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1.
Small ; : e2402472, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38813745

RESUMEN

Despite significant advancements, current self-healing materials often suffer from a compromise between mechanical robustness and functional performance, particularly in terms of conductivity and responsiveness to environmental stimuli. Addressing this issue, the research introduces a self-healable and conductive copolymer, poly(ionic liquid-co-acrylic acid) (PIL-co-PAA), synthesized through free radical polymerization, and further optimized by incorporating thermoplastic polyurethane (TPU). This combination leverages the unique properties of each component, especially ion-dipole interactions and hydrogen bonds, resulting in a material that exhibits exceptional self-healing abilities and demonstrates enhanced mechanical properties and electrical conductivity. Moreover, the PIL-co-PAA/TPU films showcase alkaline-responsive behavior, a feature that broadens their applicability in dynamic environments. Through systematic characterization, including thermogravimetric analysis, tensile testing, and electrical properties measurements, the mechanisms behind the improved performance and functionality of these films are elucidated. The conductivities and ultimate tensile strength (σuts) of the PIL-co-PAA/TPU films regain 80% under 8 h healing process. To extend the applications for wearable devices, the self-healing properties of commercial cotton fabrics coated with the self-healable PIL-co-PAA are also investigated, demonstrating both self-healing and electrical properties. This study advances the understanding of self-healable conductive polymers and opens new avenues for their application in wearable technology.

2.
Mol Pharm ; 21(2): 854-863, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38235659

RESUMEN

Organic anion-transporting polypeptides (OATPs) 1B1 and 1B3 are two highly homologous transport proteins. However, OATP1B1- and 1B3-mediated estradiol-17ß-glucuronide (E17ßG) uptake can be differentially affected by clotrimazole. In this study, by functional characterization on chimeric transporters and single mutants, we find that G45 in transmembrane domain 1 (TM1) and V386 in TM8 are critical for the activation of OATP1B3-mediated E17ßG uptake by clotrimazole. However, the effect of clotrimazole on the function of OATP1B3 is substrate-dependent as clotrimazole does not stimulate OATP1B3-mediated uptake of 4',5'-dibromofluorescein (DBF) and rosuvastatin. In addition, clotrimazole is not transported by OATP1B3, but it can efficiently permeate the plasma membrane due to its lipophilic properties. Homology modeling and molecular docking indicate that E17ßG binds in a substrate binding pocket of OATP1B3 through hydrogen bonding and hydrophobic interactions, among which its sterol scaffold forms hydrophobic contacts with V386. In addition, a flexible glycine residue at position 45 is essential for the activation of OATP1B3. Finally, clotrimazole is predicted to bind at an allosteric site, which mainly consists of hydrophobic residues located at the cytoplasmic halves of TMs 4, 5, 10, and 11.


Asunto(s)
Estradiol/análogos & derivados , Transportadores de Anión Orgánico Sodio-Independiente , Transportadores de Anión Orgánico , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Clotrimazol/farmacología , Miembro 1B3 de la Familia de los Transportadores de Solutos de Aniones Orgánicos/metabolismo , Transportador 1 de Anión Orgánico Específico del Hígado/metabolismo , Simulación del Acoplamiento Molecular , Transportadores de Anión Orgánico/metabolismo , Transporte Biológico
3.
Neoplasma ; 69(6): 1373-1385, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36353938

RESUMEN

Aberrant DNA methylation of genes is closely linked to many aspects of tumor development. This study focuses on the effect of DNA hypermethylation of von Willebrand factor C domain containing 2 (VWC2) on colorectal cancer (CRC) progression and the underpinning mechanism. According to data in the bioinformatic systems, VWC2 had the highest degree of DNA methylation in colonic adenocarcinoma, and it showed DNA hypermethylation in rectal adenocarcinoma as well. CRC and the para-tumorous tissues were collected from 86 patients. VWC2 was expressed at low levels in CRC samples and inversely correlated with tumor stage and tumor biomarker expression. DNA hypermethylation and reduced expression of VWC2 were also detected in CRC cell lines HCT-116 and HT29. VWC2 overexpression suppressed the malignant growth of cells in vitro and in vivo. Co-immunoprecipitation and western blot assays showed that small ubiquitin-like modifier 1 (SUMO1) mediated SUMOylation of DNA methyltransferase 1 (DNMT1) and strengthened its protein stability, which promoted DNA methylation and suppression of the VWC2 gene. In summary, this study demonstrates that SUMO1-mediated activation of DNMT1 induces DNA methylation and downregulation of VWC2 in CRC to augment cancer development.


