骨矿物质含量作为镉致骨损伤早期诊断指标研究

本文用Ｘ线光密度法测量了２０２例镉接触工人和５２６例当地无镉接触史健康居民的桡骨和尺骨的中远１／３交界处及远端１／１０交界处骨矿含量。结果表明，暴露组各部位骨矿含量显著低于对照组各部位的骨矿含量，且骨矿含量与肾损伤指标之间有很好的相关怀．骨矿含量随匐接触年限的增加而降低，尿镉越高，骨矿含量越低。用桡骨远端１／１０交界处的骨矿含量来诊断镉所引起的骨质损伤效果较好，其诊断灵敏度、特异度及与肾损伤诊断结果的符合率均较好，故推荐用桡骨远端１／１０交界处骨矿含量作为镉致骨损伤的一顶早期诊断指标。     

镉接触者骨矿物质含量改变及其诊断价值

本文用Ｘ线光密度法测量了２０２例镉接触工人和５２６例当地无镉接触史的健康居民的桡骨和尺骨的中远１／３交界处及超远端的骨矿含量。结果表明：接触组各部位骨矿含量显著低于对照组各部位的骨矿含量，且骨矿含量特别是桡骨超远端骨矿含量与肾损伤指标之间有很了的相关性，桡骨超远端骨矿含量的诊断结果与肾损伤指标的诊断结果的符合率达９４％，故推荐用桡骨超远端骨矿含量作为镉致骨损伤的一项早期诊断指标。     

职业镉接触者骨损伤指标分析

用改进Ｘ线光密度法检测２０２例镉接触工人桡骨中远端１／３处骨矿含量，发现镉接触工人骨矿含量与对照组对比显著下降。骨矿含量与尿镉，尿Ｎ－乙酰－β－Ｄ所基葡萄糖苷酶呈负相关，用肌指标＋肾指标诊断镉伤害“病人”。，诊断特异度１００％，误诊率为零。     

镉接触工人桡骨远端骨质结构X线分析

本文通过对镉暴露工人桡骨远端骨质结构Ｘ线分析发现，镉暴露工人桡骨远端小梁明显稀疏。用骨小梁数目、平均宽度、相对密度和相对面积四项指标来反映匐所引起的骨质损害。结果表明：上述骨小梁不尿镉、尿ＮＡＧ、尿钙、尿β２－微球蛋白有明显相关性，其中骨小数目、平均宽度及相对面积与尿镉有明显的剂量－反应关系。建议使用骨小梁数目＋骨小梁平均宽度二联指标作为镉致骨损伤的早期诊断指标。     

镉作业工人骨质改变的调查

利用Ｘ线光密度法观察镉作业工人的早期骨质改变。选镉镍电池厂镉作业工人２０７人,对照组５２８人,测定桡骨超远端和桡骨中远端１／３交界处矿物质含量,同时取晨尿测定尿镉、尿钙、尿β２－微球蛋白,尿Ｎ－乙酰－β－Ｄ氨基葡萄糖苷酶。结果表明,不同性别２镉接触组的骨矿物质含量均低于对照组。但骨矿物质含量与尿镉、尿钙、尿β２－ＭＧ、Ｎ尿ＮＡＧ、尿总蛋白之间的相关很差,没有随工龄增加而降低的趋势。     

职业性镉接触工人尿镉含量的影响因素

目的分析镉接触工人的尿镉含量的影响因素。方法选取无锡某电池厂的镉接触工人437名为接触组,另选取782名未接触镉的工人作为对照组,分析2组人群的尿镉含量水平,同时对此镍镉电池厂进行劳动卫生学调查。结果工作场所中镉及其化合物的短时间接触浓度范围为0．002～3．058mg／m3,超标率为87．5％。接触组尿镉含量（中位数1．4300μmol／mol肌酐）明显高于对照组（中位数0．7300μmol／mol肌酐）,高浓度接触组的尿镉含量（中位数1．7500μmol／mol肌酐）明显高于低浓度接触组（中位数1．2450μmol／mol肌酐）,高浓度接触组的尿镉异常率（6．40％）也明显高于低浓度接触组（2．14％）。对照组和接触组中女性尿镉含量明显高于男性;多元线性回归分析结果显示,车间空气中镉暴露水平、工龄和年龄与尿镉含量的相关系数依次为0．851、0．630和0．038。结论工作场所中镉及其化合物浓度超标、工龄的增加是尿镉含量升高的主要因素,降低工作场所空气中镉及其化合物的浓度至职业接触限值以下和减少接触时间是预防慢性镉中毒的关键。     

