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1.
Molecules ; 27(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35684437

RESUMO

Bacterial cellulose (BC) is well known as a high-performance dietary fiber. This study investigates the adsorption capacity of BC for cholesterol, sodium cholate, unsaturated oil, and heavy metal ions in vitro. Further, a hyperlipidemia mouse model was constructed to investigate the effects of BC on lipid metabolism, antioxidant levels, and intestinal microflora. The results showed that the maximum adsorption capacities of BC for cholesterol, sodium cholate, Pb2+ and Cr6+ were 11.910, 16.149, 238.337, 1.525 and 1.809 mg/g, respectively. Additionally, BC reduced the blood lipid levels, regulated the peroxide levels, and ameliorated the liver injury in hyperlipidemia mice. Analysis of the intestinal flora revealed that BC improved the bacterial community of intestinal microflora in hyperlipidemia mice. It was found that the abundance of Bacteroidetes was increased, while the abundance of Firmicutes and Proteobacteria was decreased at the phylum level. In addition, increased abundance of Lactobacillus and decreased abundance of Lachnospiraceae and Prevotellaceae were obtained at the genus level. These changes were supposed to be beneficial to the activities of intestinal microflora. To conclude, the findings prove the role of BC in improving lipid metabolism in hyperlipidemia mice and provide a theoretical basis for the utilization of BC in functional food.


Assuntos
Hiperlipidemias , Metabolismo dos Lipídeos , Animais , Bactérias , Bacteroidetes , Celulose/farmacologia , Colesterol , Hiperlipidemias/tratamento farmacológico , Camundongos , Colato de Sódio
2.
Prep Biochem Biotechnol ; 50(4): 330-340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31747333

RESUMO

Apple pomace was explored as alternative feedstock for producing bacterial cellulose (BC) by Gluconacetobacter xylinus following a cellulase saccharification performed after pretreatment of 1-allyl-3-methylimidazolium chloride ([AMIM]Cl). The dissolving process of apple pomace cellulose was observed by polarized light microscopy (PLM). As FT-IR and XRD results demonstrated, the IL pretreatment proved to be a physical process and no changes in the crystalline structure occurred during the pretreatment. However, the SEM result showed that more fissures and breakages appeared on the surface of pomace microfibers after IL-pretreating, which increased the contact area with cellulase and improved the enzymatic hydrolysis efficiency. An enhancing effect on the BC yield has been observed, 27% higher yield of BC obtained from hydrolysate as compared to sucrose-based medium indicates efficiency of IL-treated apple pomace to serve as high quality feedstock in BC production.


Assuntos
Celulose/biossíntese , Gluconacetobacter xylinus/metabolismo , Líquidos Iônicos/química , Celulase/química , Frutas/química , Frutas/metabolismo , Hidrólise , Malus/química , Malus/metabolismo
3.
Langmuir ; 35(5): 1895-1901, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30145900

RESUMO

Zwitterionic polymers are continually suggested as promising alternatives to tune the surface/interface properties of materials in many fields because of their unique molecular structures. Tremendous efforts have been devoted to immobilizing zwitterionic polymers (polyzwitterions, PZIs) on the material surfaces. However, these efforts usually suffer from cumbersome and time-consuming procedures. Herein we report a one-step strategy to facilely achieve the bioinspired polydopamine/polyzwitterion (PDA/PZI) coatings on various substrates. It requires only 30 min to form PDA/PZI coatings by mixing oxidant, dopamine, and zwitterionic monomers, including carboxybetaine methacrylate (CBMA), sulfobetaine methacrylate (SBMA), and 2-methacryloxyethyl phosphorylcholine (MPC). These bioinspired coatings display multifunctional properties such as underwater antioil-adhesion and antifreezing thanks to their high hydrophilicity and underwater superoleophobicity. The coatings even show the antiadhesion property for crude oil with high viscosity. Therefore, the PDA/PZI-coated meshes are efficient for separating both light oil and crude oil from oil/water mixtures. All these results demonstrate that the one-step strategy is a facile approach to design and exploit the bioinspired PDA/PZI coatings for diverse applications.


