砧木与接穗间的电波传递

利用嫁接系统研究植物电波的传递表明：（１）无论砧木和接穗共质体连通与否,也无论在嫁接面上加琼脂与否,电波（ＥＷ）均能沿砧木向接穗传递;（２）砧木和接穗共质体连通之前,无论在嫁接面上加琼脂与否,ＥＷ不能沿接穗向砧木传递,砧木和接穗产生的愈伤组织细胞突破隔离层,互相嵌合,产生次生胞间连丝之后,ＥＷ可沿接穗传至砧木;（３）将枝条蒸腾流倒转后进行嫁接,ＥＷ可沿接穗（形态学上部,即插入水中部分）传至砧木（形     

砧木与接穗间的电波传递

利用嫁接系统研究植物电波的传递表明：（１）无论砧木和接穗共质体连通与否,也无论在嫁接面上加琼脂与否,电波（ＥＷ）均能沿砧木向接穗传递;（２）砧木和接穗共质体连通之前,无论在嫁接面上加琼脂与否,ＥＷ不能沿接穗向砧木传递,砧木和接穗产生的愈伤组织细胞突破隔离层,互相嵌合,产生次生胞间连丝之后,ＥＷ可沿接穗传至砧木;（３）将枝条蒸腾流倒转后进行嫁接,ＥＷ可沿接穗（形态学上部,即插入水中部分）传至砧木（形态学下部）,但不能沿砧木传至接穗。     

电波传递在嫁接基本理论研究中的应用

研究发现电波从接穗跃过嫁接面向砧木传递与嫁接的组织学变化相关。砧木和接穗愈伤组织细胞突破隔离层互相嵌合之前,接穗中产生的电波不能传到砧木。砧木和接穗细胞间产生次生胞间连丝后,电波即可沿接穗传至砧木,但此时传递速度慢。当砧木和接穗间产生维管束桥时,电波下传的速度加快。由此可见,通过检测电波跃过嫁接面与否及下传的速度,就可推断嫁接接合部组织学变化状况。电波传递法是一种快速鉴定嫁接植株发育过程的新方法。     

应用蚜虫吻针穿刺技术研究植物的电波传递

目前认为,植物体内的信息传递有三种方式,即水信号、化学信号和电信号[1]。电信号在快速及长距离信息传递中起着重要的作用。现已证明：植物体内的电波传递是一个普遍现象,它能调节许多生理反应[1,2,6,7]。如伸长生长、呼吸作用、水分吸收、韧皮部物质外卸、膨压下降及光合与蒸腾作用的改变、蛋白酶抑制剂基因的激活、气体交换等。在逆境生理的研究中,电信号的作用尤为突出,因为它能迅速地将一个部位感受的信息及时传递到其他部位[4]。目前,在电生理学研究中常使用胞外电极来检测离体组织或整体植株的电波传递;使用胞内电极检测单个…     

植物细胞核的凹入和核液泡的形成

核质互作在细胞核中形成膜囊结构首先是在动物细胞中揭示的［１］。对植物细胞超微结构的研究亦发现有类似现象的存在［２—４］。在植物细胞核中形成的膜泡认为有两种形式：一是核被膜向核基质深度凹入,形成细胞质深入细胞核的状态,称之为“假包被（ｐｓｅｕｄｏ－ｉｎｃｌｕｓｉｏｎ）”［２,５］;另一种形式是细胞核内膜或内外双层核膜向核基质深度凹入,并最终脱离核被膜,在核基质中形成囊泡结构,称之为“核液泡（ｎｕｃｌｅａｒｖａｃｕｏｌｅ）”［３,４,６,７］。对细胞核质间通过核被膜在结构上的特殊作用形式缺少像对通过…     

局部灼伤水田芥引起的电波传递以维管系统为主要通道

局部灼伤水田芥（ＮａｓｔｕｒｔｉｕｍｏｆｆｏｃｉｎａｌｅＲ．Ｂｒ．）叶片可引起动作电波、变异电波和持续电波震荡在茎中传递。本实验举出电波传递的主通道为维管系统。由于水田芥的叶序为２／５,灼伤叶片发出的电波首先传递到其维管束直接联接的第五叶片,随后才传递给临近部位的叶片。若把灼伤叶片和茎节连接的维管束切断,则茎中的电波传递即被阻止。用胞内电极可以检测到基层组织的薄壁细胞也有电波出现。     

