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1.
Artigo em Inglês | MEDLINE | ID: mdl-38607206

RESUMO

Objective: This study aimed to assess the correlation and consistency between quantitative CT (QCT) and MRI asymmetric echo least squares estimation iterative water-lipid separation sequence (IDEAL-IQ) in determining pancreatic fat content in patients with type 2 diabetes. Methods: A total of 67 patients with type 2 diabetes mellitus who met the inclusion criteria were included in the study. QCT and MRIIDEAL-IQ technologies were utilized to evaluate the patients quantitatively. The pancreatic head, body, and tail regions were examined to measure the fat content and obtain the CT pancreatic fat fraction (CT-PFF) and MRI pancreatic fat fraction (MR-PFF). Pearson correlation analysis examined the relationship between diabetes-related factors and CT-PFF/MR-PFF. Additionally, Bland-Altman analysis assessed the consistency between CT-PFF and MR-PFF. Results: Among the 67 patients, 33 were males and 34 were females. The average age was (66.55±6.23) years, with an average abdominal circumference of (83.34 ± 10.10) cm. The mean values for glycated hemoglobin, fasting blood glucose, BMI, and liver fat content were (6.97±1.07) mmol • L-1, (6.83±1.82) mmol • L-1, (24.02 ± 2.96) kg/m², and (5.28±2.76)%, respectively. Pearson correlation analysis indicated a significant correlation between abdominal circumference, liver fat content, and MR-PFF (r=0.261, 0.267, P < .05). However, no significant correlation was observed between age, glycated hemoglobin, fasting blood glucose, BMI, and MR-PFF (all, P > .05). The minimum and maximum values for CT-PFF among the 67 patients were 7.3% and 60.3%, respectively, with an average value of (19.90±10.61)%. For MR-PFF, the minimum and maximum values were 2% and 48%, respectively, with an average value of (12.21±10.71)%. Pearson correlation analysis demonstrated a significant correlation between CT-PFF and MR-PFF (r = .842, P < .05). Bland-Altman analysis revealed an average bias value of 7.7% and a standard deviation of 5.6% for CT-PFF and MR-PFF. The mean 95% confidence interval ranged from 4.15% to 19.75% (P < .05), with 64 cases falling within this interval and 3 cases falling outside. Conclusion: A correlation exists between pancreatic fat content, abdominal circumference, and liver fat content. Both QCT and MRI can accurately quantify pancreatic fat content, and their correlation and consistency are relatively ideal. QCT technology is particularly suitable for patients with contraindications for magnetic resonance examination.

2.
Eur Radiol ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193925

RESUMO

OBJECTIVES: To prospectively investigate whether fully automated artificial intelligence (FAAI)-based coronary CT angiography (CCTA) image processing is non-inferior to semi-automated mode in efficiency, diagnostic ability, and risk stratification of coronary artery disease (CAD). MATERIALS AND METHODS: Adults with indications for CCTA were prospectively and consecutively enrolled at two hospitals and randomly assigned to either FAAI-based or semi-automated image processing using equipment workstations. Outcome measures were workflow efficiency, diagnostic accuracy for obstructive CAD (≥ 50% stenosis), and cardiovascular events at 2-year follow-up. The endpoints included major adverse cardiovascular events, hospitalization for unstable angina, and recurrence of cardiac symptoms. The non-inferiority margin was 3 percentage difference in diagnostic accuracy and C-index. RESULTS: In total, 1801 subjects (62.7 ± 11.1 years) were included, of whom 893 and 908 were assigned to the FAAI-based and semi-automated modes, respectively. Image processing times were 121.0 ± 18.6 and 433.5 ± 68.4 s, respectively (p <0.001). Scan-to-report release times were 6.4 ± 2.7 and 10.5 ± 3.8 h, respectively (p < 0.001). Of all subjects, 152 and 159 in the FAAI-based and semi-automated modes, respectively, subsequently underwent invasive coronary angiography. The diagnostic accuracies for obstructive CAD were 94.7% (89.9-97.7%) and 94.3% (89.5-97.4%), respectively (difference 0.4%). Of all subjects, 779 and 784 in the FAAI-based and semi-automated modes were followed for 589 ± 182 days, respectively, and the C-statistic for cardiovascular events were 0.75 (0.67 to 0.83) and 0.74 (0.66 to 0.82) (difference 1%). CONCLUSIONS: FAAI-based CCTA image processing significantly improves workflow efficiency than semi-automated mode, and is non-inferior in diagnosing obstructive CAD and risk stratification for cardiovascular events. CLINICAL RELEVANCE STATEMENT: Conventional coronary CT angiography image processing is semi-automated. This observation shows that fully automated artificial intelligence-based image processing greatly improves efficiency, and maintains high diagnostic accuracy and the effectiveness in stratifying patients for cardiovascular events. KEY POINTS: • Coronary CT angiography (CCTA) relies heavily on high-quality and fast image processing. • Full-automation CCTA image processing is clinically non-inferior to the semi-automated mode. • Full automation can facilitate the application of CCTA in early detection of coronary artery disease.

