外泌体糖基化在疾病诊断及治疗中的应用

外泌体由脂质双分子层构成,内含多种生物分子,如蛋白质、核酸、糖类等,具有调节生命活动的作用,其蛋白质组分也可反映分泌细胞状态。糖基化是一种常见的蛋白质翻译后修饰形式,糖基化蛋白对于维持细胞稳态、细胞间互作等生理功能具有重要作用。近年来,有关于外泌体的研究大多关注外泌体核酸成分如miRNA、mRNA、lncRNA等的功能。外泌体膜蛋白也含有丰富的糖链,且具有重要的病理生理意义。本文着重介绍外泌体糖基化的结构、研究方法、在肿瘤等疾病中的分子功能以及在疾病诊断、治疗中的临床应用和前景。外泌体糖基化研究将随着技术的革新不断深入,有望成为多种疾病临床诊疗的重要手段。     

间充质干细胞来源外泌体在骨关节炎治疗中的作用

骨关节炎(OA)是最常见的慢性退行性骨关节疾病,目前对骨关节炎的治疗还没有特效疗法。间充质干细胞(MSC)对软骨修复有较好的疗效,间充质干细胞来源外泌体可能在这一治疗过程中发挥重要作用。外泌体是细胞间的通讯载体,能在细胞间传递生物活性脂质、核酸以及蛋白质等生物活性分子对骨关节炎产生一定影响。本文就探讨间充质干细胞来源的外泌体治疗骨关节炎过程中的作用机制与可行性做出综述。     

肠道菌群与外泌体及其协同作用对骨稳态影响的研究进展

骨稳态是基于成骨细胞与破骨细胞代谢的动态平衡状态,对骨质疏松症、骨关节炎及股骨头坏死等骨科代谢性疾病的进程至关重要。随着细胞生物分子工程的发展,肠道菌群或外泌体的研究已成为预防或治疗骨代谢相关性疾病的热点,在免疫调节、炎症反应、细胞凋亡、骨代谢及内环境稳态方面的研究颇多。目前在肠道菌群和外泌体协同作用对疾病的调控方面的研究较少,以及对于骨代谢相关性疾病机制的探索方面更是较为有限。笔者通过查阅相关文献,认为肠道菌群与外泌体存在相关性,并且此二者在骨科疾病的治疗方面可能具有很高的研究价值。因此,该文就肠道菌群、外泌体及其协同作用对骨稳态影响的最新研究进展作一综述,以期为临床治疗骨相关性疾病提供新的思路与依据。     

干细胞外泌体在衰老和衰老相关疾病中的作用

随着人口老龄化加剧，衰老及其衰老相关疾病已成为影响生活质量的关键问题。近年来，研究发现干细胞具有抑制炎症、调节免疫反应、预防细胞凋亡、替换和促进受损部位修复等功能。但证据表明，干细胞治疗的效果主要来自干细胞分泌的外泌体。外泌体是由内吞膜衍生而来的纳米级囊泡，包含脂质、蛋白质、核酸和代谢产物等活性物质，是细胞与细胞间通讯的主要参与者。外泌体可以将生物活性物质转移至靶细胞，从而引起靶细胞的表型改变，进而调节器官的修复和再生。表型改变包括防止受体细胞凋亡、诱导靶细胞增殖、刺激免疫调节反应、减小靶细胞氧化应激以及增强氧供应。本文简述了外泌体的生物发生、分泌以及信号传导过程，并重点讨论了在基础研究和临床应用中，不同干细胞来源的外泌体对皮肤衰老和衰老相关疾病(例如心血管疾病、骨关节炎、骨质疏松、阿尔兹海默症)的影响。尽管干细胞外泌体的临床应用仍然存在问题，但它从基础研究到临床应用的前景仍然值得探索，这对于延缓衰老和治疗衰老相关疾病具有重要意义。     

外泌体源性环状RNA在肺癌病理进程及诊疗中的研究进展

外泌体是具有细胞间信号传递生物学功能的一种脂质双分子层囊泡,其内包含RNA、DNA、蛋白质等生物分子,近年来其在疾病发生发展、早期诊断和治疗等方面的作用被广泛研究。环状RNA (circular RNA, circRNA)是一类可以存在于外泌体中的单链闭合环状RNA。越来越多的研究表明外泌体源性circRNA与肺癌的发生发展密切相关,为了更好地了解外泌体源性circRNA在肺癌病理进程中的作用,本文重点讲述了外泌体源性circRNA在肺癌增殖、侵袭与转移、免疫逃逸和耐药中的作用,以及其在肺癌诊断、预后评估及治疗方面的研究进展。     

基于AFM的活体状态外泌体纳米结构及机械特性研究

外泌体在细胞生理病理活动过程中起着重要的调控作用,研究外泌体的行为特性对于揭示生命活动及疾病发生发展的内在机理具有重要的基础意义.然而由于缺乏合适的观测手段及方法,目前对于活体状态下外泌体结构及特性的认知仍然很不足.原子力显微镜(AFM)的发明为研究溶液环境下天然状态生物样本提供了强大的技术工具,已成为生物学重要研究手...     

