人类NRAMP1基因单核苷酸多态与接尘工人肺结核易感性

目的 探讨人类自然抵抗相关巨噬细胞蛋白1（NRAMP1）基因多态性与接尘工人肺结核易感性的关系.方法 采用1：2病例对照设计,按年龄相差小于5岁,工种、吸烟、饮酒率、总粉尘接触量和矽肺患病同比例匹配,选择61例男性肺结核患者为病例组（矽肺50例、非矽肺11例）,122例男性无肺结核者为对照组（矽肺100例、非矽肺22例）.应用聚合酶链反应-限制性片段长度多态性分析（PCR-RFLP）技术检测NRAMP1 INT4和D543N位点的多态性.结果 NRAMP1 INT4多态位点野生纯合子（G/G）、杂合子（G/C）和突变纯合子（C/C）在病例组的分布频率分别为63.9%、34.4%、1.6%,与对照组比较,差异有统计学意义（P＜0.05）,NRAMP1 INT4 C等位基因携带者患肺结核的危险性升高（OR=2.73,95% CI：1.32～5.64）,D543N位点多态与接尘工人肺结核易感性之间无关联（P＞0.05）.结论 NRAMP1基因第4内含子G＞C单核苷酸可能是接尘工人肺结核的易感因素.     

Risk of pulmonary tuberculosis relative to silicosis and exposure to silica dust in South African gold miners [published erratum appears in Occup Environ Med 1999 Mar;56(3):215-6]

OBJECTIVES: To investigate the following questions. (1) Is silica dust on its own, without the presence of silicosis, associated with an increased risk of pulmonary tuberculosis (PTB) in workers exposed to silica dust? (2) In the absence of silicosis is the excess risk dose related? (3) What is the predominant chronological sequence between the development of PTB and the development of silicosis after the end of exposure to dust? METHODS: A cohort of 2255 white South African gold miners has been followed up from 1968 to 1971, when they were 45-55 years of age, to 31 December 1995 for the incidence of PTB. During the follow up 1592 (71%) men died. Of these, 1296 (81%) had a necropsy done at the National Centre for Occupational Health (NCOH) to determine the presence of silicosis and PTB. The incidence of PTB in the cohort was studied relative to cumulative exposure to dust and the onset of silicosis. For the miners with necropsy, the incidence for PTB was studied relative to the severity of silicosis found at necropsy. RESULTS: There were 115 subjects who developed PTB. The total person- years of follow up was 39,319. For the whole cohort, the factors associated with increased risk of PTB were cumulative exposure to dust (mg/m3.y) (the adjusted rate ratio (RR) 1.07; (95% confidence interval (95% CI) 1.04 to 1.10)), silicosis diagnosed radiologically (3.96 (2.59 to 6.06)), and tobacco pack-years (1.02 (1.01 to 1.03)). The RR (95% CI) for PTB increased with increasing quartiles of cumulative exposure to dust 1.0, 1.51 (0.78 to 2.91), 2.35 (1.28 to 4.32), and 3.22 (1.75 to 5.90). In miners who did not have radiologically diagnosed silicosis (n = 1934, PTB = 74), the adjusted RR (95% CI) for PTB and cumulative exposure to dust was 1.10 (1.06 to 1.13), and increased with quartiles of cumulative exposure to dust as 1.00, 1.46 (0.70 to 3.03), 2.67 (1.37 to 5.23), and 4.01 (2.04 to 7.88). For the subjects who had a necropsy (n = 1296, PTB = 70), the adjusted RR (95% CI) for PTB increased with the severity of silicosis found at necropsy; 1.0 for no silicosis, 1.88 (0.97 to 3.64) for negligible, 2.69 (1.35 to 5.37) for slight, and 2.30 (1.16 to 4.58) for moderate or marked silicosis. For subjects who had a necropsy and no silicosis (n = 577, PTB = 18), the adjusted RR (95% CI) increased slightly with quartiles of cumulative dust 1.0, 1.11 (0.31 to 4.00), 1.42 (0.43 to 4.72), and 1.38 (0.33 to 5.62). CONCLUSION: Exposure to silica dust is a risk factor for the development of PTB in the absence of silicosis, even after exposure to silica dust ends. The risk of PTB increases with the presence of silicosis, and in miners without radiological silicosis, with quartiles of exposure to dust. The severity of silicosis diagnosed at necropsy was associated with increasing risk of PTB and even < 5 nodules--that is, undetectable radiologically--was associated with an increased risk of PTB. The diagnosis of PTB was on average 7.6 years after the end of exposure to dust, at around 60 years of age. The onset of radiological silicosis preceded the diagnosis of PTB in 90.2% of the cases with PTB who had silicosis. The results have implications for medical surveillance of workers exposed to silica dust after the end of exposure.       

