补肾复方对胸腺细胞增殖周期、胸腺一氧化氮及抗氧化作用的影响

[目的]研究补肾阳复方右归饮和补肾阴复方左归饮在体内对小鼠胸腺细胞增殖周期,胸腺组织一氧化氮和抗氧化作用的影响.[方法]分别采用流式细胞术检测右归饮、左归饮对小鼠胸腺细胞增殖周期、SOD测定试剂盒,NO测定试剂盒检测SOD、NO的含量.[结果]小鼠灌服右归饮后,胸腺细胞的细胞周期较之对照组发生明显的改变,表现为G2/M期细胞的比例明显增加,而G0/G1期细胞的比例明显减少(P＜0.01).而左归饮组小鼠胸腺细胞的细胞周期无明显影响;右归饮组小鼠胸腺组织SOD的活力显著高于对照组,NO的含量则显著低于对照组,而左归饮组则均无显著差异.[结论]右归饮有延缓胸腺衰老的作用,其可能的机制之一是增强胸腺组织的抗氧化能力.     

醋酸甲羟孕酮增强顺铂对人卵巢癌耐药细胞抗癌作用的研究

目的:观察醋酸甲羟孕酮(MPA)对人卵巢癌CoC1/cDDP细胞移植瘤的生长抑制作用及对DDP的耐药逆转作用,并分析其作用机制。方法:建立人卵巢癌裸鼠皮下移植瘤模型,随机分为4组,每组5只。(1)对照组:腹腔注射等体积生理盐水;(2)DDP治疗组:每只每次腹腔注射DDP 3mg/kg。(3)MPA治疗组:每只每次灌胃30mg/kg;(4)联合治疗组:每只每次灌胃MPA 30mg/kg,1h后每只每次腹腔注射DDP 3mg/kg,每隔2天给药1次,共4次,于治疗第1、5、10、15、20天分别测瘤体积,20天后处死裸鼠,完整剥出瘤组织,称瘤重,计算抑瘤率;通过流式细胞仪检测亚G1期细胞及AnnexinV+/PI-细胞鉴定细胞凋亡,分析移植瘤细胞周期;用半定量RT-PCR法检测移植细胞组织Survivin-ΔEx3、caspase-3、P21WAF1/CIP1及GST-π4基因mRNA表达。结果:(1)MPA组、MPA+DDP组治疗第10天起皮下移植瘤体积明显小于DDP组和对照组,且进行性缩小(P<0.01);抑瘤率分别为51.63%、62.21%,均明显大于DDP组的6.84%(P<0.01),并且两组间有显著差异(P<0.01);(2)流式细胞仪分析显示,移植瘤出现亚G1期峰及AnnexinV+/PI-细胞均证实MPA能诱导CoC1/cDDP细胞凋亡,并显著高于对照组及DDP组,并出现G1期阻滞;与DDP合用除出现G1期阻滞外又出现G2/M期阻滞,S期明显减少,亚G1期细胞及AnnexinV+/PI-细胞进一步上升;(3)半定量RT-PCR检测显示,MPA组Survivin-ΔEx3、GST-πmRNA下调,而P21WAF1/CIP1、caspase-3 mRNA上调,与DDP合用后,对Survivin-ΔEx3、P21WAF1/CIP1及GST-πmRNA的表达无协调作用,而对caspase-3 mRNA有协同上调作用。结论:MPA通过阻滞G0/G1期明显抑制了CoC1/cDDP移植瘤生长,并有很强的致凋亡作用,同时下调GST-πmRNA,从而逆转对顺铂耐药。     

铁剥夺抗K562细胞的增殖作用及机制

目的观察铁剥夺对白血病细胞增殖的影响。方法以K562细胞作为人类白血病细胞株,台盼蓝染色,光镜下计数活细胞率;用四甲基偶氮唑蓝（MTT）法测A值（570nm）,绘制生长曲线;流式细胞术分析细胞周期变化。结果小剂量去铁胺（DFO）（12.5μmol/L）处理K562细胞时,生长曲线轻微变化,随时间延长和DFO剂量增加（25、50、100μmol/L）,细胞存活率明显下降,生长曲线高峰显著低于对照组。DFO的抗增殖活性为时间-剂量依赖型。用DFO（50、100μmol/L）处理K562细胞48和72h后,G0/G1期细胞数量增加,S期细胞数量减少,与对照组比较均有显著性差异（Pa〈0.001）。上述作用可被等浓度的三氯化铁抵消。结论铁剥夺具有抗白血病细胞增殖作用,剥夺细胞内铁,阻止细胞由G0/G1期进入S期可能是其机制之一。     

