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1.
Carbohydr Res ; 539: 109120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669825

RESUMO

Xanthoceras sorbifolium Bunge, also known as Tu-Mu-Gua and Wen-Dan-Ge-Zi, has several applications. Clinical data and experimental studies have shown anti-tumor, anti-inflammatory, anti-bacterial, and anti-oxidant properties of Xanthoceras sorbifolium Bunge that inhibits prostate hyperplasia, lowers blood pressure and lipid level, and treats enuresis and urinary incontinence. It also has neuroprotective effects and can treat Alzheimer's disease and Parkinson's syndrome. The research on the chemical composition and pharmacological effects of Xanthoceras sorbifolium Bunge has been increasing. Triterpenoid and triterpenoid saponins are the main constituents in Xanthoceras sorbifolium Bunge and exhibit biological activities. In this review, we summarized the research progress on triterpenoids and their glycosides in Xanthoceras sorbifolia, including the chemical constituents, pharmacological activities, and biogenic pathways of triterpenoid mother nucleus. The results would provide a reference for further research and development of triterpenoids and their glycosides in Xanthoceras sorbifolia.


Assuntos
Saponinas , Triterpenos , Saponinas/química , Saponinas/farmacologia , Saponinas/isolamento & purificação , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Humanos , Sapindaceae/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação
2.
Molecules ; 29(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542949

RESUMO

Orychophragmus violaceus (L.) O. E. Schulz (Brassicaceae) is widely distributed and plentiful in China and has been widely used for its application in ornamental, oil, ecology, foraging, and food. Recent studies have revealed that the main components of Orychophragmus violaceus include flavonoids, alkaloids, phenylpropanoids, phenolic acids, terpenoids, etc., which have pharmacological activities such as antioxidation, antiradiation, antitumor, hepatic protection, antiferroptosis, anti-inflammatory, and antibacterial. In this paper, the nutritional value, chemical compositions, pharmacological activity, and application value of Orychophragmus violaceus are summarized by referring to the relevant domestic and international literature to provide a reference for further research, development, and utilization of Orychophragmus violaceus in the future.


Assuntos
Alcaloides , Brassicaceae , Brassicaceae/química , Alimentos , Fígado , Valor Nutritivo
3.
Nat Prod Bioprospect ; 13(1): 26, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37639046

RESUMO

An undescribed pyrrole acid, 1-(4'-methoxy-4'-oxobutyl)-1 H-pyrrole-2,5-dicarboxylic acid (1) and one known pyrrole acid (2) were isolated from the fruits of Phyllanthus emblica. The structures of these compounds were elucidated via the comprehensive analyses of IR, HRESIMS, 1D and 2D spectroscopic data. A series of biological assays revealed that compounds 1 and 2 could inhibit LPS-induced over-production of nitric oxide (NO), interleukin-6 (IL-6), monocyte chemotactic protein 1 (MCP-1) and tumor necrosis factor-α (TNF-α) by reducing the phosphorylation of extracellular regulated protein kinases (ERK) and c-Jun N-terminal kinases (JNK) in RAW 264.7 cells. Additionally, compounds 1 and 2 were found to reduce lipid deposition and increase the mRNA expression of ATP-binding cassette transporter A1 in oxidized low-density lipoprotein-treated RAW264.7 macrophages.