成年斑胸草雀在体HVC-RA突触传递的电生理特性

鸣禽高级发声中枢（high vocal center,HVC）至弓状皮质栎核（robust nucleus ofthe arcopallium,RA）的突触传递是鸣唱运动通路中的关键部分.本文运用在体场电位电生理记录的方法,研究了成年雄性斑胸草雀（Taeniopygia guttata）HVC-RA突触的电生理特性.实验结果显示,刺激HVC,在RA内所记录到的诱发场电位幅度较小.配对脉冲检测发现,HVC-RA突触传递具有明显的配对脉冲易化特性.当以强直刺激作用于HVC,RA内诱发场电位随即显著减小,并在15 min内逐渐恢复,表明HVC-RA突触传递在强直刺激过后出现了短时抑制.该通路的突触传递特性可能与其在发声控制中的作用有关.以上的实验结果为进一步研究发声运动过程中的突触可塑性提供了资料.     

泛素活化酶Ube1活性中心疏水区关键苯丙氨酸位点的丙氨酸突变对泛素传递活性的影响

泛素化系统调节真核细胞中几乎所有的生命活动,参与细胞内绝大多数蛋白质的降解,而疾病的发生往往伴随着相关蛋白质的异常。研究与疾病相关蛋白质的泛素化途径,通过该途径促进或抑制其活性对疾病的研究和治疗具有重大的意义。然而,细胞内的泛素传递网络错综复杂,天然条件下很难确认某一特定蛋白质的泛素化途径。我们前期工作建立的正交泛素传递途径中的泛素和泛素化酶含有特殊的突变,是鉴定某一特定E3下游蛋白质底物的有效手段。但E1与E2结合位点的突变设计仍有待完善。本研究重新审视了E1-E2的相互作用,着眼于泛素活化酶Ube1活性中心内的疏水区,突变了该区上3个关键的苯丙氨酸残基为丙氨酸,即F637A、F729A、F741A,并设置合理的实验对照来探究此突变对泛素从E1向E2传递活性的影响。结果表明,突变体m Ube1较好地阻断了与UbcH7的识别及Ub的传递,提示本研究涉及的3个关键苯丙氨酸位点对E1-E2互相识别的重要性,及其作为新的正交泛素传递途径中E1突变位点的合理性。     

亲代传递的独立性与传递不平衡的边缘齐性检验

传递不平衡检验其实质是边缘齐性检验,需同时考察家系中两个亲代向受累子代的传递情形．但是,其零假设成立时,同一家系中父亲的传递与母亲的传递并不一定相互独立．本文探讨了父母传递的独立性条件对检验统计量的影响．结果表明,即使父母传递不独立时,边缘齐性检验仍然适合．     

Application of Electrical Wave Transmission in Basic Research of Grafting

Electrical wave (EW) transmission from scion to stock across the grafting interface was related to the histological changes during the development of graft union. Variation wave (VW) could not be transmitted to stock from scion before isolation layer broken and callus interdigitation. As plasmodesmata formed secondarily at the interface between stock and scion where the isolation layer had disappeared, VW could be transmitted from scion to stock, but its velocity was not rapid until the vascular bridges form between two partners of graft union. Hence, the authors could deduce the degree of graft union formation by measuring whether VW could be transmitted from scion to stock or not and its velocity. EW trans mission method was a new tool for quickly detecting the formation of graft union.     

综述: 无创穿颅电刺激对人脑神经活动和认知功能的调控

穿颅电刺激被认为可以无创调节大脑的神经活动,为研究特定脑区与某一认知功能间的因果关系提供了可能.近些年,对穿颅电刺激作用机制和其对认知、运动功能调控的研究方面取得了很多重要进展.在这篇综述中,我们总结了以往关于穿颅直流电刺激、穿颅交流电刺激和穿颅随机噪声电刺激三种刺激方式的发展历史及其作用机制,同时总结了其对感知觉(主要是视觉知觉)、注意和记忆等认知功能的调控,并对未来的研究方向进行了展望.     

