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51.
John T. Leith 《The Prostate》1994,24(3):119-124
Because there is extremely limited information on the intrinsic radiosensitivity of human prostatic cancer cells, we have investigated the in vitro radiation response of exponentially growing LNCaP cells. Due to the very poor colony-forming potential of the LNCaP cells, radiation survival was investigated using the dose-dependent (0-6 Gy) changes seen after X-irradiation in the shapes of regrowth curves. Survival was described using both the single-hit, multitarget (SHMT) equation and the linear-quadratic (LQ) equation. The values and 95% confidence limits of the extrapolation number (n), quasi-threshold dose (Dq), and mean lethal dose (Do) in SHMT terminology were respectively: 0.9 (0.7-1.0), 0.0 Gy, and 1.39 (0.11) Gy. The LQ alpha and beta parameters were respectively 6.80 (1.13) and -0.53 (2.89). The X-ray dose response of the LNCaP line is, therefore, purely exponential. The mean survival at the clinically relevant dose of 2 Gy (S2) was 51.2% for the LNCaP line. Comparison of the S2 value for the LNCaP line with previous investigations with other human prostatic cancer cell lines (DU145 and PC-3) indicates a mean S2 value of 47.6%, which suggests that human prostate cancer cells might lie toward the resistant side of the spectrum for various classes of human neoplasms. © 1994 Wiey-Liss, Inc. 相似文献
52.
目的 探讨P物质 (SubstanceP ,SP)作用于离体培养的大鼠肉芽组织成纤维细胞后 ,对其表皮生长因子(EGF)及受体 (EGFR)基因表达的影响。方法 采用大鼠肉芽组织成纤维细胞培养和逆转录 聚合酶链反应 (RT PCR)技术 ,观察SP在不同浓度 ( 1× 10 -9~ 1× 10 -5mol/L)及不同孵育时间 ( 0、3、6、12、2 4h)情况下刺激大鼠成纤维细胞后 ,成纤维细胞EGF、EGFRmRNA表达的改变情况。结果 SP可上调大鼠肉芽组织成纤维细胞EGF、EGFRmRNA表达。其中 ,SP对EGF的量 效曲线呈双相分布 ,最大效应浓度为 1× 10 -7mol/L。但SP仅在高浓度时 ( 1× 10 -6~ 1× 10 -5mol/L)促进EGFR表达。在最大效应浓度 ( 1× 10 -7mol/L ,1× 10 -5mol/L)时 ,SP对大鼠成纤维细胞EGF、EGFRmRNA表达的上调作用分别于孵育细胞后 6、12h达高峰。结论 SP对大鼠肉芽组织成纤维细胞EGF、EGFR基因表达存在直接影响 ,其表现形式与SP的刺激浓度及孵育时间有关。这种影响可能是SP在创伤愈合过程中发挥调控作用的生物学机制之一。 相似文献
53.
目的:研究重组人酸性成纤维细胞生长因子(rh-aFGF)对兔创伤的促愈合作用。方法:采用兔背部刀割伤模型,将rh-aFGF溶液隔日一次滴注于创面,用创面照像、透明膜描记称量法记录伤后第4、8、12、16天创面面积,用注水法测量伤腔容积,伤后第8、16天取创面组织,观察创面的病理学变化,包括肉芽组织生长与再上皮化情况。结果:rh-aFGF可明显加速兔皮肤创伤的愈合,使创面面积明显缩小(P<0.05),使伤腔容积明显减少(P<0.05)。组织学检查:rh-aFGF组创面伤后8天成纤维细胞生长活跃、数量多,其毛细血管胚芽与成纤维细胞数量显著多于对照组;伤后16天,创面收缩与再上皮化明显,新生上皮向创面中心爬行较快。结论:rh-aFGF对兔背部刀伤创面有明显的促修复作用。 相似文献
54.
