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1.
RSC Adv ; 14(25): 17724-17732, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38832246

RESUMO

The thermochemical reaction between coking wastewater and gasification-coke is a new way to achieve efficient and clean use of coal and solve the problem of coking wastewater treatment in the Gansu Longdong region. To further investigate the thermochemical reaction characteristics of coking wastewater and gasification-coke, this paper explores the effect of coking wastewater on syngas production from coke gasification at 1000 °C, the degradation effect of organic pollutants in coking wastewater, the thermochemical reactivity of gasification-coke, and the reasons why wastewater promotes coke gasification and wastewater degradation. The results showed that the thermochemical reaction of coking wastewater with gasification-coke not only facilitates the improvement of syngas yield and low-level calorific value but also improves the thermochemical reactivity of gasification-coke. Notably, phenol in coking wastewater plays a major role in promoting the gasification of gasification-coke. During the thermochemical reaction, the organic pollutants in the wastewater were effectively degraded, the degradation rate of CODCr reached more than 85%, and the degradation of organic pollutants reached more than 75%. Phenol water and coking wastewater can not only improve the dispersion of the ash phase on the surface of gasification-coke, effectively inhibiting the sintering and agglomeration of the ash phase in gasification-coke, but also change the type and number of organic functional groups in gasification-coke. Therefore, coking wastewater can promote the gasification of coke. The thermochemical reaction between coke wastewater and gasification-coke can simultaneously promote coke gasification and the degradation of coke wastewater and achieve the resourceful use of coke wastewater.

2.
Mikrochim Acta ; 191(5): 291, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687386

RESUMO

Nanorods assembled 3D microspheres of TiO2/MnO2 were prepared via a simple one-pot hydrothermal approach. The resultant composite material exhibited remarkable electrocatalytic activity for hydrogen peroxide (H2O2) in comparison to each single component. The electrochemical sensor constructed with TiO2/MnO2 exhibited a linear relationship within the range 0.0001-5.6 mmol·L-1 for H2O2. The limit of detection (LOD) and sensitivity for H2O2 were 0.03 µmol·L-1 (S/N = 3) and 316.6 µA (mmol·L-1)-1 cm-2. Moreover, this sensor can be employed to detect trace amount of H2O2 in serum and urine samples successfully, supporting an insight and strategy for a more sensitive electrochemical sensor.

3.
Respirol Case Rep ; 12(4): e01347, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38596251

RESUMO

NK/T-cell lymphoma (NKTCL) is a highly aggressive malignant tumour with a very poor prognosis, which often poses diagnostic difficulties due to the non-specificity of its clinical presentation. NK/T-cell lymphoma with eosinophilic hyperplasia syndrome is extremely rare. This article describes a patient with NKTCL misdiagnosed as vasculitis who presented with sinusitis, abdominal pain, anorexia, and lung shadows. Additionally, the patient exhibited extremely high eosinophilia levels, which led to a further misdiagnosis of eosinophilic granuloma. We describe the clinical features, diagnostic methods and differential diagnosis of lymphoma and highlights the importance of a multidisciplinary approach in accurate diagnosis and treatment.

4.
RSC Adv ; 13(18): 12270-12275, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37091614

RESUMO

Recent advancements in ultra-sensitive detection, particularly the Aggregation Induced Emission (AIE) materials, have demonstrated a promising detection method due to their low cost, real-time detection, and simplicity of operation. Here, coumarin functionalized pillar[5]arene (P5C) and bis-bromohexyl pillar[5]arene (DP5) were successfully combined to create a linear AIE supramolecular pseudorotaxane polymer (PCDP-G). The use of PCDP-G as a supramolecular AIE polymer material for recyclable ultra-sensitive Fe3+ and F- detection is an interesting application of the materials. According to measurements, the low detection limits of PCDP-G for Fe3+ and F- are 4.16 × 10-10 M and 6.8 × 10-10 M, respectively. The PCDP-G is also a very effective logic gate and a material for luminous displays.

5.
Membranes (Basel) ; 12(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36557114

RESUMO

It is a great challenge to design and prepare polymeric membranes with excellent permeability and good rejection. In this study, a modifier of gold nanoparticles for crosslinking and self-assembly by 1,6-hexanedithiol is fabricated and used to modify the polyethersulfone membrane as an additive, which forms a uniform porous membrane by liquid-liquid phase conversion technology. The morphology of the membrane is investigated by scanning electron microscopy (SEM), the change of the hydrophilicity of the membrane surface after modification is measured by the contact angle goniometer, and the performance of the fabricated membrane is measured by evaluating the pure water flux and the rejection ratio of bovine serum albumin. The results indicate that the permeability of the modified membrane has a significant improvement. When the mass fraction of the modifying agent is 5 wt%, the water flux of the modified membrane reaches up to 131.6 L m-2 h-1, and has a good rejection ratio to bovine serum albumin. In short, this work plays an important role in improving the flux of the membrane and maintaining good separation performance.

