PLGA, Poly (lactic-co-glycolic acid)

PLGA,聚乳酸 - 乙醇酸共聚物
  • 文章类型: Journal Article
    眼科手术和COVID-19患者中最常见的疾病是真菌性眼部感染,这可能会导致炎症和干眼症,并可能导致眼部发病。两性霉素B滴眼液通常用于治疗眼部真菌感染。乳铁蛋白是一种具有广谱抗微生物活性的铁结合糖蛋白,用于治疗干眼症,结膜炎,和眼部炎症。然而,不良的房水稳定性和过度的鼻泪管引流阻碍了这些药物的效率。这项研究的目的是检查两性霉素B的作用,作为抗白色念珠菌的抗真菌药,镰刀菌,还有黄曲霉,和乳铁蛋白,作为抗炎和抗干眼症,当共负载三嵌段聚合物PLGA-PEG-PEI纳米颗粒包埋在P188-P407眼科热敏凝胶中时。通过双乳液溶剂蒸发法制备纳米颗粒。优化后的配方显示粒径(177.0±0.3nm),多分散指数(0.011±0.01),ζ电位(31.9±0.3mV),和包封%(90.9±0.5),改善了离体药代动力学参数和离体角膜穿透性,与药物溶液相比。共聚焦激光扫描显示了氟标记的纳米颗粒的有价值的渗透。刺激试验(Draize试验),原子力显微镜,细胞培养和动物试验,包括组织病理学分析,揭示了纳米颗粒在减少炎症迹象和根除兔真菌感染方面的优越性。不会对兔子的眼球造成任何伤害。纳米颗粒表现出良好的药效学特征和持续释放曲线,并且在体外或体内既无细胞毒性也无刺激性。开发的配方可能为治疗眼部问题提供一种新的安全的纳米技术,比如炎症和真菌感染.
    The most prevalent conditions among ocular surgery and COVID-19 patients are fungal eye infections, which may cause inflammation and dry eye, and may cause ocular morbidity. Amphotericin-B eye drops are commonly used in the treatment of ocular fungal infections. Lactoferrin is an iron-binding glycoprotein with broad-spectrum antimicrobial activity and is used for the treatment of dry eye, conjunctivitis, and ocular inflammation. However, poor aqueous stability and excessive nasolacrimal duct draining impede these agens\' efficiency. The aim of this study was to examine the effect of Amphotericin-B, as an antifungal against Candida albicans, Fusarium, and Aspergillus flavus, and Lactoferrin, as an anti-inflammatory and anti-dry eye, when co-loaded in triblock polymers PLGA-PEG-PEI nanoparticles embedded in P188-P407 ophthalmic thermosensitive gel. The nanoparticles were prepared by a double emulsion solvent evaporation method. The optimized formula showed particle size (177.0 ± 0.3 nm), poly-dispersity index (0.011 ± 0.01), zeta-potential (31.9 ± 0.3 mV), and entrapment% (90.9 ± 0.5) with improved ex-vivo pharmacokinetic parameters and ex-vivo trans-corneal penetrability, compared with drug solution. Confocal laser scanning revealed valuable penetration of fluoro-labeled nanoparticles. Irritation tests (Draize Test), Atomic force microscopy, cell culture and animal tests including histopathological analysis revealed superiority of the nanoparticles in reducing signs of inflammation and eradication of fungal infection in rabbits, without causing any damage to rabbit eyeballs. The nanoparticles exhibited favorable pharmacodynamic features with sustained release profile, and is neither cytotoxic nor irritating in-vitro or in-vivo. The developed formulation might provide a new and safe nanotechnology for treating eye problems, like inflammation and fungal infections.
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  • 文章类型: Journal Article
    化学抗性以及由此产生的治疗失败在临床癌症治疗中是相当具有挑战性的。对化学抗性获得中的遗传变异的理解鼓励了使用基因调节方法来恢复抗癌药物的功效。许多智能纳米粒子被设计和优化以介导核酸和抗癌药物之间的组合治疗。这篇综述旨在定义这种共负载纳米载体的合理设计,目的是在各种细胞水平上逆转化学抗性,以改善抗癌治疗的治疗效果。通过治疗加载的原则,物理化学特性调整,和不同的纳米载体修饰,还研究了联合药物对化学敏感性恢复的有效性。到目前为止,这些新兴的纳米载体处于发展状态,但有望带来出色的成果。
    Chemoresistance and hence the consequent treatment failure is considerably challenging in clinical cancer therapeutics. The understanding of the genetic variations in chemoresistance acquisition encouraged the use of gene modulatory approaches to restore anti-cancer drug efficacy. Many smart nanoparticles are designed and optimized to mediate combinational therapy between nucleic acid and anti-cancer drugs. This review aims to define a rational design of such co-loaded nanocarriers with the aim of chemoresistance reversal at various cellular levels to improve the therapeutic outcome of anticancer treatment. Going through the principles of therapeutics loading, physicochemical characteristics tuning, and different nanocarrier modifications, also looking at combination effectiveness on chemosensitivity restoration. Up to now, these emerging nanocarriers are in development status but are expected to introduce outstanding outcomes.
