红细胞游离原卟啉在非缺铁婴幼儿中的分布特征及正常值探讨

本文分析了336名非缺铁婴幼儿红细胞游离原卟啉(Free Erythro-cyte Protoporphyrin,FEP)水平。结果表明,336名婴幼儿FEP呈正态分布,正常值为360μg/L全血,界限值500μg/L;FEP水平无年龄和性別的差异;FEP与Hb之间呈负相关,r=-0.6784(P<0.01);诊断铁缺乏症的灵敏性为87％,特异性88％,与Hb的诊断符合串为81％。同时比较了国产930型简易荧光计与日本F-3000型荧光分光光度计测定FEP效果,其结果基本一致,但930机测定值离散度较大。     

红细胞中游离原卟啉的荧光光度测定方法研究

本文报道了用荧光光度法测定血液红细胞中游离原卟啉(FEP)含量。方法线性范围在0.01～0.1μg,r=0.9998,检测限0.001μg FEP,批间精密度变异系数(C.V.)4.3%～7%。相对回收率96.6%。本法和荧光分光光度法测定结果之相关系数r=0.9796,P<0.001,有非常显著意义。     

红细胞游离原卟啉正常值探讨

<正> 红细胞游离原卟啉(FEP)是诊断早期铁缺乏的灵敏指标。应用纸片法测定以来,FEP测定在发现早期缺铁和铁缺乏防治效果的评价中应用更为广泛。但关于FEP正常值国内外至今无统一标准,各家提出的建议值相互差别较大。为探讨适合我国人群的FEP正常值,于1988年结合《我国儿童青少年贫血筛选标准的研究》,     

荧光分光法测定红细胞内原卟啉

本文对荧光法测定血原卟啉的方法进行了验证,并且进行了方法的回收与重现性试验。在此基础上进了实际应用,比较补铁药前后原卟啉含量及铅作业工人与学生原卟啉含量情况。实验部分:(1)荧光强度与标准系列线性关系:FEP的荧光强度值呈现良好的线性关系,符合郎佰比尔定律,相关系数(r)=0.9981。(2)重现性试验:用10份样品重复做10次:试验的结果的变异0～9.0％之间,样品重复变异在±5％之间。(3)回收试验:在4个样品中加入20μg、40μg、60μg、80μgFEP标准液,测的结果减去本底。实验表明回收率90～105％之间。应用:(1)铅作业工人与学生血原卟啉含量比较:工人血原卟啉平均值52.88μmol/L学生血原卟啉含量平均值29.96μmol/L,工人比学生高22.92μmol/L。经统计学处理P<0.01有高度显著性,实验表明铅中毒均可使原卟啉增高。(2)补铁药前后血原卟啉的比较:经统计学处理,服药前与服药后P<0.05有显著性差异。实验证明,补铁后血原卟啉方法简单,灵敏度高,线性范围宽,线性关系良好。实际应用表明,原卟啉可作为铅作业工人接触指标。学生通过补铁药前后,表明原卟啉是缺铁性贫血的主要诊断指标。     

铅对作业工人血中游离原卟啉的影响

铅吸收和铅中毒者可影响卟啉原转化为血红素,导致血红蛋白的合成障碍。本文选择的正常人群组与对照组平均年龄、平均工龄及性别比较,,差异均无显著性意义(P>0.05)。通过测定上述两组人群血中游离原卟啉的FEP结果如下: 测定178名正常人(男性95名,女性83名)的血红细胞游离原卟啉含量。总均值57.36μg/100 ml:男性均值52.72μg/100ml,女性均值62.67μg/100 ml。 测定153名铅作业工人(男性87名,女性66名)的血红细胞游离原卟啉含量,总均值147.8μg/100ml;男性均值138.3     