4.
Sci Rep ; 10(1): 5994, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32265463

RESUMO

Two rare N-ß-D-glucopyranosyl-1H-indole-3-acetic acid conjugates, N-[2-(1-ß-D-glucopyranosyl)-1H-indol-3-yl)acetyl]-L-glutamic acid (1) and N-[2-(1-ß-D-glucopyranosyl)-1H-indol-3-yl)acetyl]-L-aspartic acid (2) were isolated from Ginkgo biloba. The structures were elucidated by analyses of HRMS and NMR spectroscopic data. In addition, a simplified and efficient synthetic route for compounds 1 and 2 is also disclosed to determine the absolute configurations of them. This concise syntheses of compounds 1 and 2 may facilitate studies of the biology of this type alkaloids. Compounds 1 and 2 were also tested for their cytotoxic and anti-inflammatory activities. The biological evaluation showed that compounds 1 and 2 led to the decrease of interleukin (IL)-6, nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 at mRNA level in lipopolysaccharide (LPS)-stimulated murine macrophage RAW264.7 cells.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Ginkgo biloba/química , Glicosídeos/química , Glicosídeos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Glicosídeos/isolamento & purificação , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Lipopolissacarídeos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7
5.
Zhongguo Zhong Yao Za Zhi ; 44(9): 1734-1738, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31342694

RESUMO

The specifications of Chinese herbal medicines naturally form and exist in the circulation and use of Chinese herbal medicines.Buyers and sellers negotiate price by quality. With the increasing demand for public health care,the cultivation,processing methods and circulation of Chinese herbal medicines have changed. Under the mode of pursuing output and short-term benefits,the traditional grade evaluation method has been difficult to apply to the current quality status of the pieces. Bran stir-baked Aurantii Fructus is a genuine medicinal material in Jiangxi province. It is widely used,but the quality level of bran stir-baked Aurantii Fructus on the market is not uniform. Quality constant method was used in this paper for grading the Chinese herbal slices of bran stir-baked Aurantii Fructus. Sixteen batches of different quality samples were collected and tested,and finally,eleven qualified batches of them were chosen as researcher objects. The results showed that the relative quality constant ranged from 2. 52 to 5. 60. The relative quality constant was ≥4. 48 for first grade bran stir-baked Aurantii Fructus,2. 80-4. 48 for the second grade pieces,and <2. 80 for the third grade pieces. The grades evaluation method for bran stir-baked Aurantii Fructus established in this paper included both appearance and index composition. The results were objective,accurate,quantitative,applicable,and the method was simple to operate and easy to popularize. This study showed that the quality constant method could be applied to the grade evaluation of bran stir-baked Aurantii Fructus,providing a reference for the grade evaluation of fruit-type decoction pieces.


Assuntos
Citrus/química , Medicamentos de Ervas Chinesas/normas , Frutas/química , Controle de Qualidade
6.
Zhongguo Zhong Yao Za Zhi ; 44(9): 1744-1749, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31342696

RESUMO

The quality constant evaluation method was applied in the grade evaluation of Scrophulariae Radix pieces. Nineteen batches of Scrophulariae Radix were measured for the appearance index. Harpagide and harpagoside were taken as index components for the content determination. The traditional grading standard and the modern quality control index were combined to calculate the quality constant and grade Scrophulariae Radix pieces. The results showed that the quality constants ranged between 156. 75 and 491. 65; according to the percentage mass constants,more than 80% were graded as first-class pieces,50%-80% were graded as second-class pieces,and the rest were graded as third-class pieces. The quality constants of first-class Scrophulariae Radix were >393. 32,that of second-class Scrophulariae Radix was between 245. 83 and 393. 32,and that of third-class Scrophulariae Radix was < 245. 83. The study shows that this method can objectively,reasonably and effectively classify Scrophulariae Radix pieces,and further promote and apply the evaluation method of slice model quality constant to prove the rationality,scientificity and practicability.


Assuntos
Medicamentos de Ervas Chinesas/normas , Scrophularia/química , Raízes de Plantas/química , Controle de Qualidade
7.
Zhongguo Zhong Yao Za Zhi ; 43(5): 891-896, 2018 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-29676084

RESUMO

To prepare the standard decoction of Moutan Cortex, and research its quality standard. According to the preparation principle of standard decoction of Chinese herbal medicines, the extraction conditions were optimized, and the 14 batches of standard decoction of Moutan Cortex were prepared. The content of paeonol was determined by HPLC; the transfer rate was calculated; and the extraction rate, pH value and the fingerprint of the decoction were determined. The results showed that the transfer rate of paeonol in the standard decoction of 14 batches of samples was at the range of 43.9%-67.3%; the range of extraction rate was 22.0%-38.7%, and the pH value range was 3.98-4.77. At the same time, the fingerprints of 14 batches of Moutan Cortex standard decoction were established; 9 common peaks were determined, and the similarities were more than 0.9. The preparation method in this study was standardized with good reproducibility, and can be used for the preparation and quality standard of standard decoction of Moutan Cortex, providing reference for the quality evaluation of Moutan Cortex dispensing granules.


