A pharmacokinetic comparison of the corn oil versus microemulsion gelcap formulation of cyclosporin used de novo after renal transplantation

The initial poor absorption of the corn oil-based, gel capsule oral formulation of cyclosporin (CyA) greatly limits its use for inception of immunosuppressive therapy. Insufficient drug concentrations during the early post-transplant period predispose to renal allograft rejection. The present study served to compare the time required to achieve therapeutic CyA concentrations after de novo administration of the corn oil-based gel capsule (CyA-GC; n = 11) versus the microemulsion (CyA-ME; n = 11) formulation of CyA. During the 1st month after renal transplantation, patients underwent serial pharmacokinetic profiling from which we obtained observed and dose-corrected values of several parameters. Although patients in neither the CyA-GC nor the CyA-ME group adequately absorbed the drug during days 0–2, from day 3 to 4 patients in the CyA-ME group showed significantly greater absorption than those in the CyA-GC group (P = 0.041). Patients in the CyA-ME group reached the 1st month target average concentration (C_av) values ( ≥ 550 ng/ml) earlier than those in the CyA-GC group and required significantly lower daily CyA doses (P = 0.018). We conclude that therapeutic CyA levels can be achieved more rapidly and with lower doses of the drug after de novo administration of CyA-ME than with CyA-GC. Received: 13 September 1996 Accepted: 7 January 1997     

Ultra-high-pressure liquid chromatography–solid-phase clean-up for determining aflatoxins in Egyptian food commodities

In this work, we determined the content of regulated aflatoxins (ATs) B1, B2, G1, and G2 in food commodities using solid-phase extraction (SPE) and ultra-high-pressure liquid chromatography with fluorescence detection without derivatization. We extracted ATs from the ground samples by mixing in NaCl and 80% (v/v) methanol. The sample was enriched and cleaned up by SPE technique using Bakerbond^® C18 cartridges. The extract that we obtained was immediately analyzed using isocratic elution with a mobile phase consisting of acetonitrile, methanol and deionized water in a ratio of 64:18:18. Method validation was carried out by determining these ATs in a quality control material consisting of almond T02445QC and with the add-found test. The results provided satisfactory recovery within the range of 89.6–103.3%. Repeatability and intermediate precisions were assessed as RSD (%) which were found in the range of 1.1–11.3% and 1.5–12.0%, respectively. The limit of detection (S/N = 3) was 0.03, 0.02, 0.04, and 0.02 μg kg⁻¹ for B1, B2, G1 and G2, respectively. Finally, the method was successfully applied to determine ATs in raw Egyptian food commodities, namely maize, popcorn, pistachio, corn, peanuts, chilli, wheat, green coffee and almond, and the corresponding RSD did not exceed 11%.     

响应面法优化玉米须中总黄酮的超声提取工艺

目的 研究玉米须中总黄酮的超声波提取工艺及其抗氧化活性.方法 以提取时间、料液比、乙醇体积分数为自变量,以总黄酮的提取率为响应值,经过3因素3水平的响应面Box-Behnken法确定玉米须中总黄酮的最优提取条件.结果 最佳提取工艺为:超声功率500W,超声提取时间为20min,料液比1∶20,乙醇体积分数30％.在此条件下,总黄酮的提取率为1.13％.并用FRAP法对其抗氧化性进行了测定,得到FRAP值为467.59μmol/L.结论 玉米须总黄酮是一种较好的天然自由基清除剂.     

Hypercoagulation following brain death cannot be reversed by the neutralization of systemic tissue factor

Background

Cerebral injury and brain death is associated with apparent hypercoagulation and poor organ outcome. This experimental study challenges the hypotheses that i) brain death causes hypercoagulation and microvascular thrombosis and that ii) neutralizing systemic tissue factor (TF) by in vitro addition of a TF inhibitor (recombinant active site-inhibited factor VIIa (ASIS)) can reverse the hypercoagulable profile.

Methods

Using a validated pig model of intracranial hemorrhage and brain death, 20 pigs were randomized to either control or brain death. The primary endpoints were coagulation parameters measured with whole blood thromboelastometry (ROTEM), thrombin generation and a porcine TF-sensitive plasma clotting time assay. In vitro spiking experiments with ASIS were performed in parallel with the latter two assessments. The kidneys were examined histologically for microvascular thromboses.

Results

Brain death induced hypercoagulation, as demonstrated with ROTEM, thrombin generation, and reduced TF-sensitive plasma clotting time. In vitro inhibition of TF with ASIS did not reverse the hypercoagulation. No microvascular thromboses were found in the kidneys.

Conclusion

Brain death causes hypercoagulation; however, inhibition of TF does not reverse the coagulopathy. Thus, TF release does not seem to be the primary cause of this hypercoagulation. Minor changes in the levels of protein C suggest that the protein C pathway may be linked to the observed coagulopathy.     

