基于微流控芯片的高糖对模式生物线虫寿命影响及白藜芦醇苷保护性作用考察

线虫是一种经典的模式生物,在分子和基因水平上与人类具有高度同源性,目前已被广泛应用于生命科学领域。本文以微流控芯片为平台,以模式生物秀丽隐杆线虫为研究对象,在单个线虫操作的水平上探讨高糖对线虫寿命和氧化应激的影响,同时考察了白藜芦醇苷对高糖引起的线虫寿命及应激响应变化的保护性作用。结果表明,高糖会缩短线虫寿命并增强线虫的氧化应激蛋白GST-4表达;而白藜芦醇苷会显著减弱高糖诱导的线虫应激反应并延长线虫寿命,表明白藜芦醇苷对高糖诱发的线虫应激反应具有保护性作用。本文所建立的单个线虫操控的微流控芯片可以为动物水平上治疗糖尿病的相关药物评价提供一种新的潜在平台。     

微流控芯片用于模式生物衰老研究

<正>中科院大连化物所秦建华团队近期在以微流控芯片为平台的模式生物秀丽隐杆线虫抗衰老研究方面取得新进展。相关成果以封面文章形式发表于《整合生物学》杂志。白藜芦醇苷是一种存在于天然植物中的功效成分,具有保护肝脏、抑制血小板聚集、抗菌、抗病毒、降血脂及抗脂质过氧化等多种药理作用。不过,科学家对其抗衰老作用和分子机制等尚不清楚。为此,科研人员以经典的模式生物秀丽隐杆线虫为衰老模型,首次建立了集单线虫进样、长期培养、运动监测、固定及成像多功能的集成化微流控药物评价平台,研究考察了天然提取物白藜芦醇苷     

微流控芯片的研究及产业化

以大连研究团队的近期工作为基础,结合2015年末召开的“深圳-大连微流控芯片及其产业化战略研讨会”内容,扼要阐述作者对近期微流控芯片的研究及产业化的基本看法.鉴于微流控芯片研究的主流已从平台构建和方法发展转为不同领域的广泛应用,本文重点介绍了微流控芯片在现代生物化学分析、即时诊断、材料筛选-材料合成以及组织-器官仿生等4个应用领域的研究趋势,讨论了3D打印技术的崛起对微流控芯片的影响和挑战,阐述了微流控芯片作为当代极为重要的新兴科学技术平台和国家层面产业转型的潜在战略领域,在全球范围内产业化的发展势头.全文引用文献69篇.     

磁控微流控芯片的研究现状及应用

微流控芯片作为一种现代分析方法,近年来得到迅速发展。而磁控微流控芯片是在微流控芯片中引入磁场调控,通过引入磁场丰富了微流控芯片的操控手段,同时结合了磁性材料的优势,使之成为微流控芯片研究的重要组成部分之一。本文重点介绍磁控微流控芯片的研究现状及应用。     

微流控系统在生化分析领域的新应用

微流控芯片是近年来新兴的研究领域,它由微米级别的微通道及辅助器件构成,并且有着低试剂消耗量、响应时间短、高精度、高灵敏度、高集成度和独特的微观物理现象等特性.微流控芯片的独特优势为生物样品的处理与分析、生物模拟、药物传递和多组分分析等领域提供了前所未有的机会.为获得理想、完善的微流控平台,还需进一步挖掘微流控芯片的潜在...     

微流控芯片细胞实验室

以作者所在课题组近年开展的研究工作为基础,阐述了微流控芯片细胞实验室的平台特征,并从细胞个体、群体和多细胞生命体研究等三个方面概述微流控芯片细胞实验室的应用对象特征,显示其在生物医学领域的应用前景。     

生命分析微流控芯片的多尺度应用:从分子水平到个体水平

微流控芯片技术是多学科、多领域交叉的新兴分析技术,具有微型化、集成化、高通量、低消耗、高灵敏、分析速度快等特点。如今,微流控芯片技术已发展成为自然科学研究中不可或缺的技术平台,展现出巨大的优势,尤其在生命科学研究中得到了广泛应用。该文概述了近年来微流控芯片技术在分子水平、细胞水平、组织器官水平和生物个体水平等多个尺度上的应用,并对其发展前景进行了展望。     