高效液相色谱法同时测定全血中的原卟啉和锌原卟啉

目的 建立可同时测定全血中原卟啉和锌原卟啉的高效液相色谱-荧光检测法。方法 优化流动相、色谱柱、样品处理方法等,确定最佳参数。采用荧光检测器扫描选取最佳激发和发射波长。以保留时间定性,外标法定量,绘制标准工作曲线。计算方法的检出限、定量限、准确度、精密度、重复性和重现性。结果 经优化,取血样30μl,加入170μl纯净水稀释,经涡旋混合器混匀,加入1.0 ml甲醇,涡旋混匀沉淀蛋白,于涡旋振荡器上混匀5 min,超声提取20 min, 15 289×g离心5 min,吸取上清液,50μl上机测定。采用反相键合固定相色谱柱Thermo Acclaim^TM 120 C₁₈(250 mm×4.6 mm, 5μm 120?)分离,50 mmol/L乙酸铵水溶液(pH=6.0)和甲醇等度洗脱,原卟啉和锌原卟啉最适的激发/发射波长分别为396 nm/625 nm、411 nm/581 nm。原卟啉和锌原卟啉在1.0～50μg/L浓度范围内线性均良好(r值均>0.999);检出限均为12μg/L,定量限均为40μg/L;以抗凝牛全血为基质,在低、中、...     

荧光分光光度法测定微量血中游离原卟啉

血中游离原卟啉(FEP)是筛查铅中毒的首选指标，在环境铅污染与人体效应检测中具有重要应用价值。本试验应用荧光分光盘度法测定血中游离原卟啉．为其推广应用进行论证。     

广州地区小儿全血锌原卟啉测定的正常值探讨

本文报告536例正常小儿全血锌原卟啉的测定值.结果显示,不同年龄小儿血锌原卟啉值有所不同,随着年龄增长,血锌原卟啉值有逐渐下降趋势。本组小于2岁的锌原叶啉正常参考值为0.7622μmol/L,大于2岁的正常参考值为0.6650μmol/L.男女性别有差异.女性(均值为0.5845±0.1064μmol/L)高于男性(均值为0.5657±0.1115μmol/L),(P<0.05).建议应用血锌原卟啉作为判断红细胞生成缺铁的指标时,应考虑不同地区、不同年龄和性别的差异性.     

449例血液锌原卟啉测定结果分析

铅中毒和缺铁性贫血时体内红细胞锌原卟啉(ZPP)水平升高,1979年世界卫生组织已将血液锌原卟啉列为铅中毒诊断指标之一,因其操作简便、快速、重复性好,目前已被众多国家广为采用[1]。我国已于1989年将血液锌原卟啉列为慢性铅中毒诊断指标之一。为了解ZPP与其它铅中毒实验室诊断指标的关系及男女性别之间的差异,对356例触铅工人ZPP、尿Pb.尿σ-ALA测定结果及93例非触铅工人ZPP的测定结果分析如下。1　对象与方法1.1　对象　非触铅工人93人,年龄19～50岁,男55人,女25人;触铅工人356人,年龄20～52岁,其中蓄电池制造工人104人,男70人,女34…     

铅接触者职业健康监护血锌原卟啉筛选指标值的探讨

目的探讨铅接触者职业健康监护中血锌原卟啉作为筛选指标的可行性。方法以某蓄电池制造企业2000-2001年极板、装配、化成3个车间各工段的作业场所空气铅烟（尘）监测数据456个及上述3个车间198名职工近2年体检结果为资料进行统计分析。结果各浓度组血锌原卟啉、尿铅值均有随接触浓度增高而增大的趋势；浓度与血锌原卟咻、浓度与尿铅及血锌原卟啉与尿铅之间均呈高度正相关（P〈0．01）。从而提示血锌原卟啉值的变化可间接地反映尿铅值的变化，建立血锌原卟啉与尿铅值的数学模型为Pi^=0．1612×Zi0.7354。若将漏诊率控制在1％左右，经模型推算出血锌原卟啉的值为1．7μmol／L（1062．5μg／L），若血红蛋白值取170g／L（本资料平均值）时，血锌原卟啉值约为6μg／g Hb（1062．5／170）。结论建议血锌原卟啉可以作为筛选指标，其下限值应为6μg／g Hb。     

Free erythrocyte protoporphyrin (FEP) and zinc protoporphyrin (ZnP) as biological parameters for lead poisoning

