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1.
Food Funct ; 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503268

RESUMO

Nonalcoholic steatohepatitis (NASH) increases hepatocellular carcinoma (HCC) risk. We hypothesized that the hepatoprotective anti-inflammatory benefits of catechin-rich green tea extract (GTE) would protect against HCC progression by inhibiting NASH-associated liver injury and pro-oncogenic responses. We used an HCC model in high-fat (HF)-fed mice that mimics early oncogenic events during NASH without inducing tumorigenesis and premature mortality. Male C57BL/6J mice (4-weeks old) were fed a HF diet containing GTE at 0% or 2%. Mice were administered saline or diethylnitrosamine (DEN; 60 mg kg-1, i.p.) at 5-weeks and 7-weeks of age. NASH, inflammation, fibrosis, and oncogenic responses were assessed at 25-weeks of age. Saline-treated mice showed prominent histopathological signs of steatosis and hepatocellular ballooning. Although DEN did not impact adiposity, steatosis, ballooning and hepatic lipid accumulation, these parameters were attenuated by GTE regardless of DEN. Hepatic lipid peroxidation and fibrosis that were increased by DEN were attenuated by GTE. Hepatic TLR4, MCP1 and TNFα mRNA levels were unaffected by DEN, whereas iNOS was increased by DEN. These transcripts were lowered by GTE. GTE attenuated the frequency of PCNA+ hepatocytes and mRNA expression of cyclin D1, MIB1 and Ki-67 that were otherwise increased by DEN. GTE increase APAF1 mRNA that was otherwise lowered by DEN. Relative to saline-treated mice, DEN increased mRNA levels of oncostatin M, gp130, c-Fos, c-Myc and survivin; each was lowered by GTE in DEN-treated mice. These findings indicate that GTE may protect against hepatic oncogenesis by limiting early steps in the carcinogenic cascade related to NASH-associated HCC.

2.
J Environ Manage ; 249: 109353, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31493685

RESUMO

Rare earth elements (REE), including neodymium, praseodymium, and dysprosium are used in a range of low-carbon technologies, such as electric vehicles and wind turbines, and demand for these REE is forecast to grow. This study demonstrates that a process simulation-based life cycle assessment (LCA) carried out at the early stages of a REE project, such as at the pre-feasibility stage, can inform subsequent decision making during the development of the project and help reduce its environmental impacts. As new REE supply chains are established and new mines are opened. It is important that the environmental consequences of different production options are examined in a life cycle context in order that the environment footprint of these raw materials is kept as low as possible. Here, we present a cradle-to-gate and process simulation-based life cycle assessment (LCA) for a potential new supply of REE at Songwe Hill in Malawi. We examine different project options including energy selection and a comparison of on-site acid regeneration versus virgin acid consumption which were being considered for the project. The LCA results show that the global warming potential of producing 1 kg of rare earth oxide (REO) from Songwe Hill is between 17 and 87 kg CO2-eq. A scenario that combines on-site acid regeneration with off-peak hydroelectric and photovoltaic energy gives the lowest global warming potential and performs well in other impact categories. This approach can equally well be applied to all other types of ore deposits and should be considered as a routine addition to all pre-feasibility studies.

3.
J Immunol ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501257

RESUMO

Glutathione reductase (Gsr) catalyzes the reduction of glutathione disulfide to glutathione, which plays an important role in redox regulation. We have previously shown that Gsr facilitates neutrophil bactericidal activities and is pivotal for host defense against bacterial pathogens. However, it is unclear whether Gsr is required for immune defense against fungal pathogens. It is also unclear whether Gsr plays a role in immunological functions outside of neutrophils during immune defense. In this study, we report that Gsr-/- mice exhibited markedly increased susceptibility to Candida albicans challenge. Upon C. albicans infection, Gsr-/- mice exhibited dramatically increased fungal burden in the kidneys, cytokine and chemokine storm, striking neutrophil infiltration, histological abnormalities in both the kidneys and heart, and substantially elevated mortality. Large fungal foci surrounded by massive numbers of neutrophils were detected outside of the glomeruli in the kidneys of Gsr -/- mice but were not found in wild-type mice. Examination of the neutrophils and macrophages of Gsr-/- mice revealed several defects. Gsr -/- neutrophils exhibited compromised phagocytosis, attenuated respiratory burst, and impaired fungicidal activity in vitro. Moreover, upon C. albicans stimulation, Gsr -/- macrophages produced increased levels of inflammatory cytokines and exhibited elevated p38 and JNK activities, at least in part, because of lower MAPK phosphatase (Mkp)-1 activity and greater Syk activity. Thus, Gsr-mediated redox regulation is crucial for fungal clearance by neutrophils and the proper control of the inflammatory response by macrophages during host defense against fungal challenge.