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  • 文章类型: Journal Article
    由于自我修复能力有限,大型骨缺损修复是一个具有挑战性的临床问题。精心设计的骨填充产品应具有诱导组织向内生长并促进新血管形成和新骨形成的能力。葛根素已经在临床上使用了很长时间,最近发现它能够促进成骨。本研究旨在探讨以葛根素为基础的药物/递送组合植入物促进大型骨缺损修复。
    将葛根素掺入聚(乳酸-羟基乙酸共聚物)/β-磷酸钙(PLGA/TCP,PT)采用低温快速成型技术形成多孔PLGA/TCP/葛根素(PTP)复合支架。体外分析了其结构和降解。然后我们采用大鼠颅骨临界尺寸缺损模型来评估PTP支架的效力。MC3T3-E1细胞和EA.Hy926个细胞用于研究其潜在机制。
    PTP支架继承了PT支架在结构、机械,和生物降解,同时葛根素从PTP支架中稳定持续释放,并在体外持续5个月。植入后8周,PTP支架在支架的大孔和支架内部引发了新的骨形成,并伴随着降解材料。其潜在机制揭示了PTP支架通过刺激血管内皮生长因子(VEGF)和骨形态发生蛋白2(BMP-2)的表达促进血管生成和成骨,从而诱导血管浸润和募集修复细胞。
    富含葛根素的多孔PTP支架是一种有前途的局部递送系统,可持续释放葛根素,通过协同血管生成和成骨作用促进缺损修复。
    PTP支架为大型骨缺损修复提供了潜在的药物/设备组合医疗植入物,这也为“老药”葛根素提供了新的创新应用。
    UNASSIGNED: Large bone defect repair is a challenging clinical problem due to limited self-repair ability. A well-designed bone filling product should possess the ability to induce tissue in-growth and facilitate neovascularization and new bone formation. Puerarin has been used in clinics for a long time, and recently it was found to be able to promote osteogenesis. This study aimed to investigate a puerarin-based drug/delivery combination implant for promoting large bone defect repair.
    UNASSIGNED: Puerarin was incorporated into the poly (lactic-co-glycolic acid)/β-calcium phosphate (PLGA/TCP, PT) to form a porous PLGA/TCP/Puerarin (PTP) composite scaffold by low-temperature rapid prototyping technology. Its structural and degradation were analyzed in vitro. Then we employed a rat calvarial critical size defect model to assess the potency of the PTP scaffold. MC3T3-E1 cells and EA. hy 926 ​cells were used to investigate the underlying mechanism.
    UNASSIGNED: PTP scaffold inherited all advantages of PT scaffold in structural, mechanical, and biodegradation, meanwhile puerarin stably and continuously released from PTP scaffold and lasted for 5 months in vitro. At 8 weeks after implantation, the PTP scaffold triggered new bone formation in the macro-pores of the scaffold and inside the scaffold accompanied by the degrading materials. The underlying mechanism revealed that the PTP scaffold induced vascular infiltration and recruit repair cells through stimulating vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2) expressions to promote angiogenesis and osteogenesis.
    UNASSIGNED: Puerarin-enriched porous PTP scaffold was a promising local delivery system with sustained release of puerarin for facilitating defect repair through getting synergistic angiogenic and osteogenic effects.
    UNASSIGNED: The PTP scaffold presents a potential drug/device combination medical implant for large bone defect repair, which also provides a new and innovative application for the \"old drug\" puerarin.
