Effects of cerulenin on the endogenous fatty acid synthetic activity in squamous cell carcinoma of the oral cavity.

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.     

高频超声引导定位前臂浅静脉穿刺

目的探讨高频超声引导定位穿刺前臂浅静脉的应用价值。方法对40例常规浅静脉穿刺失败，采用高频探头在同一体表区域寻找并标记浅静脉走行及深度，确认进针方向后再次静脉穿刺，必要时采用实时引导。结果11例经高频超声标记、29例经高频超声实时引导静脉穿刺均一次成功。结论高频超声引导下静脉穿刺的成功率高，无并发症，是一种简便有效的方法，值得在临床推广应用。     

Angiopoietin1/Tie2 and VEGF/Flk1 induced by MSC treatment amplifies angiogenesis and vascular stabilization after stroke.

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.     

川芎嗪拮抗链霉素耳毒性作用及其离子通道机制

目的 研究川芎嗪（tetraethylplyrazine，TMP）拮抗链霉素耳毒性作用及其对耳蜗外毛细胞外向K^＋通道的影响，寻求两者的相关性，旨在探讨川芎嗪拮抗耳中毒作用的离子通道机制。方法 选取豚鼠60只，随机分为6组，即对照组、链霉素组、川芎嗪低浓度组、川芎嗪高浓度组、川芎嗪低浓度＋链霉素组和川芎嗪高浓度＋链霉素组，分别注射生理盐水（2．5ml/kg）、链霉素（450mg／kg）、川芎嗪（12mg／kg）、川芎嗪（60ms／ks）、川芎嗪（12mg／kg）＋链霉素（450mg／kg）、川芎嗪（60mg／kg）＋链霉素（450mg／kg），用药10天后检测各组豚鼠ABR反应阈，并采用全细胞膜片钳技术观察川芎嗪对耳蜗外毛细胞Ca^2＋敏感K^＋电流和延迟外向K^＋电流的影响。结果 结果表明川芎嗪明显降低链霉素所致的豚鼠ABR反应阈升高，提示川芎嗪具有明显的拮抗链霉素耳毒性作用；川芎嗪能明显增大豚鼠耳蜗外毛细胞Ca^2＋敏感K^＋电流和延迟外向K^＋电流，并呈浓度依赖关系。结论 川芎嗪可能通过增大K^＋通道电流而发挥其降低链霉素耳毒性作用，推测这是其抗耳毒性作用机制之一。     

富氧对海拔3700m高原人体运动心力储备的影响

目的　探讨富氧对高原人体运动心力储备方面的影响。方法　对海拔 3 70 0m高原的 1 2名健康青年富氧 (氧浓度为 2 4%～ 2 5 %)前后分别进行踏阶运动 ,采用心力监护仪采集和记录心动周期和心力信息 ,把完成规定运动量运动后第一心音 (S1 )幅值对安静时S1 幅值增加的相应倍数评估心肌收缩能力储备指数 (CCRI) ;利用舒张期和收缩期时限数据计算舒张期 /收缩期比值 (D/S比 )。结果　运动后较安静时HR ,D/S ,S1 幅值均增高 ,有非常显著性差异 (P <0 .0 1 ) ;富氧运动较未富氧运动CCRI,D/S ,S1 幅值增高 ,有显著性差异 (P <0 .0 5 ) ,HR无统计学意义 (P >0 .0 5 )。结论　高原低氧环境下心脏储备主要是心肌收缩能力储备而不是心率储备。富氧对增强机体心力储备具有重要作用     

Effect of N-tosyl-L-phenylalanylchloromethyl Ketone on Tumor Necrosis Factor-alpha -induced NF-κB Activation and Apoptosis in U937 Cell Line

Summary: To investigate the effect of N-tosyl-L-phenylalanylchloromethyl ketone (TPCK) on tumor necrosis factor-alpha-induced NF-κB activation and apoptosis in U937 cell line, changes and subcellular localization of NF-κB/p65 and IκB-α were observed by fluorescencemicroscopy and expression and degradation of IκB-α by flow cytometry. The apoptosis of U937 cells was measured by flow cytometry and electrophoresis of DNA. Immunolfluorescence assay showed that NF-κB/p65,IκB-α only localized in cytoplasm. After TNF-α stimulation, p65 was localized only in nuclei, and IκB-α was only localized in cytoplasm and decreased. The changes of TNF-α stimulation were specifically inhibited by TPCK. Flow cytometry also revealed the downregulation of IκB-α protein during TNF-α-induced apoptosis and the down-regulation was specifically inhibited by TPCK. Flow cytometry also showed the apoptosis of U937 cells after TNF-α induction. DNA ladder can be detected in cells treated by TNF-α. It is concluded that degradation of IκB-α protein and NF-κB/p65 translocation occur during TNF-α-induced apoptosis of U937 cells, suggesting the activation of NF-κB.TPCK-sensitive protease plays an important role in the degradation of IκB-α protein induced by TNF-α in U937 cells. TPCK sensitive protease also plays an important role in the apoptosis of U937 cells induced by TNF-α.     

CT影像学评分预测急性胰腺炎病情及转归的研究

目的 探讨CT影像学评分对急性胰腺炎病情和转归的预测价值。方法 回顾性分析入院后经CT检查的急性胰腺炎46例，按一定的规则对每例患进行CT影像学评分与分型，并与临床治疗中的有关资料进行对照。结果 46例患CT评分后获得：轻型24例，中型13例，重型9例。轻型患较重型住院日少、恢复顺利，中转手术及死亡率均以重型为高。结论 CT评分对急性胰腺炎病情及预后评估具有重要意义。     

应用气相色谱法鉴别海南省大劣按蚊

大劣按蚊是海南省疟疾的主要传播媒介。本文应用气相色谱法,分析海南省不同地区、不同季节大劣按蚊的皮质烃类。经统计学分析,它们的成分无显著性差异。应用聚类分析法,它们的距离系数很接近。提示海南省的大劣按蚊很可能是同一种。     

X射线照射量(治疗水平)标准装置的研究和建立

Ｘ射线照射量（治疗水平）标准装置是由标准剂量仪，Ｘ射线照射源，测量车、定位系统及其辅助设备组成，本文作者主要介绍标准装置各个部分的构成及技术参数，该标准装置于１９９１年通过国家技术监督局认证，尔后，正式开展放射仪表的检定和校准工作。