| 1. |
- Shu, Xiang, et al.
(författare)
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Large-scale Integrated Analysis of Genetics and Metabolomic Data Reveals Potential Links Between Lipids and Colorectal Cancer Risk
- 2022
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research. - 1055-9965 .- 1538-7755. ; 31:6, s. 1216-1226
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Tidskriftsartikel (refereegranskat)abstract
- Background: The etiology of colorectal cancer is not fully understood.Methods: Using genetic variants and metabolomics data including 217 metabolites from the Framingham Heart Study (n = 1,357), we built genetic prediction models for circulating metabolites. Models with prediction R2 > 0.01 (Nmetabolite = 58) were applied to predict levels of metabolites in two large consortia with a combined sample size of approximately 46,300 cases and 59,200 controls of European and approximately 21,700 cases and 47,400 controls of East Asian (EA) descent. Genetically predicted levels of metabolites were evaluated for their associations with colorectal cancer risk in logistic regressions within each racial group, after which the results were combined by meta-analysis.Results: Of the 58 metabolites tested, 24 metabolites were significantly associated with colorectal cancer risk [Benjamini-Hochberg FDR (BH-FDR) < 0.05] in the European population (ORs ranged from 0.91 to 1.06; P values ranged from 0.02 to 6.4 × 10-8). Twenty one of the 24 associations were replicated in the EA population (ORs ranged from 0.26 to 1.69, BH-FDR < 0.05). In addition, the genetically predicted levels of C16:0 cholesteryl ester was significantly associated with colorectal cancer risk in the EA population only (OREA: 1.94, 95% CI, 1.60−2.36, P = 2.6 × 10-11; OREUR: 1.01, 95% CI, 0.99−1.04, P = 0.3). Nineteen of the 25 metabolites were glycerophospholipids and triacylglycerols (TAG). Eighteen associations exhibited significant heterogeneity between the two racial groups (PEUR-EA-Het < 0.005), which were more strongly associated in the EA population. This integrative study suggested a potential role of lipids, especially certain glycerophospholipids and TAGs, in the etiology of colorectal cancer.Conclusions: This study identified potential novel risk biomarkers for colorectal cancer by integrating genetics and circulating metabolomics data.Impact: The identified metabolites could be developed into new tools for risk assessment of colorectal cancer in both European and EA populations.
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| 2. |
- Hyun, Gyu Hwan, et al.
(författare)
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Multivalent Carbohydrate Nanocomposites for Tumor Microenvironment Remodeling to Enhance Antitumor Immunity
- 2023
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Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 17:12, s. 11567-11582
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Tidskriftsartikel (refereegranskat)abstract
- Current cancer immunotherapeutic strategies mainly focus on remodeling the tumor microenvironment (TME) to make it favorable for antitumor immunity. Increasing attention has been paid to developing innovative immunomodulatory adjuvants that can restore weakened antitumor immunity by conferring immunogenicity to inflamed tumor tissues. Here, a galactan-enriched nanocomposite (Gal-NC) is developed from native carbohydrate structures through an optimized enzymatic transformation for effective, stable, and biosafe innate immunomodulation. Gal-NC is characterized as a carbohydrate nanoadjuvant with a macrophage-targeting feature. It is composed of repeating galactan glycopatterns derived from heteropolysaccharide structures of plant origin. The galactan repeats of Gal-NC function as multivalent pattern-recognition sites for Toll-like receptor 4 (TLR4). Functionally, Gal-NC-mediated TLR activation induces the repolarization of tumor-associated macrophages (TAMs) toward immunostimulatory/tumoricidal M1-like phenotypes. Gal-NC increases the intratumoral population of cytotoxic T cells, the main effector cells of antitumor immunity, via re-educated TAMs. These TME alterations synergistically enhance the T-cell-mediated antitumor response induced by αPD-1 administration, suggesting that Gal-NC has potential value as an adjuvant for immune checkpoint blockade combination therapies. Thus, the Gal-NC model established herein suggests a glycoengineering strategy to design a carbohydrate-based nanocomposite for advanced cancer immunotherapies.
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| 3. |
- Kanoni, Stavroula, et al.