Asunto(s)
Adenocarcinoma , Neoplasias Colorrectales , Humanos , Metilación de ADN , Neoplasias Colorrectales/patología , ADN , Metiltransferasas/genética , Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo
4.
Molecules ; 27(18)2022 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-36144828

RESUMEN

Salvianic acid A (SAA), as the main bioactive component of the traditional Chinese herb Salvia miltiorrhiza, has important application value in the treatment of cardiovascular diseases. In this study, a two-step bioprocess for the preparation of SAA from l-DOPA was developed. In the first step, l-DOPA was transformed to 3,4-dihydroxyphenylalanine (DHPPA) using engineered Escherichia coli cells expressing membrane-bound L-amino acid deaminase from Proteus vulgaris. After that, the unpurified DHPPA was directly converted into SAA by permeabilized recombinant E. coli cells co-expressing d-lactate dehydrogenase from Pediococcus acidilactici and formate dehydrogenase from Mycobacterium vaccae N10. Under optimized conditions, 48.3 mM of SAA could be prepared from 50 mM of l-DOPA, with a yield of 96.6%. Therefore, the bioprocess developed here was not only environmentally friendly, but also exhibited excellent production efficiency and, thus, is promising for industrial SAA production.


Asunto(s)
Escherichia coli , Levodopa , Biocatálisis , Escherichia coli/genética , Formiato Deshidrogenasas , Ácidos Fenilpirúvicos
5.
Front Public Health ; 10: 855348, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35400049

RESUMEN

Background: A large body of emerging evidence suggests that per- and polyfluoroalkyl substances (PFAS) affect birth outcomes in various pathways, but the evidence is inconsistent. Therefore, this study aimed to systematically review the epidemiological evidence on PFAS exposure and birth outcomes. Methods: Three electronic databases were searched for epidemiological studies through February 13, 2021. We used random-effects meta-analysis for eight birth outcome indicators to calculate summary effect estimates for various exposure types. The risk of bias and the overall quality and level of evidence for each exposure-outcome pair were assessed. Results: The initial search identified 58 potentially eligible studies, of which 46 were ultimately included. Many PFAS were found to have previously unrecognized statistically significant associations with birth outcomes. Specifically, birth weight (BW) was associated with PFAS, with effect sizes ranging from -181.209 g (95% confidence interval (CI) = -360.620 to -1.798) per 1 ng/ml increase in perfluoroheptanesulfonate (PFHpS) to -24.252 g (95% CI = -38.574 to -9.930) per 1 ln (ng/ml) increase in perfluorodecaoic acid (PFDA). Similar patterns were observed between other PFAS and birth outcomes: perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) with birth length (BL) and ponderal index (PI), PFOS and perfluorododecanoic acid (PFDoDA) with head circumference (HC), PFHpS with gestational age (GA), and perfluorononanoic acid (PFNA) and PFHpS with preterm birth (PTB). Additionally, PFDA showed a statistically significant association with small for gestational age (SGA). The level of the combined evidence for each exposure-outcome pair was considered to be "moderate". Conclusion: This study showed that PFAS exposure was significantly associated with increased risks of various adverse birth outcomes and that different birth outcome indicators had different degrees of sensitivity to PFAS. Further studies are needed to confirm our results by expanding the sample size, clarifying the effects of different types or doses of PFAS and the time of blood collection on birth outcomes, and fully considering the possible confounders.


Asunto(s)
Contaminantes Ambientales , Fluorocarburos , Nacimiento Prematuro , Contaminantes Ambientales/efectos adversos , Fluorocarburos/efectos adversos , Edad Gestacional , Humanos , Recién Nacido
6.
Environ Sci Pollut Res Int ; 29(37): 55707-55727, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35320480

RESUMEN

Traffic noise has attracted much attention as a significant and intractable public health threat. This study was designed as a systematical review to explore the association of traffic noise with different indicators of obesity, thus providing updated quantitative estimates for the pooled effect estimates of the existing literature. We conducted an extensive search for epidemiological studies that investigated the association of traffic noise with obesity in three electronic databases till February 23, 2021. We used random-effects meta-analysis to calculate the summary effect estimates for each 10-dB(A) increase in noise and compared the highest with the lowest category of noise in relation to seven obesity indicators. Meanwhile, we assessed the risk of bias and the overall quality of the evidence of each study as well as the level of evidence for each exposure-outcome pair. The initial search identified 30 studies, 13 of which were ultimately included. The meta-analysis for the highest versus the lowest category of noise exposure was generally associated with higher waist circumfluence (WC) ranging from 0.326 cm (95% confidence interval (CI) = 0.078, 0.574) to 0.705 cm (95% CI = 0.071, 1.340) and higher odds of central obesity ranging from 1.055 (95% CI = 1.000, 1.109) to 1.167 (95% CI = 1.037, 1.298). When the continuous exposure (each 10 dB(A) increase in noise) was introduced, similar results were found. This study indicated positive associations of traffic noise with WC and central obesity. However, in consideration of some limitations, there is an urgent need for future studies to increase the sample size, discriminate the etiological differences in different noise and obesity indicators, and thoroughly consider socioeconomic status.


