青蒿素和青蒿琥酯对人乳腺癌MCF-7细胞的体外抑制作用比较研究

目的 对比研究青蒿素及其衍生物青蒿琥酯对人乳腺癌MCF—7细胞增殖的影响并探讨其作用机制。方法 采用体外培养的人乳腺癌MCF—7细胞株，利用SRB法测定青蒿素和青蒿琥酯对MCF—7细胞增殖的影响，FCM法测定细胞周期的变化，亚Gl期含量测定和DAN荧光染色法观察细胞凋亡。结果 10μmol/L青蒿素和lμmol/L青蒿琥酯能明显改变MCF—7细胞的细胞周期，使S期细胞显著减少，G0 Gl期细胞明显增加。青蒿素对MCF—7细胞增殖仅有微弱抑制作用，但其衍生物青蒿琥iB却有显著的抑制作用，IC50为0．3lμmol/L。同样，lμmol/L青蒿琥酷引起MCF—7细胞的凋亡和直接的细胞毒作用明显强于10μmol/L青蒿素的作用。结论 体外研究表明，对肿瘤细胞增殖的抑制青蒿琥酯比青蒿素作用强。     

Association of a genetic polymorphism in human apolipoprotein B-100 with intermediate density lipoprotein concentrations

Immunochemical techniques have been used to identify five antigenic (Ag) sites on apolipoprotein B-100 (apoB), the major protein constituent of very low density (VLDL), intermediate density (IDL), and low density lipoproteins (LDL). Each Ag site results from allelic variation at a specific locus of the apoB gene. In the present study, we assessed whether variations in the five Ag loci were associated with concentrations of plasma lipids or lipoprotein fractions measured by analytical ultracentrifugation in a group of 44 healthy men. Pair-wise analyses of the Ag markers revealed that Ag(a1/d), in association with either Ag(x/y) or Ag(t/z), is significantly related to plasma IDL-mass concentrations. In this cohort we detected no significant associations of the Ag alleles (singly or in combination) with plasma total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, or mass of total VLDL or LDL. These results suggest that genetic variations in the apoB molecule may predispose to variations in concentrations of IDL that could have consequences for atherosclerotic risk.     

No regression of renal AL amyloid in monoclonal gammopathy after successful autologous blood stem cell transplantation and significant clinical improvement.

BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress.     

Morphological analysis of renal cell culture models of calcium phosphate stone formation

Cell culture models of calcium phosphate renal stone formation were established using the MDCK cell line. Renal microliths were detected within pseudocysts in three-dimensional soft agar cultures, and were also observed in the basal region of cells lining the cell sheet, and immediately beneath domes or blisters in monolayers and collagen gel cultures. Light and scanning electron microscopy indicated that these microliths had a similar lamellated and spherical appearance to those in humans. These microliths were first detected microscopically after 21 days of culture, and were found to be composed of calcium phosphate by X-ray and microinfrared spectroscopic analyses. These culture models may provide a powerful new tool to study the pathogenesis of renal stone diseases and/or calcium phosphate stone formation in humans and animals.     

血液胆碱酯酶活力测定方法的进一步研究Ⅰ．红细胞／全血胆碱酯酶活力比例及红细胞计数校正酶活力值的研究

应用硫代乙酰胆碱－联硫代双硝基苯甲酸（ＡＳＣｈ－ＤＴＮＢ）比色测定法，测定了４０名健康者及５名贫血者血样的全血胆碱酯酶（ｂｌ－ＣｈＥ）活力值、红细胞胆碱酯酶（ｅ－ＣｈＥ）活力值及血浆胆碱酯酶（ｐ－ＣｈＥ）活力值，探讨它们之间的比例关系并用红细胞计数值（ＲＢＣ）校正酶活力。结果表明：ｅ－ＣｈＥ与ｂ１－ＣｈＥ之间关系密切（ｒ＝０．９４８，Ｐ＜０．００１），ｅ－ＣｈＥ稳定地占ｂｌ－ＣｈＥ的８４．９７％，在质和量两方面验证了以ｂｌ－ＣｈＥ值表示ｅ－ＣｈＥ值的可靠性和可信程度，血液胆碱酯酶（ｂ１ＣｈＥ）活力主要取决于ｅ－ＣｈＥ活力，ＲＢＣ值的离散对ｅ－ＣｈＥ值有极大影响，故用ＲＢＣ值校正ｅ－ＣｈＥ活力，这样可缩小人群测定值的变异度，得到较难确的群体均值；消除男女之间测定值的差异，建立更合理和通用的临界参比值，极大地方便了使用，使血液胆碱酯酶（ＣＨＥ）活力测定法在防治有机磷农药中毒中的应用，更为敏感和特异。     

A rapid solid-phase extraction and HPLC/DAD procedure for the simultaneous determination and quantification of different benzodiazepines in serum,blood and post-mortem blood

Summary A rapid and quantitative method for the determination of benzodiazepines using high-performance liquid chromatography (HPLC) with diode-array detection (DAD) is reported. The drugs were extracted from serum, blood or post-mortem blood using C₁₈ extraction columns. Brotizolam was used as internal standard. Experiments with spiked serum/blood samples resulted in recoveries between 75% and 94% for all investigated benzodiazepines. Excellent linearity was obtained over the concentration range 5–1500 ng benzodiazepine/ml. The limit of detection was approximately 2 ng/ml. The detection of low therapeutic serum levels of highly potent benzodiazepines is also possible.      

Gd-DTPA-cascade-polymer: Potential blood pool contrast agent for MR imaging

Gadolinium-DTPA (diethylenetriaminepentaacetic acid)-cascade-polymer, a potential new blood pool contrast agent for magnetic resonance (MR) imaging, was compared with a known blood pool agent, Gd-DTPA-polylysine, in an animal model. The relative signal intensities of liver, renal cortex, pancreas, and trunk muscle were assessed in 12 pigs between 4 seconds and 120 minutes after injection of a 20 μmol/kg dose of each contrast agent, by using a FLASH (fast low-angle shot) sequence. Except for muscle, all tissues showed visible enhancement after injection of either contrast agent. After injection of Gd-DTPA-polymer, enhancement patterns in the liver, renal cortex, and pancreas were similar to those seen after injection of Gd-DTPA-polylysine. No statistically significant differences in enhancement between the two contrast agents were found at any time point. The authors conclude that the contrast kinetics of Gd-DTPA-cascade-polymer are similar to those of Gd-DTPA-polylysine and that this agent may also be used as a blood pool contrast agent for MR imaging.     

Expression of the cell surface antigen detected by the monoclonal antibody A7 in pancreatic carcinoma cell lines

In a previous study, we used a murine monoclonal antibody, A7, against human colon carcinoma as a drug-carrier to treat colorectal cancer.¹ In the present study, we found that MAb A7 also reacted immunohistochemically with 73% of human pancreatic carcinoma cell lines, with the A7 antigen mainly being detected on the cell surface. However, the A7 antigen was found in only 9% of the spent media of these human pancreatic carcinoma cell lines by ELISA. On the other hand, the positive incidence of CA19-9, POA, ferritin, CEA, DU-PAN-2 and SLX in those spent media was 100%, 64%, 64%, 55%, 55% and 36%, respectively. These results suggest that the A7 antigen may only rarely be shed into the sera of pancreatic cancer patients, in which case MAb A7 could be a suitable drug-carrier in targeting chemotherapy for pancreatic cancer patients.