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1.
Foods ; 13(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38890863

RESUMO

The adsorption characteristics of ß-glucooligosaccharides on activated carbon and the purification were systematically investigated. The maximum adsorption capacity of activated carbon reached 0.419 g/g in the optimal conditions. The adsorption behavior was described to be monolayer, spontaneous, and exothermic based on several models' fitting results. Five fractions with different degrees of polymerization (DPs) and structures of ß-glucooligosaccharides were obtained by gradient ethanol elution. 10E mainly contained disaccharides with dp2a (G1→6G) and dp2b (G1→3G). 20E possessed trisaccharides with dp3a (G1→6G1→3G) and dp3b (G1→3G1→3G). 30E mainly consisted of dp3a and dp4a (G1→3G1→3(G1→6)G), dp4b (G1→6G1→3G1→3G), and dp4c (G1→3G1→3G1→3G). In addition to tetrasaccharides, 40E and 50E also contained pentasaccharides and hexasaccharides with ß-(1→3)-linked or ß-(1→6)-linked glucose residues. All fractions could inhibit the accumulation of intracellular reactive oxygen species (ROS) in H2O2-induced Caco-2 cells, and they could improve oxidative stress damage by increasing the activity of superoxide dismutase (SOD) and reduced glutathione (GSH), which were related to their DPs and structures. 50E with high DPs showed better anti-oxidative stress activity.

2.
Carbohydr Res ; 538: 109100, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38555657

RESUMO

A recombinant exo-α-mannosidase from Solitalea canadensis (Sc3Man) has been characterized to exhibit strict specificity for hydrolyzing α1,3-mannosidic linkages located at the non-reducing end of glycans containing α-mannose. Enzymatic characterization revealed that Sc3Man operates optimally at a pH of 5.0 and at a temperature of 37 °C. The enzymatic activity was notably enhanced twofold in the presence of Ca2+ ions, emphasizing its potential dependency on this metal ion, while Cu2+ and Zn2+ ions notably impaired enzyme function. Sc3Man was able to efficiently cleave the terminal α1,3 mannose residue from various high-mannose N-glycan structures and from the model glycoprotein RNase B. This work not only expands the categorical scope of bacterial α-mannosidases, but also offers new insight into the glycan metabolism of S. canadensis, highlighting the enzyme's utility for glycan analysis and potential biotechnological applications.


Assuntos
Bacteroidetes , Manose , Polissacarídeos , alfa-Manosidase/química , alfa-Manosidase/metabolismo , Manose/química , Polissacarídeos/química , Íons , Manosidases/metabolismo
3.
Org Lett ; 16(17): 4504-7, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25140818

RESUMO

An efficient combination between the Passerini three-component reaction and aldol condensation has been developed for the synthesis of bicyclic isocoumarins with different substituted patterns via solvent-dependent domino pathways. These two operationally friendly methods simultaneously install C-O and C-C bonds in a one-pot manner, allowing the utilization of low-cost and readily accessible 2-formylbenzoic acid, isocyanides, and arylglyoxals. Mechanisms of formation of different substituted isocoumarin derivatives are also proposed.


Assuntos
Isocumarinas/síntese química , Aldeídos/química , Catálise , Cianetos/química , Isocumarinas/química , Estrutura Molecular , Estereoisomerismo
4.
ACS Comb Sci ; 16(6): 281-6, 2014 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-24588380

RESUMO

An efficient, three-component strategy for the improved synthesis of multifunctionalized 6,7-dihydrobenzofuran-4(5H)-ones under microwave irradiation in ethyl alcohol within short periods has been established. The synthesized benzofuran-4(5H)-ones have been readily converted into polyfunctionalized cinnoline-4-carboxamides by treating with hydrazine hydratein in the same solvent through a regioselective ring-opening of the furan. Tedious workup procedures can be avoided because of the direct precipitation of products from the reaction solution by water addition, thus rendering the two-steps process ecofriendly.


