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1.
Mar Drugs ; 21(9)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37755081

RESUMO

Ascophyllum nodosum, a brown algae abundantly found along the North Atlantic coast, is recognized for its high polysaccharide content. In this study, we investigated the anti-hyperlipidemic effect of fucoidans derived from A. nodosum, aiming to provide information for their potential application in anti-hyperlipidemic therapies and to explore comprehensive utilization of this Iceland brown seaweed. The crude fucoidan prepared from A. nodosum was separated using a diethylethanolamine column, resulting in two fucoidan fractions, AFC-1 and AFC-2. Both fractions were predominantly composed of fucose and xylose. AFC-1 exhibited a higher sulfate content of 27.8% compared to AFC-2 with 17.0%. AFC-2 was primarily sulfated at the hydroxy group of C2, whereas AFC-1 was sulfated at both the hydroxy groups of C2 and C4. To evaluate the anti-hyperlipidemic effect, a hyperlipidemia mouse model was established by feeding mice a high-fat diet. The effects of AFC-1, AFC-2, and the crude extract were investigated, with the drug atorvastatin used as a positive comparison. Among the different fucoidan fractions and doses, the high dose of AFC-2 administration demonstrated the most significant anti-hyperlipidemic effect across various aspects, including physiological parameters, blood glucose levels, lipid profile, histological analysis, and the activities of oxidative stress-related enzymes and lipoprotein-metabolism-related enzymes (p < 0.05 for the final body weight and p < 0.01 for the rest indicators, compared with the model group), and its effect is comparable to the atorvastatin administration. Furthermore, fucoidan administration resulted in a lower degree of loss in gut flora diversity compared to atorvastatin administration. These findings highlight the significant biomedical potential of fucoidans derived from A. nodosum as a promising therapeutic solution for hypolipidemia.

2.
Food Funct ; 14(12): 5690-5701, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37272879

RESUMO

This study investigated the protective properties of fecal microbiota derived from mice treated with sodium alginate (SA) and normal mice with both types immunosuppressed by exposure to antibiotics and cyclophosphamide. A dietary intervention using SA obviously increased the diversity and improved the composition of gut microbiota in normal mice. Fecal microbiota transfer (FMT) from both mice treated with sodium alginate and normal mice alleviated spleen tissue damage and improved immune function. FMT alleviated intestinal mucosal injury and reduced intestinal permeability via increasing mucin and tight junction protein expression. In addition, FMT reduced gut inflammation via down-regulating the expression of toll-like receptor 4 protein. Furthermore, FMT treatment improved the disordered gut microbiota via increasing the abundance of Lactobacillus and Lachnospiraceae NK4A136 group whilst decreasing the abundance of Bacteroides. PICRUSt2 function prediction analysis showed that, compared with the model group, FMT treatment significantly down-regulated lipopolysaccharide biosynthesis and the mitogen-activated protein kinase signaling pathway-fly. Collectively, we found that SA can regulate the gut microbiota structure of normal mice and confirms the effectiveness of FMT in alleviating intestinal barrier damage and gut dysbiosis in antibiotic-cyclophosphamide-induced immunosuppressed mice. This work also reveals that SA can potentially alleviate the immunosuppression caused by cyclophosphamide in mice by modulating the intestinal microbiota and exploiting their functional properties.


Assuntos
Transplante de Microbiota Fecal , Enteropatias , Animais , Camundongos , Disbiose/induzido quimicamente , Disbiose/terapia , Disbiose/metabolismo , Mucosa Intestinal/metabolismo , Enteropatias/metabolismo , Inflamação/metabolismo , Receptores Toll-Like/metabolismo
3.
Nutr. hosp ; 40(2): 241-249, mar.-abr. 2023. tab
Artigo em Inglês | IBECS | ID: ibc-219318

