Publications by authors named "Yanting Liu"

64 Publications

A fast and powerful swimming microrobot with a serrated tail enhanced propulsion interface.

Nanoscale 2018 Nov;10(42):19673-19677

Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.

We demonstrate the use of a swimming microrobot with a serrated tail in the propulsion region to enhance reaction interfaces. A 3D printed tail with multiple catalytic channels and nanointerfaces could reinforce the microrobot, allowing it to reach swimming speeds of ∼1 mm s-1 and enabling it to transport objects with a weight 6500 times that of itself. This research represents a new concept in swimming microrobot design and is expected to benefit a wide range of engineering fields.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c8nr04907fDOI Listing
November 2018

Prolactin-Secreting Lung Adenocarcinoma Metastatic to the Pituitary Mimicking a Prolactinoma: A Case Report.

Neurosurgery 2019 10;85(4):E773-E778

Department of Neurosurgery, Center of Pituitary Tumor, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Background And Importance: Metastasis to the pituitary gland is uncommon in patients with systemic disseminated cancer. Individual articles have reported cases of pituitary metastasis mimicking a prolactinoma, but no case of a prolactin-secreting tumor metastasizing to the pituitary mimicking a prolactinoma has been reported so far.

Clinical Presentation: This article reports a 67-yr-old man with a recent onset of headaches, ophthalmoplegia, hypopituitarism, and hyperprolactinemia who was initially diagnosed with prolactinoma and given bromocriptine in the local hospital. Because of vomiting after taking drugs, he was transferred to our hospital for further diagnosis and treatment. Serum prolactin was elevated up to 1022 ng/mL, and pituitary magnetic resonance imaging revealed a 2.9 × 2.8 × 2.3 cm sellar mass with pituitary apoplexy, for which endoscopic transsphenoidal surgery was performed. Postoperative pathology and western blotting disclosed a prolactin-positive metastatic lung adenocarcinoma. Whole exome sequencing revealed a number of gene mutations including KRAS, PIK3CA, ALK, and CTNNB1. The patient died of deterioration of the lung disease 3 mo after the initial diagnosis.

Conclusion: To the best of our knowledge, this is the first report of a prolactin-secreting tumor metastasizing to the pituitary mimicking a prolactinoma as confirmed by both immunohistochemistry and western blot. Prolactin secretion is rare and elusive, and may associate with specified gene mutations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/neuros/nyy386DOI Listing
October 2019

Synthesis of 1,4-Cyclohexanedimethanol, 1,4-Cyclohexanedicarboxylic Acid and 1,2-Cyclohexanedicarboxylates from Formaldehyde, Crotonaldehyde and Acrylate/Fumarate.

Angew Chem Int Ed Engl 2018 06 8;57(23):6901-6905. Epub 2018 May 8.

Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, 116023, China.

Valuable polyester monomers and plasticizers-1,4-cyclohexanedimethanol (CHDM), 1,4-cyclohexanedicarboxylic acid (CHDA), and 1,2-cyclohexanedicarboxylates-have been prepared by a new strategy. The synthetic processes involve a proline-catalyzed formal [3+1+2] cycloaddition of formaldehyde, crotonaldehyde, and acrylate (or fumarate). CHDM is produced after a subsequent hydrogenation step over a commercially available Cu/Zn/Al catalyst and a one-pot hydrogenation/oxidation/hydrolysis process yields CHDA, whereas 1,2-cyclohexanedicarboxylate is obtained by a Pd/C-catalyzed tandem decarbonylation/hydrogenation step.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/anie.201801287DOI Listing
June 2018

New molecular method to detect denitrifying anaerobic methane oxidation bacteria from different environmental niches.

J Environ Sci (China) 2018 Mar 1;65:367-374. Epub 2017 May 1.

School of Environment, Tsinghua University, Beijing 100084, China; Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China.

The denitrifying anaerobic methane oxidation is an ecologically important process for reducing the potential methane emission into the atmosphere. The responsible bacterium for this process was Candidatus Methylomirabilis oxyfera belonging to the bacterial phylum of NC10. In this study, a new pair of primers targeting all the five groups of NC10 bacteria was designed to amplify NC10 bacteria from different environmental niches. The results showed that the group A was the dominant NC10 phylum bacteria from the sludges and food waste digestate while in paddy soil samples, group A and group B had nearly the same proportion. Our results also indicated that NC10 bacteria could exist in a high pH environment (pH9.24) from the food waste treatment facility. The Pearson relationship analysis showed that the pH had a significant positive relationship with the NC10 bacterial diversity (p<0.05). The redundancy analysis further revealed that the pH, volatile solid and nitrite nitrogen were the most important factors in shaping the NC10 bacterial structure (p=0.01) based on the variation inflation factors selection and Monte Carlo test (999 times). Results of this study extended the existing molecular tools for studying the NC10 bacterial community structures and provided new information on the ecological distributions of NC10 bacteria.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jes.2017.04.016DOI Listing
March 2018

Dynamics of Heterotrophic Bacterial Assemblages within Synechococcus Cultures.

Appl Environ Microbiol 2018 02 17;84(3). Epub 2018 Jan 17.