Assuntos
Medicamentos de Ervas Chinesas/normas , Paeonia/química , Controle de Qualidade , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes
8.
Nat Prod Bioprospect ; 8(1): 47-56, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29285602

RESUMO

Six new triterpenoid saponins, aesculusosides A-F (1-6), together with 19 known ones, were isolated from the seeds of Aesculus chinensis. The new structures were elucidated through extensive spectroscopic analyses and by comparison with previously reported data. Some of the isolates were evaluated for their cytotoxic activities against MCF-7 cell line by an MTT assay, and compounds 15, 16, 19, and 23-25 exhibited inhibitory activities against MCF-7 with IC50 values ranging from 7.1 to 31.3 µM.

9.
Zhongguo Zhong Yao Za Zhi ; 42(17): 3356-3361, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29192446

RESUMO

Quality constant is a comprehensive grades evaluation method for traditional Chinese medicine decoction pieces, which is better but based on traditional way. In this paper, a new grading mode for Phellodendri chinensis pieces was established based on quality constant evaluation method. The results showed that the range of relative quality constant for 15 batches of different samples was from 0.41 to 0.96. As customary, if these samples were divided into three grades: the relative quality constant shall be ≥0.77 for first grade; <0.77 but ≥0.48 for the second grade; and <0.48 for the third grade. This research indicated that the quality constant mode can be used to effectively grade the P. chinensis pieces in a scientific, reasonable, objective and specific way. Simultaneously, it provided a beneficial reference for grading cortex herbal pieces or medicines.


Assuntos
Medicamentos de Ervas Chinesas/normas , Phellodendron/química , Medicina Tradicional Chinesa , Plantas Medicinais/química
10.
J Biol Phys ; 43(4): 493-510, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29124623

RESUMO

Gas-filled microbubbles attached to cell surfaces can interact with focused ultrasound to create microstreaming of nearby fluid. We directly observed the ultrasound/microbubble interaction and documented that under certain conditions fluorescent particles that were attached to the surface of live cells could be removed. Fluorescently labeled liposomes that were larger than 500 nm in diameter were attached to the surface of endothelial cells using cRGD targeting to αvß3 integrin. Microbubbles were attached to the surface of the cells through electrostatic interactions. Images taken before and after the ultrasound exposure were compared to document the effects on the liposomes. When exposed to ultrasound with peak negative pressure of 0.8 MPa, single microbubbles and groups of isolated microbubbles were observed to remove targeted liposomes from the cell surface. Liposomes were removed from a region on the cell surface that averaged 33.1 µm in diameter. The maximum distance between a single microbubble and a detached liposome was 34.5 µm. Single microbubbles were shown to be able to remove liposomes from over half the surface of a cell. The distance over which liposomes were removed was significantly dependent on the resting diameter of the microbubble. Clusters of adjoining microbubbles were not seen to remove liposomes. These observations demonstrate that the fluid shear forces generated by the ultrasound/microbubble interaction can remove liposomes from the surfaces of cells over distances that are greater than the diameter of the microbubble.


