铅作业工人尿N—乙酰—β—D—氨基葡糖苷酸同工酶活性的研究

本文对２２７名铅作业工人的肾功能和卟啉代谢状况进行了研究。结果表明卟啉代谢紊乱先于铅中毒性肾损害，铅接触组的尿ＮＡＧ－Ａ活性显著低于对照组，而尿ＮＡＧ－Ｂ明显变人；ＮＡＧ－Ａ活性下降是反映铅中毒肾损害较敏感的指标，其检测价值比尿总ＮＡＧ测定大。尿ＮＡＧ－Ａ活性检测可作为铅中毒性肾损害的监测指标。     

铅作业工人尿中γ—谷氨酰移换酶活性的研究

对218名铅作业工人的肾功能和卟啉代谢状况进行了研究,果表明尿γ谷氨酰移换酶(γ-GT)活性下降与尿铅浓度和铅中毒程度无明显相关;尿γ-GT活性下降是反映铅中毒性肾损害的敏感指标。尿γ—GT检测可作为铅中毒性肾损害的监测指标。     

铅中毒实验室检查指标的应用和探讨

对110例在我院同时进行血铅、尿铅、诊断性驱铅试验、尿d-氨基-γ-酮戊酸和锌原卟啉等检查的病例检查结果进行比较和分析。结果显示,观察对象筛查中血铅的灵敏度73.77%,尿铅为37.70%,诊断性驱铅试验80.33%;轻度铅中毒病人筛查中ZPP灵敏度最高（81.82%）,诊断性驱铅试验特异度、准确度和阳性预测值均最高（分别为100%、88.18%和100%）。提示只采用单项检测指标筛查观察对象或诊断铅中毒,容易出现漏诊或误诊,应将几项指标联合应用。     

铅作业工人FEP检测结果分析

应用检测红细胞游离原卟啉的方法, 对铅作业工人进行铅吸收及铅中毒筛检, 并将该方法与尿铅检测进行了比较。     

关于尿铅和血铅测定中几个问题的讨论

尿铅和血铅均是国家职业卫生标准GBZ3 7-2 0 0 2职业性慢性铅中毒的实验室检测指标。亦是铅作业人员的职业性健康检查的必查项目。然而作为预防铅对儿童健康的危害,是选择检测尿铅还是血铅,如何评定检测结果是值得讨论的。1　尿铅及血铅测定的意义1.1　尿铅是反映近期铅接触水平的敏感指标,取样方便,与血铅、尿δ-氨基-Γ-酮戊酸、血锌原卟啉显著相关,尿铅的测定积累了丰富的经验,研制出了性能良好,价格便宜的仪器,尿铅的测定准确可靠,尿铅结果与临床表现亦相关,驱铅试验认为是目前较好的反映体内铅负荷的检测方法,尤其对已脱离钳接触人员…     

铅作业工人肾损害早期指标研究

目的：探讨铅作业工人肾脏损害的早期指标及其临床意义。方法：80名铅作业工人分为铅接触正常组、铅吸收组、慢性轻度铅中毒组,并以无铅接触史的43名健康成人作为对照组。分别测定血铅(PbB)、尿铅(PbU)、血红细胞游离原叶啉(FEP)、尿δ—氨基酮戊酸(δ-ALA)、尿β2-微球蛋白(β2-MG)、尿N-乙酰-β-D氨基葡萄糖苷酶(NAG)、尿视黄醇结合蛋白(RBP)。结果 铅作业工人PbB、PbU、H0、δ-ALA、NAG、RBP均显著高于对照组;β2-MG虽亦高于对照组,但差别无显著性。结论:长期职业性铅接触可造成肾功能损害,尿NAG、RBP可作为铅中毒肾损害早期敏感的监测指标。     

FEP在职业性铅中毒诊断中的合适度

ＦＥＰ在职业性铅中毒诊断中的合适度徐州市职业病防治院（２２１００５）殷永祥徐州市儿童保健所王文洁红细胞游离原卟啉（ＦＥＰ）作为职业性慢性铅中毒诊断指标之一，临床上用诊断性驱铅试验的尿铅值来诊断铅中毒更有意义，但后者操作复杂。我们探讨ＦＥＰ与驱铅后尿铅...     