(författare)
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Implicating genes, pleiotropy, and sexual dimorphism at blood lipid loci through multi-ancestry meta-analysis.
- 2022
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Ingår i: Genome biology. - : Springer Science and Business Media LLC. - 1474-760X .- 1465-6906 .- 1474-7596. ; 23:1
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Tidskriftsartikel (refereegranskat)abstract
- Genetic variants within nearly 1000 loci are known to contribute to modulation of blood lipid levels. However, the biological pathways underlying these associations are frequently unknown, limiting understanding of these findings and hindering downstream translational efforts such as drug target discovery.To expand our understanding of the underlying biological pathways and mechanisms controlling blood lipid levels, we leverage a large multi-ancestry meta-analysis (N=1,654,960) of blood lipids to prioritize putative causal genes for 2286 lipid associations using six gene prediction approaches. Using phenome-wide association (PheWAS) scans, we identify relationships of genetically predicted lipid levels to other diseases and conditions. We confirm known pleiotropic associations with cardiovascular phenotypes and determine novel associations, notably with cholelithiasis risk. We perform sex-stratified GWAS meta-analysis of lipid levels and show that 3-5% of autosomal lipid-associated loci demonstrate sex-biased effects. Finally, we report 21 novel lipid loci identified on the X chromosome. Many of the sex-biased autosomal and X chromosome lipid loci show pleiotropic associations with sex hormones, emphasizing the role of hormone regulation in lipid metabolism.Taken together, our findings provide insights into the biological mechanisms through which associated variants lead to altered lipid levels and potentially cardiovascular disease risk.
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| 4. |
- Abolfathi, Bela, et al.
(författare)
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The Fourteenth Data Release of the Sloan Digital Sky Survey : First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
- 2018
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Ingår i: Astrophysical Journal Supplement Series. - : IOP Publishing Ltd. - 0067-0049 .- 1538-4365. ; 235:2
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Tidskriftsartikel (refereegranskat)abstract
- The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.
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| 5. |
- Blanton, Michael R., et al.
(författare)
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Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
- 2017
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Ingår i: Astronomical Journal. - : IOP Publishing Ltd. - 0004-6256 .- 1538-3881. ; 154:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and. high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z similar to 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z similar to 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs. and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the. Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.
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| 6. |
- Cai, Liangliang, et al.
(författare)
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Direct Formation of C-C Double-Bonded Structural Motifs by On-Surface Dehalogenative Homocoupling of gem-Dibromomethyl Molecules
- 2018
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Ingår i: ACS Nano. - : AMER CHEMICAL SOC. - 1936-0851 .- 1936-086X. ; 12:8, s. 7959-7966
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Tidskriftsartikel (refereegranskat)abstract
- Conductive polymers are of great importance in a variety of chemistry-related disciplines and applications. The recently developed bottom-up on-surface synthesis strategy provides us with opportunities for the fabrication of various nanostructures in a flexible and facile manner, which could be investigated by high-resolution microscopic techniques in real space. Herein, we designed and synthesized molecular precursors functionalized with benzal gem-dibromomethyl groups. A combination of scanning tunneling microscopy, noncontact atomic force microscopy, high-resolution synchrotron radiation photoemission spectroscopy, and density functional theory calculations demonstrated that it is feasible to achieve the direct formation of C-C double-bonded structural motifs via on-surface dehalogenative homocoupling reactions on the Au(111) surface. Correspondingly, we convert the sp(3)-hybridized state to an sp(2)-hybridized state of carbon atoms, i.e., from an alkyl group to an alkenyl one. Moreover, by such a bottom-up strategy, we have successfully fabricated poly(phenylenevinylene) chains on the surface, which is anticipated to inspire further studies toward understanding the nature of conductive polymers at the atomic scale.
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| 7. |
- Chang, Keke, et al.