4.
Medicine (Baltimore) ; 98(27): e16205, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277128

RESUMO

With the advances in sequencing technologies and genome-wide association studies (GWAS), several inherited variants that increase glioma risk have been identified. Ten studies including 8818 cases and 17,551 controls were collected to conduct a meta-analysis to evaluate the associations between 6 variants in 8q24 and glioma risk. Of the 6 variants located in 8q24, 2 have strong significant associations with the risk of glioma, including rs4295627 (P = .003, odds ratio [OR] = 1.21), rs55705857 (P = 2.31 × 10, OR = 3.54). In particular, both homozygous GG (P = 1.91 × 10, OR1 = 2.01) and heterozygous GT (P = 7.75 × 10, OR2 = 1.35) genotypes of rs4295627 were associated with glioma risk. Further studies are needed to explore the role of the 8q24 variants involved in the etiology of glioma.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 8/genética , Estudo de Associação Genômica Ampla/métodos , Glioma/genética , Polimorfismo de Nucleotídeo Único , Alelos , Predisposição Genética para Doença , Genótipo , Humanos , Fatores de Risco
5.
EMBO J ; 38(17): e101051, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31328806

RESUMO

VGLL4 has previously been identified as a negative regulator of YAP. Here we show that VGLL4 regulates muscle regeneration in both YAP-dependent and YAP-independent manners at different stages. Knockout of VGLL4 in mice leads to smaller myofiber size and defective muscle contraction force. Furthermore, our studies reveal that knockout of VGLL4 results in increased muscle satellite cells proliferation and impaired myoblast differentiation, which ultimately leads to delayed muscle regeneration. Mechanistically, the results show that VGLL4 works as a conventional repressor of YAP at the proliferation stage of muscle regeneration. At the differentiation stage, VGLL4 acts as a co-activator of TEAD4 to promote MyoG transactivation and facilitate the initiation of differentiation in a YAP-independent manner. Moreover, VGLL4 stabilizes the protein-protein interactions between MyoD and TEAD4 to achieve efficient MyoG transactivation. Our findings define the dual roles of VGLL4 in regulating muscle regeneration at different stages and may open novel therapeutic perspectives for muscle regeneration.

6.
J Hazard Mater ; 380: 120846, 2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31279946

RESUMO

The separation of cathode materials from aluminum (Al) foil is a key issue worthy of attention in the process of resource utilization of spent lithium-ion batteries (LIBs). Traditional technologies for the Al foil and cathode materials separation have the disadvantages of the use of corrosive acid/alkali, release of HF hazards, and environment and healthy risks of the toxicity reagent. In this study, a low-toxicity, high-efficiency, and low-cost deep eutectic solvent (DES), choline chloride-glycerol, was synthesized and applied to solving the separation dilemma of Al foil and cathode materials in spent LIBs. The experimental results show that separation of the Al foil and cathode materials can be achieved under optimal conditions designed by the response surface method: heating temperature 190 ℃, choline chloride: glycerol molar ratio 2.3:1, and heating time 15.0 min; the peeling percentage of cathode material can reach 99.86 wt%. Mechanism analysis results confirm that the separation of Al foil and cathode materials was the result of the deactivation of the organic binder polyvinylidene fluoride (PVDF), which can be attributed to an alkali degradation process caused by the attack of the hydroxide of choline chloride on the acidic hydrogen atom in PVDF.

7.
J Hazard Mater ; 380: 120898, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31330384

RESUMO

Mobile phones and various electronic products contribute to the world's fastest-growing category of hazardous waste with international repercussions. We investigated the trends in potential human health impacts and ecotoxicity of waste mobile phones through quantitative life cycle impact assessment (LCIA) methods and regulatory total threshold limit concentrations. A market-dominant sample of waste basic phones and smartphones manufactured between 2001 and 2015, were analyzed for toxicity trends based on 19 chemicals. The results of the LCIA (using USEtox model) show an increase in the relative mass of toxic materials over the 15-year period. We found no significant changes in the use of toxic components in basic phones, whereas smartphones contained a statistically significant increase in the content of toxic materials from 2006 to 2015. Nickel contributed the largest risk for carcinogens in mobile phones, but the contributions of lead and beryllium were also notable. Silver, zinc and copper contents were associated with non-cancer health risks. Copper components at 45,818-77,938 PAF m3/kg dominated ecotoxicity risks in mobile phones. Overall, these results highlight the increasing importance of monitoring trends in materials use for electronic product manufacturing and electronic-waste management processes that should prevent human and environmental exposures to toxic components.