自然抗性相关巨噬细胞蛋白1基因多态性与肺结核易感性的研究

目的　探讨自然抗性相关巨噬细胞蛋白 1基因 (NRAMP1)多态性与中国汉族人群肺结核发病的关系。方法　采用以医院为基础的病例对照研究设计 ,用聚合酶链反应 限制性片段长度多态性分析 (PCR RFLP)法检测NRAMP1基因中INT4、D5 4 3N及 3′UTR 3个多态性位点的基因型 ,并对结核病相关危险因素进行问卷调查 ,应用SPSS软件进行单因素和多因素非条件logistic回归分析。2 0 0 1年 4月至 2 0 0 2年 6月选择 110例肺结核病例 ,平均年龄为 (2 8± 13)岁 ;对照组为 180名健康体检者 ,平均年龄为 (2 7± 9)岁。对NRAMP1基因各多态性位点进行单因素分析。结果　病例组D5 4 3NG/A及 3′UTRTGTG +/del基因型频率显著高于对照组 ,OR值 (95 %CI)分别为 2 2 2 (1 0 3～ 4 78)和 1 93(1 14～ 3 2 6 )。病例组和对照INT4各基因型频率比较差异无显著性。多因素分析调整暴露史和疫苗接种史 2个因素后 ,D5 4 3NG/A及 3′UTRTGTG +/del基因型仍与结核病显著相关 ,调整OR值 (95 %CI)分别为 3 0 4 (1 12～ 8 2 7)和 2 36 (1 2 0～ 4 6 4 ) ,而病例和对照组INT4位点多态性比较差异未见显著性。结论　NRAMP1基因D5 4 3N及 3′UTR位点多态性可能是汉族人群肺结核的易感因素。     

肿瘤坏死因子-a及其Ⅱ型受体基因多态性与矽肺

目的探讨肿瘤坏死因子-a(TNF-a)及其Ⅱ型受体(TNFRⅡ)基因多态性在矽肺发病遗传易感性中的作用及其与二氧化硅暴露的交互作用.方法选择259例矽肺患者和341例矽尘接触者(对照)为研究对象,对其职业史、尘肺病史、既往病史等进行问卷调查;拍摄其高仟伏X射线后前位胸片,根据尘肺病诊断标准进行诊断和分期;采集每个研究对象的外周静脉血,应用聚合酶链反应-限制性片断长度多态性(PCR-RFLP)技术检测其TNF-a及TNFRⅡ基因多态性.结果在成组或11配对分析中,矽肺患者和矽尘接触者两组间TNF-a基因-308位点G/A+A/A基因型和TNFRⅡ196位点T/G+G/G基因型分布频率的差异均无统计学意义(P＞0.05).当接尘工龄＜15年时,G/A+A/A基因型携带者发生矽肺的危险性是G/G基因型的6.74倍,95%CI1.01～44.99.结论TNF-α和TNFRⅡ基因多态性在汉族人群矽肺发病的遗传易感性中不起主要作用.TNF-α基因-308位点基因多态性在矽肺发病过程中与接尘工龄存在交互作用,当累积接尘量较低时,G/A+A/A基因型携带者发生矽肺的危险性较G/G基因型明显增加.     

