Polyglycolic Acid

聚乙醇酸
  • 文章类型: Journal Article
    背景:结直肠癌是全球常见疾病,具有粪便中的血液等非特异性症状,排便,体重减轻和疲劳。化疗药物会引起恶心等副作用,呕吐和免疫系统减弱。使用橙皮苷等抗氧化剂可以减少副作用,但其低生物利用度是一个主要问题。在这项研究中,我们的目的是通过将橙皮苷加载到PLGA纳米颗粒中,探索这种抗氧化剂在HCT116结直肠癌细胞系上的药物递送和效率。
    方法:通过单乳液蒸发法制备负载橙皮苷的PLGA纳米颗粒。合成的橙皮苷纳米粒的理化性质采用SEM,AFM,FT-IR,DLS和UV-Vis。随后,在三种不同浓度的纳米颗粒下,通过MTT法研究了负载PLGA的橙皮苷纳米颗粒在48h后对HCT116细胞系的影响。
    结果:研究表明,通过紫外-可见分光光度法和FT-IR光谱,PLGA纳米颗粒中负载了90%的橙皮苷。发现纳米颗粒为球形且均匀的,在水中具有76.2nm的流体动力学直径。144小时后,药物的释放率约为93%。在10µg/ml浓度的负载橙皮苷的PLGA纳米颗粒下,观察到癌细胞的细胞活力百分比最低。
    结论:结果表明,负载橙皮苷的PLGA纳米颗粒可有效降低HCT116大肠癌细胞的存活率。然而,需要进一步的研究来确定合适的治疗剂量,并进行动物和临床研究。
    BACKGROUND: Colorectal cancer is a common disease worldwide with non-specific symptoms such as blood in the stool, bowel movements, weight loss and fatigue. Chemotherapy drugs can cause side effects such as nausea, vomiting and a weakened immune system. The use of antioxidants such as hesperidin could reduce the side effects, but its low bioavailability is a major problem. In this research, we aimed to explore the drug delivery and efficiency of this antioxidant on the HCT116 colorectal cancer cell line by loading hesperidin into PLGA nanoparticles.
    METHODS: Hesperidin loaded PLGA nanoparticles were produced by single emulsion evaporation method. The physicochemical properties of the synthesized hesperidin-loaded nanoparticles were determined using SEM, AFM, FT-IR, DLS and UV-Vis. Subsequently, the effect of the PLGA loaded hesperidin nanoparticles on the HCT116 cell line after 48 h was investigated by MTT assay at three different concentrations of the nanoparticles.
    RESULTS: The study showed that 90% of hesperidin were loaded in PLGA nanoparticles by UV-Vis spectrophotometry and FT-IR spectrum. The nanoparticles were found to be spherical and uniform with a hydrodynamic diameter of 76.2 nm in water. The release rate of the drug was about 93% after 144 h. The lowest percentage of cell viability of cancer cells was observed at a concentration of 10 µg/ml of PLGA nanoparticles loaded with hesperidin.
    CONCLUSIONS: The results indicate that PLGA nanoparticles loaded with hesperidin effectively reduce the survival rate of HCT116 colorectal cancer cells. However, further studies are needed to determine the appropriate therapeutic dosage and to conduct animal and clinical studies.
