Recent advances in preclinical in vitro approaches towards quantitative prediction of hepatic clearance and drug-drug interactions involving organic anion transporting polypeptide (OATP) 1B transporters

Hepatic uptake mediated by organic anion transporting polypeptide (OATP) 1B1 and 1B3 can serve as a major elimination pathway for various anionic drugs and as a site of drug-drug interactions (DDIs). This article provides an overview of the in vitro approaches used to predict human hepatic clearance (CL_h) and the risk of DDIs involving OATP1Bs. On the basis of the so-called extended clearance concept, in vitro–in vivo extrapolation methods using human hepatocytes as in vitro systems have been used to predict the CL_h involving OATP1B-mediated hepatic uptake. CL_h can be quantitatively predicted using human donor lots possessing adequate OATP1B activities. The contribution of OATP1Bs to hepatic uptake can be estimated by the relative activity factor, the relative expression factor, or selective inhibitor approaches, which offer generally consistent outcomes. In OATP1B1 inhibition assays, substantial substrate dependency was observed. The time-dependent inhibition of OATP1B1 was also noted and may be a mechanism underlying the in vitro–in vivo differences in the inhibition constant of cyclosporine A. Although it is still challenging to quantitatively predict CL_h and DDIs involving OATP1Bs from only preclinical data, understanding the utility and limitation of the current in vitro methods will pave the way for better prediction.     

二十四员大环双核铜(Ⅱ)配合物的合成及其对超氧化物歧化酶的模拟--Ⅱ配合物的歧化超氧离子的活性

用核黄素光照法测定自合成的2，6-二乙酰基吡啶缩3-氧杂戊烷1，5-二胺大环，H20、im^-、N3^-及SCN^-为桥基的双核铜（Ⅱ）配合物的超氧化物歧化酶活性，它们均在10^-5-10^-7mol/L的浓度范围内具有50%以上抑制率。     

从自由基生物学角度评价鸡肉质量的实验研究

本文把外观健康和非健康的活鸡各20只分成两组,宰后测其肝、腿肌中超氧化物歧化酶(SOD)含量和脂质过氧化产物丙二醛(MDA)水平,发现两组中上述指标值差异显著(P<0.050 ;同时对两组实验鸡胴体在宰后4小时做了感官鉴别,也判断出其品质存在差异。提示体内SOD活性和MDA水平可以反映鸡肉质量,比感官鉴别更具敏感性,同时也可以反映宰前鸡的健康状况。     

Ex vivo neutrophil function in response to three different doses of glycosylated rHuG-CSF (Lenograstim)

Granulocyte colony-stimulating factor (G-CSF) is being considered as adjuvant treatment for infections in non-neutropenic patients. Normal healthy donors were given rHuG-CSF (Lenograstim) at 2.5, 5.0 and 7.5 μg/kg subcutaneously daily for 5 d. Polymorphonuclear leucocyte (PMN) function tests were carried out on peripheral blood PMN before the first injection and at 24 h and 96 h. Circulating PMN levels were also measured at these time intervals and found to be significantly increased with all doses by 24 and 96 h. Investigation of cell surface antigen expression revealed no changes in β₂ integrin (CD11b/CD18) expression. L-selectin (CD62L) expression was reduced with all doses by 96 h, this being significant with the 7.5 μg/kg dose. FcγRI (CD64) levels were significantly up-regulated with the 7.5 μg/kg dose by 96 h whereas FcγRIII (CD16) expression was found to be reduced during G-CSF treatment. Superoxide anion production was significantly increased in response to N -formylmethionylleucylphenylalanine (FMLP) and opsonized Staphylococcus epidermidis stimulation at 24 h and 96 h with the 5.0 and 7.5 μg/kg doses. The initial rate of phagocytosis (0–2 min) appeared to have increased with the 7.5 and 5.0 μg/kg doses at 96 and 24 h compared with PMN responses pretreatment, although these increases were not statistically significant. These results show that G-CSF enhances the functional responses of PMN stimulated by physiological agonists and may help in the treatment of infections.     

Changes of circulating TNF and its effects on Pseudomonas aeruginosa septic shock in rabbits

Itiswellknownthatcertaincytokinesplayapivotalroleinthedevelopmentoftraumaandshock.Tumornecrosisfactor(TNF)isapolypep-tiedcytokinesynthesizedinmonocytesandmacrophagesinresponsetolipopolysaccharide(LPS)stimulation-TherelationshipbetweenTNFandendotoxic-septicshockbecomesafocusoftheresearchofshockmediators[1'2].Alargeamountofexperimentalandclinicaldata[3-9JsuggestthatTNFplaysanimportantroleinthepathogenesisofendotoxic-septicshockbuttheprecisemechanismandtherelationshipofTNFtoshockseverityrem…     