微流控芯片分选临床样品中循环肿瘤细胞的研究进展

癌症作为常见病正严重威胁着我国乃至全球居民的健康。循环肿瘤细胞(CTCs)是一类由癌变部位释放并进入血液中的癌细胞,其在癌症的早期诊断、个体化及肿瘤转移机制研究等方面的作用正逐渐被发现和认可,但由于血液中的CTCs含量极少,对其分选极具挑战。微流控芯片作为一种微型化、高通量、集成化平台,在CTCs研究中彰显了独特的优势,相关报道也越来越多。随着研究的深入,微流控芯片技术不再局限于基于模型样品的方法学开发,而是更注重于能否用于临床实际样品中CTCs的检测,但目前未见该角度的综述报道。为此,文章综述了近年来用于临床实际样品CTCs分析的微流控芯片分选技术,并探讨了微流控芯片用于CTCs分选的发展趋势。     

微流控纸芯片的加工技术及其应用

微流控纸芯片是一种新兴的微流控分析技术平台,具有成本低、加工简易、使用和携带方便等优点,在临床诊断、食品质量控制和环境监测等应用领域具有很大的应用前景,近年来,引起广大科学工作者极大的兴趣。本文着重介绍目前文献相继报道的各种纸芯片加工技术,包括紫外光刻、蜡印、等离子体处理、喷墨打印、喷墨溶剂刻蚀、绘图、柔印和激光光刻等技术。此外,还介绍了微流控纸芯片分析中的检测方法及其应用。     

纸芯片微流控技术的发展及应用

纸芯片微流控技术是一种新型微流控技术。相比于以玻璃、石英、高聚物等为基底的传统微流控芯片,纸芯片具有成本低、易操作、可携带、耗样量小等优点。该文介绍了纸芯片的发展及常用的制作方法,并举例说明了光度法、荧光法、化学发光及电化学发光法和电化学法在纸芯片检测中的应用;归纳了纸芯片技术在临床诊断、环境监控以及食品安全分析等方面的应用;最后对纸芯片微流控的应用前景进行了展望。     

Chemistry and the worm: Caenorhabditis elegans as a platform for integrating chemical and biological research

This Review discusses the potential usefulness of the worm Caenorhabditis elegans as a model organism for chemists interested in studying living systems. C. elegans, a 1 mm long roundworm, is a popular model organism in almost all areas of modern biology. The worm has several features that make it attractive for biology: it is small (<1000 cells), transparent, and genetically tractable. Despite its simplicity, the worm exhibits complex phenotypes associated with multicellularity: the worm has differentiated cells and organs, it ages and has a well-defined lifespan, and it is capable of learning and remembering. This Review argues that the balance between simplicity and complexity in the worm will make it a useful tool in determining the relationship between molecular-scale phenomena and organism-level phenomena, such as aging, behavior, cognition, and disease. Following an introduction to worm biology, the Review provides examples of current research with C. elegans that is chemically relevant. It also describes tools-biological, chemical, and physical-that are available to researchers studying the worm.     

A novel microfluidic capture and monitoring method for assessing physiological damage of C. elegans under microgravity

Spatial microgravity is a significant factor affecting and causing physiological changes of organisms in space environment. On‐site assessment of the damage associated to microgravity is very important for future long‐term space exploration of mankind. In this paper, a new microfluidic device for analyzing the damage of microgravity on Caenorhabditis elegans (C. elegans) has been developed. This device is mainly composed of a microfluidic chip, a dual imaging module, and an imaging acquisition and processing module, which are integrated into a compact system. The microfluidic chip is designed as a platform for monitoring C. elegans, which is captured in an imaging region through a suction structure in the microfluidic chip. A dual imaging module is designed to obtain the images of bright field and fluorescence of C. elegans. The behaviors of C. elegans are analyzed based on the dual‐mode imaging of bright field and fluorescence to assess the degree of damage due to microgravity. A comparative study using a commercial microscope is also conducted to demonstrate the unique advantage of the developed system under the simulated microgravity. The results show that the developed system can evaluate the damage of C. elegans under microgravity accurately and conveniently. Furthermore, this device has compact size and weight, easy operation, and low‐cost, which could be highly advantageous for on‐site evaluation of the damage to microorganisms under microgravity in a space station.     

