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1.
Langmuir ; 40(23): 12017-12026, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804259

RESUMO

This work combined gold colloid probe atomic force microscopy (AFM) with a quartz crystal microbalance (QCM) to accurately quantify the molecular interactions of fluorine-free phosphonium-based ionic liquids (ILs) with gold electrode surfaces. First, the interactions of ILs with the gold electrode per unit area (FA', N/m2) were obtained via the force-distance curves measured by gold probe AFM. Second, a QCM was employed to detect the IL amount to acquire the equilibrium number of IL molecules adsorbed onto the gold electrode per unit area (NIL, Num/m2). Finally, the quantified molecular interactions of ILs with the gold electrode (F0, nN/Num) were estimated. F0 is closely related to the IL composition, in which the IL with the same anion but a longer phosphonium cation exhibits a stronger molecular interaction. The changes in the quantified interactions of gold with different ILs are consistent with the interactions predicted by the extended Derjaguin-Landau-Verwey-Overbeek theory, and the van der Waals interaction was identified as the major contribution of the overall interaction. The quantified molecular interaction is expected to enable the direct experimental-derived interaction parameters for molecular simulations and provide the virtual design of novel ILs for energy storage applications.

2.
Langmuir ; 40(17): 8886-8896, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38622867

RESUMO

Surface-enhanced Raman scattering (SERS) is a remarkably powerful analytical technique enabling trace-level detection of biological molecules. The interaction of a probe molecule with the SERS substrate shows important distinctions in the SERS spectra, providing inherent fingerprint information on the probe molecule. Herein, nonhalogenated phosphonium-based ionic liquids (ILs) containing cations with varying chain lengths were used as trace additives to amplify the interaction between the cytochrome c (Cyt c) and Zr-Al-Co-O (ZACO) nanotube arrays, strengthening the SERS signals. An increased enhancement factor (EF) by 2.5-41.2 times compared with the system without ILs was achieved. The improvement of the SERS sensitivity with the introduction of these ILs is strongly dependent on the cation chain length, in which the increasing magnitude of EF is more pronounced in the system with a longer alkyl chain length on the cation. Comparing the interaction forces measured by Cyt c-grafted atomic force microscopy (AFM) probes on ZACO substrates with those predicted by the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, the van der Waals forces became increasingly dominant as the chain length of the cations increased, associated with stronger Cyt c-ZACO XDLVO interaction forces. The major contributing component, van der Waals force, stems from the longer cation chains of the IL, which act as a bridge to connect Cyt c and the ZACO substrate, promoting the anchoring of the Cyt c molecules onto the substrate, thereby benefiting SERS enhancement.

3.
J Insect Sci ; 24(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38536151

RESUMO

The rape stem weevil (Ceutorhynchus asper Roel.) and its close relatives primarily breed on cruciferous plants and cause severe damage to rapeseed production. However, their genetic and molecular information is still scarce. Here, we generated mitogenomes for both C. asper and Ceutorhynchus albosuturalis. The lengths of the 2 mitochondrial genomes are 14,207 bp (C. asper) and 15,373 bp (C. albosuturalis), and both weevils exhibit identical numbers of protein-coding genes with the absence of trnI. A + T contents for both mitogenomes are high (80% and 79.9%, respectively). Haplotype and genetic distance analyses showed that the genetic differentiation of C. asper populations in northwestern China is low. Based on 5 datasets from mitogenomes, phylogenetic analyses with maximum-likelihood and Bayesian methods show that both species (C. asper and C. albosuturalis) fall in the CCCMS clade (Curculioninae, Conoderinae, Cossoninae, Molytinae, and Scolytinae) of Curculionidae and belong to clades H and I of the genus Ceutorhynchus, respectively. Larvae of the clade H weevils mainly are borers in petioles or stems of cruciferous plants, while larvae of the clade I weevils mainly inhabit the fruits of the same plants, suggesting that ecological niche specialization can play a critical role in the diversification of Ceutorhynchus species. This study generates baseline molecular and genetic information for future research of Ceutorhynchus-related taxa and provides insights into the phylogeny and evolution of Curculionidae.