6.
J Chromatogr Sci ; 60(4): 387-400, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-34136906

RESUMO

An efficient method for simultaneous extraction, purification and determination of six lignans in Schisandra chinensis Baill was developed by employing matrix solid-phase dispersion (MSPD) extraction followed by HPLC-UV determination analysis. Several sorbent and desorption solvent that affected the extraction yield of lignans were investigated; neutral alumina and absolute ethanol were selected as the best dispersing material and desorption agent, respectively. Other extraction conditions for MSPD were optimized as follows: 1:2 of S. chinensis raw material to neutral aluminum oxide mass ratio, 1:30 (g/mL) of sample to absolute ethanol, 2.5 h of desorption time and 50°C of desorption temperature. Under the above conditions, the total extraction yield for six lignans have reached (16.99 ± 0.33) x 103 mg/kg with a higher content of 6.88 ± 0.25% in the extracts. Comparative studies were explored by conducting other six extraction approaches including Soxhlet extraction, heat reflux extraction, smashing tissue extraction, microwave-assisted extraction, ultrasonic-assisted extraction and ultrasonic-microwave synergistic extraction. Results showed MSPD technique not only improved the extraction yield, but also improved the purity of lignans, it can be generalized to more extraction of natural compounds. In addition, the validated HPLC-UV method had been successfully applied to analysis of lignans from 10 real S. chinensis samples.


Assuntos
Lignanas , Schisandra , Cromatografia Líquida de Alta Pressão/métodos , Etanol , Frutas/química , Lignanas/análise , Extratos Vegetais
7.
Zhongguo Zhong Yao Za Zhi ; 46(22): 6004-6010, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34951193

RESUMO

To learn the current situation and strengthen the management of national standards for Chinese medicinal materials, we sorted out the relevant national standards. According to incomplete statistics, there are 1 185 kinds of Chinese medicinal materials, including 1 024 kinds of plant medicines, 106 kinds of animal medicines, and 54 kinds of mineral medicines, in addition to ethnic medicinal materials with different functions. The relevant standards include 819 Pharmacopoeia standards, 342 standards issued by the Ministry of Health or National Medicinal Products Administration, 7 standards for new medicinal materials, and 17 standards for imported medicinal materials. In this paper, the sources of standards as well as the distribution of families and genera and the distribution of medicinal parts of medicinal materials are analyzed. The suggestions are as follows:(1)to improve the coordination among different national standards of Chinese medicinal materials;(2)to improve the standardization and controllability of relevant standards;(3)to revise the issued standards for Chinese medicinal materials(including Tibetan, Uygur, and Mongolian medicinal materials).


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Animais , Povo Asiático , China , Humanos , Medicina Tradicional Chinesa , Padrões de Referência
8.
Chem Biodivers ; 18(6): e2000947, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33848051

RESUMO

The ultrasound-assisted extraction (UAE) parameters of total water-soluble polysaccharides (TABPs) from Acanthopanaxbrachypus fruit were optimized by Box-Behnken design (BBD) and response surface methodology (RSM). Physicochemical, structural, and functional properties of TABPs were investigated by chemical analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), high performance liquid chromatography (HPLC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), water-holding capacity (WHC), oil-holding capacity (OHC), emulsion capacity (EC), emulsion stability (ES), as well as DPPH. and ABTS.+ scavenging assays. The results showed that the maximal UAE-yield of TABPs was 3.81±0.18 % under the optimal conditions (ultrasonic power 325 W, extraction temperature 47 °C, extraction time 22 min). TABPs was rich in some beneficial element (Mg, K, Fe, Zn and Na) but little in harmful elements (Hg, Cd, As and Pb), and displayed rough surface with flake-like features and large dents, contained 93.89±0.08 % of total carbohydrate with more different monosaccharides including glucose, galactose, rhamnose, arabinose, mannose, xylose, and uronic acid in a molar ratio of 8.83 : 7.90 : 4.74 : 4.55 : 2.80 : 2.39 : 1.00, respectively. TABPs exhibited broad weight distribution (11.2-133.5 kDa), excellent thermal stability (>280 °C), WHC (0.61±0.08 g water/g sample) and OHC (4.53±0.12 g oil/g sample), as well as higher EC (43.75±1.23 %) and ES (38.32±1.50 %). Furthermore, TABPs also displayed remarkable scavenging activities on DPPH. and ABTS.+ in vitro. These findings provide a scientific basis for the applications of TABPs in functional additives for food, medicine, and cosmetics.


