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1.
Biochem Biophys Res Commun ; 557: 228-235, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33887588

RESUMO

LncRNA-cCSC1 is highly expressed in colorectal cancer (CRC). The study was designed to evaluate the function and mechanism of lncRNA-cCSC1 in cell proliferation of CRC. RT-PCR was used to measure the expression levels of lncRNA-cCSC1 in CRC cell lines. CCK-8, colony formation, EdU staining, flow cytometry and Western blot were performed to examine the effect of interference with lncRNA-cCSC1 expression on cell proliferation. miR-124-3p and the target genes of miR-124-3p were investigated using bioinformatics analysis and verified by dual-luciferase reporter, RT-PCR and Western blot. Rescue experiments were carried out to confirm the role of miR-124-3p in cell proliferation of CRC. Our results showed that cell proliferation of CRC was promoted by lncRNA-cCSC1 upregulation and inhibited by lncRNA-cCSC1 downregulation. In addition, miR-124-3p is predicted to be the target of lncRNA-cCSC1 and is negatively correlated with lncRNA-cCSC1. Moreover, the addition of miR-124-3p mimics or inhibitor reversed the effects induced by lncRNA-cCSC1 overexpression or silencing on cell proliferation of CRC. Additionally, lncRNA-cCSC1 regulated the expression level of CD44, a target gene of miR-124-3p. Finally, we studied the effects of the lncRNA-cCSC1/miR-124-3p axis on CD44. These results indicate that lncRNA-cCSC1 promotes cell proliferation of CRC through sponging miR-124-3p and upregulating CD44.


Assuntos
Adenocarcinoma/metabolismo , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Receptores de Hialuronatos/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Bases de Dados Genéticas , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Receptores de Hialuronatos/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Regulação para Cima
2.
Nutr Cancer ; 69(7): 1011-1018, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28937797

RESUMO

PURPOSE: To explore whether the modified-nutrition index (m-NI) is a prognostic factor for the overall survival (OS) in nasopharyngeal carcinoma (NPC) patients who undergo intensity-modulated radiotherapy (IMRT). METHODS: Clinical data were prospectively collected from NPC patients who underwent IMRT at our hospital between October 2008 and December 2014. The patient nutritional status before radiotherapy was evaluated using the m-NI, based on eight nutrition indicators including body mass index, arm muscle circumference, albumin, total lymphocyte count, red blood cell count, hemoglobin, serum pre-albumin, and transferrin. The independent prognostic value of m-NI for the OS was evaluated. RESULTS: A total of 323 patients (229 males, 94 females) were included in this study, and the follow-up rate was 99.7% (322/323). The 1-, 3-, and 5-yr OS rates between malnutrition and normal nutrition groups by using the m-NI were 93.0% vs. 96.9%, 76.4% vs. 82.8%, and 61.8% vs. 77.1%, respectively. A regression analysis showed that the m-NI was the significant prognostic value for the OS in NPC. CONCLUSIONS: The m-NI before radiotherapy is a significant prognostic factor for the OS in NPC patients. Further validation of our instrument is needed in other NPC patients.


Assuntos
Carcinoma/mortalidade , Carcinoma/radioterapia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/radioterapia , Estado Nutricional/fisiologia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Carcinoma/tratamento farmacológico , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Avaliação Nutricional , Prognóstico , Estudos Prospectivos , Radioterapia de Intensidade Modulada , Taxa de Sobrevida , Adulto Jovem
3.
Prep Biochem Biotechnol ; 47(9): 860-866, 2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-28636483

RESUMO

Lumping kinetics models were built for the biological treatment of acetone-butanol-ethanol (ABE) fermentation wastewater by oleaginous yeast Trichosporon cutaneum with different fermentation temperatures. Compared with high temperature (33°C, 306 K) and low temperature (23°C, 296 K), medium temperature (28°C, 301 K) was beneficial for the cell growth and chemical oxygen demand (COD) degradation during the early stage of fermentation but the final yeast biomass and COD removal were influenced little. By lumping method, the materials in the bioconversion network were divided into five lumps (COD, lipid, polysaccharide, other intracellular products, other extracellular products), and the nine rate constants (k1-k9) for the models can well explain the bioconversion laws. The Gibbs free energy (G) for this bioconversion was positive, showing that it cannot happen spontaneous, but the existence of yeast can after the chemical equilibrium and make the bioconversion to be possible. Overall, the possibility of using lumping kinetics for elucidating the laws of materials conversion in the biological treatment of ABE fermentation wastewater by T. cutaneum has been initially proved and this method has great potential for further application.