Assuntos
Betaína/química , Indóis/química , Metacrilatos/química , Petróleo , Fosforilcolina/análogos & derivados , Polímeros/química , Ácidos Polimetacrílicos/química , Betaína/síntese química , Congelamento , Indóis/síntese química , Metacrilatos/síntese química , Fosforilcolina/síntese química , Fosforilcolina/química , Polímeros/síntese química , Ácidos Polimetacrílicos/síntese química , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Propriedades de Superfície , Água/química
4.
Biodivers Data J ; 8: e59726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33250637

RESUMO

BACKGROUND: Polychaetes of the family Capitellidae are poorly studied in Chinese waters. Amongst the known capitellid genera in China, Leiochrides Augener, 1914 is an unusual genus encountered in marine surveys. NEW INFORMATION: In this study, a Leiochrides specimen was obtained during a survey conducted in the Beibu Gulf, northern South China Sea and described herein as a new species Leiochrides guangxiensis sp. nov. The new species differs from its congeners by having uniramous chaetiger 1, chaetigers 11-12 with notopodial capillaries and neuropodial hooks, abdominal hooks with seven teeth above the main fang in three rows, pygidium with four anal cirri, and branchial fascicles with up to 17 filaments. The taxonomic status of the monospecific genus Pseudoleiocapitella Harmelin, 1964 and Leiochrides norvegicus Fauchald, 1972 are discussed.

5.
Int J Biol Macromol ; 140: 196-205, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31430489

RESUMO

A porous microsphere with good biocompatibility was fabricated based on collagen (COL) and bacterial cellulose (BC). The adsorption and release behaviors of the COL/BC porous microspheres were studied using BSA as the model protein, and employing quasi-primary, quasi-secondary, and Kannan-Sundaram intragranular diffusion models, zero-order, first-order, Higuchi and Korsmeyer-Peppas models. The results showed that the COL/BC porous microspheres are beneficial to the proliferation of MC3T3 E1-cells. The linear Langmuir equation can accurately describe the adsorption equilibrium relationship of BSA to the COL/BC microspheres. The pseudo-second-order model can more accurately explain and predict the membrane diffusion kinetics of BSA than both pseudo-primary-order and Kannan-Sundaram intragranular diffusion models. The adsorption rate was affected by both membrane and intragranular diffusions. The drug release behavior indicated that the microsphere-loaded BSA was primarily adsorbed at the inner wall of the pore, and exhibited the characteristics of a scaffold-based matrix meanwhile. The drug release kinetics can be accurately described by the first-order release model. The present study elucidated the mechanism of drug adsorption and release of COL/BC porous microspheres and provided a theoretical basis for its application in controlled release technology.


Assuntos
Celulose/química , Colágeno/química , Liberação Controlada de Fármacos , Soroalbumina Bovina/química , Adsorção , Animais , Linhagem Celular , Proliferação de Células , Celulose/ultraestrutura , Colágeno/ultraestrutura , Difusão , Cinética , Camundongos , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Porosidade
6.
Menopause ; 23(4): 451-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26757270

RESUMO

OBJECTIVE: The aim of the study was to compare the effectiveness and safety of solifenacin succinate tablets alone or combined with local estrogen for overactive bladder treatment in postmenopausal women. METHODS: This multicenter, randomized, open, parallel-controlled clinical trial enrolled 104 women between January 2012 and August 2013. Participants meeting the inclusion criteria were randomized 1:1 to 12 weeks of treatment with group A (solifenacin 5 mg qd + promestriene vaginal capsules intravaginally) or group B (solifenacin 5 mg qd). Before and after 12 weeks of treatment, symptoms (urinary urgency, frequency, and urge incontinence) were analyzed. Our primary outcome was the change from baseline to the end of treatment in the mean number of voids in 24 hours. Quality of life (QoL) was assessed using International Prostate Symptom Score and Overactive Bladder Symptom Score questionnaires and safety according to the incidence of adverse events. The t test or the Mann-Whitney U test was used to compare continuous variables, and the χ(2) test or Fisher's exact test was used to compare categorical variables. RESULTS: The median decreases in the mean number of voids in 24 hours in groups A and B were 5.2. and 4.3, respectively, which were not significantly different. The median decreases in urgency episodes in groups A and B were 2.0 and 2.5, respectively. In addition, the QoL scores significantly changed in both groups (both P < 0.05). The most common adverse event was dry mouth (19.2% in both groups). CONCLUSIONS: Solifenacin with or without local estrogen was effective and safe for overactive bladder treatment in postmenopausal women. The addition of local estrogen improved subjective feelings and QoL.


