Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 334
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Anal Chem ; 96(5): 1880-1889, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38253570

ABSTRACT

Compositional analysis of organic aerosols (OAs) at the molecular level has been a long-standing challenge in field and laboratory studies. In this work, we applied different extraction protocols to aerosol samples collected from the ambient atmosphere and biomass burning sources, followed by Orbitrap mass spectrometric analysis with a soft electrospray ionization source operating in both positive and negative ionization modes. To systematically map the distribution of mono- and dioxygenated aromatic compounds (referred to as aromatic CHO1 and CHO2 formulas) in OA, we developed a unique two-dimensional Kendrick mass defect (2D KMD) framework. Our analysis unveiled a total of (76, 64, 70) aromatic CHO1 formulas and (103, 110, 106) CHO2 formulas, corresponding to samples obtained from ambient air, rice straw burning, and sugarcane leaf burning, respectively. These results reveal a significant number of additional distinct formulas exclusively present in ambient samples, suggesting a significant chemical transformation of OAs in the atmosphere. The analytical approach can be further extended to incorporate multiple layers of 2D KMD, enabling systematic mapping of the unexplored chemical space for complex environmental samples.

2.
Phys Chem Chem Phys ; 26(19): 14244-14255, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38690716

ABSTRACT

In this work, PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 thin films with (002) preferred orientation were prepared using a pulsed laser deposition technique. The temperature dependence of resistivities ρI(T) was investigated under various applied DC currents. Colossal electroresistance (CER) effects were found in PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2. It was found that the positive CER values of PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 reach 3816% and 154% for I = 1.00 µA at 10 K, respectively. In addition, the ρI(T) cycle curves of PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 thin films showed a critical temperature similar to that of PbPdO2 (Tc = 260 K). Particularly, charge transfer between O1- and O2- was confirmed by in situ XPS. Additionally, based on first-principles calculations and internal electric field models, the CER and magnetic sources in PbPd0.9V0.1O2 and PbPd0.9Gd0.1O2 can be well explained. Finally, it was found that thin film samples doped with V and G ions exhibit weak localization (WL) and weak anti-localization (WAL) quantum transport properties. Ion doping leads to a transition from WAL to WL. The study results indicate that PbPdO2, one of the few oxide topological insulators, can exhibit novel quantum transport behavior after ion doping.

3.
J Thromb Thrombolysis ; 57(2): 194-203, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38180590

ABSTRACT

This meta-analysis compared the efficacy and safety of different antithrombotic regimens after left atrial appendage closure (LAAC). PubMed, Embase, Medline, Cochrane Library databases were systematically searched from their inception to March 2023. Patients were divided into short-term oral anticoagulation (OAC) group and antiplatelet therapy (APT) group. The incidence of events were performed using RevMan 5.4. The events including device-related thrombus (DRT), ischemic stroke/systemic embolization (SE), major bleeding, any bleeding, any major adverse event and all-cause mortality. Subgroup analysis were based on OAC alone or OAC plus single antiplatelet therapy (SAPT) in OAC group. Oral anticoagulants include warfarin and direct oral anticoagulant (DOAC). Fourteen studies with 35,166 patients were included. We found that the incidence of DRT (OR = 0.49, 95% CI 0.36-0.66, P<0.0001) and all-cause mortality (OR = 0.71, 95% CI 0.57-0.89, P = 0.002) were significantly lower in OAC group than APT group. However, there was no statistical differences in the incidence rates of ischemic stroke/SE (OR = 0.77, 95% CI 0.49-1.20, P = 0.25), major bleeding (OR = 0.84, 95% CI 0.55-1.27, P = 0.84), any bleeding (OR = 0.83, 95% CI 0.56-1.22, P = 0.34) and any major adverse event (OR = 0.56, 95% CI 0.30-1.03, P = 0.06) in the two groups. Subgroup analysis found that the incidence of DRT, all-cause mortality and any major adverse event in OAC monotherapy were lower than that in APT group (P<0.05), but not statistically different from other outcome. The incidence of DRT, all-cause mortality, any major adverse event and any bleeding in DOAC were significantly better than APT group (P<0.05). While warfarin only has better incidence of DRT than APT (P<0.05), there was no statistical difference between the two groups in other outcome (P>0.05). The incidence of DRT was significantly lower than APT group (P<0.05), major bleeding were higher, and the rest of the outcome did not show any statistically significant differences(P>0.05) when OAC plus SAPT. Based on the existing data, short-term OAC may be favored over APT for patients who undergo LAAC. DOAC monotherapy may be favored over warfarin monotherapy or OAC plus APT, when selecting anticoagulant therapies.