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  • 文章类型: Journal Article
    抗氧化剂疗法在预防和管理眼部疾病如白内障方面是令人感兴趣的。虽然是一个活跃的兴趣领域,用抗氧化剂治疗白内障的局部治疗并发多个眼解剖障碍,产品稳定性,和溶解度。用聚(乳酸-共-乙醇酸)纳米颗粒包封和递送抗氧化剂是这些挑战的可能解决方案,然而,关于它们在体外或体内的作用知之甚少。我们的第一个目的是研究空白和叶黄素负载的PLGA纳米颗粒对体外晶状体上皮细胞中活性氧簇的活力和发育的影响。通过紫外线照射诱导光氧化应激,并监测细胞活力和活性氧。接下来,体内,亚硒酸盐模型用于诱导啮齿动物的白内障形成。用不同浓度的游离叶黄素和装载叶黄素的纳米颗粒(LNP)局部处理眼睛。监测眼睛的前节变化和白内障形成的发展。通过与房水样品的质谱联用的液相色谱和与晶状体的串联质谱联用的液相色谱(靶向LC-MS/MS)来评估纳米递送的叶黄素到达眼前段的能力。LNP在短暴露时间范围内(24小时)和浓度<0.2μgLNP/μl时对晶状体上皮细胞的活力影响最小。还注意到活性氧的发展显着减少。用相同叶黄素浓度为1,278μg/mL的LNP处理的动物显示白内障评分的最大降低。通过评估房水和晶状体样品评估来确认叶黄素向前段的递送。每天一次,持续一周,局部治疗与继发性角膜炎或前葡萄膜炎的发展无关。LNP可有效治疗白内障。
    Antioxidant therapies are of interest in the prevention and management of ocular disorders such as cataracts. Although an active area of interest, topical therapy with antioxidants for the treatment of cataracts is complicated by multiple ocular anatomical barriers, product stability, and solubility. Entrapment and delivery of antioxidants with poly(lactic-co-glycolic acid) nanoparticles is a possible solution to these challenges, however, little is known regarding their effects in vitro or in vivo. Our first aim was to investigate the impact of blank and lutein loaded PLGA nanoparticles on viability and development of reactive oxygen species in lens epithelial cells in vitro. Photo-oxidative stress was induced by ultraviolet light exposure with cell viability and reactive oxygen species monitored. Next, an in vivo, selenite model was utilized to induce cataract formation in rodents. Eyes were treated topically with both free lutein and lutein loaded nanoparticles (LNP) at varying concentrations. Eyes were monitored for the development of anterior segment changes and cataract formation. The ability of nanodelivered lutein to reach the anterior segment of the eye was evaluated by liquid chromatography coupled to mass spectrometry of aqueous humor samples and liquid chromatography coupled to tandem mass spectrometry (targeted LC-MS/MS) of lenses. LNP had a minimal impact on the viability of lens epithelial cells during the short exposure timeframe (24 h) and at concentrations < 0.2 μg LNP/μl. A significant reduction in the development of reactive oxygen species was also noted. Animals treated with LNPs at an equivalent lutein concentration of 1,278 μg /mL showed the greatest reduction in cataract scores. Lutein delivery to the anterior segment was confirmed through evaluation of aqueous humor and lens sample evaluation. Topical treatment was not associated with the development of secondary keratitis or anterior uveitis when applied once daily for one week. LNPs may be an effective in the treatment of cataracts.
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  • 文章类型: Journal Article
    我们研究了用作药物递送系统(DDS)的两种微胶囊的分子释放过程的单颗粒动力学:可生物降解的聚(乳酸-乙醇酸)(PLGA)和光触发的可降解脂质体封装金纳米球(脂质体-GNP)。优化DDS胶囊的设计,开发一种实时监控发布过程的方法是非常可取的。使用光学镊子和共聚焦荧光显微光谱的组合,我们成功地分析了溶液中单个光学捕获的PLGA颗粒和脂质体GNP。从荧光强度的时间衰减曲线来看,我们确定了释放过程的时间常数τ。我们证明了自发降解微胶囊(PLGA)的释放速率随着尺寸的增加而降低,而反过来,外部刺激可降解微胶囊(脂质体-GNP)的释放速率与其大小成正比。这一结果可以通过胶囊破坏机制的差异来解释,在纳秒脉冲激光照射下,PLGA发生水解,脂质体-GNP中的GNP发生光声效应。本方法提供了一种用于单一药物递送纳米载体的替代微分析系统的方法。
    We investigated the single particle kinetics of the molecular release processes from two types of microcapsules used as drug delivery systems (DDS): biodegradable poly(lactic-co-glycolic) acid (PLGA) and a light-triggered-degradable liposome encapsulating gold nanospheres (liposome-GNP). To optimize the design of DDS capsules, it is highly desirable to develop a method for real-time monitoring of the release process. Using a combination of optical tweezers and confocal fluorescence microspectroscopy we successfully analyzed a single optically trapped PLGA particle and liposome-GNPs in solution. From temporal decay profiles of the fluorescence intensity, we determined the time constant τ of the release processes. We demonstrated that the release rate of spontaneously degradable microcapsules (PLGA) decreased with increasing size, while conversely, the release rate of external stimuli-degradable microcapsules (liposome-GNPs) increased in proportion to their size. This result is explained by the differences in the disruption mechanisms of the capsules, with PLGA undergoing hydrolysis and the GNPs in the liposome-GNP undergoing a photoacoustic effect under nanosecond pulsed laser irradiation. The present approach offers a way forward to an alternative microanalysis system for single drug delivery nanocarriers.
