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51.
目的:探讨介入治疗股骨头缺血坏死的临床应用价值。方法:采用Seldinger技术对28例患者行超选择股骨头供血动脉插管,动脉造影、溶通治疗。结果:28例患者治疗后髋部疼痛及关节功能障碍均有不同程度的减轻及改善,有效率96.4%;治疗后病变区血管分支增多、增粗;影像随访显示股骨头骨质不同程度修复。结论:介入治疗具有创伤小、并发症低、血管再通率高、临床症状改善明显的优势,能有效的改善股骨头的局部血液循环和髋关节的疼痛、活动功能,应大力推广。 相似文献
52.
多聚ADP-核糖聚合酶抑制剂对高浓度锌损伤 PC12细胞的保护作用 总被引:2,自引:0,他引:2
探讨多聚ADP-核糖聚合酶(PARP)抑制剂3-氨基苯甲酰胺(3-AB)对400μmo1/L氯化锌损伤PC12细胞的保护作用及其对锌造成的细胞死亡类型的影响.应用MTT法,免疫细胞化学和Western印迹分别测定PC12细胞的存活率和PARP活性;用Hoechst 33342/PI荧光双染色、膜联蛋白V结合实验及DNA断裂分析等方法检测细胞死亡类型.结果表明在400μmol/L氯化锌的作用下,细胞存活率降至(22.7±4.6)%,PARP活性增强,坏死、凋亡和正常细胞百分比分别为(58.4±6.3)%、(18.0±5.6)%及(23.6±4.2)%;3-AB使细胞存活率提高至(76.9±4.7)%,PARP活性减弱,坏死细胞百分数降至(19.2±5.2)%,而正常和凋亡细胞百分数增加到(43.3±1.9)%和(37.5±6.5)%.实验证明,PARP参与了高浓度锌诱导的PC12细胞损伤,抑制PARP活性可提高细胞的存活率,而这种保护作用在于减少细胞的坏死而非凋亡. 相似文献
53.
E. G. Novoselova D. A. Cherenkov O. V. Glushkova T. V. Novoselova V. M. Chudnovsky V. I. Yusupov E. E. Fesenko 《Biophysics》2006,51(3):457-465
The dose dependence of in vitro effects of low-intensity radiation of a He-Ne laser (632.8 nm, 0.2 mW/cm2) on the functional activity of peritoneal macrophages and lymphocytes of mouse spleen was studied. The exposure of isolated cells was varied from 5 to 180 s. If the exposure did not exceed 60 s, stimulation of secretory activity was observed: increased production of interleukin 2, interferon γ, and interleukin 6 in lymphocytes; increased production of tumor necrosis factor α, nitric oxide, and interleukin 6 in macrophages; and enhanced activity of natural killer cells. A longer exposure (up to 180 s) either had no effect on the synthesis of certain cytokines (interleukin 2 in lymphocytes and interleukin 6 in macrophages) or inhibited it, which was expressed in decreased production of interleukin 6 and interferon γ in lymphocytes and nitric oxide in macrophages, as well as in suppression of the activity of natural killer cells. Conversely, the production of interleukin 3 decreased after a short-term exposure but increased after 180-s irradiation. The high sensitivity of cells to extremely weak laser light also manifested itself as a considerable increase in expression of the inducible heat shock protein 70; this effect was observed at all doses studied, including the 5-s exposure. In contrast, expression of the heat shock protein 90 slightly decreased after irradiation of cells with laser light. 相似文献
54.
目的研究肝素酶(Heparanase,Hpa)表达水平与人类肿瘤转移的相关性。方法利用半定量RT-PCR、免疫组织化学(S-P法)和Westernblot检测2组4种不同转移潜能的人类肿瘤细胞系中HpamRNA和蛋白的表达水平。结果HpamRNA和蛋白相对表达量在高转移潜能人类肺癌细胞(0·757±0·033,0·670±0·020)、乳腺癌细胞(0·617±0·024,0·661±0·013)中明显高于相应的低转移潜能肺癌细胞(0·518±0·012,0·406±0·012)、乳腺癌细胞(0·170±0·016,0·227±0·011)。结论在所研究的人类肿瘤中,HpamRNA和蛋白的表达水平与肿瘤的转移能力呈正相关。 相似文献
55.
目的通过对人低分化胃癌细胞系SGC-7901状态和接种细胞数目的研究,建立良好的皮下接种胃癌的动物模型。方法采用腹腔注射SGC-7901细胞,使裸鼠形成腹水;光镜及电镜观察细胞状态;将购买的SGC-7901细胞以及形成腹水后的肿瘤细胞分别以1×108、1×107和1×106个进行裸鼠皮下接种,每组接种5只。观察其肿瘤形成时间、大小、状态及病理学变化。结果SGC-7901细胞接种裸鼠形成腹水后进行培养的肿瘤细胞增殖状态发生改变;购买的SGC-7901细胞以1×108及1×107接种裸鼠,在第21天肿瘤组织中央均出现出血和坏死;1×106的裸鼠第21天未见肉眼可见的肿瘤形成。腹水培养的肿瘤细胞,接种1×108的裸鼠在第21天肿瘤组织中央可见大面积的出血和坏死;接种1×107及1×106的裸鼠在第21天均未见出血和坏死,接种1×107的肿瘤组织体积较大。结论SGC-7901细胞接种裸鼠形成腹水后的细胞,更容易建立SGC-7901细胞皮下接种的胃癌动物模型,其中以接种细胞数为1×107的肿瘤生长较好,更适用于胃癌的实验研究。 相似文献
56.
57.