Assuntos
Estrogênios/administração & dosagem , Pós-Menopausa , Succinato de Solifenacina/uso terapêutico , Bexiga Urinária Hiperativa/tratamento farmacológico , Agentes Urológicos , Administração Intravaginal , Idoso , China , Estrogênios/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Antagonistas Muscarínicos/uso terapêutico , Qualidade de Vida , Succinato de Solifenacina/efeitos adversos , Inquéritos e Questionários , Resultado do Tratamento
7.
Tissue Cell ; 37(5): 349-57, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16002113

RESUMO

The purposes of this study were to develop a new cultural method for the rat bone marrow stromal cells (MSCs) to differentiate into osteoblasts well in vitro, and to investigate the feasibility of using MSCs as seed cells and three-dimensional porous nano-hydroxylapatite as scaffolds for constructing tissue-engineered bone. MSCs of rats were isolated, cultured, induced to differentiate into osteoblasts, and then observed with inverted microscopy. Histochemical staining and radio-immunological analysis were applied for identifying MSCs. Whereafter MSCs were seeded onto three-dimensional porous nano-hydroxylapatite scaffolds, and scanning electron microscopy was applied to evaluate their growth on scaffolds. Results showed that MSCs were typical fibroblast-like and possessed a better proliferating capability; the activity of alkaline phosphatase (ALP) and the secretion of osteocalcin of MSCs were produced gradually and increased continuously; the cells seeded on three-dimensional porous nano-hydroxylapatite scaffolds adhered, proliferated and differentiated well. These results demonstrated that the new improved culture method had the advantages of short isolating time, less risk of contamination and higher efficiency and accordingly was conducive to MSCs proliferating and differentiating into osteoblasts, and that it was advantageous to constructing tissue-engineered bone using MSCs as seed cells and three-dimensional porous nano-hydroxylapatite as scaffolds.


Assuntos
Células da Medula Óssea/citologia , Técnicas de Cultura de Células/métodos , Osteoblastos/citologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis , Diferenciação Celular , Durapatita , Estudos de Viabilidade , Microscopia Eletrônica de Varredura , Microesferas , Nanotecnologia , Ratos , Ratos Sprague-Dawley , Células Estromais/citologia
8.
World J Gastroenterol ; 9(2): 262-6, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12532444

RESUMO

AIM: To obtain an efficient delivery system for transporting endostatin gene to mouse liver tumor xenografts by administration of aerosol. METHODS: Recombinant plasmid pcDNA3.0/endostatin containing human endostatin gene together with signal peptide from alkaline phosphatase were transferred into human umbilical vein endothelial cell (HUVEC) by transferrin(TF)-liposome-endostatin complex. Western blot was used to detect the expression of human endostatin in transfected HUVEC cells and its medium. After the tumor-bearing mice were administrated with TF-liposome-endostatin complex, the lung tissue was analyzed by immunohistochemical method for expression of endostatin and the tumors were treated with CD-31 antibody to detect the density of microvessels in tumor tissues. The inhibition of tumor growth was estimated by the weight of tumors from groups treated with different doses of TF-liposome-endostatin complex. DNA fragmentation assay was used to detect the apoptosis of the cells from primary liver tumor. RESULTS: Western blot analysis and immunohistochemical method confirmed the expression of endostatin protein in vitro and in vivo. After the tumor sections were treated with CD-31 antibody, the positive reaction cells appeared brown while the negative cells were colorless. The positively stained area of the TF-liposome-endostatin treated group was significantly smaller (P<0.01, 645.8+/-55.2 microm(2)) than that of the control group (1 325.4+/-198.5 microm(2)). The data showed a significant inhibition of angiogenesis. After administration of TF-liposome-endostatin, comparing with the control group administrated with TF-liposome-pcDNA3.0, liver tumor growth in the mice treated with 50, 250 and 500 mg DNA/kg was inhibited by 36.6 %, 40.8 %, and 72.8 %, respectively (P<0.01). And a typical DNA fragmentation of apoptosis was found in the cells from tumor tissues of the mice treated with TF-liposome-endostatin but none in the control group. CONCLUSION: Endostatin gene could be efficiently transported into the mice with TF-liposome-DNA delivery system by administration of aerosol. TF-liposome-mediated endostatin gene therapy strongly inhibited angiogenesis and the growth of mouse xenograft liver tumors. It also could promote the development of apoptosis of tumors without direct influence on tumor cells.


