线粒体DNA靶向治疗

线粒体(mitochondrion)是真核生物细胞中的一种非常重要的细胞器,含有独立于细胞核染色体外的遗传物质,通过氧化磷酸化产生ATP,是细胞的能量工厂,与细胞分化、信号转导、代谢稳态等过程密切联系。线粒体功能的紊乱与癌症、神经退行性疾病、糖尿病等许多疾病的发生、发展及治疗息息相关。线粒体在细胞命运中扮演的关键角色,使对线粒体这一特殊细胞器的探索成为生命科学研究热点之一。人线粒体DNA(mitochondrial DNA, mtDNA)是一相对保守且仅16 kb的环状双链DNA分子,只含37个基因,但这些基因都是维持线粒体功能稳定必不可少的部分。随着对线粒体功能认识的不断深入,研究人员发现mtDNA突变,会导致活性氧自由基过量产生,从而引起细胞衰老,甚至引发诸多疾病,例如遗传性视神经病变、线粒体脑肌病伴高乳酸血症和卒中样发作综合征等。但是,目前针对这些线粒体基因疾病尚无非常有效的治疗手段。为了进一步了解这一关键细胞器,研究人员开发了一些有效的方法来突破线粒体的复杂屏障。本文将重点介绍并讨论近几年靶向mtDNA的研究进展,主要从药物修饰、材料递送、基因编辑等方面进行了总结,希望能为推动线粒体的研究提供一些新的思路。     

综述与专论：纳米药物递送系统：胰腺癌靶向策略的新选择

胰腺导管腺癌（PDAC）是一类进展迅速、早期诊断困难的恶性消化系统实体肿瘤,多数患者就诊时已失去根治性手术切除机会。PDAC组织中的多种细胞成分和非细胞成分组成复杂的调控网络,共同塑造了代谢异常的肿瘤微环境,导致临床化疗和免疫治疗等效果受限。纳米技术的发展为PDAC的高效药物递送和精准靶向治疗提供了新思路。本文从靶向肿瘤细胞与肿瘤微环境两个方面,综述了近年来基于纳米药物递送系统的PDAC治疗策略,并总结了本团队在相关领域的研究进展,为胰腺癌的治疗提供参考。     

纳米递送系统线粒体靶向策略在肿瘤诊疗中的应用

肿瘤是危害人类健康的重大疾病之一。目前用于肿瘤治疗的方法有手术治疗、化学药物治疗、放射治疗等。然而,传统的治疗方法存在治疗效果不佳、易引发多药耐药、毒副作用大等缺点,仍需进一步探索新的肿瘤治疗靶点和策略。线粒体作为细胞的能量转换器,被认为是肿瘤、心血管和神经性疾病新药设计的最重要靶点之一。纳米药物递送载体具有易被主动靶向基团修饰的特点,可实现细胞乃至细胞器的精准靶向给药。本文从抑制肿瘤细胞增殖、促进肿瘤细胞凋亡、抑制肿瘤复发与转移、诱导细胞自噬等方面综述了线粒体靶向纳米载体在肿瘤诊疗中的应用。     

糖类修饰的纳米递送系统

癌症的高病发率和高死亡率已经引起了人们广泛的重视.传统治疗癌症的药物分子存在水溶性较差、无靶向性、生物安全性低等问题.纳米递送系统如脂质体、聚合物纳米粒子和共聚物胶束解决了传统癌症治疗过程中药物水溶性较差的问题.但大多数纳米递送系统不具备靶向性和生物相容性,且药物包封率不高.糖类作为具有较好的靶向特异性识别能力、安全性...     

药物递送载体靶向治疗中枢神经系统淋巴瘤的研究进展

中枢神经系统淋巴瘤(central nervous system lymphoma,CNSL)少见且治疗困难.目前主流方案多为采用大剂量可通过血脑屏障(blood brain barrier,BBB)的化疗药物静脉给药或治疗有效的药物鞘内注射给药治疗,然而效果欠佳.许多外周疗效佳的化疗药物难以跨越BBB,或进入中枢神经...     