Assuntos
Antioxidantes/isolamento & purificação , Eleutherococcus/química , Frutas/química , Polissacarídeos/isolamento & purificação , Ondas Ultrassônicas , Antioxidantes/química , Antioxidantes/farmacologia , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Fenômenos Químicos , Tamanho da Partícula , Picratos/antagonistas & inibidores , Polissacarídeos/química , Polissacarídeos/farmacologia , Solubilidade , Ácidos Sulfônicos/antagonistas & inibidores , Água/química
9.
Carbohydr Res ; 487: 107890, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31869572

RESUMO

A water-soluble polysaccharide (ALP) from Acanthopanax leucorrhizus was chemically modified to obtain two sulfated derivatives (S-ALP1 and S-ALP2), two phosphorylated derivatives (P-ALP1 and P-ALP2) and two acetylated derivatives (A-ALP1 and A-ALP2) with different degree of substitution (DS). Their structures were characterized by chemical and spectral (IR, 13C NMR and 31P NMR) analysis, and in vitro antioxidant activity were evaluated by reducing power assay, DPPH• and HO• scavenging assay. The results obtained showed that the modifications were successful, although the molecular weight (Mw) of the ALP derivatives decreased due to slight degradation during the reaction. Physicochemical and antioxidant properties of ALP changed by the chemical modifications, and the type of the substitution group and DS played a decisive role in the antioxidant activity of the derivatives. P-ALP and S-ALP with higher DS displayed stronger antioxidant abilities on scavenging DPPH• and HO•, ferric-reducing power compared with ALP, and exhibited a certain dose-effect relationship, whereas A-ALP were less effective. These results provide a scientific basis for the further studies and utilization of A. leucorrhizus polysaccharides.


Assuntos
Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Eleutherococcus/química , Radical Hidroxila/antagonistas & inibidores , Picratos/antagonistas & inibidores , Polissacarídeos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Configuração de Carboidratos , Peso Molecular , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
10.
Carbohydr Polym ; 196: 359-367, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29891307

RESUMO

A novel water-soluble polysaccharide (named ALP-1) was successfully isolated from the stem barks of Acanthopanax leucorrhizus by hot-water extraction, and further purified by Cellulose DEAE-52 and Sephadex G-100 chromatography. The structure of ALP-1 was characterized by HPLC, HPGPC, partial acid hydrolysis, periodate oxidation, Smith degradation, methylation, together with UV, IR and NMR spectral analysis. The antioxidant activities also were evaluated in vitro. Structural analysis revealed that ALP-1 was a homogeneous galactan with the average molecular weight of 169 kDa, composed of galactose, glucose, mannose and arabinose in a molar ratio of 6.1:2.1:1.1:1.0, owning a backbone structure of 1,6-linked α-d-Galp residues with some branches of α-d-Manp-(1 → 3)-α-l-Araf residues at O-3 and α-d-Galp residues at O-4 of 1,6-linked α-d-Galp. Antioxidant assay showed that ALP-1 exhibited strong DPPH and HO scavenging activities, as well as ferric-reducing antioxidant power. These results provide a scientific basis for the further use of polysaccharides from A. leucorrhizus.

11.
Clin Chim Acta ; 483: 156-163, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29709449

RESUMO

Epithelial-mesenchymal transition (EMT) leads to tumour progression, including tumour metastasis, disease recurrence and therapy resistance. Cancer stem cells (CSCs) are a small group of cells that have the ability to undergo self-renewal and heterogeneous differentiation, which play a key role in the occurrence and development of cancer. EMT can promote tumour cells to develop stem cell characteristics, which makes tumours more difficult to treat. Therefore, exploring the role of EMT and CSCs in the metastasis of cancer is of great significance to guide tumour treatment and prognosis. In this review, we discuss EMT and CSCs in cancer progression and therapeutic resistance, with a special focus on the common characteristics and relationships between these processes, to explore the crucial relationships in the development of improved anti-tumour therapies. AREAS COVERED: In this brief review article, the author has searched PubMed and Wikipedia for original research and reviewed articles to gather current information on the association of CSCs and EMT with therapeutic resistance characteristics, cancer growth and metastasis, which are believed to be regulated by the TGF-ß, Wnt, Hedgehog (Hh), ß-catenin, STAT3, Notch, and Nanog signalling pathways and other factors (miRNAs, microenvironment and additional cytokines).


