• 【静止T细胞的有丝分裂刺激导致转录因子LSF迅速磷酸化,并增加了DNA结合活性。】 复制标题 收藏 收藏
    DOI:10.1101/gad.11.11.1435 复制DOI
    作者列表:Volker JL,Rameh LE,Zhu Q,DeCaprio J,Hansen U
    BACKGROUND & AIMS: The mammalian transcription factor LSF (CP2/LBP-1c) binds cellular promoters modulated by cell growth signals. We demonstrate here that LSF-DNA-binding activity is strikingly regulated by induction of cell growth in human peripheral T lymphocytes. Within 15 min of mitogenic stimulation of these cells, the level of LSF-DNA-binding activity increased by a factor of five. The level of LSF protein in the nucleus remained constant throughout this interval. However, a rapid decrease in the electrophoretic mobility of LSF, attributable to phosphorylation, correlated with the increase in DNA-binding activity. pp44 (ERK1) phosphorylated LSF in vitro on the same residue that was phosphorylated in vivo, specifically at amino acid position 291, as indicated by mutant analysis. As direct verification of the causal relationship between phosphorylation and DNA-binding activity, treatment in vitro of LSF with phosphatase both increased the electrophoretic mobility of the protein and decreased LSF-DNA-binding activity. This modulation of LSF-DNA-binding activity as T cells progress from a resting to a replicating state reveals that LSF activity is regulated during cell growth and suggests that LSF regulates growth-responsive promoters.

    背景与目标: 哺乳动物转录因子LSF(CP2 / LBP-1c)结合受细胞生长信号调节的细胞启动子。我们在这里证明,LSF-DNA结合活性是由人类外周血T淋巴细胞的细胞生长诱导来显着调节的。在这些细胞的促有丝分裂刺激的15分钟内,LSF-DNA结合活性的水平提高了五倍。在整个间隔期间,核中LSF蛋白的水平保持恒定。但是,可归因于磷酸化的LSF电泳迁移率的快速下降与DNA结合活性的增加有关。突变分析表明,pp44(ERK1)在体外磷酸化的同一残基上,特别是在氨基酸位置291处磷酸化LSF。作为磷酸化与DNA结合活性之间因果关系的直接验证,体外用磷酸酶处理LSF既增加了蛋白质的电泳迁移率,又降低了LSF-DNA结合活性。当T细胞从静止状态发展到复制状态时,对LSF-DNA结合活性的这种调节揭示了LSF活性在细胞生长过程中受到调节,并暗示LSF调节生长响应性启动子。

  • 【凋亡的血管平滑肌细胞产生凝血酶。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Flynn PD,Byrne CD,Baglin TP,Weissberg PL,Bennett MR
    BACKGROUND & AIMS: Thrombin activation requires assembly of a prothrombinase complex of activated coagulation factors on an anionic phospholipid surface, classically provided by activated platelets. We have previously shown that anionic phosphatidylserine is exposed by rat vascular smooth muscle cells (VSMCs) undergoing apoptosis after serum withdrawal. In this study, using a chromogenic assay, we have shown thrombin generation by apoptotic VSMCs expressing c-myc (VSMC-myc) with an area under the thrombin-generation curve (AUC) of 305 +/- 17 nmol x min/L and a peak thrombin (PT) of 154 +/- 9 nmol/L. The thrombin-generating potential of the apoptotic VSMC-myc cells was greater than that of unactivated platelets (P = .003 for AUC; P = .0002 for PT) and similar to calcium-ionophore activated platelets (AUC of 332 +/- 15 nmol x min/L, P = .3; PT of 172 +/- 8 nmol/L, P = .2). Thrombin activation was also seen with apoptotic human VSMCs (AUC of 211 +/- 8 nmol x min/L; PT of 103 +/- 4 nmol/L) and was inhibited by annexin V (P < .0001 for AUC and PT). VSMC-myc cells maintained in serum generated less thrombin than after serum withdrawal (P = .0002 for AUC and PT). VSMCs derived from human coronary atherosclerotic plaques that apoptose even in serum also generated thrombin (AUC of 260 +/- 2 nmol x min/L; PT of 128 +/- 4 nmol/L). We conclude that apoptotic VSMCs possess a significant thrombin-generating capacity secondary to phosphatidylserine exposure. Apoptotic cells within atherosclerotic plaques may allow local thrombin activation, thereby contributing to disease progression.