Summary Lamola et al. (1974) reported that free erythrocyte protoporphyrin (FEP) is not present as free type protoporphyrin (FPP) but rather is chelated with zinc in lead poisoning and iron deficiency anemia. In our fluorometric study of FEP and zinc protoporphyrin (ZnP) in erythrocytes of lead-poisoned rabbits and lead workers, the co-existence of ZnP and FPP was observed in the severe stage of acute lead poisoning in rabbits. The ratio of ZnP to FEP in erythrocytes decreased with the progress of lead intoxication, and the amount of FPP was greater than that of ZnP in the severe stage of intoxication. This FPP accumulated in the erythrocytes was easily converted to ZnP by incubation of the hemolysate with zinc. On the other hand, increased protoporphyrin (PP) in bone marrow was present as FPP in lead intoxication. From these results, ZnP in peripheral erythrocytes is considered to be a secondary product, not a primary one. Therefore, the determination of total FEP (FPP + ZnP) by the acid solvent extraction method might be more reasonable than using ZnP-determination as the biological parameter of lead poisoning. We propose that erythrocyte porphyrin in lead intoxication should be expressed as FEP, not as ZnP, for the parameter. The present study also suggests that the form of erythrocyte FPP in erythropoietic protoporphyria (EPP) patients is a little different from that in lead-poisoning patients, because of its high chelation reactivity with zinc.     

Influence of heavy metal mixtures on erythrocyte metabolism

Summary Exposure of foundry workers to mixtures of different heavy metals is a very important toxicological problem. In this paper the estimation of the effects of lead, zinc, and copper on erythrocyte metabolism is presented. Concentrations of copper and zinc at work posts of the group examined did not exceed TLV, while lead concentration was 1.5 to 4 times higher than TLV. Erythrocyte metabolism was measured through activities of such glycolytic pathway enzymes as PFK, PGI, PK, aldolase and G6-PD from the hexose monophosphate pathway. Additionally the free erythrocyte protoporphyrin (FEP) level, D-ALA activity, serum GSH level, 2,3 DPG level in erythrocytes and lactic acid production during a 2-h incubation of red blood cells (RBC) was estimated. The blood-lead level, FEP level, copper concentration in erythrocytes in exposed group were significantly higher than in control group while the zinc level in erythrocytes was significantly lower. Measuring erythrocyte metabolism we showed that the activity of PGI, PFK, aldolase, lactic production and 2,3 DPG levels was significantly higher in the exposed group, probably as a result of anaerobic glycolysis activation.     

The free erythrocyte protoporphyrin assay in monitoring lead-exposed workers

Summary We have performed a comparative analysis of two different fluorometric methods used to determine free erythrocyte protoporphyrin (FEP) blood concentration. The first method is based on an extractive procedure, whereas the second one involves the direct fluorometric analysis of whole blood. Our results show that the extractive procedure is probably the most reliable technique available for FEP determination, but it is not so suitable for mass screening, whereas the direct fluorometric determination of FEP blood concentration is probably less reliable, but sufficiently enough to be used for mass screening. We have furthermore investigated whether the FEP test could be used as a unique monitoring method for subclinical lead poisoning. Our findings indicate that FEP test can detect very early metabolic alterations, but it is not so suitable for determining lead absorption and should therefore be used in mass screening together with a dose indicator, such as blood lead concentration.     

The relationship between zinc protoporphyrin (ZPP) and “free” erythrocyte protoporphyrin (FEP) in lead-exposed individuals

Summary The relationship between zinc protoporphyrin (ZPP) and total erythrocyte protoporphyrin, measured as free erythrocyte protoporphyrin (FEP), was determined in 194 adult subjects with different occupational and non-occupational lead exposures. Furthermore, the ZPP-FEP comparison was considered with respect to the dose-effect relationship of ZPP and FEP with blood lead (PbB) for males and females, respectively. Bilirubin (Bil.) interferences in ZPP analysis were taken into account. A very close and highly significant relationship (r=0.962, P<0.001) was established between ZPP and FEP values. A significant correlation (P<0.001) between log ZPP or log FEP and PbB (malesr=0.767 and 0.718; femalesr=0.525 and 0.405) was also found. It was established, by both in vitro and in vivo studies, that Bil. interferes with the ZPP fluorescence readings; the relationship between false positive ZPP concentrations and Bil. concentrations (in vitror=0.987, in vivor=0.903) was highly significant (P<0.001). A small but highly significant (r=0.948,P<0.001) influence of increased carboxyhemoglobin (COHb) concentrations on the decrease in hematofluorometer ZPP readings, due to inadequate oxygenation of the blood, was found. The results obtained confirm the usefulness of ZPP determinations using hematofluorometers for surveillance of increased lead absorption but stress that the interfering effect of Bil., and to a lesser extent of COW cannot be ignored.The authors, who share equal responsibility for this paper, have been placed in alphabetical order     