Subject(s)
Atrial Appendage , Atrial Fibrillation , Ischemic Stroke , Stroke , Humans , Warfarin/therapeutic use , Platelet Aggregation Inhibitors/therapeutic use , Left Atrial Appendage Closure , Atrial Fibrillation/drug therapy , Atrial Fibrillation/surgery , Atrial Fibrillation/epidemiology , Treatment Outcome , Anticoagulants/therapeutic use , Hemorrhage/chemically induced , Hemorrhage/epidemiology , Ischemic Stroke/complications , Stroke/etiology , Stroke/prevention & control , Stroke/epidemiology , Atrial Appendage/surgery
4.
J Sci Food Agric ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38828862

ABSTRACT

BACKGROUND: Gamma-aminobutyric acid (GABA) is an important neurotransmitter in the human body, with several negative emotions reported as being associated with GABA dysregulation. This study investigates the safety and modulatory effects of GABA-enriched milk, fermented by Streptococcus thermophilus GA8 and Lacticasebacillus rhamnosus HAO9, on the gut microbiota and neurotransmitter profiles in mice. RESULTS: Through rigorous culturing and fermentation processes, we achieved consistent GABA production in milk, with concentrations reaching 4.6 and 8.5 g L-1 for GA8-fermented and co-fermented milk, respectively, after 48 h. Using SPF male C57BL/6J mice, we administered either mono-culture or combined-culture milk treatments and monitored physiological impacts. The treatments did not affect mouse body weight but induced significant changes in gut microbiota composition. Beta diversity analysis revealed distinct microbial profiles between treatment groups, highlighting fermentation-specific microbial shifts, such as an increase in Verrucomicrobia for the GA8 group and a modulation in Saccharibacteria_genera_incertae_sedis for the GA8 + HAO9 group. Serum neurotransmitter levels were elevated in both treatment groups, with significant increases in l-glutamine, l-tryptophan and, notably, serotonin hydrochloride in the GA8 + HAO9 group. Correlation analysis identified a positive association between specific bacterial genera and neurotransmitter levels, suggesting a probiotic effect on neuroactive substances. CONCLUSION: These findings suggest that fermented milk has potential as a probiotic supplement for mood improvement and stress relief, highlighting its role in modulating the gut-brain axis. © 2024 Society of Chemical Industry.

5.
J Antimicrob Chemother ; 78(8): 2037-2051, 2023 08 02.
Article in English | MEDLINE | ID: mdl-37379498

ABSTRACT

OBJECTIVES: To describe the pharmacokinetics of vancomycin in a large Chinese paediatric cohort with varying degrees of renal function and ages and to develop practical dosing guidelines. PATIENTS AND METHODS: We conducted a retrospective population pharmacokinetic study using data from paediatric patients who received vancomycin between June 2013 and June 2022. A non-linear mixed-effect modelling approach with a one-compartment model structure was applied. Monte Carlo simulations were used to stimulate an optimal dosage regimen to achieve the target of AUC24/MIC between 400 and 650. RESULTS: We analysed a total of 673 paediatric patients and 1547 vancomycin serum concentrations. Covariate analysis revealed that physiological maturation, renal function, albumin and cardiothoracic surgery (CTS) significantly affected vancomycin pharmacokinetics. The typical clearance and volume of distribution, standardized to 70 kg, were 7.75 L/h (2.3% relative standard error, RSE) and 36.2 L (1.7% RSE), respectively. Based on the model, we proposed an optimal dosing regimen that considers the patient's age and estimate glomerular filtration rate (eGFR) to achieve a target AUC24/MIC for CTS and non-CTS patients. We also found that a loading dose of 20 mg/kg can help patients with an eGFR of <60 mL/min/1.73 m2 achieve the target AUC on the first day of treatment. CONCLUSIONS: We established vancomycin pharmacokinetic parameters in Chinese paediatric patients and proposed a dosing guideline integrating eGFR, age and CTS status, potentially improving clinical outcomes and reducing nephrotoxicity risk.