    背景与目标: 凝血酶的活化需要活化的凝血因子的凝血酶原酶复合物在阴离子磷脂表面上的组装,这通常是由活化的血小板提供的。先前我们已经表明,在撤离血清后,发生凋亡的大鼠血管平滑肌细胞(VSMC)会暴露出阴离子磷脂酰丝氨酸。在这项研究中,我们使用发色试验显示了表达c-myc(VSMC-myc)的凋亡VSMC的凝血酶生成,其凝血酶生成曲线(AUC)下方的面积为305 /-17 nmol x min / L,凝血酶峰值(PT)为154 9 nmol / L。凋亡的VSMC-myc细胞的凝血酶生成潜能大于未激活的血小板(对于AUC,P = .003;对于PT,P = .0002),类似于钙离子载体激活的血小板(AUC为332 /-15 nmol) xmin / L,P = 0.3; PT为172 / 8-nmol / L,P = 0.2)。在凋亡的人VSMC中也观察到凝血酶活化(AUC为211 /-8 nmol x min / L; PT为103 /-4 nmol / L),并被膜联蛋白V抑制(对于AUC和PT,P <.0001)。血清中维持的VSMC-myc细胞产生的凝血酶少于血清中止后产生的凝血酶(对于AUC和PT,P = .0002)。源自甚至在血清中也会凋亡的人冠状动脉粥样硬化斑块的VSMC也会产生凝血酶(AUC为260 /-2 nmol x min / L; PT为128 /-4 nmol / L)。我们得出结论,凋亡性VSMC具有继磷脂酰丝氨酸暴露后的显着凝血酶生成能力。动脉粥样硬化斑块中的凋亡细胞可能允许局部凝血酶活化,从而促进疾病进展。

  • 【使用源自人脐带血的干细胞的潜在临床应用。】 复制标题 收藏 收藏
    DOI:10.1016/s1472-6483(10)60646-3 复制DOI
    作者列表:Ghen MJ,Roshan R,Roshan RO,Blyweiss DJ,Corso N,Khalili B,Zenga WT
    BACKGROUND & AIMS: :There is an abundance of clinical applications using human umbilical cord blood (HUCB) as a source for stem cell populations. Other than haematopoietic progenitors, there are mesenchymal, endothelial stem cells and neuronal precursors, in varying quantities, that are found in human umbilical cord blood. These may be useful in diseases such as immune deficiency and autoimmune disorders. Considering issues of safety, availability, transplant methodology, rejection and side effects, it is contended that a therapeutic stem cell transplant, utilizing stem cells from HUCB, provides a reliable repository of early precursor cells that can be useful in a great number of diverse conditions. Drawbacks of relatively smaller quantities of mononucleated cells in one unit of cord blood can be mitigated by in-vitro expansion procedures, improved in-vivo signalling, and augmentation of the cellular milieu, while simultaneously choosing the appropriate transplantation site and technique for introduction of the stem cell graft.
    背景与目标: :有大量的临床应用使用人类脐带血(HUCB)作为干细胞群体的来源。除造血祖细胞外,人类脐带血中还存在不同数量的间充质,内皮干细胞和神经元前体。这些可能对诸如免疫缺陷和自身免疫性疾病等疾病有用。考虑到安全性,可用性,移植方法,排斥反应和副作用等问题,可以认为,利用HUCB干细胞进行的治疗性干细胞移植可提供可靠的早期前体细胞库,该库可用于多种条件。可以通过体外扩增程序,改进的体内信号传导和细胞环境增强来缓解一单位脐带血中相对较少数量的单核细胞的缺点,同时选择合适的移植部位和技术引入干细胞移植。
  • 【拉坦前列素对人小梁网细胞中基质金属蛋白酶及其组织抑制剂表达的影响。】 复制标题 收藏 收藏
    DOI:10.1167/iovs.06-0036 复制DOI
    作者列表:Oh DJ,Martin JL,Williams AJ,Russell P,Birk DE,Rhee DJ
    BACKGROUND & AIMS: PURPOSE:To determine the effect of latanoprost on the expression of human matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in the trabecular meshwork (TM). METHODS:Total RNA was isolated, and qualitative RT-PCR was performed to detect the mRNA of MMPs and TIMPs in human TM tissue and explant cultures of TM endothelial cells. Cultures of TM cells were treated with vehicle control or latanoprost acid for 24 hours. Real-time RT-PCR of cell cultures from five different donors was performed to determine relative changes in expression. GAPDH served as an endogenous control. RESULTS:The mRNA of MMP-1, -2, -3, -11, -12, -14, -15, -16, -17, -19, and -24 and of TIMP-1 to -4 was present in TM tissue and cultures of TM cells. MMP-9 was not found. In control TM endothelial cells, the relative expression of MMP mRNA were MMP-2 and -14 > MMP-16, -19, and -24 > MMP-15 > MMP-11 and -17 > MMP-1 and -3 > MMP-12. The relative expressions of TIMP mRNA were TIMP-1 > TIMP-2 and -3 > TIMP-4. Latanoprost increased MMP-1 (in four of five cultures), MMP-3 (in four of five cultures), MMP-17 (in three of five cultures), MMP-24 (in all five cultures), TIMP-2, -3, and -4 expression (in three of five cultures); MMP-11 and -15 were downregulated. CONCLUSIONS:Contrary to the expected result, latanoprost seems to have a significant effect on TM cells. The transcription of the genes for MMP-1, -3, -17, and -24 is increased by latanoprost treatment. TIMP-2, -3, and -4 are also upregulated. The upregulation of these TIMPs may compensate for the increase of those MMPs. The absence of MMP-9 and concurrent upregulation of a greater number of TIMPs may explain the limited effect of latanoprost on TM outflow.
