ-ZNF652 to elevate circ-ZNF652 expression. Collectively, our findings suggest that circ-ZNF652 is a novel driver of EMT and unveil the important regulatory role of circ-ZNF652/miR-203/miR-502-5p/Snail feedback loop in HCC metastasis.
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http://dx.doi.org/10.1016/j.bbrc.2019.03.214DOI Listing
June 2019

Diagnostic Assessment of septin9 DNA Methylation for Colorectal Cancer Using Blood Detection: A Meta-Analysis.

Pathol Oncol Res 2019 Oct 28;25(4):1525-1534. Epub 2018 Nov 28.

Department of the Third general surgery, The Fourth Affiliated Hospital of the China Medical University, No. 4 Chongshan Road, Shenyang, 110032, China.

This meta-analysis aimed to assess the diagnostic efficiency of blood-based septin 9 (SEPT9) methylation assay for the detection of colorectal cancer (CRC). Studies were searched in the Springer, Wiley, Cochrane Library, PubMed, Ovid, Embase, Web of Science, China BioMedicine, Wanfang and China National Knowledge Infrastructure databases until July 2017. Methodological quality assessment was performed based on the guidelines of the Quality Assessment of Diagnostic Accuracy Studies. According to 1/3 and 2/3 algorithms, the meta-analyses for the diagnostic effect of SEPT9 in CRC were compared with healthy subjects and subjects with polyps, adenoma, and non-CRC, respectively. The random effects model was applied and publication bias was evaluated. The included 29 studies comprised 10,486 subjects (3202 patients with CRC and 7284 controls). In comparison with healthy subjects, the pooled sensitivity with 95% confidence intervals (CIs) of SEPT9 methylation for the diagnosis of CRC was 0.74 (95% CI: 0.61-0.84) in the 1/3 algorithm group, whereas the specificity was 0.96 (95% CI: 0.95-0.97) in the 2/3 algorithm group. Additionally, positive likelihood ratio was less than 10 and negative likelihood ratio more than 0.1 in the 2/3 algorithm group for patients with CRC vs. polyps and adenoma. The P value of Deeks' funnel plot was 0.36, suggesting that there was no publication bias. SEPT9 methylation can be used to diagnose CRC in healthy individuals under the 2/3 algorithm. The determination of SEPT9 methylation does not distinguish well between CRC and polyps or adenoma.
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http://dx.doi.org/10.1007/s12253-018-0559-5DOI Listing
October 2019

An ATP-Dependent Ligase with Substrate Flexibility Involved in Assembly of the Peptidyl Nucleoside Antibiotic Polyoxin.

Appl Environ Microbiol 2018 07 18;84(13). Epub 2018 Jun 18.

Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, and School of Pharmaceutical Sciences, Wuhan University, Wuhan, China

Polyoxin (POL) is an unusual peptidyl nucleoside antibiotic, in which the peptidyl moiety and nucleoside skeleton are linked by an amide bond. However, their biosynthesis remains poorly understood. Here, we report the deciphering of PolG as an ATP-dependent ligase responsible for the assembly of POL. A mutant is capable of accumulating multiple intermediates, including the peptidyl moiety (carbamoylpolyoxamic acid [CPOAA]) and the nucleoside skeletons (POL-C and the previously overlooked thymine POL-C). We further demonstrate that PolG employs an ATP-dependent mechanism for amide bond formation and that the generation of the hybrid nucleoside antibiotic POL-N is also governed by PolG. Finally, we determined that the deduced ATP-binding sites are functionally essential for PolG and that they are highly conserved in a number of related ATP-dependent ligases. These insights have allowed us to propose a catalytic mechanism for the assembly of peptidyl nucleoside antibiotic via an acyl-phosphate intermediate and have opened the way for the combinatorial biosynthesis/pathway engineering of this group of nucleoside antibiotics. POL is well known for its remarkable antifungal bioactivities and unusual structural features. Actually, elucidation of the POL assembly logic not only provides the enzymatic basis for further biosynthetic understanding of related peptidyl nucleoside antibiotics but also contributes to the rational generation of more hybrid nucleoside antibiotics via synthetic biology strategy.
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http://dx.doi.org/10.1128/AEM.00501-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6007123PMC
July 2018

Mo Doping in LiVO Anode for Li-Ion Batteries: Significantly Improve the Reversible Capacity and Rate Performance.

ACS Appl Mater Interfaces 2017 Aug 9;9(33):27688-27696. Epub 2017 Aug 9.