人表皮生长因子与碱性成纤维细胞生长因子纳米缓释剂对成纤维细胞的影响 总被引:3,自引:3,他引:0
目的:制备碱性成纤维细胞生长因子(bFGF)、人表皮生长因子(EGF)可降解缓释微球,考察其生物活性的保存情况,以及它们对成纤维细胞的作用。方法:采用改良的乳化冷凝法交联制备复合bFGF、EGF的明胶缓释微球,将它们加入成纤维细胞的培养液中,用细胞计数法、四甲基偶氮唑盐微量反应比色法(MTT法)测定细胞增殖情况。结果:复合bFGF、EGF的缓释微球平均粒径(11.32±3.64)μm;培养1天后各组细胞计数、吸光度(A)值差异均无显著性;5天后,两种生长因子缓释微球组细胞计数、吸光度(A)值明显高于对照组;7天后,两种生长因子缓释微球组值仍高于其它组,但差异无显著性。结论:复合bFGF、EGF的缓释微球制备工艺简便,成球性好;能较长时间地持续释放活性bFGF、EGF,可促进成纤维细胞的增殖。 相似文献
55.
Yoshito Matsui Tomoatsu Kimura Noriyuki Tsumaki Haruhiko Nakahara Nobuhito Araki Natsuo Yasui Takahiro Ochi 《Journal of orthopaedic science》1996,1(2):130-135
Recent DNA studies performed by several groups have detected mutations of the gene encoding fibroblast growth factor receptor
3 (FGFR3) in patients with achondroplasia-group disorders, including achondroplasia (ACH), hypochondroplasia (HCH), and thanatophoric
dysplasia (TD). For this study, we analyzed theFGFR3 gene in 31 Japanese patients with typical ACH, four with HCH, three with a condition intermediate between ACH and HCH (ACH/HCH-intermediate),
and one with TD. Of the 31 typical ACH patients, 29 showed a G1138 to A transition and the other two a G1138 to C transversion,
both resulting in a common Gly380Arg substitution in the transmembrane domain of FGFR3. The one TD and the four HCH patients
did not display any mutations in the transmembrane domain of FGFR3. Of the three ACH/HCH-intermediate cases, one patient showed
the Gly380Arg substitution and one did not, and further analysis of the second patient revealed the presence of Asn540Lys
substitution. The first patient was, therefore, genotypically diagnosed as ACH and the second as HCH. Peripheral blood leukocyte
DNA analysis in the remaining ACH/HCH-intermediate patient indicated an unequal ratio of mutant to normal PCR products, possibly
representing a somatic mosaic for the Gly380Arg mutation. Analysis of the common FGFR3 mutation thus appears to help in the
molecular diagnosis of patients with achondroplasia-group disorders. 相似文献
56.
目的 探究血清胰岛素样生长因子结合蛋白-3(IGFBP-3)、血小板来源生长因子(PDGF)及碱性成纤维细胞生长因子(bFGF)联合检测对多囊卵巢综合征(PCOS)患者妊娠结局的预测价值。方法 选取2021年5月—2022年12月在沧州市中心医院接受治疗的150例PCOS孕妇作为PCOS组,另选取同期在该院产检健康的90例孕妇作为对照组。比较两组血清IGFBP-3、PDGF及bFGF水平;根据PCOS组孕妇的妊娠情况分为妊娠结局良好组119例和妊娠结局不良组31例,统计PCOS患者妊娠结局情况并比较血清IGFBP-3、PDGF、bFGF水平;绘制受试者工作特征(ROC)曲线分析血清IGFBP-3、PDGF和bFGF对PCOS的预测价值。结果 PCOS组血清IGFBP-3水平低于对照组(P <0.05),PDGF、bFGF水平均高于对照组(P <0.05)。妊娠结局不良组血清IGFBP-3水平低于妊娠结局良好组(P <0.05),PDGF、bFGF水平均高于妊娠结局良好组(P <0.05)。ROC曲线分析结果显示,血清IGFBP-3、PDGF、bFGF水平预测PC... 相似文献
57.
Wen FQ Kohyama T Sköld CM Zhu YK Liu X Romberger DJ Stoner J Rennard SI 《Inflammation》2002,26(6):279-290
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun. 相似文献
58.
