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151.
IL-1α及与IL-11、LIF和GDNF联合诱导胚鼠皮质、中脑神经干细胞向多巴胺神经元分化的比较 总被引:1,自引:3,他引:1
为比较皮质和中脑来源的神经干细胞(NSCs)定向分化为多巴胺神经元的情况,应用无血清和单克隆培养技术,分别从皮质和中脑组织中分离克隆、扩增NSCs,然后分成3组诱导分化:①对照组用10%胎牛血清诱导分化;②IL-1α组在10%胎牛血清的基础上加IL-1α诱导分化;③联合因子组在10%胎牛血清的基础上加IL-1α、IL-11、LIF及GDNF进行诱导分化。用酪氨酸羟化酶(TH)免疫组化染色检测多巴胺神经元。在100倍镜下随机取5个视野,计数每个视野中的TH阳性神经元数;并用图像分析软件处理TH阳性神经元的胞体面积和细胞周长;用STATA7.0统计软件进行统计处理。结果显示,皮质对照组中仅见极少的TH阳性神经元(0.25±0.163),中脑对照组中见少量TH阳性神经元(2±0.378);而皮质IL-1α组有较多的TH阳性神经元(15.5±0.866),中脑IL-1α组中的TH阳性神经元则为皮质IL-1α组的150%(22.875±1.517);皮质联合因子组中的TH阳性神经元数(25.75±0.940)与中脑联合因子组中的TH阳性神经元数(28.875±2.125)接近,无显著差异。胞体面积和细胞周长的结果显示出IL-1α组和联合因子组大于对照组、而联合因子组又优于IL-1α组的趋势。上述结果提示,中脑来源的NSCs本身具有一定的分化为多巴胺神经元的区域特异性,而皮质来源的NSCs在IL-1α、IL-11、LIF及GDNF等细胞因子的诱导下可改变其区域特异性而分化为较多较为成熟的多巴胺神经元。 相似文献
152.
Fibroblast growth factor 2 induces differentiation and apoptosis of Askin tumour cells 总被引:7,自引:0,他引:7
Kim MS Kim CJ Jung HS Seo MR Juhnn YS Shin HY Ahn HS Thiele CJ Chi JG 《The Journal of pathology》2004,202(1):103-112
Peripheral primitive neuroectodermal tumour (PNET)/Ewing's sarcoma (ES) and neuroblastoma (NB) are related tumours of neural crest origin with primitive neural characteristics. Fibroblast growth factor 2 (FGF2) is a critical signalling molecule for primitive neural crest cells. The treatment of NB cells with FGF2 variably affects biological characteristics such as growth and differentiation, while in PNET/ES, FGF2 predominantly induces apoptosis. The JK-GMS Askin tumour cell line can be induced to differentiate upon treatment with nerve growth factor (NGF), indicating the integrity of the cellular machinery necessary for differentiation. The present study assesses whether FGF2 can induce differentiation in JK-GMS cells. JK-GMS cells expressed high-affinity FGF receptors (FGFRs), and treatment with FGF2 induced phosphorylation of FGFR1 together with activation of extracellular signal-regulated kinases (ERK1/ERK2) and c-Jun N-terminal kinase (JNK). Subsequent biological effects were growth inhibition, neuronal differentiation, and apoptosis, and these changes were associated with increased expression of neurofilaments, reduction of c-myc and bcl-2 expression, and activation of caspase 3. Treatment of the cells with a specific inhibitor of the MAPK/extracellular signal-regulated kinase (MEK)-1, PD98059, predominantly inhibited the effects of FGF2 on growth, differentiation, and apoptosis, while an inhibitor of JNK reduced apoptosis, indicating that the ERK1/2 and JNK pathways are critical components of FGF2-mediated effects in JK-GMS cells. Additional comparative analyses of FGF2-mediated effects in two ES cell lines (CADO-ES, RD-ES) and a PNET cell line (SK-N-MC) showed pronounced differentiation in SK-N-MC, but not in CADO-ES or RD-ES cells. This study demonstrates that FGF2 can induce neuronal differentiation of PNET including Askin tumour. These findings clearly indicate that the FGF2-mediated signalling pathway plays a critical role in controlling the major properties of PNET cells and may provide a potential therapeutic target for PNET. 相似文献
153.
