染色体易位与恶性肿瘤

染色体易位是恶性肿瘤重要的分子遗传学改变之一,一方面,染色体易位可使原癌基因异常表达;另一方面,染色体易位使易位后相邻的基因融合,形成新的融合基因并表达相关产物,可导致细胞生长和分化等生物学行为的改变[1],特异的易位或易位基因产物可作为肿瘤特征性标志,检测这些标志有助于肿瘤的诊断,亦可预测肿瘤患者的预后.     

外周原始神经外胚叶瘤和尤因肉瘤染色体易位研究进展

染色体相互易位多见于骨和软组织肉瘤以及淋巴造血系统恶性肿瘤中．这些染色体易位导致多种分子水平上的异常．特别是融合基因的形成．被认为与肿瘤的发生有关。外周原始神经外胚叶瘤(peripheral primitive neuroectodermal tumors．pPNET)和尤因肉瘤(Ewing’s sarcoma．EWS)是软组织和骨常见的高度恶性肿瘤，两者关系密切，都有特征性     

腺泡型横纹肌肉瘤t(2;13)(q35;q14)和t(1;13)(p36;q14)染色体易位研究进展

RMS是儿童软组织肿瘤中最常见的一种恶性肿瘤。近年来 ,分子遗传学研究发现 ARMS有特异的 t(2 ;13) (q35 ;q14 )和 t(1;13) (p36 ;q14 )染色体易位 ,研究这两种易位有助于 ARMS的诊断和其分子发病机制的阐明。本文就 ARMS染色体易位方面的研究进展作一综述     

腺泡型模纹肌肉瘤t（2；13）（q35；q14）和t（1；13）（p36；q14）染色体易位研究进展

RMS是儿童软组织肿瘤中最常见的一种恶性肿瘤。近年来，分子遗传学研究发现ARMS有特异的t(2；13)(q35；q14)和t(1；13)(p36；q14)染色体易位，研究这两种易位有助于ARMS的诊断和其分子发病机制的阐明。本文就ARMS染色体易位方面的研究进展作一综述。     

bc1－2癌基因蛋白在滤泡性淋巴瘤中的过度表达

ｂｃ１－２癌基因蛋白在滤泡性淋巴瘤中的过度表达王洁，李甘地，赖仁胜，刘正明人类大部分造血系统恶性肿瘤均有特异性的染色体异常（主要是易位和插入）。在滤泡性淋巴瘤中，最常见的染色体异常是ｔ（１４：１８）。这一易位导致１４号染色体上免疫球蛋白重链基因（Ｉｇ...     

胚胎植入前遗传学诊断中Array CGH技术的应用

<正>染色体易位是常见的染色体结构异常,自然界中的物理、化学、生物等因素都可能使染色体发生断裂,当两条染色体同时发生断裂,其染色体的片段接合到另一条染色体上即形成易位,包括相互易位、罗伯逊易位和复杂易位等。这类易位大多数都保留了原有基因总数,对基因作用和个体发育一般无严重影响,故称平衡易位。由于易位一般没有遗传物质的增减,染色体易位携带者通常无表型异常,但在生殖细胞减数分裂过程中,可产生各种不平衡重     

二例罗伯逊易位的男性患者精液常规及精子形态学参数分析

罗伯逊易位在新生儿的出现率约为千分之二，也是最常见的人类染色体异常，这种核型只涉及人类核型中的D和G组染色体，在同源和／异源的端着丝粒染色体之问通过着丝粒融合或者着丝粒附近的断裂和重接丽形成的。大多数的罗伯逊易位包含两条非同源染色体，其中最常见的13q14q，其次是14q21q，他们的发生率分别占罗伯逊易位的73％和10％。     

无锡地区3869例遗传咨询者染色体核型的分析

目的为了降低出生缺陷，提高出生人口素质，探讨不良生育史和生长发育不良等情况与染色体异常的关系。方法对3869例遗传咨询者进行外周血染色体检查。结果共有249例染色体异常，阳性率为6．4％，易位和性染色体异常是最常见的染色体异常类型。结论染色体异常是造成生长发育异常、自然流产、不育不孕、月经不调、生育畸胎与智碍儿的重要原因之一。     

4520例生殖异常夫妇外周血染色体核型分析

目的探讨生殖异常夫妇的外周血染色体异常核型及其临床表现。方法回顾性分析2011年7月～2019年12月到河北省邯郸市中心医院检验科行外周血染色体核型分析的4520例生殖异常夫妇的外周血染色体G显带核型及其临床表现。结果 4520例行外周血染色体检查的生殖异常夫妇按临床表现分为不孕不育、流产死胎、异常儿生育史以及辅助生殖前检查四组,共检出染色体异常152例(152/4520,3.36%),包括性反转8例,均为不孕不育;染色体数目异常及其嵌合57例,以不孕不育最常见;染色体结构异常87例(包括染色体相互易位39例,罗氏易位16例,倒位27例,缺失2例,等臂染色体3例),以流产死胎最常见。不孕不育、流产死胎、异常儿生育史以及辅助生殖前检查组染色体异常检出率分别为4.09%、3.29%、2.38%、2.46%。结论染色体异常是导致夫妇生殖异常的重要原因之一。生殖异常包括欲行辅助生殖夫妇,建议其行外周血染色体核型分析和遗传咨询,有助于明确病因并及时选取合理的治疗措施。     

滨州地区染色体罗伯逊易位与不良孕产史

人类染色体结构异常是引起自然流产、死胎、畸形儿的重要原因之一,而罗伯逊易位又是常见的染色体结构异常,又称着丝粒融和,是相互易位的一种特殊形式,易位发生在D组和G组染色体之间,发病率1‰.我们对在临床上检出的19例罗伯逊易位携带者的遗传效应进行了分析和总结.报告如下.     

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.