Asunto(s)
Adiposidad , Ruido del Transporte , Exposición a Riesgos Ambientales , Estudios Epidemiológicos , Humanos , Ruido del Transporte/efectos adversos , Obesidad/epidemiología , Obesidad/etiología , Obesidad Abdominal/etiología
7.
Langmuir ; 38(2): 801-809, 2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-34951309

RESUMEN

Surface-enhanced Raman scattering (SERS) has been a useful sensing technique, in which inelastic light scattering can be significantly enhanced by absorbing molecules onto rough metal surfaces or nanoparticles. Although many methods have been developed to prepare SERS substrates, it is still highly desirable and challenging to design SERS substrates, especially with highly ordered and controlled three-dimensional (3D) structures. In this work, we develop novel SERS substrates with regular volcano-shaped polymer structures using the versatile solvent on-film annealing method. Polystyrene (PS) nanospheres are first synthesized by surfactant-free emulsion polymerization and assembled on poly(methyl methacrylate) (PMMA) films. After annealing in acetic acid vapors, PMMA chains are selectively swollen and wet the surfaces of the PS nanospheres. By selectively removing the PS nanospheres using cyclohexane, volcano-shaped PMMA films can be obtained. Compared with flat PMMA films with water contact angles of ∼74°, volcano-shaped PMMA films exhibit higher water contact angles of ∼110° due to the sharp features and rough surfaces. The volcano-shaped PMMA films are then coated with gold nanoparticles (AuNPs) as SERS substrates. Using rhodamine 6G as the probe molecules, the SERS results show that the Raman signals of the volcano-shaped PMMA/AuNP hybrid substrates are much higher than those of the pristine PMMA films and PMMA films with AuNPs. For the volcano-shaped PMMA/AuNP hybrid substrates using 400 nm PS nanospheres, a high enhancement factor (EF) value of ∼1.12 × 105 with a detection limit of 10-8 M is obtained in a short integration time of 1 s. A linear calibration line with an R2 value of 0.918 is also established, demonstrating the ability to determine the concentrations of the analytes. This work offers significant insight into developing novel SERS substrates, which is crucial for improving the detection limits of analytes.

8.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3871-3876, 2020 Aug.
Artículo en Chino | MEDLINE | ID: mdl-32893583

RESUMEN

To establish high performance liquid chromatography(HPLC) fingerprints for crude and processed Ligustri Lucidi Fructus,and to evaluate their quality through the similarity calculation and chemical pattern recognition. The separation was performed with Syncronis C_(18) column(4.6 mm × 250 mm, 5 µm), with acetonitrile(A) and 0.1% phosphoric acid solution(B) as the mobile phase for gradient elution, and a detection wavelength of 280 nm. HPLC was used to detect 22 batches of crude and processed Ligustri Lucidi Fructus,and the Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(2012 Edition) was used to evaluate the similarity among 22 batches. The research on pattern recognition was conducted with cluster analysis(CA), principal component analysis(PCA), and partial least squares discriminate analysis(PLS-DA). HPLC fingerprints of crude and processed Ligustri Lucidi Fructus were established, with similarity ranging from 0.9 to 1.0. The crude and processed Ligustri Lucidi Fructus can be obviously distinguished by using CA, PCA and PLS-DA. According to the results of PLS-DA,11 constituents including hydroxytyrosol, tyrosol, specnuezhenide and oleuropein were the main marker components leading to the difference. The established fingerprint method is stable and reliable, and can provide method basis for quality control of crude and processed Ligustri Lucidi Fructus. Chemical pattern recognition is proved to be helpful in comprehensive quality control and evaluation of Ligustri Lucidi Fructus before and after the process.