    背景与目标: 目的:确定拉坦前列素对小梁网(TM)中人基质金属蛋白酶(MMPs)和金属蛋白酶组织抑制剂(TIMPs)表达的影响。
    方法:分离总RNA,进行定性RT-PCR检测人TM组织和TM内皮细胞外植体培养物中MMP和TIMP的mRNA。用媒介物对照或拉坦前列素酸处理TM细胞的培养物24小时。对来自五个不同供体的细胞培养物进行了实时RT-PCR,以确定表达的相对变化。 GAPDH用作内源性对照。
    结果:MMP-1,-2,-3,-11,-12,-14,-15,-16,-17,-19和-24和TIMP-1至-4的mRNA均存在于TM组织和TM细胞培养物。找不到MMP-9。在对照TM内皮细胞中,MMP mRNA的相对表达为MMP-2和-14> MMP-16,-19和-24> MMP-15> MMP-11和-17> MMP-1和-3> MMP -12。 TIMP mRNA的相对表达为TIMP-1> TIMP-2和-3> TIMP-4。拉坦前列素可提高MMP-1(在五种文化中的四种),MMP-3(在五种文化中的四种),MMP-17(在五种文化中的三种),MMP-24(在五种文化中),TIMP-2,- 3和-4表达(在五种文化中的三种); MMP-11和-15下调。
    结论:与预期结果相反,拉坦前列素似乎对TM细胞有显着影响。拉坦前列素处理可增加MMP-1,-3,-17和-24基因的转录。 TIMP-2,-3和-4也被上调。这些TIMP的上调可以补偿那些MMP的增加。 MMP-9的缺乏和大量TIMP的同时上调可能解释了拉坦前列素对TM外流的作用有限。
  • 【耳蜗边缘细胞和前庭暗细胞进行矢量钾转运的计算模型。】 复制标题 收藏 收藏
    DOI:10.1152/ajpcell.00560.2005 复制DOI
    作者列表:Quraishi IH,Raphael RM
    BACKGROUND & AIMS: :Cochlear marginal cells and vestibular dark cells transport potassium into the inner ear endolymph, a potassium-rich fluid, the homeostasis of which is essential for hearing and balance. We have formulated an integrated mathematical model of ion transport across these epithelia that incorporates the biophysical properties of the major ion transporters and channels located in the apical and basolateral membranes of the constituent cells. The model is constructed for both open- and short-circuit situations to test the extremes of functional capacity of the epithelium and predicts the steady-state voltages, ion concentrations, and transepithelial currents as a function of various transporter and channel densities. We validate the model by establishing that the cells are capable of vectorial ion transport consistent with several experimental measurements. The model indicates that cochlear marginal cells do not make a significant direct contribution to the endocochlear potential and illustrates how changes to the activity of specific transport proteins lead to reduced K(+) flux across the marginal and dark cell layers. In particular, we investigate the mechanisms of loop diuretic ototoxicity and diseases with hearing loss in which K(+) and Cl(-) transport are compromised, such as Jervell and Lange-Nielsen syndrome and Bartter syndrome, type IV, respectively. Such simulations demonstrate the utility of compartmental modeling in investigating the role of ion homeostasis in inner ear physiology and pathology.
    背景与目标: :耳蜗边缘细胞和前庭暗细胞将钾转运到内耳内淋巴,这是一种富含钾的液体,其稳态对听力和平衡至关重要。我们已经制定了一个跨这些上皮细胞的离子迁移的综合数学模型,该模型整合了主要离子转运蛋白和位于组成细胞顶膜和基底外侧膜中的通道的生物物理特性。该模型适用于开路和短路情况,以测试上皮的功能极限,并预测稳态电压,离子浓度和跨上皮电流随各种转运蛋白和通道密度的变化。我们通过建立细胞能够进行矢量离子运输与几个实验测量结果一致的方法来验证模型。该模型表明,耳蜗边缘细胞对内耳蜗电位没有显着直接贡献,并说明了特定转运蛋白活性的变化如何导致跨边缘和黑暗细胞层的K()通量降低。特别是,我们研究了of利尿剂的耳毒性和机制,其中K()和Cl(-)的运输受到损害的听力损失的疾病,例如分别为IV型Jervell和Lange-Nielsen综合征和Bartter综合征。这样的模拟证明了隔室模型在研究离子稳态在内耳生理和病理中的作用方面的实用性。
  • 6 Mast cells in surgically resected appendices. 复制标题 收藏 收藏

    【手术切除的阑尾中的肥大细胞。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Mysorekar VV,Chanda S,Dandeka CP
    BACKGROUND & AIMS: :Mast cells are known to be effector cells in various inflammatory reactions, but their role in appendicitis is unclear. The present study was undertaken to investigate the extent of mast cell involvement in appendicitis and evaluate their possible role. A total of 150 appendices including normal and inflamed appendices, were assessed for their histological changes and density of neutrophil, lymphocyte and eosinophil infiltration. The mast cells were counted in 1% toluidine blue-stained sections. It was found that eosinophil counts in all the layers were significantly low in normal appendices (P<0.01) and in chronic appendicitis (P<0.1) as compared to acute appendicitis. Mast cell counts were lowest in normal appendices, significantly higher in acute appendicitis (P<0.01) and highest in chronic appendicitis (P<0.001). Obstruction due to faecoliths or parasites were seen in only 20.1% and 2.1% of the inflamed appendices respectively. Hence a Type I hypersensitivity reaction with release of mediators by mast cells might be another triggering factor for the sequence of events leading to appendicitis.