RESUMO

Background and objectives: to investigate the association between the dietary nutrient intake and nutritional status of patients with Crohn’s disease (CD). Methods: sixty CD patients who had been diagnosed but had not begun treatment were enrolled. The dietary nutrient intake was recorded after three days of 24-hour recall and was calculated using NCCW2006 software. The nutrition levels were assessed using the Patient-Generated Subjective Global Assessment (PG-SGA). Indicators included body mass index (BMI), mid-arm circumference, the circumference of the upper-arm muscle, triceps skinfold thickness, handgrip strength, and the circumference of both calves. Results: eighty-five per cent of CD patients did not meet the necessary energy requirements. Of these, the protein and dietary fiber intake in 63.33 % and 100 %, respectively, were below the standard of the Chinese dietary reference. Many patients had insufficient intake of vitamins, as well as other macro- and micronutrients. An inverse association was observed between the risk of malnutrition and higher levels of energy (1,590.0-2,070.6 kcal/d, OR = 0.050, 95 % CI: 0.009-0.279) and protein (55.6-70.5 g/d, OR = 0.150, 95 % CI: 0.029-0.773). Appropriate supplementation of vitamin E, calcium, and other dietary nutrients helped to reduce the risk of malnutrition. (AU)


Antecedentes y objetivos: investigar la asociación entre la ingesta de nutrientes y el estado nutricional de los pacientes con enfermedad de Crohn (EC). Métodos: se reclutaron 60 pacientes de EC que habían sido diagnosticados, pero no habían iniciado ningún tratamiento. La ingesta de nutrientes se registró tras 3 días de recordatorio de 24 horas y se calculó utilizando el software NCCW2006. El estado nutricional se evaluó mediante la valoración global subjetiva generada por el paciente (PG-SGA). Los indicadores incluyeron el índice de masa corporal, la circunferencia media del brazo, la circunferencia del músculo de la parte superior del brazo, el grosor del pliegue cutáneo del tríceps, la fuerza de agarre y la circunferencia de la pantorrilla. Resultados: el 85 % de los pacientes de EC no cubrieron las necesidades energéticas necesarias. De estos, las ingestas de proteína y fibra dietética en el 63,33 % y el 100 %, respectivamente, era más baja que lo que recominenda la norma de referencia dietética china. Muchos pacientes tuvieron una ingesta insuficiente de vitaminas, así como de otros macronutrientes y micronutrientes. Se observó una asociación inversa entre el riesgo de desnutrición y niveles más altos de energía (1590,0-2070,6 kcal/d, OR = 0,050, IC 95 % = 0,009-0,279) y proteínas (55,6-70,5 g/d, OR = 0,150, IC 95 % = 0,029-0,773). La suplementación adecuada de vitamina E, calcio y otros nutrientes dietéticos ayudó a reducir el riesgo de desnutrición. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Doença de Crohn , Ingestão de Alimentos , Desnutrição/complicações , China , Nutrientes , Estudos Transversais , Estado Nutricional
4.
Nutr Hosp ; 40(2): 241-249, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36880732

RESUMO

Introduction: Background and objectives: to investigate the association between the dietary nutrient intake and nutritional status of patients with Crohn's disease (CD). Methods: sixty CD patients who had been diagnosed but had not begun treatment were enrolled. The dietary nutrient intake was recorded after three days of 24-hour recall and was calculated using NCCW2006 software. The nutrition levels were assessed using the Patient-Generated Subjective Global Assessment (PG-SGA). Indicators included body mass index (BMI), mid-arm circumference, the circumference of the upper-arm muscle, triceps skinfold thickness, handgrip strength, and the circumference of both calves. Results: eighty-five per cent of CD patients did not meet the necessary energy requirements. Of these, the protein and dietary fiber intake in 63.33 % and 100 %, respectively, were below the standard of the Chinese dietary reference. Many patients had insufficient intake of vitamins, as well as other macro- and micronutrients. An inverse association was observed between the risk of malnutrition and higher levels of energy (1,590.0-2,070.6 kcal/d, OR = 0.050, 95 % CI: 0.009-0.279) and protein (55.6-70.5 g/d, OR = 0.150, 95 % CI: 0.029-0.773). Appropriate supplementation of vitamin E, calcium, and other dietary nutrients helped to reduce the risk of malnutrition. Conclusions: significant deficiencies in dietary nutrient intake were found in CD patients, and dietary intake was associated with the nutritional status of the patient. Appropriate adjustment and supplementation of nutrient intake may reduce malnutrition risk in CD patients. The gap between actual consumption and recommendation indicates a need for improved nutritional counseling and monitoring. Early relevant advice for the dietary guidance of CD patients may be beneficial for long-term effects associated with nutritional status.


