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排序方式: 共有492条查询结果,搜索用时 296 毫秒
1.
自“缬沙坦事件”之后,N-亚硝胺类基因毒性杂质引起了业界的广泛关注。本文概述了药物中N-亚硝胺类基因毒性杂质和相关检测方法的研究进展,以及近20年来国内外有关药物中基因毒性杂质监管指南的完善历程。N-亚硝胺类基因毒性杂质作为一类高反应活性的基因毒性杂质,主要来源于药物合成过程中发生的副反应,以及药物在储存或者运输过程中发生的氧化或还原等反应。所有的动物实验表明,N-亚硝胺类具有很强的致癌性。在理论上,所有药物都存在N-亚硝胺类杂质或被N-亚硝胺类杂质污染的风险,由于该类化合物在药物中常以痕量形式存在,在分析检测过程中药物基质干扰大,因此建立便捷、高效的分析方法是非常有必要的。 相似文献
2.
目的:建立顶空气相色谱-质谱法测定布南色林原料药中甲磺酸甲酯、甲磺酸乙酯和甲磺酸异丙酯3种遗传毒性杂质含量的方法。方法:采用顶空气相色谱-质谱法,以甲磺酸丁酯为内标,按内标标准曲线法进行甲磺酸甲酯、甲磺酸乙酯和甲磺酸异丙酯的含量测定。色谱条件:DB-WAX毛细管色谱柱(30 m×0.25 mm×0.25 μm);程序升温,初始柱温为40℃,维持3 min,升温速率为30℃·min-1,终止温度150℃,保持2 min;进样口温度为110℃;载气(He)流速为0.6 mL·min-1;进样量为1 mL;进样方式为分流进样,分流比为20:1。质谱条件:电子轰击离子源(EI),扫描方式为选择性离子检测;离子源温度为200℃;接口温度为150℃;电子能量为70 eV;溶剂延迟1 min。结果:3种杂质成分之间的分离度均大于2.0;甲磺酸甲酯、甲磺酸乙酯、甲磺酸异丙酯检测质量浓度线性范围均为0.025~3.0 μg·mL-1(r ≥ 0.998 5);精密度、稳定性、重复性试验的RSD<5%;加样回收率分别为93.40%~101.40%(RSD为3.2%,n=9)、92.80%~99.70%(RSD为2.5%,n=9)和96.30%~100.75%(RSD为1.6%,n=9)。结论:该方法简便、准确、灵敏、迅速,可用于布南色林原料药中3种遗传毒性杂质的测定。 相似文献
3.
S. Vemuri 《Chemical biology & drug design》2005,65(4):433-439
Abstract: Precise determination of the peptide content in drug substance samples depends highly upon the particular peptide compound and methodology used. Four independent methods were evaluated and compared to determine which would produce the best experimental precision for analysis of thymalfasin (thymosin α‐1). Four different methods were evaluated including elemental analysis (CHN), quantitative amino acid analysis (AAA), high‐performance liquid chromatography (HPLC), and Kjeldahl. This study demonstrates that the AAA method is highly variable in one laboratory while quite precise in another laboratory. Similarly, HPLC results depended on the laboratory conducting the study with more precise values obtained under cGMP. On the contrary, the CHN method yielded highly precise [i.e. <2% coefficient of variation (CV)] values. As precise knowledge of protein content is fundamental for the compounding of final pharmaceutical product of a specific potency, the CHN analysis is recommended for peptide content determination of the drug substance thymalfasin. 相似文献
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5.