The present study aimed at investigating the spatial variability of skin temperature (T
sk) measured at various points on the hand during convective and cold contact exposure. A group of 8 subjects participated in a study of convective cooling of the hand (60 min) and 20 subjects to contact cooling of the finger pad (5 min). Experiments were carried out in a small climatic chamber into which the hand was inserted. For convective cold exposure,T
sk was measured at seven points on the palmar surface of the fingers of the left hand, one on the palmar surface and one on the dorsal surface of the hand. The air temperature inside the mini-chamber was 0, 4, 10 and 16°C. With the contact cold exposure, the subjects touched at constant pressures an aluminium cube cooled to temperatures of –7, 0 and 7°C in the same mini-chamber. ContactT
sk was measured on the finger pad of the index finger of the left hand. TheT
sk of the proximal phalanx of the index finger (on both palm and back sides), and of the middle phalanx of the little finger was also measured. The variation ofT
sk between the proximal and the distal phalanx of the index finger was between 1.5 to 10°C during the convective cold exposure to an air temperature of 0°C. Considerable gradients persisted between the hand and fingers (from 2 to 17°C at 0°C air temperature) and between the phalanges of the finger (from 0.5 to 11.4°C at 0°C air temperature). The onset of cold induced vasodilatation (CIVD) on different fingers varied from about 5 to 15 min and it did not always appear in every finger. For contact cold exposure, whenT
sk on the contact skin cooled down to nearly 0°C, the temperature at the area close to the contact skin could still be 30°C. Some cases of CIVD were observed in the contact skin area, but not on other measuring points of the same finger. These results indicated that local thermal stimuli were the main determinents of CIVD. Representative hand skin temperature may require five or more measuring points. Our results strongly emphasised a need to consider the large spatial and individual variations in the prediction and modelling of extremity cooling. 相似文献
154.
Screening microarrays of novel monoclonal antibodies for binding to T-, B- and myeloid leukaemia cells 总被引:3,自引:0,他引:3
Belov L Huang P Chrisp JS Mulligan SP Christopherson RI 《Journal of immunological methods》2005,305(1):10-19
We have developed a microarray (DotScan) that enables rapid immunophenotyping and classification of leukaemias and lymphomas by measuring the capture of cells by immobilized dots of 82 CD antibodies [Belov, L., de la Vega, O., dos Remedios, C.G., Mulligan, S.P., 2001. Immunophenotyping of leukemia using a cluster of differentiation antibody microarray. Cancer Res. 61, 4483; Belov, L., Huang, P., Barber, N., Mulligan, S.P., Christopherson, R.I., 2003. Identification of repertoires of surface antigens on leukemias using an antibody microarray. Proteomics 3, 2147]. The DotScan technology has been used to investigate the properties of 498 new antibodies submitted to the HLDA8 Workshop. These antibodies have been applied as 10 nl dots to a film of nitrocellulose on a microscope slide to make an HLDA8 microarray. After blocking the remaining nitrocellulose surface, individual arrays were incubated with each of 7 cell types from a human leukaemia cell panel consisting of three cell lines, CCRF-CEM (a T-cell acute lymphocytic leukaemia), MEC-1 (derived from B-cell chronic lymphocytic leukaemia) and HL-60 (a promyelocytic leukaemia), and four leukaemias from patients: a T-cell prolymphocytic leukaemia, a B-cell chronic lymphocytic leukaemia, and two acute myeloid leukaemias. Leukaemia cells were captured by those immobilized antibodies for which they expressed the corresponding surface molecule. Unbound cells were gently washed off, bound cells were fixed to the arrays and dot patterns were recorded using a DotScan array reader and quantified using DotScan data analysis software. The data obtained show the unique expression profiles of the 7 cell types in the leukaemia cell panel obtained with the DotScan microarray, and the differential capture patterns for these 7 cell types screened against the 498 antibodies in the HLDA8 microarray constructed for this study. 相似文献
155.
从兔网织红细胞提纯的红细胞分化调节因子(erythroid differentiation factor,EDF),能对体外培养的自发转化成纤维细胞系L929及人鼻咽癌细胞系KB产生作用。当EDF剂量为0.10μg/ml时,可引起L929细胞形态发生改变,并有细胞核固缩现象。第2d的细胞生长抑制率为64.86%,软琼脂集落形成率为0;第5d时细胞增殖为负值。~3H-TdR掺入率明显降低。EDF剂量为0.15μg/ml时,对KB细胞生长已有抑制作用。EDF剂量达0.30μg/ml时,生长抑制明显。以上结果证明了EDF对恶性细胞具有增殖抑制作用。这种作用对不同种类细胞敏感性不同,并且与剂量呈正相关。 相似文献
156.