Assuntos
Acetona/metabolismo , Butanóis/metabolismo , Etanol/metabolismo , Trichosporon/fisiologia , Águas Residuárias/microbiologia , Análise da Demanda Biológica de Oxigênio , Fermentação , Cinética , Metabolismo dos Lipídeos
4.
Nutr Cancer ; 68(1): 63-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26709739

RESUMO

We aimed to assess the effect of chemoradiotherapy on the nutritional status of patients with nasopharyngeal cancer (NPC) and to detect the risk factors for poor nutrition status in NPC patients after radiotherapy. A total of 104 NPC patients participated in this clinical observational study. Psychological distress and nutritional indicators were measured prior to chemoradiotherapy. During the course of radiation therapy, side effect symptoms were assessed weekly. At the end of radiotherapy, nutritional indicators were measured again. Logistic regression was used to identify the risk factors for poor nutritional status after radiotherapy. The values of the 9 nutritional indicators were significantly lower after radiotherapy (P < 0.001) than the initial values before treatment. After radiotherapy, 20.19% of patients had more than 10% weight loss. At a significance level of α = 0.05, the risk factors for poor nutritional status were old age (P = 0.042), female gender (P < 0.001), late stage of the disease (P = 0.013), depression (P = 0.024), high side effect score (P = 0.007), and moderate nutritional status before radiotherapy (P = 0.015). Radiotherapy affects the nutritional status of NPC patients. To prevent malnutrition during radiotherapy, nutritional assessment and intervention should be an integral part of treatment.


Assuntos
Quimiorradioterapia , Neoplasias Nasofaríngeas/terapia , Estado Nutricional , Adulto , Idoso , Ansiedade/etiologia , Quimiorradioterapia/efeitos adversos , Feminino , Humanos , Modelos Logísticos , Masculino , Desnutrição/etiologia , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/psicologia
5.
Chem Pharm Bull (Tokyo) ; 64(8): 1208-17, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27238362

RESUMO

A new iron(III) complex (1) of 5-nitro-8-hydroxylquinoline (HNOQ) was synthesized and structurally characterized in its solid state and solution state by IR, UV-Vis, electrospray ionization (ESI)-MS, elemental analysis, conductivity and X-ray single crystal diffraction analysis. The DNA binding study suggested that complex 1 interacted with calf thymus (ct)-DNA mainly via an intercalative binding mode. By 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the in vitro cytotoxicity of complex 1, comparing with HNOQ and cisplatin, was screened towards a series of tumor cell lines as well as the normal liver cell line HL-7702. Complex 1 showed higher cytotoxicity towards the tested tumor cell lines but lower cytotoxicity towards HL-7702 than HNOQ, in which the T-24 was the most sensitive cell line for 1. Complex 1 caused G2 phase cell cycle arrest and induced cell apoptosis in T-24 cells in a dose-dependent mode, evidenced by changes in cell morphology. Targeting the mitochondrial pathway due to the redox potential of Fe(III)/Fe(II), the apoptotic mechanism in T-24 cells treated by 1 was investigated by reactive oxygen species (ROS) detection, intracellular [Ca(2+)] measurement and caspase-9 and caspase-3 activity assay. It suggested that complex 1 induced cell apoptosis by triggering the caspase-9 and caspase-3 activation via a mitochondrion-mediated pathway.


Assuntos
Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Ferro/química , Quinolinas/química , Quinolinas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Cálcio/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Bovinos , Linhagem Celular , Cisplatino/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Cristalografia por Raios X , DNA/química , DNA/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Conformação Molecular , Espécies Reativas de Oxigênio/metabolismo , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
6.
Indian J Microbiol ; 56(1): 72-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26843699

RESUMO

To evaluate the possibility of Bacterial cellulose/Inorganic Gel of Bentonite (BC/IGB) composite production using in situ method, the BC/IGB composite was successfully produced by in situ modification of BC in both HS medium and corncob hydrolysate. The results showed that the BC/IGB composite obtained in HS medium (one classical medium for BC production) had a higher water holding capacity, but the water retention capacity of the BC/IGB composite obtained in corncob hydrolysate was better. The performance of BC/IGB composite depended on the environment of in situ modification. Using different media showed significant influence on the sugar utilization and BC yield. In addition, BC/IGB composite produced by in situ method was compared with that produced by ex situ method, and the results shows that water holding capacity of BC/IGB composite obtained through in situ method was better. XRD results showed the crystallinity of BC/IGB composite related little to its performance as water absorbent. Overall, in situ modification is appropriate for further production of BC composite and other clay materials.

