伊贝碱甙B的分离和结构测定

本文报道自吉林栽培的伊贝母(Fritillaria pallidiflora Schrenk)中分得一种新的C-去甲-D-异甾体生物碱甙,命名为伊贝碱甙B(yibeinoside B)。根据红外、质谱、氢谱和碳谱确定了结构。     

钙拮抗剂TMB-8抑制BHQ,NE和KCl引起的培养乳牛基底动脉单个平滑肌细胞内游离钙的升高

用ＡＲＣＭＭＩＣ阳离子测定系统，测量单个细胞内游离钙浓度（［Ｃａ２＋］ｉ），研究８（Ｎ，Ｎ二乙胺）ｎ辛基３，４，５三甲氧基苯甲酸酯（ＴＭＢ８）对培养乳牛基底动脉平滑肌［Ｃａ２＋］ｉ的作用。在细胞外钙浓度为１３ｍｍｏｌ·Ｌ－１时，ＴＭＢ８（３０μｍｏｌ·Ｌ－１）可明显抑制ＢＨＱ，ＮＥ及ＫＣｌ引起［Ｃａ２＋］ｉ的升高。在细胞外钙为零＋ＥＧＴＡ０１ｍｍｏｌ·Ｌ－１时，ＴＭＢ８（１０，３０及１００μｍｏｌ·Ｌ－１）可浓度依赖性地降低静息［Ｃａ２＋］ｉ，ＴＭＢ８（３０μｍｏｌ·Ｌ－１）可几乎完全阻断ＢＨＱ及ＮＥ引起［Ｃａ２＋］ｉ的增加。研究表明ＴＭＢ８降低培养乳牛基底动脉平滑肌［Ｃａ２＋］ｉ的机制，主要是抑制肌浆网Ｃａ２＋的释放，或增加肌浆网对Ｃａ２＋的摄入，并由此间接地抑制细胞外钙的内流。     

利用核酸外切酶Ⅲ体外缺失法构建PTLIL-2△n系列缺失质粒

PTLIL-2是一个含有人白细胞介素2(interleukin-2,IL-2)cDNA克隆的细菌质粒,含有该质粒的宿主菌虽然表达IL-2,但表达效率不理想。我们利用核酸外切酶在Ⅲ(exonucleaseⅢ,ExoⅢ),采用两种不同的方法,缺失IL-2 cDNA 3′端非编码顺序,获得了含有IL-2片段长度不同的系列缺失质粒PTLIL-2△n;并从中筛选出数个较高效表达IL-2的质粒。该两法简便易行,在基因工程领域中有一定推广价值。     

Mechanism of the production of the negative endocochlear DC potential in the guinea pig

Changes in endocochlear DC potential (EP) and potassium ion concentrations in endolymph were measured simultaneously during anoxia or during perfusion of the perilymphatic space with furosemide, 10(-2)M, in normal and kanamycin-deafened guinea pigs. The potassium ion conductance (Gk) through the cochlear partitions was calculated. Thirty minutes after the onset of anoxia, the Gk is 22.1 microM/min/mV in normal guinea pigs and 4.8 microM/min/mV in kanamycin-deafened guinea pigs. At that time the EP is -29.5 mV in normal guinea pigs and 1.4 mV in kanamycin-deafened guinea pigs. In the early stage of anoxia the rate of potassium ion concentration decrease in the endolymph per unit time is greater in normal guinea pigs than in kanamycin-deafened guinea pigs. These results suggest a rapid increase in the permeability of potassium ions in the organ of Corti in the early stage of anoxia might produce a large negative potassium ion diffusion potential or negative EP in normal guinea pigs and the failure to develop the negative EP in kanamycin-deafened guinea pigs might be due to the lack of such a rapid increase in the permeability because of the loss of the hair cells.     

Kalman滤波分光光度法同时测定多相脂质体口服液中氟尿嘧啶和尼泊金的含量

本文提出了对测量值平滑后,用Kalman滤波分光光度法同时测定多相脂质体口服液中氟尿嘧啶和尼泊金的含量,改善了滤波效果,较好地解决了复杂基质存在下多组分的同时测定。用人工合成样考察表明,在269～273nm间滤波结果较好。用分别相当制剂标示量80,100,120%的两组分九种可能组合人工合成样品考查结果表明,氟尿嘧啶和尼泊金的回收率分别为99.3～102.6%和97.8～103.0%;当存在系统误差时,回收率分别为99.4～102.7%和97.0～102.9%     

