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1.
Int J Biol Macromol ; 273(Pt 1): 132788, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38942669

ABSTRACT

Dye wastewater poses a serious threat to the environment and human health, necessitating sustainable degradation methods. In this study, Na-based Montmorillonite (MMT) was exfoliated using different ionic liquids ([C16MIM][Cl], [C16MIM][BF4], [C16MIM][PF6]), and silver nanoparticles (Ag NPs) were green-synthesized using hydroxypropyl cellulose (HPC). The HPC significantly enhanced the dispersion of MMT in the hydrogel. By introducing lauryl methacrylate (LMA), a hydrophobic associative network was constructed in PAM/LMA/HPC/MMT@ILs&Ag NPs hydrogel. This hydrogel demonstrated outstanding mechanical properties, with a stress of 833.21 kPa, strain of 3300 %, and toughness of 14.36 MJ/m3. It also exhibited excellent catalytic activity, with a rate constant of 0.83 min-1 for 4-nitrophenol degradation at 28 °C. The effects of temperature and catalyst concentration on the catalytic reaction were systematically investigated. This study presents a simple green synthesis approach for Ag NPs using HPC, achieving superior mechanical performance and stable MMT dispersion in aqueous solutions.


Subject(s)
Bentonite , Cellulose , Hydrogels , Ionic Liquids , Metal Nanoparticles , Silver , Water Pollutants, Chemical , Cellulose/chemistry , Cellulose/analogs & derivatives , Ionic Liquids/chemistry , Catalysis , Bentonite/chemistry , Hydrogels/chemistry , Water Pollutants, Chemical/chemistry , Silver/chemistry , Metal Nanoparticles/chemistry , Anions/chemistry , Nitrophenols/chemistry , Green Chemistry Technology , Water Purification/methods
2.
Int J Biol Macromol ; 271(Pt 1): 132699, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38824103

ABSTRACT

Conductive hydrogels, as novel flexible biosensors, have demonstrated significant potential in areas such as soft robotics, electronic devices, and wearable technology. Graphene is a promising conductive material, but its dispersibility in aqueous solutions exists difficulties. Here, we discover that untreated graphene, after exfoliation by different ionic liquids, can disperse well in aqueous solutions. We investigate the impact of four ionic liquids with varying alkyl chain lengths ([Bmim]Cl, [Omim]Cl, [Dmim]Cl, [Hmim]Cl) on the dispersibility of grapheme, and a dual physically cross-linked network hydrogel structure is designed using acrylamide (AM), acrylic acid (AA), methyl methacrylate octadecyl ester (SMA), ionic liquid@graphene (ILs@GN), and chitosan (CS). Notably, SMA, CS, AA and AM act as dynamic cross-linking points through hydrophobic interactions and hydrogen bonding, playing a crucial role in energy dissipation. The resulting hydrogel exhibits outstanding stretchability (2250 %), remarkable toughness (1.53 MJ/m3) in tensile deformation performance, high compressive strength (1.13 MPa), rapid electrical responsiveness (response time âˆ¼ 50 ms), high electrical conductivity (12.11 mS/cm), and excellent strain sensing capability (GF = 12.31, strain = 1000 %). These advantages make our composite hydrogel demonstrate high stability in extensive deformations, offering repeatability in pressure and strain and making it a promising candidate for multifunctional sensors and flexible electrodes.


Subject(s)
Chitosan , Electric Conductivity , Graphite , Hydrogels , Ionic Liquids , Chitosan/chemistry , Hydrogels/chemistry , Ionic Liquids/chemistry , Graphite/chemistry , Hydrophobic and Hydrophilic Interactions
3.
J Agric Food Chem ; 69(48): 14520-14529, 2021 Dec 08.
Article in English | MEDLINE | ID: mdl-34813299