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  • 文章类型: Journal Article
    目标:Neskeep®,可吸收的聚乙醇酸垫片,已被开发为垫片放置手术的最佳材料。然而,防止其严重粘连是一个至关重要的问题。因此,我们旨在使用大鼠模型确定Neskeep®的有效抗粘连剂。
    方法:使用60只大鼠进行动物实验,在腹壁上放置Neskeep®。使用了三种类型的抗粘连剂,建立四个亚组:Seprafilm®,INTERCEED®,AdSpray®,只有Neskeep®(对照)组。在术后第7、14和28天处死大鼠以评估Neskeep®周围的粘连水平具有Lauder评分的宏观视觉评估和组织病理学评估以评估粘连程度。
    结果:四组之间在第7天和第14天的劳德评分比例没有显着差异。组织学评估显示在任何观察时间组间没有显著差异。然而,在Neskeep®中,Lauder在第28天的平均得分分别为5.0、1.6、4.0和4.8,Seprafilm®,INTERCEED®,和AdSpray®组,分别。在第28天,Seprafilm®组中温和劳德评分的比例显著较高。
    结论:Seprafilm®与Neskeep®一起使用时可能表现出抗粘附作用。
    OBJECTIVE: Neskeep®, an absorbable polyglycolic acid spacer, has been developed as the optimal material for spacer placement surgery. However, preventing its severe adhesion is a crucial concern. Therefore, we aimed to identify an effective anti-adhesion agent for Neskeep® using rat models.
    METHODS: Animal experiments were performed using 60 rats, which underwent Neskeep® placement on the abdominal wall. Three types of anti-adhesion agents were employed, establishing four subgroups: Seprafilm®, INTERCEED®, AdSpray®, and only Neskeep® (control) groups. Rats were sacrificed on postoperative days 7, 14, and 28 to assess adhesion levels around the Neskeep® Macroscopic visual assessment with the Lauder score and histopathological evaluation were performed to assess the degree of adhesion.
    RESULTS: There were no significant differences in the proportion of Lauder scores on days 7 and 14 between the four groups. Histological evaluation revealed no significant differences between groups at any observation time. However, the mean Lauder scores at day 28 were 5.0, 1.6, 4.0, and 4.8 in the Neskeep®, Seprafilm®, INTERCEED®, and AdSpray® groups, respectively. The proportion of milder Lauder score was significantly higher in the Seprafilm® group on day 28.
    CONCLUSIONS: Seprafilm® may exhibit an anti-adhesive effect when used with Neskeep®.