Susana Solá Ana L. Morgado Cecília M.P. Rodrigues 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Stem cell therapy is a strategy far from being satisfactory and applied in the clinic. Poor survival and differentiation levels of stem cells after transplantation or neural injury have been major problems. Recently, it has been recognized that cell death-relevant proteins, notably those that operate in the core of the executioner apoptosis machinery are functionally involved in differentiation of a wide range of cell types, including neural cells.Scope of review
This article will review recent studies on the mechanisms underlying the non-apoptotic function of mitochondrial and death receptor signaling pathways during neural differentiation. In addition, we will discuss how these major apoptosis-regulatory pathways control the decision between differentiation, self-renewal and cell death in neural stem cells and how levels of activity are restrained to prevent cell loss as final outcome.Major conclusions
Emerging evidence suggests that, much like p53, caspases and Bcl-2 family members, the two prime triggers of cell death pathways, death receptors and mitochondria, may influence proliferation and differentiation potential of stem cells, neuronal plasticity, and astrocytic versus neuronal stem cell fate decision.General significance
A better understanding of the molecular mechanisms underlying key checkpoints responsible for neural differentiation as an alternative to cell death will surely contribute to improve neuro-replacement strategies. 相似文献58.
《Peptides》2013
Little is known about interactions between immune and neuro-endocrine systems in patients with septic shock. We therefore evaluated whether the corticotropin-releasing hormone (CRH) and/or proopiomelanocortin (POMC) derivatives [ACTH, β-endorphin (β-END), β-lipotropin (β-LPH), α-melanocyte stimulating hormone (α-MSH) or N-acetyl-β-END (Nac-β-END)] have any influences on monocyte deactivation as a major factor of immunosuppression under septic shock conditions. Sixteen patients with septic shock were enrolled in a double-blind, cross-over and placebo controlled clinical study; 0.5 μg/(kgbodyweight h) CRH (or placebo) were intravenously administered for 24 h. Using flow cytometry we investigated the immunosuppression in patients as far as related to the loss of leukocyte surface antigen-DR expression on circulating monocytes (mHLA-DR). ACTH, β-END immunoreacive material (IRM), β-LPH IRM, α-MSH and Nac-β-END IRM as well as TNF-α and mHLA-DR expression were determined before, during and after treatment with CRH (or placebo). A significant correlation between plasma concentration of α-MSH and mHLA-DR expression and an inverse correlation between mHLA-DR expression and TNF-α plasma level were found. Additionally, a significant increase of mHLA-DR expression was observed 16 h after starting the CRH infusion; 8 h later, the mHLA-DR expression had decreased again. Our results indicate that the up-regulation of mHLA-DR expression after CRH infusion is not dependent on the release of POMC derivatives. From the correlation between plasma concentration of α-MSH and mHLA-DR expression, we conclude that in patients with septic shock the down-regulation of mHAL-DR expression is accompanied by the loss of monocytic release of α-MSH into the cardiovascular compartment. 相似文献
59.
Jaekyoon Kim Jiyoung Kim Jaesung Shim Siyoung Lee Jisung Kim Soon Sung Lim Ki Won Lee Hyong Joo Lee 《Neurochemistry international》2013
Recent studies have demonstrated that microglial hyperactivation-mediated neuroinflammation is involved in the pathogenesis of several neurodegenerative diseases. Thus, inhibiting microglial production of the neurotoxic mediator tumor necrosis factor-α (TNF-α) is considered a promising strategy to protect against neurodegeneration. Here, we investigated the inhibitory effect of licorice-derived dehydroglyasperin C (DGC) on lipopolysaccharide (LPS)-induced TNF-α production and inflammation-mediated neurodegeneration. We found that DGC pre-treatment attenuated TNF-α production in response to LPS stimulation of BV-2 microglia. DGC pre-treatment attenuated LPS-induced inhibitor of κB-α (IκB-α) and p65 phosphorylation and decreased the DNA binding activity of nuclear factor-κB (NF-κB). DGC pre-treatment also inhibited LPS-mediated phosphorylation of p38 mitogen-activated protein kinases (MAPKs) and extracellular signal-regulated kinase (ERK). Interestingly, DGC treatment of BV-2 microglia significantly increased MAPK phosphatase 1 (MKP-1) mRNA and protein expression, which is a phosphatase of p38 MAPK and ERK, suggesting that the DGC-mediated increase in MKP-1 expression might inhibit LPS-induced MAPKs and NF-κB activation and further TNF-α production. We also found that LPS-mediated microglial neurotoxicity can be attenuated by DGC. The addition of conditioned media (CM) from DGC- and LPS-treated microglia to neurons helped maintain healthy cell body and neurite morphology and increased the number of microtubule-associated protein 2-positive cells and the level of synaptophysin compared to treatment with CM from LPS-treated microglia. Taken together, these data suggest that DGC isolated from licorice may inhibit microglia hyperactivation by increasing MKP-1 expression and acting as a potent anti-neurodegenerative agent. 相似文献
60.
应用RT-PCR、Westem blot、免疫组化分别检测甲状腺乳头状癌组织与癌旁正常甲状腺组织标本中DcR3mRNA及蛋白的表达情况,探讨DcR3在甲状腺乳头状癌组织中的表达及,临床意义。RT-PCR检测显示,甲状腺乳头状癌中DcR3 mRNA的表达明显高于正常甲状腺组织(P〈0.05):Western blot提示,DcR3蛋白在甲状腺乳头状癌中表达比正常甲状腺组织高(P〈0.05);免疫组化显示,DcR3蛋白在甲状腺乳头状癌中高表达(P〈0.05)。DcR3mRNA及蛋白质在甲状腺乳头状癌及正常甲状腺组织间的表达差异有统计学意义(P〈0.05)。DcR3基因及蛋白在甲状腺乳头状癌中高表达,提示DcR3可能促进了甲状腺乳头状癌的发生发展。 相似文献