ABSTRACT

Asarum heterotropoides extracts showed strong antibacterial activity against selected phytopathogenic bacteria. Bioguided isolation was conducted to obtain 11 phenanthrene derivatives (1-11), 4 phenylpropanoids (12-15), a flavonoid (16), and a steroid (17), including a new phenanthrene derivative (1). In vitro bioassay results showed that phenanthrene derivatives are the main active components of A. heterotropoides extracts. The new compound aristoloxazine C (1) was found to exhibit outstanding antibacterial activity against Ralstonia solanacearum, Xanthomonas oryzae, Erwinia carolovora, Pseudomonas syringae, and Xanthomonas axonopodis, with MIC values of 0.05, 2.5, 2.5, 5, and 6.25 µg/mL, respectively. These values were significantly higher than that of the positive control, streptomycin sulfate. Aristoloxazine C (1) also demonstrated an excellent control effect on tobacco bacterial wilt. Physiological and biochemical experiments combined with electron microscopy showed that the antibacterial activity of aristoloxazine C (1) was primarily related to the destruction of the bacterial cell wall structure. Thus, aristoloxazine C (1) may have the potential to be used as a template for the development of new bactericides or as a probe for the discovery of new antimicrobial targets.


Subject(s)
Asarum , Phenanthrenes , Ralstonia solanacearum , Xanthomonas , Anti-Bacterial Agents/pharmacology , Bacteria , Microbial Sensitivity Tests , Plant Diseases
4.
ACS Nano ; 13(12): 14540-14548, 2019 Dec 24.
Article in English | MEDLINE | ID: mdl-31742996

ABSTRACT

The practical deployment of lithium sulfur batteries demands stable cycling of high loading and dense sulfur cathodes under lean electrolyte conditions, which is very difficult to realize. We describe here a strategy of fabricating extremely dense sulfur cathodes, designed by integrating Mo6S8 nanoparticles as a multifunctional mediator with a Li-ion conducting binder and a high-performance Fe3O4@N-carbon sulfur host. The Mo6S8 nanoparticles have substantially faster Li-ion insertion kinetics compared with sulfur, and the produced LixMo6S8 particles have spontaneous redox reactivity with relevant polysulfide species (such as Li4Mo6S8 + Li2S4 ↔ Li3Mo6S8 + Li2S, ΔG = -84 kJ mol-1), which deliver a true redox catalytic sulfur conversion mechanism. In addition, LixMo6S8 particles strongly absorb polysulfide during battery cycling, which provides a quasi-solid sulfur conversion pathway and almost eliminated polysulfide dissolution. Such a pathway not only promotes growth of uniform Li2S that can be readily charged back with nearly no overpotential, but also mitigates the polysulfide-induced Li metal corrosion issue. The combination of these benefits enables stable and high capacity cycling of dense sulfur cathodes under a low electrolyte to sulfur ratio (4.2 µL mg-1), as demonstrated with cathodes with volumetric capacities of at least 1.3 Ah cm-3 and capacity retentions of ∼80% for 300 cycles. Furthermore, stable cycling of batteries under a practically relevant N/P ratio of 2.4 is also demonstrated.

5.
Biomed Res Int ; 2019: 6831520, 2019.
Article in English | MEDLINE | ID: mdl-31950049

ABSTRACT

Berberine (BBR) is an isoquinoline alkaloid isolated from various types of plants, including those from the Berberidaceae, Ranunculaceae, and Papaveraceae families. It has long been used in traditional Chinese medicine for treating diarrhea and gastrointestinal disorders. The medicinal properties of BBR include antimicrobial, anti-inflammatory, antioxidative, lipid-regulatory, and antidiabetic actions. Importantly, the efficacy of BBR against cancers has been assessed in several experimental studies and clinical trials. Gastrointestinal (GI) cancers are a group of the most prevalent cancers worldwide that are associated with high morbidity and mortality, and their associated mortality has been increasing over the years. Thus, GI cancers have become a burden to the patients and health care systems. This review summarizes the cellular and molecular mechanisms underlying the therapeutic effects of BBR and explores its potential preventive and therapeutic applications against GI cancers.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Berberine/therapeutic use , Gastrointestinal Neoplasms/drug therapy , Gastrointestinal Neoplasms/pathology , Humans , Medicine, Chinese Traditional
6.
Aging (Albany NY) ; 10(11): 3371-3381, 2018 11 29.
Article in English | MEDLINE | ID: mdl-30510148