State Key Laboratory for Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, People's Republic of China

Interactions between photoautotrophic and heterotrophic microorganisms are central to the marine microbial ecosystem. Lab cultures of one of the dominant marine photoautotrophs, , have historically been difficult to render axenic, presumably because these bacteria depend upon other organisms to grow under these conditions. These tight associations between and heterotrophic bacteria represent a good relevant system to study interspecies interactions. Ten individual strains, isolated from eutrophic and oligotrophic waters, were chosen for investigation. Four to six dominant associated heterotrophic bacteria were detected in the liquid cultures of each isolate, comprising members of the -- (CFB) group (mainly from and ), (mainly from the clade), (mainly from the and ), and The presence of the CFB group, , and showed clear geographic patterns related to the isolation environments of the bacteria. An investigation of the population dynamics within a growing culture (XM-24) of one of the isolates, including an evaluation of the proportions of cells that were free-living versus aggregated/attached, revealed interesting patterns for different bacterial groups. In sp. strain XM-24 culture, flavobacteria, which was the most abundant group throughout the culture period, tended to be aggregated or attached to the cells, whereas the actinobacteria demonstrated a free-living lifestyle, and roseobacters displayed different patterns depending on the culture growth phase. Factors contributing to these succession patterns for the heterotrophs likely include interactions among the culture community members, their relative abilities to utilize different compounds produced by cells and changes in the compounds released as culture growth proceeds, and their responses to other changes in the environmental conditions throughout the culture period. Marine microbes exist within an interactive ecological network, and studying their interactions is an important part of understanding their roles in global biogeochemical cycling and the determinants of microbial diversity. In this study, the dynamic relationships between spp. and their associated heterotrophic bacteria were investigated. -associated heterotrophic bacteria had similar geographic distribution patterns as their "host" and displayed different lifestyles (free-living versus attached/aggregated) according to the culture growth phases. Combined organic carbon composition and bacterial lifestyle data indicated a potential for succession in carbon utilization patterns by the dominant associated heterotrophic bacteria. Comprehending the interactions between photoautotrophs and heterotrophs and the patterns of organic carbon excretion and utilization is critical to understanding their roles in oceanic biogeochemical cycling.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.01517-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5772231PMC
February 2018

Fugitive halocarbon emissions from working face of municipal solid waste landfills in China.

Waste Manag 2017 Dec 13;70:149-157. Epub 2017 Sep 13.

School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China. Electronic address:

Halocarbons are important anthropogenic greenhouse gases (GHGs) due to their long lifetime and large characteristic factors. The present study for the first time assessed the global warming potential (GWP) of fugitive halocarbon emissions from the working face of landfills in China. The national emissions of five major halocarbons (CFC-11, CFC-113, CHCl, CHCl and CCl) from the working face of municipal solid waste landfills in China were provided through observation-based estimations. The fluxes of halocarbons from working face of landfills were observed much higher than covered cells in landfills hence representing the hot spots of landfill emissions. The annual emissions of the halocarbons from landfills in China were 0.02-15.6kt·y, and their GWPs were 128-60,948kt-CO-eq·y based on their characteristic factors on a 100-year horizon. CFC-113 was the dominant species owing to its highest releasing rate (i.e. 15.4±19.1g·t) and largest characteristic factor, resulting in a GWP up to 4036±4855kt-CO-eq·y. The annual emissions of CFC-113 from landfills (i.e. 0.61kt·y) made up ∼76% of the total national CFC-113 emissions. The GWPs of halocarbons were estimated ∼14.4% of landfill methane emissions. Therefore, fugitive halocarbons emissions from working face are significant sources of GHGs in landfill sites in China, although they comprise a small fraction of total landfill gases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wasman.2017.08.042DOI Listing
December 2017

Expression and clinical significance of CD147 in renal cell carcinoma: a meta-analysis.

Oncotarget 2017 Aug 10;8(31):51331-51344. Epub 2017 Apr 10.

Xiangya School of Medicine, Central South University, Changsha, China.

Objective: To assess clinical significance of CD147 in renal cell carcinoma.

Methods: Collect case-control studies which focus on CD147's expression in renal cell carcinoma. Trails were retrieved from CBM, CNKI, Wan-fang database, PubMed, Cochrane Library and Embase. According to the inclusion and exclusion criteria, data extraction and quality assessment were done by two researchers independently, and outcomes were pooled with Revman5.3 and STATA14.0.

Results: A total of 11 studies were confirmed, among which renal cell carcinoma 887 cases, non-cancer 505cases. As for the positive rate of CD147, there are statistical differences among survival, renal cell carcinoma tissue vs. non-cancer tissues [OR= 8.19, P= 0.0002], with vs. without lymph node metastases [OR= 6.52, P= 0.001], clinical stage III~IV vs. II~I [OR= 4.07, P< 0.00001], histopathological stage III~IV vs. II [OR= 3.01, P= 0.002], histopathological stage III~IV vs. I [OR= 7.50, P< 0.00001], tumor size [OR= 5.01, P= 0.0007]. No significant difference was tested among different age, gender, histological types and Position of cancer.

Conclusion: As shown in our results, CD 147 may participate the whole course of carcinogenesis of renal cell carcinoma, which might be valuable for the diagnosis, treatment and prognosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.17376DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5584252PMC
August 2017

Synthesis of renewable high-density fuel with isophorone.

Sci Rep 2017 07 21;7(1):6111. Epub 2017 Jul 21.

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, No. 457 Zhongshan Road, Dalian 116023, No. 457 Zhongshan Road, Dalian, 116023, China.