云南省昭通市氟中毒病区烘干玉米敞口存放及脱皮对玉米含氟量的影响

目的 了解玉米烘干后敞口存放、食用前再脱皮对玉米含氟量的影响,为燃煤型氟中毒的防治提供依据.方法 2006年10月,在云南省昭通市镇雄县燃煤污染型氟中毒病区,采集农户家中用当地煤火刚烘干的玉米34份,3个月后再次采集上述农户家中敞口保存的玉米并脱皮,采用高温燃烧水解-氟离子选择电极法测定玉米含氟量.结果 氟中毒区农户刚烘干玉米含氟量为(4.29±1.87)mg/kg,敞口存放3个月后含氟量升至(6.64±2.64)mg/kg,平均增加幅度高达54.74%;脱皮后玉米含氟量为(5.03±2.04)mg/kg,平均降低幅度约为24.25%.结论 在燃煤污染型氟中毒区,应采取密闭、防潮等措施合理存放烘干玉米,尽可能的食用脱皮后的玉米,可在一定程度上降低氟中毒病区居民的摄氟量,减轻燃煤型氟中毒的危害.     

玉米须总黄酮的提取及鉴别

目的为充分利用玉米须植物资源,避免资源的浪费,探讨玉米须总黄酮的提取及鉴别方法。方法采用纯物理的工艺流程过程和分光光度法从玉米须中提取黄酮类物质,对所提取的黄酮类物质进行验证。结果测得样品中总黄酮的含量C=6.45%,回收率为97.9%,其纯度和产率均较高。结论该方法采用全物理过程,无任何化学变化及污染,是提取玉米须黄酮类物质的有效途径。     

Impact of diets containing corn oil or olive/sunflower oil mixture on the human plasma and lipoprotein lipid metabolism

Summary Background The effects of monounsaturated fatty acids (MUFA) rich diets compared to those that are rich in polyunsaturated fatty acids (PUFA) as well as the effects of an intake of single oils compared to oil mixtures are controversially discussed and results are contradictory. Aim of this study To evaluate the effects of a plant oil-mixture (olive/sunflower oil; saturated/monounsaturated/polyunsaturated (S/M/P) = 14:69:17) high in oleic acid but also showing a moderate content of polyunsaturated fatty acids (PUFA) in comparison with a single, PUFA rich corn oil (S/M/P = 13:33:54) used in a normal, balanced diet on human plasma and lipoprotein metabolism. Methods The double-blind designed study comprised 28 healthy, non-smoking young men aged between 19 and 31 years. After two weeks of adjustment (mixed, balanced diet: 11.6 MJ average, average fat intake ∼105 g/d), the design included a two week test period in which a diet with 80 g corn oil/d vs a mixture of 68 g olive- and 12 g sunflower oil/d (total 80 g) as the main fat source was given, followed by a crossover after two weeks. Compliance and ingestion of diets were monitored by assessing the fatty acid pattern in LDL and by determination of α- and γ-tocopherol in plasma and LDL. Results Diets were well incorporated due to the significant changes in plasma- and LDL-tocopherol levels and the significant different average ratio of oleic acid to linoleic acid in LDL. The PUFA-rich corn oil diet was able to reduce low density lipoprotein (LDL) cholesterol from adjustment to T2 significantly (p < 0.01), which was also confirmed by a trend after cross over (p=0.15). Total cholesterol (only after cross over at T3), total triglycerides (TG) and very low density lipoprotein (VLDL)-TG were significantly lower at T2 after the corn oil diet than after the mixed oil diet. Total high density lipoproteins (HDL) and HDL cholesterol remained unchanged by both diets. Conclusions The results show that during the intervention of two weeks for each diet and the following cross over the corn oil diet had more influence on lipoprotein metabolism than the MUFA-rich diet. The hypocholesteremic effect of the PUFA-rich diet must also be connected with the high amount of unsaponifiable substances, mainly phytosterols in the corn oil. Received: 10 May 2001, Accepted: 17 September 2001     

Fumonisins and deoxynivalenol in corn-based food products in Portugal

A great diversity of crops is vulnerable to fungal attack and might be contaminated with mycotoxins. Currently it is estimated that 25% of the world's harvest production is contaminated to some level with these toxins. The presence of fumonisins and deoxynivalenol in corn-based foods, available in Portugal, was analyzed in order to produce some data that may be useful for hazard characterization. A total of 105 samples were screened, including, corn meal (41), sweet corn (49) and corn flakes (15). None of the 15 samples of corn flakes contained some detectable amount of fumonisins. However, fumonisin B1 (FB1) and fumonisin B2 (FB2) contamination was found in 100.0% and 70.7% of the corn meal samples, respectively. Sweet corn samples were positive in 73.4% for FB1, although no FB2 was detected. The highest levels of fumonisin were found in corn meal (maximum: 1300 microg FB1/kg and 450 microg FB2/kg). The presence of deoxynivalenol was not detected in any of the analyzed samples. Nevertheless these results indicate the need to establish, by corn products manufacturers, a continuous monitoring program to prevent and manage the occurrence of these contaminants.