凋亡过程中膜联蛋白V（AnnexinV）的检测

1原理 细胞凋亡具的各种不同的形态学特征,细胞膜的改变是最早的变化之一.在凋亡细胞,位于细胞膜内的磷脂酰丝氨酸( phospholipid phosphatidyl-serine, PS)转位到细胞膜外.膜联蛋白V是一种35～36kDa的钙依赖的.磷脂结合蛋白,其与PS有高度的亲和性,能与表达ps的细胞结合.膜联蛋白可与萤光染料异硫氰酸FITC或生物素(biotin)结合.因此可用于流式细胞术检测凋亡过程中的细胞.     

糖基化磷脂酰肌醇锚定蛋白转化法——一门全新的细胞表面工程学

糖基化磷脂酰肌醇(GPI)锚定蛋白是一种新型细胞表面蛋白,它只通过GPI结构锚定于细胞膜表面而不跨越其磷脂膜双层结构;当它与细胞共同孵育时,可自动整合至细胞膜表面。GPI锚定蛋白转化法利用GPI锚定信号将目的蛋白直接整合至靶细胞表面,超越了目的蛋白由靶细胞自身合成的机制,具有对靶细胞选择性不高,转化过程迅速等优点,在抗原提呈细胞工程、肿瘤疫苗及移植物抗排斥反应等研究领域得到了广泛应用。     

慢性肾衰竭病人红细胞表面磷脂酰丝氨酸的表达

目的: 研究血液透析(HD)、腹膜透析(CAPD)、无透析慢性肾衰竭(Non-D)病人及正常人红细胞表面磷脂酰丝氨酸(PS)的表达情况, 以探讨PS的表达对红细胞功能影响的关系。方法: 采用对PS有高度亲和力的磷脂结合蛋白annexin V检测技术, 利用流式细胞仪对细胞进行荧光测定。结果: HD病人红细胞PS的表达较高(2113±1112)%, CAPD组(1135±0184)%和Non-D病人(1139±0170)%相对较低, 但都明显高于正常人对照组(0171±0134)%。结论: 慢性肾衰竭(CRF)病人PS的高表达与尿毒症之间有明显的相关性。     

磷脂对脂多糖诱导中性粒细胞CD11a表达的影响

本实验主要研究与磷脂作用后脂多糖（lipopolysaccharide,LPS)生物学活性的变化。用与不同磷脂预卵育后的LPS刺激细胞,检测中性粒细胞的粘附功能及巨噬细胞分泌细胞因子功能的变化。结果发现与磷脂卵育后,LPS可插入磷脂脂质体膜中,使中性粒细胞粘附功能降低,巨噬细胞分泌细胞因子减少。结果提示LPS6插入细胞磷脂中可以改变其生物活性,推测细胞膜磷脂成分降解可能是LPS诱发炎症反应的重要原因。     

小胶质细胞体外吞噬模型的建立及相关炎症因子的研究

目的: 建立以细胞凋亡信号－磷脂酰丝氨酸(PS)介导的小胶质细胞体外吞噬模型,研究小胶质细胞发挥吞噬功能时炎症因子的表达变化。方法: 用N-乙基马来酰胺(NEM)预处理红细胞,随后整合氧化PS,制备含氧化PS信号的红细胞凋亡模型,并测定小胶质细胞对整合氧化PS信号红细胞吞噬率的变化。同时, real-time PCR检测小胶质细胞中炎症因子白细胞介素1β(IL-1β)和肿瘤坏死因子(TNF-α)的表达情况,研究小胶质细胞吞噬功能与炎症功能之间的关系。结果: 小胶质细胞对整合氧化PS红细胞的吞噬率显著高于对照组(P<0.01),同时炎症因子IL-1β和TNF-α的mRNA表达水平明显减少。结论: 成功制备小胶质细胞体外吞噬凋亡细胞模型,小胶质细胞的吞噬作用可能是自身炎症因子IL-1β和TNF-α在转录水平上降低的诱因。     

脑梗塞患者红细胞变形能力与膜磷脂组分的关系

为探讨脑梗塞患者红细胞膜磷脂各组分对红细胞变形能力的影响，采用高效液相色谱法对58例脑梗塞患者和26名健康人的红细胞膜磷脂各组分进行了测定，并同时检测了其红细胞胆固醇含量及红细胞变形能力。结果表明，脑梗塞患者红细胞膜磷脂酸胆碱（PC）、磷脂酸乙醇胺（PE）含量降低，胆固醇（CHO）含量升高，红细胞变形能力降低。直线相关分析，膜PC与红细胞滤过指数呈显著负相关。结论：脑梗塞患者红细胞膜你在以PE、PC变化为主的磷脂代谢紊乱，膜PC异常可能是影响红细胞变形能力的一个重要因素。     