Department of Physics, South China University of Technology , Guangzhou, 510640, P. R. China.

Consider the almost insulator for pure LiVO with a band gap of 3.77 eV, to significantly improve the electrical conductivity, the novel LiVMoO (x = 0.00, 0.01, 0.02, 0.05, and 0.10) anode materials were prepared successfully by simple sol-gel method. Our calculations show that, by substitute Mo for V, the extra electron occupied the V 3p empty orbital and caused the Fermi level shift up into the conduction band, where the Mo-doped LiVO presents electrical conductor. The V/I curve measurements show that, by Mo doping in V site, the electronic conductivity of the LiVO was increased by 5 orders of magnitude. And thence the polarization was obviously reduced. EIS measurement results indicated that by Mo-doping a higher lithium diffusion coefficient can be obtained. The significantly increased electronic conductivity combined the higher lithium diffusion coefficient leads to an obvious improvement in reversible capacity and rate performance for the Mo-doped LiVO. The resulting LiVMoO (x = 0.01) material exhibited the excellent rate capability. At a high rate 5 C, a big discharge capacity of the initial discharge capacity 439 mAh/g can be obtained, which is higher than that of pure LiVO (only 166 mAh/g), and after 100 cycles the mean capacity fade is only 0.06% per cycle.
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http://dx.doi.org/10.1021/acsami.7b06459DOI Listing
August 2017

Effects of supplementation with selenium, as selenized yeast, in a healthy male population from New Zealand.

Nutr Cancer 2013 ;65(3):355-66

Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.

Selenium (Se) supplementation was tested in a group of healthy men from Auckland, New Zealnd with selenized yeast (Selplex, 200 μg/day) as the supplementation mode. A set of biomarkers, including DNA damage levels and seleno-antioxidant enzyme levels, were evaluated at pre- and postsupplementation time points. Supplementation produced significant increases in serum Se levels, red blood cell (RBC) thioredoxin reductase (TR) activity and peroxide-induced DNA damage, when the mean baseline serum Se level was 110 ng/ml. Those with higher baseline serum Se levels gained less serum Se and showed a significant reduction of RBC glutathione peroxidase (GPx) activity by supplementation. The optimum benefits of supplementation on DNA stability are observed when the serum Se level reaches between >120 and <160 ng/ml. However, the most significant observation was that those with highest baseline DNA damage benefit the most from Se supplementation, whereas those having lower baseline DNA damage are disadvantaged. A dose of 200 μg/day selenized yeast was also shown to be a safer supplementation option compared to a similar dose of selenomethionine (SeMet). This study highlights the requirement for prestratification of a population by standing serum Se level and baseline DNA damage level, before any Se supplementation is carried out.
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http://dx.doi.org/10.1080/01635581.2013.760743DOI Listing
September 2013

Prostate disease risk factors among a New Zealand cohort.

J Nutrigenet Nutrigenomics 2012 26;5(6):339-51. Epub 2013 Jan 26.

Auckland Cancer Society Research Centre, Discipline of Nutrition, Faculty of Medical and Health Sciences, The University of Auckland, and Urology Department, Auckland Hospital, Auckland, New Zealand.

Background: Prostate cancer is a leading public health burden worldwide, and in New Zealand it is the most commonly registered cancer and the third leading cause of cancer deaths among males. Genetic variability and its associations with diet, demographic and lifestyle factors could influence the risk of this disease.

Methods: The single nucleotide polymorphisms (SNPs) within a group of antioxidant genes and related markers were tested between patient and control cohorts, adjusted for significant differences between basic lifestyle and demographic characteristics.

Results: Increasing age, smoking and low serum selenium levels were significantly associated with an increased risk for prostate disease. Alcohol consumption increased the glutathione peroxidase (GPx) activity. A significant reduction in alcohol consumption was recorded with prostate disease. Three SNPs, namely GPx1 rs1050450, SEL15 rs5845 and CAT rs1001179, were significantly associated with prostate disease risk. A cumulative risk of prostate cancer was noted with 6 risk alleles. A lower GPx activity was recorded with prostate disease compared to the controls. However, the GPx1 rs1050450 allele T in association with prostate cancer recorded a significantly higher GPx activity compared to the controls.

Conclusions: These data point to a possibility of identifying individuals at risk of prostate cancer for better management purposes.
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http://dx.doi.org/10.1159/000346279DOI Listing
September 2013

Serum selenium and single-nucleotide polymorphisms in genes for selenoproteins: relationship to markers of oxidative stress in men from Auckland, New Zealand.