Assuntos
Brassica rapa , Besouros , Genoma Mitocondrial , Gorgulhos , Animais , Filogenia , Teorema de Bayes , Larva
4.
Ann Surg Oncol ; 30(1): 363-372, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36151430

RESUMO

PURPOSE: This study was designed to establish risk classifications for early recurrence in hepatocellular carcinoma (HCC) patients with microvascular invasion (MVI) after hepatectomy. METHODS: The data of 563 HCC patients with MVI after hepatectomy from two hospitals were retrospectively reviewed. Kaplan-Meier curves and Cox proportional hazards regression models were used to analyse early recurrence. The risk classification for early recurrence was established by using classification and regression tree (CART) analysis and validated by using two independent validation cohorts from two hospitals. RESULTS: Multivariate analysis revealed that four indices, namely, infection of chronic viral hepatitis, MVI classification, tumour size, and serum alpha-fetoprotein (AFP), were independent prognostic factors for early recurrence in HCC patients with MVI. By CART analysis, MVI classification and serum AFP became the nodes of a decision tree and 3-stratification classifications that satisfactorily determined the risk of early recurrence were established. The area under the time-dependent receiver operating characteristic curve (AUC) values of the classification for early recurrence at 0.5, 1.0, and 2.0 years were 0.75, 0.73, and 0.71, respectively, which were all significantly higher than three common classic HCC stages (BCLC stage, Chinese stage, and TNM stage). The calibration curves showed good agreement between predictions by classification for early recurrence and actual survival outcomes. These prediction results also were confirmed in the independent internal and external validation cohorts. CONCLUSIONS: The 3 stratification classifications enabled satisfactory risk evaluation of early recurrence in HCC patients with MVI after hepatectomy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Estudos Retrospectivos , Neoplasias Hepáticas/cirurgia , Árvores de Decisões
5.
Langmuir ; 39(24): 8463-8474, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37289976

RESUMO

Surface chemistry plays a critical role in the ion structuring of ionic liquids (ILs) at the interfaces of electrodes and controls the overall energy storage performance of the system. Herein, we functionalized the gold (Au) colloid probe of an atomic force microscope with -COOH and -NH2 groups to explore the effect of different surface chemical properties on the ion structuring of an IL. Aided by colloid-probe atomic force microscopy (AFM), the ion structuring of an imidazolium IL, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6], abbreviated as BP hereafter), on the Au electrode surface and the ion response to the change in the surface chemistry are investigated. AFM morphologies, contact angles, and approaching force-distance curves of the BP IL on the functionalized Au surfaces exhibited that the IL forms a more obvious layering structure on the -COOH-terminated Au surface (Au-COOH), while it forms heterogeneous and aggregating droplets on the -NH2 surface (Au-NH2). The formed uniform and aggregation-free ion layers in the vicinity of the Au-COOH surface are due to the π-π+ stacking interaction between the delocalized π+ electrons from the imidazolium ring in the IL [BMIM]+ cation and the localized π electrons from the sp2 carbon on the -COOH group. The in situ observation of nano-friction and torsional resonance frequency at the IL-electrode interfaces further demonstrated the ion structuring of the IL at Au-COOH, which results in a more sensitive electrochemical response associated with a faster capacitive process.