Introducción: Antecedentes y objetivos: investigar la asociación entre la ingesta de nutrientes y el estado nutricional de los pacientes con enfermedad de Crohn (EC). Métodos: se reclutaron 60 pacientes de EC que habían sido diagnosticados, pero no habían iniciado ningún tratamiento. La ingesta de nutrientes se registró tras 3 días de recordatorio de 24 horas y se calculó utilizando el software NCCW2006. El estado nutricional se evaluó mediante la valoración global subjetiva generada por el paciente (PG-SGA). Los indicadores incluyeron el índice de masa corporal, la circunferencia media del brazo, la circunferencia del músculo de la parte superior del brazo, el grosor del pliegue cutáneo del tríceps, la fuerza de agarre y la circunferencia de pantorrilla. Resultados: el 85 % de los pacientes de EC no cubrieron las necesidades energéticas necesarias. De estos, las ingestas de proteína y fibra dietética en el 63,33 % y el 100 %, respectivamente, era más baja que lo que recominenda la norma de referencia dietética china. Muchos pacientes tuvieron una ingesta insuficiente de vitaminas, así como de otros macronutrientes y micronutrientes. Se observó una asociación inversa entre el riesgo de desnutrición y niveles más altos de energía (1590,0-2070,6 kcal/d, OR = 0,050, IC 95 % = 0,009-0,279) y proteínas (55,6-70,5 g/d, OR = 0,150, IC 95 % = 0,029-0,773). La suplementación adecuada de vitamina E, calcio y otros nutrientes dietéticos ayudó a reducir el riesgo de desnutrición. Conclusiones: se observaron deficiencias significativas en la ingesta de nutrientes en los pacientes con EC, y la ingesta dietética se asoció con el estado nutricional del paciente. El ajuste y la suplementación adecuados de la ingesta de nutrientes pueden reducir el riesgo de malnutrición de los pacientes con EC. La diferencia entre el consumo real y la recomendación indica la necesidad de mejorar el asesoramiento y el seguimiento nutricional. El consejo temprano pertinente para la orientación dietética de los pacientes con EC puede ser beneficioso para los efectos a largo plazo asociados al estado nutricional.


Assuntos
Doença de Crohn , Desnutrição , Humanos , Estado Nutricional , Força da Mão , Ingestão de Energia , Ingestão de Alimentos , Vitaminas , Desnutrição/complicações
5.
Polymers (Basel) ; 14(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893976

RESUMO

A novel fluorescein-based probe FLA-Boe was developed for detecting H2O2. Modified by 2-Bromomethylphenylboronic acid pinacol ester, FLA-Boe is a Fluorescein derivative with eminent photostability and remarkable H2O2 sensitivity and selectivity. FLA-Boe was utilized to synthesize hydrogel sensors in the manner of guest-host interaction by taking advantage of its aforementioned features. The hydrogel sensor can be used to detect H2O2 effectively in both flowing and static water environments with satisfactory performance. It is expected that this application may open a new page to develop a neoteric fluorescent property analysis method aiming at H2O2 detection.

6.
Int J Biol Macromol ; 183: 1978-1986, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34087304

RESUMO

Marine polysaccharide-based hydrogels have drawn much attention for diversified biomedical applications owing to their excellent (bio)physicochemical properties. In the present work, a series of marine polysaccharide-based hydrogels composed of chitosan, alginate, or fucoidan are prepared via a facile chemical cross-linking approach in an alkali/urea aqueous system. The prepared hydrogels possess tunable microporous architecture, swelling, and biodegradable properties by changing the components and proportions of marine polysaccharides. Importantly, the developed hydrogels are mechanically robust and the maximum compressive stress is up to 28.37 ± 4.63 kPa. Furthermore, the composite hydrogels exhibit excellent cytocompatibility, blood compatibility, and histocompatibility. When implanted subcutaneously in rats, the hydrogels containing fucoidan inhibit the inflammatory response of surrounding tissue. Thus, the designed composite hydrogels are promising bio-scaffolds in biomedical applications.