Subject(s)
Anti-Bacterial Agents , Vancomycin , Humans , Child , Retrospective Studies , East Asian People , Microbial Sensitivity Tests , Monte Carlo Method , Kidney/physiology
6.
Chemistry ; 29(16): e202203852, 2023 Mar 16.
Article in English | MEDLINE | ID: mdl-36562658

ABSTRACT

The reaction of nitronyl nitroxide biradical NITPhMeImbis [5-(2-methylimidazole)-1,3-bis(1-oxyl-3'-oxido-4',4',5',5'-tetramethyl-4,5-hydro-1H-imidazol-2-yl)-benzene] with Ln(hfac)3 ⋅ 2H2 O and Cu(hfac)2 (hfac=hexafluoroacetylacetonate), led to two series of 2p-3d-4f complexes, namely, nona-spin clusters, [Ln2 Cu3 (hfac)12 (NITPhMeImbis)2 ] (Ln=Gd 1, Dy 2), or one-dimensional chains [LnCu2 (hfac)7 (NITPhMeImbis)] (Ln=Y 3, Dy 4, Tb 5) depending on the temperature of the reaction. All five complexes contain a biradical-Ln unit in which the biradical chelates the LnIII ion by the means of one aminoxyl (i. e. NO) group of each NIT unit. For the discrete complexes, a Cu(hfac)2 links two biradical-Ln units via one of the remaining NO groups, while for the chain compounds, the two remaining NO groups of the biradical-Ln moiety are each coordinated to a Cu(hfac)2 unit to form a 1D coordination polymer. Moreover, a terminal Cu(hfac)2 unit is coordinated to the imidazole-N atom of the NITPhMeImbis ligand. Spin dynamics investigations evidenced the onset of slow relaxation of the magnetization for 2, whereas 4 and 5 exhibit a typical single-chain magnet behavior. This highlights the vital role of the 1D spin correlation in the blocking of the magnetization. These results illustrate that from the same basic building blocks, magnetic relaxation can be carefully modulated by structural adjustments.

7.
Langmuir ; 39(1): 177-191, 2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36562540

ABSTRACT

Pore size and pore connectivity control diffusion-based transport in mesopores, a crucial property governing the performance of heterogeneous catalysts. In many cases, transition-metal oxide catalyst materials are prepared from molecular precursors involving hydrothermal treatment followed by heat treatment. Here, we investigate the effects of such a hydrothermal aftertreatment step, using an aqueous ammonia solution, on the disordered mesopore network of CexZr1-x-y-zYyLazO2-δ mixed oxides. This procedure is a common synthesis step in the preparation of such ceria-based oxygen storage materials applied in three-way catalysis, employed to improve the materials' thermal stability. We perform state-of-the-art Ar-physisorption analysis, especially advanced hysteresis scanning, to paint a detailed picture of the alterations in mesopore space caused by the hydrothermal aftertreatment and subsequent aging at 1050 °C. Furthermore, we investigate the network characteristics by electron tomography in combination with suitable statistical analysis, enabling a consistent interpretation of the desorption scans (physisorption). The results indicate that the hydrothermal aftertreatment enhances the mesopore connectivity of the continuous 3D network by widening pores and especially necks, hence facilitating accessibility to the particles' internal surface area and the ability to better withstand high temperatures.