外泌体在肾病诊疗中的作用

随着靶向治疗技术的发展,外泌体逐渐成为疾病诊疗的重要靶点。多种细胞均可释放外泌体,它们是具有运载物质和传输信号功能的膜性囊泡,是几乎所有细胞胞间的交流媒介。外泌体广泛存在于血液、尿液等体液中,与肾脏的生理病理等方面关系密切。本综述旨在总结外泌体在肾病诊断和治疗的作用和进展,并提出将来外泌体研究、应用和发展的前景。     

神经系统中一种新型的潜在治疗工具——外泌体

外泌体(exosomes)是一种由细胞分泌到胞外空间的纳米囊泡(nanovesicles),在神经系统中参与许多生理病理过程。大量研究表明,在神经系统中,外泌体可以作为细胞通讯的信使,参与复杂的细胞间信息交流。同时,外泌体也可作为诊断疾病的生物标志物及小分子物质传递载体,在治疗神经系统疾病中发挥着至关重要的作用。因此,exosomes有望成为治疗神经系统疾病的重要工具。该综述首先阐述了外泌体的基本特性,包括合成、存储、分离等;其次,讨论了间充质干细胞(mesenchymal stem cells,MSCs)分泌的外泌体在神经退行性疾病的诊断和治疗中的作用;最后,讨论了外泌体作为治疗神经系统疾病的新型工具将面临的挑战。该综述阐明了外泌体这一快速进展领域及其在神经系统疾病中的作用,特别是其治疗应用的最新进展。     

脂肪源性外泌体在动脉粥样硬化病理进展中的作用

动脉粥样硬化是一种病因复杂的血管壁慢性炎症性疾病,近年来其发病率持续增高,肥胖和糖尿病是其公认的危险因素。脂肪组织作为机体内重要的代谢器官,同时亦具有强大的内分泌功能。在肥胖和糖尿病情况下,脂肪组织来源的多种细胞因子及外泌体介导了器官、细胞间的信息交流,参与多种疾病的发生和发展。外泌体作为细胞间重要的通讯媒介,调控多种心血管疾病病理进程,与动脉粥样硬化密切相关。本文围绕动脉粥样硬化病理进程中的内皮功能障碍、炎症反应、脂质代谢紊乱和胰岛素抵抗四个重要的病变过程,就脂肪源性外泌体的作用机制展开综述,以期为该疾病的研究和诊疗提供参考。     

神经干细胞外泌体—神经疾病治疗的新途径

外泌体(exosomes)几乎由所有类型的细胞释放,不同细胞来源的外泌体携带不同的蛋白质、核酸和脂质,参与细胞间的信息交流。最近的研究表明,神经干细胞(neural stem cells,NSCs)分泌的外泌体可参与神经性疾病生理和病理的变化过程,并发挥其潜在的神经调节和修复功能。因此,NSCs分泌的外泌体可以起到治疗神经系统疾病的作用。该文阐述了外泌体的生物合成,NSCs分泌的外泌体的特性、功能及其治疗神经系统疾病的研究进展;讨论了外泌体在神经系统疾病治疗方面的应用潜力和面临的挑战。     

Antibiotics in the treatment of wounds in the victims of the earthquake in the Armenian SSR

Purulent wounds in 88 victims of the Armenian earthquake with the syndrome of long-term squeezing were examined microbiologically and the experience with using antimicrobial drugs for their treatment was analyzed. In all the cases microbial associations were detected, coliform and nonfermenting gram-negative bacilli, enterococci, anaerobes and yeast-like fungi being isolated from 80, 20, 15 and 25 per cent of the patients respectively. 130 bacterial strains were studied in detail. 80 to 100 per cent of the bacterial isolates were resistant to the antibiotics routinely used in surgical practice, i.e. benzylpenicillin, tetracycline, levomycetin, kanamycin, cephalothin and cefazolin and highly sensitive to new antimicrobial drugs belonging to ureidopenicillins (mezlocillin), quinolones (ciprofloxacin) and cephalosporins of the 3rd generation (cefoperazone and ceftazidime). Retrospective estimation of the antibiotic therapy revealed its inadequacy in 55.7 per cent of the patients for the most part because of the isolates resistance. The 19 variants of the antibiotic use prescribed by the physicians mainly included penicillins, aminoglycosides and their combinations (in 67.2 per cent of the cases). The use of the highly efficient drugs of the groups of ureidopenicillins and quinolones was extremely rare which was likely due to lacking of information on the drugs.     