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  • 文章类型: Journal Article
    组织工程神经移植物(TENGs)是修复长距离周围神经缺损的最有希望的方法。壳聚糖和聚(乳酸-羟基乙酸共聚物)(PLGA)支架被认为是制药和生物医学领域特别是组织工程领域的有前途的材料。为了进一步阐明插入各种数量的聚(乳酸-乙醇酸共聚物)(PLGA)支架的壳聚糖导管的效果,以及它们对周围神经再生的降解,采用壳聚糖神经导管插入不同数量的PLGA支架修复大鼠坐骨神经缺损。对不同时间点的周围神经再生进行动态综合评价。此外,还揭示了不同量的PLGA支架对再生微环境包括炎症反应和细胞状态的影响。适度丰富的PLGA对神经再生的成功更有帮助,这在再生神经的结构方面得到了证明,目标肌肉的神经支配,神经冲动传导,和整体功能。PLGA支架有助于施万细胞的迁移和成熟。此外,PLGA和壳聚糖降解产物以正确的比例中和,降低炎症反应,增强再生微环境。由适当的PLGA支架和壳聚糖导管的降解物调节的平衡微环境促进周围神经再生。这些发现代表了朝着规划TENGs建设迈出的又一步,聚酯材料在再生医学中的应用,了解神经再生微环境。
    Tissue-engineered nerve grafts (TENGs) are the most promising way for repairing long-distance peripheral nerve defects. Chitosan and poly (lactic-co-glycolic acid) (PLGA) scaffolds are considered as the promising materials in the pharmaceutical and biomedical fields especially in the field of tissue engineering. To further clarify the effects of a chitosan conduit inserted with various quantity of poly (lactic-co-glycolic acid) (PLGA) scaffolds, and their degrades on the peripheral nerve regeneration, the chitosan nerve conduit inserted with different amounts of PLGA scaffolds were used to repair rat sciatic nerve defects. The peripheral nerve regeneration at the different time points was dynamically and comprehensively evaluated. Moreover, the influence of different amounts of PLGA scaffolds on the regeneration microenvironment including inflammatory response and cell state were also revealed. The modest abundance of PLGA is more instrumental to the success of nerve regeneration, which is demonstrated in terms of the structure of the regenerated nerve, reinnervation of the target muscle, nerve impulse conduction, and overall function. The PLGA scaffolds aid the migration and maturation of Schwann cells. Furthermore, the PLGA and chitosan degradation products in a correct ratio neutralize, reducing the inflammatory response and enhancing the regeneration microenvironment. The balanced microenvironment regulated by the degradants of appropriate PLGA scaffolds and chitosan conduit promotes peripheral nerve regeneration. The findings represent a further step towards programming TENGs construction, applying polyester materials in regenerative medicine, and understanding the neural regeneration microenvironment.
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  • 文章类型: Journal Article
    新的中风患者的绝对数量每年都在增加,并且仍然只有少数食品和药物管理局(FDA)批准的治疗方法对患者有效。丹参酮IIA(TanIIA)是缺血性中风的有希望的潜在治疗剂,在临床前啮齿动物研究中已显示出成功,但在人类患者中导致不一致的疗效结果。Tan-IIA的物理性质,包括短半衰期和低溶解度,提示聚(乳酸-共-乙醇酸)(PLGA)纳米颗粒辅助递送可导致改善生物利用度和治疗功效。这项研究的目的是开发负载TanIIA的纳米颗粒(TanIIA-NP),并评估其对猪缺血性中风模型中脑病理变化和随之而来的运动功能缺陷的治疗作用。
    TanIIA-NP处理的神经干细胞在证明抗氧化作用的体外测定中显示SOD活性降低。与仅用载体处理的猪相比,用TanIIA-NP处理的缺血性中风猪显示出减少的半球肿胀(7.85±1.41vs.16.83±0.62%),随之而来的中线偏移(MLS)(1.72±0.07vs.2.91±0.36mm),和缺血性病变体积(9.54±5.06vs.12.01±0.17cm3),与仅用载体处理的猪相比。治疗还导致扩散率降低(-37.30±3.67vs.-46.33±0.73%)和白质完整性(-19.66±5.58vs.-30.11±1.19%)以及缺血性中风后24小时出血减少(0.85±0.15vs2.91±0.84cm3)。此外,TanIIA-NP导致12岁时循环带中性粒细胞百分比降低(7.75±1.93vs.14.00±1.73%)和卒中后24小时(4.25±0.48vs5.75±0.85%)提示炎症反应减轻。此外,时空步态缺陷,包括节奏,周期时间,步进时间,周期的摆动百分比,步幅长度,与对照猪相比,TanIIA-NP治疗的猪中风后相对平均压力变化较轻。
    这一概念验证研究的结果强烈表明,在卒中后急性期施用TanIIA-NP可能通过限制自由基形成来减轻神经损伤,从而在转化猪缺血性卒中模型中导致不太严重的步态缺陷。中风是美国功能性残疾的主要原因之一,步态缺陷是一个主要组成部分,这些有前景的结果表明,TanIIA-NP急性给药可能改善许多未来卒中患者的功能结局和生活质量.