7.
Support Care Cancer ; 23(5): 1401-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25370891

RESUMO

PURPOSE: This study was designed to detect the prevalence of poor sleep quality in cervical cancer patients before and after adjuvant therapy, determine whether the prevalence of poor sleep quality in cervical cancer patients is higher than that in the general population, and analyze the factors associated with poor sleep quality. METHODS: A total of 76 stages I and II cervical cancer patients and 116 female residents completed the Pittsburgh Sleep Quality Index (PSQI). Patient Neurotoxicity Questionnaire (PNQ), Distress Thermometer (DT), Multidimensional Fatigue Inventory, and Hospital Anxiety and Depression Scale were used to measure the patients' chemotherapy-induced peripheral neurotoxicity (CIPN), psychological distress, fatigue, anxiety, and depression. Data on social support and exercise were collected by the questionnaire. Logistic regression was used to identify the factors associated with poor sleep quality. RESULTS: Prevalence rates of poor sleep quality were 27.59 % for female residents, 52.63 % for patients before adjuvant therapy, and 64.50 % for patients after adjuvant therapy. The distributions of the PSQI scores of the patients before (Z = 3.814, P < 0.001) and after (Z = 5.957, P < 0.001) adjuvant therapy were different from those of the residents. The difference in the PSQI scores before and after adjuvant therapy among cervical cancer patients was significant (P = 0.007). The factors associated with poor sleep quality were high DT score (P = 0.045), depression (P = 0.028), anxiety (P = 0.027), high PNQ grade (P = 0.016), and chemotherapy + radiotherapy treatment (P = 0.017). Exercise was a protective factor for poor sleep quality (P =0.019). CONCLUSION: The prevalence of poor sleep quality in stages I and II cervical cancer patients was approximately twice than that of women in the communities. Cancer treatment considerably affected sleep quality. Psychological distress, depression, anxiety, and high grade of CIPN during adjuvant therapy were factors associated with poor sleep quality. Exercise during adjuvant therapy could reduce the risk of poor sleep quality.


Assuntos
Qualidade de Vida/psicologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/psicologia , Sono/fisiologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/psicologia , Adulto , Idoso , Ansiedade/epidemiologia , Quimioterapia Adjuvante/efeitos adversos , Quimioterapia Adjuvante/psicologia , Terapia Combinada , Depressão/psicologia , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Prevalência , Apoio Social , Inquéritos e Questionários
8.
J Mol Model ; 30(2): 26, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191945

RESUMO

CONTEXT: The reaction between Na and HF is a typical harpooning reaction which is of great interest due to its significance in understanding the elementary chemical reaction kinetics. This work aims to investigate the detailed reaction mechanisms of sodium with hydrogen fluoride and the adsorption of HF on the resultant NaF as well as the (NaF)4 tetramer. The results suggest that the reaction between Na and HF leads to the formation of sodium fluoride salt NaF and hydrogen gas. Na interacts with HF to form a complex HF···Na, and then the approaching of F atom of HF to Na results in a transition state H···F···Na. Accompanied by the broken of H-F bond, the bond forms between F and Na atoms as NaF, then the product NaF is yielded due to the removal of H atom. The resultant NaF can further form (NaF)4 tetramer. The interaction of NaF with HF leads to the complex NaF···HF; the form I as well as II of (NaF)4 can interact with HF to produce two complexes (i.e., (NaF)4(I-1)···HF, (NaF)4(I-2)···HF, (NaF)4(II-1)···HF and (NaF)4(II-2)···HF), but the form III of (NaF)4 can interact with HF to produce only one complex (NaF)4(III)···HF. These complexes were explored in terms of noncovalent interaction (NCI) and quantum theory of atoms in molecules (QTAIM) analyses. NCI analyses confirm the existences of attractive interactions in the complexes HF···Na, NaF···HF, (NaF)4(I-1)···HF, (NaF)4(I-2)···HF, (NaF)4(II-1)···HF and (NaF)4(II-2)···HF, and (NaF)4(III)···HF. QTAIM analyses suggest that the F···Na interaction forms in the HF···Na complex while the F···H hydrogen bonds form in NaF···HF, (NaF)4(I-1)···HF, (NaF)4(I-2)···HF, (NaF)4(II-1)···HF and (NaF)4(II-2)···HF, and (NaF)4(III)···HF complexes. Natural bond orbital (NBO) analyses were also applied to analyze the intermolecular donor-acceptor orbital interactions in these complexes. These results would provide valuable insight into the chemical reaction of Na and HF and the adsorption interaction between sodium fluoride salt and HF. METHODS: The calculations were carried out at the M06-L/6-311++G(2d,2p) level of theory which were performed using the Gaussian16 program. Intrinsic reaction coordinate (IRC) calculations were carried out at the same level of theory to confirm that the obtained transition state was true. The molecular surface electrostatic potential (MSEP) was employed to understand how the complex forms. Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) analysis was used to know the topology parameters at bond critical points (BCPs) and intermolecular interactions in the complex and intermediate. The topology parameters and the BCP plots were obtained by the Multiwfn software.

