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1.
Int J Biol Macromol ; 267(Pt 1): 131512, 2024 May.
Article in English | MEDLINE | ID: mdl-38608972

ABSTRACT

Two-dimensional (2D) transition metal carbides (Ti3C2Tx MXene) have gained significant attention for their potential in constructing diverse functional materials, However, MXene is easily oxidized and weakly bound to the cellulose matrix, which pose challenges in developing MXene-decorated non-woven fabric with strong bonding and stable thermal management properties. Herein, we successfully prepared deep eutectic supramolecular polymer (DESP) functionalized MXene to address these issues. MXene can be wrapped with DESP to be insulated from water and protected from being oxidized. Subsequently, we achieved an efficient in-situ deposition of DESP-functionalized MXene onto fibers through a combination of dip coating and photopolymerization technique. The resulting nonwoven fabric (CNs-DESP@M) exhibited excellent photothermal conversion properties along with rapid thermal response and functional stability. Interestingly, the interface bonding between MXene and the fiber surface was significantly enhanced due to the abundant pyrogallol groups in DESP, resulting in the composite textile exhibiting commendable mechanical properties (2.68 MPa). Moreover, the as-prepared textile demonstrates outstanding bactericidal efficacy against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The multifunctional textile, created through a facile and efficient approach, demonstrates remarkable potential for applications in smart textiles, catering to the diverse needs of individuals in the future.


Subject(s)
Anti-Bacterial Agents , Cellulose , Escherichia coli , Polymers , Staphylococcus aureus , Textiles , Cellulose/chemistry , Cellulose/pharmacology , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Polymers/chemistry , Mechanical Phenomena , Temperature , Microbial Viability/drug effects
2.
Int J Biol Macromol ; 269(Pt 2): 131904, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38688337

ABSTRACT

Catalytic reduction of p-nitrophenol is usually carried out using transition metal nanoparticles such as gold, palladium, silver, and copper, especially palladium nanoparticles (Pd NPs), which are characterized by fast reaction rate, high turnover frequency, good selectivity, and high yield. However, the aggregation and precipitation of the metals lead to the decomposition of the catalyst, which results in a significant reduction of the catalytic activity. Therefore, the preparation of homogeneous stabilized palladium nanoparticles catalysts has been widely studied. Stabilized palladium nanoparticles mainly use synthetic polymers. Cellulose microspheres, as a natural polymer material with low-cost and porous fiber network structure, are excellent carriers for stabilizing metal nanoparticles. Cellulose microspheres impregnated with palladium metal nanoparticles were carbonized to have a larger specific surface area and highly dispersed palladium nanoparticles, which exhibited excellent catalytic activity in the catalytic reduction of p-nitrophenol. In this work, the cellulose carbon-based microspheres palladium (Pd@CCM) catalysts were designed and characterized by SEM, TEM, EDS, XRD, FTIR, XPS, TGA, BET, and so on. Furthermore, the catalytic performance of Pd@CCM catalysts was investigated via p-nitrophenol reduction, which showed high catalytic activity. This catalyst also exhibited excellent catalytic performance in the Suzuki-Miyaura coupling reaction. Linking aromatic monomer and benzene through Suzuki-Miyaura coupling was presented as an effective route to obtaining biaryls, and the synthesis method is low-cost and simple. In addition, Pd@CCM showed desirable recyclability while maintaining its catalytic activity even after five recycles. This work is highly suggestive of the design and application of the heterogeneous catalyst.


Subject(s)
Carbon , Cellulose , Metal Nanoparticles , Microspheres , Nitrophenols , Palladium , Palladium/chemistry , Catalysis , Nitrophenols/chemistry , Metal Nanoparticles/chemistry , Cellulose/chemistry , Carbon/chemistry , Oxidation-Reduction
3.
Sci Adv ; 8(23): eabn3509, 2022 06 10.
Article in English | MEDLINE | ID: mdl-35687692

ABSTRACT

Most genome-wide association study (GWAS)-identified breast cancer-associated causal variants remain uncharacterized. To provide a framework of understanding GWAS-identified variants to function, we performed a comprehensive study of noncoding regulatory variants at the NTN4 locus (12q22) and NTN4 gene in breast cancer etiology. We find that rs11836367 is the more likely causal variant, disrupting enhancer activity in both enhancer reporter assays and endogenous genome editing experiments. The protective T allele of rs11837367 increases the binding of GATA3 to the distal enhancer and up-regulates NTN4 expression. In addition, we demonstrate that loss of NTN4 gene in mice leads to tumor earlier onset, progression, and metastasis. We discover that NTN4, as a tumor suppressor, can attenuate the Wnt signaling pathway by directly binding to Wnt ligands. Our findings bridge the gaps among breast cancer-associated single-nucleotide polymorphisms, transcriptional regulation of NTN4, and breast cancer biology, which provides previously unidentified insights into breast cancer prediction and prevention.