药物靶向递送策略在肿瘤免疫治疗中的应用

本文通过回顾近年来药物靶向递送策略在肿瘤免疫治疗中的有关文献,简述其优势及应用,具体分为以下三个方面进行阐述:主动性靶向递送策略、被动性靶向递送策略及内响应性和外响应性的物理化学靶向递送策略,并提出了目前的不足和未来的展望。分析表明,药物靶向递送策略在肿瘤的免疫治疗中有着广阔的应用前景,为探索更好的肿瘤免疫治疗策略提供了理论基础。     

PhaP介导EGFR靶向多肽修饰的肿瘤靶向PHBHHx纳米药物递送载体的构建

聚羟基脂肪酸(PHA)颗粒表面结合蛋白Pha P具有与疏水性高分子材料表面紧密结合的能力,本研究将EGFR靶向多肽(ETP)与PhaP进行融合表达,构建了ETP-PhaP融合蛋白表达的重组工程菌Escherichia coli BL21(DE3)(pPI-ETP-P)。经对工程菌株的诱导表达及ETP-PhaP融合蛋白的纯化后,通过PhaP蛋白介导能够有效地将ETP-PhaP融合蛋白修饰于3-羟基丁酸-3-羟基己酸共聚酯(PHBHHx)纳米微球表面,构建成为具有EGFR靶向作用的药物递送载体。分别检测宫颈癌细胞系SiHa(EGFR高表达)和CaSKi(EGFR低表达)对ETP-PhaP修饰的PHBHHx纳米药物载体和未经修饰的纳米药物载体的吞噬情况。结果显示,纯化的ETP-PhaP融合蛋白能够很好地吸附于PHBHHx颗粒的表面,经ETP-PhaP融合蛋白修饰的PHBHHx纳米药物载体对EGFR高表达的宫颈癌Si Ha细胞的靶向效果强于EGFR低表达的CaSKi细胞系。这一结果表明了PhaP介导的PHBHHx纳米微球表面EGFR靶向多肽修饰具有简便、高效的优势,为疏水性纳米药物载体表面功能多肽修饰提供了一种新策略。     

纳米药物递送系统在缺血性脑卒中治疗中的研究进展

缺血性脑卒中(ischemic stroke)是全球人口死亡和残疾的主要原因,其发病过程复杂且治疗方法十分有限。近年来,纳米药物递送系统(nano-drug delivery systems, NDDS)在治疗脑部疾病方面显示出巨大的潜力。纳米载体可以携带药物通过血脑屏障,并通过靶向配体的修饰将药物递送到特定的细胞。本文主要综述了缺血性脑卒中的发病机制以及当前治疗方法的局限性,重点介绍了纳米药物递送系统治疗缺血性脑卒中的进展。最后提出该领域的挑战和未来方向,以推动纳米药物递送系统在缺血性脑卒中治疗中的发展。     

细胞/细菌驱动的药物递送系统研究进展

细胞/细菌驱动的药物传递系统是一种有前景的药物递送策略. 该策略将具有不同优异特性的活细胞/细菌与药物有机结合,能够有效克服传统纳米药物生物利用率低、靶向性能弱、组织穿透性不强等缺陷. 得益于对目标病灶特异响应,这类药物递送系统不仅能够实现药物高效的主动靶向递送,还可以降低对正常组织的毒副作用,目前已成功运用于药物呈递,在疾病诊断和治疗领域展示了广阔的应用前景. 本文初步探讨了细胞/细菌驱动的药物递送系统的研究进展,并对其未来研究进行展望.     

