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11.
Chuan-Bin Guo Nian-Hui Cui Guang-Yan Yu Ding-Xin Liu Shu-Cong Meng Qing Song 《Journal of oral and maxillofacial surgery》2003,61(8):909-912
PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs. 相似文献
12.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献
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In this paper, 34 samples, 25 from 18 cervical carcinoma patients and 9 from 8 non-cervical carcinoma patients, were assayed using (alpha-32P) dCTP HSV-2 DNA probe and nucleic acid hybridization technic. It was shown that the positive rates of HSV-2 DNA corresponding sequence were 50% (2/4), 36% (5/14) and 12% (1/8) in the in situ cancer, invasive cancer and non-cervical cancer tissues. No HSV was isolated from 7 cancer specimens which showed a positive reaction by nucleic acid hybridization. 相似文献
17.
止血灵(暂定名)是由尖吻腹蛇(Deina Agkistrodon acutus)蛇毒分离提取得到的一种类凝血酶组分,具有明显的促凝(止血)作用,我科自1992年10月~1993年10月使用广州蛇毒研究所与广州医学院血液学研究 相似文献
18.
刺梨汁对慢性氟中毒的影响及机理研究 总被引:1,自引:0,他引:1
用高氟饲料喂养大鼠6个月,复制出慢性氟中毒模型,再自由饮用刺梨汁3个月,探讨刺梨汁对慢性氟中毒的影响及机理。结果表明:刺梨汁可明显改善氟中毒的一般状况,对已形成的氟斑牙影响不大,但可促进尿氟排泄,降低血清和骨氟含量及尿羟脯氦酸含量,提高血清中维生素C、维生素E和血清、肝、肾GSH含量,增强血、肝、肾GSH-Px和SOD活性,降低血清、肝和肾LPO含量,降低尿γ-GT和血清GPT活性及肝TG含量,提示:刺梨汁具有明显桔抗慢性氟中毒作用,其机理可能是通过促进尿氟排泄和抗氧化作用。 相似文献
19.
目的观察由黄芪、白术、淫羊藿组成的复方制剂(壮骨肾宝)对实验性小鼠高脂血症的影响。方法用蛋黄乳液快速致小鼠单纯性高胆固醇血症和喂养高脂饲料致高脂血症模型 ,观察预防性给予不同剂量的壮骨肾宝后对血清总胆固醇(TC)、甘油三酯(TG)和高密度脂蛋白胆固醇(HDL -ch)的影响。结果壮骨肾宝中、高剂量能使血清TC降低(P<0.05),HDL -ch升高(P<0.01) ,但对TG的影响不大。结论壮骨肾宝有一定降血脂作用 ,并与剂量有关 相似文献
20.
中国蒙,汉族酒依赖与醇脱氢酶和醛脱氢酶基因多态性的相关研究 总被引:7,自引:1,他引:6
为探讨醇脱氢酶(ADH)基因和醛脱氢酶(ALDH)基因多态性与酒依赖患病的相互关系,用耳血干血痕聚合酶链反应、等位基因特异性寡核苷酸探针方法,检测乙醇代谢酶ADH和ALDH基因型在我国蒙、汉民族酒依赖与非酒依赖者中分布频率。结果显示在酒依赖组(汉族52例,蒙族31例)与正常对照组(汉族48例,蒙族35例)之间:汉族的ALDH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01),而蒙族则表示为ADH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01)。这提示汉族酒依赖的发病与ALDH2基因有关,蒙族则与ADH2基因有关。 相似文献