Subject(s)
Genome-Wide Association Study , Neoplasms , Netrins/metabolism , Alleles , Animals , Genetic Predisposition to Disease , Mice , Neoplasms/genetics , Netrins/genetics , Polymorphism, Single Nucleotide , Wnt Signaling Pathway/genetics
4.
Cancer Sci ; 113(7): 2457-2471, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35441763

ABSTRACT

Our previous works have indicated that extracellular ATP is an important prometastasis factor. However, the molecular mechanism involved needs to be further studied. We demonstrated that extracellular ATP treatment could upregulate the expression of connective tissue growth factor (CTGF) in both triple-negative breast cancer (TNBC) cells and endothelial cells (ECs). Extracellular ATP stimulated the migration of TNBC cells and ECs, and angiogenesis of ECs via the P2Y2--YAP-CTGF axis. Furthermore, we demonstrated that adenosine triphosphate (ATP) stimulated TNBC cell adhesion to ECs and transmigration through the EC layer via CTGF by upregulation of integrin ß1 on TNBC cells and VCAM-1 on ECs. Both apyrase (ATP-diphosphohydrolase) and CTGF shRNA treatments could inhibit the metastasis of inoculated tumors to lung and liver in a mouse model, and these treated tumors had fewer blood vessels. Collectively, our data indicated that extracellular ATP promotes tumor angiogenesis and the interactions between TNBC cells and ECs through upregulation of CTGF, thereby stimulating TNBC metastasis. The pleiotropic effects of ATP in angiogenesis and cell adhesion suggest that extracellular ATP or CTGF could be an effective target for TNBC therapy.


Subject(s)
Adenosine Triphosphate , Connective Tissue Growth Factor , Triple Negative Breast Neoplasms , Adenosine Triphosphate/metabolism , Animals , Connective Tissue Growth Factor/genetics , Connective Tissue Growth Factor/metabolism , Endothelial Cells/metabolism , Humans , Mice , Neovascularization, Pathologic/metabolism , Triple Negative Breast Neoplasms/metabolism , Up-Regulation
5.
Int J Biol Macromol ; 166: 1419-1428, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33161082

ABSTRACT

Dyeing industry highly contributes to environmental pollution and this needs to be addressed on priority. Pd NPs/CMs, a highly efficient and reusable catalyst for methylene blue (MB) decolorization, were fabricated by in-situ reduction method based on the cellulose microspheres (CMs). Pd NPs/CMs were characterized for the structure and catalytic performance by spectroscopic techniques such as SEM, EDS, XRD, IR, XPS, porosity, zeta potential, MS, and UV-visible spectroscopy, which all demonstrated that Pd NPs were distributed on the cellulose microspheres uniformly and exhibited excellent catalytic performances to decolorize a model organic dye MB in the presence of NaBH4 with catalytic efficiency higher than 99.8%. More importantly, Pd NPs/CMs were proven to show excellent reusability for at least five cycles. Decolorization mechanism of MB, via the destruction of the chromophores (CN and S) of MB, was established with the help of MS combined with IR and XPS. Blank experiments using pure cellulose microspheres were carried out simultaneously to estimate the level of catalytic capacity achieved to Pd NPs/CMs. These materials proved themselves having great potential in large scale applications to treat dye-containing wastewater.