96孔板微生物法微量测定血浆和红细胞内叶酸含量

目的　了解正常人血浆和红细胞内叶酸含量。方法在 96孔细胞培养板中应用L .casie和叶酸培养基对 59例健康青年人的血浆和红细胞内叶酸含量进行微量测定。结果血浆叶酸含量为 (8 2± 2 9) μg L ;红细胞内叶酸含量为 (337 5± 91 0 ) μg L。批内试验 :(1 2 4± 0 3) μg L ,CV =2 2 % ;批间试验 :(1 3 3± 0 6) μg L ,CV =4 7%。平均回收率 1 0 0 1 %。结论 96孔板微生物法微量测定叶酸其方法准确、灵敏度高、重复性好 ,操作简便、样本量微 ,适用于各种生物组织样本的检测     

DNA vaccines and allergic diseases

1. Allergic diseases are characterized by inappropriate immune responses to common environmental antigens. The prevalence of these diseases has been increasing worldwide for reasons that are not exactly clear. 2. Current treatment is largely symptomatic. Because the initial observation that simple plasmid DNA injections resulted in in vivo protein expression and induction of adaptive immune responses to the encoded antigen, the potential of modifying the allergic immune responses by DNA vaccination so as to treat and prevent these diseases has been explored extensively. 3. In the present paper we review preclinical studies using animal models of allergic diseases, with an emphasis on DNA vaccine design, for house dust mite allergens-related allergic asthma.     

9－（2－膦酰甲氧乙基）腺嘌呤及其位置异构体3－（2－膦酰甲氧乙基）腺嘌呤的合成和抗病毒活性研究

９－（２－膦酰甲氧乙基）腺嘌呤及其位置异构体３－（２－膦酰甲氧乙基）腺嘌呤的合成和抗病毒活性研究刘晓辉，王琳，贯宝和，孔漫，张兴权，陶佩珍，陈鸿珊（中国医学科学院、中国协和医科大学药物研究所，北京１０００５０；中国医学科学院、中国协和医科大学医药生物...     

HPLC法同时测定注射用甲氧异腈中FSA和MIBI的含量

目的 :采用RP HPLC法同时测定了注射用甲氧异腈中两种主要成份二氧硫脲 (FSA)和四 (甲氧基异丁基异腈 )络铜 (I)氟硼酸盐 (MIBI)的含量。方法 :以甲醇、磷酸二氢铵 ( 80∶2 0 )为流动相 ,检测波长 2 1 5nm ,HPLC法测定含量。结果 :试验表明 ,FSA和MIBI在 2 5～ 1 2 5μg/ml,50～ 2 50 μg/ml范围内呈良好的线性关系 ,回归方程分别为Y =0 .2 3 0 .0 2X(r =0 .994 6) ,Y =-2 .1 9 0 .0 3X(r =0 .9998) ,相对标准偏差分别为 1 .2 5%和 0 .4 2 %。结论 :该方法简便、准确、可靠     

Redox-sensitive iodinated polymersomes carrying histone deacetylase inhibitor as a dual-functional nano-radiosensitizer for enhanced radiotherapy of breast cancer

Radiotherapy (RT) is a frequently used means in clinical tumor treatment. The outcome of RT varies, however, to a great extent, due to RT resistance or intolerable dose, which might be resolved by the development of radio-sensitizing strategies. Here, we report redox-sensitive iodinated polymersomes (RIP) carrying histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA, vorinostat), as a new dual-functional nano-radiosensitizer for breast cancer radiotherapy. SAHA-loaded RIP (RIP-SAHA) with a size of about 101 nm exhibited good colloidal stability while the reduction-activated release of SAHA, giving rise to better antitumor effect to 4T1 breast carcinoma cells than free SAHA. Accordingly, RIP-SAHA combined with a 4 Gy dose of X-ray radiation led to significantly enhanced suppression of 4T1 cells compared with SAHA combined 4 Gy of X-ray radiation, as a result of enhanced DNA damage and impeded DNA damage repair. The pharmacokinetics and biodistribution studies by single-photon emission computed tomography (SPECT) with ¹²⁵I-labeled SAHA (¹²⁵I-SAHA) showed a 17.3-fold longer circulation and 237.7-fold better tumor accumulation of RIP-SAHA over SAHA. The systemic administration of RIP-SAHA greatly sensitized radiotherapy of subcutaneous 4T1 breast tumors and brought about significant inhibition of tumor growth, without causing damages to major organs, compared with radiotherapy alone. RIP not only enhanced SAHA delivery but also acted as a radiosensitizer. RIP-SAHA emerges as a smart dual-functional nano-radiosensitizer to effectively enhance tumor radiotherapy.