A microfluidic device for whole-animal drug screening using electrophysiological measures in the nematode C. elegans

This paper describes the fabrication and use of a microfluidic device for performing whole-animal chemical screens using non-invasive electrophysiological readouts of neuromuscular function in the nematode worm, C. elegans. The device consists of an array of microchannels to which electrodes are attached to form recording modules capable of detecting the electrical activity of the pharynx, a heart-like neuromuscular organ involved in feeding. The array is coupled to a tree-like arrangement of distribution channels that automatically delivers one nematode to each recording module. The same channels are then used to perfuse the recording modules with test solutions while recording the electropharyngeogram (EPG) from each worm with sufficient sensitivity to detect each pharyngeal contraction. The device accurately reported the acute effects of known anthelmintics (anti-nematode drugs) and also correctly distinguished a specific drug-resistant mutant strain of C. elegans from wild type. The approach described here is readily adaptable to parasitic species for the identification of novel anthelmintics. It is also applicable in toxicology and drug discovery programs for human metabolic and degenerative diseases for which C. elegans is used as a model.     

Maze exploration and learning in C. elegans

The soil dwelling nematode, Caenorhabditis (C.) elegans, is a popular model system for studying behavioral plasticity. Noticeably absent from the C. elegans literature, however, are studies evaluating worm behavior in mazes. Here, we report the use of microfluidic mazes to investigate exploration and learning behaviors in wild-type C. elegans, as well as in the dopamine-poor mutant, cat-2. The key research findings include: (1)C. elegans worms are motivated to explore complex spatial environments with or without the presence of food/reward, (2) wild-type worms exhibit a greater tendency to explore relative to mutant worms, (3) both wild-type and mutant worms can learn to make unconditioned responses to food/reward, and (4) wild-type worms are significantly more likely to learn to make conditioned responses linking reward to location than mutant worms. These results introduce microfluidic mazes as a valuable new tool for biological behavioral analysis.     

In vivo Toxicity Evaluation of a Nano-drug Delivery System Using a Caenorhabditis elegansModel System

Drug carrier materials need to possess good biological safety. Presently, most biosafety evaluation studies use rodent animal models, including rats and rabbits. However, the cost of raising these animals is relatively high and the experimental period is long. Caenorhabditis elegans(C. elegans) presents an ideal toxicological evaluation model due to its simple structure, easy cultivation, short life cycle, and evolutionary conservation. In this paper, we used C. elegans to test the biological safety of our pH-responsive carrier system(FFPFF self-assembling into a nanosphere structure, FFPFF Nps), which was designed for anti-tumor drug delivery. Our results showed that exposure to high doses of FFPFF Nps did not have a significant impact on the survival rate, growth, development, movement, and reproduction of C. elegans. The preliminary evaluation of the overall biological model of C. elegans shows that FFPFF Nps has good biological safety and warrants further study.     

Analysis of Caenorhabditis elegans in microfluidic devices

Caenorhabditis elegans (C. elegans) is widely adopted as a model organism for a variety of biological studies including development, genetics and neurobiology. Micro-scale microfluidic technology is capable of handling single or populations of C. elegans in high throughput format and allows for the precise spatial and temporal control of their environment, which is well suited for the study of worms in different aspects. In this review, we highlight the recent advances in microfluidic technology for the analysis of worms ranging from behavioral studies to neurobiology. We believe that microfluidic device can further be applied to study the different aspects of worms, extending from fundamental investigation of behavioral dynamics to more complicated biological processes including neurochemistry and learning behaviors.     

