纳米脂质体介导酪氨酸激酶受体3配体基因转染树突状细胞对结肠癌细胞凋亡的作用

目的 观察利用阳性纳米脂质体介导的基因治疗联合免疫治疗对结肠癌细胞的治疗作用.方法 应用基因克隆技术分别构建含有绿色荧光蛋白报告基因的重组质粒(pEGFP),并依据静电吸附原理制备携带基因的阳离子纳米脂质体,再将转染阳性的树突状细胞(DC)移植作用于结肠癌细胞.结果 成功构建含有绿色荧光蛋白报告基因的重组质粒,并得到酶切鉴定和序列测定证实.携带酪氨酸激酶受体3 配体(FL)基因的阳离子纳米脂质体成功转染DC,发现基因在细胞内得到很好表达,且随着培养时间的增加,蛋白表达量有所增加,72h时表达量最高.基因移植后发现对照组肿瘤体积增长最快,FL基因组肿瘤体积增长较慢；FL基因组肿瘤细胞凋亡率和死亡率明显高于对照组(P＜0.05)；而pEGFP组和对照组差异无统计学意义(P＞0.05).结论 阳离子纳米脂质体作为基因载体具有一定优越性.基因治疗联合免疫治疗在结肠癌治疗中具有重要意义.     

Non-clinical pharmacokinetics and pharmacodynamics of rVIII-SingleChain,a novel recombinant single-chain factor VIII

Introduction

rVIII-SingleChain (CSL627), a novel recombinant coagulation factor VIII (FVIII), is under investigation in a phase I/III clinical programme (AFFINITY) for the treatment of haemophilia A. Non-clinical studies were conducted to investigate the pharmacokinetic/pharmacodynamic profile of rVIII-SingleChain in comparison with full-length recombinant FVIII.

Materials and Methods

Binding affinity of rVIII-SingleChain for von Willebrand factor was investigated by surface plasmon resonance analysis. The pharmacokinetic profile of rVIII-SingleChain was compared with a marketed full-length recombinant FVIII concentrate (Advate^®) in haemophilia A mice, von Willebrand factor knock-out mice, Crl:CD (SD) rats, rabbits and cynomolgus monkeys. Systemic FVIII activity or antigen levels were recorded. Procoagulant activity was measured in an FeCl₃-induced arterial occlusion model and by recording thrombin generation activity (ex vivo) after administration of 200–250 IU/kg rVIII-SingleChain or full-length FVIII to haemophilia A mice.

Results

rVIII-SingleChain displayed a high affinity for von Willebrand factor (K_D = 44 pM vs. 139 pM for full-length recombinant FVIII). In all animal species tested, rVIII-SingleChain had more favourable pharmacokinetic properties than full-length recombinant FVIII: clearance was decreased and area under the curve and terminal half-life were enhanced vs. full-length recombinant FVIII, while in vivo recovery and volume of distribution were equivalent. rVIII-SingleChain showed a prolonged thrombin generation potential and prolonged procoagulant activity vs. full-length recombinant FVIII in an FeCl₃-induced arterial occlusion model.

Conclusions

rVIII-SingleChain had a higher affinity for von Willebrand factor than full-length recombinant FVIII and displayed favourable pharmacokinetic/pharmacodynamic properties in non-clinical models.     

利用噬菌体库筛选IL-6拮抗剂及功能研究

目的 以人sIL-6R为靶分子，利用噬菌体随机15肽库筛选其亲和短肽，结合计算机模拟分析，获得具有抑制IL-6／IL-6R结合作用的短肽序列，作为IL-6拮抗剂。方法 通过亲和筛选，获得一组sIL-6R特异亲和序列。测定序列，结合计算机模拟，选取具有潜在拮抗功能的2条肽(命名为pTl、pT2)。合成短肽，进行ELISA竞争抑制实验和细胞增殖抑制实验。结果 pTl、pT2均可抑制IL-6，sIL-6R的结合。pTl、pT2可抑制XG-7细胞的增殖，并且这种抑制作用随着合成肽浓度的增高而增强，pTl、pT2不影响。7TD1细胞的增殖。结论 利用亲和筛选并结合计算机模拟从随机15肽库中获得可抑制IL-6／sIL-6R结合的短肽，并可抑制IL-6依赖细胞XG-7的增殖。     