8.
Langmuir ; 39(49): 17664-17679, 2023 Dec 12.
Article in English | MEDLINE | ID: mdl-38011036

ABSTRACT

The connectivity and thermal stability of pores in heterogeneous, mesoporous metal oxide catalysts are key properties controlling their (long-term) efficacy. In this study, we investigate the influence of pH and temperature during a common hydrothermal aftertreatment step in the synthesis of mesoporous CexZr1-x-y-zYyLazO2-δ oxides obtained from molecular precursors via hydrothermal synthesis. This study has a strong focus on the methodological approach, elucidating whether and how even the smallest changes in morphology and connectivity may be unraveled and related to the underlying chemical processes to uncover key parameters for the ongoing improvement of material properties. Deep insights into the mesopore space were obtained by state-of-the-art physisorption (including hysteresis scanning), electron tomography, and small-angle X-ray scattering (SAXS) analysis. We also provide a simple tool to simulate SAXS curves from electron tomography data that allow direct comparison to experimentally obtained SAXS curves. Furthermore, the impact on surface-bound nitrate groups and the development during calcination were studied in detail by thermogravimetric analysis coupled with mass spectrometry. The key observations indicate a significant increase in thermal stability at temperatures as high as 1050 °C and improved mesopore accessibility with an increase in pH of the aftertreatment solution. The combined observations from the employed methods suggest a pH-dependent removal of surface-bound nitrate groups as well as a dissolution and reprecipitation-based fusing of the primary particles that constitute the mesopore skeleton. This transformation yields a mechanically and thermally stronger mesopore space with the capability to endure high temperatures.

9.
Cell Biol Toxicol ; 39(4): 1611-1626, 2023 08.
Article in English | MEDLINE | ID: mdl-35971034

ABSTRACT

N6-methyladenosine (m6A) mRNA methylation has been considered a gene modulatory mechanism involved in disease progression and carcinogenesis. Herein, we aimed to explore the specific mechanism of m6A mRNA methylation in endometrial cancer. RT-qPCR was implemented to test the clinical correlation between m6A methylation and endometrial cancer. Bioinformatics analysis was performed to screen the genes related to endometrial cancer, and SRAMP was utilized for the prediction of m6A targets. Western blot assay and MeRIP-qPCR experiments were conducted to verify the effect of m6A methylation on the candidate genes and the signaling pathways involved in the occurrence of endometrial cancer. m6A-seq, RT-qPCR, and polysome profiling were used to confirm the mechanisms of m6A methylation in modulating related genes and pathways. The levels of m6A methylation, METTL3, and IGFBP4 were reduced in tumor tissues of patients with endometrial cancer, and SRAMP analysis confirmed that IGFBP4 and PAPPA had m6A methylation sites. Reduced m6A methylation promoted endometrial cancer cell progression and tumor formation in vivo. m6A methylation of RNA in endometrial cancer cells directly modulated IGFBP4 and PAPPA expression. m6A methylation regulated the PAPPA/IGFBP4 axis, thereby influencing endometrial cancer through the NF-κB and ERK signaling pathways. Knockdown of PAPPA or overexpression of IGFBP4 in endometrial cancer cells partially reduced disease progression caused by reduced m6A methylation. This research suggests that m6A mRNA methylation modulates the ERK/NF-κB/AKT signaling pathway through the PAPPA/IGFBP4 axis to induce cell proliferation and tumor formation in endometrial cancer. 1. METTL3 expressed modestly and m6A methylation of IGFBP4 and PAPPA mRNAs decreased in endometrial cancer; 2. YTHDF1-mediated IGFBP4 translation was reduced in HEC-1-A and AN3CA cells, and YTHDF2-mediated PAPPA mRNA degradation was blunted but its protein expression increased; 3. Increased PAPPA and reduced IGFBP4 activated IGF1-induced ERK, AKT, and NF-κB pathways by binding IGFR, thereby promoting cancer cell malignancy.