Antonín Bukovský Michael R. Caudle Jeffrey A. Keenan Jay Wimalasena Nirmala B. Upadhyaya Stuart E. Van Meter 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,36(6):327-341
PROBLEM: We have recently observed that the regression of corpora lutea (CL) in women during the reproductive period of life is accompanied by a diminution of Thy-1 differentiation protein release from vascular pericytes and an accumulation of T lymphocytes and activated macrophages among both degenerating granulosa lutein cells (GLC) and theca lutein cells. These data suggest that the immune system and other stromal factors, representing components of the “tissue control system,” may play a role in regression of the CL. We investigated degenerating CL from climacteric women to address the possibility that the decline of immune functions with advancing age may result in incomplete regression of luteal tissue. This could contribute to the altered hormonal profiles and abnormal uterine bleeding that frequently occur during the climacteric. METHOD: Immunoperoxidase staining and image analysis were used to localize Thy-1 differentiation protein of vascular pericytes, cytokeratin staining of GLC, neural cell adhesion molecule expression by theca lutein cells, CD15 of neutrophils, CD4, CD14, CD68, and leukocyte common antigens of macrophages, and CD3 and CD8 determinants of T lymphocytes. We also investigated the expression of luteinizing hormone receptor (LH receptor) and mitogen activated protein kinases (MAP kinases) in luteal cells. Samples of regressing luteal tissue were obtained during the follicular phase from perimenopausal women (age 45–50) who exhibited prolonged or irregular cycles. For comparison, luteal tissues from women with regular cycles (age 29–45) and CL of pregnancy were also investigated. RESULTS: Corpora lutea of the climacteric women exhibited irregular regression of luteal tissue characterized by a lack of cytoplasmic vacuolization and nuclear pyknosis in GLC, and by a persistence of theca lutein cells exhibiting hyperplasia and adjacent theca externa layers. This was accompanied by a continuing release of Thy-1 differentiation protein from vascular pericytes. Persisting GLC lacked surface expression of macrophage markers (CD4, CD14, CD68 and leukocyte common antigen) as well as nuclear granules exhibiting CD15 of neutrophils, detected in regularly regressing GLC. In addition, such persisting GLC showed weak or no LH receptor expression, and retained the expression of cytokeratin. They also exhibited enhanced staining for MAP kinases. Strong cytoplasmic MAP kinase expression with occasional nuclear translocation was also detected in persisting theca lutein cells, indicating high metabolic activity of these cells. T lymphocytes, although occasionally present in luteal stroma within luteal convolutions, did not invade among persisting GLC and were virtually absent from layers of theca externa and theca lutein cells. CONCLUSIONS: These data indicate that the regressing CL in climacteric women may exhibit persistence of luteal cells, perhaps because of age-induced alterations of the immune system and other local stromal homeostatic mechanisms involved in the elimination of luteal cells. Persisting GLC and/or theca lutein cells may exhibit abnormal hormonal secretion that contributes to the alteration of target tissues, such as the endometrium, resulting in abnormal uterine bleeding, hyperplasia, and neoplasia. 相似文献
157.
158.
目的:研究葛根素(Pur)对脂多糖(LPS)诱导的小鼠急性感染性脑损伤的保护作用及机制。方法:36只清洁级雄性ICR小鼠随机分为正常对照组(NS)、LPS感染组(LPS)和葛根素组(Pur+LPS)。LPS腹腔注射建立急性脑损伤模型,立即腹腔注射给予葛根素注射液治疗,6和24h后旷场。暗场实验检测各组小鼠的自发活动,WesternBlot检测脑组织白细胞分化抗原14(CD14)和环氧化酶2(C0X-2)蛋白表达量,Nisl染色观察神经元存活情况。结果:与NS组相比,LPS组6和24 h旷场实验自主活动距离和穿格次数显著减少,海马神经元的存活数目显著减少,脑组织CD14和C0X-2蛋白表达量显著升高(P<0.05);与LPS组比较,Pur+LPS组6和24 h时海马神经元的存活率明显提高,且CD14和C0X-2蛋白表达量明显下降(P<0.05)。结论:葛根素注射液对LPS所致小鼠急性感染性脑损伤具有一定保护作用,其作用机制可能与抑制脑组织CD14和C0X-2表达有关。 相似文献
159.
张渡淮 《生物医学工程学杂志》1995,12(1):64-66
伊·普利高津的耗散结构理论中,有一个著名的总熵变公式ds=dse+dsi把上述公式用于人体研究,国内外尚未见报导。在前人对人体热力学系统研究的基础上,本文建立了一个人体熵流的数学模型,为进一步展开研究,提供了有力工具并奠定了可靠的理论基础。 相似文献
160.
Shinohara Y Iwasaki H Ota N Nakajima T Kodaira M Kajita M Shiba T Emi M 《Journal of human genetics》2001,46(1):50-51
The nuclear factor kappa-B 2 (NFKB2) gene is a member of the NFKB/Rel gene family, which is known to be a pivotal regulator of the acute phase of the inflammatory
response and of immune responses. We identified three novel single nucleotide polymorphisms (SNPs) and determined their allelic
frequencies, as determined by the sequencing of 48 alleles of the entire gene in a Japanese population sample. Two of the
three polymorphisms were identified at nucleotide (nt) position 1837 (T/C) and nt position, 1867 (GG/G) in the upstream region
of the gene. The other polymorphism was identified at nt position 2584 (G/T) within intron 1. These polymorphisms will be
useful in genetic studies of the processes involved in inflammatory responses and in bone differentiation.
Received: October 17, 2000 / Accepted: October 23, 2000 相似文献