脉冲电场作用对植物释放负离子与气孔特征的关系

植物在自然状态下释放负离子的能力很弱,施加脉冲电场可激发其释放能力。在密闭的玻璃箱中,研究紫背竹芋(Stromanthe sanguinea)、绒叶肖竹芋(Calathea zebrina)和朱顶红(Hippeastrum rutilum)在常态、脉冲电场和光照刺激下释放负离子的浓度,并观察叶片气孔特征,结果表明:(1)不同参数脉冲电场对植物释放负离子的能力影响不同,每种植物均具有高效释放负离子的最佳脉冲电场,紫背竹芋为A3B3C3(A3,U=1.5×104 V;B3,T=1.5 s;C3,?=65 ms);绒叶肖竹芋为A3B4C1(A3,U=1.5×104 V;B4,T=2.0 s;C1,?=5 ms);朱顶红为A4B4C1(A4,U=2.0×104 V;B4,T=2.0 s;C1,?=5 ms)。(2)植物体上所储存的电压越大,其释放负离子的能力越强。(3)脉冲电场作用时,植物释放负离子的能力与光照度呈正相关;无电场刺激时两者差异不显著(P0.05)。(4)植物释放负离子的能力与叶片气孔特征关系密切,脉冲电场作用下叶片气孔的开合度和气孔密度越大,其释放能力越强。     

Retrograde Gastric Electrical Stimulation Reduces Food Intake and Weight in Obese Rats

Objective: To investigate the therapeutic potential of retrograde gastric electrical stimulation (RGES) for obesity in a rodent model of obesity. Research Methods and Procedures: The study was performed in 12 obese Zucker rats implanted with two pairs of gastric serosal electrodes, one pair for stimulation and the other for recording intrinsic gastric myoelectrical activity. It was composed of an acute study in three sessions to study the effect of RGES on intrinsic gastric myoelectrical activity and acute food intake and a chronic phase to study the short‐term effect of RGES on weight. RGES was performed through the distal stomach using long pulses at a frequency of tachygastria (known to induce gastric hypomotility). Results: RGES completely entrained intrinsic gastric myoelectrical activity and turned it into tachygastria at a certain strength. RGES reduced acute food intake compared with the control (p < 0.01). A 2‐week treatment of RGES resulted in a significant reduction in food intake (p = 0.002) and a significantly greater weight loss than sham stimulation (p = 0.004). Discussion: RGES at a tachygastrial frequency reduces food intake and results in weight loss in obese Zucker rats, and its effect is probably attributed to the introduction of tachygastria in the stomach.     

The Interplay Between Disordered Regions in RNAs and Proteins Modulates Interactions Within Stress Granules and Processing Bodies

Condensation, or liquid-like phase separation, is a phenomenon indispensable for the spatiotemporal regulation of molecules within the cell. Recent studies indicate that the composition and molecular organization of phase-separated organelles such as Stress Granules (SGs) and Processing Bodies (PBs) are highly variable and dynamic. A dense contact network involving both RNAs and proteins controls the formation of SGs and PBs and an intricate molecular architecture, at present poorly understood, guarantees that these assemblies sense and adapt to different stresses and environmental changes. Here, we investigated the physico-chemical properties of SGs and PBs components and studied the architecture of their interaction networks. We found that proteins and RNAs establishing the largest amount of contacts in SGs and PBs have distinct properties and intrinsic disorder is enriched in all protein-RNA, protein-protein and RNA-RNA interaction networks. The increase of disorder in proteins is accompanied by an enrichment in single-stranded regions of RNA binding partners. Our results suggest that SGs and PBs quickly assemble and disassemble through dynamic contacts modulated by unfolded domains of their components.     

Electrical Stimulation Accelerates and Enhances Expression of Regeneration-Associated Genes in Regenerating Rat Femoral Motoneurons