Subject(s)
Endometrial Neoplasms , NF-kappa B , Female , Humans , Cell Proliferation/genetics , Disease Progression , Endometrial Neoplasms/genetics , Endometrial Neoplasms/pathology , Methylation , Methyltransferases/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction/genetics
10.
Sensors (Basel) ; 23(2)2023 Jan 11.
Article in English | MEDLINE | ID: mdl-36679639

ABSTRACT

The spatial-temporal prediction of traffic flow is very important for traffic management and planning. The most difficult challenges of traffic flow prediction are the temporal feature extraction and the spatial correlation extraction of nodes. Due to the complex spatial correlation between different roads and the dynamic trend of time patterns, traditional forecasting methods still have limitations in obtaining spatial-temporal correlation, which makes it difficult to extract more valid information. In order to improve the accuracy of the forecasting, this paper proposes a multi-scale temporal dual graph convolution network for traffic flow prediction (MD-GCN). Firstly, we propose a gated temporal convolution based on a channel attention and inception structure to extract multi-scale temporal dependence. Then, aiming at the complexity of the traffic spatial structure, we develop a dual graph convolution module including the graph sampling and aggregation submodule (GraphSAGE) and the mix-hop propagation graph convolution submodule (MGCN) to extract the local correlation and global correlation between neighbor nodes. Finally, extensive experiments are carried out on several public traffic datasets, and the experimental results show that our proposed algorithm outperforms the existing methods.


Subject(s)
Algorithms , Records , Reproduction
11.
Molecules ; 28(6)2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36985497

ABSTRACT

Employing the new nitronyl nitroxide biradical ligand biNIT-3Py-5-Ph (2-(5-phenyl-3-pyridyl)-bis(4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)), a 16-spin Cu-radical complex, [Cu8(biNIT-3Py-5-Ph)4(hfac)16] 1, and three 2p-3d-4f chain complexes, {[Ln(hfac)3][Cu(hfac)2]2(biNIT-3Py-5-Ph)2}n (LnⅢ= Gd 2, Tb 3, Dy 4; hfac = hexafluoroacetylacetonate), have been prepared and characterized. X-ray crystallographic analysis revealed in all derivatives a common cyclic [Cu-biNIT]2 secondary building unit in which two bi-NIT-3Py-5-Ph biradical ligands and two CuII ions are associated via the pyridine N atoms and NO units. For complex 1, two such units assemble with four additional CuII ions to form a discrete complex involving 16 S = 1/2 spin centers. For complexes 2-4, the [Cu-biNIT]2 units are linked by LnIII ions via NO groups in a 1D coordination polymer. Magnetic studies show that the coordination of the aminoxyl groups with Cu or Ln ions results in behaviors combining ferromagnetic and antiferromagnetic interactions. No slow magnetic relaxation behavior was observed for Tb and Dy derivatives.

12.
Anal Chem ; 94(24): 8633-8641, 2022 06 21.
Article in English | MEDLINE | ID: mdl-35675678

ABSTRACT

Antimicrobial susceptibility testing (AST) is an effective way to guide antibiotic selection. However, conventional culture-based phenotypic AST is time-consuming. The key point to shorten the test is to quantify the small change in the bacterial number after the antibiotic exposure. To achieve rapid AST, we proposed a combination of multiplexed PCR with barcoded pyrosequencing to significantly shorten the time for antibiotic exposure. First, bacteria exposed to each antibiotic were labeled with a unique barcode. Then, the pool of the barcoded products was amplified by PCR with a universal primer pair. Finally, barcodes in the amplicons were individually and quantitatively decoded by pyrosequencing. As pyrosequencing is able to discriminate as low as 5% variation in target concentrations, as short as 7.5 min was enough for cultivation to detect the susceptibility of Escherichia coli to an antibiotic. The barcodes enable more than six kinds of drugs or six kinds of concentrations of a drug to be tested at a time. The susceptibility of 6 antibiotics to 43 E. coli-positive samples from 482 clinical urine samples showed a consistency of 99.3% for drug-resistant samples and of 95.7% for drug-sensitive samples in comparison with the conventional method. In addition, the minimum inhibitory concentration (MIC) of 29 E. coli samples was successfully measured. The proposed AST is dye free (pyrosequencing), multiplexed (six antibiotics), fast (a half-working day for reporting the results), and able to detect the MIC, thus having a great potential for clinical use in quick antibiotic selection.


