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81.
82.
A half-center oscillator (HCO) is a common circuit building block of central pattern generator networks that produce rhythmic
motor patterns in animals. Here we constructed an efficient relational database table with the resulting characteristics of
the Hill et al.’s (J Comput Neurosci 10:281–302, 2001) HCO simple conductance-based model. The model consists of two reciprocally inhibitory neurons and replicates the electrical
activity of the oscillator interneurons of the leech heartbeat central pattern generator under a variety of experimental conditions.
Our long-range goal is to understand how this basic circuit building block produces functional activity under a variety of
parameter regimes and how different parameter regimes influence stability and modulatability. By using the latest developments
in computer technology, we simulated and stored large amounts of data (on the order of terabytes). We systematically explored
the parameter space of the HCO and corresponding isolated neuron models using a brute-force approach. We varied a set of selected
parameters (maximal conductance of intrinsic and synaptic currents) in all combinations, resulting in about 10 million simulations.
We classified these HCO and isolated neuron model simulations by their activity characteristics into identifiable groups and
quantified their prevalence. By querying the database, we compared the activity characteristics of the identified groups of
our simulated HCO models with those of our simulated isolated neuron models and found that regularly bursting neurons compose
only a small minority of functional HCO models; the vast majority was composed of spiking neurons. 相似文献
83.
Understanding miRNAs' regulatory networks and target genes could facilitate the development of therapies for human diseases such as cancer. Although much useful gene expression profiling data for tumor cell lines is available, microarray data for miRNAs and mRNAs in the human HepG2 cell line have only been compared with that of other cell lines separately. The relationship between miRNAs and mRNAs in integrated expression profiles for HepG2 cells is still unknown. To explore the miRNA–mRNA correlations in hepatocellular carcinoma (HCC) cells, we performed miRNA and mRNA expression profiling in HepG2 cells and normal liver HL-7702 cells at the genome scale using next-generation sequencing technology. We identified 193 miRNAs that are differentially expressed in these two cell lines. Of these, 89 miRNAs were down-regulated in HepG2 cells compared with HL-7702 cells, while 104 miRNAs were up-regulated. We also observed 3035 mRNAs that are significantly dys-regulated in HepG2 cells. We then performed an integrated analysis of the expression data for differentially expressed miRNAs and mRNAs and found several miRNA–mRNA pairs that are significantly correlated in HepG2 cells. Further analysis suggested that these differentially expressed genes were enriched in four tumorigenesis-related signaling pathways, namely, ErbB, JAK–STAT, mTOR, and WNT, which until now had not been fully reported. Our results could be helpful in understanding the mechanisms of HCC occurrence and development. 相似文献
84.
The clinical interpretation of variants in mismatch repair (MMR) genes associated with Lynch syndrome can be confusing when the functional nature of the variant is not clearly defined. We report an extreme case where a polymorphism in the MSH2 gene which had a low minor allele frequency, was misclassified as a mutation based on low evidential methods in the database and previous publications. We expanded this experience to perform a systematic meta-analysis in order to investigate other variants that have potentially been misclassified. Our results suggested that the interpretation of pathogenicity should be more cautious and emphasized the need for solid validation through multiple analyses including functional analysis for variants in MMR genes. 相似文献
85.
《Bioorganic & medicinal chemistry》2014,22(20):5604-5612
Enzymes catalyze a wide range of biotransformations and have a great potential as environmentally friendly alternatives to classical chemical catalysts in various industrial applications. Recently, advanced techniques and strategies in enzyme discovery and engineering have led to the significant expansion of the quantity and functional diversity of biocatalysts, which has further allowed broader uses of biocatalysts in new processes, especially those traditionally enabled only by chemical catalysts. Here we highlight some of these recent advances with the focus on new approaches in biocatalyst discovery and development, and discuss new applications of selected biocatalysts including transaminases, cytochrome P450s, and Baeyer–Villiger monooxygenases. 相似文献
86.
Mohammad Arif Ashraf Achia Khatun Tanzila Sharmin Faraid Mobin Arifur Rahman Tanu Toufique Morshed Tawkir Ahmad Fakir Rifat Ara Begum AHM Nurun Nabi 《Bioinformation》2014,10(6):384-386
The term of medicinal plants include a various types of plants used in herbalism with medicinal activities. These plants are
considered as rich resources of ingredients which can be used as complementary and alternative medicines and, also in drug
developments and synthesis. In addition, some plants regarded as valuable origin of nutrition. Thus, all these plants are
recommended as therapeutic agents. Information related to medicinal plants and herbal drugs accumulated over the ages are
scattered and unstructured which make it prudent to develop a curated database for medicinal plants. MPDB 1.0 database is
dedicated to provide the first window to find the plants around Bangladesh claimed to have medicinal and/or nutritive values by
accumulating data from the published literatures. This database contains 406 medicinal plants with their corresponding scientific,
family and local names as well as utilized parts for treatment from different districts of Bangladesh. Information regarding
ailments is available for 353 plants. In addition, we have found active compounds for 78 plants with their corresponding PubMed
ID.
Availability
www.medicinalplantbd.net 相似文献87.
88.
89.
文中分析了MIMIC多参数智能监护数据库存储文件的识读方法,该数据库公开发表于PhysioNET,还研究及基于STM32和DAC8568的多参数数据D/A回放系统,包括系统硬件工作原理和系统软件工作原理。MIMIC多参数智能监护数据库的数据文件对于变异性较大的生理参数采用连续采样的方式,而对于相对稳定的生理参数采用周期采样的方式,因此,多参数数据各信号的抽样频率不同。系统首先通过VC++编程读取一个多抽样频率数据并在PC机上显示其波形,然后经过D/A硬件设备进行D/A转换后使用示波器输出其波形,实现输出的波形与原始的波形能同时回放。系统可作为模拟信号源,为远程多参数生理监护仪的研制奠定了基础。 相似文献
90.
目的:肾癌是泌尿系常见肿瘤,需长期随访,传统统计及随访方式已逐渐不能适应现代临床及科研需求,我们尝试建立基于网络的肾癌随访系统,满足临床实际工作和科研需求。方法:以Microsoft Office Access 2007软件构建数据库管理系统,分为资料录入模块、检索分析模块、网络随访模块,选取我院2008.5至2012.12收治的132例肾癌患者,将资料录入已建成的数据库,利用网络随访辅助传统随访方式进行随访。结果:构建的肾癌随访数据库,能够实现授权账户登录,检索、分析、肿瘤自动评级等功能,可根据不同检索条件筛选出适合病历,在传统随访方式的基础上联合应用网络随访方式可提高随访效率及随访率,并能获得更详实的随访资料。结论:基于网络的肾癌随访系统操作简便,能够实现无纸化管理,数据详实,检索便捷,为科学制定治疗方案提供帮助,可一定程度上提高随访率及随访效率,降低失访率和患者就医成本。 相似文献