    背景与目标: :已知肥大细胞是各种炎症反应中的效应细胞,但它们在阑尾炎中的作用尚不清楚。本研究旨在研究肥大细胞参与阑尾炎的程度并评估其可能的作用。共评估了150个阑尾,包括正常和发炎的阑尾的组织学变化以及中性粒细胞,淋巴细胞和嗜酸性粒细胞浸润的密度。肥大细胞在1%甲苯胺蓝染色的切片中计数。发现与急性阑尾炎相比,正常阑尾(P <0.01)和慢性阑尾炎(P <0.1)所有层的嗜酸性粒细胞计数均显着较低。正常阑尾中的肥大细胞计数最低,急性阑尾炎中的肥大细胞计数显着更高(P <0.01),而慢性阑尾炎中的肥大细胞计数最高(P <0.001)。分别在发炎的阑尾中仅见20.1%和2.1%的因粪便或寄生虫引起的阻塞。因此,肥大细胞释放介体的I型超敏反应可能是导致阑尾炎的一系列事件的另一个触发因素。
  • 【刺猬组织果蝇腹部表皮细胞的模式和极性。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Struhl G,Barbash DA,Lawrence PA
    BACKGROUND & AIMS: The abdomen of adult Drosophila, like that of other insects, is formed by a continuous epithelium spanning several segments. Each segment is subdivided into an anterior (A) and posterior (P) compartment, distinguished by activity of the selector gene engrailed (en) in P but not A compartment cells. Here we provide evidence that Hedgehog (Hh), a protein secreted by P compartment cells, spreads into each A compartment across the anterior and the posterior boundaries to form opposing concentration gradients that organize cell pattern and polarity. We find that anteriorly and posteriorly situated cells within the A compartment respond in distinct ways to Hhthey express different combinations of genes and form different cell types. They also form polarised structures that, in the anterior part, point down the Hh gradient and, in the posterior part, point up the gradient - therefore all structures point posteriorly. Finally, we show that ectopic Hh can induce cells in the middle of each A compartment to activate en. Where this happens, A compartment cells are transformed into an ectopic P compartment and reorganise pattern and polarity both within and around the transformed tissue. Many of these results are unexpected and lead us to reassess the role of gradients and compartments in patterning insect segments.

    背景与目标: 像其他昆虫一样,成年果蝇的腹部由跨越几个部分的连续上皮形成。每个部分细分为前(A)和后(P)隔室,其区别在于P(A)中夹带(en)而不是A隔室细胞的选择基因的活性。在这里,我们提供的证据表明,刺猬(Hh)是P隔室细胞分泌的一种蛋白质,它通过前后边界扩散到每个A隔室中,从而形成组织细胞模式和极性的相对浓度梯度。我们发现A区隔中的前向和后向细胞以不同的方式对Hhthey​​表达不同的基因组合并形成不同的细胞类型作出反应。它们还形成极化结构,该结构在前部指向Hh梯度,而在后部指向Hh梯度-因此所有结构都向后指向。最后,我们表明异位Hh可以诱导每个A区中间的细胞激活en。在发生这种情况的地方,A隔室细胞被转化为异位P隔室,并在转化组织内部和周围重新组织模式和极性。这些结果中有许多是出乎意料的,使我们重新评估了梯度和区室在图案化昆虫片段中的作用。

  • 【雌二醇通过上调Fas和Fas配体表达来增加人冠状动脉内皮细胞的凋亡。】 复制标题 收藏 收藏
    DOI:10.1210/jc.2006-1225 复制DOI
    作者列表:Seli E,Guzeloglu-Kayisli O,Cakmak H,Kayisli UA,Selam B,Arici A
    BACKGROUND & AIMS: CONTEXT:In animal models, estrogen inhibits atherogenesis by inhibiting many of the early steps of atherosclerotic plaque formation. However, the lack of cardioprotective effect by postmenopausal hormone replacement therapy and possible increase in cardiovascular events observed during the first year after the initiation of hormone replacement therapy may suggest that once the plaque is formed, estrogen may have additional effects that may counteract its beneficial outcomes. Indeed, the effect of estrogen on plaque stability has not been identified. OBJECTIVE:We hypothesized that 17beta-estradiol (E2) may cause increased apoptosis in human coronary artery endothelial cells (HCAECs). This effect would explain an adverse effect on plaque stability in vivo. INTERVENTION(S) AND MAIN OUTCOME MEASURE(S):The effect of E2 on apoptosis, cell proliferation, and expression of proapoptotic molecules Fas and Fas ligand (FasL) in cultured HCAECs was evaluated. RESULTS:HCAECs in culture treated with E2 showed an increase in DNA strand breaks and nuclear fragmentation indicative of apoptosis. E2 treatment also induced a significant concentration-dependent increase in Fas mRNA and protein expressions in HCAECs. Moreover, the expression of FasL mRNA and secretion of FasL protein by HCAECs were enhanced in response to E2 treatments. CONCLUSIONS:E2 increases the apoptosis in cultured HCAECs. Enhanced Fas and FasL expressions in response to E2 suggest that activation of the Fas/FasL pathway may be a mediator of the proapoptotic effects of E2 in these cells.