纳米药物递送系统在前列腺癌治疗中的应用

前列腺癌（PCa）是全球最常见的男性泌尿生殖系统恶性肿瘤。手术、内分泌治疗、放疗和化疗是PCa的主要临床治疗选择。纳米药物递送系统具有良好的可控释放特性和较好的肿瘤靶向能力,并可通过增强的渗透性和保留（EPR）效应被动靶向肿瘤。通过精巧的设计组装和外表修饰赋予纳米递药系统与众不同的肿瘤治疗效果。本文介绍用于PCa治疗的先进纳米药物递送系统以及未来发展。     

Bioinspired Hollow Mesoporous Silica Nanoparticles Coating on Titanium Alloy with Hierarchical Structure for Modulating Cellular Functions

3D-printed Porous Titanium Alloy Implants(pTi),owing to their biologically inertness and relatively smooth surface morphology,adversely affect the biological functions of surrounding cells.To address the challenges,constructing a bio-inspired interface that mimics the hierarchical structure of bone tissue can enhance the cellular functions of cells.In this context,Hollow Mesoporous Silica Nanoparticles(HMSNs),renowned for their unique physicochemical properties and superior biocompatibility,offer a promising direction for this research.In this research,the initially synthesized HMSNs were used to construct a\"hollow-mesoporous-macroporous\"hierarchical bioinspired coating on the pTi surface through the Layer-by-Layer technique.Simultaneously,diverse morphologies of coatings were established by adjusting the depo-sition strategy of PDDA/HMSNs on the pTi surface(pTi-HMSN-2,pTi-HMSN-4,pTi-HMSN-6).A range of techniques were employed to investigate the physicochemical properties and regulation of cellular biological functions of the diverse HMSN coating strategies.Notably,the pTi-HMSN-4 and pTi-HMSN-6 groups exhibited the uniform coatings,leading to a substantial enhancement in surface roughness and hydrophilicity.Meantime,the coating constructed strategy of pTi-HMSN-4 possessed commendable stability.Based on the aforementioned findings,both pTi-HMSN-4 and pTi-HMSN-6 facilitated the adhesion,spreading,and pseudopodia extension of BMSCs,which led to a notable upsurge in the expres-sion levels of vinculin protein in BMSCs.Comprehensive analysis indicates that the coating,when PDDA/HMSNs are deposited four times,possesses favorable overall performance.The research will provide a solid theoretical basis for the translation of HMSN bioinspired coatings for orthopedic implants.     

Graft copolymers of xyloglucan and methyl methacrylate

Xyloglucan, a water-soluble food grade polysaccharide, was reported as a substrate for graft copolymerization of methyl methacrylate (MMA). Grafting PMMA (polymethyl methacrylate) with xyloglucan (XG) makes a new material with improved thermal stability and shelf life without affecting its hydrophilicity. XG was isolated from tamarind seed mucilage by aqueous extraction. Grafting of MMA was initiated by ceric ion in aqueous medium under N₂ atmosphere and the progress of the reaction was monitored gravimetrically by varying different reaction parameters. Grafting of MMA onto XG was confirmed by FTIR spectroscopy, NMR spectroscopy, differential scanning calorimetric (DSC) studies, thermal gravimetric analysis (TGA) studies and scanning electron micrographs (SEMs). This material might find potential to be used in drug delivery systems.     

细胞分离用SiO2纳米微粒的制备--制备条件对SiO2纳米微粒性能的影响

利用SiO2纳米微粒实现细胞分离技术的关键就是如何制备粒径为15～20mm,纯度高,比表面积大,吸附性好,结构为无定型的SiO2纳米微粒．以硅酸钠、硫酸为原料,采用一步法直接制备得到细胞分离用SiO2纳米微粒,探讨了制备条件对SiO2纳米微粒性能的影响,确立了最优化的制备条件．     

Label electrochemical immunosensor for prostate-specific antigen based on graphene and silver hybridized mesoporous silica

Prostate-specific antigen (PSA), as the specificity of prostate cancer markers, has been widely used in prostate cancer diagnosis and screening. In this study, we fabricated an electrochemical immunosensor for PSA detection using the amino-functionalized graphene sheet–ferrocenecarboxaldehyde composite materials (NH₂-GS@FCA) and silver hybridized mesoporous silica nanoparticles (Ag@NH₂-MCM48). Under optimal conditions, the fabricated immunosensor showed a wide linear range with PSA concentration (0.01–10.0 ng·ml⁻¹). Low detection limit (2 pg·ml⁻¹) proved the high sensitivity. In addition, the immunosensor possessed good stability and reproducibility. Moreover, the application to PSA analysis in serum samples yielded satisfactory results.     