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  • 文章类型: Journal Article
    目的:本研究评估了在植入新型层状聚乙醇酸(PGA)材料以替代大鼠气管中的临界尺寸缺损后,气管内施用碱性成纤维细胞生长因子(bFGF)对气管愈合的影响。
    方法:用PGA覆盖大鼠颈气管的临界尺寸缺损。将蒸馏水(DW)或3.125、6.25、12.5或25µgbFGF施用于气管2周(五组每组n=6)。纤毛再生区,纤毛搏动频率,测量PGA中心的纤毛运输功能。为了检查气管内施用bFGF的潜在副作用,对右下叶进行病理评估。
    结果:研究期间所有大鼠均存活。组织学检查显示2周后PGA材料上的纤毛上皮化。支气管镜检查显示,在施用高浓度bFGF(12.5和25µg)后,由于肉芽形成引起的狭窄。与DW组相比,给予3.125、6.25、12.5和25µgbFGF的组再生纤毛面积明显更大(15.2%,27.0%,41.3%,33.1%,和31.0%,分别为;p=0.00143),改善纤毛搏动频率(7.10、8.18、10.10、9.50和9.50Hz,分别),和改善纤毛运输功能(6.40、9.54、16.89、16.41和14.29µm/sec,分别)。右下叶的病理检查显示肺纤维化和增生,并伴有高浓度的bFGF(12.5和25µg)。
    结论:在植入人工气管后,以6.25µg的最佳剂量气管内施用bFGF可有效促进气管再生。
    OBJECTIVE: This study evaluated the effect of intratracheal administration of basic fibroblast growth factor (bFGF) on tracheal healing following implantation of a novel layered polyglycolic acid (PGA) material to replace a critical-size defect in rat trachea.
    METHODS: A critical-size defect in the rat cervical trachea was covered with PGA. Distilled water (DW) or 3.125, 6.25, 12.5 or 25 µg bFGF was administered into the trachea for 2 weeks (n = 6 for each of 5 groups). Regenerated areas of cilia, ciliary beat frequency and ciliary transport function (CTF) in the centre of the PGA were measured. To examine potential side effects of intratracheal administration of bFGF, the right lower lobe was pathologically evaluated.
    RESULTS: All rats survived during the study period. Histological examination showed ciliated epithelization on the PGA material after 2 weeks. Bronchoscopy revealed stenosis due to granulation following administration of high concentrations of bFGF (12.5 and 25 µg). Compared with the DW group, groups administered 3.125, 6.25, 12.5 and 25 µg bFGF had significantly larger areas of regenerated cilia (15.2%, 27.0%, 41.3%, 33.1% and 31.0%, respectively; P = 0.00143), improved ciliary beat frequency (7.10, 8.18, 10.10, 9.50 and 9.50 Hz, respectively), and improved CTS (6.40, 9.54, 16.89, 16.41 and 14.29 µm/sec, respectively). Pathological examination of the right lower lobe revealed pulmonary fibrosis and hyperplasia with high concentrations of bFGF (12.5 and 25 µg).
    CONCLUSIONS: Intratracheal administration of bFGF effectively promoted tracheal regeneration at an optimal dose of 6.25 µg following implantation of an artificial trachea.