(författare)
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Considerations on Circuit Design and Data Acquisition of a Portable Surface Plasmon Resonance Biosensing System
- 2015
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Ingår i: Sensors. - : MDPI AG. - 1424-8220. ; 15:8, s. 20511-20523
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to develop a circuit for an inexpensive portable biosensing system based on surface plasmon resonance spectroscopy. This portable biosensing system designed for field use is characterized by a special structure which consists of a microfluidic cell incorporating a right angle prism functionalized with a biomolecular identification membrane, a laser line generator and a data acquisition circuit board. The data structure, data memory capacity and a line charge-coupled device (CCD) array with a driving circuit for collecting the photoelectric signals are intensively focused on and the high performance analog-to-digital (A/D) converter is comprehensively evaluated. The interface circuit and the photoelectric signal amplifier circuit are first studied to obtain the weak signals from the line CCD array in this experiment. Quantitative measurements for validating the sensitivity of the biosensing system were implemented using ethanol solutions of various concentrations indicated by volume fractions of 5%, 8%, 15%, 20%, 25%, and 30%, respectively, without a biomembrane immobilized on the surface of the SPR sensor. The experiments demonstrated that it is possible to detect a change in the refractive index of an ethanol solution with a sensitivity of 4.99838 × 10(5) ΔRU/RI in terms of the changes in delta response unit with refractive index using this SPR biosensing system, whereby the theoretical limit of detection of 3.3537 × 10(-5) refractive index unit (RIU) and a high linearity at the correlation coefficient of 0.98065. The results obtained from a series of tests confirmed the practicality of this cost-effective portable SPR biosensing system.
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| 8. |
- Heald, G., et al.
(författare)
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Magnetism science with the square kilometre array
- 2020
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Ingår i: Galaxies. - : MDPI AG. - 2075-4434. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- The Square Kilometre Array (SKA) will answer fundamental questions about the origin, evolution, properties, and influence of magnetic fields throughout the Universe. Magnetic fields can illuminate and influence phenomena as diverse as star formation, galactic dynamics, fast radio bursts, active galactic nuclei, large-scale structure, and dark matter annihilation. Preparations for the SKA are swiftly continuing worldwide, and the community is making tremendous observational progress in the field of cosmic magnetism using data from a powerful international suite of SKA pathfinder and precursor telescopes. In this contribution, we revisit community plans for magnetism research using the SKA, in light of these recent rapid developments. We focus in particular on the impact that new radio telescope instrumentation is generating, thus advancing our understanding of key SKA magnetism science areas, as well as the new techniques that are required for processing and interpreting the data. We discuss these recent developments in the context of the ultimate scientific goals for the SKA era.
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| 9. |
- Ji, Xiang, et al.
(författare)
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Dissemination of extended-spectrum beta-lactamase-producing Escherichia coli carrying mcr-1 among multiple environmental sources in rural China and associated risk to human health
- 2019
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Ingår i: Environmental Pollution. - : ELSEVIER SCI LTD. - 0269-7491 .- 1873-6424. ; 251, s. 619-627
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Tidskriftsartikel (refereegranskat)abstract
- Antibiotic resistance among gram-negative bacteria is increasingly becoming a problem of global concern. Particularly problematic is the emergence of resistance to last-resort antibiotics such as carbapenems and colistin. The increasing number of reports on the plasmid-mediated colistin resistance gene mcr-1 in isolates worldwide is raising concerns for the future usefulness of this class of antibiotics. Dissemination of mcr-1 is believed to have originated mainly from animal breeding, however, the role of the environment as a transmission source is not yet fully understood. In the current study, 89 extended spectrum beta-lactamase-producing Escherichia coli isolated from 231 samples from different environmental sources in 12 villages in a rural area of Shandong, China, were screened for mcr-1.17 (19.1%) mcr-1-positive isolates were found from different environmental sources, aggregated in 6 villages. Plasmids of three different Inc-groups carrying mcr-1 were confirmed, indicating that the widespread geographical distribution of mcr-1 in the local area is due to a number of different plasmids. Additionally, almost a third (29.4%) of the isolates carried virulence factors associated to intestinal pathogenic E. coli. These results illustrate the high complexity of the transmission patterns of mcr-1 among different environmental matrices on a local scale and the potential for the environment to facilitate dissemination and emergence of antibiotic-resistant and virulent strains of bacteria. (C) 2019 Elsevier Ltd. All rights reserved.