Assuntos
Adesão Celular , Lipossomos/isolamento & purificação , Lipossomos/metabolismo , Microbolhas , Ondas Ultrassônicas , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Ligantes , Eletricidade Estática , Propriedades de Superfície
11.
Zhongguo Zhong Yao Za Zhi ; 42(9): 1673-1678, 2017 May.
Artigo em Chinês | MEDLINE | ID: mdl-29082688

RESUMO

By measuring the morphological indexes and the marker components content of 22 batches of Scutellariae Radix slices as well as calculating the quality constant, this research was aimed to establish a new method of evaluating the specifications and grades of Scutellariae Radix slices. The quality constants of these samples were in the range of 0.04-0.49, which can be divided into several grades based on the real requirement. If they were divided into three grades, the quality constant was ≥0.39 for the first grade, <0.39 but ≥0.24 for the second grade, and <0.24 for the third grade. This work indicated that the quality constants characterizing both apparent parameters and intrinsic quality can be used as a comprehensive evaluation index to classify the grades of traditional Chinese medicine quantitatively, clearly and objectively. The research results in this paper would provide new ideas and references for evaluating the specifications and grades of traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas/normas , Scutellaria baicalensis , Medicina Tradicional Chinesa , Controle de Qualidade
12.
Radiology ; 276(2): 518-25, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25811427

RESUMO

PURPOSE: To determine whether (a) stem cells loaded with DNA-carrying microbubbles (MBs) can be transfected in vivo, (b) the cells remain alive to express the gene, and (c) gene expression is sufficiently robust to be detected in vivo. MATERIALS AND METHODS: The study was approved by the Institutional Animal Care and Use Committee. Cationic MBs were prepared, characterized, and loaded with pLuciferase green fluorescent protein (GFP) plasmid. Loading was confirmed with SYBR Gold staining (Life Technologies, Carlsbad, Calif). C17.2 cells were loaded with the DNA-carrying MBs. Two hundred thousand cells suspended in 20 µL phosphate-buffered saline were mixed with 200 µL Matrigel (BD Biosciences, San Jose, Calif) and injected in both flanks of eight nude mice. One of the Matrigel (BD Biosciences) injections contained 50 000 cells pretransfected in vitro by using lipofectamine as a positive control. Nine flanks were exposed to 2.25-MHz ultrasonic pulses at 50% duty cycle for 1 minute at 1 W/cm(2) (n = 3) or 2 W/cm(2) (n = 6), and six flanks served as the negative control. Two days later, bioluminescent images were acquired in each mouse every 3 minutes for 1 hour after the intraperitoneal injection of d-luciferin (Perkin Elmer, Waltham, Mass). Differences between groups were assessed by using the nonparametric Kruskal-Wallis test with Wilcoxon rank sum tests for follow-up comparisons. Mice were then killed, plugs were explanted, and alternate sections were stained with hematoxylin-eosin or stained for GFP expression. RESULTS: Mean DNA-loaded MB diameter ± standard deviation was 2.87 µm ± 1.69 with the DNA associated with the MB shell. C17.2 cells were associated with 2-4 MBs each, and more than 90% were viable. Peak background subtracted bioluminescent signal was fourfold higher when cells were exposed to 2 W/cm(2) pulses as compared with 1 W/cm(2) pulses (P = .02) and negative controls (P = .002). Histologic examination showed cells within the Matrigel (BD Biosciences) with robust GFP expression only after 2 W/cm(2) ultrasound exposure and lipofectamine transfection. CONCLUSION: Stem cells loaded with DNA-carrying MBs can be transfected in vivo with ultrasonic pulses and remain alive to demonstrate robust gene expression.


Assuntos
DNA/administração & dosagem , Expressão Gênica , Microbolhas , Células-Tronco , Transfecção/instrumentação , Transfecção/métodos , Animais , Células Cultivadas , Camundongos , Camundongos Nus
13.
Methods ; 64(2): 102-7, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23974072