6.
Langmuir ; 39(17): 5956-5969, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37084536

RESUMO

It is significant to understand the interfacial interactions involved between the cellulose acetate (CA) and dispersed nanomaterials, in which the enhanced interaction improves the mechanical behavior of CA. In this work, the amendments of CA with SiO2 nanoparticles have been found to be endowed by grafting varying concentrations (0, 3, 5, and 6%) of octadecyltrichlorosilane (OTS). Aided by SiO2 colloid probe atomic force microscopy (AFM with a probe diameter of 20 µm), the adhesion force between CA and SiO2 is found to be programmable by tuning OTS concentrations functionalized onto SiO2 surfaces. The adhesion forces of 5% OTS-functionalized SiO2 with CA are the strongest, followed by the ones of 0, 3, and 6% OTS, resulting in a smoother and denser morphology on the film with 5% OTS. The AFM-measured approaching force-distance curves have been further compared to predictions by the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, in which the XDLVO force is summed as the Liftshitz-van der Waals force (FLW), the electrostatic double-layer force (FEL), and the acid-base interaction force (FAB). FLW and FEL do not change significantly with OTS concentrations functionalized onto SiO2. However, FAB is sensitive to the functionalized OTS concentration onto SiO2 and significantly contributes to the interaction force of the composite films with 5% OTS, promoting the formation of a smooth and dense surface feature with a considerable mechanical performance demonstrated by load-displacement curves from a nanoindenter. This is highly encouraging and suggests that nanomaterials can be incorporated into CA to effectively improve their mechanical compatibility by programming the interaction between the CA matrix and nanomaterials.

7.
Langmuir ; 39(51): 18730-18745, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38095601

RESUMO

Through analysis of the statistical mechanical equations for a thin adsorbed film (gas, liquid, or solid) on a solid substrate or confined within a pore, it is possible to express the equilibrium thermodynamic properties of the film as a function of just two dimensionless parameters: a nanoscale wetting parameter, αw, and pore width, H*. The wetting parameter, αw, is defined in terms of molecular parameters for the adsorbed film and substrate and so is applicable at the nanoscale and for films of any phase. The main assumptions in the treatment are that (a) the substrate structure is not significantly affected by the adsorbed layer and (b) the diameter of the adsorbate molecules is not very small compared to the spacing of atoms in the solid substrate. We show that different surface geometries of the substrate (e.g., slit, cylindrical, and spherical pores) and various models of wall heterogeneity can be accounted for through a well-defined correction to the wetting parameter; no new dimensionless variables are introduced. Experimental measurements are reported for contact angles for various liquids on several planar substrates and are shown to be closely correlated with the nanoscale wetting parameter. We apply this approach to phase separation in nanopores of various geometries. Molecular simulation results for the phase diagram in confinement, obtained by the flat histogram Monte Carlo method, are reported and are shown to be closely similar to experimental results for capillary condensation, melting, and the triple point. The value of the wetting parameter, αw, is shown to determine the qualitative behavior (e.g., increase vs decrease in the melting temperature, capillary condensation vs evaporation), whereas the pore width determines the magnitude of the confinement effect. The triple point temperature and pressure for the confined phase are always lower than those for the bulk phase for all cases studied.

8.
Eur Radiol ; 33(7): 4554-4563, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36809432

RESUMO

OBJECTIVE: To investigate the findings of magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), and serum metabolomics for differentiating pre-eclampsia (PE) from gestational hypertension (GH). METHODS: This prospective study enrolled 176 subjects including a primary cohort with healthy non-pregnant women (HN, n = 35), healthy pregnant women (HP, n = 20), GH (n = 27), and PE (n = 39) and a validation cohort with HP (n = 22), GH (n = 22), and PE (n = 11). T1 signal intensity index (T1SI), apparent diffusion coefficient (ADC) value, and the metabolites on MRS were compared. The differentiating performances of single and combined MRI and MRS parameters for PE were evaluated. Serum liquid chromatography-mass spectrometry (LC-MS) metabolomics was investigated by sparse projection to latent structures discriminant analysis. RESULTS: Increased T1SI, lactate/creatine (Lac/Cr), and glutamine and glutamate (Glx)/Cr and decreased ADC value and myo-inositol (mI)/Cr in basal ganglia were found in PE patients. T1SI, ADC, Lac/Cr, Glx/Cr, and mI/Cr yielded an area under the curves (AUC) of 0.90, 0.80, 0.94, 0.96, and 0.94 in the primary cohort, and of 0.87, 0.81, 0.91, 0.84, and 0.83 in the validation cohort, respectively. A combination of Lac/Cr, Glx/Cr, and mI/Cr yielded the highest AUC of 0.98 in the primary cohort and 0.97 in the validation cohort. Serum metabolomics analysis showed 12 differential metabolites, which are involved in pyruvate metabolism, alanine metabolism, glycolysis, gluconeogenesis, and glutamate metabolism. CONCLUSIONS: MRS is expected to be a noninvasive and effective tool for monitoring GH patients to avoid the development of PE. KEY POINTS: • Increased T1SI and decreased ADC value in the basal ganglia were found in PE patients than in GH patients. • Increased Lac/Cr and Glx/Cr, and decreased mI/Cr in the basal ganglia were found in PE patients than in GH patients. • LC-MS metabolomics showed that the major differential metabolic pathways between PE and GH were pyruvate metabolism, alanine metabolism, glycolysis, gluconeogenesis, and glutamate metabolism.