Effect of estradiol on heme biosynthetic pathway in lead-poisoned rabbits

Objectives To clarify the effect of the female hormone estradiol (Est) on heme biosynthesis in lead-poisoned rabbits, parameters indicating lead exposure, such as free erythrocyte protoporphyrin (FEP) level and δ-aminolevulinic acid dehydratase (ALA-D) activity, were determined. Methods Twenty-six male Japanese white rabbits (body weight (BW), 3kg) were divided into four groups: I (control), II (Est), III (Pb), IV (Est+Pb). About 3 weeks after castration, Est (3 mg/kg of BW) was injected intramuscularly, and 2 weeks thereafter, lead (1.2 mg/kg of BW) was injected intravenously. After the initial injection of each of these substances, the same dose of each of these substances was injected once a week until the 9th week. Results In groups III and IV, FEP level increased and ALA-D activity in the erythrocytes, bone marrow and liver decreased with an increase in lead concentration in blood. FEP level decreased significantly (p<0.01) in the 8th and 10th weeks after Est injection in group IV compared to with that in group III and was not elevated in group II compared with that in group I. ALA-D activity in the erythrocytes, bone marrow and liver increased significantly in group II compared with that in group I, whereas Ht and Hb levels decreased in group II compared with those in group I, and decreased in group IV compared with those in group III. The level of iron in plasma (Fe−P) was within the normal range during experiment. Conclusions In this study, Est did not increase FEP level. From the above results regarding FEP level and ALA-D activity, Est may prevent an increase in FEP level caused by lead. Ht and Hb levels, which are the parameters of anemia, decreased mainly as a result of Est exposure rather than lead exposure.     

Relationships between three indicators of lead exposure in workers: Blood lead, δ-aminolevulinic acid and free Erythrocyte Protoporphyrin

Summary Whole blood lead (Pb-B), urinary -aminolevulinic acid (ALA-U) and free erythrocyte protoporphyrin (FEP) were measured in three groups of workers (n = 196) with different degrees of exposure to lead, and one group of men with no previous exposure to the metal (n = 48). Inter-group comparison showed a correlation of r = 0.73 between Pb-B and log of ALA-U, and r = 0.91 between Pb-B and log of FEP. ALA-U and FEP values rose sharply after Pb-B values reached 450–500 g/1.     

Biological response of children to low levels of inorganic lead

Blood lead level (Pb-B), erythrocyte δ-aminolevulinic acid dehydratase (ALA-D), zinc protoporphyrin (ZnPP), and free-erythrocyte porphyrin (FEP) were compared for groups of children of the nursery and primary school living near a lead smelter and in a village 4 km from the factory. A definite increase of Pb-B levels was found in the children living near the lead smelter, who proved to have average values about twice those of the control groups: 17.3 ± 6.9 μg/100 ml for the nursery school and 16.9 ± 5.5 μg/100 ml for the primary school children against 8.7 ± 2.8 and 7.6 ± 2.9 μg/100 ml for the respective controls. A significant decrease of ALA-D activity and an increase of FEP values were demonstrated among the children exposed. For FEP a graded response was evidenced at Pb-B levels ranging between 10 and 20 μg/100 ml blood so that the no-response level in children seems to be lower than 10 μg/100 ml of Pb-B.     

Erythrocyte Protoporphyrin Test for Occupational Lead Exposure

? Determination of erythrocyte protoporphyrin levels was performed in workers who are occupationally exposed to lead. The level of erythrocyte protoporphyrin was easily measured with microsamples of blood by utilizing a fluorescent assay. The log of erythrocyte protoporphyrin level was closely correlated to blood lead level (r=.72) in lead-exposed workers. The erythrocyte protoporphyrin test is especially useful in the detection of mild increases in blood lead concentration under conditions of occupational exposure.