Endotoxin transfer through dialysis membranes: small- versus large-pore membranes.

In this in-vivo study, dialysate and serum endotoxin was evaluated before and after haemodialysis with small-pore (PS400) and large-pore (PS600) polysulphone dialysers, and before and after haemodiafiltration with the PS600 filter. The source of the endotoxin was the presence in dialysate of Pseudomonads at a concentration of 10(3)-10(4) CFU/ml. Endotoxin was measured by a modified chromogenic limulus amoebocyte lysate (LAL) assay. In spite of dialysate endotoxin concentrations greater than 100 pg/ml, no changes in pre- versus posttreatment LAL reactivity were observed in PS400 dialysis and PS600 haemodiafiltration. In contrast, PS600 haemodialysis was related to an increase in serum LAL reactivity from 1.3 +/- 1.5 to 3.8 +/- 2.0 pg/ml (n = 15, P less than 0.01), and five patients (33.3%) showed a post-dialysis value in excess of 5 pg/ml. Our data are consistent with the absence of in-vivo endotoxin transfer during haemodialysis with small-pore dialyser membranes, and during haemodiafiltration with membranes with larger pores. An increase in LAL reactivity during haemodialysis with membranes with larger pores is, however, present, presumably due to the occurrence of backdiffusion/filtration with that specific strategy.     

体外人全血热原检测方法的研究

 目的 对体外人全血热原检测方法进行优化。方法 采用酶联免疫吸附实验(ELISA)法测定血液中释放的内源性热原。结果 TNF-α,IL-1β,IL-6这3种细胞因子均可作为测定指标;血液和供试品的反应时间确定为6 h;血液稀释倍数确定为1→2稀释;血液的保存温度确定为4℃;血液的保存时间确定为4 h;加样体积比确定为血液-供试液=4:1。结论 本研究结果为体外人全血热原检测法的标准化打下初步基础。     

血液透析患者出现热原反应原因调查

为探寻血液透析患者出现热原反应的原因,进行了微生物污染与消毒剂浓度调查。结果,消毒透析器所用过氧乙酸浓度低至０．０５％～０．１６％,贮罐中自来水、反渗水及透析器入口处透析液的细菌总数分别高达 １１ ２００ｃｆｕ／ｍｌ、 １５８０ｃｆｕ／ｍｌ与 １２５０ｃｆｕ／ｍｌ,透析液、反渗水细菌内毒素阳性率均为 １００％（ ２０／ ２０）。经确保过氧乙酸浓度≥０．３％,缩短消毒周期,改善液体过滤除菌设备,液体微生物检测均达标,未再出现热原反应。     

精氨酸加压素对内毒素诱生内生致热原生成及致热性的影响

本文观察了精氨酸加压素（ａｒｇｉｎｉｎｅｖａｓｏｐｒｅｓｓｉｎ，ＡＶＰ）对体外培育的家兔血细胞生成内生致热原（ｅｎｄｏｇｅｎｏｕｓｐｙｒｏｇｅｎ，ＥＰ）及体内ＥＰ性发热的抑制作用。实验结果如下：１．给家兔分别静脉注射不同培养条件下获得的ＥＰ或ＥＰ＿ａ。ＥＰ＿ａ是在培养过程中加入ＡＶＰ而获得的。结果显示，ＥＰ＿ａ组发热效应明显低于ＥＰ组（Ｐ＞０．０５）。２．静脉注射ＥＰ＋ＡＶＰ组的发热效应比ＥＰ组明显降低（Ｐ＜０．００１）。实验结果表明，ＡＶＰ退热作用的机理之一可能是由于ＡＶＰ抑制了内毒素（ｅｎｄｏｔｏｘｉｎ，ＥＴ）诱生ＥＰ的生成和对抗了ＥＰ的致热活性所致。     

细菌内毒素检测法与家兔法同步检测磷酸川芎嗪注射液热原的比较

目的:考察细菌内毒素检查法对磷酸川芎嗪注射液进行检查的可行性。方法:用细菌内毒素检查法对磷酸川芎嗪注射液进行干扰实验;用细菌内毒素检测法对家兔热原试验不同结果的磷酸川芎嗪注射液进行比较试验。结果:供试品对鲎试剂与内毒素的反应无干扰作用。家兔热原检查法阴性结果与细菌内毒素检查法结果相吻合,并且热原检查阳性结果也吻合。结论:用细菌内毒素检查法检测磷酸川芎嗪注射液热原是可行的。     

二次灭菌对热原不合格输液质量的影响

目的考察二次灭菌对三种大输液热原等指标的影响情况。方法利用不同条件对三种大输液进行二次灭菌,比较了灭菌前后输液中内毒素的最大稀释倍数、pH、含量和5-HMF的变化。结果9g.L-1氯化钠注射液、100g.L-1葡萄糖注射液和50g.L-1葡萄糖注射液可分别选用四、三和三种二次灭菌条件。结论输液热原不合格时,可根据最大稀释倍数选用适宜的二次灭菌条件,进行第二次灭菌以减少损失。     

Naloxone does not antagonize leukocytic pyrogen

In a crossover experiment, cats were given third cerebral ventricular injections of 500 microgram naloxone hydrochloride or saline vehicle followed in 15 min by i.v. injections of saline solution or leukocytic pyrogen. The pyrogen produced comparable fevers after both saline and naloxone pretreatment. Intravenous administration of naloxone hydrochloride (5 mg/kg) likewise did not prevent febrile responses to leukocytic pyrogen. These results indicate that endogenous opioid peptides are not likely central mediators of pyrogen-induced fevers.     

Fever during anaesthesia

Fever occurs when pyrogenic stimulation activates thermal control centres. Fever is common during the perioperative period, but rare during anaesthesia. Although only a limited number of studies are available to explain how anaesthesia affects fever, general anaesthesia seems to inhibit fever by decreasing the thermoregulatory-response thresholds to cold. Opioids also inhibit fever; however, the effect is slightly less than that of general anaesthesia. In contrast, epidural anaesthesia does not affect fever. This suggests that hyperthermia, which is often associated with epidural infusions during labour or in the post-operative period, may be a true fever caused by inflammatory activation. Accordingly, this fever might be diminished in patients who receive opioids for pain treatment. Post-operative fever is a normal thermoregulatory response usually of non-infectious aetiology. Fever may be important in the host defence mechanisms and should not be routinely treated lest the associated risks exceed the benefits.     

超滤法去除氨基酸原料中热原的工艺条件研究

采用超滤方法去除谷氨酸、盐酸赖氨酸和丙氨酸产品中的热原,研究了料液浓度、操作压力、料液流速和温度对产量的影响,及膜的清洗方法。当料液浓度为１００～１５０ ｇ／Ｌ,温度为４０～５０℃时,ＨＷ４－２×４ 型卷式超滤器处理氨基酸产品的产量约为２０ Ｌ·ｍ － ２·ｈ－ １,经处理后产品的热原指标均合格。     

硫酸小诺霉素注射液细菌内毒素检查法

本文对采用细菌内毒素检查法检测硫酸小诺霉素热原的可行性进行了研究。结果表明硫酸小诺霉素注射液稀释至５００单位／ｍｌ时,对细菌内毒素检查无干扰作用。