Assuntos
Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/patologia , Transdução de Sinais , Progressão da Doença , Humanos , Metástase Neoplásica
12.
Fitoterapia ; 124: 167-176, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29128601

RESUMO

Twenty natural stilbenoids (1-20), including seven new stilbenoids (2, 4-7, 19, 20) and thirteen known stilbenoids (1, 3, 8-18), were isolated from the stem barks of Acanthopanax leucorrhizus, and six modified stilbenoid derivatives (1a, 2a, 4a, 4b, 7a and 17a) were obtained via methylation, demethylation and isopentenylation of the corresponding isolates (1, 2, 4, 7 and 17). These stilbenoids were structurally characterized by comprehensive analysis of their spectroscopic data and comparison with literature information, and evaluated for their cytotoxic activities against three human tumor cell lines (leukemia HL-60, hepatoma SMMC-7721 and breast carcinoma MCF-7) in vitro by MTT assay. The results showed that compounds 1a, 4a and 4b showed potent selective cytotoxicity against SMMC-7721 (IC50=10.16±1.95µM and 9.76±1.32µM) and MCF-7 (IC50=10.72±2.78µM) cell lines. The cytotoxic evaluation of these structurally modified stilbenoid derivatives have led to the establishment of a structure-activity relationship.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Eleutherococcus/química , Casca de Planta/química , Estilbenos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
13.
Chem Biodivers ; 14(11)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28805955

RESUMO

A new cis-stilbenoid, 1,9-dihydroxy-10-methoxy-6H-dibenzo[b,f]oxocin-6-one (2) was isolated from the AcOEt extract of the stem barks of Acanthopanax leucorrhizus, along with three known stilbenoids, 9-hydroxy-10-methoxy-6H-dibenzo[b,f]oxocin-6-one (1), 5-O-methyl-(E)-resveratrol 3-O-ß-d-glucopyranoside (3), and (E)-resveratrol 3-O-ß-d-xylopyranoside (4). Two derivatives (2a and 2b) were synthesized by the structural modification of compound 2, which exhibited certain cytotoxic activities against HT-29 and HeLa cell lines in vitro. All compounds were structurally characterized by comprehensive analysis of their spectroscopic data and comparison with literature information, and evaluated for their cytotoxic activities against three human tumor cell lines (HL-60, HT-29, and HeLa) by the standard MTT assay in vitro. The results showed that derivatives 2a and 2b exhibited strong activities than compounds 2 against HT-29 and HeLa cell lines.


Assuntos
Eleutherococcus/química , Estilbenos/química , Sobrevivência Celular/efeitos dos fármacos , Eleutherococcus/metabolismo , Células HL-60 , Células HT29 , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Casca de Planta/química , Casca de Planta/metabolismo , Extratos Vegetais/química , Caules de Planta/química , Caules de Planta/metabolismo , Estilbenos/isolamento & purificação , Estilbenos/toxicidade
14.
Am J Transl Res ; 9(2): 803-811, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28337309

RESUMO

OBJECTIVES: To investigate the effect of gastric motility protein 2 (GKN2) on the proliferation, apoptosis and invasion of gastric cancer cell and on the JAK/signal transducer and activator of transcription 3 (STAT3) signaling pathway. METHODS: Expression of GKN2 was qualified using Western blot analysis in four gastric cancer cell lines and immortalized human gastric mucosal epithelial cell line GES-1. The cells were then transfected with pcDNA3.1-GKN2 and control vector using Lipofectaminetm2000 and assayed for viability, apoptosis, cell cycle changes, invasion ability as well as expression of cell cycle protein D1 (Cylin D1), Bcl-2, Bax, matrix metalloproteinase 2 (MMP2), MMP9, JAK2 and p-STAT3. RESULTS: Western blot analyses showed that the expression of GKN2 was significantly lower in 4 gastric cancer cell lines (BGC-823, SGC-7901, AGS and MKN-45) than in GES-1. Of them, SGC-7901 had the lowest expression. The line was chosen for subsequent transfection experiments. Compared with control (transfection with empty vector), pcDNA3.1-GKN2-transfected cells had significantly more GKN2 protein and mRNA, decreased cell viability, increased apoptosis, more cells arrested at G1 phase and reduced invasiveness. Expression analyses showed that expression of Cyclin D1, Bcl-2, MMP2, MMP9, JAK2 and STAT3 was significantly down-regulated, while Bax was significantly up-regulated. CONCLUSION: Over-expression of GKN2 can increase apoptosis, reduce proliferation and invasion ability of gastric cancer cells as a result of down-regulated JAK2/STAT3 signaling pathway.