Assuntos
Benzofuranos/síntese química , Polímeros/síntese química , Benzofuranos/química , Modelos Moleculares , Estrutura Molecular , Polímeros/química
5.
Lung ; 188(6): 469-74, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20668869

RESUMO

Serum cell-free DNA concentrations have been reported to increase in many acute diseases as well as in some chronic conditions such as cancer and autoimmune diseases. The aim of this study was to examine whether serum DNA concentrations were elevated in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). The effects of nasal continuous positive airway pressure (nCPAP) on serum DNA were also investigated. One hundred twenty-seven people diagnosed with OSAHS by polysomnography (PSG) were admitted into the OSAHS group, and 52 subjects without OSAHS were recruited for the control group. The OSAHS group was further divided into mild, moderate, and severe OSAHS subgroups based on their apnea-hypopnea index (AHI) during sleep. Ten patients with moderate and severe OSAHS were treated with nCPAP. Serum DNA, interleukin-6 (IL-6), and malonaldehyde (MDA) concentrations were measured and were found to be significantly higher in patients with moderate and severe OSAHS groups than those in the mild OSAHS and control groups (p < 0.05). Univariate analysis showed that serum DNA correlated positively with AHI, oxygen desaturation index (ODI), IL-6, and MDA, and negatively correlated with minimal oxygen saturation (miniSaO(2)) (all p < 0.05). In stepwise multiple regression analysis, only MDA and miniSaO(2) were suggested as significant independent predictors for the serum DNA concentrations. After 6 months of nCPAP therapy, serum concentrations of DNA, IL-6, and MDA were significantly decreased (p < 0.05). The increasing concentration of serum DNA in patients with OSAHS was positively correlated with disease severity. Serum DNA may become an important parameter for monitoring the severity of OSAHS and effectiveness of therapy.


Assuntos
DNA/sangue , Apneia Obstrutiva do Sono/genética , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , China , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Humanos , Interleucina-6/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Polissonografia , Estudos Prospectivos , Análise de Regressão , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/terapia , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 32(12): 926-30, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20193354

RESUMO

OBJECTIVE: To investigate whether there was a correlation between lipid level, hemorheology and the obstructive sleep apnea hypopnea syndrome. METHODS: Two hundred and thirty-one subjects in our sleep respiratory disease center between 2006 and 2009 were included. Eighty nine were obese OSAHS subjects, 62 were non-obese OSAHS subjects, 40 were obese subjects without OSAHS (obese group) and 40 were non-obese subjects without OSAHS (control group). We examined and compared the lipid profile and hemorheology in all subjects. RESULTS: In obese OSAHS group, the levels of triglyceride (TG) [(2.74 +/- 2.02) mmol/L], cholesterol (TC) [(5.14 +/- 0.96) mmol/L] were higher and HDL [(1.13 +/- 0.36) mmol/L], apoA-I [(1.20 +/- 0.20) mmol/L] were lower, compared to the non-obese OSAHS group (F = 7.77, 7.99, all P < 0.01). The level of the whole blood viscosity in obese OSAHS group was significantly higher than that in non-obese OSAHS group (F = 8.81-11.99, P < 0.05). There was no significant difference in blood lipid levels among the 2 study groups:non-obese OSAHS and control group, obese OSAHS and obese group (F = 6.42 - 11.99, P > 005). The levels of the whole blood viscosity and HCT were significantly higher in non-obese OSAHS group than in control group (F = 0.41 - 2.23, P < 0.05); obese OSAHS group were higher than obese group (F = 0.12 - 2.10, P < 0.05). No significant difference in blood lipid levels was noted among the 4 non-obese groups with different disease severity; similar result was also observed among obese OSAHS groups. CONCLUSIONS: Obesity is responsible for dyslipidemia in OSAHS. OSAHS has no significant correlation with lipid abnormalities, but it significantly correlates with hemorheology disorder.


Assuntos
Hemorreologia , Apneia Obstrutiva do Sono , Humanos , Lipídeos , Obesidade , Sono
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