铬作业工人尿γ—谷氨酰移换酶活性的研究

本文对47名铬作业工人的肾功能状况进行了研究。结果表明γ-GT活性增加是反映铬中毒性肾损害的敏感指标之一。尿γ-GT活性与尿铬、尿蛋白和β_2-MG含量呈显著性相关。因此,尿γ-GT活性检测可作为铬性肾损害的监测指标。     

铅中毒实验室检查指标的应用和探讨

对110例在我院同时进行血铅、尿铅、诊断性驱铅试验、尿d-氨基-γ-酮戊酸和锌原卟啉等检查的病例检查结果进行比较和分析。结果显示,观察对象筛查中血铅的灵敏度为7377%,尿铅为3770%,诊断性驱铅试验8033%;轻度铅中毒病人筛查中ZPP灵敏度最高(8182%),诊断性驱铅试验特异度、准确度和阳性预测值均最高(分别为100%、8818%和100%)。提示只采用单项检测指标筛查观察对象或诊断铅中毒,容易出现漏诊或误诊,应将几项指标联合应用。     

铅中毒肾损害早期检测的实验研究

雄性大鼠腹腔注射醋酸铅5mg/kg 体重,5次/周、连续12周,肾脏出现明显的形态和功能异常。尿r-GT 活性降低是最早出现的改变,其阳性检出率也较尿蛋白、尿糖为高。表明尿r-GT 作为铅中毒肾损害的早期检测指标有一定价值,但对其特异性有待进一步研究。     

Occupational exposure to toluene and its possible causative role in renal damage development in shoe workers

Objectives: An important, although, unprecise number of shoe workers in Leon, Mexico, are in continuous contact with toluene-based glues. The induction of renal glomerular and/or tubular lesions as a result of toluene exposure is still being discussed controversially. Our objective was to evaluate the extent of occupational exposure, assessing urinary o-Cresol excretion as a measure for toluene exposure in a population at risk as compared to a control population. Urinary albumin excretion (UAE) and N-acetyl-β-D-glucosaminidase (NAG) enzymatic activity were tested to assess renal dysfunction. Methods: A cross-sectional study was performed comparing 50 toluene-exposed shoe workers and 25 control subjects. Urinary o-cresol was assessed on first and last day of labor week from exposed subjects. A single urine sample was obtained from control subjects. Urinary Albumin excretion (UAE) and (NAG) activity were examined in 12 h urine samples in all subjects. Urine and serum creatinine were measured to asses renal function. Results: At the end of the labor week, urinary o-cresol levels were higher in samples obtained from exposed subjects. Albumin excretion was similar in the exposed and control groups. NAG activity was greater in the exposed group compared to control group (median 3.5 U/g creatinine vs 1.9 U/g creatinine, z=2.6, P=0.009). An inverse relationship was found between schooling years and the NAG enzymatic activity for the two studied groups (r= −0.27, P=0.02), Conclusions: Our findings support the hypothesis that toluene may be a factor associated with the presence of renal damage in exposed shoe workers. As NAG activity is increased, we believe the lesion initiates in the renal tubular cells.     

Renal tubular function of workers exposed to low levels of cadmium

Cadmium induced renal tubular effects were examined in 65 female workers in a factory manufacturing nickel cadmium batteries. Urinary beta 2-microglobulin (beta 2m), urinary N-acetyl-D-glucosaminidase activity (NAG), and serum creatinine and serum urea concentrations were used to assess the renal effects. Of the four measures, only urinary NAG and urinary beta 2m showed a strong positive correlation with blood cadmium concentrations (r = 0.49 and 0.43 respectively); NAG showed a weaker correlation with urinary cadmium concentrations (r = 0.35). Urinary beta 2m has weak correlation with urinary cadmium (r = 0.04). Only urinary NAG showed a significant deterioration in renal function among the exposed group. NAG detects the largest proportion of abnormalities among the exposed group. Abnormal urinary beta 2m is detected in only 15.4% of the workers, half of whom have blood cadmium above 10 micrograms/l. The proportion of abnormalities detected by urinary NAG differs significantly from the proportion of abnormalities detected by urinary beta 2m (p less than 0.01). The age adjusted mean urinary NAG excretion showed a significant rise with urinary cadmium of above 3 micrograms/g creatinine. Urinary beta 2m failed to show any significant rise. With blood cadmium concentrations, the age adjusted mean urinary NAG excretion showed a rise from 1 microgram/l of blood cadmium followed by a plateau between blood cadmium concentrations of 3-10 micrograms/l. No significant rise in mean urinary excretion in beta 2m was seen until blood cadmium concentrations exceeded 10 micrograms/l.     