    背景与目标: 背景:在动物模型中,雌激素通过抑制动脉粥样硬化斑块形成的许多早期步骤来抑制动脉粥样硬化。但是,绝经后激素替代疗法缺乏心脏保护作用,并且在开始激素替代疗法后的第一年内观察到的心血管事件可能增加,这表明一旦形成斑块,雌激素可能会产生额外的作用,从而抵消其有益结果。实际上,尚未确定雌激素对斑块稳定性的作用。
    目的:我们假设17β-雌二醇(E2)可能导致人冠状动脉内皮细胞(HCAEC)凋亡增加。该作用将解释对体内斑块稳定性的不利影响。
    干预和主要观察指标:评估了E2对培养的HCAEC中细胞凋亡,细胞增殖以及促凋亡分子Fas和FasL配体(FasL)表达的影响。
    结果:用E2处理的培养物中的HCAECs显示DNA链断裂的增加和核碎裂指示凋亡。 E2处理还诱导了HCAECs Fas mRNA和蛋白表达的浓度依赖性显着增加。而且,响应于E2处理,HCAECs的FasL mRNA的表达和FasL蛋白的分泌得到增强。
    结论:E2增加了培养的HCAECs的细胞凋亡。响应E2增强的Fas和FasL表达表明Fas / FasL途径的激活可能是这些细胞中E2促凋亡作用的介质。
  • 【白介素-1对大鼠培养的Ito细胞的松弛作用。】 复制标题 收藏 收藏
    DOI:10.1002/hep.510250618 复制DOI
    作者列表:Sakamoto M,Ueno T,Sugawara H,Torimura T,Tsuji R,Sujaku K,Sata M,Tanikawa K
    BACKGROUND & AIMS: Interleukin-1beta (IL-1beta) is closely involved in liver disorders. IL-1beta produces nitric oxide (NO) in vascular smooth muscle cells and relaxes vascular smooth muscle via cyclic guanosine 3',5'-monophosphate (cGMP). In this study, we evaluated the relaxing effect of IL-1beta on cultured Ito cells. Ito cells were isolated from the livers of male Wistar rats and cultured for 24 hours. Immunolocalization of inducible nitric oxide synthase (iNOS) and cGMP and intensity of fluorescence of cGMP were examined using a confocal laser microscope. Ito cells were treated with 0, 200, and 1,000 pmol/L IL-1beta, and the intracellular cGMP concentration was measured after 12 hours. Moreover, Ito cells treated with 200 and 1,000 pmol/L IL-1beta and not treated with IL-1beta were observed over 12 hours, and the area of the same Ito cell was compared before and after the addition of IL-1beta. Next, effects of N(G)-monomethyl-L-arginine (L-NMMA) and S-nitroso-N-acetyl-DL-penicillamine (SNAP) on Ito cell relaxation by IL-1beta treatment were examined. In Ito cells, immunofluorescence of iNOS was observed, and fluorescent intensity of cGMP increased after addition of IL-1beta. Intracellular cGMP concentration increased dose-dependently after addition of IL-1beta. Cell area significantly increased in the IL-1beta-treated group compared with the untreated group. Relaxation of Ito cells by IL-1beta treatment was inhibited by L-NMMA in a dose-dependent manner, but was enhanced by SNAP. These results indicate that IL-1beta produces NO in cultured Ito cells and relaxes the cells via cGMP.

    背景与目标: 白介素-1β(IL-1beta)与肝脏疾病密切相关。 IL-1β在血管平滑肌细胞中产生一氧化氮(NO),并通过环状鸟苷3',5'-单磷酸(cGMP)松弛血管平滑肌。在这项研究中,我们评估了IL-1β对培养的Ito细胞的松弛作用。从雄性Wistar大鼠的肝脏中分离出Ito细胞,并培养24小时。使用共聚焦激光显微镜检查诱导型一氧化氮合酶(iNOS)和cGMP的免疫定位和cGMP的荧光强度。用0、200和1,000 pmol / L IL-1beta处理Ito细胞,并在12小时后测量细胞内cGMP浓度。此外,在12小时内观察到用200和1,000 pmol / L IL-1beta处理且未用IL-1beta处理的Ito细胞,并且在添加IL-1beta之前和之后比较了同一个Ito细胞的面积。接下来,研究了N(G)-单甲基-L-精氨酸(L-NMMA)和S-亚硝基-N-乙酰基-DL-青霉胺(SNAP)对通过IL-1beta处理的Ito细胞松弛的影响。在Ito细胞中,观察到iNOS的免疫荧光,添加IL-1β后cGMP的荧光强度增加。加入IL-1beta后,细胞内cGMP浓度呈剂量依赖性增加。与未治疗组相比,IL-1β治疗组的细胞面积显着增加。 L-1NMMA以剂量依赖的方式抑制了通过IL-1beta处理的Ito细胞的松弛,但被SNAP增强了。这些结果表明IL-1β在培养的Ito细胞中产生NO,并通过cGMP使细胞松弛。

  • 【镉通过一系列引起细胞毒性的三波活性氧来影响烟草细胞。】 复制标题 收藏 收藏
    DOI:10.1111/j.1365-3040.2006.01571.x 复制DOI
    作者列表:Garnier L,Simon-Plas F,Thuleau P,Agnel JP,Blein JP,Ranjeva R,Montillet JL
    BACKGROUND & AIMS: :Cadmium is suspected to exert its toxic action on cells through oxidative damage. However, the transition metal is unable to directly generate reactive oxygen species (ROS) via redox reactions with molecular oxygen in a biological environment. Here, we show that bright yellow-2 (BY-2) tobacco cells exposed to millimolar concentrations of CdCl(2) developed cell death within 2-3 h. The death process was preceded by two successive waves of ROS differing in their nature and subcellular localization. Firstly, these consisted in the transient NADPH oxidase-dependent accumulation of H(2)O(2) followed by the accumulation of O(2) (-*) in mitochondria. A third wave of ROS consisting in fatty acid hydroperoxide accumulation was concomitant with cell death. Accumulation of H(2)O(2) was preceded by an increase in cytosolic free calcium concentration originating from internal pools that was essential to activate the NADPH oxidase. The cell line gp3, impaired in NADPH oxidase activity, and that was unable to accumulate H(2)O(2) in response to Cd(2+), was nevertheless poisoned by the metal. Therefore, this first wave of ROS was not sufficient to trigger all the cadmium-dependent deleterious effects. However, we show that the accumulation of O(2) (-*) of mitochondrial origin and membrane peroxidation are key players in Cd(2+)-induced cell death.