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| 10. |
- Li, Yongqiang, et al.
(författare)
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Activation of locally excavated spoil for utilization in limestone calcined clay cement (LC3)
- 2024
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Ingår i: Construction and Building Materials. - 0950-0618. ; 420
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Tidskriftsartikel (refereegranskat)abstract
- The utilization of clay to produce limestone calcined clay cement (LC3) is limited in China due to environmental concerns related to clay excavation. This study explores the potential to activate the fine-grained clay sourced from excavated spoil in Shenzhen, China for LC3 production. A water washing method was introduced to treat the excavated spoil, enriching the clays’ kaolinite content in a range of 72.4–83.1%. Incorporation of calcined clay with different calcination procedures will modify the hydration rate for aluminate, and the longer calcination after 2 h is detrimental for clay reactivity. Additionally, using excavated spoil calcined at 800 °C with more than 2 h in paste yields compressive strength comparable to that of paste made of ordinary Portland cement (OPC). Calcining at 800 °C for 2 h is the optimal calcination procedure to activate the collected soil. Notably, this activation approach for LC3 production exhibits remarkable environmental and economic benefits, reinforcing the potential for extensive adoption of LC3 within China.
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| 11. |
- Liang, Xifeng, et al.
(författare)
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On the aerodynamic loads when a high speed train passes under an overhead bridge
- 2020
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Ingår i: Journal of Wind Engineering and Industrial Aerodynamics. - : Elsevier BV. - 0167-6105. ; 202
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Tidskriftsartikel (refereegranskat)abstract
- The aerodynamic loads on the overhead bridge bottom surface induced by train passage are reported in this paper. Both moving model test and numerical simulation approaches at the 1:20 scale are used. The numerical work is validated through both mesh independence tests and comparison with experimental data. Typical pressure variation curves are plotted and compared with previous studies. The peak pressure values’ dependence on the Reynolds number is considered through four sets of experiments with different train running speeds. The peak pressure coefficient distribution law for the bridge bottom surface is presented. Differences in the pressure distribution in different bridge bottom areas are explained based on more detailed flow field information. The influence of the bridge height on the aerodynamic load magnitude and time interval is presented. Moreover, the application of the CEN Standard to practical engineering issues is discussed.
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| 12. |
- Lin, Xiaojing, et al.
(författare)
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Metal-enriched Neutral Gas Reservoir around a Strongly Lensed Low-mass Galaxy at z = 4 Identified by JWST/NIRISS and VLT/MUSE
- 2023
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 944:2
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Tidskriftsartikel (refereegranskat)abstract
- Direct observations of low-mass, low-metallicity galaxies at z ≳ 4 provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the universe. Combining the James Webb Space Telescope (JWST), Very Large Telescope/MUSE, and Atacama Large Millimeter/submillimeter Array, we present detailed observations of a strongly lensed, low-mass (≈107.6 M ⊙) galaxy at z = 3.98 (also see Vanzella et al.). We identify strong narrow nebular emission, including C iv λ λ1548, 1550, He ii λ1640, O iii] λ λ1661, 1666, [Ne iii] λ3868, [O ii] λ3727, and the Balmer series of hydrogen from this galaxy, indicating a metal-poor H ii region (≲0.12 Z ⊙) powered by massive stars. Further, we detect a metal-enriched damped Lyα system (DLA) associated with the galaxy with the H i column density of N H I ≈ 1021.8 cm−2. The metallicity of the associated DLA may reach the supersolar metallicity (≳Z ⊙). Moreover, thanks to JWST and gravitational lensing, we present the resolved UV slope (β) map at the spatial resolution of ≈100 pc at z = 4, with steep UV slopes reaching β ≈ −2.5 around three star-forming clumps. Combining with low-redshift analogs, our observations suggest that low-mass, low-metallicity galaxies, which dominate reionization, could be surrounded by a high covering fraction of the metal-enriched, neutral-gaseous clouds. This implies that the metal enrichment of low-mass galaxies is highly efficient, and further supports that in low-mass galaxies, only a small fraction of ionizing radiation can escape through the interstellar or circumgalactic channels with low-column-density neutral gas.