Renal tubular function of workers exposed to low levels of cadmium.

Cadmium induced renal tubular effects were examined in 65 female workers in a factory manufacturing nickel cadmium batteries. Urinary beta 2-microglobulin (beta 2m), urinary N-acetyl-D-glucosaminidase activity (NAG), and serum creatinine and serum urea concentrations were used to assess the renal effects. Of the four measures, only urinary NAG and urinary beta 2m showed a strong positive correlation with blood cadmium concentrations (r = 0.49 and 0.43 respectively); NAG showed a weaker correlation with urinary cadmium concentrations (r = 0.35). Urinary beta 2m has weak correlation with urinary cadmium (r = 0.04). Only urinary NAG showed a significant deterioration in renal function among the exposed group. NAG detects the largest proportion of abnormalities among the exposed group. Abnormal urinary beta 2m is detected in only 15.4% of the workers, half of whom have blood cadmium above 10 micrograms/l. The proportion of abnormalities detected by urinary NAG differs significantly from the proportion of abnormalities detected by urinary beta 2m (p less than 0.01). The age adjusted mean urinary NAG excretion showed a significant rise with urinary cadmium of above 3 micrograms/g creatinine. Urinary beta 2m failed to show any significant rise. With blood cadmium concentrations, the age adjusted mean urinary NAG excretion showed a rise from 1 microgram/l of blood cadmium followed by a plateau between blood cadmium concentrations of 3-10 micrograms/l. No significant rise in mean urinary excretion in beta 2m was seen until blood cadmium concentrations exceeded 10 micrograms/l.     

Change in the iso-enzyme profiles of urinary N-acetyl-beta-D-glucosoaminidase in workers exposed to mercury

The iso-enzyme profiles of urinary N-acetyl-beta-D-glucosoaminidase (NAG) were studied in the workers from a chloro-alkaline electrolysis plant that had been continuously exposed to elemental mercury. The same workers then had a work break of four months and were later re-exposed to mercury for another five months. The activities of urinary NAG in workers exposed to mercury before and after the work break and in the control group were 2.09 +/- 1.03 IU/L; 0.90 +/- 0.52 IU/L and 1.13 +/- 0.35 IU/L, respectively. The fraction of the dominant A form activity in the total activity, in the workers exposed to mercury after a work break (85.31 +/- 5.32%), was almost equal to the fraction of A in the control group (84.64 +/- 2.75%). The percent fraction of A forms (A and A2) during continuous exposure was almost equal to the sum of the fractions A and A2 in the control group and for exposure after the work break. The fraction of the B form activity in the total activity during exposure to elemental mercury for five months after the work break (7.41 +/- 3.45%) was lower (P < 0.1) than the fraction of the B form in the control group (8.62 +/- 2.19%). The decrease in the fraction of the B form compared with the control group was more significant (P < 0.001) in the case of continuously exposed workers (5.25 +/- 2.55%). Beside the major A and B iso-enzymes of NAG, the A2 form was also isolated, and its fraction in the control group (6.73 +/- 2.15%) was not negligible. For workers exposed to mercury for five months, it was 7.28 +/- 3.52%. It is concluded that mercury affected the increased exocytosis of iso-enzyme A and the inhibition of B iso-enzyme of NAG. The increase in activity of urinary NAG in subjects exposed to mercury was a consequence of the increased excretion of A form. It was established also that the four months work break was sufficient for the repair of renal damages that occurred during continuous exposure, and which were monitored by the activity of NAG. Thus, the effects of mercury seem to have been reversible.     