Assuntos
Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Humanos , Feminino , Gravidez , Estudos Prospectivos , Espectroscopia de Ressonância Magnética , Ácido Glutâmico/metabolismo , Creatina/metabolismo , Metabolômica , Piruvatos , Alanina
9.
Hepatobiliary Pancreat Dis Int ; 22(6): 570-576, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36858891

RESUMO

BACKGROUND: More than 50% of patients with colorectal cancer develop liver metastases. Hepatectomy is the preferred treatment for resectable liver metastases. This review provides a perspective on the utility and relevant prognostic factors of repeat hepatectomy in recurrent colorectal liver metastasis (CRLM). DATA SOURCES: The keywords "recurrent colorectal liver metastases", "recurrent hepatic metastases from colorectal cancer", "liver metastases of colorectal cancer", "repeat hepatectomy", "repeat hepatic resection", "second hepatic resection", and "prognostic factors" were used to retrieve articles published in the PubMed database up to August 2020. Additional articles were identified by a manual search of references from key articles. RESULTS: Despite improvements in surgical methods and perioperative chemotherapy, recurrence remains common in 37%-68% of patients. Standards or guidelines for the treatment of recurrent liver metastases are lacking. Repeat hepatectomy appears to be the best option for patients with resectable metastases. The commonly reported prognostic factors after repeat hepatectomy were R0 resection, carcinoembryonic antigen level, the presence of extrahepatic disease, a short disease-free interval between initial and repeat hepatectomy, the number (> 1) and size (≥ 5 cm) of hepatic lesions, requiring blood transfusion, and no adjuvant chemotherapy after initial hepatectomy. The median overall survival after repeat hepatectomy ranged from 19.3 to 62 months, and the 5-year overall survival ranged from 21% to 73%. Chemotherapy can act as a test for the biological behavior of tumors with the goal of avoiding unnecessary surgery, and a multimodal approach involving aggressive chemotherapy and repeat hepatectomy might be the treatment of choice for patients with early recurrent CRLM. CONCLUSIONS: Repeat hepatectomy is a relatively safe and effective treatment for resectable recurrent CRLM. The presence or absence of prognostic factors might facilitate patient selection to improve short- and long-term outcomes.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Hepatectomia/efeitos adversos , Prognóstico , Neoplasias Colorretais/patologia , Reoperação , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos
10.
Plant J ; 108(1): 40-54, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34252236

RESUMO

Maize is an important crop worldwide, as well as a valuable model with vast genetic diversity. Accurate genome and annotation information for a wide range of inbred lines would provide valuable resources for crop improvement and pan-genome characterization. In this study, we generated a high-quality de novo genome assembly (contig N50 of 15.43 Mb) of the Chinese elite inbred line RP125 using Nanopore long-read sequencing and Hi-C scaffolding, which yield highly contiguous, chromosome-length scaffolds. Global comparison of the RP125 genome with those of B73, W22, and Mo17 revealed a large number of structural variations. To create new germplasm for maize research and crop improvement, we carried out an EMS mutagenesis screen on RP125. In total, we obtained 5818 independent M2 families, with 946 mutants showing heritable phenotypes. Taking advantage of the high-quality RP125 genome, we successfully cloned 10 mutants from the EMS library, including the novel kernel mutant qk1 (quekou: "missing a small part" in Chinese), which exhibited partial loss of endosperm and a starch accumulation defect. QK1 encodes a predicted metal tolerance protein, which is specifically required for Fe transport. Increased accumulation of Fe and reactive oxygen species as well as ferroptosis-like cell death were detected in qk1 endosperm. Our study provides the community with a high-quality genome sequence and a large collection of mutant germplasm.