Subject(s)
Cellulose/analogs & derivatives , Metal Nanoparticles/chemistry , Methylene Blue/chemistry , Microspheres , Palladium/chemistry , Catalysis
6.
Huan Jing Ke Xue ; 41(6): 2746-2753, 2020 Jun 08.
Article in Chinese | MEDLINE | ID: mdl-32608790

ABSTRACT

Fenton reaction is a traditional method for the treatment of dye-containing wastewater. However, this process should be performed in a narrow pH range and requires large amounts of ferrous salt input, limiting its application. In this work, a robust iron complex bearing a cross-bridge cyclam ligand (Fe-cyclam) was successfully prepared. This complex could effectively activate H2O2 to degrade rhodamine B at a pH range of 2-7. The Fe-cyclam/H2O2 system was more effective in the degradation of rhodamine B than the Fenton reaction, when the input [Fe] was lower than 50 µmol·L-1. Moreover, in addition to rhodamine B, the Fe-cyclam/H2O2 system was also capable of degrading dyes such as acid red 88, acid orange II, reactive red 24, and neutral red. This system was more efficient in the degradation of azo dyes than that of triphenylmethane dyes. The removal of rhodamine B remained higher than 90% in three cycle experiments, indicating the excellent stability of Fe-cyclam. The quenching experiments proved that the degradation of rhodamine B by Fe-cyclam/H2O2 was a free-radical-control process. Meanwhile, the electron paramagnetic resonance captured the signals of high valent FeV-oxo species, indicating that FeV-oxo possibly mediated the degradation of rhodamine B in the Fe-cyclam/H2O2 system. This work proves the potential application of Fe-cyclam/H2O2 in the degradation of dyes in a practical environment.

7.
Environ Sci Technol ; 54(17): 10820-10830, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32687335

ABSTRACT

Biosemiconductors are highly efficient systems for converting solar energy into chemical energy. However, the inevitable presence of reactive oxygen species (ROS) seriously deteriorates the biosemiconductor performance. This work successfully constructed a Mn3O4 nanozyme-coated biosemiconductor, Thiobacillus denitrificans-cadmium sulfide (T. denitrificans-CdS@Mn3O4), via a simple, fast, and economic method. After Mn3O4 coating, the ROS were greatly eliminated; the concentrations of hydroxyl radicals, superoxide radicals, and hydrogen peroxide were reduced by 90%, 77.6%, and 26%, respectively, during photoelectrotrophic denitrification (PEDeN). T. denitrificans-CdS@Mn3O4 showed a 28% higher rate of nitrate reduction and 78% lower emission of nitrous oxide (at 68 h) than that of T. denitrificans-CdS. Moreover, the Mn3O4 coating effectively maintained the microbial viability and photochemical activity of CdS in the biosemiconductor. Importantly, no lag period was observed during PEDeN, suggesting that the Mn3O4 coating does not affect the metabolism of T. denitrificans-CdS. Immediate decomposition and physical separation are the two possible ways to protect a biosemiconductor from ROS damage by Mn3O4. This study provides a simple method for protecting biosemiconductors from the toxicity of inevitably generated ROS and will help develop more stable and efficient biosemiconductors in the future.


Subject(s)
Thiobacillus , Denitrification , Hydrogen Peroxide , Nitrates , Nitrous Oxide
8.
JCI Insight ; 5(8)2020 04 23.
Article in English | MEDLINE | ID: mdl-32213710

ABSTRACT

Monocyte-derived DCs (moDCs) have been implicated in the pathogenesis of autoimmunity, but the molecular pathways determining the differentiation potential of these cells remain unclear. Here, we report that microRNA-148a (miR-148a) serves as a critical regulator for moDC differentiation. First, miR-148a deficiency impaired the moDC development in vitro and in vivo. A mechanism study showed that MAFB, a transcription factor that hampers moDC differentiation, was a direct target of miR-148a. In addition, a promoter study identified that miR-148a could be transcriptionally induced by PU.1, which is crucial for moDC generation. miR-148a ablation eliminated the inhibition of PU.1 on MAFB. Furthermore, we found that miR-148a increased in monocytes from patients with psoriasis, and miR-148a deficiency or intradermal injection of antagomir-148a immensely alleviated the development of psoriasis-like symptoms in a psoriasis-like mouse model. Therefore, these results identify a pivotal role for the PU.1-miR-148a-MAFB circuit in moDC differentiation and suggest a potential therapeutic avenue for autoimmunity.