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| 13. |
- Luo, Lifang, et al.
(författare)
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BCAT1 decreases the sensitivity of cancer cells to cisplatin by regulating mTOR-mediated autophagy via branched-chain amino acid metabolism
- 2021
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Ingår i: Cell Death and Disease. - : Springer Science and Business Media LLC. - 2041-4889. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- Cisplatin is one of the most effective chemotherapy drugs and is widely used in the treatment of cancer, including hepatocellular carcinoma (HCC) and cervical cancer, but its therapeutic benefit is limited by the development of resistance. Our previous studies demonstrated that BCAT1 promoted cell proliferation and decreased cisplatin sensitivity in HCC cells. However, the exact role and mechanism of how BCAT1 is involved in cisplatin cytotoxicity remain undefined. In this study, we revealed that cisplatin triggered autophagy in cancer cells, with an increase in BCAT1 expression. The cisplatin-induced up-regulation of BCAT1 decreased the cisplatin sensitivity by regulating autophagy through the mTOR signaling pathway. In addition, branched-chain amino acids or leucine treatment inhibited cisplatin- or BCAT1-mediated autophagy and increased cisplatin sensitivity by activating mTOR signaling in cancer cells. Moreover, inhibition of autophagy by chloroquine increased cisplatin sensitivity in vivo. Also, the knockdown of BCAT1 or the administration of leucine activated mTOR signaling, inhibited autophagy, and increased cisplatin sensitivity in cancer cells in vivo. These findings demonstrate a new mechanism, revealing that BCAT1 decreases cisplatin sensitivity in cancer cells by inducing mTOR-mediated autophagy via branched-chain amino acid leucine metabolism, providing an attractive pharmacological target to improve the effectiveness of chemotherapy.
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| 14. |
- Ma, Xiaotong, et al.
(författare)
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Association of sdLDL-C With Incident Carotid Plaques With Stable and Vulnerable Morphology : A Prospective Cohort Study
- 2024
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Ingår i: Stroke. - 0039-2499 .- 1524-4628. ; 55:3, s. 576-585
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Small dense low-density lipoprotein cholesterol (sdLDL-C) particles are more atherogenic than large and intermediate low-density lipoprotein cholesterol (LDL-C) subfractions. We sought to investigate the association of sdLDL-C and the sdLDL-C/LDL-C ratio with incident carotid plaques with stable and vulnerable morphology in rural China.METHODS: This community-based cohort study used data from the RICAS study (Rose Asymptomatic Intracranial Artery Stenosis), which enrolled 887 participants (aged ≥40 years) who were living in Kongcun Town, Pingyin County, Shandong, and free of carotid plaques and had no history of clinical stroke or transient ischemic attack at baseline (2017). Incident carotid plaques and their vulnerability were detected by carotid ultrasound at follow-up (2021). Multivariable logistic regression models were used to explore the association of sdLDL-C or sdLDL-C/LDL-C ratio with incident carotid plaques while adjusting for demographic factors, vascular risk factors, and follow-up time.RESULTS: Of the 887 participants (mean age [SD], 53.89 [8.67%] years; 54.34% women), 179 (20.18%) were detected with incident carotid plaques during an average follow-up of 3.94 years (SD=0.14). Higher sdLDL-C or sdLDL-C/LDL-C ratio, but not LDL-C, was significantly associated with an increased risk of incident carotid plaques. The upper tertile of sdLDL-C (versus lower tertile) was associated with the multivariate-adjusted odds ratio of 2.48 (95% CI, 1.00–6.15; P=0.049; P for linear trend=0.046) for carotid plaques with vulnerable morphology (n=41), and the association remained significant in participants with normal LDL-C (<130 mg/dL; n=693; upper versus lower tertile: odds ratio, 3.38 [95% CI, 1.15–9.90]; P=0.027; P for linear trend=0.025). Moreover, the sdLDL-C/LDL-C ratio was associated with a higher odds ratio of incident carotid plaques in participants without diabetes (P for interaction=0.014).CONCLUSIONS: Higher sdLDL-C was associated with an increased risk of incident carotid plaques, especially carotid plaques with vulnerable morphology, even in participants with normal LDL-C. This suggests the potential of sdLDL-C as a therapeutic target for stroke prevention.