9.
Appl Biochem Biotechnol ; 195(11): 6537-6556, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36877441

RESUMO

The efficient and economical removal of fermentation inhibitors from the complex system of biomass hydrolysate was one of the basics and keys in bio-chemical transformation. In this work, post-cross-linked hydrophilic-hydrophobic interpenetrating polymer networks (PMA/PS_pc IPNs and PAM/PS_pc IPNs) were proposed to remove fermentation inhibitors from sugarcane bagasse hydrolysate for the first time. PMA/PS_pc and PAM/PS_pc IPNs can obviously enhance the adsorption performance towards fermentation inhibitors due to their higher surface area and hydrophilic-hydrophobic synergetic surface properties, especially PMA/PS_pc IPNs has higher selectivity coefficients of 4.57, 4.63, 4.85, 16.0, 49.43, and 22.69, and higher adsorption capacity of 24.7 mg/g, 39.2 mg/g, 52.4 mg/g, 9.1 mg/g, 13.2 mg/g, and 144.9 mg/g towards formic acid, acetic acid, levulinic acid (LA), 5-hydroxymethylfurfural (HMF), furfural, and acid-soluble lignin (ASL), respectively, in a lower total sugar loss of 2.03%. The adsorption kinetics and isotherm of PMA/PS_pc IPNs were studied to elucidate its adsorption behavior towards fermentation inhibitors. In addition, the cyclic utilization property of PMA/PS_pc IPNs was stable. Synthesizing PMA/PS_pc IPNs is a new strategy to provide an efficient adsorbent for the removal of fermentation inhibitors from lignocellulosic hydrolysate.


Assuntos
Celulose , Saccharum , Celulose/metabolismo , Polímeros , Fermentação , Saccharum/química , Hidrólise
10.
Hum Vaccin Immunother ; 18(7): 2153535, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36503415

RESUMO

China has regulated its hepatitis B vaccination policy. However, data on the prevalence of hepatitis B virus (HBV) infection have not been updated since 2014. In addition, the impact of the policy on awareness of hepatitis B is limited, especially in Fujian Province where HBV infection is highly prevalent. We conducted a sero-epidemiological survey in five national monitoring counties to address these concerns. A total of 5,873 subjects were included and classified into four birth cohorts according to the policy time nodes (1981, 1992, and 2002). The HBsAg carrier rate for the general population was 8.6% (95% confidence interval [CI]: 7.9-9.3). Compared with those born before 1981, adjusted odds ratios (OR) for HBV infection were 0.51 (95% CI: 0.43-0.62), 0.10 (0.08-0.12), and 0.015 (0.01-0.023) among the 1981-1991, 1992-2001, and ≥2002 birth cohorts, respectively; while the OR was 1.26 (1.00-1.57), 0.39 (0.26-0.58), and 0.019 (0.006-0.06) for HBsAg carriage, respectively. Among the 4865 residents aged ≥15 years, hepatitis B awareness has been declining since the introduction of the hepatitis B vaccine into the immunization program (ß = -0.25, SE = 0.08, P = .001, and ß = -0.20, SE = 0.08, P = .017 for 1992-2001 and ≥2002 birth cohort, respectively). This decline was obvious for the initiation time of the first dose of the hepatitis B vaccine. Although the hepatitis B vaccination policies have helped reduce the infection, the awareness has declined. More measures on the target population are warranted to improve the public's awareness of hepatitis B vaccination in the context of great achievements.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B , Humanos , Vacinas contra Hepatite B , Hepatite B/prevenção & controle , Vírus da Hepatite B , Anticorpos Anti-Hepatite B , Vacinação , Políticas , China/epidemiologia
11.
Bioresour Technol ; 318: 124053, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32942092