P DESREUMAUX A LEVY J P VAERMAN M CAPRON A CORTOT J F COLOMBEL 《Clinical and experimental immunology》1996,104(2):293-296
The effects of nutrients on the mucosal immune system are poorly understood. The aim of this work was to study the cellular mucosal immune response to intrajejunal perfusion of an elemental diet (ED) or a control (C) electrolyte solution by measuring jejunal secretion of soluble CD4 (sCD4) and sCD8. sCD4 and sCD8 are markers of helper/inducer and suppressor/cytotoxic regulatory functions of T cells, respectively. A four lumen tube with a proximal occluding balloon at the angle of Treitz was used for jejunal perfusion in seven healthy volunteers (mean age 23 years). The length of the test segment was 40 cm. The jejunum was successively perfused with C for 80 min and then with ED containing 21.3g/l of free amino acids and 104.2g/l of oligosaccharides for 100 min. Jejunal fluid and serum concentrations of sCD4 and sCD8 were measured and their jejunal outputs calculated. When compared with C perfusion, jejunal perfusion with the ED resulted in a significant increase of sCD8 but not sCD4 jejunal secretion rates. sCD8 jejunal values increased early after ED perfusion and stayed at roughly the same level during the perfusion. Serum concentrations of sCD4 and sCD8 were not modified during ED perfusion. These data support the hypothesis that ED suppresses the immunologic tone of the gut, which could explain its beneficial effect in the management of intestinal inflammatory disease. 相似文献
6.
Farquhar J Finlay G Ford PA Martin-Smith M 《Journal of pharmaceutical and biomedical analysis》1985,3(3):279-285
A stability-indicating assay is described for the determination of N-acetylcysteine in aqueous pharmaceutical formulations. The sample is diluted to an appropriate concentration with dilute aqueous orthophosphoric acid. An aliquot of the solution, containing added l-tyrosine as an internal standard, is chromatographed using a 10-mum C(18) stationary phase with dilute orthophosphoric acid (pH 2.0) containing 0.5% w/v of sodium perchlorate as the mobile phase. The assay, which has a relative standard deviation of about 0.8%, can also be used as a test for related impurities in N-acetylcysteine. It is also suitable for determining the N-acetylcysteine content of the drug substance. 相似文献
7.
目的:生产注射葡萄糖酸钙。方法:以口服葡萄酸钙为原料,通过提高其澄明度和降低其杂质含量使其达到注射葡萄糖酸钙的质量要求。结论:本工艺方法具有投入设备少、副反应少、产品质量好等特点。 相似文献
8.
9.
《Inhalation toxicology》2013,25(14):906-917
Context: Diesel exhaust particles (DEP) are an important contributor to suspended particulate matter (PM) in urban areas. While epidemiological evidence exists for a sex-influenced dose-response relationship between acute PM exposure and respiratory health, similar data are lacking for DEP. Further, experimental evidence showing deleterious effects on respiratory health due to acute DEP exposure is sparse.Objective: To establish and characterize a mouse model of acute DEP exposure, comparing male and female mice and assessing the kinetics of the elemental carbon content of alveolar macrophages (AMs) to relate our model to human exposure.Materials and Methods: Adult BALB/c mice were intranasally inoculated with 0 (control), 10, 30 or 100 µg DEP in saline. Bronchoalveolar lavage cellular inflammation and cytokine levels were assessed 3, 6, 12, 24, 48 and 168 hours post exposure. Elemental carbon uptake by AMs was additionally assessed at 336 and 672 hours post DEP exposure. Thoracic gas volume and lung mechanics were measured 6 and 24 hours post exposure. Results: DEP resulted in dose-dependent cellular inflammation and cytokine production in both sexes. Males and females responded differently with females having more severe and prolonged neutrophilia, monocyte chemoattractant protein-1 and developing greater abnormalities in lung function. The sexual dimorphism in response was not related to the capacity of AMs to phagocytise DEP.Conclusions: Our mouse model of acute diesel exhaust particle exposure shows a dose dependency and sexual dimorphism in response. Quantification of elemental carbon in AMs allows for comparison of the results of our study with human studies. 相似文献
10.
原料药中基因毒性杂质控制的研究进展 总被引:5,自引:5,他引:0
目的介绍原料药(active pharmaceutical ingredient,API)中基因毒性杂质控制的法规要求、评估方法和控制方法。方法通过学习欧美法规发展历史,理解国际高端市场对基因毒性杂质控制的监管期望,提出原料药中基因毒性杂质风险评估方法。结果与结论企业基于半定量评估,结合清除研究数据,建立科学的控制策略,使实际工艺中所有可能涉及的基因毒性杂质风险得到明确鉴别和控制,是达到监管期望的有效途径。 相似文献