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| 15. |
- Postmus, Iris, et al.
(författare)
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Pharmacogenetic meta-analysis of genome-wide association studies of LDL cholesterol response to statins.
- 2014
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Statins effectively lower LDL cholesterol levels in large studies and the observed interindividual response variability may be partially explained by genetic variation. Here we perform a pharmacogenetic meta-analysis of genome-wide association studies (GWAS) in studies addressing the LDL cholesterol response to statins, including up to 18,596 statin-treated subjects. We validate the most promising signals in a further 22,318 statin recipients and identify two loci, SORT1/CELSR2/PSRC1 and SLCO1B1, not previously identified in GWAS. Moreover, we confirm the previously described associations with APOE and LPA. Our findings advance the understanding of the pharmacogenetic architecture of statin response.
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| 16. |
- Sun, Weian, et al.
(författare)
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In situ LA-ICP-MS trace element analyses of magnetite : genetic implications for the Zhonggu orefield, Ningwu volcanic basin, Anhui Province, China
- 2019
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Ingår i: Mineralium Deposita. - : SPRINGER. - 0026-4598 .- 1432-1866. ; 54:8, s. 1243-1264
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Tidskriftsartikel (refereegranskat)abstract
- The Zhonggu orefield is located within the southern Ningwu volcanic basin and is one of the largest iron ore districts within the Middle-Lower Yangtze River Metallogenic Belt (MLYRMB) of eastern China. The area hosts the Gushan iron oxide-apatite (IOA) deposit and the Baixiangshan, Longshan, Hemushan, Zhongjiu, and Taipingshan skarn-type iron deposits. Here, we employ laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to determine trace element concentrations in magnetite from these deposits. Combining these new data with geological information from these deposits indicates that the iron ore within the Gushan deposit has V and Ti compositions that are strongly suggestive of a Kiruna-type IOA origin. Specifically, the V and Ti chemistry of magnetite in iron ore breccias from the Gushan deposit suggests that this style of mineralization formed at a high temperature and as a result of magmatic magnetite precipitation. This was followed by precipitation of lower temperature magmatic-hydrothermal massive magnetite. Both types of magnetite host exsolved ilmenite. Elemental mapping also indicates that Gushan breccia-hosted magnetite records hydrothermal fluid activity that formed late-stage vein mineralization. In comparison, other deposits within the Zhonggu orefield all contain magnetite with compositions that are indicative of skarn mineralization. This implies that these deposits formed as a result of magmatic-hydrothermal rather than purely magmatic or purely hydrothermal activity, contrasting with the Gushan deposit. Finally, the geochemistry of magnetite within thick anhydrite units in the Longshan deposit indicates the formation by low-temperature sedimentary processes, and this magnetite was subsequently overprinted as a result of hydrothermal activity during the formation of the main Longshan deposit. Overall, this study indicates that the IOA, skarn-type, and sedimentary anhydrite-type iron mineralization in the Zhonggu iron ore field record evolving metallogenic processes from initially orthomagmatic mineralizing systems to high- to moderate-temperature magmatic-hydrothermal systems and finally to low-temperature hydrothermal mineralization.
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| 17. |
- Wang, Jixiang, et al.
(författare)
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Surface-imprinted fluorescence microspheres as ultrasensitive sensor for rapid and effective detection of tetracycline in real biological samples
- 2018
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Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 263, s. 533-542
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Tidskriftsartikel (refereegranskat)abstract
- Molecularly imprinted fluorescence sensors have shown great promise in environmental or biological monitoring and due to its high stability, selectivity and sensitivity. In this study, a fluorescence surface imprinted sensor (SiO2-AF@MIPs) towards tetracycline (TC) was successfully prepared to address the shortcomings in current molecularly imprinted fluorescent sensor, such as slow response, limited detection and deteriorated performance in real complex samples. Benefited from the thin surface-imprinting layer, the SiO2-AF@MIPs sensors showed higher sensitivity (LOD low to 4.26 nM), rapid detection rate, reusable performance and excellent selectivity over several target competitors. Furthermore, the fluorescence sensor could efficiently detect TC in real biological samples, including tetracycline hydrochloride injection, human serum and swine urine. These results clearly demonstrated the potential value of this smart sensor nanomaterial in environmental monitoring and biological diagnosis. (C) 2018 Elsevier B.V. All rights reserved.