RESUMO

With the emerging interest in personalized medicine, there is strong demand for new technologies for clinical sample interrogation. Exfoliated tumor cells in variety of pathological samples (e.g., blood, bone marrow, urine) could provide invaluable information for diagnosis and prognosis of cancers. Here we describe a detailed method for capture and isolation of tumor cells in medium, blood, or large issue buffy coat using EpCAM-targeted buoyant microbubbles (MBs). Perflorohexane gas lipid shell MBs were prepared with emulsification method and conjugated with antibody as described by us before [25]. The binding of EpCAM-targeted MBs to A549 (human lung carcinoma) and 4T1 (mouse breast carcinoma) cells spiked into BSA/PBS or blood was more than 90%, which was comparable with commercial anti-EpCAM immunomagnetic beads (DynaBeads). Anti-EpCAM MBs efficiently (75-82%) isolated BxPC3 pancreatic tumor cells spiked into medium, blood or a buffy coat, within 15-30 min of incubation. We discuss MB parameters and experimental conditions critical to achieve efficient cells binding and isolation. In conclusion, MB-assisted cell isolation is a promising method for rapid enrichment of cells and biomarkers from biological samples.


Assuntos
Separação Celular/métodos , Fluorocarbonos , Microbolhas , Células Neoplásicas Circulantes/patologia , Animais , Antígenos de Neoplasias/imunologia , Moléculas de Adesão Celular/imunologia , Linhagem Celular Tumoral , Células Imobilizadas/citologia , Molécula de Adesão da Célula Epitelial , Feminino , Humanos , Neoplasias Mamárias Animais/patologia , Camundongos
14.
Biomaterials ; 34(21): 4926-35, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23578557

RESUMO

Tracking neuroprogenitor cells (NPCs) that are used to target tumors, infarction or inflammation, is paramount for cell-based therapy. We employed ultrasound imaging that can detect a single microbubble because it can distinguish its unique signal from those of surrounding tissues. NPCs efficiently internalized positively charged microbubbles allowing a clinical ultrasound system to detect a single cell at 7 MHz. When injected intravenously, labeled NPCs traversed the lungs to be imaged in the left ventricle and the liver where they accumulated. Internalized microbubbles were not only less sensitive to destruction by ultrasound, but remained visible in vivo for days as compared to minutes when given free. The extended longevity provides ample time to allow cells to reach their intended target. We were also able to transfect NPCs in vitro when microbubbles were preloaded with GFP plasmid only when cells were insonated. Transfection efficiency and cell viability were both greater than 90%.


Assuntos
Meios de Contraste , Diagnóstico por Imagem/métodos , Microbolhas , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Coloração e Rotulagem , Ultrassom/métodos , Animais , Bromodesoxiuridina/metabolismo , DNA , Imunofluorescência , Limite de Detecção , Fígado/patologia , Camundongos , Camundongos Nus , Fenômenos Ópticos , Transfecção
15.
PLoS One ; 8(3): e58017, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23516425

RESUMO

Circulating tumor cells (CTCs) are exfoliated at various stages of cancer, and could provide invaluable information for the diagnosis and prognosis of cancers. There is an urgent need for the development of cost-efficient and scalable technologies for rare CTC enrichment from blood. Here we report a novel method for isolation of rare tumor cells from excess of blood cells using gas-filled buoyant immuno-microbubbles (MBs). MBs were prepared by emulsification of perfluorocarbon gas in phospholipids and decorated with anti-epithelial cell adhesion molecule (EpCAM) antibody. EpCAM-targeted MBs efficiently (85%) and rapidly (within 15 minutes) bound to various epithelial tumor cells suspended in cell medium. EpCAM-targeted MBs efficiently (88%) isolated frequent tumor cells that were spiked at 100,000 cells/ml into plasma-depleted blood. Anti-EpCAM MBs efficiently (>77%) isolated rare mouse breast 4T1, human prostate PC-3 and pancreatic cancer BxPC-3 cells spiked into 1, 3 and 7 ml (respectively) of plasma-depleted blood. Using EpCAM targeted MBs CTCs from metastatic cancer patients were isolated, suggesting that this technique could be developed into a valuable clinical tool for isolation, enumeration and analysis of rare cells.


