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1.
Carbohydr Res ; 538: 109094, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38564900

RESUMO

Human diseases often correlate with changes in protein glycosylation, which can be observed in serum or plasma samples. N-glycosylation, the most common form, can provide potential biomarkers for disease prognosis and diagnosis. However, glycoproteins constitute a relatively small proportion of the total proteins in human serum and plasma compared to the non-glycosylated protein albumin, which constitutes the majority. The detection of microheterogeneity and low glycan abundance presents a challenge. Mass spectrometry facilitates glycoproteomics research, yet it faces challenges due to interference from abundant plasma proteins. Therefore, methods have emerged to enrich N-glycans and N-linked glycopeptides using glycan affinity, chemical properties, stationary phase chemical coupling, bioorthogonal techniques, and other alternatives. This review focuses on N-glycans and N-glycopeptides enrichment in human serum or plasma, emphasizing methods and applications. Although not exhaustive, it aims to elucidate principles and showcase the utility and limitations of glycoproteome characterization.


Assuntos
Glicopeptídeos , Glicoproteínas , Humanos , Glicopeptídeos/química , Glicoproteínas/química , Glicosilação , Espectrometria de Massas/métodos , Polissacarídeos
2.
Planta Med ; 89(9): 903-915, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36706785

RESUMO

Gnaphalium affine is traditionally used to treat hyperuricemia and gout in China. Recently, the hypouricemic and renal protective effects of G. affine extract (GAD) have been deeply evaluated. However, little is known about the pharmacokinetics (PKs) of bioactive constituents in GAD. This study is aimed at investigating the individual and holistic pharmacokinetics of 10 bioactive components (including caffeic acid, caffeoylquinic acids, and flavonoids) in rats after single and multiple administrations of GAD. GAD is orally dosed to normal male rats at doses of 225, 450, or 900 mg/kg/day for 10 consecutive days and also orally administrated to uric acid nephropathy (UAN) rats at a dose of 900 mg/kg/day for 28 consecutive days. Integrated PKs of multiple components are calculated by area under the curve (AUC)-based weighting approach. All the components show a double-peak phenomenon in terms of their plasma concentration-time curves, suggesting that the components undergo enterohepatic circulation. The integrated AUC increases in a good dose-proportional manner with GAD dose. Compared with that in normal rats, the plasma exposure of caffeic acid and caffeoylquinic acids increases by 2.3- to 4.3-fold after 10-day chronic treatment of 900 mg/kg GAD in UAN rats. Modest drug accumulation is observed after 28-day chronic treatment.


Assuntos
Gnaphalium , Hiperuricemia , Ratos , Animais , Rim/metabolismo , Hiperuricemia/tratamento farmacológico , Área Sob a Curva , Administração Oral , Extratos Vegetais/farmacologia
3.
Phytomedicine ; 102: 154203, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35660349