    背景与目标: :镉被怀疑通过氧化损伤对细胞产生毒性作用。然而,在生物环境中,过渡金属不能通过与分子氧的氧化还原反应直接产生活性氧(ROS)。在这里,我们显示暴露于毫摩尔浓度的CdCl(2)的亮黄色2(BY-2)烟草细胞在2-3小时内发展出细胞死亡。死亡过程之前是连续两次的ROS,其性质和亚细胞定位各不相同。首先,这些包括线粒体中H(2)O(2)的瞬时NADPH氧化酶依赖性积累,然后是线粒体中O(2)(-*)的积累。 ROS的第三波涉及脂肪酸氢过氧化物的积累,并伴随着细胞死亡。 H(2)O(2)的积累之前是来自内部池的胞质游离钙浓度的增加,这对于激活NADPH氧化酶是必不可少的。然而,细胞系gp3在NADPH氧化酶活性中受损,并且无法响应Cd(2)积聚H(2)O(2),但仍被金属中毒。因此,ROS的第一波不足以触发所有依赖镉的有害作用。但是,我们表明,线粒体起源的O(2)(-*)积累和膜过氧化是Cd(2)诱导的细胞死亡的关键因素。
  • 【通过过继转移CD4抗肿瘤T细胞杀死原位大鼠腺癌13762需要细胞表面MHC II类分子的肿瘤表达。】 复制标题 收藏 收藏
    DOI:10.1006/cimm.1997.1122 复制DOI
    作者列表:Frey AB,Cestari S
    BACKGROUND & AIMS: CD4+ anti-tumor T cells reactive with rat adenocarcinoma 13762 kill tumor in vitro and cause regression of tumor in vivo. The role of various host immune cells in CD4+ T-cell-mediated tumor elimination in vivo was investigated by adoptive transfer of anti-tumor T cell clones to recipients that were selectively depleted of individual immune cell types. By these means, macrophages and NK cells were found to be required for tumor killing. Depletion of host CD4+ T cells, CD8+ T cells, or neutrophils was without effect on tumor elimination by anti-tumor T cells. An essential role for antigen receptor-negative NK cells is likely dependent upon secretion of IFN-gamma from NK cells since treatment of tumor recipients with anti-IFN-gamma antibody prior to adoptive transfer and tumor challenge abrogated T cell killing, resulting in progressive tumor growth. Viability of adenocarcinoma 13762 or anti-tumor T cells was unaffected by treatment with either IFN-gamma or anti-IFN-gamma antibody in vitro, but cell surface MHC class II expression was induced in tumor cells by exposure to IFN-gamma. In addition, tumor cells were isolated from tumor-bearing animals by absorption using anti-MHC class II antibody, demonstrating that 13762 tumor expresses cell surface MHC class II antigens in situ. However, if hosts were depleted of NK cells before tumor challenge, MHC class II+ tumor was not recovered. Collectively these results suggest that adenocarcinoma 13762 is eliminated by MHC class II-restricted CD4+ T cells by direct tumor killing.

    背景与目标: 与大鼠腺癌13762反应的CD4抗肿瘤T细胞在体外杀死肿瘤并在体内引起肿瘤消退。通过将抗肿瘤T细胞克隆过继转移到选择性清除了个体免疫细胞类型的受体上,研究了各种宿主免疫细胞在体内CD4 T细胞介导的肿瘤消除中的作用。通过这些手段,发现杀死肿瘤需要巨噬细胞和NK细胞。宿主CD4 T细胞,CD8 T细胞或嗜中性白细胞的耗竭对抗肿瘤T细胞对肿瘤的消除没有影响。抗原受体阴性NK细胞的重要作用可能取决于NK细胞分泌IFN-γ,因为在过继转移和肿瘤攻击之前用抗IFN-γ抗体治疗肿瘤受体可以消除T细胞杀伤,从而导致进行性肿瘤生长。体外用IFN-γ或抗IFN-γ抗体治疗不会影响腺癌13762或抗肿瘤T细胞的存活率,但通过暴露于IFN-γ诱导了肿瘤细胞的细胞表面MHC II类表达。另外,通过使用抗MHC II类抗体的吸收从荷瘤动物中分离出肿瘤细胞,表明13762肿瘤原位表达细胞表面MHC II类抗原。但是,如果宿主在肿瘤攻击前已耗尽NK细胞,则无法恢复MHC II类肿瘤。这些结果共同表明,通过直接杀死肿瘤,MHC II类限制性CD4 T细胞可消除13762腺癌。

  • 【垂体激素调节胸腺细胞和胸腺上皮细胞之间的细胞间相互作用。】 复制标题 收藏 收藏
    DOI:10.1016/s0165-5728(97)00031-3 复制DOI
    作者列表:de Mello-Coelho V,Villa-Verde DM,Dardenne M,Savino W
    BACKGROUND & AIMS: The thymic microenvironment plays a key role in the intrathymic T-cell differentiation. It is composed of a tridimensional network of epithelial cells whose physiology is controlled by extrinsic circuits such as neuroendocrine axes. Herein we show that the expression of extracellular matrix ligands and receptor by cultured thymic epithelial cells is upregulated by prolactin (PRL) and growth hormone (GH), the latter apparently occurring via insulin-like growth factor I (IGF-I). Thymocyte release from the lymphoepithelial complexes, thymic nurse cells, as well as the reconstitution of these complexes are enhanced by PRL, GH or IGF-I. Treatment of a mouse thymic epithelial cell line with these hormones induced an increase in thymocyte adhesion, an effect significantly prevented in the presence of antibodies to fibronectin, laminin or respective receptors VLA-5 and VLA-6. Our data suggest that the in vitro changes in thymocyte/thymic epithelial cell interactions induced by pituitary hormones are partially mediated by the enhancement of extracellular matrix ligands and receptors.