1,1,3-Trimethyl-5-(2,4,4-trimethylcyclohexyl)cyclohexane, a renewable high density fuel, was first produced in a high overall carbon yield (~70%) with isophorone which can be derived from hemicellulose. The synthetic route used this work contains three steps. In the first step, 3,3,5-trimethylcyclohexanone was synthesized by the selective hydrogenation of isophorone. Among the investigated catalysts, the Pd/C exhibited the highest activity and selectivity. Over this catalyst, a high carbon yield (99.0%) of 3,3,5-trimethylcyclohexanone was achieved under mild conditions (298 K, 2 MPa H, 1 h). In the second step, 3,5,5-trimethyl-2-(3,3,5-trimethylcyclohexylidene)cyclohexanone was produced in a high carbon yield (76.4%) by the NaOH catalyzed self-aldol condensation of 3,3,5-trimethylcyclohexanone which was carried out in a round bottom flask attached to the Dean-Stark apparatus. In the third step, the 3,5,5-trimethyl-2-(3,3,5-trimethylcyclohexylidene)cyclohexanone was hydrodeoxygenated under solvent-free conditions. High carbon yield (93.4%) of 1,1,3-trimethyl-5-(2,4,4-trimethylcyclohexyl)cyclohexane was obtained over the Ni/SiO catalyst. The 1,1,3-trimethyl-5-(2,4,4-trimethylcyclohexyl)cyclohexane as obtained has a density of 0.858 g mL and a freezing point of 222.2 K. As a potential application, it can be blended into conventional fuels (such as RP-1, RG-1, etc.) for rocket propulsion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-017-06556-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5522473PMC
July 2017

Genomic profiling of long non-coding RNA and mRNA expression associated with acquired temozolomide resistance in glioblastoma cells.

Int J Oncol 2017 Aug 7;51(2):445-455. Epub 2017 Jun 7.

The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China.

Temozolomide (TMZ) is an alkylating chemotherapeutic agent widely used in anti-glioma treatment. However, acquired TMZ resistance represents a major clinical challenge that leads to tumor relapse or progress. This study investigated the genomic profiles including long non-coding RNA (lncRNA) and mRNA expression associated with acquired TMZ resistance in glioblastoma (GBM) cells in vitro. The TMZ-resistant (TR) of GBM sub-cell lines were established through repetitive exposure to increasing TMZ concentrations in vitro. The differentially expressed lncRNAs and mRNAs between the parental U87 and U87TR cells were detected by human lncRNA microarray method. In this study, we identified 2,692 distinct lncRNAs demonstrating >2-fold differential expression with 1,383 lncRNAs upregulated and 1,309 lncRNAs downregulated. Moreover, 4,886 differential mRNAs displayed 2,933 mRNAs upregulated and 1,953 mRNAs downregulated. Further lncRNA classification and subgroup analysis revealed the potential functions of the lncRNA-mRNA relationship associated with the acquired TMZ resistance. Gene ontology and pathway analysis on mRNAs showed significant biological regulatory genes and pathways involved in acquired TMZ resistance. Moreover, we found the ECM‑receptor interaction pathway was significantly downregulated and ECM related collagen Ι, fibronectin, laminin and CD44 were closely associated with the TR phenotype in vitro. Our findings indicate that the dysregulated lncRNAs and mRNAs identified in this work may provide novel targets for overcoming acquired TMZ resistance in GBM chemotherapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/ijo.2017.4033DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5505000PMC
August 2017

CD147 and glioma: a meta-analysis.

J Neurooncol 2017 Aug 30;134(1):145-156. Epub 2017 May 30.

Xiangya School of Medicine, Central South University, Changsha, China.

Gliomas are the most common primary brain tumors. This meta-analysis aimed to systematically evaluate the relationship between CD147 expression in tissues and the clinicopathological features of patients with glioma. We searched PubMed (1966-2016), EMBASE (1980-2016), Cochrane Library (1996-2016), Web of Science (1945-2016), China National Knowledge Infrastructure (1982-2016), and Wan Fang databases (1988-2016). Quality assessment of the literature was performed using the Newcastle-Ottawa Scale, with Revman 5.3 and Stata 14.0 for analysis. In total, 1806 glioma patients from 19 studies were included, and patients with CD147 overexpression had poorer overall survival [hazard ratio (HR) = 2.211, P < 0.0001], a higher risk of recurrence (HR = 2.20, P = 0.0025), and a lower 5-year survival rate [odds ratio (OR) 0.12; 95% CI 0.08-0.19; P < 0.00001]. We observed significant differences in CD147 expression when comparing glioma tissues versus non-cancerous brain tissues (OR 20.42; 95% CI 13.94-29.91; P < 0.00001), tumor grades III-IV versus grades I-II (OR 5.88, 95% CI 4.15-8.34; P < 0.00001), and large versus small tumors (OR 1.58, 95% CI 1.04-2.40; P = 0.03). We also observed a significant correlation with matrix metalloproteinase (MMP) 2 (OR 39.11, 95% CI 11.47-133.34; P < 0.00001) and MMP9 (OR 13.35, 95% CI 4.67-38.18; P < 0.00001). CD147 expression did not differ based on patient's age (young vs. old, P = 0.89) or gender (female vs. male, P = 0.57). CD147 expression may be a potential prognostic biomarker for poorer overall and relapse-free survival, and may affect the 5-year survival rate in glioma patients. CD147 expression is also closely correlated with poor clinical characteristics in glioma patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11060-017-2499-4DOI Listing
August 2017

Hybrid 3D printing and electrodeposition approach for controllable 3D alginate hydrogel formation.

Biofabrication 2017 Jun 7;9(2):025032. Epub 2017 Jun 7.

Department of Mechanical Engineering, Xi'an University of Science and Technology, Xi'an, People's Republic of China.