石墨炉原子吸收光谱法测定鼠骨中镉的含量研究

镉(Cd)是一种有害的微量元素,由于环境污染而使人或动物接触会使免疫功能受到影响,还会有致癌致畸作用。资料介绍[1],人体血液、心、肝、肾和骨等组织器官都含有镉。其中骨镉的含量为0.1mg/kg(每单位湿重)。镉可以长期或终生蓄积在骨、肾、脑等脏器中。因此,研究骨镉测定方法,进行其含量测定对评价环境和健康效应等都有其重要的意义。本文采用甲酸作溶剂,加压微波消化鼠骨样品,并以氯化钯(PdCl2)作基体改进剂,用石墨炉原子吸收光谱法测定鼠骨中Cd的含量。     

某冶炼厂工人体内镉负荷检测分析

为了解冶炼工人体内金属的负荷水平,检测864名工人及1 101名对照人群的血镉和尿镉含量。采用SPSS 19.0软件对数据进行统计学分析。结果显示,厂区工人血镉中位数(M)和四分位数间距(Q)分别为8.9和17.28μg/L;有67.1%血镉值超过职业接触生物限值5μg/L。对照人群血镉均值和中位数(M)分别为4.7和2.8μg/L。提示,该冶炼厂工人血镉升高由近期职业接触所致。     

镉接触工人尿镉含量水平影响因素分析

目的分析镉接触工人尿镉含量的影响因素。方法选取深圳市3家镍-镉电池厂镉接触工人375名为接触组,另选取153名未接触镉的上岗前工人作为对照组,分析两组人群的尿镉含量水平,同时对3间镍-镉电池厂工作场所进行职业卫生学调查。结果工作场所空气中氧化镉短时间接触浓度平均为0.027 mg/m3,超标率为37.0%;接触组尿镉含量为(3.36±2.43)μmol/molCr,明显高于对照组[(2.09±1.74)μmol/molCr](P<0.01),接触组女性尿镉含量为(3.68±2.92)μmol/molCr,明显高于男性接触组[(2.76±2.21)μmol/molCr](P<0.01);高浓度组尿镉含量[(3.79±3.41)μmol/molCr]明显高于低浓度组[(2.82±2.12)μmol/molCr](P<0.01),高浓度接触组尿镉异常率(21.9%)也高于低浓度接触组(7.7%)(P<0.01);多元线性回归分析结果显示,工龄、工种(接触浓度)、年龄、性别与尿镉含量的相关系数依次为0.559、0.266、0.233和0.092(均P<0.05)。结论工龄增加、工作场所氧化镉浓度超标是尿镉增高的主要危险因素,降低氧化镉浓度至职业接触限值以下和减少接触时间是预防慢性镉中毒的关键。     

职业性镉接触对工人尿β2-微球蛋白的影响

目的了解职业性镉接触工人尿镉和尿β2微球蛋白的关系。方法测定32名镉接触工人的尿镉、尿β2-微球蛋白含量和32名对照组工人的尿β2-微球蛋白含量,对结果进行比较和相关分析。结果与对照组相比,镉接触工人尿β2-微球蛋白排出增加,镉接触工人尿β2-微球蛋白异常率为43.75%,与对照组比较,差异有统计学意义(P<0·05);在镉接触工人中,尿镉正常组尿β2-微球蛋白异常率为33.33%,尿镉增高组尿β2-微球蛋白异常率为52.94%,但2者差异未见有统计学意义。镉接触工人尿镉与尿β2-微球蛋白呈正相关,有统计学意义。结论尿β2-微球蛋白是镉接触工人的早期监测指标,镉接触工人中尿β2-微球蛋白异常率较高,提示我们应重视镉接触工人肾小管损害的健康监护。     

Osteopenia in inhabitants with renal dysfunction induced by exposure to environmental cadmium

Summary Bone density was measured in 28 women with itai-itai disease, 92 men and 114 women with cadmium-induced renal dysfunctions and 44 men and 66 women living in the three different non-polluted areas using a microdensitometer. The values of both indices corresponding to cortical width and bone mineral content were significantly lower in itai-itai disease patients than the cadmium-exposed women with renal dysfunctions and the non-exposed subjects. The cadmium-exposed women also showed a decrease in bone density compared with the non-exposed subjects. A significant decrease in bone density was also observed between cadmium-exposed men and the non-exposed subjects, although the difference was not as clear as in the women. The present study indicates that exposure to cadmium could cause marked osteopenia, particularly in the women.     