    背景与目标: 胸腺微环境在胸腺内T细胞分化中起关键作用。它由上皮细胞的三维网络组成,其上皮细胞的生理受到外在回路(如神经内分泌轴)的控制。本文中我们显示,培养的胸腺上皮细胞的细胞外基质配体和受体的表达被催乳素(PRL)和生长激素(GH)上调,后者显然是通过胰岛素样生长因子I(IGF-1)发生的。 PRL,GH或IGF-I增强了从淋巴上皮复合物,胸腺护士细胞释放胸腺细胞以及这些复合物的重构。用这些激素处理小鼠胸腺上皮细胞系可诱导胸腺细胞粘附增加,在存在针对纤连蛋白,层粘连蛋白或相应受体VLA-5和VLA-6的抗体的情况下,该作用被显着阻止。我们的数据表明,垂体激素诱导的胸腺细胞/胸腺上皮细胞相互作用的体外变化部分由细胞外基质配体和受体的增强介导。

  • 【创伤弧菌溶血素对大鼠腹腔肥大细胞的细胞溶解作用。】 复制标题 收藏 收藏
    DOI:10.1099/00222615-32-1-39 复制DOI
    作者列表:Yamanaka H,Sugiyama K,Furuta H,Miyoshi S,Shinoda S
    BACKGROUND & AIMS: :The mode of action of Vibrio vulnificus haemolysin (VVH) on mast cells from the peritoneal cavity of the rat was examined. VVH induced histamine release, and damage to the mast cells, in a dose-dependent fashion. When 1 microgram of VVH was added to c. 10(5) mast cells at 37 degrees C, histamine release was observed after a lag period of 5-10 s, and was complete within 5 min. The action was temperature-dependent, and was not induced at 4 degrees C. Disodium cromoglycate, a membrane stabiliser for mast cells, inhibited the histamine release significantly, but the effect was not dose-dependent. Moreover, leakage of lactate dehydrogenase from VVH-treated mast cells was observed. These results suggest that VVH acts on the cell membrane of mast cells and is cytolytic.
    背景与目标: :检查了创伤弧菌溶血素(VVH)对大鼠腹膜腔肥大细胞的作用方式。 VVH以剂量依赖的方式诱导组胺释放和对肥大细胞的损害。当将1微克VVH添加到c中时。 10(5)肥大细胞在37摄氏度下,经过5-10 s的滞后时间后观察到组胺释放,并在5分钟内完成。该作用是温度依赖性的,并且在4℃下没有诱导。肥大细胞的膜稳定剂色甘酸二钠明显抑制组胺的释放,但作用不是剂量依赖性的。此外,观察到乳酸脱氢酶从VVH处理的肥大细胞中泄漏。这些结果表明,VVH作用于肥大细胞的细胞膜并具有溶细胞作用。
  • 【蛋白激酶D2通过NF-κB介导未转化的人结肠上皮细胞中溶血磷脂酸诱导的白介素8的产生。】 复制标题 收藏 收藏
    DOI:10.1152/ajpcell.00308.2006 复制DOI
    作者列表:Chiu TT,Leung WY,Moyer MP,Strieter RM,Rozengurt E
    BACKGROUND & AIMS: :The signaling pathways mediating lysophosphatidic acid (LPA)-stimulated PKD(2) activation and the potential contribution of PKD(2) in regulating LPA-induced interleukin 8 (IL-8) secretion in nontransformed, human colonic epithelial NCM460 cells were examined. Treatment of serum-deprived NCM460 cells with LPA led to a rapid and striking activation of PKD(2), as measured by in vitro kinase assay and phosphorylation at the activation loop (Ser706/710) and autophosphorylation site (Ser876). PKD(2) activation induced by LPA was abrogated by preincubation with selective PKC inhibitors GF-I and Ro-31-8220 in a dose-dependent manner. These inhibitors did not have any direct inhibitory effect on PKD(2) activity. LPA induced a striking increase in IL-8 production and stimulated NF-kappaB activation, as measured by NF-kappaB-DNA binding, NF-kappaB-driven luciferase reporter activity, and IkappaBalpha phosphorylation. PKD(2) gene silencing utilizing small interfering RNAs targeting distinct PKD(2) sequences dramatically reduced LPA-stimulated NF-kappaB promoter activity and IL-8 production. PKD(2) activation is a novel early event in the biological action of LPA and mediates LPA-stimulated IL-8 secretion in NCM460 cells through a NF-kappaB-dependent pathway. Our results demonstrate, for the first time, the involvement of a member of the PKD family in the production of IL-8, a potent proinflammatory chemokine, by epithelial cells.