RESUMO

Economical removal of fermentation inhibitors from lignocellulosic hydrolysate plays a considerable role in bioconversion of lignocellulose biomass. In this work, the textural properties of polyacrylamide/polystyrene interpenetrating polymer networks (PAM/PS IPNs) on adsorption of fermentation inhibitors from sugarcane bagasse hydrolysate (SCBH) were investigated for the first time. The results showed that, the specific surface area, pore diameter and surface polarity had important influence on its adsorption performance towards sugars, organic acids, furans and acid-soluble lignin. The PAM/PS IPNs under the optimal copolymerization situation achieved the high selectivity coefficients of 4.07, 14.9, 21.2 and 25.8 with respective to levulinic acid, furfural, hydroxymethylfurfural (HMF) and acid-soluble lignin, and had a low total sugar loss of 2.09%. Overall, this research puts forward a design and synthetic strategy for adsorbent to remove fermentation inhibitors from lignocellulosic hydrolysate.


Assuntos
Saccharum , Resinas Acrílicas , Adsorção , Celulose , Fermentação , Hidrólise , Lignina/metabolismo , Polímeros , Poliestirenos , Saccharum/metabolismo
12.
RSC Adv ; 10(35): 20960-20971, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35692714

RESUMO

The photoelectric conversion efficiency of perovskite solar cells has improved rapidly, but their stability is poor, which is an important factor that restricts their commercial production. This paper studies the physical and chemical stability of perovskite solar cells based on first principles. It is well known that methylamido lead iodide compounds and methylamino lead iodide compounds are easily degraded into NH2CH[double bond, length as m-dash]NH2I, CH3NH3I and PbI2. First, the chemical stability of the above two perovskite-type solar cell materials is discussed by calculating the binding energy. Then, their phonon scattering lines, state density and thermodynamic properties are calculated and analyzed, and the work functions of different types of crystals along different planes such as [1 0 0], [0 1 0 0], [0 0 1] and [1 1 1] are calculated. The results show that the work function of the methylamine iodized lead compound is greater than that of the methylamidine iodized lead compound, which means that the electrons of the methylamidine iodized lead compound escape more easily and the carrier transfer efficiency is higher under the same conditions. Finally, the effects of different temperatures, different electric fields and light on the two kinds of crystal materials are analyzed. This provides theoretical guidance for us to improve the stability of perovskite materials experimentally.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(11): 3052-6, 2009 Nov.
Artigo em Zh | MEDLINE | ID: mdl-20101984

RESUMO

In the present work, the interaction of catechin with bovine serum albumin (BSA) under physiological condition was studied by fluorescence quenching spectra in combination with Fourier transform infrared (FTIR) spectroscopy. The binding constants, the drug-binding mode, the binding site between catechin and BSA in aqueous solution at pH 7.40, and the effect of common ions were studied. The results show that catechin has the ability to quench the intrinsic fluorescence of BSA because of a complex formed, and the quenching mechanism is static quenching. The binding constants K under 296, 303 and 310 K were 2.368, 2.249 and 2.152 x 10(6) L x mol(-1) respectively. The thermodynamic parameters showed that the interaction between catechin and BSA was driven mainly by hydrophobic force and electrostatic interaction. The displacement experiment shows that catechin can bind to the site I of BSA. The distance between the 214 tryptophan residues in BSA and catechin was estimated to be 1.46 nm using Foster's equation on the basis of fluorescence energy transfer. According to FTIR, the secondary structure of BSA changed when catechin was added.