Hair growth-modulation by adrenergic drugs

Since we have recently shown that the beta 2-adrenoreceptor (beta 2-AR) expression of selected regions of the hair follicle (HF) epithelium as well as the number of adrenergic nerve fibers in murine skin change in a hair cycle-dependent manner, this has raised the possibility that adrenergic nerves may exert "trophic" functions during HF cycling. To further explore this concept, we have investigated the effect of neuro-pharmacological manipulations on hair growth (anagen) induction in quiescent telogen mouse skin in vivo. Here, we demonstrate that subcutaneous injections of the noradrenaline (NA)-depleting agent guanethidine, or of the neurotoxin 6-hydroxydopamine, but not of the beta 2-AR agonist isoproterenol induce a premature onset of anagen in the lower back skin of C57BL/6 mice. On day 20 after the start of treatment, more than 80% of the guanethidine-treated mice and ca. 65% of the 6-hydroxydopamine-treated (6-OHDA) mice exhibited premature skin darkening and hair growth at the site of drug application, whereas less than one-third of all control animals showed macroscopic signs of anagen development. This was confirmed by histology, demonstrating mature anagen VI HFs only at the immediate site of treatment with guanethidine or 6-OHDA as opposed to resting telogen HFs in the neighboring untreated skin area. This observation further supports the concept that sympathetic nerves are intimately involved in hair growth control and invites one to explore the neuro-pharmacological manipulation of piloneural interactions as a novel therapeutic strategy for the management of hair growth disorders.     

硫芥诱导Hela细胞发生凋亡及坏死(英文)

目的:研究硫芥诱导Hela细胞凋亡的作用,方法:生长在DMEM培养基中的Hela细胞与不同浓度的硫芥作用3小时,凋亡用电镜,电泳及流式术检测.结果:低浓度硫芥(I μmol·L~(-1))抑制细胞生长;较高浓度(1-100 μmol·L~(-1))使细胞主要在G_1期阻滞,发生典型的凋亡形态改变,提取细胞DNA进行琼脂糖凝胶电泳,出现“DNA Ladder”.流式术观察表明硫芥处理3小时后,细胞撤药培养12小时,凋亡率达33％,S期的细胞最敏感,硫芥1000 μmol-L~(-1)使Hela细胞发生明显的坏死,结论:硫芥诱导Hela细胞发生两种不同的损伤:坏死及凋亡,硫芥的细胞毒有浓度依赖性。     

Estrous cycle patterns of Sprague-Dawley rats during acute and chronic atrazine administration

An increased incidence or earlier onset of mammary tumors (MT) has been associated with lifetime feeding of atrazine, an agricultural herbicide, to Sprague-Dawley (SD) female rats. Because MT occur spontaneously in this strain, along with episodes of persistent estrus and acyclic estrogen secretion, it was proposed that atrazine may act to promote this process. SD female rats, 7 to 8 wks old, were administered atrazine while vaginal cytology was monitored. At 200 mg/kg/d by gavage, which clearly exceeded the maximum tolerated dose (MTD), the predominant early response was prolonged vaginal diestrus. Persistent estrous episodes were seen, but less commonly. When atrazine was added to the diet, there was likewise an initial appearance of prolonged diestrus at 400 ppm, but by 13 to 14 wks on test (20 to 21 wks of age), persistent estrus was predominant, rising to >50% of animals by 26 wks on test. Age-matched controls also displayed persistent estrus, but to a lesser degree. At 400 ppm atrazine for 6 mo, animals displayed vaginal estrus for a mean of 62.8% of all days, versus 47.3% in age-matched controls, and 20 to 25% in young animals. The 400 ppm dose also exceeded the MTD. Observed no-effect levels for estrous cycling and body weight change were 50 ppm. Significant effects on estrous cycling occurred only at levels previously associated with enhanced or premature MT formation, and suggest that the tumor response in aging SD female rats can be manipulated by factors controlling the internal estrogen milieu. Because atrazine has no intrinsic estrogenic activity, it is more likely that high-level dosing to a susceptible animal model alters control of ovulation and normal cycling. The requirement of excessive dosing levels, as well as differences in neuroendocrine senescence, makes a risk to human health from this mode of action essentially nonexistent.     

茶多酚对人鼻咽癌细胞株CNE_2细胞DNA损伤和细胞周期的影响

目的　观察茶多酚（ｔｅａ ｐｏｌｙｐｈｅｎｏｌｓ, ＴＰ） 对人鼻咽癌细胞株ＣＮＥ２ 细胞ＤＮＡ 的损伤作用和细胞周期的影响。方法　用琼脂糖凝胶电泳方法测定ＴＰ对细胞ＤＮＡ的断裂作用;用流式细胞术（ＦＣＭ） 观察ＴＰ对ＣＮＥ２ 细胞周期的变化及其诱导凋亡。结果　ＴＰ可引起ＣＮＥ２ 细胞ＤＮＡ 断裂、其断裂程度随剂量的增加和作用时间的延长而增强。ＴＰ不同浓度和不同作用时间可干扰ＣＮＥ２ 细胞在周期中的进程,使Ｇ１ 期细胞明显增多,Ｓ期细胞减少,细胞分裂增殖指数（ＰＩ）亦随之降低。同时,ＴＰ可诱导ＣＮＥ２ 细胞凋亡,其凋亡率随ＴＰ浓度的增加和作用时间的延长在逐渐增加。结论　ＴＰ１９９８ １２ ０４ 收稿,１９９９ ０７ ３１ 修回＊ 国家自然科学基金资助课题,Ｎｏ ３９３７０８００作者简介：谢冰芬,女,副研究员,硕士生导师,研究方向为肿瘤药理可引起人鼻咽癌细胞株ＣＮＥ２ 细胞的ＤＮＡ 断裂,使细胞停滞于Ｇ１ 期,阻止Ｇ１ 期细胞进入Ｓ期;同时亦可诱导细胞凋亡,这些结果可能为ＴＰ的抗瘤作用提供理论依据     

Rapid induction of p21WAF1 but delayed down-regulation of Cdc25A in the TGF-beta-induced cell cycle arrest of gastric carcinoma cells.