8.
Sci Total Environ ; 689: 332-340, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31277001

RESUMO

Gallium is one such co-product mineral, being used for consumer electronics and contemporary renewable energy applications. China is the top producer of gallium and supplies over 70% of global demand. However, supply uncertainty of primary gallium is increasing due to a shortage of reserves. Thus, development of recycling technologies to complement primary production should be prioritized, with more country-specific attention due to its low investment cost and short-term feasibility. In this study, possible end-of-life (EoL) gallium waste generation in China until 2050 was forecasted using linear regression and constructed a scenario analysis based on population and annual demand growth parameters. Similarly, cumulative domestic demand was estimated using 1%, 5%, 10%, 15%, 20%, and 30% recycling rates to investigate the effect of recycling on sustainability of gallium resources. Based on the used method, study results were different; however, continuous demand growth and resource use are expected in most cases. The annual total gallium stock generation in 2050 will reach to 368 t under linear regression forecasting while it will likely fall between 59 t and 148 t according to scenario analysis. Linear projections show that cumulative demand will surpass even reserve base in 2047 whilst scenario analyses demonstrate that cumulative demand will exceed reserve between 2037 and 2047, if there would be unable to implement necessary recycling routes in the short term. The linear regression cumulative demand prediction urges the need of substitution, while the scenario analysis demonstrates the importance of increasing EoL recycling rates. The latter should also be supported with improved EoL collection rates, technological transfer from high-tech countries to China and appropriate policy advancement. The output of the study also convinces the importance of moving towards a circular economic model in the anthropogenic flow of gallium utilization.

9.
Environ Sci Technol ; 53(16): 9781-9788, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31339306

RESUMO

Lithium (Li) is the most valuable metal in spent lithium iron phosphate (LiFePO4) batteries, but its recovery has become a challenge in electronic waste recovery because of its relatively low content and inconsistent quality. This study proposes an acid-free and selective Li extraction process to successfully achieve the isomorphic substitution of Li in LiFePO4 crystals with sodium (Na). The method uses low-cost and nontoxic sodium chloride (NaCl) as a cogrinding reagent via a mechanical force-induced solid-phase reaction. X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), and X-ray photoelectron spectroscopy (XPS) characterizations demonstrated the evidence of Li/Na isomorphic substitution, while XPS spectra of Fe 2p, P 2p, and O 1s revealed that the coordination environment of these elements was not significantly altered. Density functional theory calculations further provided evidence that Na and Li share similar outer electron arrangements and coordination environments, favoring Na over Fe as a replacement for Li in LiFePO4. Additionally, the regeneration of NaCl and the recovery of precipitated Li2CO3 were simultaneously achieved with Na2CO3 as the sole reagent. This concise and efficient acid-free mechanochemical process for Li extraction is a promising candidate for feasible recycling technology of Li from spent LiFePO4 batteries. The proposed process is particularly appealing because of its high selectivity, considerable economic advantages, and environmental benefits.