Subject(s)
Autoimmunity/immunology , Dendritic Cells/immunology , MafB Transcription Factor/immunology , MicroRNAs/immunology , Animals , Autoimmunity/genetics , Cell Differentiation/genetics , Cell Differentiation/immunology , Humans , Inflammation/genetics , Inflammation/immunology , MafB Transcription Factor/genetics , Mice , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/immunology , Psoriasis/genetics , Psoriasis/immunology , Trans-Activators/genetics , Trans-Activators/immunology
9.
J Hazard Mater ; 394: 122560, 2020 07 15.
Article in English | MEDLINE | ID: mdl-32220704

ABSTRACT

The high dosage of catalyst requirement and weak anti-interference ability limit current heterogeneous manganese (Mn) catalyst/peroxymonosulfate (PMS) systems to remediate the organic polluted wastewater in complicated environment. Inspired by the concept of atom economy, herein, a homogenous manganese complex bearing a cross-bridged cyclam ligand Mn(cbc)Cl2 (MnL, L = cbc = 4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane)) is capable of activating PMS for reactive brilliant red K-2BP (RBR K-2BP) degradation. The dosage of MnL for PMS activation was low, in a range of 0.38∼3.8 mg/L. The quenching experiments demonstrated that the degradation was a nonradical-controlled process. Using methyl phenyl sulfoxide (PMSO) as a probe, the dominated degradation process of substrate was via an oxygen transfer pathway. Moreover, a high-valent Mn-oxo [(O)MnVLCl2]+ was directly detected using electrospray ionization mass spectrometry (ESI/MS). This system showed excellent anti-interference ability to both anions and humic acid, a typical natural organic matter. The atom economy, represented by an index ((mg pollutant)/h/(g catalyst)), showed that MnL 22737 in PMS activation was much higher than those of Mn-based heterogeneous catalytic systems 67∼960 and was only behind that of iron-tetraamidomacrocyclic ligand Fe-TAML 59139. This work provides insights into designing an atom-economic Mn-based PMS activator for efficient treatments for organic pollutants in a complicated environment.

10.
Int J Biol Macromol ; 149: 93-100, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-31931058

ABSTRACT

Amoxicillin in the municipal water system needs to be removed due to the toxicity towards creatures. In this work, Mg-Al LDH/cellulose nanocomposite beads (LDH@CB) were synthesized by an in situ coprecipitation procedure and were used as novel adsorbents for amoxicillin removal in the aqueous phase. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), The specific surface area test (BET), scanning electron microscopy (SEM), ζ potential, X-ray electron energy (XPS) were employed to confirm the success load of LDH onto CB. The large specific surface area (76.46 m2 g-1), high water content (92.05%) and high porosity (94.75%) of LDH@CB made the adsorbent suitable in water treatment. The adsorption process was kinetically fitted with the pseudo second-order kinetic model while isothermally fitted with the Freundlich isotherm model. It was found that the maximum adsorption capacity of LDH@CB qm was 138.3 mg g-1. Meanwhile, the results from XPS and ζ potentials revealed the AMX removal mechanism: Under natural pH conditions, AMX was negatively charged and LDH@CB was positively charged, the contaminant and the adsorbent were linked by electrostatic interaction through OCO⋯M (Mg/Al). These results showed that the adsorbent design method had a wide application prospect in the water purification field.


Subject(s)
Amoxicillin/chemistry , Cellulose/chemistry , Chemical Precipitation , Nanocomposites/chemistry , Water Pollutants, Chemical/chemistry , Hydroxides/chemistry
11.
Carbohydr Polym ; 231: 115694, 2020 Mar 01.
Article in English | MEDLINE | ID: mdl-31888800

ABSTRACT

Cellulose-based photocatalysts of supported nanoparticles feature high photocatalytic activity but their facile construction and photocatalytic mechanism exploration are highly challenging. Herein, a simple structural design principle and synergistic properties of 3-layered porous cellulose-based membranes are used for catalytic degradation of Rhodamine B in an aqua system. The 3-layered Au-TiO2 cellulose membranes were fabricated through the tape method and the suction filtration process. The composite membranes with strong redox ability, high charge-separation efficiency, and wide absorption range could stimulate the solar-driven plasma evaporation of Au nanoparticles and the photocatalytic function of TiO2 nanoparticles simultaneously. As characterized by Scanning Electron Microscopy, well-defined Au nanoparticles with an average size of 18.24 ±â€¯3.17 nm were uniformly distributed on the TiO2-CM surface. Compared with TiO2-CM, TiO2-Au-CM showed better catalytic degradation of organic dye. This work demonstrated that a simple strategy design of Au-TiO2-CM could efficiently enhance the photocatalytic activity for the degradation of dyes in water.