Calcium alginate hydrogels are widely used as biocompatible materials in a substantial number of biomedical applications. This paper reports on a hybrid 3D printing and electrodeposition approach for forming 3D calcium alginate hydrogels in a controllable manner. Firstly, a specific 3D hydrogel printing system is developed by integrating a customized ejection syringe with a conventional 3D printer. Then, a mixed solution of sodium alginate and CaCO nanoparticles is filled into the syringe and can be continuously ejected out of the syringe nozzle onto a conductive substrate. When applying a DC voltage (∼5 V) between the substrate (anode) and the nozzle (cathode), the Ca released from the CaCO particles can crosslink the alginate to form calcium alginate hydrogel on the substrate. To elucidate the gel formation mechanism and better control the gel growth, we can further establish and verify a gel growth model by considering several key parameters, i.e., applied voltage and deposition time. The experimental results indicate that the alginate hydrogel of various 3D structures can be formed by controlling the movement of the 3D printer. A cell viability test is conducted and shows that the encapsulated cells in the gel can maintain a high survival rate (∼99% right after gel formation). This research establishes a reliable method for the controllable formation of 3D calcium alginate hydrogel, exhibiting great potential for use in basic biology and applied biomedical engineering.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/1758-5090/aa6ed8DOI Listing
June 2017

Screening for potential genes associated with bone overgrowth after mid-shaft femur fracture in a rat model.

J Orthop Surg Res 2017 Jan 17;12(1). Epub 2017 Jan 17.

The Six Affiliated Hospital of Xinjiang Medical University Medical Examination Center, Autonomous Region, Five Star South Road, No. 39, Urumqi City, Xinjiang Uygur, 830002, China.

Background: We investigated the underlying molecular mechanisms of bone overgrowth after femoral fracture by using high-throughput bioinformatics approaches.

Methods: The gene expression profile of GSE3298 (accession number) was obtained from the Gene Expression Omnibus database. Sixteen femoral growth plate samples, including nine samples without fracture and seven fracture samples for seven time points, were used for analysis. The Limma package was applied to identify differentially expressed genes (DEGs) between fractured and intact samples. The DAVID online tool was used for Gene ontology functional and pathway enrichment analysis. A protein-protein interaction (PPI) network established by String software was used to identify interactions between significant DEGs, and network modules were detected using plug-in MCODE. Additionally, a transcription regulatory network was constructed based on the ENCODE Project and PPI network.

Results: A total of 680 DEGs were screened in fractured femoral growth plate samples compared with controls, including 238 up- and 442 down-regulated genes. These DEGs were significantly involved in the calcium signaling pathway and cancer pathway. A PPI network was constructed with 167 nodes and 233 edges, and module analysis demonstrated that CCL2, CSF2, NOS2, and DLC1 may stimulate bone overgrowth after femoral fracture via anti-apoptosis-related functions. A transcription regulatory network was constructed with 387 interacting pairs, and overlapping nodes were significantly enriched in intracellular signaling cascade and regulation of cell proliferation, among others.

Conclusions: Bone overgrowth was associated with changes in the expression of identified DEGs such as CCL2, NOS2, CSF2, and DLC1 in the femoral head. They may be important in regulating bone overgrowth via the anti-apoptosis of osteoblasts.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13018-017-0510-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5240322PMC
January 2017

Genome Sequence of Salegentibacter salarius KCTC 12974, Isolated from a Marine Solar Saltern of the Yellow Sea in South Korea.

Genome Announc 2016 Nov 23;4(6). Epub 2016 Nov 23.

State Key Laboratory of Marine Environmental Sciences, Xiamen University, Xiamen, Fujian, China.

Salegentibacter salarius KCTC 12974 is isolated from a marine solar saltern of the Yellow Sea in South Korea. Here, we report the draft genome sequence of Salegentibacter salarius KCTC 12974. Various glycoside hydrolase genes in even numbers in the genome reflect the ecological adaption of KCTC 12974 to its habitat.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/genomeA.01308-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5122682PMC
November 2016

Downregulation of Bmi-1 suppresses epithelial‑mesenchymal transition in melanoma.

Oncol Rep 2017 Jan 15;37(1):139-146. Epub 2016 Nov 15.

Department of Dermatology, Northwest Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China.

Epithelial-mesenchymal transition (EMT) contributes to the invasion and metastasis of numerous malignant cancers, including melanoma. A significant higher expression of B-lymphoma Moloney murine leukemia virus insertion region-1 (Bmi-1) has been reported in cell lines from metastatic melanoma compared to cell lines from primary melanoma. There are studies that show that knockdown of Bmi-1 could induce E-cadherin expression in melanoma cells. However, the role of Bmi-1 in mediating EMT-like changes in melanoma has not yet been fully studied. In the present study, knockdown of Bmi-1 by shRNA transduction decreased the invasion properties of the cultured human melanoma cells A375 by a Matrigel invasion assay, along with alterations in EMT-related markers E-cadherin, α-catenin, vimentin and N-cadherin. The aforementioned altered expression of EMT markers was verified in BALB/c-nude mouse xenografts. Furthermore, to explore the underlying regulatory mechanism of EMT, we detected the significant downregulation of p-Akt/p‑NF-κB/MMP-2 and the upregulation of PTEN in Bmi-1-silenced A375 cells. The present study demonstrated that knockdown of Bmi-1 significantly inhibited the aggressive behavior of melanoma by reversing EMT-like changes via the PTEN/p-Akt/p‑NF-κB/MMP-2 pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/or.2016.5244DOI Listing
January 2017

Geographic Impact on Genomic Divergence as Revealed by Comparison of Nine Citromicrobial Genomes.

Appl Environ Microbiol 2016 12 21;82(24):7205-7216. Epub 2016 Nov 21.