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| 18. |
- Xu, Kangjun, et al.
(författare)
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Association between serum vitamin B12 and risk of all-cause mortality in elderly adults : a prospective cohort study
- 2021
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Ingår i: BMC Geriatrics. - : BioMed Central. - 1471-2318. ; 21:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND PURPOSE: Results from previous studies that linking vitamin B12 to risk of chronic diseases or mortality are inconsistent. We hereby explore the association between serum concentration of vitamin B12 and all-cause mortality risk in elderly adults.METHODS: Participants aged over 65 years in the Chinese Longitudinal Healthy Longevity Survey were included in present prospective cohort study. Serum vitamin B12 was assessed at the 2011-2012 and 2014 wave, respectively. Participants were divided into three groups based on two cut-off points - 10th and 90th percentiles of vitamin B12 concentrations - in the whole population. Cox regression model was used to calculate the hazard ratio (HR) and 95 % confidence intervals (95 % CIs), and restricted cubic spline function was further modelled to investigate their dose-response associations.RESULTS: Among 2,086 participants [mean ± SD: 87.74 ± 11.24 years, 908 (43.53 %) males], 943 (45.21 %) died during an average follow-up of 3.34 (SD: 1.63) years. Comparing with participants with middle concentration of serum vitamin B12, participants with high concentration had an increased risk of all-cause mortality [HR (95 %CIs): 1.30 (1.03-1.64)], whereas participants with low concentration had an insignificantly decreased risk of all-cause mortality (0.96, 0.76-1.20). The positive association between high concentration of serum vitamin B12 and all-cause mortality was also observed among the male and in a series of sensitivity analyses. In the dose-response analysis, a J-shape pattern was observed, but the non-linear association was only significant in males (Pnon-linearity = 0.0351).CONCLUSIONS: High concentration of serum vitamin B12 was associated with an increased risk of all-cause mortality in a J-shaped pattern. The precise mechanisms underlying the association remain to be explored.
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| 19. |
- Zou, Huiyun, et al.
(författare)
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Evaluating Dissemination Mechanisms of Antibiotic-Resistant Bacteria in Rural Environments in China by Using CTX-M-Producing Escherichia coli as an Indicator
- 2019
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Ingår i: Microbial Drug Resistance. - : Mary Ann Liebert, Inc., publishers. - 1076-6294 .- 1931-8448. ; 25:7, s. 975-984
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Tidskriftsartikel (refereegranskat)abstract
- It is becoming increasingly recognized that the environment plays an important role both in the emergence and in dissemination of antibiotic-resistant bacteria (ARB), Mechanisms and factors facilitating this development are, however, not yet well understood. The high detection rate of CTX-M genes in environmental sources provides an opportunity to explore this issue. In this study, 88 CTX-M-producing Escherichia coli were isolated from 30 pig feces samples from 30 pig farms and 201 environmental samples. CTX-M-producing E. coli was detected with the following frequencies in the different types of samples: pig feces, 73%; river water, 64%; river sediment, 52%; wastewater, 31%; drinking water, 23%; outlet sediment, 21%; soil, 17%; and vegetables, 4.4%. Dissemination of CTX-M-producing E. coli to different environmental matrices was evaluated by analyzing the genetic relatedness of isolates from different environmental sources, and putative transmission routes through bird feces, pig feces, drinking water, river sediment, river water, and wastewater were hypothesized. Dissemination through these routes is likely facilitated by anthropogenic activities and environmental factors. Wild birds as potential vectors for dissemination of CTX-M-producing E. coli have the capacity to spread ARB across long distances. Regional dissemination between different environmental matrices of CTX-M-producing E. coli increases the exposure risk of humans and animals in the area.
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