A new flow cytometric method for simultaneous measurement of residual platelets and RBCs in plasma: validation and application for QC

BACKGROUND: Guidelines for the preparation of FFP in Austria and Germany require the quantification of residual RBCs in plasma. However, currently there is no validated method for enumeration of RBC counts as low as 1 x 10(9) per L. STUDY DESIGN AND METHODS: A new flow cytometric method was developed for QC, to simultaneously determine if fresh unfrozen plasma contains residual platelets and RBCs. This method uses test tubes (TruCount, Becton Dickinson Immunocytometry Systems) that contain a known number of brightly fluorescent polystyrene beads. Plasma is pipetted into these tubes and mixed with FITC-labeled anti-CD41 and PE-conjugated anti-glycophorin A MoAbs. Acquisition can be performed on a flow cytometer after an incubation period of 15 minutes. RESULTS: Individual standard curves for platelet counts revealed excellent correlation coefficients (r>0.998). Platelet counts were validated against simultaneous measurements by using a cell counter and a hemocytometer. While the flow cytometric method slightly overestimated platelet counts of >40 x 10(9) per L by 10 percent, its precision in the critical range was very good-that is, a deviation of platelets < or = 1 x 10(9) per L from target values, which was even better than microscopic enumeration. The limit of sensitivity was <0.5 x 10(9) per L of platelets. RBC counts were also validated against simultaneous measurements made with a second cell counter. Standard curves for RBC counts also revealed excellent correlation coefficients (r>0.997). The limit of sensitivity was <0.25 x 10(9) RBCs per L. Platelet counts in plasma obtained by plateletpheresis or plasmapheresis ranged from 3 to 60 x 10(9) per L. About 25 percent of all plasma samples had platelet counts greater than the allowed upper limit of 25 x 10(9) per L, while all plasma samples contained fewer RBCs than the upper limit of 6 x 10(9) per L. CONCLUSION: This newly developed method provides a simple, quick, precise, and easily reproducible tool for simultaneous measurement of residual platelets and RBCs in fresh plasma.     

Automated radioimmunoassay of nicotine.

We have developed an automated nonequilibrium procedure for the radioimmunoassay of nicotine. The use of a unique iodinated nicotine derivative in this procedure gave a sensitivity of 10 micrograms/l for nicotine with a between-run precision of 7.4% and within-run precision of 6.0%. Nicotine levels of 60 to 67 micrograms/ml were found in subjects 15 min after smoking one standard cigarette. The technique herein reported is a very rapid, and sensitive radioimmunoassay for nicotine and facilitates the determination of nicotine in smoking subjects during the actual process of smoking.     

Successful parathyroidectomy guided by intraoperative parathyroid hormone monitoring for primary hyperparathyroidism is preserved in mild and moderate renal insufficiency

Background

The effect of altered parathyroid hormone metabolism in renal insufficiency on intraoperative parathyroid hormone monitoring during parathyroidectomy is not well known. This study evaluates operative outcomes in patients undergoing parathyroidectomy guided by intraoperative parathyroid hormone monitoring for primary hyperparathyroidism with mild and moderate renal insufficiency.

Allograft Portacaval Shunt in Small-for-Size Liver in Deceased Donor Liver Transplant

Portal hyperperfusion is detrimental to small-for-size livers (SFSLs) in liver transplantation. Surgical techniques modulating portal inflow provide the most effective approach to protect the SFSL. In this report, we describe a technique creating an allograft portacaval shunt that effectively attenuates portal inflow without a requirement of extensive surgical dissection in the recipient during the transplantation.