Assuntos
Genoma de Planta/genética , Zea mays/genética , Produtos Agrícolas , Endosperma/genética , Endosperma/metabolismo , Endogamia , Mutação , Fenótipo , Melhoramento Vegetal , Banco de Sementes , Sementes/genética , Sementes/metabolismo , Amido/metabolismo , Zea mays/metabolismo
11.
Small ; 18(22): e2200532, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35318812

RESUMO

Accumulation of snow and ice often causes problems and even dangerous situations for both industry and the general population. Passive de-icing technologies, e.g., hydrophobic, liquid-infused bionic surfaces, have attracted more and more attention compared with active de-icing technologies, e.g., electric heating, hot air heating, due to the passive de-icing technology's lower energy consumption and sustainability footprint. Using passive de-icing coatings seems to be one of the most promising solutions. However, the previously reported de-icing coatings suffer from high ice adhesion strength or short service life caused by wear. An intrinsic self-healing material based on poly-silicone-urea is developed in this work to address these problems. The material is prepared by introducing dynamic disulfide bonds into the hard phase of the polymer. Experimental results indicate that this poly-silicone-urea has a self-healing efficiency of close to 99%. More interestingly, it is found that the coating prepared from this poly-silicone-urea has a super low ice adhesion force, only 7 ± 1 kPa, which is almost the lowest value compared with previous intrinsic self-healing de-/anti-icing reports. This material can maintain low ice adhesion strength after healing. This intrinsic self-healing poly-silicone-urea can meet several practical applications, opening the door for future sustainable anti-/de-icing technologies.


Assuntos
Gelo , Silicones , Humanos , Fenômenos Físicos , Propriedades de Superfície , Ureia
12.
J Transl Med ; 20(1): 92, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35168606

RESUMO

BACKGROUND: Chemoresistance gradually develops during treatment of epithelial ovarian cancer (EOC). Metabolic alterations, especially in vivo easily detectable metabolites in paclitaxel (PTX)-resistant EOC remain unclear. METHODS: Xenograft models of the PTX-sensitive and PTX-resistant EOCs were built. Using a combination of in vivo proton-magnetic resonance spectroscopy (1H-MRS), metabolomics and proteomics, we investigated the in vivo metabolites and dysregulated metabolic pathways in the PTX-resistant EOC. Furthermore, we analyzed the RNA expression to validate the key enzymes in the dysregulated metabolic pathway. RESULTS: On in vivo 1H-MRS, the ratio of (glycerophosphocholine + phosphocholine) to (creatine + phosphocreatine) ((GPC + PC) to (Cr + PCr))(i.e. Cho/Cr) in the PTX-resistant tumors (1.64 [0.69, 4.18]) was significantly higher than that in the PTX-sensitive tumors (0.33 [0.10, 1.13]) (P = 0.04). Forty-five ex vivo metabolites were identified to be significantly different between the PTX-sensitive and PTX-resistant tumors, with the majority involved of lipids and lipid-like molecules. Spearman's correlation coefficient analysis indicated in vivo and ex vivo metabolic characteristics were highly consistent, exhibiting the highest positive correlation between in vivo GPC + PC and ex vivo GPC (r = 0.885, P < 0.001). These metabolic data suggested that abnormal choline concentrations were the results from the dysregulated glycerophospholipid metabolism, especially choline metabolism. The proteomics data indicated that the expressions of key enzymes glycerophosphocholine phosphodiesterase 1 (GPCPD1) and glycerophosphodiester phosphodiesterase 1 (GDE1) were significantly lower in the PTX-resistant tumors compared to the PTX-sensitive tumors (both P < 0.01). Decreased expressions of GPCPD1 and GDE1 in choline metabolism led to an increased GPC levels in the PTX-resistant EOCs, which was observed as an elevated total choline (tCho) on in vivo 1H-MRS. CONCLUSIONS: These findings suggested that dysregulated choline metabolism was associated with PTX-resistance in EOCs and the elevated tCho on in vivo 1H-MRS could be as an indicator for the PTX-resistance in EOCs.