State Key Laboratory for Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, People's Republic of China

Aerobic anoxygenic phototrophic bacteria (AAPB) are thought to be important players in oceanic carbon and energy cycling in the euphotic zone of the ocean. The genus Citromicrobium, widely found in oligotrophic oceans, is a member of marine alphaproteobacterial AAPB. Nine Citromicrobium strains isolated from the South China Sea, the Mediterranean Sea, or the tropical South Atlantic Ocean were found to harbor identical 16S rRNA sequences. The sequencing of their genomes revealed high synteny in major regions. Nine genetic islands (GIs) involved mainly in type IV secretion systems, flagellar biosynthesis, prophage, and integrative conjugative elements, were identified by a fine-scale comparative genomics analysis. These GIs played significant roles in genomic evolution and divergence. Interestingly, the coexistence of two different photosynthetic gene clusters (PGCs) was not only found in the analyzed genomes but also confirmed, for the first time, to our knowledge, in environmental samples. The prevalence of the coexistence of two different PGCs may suggest an adaptation mechanism for Citromicrobium members to survive in the oceans. Comparison of genomic characteristics (e.g., GIs, average nucleotide identity [ANI], single-nucleotide polymorphisms [SNPs], and phylogeny) revealed that strains within a marine region shared a similar evolutionary history that was distinct from that of strains isolated from other regions (South China Sea versus Mediterranean Sea). Geographic differences are partly responsible for driving the observed genomic divergences and allow microbes to evolve through local adaptation. Three Citromicrobium strains isolated from the Mediterranean Sea diverged millions of years ago from other strains and evolved into a novel group.

Importance: Aerobic anoxygenic phototrophic bacteria are a widespread functional group in the upper ocean, and their abundance could be up to 15% of the total heterotrophic bacteria. To date, a great number of studies display AAPB biogeographic distribution patterns in the ocean; however, little is understood about the geographic isolation impact on the genome divergence of marine AAPB. In this study, we compare nine Citromicrobium genomes of strains that have identical 16S rRNA sequences but different ocean origins. Our results reveal that strains isolated from the same marine region share a similar evolutionary history that is distinct from that of strains isolated from other regions. These Citromicrobium strains diverged millions of years ago. In addition, the coexistence of two different PGCs is prevalent in the analyzed genomes and in environmental samples.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.02495-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5118931PMC
December 2016

Health risk impacts analysis of fugitive aromatic compounds emissions from the working face of a municipal solid waste landfill in China.

Environ Int 2016 Dec 19;97:15-27. Epub 2016 Oct 19.

School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China.

Aromatic compounds (ACs) emitted from landfills have attracted a lot of attention of the public due to their adverse impacts on the environment and human health. This study assessed the health risk impacts of the fugitive ACs emitted from the working face of a municipal solid waste (MSW) landfill in China. The emission data was acquired by long-term in-situ samplings using a modified wind tunnel system. The uncertainty of aromatic emissions is determined by means of statistics and the emission factors were thus developed. Two scenarios, i.e. 'normal-case' and 'worst-case', were presented to evaluate the potential health risk in different weather conditions. For this typical large anaerobic landfill, toluene was the dominant species owing to its highest releasing rate (3.40±3.79g·m·d). Despite being of negligible non-carcinogenic risk, the ACs might bring carcinogenic risks to human in the nearby area. Ethylbenzene was the major health threat substance. The cumulative carcinogenic risk impact area is as far as ~1.5km at downwind direction for the normal-case scenario, and even nearly 4km for the worst-case scenario. Health risks of fugitive ACs emissions from active landfills should be concerned, especially for landfills which still receiving mixed MSW.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envint.2016.10.010DOI Listing
December 2016

Structure and diversity of bacterial communities in two large sanitary landfills in China as revealed by high-throughput sequencing (MiSeq).

Waste Manag 2017 May 8;63:41-48. Epub 2016 Aug 8.

School of Environment, Tsinghua University, Beijing 100084, China; Key Laboratory for Solid Waste Management and Environment Safety (Tsinghua University), Ministry of Education of China, Tsinghua University, Beijing 100084, China. Electronic address:

Landfill disposal has been considered as a very economically viable management practice for municipal solid waste in mainland China. However, insufficient knowledge of the bacterial community structure and diversity in landfills hampers effectively landfill disposal. In this study, the structure and diversity of bacterial communities in two large sanitary landfills in northern and western parts of China were examined by high-throughput sequencing via a MiSeq platform. Nearly 1million effective sequences (981,575) were obtained from the 20 samples collected from four independent sites with different deposit depths (up to 18m). These sequences contained high amount of operational taxonomic units (OTUs), 2511-9955 OTUs at a cutoff level of 3% and a sequencing depth of 23,928. Firmicutes, Bacteroidetes and Proteobacteria were the most abundant phyla in the samples. Clear geographical differences between the sampling sites were revealed by nonmetric multidimensional scaling. Most of the samples from the same sampling site could be clustered together. Thus, the heterogeneity of the bacterial community structures was more significantly affected by the sampling site than by sampling depth. Redundancy analysis results suggested that seven physicochemical attributes, namely NH-N, NO-N, moisture, pH, dissolved organic carbon (DOC), SO and total Cu element, significantly affected the bacterial community structures (P<0.001) based on variance inflation factor selection. Among these attributes, NH-N, NO-N, moisture, pH and DOC were the most important parameters influencing the bacterial community structures (P<0.05). This study elucidated the structure and diversity of bacterial communities in landfills and discerned the relationships between bacterial community structures and physicochemical attributes. To the best of our knowledge, this study is among the first to characterize bacterial community structures in landfills by using this novel high-throughput sequencing approach.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wasman.2016.07.047DOI Listing
May 2017

A Comparison of 14 Erythrobacter Genomes Provides Insights into the Genomic Divergence and Scattered Distribution of Phototrophs.

Front Microbiol 2016 24;7:984. Epub 2016 Jun 24.

State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University Xiamen, China.