10.
N Engl J Med ; 381(1): 13-24, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31150574

RESUMO

BACKGROUND: Apalutamide is an inhibitor of the ligand-binding domain of the androgen receptor. Whether the addition of apalutamide to androgen-deprivation therapy (ADT) would prolong radiographic progression-free survival and overall survival as compared with placebo plus ADT among patients with metastatic, castration-sensitive prostate cancer has not been determined. METHODS: In this double-blind, phase 3 trial, we randomly assigned patients with metastatic, castration-sensitive prostate cancer to receive apalutamide (240 mg per day) or placebo, added to ADT. Previous treatment for localized disease and previous docetaxel therapy were allowed. The primary end points were radiographic progression-free survival and overall survival. RESULTS: A total of 525 patients were assigned to receive apalutamide plus ADT and 527 to receive placebo plus ADT. The median age was 68 years. A total of 16.4% of the patients had undergone prostatectomy or received radiotherapy for localized disease, and 10.7% had received previous docetaxel therapy; 62.7% had high-volume disease, and 37.3% had low-volume disease. At the first interim analysis, with a median of 22.7 months of follow-up, the percentage of patients with radiographic progression-free survival at 24 months was 68.2% in the apalutamide group and 47.5% in the placebo group (hazard ratio for radiographic progression or death, 0.48; 95% confidence interval [CI], 0.39 to 0.60; P<0.001). Overall survival at 24 months was also greater with apalutamide than with placebo (82.4% in the apalutamide group vs. 73.5% in the placebo group; hazard ratio for death, 0.67; 95% CI, 0.51 to 0.89; P = 0.005). The frequency of grade 3 or 4 adverse events was 42.2% in the apalutamide group and 40.8% in the placebo group; rash was more common in the apalutamide group. CONCLUSIONS: In this trial involving patients with metastatic, castration-sensitive prostate cancer, overall survival and radiographic progression-free survival were significantly longer with the addition of apalutamide to ADT than with placebo plus ADT, and the side-effect profile did not differ substantially between the two groups. (Funded by Janssen Research and Development; TITAN ClinicalTrials.gov number, NCT02489318.).


Assuntos
Adenocarcinoma/tratamento farmacológico , Antagonistas de Androgênios/uso terapêutico , Antagonistas de Receptores de Andrógenos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Tioidantoínas/uso terapêutico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/efeitos adversos , Antagonistas de Receptores de Andrógenos/efeitos adversos , Método Duplo-Cego , Exantema/induzido quimicamente , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Intervalo Livre de Progressão , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Qualidade de Vida , Radiografia , Tioidantoínas/efeitos adversos
11.
Chemistry ; 25(50): 11715-11724, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31241235

RESUMO

The practical application of advanced personalized electronics is inseparable from flexible, durable, and even self-healable energy storage devices. However, the mechanical and self-healing performance of supercapacitors is still limited at present. Herein, highly transparent, stretchable, and self-healable poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA)/poly(vinyl alcohol) (PVA)/LiCl polyelectrolytes were facilely prepared by one-step radical polymerization. The cooperation of PAMPSA and PVA significantly increased the mechanical and self-healing capacity of the polyelectrolyte, which exhibited superior stretchability of 938 %, stress of 112.68 kPa, good electrical performance (ionic conductivity up to 20.6 mS cm-1 ), and high healing efficiency of 92.68 % after 24 h. After assembly with polypyrrole-coated single-walled carbon nanotubes, the resulting as-prepared supercapacitor had excellent electrochemical properties with high areal capacitance of 297 mF cm-2 at 0.5 mA cm-2 and good rate capability (218 mF cm-2 at 5 mA cm-2 ). Besides, after cutting in two the supercapacitor recovered 99.2 % of its original specific capacitance after healing for 24 h at room temperature. The results also showed negligible change in the interior contact resistance of the supercapacitor after ten cutting/healing cycles. The present work provides a possible solution for the development of smart and durable energy storage devices with low cost for next-generation intelligent electronics.

12.
Brain Behav ; 9(7): e01335, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31154672

RESUMO

INTRODUCTION: Rambling natural landscapes or landscape gardens may invoke positive emotions. However, the manner in which people experience landscape gardens and the cortical differences in the appreciation of the naturalness and artificiality of landscapes remain unknown. METHODS: This study scanned participants with functional magnetic resonance imaging while they viewed photographs of natural landscapes and landscape gardens and performed scene type judgment task. RESULTS: As predicted, we identified brain regions that were associated with perceptual process, cognitive process, and rewarding experience when appreciating natural landscapes and landscape gardens without color preference. Meanwhile, the contrast between the appreciation of landscape gardens and natural landscapes was characterized by stronger activations of the inferior occipital lobe, the left superior parietal lobule (SPL), the right fusiform gyrus, the right cuneus, and the right hippocampus. CONCLUSIONS: Responses in these regions indicate that the appreciation of landscape gardens and natural landscapes relies on common cortical regions, and suggest the possibility that the inferior occipital lobe, the SPL, the fusiform gyrus, and the cuneus may be specifically associated with the appreciation of landscape gardens.