Assuntos
Neoplasias Ovarianas , Paclitaxel , Animais , Colina/metabolismo , Feminino , Humanos , Camundongos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Fosfolipases , Fosforilcolina/metabolismo , Espectroscopia de Prótons por Ressonância Magnética
13.
Langmuir ; 38(10): 3202-3211, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35253426

RESUMO

Separating proteins from their mixtures is an important process in a great variety of applications, but it faces difficult challenges as soon as the proteins are simultaneously of similar sizes and carry comparable net charges. To develop both efficient and sustainable strategies for the selective separation of similar proteins and to understand the underlying molecular mechanisms to enable the separation are crucial. In this work, we propose a novel strategy where the cholinium-based amino acid [Cho][Pro] ionic liquid (IL) is used as the trace additive and loaded physically on a mesoporous TiO2 surface for separating two similar proteins (lysozyme and cytochrome c). The observed selective adsorption behavior is explained by the hydration properties of the [Cho][Pro] loaded on the TiO2 surface and their partially dissociated ions under different pH conditions. As the pH is increased from 5.0 to 9.8, the degree of hydration of IL ions also increases, gradually weakening the interaction strength of the proteins with the substrates, more for lysozymes, leading to their effective separation. These findings were further used to guide the detection of the retention behavior of a binary mixture of proteins in high-performance liquid chromatography, where the introduction of ILs did effectively separate the two similar proteins. Our results should further stimulate the use of ILs in the separation of proteins with a high degree of mutual similarity.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Íons , Proteínas/química , Titânio
14.
Langmuir ; 38(48): 14550-14562, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36399765

RESUMO

Herein, a highly sensitive volatile organic compound (VOC) gas sensor is demonstrated using immobilized ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate, onto surfaces functionalized by the quaternary ammonium group -N+R, -COOH, and -NH2, i.e., N+-IL, COOH-IL, and NH2-IL, respectively. These functional groups ensure highly tunable interactions between the IL and surfaces, efficiently modulating the electrical resistance of the immobilized IL upon exposure to acetone and toluene. The immobilized IL to both acetone and toluene displays significant electronic resistance changes at a concentration of 150 ppm, falling in the order NH2-IL > N+-IL > COOH-IL for acetone while COOH-IL > NH2-IL > N+-IL for toluene. A better gaseous sensing ability is achieved in COOH-IL for toluene than acetone, while this does not hold in the case of NH2-IL and N+-IL surfaces because of the completely different ion structuring of the IL at these functionalized surfaces. The accelerated ion mobility in the IL that is immobilized onto functionalized surfaces is also responsible for the strong gaseous sensing response, which is demonstrated further by the atomic force microscopy-measured smaller friction coefficient. This is highly encouraging and suggests that ILs can be immobilized by a network formed by surface functionalization to easily and cheaply detect VOCs at ppm concentrations.


Assuntos
Líquidos Iônicos , Compostos Orgânicos Voláteis , Acetona , Tolueno , Gases
15.
Phys Chem Chem Phys ; 24(41): 25411-25419, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36250344

RESUMO

Atomic force microscopy (AFM) with a gold colloid probe modeled as the electrode surface is employed to directly capture the contact resonance frequency of two phosphonium-based ionic liquids (ILs) containing a common anion [BScB]- and differently lengthened cations ([P6,6,6,14]+ and [P4,4,4,8]+). The comparative interfacial studies are performed by creating IL films on the surface of gold, followed by measuring the wettability, thickness of the films, adhesion forces, surface morphology and AFM-probed contact resonance frequency. In addition, the cyclic voltammetry and impedance spectroscopy measurements of the neat ILs are measured on the surface of the gold electrode. The IL with longer cation alkyl chains exhibits a well-defined thin film on the electrode surface and enhanced the capacitance than the shorter chain IL. The AFM contact resonance frequency and force curves reveal that the longer IL prefers to form stiffer ion layers at the gold electrode surface, suggesting the "…anion-anion-cation-cation…" bilayer structure, in contrast, the shorter-chain IL forms the softer cation-anion alternating structure, i.e., "…anion-cation-anion-cation…".

