共表达人B7—1和HGF／NK4基因的重组腺病毒的制备及初步鉴定

目的构建能同时表达B7—1和HGF／NK4基因的重组腺病毒载体，同时制备相应的复制缺陷型重组腺病毒，检测其在喉癌细胞中的表达。方法构建以串联方式携带人B7-1和HGF／NK4基因的重组穿梭载体pAdtrack-NK4-B7-1。Pme I线性化后与腺病毒载体pAdEasy-1共转化大肠杆菌BJ5183，通过同源重组得到重组腺病毒载体pAd—NK4-B7—1。将重组腺病毒载体转染HEK293包装细胞制备重组腺病毒，应用病毒悬液感染人喉癌细胞株。用RT-PCR检测感染细胞中B7-1和NK4基因mRNA表达。结果酶切鉴定证实阳性pAdTrack—NK4-B7—1重组穿梭载体含有目的基因B7-1和HGF／NK4，同源重组后制备的病毒载体DNA经酶切鉴定获得了阳性重组腺病毒载体，该载体能有效转染HEK293细胞并在细胞内成功包装，转染3d后可以观察到绿色荧光蛋白（GFP）表达并逐渐增多、增强。制备的Ad—NK4-B7在体外能有效感染Hep-2细胞，感染后可维持6d高水平的B7—1和NK4基因的表达，整体表达可持续2周。结论成功构建了同时表达B7．1和NK4基因的重组腺病毒载体并制备出重组腺病毒颗粒，该病毒能有效地感染喉癌细胞并表达高水平的NK4和B7-1基因，为进一步研究B7—1和NK4基因的功能及应用B7—1和NK4进行喉癌的联合基因治疗提供了依据和素材。     

表达人B7-1的重组腺病毒的制备及初步鉴定

目的构建表达B7-1基因的重组腺病毒载体,制备相应的复制缺陷型重组腺病毒并检测其在喉癌细胞中的表达。方法构建携带人B7-1基因的重组穿梭载体pAdtrack-B7-1,PmeI线性化后与腺病毒载体pAdEasy-1共转化大肠杆菌BJ5183,通过同源重组得到重组腺病毒载体pAd-B7-1。将重组腺病毒载体转染HEK293包装细胞制备重组腺病毒,应用病毒悬液感染人喉癌细胞株,RT-PCR检测感染细胞中B7-1基因mRNA表达。结果酶切鉴定证实阳性pAdTrackB7-1重组穿梭载体含有目的基因B7-1,同源重组后制备的病毒载体DNA经酶切鉴定获得了阳性重组腺病毒载体,该载体能有效转染HEK293细胞并在细胞内成功包装,转染3d后可以观察到绿色荧光蛋白(GFP)表达并逐渐增多、增强。制备的Ad-B7在体外能有效感染Hep-2细胞,感染后可维持6d高水平的B7-1的表达,整体表达可持续两周。结论成功构建了同时表达B7-1的重组腺病毒载体并制备出重组腺病毒颗粒,该病毒能有效地感染喉癌细胞并表达高水平的B7-1基因,为进一步研究B7-1的功能及应用B7-1进行基因治疗奠定基础。     

重组人肝细胞生长因子-NK4腺病毒的制备及初步鉴定

目的 制备表达人肝细胞生长因子(HGF)-NK4蛋白的复制缺陷型重组腺病毒.方法 酶切pcDNA3-hNK4质粒获得NK4基因编码区序列并克隆至穿梭载体构建重组pAdTrack-CMV-NK4载体,线性化后与pAdEasy-1共转化BJ5183,通过同源重组得到重组pAd-NK4病毒载体.将重组腺病毒载体转染HEK293包装细胞制备重组腺病毒,用病毒悬液感染人肝癌细胞株HepG2.RT-PCR法检测感染肿瘤细胞中NK4 mRNA表达.结果 酶切鉴定得到阳性pAd-NK4重组腺病毒载体,该载体能有效转染HEK293细胞并在细胞内成功包装.在转染2d后能观察到绿色荧光蛋白(GFP)表达.制备的Ad- NK4在体外能有效感染HepG2细胞并获得NK4基因高水平表达.结论 成功构建了NK4基因的重组腺病毒载体并制备重组腺病毒颗粒,为进一步研究NK4基因的功能及应用NK4进行基因治疗提供实验依据.     

