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Intrinsic Noise Monitoring of Complex Systems 复杂系统的固有噪声监测
Pub Date : 2017-07-31 DOI: 10.4236/OJBIPHY.2017.74015
O. Szász, G. Szigeti, A. Szász
The power-density function of the noise spectrum of open and complex systems changes by the power of frequency. We show that the fluctuation origin and the noise-powered description are equivalent to describe the colored noise power density. Based on this, we introduce a scale-independent invariant for monitoring the dynamics of the complex system. The monitoring of the noise spectrum of the system specifies the forecast of failure, the timing of desired regular corrections and/or the assessed operation life of the system, indicating the possible faults before it happens, predicting deterioration like wear/tear, fatigue in the still properly working system. These considerations are highly applicable to living systems and their preventive care.
开放复杂系统噪声谱的功率密度函数随频率的功率变化。我们证明了波动源和噪声功率描述等价于描述有色噪声功率密度。在此基础上,我们引入了一个与尺度无关的不变量来监测复杂系统的动力学。系统噪声谱的监测规定了故障的预测、所需定期校正的时间和/或系统的评估运行寿命,在故障发生之前指示可能的故障,预测仍然正常工作的系统中的磨损、疲劳等恶化。这些考虑因素高度适用于生活系统及其预防性护理。
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引用次数: 2
Contribution of Myocardial Perfusion’s Tomoscintigraphy in the Management of Coronarian Disease in Senegal: About 42 Cases 心肌灌注断层摄影在塞内加尔冠状动脉疾病治疗中的作用:约42例
Pub Date : 2017-07-31 DOI: 10.4236/OJBIPHY.2017.74013
B. Ndong, G. Mbaye, E. Bathily, O. Diop, A. Diop, L. Diouf, A. Mbaye, R. S. Senghor, M. Soumboundou, A. Djiboune, P. M. Sy, N. Badji, A. Dia, M. S. Djigo, M. Mbodj, O. Ndoye, M. Diarra, A. Kane, S. Seck-gassama
The aim of the study was to evaluate the contribution to moscintigraphy of myocardial perfusion (TSMP) with 99mTc-sestamibi in the management of suspected or known coronary patients’s population. It included 42 patients with an average age of 57.02 ± 9.77 years with extremes ranging from 36 to 77 years. The pre-test probability in 38 patients was high in 7 patients (18.42%), intermediate in 29 patients (76.31%) and low in 2 patients (5.26%). Patients with a high pre-test probability had a positive scintigraphy. Among the 26 patients who underwent transthoracic ultrasound (TTU), 10 with normal kinetics on trans-thoracic ultrasound (TTU) had positive scintigraphy. For 16 patients with TTU abnormalities, 6 had negative scintigraphy and 10 had positive scintigraphy. The TSMP was positive for 28 patients (66.66%). Among these patients, 16 had pure ischemia, 57.14% (16/28), 7 pure necrosis (25%), and 5 both necrosis and ischemia. Myocardial perfusion scintigraphy remains a very contributory consideration in the management of coronary disease. This is synchronized with the electrocardiogram (ECG) and is an important diagnostic and prognostic tool for coronary artery disease. It also provides a good indication of coronary angiography.
本研究的目的是评估99mTc-sestamibi对疑似或已知冠状动脉患者群体的心肌灌注(TSMP)动态描记术的贡献。包括42名患者,平均年龄57.02±9.77岁,极端年龄36至77岁。38例患者的测试前概率为高7例(18.42%),中等29例(76.31%),低2例(5.26%)。测试前概率高的患者闪烁扫描呈阳性。在26例接受经胸超声(TTU)检查的患者中,10例经胸超声动力学正常的患者闪烁扫描呈阳性。16例TTU异常患者中,6例闪烁扫描阴性,10例闪烁扫描阳性。TSMP阳性28例(66.66%),其中单纯缺血16例,57.14%(16/28),单纯坏死7例(25%),坏死和缺血各5例。心肌灌注闪烁扫描在冠状动脉疾病的治疗中仍然是一个非常重要的考虑因素。这与心电图同步,是冠状动脉疾病的重要诊断和预后工具。它还提供了冠状动脉造影的良好指示。
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引用次数: 0
On the Self-Similarity in Biological Processes 论生物过程中的自相似性
Pub Date : 2017-07-31 DOI: 10.4236/OJBIPHY.2017.74014
O. Szász, G. Szigeti, A. Szász
We show that the processes described by Avrami functions are self-similar. A comparative function characterizes a self-similar process by a certain Avrami exponent. We define the self-similar categories of some well-known biological processes. The method to determine the Avrami exponent by choosing the comparative function is demonstrated on the diffusion model of the growth of nuclei. We generalize the results.