Assuntos
Catequina/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Estrutura Secundária de Proteína , Triptofano/química
14.
Polymers (Basel) ; 10(7)2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30960627

RESUMO

Cellulose-based superabsorbent was synthesized by bacterial cellulose (BC) grafting acrylic acid (AA) in the presence of N,N'-methylenebisacrylamide (NMBA) as a crosslinker and ammonium persulfate (APS) as an initiator. The influence of different factors on composite synthesis, including the weight ratio of the monomer to BC, initiator content, crosslinker content, AA neutralization degree, reaction temperature, and reaction time on the water absorbency of the composite, were systematically learned. Under the optimized conditions, the maximum water absorbency of the composite was 322 ± 23 g/g distilled water. However, the water absorbency was much less for the different salt solutions and the absorption capacity of the composite decreased as the concentration of the salt solutions increased. The pH value had a significant influence on water absorption performance, and with the increase of temperature, the water retention rate of the composite decreased. Additionally, the structure of this composite was characterized with nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The results of NMR and FT-IR provided evidence that the composite was synthesized by BC and AA, and the microstructure showed that it had good performance for water absorption. In addition, the composite possessed suitable thermal stability, and that it could be used in a few high-temperature environments. Overall, this composite is promising for application in water absorption.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(2): 346-9, 2007 Feb.
Artigo em Zh | MEDLINE | ID: mdl-17514973

RESUMO

The aim of the present work is to study the role of polyaccharide and flavone compounds of Flos lonicerae, Ganoderma lucidum etc. in protecting DNA with EB as a probe to determine the fluorescence integration intensity of DNA and EB mixture. D is defined as the interaction constant between different extracts from traditional Chinese herbs and DNA. The bigger the D, the stronger the interaction of drugs and DNA. According to the definition of D, the impact of polysaccharide and flavone compounds on the protection of DNA is discussed. The results show that all the extracts from traditional Chinese herbs can interact with DNA, but the degree of interaction is different. The order is as follows: folium hippophae rhamnosides > rhizoma anemarrhenae > radix acanthopanacis senticosi > Ganoderma lucidum > radix achyranthis bidentatae > fructus lycii > Flos lonicerae > rhizoma atractylodis > Astragalus membranaceus > Flos chrysanthemi in the presence of polysaccharide compounds, while folium hippophae rhamnosides > Flos lonicerae > fructus lycii > rhizoma atractylodis > Astragalus membranaceus > rhizoma anemarrhenae > radix acanthopanacis senticosi > Ganoderma lucidum > radix achyranthis bidentatae (Flos chrysanthemi, with no signals) in the presence of flavone compounds.


Assuntos
DNA/análise , Medicamentos de Ervas Chinesas/química , Flavonas/química , Corantes Fluorescentes/análise , Polissacarídeos/química , Corantes Fluorescentes/química
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(3): 547-51, 2007 Mar.
Artigo em Zh | MEDLINE | ID: mdl-17554919

RESUMO

A natural product, sorghum pigment, consists of a number of important flavonoid derivatives, occurrs on the seed capsules or in the stems of many sorghums, and is widely applied in different fields of food, cosmetic and dyeing industries, It is important for scavenging hydroxyl free radicals and protection of human healthiness. Scavenging capacities of hydroxyl free radicals with sodium nitrite, quercetin and sorghum pigment were comparatively researched by fluorimetry, and the model of hydroxyl free radicals produced is based on the reaction of Cu2+ -catalyzed oxidation of ascorbic acid in the presence of hydrogen peroxide. The hydroxyl radicals react with benzoic acid, forming a fluorescent product, and the fluorescence intensity was determined by the concentration of hydroxybenzoic acid. The experimental results show that the sodium nitrite, quercetin and sorghum pigment have a quantity-effect relationship for scavenging hydroxyl free radicals, and sodium nitrite and quercetin in comparison with sorghum pigment have high antioxidant capacity. Finally, the quenching mechanisms were explored with sodium nitrite, sorghum pigment, and quercetin respectively. The sorghum pigment and sodium nitrite feature a dynamic quenching processes, while quercetin shows a static quenching processes. A reference method was provided for reasonable exploitation and utilization of sorghum pigment.