职业接触汞工人肾脏早期损伤指标的探讨

目的　探讨职业接触汞工人肾损伤的早期监控指标。方法　尿汞 (HgU)采用二硫腙化学法测定 ,尿视黄醇结合蛋白 (RBP)、尿 β2 微球蛋白 (β2 MG)和尿微量白蛋白 (mALB)采用全定量酶免疫法测定 ,尿N 乙酰 β D 氨基葡萄糖苷酶 (NAG)和γ 谷氨酰基转移酶 (γ GT)采用速率法测定 ,尿肌酐(Cr)采用苦味酸法测定。结果　职业接触汞工人尿RBP、β2 MG、NAG、γ GT测定结果分别为 (4 39.7±2 0 1.4 )、(14 1.4± 5 6 .3) μg gCr,(12 .3± 5 .7)、(6 0 .3± 18.5 )U gCr,均高于对照组 [分别为 (2 4 3.2±16 9.1)、(88.6± 4 1.2 ) μg gCr,(8.2± 1.6 )、(4 1.3± 13.2 )U gCr],差异均有显著性 (P <0 .0 5 ,P <0 .0 1)。随尿汞含量增加上述指标有逐渐增高的趋势 ;单项及两项检测RBP、β2 MG、NAG、γ GT的阳性率较低 ,联合其中 3项检测阳性率较高 ,联合 4项检测阳性率可达 85 .5 %。结论　联合检测RBP、β2 MG、NAG、γ GT是诊断职业接触汞工人早期肾损伤的灵敏指标。     

尿生化指标检测在肾功能早期改变中的诊断价值

目的探讨尿生化指标检测在肾功能早期改变中的诊断价值。方法将青龙县人民医院2010年8月-2011年3月收治的100例肾病患者为研究对象,按照肾小球滤过率（GFR）的大小,将其分为肾功能正常组38例（A组）,肾功能损害组62例（B组）,另选取健康体检者40例作为对照组,测定肾病组患者治疗前后及对照组的尿胱抑素C（Cy-sC）、尿N-乙酰-D-D氨基葡萄糖苷酶（NAG）、尿β2-微球蛋白（β2-MG）、尿比重（SG）。结果肾病组的尿CysC、NAG、β2-MG显著高于对照组（P〈0.05）,尿SG显著低于对照组（P〈0.05）;B组的尿CysC、NAG、2β-MG显著高于A组（P〈0.05）,尿SG显著低于A组（P〈0.05）;肾病组经治疗后尿CysC、NAG、β2-MG较治疗前显著降低,尿SG较治疗前显著升高（P〈0.05）。结论尿生化指标可作为肾功能损害较好的检测诊断指标,在一定程度上可反映病情的严重程度,且操作简便,值得临床推广。     

铅作业工人肾损伤某些生化指标的变化

目的　探索铅致肾损伤生化指标的变化。方法　观察了某蓄电池厂 10 3名铅作业工人尿总蛋白(TP)、尿β2 微球蛋白 (β2 MG)、尿N 乙酰 β D 氨基葡萄糖苷酶 (NAG)的变化 ,同时分析尿铅含量、接触工龄与三指标的关系。结果　接触组尿TP(5 9 73± 6 84 )mg gCr、尿 β2 MG(12 2 0 1± 1 2 5 ) μg gCr、尿NAG(13 70±1 6 2 )U gCr水平显著高于对照组 ,且随尿铅含量的增高而升高。尿NAG的活性在接触铅 1～ 3年明显高于对照组 ,先于尿TP、尿 β2 MG出现异常。结论　尿NAG活性升高可能反映肾小管细胞损伤。尿NAG活性变化 ,结合尿β2 MG或尿TP的变化 ,可能反映肾受损情况。     

Lead exposure and urinary N-acetyl beta D glucosaminidase activity in adolescent workers in auto repair workshops.

PURPOSE: To investigate levels of lead (Pb) exposure and renal tubular damage among adolescent workers in auto repair workshops in Turkey. METHODS: The study was conducted on 39 adolescent workers (mean age: 16.18 +/- 3.19 years) in auto repair workshops (8 autoelectrician, 10 motor repairman, 8 auto painter, 5 turner, 8 bonnet straighter). Thirteen adult employees of battery production in the workshops (mean age: 32.08 +/- 10.94 years) and 29 healthy rural adolescent (mean age: 14.78 +/- 2.68 years) constituted the control groups. The level of blood Pb was investigated by an atomic absorption spectrophotometer and urinary N-acetyl beta- D glucosaminidase (NAG) activity was measured by a colorimetric method. Mann-Whitney U test was performed to examine group differences. RESULTS: All subjects and controls had normal blood urea, creatinine, uric acid, sodium, potassium levels, normal routine urine examination and tubular phosphorus reabsorption. Blood Pb levels in auto repair workers (8.13 +/- 7.41 mug/dL) were significantly higher than the rural control group (3.49 +/- 1.39 mug/dL) but lower than the battery workers (25.27 +/- 9.82 mug/dL). Urinary NAG (U/gr creatinine) (4.71 +/- 2.11) was lower than the battery workers (7.39 +/- 4.37), however significantly higher than the normal control group (3.07 +/- 1.20). In addition, auto painters had higher levels of Pb exposure and urinary NAG activity than the other workers (p <.05). CONCLUSION: Chronic low dose Pb exposure was found to cause renal tubular injury in children workers of auto repair workshops.     