我们证明了Avrami函数描述的过程是自相似的。比较函数用一定的Avrami指数来表征自相似过程。我们定义了一些众所周知的生物过程的自相似类别。在核生长的扩散模型上,给出了选择比较函数确定Avrami指数的方法。我们推广结果。
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引用次数: 8
Energy Absorption by the Membrane Rafts in the Modulated Electro-Hyperthermia (mEHT) 膜筏在调制电热(mEHT)中的能量吸收
Pub Date : 2017-07-31 DOI: 10.4236/OJBIPHY.2017.74016
Edina Papp, T. Vancsik, É. Kiss, O. Szász
Aim: Heating by nanoparticles, which are located in the tissue to be treated, is a well-recognized method in hyperthermic oncology. Our objective is to investigate selective, nanoscopic heating without concentrating extra artificial nanoparticles. We have in silico calculation to study the heating of the transmembrane protein clusters (rafts) on cell-membrane. The transmembrane protein domains have significantly higher dielectric constant than their lipid neighborhood in the membrane. This difference causes a local gradient in the Specific Absorption Rate (SAR), which could be a factor of heating of the membranes locally, as well as exciting the receptors for various signal transduction in the cells. We suppose that this process determines the observed cellular effects of modulated electro-hyperthermia (mEHT, trade-name: oncothermia). Materials and Methods: In silico models with highly specialized software (Computer Simulation Technology (CST), Darmstadt, Germany) were performed visualizing the selectivity for the membrane domains. Local raft models were created to simulate the electromagnetic (EM) effect of a 13.56 MHz excitation between two perfect electrical conductor plates, simulating the equipotential conditions of the sides of the membrane in the vicinity of the raft. The simulations were performed with near-field (EQS) solver of CST. The electric field, current density, and electric loss density were monitored by the simulations. The applied material properties and parameters refer to the recent literature. Results: In silico models show ten times higher energy-absorption of the transmembrane domains than that of its lipid-membrane surrounding, and intra- and extracellular neighborhood. Depending on the size, orientation, and location of the membrane rafts, the value of SAR varies, but we use only two simplified models to see the absorption properties. Taking into account the characteristics of the EM field effects we showed that the selective energy-absorption increased further by the cell-cell interactions. The model-calculation could confirm the opportunity of the local membrane heating. Conclusion: Our results indicate the heating in nanoscopic range with energy-absorption by the transmembrane proteins. The heated protein-clusters (membrane rafts) are used the same way as the artificial nanoparticles, while these absorbers are natural parts of the biological system.