Assuntos
Anti-Inflamatórios/administração & dosagem , Organismos Aquáticos/química , Materiais Biocompatíveis/administração & dosagem , Hidrogéis/administração & dosagem , Polissacarídeos/química , Alginatos/química , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacologia , Masculino , Camundongos , Ratos , Alicerces Teciduais
7.
Int J Biol Macromol ; 167: 182-192, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33259842

RESUMO

Conventional wound-dressing materials with structural and functional deficiencies are not effective in promoting wound healing. The development of multifunctional wound dressings is emerging as a promising strategy to accelerate blood coagulation, inhibit bacterial infection, and trigger full-thickness wound into a regenerative process. Herein, multifunctional composite sponges were developed by incorporation of traditional Chinese medicine Kangfuxin (KFX) into alginate (AG)/carboxymethyl chitosan (CMC) via green crosslinking, electrostatic interaction, and freeze-drying methods. It is demonstrated that the AG/CMC/KFX (ACK) sponges exhibit a highly interconnected and porous structure, suitable water vapor transmittance, excellent elastic properties, antibacterial behavior, cytocompatibility, and rapid hemostasis. Further, in a rat full-thickness wounds model, the ACK sponge containing 10% KFX (ACK-10) significantly facilitates wound closure compared to the AC group and ACK sponge containing 5% and 15% KFX. Thus, the multifunctional ACK-10 composite sponge has great promise for the application of full-thickness wound healing.


Assuntos
Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Quitosana/análogos & derivados , Materia Medica/química , Cicatrização/efeitos dos fármacos , Organismos Aquáticos/química , Bandagens , Biodegradação Ambiental , Adesão Celular/efeitos dos fármacos , Fenômenos Químicos , Quitosana/química , Humanos , Fenômenos Mecânicos , Testes de Sensibilidade Microbiana , Reologia , Análise Espectral
8.
Ann N Y Acad Sci ; 1462(1): 65-78, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31495936

RESUMO

Oral squamous cell carcinoma (OSCC) is one of the most common cancer types, with a high annual incidence. Although chemotherapy contributes to suppressing OSCC tumorigenesis, the available treatments result in poor prognosis because of local recurrence and regional lymph node metastasis. Thus, it is necessary to discover novel and safe drugs with greater effectiveness and fewer side effects. Fucoidan is a component of the cell wall of brown seaweed that has been shown to produce a wide range of biological activities. The present study aimed to investigate the effectiveness of fucoidan in treating OSCC. In in vitro studies, we found that fucoidan inhibited OSCC growth and suppressed migration and invasion of OSCC cells. In addition, the potential interaction between fucoidan and filamin A (FLNA)-derived circular RNA (circFLNA) was predicted using bioinformatics databases and then confirmed in OSCC samples and cell lines. Indeed, fucoidan increased the expression of circFLNA in OSCC cell lines. Furthermore, both fucoidan and circFLNA could mediate the expression of key proteins related to cell growth, apoptosis, migration, and invasion. In conclusion, our research demonstrated that fucoidan might be considered as a potential natural drug in the treatment of OSCC patients by targeting circFLNA.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/metabolismo , Filaminas/biossíntese , Neoplasias Bucais/metabolismo , Polissacarídeos/farmacologia , RNA Circular/biossíntese , Adulto , Idoso , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Feminino , Filaminas/agonistas , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/tratamento farmacológico , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Polissacarídeos/isolamento & purificação , Polissacarídeos/uso terapêutico , RNA Circular/agonistas , Adulto Jovem
9.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(8): 1041-1044, 2019 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-31407566

RESUMO

OBJECTIVE: To analyze standards of alginate-based medical devices at home and abroad, and to emphasize key issues of quality control that should be concerned about. METHODS: Based on investigation of alginate application in medical devices and alginate-related medical standards, alginate-related technical indicators and quality control points were comprehensively analyzed. RESULTS: With the rapid development of alginate-based medical materials and medical devices, the relevant standards at home and abroad have been elaborated on the basic technical indicators and detection methods. In addition to Chinese Pharmacopoeia, China has issued one alginate standard for tissue engineering and three alginate related product standards. CONCLUSION: Considering the special physical and chemical properties of alginate, researchers also need to focus on the sterilization method, expiry date, molecular weight, and ratio of α-L-guluronic acid to ß-D-mannuronic acid of alginate, and impurity content.


