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1.
Electrophoresis ; 39(20): 2558-2565, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29998461

RESUMEN

Thiol-ene click reaction of N-acetyl-L-cysteine methyl ester to codeine, followed by reaction with allyl isocyanate and hydrolysis to the corresponding zwitterionic chiral selector and its subsequent bonding to the surface of a methacrylate monolith provided a new chiral capillary column for enantiomer separation of chiral acids and chiral bases. First, the epoxy groups of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith were converted into amine residues, followed by reaction with allylglycidyl ether. In this way, a spacer arm was bonded to the surface before coating and cross-linking poly(3-mercaptopropyl methylsiloxane) (PMPMS) via radical addition (thiol-ene click reaction) to the surface. In order to improve the performance of the monolithic chiral stationary phase, thio ether and residual thiol groups were oxidized to sulfonyl and sulphonate groups, respectively. This novel chiral stationary phase (CSP) was evaluated by capillary electrochromatography (CEC) using two chiral model compounds, namely N-3,5-dinitrobenzoyl-R,S-leucine (retained by anion-exchange mechanism) and mefloquine (by cation-exchange process). The ion-exchange retention mechanism on the CSP was characterized for these two counterionic model solutes by varying the mobile phase composition, including the nature of solvents, the concentration of counter-ions and co-ions, and the acid-to-base ratio. A series of chiral ß-blockers and amino acid derivatives was used to further check the performance of the modified monolith under the optimal conditions. Several enantiomers were baseline resolved with reasonable peak efficiencies (up to 60,000 theoretical plates per meter for the second eluted enantiomer).


Asunto(s)
Electrocromatografía Capilar/métodos , Codeína/química , Metacrilatos/química , Concentración de Iones de Hidrógeno , Leucina/análogos & derivados , Leucina/química , Leucina/aislamiento & purificación , Mefloquina/química , Mefloquina/aislamiento & purificación , Modelos Químicos , Siloxanos/química , Estereoisomerismo
2.
J Oral Microbiol ; 16(1): 2391640, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161727

RESUMEN

Gastric cancer is one of the most common malignant tumors worldwide and has a high mortality rate. However, tests for the early screening and diagnosis of gastric cancer are limited and invasive. Certain oral microorganisms are over-expressed in gastric cancer, but there is heterogeneity among different studies. Notably, each oral ecological niche harbors specific microorganisms. Among them, tongue coating, saliva, and dental plaque are important and unique ecological niches in the oral cavity. The colonization environment in different oral niches may be a source of heterogeneity. In this paper, we systematically discuss the latest developments in the field of the oral microbiota and gastric cancer and elucidate the enrichment of microorganisms in the oral ecological niches of the tongue coatings, saliva, and dental plaque in gastric cancer patients. The various potential mechanisms by which the oral microbiota induces gastric cancer (activation of an excessive inflammatory response; promotion of proliferation, migration, invasion, and metastasis; and secretion of carcinogens, leading to imbalance in gastric microbial communities) are explored. In this paper, we also highlight the applications of the rapeutics targeting the oral microbiota in gastric cancer and suggests future research directions related to the relationship between the oral microbiota and gastric cancer.

3.
Talanta ; 261: 124665, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37209585

RESUMEN

The biological molecules used in the sandwich detection method have problems such as complex extraction processes, high costs, and uneven quality. Therefore we integrated glycoprotein molecularly controllable-oriented surface imprinted magnetic nanoparticles (GMC-OSIMN) and boric acid functionalized pyrite nanozyme probe (BPNP) to replace the traditional antibody and horseradish peroxidase for sensitive detection of glycoproteins through sandwich detection. In this work, a novel nanozyme functionalized with boric acid was used to label glycoproteins that were captured by GMC-OSIMN. The substrate in the working solution catalyzed by the nanozyme labeled on the protein underwent visible color changes to the naked eye, and the generated signal can be quantitatively detected by a spectrophotometer, and the best color development conditions of the novel nanozyme under the influence of many factors were determined through multi-dimensional investigation. The optimum conditions of sandwich are optimized with ovalbumin (OVA), and it was extended to the detection of transferrin (TRF) and alkaline phosphatase (ALP) in the application. The detection range for TRF was 2.0 × 10-1-1.0 × 104 ng mL-1 with a detection limit of 1.32 × 10-1 ng mL-1, The detection range for ALP was 2.0 × 10-3-1.0 × 102 U L-1 with the detection limit of 1.76 × 10-3 U L-1. This method was subsequently used to detect TRF and ALP levels in 16 liver cancer patients, and the standard deviation of the test results of each patient was less than 5.7%.


Asunto(s)
Colorimetría , Polímeros , Humanos , Polímeros/química , Colorimetría/métodos , Glicoproteínas/química , Transferrina/análisis , Fosfatasa Alcalina/metabolismo
4.
Environ Sci Pollut Res Int ; 27(28): 35618-35625, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32613503

RESUMEN

We aimed to quantify the relationship between the outpatient visits of hand, foot, and mouth disease (HFMD) and diurnal temperature range (DTR). The data of daily HFMD outpatient visits and meteorological parameters were obtained. A distributed lag nonlinear model combined with generalized linear model was used to estimate simultaneously nonlinear and delayed effects between DTR and daily HFMD outpatient visits after controlling confounding factors. A total of 15,275 HFMD visits were enrolled. DTR was significantly associated with HFMD outpatient visits in children. High DTR (P75: 11.4 °C) and extreme DTR (P95: 15.3 °C) were compared with 8.5 °C, and HFMD visits increased by a maximum of 3.93% (95% CI: 1.82 to 6.07%) and 4.47% (95% CI: 0.45 to 8.65%) in single-day lag effect, respectively. Furthermore, the extreme DTR effect decreased with the lag time and lasted for 10 days. Cumulative lag effects with markedly increasing percent of visits are over 64.88%. Furthermore, the effects were most pronounced among female children and children aged 0-2 years. Our study suggested that DTR changes were associated with HFMD outpatient visits, and populations of female and aged 0-2 years were more sensitive.


Asunto(s)
Enfermedad de Boca, Mano y Pie , Niño , Preescolar , China , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Pacientes Ambulatorios , Temperatura
5.
Bioresour Technol ; 261: 70-75, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29653336

RESUMEN

The aim of this work was to study the degradation of lignin in raw wood via pretreatment with heteropoly acids as substitutes for traditional H2SO4 in γ-valerolactone/water. By optimizing catalyst concentration, reaction time and temperature, the optimal lignin degradation conditions are obtained (130 °C, 3 h and 20 mM silicotungstic acid). SEM and FTIR measurements demonstrated the efficient lignin degradation ability of HPAs in the GVL/H2O solvent, with negligible damage to cellulose within the raw wood. Furthermore, an elaborated enzymatic hydrolysis study of the thus obtained cellulosic feedstock revealed its suitability for enzymatic digestion, with great potential as starting material for the production of fermentable sugar from biomass in future biorefinery applications.


Asunto(s)
Lignina/metabolismo , Madera , Biomasa , Celulosa , Hidrólisis , Lactonas , Eliminación de Residuos , Agua
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