目的:位于待治疗组织中的纳米颗粒加热是热疗肿瘤学中公认的方法。我们的目标是在不浓缩额外人工纳米颗粒的情况下研究选择性的纳米级加热。我们用计算机计算来研究细胞膜上跨膜蛋白簇(rafts)的加热。跨膜蛋白结构域的介电常数明显高于其在膜中的脂质邻域。这种差异导致比吸收率(SAR)的局部梯度,这可能是局部加热膜以及刺激细胞中各种信号转导的受体的一个因素。我们假设这一过程决定了所观察到的调制电热疗(mEHT,商品名:oncothermia)的细胞效应。材料和方法:使用高度专业化的软件(计算机模拟技术(CST),德国达姆施塔特)进行计算机模型,可视化膜结构域的选择性。创建了局部筏板模型,以模拟两个理想导电板之间13.56MHz激励的电磁(EM)效应,模拟筏板附近薄膜侧面的等电位条件。使用CST的近场(EQS)求解器进行了仿真。通过模拟监测了电场、电流密度和电损耗密度。应用的材料特性和参数参考最近的文献。结果:在计算机模型中,跨膜结构域的能量吸收是其脂质膜周围、细胞内和细胞外邻域的十倍。根据膜筏的大小、方向和位置,SAR的值各不相同,但我们只使用两个简化模型来观察吸收特性。考虑到EM场效应的特征,我们发现细胞与细胞的相互作用进一步增加了选择性能量吸收。模型计算可以确定局部膜加热的机会。结论:我们的结果表明,跨膜蛋白在纳米范围内具有能量吸收。加热的蛋白质簇(膜筏)的使用方式与人造纳米颗粒相同,而这些吸收剂是生物系统的天然组成部分。
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引用次数: 22
Heating Preciosity—Trends in Modern Oncological Hyperthermia 加热精度——现代肿瘤热疗的发展趋势
Pub Date : 2017-05-15 DOI: 10.4236/OJBIPHY.2017.73010
O. Szász, M. Szász, C. Minnaar, A. Szász
The use of hyperthermia as a treatment in oncology is a common topic for debate. Some researchers expect a breakthrough in oncological treatments with hyperthermia, whereas others have disregarded the method. Serious questions concerning hyperthermia have arisen. Should homogeneous (isothermal) or heterogeneous (selective) heating being used? When we use selective heating (heterogeneity), should the entire tumour be targeted or should the malignant cells be individually selected? Does the mechanism involve thermal cell death or thermally-assisted cell death? Is the goal necrosis or apoptosis? Is hyperthermia safe as a monotherapy or does it have to be combined with conventional treatments? When the selection is local, how do we act on disseminated cells that represent a high risk of life threatening metastases? When local heating is the focus, how should it be carried out with measured and controlled? Our objective is to show how precise, selective heat transfer is necessary to remove malignant cells and, consequently, how hyperthermia as part of the immune-oncology can change the game in this promising field of oncological therapies.
热疗在肿瘤学中的应用是一个常见的争论话题。一些研究人员预计热疗在肿瘤学治疗方面会取得突破,而另一些人则忽视了这种方法。出现了关于热疗的严重问题。应该使用均匀(等温)加热还是非均匀(选择性)加热?当我们使用选择性加热(异质性)时,是应该靶向整个肿瘤,还是应该单独选择恶性细胞?该机制是否涉及热细胞死亡或热辅助细胞死亡?目标是坏死还是凋亡?热疗作为单一疗法安全吗?还是必须与传统疗法相结合?当选择是局部的时,我们如何对具有高生命危险转移风险的播散细胞采取行动?当局部供暖成为焦点时,应如何进行测量和控制?我们的目标是展示精确、选择性的传热对于去除恶性细胞是多么必要,从而展示热疗作为免疫肿瘤学的一部分如何改变肿瘤学治疗这一有前景的领域的游戏。
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引用次数: 14
Non-Thermal Radio Frequency Stimulation Inhibits the Tryptophan Synthase Beta Subunit in the Algae Chlamydomonas reinhardtii 非热射频刺激抑制莱茵衣藻色氨酸合成酶β亚基
Pub Date : 2017-05-15 DOI: 10.4236/OJBIPHY.2017.73007
B. M. Butters, G. Vogeli, Xavier A. Figueroa
To demonstrate the ability of the Nativis signal transduction technology (Butters et al. 2014) to modulate the expression of algae mRNA and protein, we tested if we can alter specific enzyme levels in Chlamydomonas reinhardtii. We inhibited the synthesis of the enzyme tryptophan synthase beta subunit (MAA7) by applying the signal derived from a published siRNA (Zhao et al. 2009). With lower levels of MAA7, Chlamydomonas reinhardtii can grow in the presence of the prodrug 5-Fluoroindole (5-FI), because less 5-Fluoroin-dole can be converted to the toxic 5-Fluoro-L-tryptophan (5-FT). We find a 24% (±5%) increase of growth with the signal versus no signal. To see if that effect was due to the reduction of the amount of mRNA encoding MAA7, we used Real-Time Quantitative PCR (RT-QPCR) to measure the levels of MAA7 mRNA. To normalize the MAA7 mRNA level, we compared them to the levels of a mRNA that is not affected by the signal (G protein beta subunit-like polypeptide, Cblp). Two conditions increase the effectiveness of the signal. One can either treat the cell cultures during the logarithmic growth phase (starting the cultures at density of 0.104 OD at 750 nm). Or one can treat the cultures at a later stage of the logarithmic growth, but treating them for a longer time (8.7% versus 3.5% of the culture time). Under these conditions we found around a 50% decrease in the mRNA levels for MAA7. Treating the cultures at the earlier growth phase or at a later growth phase is less effective, with only a 20% effect.