Subject(s)
Anti-Bacterial Agents , Escherichia coli Infections , Anti-Bacterial Agents/pharmacology , Bacteria , Escherichia coli/genetics , Escherichia coli Infections/drug therapy , Escherichia coli Infections/microbiology , High-Throughput Nucleotide Sequencing , Humans , Microbial Sensitivity Tests
13.
Anal Biochem ; 642: 114562, 2022 04 01.
Article in English | MEDLINE | ID: mdl-35093411

ABSTRACT

We propose a sensitive, selective, and rapid fluorescent assay for detecting resorcinol (RC) based on its specific chemical reaction with dopamine. Under alkaline condition, RC would react with dopamine to yield fluorescent azamonardine, which emits strong blue fluorescence and has a superior excitation wavelength at 416 nm and an emission wavelength at 461 nm. The azamonardine with a molecular weight of 258.1 confirmed by ICP-MS has a quantum yield of 71.3%. The reaction is completed within 1 min showing great potential for point-of-care testing. This assay showed high sensitivity and had a good relationship between fluorescent intensity at 461 nm and RC concentration (I461 = 106.4 + 93.6*CRC; R2 = 0.9904) over the range of 0-40 µM. More importantly, the assay showed a prominent anti-interference from various substances and even can distinguish RC from its isomers, o-dihydroxybenzene and p-dihydroxybenzene. Finally, our assay successfully quantified RC contents in wheat powder and hair dyes with high accuracy.


Subject(s)
Aza Compounds/chemistry , Dopamine/chemistry , Fluorescent Dyes/chemistry , Resorcinols/analysis , Hair Dyes/chemistry , Powders/chemistry , Triticum/chemistry
14.
Soft Matter ; 18(20): 3828-3844, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35506880

ABSTRACT

Supramolecular polymer gels (SPGs) are precisely designed gels brought together by noncovalent interactions to form three-dimensional network structures of polymers. SPGs combine the merits of supramolecular polymers and gels, such as stimuli-responsiveness, self-healing, and self-adaptation, which endows SPGs with potential application value in the fields of biomaterials, etc. Recently, much effort has been made to design new SPGs and related materials with high performance. Herein, we review the research endeavor and future directions of SPGs depending on the construction methods, topological structures, stimuli-responsiveness, and functionality. We hope that the review will provide reference values for the researchers working in supramolecular chemistry and gels.

15.
Infection ; 50(5): 1147-1154, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35182356

ABSTRACT

PURPOSE: The emergence of ceftazidime-avibactam (CZA) resistance in carbapenem-resistant Klebsiella pneumoniae (CRKP) has been increasingly reported in recent years. We aimed to identify the risk factors of CZA-resistant CRKP infection and assess clinical outcomes of the patients. METHODS: The study retrospectively analyzed the clinical and microbiological data of patients with CRKP infection to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis. RESULTS: A total of 103 patients with CRKP infection were enrolled in this study. Multivariate analysis showed previous renal replacement therapy (OR 3.966, 95% CI 1.301-12.090, P = 0.015) was an independent risk factor for CZA-resistant CRKP infection. The 28-day mortality was higher in patients infected with CZA-resistant CRKP (27.9%) than those with CZA-susceptible CRKP (7.1%) (P = 0.009). CZA-resistant CRKP infection (OR 20.308, 95% CI 1.461-282.293, P = 0.025), and mechanical ventilation (OR 14.950, 95% CI 1.034-216.212, P = 0.047) were independent predictors for 28-day mortality in patients with CRKP infection. Lower level of platelet count (OR 0.987, 95% CI 0.975-0.999, P = 0.032) on the day of CRKP infection onset was related to 28-day mortality. Kaplan-Meier curves showed that the CZA-resistant CRKP group had a shorter survival time than the CZA-susceptible CRKP group. CONCLUSION: The prevalence and mortality of CZA-resistant CRKP are still increasing. Strengthening the hospital infection control of renal replacement therapy and mechanical ventilation may help to prevent CZA-resistant CRKP.