RESUMO

BACKGROUND: Gnaphalium affine D. Don extract (GAD) enhanced efficacy and reduced toxicity of benzbromarone (BBR) in combination use. However, little is known about effects of GAD on the pharmacokinetics (PKs) and metabolic enzymes of BBR. PURPOSE: To investigate the pharmacokinetic (PK) and pharmacodynamic (PD) mechanism of the herb-drug interactions (HDIs) between GAD and BBR. STUDY DESIGN AND METHODS: Intragastric single BBR (4.5 or 50 mg/kg), single BBR (4.5 or 50 mg/kg) + single GAD (450 mg/kg, 2 h after BBR-administration), or single BBR (4.5 or 50 mg/kg) + multiple GAD (450 mg/kg/day, once daily for 7 days) were administered to both sexes for BBR PK studies in normal rats. Intragastric multiple BBR (4.5 mg/kg/day), or multiple BBR (4.5 mg/kg/day) + multiple GAD (450 mg/kg/day, 2 h after BBR-administration) were administered for BBR PK and PD studies in male rats with hyperuricemic nephropathy (HN). The cumulative anti-hyperuricemic effects of BBR and BBR+GAD were determined by plasma uric acid (UA) concentration-time curve and area under curve (AUCUA). An in vivo cocktail approach was employed to determine the effects of GAD on cytochrome P450 (CYP) 2C11(9) and 1A2 - mediated drug metabolism. RESULTS: In normal rats, the repeated dose administration of GAD induced a significant increase of BBR AUC and prolonged the mean residence time (MRT) (p < 0.05). systemic exposure to BBR and metabolically derived hydroxybenzbromarones was significantly greater in female compared with male rats (p < 0.05). In HN rats, post-administration of GAD resulted in significantly higher bioavailability and enterohepatic recycling (ER) of BBR relative to the BBR alone administrated group from the prolongation of terminal elimination half-life (T1/2) and MRT of BBR (p < 0.05). Significantly higher urate-lowering effect of BBR+GAD compared with BBR alone was generally observed at post-dosing most time points with a maximal effect of 84.3% (acute treatment), 71.4% (7-day subchronic treatment) and 82.5% (14-day subchronic treatment) reduction in UA levels. Additionally, GAD showed a significant inhibitory effect on CYP2C11(9)-mediated tolbutamide (probe substrate) metabolism with ≥ 1.25 but < 2-fold increase in AUCtolbutamide. CONCLUSIONS: PD synergism demonstrated with the BBR+GAD combination could be explained by the PK interaction observed partially from CYP2C11(9)-mediation and enterohepatic recycling.


Assuntos
Gnaphalium , Interações Ervas-Drogas , Animais , Benzobromarona/farmacologia , Feminino , Masculino , Extratos Vegetais/farmacologia , Ratos , Tolbutamida/farmacocinética
4.
Planta Med ; 88(6): 455-465, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33902131

RESUMO

A new sesquiterpene, chlorantholide G (1: ), a new sesquiterpene dimer, elatiolactone (2: ), and 2 new diterpenes, elatiorlabdane B (3: ) and elatiorlabdane C (4: ), together with 51 known compounds, were isolated from the aerial parts of Chloranthus elatior. The new structures including their absolute configurations were mainly established by mass spectrometric, NMR, and electronic circular dichroism experiments. All isolated compounds were tested for their anti-hDHODH activity. (4S,6R)-4-hydroxy-6-isopropyl-3-methylcyclohex-2-enone (5: ) and (4S,5R,9S,10R)-8(17),12,14-labdatrien-18-oic acid (29: ) were the most active compounds with IC50 values of 18.7 and 30.7 µM, respectively.


Assuntos
Di-Hidro-Orotato Desidrogenase , Sesquiterpenos , Dicroísmo Circular , Humanos , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Estereoisomerismo
5.
Pers Soc Psychol Bull ; 44(4): 521-537, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29226785

RESUMO

People form first impressions from facial appearance rapidly, and these impressions can have considerable social and economic consequences. Three dimensions can explain Western perceivers' impressions of Caucasian faces: approachability, youthful-attractiveness, and dominance. Impressions along these dimensions are theorized to be based on adaptive cues to threat detection or sexual selection, making it likely that they are universal. We tested whether the same dimensions of facial impressions emerge across culture by building data-driven models of first impressions of Asian and Caucasian faces derived from Chinese and British perceivers' unconstrained judgments. We then cross-validated the dimensions with computer-generated average images. We found strong evidence for common approachability and youthful-attractiveness dimensions across perceiver and face race, with some evidence of a third dimension akin to capability. The models explained ~75% of the variance in facial impressions. In general, the findings demonstrate substantial cross-cultural agreement in facial impressions, especially on the most salient dimensions.


Assuntos
Reconhecimento Facial , Percepção Social , Adulto , Povo Asiático , China , Comparação Transcultural , Sinais (Psicologia) , Expressão Facial , Feminino , Humanos , Masculino , Reino Unido , População Branca , Adulto Jovem
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