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  • 文章类型: Journal Article
    慢性伤口形成的预防已经成为伤口管理的主要课题。特别是对于深的伤口。由于其微/纳米孔结构,电纺纳米纤维膜在预防慢性伤口方面具有巨大潜力。目前,许多天然和合成材料已用于制造纳米纤维膜。然而,在结构稳定性和生物相容性之间取得平衡仍然具有挑战性。不仅需要确保纳米纤维膜的长期耐久性,而且还需要增强其生物相容性以减轻患者的痛苦。在这项研究中,我们报道了一种具有优异的生物相容性和机械性能的纳米纤维膜敷料,这是治疗深层伤口的潜力。选择用于制备纳米纤维膜的基础材料是由非异氰酸酯聚氨酯(NIPU)和具有二羟基结构的聚乙醇酸(由乙醇酸和新戊二醇合成的LPGD)合成的共聚酯(NI-LPGD5)。此外,姜黄素也被添加作为生物活性物质以增强敷料的促愈合作用。通过各种物理化学工具表征了制备的纳米纤维膜的物理化学性质。我们的结果表明,NI-LPGD5共聚物可以静电纺丝成光滑的纤维。同时,负载姜黄素的纳米纤维膜(Cur/NI-LPGD5)也表现出有利的微观形态。制造的膜表现出合适的机械性能,优异的吸湿溶胀率和水蒸气透过率。此外,体外细胞培养,NI-LPGD5膜上的细胞保持其最大活力。通过动物实验进一步证明了体内伤口愈合的潜力。实验结果表明,纳米纤维膜可有效防止慢性伤口形成,并促进肉芽组织生长,而无需在整个愈合过程中更换敷料。我们还发现,这些纳米纤维膜可以有效促进相关生物标志物的表达,加速伤口愈合,特别是Cur/NI-LPGD5膜。总之,制备的膜具有合适的理化性质和有前途的生物活性。因此,它有效地防止慢性伤口的形成,并显示出减少换药频率的显着潜力。
    The prevention of chronic wound formation has already been a primary subject in wound management, particularly for deep wounds. The electrospun nanofiber membranes hold tremendous potential in the prevention of chronic wounds due to their micro/nano pore structures. Currently, many natural and synthetic materials have been utilized in the fabrication of nanofiber membranes. However, striking a balance between the structural stability and the biocompatibility remains challenging. It is necessary not only to ensure the long-term durability of nanofiber membranes but also to enhance their biocompatibility for alleviating patients\' suffering. In this study, we reported a nanofiber membrane dressing with excellent biocompatibility and mechanical properties, which is potential for the treatment of deep wounds. The basal material chosen for the preparation of the nanofiber membrane was a co-polyester (NI-LPGD5) synthesized by non-isocyanate polyurethane (NIPU) and polyglycolic acid with a dihydroxy structure (LPGD-synthesized from glycolic acid and neopentyl glycol). Moreover, curcumin was also added as a bioactive substance to enhance the pro-healing effect of dressings. The physicochemical properties of the prepared nanofiber membranes were characterized through various physicochemical tools. Our results demonstrated that the NI-LPGD5 co-polymer can be electrospun into smooth fibers. Meanwhile, curcumin-loaded nanofiber membranes (Cur/NI-LPGD5) also exhibited a favorable microscopic morphology. The fabricated membranes exhibited suitable mechanical properties, outstanding hygroscopic-swelling rate and water vapor transmittance. Besides, in vitro cell culturing, the cells on the NI-LPGD5 membrane maintained their maximum viability. The potential of in vivo wound healing was further demonstrated through animal experiments. The experimental results showed that the nanofiber membranes effectively prevented chronic wounds from forming and promoted granulation tissue growth without replacing the dressing throughout the healing process. We also found that these nanofiber membranes could effectively promote the expression of related biomarkers to accelerate wound healing, particularly the Cur/NI-LPGD5 membrane. In conclusion, the fabricated membranes possess suitable physicochemical properties and promising bioactivity. As a result, it effectively prevented the formation of chronic wounds and demonstrated significant potential in reducing the frequency of dressing changes.