Aerobic anoxygenic phototrophic bacteria (AAPB) are bacteriochlorophyll a (Bchl a)-containing microbial functional population. Erythrobacter is the first genus that was identified to contain AAPB species. Here, we compared 14 Erythrobacter genomes: seven phototrophic strains and seven non- phototrophic strains. Interestingly, AAPB strains are scattered in this genus based on their phylogenetic relationships. All 14 strains could be clustered into three groups based on phylo-genomic analysis, average genomic nucleotide identity and the phylogeny of signature genes (16S rRNA and virB4 genes). The AAPB strains were distributed in three groups, and gain and loss of phototrophic genes co-occurred in the evolutionary history of the genus Erythrobacter. The organization and structure of photosynthesis gene clusters (PGCs) in seven AAPB genomes displayed high synteny of major regions except for few insertions. The 14 Erythrobacter genomes had a large range of genome sizes, from 2.72 to 3.60 M, and the sizes of the core and pan- genomes were 1231 and 8170 orthologous clusters, respectively. Integrative and conjugative elements (ICEs) were frequently identified in genomes we studied, which might play significant roles in shaping or contributing to the pan-genome of Erythrobacter. Our findings suggest the ongoing evolutionary divergence of Erythrobacter genomes and the scattered distribution characteristic of PGC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2016.00984DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4919336PMC
July 2016

A Retrospective Study on the Characteristics of Treating Nevus of Ota by 1064-nm Q-switched Neodymium-doped Yttrium Aluminum Garnet Laser.

Indian J Dermatol 2016 May-Jun;61(3):347

Department of Dermatology, Northwest Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, PR China.

Background: The Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser has a significant effect in treating nevus of Ota, but there is lack of a retrospective study about the characteristics of efficacy.

Aims And Objectives: To retrospectively analyze the correlation between the clinical characteristics and efficacy, complications, recurrence of QS Nd:YAG laser in treating nevus of Ota.

Materials And Methods: One hundred and seventy-one Chinese patients (144 female, 27 male) of nevus of Ota were treated with the 1064-nm QS Nd:YAG laser. All cases were treated with fluencies of 4-8 J/cm(2) and a spot size of 2-4 mm. Clinical photographs were taken before every treatment and patients were followed up by their clinicians.

Results: One hundred and forty-five patients (84.8%) acquired more than 75% improvement with an average of 4.6 sessions. The treatment effect has no significant correlation with sex (P > 0.05). The blue-black and brown lesions improved more than the light-brown (P < 0.05). Hyperpigmentation affected two (1.2%) of the patients and hypopigmentation affected one patient (0.6%). No other adverse effect was observed. Recurrence was seen in two patients (1.2%).

Conclusion: The 1064-nm QS Nd:YAG laser is effective with rare complications and recurrence in the treatment of nevus of Ota. The efficacy correlated with lesion color, which is meaningful to estimate the prognosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/0019-5154.182470DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4885205PMC
June 2016

Long noncoding RNA RP11-838N2.4 enhances the cytotoxic effects of temozolomide by inhibiting the functions of miR-10a in glioblastoma cell lines.

Oncotarget 2016 Jul;7(28):43835-43851

The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China.

Resistance to temolozomide (TMZ), the standard chemotherapy agent for treating glioblastomas (GBM), is a major clinical problem for patients with GBM. Recently, long noncoding RNAs (lncRNAs) have been implicated in chemotherapy resistance in various cancers. In this study, we found that the level of the lncRNA RP11-838N2.4 was lower in TMZ-resistant GBM cells (U87TR, U251TR) compared to the parental, non-resistant GBM cells (U87, U251). In GBM patients, the decreased level of lncRNA RP11-838N2.4 correlated with higher risk of GBM relapse, as well as shorter postoperative survival times. We further found that lncRNA RP11-838N2.4 could enhances the cytotoxic effects of temozolomide to GBM cells both in vivo and in vitro. Moreover, lncRNA RP11-838N2.4 acts as an endogenous sponge, suppressing the function of miR-10a through conserved sequences and increasing the expression of EphA8 that enhanced the rate of cell apoptosis, thereby intensified sensitivity of GBM cells to TMZ. Additionally, lncRNA RP11-838N2.4 inhibited the activity of transforming growth factor-β (TGF-β) independent of miR-10a. Finally, Characterization of lncRNA RP11-838N2.4 could contribute to strategies for enhancing the efficacy of TMZ.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.9699DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5190063PMC
July 2016

Melkersson-Rosenthal Syndrome with Genitalia Involved in a 12-Year-Old Boy.

Ann Dermatol 2016 Apr 31;28(2):232-6. Epub 2016 Mar 31.

Department of Dermatology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.

Melkersson-Rosenthal syndrome (MRS) is an uncommon granulomatous disease characterized by the triad of relapsing facial paralysis, orofacial swelling, and fissured tongue. Genital swelling in MRS is rarely reported. We presented the first case of complete MRS with genital swelling in a child. Biopsy examinations of both the child's lower lip and penis showed noncaseating granuloma and intralymphatic granuloma infiltration. No symptoms or signs of other systemic disease (Crohn's disease or sarcoidosis) were observed after 2 years of follow-up. Genetic screening for CARD15/NOD2 in this patient showed negative, which further confirmed the diagnosis of MRS. Eleven other cases of suspected complete or incomplete MRS with genitalia involved were reviewed. Our case emphasizes the specific clinical feature of MRS with genitalia involved, which was genetically different from Crohn's disease and could be an independent entity. Lymphatic obstruction is responsible for localized edema in MRS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5021/ad.2016.28.2.232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4828388PMC
April 2016

Assessment of Left Ventricular Dissipative Energy Loss by Vector Flow Mapping in Patients With End-Stage Renal Disease.

J Ultrasound Med 2016 May 1;35(5):965-73. Epub 2016 Apr 1.

Department of Cardiology, West China Hospital of Sichuan University, Chengdu, China.

Objectives: Dissipative energy loss derived from vector flow mapping represents the viscous dissipation of turbulent blood flow. We aimed to determine the left ventricular (LV) energy loss in patients with end-stage renal disease (ESRD).