3.
J Exp Bot ; 74(17): 5104-5123, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37386914

RESUMO

Xyloglucan, a major hemicellulose, interacts with cellulose and pectin to assemble primary cell walls in plants. Loss of the xyloglucan galactosyltransferase MURUS3 (MUR3) leads to the deficiency of galactosylated xyloglucan and perturbs plant growth. However, it is unclear whether defects in xyloglucan galactosylation influence the synthesis of other wall polysaccharides, cell wall integrity, cytoskeleton behaviour, and endomembrane homeostasis. Here, we found that in mur3-7 etiolated seedlings cellulose was reduced, CELLULOSE SYNTHASE (CESA) genes were down-regulated, the density and mobility of cellulose synthase complexes (CSCs) were decreased, and cellulose microfibrils become discontinuous. Pectin, rhamnogalacturonan II (RGII), and boron contents were reduced in mur3-7 plants, and B-RGII cross-linking was abnormal. Wall porosity and thickness were significantly increased in mur3-7 seedlings. Endomembrane aggregation was also apparent in the mur3-7 mutant. Furthermore, mutant seedlings and their actin filaments were more sensitive to Latrunculin A (LatA) treatment. However, all defects in mur3-7 mutants were substantially restored by exogenous boric acid application. Our study reveals the importance of MUR3-mediated xyloglucan galactosylation for cell wall structural assembly and homeostasis, which is required for the stabilization of the actin cytoskeleton and the endomembrane system.


Assuntos
Arabidopsis , Arabidopsis/genética , Xilanos/química , Celulose , Parede Celular/química , Citoesqueleto de Actina , Pectinas , Plântula
4.
Clin Interv Aging ; 18: 667-675, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37101655

RESUMO

Background and Aims: Dyslipidemia is obviously an important risk factor for cardiovascular diseases, which might further lead to disability and death in aged population. We thus performed the current study to evaluate the association between chronological age and dyslipidemia. Subjects and Methods: A total number of 59,716 Chinese aged population (31,174 men and 28,542 women, average age 67.8y) were included in the current study. Age and sex were abstracted from medical records. Height, body weight, and blood pressure were measured by trained nurses. Serum concentration of total cholesterol (TC) and total triglycerides were performed by enzyme-linked immunosorbent method after at least 8-h fast. Dyslipidemia was defined if total cholesterol≥5.7 mmol/L, or total triglycerides≥1.7 mmol/L, or self-reported history of dyslipidemia. Results: The prevalence of dyslipidemia was 50.4% in the current study population. Compared to the youngest age group (60-64y), the adjusted odds ratio was 0.88 (95% CI: 0.84, 0.92), 0.77 (95% CI: 0.73, 0.81), 0.66 (95% CI: 0.61, 0.70), 0.55 (95% CI: 0.50, 0.59) for the participants who were 65 to 69, 70-74, 75-79, and ≥80 years old (p trend <0.001). Excluding participants with low body weight and with overweight and obesity, with high blood pressure and history of hypertension, with high fasting blood glucose and history of diabetes, generated similar results with main analysis. Conclusion: Chronological age was closely associated with the risk of dyslipidemia in Chinese aged population.