Assuntos
Alginatos , Equipamentos e Provisões/normas , Engenharia Tecidual , China , Peso Molecular , Controle de Qualidade
10.
J Microbiol Biotechnol ; 29(5): 731-738, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31030449

RESUMO

Endophytic fungi are an important component of plant microbiota, and have the excellent capacity for producing a broad variety of bioactive metabolites. These bioactive metabolites not only affect the survival of the host plant, but also provide valuable lead compounds for novel drug discovery. In this study, forty-two endophytic filamentous fungi were isolated from Ficus elastica leaves, and further identified as seven individual taxa by ITS-rDNA sequencing. The antimicrobial activity of these endophytic fungi was evaluated against five pathogenic microorganisms. Two strains, Fes1711 (Penicillium funiculosum) and Fes1712 (Trichoderma harzianum), displayed broad-spectrum bioactivities. Our following study emphasizes the isolation, identification and bioactivity testing of chemical metabolites produced by T. harzianum Fes1712. Two new isocoumarin derivatives (1 and 2), together with three known compounds (3-5) were isolated, and their structures were elucidated using NMR and MS. Compounds 1 and 2 exhibited inhibitory activity against Escherichia coli. Our findings reveal that endophytic fungi from the rubber tree F. elastica leaves exhibit unique characteristics and are potential producers of novel natural bioactive products.


Assuntos
Anti-Infecciosos/farmacologia , Bioprospecção/métodos , Endófitos , Ficus/microbiologia , Fungos/metabolismo , Hevea/microbiologia , Folhas de Planta/microbiologia , Anti-Infecciosos/química , DNA Ribossômico/genética , Descoberta de Drogas , Escherichia coli/efeitos dos fármacos , Fermentação , Fungos/genética , Fungos/isolamento & purificação , Isocumarinas/farmacologia , Penicillium/isolamento & purificação , Penicillium/metabolismo , Trichoderma/isolamento & purificação , Trichoderma/metabolismo
11.
Carbohydr Polym ; 153: 652-662, 2016 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-27561537

RESUMO

Indirect cell contact co-culture system is increasingly becoming more attractable owing to their advantages of easy cell separation and desirable outcomes for cell-cell interactions. However, how to precisely control the spatial position of cells within multicellular co-cultures is still experimentally challenging due to the incapability of the conventional methods in vitro. In the present study, a tunable collagen/alginate-chitosan (Col/Alg-Chi) membrane was established, which was capable of controlling intercellular distance between the neighboring cells at a level of micrometer resolution. It was showed that intercellular distance between the hepatocytes and the fibroblasts exerted significant influence on hepatic function in vitro. In particular, maintenance of the functionality of primary hepatocytes requires direct contact between the hepatocytes and their supportive stromal cells, and their effective contact distance is within 30µm. This technical platform would potentially enable investigations of dynamic cell-cell interaction in a multitude of applications including organogenesis, development or even neoplastic transformation.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Comunicação Celular , Fibroblastos/citologia , Hepatócitos/citologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Animais , Adesão Celular , Linhagem Celular , Células Cultivadas , Quitosana , Técnicas de Cocultura , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Masculino , Membranas Artificiais , Microtecnologia , Ratos Sprague-Dawley
12.
J Pharm Sci ; 105(1): 301-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26554743

RESUMO

Small-interfering RNA (siRNA)-mediated gene silencing with the aid of chitosan (CS)-based carriers has shown efficient and reliable outcome in vitro, but the gene silencing efficiency in vivo is still limited. It is of great importance to balance the protection and release of siRNA from nanoparticles (NPs) so as to achieve high efficiency. However, siRNA release profile from CS/siRNA NPs has been rarely concerned. Here, Förster resonance energy transfer technique was adopted for in vitro investigation of siRNA release from CS NPs in lysozyme-contained buffer. The results clearly showed that siRNA molecules experienced a fast and short release phase under lysozyme competition to both CS and siRNA, and then a slow and long release under lysozyme degradation on CS. Moreover, lysozyme competition played more important role than enzymolysis on trigging siRNA release. This preliminary study of siRNA release is the first step to get insight of in vivo siRNA release mechanism from CS/siRNA NPs, which will be helpful to adjust the design of CS/siRNA NPs for balancing the protection and release of siRNA molecules.