为了证明Nativis信号转导技术(Butters等人,2014)调节藻类mRNA和蛋白质表达的能力,我们测试了是否可以改变莱茵衣藻中的特定酶水平。我们通过应用来源于已发表的siRNA的信号来抑制色氨酸合酶β亚基(MAA7)的合成(赵等人,2009)。在MAA7水平较低的情况下,莱茵衣藻可以在前药5-氟吲哚(5-FI)存在下生长,因为较少的5-氟吲哚可以转化为有毒的5-氟-L-色氨酸(5-FT)。我们发现,与没有信号相比,有信号的生长增加了24%(±5%)。为了观察这种影响是否是由于编码MAA7的mRNA量的减少,我们使用实时定量PCR(RT-QPCR)来测量MAA7 mRNA的水平。为了使MAA7 mRNA水平正常化,我们将其与不受信号影响的mRNA(G蛋白β亚基样多肽,Cblp)的水平进行了比较。有两种情况可以提高信号的有效性。可以在对数生长阶段处理细胞培养物(在750nm下以0.104OD的密度开始培养物)。或者,可以在对数生长的后期处理培养物,但处理时间更长(培养时间的8.7%对3.5%)。在这些条件下,我们发现MAA7的mRNA水平下降了约50%。在早期生长阶段或后期生长阶段处理培养物的效果较差,只有20%的效果。
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引用次数: 0
Quantifying Biofilm Formation of Sinorhizobium meliloti Bacterial Strains in Microfluidic Platforms by Measuring the Diffusion Coefficient of Polystyrene Beads 通过测量聚苯乙烯珠的扩散系数来定量微流体平台中梅洛蒂中华根瘤菌菌株的生物膜形成
Pub Date : 2017-05-15 DOI: 10.4236/OJBIPHY.2017.73012
Chengcheng Cheng, Yijun Dong, M. Dorian, F. Kamili, Effrosyni Seitaridou
Though the majority of bacteria can form structured communities known as biofilms, mutations can cause bacterial strains to vary in their ability to form a biofilm. In this study, the apparent diffusion coefficient of polystyrene microspheres 0.29 μm in diameter, which were executing Brownian motion inside bacterial colonies, was used as a quantitative parameter of the ability of a strain to form a biofilm and of the biofilm development. The study was performed using five Sinorhizobium meliloti strains, the biofilm-forming strains Rm8530 expR+, Rm8530 exoY, and Rm9034 expG, and the non-biofilm forming strains Rm1021 and Rm9030-2 expA1. The green fluorescent beads were placed with each strain in a separate channel of a microfluidic device. Thus, as the bacterial colonies grew under identical conditions over a 4-day period, the motion of the fluorescent microspheres was recorded and the diffusion coefficients were measured every 24 hours via particle tracking algorithms. It was found that each strain displayed a unique pattern of change in diffusion coefficient over time. Also, for a given biofilm-forming strain, there was a clear correlation between the value of the diffusion coefficient and the appearance and motility of the bacterial community. Thus, the diffusion coefficient can be used to identify different S. meliloti strains, and for the biofilm-forming strains, it is also a quantitative indicator of the stage of biofilm development.