Assuntos
Dislipidemias , Hipertensão , Masculino , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , População do Leste Asiático , Fatores de Risco , Triglicerídeos , Dislipidemias/epidemiologia , Hipertensão/epidemiologia , Peso Corporal , Colesterol , HDL-Colesterol , Prevalência , China/epidemiologia
5.
Int J Biol Macromol ; 227: 354-364, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502946

RESUMO

In this study, the physicochemical properties of potato starch from different varieties were investigated. Furthermore, the relationships among gelatinization, retrogradation behavior, and impedance characteristics of potato starch gels were evaluated by texture analysis, low-field nuclear magnetic resonance spectroscopy, and electrical impedance spectroscopy. The results indicated amylose content was positively correlated with setback viscosity, and negatively correlated with To and ΔH. In addition, impedance values of potato starch gels differed in a frequency-dependent manner. Notably, higher frequencies resulted in low diffusion of ions in prepared gels, which combined with the concentration of mobile ions in free water, led to a gradual decrease in impedance module. Compared with phase values, impedance module showed high correlation with gelatinization parameters (To, Tp, and Tc) and viscosity parameters (peak temperature and setback viscosity), more notably at frequencies below 100 Hz. In this context, the electric current flowed through mobile ions that interacted with bound water attached to the starch molecules at lower voltage frequencies, and were repressed by the formation of an ordered and compact gel network during retrogradation. Collectively, these results indicate that impedance spectroscopy can be potentially used as an efficient and reliable method to predict gelatinization and retrogradation behavior of potato starch.


Assuntos
Solanum tuberosum , Solanum tuberosum/química , Impedância Elétrica , Amido/química , Amilose/química , Viscosidade , Géis/química
6.
Nat Commun ; 13(1): 7880, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36564406

RESUMO

Given the widespread significance of vicinal diamine units in organic synthesis, pharmaceuticals and functional materials, as well as in privileged molecular catalysts, an efficient and practical strategy that avoids the use of stoichiometric strong oxidants is highly desirable. We herein report the application of ligand-to-metal charge transfer (LMCT) excitation to 1,2-diazidation reactions from alkenes and TMSN3 via a coordination-LMCT-homolysis process with more abundant and greener iron salt as the catalyst. Such a LMCT-homolysis mode allows the generation of electrophilic azidyl radical intermediate from Fe-N3 complexes poised for subsequent radical addition into carbon-carbon double bond. The generated carbon radical intermediate is further captured by iron-mediated azidyl radical transfer, enabling dual carbon-nitrogen bond formation. This protocol provides a versatile platform to access structurally diverse diazides with high functional group compatibility from readily available alkenes without the need of chemical oxidants.


Assuntos
Alcenos , Ferro , Ferro/química , Alcenos/química , Ligantes , Oxidantes , Catálise , Carbono
7.
Chem Sci ; 13(32): 9361-9365, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36093005

RESUMO

In view of the widespread significance of amide functional groups in organic synthesis and pharmaceutical studies, an efficient and practical synthetic protocol that avoids the use of stoichiometric activating reagents or metallic reductants is highly desirable. A straight-forward pathway to access amides from abundant chemical feedstock would offer a strategic advantage in the synthesis of complex amides. We herein disclose a direct reductive amidation reaction using readily available aldehydes and nitroarenes enabled by photo-mediated hydrogen atom transfer catalysis. It avoids the use of metallic reductants and production of toxic chemical waste. While aldehydes represent a classic class of electrophilic synthons, the corresponding nucleophilic acyl radicals could be directly accessed by photo hydrogen atom transfer catalysis, enabling polarity inversion. Our method provides an orthogonal strategy to conventional amide couplings, tolerating nucleophilic substituents such as free alcohols and sensitive functional groups to amines such as carbonyl or formyl groups. The synthetic utilization of this reductive amidation is demonstrated by the late-stage modification of complex biologically active molecules and direct access of drug molecules leflunomide and lidocaine.

8.
Anal Bioanal Chem ; 414(7): 2481-2491, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35048137

RESUMO

A novel deep eutectic solvent-magnetic molecularly imprinted polymer (DES-MMIP) for the specific removal of oxalic acid (OA) was prepared by an environmentally friendly deep eutectic solvent, consisting of betaine, citric acid, and glycerol, which acted as the functional monomer for polymerization. The structure and morphology of DES-MMIPs were studied by X-ray diffraction, scanning and transmission electron microscopy, thermal gravimetric analysis, Fourier transform infrared spectroscopy, and vibrating sample magnetometer. DES-MMIPs had a core-shell structure, with magnetic iron oxide as the core, and showed good thermal stability and high adsorption capacity (18.73 mg/g) for OA. The adsorption process of OA by DES-MMIPs followed the pseudo-second-order kinetic model and Langmuir isotherm model. DES-MMIPs had significant selectivity for OA and their imprinting factor was 3.26. When applied to real samples, high performance liquid chromatography analysis showed that DES-MMIPs could remove OA from both spinach and blood serum. These findings provide potential methods for removal of OA from vegetables and for specific removal of OA in renal dialysis.