15.
Int J Oncol ; 50(2): 697-707, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28101575

RESUMO

Diallyl disulfide (DADS) is a primary component of garlic, which has chemopreventive potential. We previously found that moderate doses (15-120 µM) of DADS induced apoptosis and G2/M phase cell cycle arrest. In this study, we observed the effect of low doses (8 µM) of DADS on human leukemia HL-60 cells. We found that DADS could inhibit proliferation, migration and invasion in HL-60 cells, and arrested cells at G0/G1 stage. Then, cell differentiation was displayed by morphologic observation, NBT reduction activity and CD11b evaluation of cytometric flow. It showed that DADS induced differentiation, reduced the ability of NBT and increased CD11b expression. Likewise, DADS inhibited xenograft tumor growth and induced differentiation in vivo. In order to make sure how DADS induced differentiation, we compared the protein expression profile of DADS-treated cells with that of untreated control. Using high resolution mass spectrometry, we identified 18 differentially expressed proteins after treatment with DADS, including four upregulated and 14 downregulated proteins. RT-PCR and western blot assay showed that DJ-1, cofilin 1, RhoGDP dissociation inhibitor 2 (RhoGDI2), Calreticulin (CTR) and PCNA were decreased by DADS. These data suggest that the effects of DADS on leukemia may be due to multiple targets for intervention.


Assuntos
Compostos Alílicos/administração & dosagem , Antígeno CD11b/metabolismo , Dissulfetos/administração & dosagem , Leucemia/tratamento farmacológico , Proteoma/efeitos dos fármacos , Compostos Alílicos/farmacologia , Animais , Antígeno CD11b/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dissulfetos/farmacologia , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia/genética , Leucemia/metabolismo , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Yao Xue Xue Bao ; 52(2): 258-63, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29979512

RESUMO

This study was designed to explore the impact of depression on kidney-yang deficiency in rats. Rats were repeatedly injected with hydrocortisone for 21 days to establish the depression model with kidneyyang deficiency. Tolbutamide, chlorzoxazone, theophylline, midazolam, omeprazole and dextromethorphan were used as substrates of CYP2C6, CYP2E1, CYP1A2, CYP3A2, CYP2D1, and CYP2D2 to test the depression impact on drug metabolism. Plasma concentrations of six CYP450 were determined by LC-MS/MS and used as pharmacokinetic parameters. Consequently, metabolism of theophylline, chlorzoxazone and tolbutamide were accelerated significantly in the model relative to the control (P < 0.01), but dextromethorphan, omeprazole and midazolam did not exhibit a significant difference. The present study suggests that depression with kidneyyang deficiency had a strong induction of CYP2E1 and moderate induction of CYP1A2, CYP2C6 in the rat model.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Depressão/enzimologia , Fígado/enzimologia , Deficiência da Energia Yang , Animais , Clorzoxazona , Cromatografia Líquida , Dextrometorfano , Hidrocortisona , Midazolam , Omeprazol , Ratos , Espectrometria de Massas em Tandem , Teofilina , Tolbutamida
17.
Int J Biol Macromol ; 93(Pt A): 369-380, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27565299

RESUMO

In this study, optimization of smashing tissue extraction (STE), preliminary chemical characterization and antioxidant activity in vitro of crude polysaccharides (CPS) from Gentiana scabra bge (G. scabra) were investigated. The optimal extraction conditions were determined as follows: sample particle size of 80mesh, solid/liquid ratio of 1:34, extraction voltage of 157.09V and extraction time of 130.38s. Under these conditions, the extraction yield of CPS had reached 15.03±0.14% (n=3). Chemical composition analysis indicated CPS was mainly composed of mannose, rhamnose, galacturonic acid, glcose, galactose, arabinose and fucose in a molar ratio of 1.00:9.89:51.59:35.37:38.06:99.13:21.34, respectively. The average molecular weight of CPS was estimated to be 3.8×104Da. In addition, the potential antioxidant activity of CPS extracted by STE were demonstrated by DPPH radical scavenging assay, superoxide anion radical scavenging assay, hydroxyl radical scavenging assay and ferric reducing power assay. Overall, this study provided an effective extraction technique for G. scabra polysaccharides which would be explored as a promising natural antioxidant agent applied in functional foods or medicines.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Gentiana/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
18.
Clin Chim Acta ; 450: 127-34, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26265233