    背景与目标: :审查了介导溶血磷脂酸(LPA)刺激的PKD(2)激活和PKD(2)在调节LPA诱导的非转化型人结肠上皮NCM460细胞中LPA诱导的白介素8(IL-8)分泌中的潜在作用。用体外LPA处理血清缺乏的NCM460细胞会导致PKD(2)迅速而惊人的活化,这是通过体外激酶测定和活化环(Ser706 / 710)和自磷酸化位点(Ser876)的磷酸化来测量的。通过与选择性PKC抑制剂GF-1和Ro-31-8220呈剂量依赖性方式进行预孵育,可以消除LPA诱导的PKD(2)激活。这些抑制剂对PKD(2)活性没有任何直接的抑制作用。如通过NF-κB-DNA结合,NF-κB驱动的萤光素酶报道分子活性和IkappaBalpha磷酸化所测量,LPA诱导IL-8产量显着增加并刺激NF-κB活化。 PKD(2)基因沉默利用针对不同的PKD(2)序列的小干扰RNA,大大降低了LPA刺激的NF-κB启动子活性和IL-8的产生。 PKD(2)激活是LPA的生物学作用中的一个新的早期事件,并通过NF-κB依赖性途径介导LCM刺激NCM460细胞中IL-8的分泌。我们的结果首次证明,上皮细胞参与了PKD家族成员参与IL-8(一种有效的促炎趋化因子)的生产。
  • 【缺氧条件下的肿瘤基质细胞相互作用通过肝细胞生长因子/ c-Met途径增加了胰腺癌细胞的侵袭性。】 复制标题 收藏 收藏
    DOI:10.1002/ijc.22178 复制DOI
    作者列表:Ide T,Kitajima Y,Miyoshi A,Ohtsuka T,Mitsuno M,Ohtaka K,Koga Y,Miyazaki K
    BACKGROUND & AIMS: :The hypoxic environment in tumor is reported to play an important role in pancreatic cancer progression. The interaction between stromal and cancer cells also contributes to the malignant behavior of pancreatic cancer. In the present study, we investigated whether hypoxic stimulation affects stromal as well as pancreatic cancer cells. Our findings demonstrated that hypoxia remarkably elevated the HIF-1alpha expression in both pancreatic cancer (PK8) and fibroblast cells (MRC5). Hypoxic stimulation accelerated the invasive activity of PK8 cells, and invasiveness was thus further accelerated when the hypoxic PK8 cells were cultured with conditioned medium prepared from hypoxic MRC5 cells (hypoxic conditioned medium). MMP-2, MMP-7, MT1-MMP and c-Met expressions were increased in PK8 cells under hypoxia. Hypoxic stimulation also increased the hepatocyte growth factor (HGF) secretion from MRC5 cells, which led to an elevation of c-Met phosphorylation in PK8 cells. Conversely, the elevated cancer invasion, MMP activity and c-Met phosphorylation of PK8 cells were reduced by the removal of HGF from hypoxic conditioned medium. In immunohistochemical study, the HIF-1alpha expression was observed in surrounding stromal as well as pancreatic cancer cells, thus indicating hypoxia exists in both of cancer and stromal cells. Moreover, the stromal HGF expression was found to significantly correlate with not only the stromal HIF-1alpha expression but also the c-Met expression in cancer cells. These results indicate that the hypoxic environment within stromal as well as cancer cells activates the HGF/c-Met system, thereby contributing to the aggressive invasive features of pancreatic cancer.
    背景与目标: :据报道肿瘤中的低氧环境在胰腺癌的进展中起重要作用。基质细胞与癌细胞之间的相互作用也有助于胰腺癌的恶性行为。在本研究中,我们调查了低氧刺激是否影响基质以及胰腺癌细胞。我们的发现表明,低氧显着提高了胰腺癌(PK8)和成纤维细胞(MRC5)中HIF-1alpha的表达。低氧刺激加速了PK8细胞的侵袭活性,因此,当用由低氧MRC5细胞制备的条件培养基(低氧条件培养基)培养低氧PK8细胞时,侵袭性进一步加快。在缺氧条件下,PK8细胞中的MMP-2,MMP-7,MT1-MMP和c-Met表达增加。缺氧刺激还增加了MRC5细胞的肝细胞生长因子(HGF)分泌,从而导致PK8细胞中c-Met磷酸化的升高。相反,通过从低氧条件培养基中去除HGF,可以降低PK8细胞的癌浸润,MMP活性和c-Met磷酸化水平的升高。在免疫组织化学研究中,在周围的基质细胞和胰腺癌细胞中均观察到了HIF-1alpha的表达,因此表明在癌细胞和基质细胞中均存在缺氧。此外,发现基质HGF表达不仅与癌细胞中的基质HIF-1α表达而且与c-Met表达显着相关。这些结果表明基质以及癌细胞内的低氧环境激活了HGF / c-Met系统,从而促进了胰腺癌的侵袭性侵袭性。

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