Histogenesis of the taste buds of the vallate papilla in the in the rat in the postnatal stages of development

The developing taste buds of vallate papillae were studied with electron microscope in rats during the first 7 days after birth. Two types of cells--light and dark--are identified in the taste buds of a one day old animal. The apical parts of dark cells are characterized by numerous dark granules. A distinguishing feature of light cells is the presence of synaptic contacts with afferent intragemmal nerves. On the 4th day of development on the top of the apical parts of the cell, a microvillar apparatus is seen to form, which does not yet communicate with the oral cavity. On the 7th day, basal cells appear in the taste buds. Some of these cells are seen mitotically dividing. The differentiated microvillar apparatus now communicates with oral cavity. The structure of the taste buds is getting similar to that in the adults. The structural and functional peculiarities of the developing taste buds are discussed in association with the period of ontogenesis under consideration.     

Changes in the size of the nucleoli of the Purkinje cells in the canine cerebellum in the postresuscitation period

The changes in the size of Purkinje cell (PC) nucleolus in the lateral and medial cerebellum zones were studied in dogs with different degree of neurologic status recovery after clinical death of various etiology and duration. PC always possess one nucleolus in the control and experimental groups. In the case of complete neurologic status recovery of animals the area of PC nucleolus increases in both zones studied, irrespective of the cause of clinical death. In the case of neurologic disorders the increase in PC nucleolus area is clearly expressed only in the medial zone of the cerebellum, being insignificant in the lateral zone. It is suggested that adaptive characteristics of PC are distinct in the two compared zones, which leads to greater PC vulnerability in the lateral zone during deep hypoxia.     

Frequency of the stages in the cycle of the seminiferous epithelium in the rat

This study determined the optimum number of tubules to be counted per testis cross section, and the number of animals per treatment group, when changes in stage frequencies in the cycle of the seminiferous epithelium are criteria for assessing effects of treatment on spermatogenesis. A data base of 9,672 observed and staged tubules was collected from testicular cross sections of 15 Sprague-Dawley rats. A significant variation between animals was found for the frequencies of Stages I, II, IV, VI, VIII, and XIII. Computer simulation was used to randomly select different combinations of animal and tubule numbers from the observed data. Stage frequency means from each simulation experiment were compared statistically to observed mean frequencies. A model that used data from all 14 stages was analyzed. The following conclusions were made: a) a minimum of 200 tubule cross sections/testis is recommended for estimating stage frequencies; b) for a fixed number of tubules scored, the number of animals sampled is more important than the number of tubules per animal in reducing variance; c) to detect a difference of 2 standard deviations from the mean with a 2% error rate and examining 200 tubules/testis, at least 12 animals must be used per group when assessing all 14 stages; d) when individual stages are examined using 10 animals per group, only Stage VII has 80% or greater power of test (alpha = 0.05) to detect a frequency difference; e) pooling stages into 3-4 groups is recommended to improve the power of detecting a treatment difference.     

Self-organization in the determination of the size of the axial structures in the embryogenesis of the clawed toad

Experiments were performed using X. laevis embryos during gastrulation and neurulation (stages 10, 11 1/2, 12 1/2, 13 1/2, 15 and 18). Part of presumptive epidermis and lateral plate mesoderm was removed, and embryos raised until stage 25. The size of axial structures (notochord, somite mesoderm, central nervous system) was determined using serial histological sections and compared with that of control embryos. In experimental embryos, the size of axial structures was decreased. Until a specific stage of development, close correlation was found between the volume of embryonic compartment corresponding to a particular, structure and the volume of presumptive epidermis and lateral plate mesoderm. This stage is individual for each axial organ: middle gastrula (stage 11 1/2) for notochord, late gastrula (stage 12 1/2) for somite mesoderm, and late neurula (stage 18) for central nervous system. This data suggest that differentiation pattern of ecto-mesodermal rudiment is subject to regulation during gastrulation-neurulation, and subdivision of ectoderm and mesoderm into axial and non-axial tissues is a self-organizing process.     

Role of the mediodorsal nucleus of the thalamus in the function of generalization in the cat

In chronic experiments on cats contribution of the thalamic mediodorsal nucleus to the organization of the processes of generalization and abstraction was studied by means of alternation method. Electrolytic ablation of the nucleus retarded the learning and impeded the initial stages of formation of the generalization function. Mechanisms of thalamic dementia are discussed.