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  • 文章类型: Journal Article
    本研究的目的是开发小檗碱(BBR)的新型制剂,并证明其在戊四氮(PTZ)诱导的大鼠点燃模型中的抗癫痫作用。使用聚乳酸-共-乙醇酸(PLGA)作为聚合物配制BBR的纳米颗粒。采用乳化和溶剂蒸发技术。用PTZ诱导的雄性wistar大鼠点燃模型证明了纳米BBR的抗惊厥作用。最终制剂获得的粒度为242.8±67.35nm,PDI为0.140±0.01。PLGA包封的BBR纳米颗粒显示出87.33±2.42%的%包封效率和48.47±1.34%的%载药量。与BBR相比,体外药物释放数据显示纳米BBR的持续释放。动力学研究数据显示纳米BBR的AUC增加(35,429.46小时。ng/ml)与BBR(28,211.07小时。ng/ml)。纳米BBR的Cmax(2251.90ng/ml)是BBR(1505.50ng/ml)的大约1.6倍。纳米BBR已显示出对癫痫发作评分的显著影响。PLGA包裹的小檗碱纳米颗粒是通过一种创新的简单方法制备的,具有出色的抗癫痫药潜力。
    The aim of the present study was to develop a novel formulation of berberine (BBR) and demonstrate its anti-seizure effect in pentylenetetrazole (PTZ) induced kindling model in rats. Nanoparticles of BBR were formulated using Poly Lactic-co-Glycolic Acid (PLGA) as a polymer. Emulsification and solvent evaporation technique was used. PTZ induced kindling model in male wistar rat was used to demonstrate the anti-seizure effect of nano-BBR. The particle size obtained for the final formulation was 242.8 ± 67.35 nm with a PDI of 0.140 ± 0.01. PLGA encapsulated BBR nanoparticles showed the % encapsulation efficiency of 87.33 ± 2.42 % and % drug loading of 48.47 ± 1.34 %. In-vitro drug release data showed sustained release of nano-BBR as compared to BBR. Kinetic study data showed increase in AUC of nano-BBR (35,429.46 h.ng/ml) as compared to BBR (28,211.07 h.ng/ml). Cmax for nano- BBR (2251.90 ng/ml) is approximately 1.6 times greater than BBR (1505.50 ng/ml). Nano- BBR has shown the significant effect on the seizure score. The PLGA encapsulated berberine nanoparticles were prepared by an innovative simple method and offers excellent potential as an antiepileptic agent.
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  • 文章类型: Journal Article
    背景:坐骨神经修复成为神经系统研究的焦点,以恢复动物站立和行走的正常身体能力。组织工程神经移植物(TENGs)为大间隙缺损的再生提供了一种有前途的替代疗法。本研究调查了PRP的再生能力,ADSCs,和PRP混合的ADSCs在通过作为神经支架的聚乙醇聚丙烯(PGA-PRL)网桥接的长坐骨神经缺损(40毫米)上。
    方法:该研究对12只成年雄性杂种犬进行,随机分为4组:I组(支架组);其中仅通过(PGA-PRL)网状物桥接坐骨缺损,而在II组(ADSCs组)中,网状物注射ADSCs,第三组PRP(PRP组)。将PRP和ADSCs的混合物分配在组IV(PRP+ADSCs组)中。每月,监测所有动物的步态改善情况,并记录所有组的数字跛行评分.手术后6个月,坐骨神经的结构和功能恢复进行电生理评估,在基因表达水平上,坐骨神经和腓肠肌都进行了形态计量学评估,组织病理学。
    结果:数值跛行评分显示,II组和III组的运动活动均有改善,IV组和支架组甚至在6个月后仍有轻度改善。组织病理学,所有治疗组均显示轴突发芽和大量再生束,近端切口有明显的血管生成,和远端部分,其中组IV表现出明显的髓鞘再生MCOOL技术。腓肠肌再生率为23.81%,56.68%,第一组为52.06%和40.69%,II,III和IV;分别。III组和IV组的NGF表达在近端部分均显示出显着的上调(P≤0.0001),而II组则没有显着差异。PDGF-A,和VEGF表达在II组中上调,III,和IV,而I组显示NGF的显着下调,PDGF-A,VEGF(P≤0.0001)。
    结论:ADSCs通过分泌几种类型的生长因子,如NGF,对雪旺细胞及其迁移具有增殖作用,在修复受损的神经纤维方面具有重要作用。此外,PRP疗法通过合成另一种生长因子如PDGF-A增强ADSCs的作用,VEGF,NGF用于较好地愈合年夜坐骨间隙缺损。
    BACKGROUND: Sciatic nerve repair becomes a focus of research in neurological aspect to restore the normal physical ability of the animal to stand and walk. Tissue engineered nerve grafts (TENGs) provide a promising alternative therapy for regeneration of large gap defects. The present study investigates the regenerative capacity of PRP, ADSCs, and PRP mixed ADSCs on a long sciatic nerve defect (40-mm) bridged by a polyglycolic polypropylene (PGA-PRL) mesh which acts as a neural scaffold.