Assuntos
Separação Imunomagnética/métodos , Microbolhas , Células Neoplásicas Circulantes , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Células Sanguíneas/imunologia , Células Sanguíneas/metabolismo , Moléculas de Adesão Celular/imunologia , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Humanos , Modelos Teóricos , Células Neoplásicas Circulantes/metabolismo , Ligação Proteica/imunologia
16.
Acta Biomater ; 5(2): 580-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18835227

RESUMO

When coaptation is not possible in the repair of nerve injuries, a bridge of biomaterial scaffold provides a structural support for neuronal cell growth and guides nerve regeneration. Poly(lactide-co-glycolide) (PLGA) scaffolds have been widely investigated for neural tissue engineering applications. In order to investigate guided neurite growth, we have fabricated micropatterns on PLGA films using laser ablation methods. The micropatterned PLGA films were coated with collagen type I or laminin peptide (PPFLMLLKGSTR) to promote axon growth. Micropatterned PLGA films provide a guidance effect on both early stage neurite outgrowth and elongation. Small (5 microm) grooves showed more statistically significant parallel neurite growth compared with larger size grooves (10 microm). Micropatterned PLGA films coated with laminin peptide showed more parallel neurite growth compared with those coated with collagen type I. Primary neurite number and total neurite length per cell decreased on micropatterned PLGA films compared with the controls. Neurites showed a preference for growth in the microgrooves rather than on the spaces. This study indicates that surface micropatterned structures with conjugated functional molecules can be used to guide neurite growth.


Assuntos
Ácido Láctico , Neuritos , Neurônios/citologia , Ácido Poliglicólico , Animais , Divisão Celular , Células PC12 , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Engenharia Tecidual
17.
Biomaterials ; 28(1): 9-18, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16952394

RESUMO

In this study, biodegradable poly(lactide-co-glycolide) (PLGA) (70/30) films and scaffolds were first treated with oxygen plasma and then incubated in a modified simulated body fluid 1.5SBF0 to prepare a bone-like apatite layer. The formation of the apatite and its influence on osteoblast-like cells growth were investigated. It was found that the bone-like apatite formability of PLGA(70/30) was enhanced by plasma pretreatment. The changes of surface chemistry and surface topography induced by oxygen plasma treatment were both effective for apatite formation. The apatite formability increased with increasing plasma-treating time. Under a treating condition of 20 W for 30 min, oxygen plasma treatment could penetrate into the inner scaffold. After 6 days incubation, the apatite formed in plasma-treated scaffold was better distributed than in untreated scaffold, and the weight and mechanical strength of the plasma-treated scaffold were both enhanced. Compared with PLGA(70/30), the apatite layer formed on oxygen plasma-treated PLGA(70/30) surface enhanced adhesion and proliferation of OCT-1 osteoblast-like cell, but had no significant effect on cell's ALP activity at day 7. A prolonged investigation is being in process to further verify the bone-like apatite effects on osteogenic differentiation.


Assuntos
Apatitas/química , Líquidos Corporais/química , Osso e Ossos/química , Oxigênio/química , Plasma/química , Poliglactina 910/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Íons/química , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Poliglactina 910/farmacologia , Análise Espectral
18.
Biomaterials ; 27(28): 4923-33, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16759695

RESUMO

Tissue engineering using scaffold not only should have biodegradability and a certain 3D structure, but also its morphology structure should be mimetic to that of the repaired natural tissue. So to manufacture the scaffold with a biomimetic structure as the natural tissues is important. In this research, highly porous poly(L-lactic acid) (PLLA) and poly(L-lactic-co-glycolic acid) (PLGA) scaffolds with microtubules orientation structure were designed and fabricated by using dioxane as solvent and an improved thermal-induced phase separation (TIPS) technique. All the factors which will affect solvent crystallization and microtubules orientation structure of the scaffold, such as the type of the solvent and polymer, concentration of the polymer solution, and temperature-gradient of the system have been studied carefully. So the porosity, diameter, tubular morphology and orientation of the microtubules could be controlled by adjusting the concentration of the polymer solution and temperature-gradient of the system. The scaffold with diameter of microtubules from 40 to 240microm and high porosity up to 96% could be obtained by adjusting temperature-gradient during the TIPS process. By increasing concentration of the polymer solution the regularity of the microtubular scaffold has been improved and the thickness of wall of the microtubules has been increased as well. In vitro cell culture results show that after the scaffolds have been improved by the ammonia plasma treatment and then collagen anchorage method, the human transparent cartilage cells H144, could be seeded deeply into the microtubules orientation-structured scaffolds and grew well there.