RESUMO

Trefoil factor family (TFF), composed of TFF1, TFF2, and TFF3, is a cluster of secreted peptides characterized by trefoil domain (s) and C-terminal dimerization domain. TFF1, a gastric tumor suppressor, is a single trefoil peptide originally detected in breast cancer cell lines but expressed mainly in the stomach; TFF2, a candidate of gastric cancer suppressor with two trefoil domains, is abundant in the stomach and duodenal Brunner's glands; and TFF3 is another single trefoil peptide expressed throughout the intestine which can promote the development of gastric carcinoma. According to multiple studies, TFFs play a regulatory function in the mammals' digestive system, namely in mucosal protection and epithelial cell reconstruction, tumor suppression or promotion, signal transduction and the regulation of proliferation and apoptosis. Action mechanisms of TFFs remain unresolved, but the recent demonstration of a GKN (gastrokine) 2-TFF1 heterodimer implicates structural and functional interplay with gastrokines. This review aims to encapsulate the structural and biological characteristics of TFF.


Assuntos
Peptídeos/metabolismo , Neoplasias Gástricas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos/química , Peptídeos/genética , Transporte Proteico , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Fator Trefoil-2
19.
Carbohydr Polym ; 127: 94-100, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25965461

RESUMO

A water-soluble polysaccharide, designated as ABPS-21, was isolated from the stem barks of Acanthopanax brachypus by hot-water extraction and purified by Cellulose DEAE-52 and Sephacryl S-300 HR gel-filtration chromatography, respectively. The homogeneity and molecular weight were determined using HPGPC. The structure was elucidated based on monosaccharide composition and methylation analysis, partial acid hydrolysis, periodate oxidation, Smith degradation, IR and NMR spectroscopy. The result showed that ABPS-21 was a homogeneous heteropolysaccharide including galactose, glucose, rhamnose and galacturonic acid in a molar ratio of 3.0:2.0:2.0:1.0, respectively, with an average molecular weight of 1.06 × 10(5)Da. The main chain of ABPS-21 was made up of → 4)-ß-D-Galp-(1 → 4)-ß-D-Glcp-(1 → 4)-ß-D-Galp-(1 → 4)-ß-D-Galp-(1 → 2)-α-L-Rhap-(1 →, and two side chains α-l-Rhap-(1 → 4)-ß-D-Glcp-(1 → and α-D-galpA-(1 → were attached to the backbone chain at O-6 position of 1,4,6-linked ß-D-Glcp and 1,4,6-linked ß-D-Galp, respectively. ABPS-21, an acidic branched polysaccharide from A. brachypus, was not described up to now.


Assuntos
Eleutherococcus/química , Polissacarídeos/química , Sequência de Carboidratos , Galactose/análise , Glucose/análise , Ácidos Hexurônicos/análise , Dados de Sequência Molecular , Caules de Planta/química , Ramnose/análise
20.
Int J Biol Macromol ; 76: 161-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25661875

RESUMO

A microwave-assisted enzymatic extraction (MAEE) method had been developed, which was optimized by response surface methodology (RSM) and orthogonal test design, to enhance the extraction of crude polysaccharides (CPS) from the fruit of Schisandra chinensis Baill. The optimum conditions were as follows: microwave irradiation time of 10 min, extraction pH of 4.21, extraction temperature of 47.58°C, extraction time of 3h and enzyme concentration of 1.5% (wt% of S. chinensis powder) for cellulase, papain and pectinase, respectively. Under these conditions, the extraction yield of CPS was 7.38 ± 0.21%, which was well in close agreement with the value predicted by the model. The three methods including heat-refluxing extraction (HRE), ultrasonic-assisted extraction (UAE) and enzyme-assisted extraction (EAE) for extracting CPS by RSM were further compared. Results indicated MAEE method had the highest extraction yields of CPS at lower temperature. It was indicated that the proposed approach in this study was a simple and efficient technique for extraction of CPS in S. chinensis Baill.


Assuntos
Frutas/química , Micro-Ondas , Extratos Vegetais/química , Polissacarídeos/química , Schisandra/química , Fracionamento Químico/métodos , Polissacarídeos/ultraestrutura
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