16.
Phys Chem Chem Phys ; 24(21): 12808-12815, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35593233

RESUMO

Ionic liquids (ILs) interact strongly with many different types of solid surfaces in a wide range of applications, e.g. lubrication, energy storage and conversion, etc. However, due to the nearly immeasurable large number of potential ILs available, identifying the appropriate ILs for specific solid interfaces with desirable properties is a challenge. Theoretical studies are highly useful for effective development of design and applications of these complex molecular systems. However, obtaining reliable force field models and interaction parameters is highly demanding. In this work, we apply a new methodology by deriving the interaction parameters directly from the experimental data, determined by colloid probe atomic force microscopy (CP-AFM). The reliability of the derived interaction parameters is tested by performing molecular dynamics simulations to calculate translational self-diffusion coefficients and comparing them with those obtained from NMR diffusometry.

17.
Dermatol Ther ; 35(5): e15403, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35201628

RESUMO

Most plane warts are recalcitrant to treatment. Both cryotherapy and local hyperthermia have been applied to treat plane warts. However, no direct comparative study on their respective efficacy and safety has ever been performed. To assess the efficacy and safety of local hyperthermia at 43 ± 1°C versus liquid nitrogen cryotherapy for plane warts. Sequential patients with plane warts entered the study, either receiving cryotherapy or local hyperthermia therapy at the discretion of the patients and the recommendations of consultants. Cryotherapy with liquid nitrogen was delivered in two sessions 2 weeks apart, while local hyperthermia was delivered on three consecutive days, plus two similar treatments 10 ± 3 days later. The temperature over the treated skin surface was set at 43 ± 1°C for 30 min in each session. The primary outcome was the clearance rates of the lesions 6 months after treatment. Among the 194 participants enrolled, 183 were included in the analysis at 6 months. Local hyperthermia and cryotherapy achieved clearance rates of 35.56% (48/135) and 31.25% (15/48), respectively (p = 0.724); recurrence rates of 16.67% (8/48) and 53.33% (8/15) (p = 0.01); and adverse events rates of 20.74% (28/135) and 83.33% (40/48), respectively (p < 0.001). Cryotherapy had a higher pain score (p < 0.001) and a longer healing time (p < 0.001). Local hyperthermia at 43°C and cryotherapy had similar efficacy for plane warts. Local hyperthermia had a safer profile than cryotherapy but it required more treatment visits during a treatment course. More patients preferred local hyperthermia due to its treatment friendly nature.


Assuntos
Hipertermia Induzida , Verrugas , Crioterapia/efeitos adversos , Humanos , Hipertermia Induzida/efeitos adversos , Nitrogênio , Resultado do Tratamento , Verrugas/terapia
18.
Dig Dis Sci ; 67(7): 2792-2804, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34328590

RESUMO

BACKGROUND: Studies reported various diagnostic value of radiologic imaging modalities for diagnosis and management of colorectal cancer (CRC). AIMS: To summary the diagnosis and management of CRC using computed tomography colonography (CTC), magnetic resonance colonography (MRC), and positron emission tomography (PET)/computed tomography (CT). METHODS: Comprehensive literature searches were conducted in PubMed, EmBase, and the Cochrane library for studies published before April 2021. The diagnostic performance of CTC, MRC, and PET/CT for CRC was summarized. RESULTS: A total of 54 studies (17 studies for CTC, 8 studies for MRC, and 29 studies for PET/CT) were selected for final analysis. The sensitivity and specificity for CTC ranged from 27 to 100%, 88 to 100%, respectively, and the pooled sensitivity and specificity for CTC were 0.97 (95% CI 0.88-0.99) and 0.99 (95% CI 0.99-1.00). The sensitivity and specificity for MRC ranged from 48 to 100%, 60 to 100%, respectively, and the pooled sensitivity and specificity for MRC were 0.98 (95% C: 0.77-1.00) and 0.94 (95% CI 0.84-0.98). The sensitivity and specificity for PET/CT ranged from 84 to 100%, 33 to 100%, respectively, and the pooled sensitivity and specificity for PET/CT were 0.94 (95% CI 0.92-0.96) and 0.94 (95% CI 0.90-0.97). The area under the receiver operating characteristic curve for CTC, MRC, and PET/CT was 1.00 (95% CI 0.99-1.00), 0.99 (95% CI 0.98-1.00), and 0.97 (0.95% CI 0.95-0.98), respectively. CONCLUSIONS: This study suggested both CTC and MRC with relative higher diagnostic value for diagnosing CRC, while PET/CT with higher diagnostic value in detecting local recurrence for patients with CRC.