重组人肝细胞生长因子-NK4腺病毒的制备及初步鉴定

目的制备表达人肝细胞生长因子（HGF）-NK4蛋白的复制缺陷型重组腺病毒。方法酶切pcDNA3-hNK4质粒获得NK4基因编码区序列并克隆至穿梭载体构建重组pAdTrack—CMV—NK4载体，线性化后与pAdEasy-1共转化BJ5183，通过同源重组得到重组pAd—NK4病毒载体。将重组腺病毒载体转染HEK293包装细胞制备重组腺病毒，用病毒悬液感染人肝癌细胞株HepG2。RT—PCR法检测感染肿瘤细胞中NK4mRNA表达。结果酶切鉴定得到阳性pAd—NK4重组腺病毒载体，该载体能有效转染HEK293细胞并在细胞内成功包装。在转染2d后能观察到绿色荧光蛋白（GFP）表达。制备的Ad—NK4在体外能有效感染HepG2细胞并获得NK4基因高水平表达。结论成功构建了NK4基因的重组腺病毒载体并制备重组腺病毒颗粒，为进一步研究NK4基因的功能及应用NK4进行基因治疗提供实验依据。     

人胸腺基质淋巴生成素基因重组腺病毒载体的构建及表达

目的: 构建含人胸腺基质淋巴生成素基因(TSLP)的重组腺病毒载体并表达, 以研究其免疫学功能。方法: 将由人胚肺细胞扩增得到的TSLP基因, 克隆于真核表达载体pcDNA3. 1中, 再亚克隆至穿梭质粒pShuttle中, 并与腺病毒骨架载体pAdEasy -1共同转化大肠杆菌。以获得的重组质粒线性化后转染HEK293细胞, 并包装成病毒颗粒。采用PCR法对重组腺病毒基因进行鉴定, 并以Westernblot检测TSLP蛋白的表达。结果: 通过细菌内同源重组, 成功构建带有人胸腺基质淋巴生成素基因的重组腺病毒质粒, 转染 293细胞后, 包装的重组病毒经PCR检测表明, 基因组含有目的基因,病毒的滴度可达 1×1011pfu/L。Westernblot证实, 感染的肿瘤细胞中有相应基因产物的表达。结论: 通过菌内重组可高效制备带有特定基因的重组病毒。所制备的Ad -TSLP可成功表达相应基因产物, 为进一步研究这一新型细胞因子的功能奠定了基础。     

HAX1和EGFP共表达重组腺病毒载体的构建、鉴定

目的 构建和鉴定HAX1和EGFP双基因共表达重组腺病毒载体.方法 采用DNA重组技术,将目的 基因HAX1克隆至含有报告基因EGFP的穿梭质粒pAdTrack-CMV中,并转化于大肠埃希菌DH5α;筛选出重组质粒pAdTrack-CMV- HAX1,并在BJ5183细菌中与pAdEasy-1质粒进行同源重组,产生重组腺病毒载体;用lipofectamine将其转染HEK293细胞,包装携带全长HAX1的重组复制缺陷型腺病毒pAd-HAX1-EGFP,酶切和序列测定鉴定;用制备好的Ad-HAX1-EGFP感染HEK293细胞,流式细胞术检测其感染效率,RT-PCR、Western 印迹鉴定外源基因HAX1的表达.BrdU检测感染了Ad-HAX1-EGFP的HEK293细胞增殖情况.结果 pAdTrack-CMV-HAX1重组质粒构建成功.pAdTrack-CMV-HAX1 质粒与pAdEasy-1质粒同源重组后与预期结果相符.构建好的Ad-HAX1-EGFP能有效感染HEK293细胞;外源基因能在239细胞中有效表达.HAX1高表达的HEK293细胞其增殖率得以提高.结论 成功构建了表达HAX1和EGFP共表达的重组腺病毒载体,HAX1能够促进结肠癌细胞HEK293细胞的增殖.     