陡脉冲电场对体外人肝癌细胞SMMC-7721的诱导凋亡作用

为研究陡脉冲电场的诱导凋亡作用,以体外人肝癌细胞SMMC-7721为实验对象,采用Annexin V-FITC/PI双染色并利用流式细胞术检测磷脂酰丝氨酸(PS)外翻,采用琼脂糖凝胶电泳检测DNA降解片段化.实验发现,陡脉冲电场能有效(P<0.05)地使PS外翻,并且微秒级陡脉冲(μsSPEF)比纳秒级陡脉冲(nsSPEF)更有效(P<0.05);陡脉冲电场能使DNA降解片段化,且nsSPEF比μsSPEF更有效.实验结果表明,陡脉冲电场能有效诱导体外人肝癌细胞凋亡,其机理与陡脉冲电场非热效应及其频谱特性有关.μsSPEF主要作用于细胞膜,而可能通过外源性通路诱导细胞凋亡;nsSPEF主要作用于细胞核和线粒体等胞内细胞器,可能通过内源性通路诱导细胞凋亡.实验结果为陡脉冲电场杀伤肿瘤细胞的机制和参数选择提供了依据.     

反复自然流产及不孕症患者中抗心磷脂抗体的检测

抗心磷脂抗体 (ａｎｔｉｃａｒｄｉｏｌｉｐｉｎａｎｔｉｂｏｄｙ ,ＡＣＡ)系一种酸性磷脂的异质性自身抗体 ,靶抗原为带负电的磷脂成分 ,并参与多种细胞膜的组成 ,为了解反复自然流产 (ＲＳＡ)及女性不孕症患者中ＡＣＡ的阳性率及其临床意义 ,我们应用ＥＬＩＳＡ法对 2 0 3例女性不孕症患者 ,49例ＲＳＡ患者及 30例体检健康女性进行了ＡＣＡ检测 ,并对其阳性患者进行了ＩｇＧ、ＩｇＡ及ＩｇＭ分型。现将结果报告如下。资料与方法一、受检标本 :女性不孕症患者血清标本 2 0 3例 (均为结婚 2年以上未孕者 ) ,年龄 2 5 - 35岁 ;ＲＳＡ患者 49…     

习惯性流产妇女与自身抗体之间关系的探讨

目的了解抗心磷脂抗体、抗人绒毛膜促性腺激素抗体、抗滋养细胞膜抗原抗体与习惯性流产患者之间的关系.方法用ELISA法试剂盒.测定习惯性流产妇女血清中的抗心磷脂抗体、抗绒毛膜抗促性腺激素抗体、抗滋养细胞膜抗原抗体的结果.结果与对照组比较抗心磷脂抗体阳性率为24.41%,有极显著性差异(P＜0.01);抗人绒毛膜促性腺激素抗体其阳性率为29.06%,有极显著性差异(P＜0.01);抗滋养细胞膜抗原抗体阳性率为24.41%有极显著性差异(P＜0.01).结论抗心磷脂抗体、抗人绒毛膜促性腺激素抗体、抗滋养细胞膜抗原抗体与习惯性流产患者之间有着极为密切的关系.     

海马提取物调控PI4-K激酶活性

目的海马是一种具有抗衰老、抗疲劳及抗肿瘤的中药,迄今对其分子作用机制不十分清楚。肌醇磷脂激酶(PI4-K)作为PI信号通路中起重要作用的激酶,位于信号通路的上游,应是寻找新药十分关键的靶分子。方法利用人红细胞膜内翻外的技术,将存在于细胞膜内侧的肌醇磷脂激酶(PI4-K)暴露在外,成为IOV-PI4-K抗原蛋白;用IOV-PI4-K抗原蛋白与其PI4-K单克隆抗体(A6D)的ELISA检测技术,对海马提取物进行了初步研究。结果从海马提取物中筛选出了对PI4-K与抗体活性亲和力具有上调或下调作用的两种不同组分,提示在这二种组分里可能存在有不同的分子对PI4-K有着上调或下调的作用。结论从上述二种组分里有可能开发出治疗肿瘤和抗衰老的药物。这一筛选方法也可为今后的药物筛选提供一种新的思路。     

Pain and Effusion and Quadriceps Activation and Strength

Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

• Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
• The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
• To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.

Quadriceps weakness is a common consequence of traumatic knee joint injury^1,2 and chronic degenerative knee joint conditions.^3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.⁵ The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,⁶ biomechanical deficits,⁷ and possibly reinjury.⁵ Furthermore, researchers^8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,^10–12 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al^13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators¹⁵ have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,⁷ produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,^16–18 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.⁵ The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.¹⁹ Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.^16–18 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.²⁰ Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.     

即早基因c-fos与脑血管病及学习记忆

即早基因c-fos是广泛存在于原核细胞和真核细胞的高度保守基因.在正常情况下,c-fos基因参与细胞生长、分化、信息传递、学习和记忆等生理过程,而在病理情况下c-fos基因表达及调控变化与多种疾病的发生和发展有关.C-fos在中枢神经系统的某些部位可有基础水平的表达,但表达很低,当受到如脑缺血、脑出血、痫性发作、应激等刺激后,其在数十分钟内做出反应,在对外界刺激-转录耦联的信忠传递过程中起着核内第三信使的重要作用.     

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.