13.
PLoS One ; 14(5): e0216245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31048910

RESUMO

Senecavirus A (SVA) is a critical pathogen causing vesicular lesions in sows and acute death of newborn piglets, resulting in very large economic losses in the pig industry. To restrict the transmission of SVA, an establishment of an effective diagnostic method is crucial for the prevention and control of the disease. However, traditional detection methods often have many drawbacks. In this study, reverse transcription loop-mediated isothermal amplification (RT-LAMP) was combined with a lateral flow dipstick (LFD) to detect SVA. The resulting RT-LAMP-LFD assay was performed at 60°C for 50 min and then directly judged on an LFD visualization strip. This method shows high specificity and sensitivity to SVA. The detection limit of RT-LAMP was 4.56x10-8 ng/µL RNA, approximately 11 copies/µL RNA, and it was 10 times more sensitive than RT-PCR. This detection method's positive rate for clinical samples is comparable to that of RT-PCR. This method is time saving and highly efficient and is thus expected to be used to diagnose SVA infections in this field.

14.
BMJ Open ; 9(4): e025222, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31048432

RESUMO

OBJECTIVES: Our study aimed to synthesise and analyse the early diagnostic value of neutrophil CD11b (nCD11b) for neonatal sepsis. DESIGN: Systematic review and meta-analysis. METHODS: Pubmed, Embase, the Cochrane Library and Web of Science Databases were searched up to June 2018. We used Stata software (V.14.0) to conduct the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic OR (DOR), pretest probability, post-test probability and summary receiver operating characteristic (SROC) curve for diagnostic efficiency of n CD11b. RESULTS: Nine studies, accounting for 843 neonates, were included. The overall pooled sensitivity, specificity, PLR, NLR, DOR, post-test positive probability and post-test negative probability and the area under the SROC curve were 0.82 (95% CI 0.71 to 0.90), 0.93 (95% CI 0.62 to 0.99), 11.51 (95% CI 1.55 to 85.62), 0.19 (95% CI 0.10 to 0.36), 59.50 (95% CI 4.65 to 761.58), 74%, 5% and 0.90, which had accuracy in diagnosing neonatal sepsis. CONCLUSION: The present evidence indicated that nCD11b is a promising biomarker for the early diagnosis of neonatal sepsis.

15.
Inorg Chem ; 58(12): 8169-8178, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31141354

RESUMO

MoSe2 is a prospective anode material for Na-ion batteries because of its layered structure and high theoretical capacity, while the unsatisfied electrochemical performance limits its further development. Herein, we report MoSe2 nanosheets anchored on dual-heteroatoms functionalized graphene by a solvothermal method. The heteroatoms and carbon matrix coexist in the form of graphitic-N/pyridinic-N/pyrrolic-N and P-C/P═O bonds, which result in excellent electronic conductivity of the materials and provide abundant active sites for electrochemical process. Results indicated that organic intercalation increased the layer spacing of the materials to facilitate sodium-ion diffusion, and the in situ formed carbon networks improved the conductivity among the layers of the materials and alleviated volume expansion during the continued charge and discharge process. As an anode of Na-ion batteries, the nanosheets materials exhibited ultrahigh rate performance and deliver capacities of approximately 200 mAh g-1 at the current density of 10 A g-1. The ultrahigh-rate performance can be attributed to its unique nanosheets structure, the dual-heteroatoms functionalized graphene, and the considerable pseudocapacitive quality of the material.

16.
Opt Express ; 27(9): 13492-13502, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31052870

RESUMO

We developed an 808 nm diode laser pumped composite Holmium laser via the integration of Tm-doped and Ho-doped YAG crystals into a single bulk structure. A maximum output power of 1.8 W at 2122 nm with near diffraction-limited beam quality was achieved for an absorbed pump power of approximately 7 W. Given that the pump wavelength is approximately 20 nm away from the absorption peak of the Tm-doped region of the crystal, pump wavelength adaptability of the Tm/Ho composite laser was effectively demonstrated. In this case, a pump range width in excess of 40 nm at approximately 800 nm was predicted by defining the pump spectrum of the gain medium. The temperature adaptability of the Ho laser was demonstrated by varying the cooling temperature from 9 °C to 27 °C. This resulted in Ho laser operation above 1.5 W with a power deviation below 10%. This work presents the experimental results for a compact assessable 2.1 µm laser without pump wavelength and operation temperature restrictions.