1. In this study we investigated whether electrical stimulation accelerates the upregulation of Talpha1-tubulin and GAP-43 (regeneration-associated genes; RAGs) and the downregulation of the medium-molecular-weight neurofilament (NFM), in concert with stimulation-induced acceleration of BDNF and trkB gene expression and axonal regeneration. 2. Two weeks prior to unilateral femoral nerve transection and suture, fluorogold (Fluorochrome Inc., Denver) or fluororuby (Dextran tetramethylrhodamine, Mol. Probes, D-1817, Eugene, OR) was injected into quadriceps muscles of the left and right hindlimbs to label the femoral motoneuron pools as previously described. Over a period of 7 days, fresh spinal cords were processed for semiquantitation of mRNA by using in situ hybridization. 3. There was an increase in Talpha1-tubulin and GAP-43 mRNA and a decline in the NFM mRNA at 7 days after nerve suture and sham stimulation but not in intact nerves. In contrast, 1-h stimulation of sutured but not intact nerves dramatically accelerated the changes in gene expression: mRNA levels of Talpha1-tubulin and GAP-43 were significantly elevated above control levels by 2 days while NFM mRNA was significantly reduced by 2 days in the sutured nerves. Thereby, the neurofilament/tubulin expression ratio was reduced at 2 days after suture and stimulation, possibly allowing more tubulin to be transported faster into the growing axons to accelerate the elongation rate following stimulation. Importantly, the changes in RAGs and NFM gene expression were delayed relative to the accelerated upregulation of BDNF and trkB mRNA by electrical stimulation. 4. The temporal sequence of upregulation of BDNF and trkB, altered gene expression of RAGs and NFM, and accelerated axonal outgrowth from the proximal nerve stump are consistent with a key role of BDNF and trkB in mediating the altered expression of RAGs and, in turn, the promotion of axonal outgrowth after electrical stimulation.     

不同类型心力衰竭患者心电图QRS波时限与血浆NT-proBNP水平的关系及其临床意义

目的：探讨不同类型心力衰竭患者心电图QRS 波时限与血浆N末端B型利钠肽原（NT-proBNP）水平之间的关系及其临床 意义。方法：选择我院2012 年7 月至2014 年6 月接收的慢性心力衰竭患者300 例,作为研究组,将患者分为收缩性心力衰竭组 （S组）和舒张性心力衰竭组（D组）;另外,选取我院非CHF 患者132 例,作为对照组。测定所有受试者的心电图QRS 波时限,及 血浆中NT-proBNP 水平,分析血浆NT-proBNP 水平与QRS 波时限及NYHA心功能分级关系。结果：与对照组相比,研究组QRS 波时限均延长,血浆NT-proBNP水平显著升高（P<0.05）,其中S 组比D 组明显延长,且S 组血浆NT-proBNP水平高于D 组 （P<0.05）。三组NYHA 分级对比发现,差异均具有统计学意义（P<0.05）;S 组患者血浆NT-proBNP水平与QRS 波时限及NYHA 心功能分级之间呈正相关;D 组患者血浆NT-proBNP水平与QRS 波时限及NYHA心功能分级之间无明显的相关性。结论：临床 上可以将NT-proBNP水平和QRS 波时限结合起来诊断慢性心力衰竭患者的类型,以便于之后的治疗。     

功能性电刺激联合循环运动系统对老年脑卒中后肌肉衰减综合征患者肢体功能、平衡能力以及认知功能的影响

摘要 目的：研究功能性电刺激联合循环运动系统对老年脑卒中后肌肉衰减综合征患者肢体功能、平衡能力以及认知功能的影响。方法：选择2020年6月到2021年6月在我院进行康复治疗的老年脑卒中后肌肉衰减综合征患者64例,据其治疗方式的不同分为对照组和研究组,两组患者均给予常规康复治疗,对照组患者在常规治疗的基础上加用功能性电刺激治疗,而研究组在对照组基础上加用脑循环系统治疗仪进行治疗,比较两组患者临床治疗疗效。使用运动功能评分法（FMA）和上肢功能评定（STEF）评价肢体患者功能,使用平衡量表（BBS）和Fuglg-Meyer平衡量表（FM-B）评价患者平衡能力,使用自拟认知量表评价患者认知功能。结果：（1）研究组患者临床治疗总有效率较对照组高（93.75 % vs 75.00 %,P<0.05）;（2）两组患者治疗后FMA和STEF评分均显著增高（P<0.05）,并且研究组患者治疗后BBS和FM-B评分显著高于对照组患者（P<0.05）;（3）两组患者治疗后BBS和FM-B评分均显著增高,并且研究组患者治疗后BBS和FM-B评分显著高于对照组患者（P<0.05）;（4）两组患者治疗后认知功能评分均升高,并且研究组患者较对照组患者高（P<0.05）。结论：功能性电刺激联合循环运动系统对老年脑卒中后肌肉衰减综合征患者具有显著的临床治疗效果,可显著改善患者肢体功能、平衡能力和认知功能。