Methods: Patients with ESRD and a preserved LV ejection fraction, who consisted of a group receiving peritoneal dialysis, a group receiving hemodialysis, and a group receiving preparation for dialysis initiation, were examined by echocardiography; a group of healthy control participants were examined as well. Vector flow mapping analysis was then performed from the apical 4-chamber view to calculate the energy loss during diastole and systole in the left ventricle.

Results: Conventional transthoracic echocardiography and LV energy loss calculations were successfully performed in 63 cases and 50 controls. The patients with ESRD had significantly higher diastolic energy loss [median (interquartile range), 71.73 (46.08-106.75) versus 23.32 (17.17-29.26) mW/m; P < .001] and higher systolic energy loss [25.28 (19.03-33.93) versus 12.52 (9.35-16.47) mW/m; P < .001]. A significant difference in diastolic energy loss between the peritoneal dialysis and preparation groups was found [54.92 (39.28-89.94) versus 84.82 (62.58-171.4) mW/m; P = .04]. In patients with ESRD, the log-transformed diastolic energy loss had a significant association with the peak early diastolic transmitral flow velocity (P = .011), peak early diastolic transmitral flow velocity-to-peak early diastolic mitral annular flow velocity ratio (P = .001), LV mass index (P = .017), and heart rate (P = .003).

Conclusions: Impaired blood flow efficiency was detected in patients with ESRD by using dissipative energy loss derived from vector flow mapping. The energy loss value could be a novel parameter for evaluating the ventricular workload of uremic hearts in terms of fluid mechanics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7863/ultra.15.06009DOI Listing
May 2016

Molybdenum carbide as an efficient catalyst for low-temperature hydrogenation of dimethyl oxalate.

Chem Commun (Camb) 2016 Apr 17;52(28):5030-2. Epub 2016 Mar 17.

State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China.

Silica-supported molybdenum carbide (Mo2C/SiO2) is found to be a highly active, selective and stable catalyst for the hydrogenation of dimethyl oxalate to ethanol at low temperatures (473 K). Moreover, the formation of ethanol over the Mo2C catalyst performs via the novel intermediate methyl acetate instead of ethylene glycol forming over the Cu catalyst.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c6cc01709fDOI Listing
April 2016

Genome sequence of Bacillus sp. CHD6a, isolated from the shallow-sea hydrothermal vent.

Mar Genomics 2016 Feb 24;25:15-16. Epub 2015 Oct 24.

State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China. Electronic address:

Bacillus sp. CHD6a, which can produce oval endosperms, isolated from the shallow-sea hydrothermal vent systems off northeast Taiwan's coast. Here, we report the draft genome sequence of Bacillus sp. CHD6a. It comprises ~3.97 Mb in 55 contigs with the G+C content of 39.9%, and a total of 3740 protein-coding genes were obtained.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.margen.2015.10.007DOI Listing
February 2016

Hypertrophic Lichenoid Eruption in a Child Successfully Treated Using Acitretin and Surgery: A Case Report and Literature Review.

Pediatr Dermatol 2015 Nov-Dec;32(6):e238-41. Epub 2015 Jul 29.

Department of Dermatology, Northwest Hospital, Xi'an Jiaotong University, Xi'an Shaanxi, China.

A 9-year-old boy presented with a history of keratotic violaceous plaques on the limbs and face for 8 years that had gradually progressed to erosive nodules on the extremities for 2 years. Several biopsies revealed hyperkeratosis, liquefactive degeneration of the basal layer, and a bandlike predominantly lymphocytic infiltrate. Based on the clinical and histologic findings, the patient was diagnosed with keratosis lichenoides chronica, a rare chronic dermatosis that is particularly uncommon in childhood. There are fewer than 20 reported cases of pediatric-onset keratosis lichenoides chronica in the current literature, with occurrence of pseudoepitheliomatous hyperplasia of primary keratosis lichenoides chronica lesions being even rarer. Here we present a unique pediatric-onset case accompanied by pseudoepitheliomatous hyperplasia that posed a significant treatment challenge to dermatologists. Significant improvement in the pseudoepitheliomatous skin lesions was achieved after treatment with oral acitretin capsules and surgical excision with skin grafting.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/pde.12658DOI Listing
September 2016

MiR-203 downregulation is responsible for chemoresistance in human glioblastoma by promoting epithelial-mesenchymal transition via SNAI2.

Oncotarget 2015 Apr;6(11):8914-28

Department of Neurosurgery, Neurosurgery Institute of Guangdong, Key Laboratory on Brain Function Repair and Regeneration of Guangdong, Zhujiang Hospital, Southern Medical University, Guangzhou, China.

Epithelial-mesenchymal transition (EMT) has been recognized as a key element of cell migration, invasion, and drug resistance in several types of cancer. In this study, our aim was to clarify microRNAs (miRNAs)-related mechanisms underlying EMT followed by acquired resistance to chemotherapy in glioblastoma (GBM). We used multiple methods to achieve our goal including microarray analysis, qRT-PCR, western blotting analysis, loss/gain-of-function analysis, luciferase assays, drug sensitivity assays, wound-healing assay and invasion assay. We found that miR-203 expression was significantly lower in imatinib-resistant GBM cells (U251AR, U87AR) that underwent EMT than in their parental cells (U251, U87). Ectopic expression of miR-203 with miRNA mimics effectively reversed EMT in U251AR and U87AR cells, and sensitized them to chemotherapy, whereas inhibition of miR-203 in the sensitive lines with antisense oligonucleotides induced EMT and conferred chemoresistance. SNAI2 was identified as a direct target gene of miR-203. The knockdown of SNAI2 by short hairpin RNA (shRNA) inhibited EMT and drug resistance. In GBM patients, miR-203 expression was inversely related to SNAI2 expression, and those tumors with low expression of miR-203 experienced poorer clinical outcomes. Our findings indicate that re-expression of miR-203 or targeting SNAI2 might serve as potential therapeutic approaches to overcome chemotherapy resistance in GBM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4496192PMC
http://dx.doi.org/10.18632/oncotarget.3563DOI Listing
April 2015

Pyrosequencing analysis of aerobic anoxygenic phototrophic bacterial community structure in the oligotrophic western Pacific Ocean.