尽管大多数细菌可以形成被称为生物膜的结构化群落,但突变会导致细菌菌株形成生物膜的能力发生变化。在本研究中,直径为0.29μm的聚苯乙烯微球在菌落内进行布朗运动,其表观扩散系数被用作菌株形成生物膜能力和生物膜发育的定量参数。本研究使用五株中华根瘤菌、形成生物膜的菌株Rm8530-expR+、Rm8530-exoY和Rm9034-expG,以及未形成生物膜菌株Rm1021和Rm902-expA1进行。将绿色荧光珠与每个菌株一起放置在微流体装置的单独通道中。因此,当菌落在相同条件下生长4天时,记录荧光微球的运动,并通过粒子跟踪算法每24小时测量一次扩散系数。研究发现,随着时间的推移,每个菌株的扩散系数都表现出独特的变化模式。此外,对于给定的生物膜形成菌株,扩散系数的值与细菌群落的外观和运动性之间存在明显的相关性。因此,扩散系数可以用来识别不同的S.meliloti菌株,对于形成生物膜的菌株来说,它也是生物膜发育阶段的定量指标。
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引用次数: 1
The Effects of Tissue Regenerative Status on Hormesis in Dogs Irradiated during Their Lifespan 组织再生状态对狗一生中受辐射后激素的影响
Pub Date : 2017-05-15 DOI: 10.4236/OJBIPHY.2017.73009
A. N. Shoutko, L. P. Ekimova
The goal of this study was to evaluate the influence of natural variation in the regenerative status of dog tissues on the signs of hormesis, which are evident after total body exposure to low daily doses of external gamma radiation throughout the lifespan. Ninety beagle dogs of both sexes were irradiated with cobalt 60 at 0.003 Gy/day commencing 1 year after birth to death. Control (n = 169) and irradiated animals underwent whole-life clinical observation and autopsy, and were then retrospectively divided into two subgroups with (W) or without benign tumors or tumors of unknown nature (WO) that were clinically recorded on single days throughout the lifespan. Radiation hormesis was only detected in subgroup WO, which had life span (LS) of 10.7 years in the absence of radiation. The radiogenic prolongation of life to 11.8 years in the WO subgroup (p 0.05) was similar to that in the W control and irradiated W subgroups (11.8 and 11.5 years, respectively). The number of solid malignancies found upon autopsy of the control WO subgroup was less (39.5%) than that evident in the control W subgroup (60%). Compared to the irradiated W subgroup, irradiation of the WO subgroup was accompanied by a slight increase (1.14-fold) in the number of solid malignancies evident at autopsy and in the clinical signs of tissue atrophy and body weight loss (2.4-fold and 2.4-fold, respectively), but was accompanied by strong reductions in the extent of anemia and hemoblastoses (>10-fold for both). The data exclude the notion that radiation is associated with healing, but suggest that certain pathologies (e.g., hemoblastoses) may be substituted with other less dangerous somatic diseases in weaker animals only.
这项研究的目的是评估狗组织再生状态的自然变化对兴奋症状的影响,在整个生命周期中,全身暴露于低剂量的每日外部伽马辐射后,兴奋症状很明显。从出生后1年至死亡,对90只两性比格犬进行0.003 Gy/天钴60辐照。对照组(n=169)和受照射动物接受了终身临床观察和尸检,然后回顾性地分为两个亚组,其中有(W)或没有良性肿瘤或性质未知的肿瘤(WO),在整个生命周期的一天内进行临床记录。辐射刺激只在WO亚组中检测到,在没有辐射的情况下,WO的寿命(LS)为10.7年。WO亚组的放射性寿命延长至11.8年(p 0.05)与W对照组和辐照W亚组(分别为11.8年和11.5年)相似。对照WO亚组尸检发现的实体恶性肿瘤数量(39.5%)少于对照W亚组(60%)。与辐照的W亚组相比,WO亚组的辐照使尸检时明显的实体恶性肿瘤数量以及组织萎缩和体重减轻的临床症状略有增加(1.14倍)(分别是2.4倍和2.4倍),但同时贫血和血母细胞增多症的程度显著降低(两者均>10倍)。这些数据排除了辐射与愈合有关的概念,但表明某些病理学(如血母细胞增多症)可能仅在较弱的动物中被其他危险性较低的躯体疾病所取代。
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引用次数: 6
Evaluation of the Effects of Irradiation of Peanut Grain by a Gamma-Ray Beam on Culture γ射线辐照花生籽粒培养效果的评价
Pub Date : 2017-05-15 DOI: 10.4236/OJBIPHY.2017.73008
G. Mbaye, M. Soumboundou, L. Diouf, B. Ndong, A. Djiboune, P. M. Sy, S. Dieng, M. Diouf, N. Diouf, A. Barry, M. Diarra
The problems of agriculture in Senegal result in a low yield per hectare and poor seed quality contributing strongly to the decline in productivity. Mutagenesis by X- or Y-ray irradiation makes it possible to obtain genetic mutants necessary to improve production. It is in this context that we undertook this study to evaluate the effects induced on the cultivation of peanut seeds irradiated by X-rays at low doses applied in radiotherapy. X-ray irradiation of four (2, 3, 4, 5) lots of peanuts are performed with respectively 0.5, 1.5, 2 and 4 Gray using the cobalt 60 therapy device (Alcyon II). The seeding of the seeds and then the following-up of the crops during 35 days allowed us to study the parameters of germination, growth and yield. The results obtained after monitoring revealed that the irradiation did not have any significant impact on germination and would appear to temporarily inhibit the growth rate compared to the control batch. However, the decrease in weight of the harvested seeds can be explained by the absence of fertilizer during the cultivation.