12.
Front Pediatr ; 7: 342, 2019.
Article in English | MEDLINE | ID: mdl-31475124

ABSTRACT

Background: The efficacy of corticosteroids and intravenous immunoglobulin (IVIG) in pediatric myocarditis remains controversial. Objectives: The authors performed a meta-analysis to assess the therapeutic efficacy of corticosteroids and IVIG in children with myocarditis. Methods: We retrieved the trials on corticosteroids and IVIG therapy, respectively, in pediatric myocarditis from nine databases up to December 2018. Statistical analysis was performed using Review Manager 5.3. Results: Our analysis included 8 studies and 334 pediatric patients. The data demonstrated that children receiving corticosteroids showed no significant improvement on left ventricular ejection fraction (LVEF) from 1 to 8 month-follow-up (MD = 5.17%, 95% CI = -0.26% to 10.60%, P = 0.06), and no significant improvement in death or heart transplantation incidence at the end of follow-up (OR = 1.33, 95% CI = 0.27-6.70, P = 0.73). However, children receiving IVIG revealed a statistically remarkable increase in LVEF at a follow-up over the course of 6 months to 1 year (MD = 18.91%, 95% CI = 11.74-26.08%, P < 0.00001), and a decrease in death or heart transplantation at the end of follow-up (OR = 0.31, 95% CI = 0.12-0.75, P = 0.01). Further comparisons showed that the mortality and heart transplantation rate of children with myocarditis treated with IVIG were significantly lower than those with corticosteroid therapy (t' = 11.336, P < 0.001). Conclusions: IVIG might be beneficial to improve LVEF and survival for myocarditis in children. However, the present evidence does not support corticosteroids as superior to conventional therapy in children with myocarditis. Further randomized controlled trials with a larger sample size are required.

13.
Environ Int ; 127: 353-360, 2019 06.
Article in English | MEDLINE | ID: mdl-30954721

ABSTRACT

N2O (Nitrous oxide, a booster oxidant in rockets) has attracted increasing interest as a means of enhancing energy production, and it can be produced by nitrate (NO3-) reduction in NO3--loading wastewater. However, conventional denitrification processes are often limited by the lack of bioavailable electron donors. In this study, we innovatively propose a self-photosensitized nonphototrophic Thiobacillus denitrificans (T. denitrificans-CdS) that is capable of NO3- reduction and N2O production driven by light. The system converted >72.1 ±â€¯1.1% of the NO3--N input to N2ON, and the ratio of N2O-N in gaseous products was >96.4 ±â€¯0.4%. The relative transcript abundance of the genes encoding the denitrifying proteins in T. denitrificans-CdS after irradiation was significantly upregulated. The photoexcited electrons acted as the dominant electron sources for NO3- reduction by T. denitrificans-CdS. This study provides the first proof of concept for sustainable and low-cost autotrophic denitrification to generate N2O driven by light. The findings also have strong implications for sustainable environmental management because the sunlight-triggered denitrification reaction driven by nonphototrophic microorganisms may widely occur in nature, particularly in a semiconductive mineral-enriched aqueous environment.


Subject(s)
Light , Nitrous Oxide/metabolism , Thiobacillus/physiology , Thiobacillus/radiation effects , Autotrophic Processes , Denitrification , Nitrates/metabolism
14.
IEEE Trans Haptics ; 11(4): 555-567, 2018.
Article in English | MEDLINE | ID: mdl-29993931

ABSTRACT

Touch screen technology supplies a new approach to interact with virtual environments. For haptic interaction on a touch screen, haptic devices that are capable of simultaneously conveying tactile and force information to users are highly desired for enhancing the sense of reality and immersion. To this end, a prototype haptic interface, called MH-Pen, was developed and fabricated to display the virtual interactive information through multi-mode haptic feedback. The MH-Pen is a self-contained system that provides vibrotactile feedback and precise force feedback by integrating three types of actuators. In this paper, MH-Pen's design, specifications, and working principle are described. Subsequently, to accurately display the interaction force, a hybrid actuator was designed by combining a piston-type magnetorheological (MR) actuator and a voice coil motor (VCM), and a closed-loop control scheme was built to manage the hybrid actuator. Finally, we objectively and subjectively evaluated the force feedback performance and the effect of multi-mode haptic display of the MH-Pen through physical measurements and psychophysical experiments of virtual surface stiffness display. The results show that improving the precision of force feedback and using multi-mode haptic display are both useful and necessary to enhance the sense of human-computer interaction realism.


Subject(s)
Equipment Design , Feedback, Sensory/physiology , Man-Machine Systems , Touch Perception/physiology , User-Computer Interface , Humans
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