Genes Nutr 2012 Apr 3;7(2):179-90. Epub 2011 Dec 3.

Auckland Cancer Society Research Centre, FM&HS, The University of Auckland, Auckland, New Zealand.

There is controversy as to the recommended daily intake of selenium (Se), and whether current New Zealand diets are adequate in this nutrient. Various functional single-nucleotide polymorphisms (SNPs) polymorphisms may affect the efficacy of Se utilisation. These include the glutathione peroxidases GPx1 rs1050450, GPx4 rs713041, as well as selenoproteins SEPP1 rs3877899, SEL15 rs5845, SELS rs28665122 and SELS rs4965373. This cross-sectional study measured serum Se levels of 503 healthy Caucasian men in Auckland, New Zealand, between ages 20-81. The Se distribution was compared with activities of the antioxidant enzymes glutathione peroxidase and thioredoxin reductase, and DNA damage as measured by the single cell gel electrophoresis assay, both without and with a peroxide-induced oxidative challenge. Serum Se was measured using inductively coupled plasma-dynamic reaction cell-mass spectrometry, while selenoprotein SNPs were estimated using TaqMan(®) SNP genotyping assays. While antioxidant enzyme activities and DNA damage recorded after a peroxide challenge increased with increasing serum selenium, the inherent DNA damage levels in leukocytes showed no statistically significant relationship with serum selenium. However, these relationships and dietary Se requirements at the individual level were modified by several different SNPs in genes for selenoproteins. The GPx1 rs1050450 C allele was significantly associated with GPx activity. Significant correlations between serum Se level and GPX activity were seen with all genotypes except for homozygous minor allele carriers, while the GPx1 rs1050450 CT genotype showed the highest correlation. Several genotypes showed significant correlations between serum Se and TR activity with SEPP1 rs3877899 GG genotype showing the highest correlation. A significant decreasing trend in DNA damage with increasing serum Se was seen among GPx1 rs1050450 CC and GPx4 rs713041 TT genotype carriers up to a serum Se level of 116 and 149 ng/ml, respectively. In the absence of this genetic information, we would recommend a serum Se concentration in the region of 100-150 ng/ml as providing a useful compromise.
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http://dx.doi.org/10.1007/s12263-011-0259-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3316745PMC
April 2012

Genetic factors in chronic inflammation: single nucleotide polymorphisms in the STAT-JAK pathway, susceptibility to DNA damage and Crohn's disease in a New Zealand population.

Mutat Res 2010 Aug 28;690(1-2):108-15. Epub 2010 Jan 28.

Discipline of Nutrition, FM&HS, The University of Auckland, Auckland, New Zealand; Nutrigenomics New Zealand, New Zealand.

The Signal Transducers and Activators of Transcription (STAT)-Janus kinase (JAK) pathway controls signal transduction between cell surface receptors and the nucleus. Two members of that pathway, STAT3 and JAK2, enhanced the risk of Crohn's disease (CD) in recent genome-wide association studies. We replicated these findings in a New Zealand Caucasian case-control cohort, by genotyping two single nucleotide polymorphisms (SNPs) in STAT3 (rs744166(G>A) and rs3816769(C>T)) and rs10758669(A>C) in JAK2, in 302 CD patients and 382 controls. For STAT3, there was a significant decrease in the frequency of the G allele of rs744166 and the C allele of rs3816769 in CD patients as compared with controls (OR=0.76, 95% CI=0.61-0.95, p=0.013; OR=0.71, 95% CI=0.56-0.89, p=0.003). For the JAK2 rs10758669 polymorphism, the homozygous C/C or heterozygous A/C genotypes increased the risk of having CD as compared with the homozygous A/A (OR=1.76, 95% CI=1.26-2.45 and OR=2.36, 95% CI=1.44-3.86, respectively, p=0.0003). Variant alleles in either gene significantly modified the likelihood of inflammatory disease in a colonic location, and of developing extra-intestinal manifestations. The JAK2 variant also strongly enhanced the risk of ileocolonic disease, with stricturing or ileal/stricturing behaviour, requiring a bowel resection. We further studied a subset of our control population, stratified for JAK2 rs10758669 and/or STAT3 rs3816769 genotype. Carrying either the JAK2 or STAT3 IBD risk allele was associated with significantly enhanced susceptibility to DNA damage, as estimated by comet assays in peripheral blood leukocytes, with or without a subsequent oxidative challenge. That is, both risk alleles enhance genomic instability. The JAK2 SNP is part of a haplotype previously associated with enhanced susceptibility to myeloproliferative neoplasms, but functional consequences of the STAT3 variant had not been previously demonstrated. It will be of interest to follow up CD patients carrying either JAK2 or STAT3 risk alleles for development of further secondary effects, including cancer.
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http://dx.doi.org/10.1016/j.mrfmmm.2010.01.017DOI Listing
August 2010

[Effect of intraoperative using cell saver on blood sparing and its impact on coagulation function].

Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2004 Apr;26(2):188-91

Department of Anaesthesia, PUMC Hospital, CAMS and PUMC, Beijing 100730, China.

Objective: To observe the effectiveness of using cell saver (CS) during surgery on blood sparing and its impact on patient's hematology and coagulation function.

Methods: One-hundred and thirty-eight patients undergoing elective surgery were recruited for intraoperative blood salvage using CS. Blood routine, blood chemistry and coagulation function were measured before surgery, after infusion of salvaged blood and postoperative day 1, respectively.

Results: In total, 112,056 ml of packed red blood cells were collected, with a mean value of 812 ml per patient. The percentage of autologous blood transfusion volume to the total blood transfusion volume was from 48% to 89%. Allogenic blood transfusion rate was from 5% to 100%. Compared with the values before surgery, the hemoglobin concentration, platelet count, plasma total protein and fibrinogen concentration decreased significantly after the transfusion of salvaged blood and the first postoperative day (P < 0.05 or P < 0.01), while the prothrombin time was significantly prolonged (P < 0.05).

Conclusions: The use of CS during surgery can, to a certain extent, reduce the requirement of allogenic blood. However, reinfusion of large amount of salvaged blood may affect coagulation function.
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April 2004

[Use of blood salvage machine in oncologic surgeries: a clinical observation of 13 cases].

Zhonghua Yi Xue Za Zhi 2004 Jan;84(2):107-10

Department of Anesthesia, Peking Union Medical College Hospital, Beijing 100730, China.

Objective: To evaluate the effects on blood sparing and risk of hematogenous tumor dissemination of the use of blood salvage machine in oncologic surgeries.

Methods: The clinical data of 13 patients, 6 with malignant tumors and 7 with benign tumors, who received the use of blood salvage machine during oncologic surgeries based on informed consent, were analyzed.

Results: In total 42,575 ml of packed red blood cells were collected during surgery with a mean value of 3 275 ml (400 - 1500 ml) per patient. The average amount of allogenic transfusion per patient was 1 530 ml (0 - 8,000 ml). The number of blood salvage machine use in oncologic surgeries accounted for 8.6% (13/152) of the total number of blood salvage machine use in surgeries in that period. The perioperative mortality rate of the oncologic surgeries with the use of blood salvage machine was 7.7% (1/13). The post-operative metastasis rate of liver and lung was 15.4% (2/13).

Conclusion: The use of blood salvage machine during oncologic surgeries improves the blood sparing effect. However, it cannot be used routinely, since it may result in hematogenous tumor cell dissemination.
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January 2004

[Influence of obesity on pharmacokinetics and pharmacodynamics of isoflurane].

Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2003 Oct;25(5):615-8

Department of Anesthesiology, PUMC Hospital, CAMS and PUMC, Beijing 100730, China.

Objective: To observe the effect of obesity on pharmacokinetics and pharmacodynamics of isoflurane.

Methods: Twenty-six patients undergoing cholecystectomy were divided into obese group (Group A, BMI > or = 27, n = 13) and normal body weight group (Group N, BMI < or = 24, n = 13) according to body mass index (BMI). All patients were given to the same isoflurane anesthesia. Inspired and end-expired concentrations of isoflurane were monitored and uptake fraction of isoflurane were calculated.

Results: Isoflurane concentrations of vaporizer in Group A [(1.8 +/- 0.3)%] were evidently higher than those in Group N [(1.5 +/- 0.1)%] at all observed points (P < 0.05 or P < 0.01). Uptake fraction of isoflurane in Group A were higher than those in Group N at observed points (P < 0.05, P < 0.01 or P < 0.001), but there were no differences in the time when isoflurane concentration was lowered to 50% and awake time between the two groups after discontinuing inhaling isoflurane.

Conclusions: Obese patients demand higher inspired concentration and uptake of isoflurane than those in normal weight patients but discharge of isoflurane was influenced by obesity within the observed period of (66 +/- 33) min.
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October 2003
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