Assuntos
Colágeno/genética , Terapia Genética/métodos , Neoplasias Hepáticas Experimentais/irrigação sanguínea , Neoplasias Hepáticas Experimentais/patologia , Neovascularização Patológica/prevenção & controle , Fragmentos de Peptídeos/genética , Aerossóis , Animais , Endostatinas , Feminino , Humanos , Lipossomos/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transferrina/administração & dosagem
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(2): 220-3, 2009 Feb.
Artigo em Zh | MEDLINE | ID: mdl-19246283

RESUMO

OBJECTIVE: To evaluate nacre powder-induced osteogensis in the femoral condyles of New Zealand rabbits and investigate the possible mechanism. METHODS: Nacre powder was implanted into the femoral condyles of New Zealand rabbits and 4, 8, and 12 weeks after the implantation, radiographic examinations were carried out and the bone density was evaluated. The bone tissue specimens were sliced after fixation for histological observations. The osteogenesis area on the slice was estimated with Ponceau Red staining 8 and 12 weeks after the implantation and calculated with Imaga-Pro software. RESULTS: X-ray after the operation did not reveal obvious evidence of angiogenesis in the femoral condyles, where the X-ray density underwent slight changes. The optical density decreased significantly after the implantation, and the quantity of the osteoid, woven and lamellar bone increased in the bone tissue with time. The osteogenesis area with Ponceau Red staining showed obvious bone formation, which was significantly different from the control group. CONCLUSION: T Obvious osteogenesis occurred in the femoral condyles after nacre powder implantation in New Zealand rabbits. Nacre powder has slow biodegradation in vivo and induces osteogenesis by osteoinduction.


Assuntos
Substitutos Ósseos , Carbonato de Cálcio , Cálcio , Fêmur/fisiopatologia , Implantes Experimentais , Osteogênese , Óxidos , Animais , Materiais Biocompatíveis , Feminino , Fêmur/cirurgia , Masculino , Coelhos , Distribuição Aleatória , Engenharia Tecidual/métodos
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(12): 2171-3, 2008 Dec.
Artigo em Zh | MEDLINE | ID: mdl-19114348

RESUMO

OBJECTIVE: To assess the improvements in the properties of nano-nacre artificial bone prepared on the basis of nacre/polylactide acid composite artificial bone and its potential for clinical use. METHODS: The compound of nano-scale nacre powder and poly-D, L-lactide acid (PDLLA) was used to prepare the cylindrical hollow artificial bone, whose properties including raw material powder scale, pore size, porosity and biomechanical characteristics were compared with another artificial bone made of micron-scale nacre powder and PDLLA. RESULTS: Scanning electron microscope showed that the average particle size of the nano-nacre powder was 50.4-/+12.4 nm, and the average pore size of the artificial bone prepared using nano-nacre powder was 215.7-/+77.5 microm, as compared with the particle size of the micron-scale nacre powder of 5.0-/+3.0 microm and the pore size of the resultant artificial bone of 205.1-/+72.0 microm. The porosities of nano-nacre artificial bone and the micron-nacre artificial bone were (65.4-/+2.9)% and (53.4-/+2.2)%, respectively, and the two artificial bones had comparable compressive strength and Young's modulus, but the flexural strength of the nano-nacre artificial bone was lower than that of the micro-nacre artificial bone. CONCLUSIONS: The nano-nacre artificial bone allows better biodegradability and possesses appropriate pore size, porosity and biomechanical properties for use as a promising material in bone tissue engineering.