Bone mineral measurements among middle-aged and elderly Japanese residents in Hawaii

Cross-sectional data of bone mineral content measured at five skeletal sites (distal radius and ulna, proximal radius and ulna, and os calcis) with single photon absorptiometry were obtained from a population of Japanese-Americans living in Hawaii, comprising 1368 men (aged 61-81 years) and 1098 women (aged 43-80 years). Age-specific mean values of bone mineral content for all skeletal sites were much greater for men than for women and decreased steadily with advancing age in both sexes. The decrease in bone mineral content with age across a 15-year age range was two to four times (depending on skeletal site) greater for women than for men. In multiple regression analyses, age, weight, and postmenopausal estrogen use were potent determinants of bone mineral content for all skeletal sites. Weight was more strongly related to bone mineral content of the os calcis than age in both sexes. Height was significantly related only to the forearm bones. Strenuous exercise was significantly related to bone mineral content of the os calcis and the distal ulna only in men. When compared with US Caucasians of comparable sex and age, the Japanese in Hawaii have lower bone mineral content of the radius. This may partly be explained by the difference in body size. Significant correlations were found between bone mineral content of appendicular bones and radiographically determined vertebral osteoporosis.     

Changes in bone mineral density 10 years after marked reduction of cadmium exposure in a Chinese population

The main focus of this study was to evaluate the long-term effects of Cd on forearm bone mineral density after the cessation of the ingestion of Cd-polluted rice. A total of 458 persons (294 women, 164 men) from three Cd exposure areas (low, moderately, and heavy) participated in this study. Those living in the moderate and heavy exposure areas ceased ingesting Cd-polluted rice (0.51 and 3.7 mg/kg, respectively) in 1996 (10 years prior to present analysis). The participants completed a questionnaire and bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at the proximal radius and ulna. The changes and change percentage in forearm bone density and the prevalence of osteoporosis between 1998 and 2006 were used as markers of bone recovery. The Cd concentrations in urine (UCd) and blood (BCd) in 1998 were used as Cd exposure markers. The values of the BMD change and change percentage of groups in which UCd was above 5 μg/g creatinine (μg/g crea) and BCd was above 10 μg/L were significantly higher than those of the low-exposure groups (in women, p<0.001; in men, p>0.05). The BMD change and change percentage correlated positively with the UCd and BCd (in women, p<0.01; in men, p>0.05). Analysis of the Z-score revealed that the prevalence of osteoporosis in 2006 was higher than that in 1998 and increased along with the level of UCd and BCd in both women and men, especially for those subjects with the higher BCd [BCd>5 μg/L, OR=3.45 (0.95-13.6); BCd>10 μg/L, OR=4.51(1.57-13.54)] and UCd [UCd>10 μg/g crea, OR=4.74 (1.82-12.81)] in women. It is concluded that decreasing dietary cadmium exposure at the population level is not associated with bone recovery at the individual level, and the adverse bone effects of Cd exposure persisted after the main source of Cd exposure had been blocked, especially in women.     

Calcium supplementation and bone loss in middle-aged women

This 4-y study investigated the effects of a calcium carbonate supplement on bone loss in 169 women aged 35-65 y, randomly assigned to placebo and treatment (1500 mg Ca/d) groups in a double-blind design. Bone mineral content (BMC) and width (W) were measured bilaterally on the radius, ulna, and humerus. BMC and BMC/W loss rates were consistently lower in treatment than in control subjects. Loss was significantly reduced in the left and right humerus and the right radius. In premenopausal subjects, only left humerus BMC loss was significantly reduced by Ca supplementation. In postmenopausal treatment subjects, BMC and BMC/W bone loss was reduced in all 12 (bilateral radius, ulna, and humerus) of the bone variables measured, 5 at p less than 0.01 and 2 at p less than 0.05. Ca supplementation counteracted a large portion of the additional bone loss attributable to menopause in this population.     

Sex steroids, bone turnover and bone mineral density in pre-, peri-, and postmenopausal women

To examine 1) the relationships between endogenous androgens and bone mineral density (BMD), 2) the relationships between sex-hormone binding globulin (SHBG) and BMD, and 3) the associations of endogenous androgens and SHBG with biochemical markers of bone turnover, a cross-sectional study was carried out in 88 healthy pre-, peri-, and postmenopausal women aged 35 to 74. Measurements of BMD_s at the ultradistal radius and ulna, and the distal radius (using DEXA), estrogens, androgens, deoxypyridinoline (D-Pyr) and intact bone gla protein (I-BGP) were performed. In the multivariate regression models testosterone (T) was positively correlated with BMD at the ultradistal radius and ulna in perimenopausal women, and was positively correlated with BMD at the ultradistal radius and ulna, and the distal radius in postmenopausal women. T was positively associated with I-BGP in premenopausal women (r = 0.65, p < 0.01), and negatively associated with D-Pyr in pre- (r = -0.53, p < 0.05) and postmenopausal women (r = -0.49, p < 0.001). On the other hand, SHBG was negatively correlated with BMD at die ultradistal radius and ulna, and die distal radius in pre- and postmenopausal women in the models. SHBG was positively related to D-Pyr in pre(r = 0.57, p < 0.05) and postmenopausal women (r = 0.41, p < 0.01), and negatively related to I-BGP in postmenopausal women (r = -0.38, p < 0.01). These findings suggest that endogenous androgens may exert positive influences on BMD, and that SHBG may have negative effects on BMD.     