SOD-like Activity of Copper Salicylate Complex in Tween Micel-lar Systems

合成了水杨酸铜络合物并分析了其组成，提纯了Ｔｗｅｅｎ－２０，－４０，－６０，－８０，并测定了它们在ｐＨ７．４的磷酸缓冲液中的ＣＭＣ。用Ｃｙｔ．ｃ还原法分别测定了水杨酸铜络合物在不同介质中的ＳＯＤ样活性。详细研究了表面活性剂与水杨酸铜络合物协同清除Ｏ－２的作用。观察到在胶束体系中水杨酸铜络合物的ＳＯＤ样活性明显高于缓冲液体系无表面活性剂时的ＳＯＤ样活性，表面活性剂本身也具有清除Ｏ－２的功能。抗红细胞膜脂质过氧化实验也得到类似结果。这可用胶束催化解释。水杨酸铜－Ｔｗｅｅｎ体系可能是一种潜在的抗炎药物。     

一氧化氮含量在急性脑梗死不同时期变化的临床意义

目的和方法为探讨急性脑梗死不同时期一氧化氮（NO）含量变化的临床意义，送检42例急性脑梗死患者不同时期的血清，采用Green改良法检测NO和以邻苯三酚自氧化法检测超氧化物歧化酶（SOD）含量，并配有30例正常对照。结果结果表明：脑梗死早期NO、SOD含量显著降低；急性期NO含量增高，并超过正常对照，而SOD含量进一步下降；脑梗死稳定期后，NO含量有所下降，接近正常水平，SOD含量增高，但仍低于正常。结论据上述结果提示，NO在急性脑梗死不同时期具有细胞毒性和组织保护双重作用，为临床寻求一种急性脑梗死的可能有效治疗方法提供了理论依据。     

Characterization of a highly polymorphic marker adjacent to the SLC4A1 gene and of kidney immunostaining in a family with distal renal tubular acidosis.

BACKGROUND: Mutations in the human SLC4A1 (AE1/band 3) gene are associated with hereditary spherocytic anaemia and with distal renal tubular acidosis (dRTA). The molecular diagnosis of AE1 mutations has been complicated by the absence of highly polymorphic genetic markers, and the pathogenic mechanisms of some dRTA-associated AE1 mutations remain unclear. Here, we characterized a polymorphic dinucleotide repeat close to the human AE1 gene and performed an immunocytochemical study of kidney tissue from a patient with inherited dRTA with a defined AE1 mutation. METHODS: One CA repeat region was identified in a phage P1-derived artificial chromosome (PAC) clone containing most of the human AE1 gene and the upstream flanking region. We determined its heterozygosity value in multiple populations by PCR analysis. Genotyping of one family with dominant dRTA identified the AE1 R589H mutation, and family member genotypes were compared with the CA repeat length. AE1 and vH(+)-ATPase polypeptides in kidney tissue from an AE1 R589H patient were examined by immunocytochemistry for the first time. RESULTS: This CA repeat, previously reported as D17S1183, is approximately 90 kb upstream of the AE1 gene and displayed considerable length polymorphism, with small racial differences, and a heterozygosity value of 0.56. The allele-specific length of this repeat confirmed co-segregation of the AE1 R589H mutation with the disease phenotype in a family with dominant dRTA. Immunostaining of the kidney cortex from one affected member with superimposed chronic pyelonephritis revealed vH(+)-ATPase-positive intercalated cells in which AE1 was undetectable, and proximal tubular epithelial cells with apparently enhanced apical vH(+)-ATPase staining. CONCLUSIONS: The highly polymorphic dinucleotide repeat adjacent to the human AE1 gene may be useful for future studies of disease association and haplotype analysis. Intercalated cells persist in the end-stage kidney of a patient with familial autosomal dominant dRTA associated with the AE1 R589H mutation. The absence of detectable AE1 polypeptide in those intercalated cells supports the genetic prediction that the AE1 R589H mutation indeed causes dominant dRTA.     

妊娠肝内胆汁淤积症患者血清一氧化氮和内皮素的变化及意义

目的：探讨妊娠肝内胆汁淤积症（ICP）患者外周静脉血清、新生儿脐静脉血清中一氧化氮（NO）、内皮素（ET）、丙二醛（MDA）和超氧化物歧化酶（SOD）含量的变化及在ICP发病中的作用。方法：以ICP组28例为研究组，测定其外周静脉血清及新生儿脐静脉血清中的NO、ET、MDA和SOD，以年龄相近的24例正常孕妇作为对照组。结果：ICP患者的MDA和ET含量较正常晚期妊娠显著增高（P＜0．01），ICP患者的NO和SOD含量与对照组相比无显著性差异（P＞0．05）。母血清中NO、ET、MDA含量均较新生儿脐静脉血清中的含量高，差异有显著性（P＜0．01）。结论：妊娠期体内氧化和抗氧化失衡及ET水平的增高可能与ICP的发生、发展有关。