Urinary N-acetyl-beta-D-glucosaminidase activity in workers exposed to inorganic lead.

Urinary N-acetyl-beta-D-glucosaminidase (NAG) had been shown to be a useful early marker of renal injury. In workers exposed to lead it seems to be the only early marker but the dose response and dose effect relations are weak. Furthermore, the significance and underlying mechanism of increased urinary NAG activity is far from clear. By studying the isoenzyme profiles of urinary NAG, the significance and underlying mechanism may be further clarified. The heat labile (NAG-A) and heat stable (NAG-B) isoenzyme profiles of 128 workers exposed to lead from a lead stabiliser factory were analysed. NAG activity was expressed as total NAG, NAG-A, and NAG-B activity as well as ratios (NAG-B/total NAG and NAG-B/NAG-A). Exposure indices included the recent concentration of blood lead (BPb), a cumulative blood lead index (TBPb), and the recent change in concentration of blood lead (CBPb). The NAG indices correlated best with CBPb. Nearly 50% of the variation in NAG-B activity could be explained by the combination of all three exposure indices but only the CBPb was highly significant. When these exposure indices were entered separately into the regression equation, CBPb accounted for 36.3% of the variation in NAG-B activity, 5.7% was accounted for by TBPb and 2.7% by BPb. There was also no dose-effect or dose-response relation between the NAG variables and BPb or TBPb groups. With CBPb, there were dose-effect and dose-response relations. With CBPb, there was an increase in NAG variables in the group with more than 25% increase in blood lead over the past six months. The increase in NAG activity in this study is likely to be due to a recent increase in concentration of blood lead and hence presumably a recent rise in renal burden of inorganic lead. This suggests that the increase in urinary NAG activity is a form of acute response to a sharp increase in renal burden of lead, rather than to a cumulative dose. Heat stable NAG is part of the lysosomal membrane and is present in the urine when there is breakdown of lysosomes. Our data therefore contradict suggestions that the increase in urinary NAG activity is due to exocytosis.     

A nine year follow up study of renal effects in workers exposed to cadmium in a zinc ore refinery.

Renal changes with time have been studied in 14 workers engaged in the production of cadmium (Cd) in a zinc ore refinery. These workers were examined once a year in the period 1980 to 1985 and 13 of them also in 1989. Four of the workers (group A) had been employed in an old Cd plant before 1973 and had received higher exposures to Cd than the other workers (group B). Average urinary Cd concentrations over the whole study period in workers of group A ranged from 6.9 to 9.2 micrograms/g creatinine (median 8.4 micrograms/g) and in workers of group B from 0.64 to 7.1 micrograms/g creatinine (median 1.9 micrograms/g). Renal effects were assessed by the determination of urinary N-acetyl-beta-D-glucosaminidase (NAG), beta 2-microglobulin (beta 2-M), retinol binding protein, albumin, total protein, and serum creatinine concentrations and activity. Urinary beta 2-M concentrations in three of four workers of group A were close to or marginally above the upper normal limit during the study period. The beta 2-microglobinuria was not, however, progressive. No values outside normal limits were detected for any of the other renal tests in workers of groups A and B, related to exposure to Cd. Dose-response relations showed that urinary Cd correlated significantly with urinary NAG activity and total protein and beta 2-M. The earliest change induced by Cd was seen for urinary NAG activity within normal limits of NAG excretion. The regression lines were similar in the surveys between 1981 and 1989, indicative of no progression to higher values for any of the renal tests. The current biological exposure index (BEI) of 10 micrograms/g creatinine for workers exposed to Cd, set by the American Conference of Governmental Industrial Hygienists (ACGIH), therefore seems justified, although the safety margin is small. The World Health Organisation recommended limit and ACGIH (1992-3) proposed limit of 5 micrograms/g creatinine would provide a much larger safety margin, and could be regarded as an action point for increased health surveillance.