塞内加尔的农业问题导致每公顷产量低,种子质量差,这是生产力下降的主要原因。通过X射线或Y射线照射诱变,可以获得提高产量所需的遗传突变体。正是在这种背景下,我们进行了这项研究,以评估低剂量X射线在放射治疗中对花生种子培养的影响。使用钴60治疗装置(Alcyon II)分别用0.5、1.5、2和4格雷对四(2、3、4、5)批花生进行X射线照射。种子播种,然后在35天内对作物进行随访,使我们能够研究发芽、生长和产量的参数。监测后获得的结果显示,与对照批次相比,辐照对发芽没有任何显著影响,并且似乎暂时抑制了生长速率。然而,收获的种子重量的减少可以解释为栽培过程中没有肥料。
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引用次数: 8
Two Small Molecules, ZCL278 and AZA197 Show Promise in Influencing Protein Interactions Involving the Ras-Related Protein Cell division cycle 42 [Cdc42] to Modulate Its Oncogenic Potential 两种小分子ZCL278和AZA197有望影响涉及Ras相关蛋白细胞分裂周期42[Cdc42]的蛋白质相互作用,以调节其致癌潜力
Pub Date : 2017-05-15 DOI: 10.4236/OJBIPHY.2017.73006
D. Muhoza, P. Adams
Cdc42 is a member of the Rho subfamily of Ras-related proteins, which were among the first oncogenic proteins to be identified as playing a sig-nificant role in a variety of cellular events [Barbacaid, 1987, Ann. Rev. Biochem]. Equally important, Protein-Protein Interactions [PPIs] involving Cdc42 continue to highlight the role of Ras-related proteins’ relevance to cancer. As these proteins have been considered incapable of being “druggable”, due to a perceived lack of binding surface[s] that are amenable to small molecule targeting, there remains limited development of therapies to tackle diseased states caused by Cdc42-stimulated hyperactivity. Thusly, it has become important to characterize molecular details, including dynamics, of PPIs involving Cdc42 that may lend themselves as potential targets for therapeutic approaches. Recently, two small molecules, ZCL278 and AZA197, have shown promise in directly targeting Cdc42 to influence PPIs that are capable of causing Cdc42-stimulated abnormal signaling. In this editorial, we highlight recent studies that show case how these two small molecules may influence Cdc42-protein interactions.
Cdc42是Ras相关蛋白Rho亚家族的一员,其是首批被鉴定为在各种细胞事件中发挥重要作用的致癌蛋白之一[Babacaid,1987,Ann.Rev.Biochem]。同样重要的是,涉及Cdc42的蛋白质-蛋白质相互作用(PPIs)继续强调Ras相关蛋白与癌症的相关性。由于这些蛋白质被认为不能“药用”,因为人们认为缺乏适合小分子靶向的结合表面,因此解决Cdc42刺激的多动症引起的疾病状态的疗法发展有限。因此,表征涉及Cdc42的PPI的分子细节(包括动力学)变得很重要,这些分子细节可能成为治疗方法的潜在靶点。最近,两种小分子ZCL278和AZA197已显示出直接靶向Cdc42以影响能够引起Cdc42刺激的异常信号传导的PPI的前景。在这篇社论中,我们重点介绍了最近的研究,这些研究表明了这两个小分子如何影响Cdc42蛋白的相互作用。
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引用次数: 6
期刊
生物物理学期刊(英文)
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