Assuntos
Sistemas de Liberação de Medicamentos , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/farmacocinética , Quitosana , Enzimas/química , Transferência Ressonante de Energia de Fluorescência , Inativação Gênica , Muramidase/química , Nanopartículas , Tamanho da Partícula
13.
Bioprocess Biosyst Eng ; 38(7): 1303-12, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25648763

RESUMO

Microencapsulation supplies cells with a three-dimensional microenvironment enhancing the metabolic activity, cell density and recombinant protein expression in a stirred tank bioreactor which is used widely to culture mammalian cells in many biochemical processes. In this paper, we address the growth and Desmodus rotundus salivary plasminogen activator (DSPA) production of recombinant CHO (rCHO) in a stirred tank bioreactor. Cells were cultured using two different methods--in an unmicroencapsulated versus microencapsulated culture--and compared differences between them in terms of cell reproduction and DSPA protein productivity. Compared to the unmicroencapsulated rCHO, microencapsulated cells got higher cell density and prolonged the plateau phase. Microencapsulated rCHO promoted DSPA production, with a maximum rate that was 4.8 times higher than in unmicroencapsulated cells, and the accumulated production of DSPA was 3.3 higher than in unmicroencapsulated cells. Negative relationship was found between specific growth rate and DSPA production capacity of unit cells. These findings will facilitate the methods for higher DSPA production in stirred tank bioreactors.


Assuntos
Reatores Biológicos , Ativadores de Plasminogênio/biossíntese , Composição de Medicamentos , Proteínas Recombinantes/biossíntese
14.
Biotechnol Appl Biochem ; 62(6): 833-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25524589

RESUMO

Stirred tank bioreactors are the most widely used method for the large-scale culture of mammalian cells. However, the scale of stirred tank bioreactors is limited by insufficient oxygen/nutrient mixing and the accumulation of waste products in high cell density cultures. The most effective method to solve these problems is to increase the stirring rate; this usually leads to increased cell proliferation, but can decrease the utilization of nutrients for recombinant protein synthesis. To investigate the effects of stirring rate on the proliferation, metabolism, and recombinant protein yield of microencapsulated recombinant Chinese hamster ovary (rCHO) cells, the cells were cultured under different stirring rates, and cell viability, metabolic activity, and protein yield were measured. Microencapsulation promoted Desmodus rotundus salivary plasminogen activator expression, and higher stirring rates promoted increases in microencapsulated cell density and metabolic activity. However, the maximum yield of recombinant protein was obtained at a moderate stirring rate, whereas protein yield was decreased at the highest tested stirring rate. The stirring rate had a significant impact on the growth and protein expression of microencapsulated rCHO cells, and a specific stirring rate was identified to maximize the yield of recombinant protein.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células/métodos , Proteínas Recombinantes/biossíntese , Animais , Células CHO , Cápsulas , Proliferação de Células , Cricetinae , Cricetulus , Ativadores de Plasminogênio/biossíntese , Ativadores de Plasminogênio/genética , Proteínas Recombinantes/genética , Fatores de Tempo
15.
Talanta ; 108: 59-65, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23601870

RESUMO

Multicolor carbon nanoparticles (CNPs) were prepared, characterized and developed as fluorescent probes for cell imaging. The fluorescent CNPs were prepared with a facile hydrothermal oxidation route by using linear polysaccharide cellulose and cyclic oligosaccharide cyclodextrin as carbon sources. The characterizations by transmission electron microscopy show that the prepared cellulose-CNPs and cyclodextrin-CNPs are spherical, well-dispersed in water with average diameters of 100 nm and 76 nm, respectively. Under the excitation of UV light, the CNPs are strongly luminescent with an excitation-dependent emission behavior and bathochromic emission properties. The fluorometric methods show that the cellulose-CNPs and cyclodextrin-CNPs are strongly fluorescent with fluorescence quantum yield of 7.47% and 4.49%, respectively. The multicolor CNPs have excellent photostability toward photobleaching. Strong near-infrared fluorescence of the carbon nanoparticles was observed with a 632.8 nm excitation wavelength laser. The oxidative metal ions like Hg(II), Cu(II) and Fe(III) show an quench effect on the fluorescence intensity of the CNPs. The multicolor CNPs were successfully used as fluorescent probes for mouse melanoma cells imaging. The results indicate that the multicolor CNPs derived from cellulose and cyclodextrin may have a great potential for the applications in bioimaging.


Assuntos
Carbono/química , Celulose/química , Ciclodextrinas/química , Corantes Fluorescentes/química , Nanopartículas/química , Animais , Linhagem Celular Tumoral , Cor , Diagnóstico por Imagem , Melanoma Experimental/diagnóstico , Metais/química , Camundongos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
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