ABSTRACT

BACKGROUND: Growing evidence shows that long noncoding RNAs (lncRNAs) play a crucial role in cancer progression. However, whether lncRNA CDKN2BAS is involved in human hepatocellular carcinoma (HCC) metastasis remains unclear. METHODS: Human lncRNA microarray analysis was performed to detect differential expression levels of lncRNAs in metastatic HCC tissues. Effects of CDKN2BAS on cell proliferation, migration, and apoptosis were determined by MTT assay, colony formation assay, migration assay, scratch assay, and flow cytometry. The xenograft experiment was used to confirm the effect of CDKN2BAS on HCC in vivo. qRT-PCR and Western blot were performed to determine the expression levels of mRNAs and proteins. Luciferase reporter assay was used to identify the specific target relationships. RESULTS: CDKN2BAS was remarkably up-regulated in metastatic HCC tissues compared with the adjacent non-tumor tissues. CDKN2BAS promotes HCC cell growth and migration in vitro and in vivo. Additionally, CDKN2BAS upregulated the expression of Rho GTPase activating protein 18 (ARHGAP18) by sponging microRNA-153-5p (miR-153-5p), and thus promoted HCC cell migration. Besides, CDKN2BAS downregulated the expression of Krüppel-like factor 13 (KLF13) and activated MEK-ERK1/2 signaling, thus reducing apoptosis in HCC cells. CONCLUSIONS: Our study revealed that lncRNA CDKN2BAS promotes HCC metastasis by regulating the miR-153-5p/ARHGAP18 signaling.


Subject(s)
Carcinoma, Hepatocellular/metabolism , GTPase-Activating Proteins/metabolism , Liver Neoplasms/metabolism , MicroRNAs/metabolism , RNA, Long Noncoding/metabolism , GTPase-Activating Proteins/genetics , Gene Expression Regulation, Neoplastic , Humans , Neoplasm Metastasis , RNA, Long Noncoding/genetics , Signal Transduction/physiology
7.
Psychiatry Res ; 270: 627-630, 2018 12.
Article in English | MEDLINE | ID: mdl-30384282

ABSTRACT

Glutamate is involved in mental disorders and nicotine addiction. The aim of the present study was to evaluate the relationship between cerebrospinal fluid (CSF) glutamate levels and mental status in Chinese heavy smokers. Participants comprised 41 non-smokers and 77 heavy smokers (n = 118). Cerebrospinal fluid was extracted and glutamate levels were measured. We recorded age, years of education, BMI, the Barratt impulsiveness scale (BIS), the Beck Depression Inventory (BDI) and the Self-Rating Anxiety Scale (SAS). BIS action scores, total scores and BDI scores were significantly different between the groups. Partial correlation analyses with age and education years as covariates found that CSF glutamate levels negatively correlated with BDI scores, but did not correlate with SAS scores in heavy smokers. No correlation was found between CSF glutamate levels and BDI or SAS scores in non-smokers. In conclusion, heavy smokers had more impulsivity had lower levels of CSF glutamate and higher BDI scores. CSF glutamate levels negatively correlated with BDI scores in heavy smokers.


