• 【通过微孔过滤测量的外周血中性粒细胞流变学很好地反映了白塞氏病的活动。】 复制标题 收藏 收藏
    DOI:10.1016/s0923-1811(97)00599-9 复制DOI
    作者列表:Iijima S,Otsuka F
    BACKGROUND & AIMS: Activated neutrophils take a long time to pass through a narrow lumen like a micropore, and are supposed to play a deteriorating effect on microcirculation. Although the activation of neutrophils has been demonstrated in Behçet's disease, nobody analyzes the clinical activity of the disease by means of the rheological measure of neutrophils activity. Using a micropore (pore diameter 5 microns) filtration technique, we measured the filtration time of peripheral blood neutrophils, as a rheological measure of their activity, in order to determine the clinical activity of Behçet's disease. Twenty-one patients with Behçet's disease and 14 healthy control individuals were enrolled in the study. Symptoms and signs exhibited in the patients led us to distinguish the Behçet's disease into inactive and active cases. The latter were further differentiated into cases with absent symptoms and with present symptoms. Neutrophil filtration times were 11.5 +/- 4.8 s in the active cases with present symptoms, which were significantly (P < 0.05) larger than those (7.4 +/- 1.9 s) in the active cases with absent symptoms. The latter filtration times were further significantly (P < 0.001) larger than values (3.7 +/- 1.3 s) in the inactive cases and also those (4.8 +/- 1.2 s) in control subjects. Furthermore, increases in the filtration time obtained immediately after the exposure of cells to the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (FMLP10 nM) were significantly (P < 0.01) larger in the active cases with present symptoms than those in the active cases with absent symptoms. The latter were also larger, but not significantly, than those in the inactive cases, and were significantly (P < 0.01) larger than those in control subjects. The present results demonstrate that the micropore filtration method reflects well the rheological activity of neutrophils as well as the clinical status of Behçet's disease. This method is much better than the measurement of O2 production to differentiate between active cases with absent symptoms and inactive patients or even control individuals. Furthermore, it is more sensitive and useful than laboratory data like the CRP value or the number of peripheral blood neutrophils.

    背景与目标: 活化的中性粒细胞需要很长时间才能通过像微孔一样的狭窄管腔,并且应该对微循环起到恶化的作用。尽管在beh ç et病中已经证明了中性粒细胞的激活,但没有人通过中性粒细胞活性的流变学测量来分析该疾病的临床活性。使用微孔 (孔径5微米) 过滤技术,我们测量了外周血中性粒细胞的过滤时间,作为其活性的流变学指标,以确定白塞氏病的临床活性。21名beh ç et病患者和14名健康对照者参加了这项研究。患者表现出的症状和体征使我们将白塞氏病区分为不活跃和活跃的病例。后者进一步分为无症状和现有症状的病例。有症状的活动病例的中性粒细胞过滤时间为11.5 +/- 4.8 s,显著 (P < 0.05) 大于无症状的活动病例的中性粒细胞过滤时间 (7.4 +/- 1.9 s)。后者的过滤时间进一步显著 (P < 0.001) 大于非活性情况下的值 (3.7 +/- 1.3 s),也大于对照受试者中的值 (4.8 +/- 1.2 s)。此外,在细胞暴露于趋化肽甲酰基-甲硫酰基-亮氨酸-苯丙氨酸 (fmlp10nm) 后立即获得的过滤时间的增加在存在症状的活动病例中比在不存在症状的活动病例中显着 (P < 0.01) 大。后者也比不活跃的情况更大,但不显著,并且显著 (P < 0.01) 大于对照组。目前的结果表明,微孔过滤方法很好地反映了嗜中性粒细胞的流变活性以及白塞病的临床状况。此方法比O2产生的测量要好得多,可以区分无症状的活跃病例和不活跃的患者甚至对照组。此外,它比CRP值或外周血中性粒细胞数量等实验室数据更敏感和有用。
  • 【体外药物活性和药代动力学在预测抗分枝杆菌治疗有效性中的价值: 一项重要综述。】 复制标题 收藏 收藏
    DOI:10.1097/00000441-199706000-00008 复制DOI
    作者列表:Burman WJ
    BACKGROUND & AIMS: Marked increases in case rates of drug-resistant tuberculosis and nontuberculous mycobacterial infections have brought renewed urgency to the development of new treatment regimens for mycobacterial infections. Preclinical data, such as in vitro measures of drug activity and pharmacokinetics, are used in the design of new treatment regimens. This review surveys the extensive published clinical experience concerning the treatment of drug-susceptible tuberculosis to evaluate the use of these preclinical measures in predicting clinical outcomes of antimycobacterial therapy. In vitro measures of drug activity predict the potency of a drug to prevent the emergence of resistance to other antimycobacterial drugs but do not predict the sterilizing activity of a drug or the activity of drug combinations. In vitro measures of drug activity do not allow reliable predictions of the level at which an organism should be considered resistant. Assays of drug penetration in tissues and activity against intracellular bacilli add modestly to the predictive value of in vitro measures of drug activity but still do not predict sterilizing activity. In contrast, animal models of tuberculosis have predicted relative drug potency (including sterilizing activity), the efficacy of multidrug regimens, and the duration of therapy needed. Despite pharmacokinetic parameters that would suggest the need for multiple doses per day, all of the first-line antituberculous drugs are active when given as infrequently as twice weekly. It is difficult to predict the efficacy of therapy for an intracellular pathogen that has the capacity for dormancy. Better in vitro models are needed, particularly ones that predict sterilizing activity.

    背景与目标: 耐药结核病和非结核分枝杆菌感染的病例率显着增加,为开发新的分枝杆菌感染治疗方案带来了新的紧迫性。临床前数据,例如药物活性和药代动力学的体外测量,用于设计新的治疗方案。这篇综述调查了有关药物敏感结核病治疗的广泛已发表的临床经验,以评估这些临床前措施在预测抗细菌治疗临床结果中的应用。药物活性的体外测量可以预测药物的效力,以防止对其他抗细菌药物的耐药性出现,但不能预测药物的灭菌活性或药物组合的活性。药物活性的体外测量无法可靠地预测生物体应被认为具有抗性的水平。药物在组织中的渗透和对细胞内杆菌的活性的测定适度增加了药物活性的体外测量的预测值,但仍不能预测灭菌活性。相反,结核病的动物模型已经预测了相对的药物效力 (包括灭菌活性),多药疗法的功效以及所需的治疗持续时间。尽管药代动力学参数表明每天需要多次剂量,但所有一线抗结核药物在每周两次的情况下均具有活性。很难预测具有休眠能力的细胞内病原体的治疗效果。需要更好的体外模型,尤其是可以预测灭菌活性的模型。
  • 【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: 与大鼠腺癌反应的CD4 + 抗肿瘤T细胞13762在体外杀伤肿瘤并在体内引起肿瘤的消退。通过将抗肿瘤T细胞克隆过继转移到选择性耗尽个体免疫细胞类型的受体,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。通过这些方法,发现巨噬细胞和NK细胞是杀死肿瘤所必需的。宿主CD4 T细胞,CD8 T细胞或中性粒细胞的耗竭对抗肿瘤T细胞消除肿瘤没有影响。抗原受体阴性NK细胞的重要作用可能取决于NK细胞中IFN-γ 的分泌,因为在过继转移和肿瘤挑战之前用抗IFN-γ 抗体治疗肿瘤接受者消除了T细胞杀伤,导致进行性肿瘤生长。腺癌13762或抗肿瘤T细胞的活力在体外不受IFN-γ 或抗IFN-γ 抗体治疗的影响,但细胞表面mhcii类表达通过暴露于IFN-γ 在肿瘤细胞中诱导。此外,通过使用抗MHC II类抗体吸收从荷瘤动物中分离肿瘤细胞,证明13762肿瘤原位表达细胞表面MHC II类抗原。但是,如果宿主在肿瘤激发之前耗尽了NK细胞,则MHC II类肿瘤将无法恢复。这些结果共同表明,通过直接杀伤肿瘤,MHC II类限制性CD4 T细胞消除了腺癌13762。
  • 【神经元活动的同步促进单个大鼠新皮层神经元在早期发育中的存活。】 复制标题 收藏 收藏
    DOI:10.1111/j.1460-9568.1997.tb01449.x 复制DOI
    作者列表:Voigt T,Baier H,Dolabela de Lima A
    BACKGROUND & AIMS: Neural activity is thought to play a significant role during the development of the cerebral cortex. In this study, we examined the effects of global activity block or enhancement and the effects of patterned firing on the ability of cultured rat neocortical neurons to survive during the second week in vitro, beyond the beginning of synaptogenesis. Blockade of neuronal activity by adding tetrodotoxin (TTX) and increasing magnesium concentration in the medium strongly reduced the survival of cortical cells. Increasing neuronal activity by raising the external potassium concentration significantly improved the survival of cortical neurons. We postulated that in a developing neuronal network the survival of nerve cells is regulated by synaptically mediated events that involve changes in the intracellular calcium concentration. To examine this question further, we monitored the activity of the developing network by optically recording the intracellular calcium signals of many neurons simultaneously. These recordings show that in low magnesium neocortical neurons express synchronized oscillation of their intracellular calcium concentration. The ability of a network to synchronize the changes in intracellular calcium of multiple cells appeared gradually during the second week in culture, paralleled by both an increase in the synaptic density and a decline in the number of surviving neurons. By examining the fate of identified cells several days after a recording session, we found that those nerve cells that were co-activated with other neurons had a significantly higher chance to survive than cells that did not participate in synchronized events. These experiments demonstrate that during early cortical network development cortical neurons show synchronized firing activity and that the survival of neurons is at least partially dependent on this pattern of neuronal activity.

    背景与目标: 神经活动被认为在大脑皮层发育过程中起着重要作用。在这项研究中,我们研究了整体活动阻滞或增强的影响以及图案化放电对培养的大鼠新皮层神经元在体外第二周 (突触开始后) 存活的能力的影响。通过添加河豚毒素 (TTX) 和增加培养基中的镁浓度来阻断神经元活性,从而大大降低了皮质细胞的存活。通过提高外部钾浓度来增加神经元活性,显着改善了皮质神经元的存活。我们推测,在发育中的神经元网络中,神经细胞的存活受到突触介导的事件的调节,这些事件涉及细胞内钙浓度的变化。为了进一步研究这个问题,我们通过同时光学记录许多神经元的细胞内钙信号来监测发育网络的活动。这些记录表明,在低镁的新皮层神经元中,其细胞内钙浓度表达同步振荡。在培养的第二周,网络使多个细胞的细胞内钙的变化同步的能力逐渐出现,同时突触密度增加和存活神经元数量减少。通过在记录过程几天后检查已识别细胞的命运,我们发现与其他神经元共同激活的神经细胞比不参与同步事件的细胞存活的机会要高得多。这些实验表明,在早期皮质网络发育过程中,皮质神经元显示出同步的放电活动,并且神经元的存活至少部分取决于这种神经元活动模式。
  • 【靶向抗龋DNA疫苗的免疫原性和持久性。】 复制标题 收藏 收藏
    DOI:10.1177/154405910608501008 复制DOI
    作者列表:Xu QA,Yu F,Fan MW,Bian Z,Chen Z,Fan B,Jia R,Guo JH
    BACKGROUND & AIMS: :We have previously reported that a targeted anti-caries DNA vaccine, pGJA-P, induced accelerated and increased antibody responses compared with a non-targeted anti-caries DNA vaccine. Recently, pGJA-P/VAX, a new targeted anti-caries DNA vaccine for human trials, was constructed by replacing the pCI vector used in the construction of pGJA-P with pVAX1, the only vector authorized by the US Food and Drug Administration in clinical trials. Here, we report on our exploration of the kinetics of the antibody responses generated following pGJA-P/VAX immunization and the persistence of pGJA-P/VAX at both the inoculation site and the draining lymph nodes. Intranasal vaccination of mice with pGJA-P/VAX induced strong antibody responses that lasted for more than 6 months. Furthermore, pGJA-P/VAX could still be detected at both the inoculation site and the draining cervical lymph nodes 6 months after immunization. Thus, the persistent immune responses are likely due to the DNA depot in the host, which acts as a booster immunization.
    背景与目标: : 我们以前曾报道过,与非靶向抗龋DNA疫苗相比,靶向抗龋DNA疫苗pGJA-P诱导了加速和增加的抗体反应。最近,pGJA-P/VAX是一种用于人体试验的新型靶向抗龋齿DNA疫苗,通过用pVAX1代替用于构建pGJA-P的pCI载体,这是美国食品药品监督管理局在临床试验中唯一授权的载体。在这里,我们报告了我们对pGJA-P/VAX预防接种后产生的抗体反应的动力学以及pGJA-P/VAX在接种部位和引流淋巴结的持久性的探索。用pGJA-P/VAX对小鼠进行鼻内疫苗接种可诱导持续6个月以上的强烈抗体反应。此外预防接种后6个月,在接种部位和引流颈淋巴结中仍可检测到pGJA-P/VAX。因此,持续的免疫反应可能是由于宿主中的DNA储存库而起加强预防接种作用。
  • 【通过Farr和ELISA技术进行的抗dsDNA抗体测试是不等效的。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Neogi T,Gladman DD,Ibanez D,Urowitz M
    BACKGROUND & AIMS: OBJECTIVE:To determine the degree of correlation between Farr and ELISA methods of detecting anti-dsDNA antibodies in patients with systemic lupus erythematosus (SLE), and their association with measures of disease activity. METHODS:Anti-dsDNA antibodies were assayed using the Farr and ELISA methods in patients followed between January 1, 2000, and December 31, 2002. Statistical correlations between Farr and ELISA were determined. Relationships between the 2 assays and measures of disease activity [SLE Disease Activity Index 2000 (SLEDAI-2K-DNA), renal, central nervous system (CNS), and vasculitis] were determined for the same clinic visit. RESULTS:550 patients with 2940 clinic visits met the inclusion criteria. Correlation between Farr and ELISA levels was 0.46 using the first visit for each patient. When the Farr was abnormal, the ELISA was equally likely to be normal or abnormal. Abnormal Farr results were associated with higher SLEDAI-2K scores than normal Farr results (6.2 vs 4.3, respectively; p < 0.0001). There was less of a distinction with ELISA results (5.9 vs 4.8; p = 0.04). Farr levels were significantly associated with the presence of renal disease and vasculitis, while ELISA levels were not. Neither Farr nor ELISA results correlated with the presence of active CNS involvement. CONCLUSION:Farr and ELISA techniques for the detection of anti-dsDNA antibodies in patients with SLE are poorly correlated. The Farr is superior to the ELISA in correlating with measures of global disease activity, as well as renal and vasculitis involvement. The Farr technique should continue to be used in clinical practice. The ELISA adds no additional information.
    背景与目标:
  • 【一系列赛庚胺类似物的合成,对5-HT2A,5-HT2B和5-HT2C 5-羟色胺受体的亲和力和结构-活性关系。】 复制标题 收藏 收藏
    DOI:10.1248/cpb.45.842 复制DOI
    作者列表:Honrubia MA,Rodriguez J,Dominguez R,Lozoya E,Manaut F,Seijas JA,Villaverde MC,Calleja JM,Cadavid MI,Maayani S,Sanz F,Loza MI
    BACKGROUND & AIMS: :Cyproheptadine is a drug that shows high affinity for type 2 (5-HT2) receptors. We studied a series of compounds obtained by modification of the tricyclic system of Cyp (dibenzocycloheptadiene): 2f (thioxanthene), 2g (xanthene), 2h (dihydrodibenzocycloheptadiene), 2j (diphenyl), 2i (fluorene), and 3b (phenylmethyl). Their activities at the rat cerebral cortex 5-HT2A receptor were (pKi +/- S.E.M.): 8.80 +/- 0.11 (Cyp), 8.60 +/- 0.07 (2f), 8.40 +/- 0.02 (2g), 8.05 +/- 0.03 (2h), 7.87 +/- 0.12 (2j), 6.70 +/- 0.02 (2i) and 6.45 +/- 0.02 (3b); those at the rat stomach fundus 5-HT2B receptor (pA2 +/- S.E.M.) were: 9.14 +/- 0.25 (Cyp), 8.49 +/- 0.07 (2f), 7.58 +/- 0.58 (2g), 7.02 +/- 0.14 (2h), 6.07 +/- 0.20 (2j), and undetectable (2i, 3b): and those at the pig choroidal plexus 5-HT2C receptor (pKi +/- S.E.M.) were: 8.71 +/- 0.08 (Cyp), 8.68 +/- 0.01 (2f), 8.58 +/- 0.20 (2g), 7.95 +/- 0.05 (2h), 7.57 +/- 0.04 (2j), 6.98 +/- 0.04 (2i) and 6.63 +/- 0.20 (3b). The slopes did not differ significantly from unity. The compounds exhibited the same order of activities at every type of receptor, and the most active molecules presented certain steric (butterfly conformation of the tricyclic system) and electrostatic (proton affinity on the top of the central rings) patterns. It is concluded that the activity of cyproheptadine derivatives at 5-HT2 receptors is related to these molecular features, which make feasible a common disposition to interact with all three 5-HT2 subtypes.
    背景与目标: : 赛庚胺是一种对2型 (5-HT2) 受体显示高亲和力的药物。我们研究了通过修饰Cyp (二苯并环庚二烯) 的三环体系获得的一系列化合物: 2f (噻吩),2g (xanthene),2h (二氢二苯并环庚二烯),2j (二苯基),2i (芴) 和3b (苯基甲基)。它们在大鼠大脑皮层5-HT2A受体上的活性为 (pKi +/-s.e.M.): 8.80 +/- 0.11 (Cyp),8.60 +/- 0.07 (2f),8.40 +/- 0.02 (2g),8.05 +/- 0.03 (2h),7.87 +/- 0.12 (2j),6.70 +/- 0.02 (2i) 和6.45 +/- 0.02 (3b); 大鼠胃底5-HT2B受体 (pA2 +/-s.e.M.) 为: 9.14 +/- 0.25 (Cyp),8.49 +/- 0.07 (2f),7.58 +/- 0.58 (2g),7.02 +/- 0.14 (2h),6.07 +/- 0.20 (2j) 和不可检测 (2i,3b): 猪脉络丛5-HT2C受体 (pKi +/-s.e.M.) 为: 8.71 +/- 0.08 (Cyp),8.68 +/- 0.01 (2f),8.58 +/- 0.20 (2g),7.95 +/- 0.05 (2h) 、7.57 +/- 0.04 (2j) 、6.98 +/- 0.04 (2i) 和6.63 +/- 0.20 (3b)。坡度与统一没有显着差异。这些化合物在每种类型的受体上都表现出相同的活性顺序,并且最具活性的分子呈现某些空间 (三环系统的蝴蝶构象) 和静电 (中心环顶部的质子亲和力) 模式。结论是,赛庚胺衍生物在5-HT2受体上的活性与这些分子特征有关,这使得与所有三种5-HT2亚型相互作用的共同处置是可行的。
  • 【注意缺陷多动障碍可能与中枢脑源性神经营养因子活性降低有关: 临床和治疗意义。】 复制标题 收藏 收藏
    DOI:10.1016/j.mehy.2006.06.025 复制DOI
    作者列表:Tsai SJ
    BACKGROUND & AIMS: :Attention-deficit hyperactivity disorder (ADHD) is a common childhood psychiatric disorder. Despite intensive research efforts, the aetiology of ADHD remains unknown. Current evidence suggests that the aetiology of ADHD is heterogeneous, comprising of multiple factors. Recently, it has been proposed that brain-derived neurotrophic factor (BDNF), a member of the neurotrophic factor family, may be implicated in the pathogenesis of ADHD. This hypothesis is supported by recent genetic studies in ADHD. Drawing on findings from studies into the drugs for ADHD relating to central BDNF expression, hyperactivity in BDNF knockout mice, BDNF effects in midbrain dopaminergic function and the close association between BDNF and the dopamine transporter (an important molecule for ADHD pathogenesis), it is proposed here that decreased central BDNF, particularly in the midbrain region, may play an important role in the pathogenesis ADHD. This hypothesis may have some implications for clinical findings in ADHD (for example, the co-morbidity between ADHD and major depression), and provide a new direction for the development of medication for ADHD treatment.
    背景与目标: : 注意力缺陷多动障碍 (ADHD) 是一种常见的儿童精神疾病。尽管进行了大量研究,但ADHD的病因仍然未知。目前的证据表明,ADHD的病因是异质的,由多种因素组成。最近,有人提出,神经营养因子家族的成员脑源性神经营养因子 (BDNF) 可能与ADHD的发病机理有关。该假设得到了ADHD最近的遗传研究的支持。根据对ADHD药物的研究结果,该药物与中枢BDNF表达,BDNF基因敲除小鼠的活动过度,BDNF在中脑多巴胺能功能中的作用以及BDNF与多巴胺转运蛋白 (ADHD发病机理的重要分子) 之间的密切联系有关,在这里提出降低中枢BDNF,特别是在中脑区域,可能在ADHD的发病机理中起重要作用。该假设可能对ADHD的临床发现 (例如,ADHD与重度抑郁症之间的合并症) 具有一定的意义,并为ADHD治疗药物的发展提供了新的方向。
  • 【新型anti-CD4单克隆抗体可分离人类免疫缺陷病毒感染和CD4细胞融合与病毒结合。】 复制标题 收藏 收藏
    DOI:10.1084/jem.172.4.1233 复制DOI
    作者列表:Healey D,Dianda L,Moore JP,McDougal JS,Moore MJ,Estess P,Buck D,Kwong PD,Beverley PC,Sattentau QJ
    BACKGROUND & AIMS: :Human immunodeficiency virus (HIV) binds to cells via an interaction between CD4 and the virus envelope glycoprotein, gp120. Previous studies have localized the high affinity binding site for gp120 to the first domain of CD4, and monoclonal antibodies (mAbs) reactive with this region compete with gp120 binding and thereby block virus infectivity and syncytium formation. Despite a detailed understanding of the binding of gp120 to CD4, little is known of subsequent events leading to membrane fusion and virus entry. We describe two new mAbs reactive with the third domain of CD4 that inhibit steps subsequent to virus binding critical for HIV infectivity and cell fusion. Binding of recombinant gp120 or virus to CD4 is not inhibited by these antibodies, whereas infection and syncytium formation by a number of HIV isolates are blocked. These findings demonstrate that in addition to virus binding, CD4 may have an active role in membrane fusion.
    背景与目标: : 人类免疫缺陷病毒 (HIV) 通过CD4与病毒包膜糖蛋白gp120之间的相互作用与细胞结合。先前的研究已将gp120的高亲和力结合位点定位于CD4的第一个结构域,与该区域反应性的单克隆抗体 (mab) 与gp120的结合竞争,从而阻止病毒的感染性和合胞体的形成。尽管对gp120与CD4的结合有详细的了解,但对导致膜融合和病毒进入的后续事件知之甚少。我们描述了两种与CD4的第三结构域反应的新mab,它们抑制了对HIV感染性和细胞融合至关重要的病毒结合之后的步骤。重组gp120或病毒与CD4的结合不受这些抗体的抑制,而许多HIV分离株的感染和合胞体形成被阻断。这些发现表明,除了病毒结合外,CD4可能在膜融合中起积极作用。
  • 【具有NMDA拮抗剂活性的天然衍生肽抑制神经病理性疼痛。】 复制标题 收藏 收藏
    DOI:10.1016/s0006-8993(97)00183-2 复制DOI
    作者列表:Siegan JB,Hama AT,Sagen J
    BACKGROUND & AIMS: :Chronic pain may result from hyperexcitability following activation of spinal NMDA receptors. A naturally-derived mammalian peptide, histogranin, may possess NMDA antagonist activity. This study explored the possibility that stable analog [Ser1]Histogranin (SHG) could reduce chronic pain. Neuropathic pain was induced using the chronic constriction injury model (CCI). Intrathecal injection of SHG markedly attenuated the hyperalgesia and allodynia resulting from CCI, nearly normalizing responses. These results suggest that the natural peptide histogranin may be a novel adjunct in neuropathic pain management.
    背景与目标: : 脊髓NMDA受体激活后过度兴奋可能导致慢性疼痛。天然衍生的哺乳动物肽组织蛋白可能具有NMDA拮抗剂活性。这项研究探讨了稳定的类似物 [Ser1] 组织蛋白 (SHG) 可以减轻慢性疼痛的可能性。使用慢性收缩损伤模型 (CCI) 诱发神经病理性疼痛。鞘内注射SHG可显着减轻由CCI引起的痛觉过敏和异常性疼痛,几乎使反应正常化。这些结果表明,天然肽组织粒蛋白可能是神经性疼痛管理的新型辅助手段。
  • 【牙龈卟啉单胞菌主动调节 β2整合素粘附活性并促进与巨噬细胞的结合和内化。】 复制标题 收藏 收藏
    DOI:10.1128/IAI.00784-06 复制DOI
    作者列表:Hajishengallis G,Wang M,Harokopakis E,Triantafilou M,Triantafilou K
    BACKGROUND & AIMS: :In monocytes, the fimbriae of the oral pathogen Porphyromonas gingivalis activate cross talk signaling from Toll-like receptor 2 (TLR2) to the beta2 integrin CD11b/CD18, leading to the induction of the high-affinity state of the latter receptor. CD14 plays an important role in this "inside-out" proadhesive pathway by binding fimbriae and facilitating the activation of TLR2 and phosphatidylinositol 3-kinase signaling. In its high-affinity state, CD11b/CD18 mediates monocyte adhesion to endothelial cells and transmigration to sites of infection. We have now shown that P. gingivalis fimbriae function as both an activator and a ligand of CD11b/CD18; thus, fimbriae proactively promote their own binding to monocytes. Indeed, treatments that interfered with fimbria-induced activation of CD11b/CD18 (i.e., blockade of CD14, TLR2, or phosphatidylinositol 3-kinase signaling) also suppressed the cell binding activity of fimbriae, which was largely inducible and CD11b/CD18 dependent. Development of a recombinant inside-out signaling system in Chinese hamster ovary cells confirmed the ability of fimbriae to activate CD14/TLR2 signaling and induce their own CD11b/CD18-dependent binding. Induction of this proadhesive pathway by P. gingivalis fimbriae appeared to take place in lipid rafts. Indeed, methyl-beta-cyclodextrin, a cholesterol-sequestering agent that disrupts lipid raft organization, was found to inhibit the fimbria-induced assembly of CD14/TLR2 signaling complexes and the activation of the high-affinity state of CD11b/CD18. Experiments using macrophages from mice deficient in various pattern recognition receptors indicated that the receptors involved in the inside-out proadhesive pathway (CD14, TLR2, and CD11b/CD18) are important for mediating P. gingivalis internalization within macrophages. It therefore appears that P. gingivalis proactively modulates beta2 integrin adhesive activity for intracellular uptake.
    背景与目标: : 在单核细胞中,口腔病原体牙龈卟啉单胞菌的菌毛激活从Toll样受体2 (TLR2) 到 β2整合素CD11b/CD18的串扰信号,导致诱导后者受体的高亲和力状态。CD14通过结合菌毛并促进TLR2和磷脂酰肌醇3-激酶信号的激活,在这种 “由内而外” 的前粘附途径中起重要作用。在其高亲和力状态下,CD11b/CD18介导单核细胞与内皮细胞的粘附并转移到感染部位。我们现在已经证明,牙龈卟啉单胞菌菌毛既是CD11b/CD18的激活剂又是配体。因此,菌毛会主动促进其自身与单核细胞的结合。实际上,干扰菌毛诱导的CD11b/CD18激活 (即CD14,TLR2或磷脂酰肌醇3-激酶信号传导的阻断) 的治疗也抑制了菌毛的细胞结合活性,这在很大程度上是可诱导的并且CD11b/CD18依赖性。在中国仓鼠卵巢细胞中开发了重组的由内而外信号系统,证实了菌毛激活CD14/TLR2信号并诱导其自身CD11b/CD18-dependent结合的能力。牙龈卟啉单胞菌诱导这种前粘附途径似乎发生在脂质筏中。实际上,发现甲基-β-环糊精是一种破坏脂质筏组织的胆固醇螯合剂,可抑制菌毛诱导的CD14/TLR2信号复合物的组装以及CD11b/cd18高亲和力状态的激活。使用缺乏各种模式识别受体的小鼠的巨噬细胞进行的实验表明,参与由内而外的前粘附途径 (CD14,TLR2和CD11b/CD18) 的受体对于介导巨噬细胞内牙龈卟啉单胞菌内化很重要。因此,似乎牙龈卟啉单胞菌主动调节 β2整合素粘附活性以促进细胞内摄取。
  • 【用黄色荧光蛋白变体YFP-H148Q/I152L对碘化钠同向转运体活性的细胞成像。】 复制标题 收藏 收藏
    DOI:10.1152/ajpcell.00291.2006 复制DOI
    作者列表:Rhoden KJ,Cianchetta S,Stivani V,Portulano C,Galietta LJ,Romeo G
    BACKGROUND & AIMS: :The sodium iodide symporter (NIS) mediates iodide (I(-)) transport in the thyroid gland and other tissues and is of increasing importance as a therapeutic target and nuclear imaging reporter. NIS activity in vitro is currently measured with radiotracers and electrophysiological techniques. We report on the development of a novel live cell imaging assay of NIS activity using the I(-)-sensitive and genetically encodable yellow fluorescent protein (YFP) variant YFP-H148Q/I152L. In FRTL-5 thyrocytes stably expressing YFP-H148Q/I152L, I(-) induced a rapid and reversible decrease in cellular fluorescence characterized by 1) high affinity for extracellular I(-) (35 muM), 2) inhibition by the NIS inhibitor perchlorate, 3) extracellular Na(+) dependence, and 4) TSH dependence, suggesting that fluorescence changes are due to I(-) influx via NIS. Individual cells within a population of FRTL-5 cells exhibited a 3.5-fold variation in the rate of NIS-mediated I(-) influx, illustrating the utility of YFP-H148Q/I152L to detect cell-to-cell difference in NIS activity. I(-) also caused a perchlorate-sensitive decrease in YFP-H148Q/I152L fluorescence in COS-7 cells expressing NIS but not in cells lacking NIS. These results demonstrate that YFP-H148Q/I152L is a sensitive biosensor of NIS-mediated I(-) uptake in thyroid cells and in nonthyroidal cells following gene transfer and suggest that fluorescence detection of cellular I(-) may be a useful tool by which to study the pathophysiology and pharmacology of NIS.
    背景与目标: : 碘化钠同向转运体 (NIS) 介导碘 (I(-)) 在甲状腺和其他组织中的转运,作为治疗靶标和核成像报告基因的重要性日益提高。目前使用放射性示踪剂和电生理技术测量体外的NIS活性。我们报告了使用I(-) 敏感且可遗传编码的黄色荧光蛋白 (YFP) 变体YFP-H148Q/I152L对NIS活性进行新型活细胞成像测定的开发。在稳定表达YFP-H148Q/I152L的FRTL-5甲状腺细胞中,I(-) 诱导细胞荧光的快速和可逆降低,其特征是1) 对细胞外I(-) (35 muM) 的高亲和力,2) NIS抑制剂高氯酸盐的抑制,3) 细胞外Na(+) 依赖性,和4) TSH依赖性,表明荧光变化是由于I(-) 通过NIS流入所致。FRTL-5细胞群内的单个细胞表现出NIS介导的I(-) 流入速率的3.5倍变化,说明YFP-H148Q/I152L用于检测NIS活性的细胞间差异。I(-) 还导致表达NIS的COS-7细胞中YFP-H148Q/I152L荧光的高氯酸盐敏感降低,但在缺乏NIS的细胞中不引起。这些结果表明,YFP-H148Q/I152L是基因转移后甲状腺细胞和非甲状腺细胞中NIS介导的I(-) 摄取的敏感生物传感器,并表明细胞I(-) 的荧光检测可能是研究的有用工具。NIS的病理生理学和药理学。
  • 【尿激酶型纤溶酶原激活剂和基质金属蛋白酶在大肠癌中的活性和表达。】 复制标题 收藏 收藏
    DOI:10.1186/1471-2407-6-211 复制DOI
    作者列表:Kim TD,Song KS,Li G,Choi H,Park HD,Lim K,Hwang BD,Yoon WH
    BACKGROUND & AIMS: BACKGROUND:Matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), and urokinase-type plasminogen activator (uPA) are involved in colorectal cancer invasion and metastasis. There is still debate whether the activity of MMP-2 and MMP-9 differs between tumors located in the colon and rectum. We designed this study to determine any differences in the expression of MMP-2, MMP-9 and uPA system between colon and rectal cancer tissues. METHODS:Cancer tissue samples were obtained from colon carcinoma (n = 12) and rectal carcinomas (n = 10). MMP-2 and MMP-9 levels were examined using gelatin zymography and Western blotting; their endogenous inhibitors, tissue inhibitor of metalloproteinase-2 (TIMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1), were assessed by Western blotting. uPA, uPAR and PAI-1 were examined using enzyme-linked immunosorbent assay (ELISA). The activity of uPA was assessed by casein-plasminogen zymography. RESULTS:In both colon and rectal tumors, MMP-2, MMP-9 and TIMP-1 protein levels were higher than in corresponding paired normal mucosa, while TIMP-2 level in tumors was significantly lower than in normal mucosa. The enzyme activities or protein levels of MMP-2, MMP-9 and their endogenous inhibitors did not reach a statistically significant difference between colon and rectal cancer compared with their normal mucosa. In rectal tumors, there was an increased activity of uPA compared with the activity in colon tumors (P = 0.0266), however urokinase-type plasminogen activator receptor (uPAR) and plasminogen activator inhibitor-1 (PAI-1) showed no significant difference between colon and rectal cancer tissues. CONCLUSION:These findings suggest that uPA may be expressed differentially in colon and rectal cancers, however, the activities or protein levels of MMP-2, MMP-9, TIMP-1, TIMP-2, PAI-1 and uPAR are not affected by tumor location in the colon or the rectum.
    背景与目标:
  • 【快速荧光法测量pendrin (SLC26A4) Cl-/I-转运活性。】 复制标题 收藏 收藏
    DOI:10.1159/000095164 复制DOI
    作者列表:Dossena S,Rodighiero S,Vezzoli V,Bazzini C,Sironi C,Meyer G,Fürst J,Ritter M,Garavaglia ML,Fugazzola L,Persani L,Zorowka P,Storelli C,Beck-Peccoz P,Bottá G,Paulmichl M
    BACKGROUND & AIMS: :Malfunction of the SLC26A4 protein leads to Pendred syndrome, characterized by sensorineural hearing loss, often associated with mild thyroid dysfunction and goiter. It is generally assumed that SLC26A4 acts as a chloride/anion exchanger, which in the thyroid gland transports iodide, and in the inner ear contributes to the conditioning of the endolymphatic fluid. Here we describe a fast fluorometric method able to be used to functionally scrutinize SLC26A4 and its mutants described in Pendred syndrome. The validation of the method was done by functionally characterizing the chloride/iodide transport of SLC26A4, and a mutant, i.e. SLC26A4(S28R), which we previously described in a patient with sensorineural hearing loss, hypothyroidism and goiter. Using the fluorometric method we describe here we can continuously monitor and quantify the iodide or chloride amounts transported by the cells, and we found that the transport capability of the SLC26A4(S28R) mutant protein is markedly reduced if compared to wild-type SLC26A4.
    背景与目标: : SLC26A4蛋白的故障导致Pendred综合征,其特征是感音神经性听力损失,通常与轻度甲状腺功能障碍和甲状腺肿有关。通常认为SLC26A4充当氯化物/阴离子交换剂,在甲状腺中转运碘化物,在内耳中有助于调节内淋巴液。在这里,我们描述了一种快速荧光测量方法,该方法能够用于功能检查SLC26A4及其在Pendred综合征中描述的突变体。该方法的验证是通过功能表征SLC26A4的氯化物/碘化物转运和突变体即SLC26A4(S28R) 来完成的,我们先前在患有感音神经性听力损失,甲状腺功能减退和甲状腺肿的患者中进行了描述。使用我们在这里描述的荧光法,我们可以连续监测和定量细胞转运的碘化物或氯化物量,并且我们发现与野生型SLC26A4相比,SLC26A4(S28R) 突变蛋白的转运能力显着降低。
  • 【修饰的酶原作为蛋白水解酶的人工底物: 使用修饰的尿激酶原比色测定细菌胶原酶和基质金属蛋白酶的活性。】 复制标题 收藏 收藏
    DOI:10.1042/bj3230603 复制DOI
    作者列表:Verheijen JH,Nieuwenbroek NM,Beekman B,Hanemaaijer R,Verspaget HW,Ronday HK,Bakker AH
    BACKGROUND & AIMS: We describe a new principle for assessment of the activity of proteolytic enzymes of all classes and show the application of this principle for the quantitative assay of bacterial collagenase and human matrix metalloproteinases (MMPs). Central to this new principle is the presence of a proenzyme that can be activated into an active enzyme by a single proteolytic event. The regular activation sequence in the proenzyme is replaced using protein engineering by an artificial sequence recognized by the proteinase to be determined. The latter can act as an activator for the newly engineered proenzyme. In the present paper a simple colorimetric assay for the determination for MMPs is described based on this principle. With the aid of protein engineering, a modified pro-urokinase has been prepared in which the activation sequence normally recognized by plasmin (Pro-Arg-Phe-Lys upward arrowIle-Ile-Gly-Gly) has been replaced by a sequence expected to be recognized and hydrolysed by many MMPs (Arg-Pro-Leu-Gly upward arrowIle-Ile-Gly-Gly). The active urokinase resulting from activation of the modified pro-urokinase by a MMP could be measured either directly, using a specific chromogenic peptide substrate for urokinase, or indirectly via urokinase-catalysed plasminogen activation. The response of the assay to equal molar quantities of active MMPs decreases in the order MMP-2>MMP-9>MMP-1>MMP-3>MMP-7. The detection limit for MMP-9 was below 15 pM, corresponding to 3. 75x10(-15) mol per assay. Using the assay, increased MMP activity was detected in synovial tissue extracts from rheumatoid arthritis patients compared with those from osteoarthritis patients, and in stomach tumour extracts as compared with normal stomach tissue extracts.

    背景与目标: 我们描述了一种评估所有类别蛋白水解酶活性的新原理,并展示了该原理在细菌胶原酶和人类基质金属蛋白酶 (MMPs) 定量测定中的应用。这一新原理的核心是存在一种原酶,该原酶可以通过一次蛋白水解事件被激活为活性酶。使用蛋白质工程技术将原酶中的常规激活序列替换为待确定的蛋白酶识别的人工序列。后者可以作为新改造的原酶的激活剂。在本文中,基于此原理描述了一种用于确定MMPs的简单比色测定法。借助蛋白质工程,已经制备了一种改良的尿激酶原,其中通常由纤溶酶识别的激活序列 (pro-Arg-Phe-Lys向上arrowIle-Ile-Gly) 已被预期被许多MMPs识别和水解的序列所取代 (Arg-Pro-Leu-Gly向上arrowIle-ile-Gly)。通过MMP激活修饰的尿激酶原而产生的活性尿激酶可以直接,使用尿激酶的特定显色肽底物进行测量,也可以通过尿激酶催化的纤溶酶原活化间接测量。测定对相等摩尔量的活性mmp的响应以MMP-2>MMP-9>MMP-1>MMP-3>MMP-7的顺序降低。MMP-9的检测限低于15μm,对应于3。每项测定75x10(-15) 摩尔。使用该测定法,类风湿关节炎患者的滑膜组织提取物与骨关节炎患者的滑膜组织提取物相比,以及与正常胃组织提取物相比,胃肿瘤提取物中的MMP活性增加。

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