长期饮用学生奶与儿童骨密度的关系

目的了解长期饮用学生奶对儿童骨密度的影响。方法于2009年7月份,在湖南省长沙市整群抽取435名10～12岁学生(其中男生188名,女生247名),调查学生奶饮用情况,根据学生饮奶频率和连续饮奶的时间,将被调查的学生分为长期饮奶组(连续1年以上和坚持每周饮奶4次以上或连续3年以上每周饮奶1～3次者为长期饮奶组,220人)和较少饮奶组,测定其右前臂长度、桡尺骨远端1/3处骨宽度(BW)、骨矿物质含量(BMC)和骨密度(BMD)、血磷和钙含量。结果长期饮奶组男孩右前臂长(22.53cm±1.63cm vs.21.95cm±1.75cm,P<0.05)、桡骨BW(1.370cm±0.237cm vs.1.300cm±0.176cm,P<0.05)、桡骨BMC(0.690±0.270 vs.0.599±0.090,P<0.01)、桡骨BMD(0.498±0.135 vs.0.462±0.055,P<0.05);女孩桡骨BMD(0.489±0.076 vs.0.469±0.081,P<0.05)、尺骨BMC(0.564±0.176 vs.0.512±0.100,P<0.01、尺骨BMD(0.470±0.129 vs.0.439±0.059,P<0.05均明显高于较少饮奶组。儿童饮用学生奶与奶制品的种类和性状密切相关。结论长期饮用学生奶可增加儿童骨密度,奶制品的种类及性状影响学生奶计划的实施与推广。     

Metallothionein in cadmium-exposed workers

A radioimmunoassay for human metallothionein (Mt) was utilized to measure urinary Mt in cadmium-exposed and nonexposed workers. Workers in an environment of high concentration had higher Mt levels than those in an environment of lower Cd concentration. Control groups had lower Mt levels than either exposed group. Additional urinary proteins were measured in order to assess functional renal status. Mt concentration in urine was similar in individuals with and without renal damage. Mt concentration in urine was found to correlate with urinary Cd level, a correlation (r) of 0.94 being obtained between log Cd in urine and log Mt in urine. Additionally, a correlation of 0.82 was obtained between log Cd in blood and log Mt in urine.     

An improved instrument for the in vivo detection of lead in bone.

An improved instrument for the fluorescence excitation measurement of concentrations of lead in bone has been developed. This is based on a large area high purity germanium detector and a point source of 109Cd. The source is positioned in a tungsten shield at the centre of the detector face such that 88keV photons cannot enter the detector directly. In vivo measurements are calibrated with plaster of Paris phantoms. Occupationally non-exposed men show a minimum detectable concentration of about 6 micrograms/g bone mineral. Measurements of tibia lead concentrations in 30 non-occupationally exposed men between the ages of 23 and 73 showed an annual increment of 0.46 microgram/g bone mineral/year. The mean deviation from the regression of tibia lead upon age was 3.5 micrograms/g bone mineral. Tibia lead concentration in one subject with a history of exposure to lead was 69.6 (SD 3.5) micrograms/g bone mineral. The improved precision of the point source large detector system means that greater confidence can be placed on the results of in vivo measurements of lead concentration. This will allow studies of the natural history of non-occupational lead accumulation in normal subjects and should permit investigations of the efficacy of therapeutic interventions in subjects poisoned with lead.     

沈阳市镉污染区居民尿镉及骨密度调查

目的通过检测脱离环境镉接触人群的尿镉及骨密度，探讨镉致肾损伤的远期效应与骨密度的关系。方法选择在镉污染区连续居住20年以上的居民为调查对象，应用GMY-1型单光子骨密度吸收仪，测量其桡骨远端骨密度（BMD）；用原子吸收分光光度法检测该人群的尿镉（UCd）水平。结果污染区居民的尿镉水平显著高于对照组（P〈0．05），并随着镉污染程度的增加而增高；BMD随着UCd水平的增加而下降，接触组与对照组差异有统计学意义（P〈0．05）。结论长期脱离镉污染环境后，体内镉仍处于一个较高水平，并影响骨代谢导致骨密度下降。