Subject(s)
Depressive Disorder/cerebrospinal fluid , Glutamic Acid/cerebrospinal fluid , Psychiatric Status Rating Scales/statistics & numerical data , Smoking/cerebrospinal fluid , Adolescent , Adult , China , Correlation of Data , Depressive Disorder/diagnosis , Depressive Disorder/psychology , Humans , Male , Middle Aged , Psychometrics/statistics & numerical data , Reference Values , Smoking/adverse effects , Smoking/psychology , Young Adult
8.
Sci Rep ; 8(1): 12277, 2018 08 16.
Article in English | MEDLINE | ID: mdl-30115933

ABSTRACT

The cardiovascular health (CVH) metrics are closely related to the risk of stroke. Extracranial carotid artery stenosis (ECAS) represents an important risk factor for ischemic stroke. The present study aims to explore the longitudinal effect of the baseline CVH metrics on the development of ECAS. Totally 5,440 participants were randomly enrolled in the Asymptomatic Polyvascular Abnormalities Community study from 2010 to 2011. Information regarding the seven CVH metrics was collected at baseline. ECAS was assessed by performing carotid duplex sonography at baseline (2010-2011) and during the follow-up (2012-2013). Finally 3,487 subjects were included, and 976 participants developed ECAS during the 2-year follow-up. The optimum CVH status was associated with a 42% (95% confidence interval: 0.40-0.85) decreased risk of the incidence of ECAS after adjusting for age, sex, weight, education, income, alcohol use, waist-hip ratio, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, uric acid, homocysteine, and C-reactive protein. Ideal physical activity, total cholesterol and fasting blood glucose were independent protective factors of ECAS. In this cohort study, the ideal baseline CVH status was negatively associated with the occurrence of ECAS during the follow-up. This study provides practical insight for further developing effective screening strategies or implementing the best medical treatment.


Subject(s)
Cardiovascular Physiological Phenomena , Carotid Stenosis/epidemiology , Risk Reduction Behavior , Adult , Brain Ischemia/etiology , Brain Ischemia/prevention & control , Carotid Stenosis/complications , Cohort Studies , Female , Humans , Male , Middle Aged , Stroke/etiology , Stroke/prevention & control
9.
Sci Rep ; 7(1): 10893, 2017 09 07.
Article in English | MEDLINE | ID: mdl-28883616

ABSTRACT

The association between insomnia and metabolic syndrome remains unclear, especially among different-aged groups. A cross-sectional study with 8017 participants was performed to identify whether insomnia was associated with metabolic syndrome or not. Demographic characteristics, lifestyles and other risk factors were collected using a predesigned, semi-structured, self-administered questionnaire, and physical examinations were conducted by certificated community physicians. Insomnia was not independently associated with metabolic syndrome across all subjects; however, the association between insomnia and metabolic syndrome was statistically significant in the male group (odds ratio (OR): 1.35, 95% confidence interval (CI): 1.02-1.77) and the middle-aged group (OR: 1.40, 95% CI: 1.09-1.79) but not in the female group, the young adult group or the older group. Analyses of the individual components of metabolic syndrome revealed that insomnia was independently associated with raised blood pressure (OR: 1.24, 95% CI: 1.05-1.43) and low high-density lipoprotein cholesterol (HDL-c) (OR: 1.16, 95% CI: 1.01-1.33). Insomnia was also independently associated with the severity of metabolic abnormalities (OR: 1.17, 95% CI: 1.03-1.32). This study demonstrates an independent association between insomnia and metabolic syndrome in males and middle-aged participants, which suggests that treatment for insomnia will contribute to the prevention of metabolic syndrome in males and the middle-aged population.


Subject(s)
Metabolic Syndrome/complications , Metabolic Syndrome/epidemiology , Sleep Initiation and Maintenance Disorders/complications , Sleep Initiation and Maintenance Disorders/epidemiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Asian People , Cross-Sectional Studies , Ethnicity , Female , Humans , Male , Middle Aged , Physical Examination , Risk Factors , Sex Factors , Surveys and Questionnaires , Young Adult
10.
Nano Lett ; 17(5): 3061-3067, 2017 05 10.
Article in English | MEDLINE | ID: mdl-28448154

ABSTRACT

Li-S batteries have been extensively studied using rigid carbon as the host for sulfur encapsulation, but improving the properties with a reduced electrolyte amount remains a significant challenge. This is critical for achieving high energy density. Here, we developed a soft PEO10LiTFSI polymer swellable gel as a nanoscale reservoir to trap the polysulfides under lean electrolyte conditions. The PEO10LiTFSI gel immobilizes the electrolyte and confines polysulfides within the ion conducting phase. The Li-S cell with a much lower electrolyte to sulfur ratio (E/S) of 4 gE/gS (3.3 mLE/gS) could deliver a capacity of 1200 mA h/g, 4.6 mA h/cm2, and good cycle life. The accumulation of polysulfide reduction products, such as Li2S, on the cathode, is identified as the potential mechanism for capacity fading under lean electrolyte conditions.