Subject(s)
Cross Infection , Klebsiella Infections , Anti-Bacterial Agents/adverse effects , Azabicyclo Compounds , Carbapenems/pharmacology , Carbapenems/therapeutic use , Ceftazidime , Cross Infection/drug therapy , Cross Infection/epidemiology , Drug Combinations , Humans , Klebsiella Infections/drug therapy , Klebsiella Infections/epidemiology , Klebsiella Infections/microbiology , Klebsiella pneumoniae , Retrospective Studies , Risk Factors
16.
Nanotechnology ; 33(20)2022 Feb 21.
Article in English | MEDLINE | ID: mdl-35078160

ABSTRACT

After graphite oxide assisted the liquid phase shear exfoliation of attapulgite, the good dissociation and dispersion of attapulgite rod crystals are realized. Due to the spatial hindrance effect of attapulgite, which prevents the stacking of RGO sheets, the attapulgite-reduced graphene oxide three-dimensional porous hydrogel with abundant pore structure enables rapid transfer of electrolyte ions and exhibits good electrochemical performance and rate performance. The assembled flexible solid-state supercapacitor has a high operating voltage window and good flexibility and cycle stability. At a current density of 0.1 mA cm-2, it has an area specific capacitance of 127.33 mF cm-2. A series of solid-state supercapacitors can be used as the power supply for LED lights.

17.
Macromol Rapid Commun ; 43(14): e2100775, 2022 Jul.
Article in English | MEDLINE | ID: mdl-34882882

ABSTRACT

Supramolecular polymers not only possess many advantages of traditional polymers, but also have many unique characteristics. Supramolecular polymers can be constructed by self-assembly of various noncovalent interactions. Host-guest interaction, as one important type of noncovalent interactions, has been widely applied to construct supramolecular polymers. From the perspective of classification of the recognition system motifs, host-guest recognition motifs mainly include crown ether, cyclodextrin, calixarene, cucurbituril, and pillararene-based host-guest recognition pairs. Crown ethers, as the first-generation macrocyclic hosts, have played a very important part in the development of supramolecular chemistry. Due to the easy modification of crown ethers, various crown ether derivatives have been prepared by attaching some functional groups to the edges of crown ethers, which endowed them with some interesting properties and made them ideal candidates for the fabrication of supramolecular polymers. This review gives a review of the preparation of crown ether-based supramolecular polymers (CSPs) and summarizes crown ether-based recognition pairs, organization methods, topological structures, stimuli-responsiveness, and functional characteristics.


Subject(s)
Calixarenes , Crown Ethers , Cyclodextrins , Crown Ethers/chemistry , Cyclodextrins/chemistry , Molecular Structure , Polymers/chemistry
18.
Phys Chem Chem Phys ; 24(48): 29520-29527, 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36448469

ABSTRACT

Ferric oxide (Fe2O3) is an attractive anode material for lithium-ion batteries (LIBs) with a high theoretical capacity of 1005 mA h g-1. However, its practical application is greatly restrained by the rapid capacity fading caused by the large volume expansion upon lithiation. To address this issue, we have designed and synthesized a unique yolk-shell Fe2O3/N-doped carbon hybrid structure (YS-Fe2O3@NC) with rich oxygen vacancies for robust lithium storage. The obtained results show that YS-Fe2O3@NC delivers a high reversible capacity of 578 mA h g-1 after 300 cycles at a current density of 5 A g-1, about 11 times that (53.7 mA h g-1) of pristine Fe2O3. Furthermore, a high specific capacity of 300.5 mA h g-1 even at 10 A g-1 is achieved. The high reversible capacities, excellent rate capability and cycle stability of YS-Fe2O3@NC might be attributed to the elaborate yolk-shell nanoarchitecture. Moreover, electron percolation and a local built-in electric field induced by oxygen vacancies in the Fe2O3 matrix could also enhance the kinetics of Li+ insertion/deinsertion.