Assuntos
Corantes/análise , Sequestradores de Radicais Livres/análise , Radical Hidroxila/química , Sorghum/química , Espectrometria de Fluorescência/métodos , Catálise , Corantes/química , Sequestradores de Radicais Livres/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Oxirredução
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(11): 2294-8, 2007 Nov.
Artigo em Zh | MEDLINE | ID: mdl-18260417

RESUMO

The interaction of two kinds of sulfated chitosans with DNA was investigated using fluorescence spectra, absorption spectra, alkaline denaturation curves, ionic strength, fluorescence quenching etc. The results showed that there were two modes of the interaction between sulfated chitosans and DNA/ ethidium bromide (EB): intercalative and electrostatic binding. Hyperchromic and bathochromic effects in the absorption spectra were observed when sulfated chitosans with a low degree of substitution (CT-L) or a high degree of substitution (CT-L) were bound to herring sperm DNA. The stability of DNA/EB was increased with the increase in alkaline denaturation pH in the presence of CT-H and CT-L. Meanwhile, a weak interaction of cationic Mg2+ and phosphate groups of DNA by electrostatic force binding was observed. The fluorescence was efficiently quenched in the presence of a micro-amounts of sulfated chitosans, which confirmed that there was a strong competitive binding interaction among EB, CT-H or CT-L and DNA. All of these demonstrated that different sulfated chitosans can be used as a type of hopeful target-pointed molecule of gene therapy.


Assuntos
Quitosana/química , DNA/química , Animais , Etídio/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
18.
Zhong Xi Yi Jie He Xue Bao ; 5(4): 392-7, 2007 Jul.
Artigo em Zh | MEDLINE | ID: mdl-17631801

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of Dinggui Oil Capsule in treating irritable bowel syndrome (IBS) with stagnation of qi and cold. METHODS: A prospective, randomized, placebo-controlled, double-blind clinical study was undertaken. One hundred and ninety-eight patients with IBS and syndrome of stagnation of qi and cold were randomly divided into high-dose Dinggui Oil group (DGO-H, 1.2 g, 3 times daily; n=66), low-dose Dinggui Oil group (DGO-L, 0.8 g, 3 times daily, n=66), and placebo group (placebo, 5.0 g, 3 times daily, n=66). Patients in the three groups were all treated for 2 weeks. RESULTS: The total significant effective rates for IBS were 54.1%, 28.8% and 21.9% in the DGO-H, DGO-L, and placebo groups, and the total effective rates for the syndrome of stagnation of qi and cold were 54.1%, 25.8% and 23.4% in the three groups, respectively. Dinggui Oil Capsule showed a higher efficacy than the placebo in relieving the abdominal pain (P<0.01). No adverse effects were found in this trial. CONCLUSION: Dinggui Oil Capsule is effective and safe in relieving abdominal pain due to IBS with stagnation of qi and cold.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Medicina Tradicional Chinesa , Fitoterapia , Adolescente , Adulto , Idoso , Cápsulas , Diagnóstico Diferencial , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(4): 711-4, 2006 Apr.
Artigo em Zh | MEDLINE | ID: mdl-16836146

RESUMO

The interaction of chitosan (CTS), carboxymethyl chitosans (CMCTS), and carboxymethyl cellulose (CMCL) with DNA was investigated through ethidium bromide (EB) as a sensitive fluorescence probe, and ultraviolet absorption spectra. The constant D can directly denote the degree of interaction of polysaccharide with DNA. The results indicated that the interraction sequence of biological polysaccharides with DNA is as follows: CTS>CMCTS>CMCL. The polysaccharides were mainly bound to DNA by intercalated binding, which resulted in fluorescence quenching effect of EB-DNA.


Assuntos
Quitosana/análogos & derivados , DNA/química , Etídio/análogos & derivados , Quitosana/química , Etídio/química , Corantes Fluorescentes/química , Humanos
20.
Polymers (Basel) ; 8(4)2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30979230

RESUMO

Bacterial cellulose (BC) has great potential to be used as a new filler to reinforce isotactic polypropylene (iPP) due to its high crystallinity, biodegradability, and efficient mechanical properties. In this study, esterification was used to modify BC, which improved the surface compatibility of the iPP and BC. The results indicated that the cellulose octoate (CO) changed the surface properties from hydrophilic to lipophilic. Compared to the pure iPP, the tensile strength, charpy notched impact strength, and tensile modulus of the iPP/BC composites increased by 9.9%, 7.77%, and 15.64%, respectively. However, the addition of CO reinforced the iPP/CO composites. The tensile strength, charpy notched impact strength, and tensile modulus of the iPP/CO composites increased by 14.23%, 14.08%, and 17.82% compared to the pure iPP. However, the elongation at break of both the composites is decreased. The SEM photographs and particle size distribution of the composites showed improvements when the change of polarity of the BC surface, interface compatibility, and dispersion of iPP improved.

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