前凋亡因子bimS基因的重组腺病毒载体构建

为探讨前凋亡因子bimS用于肿瘤基因治疗奠定基础,拟构建bimS的重组腺病毒载体。采用RT-PCR方法从人HL-60细胞扩增目的基因bimS;克隆至T载体测序正确。亚克隆bimS基因到腺病毒穿梭质粒pAdtrack-CMV上,形成含目的基因和绿色荧光蛋白(GFP)基因的穿梭载体。穿梭载体pAdtrack-CMV-bimS和病毒骨架载体pAdEasy-1经电穿孔法转入BJ5183大肠杆菌中行同源重组,获得重组pAdEasy-CMV-bimS,线性化后脂质体法转染人胚肾(HEK)293细胞进行病毒的包装、扩增、病毒滴度测定以及瞬时表达的观察;将病毒以MOI=100感染HEK293细胞,western blot检测bimS蛋白表达。结果显示病毒感染293细胞48~72h观察到GFP表达,7d出现典型细胞病变症状(CPE);提取培养上清中病毒DNA,以PCR法可检测到bimS的扩增产物;western blot检测病毒感染的293细胞总蛋白,与未感染的阴性对照细胞相比,bimS蛋白表达明显高于阴性对照细胞。表明重组bimS腺病毒构建成功;为进一步进行肿瘤基因治疗的体内外试验奠定基础。     

大鼠GLUT1基因的扩增及其重组腺病毒载体的构建

目的:构建携带大鼠葡萄糖转运体1基因（GLUT1）的复制缺陷型重组腺病毒载体，为进一步研究脑缺血缺氧引起的神经元死亡机制奠定基础。方法:采用逆转录-聚合酶链反应（RT-PCR）的方法获取大鼠GLUT1基因全长cDNA，将其克隆至穿梭质粒pShuttle中构建穿梭质粒pShuttle-Glut1，经酶切后与线性化的腺病毒骨架质粒pAdeno-X体外连接并转化大肠杆菌DH5α，构建重组腺病毒质粒pAd-Glut1，酶切线性化重组腺病毒质粒后转染HEK293细胞包装成重组病毒颗粒，重组腺病毒在HEK293细胞中反复扩增数代后，分别用聚合酶链反应（PCR）及免疫印迹法（Western blotting）从基因和蛋白表达水平鉴定重组的腺病毒。结果:经PCR分析及DNA测序显示GLUT1 cDNA序列正确；筛选出重组腺病毒质粒pAd-Glut1后在HEK293细胞中成功包装出重组病毒，包装后冻融细胞行PCR及Western blotting检测表明重组腺病毒包装成功。结论:成功扩增了大鼠GLUT1基因并构建了携带大鼠GLUT1基因的复制缺陷型重组腺病毒载体，这有助于研究脑缺血缺氧引起的神经元死亡的机制。     

草原兔尾鼠卵透明带3基因重组腺病毒载体的构建及表达

目的:探索制备免疫不育疫苗的新途径,获得草原兔尾鼠卵透明带3(LZP3)重组腺病毒减毒活疫苗。方法:将LZP3基因亚克隆到穿梭质粒pShuttle-CMV上,采用细菌内同源重组"两步转化法"构建携带LZP3基因的重组腺病毒载体。获得的重组腺病毒载体线性化后转染HEK293细胞,包装成病毒颗粒。PCR鉴定重组腺病毒,继而用鉴定正确的重组腺病毒感染HeLa细胞,并以RT-PCR、Western blot检测LZP3的转录和表达。结果:成功构建了携带LZP3基因的重组腺病毒pAd-LZP3载体,其转染293细胞后包装出重组病毒,PCR证实LZP3基因已整合至腺病毒基因组中,病毒的滴度可达1.2×1010pfu/L。RT-PCR和Western blot检测表明RAd-LZP3感染的HeLa细胞中LZP3基因能够有效转录和表达。结论:制备的RAd-LZP3可成功表达LZP3基因,为后续开展RAd-LZP3免疫动物的研究奠定了基础。     

鼠A20基因的腺病毒载体构建及耳蜗毛细胞表达

目的 构建鼠锌指蛋白A20基因的重组腺病毒载体,并观察其对豚鼠耳蜗毛细胞的感染情况.方法 采用基因工程技术,经亚克隆后将A20基因片段克隆至穿梭质粒pAdTrack-CMV上,利用pAdEasy系统进行细菌内同源重组后,脂质体转染HEK293细胞包装、扩增,将重组腺病毒感染耳蜗毛细胞.PCR方法对重组体腺病毒进行鉴定,利用穿梭质粒中带有绿色荧光蛋白GFP报告基因对病毒滴度和感染情况进行监测.结果 酶切鉴定及PCR结果表明A20基因重组腺病毒载体构建成功,病毒滴度达5×109pfu/mL,并对耳蜗毛细胞有很强的感染能力.结论 应用细菌内同源重组法成功构建了含鼠A20基因的重组腺病毒载体.     

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.