Asunto(s)
Medicamentos Herbarios Chinos , Ligustrum , Cromatografía Líquida de Alta Presión , Frutas , Medicina Tradicional China
9.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3221-3228, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30325146

RESUMEN

Studies on effects of nitrogen deposition were mainly focused on temperate grasslands in Inner Mongolia of China. In addition, there are substantial differences between the present simulation methods and the natural nitrogen deposition. A three-year experiment was carried out to compare the effects of simulation methods (common urea and slow-released urea) and nitrogen deposition rates (0, 25, 50, 75, 100, 150, 200 and 300 kg N·hm-2·a-1) on soil nutrients and biological characteristics in Hulun Buir Grassland. We found that simulated nitrogen deposition had significant influences on soil chemical properties, biological properties and enzyme activities. With the increases of nitrogen deposition, soil pH declined with the greatest extent of 0.2 units, while the highest concentrations of total dissolved nitrogen (TDN) and dissolved organic carbon (DOC) increased by 5-7 times and 12%-36%, respectively. There was a decline trend for soil total phosphorus (TP) and organic phosphorus (TOP). Microbial biomass and metabolic activity increased firstly and then decreased. Moderate simulated nitrogen deposition rates significantly increased soil carbon, nitrogen and phosphorus related enzyme activities. Compared to common urea, using slow-released urea to simulate nitrogen deposition decelerate the decline of soil pH and the increase of dissolved nutrients, and smoothed the change of microbial biomass, metabolic activity, and nitrogen hydrolyzed enzyme activities. Overall, the results confirmed that continuous nitrogen input caused the decline of soil pH and the increase of bioavailable carbon and nitrogen, and then changed microbial biomass and activity.


Asunto(s)
Suelo , Biomasa , Carbono , China , Alimentos , Pradera , Nitrógeno , Fósforo , Microbiología del Suelo , Urea
10.
Ying Yong Sheng Tai Xue Bao ; 29(8): 2470-2476, 2018 Aug.
Artículo en Chino | MEDLINE | ID: mdl-30182584

RESUMEN

Soil organic C, N, P contents and their catalyzed enzyme activities play an important role in maintaining and supplying energy and nutrient in grasslands. There is no consensus on the effects of N deposition on soil organic nutrients and enzyme activities in grassland ecosystems. It remains unclear whether C addition will retard the negative effects of N deposition. We carried out an experiment in Hulun Buir grassland of Inner Mongolia to examine the effects of C and N additions on soil organic C, N, P and relative enzyme activities after three years treatments. The experiment was conducted with N treatments at five levels (0, 25, 50, 100 and 200 kg·hm-2·a-1) and with C treatments at three levels (0, 250 and 500 kg·hm-2·a-1). The results showed that higher levels of N addition significantly decreased dehydrogenase (DHA) and ß-1,4-N-acetylglucosaminidase (NAG) activities by 22.3% and 12.5%, respectively. Nitrogen addition had no significant effect on soil organic N and decreased the organic C and P contents by 6.6% and 14.5%, respectively. High C addition significantly increased DHA, ß-glucosidase (BG) activities and increased soil organic N and organic P by 15.1%, 12.2%, 1.9%, 2.6%, respectively. The results suggested that continuous N inputs inhibited microbial activities and caused losses of soil organic C and organic P. Carbon addition could enhance microbial activities and promote the secretion of enzymes and increase soil organic N and P. The combined C and N addition could play an important role in maintaining the balance and supply of soil C, N, and P in grassland ecosystem.


Asunto(s)
Carbono/metabolismo , Pradera , Nitrógeno/metabolismo , Fósforo/metabolismo , China , Ecosistema , Enzimas , Suelo , Microbiología del Suelo
11.
ISRN Rheumatol ; 2012: 215692, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22548187

RESUMEN

Objective. To analyse the potential risk factors of nosocomial infections in patients with active rheumatoid arthritis (RA). Methods. A total of 2452 active RA patients at Hospitals in Shanghai between January 2009 and February 2011 were analyzed. Their demographic and clinical characteristics were compared with those without infection, and the potential risk factors were determined by logistic regression analysis. Results. Multivariate analysis indicated the gender (OR = 0.70, 95% CI 0.53-0.92), duration in hospital (OR = 1.03 , 95%CI 1.01-1.05), number of organs involved (OR = 0.82, 95%CI 0.72-0.92), number of disease-modifying antirheumatic drugs ((DMARDs) (OR = 1.22, 95%CI 1.061-1.40)), corticosteroid therapy (OR = 1.02, 95%CI 1.01-1.03), peripheral white blood cell counts ((WBC) (OR = 1.04, 95%CI 1.00-1.08)), levels of serum albumin (OR = 0.98, 95%CI 0.97-0.99), and C-reactive protein ((CRP) (OR = 1.03 , 95%CI 1.01-1.04)) that were significantly associated with the risk of infections. Conclusion. The female patients, longer hospital stay, more organs involved, more DMARDs, corticosteroid usage, high counts of WBC, lower serum albumin, and higher serum CRP were independent risk factors of infections in active RA patients.

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