Transforming growth factor-beta (TGF-beta) is a multifunctional polypeptide that inhibits cellular proliferation in most epithelial cells. cdk4 and several cyclin-dependent kinase (cdk) inhibitors (p15INK4B, p21WAF1/Cip1 and p27Kip1) have been implicated in the TGF-beta-induced cell cycle arrest. More recently, down-regulation of Cdc25A, a cdk activator, was additionally suggested as a mechanism underlying growth inhibition by TGF-beta. The existence of diverse cellular mediators of TGF-beta, however, raises the question of whether their involvement might occur in a redundant manner or coordinately in a certain cell type. Using two TGF-beta-sensitive gastric carcinoma cell lines (SNU-16 and -620), we addressed the contributory roles of several cdk inhibitors, and of cdk4 and Cdc25A, in TGF-beta-induced cell cycle arrest by comparing their temporal expression pattern in response to TGF-beta. Among the cdk inhibitors examined, p21 mRNA was most rapidly (in less than 1 h) and prominently induced by TGF-beta. In contrast, p15 mRNA was more slowly induced than p21 in SNU-620 cells, and not expressed in SNU-16 cells harbouring homozygous deletion of p15. Western blotting results confirmed the rapid increase of p21, while opposite patterns of p27 expression were observed in the two cell lines. The down-regulation of Cdc25A mRNA occurred, but was more delayed than that of p15 or p21. Until G1 arrest was established, changes in the protein levels of both Cdc25A and cdk4 were marginal. Co-immunoprecipitation with anti-cdk4 antibody showed that induced p21 associates with cdk4 and that its kinase activity is reduced by TGF-beta, which kinetically correlates closely with G1 arrest following TGF-beta treatment of both cell lines. These results suggest that in certain human epithelial cells, p21 may play an early role in TGF-beta-induced cell cycle arrest, and its cooperation with other cdk inhibitors is different depending on cell type. Delayed down-regulation of Cdc25A and cdk4 may contribute to cell adaptation to the quiescent state in the two gastric carcinoma cell lines studied.     

Predictive value of expression of p16INK4A, retinoblastoma and p53 proteins for the prognosis of non-small-cell lung cancers

The predictive value of expression of p16INK4A, retinoblastoma (Rb) and p53 proteins for prognosis was evaluated in 76 patients with non-small-cell lung cancers (NSCLCs) that were potentially curatively resected between 1990 and 1995, using the results of immunostaining analyses of these proteins as reported in our previous study (Kinoshita et al, 1996). Of these NSCLCs, 22 (29%) lacked p16 protein expression and eight (11%) Rb protein, while 30 (39%) showed positive (altered) p53 protein expression. Survival of patients with p16-negative tumours was not significantly different from that of patients with p16-positive tumours (5-year survival rates 67% and 72% respectively, P = 0.8), nor was survival of patients with Rb-negative tumours significantly different from that of patients with Rb-positive tumours (5-year survival rates 42% and 69% respectively, P = 0.9). Moreover, survival of patients with p16/Rb-negative (either p16- or Rb-negative) tumours was not significantly different from that of patients with p16/Rb-positive (both p16- and Rb-positive) tumours (5-year survival rates 67% and 68% respectively, P = 0.7). In contrast, survival of patients with p53-positive (altered) tumours tended to be shorter than that of patients with p53-negative (unaltered) tumours (5-year survival rates 56% and 78% respectively, P = 0.06). In univariate analysis of potential prognostic factors, p16, Rb and p16/Rb proteins were not significant prognostic factors in the present cohort of potentially curatively resected NSCLCs. Altered p53 protein status tended to be a negative prognostic factor (P = 0.06 by the univariate analysis). These results indicate that loss of p16 protein alone, or in combination with loss of Rb protein, does not predict the clinical outcome of patients with resected NSCLCs.     

食管癌多部位DNA含量分析及其临床意义

目的;探讨食管癌多部位ＤＮＡ含量与临床及病理特性之间的关系。方法：流工细胞光度术检测１００例食管癌手术切除新鲜标本的癌、癌旁和断端组织的ＤＮＡ含量。结果：癌组织ＤＮＡ非整倍体（ＡＮ）、ＤＮＡ指数（ＤＩ）和细胞增殖活性指数（ＰＩ）都显著高于癌旁和断端（Ｐ〈０．０５）;食管癌ＡＮ与肿瘤细胞分化和局部洒巴结转移密切相关（Ｐ〈０．０１）。在癌体与癌旁或断端组织间存在ＤＮＡ倍体异质性（１４．８％）;切距〈５