    METHODS: The study was conducted on 12 adult male mongrel dogs that were randomly divided into 4 groups: Group I (scaffold group); where the sciatic defect was bridged by a (PGA-PRL) mesh only while the mesh was injected with ADSCs in Group II (ADSCs group), PRP in Group III (PRP group). Mixture of PRP and ADSCs was allocated in Group IV (PRP + ADSCs group). Monthly, all animals were monitored for improvement in their gait and a numerical lameness score was recorded for all groups. 6 months-post surgery, the structural and functional recovery of sciatic nerve was evaluated electrophysiologically, and on the level of gene expression, and both sciatic nerve and the gastrocnemius muscle were evaluated morphometrically, histopathologically.
    RESULTS: Numerical lameness score showed improvement in the motor activities of both Group II and Group III followed by Group IV and the scaffold group showed mild improvement even after 6 months. Histopathologically, all treated groups showed axonal sprouting and numerous regenerated fascicles with obvious angiogenesis in proximal cut, and distal portion where Group IV exhibited a significant remyelination with the MCOOL technique. The regenerative ratio of gastrocnemius muscle was 23.81%, 56.68%, 52.06% and 40.69% for Group I, II, III and IV; respectively. The expression of NGF showed significant up regulation in the proximal portion for both Group III and Group IV (P ≤ 0.0001) while Group II showed no significant difference. PDGF-A, and VEGF expressions were up-regulated in Group II, III, and IV whereas Group I showed significant down-regulation for NGF, PDGF-A, and VEGF (P ≤ 0.0001).
    CONCLUSIONS: ADSCs have a great role in restoring the damaged nerve fibers by secreting several types of growth factors like NGF that have a proliferative effect on Schwann cells and their migration. In addition, PRP therapy potentiates the effect of ADSCs by synthesis another growth factors such as PDGF-A, VEGF, NGF for better healing of large sciatic gap defects.
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  • 文章类型: Journal Article
    伊马替尼是已知在全身给药时引起严重副作用的化学治疗剂。将伊马替尼封装在共聚物聚(乳酸-共-乙醇酸)(PLGA)纳米颗粒(NP)中提供靶向药物递送。在这项工作中,PLGA50:50和PLGA75:25NP使用电流体动力雾化技术包封伊马替尼。产生的所有颗粒都是球形的,具有光滑表面,尺寸分布为455±115nm(PLGA50:50)和363±147nm(PLGA75:25)。伊马替尼的包封显示高于75%,并且显示增加负载的NP的ζ电位。伊马替尼的释放在最初的12小时内显示出最初的爆发,不同的持续释放高达70%。还在A549细胞上研究了两种类型的伊马替尼负载的NPs对细胞活力及其细胞摄取的影响,抗增殖作用与用游离药物处理的细胞相当。最后,负载罗丹明B的NP处理的细胞证明了NP的细胞摄取。
    Imatinib is a chemotherapeutic agent known to cause severe side effects when administrated systemically. Encapsulating imatinib in co-polymer poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) offers a targeted drug delivery. In this work, PLGA 50:50 and PLGA 75:25 NPs encapsulated imatinib using the electrohydrodynamic atomisation technique. All particles generated were spherical with a smooth surface with a size distribution of 455±115 nm (PLGA 50:50) and 363±147 nm (PLGA 75:25). Encapsulation of imatinib was shown to be higher than 75 % and was shown to increase the zeta potential of the loaded NPs. The release of imatinib showed an initial burst in the first 12 h, followed by different sustained releases with up to 70 %. Both types of imatinib-loaded NPs\' effect on cell viability and their cellular uptake were also studied on A549 cells, and the antiproliferative effect was comparable to that of cells treated with free drugs. Finally, Rhodamine-B-loaded NP-treated cells demonstrated the cellular uptake of NPs.