11.
ACS Appl Mater Interfaces ; 9(5): 4290-4295, 2017 Feb 08.
Article in English | MEDLINE | ID: mdl-27367455

ABSTRACT

In rechargeable Li-S batteries, the uncontrollable passivation of electrodes by highly insulating Li2S limits sulfur utilization, increases polarization, and decreases cycling stability. Dissolving Li2S in organic electrolyte is a facile solution to maintain the active reaction interface between electrolyte and sulfur cathode, and thus address the above issues. Herein, ammonium salts are demonstrated as effective additives to promote the dissolution of Li2S to 1.25 M in DMSO solvent at room temperature. NMR measurements show that the strong hydrogen binding effect of N-H groups plays a critical role in dissolving Li2S by forming complex ligands with S2- anions coupled with the solvent's solvating surrounding. Ammonium additives in electrolyte can also significantly improve the oxidation kinetics of Li2S, and therefore enable the direct use of Li2S as cathode material in Li-S battery system in the future. This provides a new approach to manage the solubility of lithium sulfides through cation coordination with sulfide anion.

12.
Int J Clin Exp Pathol ; 10(7): 7384-7389, 2017.
Article in English | MEDLINE | ID: mdl-31966580

ABSTRACT

Mutations in mitochondrial DNA (mtDNA) were found to be associated with hypertension. We reported here clinical, genetic and molecular characterization of a Han Chinese family with maternally inherited hypertension. Most strikingly, this family exhibited a high penetrance of hypertension. Sequence analysis of the entire mitochondrial genome showed the presence of the well-known T4363C mutation in tRNAGln, as well as the ND1 T3394C mutation, and a set of polymorphisms belonging to human mitochondrial haplogroup M7b. Of these, the T4363C mutation was localized at the highly conserved nucleotide in the anticodon stem of tRNAGln (position 38), may result the failure in tRNA metabolism. Moreover, the homoplasmic ND1 T3394C mutation, which had been reported to be associated with Leber's hereditary optic neuropathy (LHON), was regarded as a pathogenic mutation associated with mitochondrial diseases. Thus, the combination of ND1 T3394C and tRNAGln T4363C mutations may contribute to the high penetrance and expressivity of hypertension in this Chinese family.

13.
ACS Appl Mater Interfaces ; 8(22): 13673-7, 2016 Jun 08.
Article in English | MEDLINE | ID: mdl-27182714

ABSTRACT

This work describes the synthesis of Chevrel phase Mo6S8 nanocubes and its application as the anode material for rechargeable Zn-ion batteries. Mo6S8 can host Zn(2+) ions reversibly in both aqueous and nonaqueous electrolytes with specific capacities around 90 mAh/g, and exhibited remarkable intercalation kinetics and cyclic stability. In addition, we assembled full cells by integrating Mo6S8 anodes with zinc-polyiodide (I(-)/I3(-))-based catholytes, and demonstrated that such full cells were also able to deliver outstanding rate performance and cyclic stability. This first demonstration of a zinc-intercalating anode could inspire the design of advanced Zn-ion batteries.

14.
ACS Appl Mater Interfaces ; 6(17): 15542-9, 2014 Sep 10.
Article in English | MEDLINE | ID: mdl-25100666

ABSTRACT

Lithium oxalyldifluoroborate (LiODFB) has been investigated as an organic electrolyte additive to improve the cycling performance of Li-S batteries. Cell test results demonstrate that an appropriate amount of LiODFB added into the electrolyte leads to a high Coulombic efficiency. Analyses by energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and the density functional theory showed that LiODFB promotes the formation of a LiF-rich passivation layer on the lithium metal surface, which not only blocks the polysulfide shuttle, but also stabilizes the lithium surface.