Assuntos
Impressão Molecular , Adsorção , Solventes Eutéticos Profundos , Humanos , Impressão Molecular/métodos , Ácido Oxálico , Solventes/química , Verduras
9.
Anal Chim Acta ; 1186: 339117, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34756250

RESUMO

Transferrin (Trf) is a new type of active drug targeting carrier and disease biomarker that regulates the balance of iron ions in human body. The recognition and isolation of Trf is of great significance for disease diagnosis and treatment. Thus, a new type of magnetic dual affinity epitope molecularly imprinted polymer coated on Fe3O4 nanoparticles (Fe3O4@DEMIP) was successfully prepared for specific recognition of Trf. C-terminal nonapeptide and Trf glycan were selected as bi-epitope templates for metal chelation and boron affinity immobilization, respectively. 4-vinylphenylboric acid (4-VP), N-isopropyl acrylamide (NIPAM) and zinc acrylic were used as functional monomers. Results showed that Fe3O4@DEMIP exhibited excellent specific recognition ability adsorption capacity toward Trf, with an adsorption of 43.96 mg g-1 (RSD = 3.28%) and a more satisfactory imprinting factor (about 6.60) than that of other reported imprinting methods. In addition, Fe3O4@DEMIP displayed pH, temperature and magnetic sensitivity properties to realize temperature and pH-controlled recognition and release of target proteins and magnetic rapid separation. Furthermore, the Fe3O4@DEMIP coupled with high-performance liquid chromatography (HPLC) analysis was successfully used for specific recognition of Trf in biosamples. This study provides a reliable protocol for preparing metal chelation and boron affinity dual affinity bi-epitope molecularly imprinted polymers for synergistic and efficient recognition of biomacromolecules in the complex biological systems.


Assuntos
Impressão Molecular , Polímeros , Adsorção , Epitopos , Humanos , Transferrina
10.
Food Chem ; 363: 130286, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34120040

RESUMO

The molecular basis of the pungency of sanshool dietary components from the Zanthoxylum species has been firstly addressed by constructing the statistically significant and highly predictive quantitative structure-pungency relationship models along with the pharmacophore models. The important pungent structural characters in the isobutylamide moiety and linear carbon chains were elucidated in this study that maintained the suitable spatial packing and electrostatic interactions with their receptors. Our results also revealed that the amide moiety, N-isobutyl moiety with suitable bulky and restricted electronegative substituents, and the relatively long straight carbon chains with suitable (conjugated) CC bonds or heteroatoms at regular intervals were essential for the high pungency. The pungency of 42 new sanshools was predicted, compared with the rough experimental data, and ultimately classified into weak, medium and strong types. Most of these sanshools were found to have good oral bioavailability and acceptable pharmacokinetic properties.


Assuntos
Zanthoxylum , Amidas , Dieta , Eletricidade Estática
11.
Food Chem ; 353: 129429, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33714121

RESUMO

The mechanistic insights into the oral pungency of capsaicin-related dietary components have been elucidated from the spatial structural perspectives by establishing statistically significant and highly predictive three-dimensional quantitative structure-property relationship models. Our results visualized the possible favorable and unfavorable steric and electrostatic interactions with the pungent receptors with the assistance of pharmacophore models, and revealed the suitable electronegative/positive or bulky substitutions in the vanillyl group, amide moiety, linear alkyl chain and their adjacent structural area of capsaicin required for the desired pungency, which was not only complementary to the viewpoints proposed in our previous structure-pungency correlations, but also was applied to clearly clarify the pungent differences in compounds, and well predict the pungency of 21 capsaicin analogs though with ambiguous experimental data on pungency. Hopefully, this work would benefit the overall understanding of the pungent mechanism and facile discovery/design of analogs with desired pungency to expand their applications in foods.