Assuntos
Microtúbulos/metabolismo , Poliésteres/química , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cartilagem/citologia , Células Cultivadas , Fracionamento Químico , Humanos , Ácido Láctico/química , Microscopia Eletrônica de Varredura , Microtúbulos/efeitos dos fármacos , Microtúbulos/ultraestrutura , Concentração Osmolar , Poliésteres/farmacologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/química , Porosidade , Estresse Mecânico , Propriedades de Superfície , Temperatura , Engenharia Tecidual/instrumentação
19.
Biomaterials ; 27(2): 216-25, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16054684

RESUMO

Porcine-derived xenogeneic bone (PDXB) was derived from cancellous bone of adult porcine. Its morphology and structure were characterized by SEM, FTIR and XRD. A series of composite films consisting of PDXB and poly(glycolide-co-lactide-co-caprolactone) (PGLC) polymer were prepared. Because of the introduction of PGLC polymer, the PDXB/PGLC composites especially PDXB/PGLC(30/70) and PDXB/PGLC(50/50) showed good processability and mechanical properties. In addition, the hydrophilicity of the composites was enhanced as well since the PDXB component was hydrophilic. Osteoblast-like cells (OCT-1) were used as an in-vitro model to assess the affinity of the PDXB/PGLC composites. It was found that compared with the pure PGLC film, PDXB/PGLC(30/70) and PDXB/PGLC(50/50) composite films promoted cell attachment, proliferation and ALP (alkaline phosphatase) activity obviously. In addition, the cells preferred growing on the areas of exposed PDXB. It was considered that the hydrophilicity, osteoconductivity and appropriate surface roughness (Sa=3.30, 4.00 microm) induced by PDXB facilitate cell growth. However, the introduction of too much PDXB, such as PDXB/PGLC(70/30) film, would obtain an adverse effect on the cell growth since the value of Sa was up to 7.33 microm. It indicated that only the composites with appropriate surface topography could favor cell growth. Surface topography probably has a more important effect on cell growth process than surface chemistry.


Assuntos
Materiais Biocompatíveis/química , Osteoblastos/metabolismo , Poliésteres/química , Ácido Poliglicólico/química , Transplante Heterólogo , Animais , Substitutos Ósseos/química , Osso e Ossos/ultraestrutura , Linhagem Celular , Forma Celular , Teste de Materiais , Osteoblastos/citologia , Tamanho da Partícula , Ratos , Propriedades de Superfície , Suínos , Resistência à Tração , Engenharia Tecidual , Água/química
20.
Anal Bioanal Chem ; 381(3): 547-56, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15672238

RESUMO

This article reviews various methods of modifying the bulk and surface properties of poly(lactic acid) (PLA) so that the polymer may be used as a drug carrier in a drug delivery system (DDS) and as a cell scaffold in tissue engineering. Copolymerization of lactide with other lactone-type monomers or monomers with functional groups such as malic acid, copolymerization of lactide with macromolecular monomer such as poly(ethylene glycol) (PEG) or dextran, as well as blending polylactide and natural derivatives and other methods of bulk modification are discussed. Surface modifications of PLA-type copolymers, such as surface coating, chemical modification, and plasma treatment are described. Cell culture technology proves the efficiency of bulk and surface modification and the potential application of PLA in tissue engineering.


Assuntos
Poliésteres , Implantes Absorvíveis , Dextranos , Portadores de Fármacos , Polietilenoglicóis , Engenharia Tecidual/métodos
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