Assuntos
Colonografia Tomográfica Computadorizada , Neoplasias Colorretais , Colonografia Tomográfica Computadorizada/métodos , Neoplasias Colorretais/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Sensibilidade e Especificidade
19.
Nanotechnology ; 32(49)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34428749

RESUMO

In this work, intrinsic and p-type ZnO nanowires (NWs) have been synthesized. Pure intrinsic ZnO nanowires have been fabricated by direct oxidation method and their aspect ratio reached up to 271.3. Sb-doped ZnO nanowires were uniformly grown on Si substrates by chemical vapor deposition with diameters ranging from 0.5 to 5µm and lengths ranging from 100µm to 3 mm. Directional arrangement of nanowires has been realized by two self-assembly methods, pulling method and water flow method, and two kinds of ZnO nanodevices (strain sensor and homogenous p-n junction) were prepared and characterized based on the directional arranged nanowires. According to the current response of ZnO nanowire strain sensor, the deformation quantities of elastic plate under the action of external forces in orthogonalXandYdirection were calculated respectively. The ZnO nanowire homogenous p-n junction was made of two vertical Sb-doped and intrinsic ZnO nanowires. TheI-Vcharacteristic curve showed good rectification characteristics, and the forward turn-on voltage was about 10 V. However, since the current was too small due to the small carrier concentration in the ZnO single crystal, it is difficult to achieve electroluminescence at present.

20.
BMC Cardiovasc Disord ; 21(1): 215, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33906602

RESUMO

BACKGROUND: Myocardial ischemia-reperfusion injury (MIRI) is the main pathological manifestation of cardiovascular diseases such as myocardial infarction. The potential therapeutic effects of bone marrow-derived mesenchymal stem cells (BM-MSCs) and the participation of regulatory T cells (Tregs) in MIRI remains to be defined. METHODS: We used the experimental acute MIRI that was induced in mice by left ascending coronary ischemia, which were subsequently randomized to receive immunoglobulin G (IgG) or anti-CD25 antibody PC61 with or without intravenously injected BM-MSCs. The splenectomized mice underwent prior to experimental MIRI followed by intravenous administration of BM-MSCs. At 72 h post-MIRI, the hearts and spleens were harvested and subjected to cytometric and histologic analyses. RESULTS: CD25+Foxp3+ regulatory T cells were significantly elevated after MIRI in the hearts and spleens of mice receiving IgG + BM-MSCs and PC61 + BM-MSCs compared to the respective control mice (all p < 0.01). This was accompanied by upregulation of interleukin 10 and transforming growth factor ß1 and downregulation of creatinine kinase and lactate dehydrogenase in the serum. The post-MIRI mice receiving BM-MSCs showed attenuated inflammation and cellular apoptosis in the heart. Meanwhile, splenectomy compromised all therapeutic effects of BM-MSCs. CONCLUSION: Administration of BM-MSCs effectively alleviates MIRI in mice through inducing Treg activation, particularly in the spleen.


Assuntos
Transplante de Células-Tronco Mesenquimais , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/imunologia , Baço/imunologia , Linfócitos T Reguladores/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Apoptose , Creatina Quinase/sangue , Modelos Animais de Doenças , Imunoglobulina G/farmacologia , Interleucina-10/sangue , L-Lactato Desidrogenase/sangue , Masculino , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/imunologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Necrose , Fenótipo , Baço/efeitos dos fármacos , Baço/metabolismo , Esplenectomia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta1/sangue
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