Assuntos
Capsaicina/química , Análise de Alimentos/métodos , Capsaicina/análise , Dieta , Humanos , Relação Quantitativa Estrutura-Atividade , Eletricidade Estática
12.
Front Cardiovasc Med ; 8: 778010, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35174219

RESUMO

Coronary artery disease (CAD) is a major contributor to morbidity and mortality worldwide. Myocardial ischemia may occur in patients with normal or non-obstructive CAD on invasive coronary angiography (ICA). The comprehensive evaluation of coronary CT angiography (CCTA) integrated with fractional flow reserve derived from CCTA (CT-FFR) to CAD may be essential to improve the outcomes of patients with non-obstructive CAD. China CT-FFR Study-2 (ChiCTR2000031410) is a large-scale prospective, observational study in 29 medical centers in China. The primary purpose is to uncover the relationship between the CCTA findings (including CT-FFR) and the outcome of patients with non-obstructive CAD. At least 10,000 patients with non-obstructive CAD but without previous revascularization will be enrolled. A 5-year follow-up will be performed. The primary endpoint is the occurrence of major adverse cardiovascular events (MACE), including all-cause mortality, non-fatal myocardial infarct, unplanned revascularization, and hospitalization for unstable angina. Clinical characteristics, laboratory and imaging examination results will be collected to analyze their prognostic value.

13.
RSC Adv ; 11(22): 13486-13496, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35423884

RESUMO

In this work, an efficient and sensitive magnetic molecularly imprinted polymer with zein and deep eutectic solvents (ZDM-MIPs) was designed and synthesized to exclusively adsorb and detect aspartame (ASP). We used zein, together with deep eutectic solvents (DESs) and Fe3O4 as the cross-linker, functional monomer and support material, respectively. A magnetic glassy carbon electrode (MGCE) modified with ZDM-MIPs was used for selective recognition of ASP. The electrochemical response of the ZDM-MIPs-MGCE for quantification of ASP was evaluated with a portable electrochemical detection station with differential pulse voltammetry and cyclic voltammetry. The responses of ZDM-MIPs-MGCE signified a good linear relationship with ASP concentrations in the range of 0.1-50 µg mL-1. The sensor systems showed good accuracy and precision, with recovery percentages between 84% and 107%. These results suggested that the obtained ZDM-MIPs exhibited good adsorption performance for ASP in soft drinks, and this method could be used to determine ASP content in actual food samples.

14.
Carbohydr Polym ; 152: 70-78, 2016 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-27516251

RESUMO

It has been reported in our previous work that selenized Artemisia sphaerocephala polysaccharides (SeASPs) with the Se content range of 168-1703µg/g were synthesized by using Na2SeO3/HNO3/BaCl2 system. In the present work, the solution property of SeASP was studied by using size exclusion chromatography combined with multi angle laser light scattering (SEC-MALLS). A decrease in df values indicated that SeASPs with different conformational features that were highly dependent on MW. SeASPs exhibited a more rigid conformation (df value of 1.29-1.52) in low molecular weight range (MW of 1.026-1.426×10(4)g/mol) and compact spherical conformation in high molecular weight range (MW of 2.268-4.363×10(4)g/mol). It could be due to the degradation of polysaccharide chains in HNO3, which was supported in monosaccharide composition analysis. Congo red (CR) spectrophotometric method and atomic force microscopy (AFM) results also confirmed the conformational transition and the evidence on the shape of the rigid chains. In vitro anti-tumor assays, SeASP2 displayed greater anti-proliferative effects against three tumor cell lines (hepatocellular carcinoma HepG-2 cells, lung adenocarcinom A549 cells and cervical squamous carcinoma Hela cells) in a dose-dependent manner. This suggested that selenylation could significantly enhance the anti-tumor activities of polysaccharide derivatives in vitro.


Assuntos
Antineoplásicos Fitogênicos , Artemisia/química , Neoplasias/tratamento farmacológico , Polissacarídeos , Selênio/química , Células A549 , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Relação Dose-Resposta a Droga , Células HeLa , Células Hep G2 , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Polissacarídeos/síntese química , Polissacarídeos/química , Polissacarídeos/farmacologia
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