19.
Mol Ther ; 29(12): 3422-3435, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34371184

ABSTRACT

Mis-regulated epigenetic modifications in RNAs are associated with human cancers. The transfer RNAs (tRNAs) are the most heavily modified RNA species in cells; however, little is known about the functions of tRNA modifications in cancers. In this study, we uncovered that the expression levels of tRNA N7-methylguanosine (m7G) methyltransferase complex components methyltransferase-like 1 (METTL1) and WD repeat domain 4 (WDR4) are significantly elevated in human lung cancer samples and negatively associated with patient prognosis. Impaired m7G tRNA modification upon METTL1/WDR4 depletion resulted in decreased cell proliferation, colony formation, cell invasion, and impaired tumorigenic capacities of lung cancer cells in vitro and in vivo. Moreover, gain-of-function and mutagenesis experiments revealed that METTL1 promoted lung cancer growth and invasion through regulation of m7G tRNA modifications. Profiling of tRNA methylation and mRNA translation revealed that highly translated mRNAs have higher frequencies of m7G tRNA-decoded codons, and knockdown of METTL1 resulted in decreased translation of mRNAs with higher frequencies of m7G tRNA codons, suggesting that tRNA modifications and codon usage play an essential function in mRNA translation regulation. Our data uncovered novel insights on mRNA translation regulation through tRNA modifications and the corresponding mRNA codon compositions in lung cancer, providing a new molecular basis underlying lung cancer progression.


Subject(s)
Lung Neoplasms , Protein Biosynthesis , Codon Usage , GTP-Binding Proteins/genetics , GTP-Binding Proteins/metabolism , Humans , Lung Neoplasms/genetics , Methyltransferases/genetics , Methyltransferases/metabolism , RNA, Transfer/genetics
20.
Mediators Inflamm ; 2022: 3441357, 2022.
Article in English | MEDLINE | ID: mdl-36211988

ABSTRACT

Homoharringtonine (HHT) exhibits an anti-inflammatory activity. The potential protective effects and mechanisms of HHT on dextran sulfate sodium- (DSS-) induced colitis were investigated. DSS-induced colitis mice were intraperitoneally injected with HHT. Body weight, colon length, disease activity index (DAI), and histopathological change were examined. The relative contents of interleukin- (IL-) 1ß, tumor necrosis factor- (TNF-) α, IL-6, and the chemokine (C-C motif) ligand 2 (CCL2) in the colon tissues and HHT-treated RAW264.7 cells were detected with the enzyme-linked immunosorbent assay. In the meantime, the levels of p-p65 and p-IκBα were detected by Western blot. The proportion of macrophages (CD11b+F4/80+) in the colon tissues was detected by flow cytometry. HHT alleviated DSS-induced colitis with downregulated TNF-α, IL-1ß, IL-6, and CCL2 expression; reduced activation of nuclear factor-kappa B (NF-κB) signaling; and diminished proportion of recruited macrophages in colon tissues. It was further testified that HHT inhibited lipopolysaccharide-induced macrophage activation with reduced activation of NF-κB signaling. In addition, HHT inhibited the M1 polarization of both human and mouse macrophages, while HHT did not affect the differentiation of human CD4 T cells into Th17, Th1, or Treg cells and did not affect the proliferation and migration of human colon epithelial cells. In summary, HHT attenuates DSS-induced colitis by inhibiting macrophage-associated NF-κB activation and M1 polarization, which could be an option for the treatment of ulcerative colitis.


Subject(s)
Colitis, Ulcerative , Colitis , Animals , Anti-Inflammatory Agents/therapeutic use , Chemokine CCL2 , Colitis/chemically induced , Colitis/drug therapy , Colitis/pathology , Colitis, Ulcerative/drug therapy , Colon/metabolism , Dextran Sulfate/toxicity , Homoharringtonine/adverse effects , Humans , Interleukin-6 , Lipopolysaccharides , Mice , Mice, Inbred C57BL , NF-KappaB Inhibitor alpha , NF-kappa B/metabolism , Tumor Necrosis Factor-alpha/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL