• 【麻风患者麻风分枝杆菌培养滤液蛋白-10抗体的检测。】 复制标题 收藏 收藏
    DOI:10.1099/jmm.0.46587-0 复制DOI
    作者列表:Parkash O,Kumar A,Nigam A,Girdhar BK
    BACKGROUND & AIMS: :The prevalence of IgG antibodies against Mycobacterium leprae recombinant culture filtrate protein-10 (rCFP-10) was investigated in serum samples from 56 leprosy patients, 15 tuberculosis (TB) patients, 14 other skin-diseased patients and 20 healthy subjects. On classifying the patients into bacterial index (BI)-positive and BI-negative groups, the assay showed 83.3 % (15/18) sensitivity for detection of BI-positive leprosy patients. On the other hand, the sensitivity for detection of BI-negative patients was 18.4 % (7/38). None of the 15 TB patients and 14 other skin-diseased patients was positive; however, only one out of 20 healthy individuals was positive, indicating that antibody response to culture filtrate protein-10 (CFP-10) was highly specific (98.0 %; 48/49). Statistically, the performance of the CFP-10-based assay was found to be comparable (P>0.05) with that of an anti-phenolic glycolipid-I (PGL-I) antibody-detecting assay. Thus, M. leprae CFP-10 is potentially a specific antigen for measuring antibody response in BI-positive leprosy patients. Being a secreted antigen, CFP-10 may act as a marker for the viability of M. leprae inside the host, and hence its serological potential is worth exploring for application in monitoring the response of patients with BI-positive leprosy (a highly infectious form) during the course of chemotherapy. When comparing the bacteriological and serological results, an agreement of 82.1 % showed that seropositivity to M. leprae CFP-10 corresponded well with bacteriological criteria. Hence, CFP-10 seems to be a suitable antigen for classification of leprosy patients into BI-positive and BI-negative groups.
    背景与目标: : 在56名麻风病患者,15名结核病 (TB) 患者,14名其他皮肤病患者和20名健康受试者的血清样本中,研究了针对麻风分枝杆菌重组培养滤液蛋白10 (rCFP-10) 的IgG抗体的患病率。在将患者分为细菌指数 (BI) 阳性和BI阴性组时,该测定显示了检测BI阳性麻风病患者的83.3% (15/18) 敏感性。另一方面,检测双阴性患者的灵敏度18.4% (7/38)。15个TB患者和14个其他皮肤疾病患者中没有一个是阳性的; 然而,20个健康个体中只有一个是阳性的,表明对培养滤液蛋白10 (CFP-10) 的抗体反应是高度特异性的 (98.0%; 48/49)。统计学上,发现CFP-10-based测定的性能与抗-酚糖脂-I (pgl-i) 抗体检测测定的性能相当 (P>0.05)。因此,麻风分枝杆菌CFP-10潜在地是用于测量双阳性麻风病患者的抗体应答的特异性抗原。作为一种分泌的抗原,CFP-10可以作为宿主内麻风支原体生存能力的标志物,因此其血清学潜力值得探索,用于监测双阳性麻风病 (一种高度感染形式) 患者在化疗过程中的反应。当比较细菌学和血清学结果时,82.1% 的一致性表明麻风分枝杆菌的血清阳性CFP-10与细菌学标准非常吻合。因此,CFP-10似乎是用于将麻风病患者分为双阳性和双阴性组的合适抗原。
  • 【使用电纺聚合物支架在三维培养系统中鼠胚胎干细胞的脂肪生成。】 复制标题 收藏 收藏
    DOI:10.1016/j.biomaterials.2006.08.052 复制DOI
    作者列表:Kang X,Xie Y,Powell HM,James Lee L,Belury MA,Lannutti JJ,Kniss DA
    BACKGROUND & AIMS: :A mechanistic understanding of adipose tissue differentiation is critical for the treatment and prevention of obesity and type 2 diabetes. Conventional in vitro models of adipogenesis are preadipocytes or freshly isolated adipocytes grown in two-dimensional (2D) cultures. Optimal results using in vitro tissue culture models can be expected only when adipocyte models closely resemble adipose tissue in vivo. Thus the design of an in vitro three-dimensional (3D) model which faithfully mimics the in vivo environment is needed to effectively study adipogenesis. Pluripotent embryonic stem (ES) cells are a self-renewing cell type that can readily be differentiated into adipocytes. In this study, a 3D culture system was developed to mimic the geometry of adipose tissue in vivo. Murine ES cells were seeded into electrospun polycaprolactone scaffolds and differentiated into adipocytes in situ by hormone induction as demonstrated using a battery of gene and protein expression markers along with the accumulation of neutral lipid droplets. Insulin-responsive Akt phosphorylation, and beta-adrenergic stimulation of cyclic AMP synthesis were demonstrated in ES cell-derived adipocytes. Morphologically, ES cell-derived adipocytes resembled native fat cells by scanning electron and phase contrast microscopy. This tissue engineered ES cell-matrix model has potential uses in drug screening and other therapeutic developments.
    背景与目标: : 对脂肪组织分化的机械理解对于治疗和预防肥胖和2型糖尿病至关重要。常规的脂肪生成体外模型是在二维 (2D) 培养物中生长的前脂肪细胞或新鲜分离的脂肪细胞。仅当脂肪细胞模型与体内脂肪组织非常相似时,才能预期使用体外组织培养模型的最佳结果。因此,需要设计忠实地模仿体内环境的体外三维 (3D) 模型来有效地研究脂肪形成。多能胚胎干 (ES) 细胞是一种自我更新的细胞类型,可以很容易地分化为脂肪细胞。在这项研究中,开发了3D培养系统来模拟体内脂肪组织的几何形状。将鼠ES细胞接种到电纺聚己内酯支架中,并通过激素诱导原位分化为脂肪细胞,如使用一系列基因和蛋白质表达标记以及中性脂质滴的积累所证明的那样。在ES细胞衍生的脂肪细胞中证实了胰岛素反应性Akt磷酸化和 β-肾上腺素能刺激环状AMP合成。通过扫描电子和相差显微镜,从形态上讲,ES细胞衍生的脂肪细胞类似于天然脂肪细胞。这种组织工程的ES细胞基质模型在药物筛选和其他治疗开发中具有潜在用途。
  • 【在小鼠下丘脑器官型培养中,Sequestosome 1 (SQSTM1/p62) 在内质网应激下维持蛋白质折叠能力。】 复制标题 收藏 收藏
    DOI:10.1016/j.neulet.2017.06.014 复制DOI
    作者列表:Tominaga T,Goto M,Onoue T,Mizoguchi A,Sugiyama M,Tsunekawa T,Hagiwara D,Morishita Y,Ito Y,Iwama S,Suga H,Banno R,Arima H
    BACKGROUND & AIMS: :Sequestosome 1 (SQSTM1) also known as ubiquitin-binding protein p62 (p62) is a cargo protein involved in the degradation of misfolded proteins via selective autophagy. Disruption of autophagy and resulting accumulation of misfolded proteins in the endoplasmic reticulum (ER) leads to ER stress. ER stress is implicated in several neurodegenerative diseases and obesity. As knockout of p62 (p62KO) reportedly induces obesity in mice, we examined how p62 contributes to ER stress and the ensuing unfolded protein response (UPR) in hypothalamus using mouse organotypic cultures in the present study. Cultures from p62KO mice showed significantly reduced formation of LC3-GFP puncta, an index of autophagosome formation, in response to the chemical ER stressor thapsigargin compared to wild-type (WT) cultures. Hypothalamic cultures from p62KO mice exhibited higher basal expression of the UPR/ER stress markers CHOP mRNA and ATF4 mRNA than WT cultures. Thapsigargin enhanced CHOP, ATF4, and BiP mRNA as well as p-eIF2α protein expression in both WT and p62KO cultures, but all peak values were greater in p62KO cultures. A proteasome inhibitor increased p62 expression in WT cultures and upregulated the UPR/ER stress markers CHOP mRNA and ATF4 mRNA in both genotypes, but to a greater extent in p62KO cultures. Therefore, p62 deficiency disturbed autophagosome formation and enhanced both basal and chemically induced ER stress, suggesting that p62 serves to prevent ER stress in mouse hypothalamus by maintaining protein folding capacity.
    背景与目标: : Sequestosome 1 (SQSTM1) 也称为泛素结合蛋白p62 (p62) 是一种通过选择性自噬参与错误折叠蛋白降解的货物蛋白。自噬的破坏和内质网 (ER) 中错误折叠的蛋白质的积累导致ER应激。ER应激与几种神经退行性疾病和肥胖症有关。据报道,由于p62 (p62KO) 的敲除会导致小鼠肥胖,因此我们在本研究中使用小鼠器官型培养物检查了p62如何促进下丘脑的内质网应激和随后的未折叠蛋白反应 (UPR)。与野生型 (WT) 培养物相比,来自p62KO小鼠的培养物显示出响应于化学ER应激源thapsigargin的LC3-GFP点形成显着减少,这是自噬体形成的指标。p62KO小鼠的下丘脑培养物显示出UPR/ER应激标记物CHOP mRNA和ATF4 mRNA的基础表达高于WT培养物。Thapsigargin在WT和p62KO培养物中均增强了CHOP,ATF4和BiP mRNA以及p-eIF2α 蛋白的表达,但在p62KO培养物中所有峰值均较大。蛋白酶体抑制剂在两种基因型中均增加了WT培养物中的p62表达,并上调了UPR/ER应激标记物CHOP mRNA和ATF4 mRNA,但在p62KO培养物中更大程度。因此,p62缺乏扰乱了自噬体的形成,并增强了基础和化学诱导的ER应激,表明p62通过维持蛋白质折叠能力来预防小鼠下丘脑的ER应激。
  • 【在2D和3D细胞培养中模拟生理事件。】 复制标题 收藏 收藏
    DOI:10.1152/physiol.00036.2016 复制DOI
    作者列表:Duval K,Grover H,Han LH,Mou Y,Pegoraro AF,Fredberg J,Chen Z
    BACKGROUND & AIMS: :Cell culture has become an indispensable tool to help uncover fundamental biophysical and biomolecular mechanisms by which cells assemble into tissues and organs, how these tissues function, and how that function becomes disrupted in disease. Cell culture is now widely used in biomedical research, tissue engineering, regenerative medicine, and industrial practices. Although flat, two-dimensional (2D) cell culture has predominated, recent research has shifted toward culture using three-dimensional (3D) structures, and more realistic biochemical and biomechanical microenvironments. Nevertheless, in 3D cell culture, many challenges remain, including the tissue-tissue interface, the mechanical microenvironment, and the spatiotemporal distributions of oxygen, nutrients, and metabolic wastes. Here, we review 2D and 3D cell culture methods, discuss advantages and limitations of these techniques in modeling physiologically and pathologically relevant processes, and suggest directions for future research.
    背景与目标: : 细胞培养已成为必不可少的工具,可帮助发现细胞组装成组织和器官的基本生物物理和生物分子机制,这些组织如何发挥作用,以及该功能如何在疾病中被破坏。细胞培养现在广泛用于生物医学研究,组织工程,再生医学和工业实践。尽管平坦的二维 (2D) 细胞培养占主导地位,但最近的研究已转向使用三维 (3D) 结构以及更现实的生化和生物力学微环境进行培养。然而,在3D细胞培养中,仍然存在许多挑战,包括组织-组织界面,机械微环境以及氧气,营养物质和代谢废物的时空分布。在这里,我们回顾了2D和3D细胞培养方法,讨论了这些技术在模拟生理和病理相关过程中的优势和局限性,并提出了未来研究的方向。
  • 【抗微管剂对草履虫细胞培养生长的影响。】 复制标题 收藏 收藏
    DOI:10.1016/S0932-4739(11)80066-0 复制DOI
    作者列表:Pape R,Kissmehl R,Glas-Albrecht R,Plattner H
    BACKGROUND & AIMS: :Since there are no systematic studies available on the effects of anti-microtubule agents on ciliated protozoa, we screened a wide variety of such compounds for their effects on the growth of Paramecium tetraurelia cell cultures. Compounds tested include agents of widely different chemical composition and with reported effects on widely different cell types. We can differentiate between different drug effects: (a) Rotenone is the only agent without any recognisable effect, (b) Another group of compounds (including colchicine) requires very high concentrations, as compared to higher animal cells, i.e., rather close to a cytotoxic level; this group also includes tubulozole (unexpectedly without any difference between the cis- and the trans-stereoisomer). (c) A third group of drugs inhibits cell culture growth without any lethal effects (benzimidazoles, nocodazole, parbendazole; the [anti-]fungal antibiotic, griseofulvin; the herbicide, trifluralin). (d) Finally a group of agents are active in a concentration range also reported for plants (the herbicide, APM) or for higher animal cells (including the microtubule stabiliser, taxol) or for both (vinblastine, vincristine, triethyl lead), although they are cytotoxic at higher concentrations (like compounds of group [b]). Therefore, in particular compounds of group (c) and possibly of group (d) might be considered further on for a more detailed analysis of a possibly genuine anti-microtubular effect in Paramecium cells. Of particular interest may be nocodazole, parbendazole and trifluralin, since they can inhibit cell culture growth (over 24 h tested) in relatively low concentrations (comparable to other cell types) without any impairment of cell viability.
    背景与目标: : 由于尚无关于抗微管剂对纤毛原生动物的影响的系统研究,因此我们筛选了各种此类化合物对草履虫四重草细胞培养物生长的影响。测试的化合物包括化学成分广泛不同的试剂,据报道对细胞类型广泛不同的影响。我们可以区分不同的药物作用 :( a) 鱼藤酮是唯一没有任何可识别作用的药物,(b) 与较高的动物细胞相比,另一组化合物 (包括秋水仙碱) 需要非常高的浓度,即相当接近细胞毒性水平; 该组还包括小管 (出乎意料的是,顺式和反式立体异构体之间没有任何区别)。(c) 第三组药物抑制细胞培养物的生长,而没有任何致死作用 (苯并咪唑,诺考达唑,帕苯达唑; [抗] 真菌抗生素灰黄霉素; 除草剂,氟拉林)。(d) 最后,一组试剂在植物 (除草剂,APM) 或高等动物细胞 (包括微管稳定剂,紫杉醇) 或两者 (长春碱,长春新碱,三乙基铅) 的浓度范围内具有活性,尽管它们在较高浓度下具有细胞毒性 (如 [b] 组的化合物)。因此,特别是可以进一步考虑 (c) 组和 (d) 组的化合物,以更详细地分析草履虫细胞中可能真正的抗微管作用。特别令人感兴趣的可能是诺考达唑,帕苯达唑和三氟拉林,因为它们可以在相对较低的浓度 (与其他细胞类型相当) 下抑制细胞培养物生长 (测试超过24小时),而不会损害细胞活力。
  • 【与已建立的人子宫内膜上皮和基质细胞系共培养对精子运动特性的影响。】 复制标题 收藏 收藏
    DOI:10.1093/humrep/12.6.1197 复制DOI
    作者列表:Guerin JF,Merviel P,Plachot M
    BACKGROUND & AIMS: The effects of co-culture of human spermatozoa with human immortalized endometrial cells - epithelial or stromal - on sperm movement characteristics, including hyperactivation, were studied using computer-assisted sperm analysis (CASA). Epithelial and stromal cell types could be separated following 8-10 days of culture of endometrial cells originating from human biopsies. Both cell types were immortalized by the SV 40 large T antigen. Co-incubation of sperm with epithelial and stromal monolayers enhanced the rate of hyperactivation24.9% (P <0.05) and 17.8% (P = 0.05) versus 9.5% as control, respectively, whereas the majority of motility parameters remained unchanged. Conditioned media had no effect upon sperm parameters, including hyperactivation. Co-incubation with either monolayer was able to maintain sperm motility over a longer period than incubation in control medium alone.

    In four patients whose spermatozoa did not exhibit hyperactivation, co-incubation with epithelial cells, but not conditioned medium, allowed normal rates of hyperactivation (range6.9-15.6%).

    背景与目标: 使用计算机辅助精子分析 (CASA) 研究了人类精子与人类永生化的子宫内膜细胞 (上皮或基质) 共培养对精子运动特征 (包括过度活化) 的影响。在培养源自人活检的子宫内膜细胞8-10天后,可以分离上皮和基质细胞类型。两种细胞类型都被SV 40大T抗原永生化。与9.5% 对照相比,将精子与上皮和基质单层共同孵育可分别提高高激活率24.9% (P <0.05) 和17.8% (P = 0.05),而大多数运动参数保持不变。条件培养基对精子参数 (包括过度活化) 没有影响。与单独在对照培养基中孵育相比,与任一单层共同孵育能够在更长的时间内保持精子活力。
    在四名精子未表现出过度活化的患者中,与上皮细胞共同孵育,但不是条件培养基,允许正常的过度激活率 (范围6.9-15.6%)。
  • 【NIDCR R25赠款支持对研究型非密集型牙科学校的课程和文化的影响。】 复制标题 收藏 收藏
    DOI:10.1177/154405910708600701 复制DOI
    作者列表:Iacopino AM,Pryor ME,Taft TB,Lynch DP
    BACKGROUND & AIMS: :Our objective was to evaluate changes in curriculum and culture within a research non-intensive dental school after implementation of programs supported by the NIH-NIDCR R25 Oral Health Research Curriculum Grant. We designed new curricular elements to foster an appreciation of research/discovery, an interest in academic/research careers, and application of biomedical/clinical advances to patient care. Funding was utilized to develop, implement, and assess a dedicated curricular track of continuous student research/scholarly activity throughout the four years of dental education. This track represented mandatory hours of didactic time exposing students to topics not traditionally included in dental curricula. Additionally, students were provided with customized flexible schedules to participate in elective "hands-on" mentored research/scholarly experiences at local, national, and international sites, including linkages to certificate, MS, and PhD programs. Funding was also used to support a wide array of faculty development activities that provided skill sets required to deliver integrated biomedical/clinical content, research-oriented evidence-based approaches to dental education, and translational case-based teaching methods emphasizing the application of new science/technologies to patient care. We measured changes in student, faculty, and institutional profiles/attitudes using traditional benchmarks, surveys, and focus groups. Comparisons were made between baseline data prior to R25 program initiation and data collected after years 3-4 of program implementation. Significant increases were demonstrated in: (1) student participation in research/scholarship, attendance at national meetings, research awards, publication of manuscripts, pursuit of advanced training/degrees, and expressions of interest in academic/research careers; (2) faculty participation in development activities, publication of manuscripts, and mentoring of students; and (3) increased institutional credibility within the university, supportive infrastructure for research/scholarship, and cultural expectations for academic excellence. Thus, we believe that the R25 programming changed the culture of our dental school, creating a supportive environment for research/scholarship, increasing academic productivity, and altering the attitudes of faculty/students.
    背景与目标: : 我们的目标是在实施nih-nidcr R25口腔健康研究课程补助金支持的计划后,评估非密集型牙科学校课程和文化的变化。我们设计了新的课程元素,以促进对研究/发现的欣赏,对学术/研究职业的兴趣以及将生物医学/临床进展应用于患者护理。在整个牙科教育的四年中,资金用于开发,实施和评估持续的学生研究/学术活动的专用课程。此曲目代表了强制性的教学时间,使学生接触传统上不包括在牙科课程中的主题。此外,还为学生提供了定制的灵活时间表,以参加在本地,国家和国际站点上进行的选修 “动手” 指导的研究/学术经验,包括与证书,MS和博士学位课程的联系。资金还用于支持广泛的教师发展活动,这些活动提供了提供综合生物医学/临床内容所需的技能,以研究为基础的基于证据的牙科教育方法以及强调应用新的案例的基于案例的教学方法。科学/技术用于患者护理。我们使用传统的基准,调查和焦点小组来衡量学生,教师和机构概况/态度的变化。比较了R25计划启动前的基线数据和计划实施3-4年后收集的数据。显着增加的表现是 :( 1) 学生参与研究/奖学金,参加国家会议,研究奖,手稿的出版,追求高级培训/学位以及对学术/研究职业的兴趣表达; (2) 教师参与发展活动,手稿的出版,和指导学生; (3) 提高大学内部的机构信誉,支持研究/奖学金的基础设施以及对学术卓越的文化期望。因此,我们认为,R25编程改变了我们牙科学校的文化,为研究/奖学金创造了支持环境,提高了学术生产力,并改变了教师/学生的态度。
  • 【培养中的胎鼠肺泡II型细胞表达体内发现的几种II型细胞特征,以及主要的组织相容性抗原。】 复制标题 收藏 收藏
    DOI:10.1165/ajrcmb/3.4.325 复制DOI
    作者列表:Oomen LC,Ten Have-Opbroek AA,Hageman PC,Oudshoorn-Snoek M,Egberts J,van der Valk MA,Calafat J,Demant P
    BACKGROUND & AIMS: :Alveolar type II cells were isolated from fetal mouse lung by differential adherence and obtained in monolayer culture. Cultures display a high degree of purity as shown by histochemical and immunocytochemical staining procedures. Seventy-five percent of cells stained positive with specific anti-lavage serum mouse (SALS-M), an antiserum specific for (pre)alveolar type II cells of the mouse, and osmiophilic bodies were present in 82% of cells. These and other characteristics of type II cells in culture correspond to those of alveolar type II cells in fetal mouse lung. The pattern of reactivity of these cells with various anti-cytokeratin antibodies is described, and we show that, in contrast to rat type II cells, they do not exhibit alkaline phosphatase activity. Identity of the type II cell cultures was shown by their specific phospholipid composition and surfactant protein A (SP-A) content. The fetal alveolar type II cells in culture were found to synthesize and express class I but not class II major histocompatibility complex (MHC) antigens. The possibility to culture fetal alveolar type II cells of the mouse and the availability of genetically well-defined inbred and transgenic mouse strains opens ways to study the genetics of type II cell differentiation and function. Also, the in vitro availability of alveolar type II cells, the progenitor cells of mouse lung tumors, will enable us to study in vitro several of the processes involved in lung tumorigenesis in the mouse.
    背景与目标: : 通过差异粘附从胎鼠肺中分离出II型肺泡细胞,并在单层培养中获得。如组织化学和免疫细胞化学染色程序所示,培养物显示出高度的纯度。用特异性抗灌洗液血清小鼠 (sars-M) 染色阳性的5% 个细胞,该血清对小鼠的 (前) 肺泡II型细胞具有特异性的抗血清,和嗜渗体体存在于细胞82% 中。培养的II型细胞的这些和其他特征对应于胎鼠肺中II型肺泡细胞的那些特征。描述了这些细胞与各种抗细胞角蛋白抗体的反应性模式,并且我们表明,与大鼠II型细胞相反,它们不显示碱性磷酸酶活性。II型细胞培养物的身份通过其特定的磷脂组成和表面活性剂蛋白A (sp-a) 含量显示。发现培养物中的胎儿肺泡II型细胞合成并表达I类但不表达II类主要组织相容性复合物 (MHC) 抗原培养小鼠胎儿肺泡II型细胞的可能性以及遗传明确的近交和转基因小鼠品系的可用性为研究II型细胞分化和功能的遗传学开辟了途径。此外,肺泡II型细胞 (小鼠肺肿瘤的祖细胞) 的体外可用性将使我们能够在体外研究与小鼠肺肿瘤发生有关的几个过程。
  • 【pH是通过激活ERK1/2途径控制培养中少突胶质细胞前体分化的细胞内效应子。】 复制标题 收藏 收藏
    DOI:10.1002/jnr.21051 复制DOI
    作者列表:Bernard F,Vanhoutte P,Bennasroune A,Labourdette G,Perraut M,Aunis D,Gaillard S
    BACKGROUND & AIMS: :We reported previously that onset of oligodendrocyte precursor cell (OPC) differentiation is accompanied by an increase in intracellular pH (pH(i)). We show that OPC differentiation is dependent primarily on a permissive pH(i) value. The highest differentiation levels were observed for pH(i) values around 7.15 and inhibition of differentiation was observed at slightly more acidic or alkaline values. Clamping the pH(i) of OPCs at 7.15 caused a transient activation of ERK1/2 that was not observed at more acidic or alkaline values. Furthermore, inhibition of ERK activation with the UO126 compound totally prevented OPC differentiation in response to pH(i) shift. These results indicate that pH(i), acting through the ERK1/2 pathway, is a key determinant for oligodendrocyte differentiation. We also show that this pH(i) pathway is involved in the process of retinoic acid-induced OPC differentiation.
    背景与目标: : 我们以前曾报道过少突胶质细胞前体细胞 (OPC) 分化的开始伴随着细胞内pH(i)) 的增加。我们表明OPC的分化主要取决于允许的pH(i) 值。对于7.15附近的pH(i) 值观察到最高的分化水平,并且在稍微更酸性或碱性值观察到分化的抑制。将OPCs的pH(i) 夹在7.15引起ERK1/2的瞬时活化,这在更酸性或碱性值下没有观察到。此外,用UO126化合物抑制ERK活化完全阻止了响应pH(i) 位移的OPC分化。这些结果表明,pH(i) 通过ERK1/2途径起作用,是少突胶质细胞分化的关键决定因素。我们还表明,该pH(i) 途径参与了视黄酸诱导的OPC分化过程。
  • 【花粉管培养中pH的变化及生长效应。】 复制标题 收藏 收藏
    DOI:10.1016/S0176-1617(84)80045-0 复制DOI
    作者列表:Tupý J,Rhová L
    BACKGROUND & AIMS: :pH 5.9 is optimal for tobacco pollen tube growth in suspension culture. Little pH changes of sugar-mineral medium result from the release of surface-linked compounds from pollen grains. Germination and pollen tube growth bring about a progressive medium acidification resulting in total growth inhibition. An increase of the buffering capacity of the culture medium enhances pollen tube growth. When the pH was kept near the optimum by 25 mM MES-KOH buffer, pollen tubes grew for 4 days and in the presence of casein hydrolysate they reached a length of up to about 4 cm. The growth related acidification of the medium is independent of the presence of mineral cations and is not due to the hydration of respiratory CO(2). It is suggested that it is brought about by proton secretion from pollen tubes.
    背景与目标: : pH 5.9对于悬浮培养中的烟草花粉管生长是最佳的。糖矿物培养基的ph值变化很小,这是由于花粉粒中表面连接的化合物的释放所致。发芽和花粉管生长会导致培养基酸化,从而导致总生长抑制。培养基缓冲能力的增加可增强花粉管的生长。当通过25mmmes-KOH缓冲液将pH保持在最佳值附近时,花粉管生长4天,并且在酪蛋白水解产物存在下,它们达到高达约4厘米的长度。与生长相关的培养基酸化与矿物阳离子的存在无关,而不是由于呼吸CO(2) 的水合作用。建议它是由花粉管的质子分泌引起的。
  • 【血管内皮生长因子在器官培养中刺激胚胎膀胱发育。】 复制标题 收藏 收藏
    DOI:10.1111/j.1464-410X.2006.06215.x 复制DOI
    作者列表:Burgu B,McCarthy LS,Shah V,Long DA,Wilcox DT,Woolf AS
    BACKGROUND & AIMS: OBJECTIVES:To determine whether vascular endothelial growth factor A (VEGF) and its receptors are expressed during bladder development in mice when capillaries are forming, and whether exogenous VEGF might enhance the growth of endothelia and other types of bladder cells, using an embryonic organ-culture model. MATERIALS AND METHODS:Whole bladders from wild-type mice, at embryonic day (E) 14, were grown in serum-free organ culture in an air/5% CO2 atmosphere; some cultures were supplemented with VEGF and/or with VEGF receptor 1/Fc chimera (VEGFR1/Fc), which blocks VEGF bioactivity. Organs were harvested after 6 days and the expression of VEGF and related molecules assessed using immunohistochemistry. RESULTS:VEGF, VEGFR1 and VEGFR2 positive cells were immunodetected in E14 and E18 bladders. Exogenous VEGF increased whole-organ growth, as assessed by explant areas, total cell numbers, DNA and protein content; proliferation was enhanced, and apoptosis decreased, in urothelium and surrounding tissues. VEGF also increased the proportions of cells expressing endothelial (CD31) and smooth muscle (alpha smooth muscle actin) markers. VEGFR1/Fc blocked the growth-enhancing effects of exogenous VEGF. CONCLUSIONS:In organ culture, exogenous VEGF not only stimulated embryonic bladder endothelial cells but also strikingly enhanced the growth of the whole organ. Whether the effects of VEGF on diverse bladder cell populations are direct or indirect requires further investigation. The finding that VEGF protein is present in embryonic bladders in vivo raises the possibility that it has similar actions during normal development. The results also illuminate the pathobiology of certain bladder diseases in which VEGF levels have been shown to be increased.
    背景与目标:
  • 【药用水ech的消化道微生物群的与培养无关的表征揭示了三方共生。】 复制标题 收藏 收藏
    DOI:10.1128/AEM.00356-06 复制DOI
    作者列表:Worthen PL,Gode CJ,Graf J
    BACKGROUND & AIMS: :Culture-based studies of the microbial community within the gut of the medicinal leech have typically been focused on various Aeromonas species, which were believed to be the sole symbiont of the leech digestive tract. In this study, analysis of 16S rRNA gene clone libraries confirmed the presence of Aeromonas veronii and revealed a second symbiont, clone PW3, a novel member of the Rikenellaceae, within the crop, a large compartment where ingested blood is stored prior to digestion. The diversity of the bacterial community in the leech intestinum was determined, and additional symbionts were detected, including members of the alpha-, gamma-, and delta-Proteobacteria, Fusobacteria, Firmicutes, and Bacteroidetes. The relative abundances of the clones suggested that A. veronii and the novel clone, PW3, also dominate the intestinum community, while other clones, representing transient organisms, were typically present in low numbers. The identities of these transients varied greatly between individual leeches. Neither time after feeding nor feeding on defibrinated blood caused a change in identity of the dominant members of the microbial communities. Terminal restriction fragment length polymorphism analysis was used to verify that the results from the clone libraries were representative of a larger data set. The presence of a two-member bacterial community in the crop provides a unique opportunity to investigate both symbiont-symbiont and symbiont-host interactions in a natural model of digestive-tract associations.
    背景与目标: : 对药用水蛭肠道内微生物群落的基于培养的研究通常集中在各种气单胞菌物种上,这些物种被认为是水蛭消化道的唯一共生体。在这项研究中,对16S rRNA基因克隆文库的分析证实了veronii气单胞菌的存在,并揭示了第二个共生体,即Rikenellaceae的新成员clone PW3,在作物内有一个大的隔间,在消化之前会储存摄入的血液。确定了水蛭肠道中细菌群落的多样性,并检测到了其他共生体,包括 α-,γ-和 δ-变形菌,梭菌,厚壁菌和拟杆菌的成员。克隆的相对丰度表明,A. veronii和新型克隆PW3也主导着肠群落,而代表瞬态生物的其他克隆通常以少量存在。这些瞬变的身份在各个水ches之间差异很大。喂食或喂食脱纤维的血液后的时间都不会导致微生物群落主要成员的身份发生变化。末端限制性片段长度多态性分析用于验证克隆库的结果代表较大的数据集。作物中两人细菌群落的存在为在消化道关联的自然模型中研究共生体-共生体和共生体-宿主相互作用提供了独特的机会。
  • 【比较序列分析确定了适应组织培养的人轮状病毒atcc-wa株NSP4细胞毒性域之外的突变,以及其C末端的新的种间可变域。】 复制标题 收藏 收藏
    DOI:10.1007/s007050070056 复制DOI
    作者列表:Mohan KV,Atreya CD
    BACKGROUND & AIMS: :Complete nucleotide sequence of the tissue culture-adapted ATCC-Wa strain of human rotavirus NSP4 was determined. Sequence analysis detected two alternate forms of the gene with a nucleotide difference at position 331 (A or G) in the coding sequence (NSP4-A or NSP4-G) leading to a change from neutral glutamine97 in NSP4-A to a positively charged arginine97 in NSP4-G originating from the same ATCC-Wa preparation. In addition to this, both forms of ATCC-Wa NSP4 revealed three mutations at nucleotide positions 88 (T to C), 142 (C to T) and 572 (G to A), when compared to the previously reported NSP4 sequence from virulent Wa strain. The former two mutations were in the coding sequence and resulted in a leucine16 to serine16 and a proline34 to leucine34 change, while the third mutation was in the 3' non-coding region of the gene. The two amino acid changes may contribute to the 'tissue culture-adaptation' of ATCC-Wa strain. The ATCC-Wa NSP4 sequence was found to differ from the previously reported NSP4 sequence of attenuated Wa strain by lacking a mutation at 133 (T to C), though the mutations at 88 and 142 were present in both strains. Furthermore, comparison of deduced amino acid sequence of NSP4 from human, bovine, porcine and simian rotavirus strains identified a seven-residue (positions 135-141) inter-species variable domain in its C-terminal region.
    背景与目标: : 确定了人类轮状病毒NSP4的组织培养适应的atcc-wa株的完整核苷酸序列。序列分析检测到在编码序列 (NSP4-A或NSP4-G) 中位置331 (a或G) 处具有核苷酸差异的基因的两种替代形式,导致从NSP4-A的中性谷氨酰胺97变为源自相同atcc-wa制剂的NSP4-G中的带正电荷的精氨酸97。除此之外,当与先前报道的来自强毒Wa株的NSP4序列相比时,两种形式的atcc-wa NSP4在核苷酸位置88 (T至C) 、142 (C至T) 和572 (G至A) 处揭示了三个突变。前两个突变在编码序列中,导致亮氨酸16到丝氨酸16和脯氨酸34到亮氨酸34的变化,而第三个突变在基因的3' 非编码区。这两个氨基酸的变化可能有助于atcc-wa菌株的 “组织培养适应”。发现atcc-wa NSP4序列与先前报道的减毒Wa菌株的NSP4序列不同,因为在133 (T至C) 处没有突变,尽管在88和142处的突变存在于两个菌株中。此外,从人,牛,猪和猿猴轮状病毒株中推导的NSP4氨基酸序列的比较确定了其C末端区域中的七个残基 (位置135-141) 种间可变结构域。
  • 【青霉菌S1M29在分批和补料分批培养中增加了纤维素酶和木聚糖酶的产量。】 复制标题 收藏 收藏
    DOI:10.1016/j.biortech.2013.07.124 复制DOI
    作者列表:Dos Reis L,Fontana RC,da Silva Delabona P,da Silva Lima DJ,Camassola M,da Cruz Pradella JG,Dillon AJP
    BACKGROUND & AIMS: :The development of more productive strains of microorganisms and processes that increase enzyme levels can contribute to the economically efficient production of second generation ethanol. To this end, cellulases and xylanases were produced with the S1M29 mutant strain of Penicillium echinulatum, using different concentrations of cellulose (20, 40, and 60 g L(-1)) in batch and fed-batch processes. The highest activities of FPase (8.3 U mL(-1)), endoglucanases (37.3 U mL(-1)), and xylanases (177 U mL(-1)) were obtained in fed-batch cultivation with 40 g L(-1) of cellulose. The P. echinulatum enzymatic broth and the commercial enzyme Cellic CTec2 were tested for hydrolysis of pretreated sugar cane bagasse. Maximum concentrations of glucose and xylose were achieved after 72 h of hydrolysis. Glucose yields of 28.0% and 27.0% were obtained using the P. echinulatum enzymatic extract and Cellic CTec2, respectively.
    背景与目标: : 开发更具生产力的微生物菌株和提高酶水平的工艺可以有助于经济高效地生产第二代乙醇。为此,在分批和补料分批过程中,使用不同浓度的纤维素 (20、40和60g L(-1)),用棘青霉的S1M29突变菌株生产纤维素酶和木聚糖酶。在用40g L(-1) 纤维素补料分批培养中获得最高的FPase (8.3 U mL(-1)) 、内切葡聚糖酶 (37.3 U mL(-1)) 和木聚糖酶 (177 U mL(-1)) 活性。测试了echinulatum酶促肉汤和商业酶Cellic CTec2对预处理的甘蔗渣的水解作用。水解72小时后达到最大浓度的葡萄糖和木糖。分别使用棘皮草酶提取物和Cellic CTec2获得28.0% 和27.0% 的葡萄糖产量。
  • 【自体球体培养: 人脑肿瘤侵袭的筛查工具。】 复制标题 收藏 收藏
    DOI:10.1016/s1040-8428(00)00081-0 复制DOI
    作者列表:de Ridder L,Cornelissen M,de Ridder D
    BACKGROUND & AIMS: :Spheroids are three-dimensional cell aggregates expressing histotypic organisation in vitro comparable to tissue continuity in vivo. They can be prepared from normal tissue and from tumour fragments. In the experiments presented here, dermal human spheroids and brain tumour spheroids are prepared from the same patient. The dermal tissue originates from the border of the incision wound made to effect a stereotactic brain tumour biopsy. The tumour originates from a fragment of the collected stereotactic biopsy. The dermal fragment and the brain biopsy are explanted in vitro to form confluent monolayers. At confluency, the dermal cells are transferred into small Erlenmeyer flasks and rotated at 37 degrees C for 1-2 days and rotation mediated spheroids are formed. Small flaps of the tumour monolayer are placed on a semisolid non-adhesive substrate, reorganise and form agar overlay spheroids. After spheroid formation, a dermal spheroid is confronted with a brain tumour derived spheroid. The confronting pair, after adhering to each other, present an invasion model in vitro. The dermal spheroid functions as the autologous host for the brain tumour spheroid. Putative invasive cells present in the reaggregated brain spheroid will invade the dermal spheroid and destroy it. If no invasive cells are present in the tumour derived spheroid no morphologic changes will be seen in the dermal spheroid; 24 tested brain biopsy spheroids demonstrated a clear correlation between malignancy in situ and invasiveness in vitro. So it can be concluded that the autologous confrontation of brain tumour derived spheroids with dermal spheroids derived from the patient has a predictive value concerning malignant evolution and mimics the situation of the tumour in situ.
    背景与目标: : 球体是三维细胞聚集体,在体外表达组织类型,与体内组织连续性相当。它们可以从正常组织和肿瘤碎片中制备。在这里介绍的实验中,皮肤人球体和脑肿瘤球体是由同一患者制备的。真皮组织起源于切口伤口的边界,以进行立体定向脑肿瘤活检。肿瘤起源于收集的立体定向活检的片段。在体外移植真皮碎片和脑活检以形成汇合的单层。汇合时,将真皮细胞转移到小锥形瓶中,并在37 ℃ 旋转1-2天,并形成旋转介导的球体。将肿瘤单层的小皮瓣放置在半固体非粘附基质上,重组并形成琼脂覆盖球体。球体形成后,真皮球体面对脑肿瘤衍生的球体。相互粘附后,面对的一对在体外呈现入侵模型。真皮球体充当脑肿瘤球体的自体宿主。在重新聚集的大脑球体中存在的假定的侵入性细胞将侵入真皮球体并破坏它。如果肿瘤衍生的球体中没有浸润性细胞,则真皮球体中不会出现形态学变化; 24个经过测试的脑活检球体表明原位恶性肿瘤与体外侵袭性之间存在明显的相关性。因此可以得出结论,脑肿瘤衍生的球体与患者衍生的真皮球体的自体对抗具有有关恶性演变的预测价值,并模仿了原位肿瘤的情况。

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