Adverse drug reactions: physicians' opinions versus a causality assessment method

Since spontaneous reporting of adverse drug reactions depends on the physician's opinion of the relationship between the drug and the adverse event, we compared physicians' opinions with the scores obtained by the causality assessment method used in France. During a 2 month period, all physicians who reported adverse drug reactions (ADRs) to our pharmacovigilance centre expressed their opinions on the causal link by means of visual analogue scales. ADR reports were then assessed with the French causality assessment method by a clinical pharmacologist who was blind to physicians' opinions.The assessment by both physicians and the standardized method was performed for 75 ADR cases involving 120 drugs. Physicians used a wide range of assessments, with a preponderance of extreme scores, resulting in a U-shaped distribution, while the standardized method gave generally low scores. Scores given by physicians were very high (causality considered very likely or likely) in 60% of cases and very low (causality considered unlikely or dubious/possible) in 32% of cases. Scores obtained using the causality assessment method were low (causality dubious/possible) in 89% of cases and causality considered likely in only 11 cases, essentially in cases with positive rechallenge. Complete agreement occurred in only 6% of cases. Adding complete agreement and minor discrepancies raised the percentage to 49%.     

Adverse reactions to non-ionic contrast media with special regard to high-risk patients

Non-ionic contrast media (CM) are proven to be significantly safer than the high osmolar ionic contrast media (HOCM). Nevertheless deaths are reported after administration of non-ionic agents. The aim of the study was to investigate the rate of adverse reactions to non-ionic CM with special regard to high-risk patients and the effects of premedication with H1-and H2-receptor antagonists.In a prospective study conducted over about 2 years 12 995 examinations with intravenous or intra-arterial non-ionic CM were evaluated. Premedication with H1-and H2-antagonists was used in 1276 high-risk patients with known adverse reaction to CM, history of allergy or severe cardiac or pulmonary disease. 229 patients received no premedication inspite of known risk factors. In total, there were 143 (1.10%) adverse reactions (mild in 0.58%, moderate in 0.41% and severe in 0.05%). In high-risk patients there were adverse reactions in 4.37% without and in 1.57% with premedication. There were no severe adverse reactions in the high-risk patients after premedication. The age of the patient, CM dosage and CM concentration were not shown to be risk factors in the present study. In conclusion, the additional premedication with H1- and H2-antagonists could be an effective agent to reduce the risk of mild and moderate adverse reactions and to avoid severe adverse reactions in high-risk patients. Correspondence to: U. Fink     

海南文昌汉族人群中两种葡萄糖-6-磷酸脱氢酶基因突变的研究

目的:分析海南文昌人群中葡萄糖-6-磷酸脱氢酶基因1376G→T、95A→G突变。方法:应用硝基四氮唑蓝定量法进行G6PD缺乏症的筛查,用等位基因特异PCR检测1376G→T、95A→G突变。结果:在358位海南文昌汉族人中,发现G6PD缺乏症患者20例,其中9例患者有1376G→T突变,3例患者有95A→G突变。结论:1376G→T、95A→G突变是文昌人群中常见的突变。     

No evidence for an altered mRNA expression or protein level of haematopoietic cell phosphatase in CD34+ bone marrow progenitor cells or mature peripheral blood cells in polycythaemia vera

Abstract: Polycythaemia vera (PV) is a myeloproliferative disorder characterized by haematopoietic progenitor cells being hypersensitive to cytokines such as erythropoietin, interleukin-3, stem cell factor and insulin-like growth factor 1, which results in an increased production of mature blood cells. The pathogenetic cellular mechanism(s) behind this hypersensitivity to cytokines is unknown, but the number of cytokine receptors and the interaction between ligand and receptor are normal in PV. Interest has therefore focused on post-receptor mechanism(s). Haematopoietic cell phosphatase (HCP) is an intracellular tyrosine phosphatase that has been demonstrated to regulate proliferative signals negatively induced by the cytokines mentioned above. Moreover, motheaten mice that genetically lack HCP have an increased amount of erythroid progenitors that are hypersensitive to Epo, and patients with familial polycythaemia have been shown to exhibit a mutation of the Epo receptor gene that includes the docking site for HCP. We therefore studied mRNA expression of HCP in pure populations of CD34⁺ cells, granulocytes, platelets and lymphocytes from patients with PV, chronic myeloid leukaemia (CML) or essential thrombocythemia (ET), as well as healthy controls. Using a polymerase chain reaction analysis employing specific primers for HCP, we failed to detect any abnormalities of HCP expression in PV in any of the cell populations that were examined. Moreover, HCP mRNA expression was similar in ET and CML compared to controls. Finally, Western blot analysis revealed a normal HCP protein content in PV granulocytes and platelets. We therefore conclude that neither an impaired expression of the HCP gene nor a defect in HCP protein synthesis is present in PV, and does not seem to play a role in the aetiology of this disorder.     