Effectively controlled microfluidic trap for spatiotemporal analysis of the electrotaxis of Caenorhabditis elegans

C. elegans is a popular model organism with a well‐developed neural network. Approximately 60% of the genes in C. elegans have genomic counterparts in humans, including those involved in building neural circuits. Therefore, we can extend the study of human neural network mechanisms to C. elegans which is easy to genetically manipulate. C. elegans shows behavioural responses to various external physical and chemical stimuli. Electrotaxis is one of its distinct behavioural responses, which is defined as movement towards the cathode in an electric field. In this study, we developed an effective microfluidic trap system for analysing electrotaxis in C. elegans. In addition, two mutant strains (unc‐54(s74) and unc‐6(e78)) from wild‐type (N2) worms were screened using the system. Wild‐type (N2) worms and the two mutant strains clearly showed different behavioural responses to the applied electric field, thus enabling the effective screening of the mutant worms from the wild type (N2). This microfluidic system can be utilized as a platform for the study of behavioural responses, and for the sorting and mutant screening of C. elegans.     

Electrical sorting of Caenorhabditis elegans

The nematode (worm) C. elegans is one of the widely studied animal model organisms in biology. It develops through 4 larval stages (L1-L4) in 2 to 3 days before becoming a young adult. Biological assays involving C. elegans frequently require a large number of animals that are appropriately staged and exhibit a similar behaviour. We have developed a new method to synchronize animals that relies on the electrotactic response (electric field-induced motion) of C. elegans to sort them in parallel based on their age, size and phenotype. By using local electric field traps in a microfluidic device, we can efficiently sort worms from a mixed culture in a semi-continuous flow manner (with a minimum throughput of 78 worms per minute per load-run) and obtain synchronized populations of animals. In addition to sorting larvae, our device can also distinguish between young and old adults efficiently. Unlike fluorescent based sorting systems that use active imaging based feedback, this method is passive and automatic and uses the innate behaviour of the worm. Considering that the entire procedure takes only a few minutes to run and is cost-effective, it promises to simplify and accelerate experiments requiring homogeneous cultures of worms as well as to facilitate isolation of mutants that have abnormal electrotaxis. More importantly, our method of isolating and separating worms using locomotion as a defining characteristic promises development of advanced microfluidics-based systems to study the neuronal basis of movement-related defects in worms and facilitate high-throughput chemical screening and drug discovery.     

A microfluidic platform for high-sensitivity, real-time drug screening on C. elegans and parasitic nematodes

This paper describes a new microfluidic platform for screening drugs and their dose response on the locomotion behavior of free living nematodes and parasitic nematodes. The system offers a higher sensitivity drug screening chip which employs a combination of existing and newly developed methods. Real-time observation of the entire drug application process (i.e. the innate pre-exposure locomotion, the transient response during drug exposure and the time-resolved, post-exposure behavior) at a single worm resolution is made possible. The chip enables the monitoring of four nematode parameters (number of worms responsive, number of worms leaving the drug well, average worm velocity and time until unresponsiveness). Each parameter generates an inherently different dose response; allowing for a higher resolution when screening for resistance. We expect this worm chip could be used as a robust cross species, cross drug platform. Existing nematode motility and migration assays do not offer this level of sophistication. The device comprises two principal components: behavioral microchannels to study nematode motility and a drug well for administering the dose and observing drug effects as a function of exposure time. The drug screening experiment can be described by three main steps: (i) 'pre-exposure study'- worms are inserted into the behavioral channels and their locomotion is characterized, (ii) 'dose exposure'- worms are guided from the behavioral microchannels into the drug well and held for a predefined time, during which time their transient response to the dose is characterized and (iii) 'post-exposure study'- worms are guided back into the behavioral microchannels where their locomotion (i.e. their time-resolved response to the dose) is characterized and compared to pre-exposure motility. The direction of nematodes' movement is reliably controlled by the application of an electric field within a defined range. Control experiments (e.g. in the absence of any drug) confirm that the applied electric fields do not affect the worms' motility or viability. We demonstrate the workability of the microfluidic platform on free living Caenorhabditis elegans (wild-type N2 and levamisole resistant ZZ15 lev-8) and parasitic Oesophagotomum dentatum (levamisole-sensitive, SENS and levamisole-resistant, LEVR) using levamisole (a well-studied anthelmintic) as the test drug. The proposed scheme of drug screening on a microfluidic device is expected to significantly improve the resolution, sensitivity and data throughput of in vivo testing, while offering new details on the transient and time-resolved exposure effects of new and existing anthelmintics.