G. Chadi A. M?er L. Rosen A. M. Janson L. A. Agnati M. Goldstein S.-O. ?gren R. F. Pettersson K. Fuxe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,97(1):145-158
Basic fibroblast growth factor (bFGF, FGF-2) is a trophic factor for neurons and astrocytes and has recently been demonstrated in the vast majority of dopamine (DA) neurons of the ventral midbrain of the rat. Potential neuroprotective actions of FGF-2 in the l-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) model have also been reported. The actions of the FGF-2 have now been further analyzed in a combined morphological and behavioural analysis in the MPTP model of the adult black mouse, using a continuous human recombinant FGF-2 (hrFGF-2) intraventricular (i.v.t.) administration in a heparin-containing (10 IU heparin/ml) mock cerebrospinal fluid (CSF) solution. Tyrosine hydroxylase (TH) immunocytochemistry in combination with computer assisted microdensitometry demonstrated a counteraction of the MPTP-induced disappearance of neostriatal TH-immunoreactive (ir) nerve terminals following the FGF-2 treatment. Unbiased estimates of the total number of nigral TH ir neurons, using stereological methods involving the optical disector (Olympus), showed that the MPTP-induced reduction in the number of nigral TH ir nerve cell bodies counterstained with cresyl violet (CV; by 56%) was partially counteracted by the FGF-2 treatment (by 26%). The behavioral analysis demonstrated an almost full recovery of the MPTP-induced reduction of the locomotor activity after FGF-2 treatment. This action was maintained also 1 week after cessation of treatment. The hrFGF-2 produced an astroglial reaction as determined in the lateral neostriatum and in the substantia nigra (SN) far from the site of the infusion, indicating that the growth factor may have reached these regions by diffusion to activate the astroglia. Immunocytochemistry revealed FGF-2 immunoreactivity (IR) in the nuclei of the astroglia cell population in the dorsomedial striatum and the microdensitometric and morphometric evaluation demonstrated an increase in the number, but not in the intensity, of these profiles on the cannulated side, suggesting the possibility that hrFGF-2 stimulates FGF-2 synthesis in astroglial cells with low endogenous FGF-2 IR. These results indicate that hrFGF-2, directly and/or indirectly via astroglia, upon i.v.t. infusion exerts trophic effects on the nigrostriatal DA system and may increase survival of nigrostriatal DA nerve cells exposed to the MPTP neurotoxin. 相似文献
59.
目的:为临床研究提供形态学资料。方法:用免疫组化方法,观察碱性成纤维细胞生长因子(bFGF)在糖尿病小鼠视网膜的分布及表达密度;用透射电镜观察不同病程视网膜细胞的损害情况。结果:糖尿病及正常小鼠视网膜各层细胞均表达bFGF,反应强度和密度不同。发病组自6月龄起,居于大血管周围的阳性节细胞密度增加;不同病程bFGF的表达有不同程度的增加。随糖尿病病程延长,细胞超微结构受到不同程度的损害。结论:糖尿病时增多的bFGF直接或间接作用于血管内皮细胞和平滑肌细胞,刺激二者增殖,促进微血管病变的发生;另一方面,减弱视细胞与双极细胞间的信息传递,对糖尿病性盲的发生起重要作用。同时,各种细胞的超微结构及相应的功能也受到不同程度的损害。 相似文献
60.
静态与动态下脱细胞猪主动脉瓣种植人成纤维细胞初步研究 总被引:1,自引:0,他引:1
目的 探索在脱细胞猪主动脉瓣膜材料上种植人成纤维细胞的方法与效果;材料和方法 采用在脱细胞猪主动脉瓣膜材料上静态与动态种植人成纤维细胞,并对其结果进行比较研究。结果 静态种植不能在猪主动脉瓣叶的两侧形成完整的单层人成纤维细胞融合层;而经过动态种植,在一定条件下可以在猪主动脉瓣叶两侧形成完整的单层人成纤维细胞融合层;结论 动态种植较之静态种植易达到形成完整均匀的细胞种植效果。 相似文献