FEMS Microbiol Lett 2015 Apr 26;362(8):fnv034. Epub 2015 Feb 26.

State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China

Aerobic anoxygenic phototrophic bacteria (AAPB) represent a widespread functional bacterial group defined by their obligate aerobic and facultative photoheterotrophic abilities. They are an active part of the marine microbial community as revealed by a large number of previous investigations. Here, we made an in-depth comparison of AAPB community structures in the subsurface water and the upper twilight zone of the western Pacific Ocean using high-throughput sequencing based on the pufM gene. Approximately, 100 000 sequences, grouped into 159 OTUs (94% cut-off value), included 44 and 24 OTUs unique to the subsurface and the upper twilight zone, respectively; 92 OTUs were common to both subsurface and twilight zone, and 3 OTUs were found in all samples. Consistent with previous studies, AAPB belonging to the Gammaproteobacteria were the dominant group in the whole water column, followed by the alphaproteobacterial AAPB. Comparing the relative abundance distribution patterns of different clades, an obvious community-structure separation according to deeper or shallower environment could be observed. Sulfitobacter-like, Loktanella-like, Erythrobacter-like, Dinoroseobacter-like and Gamma-HIMB55-like AAPB preferred the high-light subsurface water, while Methylobacterium-like, 'Citromicrobium'-like, Roseovarius-like and Bradyrhizobium-like AAPB, the dim light environment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/femsle/fnv034DOI Listing
April 2015

Genome sequence of aerobic anoxygenic phototrophic bacterium Erythrobacter sp. JL475, isolated from the South China Sea.

Mar Genomics 2015 Jun 17;21:15-6. Epub 2015 Feb 17.

State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China. Electronic address:

Erythrobacter sp. JL475 is a bacteriochlorophyll a-containing aerobic anoxygenic photo-heterotrophic bacterium. Here, we report the draft genome sequence of Erythrobacter sp. JL475 isolated from the South China Sea. It comprises ~3.26Mbp in 7 contigs with the G+C content of 61.7%. A total of 3042 protein-coding genes were obtained, and one complete photosynthetic gene cluster (~38Kbp) was found.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.margen.2015.02.006DOI Listing
June 2015

[email protected] core-shell nanocubes: epitaxial growth synthesis and surface-enhanced Raman scattering performance.

Phys Chem Chem Phys 2015 Mar;17(10):6819-26

Institute of Photonics, Faculty of Science, Ningbo University, Ningbo 31 5211, Zhejiang, China.

Novel [email protected] core-shell nanocubes (NCs) were successfully prepared by the controlled epitaxial growth of Ag shells onto Au nanoellipsoids (NEs) in the presence of surfactants. The growth mechanism of the [email protected] core-shell NCs was systematically investigated by analyzing their morphology, optical properties, and crystallography. The localized surface plasmon resonance (LSPR) characteristics and the electric field distribution of the [email protected] core-shell NCs were studied using the finite element method (FEM) based on the plasmon hybridization theory. Compared with pure Ag NCs, the absorption spectrum of the [email protected] core-shell NCs exhibits a red shift and a weak shoulder near 550 nm, and the notable enhancement of electric field occurs around the corners along the long-axis of the Au ellipsoidal core because of plasmonic resonant coupling. Surface-enhanced Raman scattering (SERS) of the [email protected] core-shell NCs labeled with 4-mercaptobenzoic acid molecules reveals that the bimetallic core-shell NCs possess efficient SERS activity with an enhancement factor EF = 2.27 × 10(6), thus confirming the possibility of using the [email protected] core-shell NCs as a stable probe for SERS-based biosensing applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c4cp05642fDOI Listing
March 2015

Polymerase I and transcript release factor acts as an essential modulator of glioblastoma chemoresistance.

PLoS One 2014 18;9(4):e93439. Epub 2014 Apr 18.

The National Key Clinic Specialty, the Neurosurgery Institute of Guangdong Province, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, P. R. China.

Objectives: This study is to investigate if polymerase I and transcript release factor (PTRF) acts as a modulator in glioblastoma (GBM) chemoresistance.

Methods: Multidrug resistant (MDR) GBM cell line U251AR was established by exposing the U251 cell line to imatinib. The 2D-DIGE and MALDI-TOF/TOF-MS were performed on U251 and U251AR cell lines to screen MDR-related proteins. The expression of PTRF was determined by Western blot and quantitative RT-PCR analyses.

Results: When compared with the parental U251 cells, expression of 21 proteins was significantly altered in U251AR cells. Among the 21 differentially expressed proteins, the expression of PTRF was up-regulated by 2.14 folds in U251AR cells when compared with that in the parental U251 cells. Knockdown of PTRF in GBM cell lines significantly increased chemosensitivity of cells to various chemical drugs and decreased the expression levels of caveolin1, a major structural component of caveolae. Expression levels of PTRF and caveolin1 were significantly up-regulated in the relapsed GBM patients. The mRNA level of PTRF and caveolin1 showed a positive correlation in the same GBM specimens.

Conclusions: Our results indicate that PTRF acts as a modulator in GBM chemoresistance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0093439PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3991573PMC
January 2015
-->