    UNASSIGNED: The absolute number of new stroke patients is annually increasing and there still remains only a few Food and Drug Administration (FDA) approved treatments with significant limitations available to patients. Tanshinone IIA (Tan IIA) is a promising potential therapeutic for ischemic stroke that has shown success in pre-clinical rodent studies but lead to inconsistent efficacy results in human patients. The physical properties of Tan-IIA, including short half-life and low solubility, suggests that Poly (lactic-co-glycolic acid) (PLGA) nanoparticle-assisted delivery may lead to improve bioavailability and therapeutic efficacy. The objective of this study was to develop Tan IIA-loaded nanoparticles (Tan IIA-NPs) and to evaluate their therapeutic effects on cerebral pathological changes and consequent motor function deficits in a pig ischemic stroke model.
    UNASSIGNED: Tan IIA-NP treated neural stem cells showed a reduction in SOD activity in in vitro assays demonstrating antioxidative effects. Ischemic stroke pigs treated with Tan IIA-NPs showed reduced hemispheric swelling when compared to vehicle only treated pigs (7.85 ± 1.41 vs. 16.83 ± 0.62%), consequent midline shift (MLS) (1.72 ± 0.07 vs. 2.91 ± 0.36 mm), and ischemic lesion volumes (9.54 ± 5.06 vs. 12.01 ± 0.17 cm3) when compared to vehicle-only treated pigs. Treatment also lead to lower reductions in diffusivity (-37.30 ± 3.67 vs. -46.33 ± 0.73%) and white matter integrity (-19.66 ± 5.58 vs. -30.11 ± 1.19%) as well as reduced hemorrhage (0.85 ± 0.15 vs 2.91 ± 0.84 cm3) 24 h post-ischemic stroke. In addition, Tan IIA-NPs led to a reduced percentage of circulating band neutrophils at 12 (7.75 ± 1.93 vs. 14.00 ± 1.73%) and 24 (4.25 ± 0.48 vs 5.75 ± 0.85%) hours post-stroke suggesting a mitigated inflammatory response. Moreover, spatiotemporal gait deficits including cadence, cycle time, step time, swing percent of cycle, stride length, and changes in relative mean pressure were less severe post-stroke in Tan IIA-NP treated pigs relative to control pigs.
    UNASSIGNED: The findings of this proof of concept study strongly suggest that administration of Tan IIA-NPs in the acute phase post-stroke mitigates neural injury likely through limiting free radical formation, thus leading to less severe gait deficits in a translational pig ischemic stroke model. With stroke as one of the leading causes of functional disability in the United States, and gait deficits being a major component, these promising results suggest that acute Tan IIA-NP administration may improve functional outcomes and the quality of life of many future stroke patients.
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  • 文章类型: Journal Article
    背景:这项研究的目的是设计一种癌症侵袭模型,其中可以在体外调节癌症侵袭率。
    方法:制备含有各种浓度的转化生长因子-β1(TGF-β1)(CAF-GM-TGF-β1)的明胶水凝胶微球(GM)的癌相关成纤维细胞(CAF)聚集体。测量CAF聚集体的α-平滑肌肌动蛋白(α-SMA)以通过改变TGF-β1的浓度来研究CAF活化水平。通过将癌细胞与各种CAF-GM-TGF-β1共培养来进行侵袭测定以评估癌症侵袭率。
    结果:CAF中α-SMA的表达水平随着TGF-β1浓度的增加而增加。当与各种类型的CAF-GM-TGF-β1共培养时,癌症侵袭率与α-SMA水平密切相关。可以想象,TGF-β1浓度可以改变CAF活化的水平,导致癌细胞的侵袭率。此外,在高浓度的TGF-β1下,观察到基质金属蛋白酶(MMP)抑制剂对癌症侵袭率的影响。较高的侵袭率将通过较高的MMP产量来实现。
    结论:本模型有望实现通过改变TGF-β1浓度来改变其速率的癌症侵袭。
    BACKGROUND: The objective of this study is to design a cancer invasion model where the cancer invasion rate can be regulated in vitro.