A multi-amplification aptasensor for highly sensitive detection of thrombin based on high-quality hollow CoPt nanoparticles decorated graphene

In this work, we have successfully demonstrated a facile strategy to incorporate high-quality hollow CoPt bimetal alloy nanoparticles (HCoPt) onto reduced graphene oxide sheet (HCoPt-RGs). An advanced sandwich-type electrochemical aptasensor for thrombin was proposed by using the HCoPt-RGs conjugates as secondary label. The formed conjugates provided large surface area for loading plentiful redox probe thionine (Thi), horseradish peroxidase (HRP) and secondary aptamer (Apt II) with good stability and friendly biocompatibility, indicating their superior properties in electroactive mediator enrichment and biomolecule immobilization. Furthermore, activated by glutaraldehyde (GA), the chitosan-hollow CoPt alloy nanoparticle (CS-HCoPt) film can greatly facilitate the capture of primary aptamer (Apt I) and dramatically reduce the nonspecific binding. Excellent sensitivity was obtained by detecting the conspicuously enhanced electrochemical signal of Thi, which was amplified by HCoPt alloy nanoparticles and HRP toward the catalytic reduction of H₂O₂. The aptasensor displayed excellent performance for thrombin with a wide linearity in the range from 1.0 × 10⁻¹² to 5.0 × 10⁻⁸ M and a relatively low detection limit of 3.4 × 10⁻¹³ M. Moreover, the resulted aptasensor also exhibited good specificity, acceptable reproducibility and stability, indicating that the present strategy could pave a promising way for the wide application of graphene in clinical research.     

Effects of a nanoparticulate silica substrate on cell attachment of Candida albicans

AIMS: To investigate the influence of silica nanoparticles on the attachment and growth of Candida albicans cells. METHODS AND RESULTS: Spherical silica nanoparticles with diameters of 4, 7, 14 or 21 nm were attached to tissue culture polystyrene by a polycationic binding layer using a simple deposition procedure. The modified surfaces were shown to reduce the attachment and growth of C. albicans cells by a range of different measurements including microscopy, staining cells and measuring the amount of dye taken up and total cell activity measured using a dye reduction assay. For those cells that did attach and grow, the nanoparticle-coated surface inhibited the yeast to hyphal transition that is induced in the presence of serum. The greatest effect was observed for 7 and 14 nm diameter silica particles and we propose that the mechanism for these effects are related to either the topography of the surface or the slow dissolution of the bound silica. CONCLUSIONS: The attachment and growth of C. albicans is reduced by surface modification with silica nanoparticles. SIGNIFICANCE AND IMPACT OF THE STUDY: The modification of surfaces by nanoparticulate coatings is a simple process that may have applications in reducing the prevalence of Candida sp. cells on medical devices thus, limiting the incidence of this pathogenic yeast in clinical environments.     

Generation and study of a relatively large amorphous silica surface in the liquid phase

Through the classical and ab-initio molecular dynamics computer simulations, the aim of this study was to generate and analyse a surface-type structure in the liquid phase at a temperature of 3400?K. First, a crystalline structure was used (β-cristobalite) with 216 SiO₂ molecules (648 atoms) and it was melted. Next, the resulting structure was properly cut, with a total of 546 particles remaining, and this system was put into a geometric arrangement denominated ‘sandwich’, where it was equilibrated. The prior processes were implemented through the classical molecular dynamics computer simulations using the effective classical potential of Feuston [B. P. Feuston and S. H. Garofalini, J. Chem. Phys. 89, 5818 (1988)]. Finally, the electronic charge distribution and topological and bonding defects were analysed in the first five superior layers of this system. This latter was carried out through the ab-initio molecular dynamics computer simulations, where the pseudopotentials of N. Trouiller and J. L. Martins [N. Trouiller, J. L. Martins, Phys. Rev. B 43, 1993 (1991)] were used. The results show different aspects between them, the interaction between the bonding and topological defects, and the existence of two-membered rings, nonbridging oxygens (NBOs) and three-coordinated silicon at the outermost surface.