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  • 文章类型: Journal Article
    聚(丙交酯-共-乙交酯)(PLGA)的端基在确定用于药物递送系统的聚合物的性质中起重要作用。例如,据报道,在PLGA微球中的包封效率在酯封端的和酸封端的PLGA之间显著不同。更重要的是,这种聚合物赋形剂的体内降解时间受所用共聚物的官能端基的影响。已使用电喷雾和基质辅助激光解吸/电离-高分辨率质谱研究了PLGA聚合物中的端基分布。在这两种情况下,这些方法的应用通常限于分子量高达4kDa的PLGA。13碳-核磁共振也已被报道为区分和量化分子量高达136kDa的PLGA端基的方法。然而,报告的NMR方法每个样品需要超过12小时,限制吞吐量。冷冻探针核磁共振可以减少过程所需的时间,然而这样的核磁共振设备是昂贵的,这使得它不适合PLGA的质量控制。这里,我们提出了一种能够解析功能类型分布(FTD)的正相液相色谱方法,部分,从开环聚合获得的商业PLGA聚合物中的化学组成分布(CCD)。该方法可以分离分子量高达183.0kDa的PLGA聚合物,同时还可以同时分离乳酸(LA)/乙醇酸(GA)比率的差异。为了实现这一点,使用交联二醇柱,从HEX到EA中的0.1%v/vTEA到THF中的0.1%v/vFA的三元梯度,以允许首先洗脱单酯封端的PLGA,随后是二酸终止。此外,在LA/GA比率的差异中实现了酯封端的PLGA的分离。这种方法有望帮助理解PLGA的FTD之间的相关性,CCD,和物理性质,促进产品开发和质量控制。
    End groups of poly(Lactide-co-glycolide) (PLGA) play an important role in determining the properties of polymers for use in drug delivery systems. For instance, it has been reported that the encapsulation efficiency in PLGA microspheres varies significantly between ester-terminated and acid-terminated PLGA. More importantly, the in-vivo degradation time of such polymer excipients is influenced by the functional end-group of the copolymer used. The end group distribution in PLGA polymers has been studied using electrospray and matrix-assisted laser-desorption/ionization - high-resolution mass spectrometry. In both cases, the application of these methods is typically limited to PLGA having a molecular weight of up to 4 kDa. 13Carbon-nuclear-magnetic-resonance has also been reported as a method to differentiate and quantify PLGA end groups with a molecular weight up to 136 kDa. However, reported NMR methods take over 12 h per sample, limiting throughput.Cryoprobe NMR can reduce the time required for the process, however such NMR equipment is costly, which makes it unsuitable for the quality control of PLGA. Here, we present a normal-phase liquid chromatography method capable of resolving functionality type distribution (FTD) and, partially, chemical composition distribution (CCD) in commercial PLGA polymers obtained from ring opening polymerization. This method can separate PLGA polymers with a molecular weight of up to 183.0 kDa while also enabling the simultaneous separation of the difference of Lactic acid (LA)/Glycolic acid (GA) ratios. To achieve this, a cross-linked diol column was used with a ternary gradient from HEX to 0.1 % v/v TEA in EA to 0.1 % v/v FA in THF to allow first for the elution of mono-ester terminated PLGA, followed by the di-acid terminated. In addition, a separation of ester-terminated PLGA in the difference of the LA/GA ratio was achieved. This method is expected to aid in understanding the correlation between PLGA\'s FTD, CCD, and physical properties, facilitating product development and quality control.
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