    METHODS: Cancer-associated fibroblasts (CAF) aggregates incorporating gelatin hydrogel microspheres (GM) containing various concentrations of transforming growth factor-β1 (TGF-β1) (CAF-GM-TGF-β1) were prepared. Alpha-smooth muscle actin (α-SMA) for the CAF aggregates was measured to investigate the CAF activation level by changing the concentration of TGF-β1. An invasion assay was performed to evaluate the cancer invasion rate by co-cultured of cancer cells with various CAF-GM-TGF-β1.
    RESULTS: The expression level of α-SMA for CAF increased with an increased in the TGF-β1 concentration. When co-cultured with various types of CAF-GM-TGF-β1, the cancer invasion rate was well correlated with the α-SMA level. It is conceivable that the TGF-β1 concentration could modify the level of CAF activation, leading to the invasion rate of cancer cells. In addition, at the high concentrations of TGF-β1, the effect of a matrix metalloproteinase (MMP) inhibitor on the cancer invasion rate was observed. The higher invasion rate would be achieved through the higher MMP production.
    CONCLUSIONS: The present model is promising to realize the cancer invasion whose rate can be modified by changing the TGF-β1 concentration.
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  • 文章类型: Journal Article
    从大自然中汲取灵感,仿生概念已被整合到癌症治疗的药物递送系统中。伪装细胞膜,纳米粒子可以获得天然细胞的各种功能。细胞膜涂层技术已经推动了常见纳米系统(循环中的快速消除)的限制,以更有效地在体内导航。此外,因为表面上的各种功能分子,基于细胞膜的纳米颗粒(CMBNPs)能够与肿瘤复杂的生物微环境相互作用。已经探索了各种来源的细胞膜来伪装CMBNP,并且已经开发了不同的肿瘤靶向策略来增强抗肿瘤药物递送疗法。在这篇综述文章中,我们重点介绍了基于CMBNP的癌症靶向系统的最新进展,并解决了该领域的挑战和机遇。
    Taking inspiration from nature, the biomimetic concept has been integrated into drug delivery systems in cancer therapy. Disguised with cell membranes, the nanoparticles can acquire various functions of natural cells. The cell membrane-coating technology has pushed the limits of common nano-systems (fast elimination in circulation) to more effectively navigate within the body. Moreover, because of the various functional molecules on the surface, cell membrane-based nanoparticles (CMBNPs) are capable of interacting with the complex biological microenvironment of the tumor. Various sources of cell membranes have been explored to camouflage CMBNPs and different tumor-targeting strategies have been developed to enhance the anti-tumor drug delivery therapy. In this review article we highlight the most recent advances in CMBNP-based cancer targeting systems and address the challenges and opportunities in this field.
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  • 文章类型: Journal Article
    疫苗接种,这提供了有效的,安全传染病防护,是最近最重要的公共卫生和免疫学成就之一。然而,传染病仍然是发展中国家死亡的主要原因,因为几种疫苗需要重复给药,儿童往往免疫不完全。基于微球的系统,提供控释递送,可以消除重复免疫的需要。这里,我们综述了生物可降解聚合物微球在胃肠外和粘膜单剂量疫苗给药中的持续和脉冲释放功能。我们还回顾了聚合物颗粒的活性靶向功能。凭借它们的屏蔽和共同交付功能,聚合物颗粒用于开发单剂量和粘膜施用的疫苗以及改进亚单位疫苗。由于聚合物颗粒易于表面改性,它们最近被用于癌症和许多传染病的疫苗开发,而没有有效的疫苗(例如,人类免疫缺陷病毒感染)。这些聚合物颗粒功能产生重要的疫苗载体和多种益处。
    Vaccination, which provides effective, safe infectious disease protection, is among the most important recent public health and immunological achievements. However, infectious disease remains the leading cause of death in developing countries because several vaccines require repeated administrations and children are often incompletely immunized. Microsphere-based systems, providing controlled release delivery, can obviate the need for repeat immunizations. Here, we review the function of sustained and pulsatile release of biodegradable polymeric microspheres in parenteral and mucosal single-dose vaccine administration. We also review the active-targeting function of polymeric particles. With their shield and co-delivery functions, polymeric particles are applied to develop single-dose and mucosally administered vaccines as well as to improve subunit vaccines. Because polymeric particles are easily surface-modified, they have been recently used in vaccine development for cancers and many infectious diseases without effective vaccines (e.g., human immunodeficiency virus infection). These polymeric particle functions yield important vaccine carriers and multiple benefits.
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