15.
Nano Lett ; 13(10): 4642-9, 2013 Oct 09.
Article in English | MEDLINE | ID: mdl-24032420

ABSTRACT

A multiwalled carbon nanotube/sulfur (MWCNT@S) composite with core-shell structure was successfully embedded into the interlay galleries of graphene sheets (GS) through a facile two-step assembly process. Scanning and transmission electron microscopy images reveal a 3D hierarchical sandwich-type architecture of the composite GS-MWCNT@S. The thickness of the S layer on the MWCNTs is ~20 nm. Raman spectroscopy, X-ray diffraction, thermogravimetric analysis, and energy-dispersive X-ray analysis confirm that the sulfur in the composite is highly crystalline with a mass loading up to 70% of the composite. This composite is evaluated as a cathode material for Li/S batteries. The GS-MWCNT@S composite exhibits a high initial capacity of 1396 mAh/g at a current density of 0.2C (1C = 1672 mA/g), corresponding to 83% usage of the sulfur active material. Much improved cycling stability and rate capability are achieved for the GS-MWCNT@S composite cathode compared with the composite lacking GS or MWCNT. The superior electrochemical performance of the GS-MWCNT@S composite is mainly attributed to the synergistic effects of GS and MWCNTs, which provide a 3D conductive network for electron transfer, open channels for ion diffusion, strong confinement of soluble polysulfides, and effective buffer for volume expansion of the S cathode during discharge.


Subject(s)
Electric Power Supplies , Graphite/chemistry , Lithium/chemistry , Ions , Nanotubes, Carbon/chemistry , Sulfur/chemistry , X-Ray Diffraction
16.
ChemSusChem ; 6(8): 1438-44, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23788469

ABSTRACT

Polypyrrole-polyethylene glycol (PPy/PEG)-modified sulfur/aligned carbon nanotubes (PPy/PEG-S/A-CNTs) were synthesized by using an in situ polymerization method. The ratio of PPy to PEG equaled 31.7:1 after polymerization, and the PEG served as a cation dopant in the polymerization and electrochemical reactions. Elemental analysis, FTIR, Raman spectroscopy, XRD, and electrochemical methods were performed to measure the physicochemical properties of the composite. Elemental analysis demonstrated that the sulfur, PPy, PEG, A-CNT, and chloride content in the synthesized material was 64.6%, 22.1%, 0.7%, 12.1%, and 0.5%, respectively. The thickness of the polymer shell was about 15-25 nm, and FTIR confirmed the successful PPy/PEG synthesis. The cathode exhibited a high initial specific capacity of 1355 mAh g(-1) , and a sulfur usage of 81.1%. The reversible capacity of 924 mAh g(-1) was obtained after 100 cycles, showing a remarkably improved cyclability compared to equivalent systems without PEG doping and without any coatings. PPy/PEG provided an effective electronically conductive network and a stable interface structure for the cathode. Rate performance of the PPy/PEG- S/A-CNT composite was more than double that of the unmodified S/A-CNTs. Remarkably, the battery could work at a very high current density of 8 A g(-1) and reached an initial capacity of 542 mAh g(-1) ; it also retained a capacity of 480 mAh g(-1) after 100 cycles. The addition of PEG as a dopant in the PPy shell contributed to this prominent rate improvement. Lithium ions and electrons were available everywhere on the surfaces of the particles, and thus could greatly improve the electrochemical reaction; PEG is a well-known solvent for lithium salts and a very good lithium-ion catcher.


Subject(s)
Electric Power Supplies , Lithium/chemistry , Polyethylene Glycols/chemistry , Polymers/chemistry , Pyrroles/chemistry , Sulfur/chemistry , Electric Conductivity , Electrodes , Nanotubes, Carbon/chemistry
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