磷脂酶C与生殖

磷脂酶C(PLC)是磷脂酰肌醇信号转导途径中一个关键酶。目前确认的哺乳类PLC共有PLC β、PLC γ、PLC δ、PLC ε和最近新发现的PLC ζ 5种亚型 ,12种同工酶。不同亚型的结构、调控和组织分布各有差异。PLC在调控信号转导通路中的特性使其在顶体反应、卵子激活中发挥了巨大的作用。本文综述了PLC家族 5种亚型的结构、调控机制及PLC在男性生殖领域的相关内容 ,包括PLC引起卵子发生Ca2 + 振荡、激活卵子、促进胚胎发育等 ,并进一步探讨了PLC在临床上可能的应用前景。     

临床输液反应的分析与预防

目的对临床发生的输液反应进行分析,找出发生的原因,探讨预防措施。方法:对30例输液反应资料进行分析。结果:以热原反应最为多见,占76.67%,而过敏反应,占16.67%,局部反应,占6.67%。结论:严格执行消毒制度,遵守无菌操作规程,把好药品和输液器具质量关,合理用药,注意配伍等是减少临床输液反应的关键。     

脊麻药复合微量芬太尼对防治牵拉反应的探讨

目的 探讨脊麻药中复合微量芬太尼对牵拉反应的防治效果。方法 选择美国麻醉医师协会（american society of anesthesiologists，AsA）Ⅰ-Ⅱ级、足月、初产及单胎而需行剖宫产术的病人60例，随机分成2组，每组30例。2组病人的年龄、性剐、体重、局麻药用量、麻醉方法均无显著性差异，均选用腰硬联合麻醉（combined spinal—epidural anesthesia，CSEA）。A组：等比重0．5％罗哌卡因9-11mg＋芬太尼10μg。B组：等比重0．5％罗哌卡因9-11mg。观察术中牵拉反应和生命体征并记录，进行统计学处理。结果 2组间麻醉前、后相对应的MAP（平均动脉压）、HR（心率）、RR（呼吸频率）和SpO2（血氧饱和度）变化均无显著性差异（JP〉0．05），2组间新生儿Apgar评分均无显著性差异（P〉0．05），比较2组术中的牵拉反应，A组明显优于B组，有显著性差异（P〈0．05）结论 脊麻药中加入微量芬太尼对牵拉反应有良好的防治效果。     

血管紧张素对增生性瘢痕成纤维细胞纤维连接蛋白合成的影响

目的：探讨血管紧张素Ⅱ（AngⅡ）及其Ⅰ型、Ⅱ型受体阻断剂和钙调神经磷酸激酶（CaN）的阻滞利环胞素A（CsA）对增生性瘢痕来源的成纤维细胞纤维连接蛋白mRNA和蛋白表达的作用。方法：体外分离培养增生性瘢痕成纤维细胞，分别将一定浓度的AngⅡ（10^-9～10^-5mmol／L），和AngⅡ10^-6mmol／L加上不同阻滞剂losartan、PD123319、环胞素A（浓度均为10^-5mmol／L）加入细胞培养液中刺激48h，分别采用逆转录聚合酶链反应（RT—PCR）及Westernblot印迹方法检测增生性瘢痕成纤维细胞纤维连接蛋白（FN）的mRNA及蛋白表达。结果：体外成功地培养增生性瘢痕成纤维细胞。经AngⅡ刺激48h后，FN mRNA和蛋白表达量明显增高，增高程度与AngⅡ浓度呈正比；加入losaartan和环胞素A后，FN原mRNA和蛋白表达量较单用AngⅡ组下降，而加入PD123319后，FNmRNA和蛋白表达量较单用AngⅡ组无明显改变。结论：AngⅡ可促增生性瘢痕成纤维细胞的FN合成，可能在增生性瘢痕的发展过程中起重要作用，该作用主要通过AngⅡ的Ⅰ型受体介导完成，该作用可能与CaN信号通路有关。