Assuntos
Substitutos Ósseos/química , Carbonato de Cálcio/química , Ácido Láctico/química , Teste de Materiais , Nanopartículas/química , Polímeros/química , Implantes Absorvíveis , Animais , Materiais Biocompatíveis/química , Bivalves/química , Composição de Medicamentos/métodos , Humanos , Poliésteres , Porosidade , Resistência à Tração
11.
Vaccine ; 26(6): 769-77, 2008 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-18191307

RESUMO

To optimize previous candidate DNA vaccine, a cis-expression plasmid DNA encoding two genes, human IL-2 and multiple-epitopes genes of foot-and-mouth disease virus (FMDV) was constructed with internal ribosome entry site (IRES) from encephalomyocarditis virus (EMCV) and intramuscularly inoculated into mice at 1-week interval. Specific antibodies in serum and cytokines (IL-2, IL-4 and IFN-gamma) from splenocytes were detected by indirect ELISA. Splenocytes proliferation rate was determined by a standard 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT) method. The results showed that higher specific antibody, proliferate rate and cytokines were induced by plasmid DNA cis-expression with IL-2 compared to non-cis-expression plasmid DNA. Another series of mice were inoculated with plasmid DNA and boosted with antigenic protein. Specific antibody, proliferation rate and cytokines were induced significantly higher than those of mice immunized with protein or plasmid DNA only. However, only the cis-expression plasmid DNA elicited higher neutralization antibody in mice and provided one third protection against homologous virus in guinea pigs. In conclusion, cis-expression strategy with IL-2 up-regulated specific immunological response and provide protection against homologous virus.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Plasmídeos/metabolismo , Vacinação , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Citocinas/análise , Citocinas/biossíntese , Vírus da Encefalomiocardite/metabolismo , Ensaio de Imunoadsorção Enzimática , Epitopos/biossíntese , Epitopos/genética , Feminino , Febre Aftosa/sangue , Expressão Gênica , Cobaias , Humanos , Esquemas de Imunização , Injeções Intramusculares , Interleucina-2/biossíntese , Interleucina-2/genética , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Subunidades Ribossômicas/metabolismo , Baço/imunologia , Baço/metabolismo , Vacinas de DNA/administração & dosagem , Vacinas de DNA/imunologia , Vacinas Virais/administração & dosagem
12.
Vaccine ; 23(48-49): 5632-40, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16125283

RESUMO

It is known that only the minority of plasmid DNAs effect a cure or prevention after intramuscular injection into host. But what is the fate of the majority? And indeed how many of the injected DNAs work? Till now, little is known about it. To answer these questions, two methods including PCR and autoradiography were used in distribution study in mice that had received a single muscular inoculation of plasmid DNA containing antigenic epitopes of foot-and-mouth disease virus. The results showed that the plasmid DNAs were distributed by blood circulation and degraded soon. The degradation ratio of super coiled plasmid DNA was 20.9% in 10 min, 34.1% in 1h, 86.8% in 1 day and 97.8% in 1 week in sera in vivo. And over a half of the whole were output in urine and faeces. The rest resided most in muscles as 'antigen pool', next in immune organs, kidney, liver, heart, lung and little in brain or gonad. About 40% or 0.5% of total plasmid DNAs, inferring to be effective, resided in muscles or immune organs, respectively. Collective results suggested that 'nude' DNA, as water injection, was characterized as quick absorbent, extensive distribution, but low utilization rate. Finally, the immune mechanism for the DNA vaccine was discussed.


Assuntos
Epitopos/química , Vírus da Febre Aftosa/genética , Plasmídeos/metabolismo , Distribuição Tecidual , Vacinas de DNA/metabolismo , Vacinas Virais/metabolismo , Animais , Epitopos/imunologia , Injeções Intramusculares , Camundongos , Plasmídeos/efeitos adversos , Plasmídeos/genética , Vacinas Virais/genética
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