17.
Dalton Trans ; 48(20): 6718-6729, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30945713

RESUMO

Heteroatom-doping engineering has been recognized as an effective strategy to improve the activity and stability of electrocatalytic materials. Herein, we fabricated a bimetallic Mo/Mn codoped three-phase nickel sulfide on Ni foam, with Mo/Mn-NixSy/NF successfully synthesized via hydrothermal synthesis and calcination. In order to better explore the codoping effect of Mo/Mn, we also synthesised Ni3S2/NF, NiS@Ni0.96S/NF, Mo-Ni3S2/NF and Mn-NiS@Ni0.96S/NF and their electrocatalytic activities (HER, OER, and overall water splitting) were systematically investigated. As expected, Mo/Mn-NixSy/NF catalysts exhibited excellent catalytic activities and long-term durability. High electrochemical performance of Mo/Mn-NixSy/NF exceeded that of most reported non-precious metal catalysts and also benchmark RuO2, IrO2 and Pt/C. Moreover, in order to better understand the catalytic process, three possible mechanisms were further proposed to rationalize the enhanced electrocatalytic performance. Our work might broaden the avenue to construct efficient non-precious bifunctional catalysts and further develop large-scale electricity-to-hydrogen applications.

18.
Dalton Trans ; 48(20): 7025, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30993282

RESUMO

Correction for 'Controlled synthesis of bifunctional particle-like Mo/Mn-NixSy/NF electrocatalyst for highly efficient overall water splitting' by Yaqiong Gong et al., Dalton Trans., 2019, DOI: 10.1039/c9dt00957d.

19.
J Nutr Biochem ; 67: 78-89, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30856467

RESUMO

Gut-derived endotoxin translocation provokes obesity by inducing TLR4/NFκB inflammation. We hypothesized that catechin-rich green tea extract (GTE) would protect against obesity-associated TLR4/NFκB inflammation by alleviating gut dysbiosis and limiting endotoxin translocation. Male C57BL/6J mice were fed a low-fat (LF) or high-fat (HF) diet containing 0% or 2% GTE for 8 weeks. At Week 7, fluorescein isothiocyanate (FITC)-dextran was administered by oral gavage before assessing its serum concentrations as a gut permeability marker. HF-feeding increased (P<.05) adipose mass and adipose expression of genes involved in TLR4/NFκB-dependent inflammation and macrophage activation. GTE attenuated HF-induced obesity and pro-inflammatory gene expression. GTE in HF mice decreased serum FITC-dextran, and attenuated portal vein and circulating endotoxin concentrations. GTE in HF mice also prevented HF-induced decreases in the expression of intestinal tight junction proteins (TJPs) and hypoxia inducible factor-1α while preventing increases in TLR4/NFκB-dependent inflammatory genes. Gut microbial diversity was increased, and the Firmicutes:Bacteroidetes ratio was decreased, in HF mice fed GTE compared with HF controls. GTE in LF mice did not attenuate adiposity but decreased endotoxin and favorably altered several gut bacterial populations. Serum FITC-dextran was correlated with portal vein endotoxin (P<.001; rP=0.66) and inversely correlated with colonic mRNA levels of TJPs (P<.05; rP=-0.38 to -0.48). Colonic TJPs mRNA were inversely correlated with portal endotoxin (P<.05; rP=-0.33 to -0.39). These data suggest that GTE protects against diet-induced obesity consistent with a mechanism involving the gut-adipose axis that limits endotoxin translocation and consequent adipose TLR4/NFκB inflammation by improving gut barrier function.

20.
Chemistry ; 25(25): 6378-6384, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30847982

RESUMO

Wearable sensors with excellent flexibility and sensitivity have emerged as a promising field for healthcare, electronic skin, and so forth. Three-dimensional (3D) graphene sponges (GS) have emerged as high-performance piezoresistive sensors; however, problems, such as limited flexibility, high cost, and low sensitivity, remain. Meanwhile, device-level wearable pressure sensors with GS have rarely been demonstrated. In this work, highly ordered 3D porous graphene sponges (OPGSs) were first successfully prepared and controlled through an emulsion method, and then a device-level wearable pressure sensor with high flexibility and sensitivity was assembled with a gold electrode and polydimethylsiloxane into a reliable package. The pH values were carefully controlled to form a stable emulsion and the OPGSs showed a highly ordered 3D structure with ultralow density, high porosity, and conductivity; this resulted in a gauge factor of 0.79-1.46, with 50 % compression strain and excellent long-term reproducibility over 500 cycles of compression-relaxation. Moreover, the well-packaged pressure sensor devices exhibited ultrahigh sensitivity to detect human motions, such as wrist bending, elbow bending, finger bending, and palm flexing. Thus, the developed pressure sensors exhibited great potential in the fields of human-interactive applications, biomechanical systems, electronic skin, and so forth.

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