Lack of association between cytokine gene polymorphisms and silicosis and pulmonary tuberculosis in Chinese iron miners

Silicosis is a fibrotic lung disease produced by the inhalation and deposition of silica dust. The association between silicosis and pulmonary tuberculosis (PTB) has been well established. Cytokines participate in the development and progression of silicosis and PTB. Functional polymorphisms in cytokine genes have been identified that alter cytokine production. The aims of the current investigation were to determine whether functional polymorphisms in the tumor necrosis factor-alpha (TNF-alpha) gene at position -308; in the transforming growth factor-beta 1 (TGF-beta1) gene at positions -509, +869 (codon 10), and +915 (codon 25); in the interleukin-10 (IL-10) gene at position -1,082, -819 and -592; and in the intron 1 of the interferon-gamma (IFN-gamma) gene at position +874 are associated with silicosis and PTB. We conducted a case-control study with 183 silicosis patients and 111 silica-exposed miners, and a 1:2 matched case-control study of 61 PTB cases and 122 PTB-free miners. Genotype analysis was performed on genomic DNA, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. There was complete linkage disequilibrium (LD) between the -819C and -592C alleles of the IL-10 gene. The genotype frequencies were similar between cases and control subjects for all investigated cytokine polymorphisms (p>0.05). We did not find an association between the different genotypes and severity of silicosis. We assume that these genetic variants do not play a dominant role in silicosis and PTB in our Chinese population.     

Tuberculosis and silica exposure in South African gold miners

Aims

To examine the effect of silica exposure, in the absence of silicosis, on the prevalence of pulmonary tuberculosis (PTB), which is epidemic among South African gold miners.

Methods

Cross‐sectional study of 520 gold miners over 37 years of age. Length of service, and cumulative and average dust and quartz exposure indices were derived for each miner. Chest radiographs were read for PTB by two NIOSH “B” readers. PTB was defined as a self‐reported history of PTB or PTB on chest radiograph. Logistic regression was used to adjust for age, smoking, and silicosis. PTB effects of different exposure metrics for silica, scaled on their interquartile range (IQR), were compared.

Results

Means (ranges) were: age 46.7 (37.1–59.9) years; length of service 21.8 (6.3–34.5) years; average intensity of respirable quartz 0.053 (0–0.095) mg/m³. PTB prevalence was 19.4% (95% CI 16.0 to 22.8) on history alone, and 35.2% (95% CI 31.1 to 39.3) on history or on chest radiograph. Length of service was poorly predictive of PTB, while all exposure indices which included dust or quartz yielded prevalence odds ratios (PORs) of approximately 1.4 (95% CI ∼1.1 to 1.8) for changes of one interquartile range in exposure. Controlling for silicosis—by adjustment or restriction—did not modify these results. Drillers and winch operators had the highest PTB prevalences and the highest dust and silica exposures.

Conclusion

Older in‐service gold miners in South Africa have a high prevalence of PTB, which is significantly associated with dust and silica exposure, even in the absence of silicosis. Limitations include a survivor workforce and the use of cumulative exposures based on current exposures. Dust control is an important component in control of the PTB epidemic in South African gold mines.     

东亚人群NRAMP1基因多态性与结核易感性的Meta分析

目的应用Meta分析探讨东亚人群NRAMP1基因3个多态性位点与结核易感性的关系。方法应用主题词和关键词“NRAMP1”、“SLC11A1”、“tuberculosis”和“结核”,检索1995年1月至2005年5月Medline、Ovid及CBMdisc数据库发表的有关文献,并辅以文献追溯的方法。结果结核病组和对照组3’UTR、D543N和INT4位点的多态现象同最常见纯合子基因型频率比值比（OR）的合并OR值分别为1．68（95％CI：1．31～2．16,P〈0．001）;178（95％CI：1,38～2．30,P〈0．001）;1．56（95％CI：0．72～3．35,P=0．26）。Egger线性回归分析提示3’UTR和D543N基因型相关文献没有发表偏倚,INT4基因型相关文献有一定的出版偏倚。结论东亚人群NRAMPl基因3’UTR和D543N多态性位点与结核易感性相关;INT4多态性位点与结核易感性无统计学意义。     

NRAMP1基因INT4和3’UTR位点多态性与肺结核易感性的研究

目的 探讨人类自然抵抗相关巨噬细胞蛋白1（NRAMP1）基因INT4和3＇UTR位点多态性与中国北方汉族成人肺结核发病的关系.方法 采用1：1配对的病例对照研究设计,用聚合酶链反应-限制性片段长度多态性分析方法检测NRAMP1基因中INT4和3＇UTR两个多态性位点,对与肺结核相关的危险因素进行问卷调查,进行单因素和多因素条件logistic回归分析,同时对基因型与肺结核病变的性质和程度进行研究.结果 对124对研究对象进行了INT4和3＇UTR两个多态性位点的基因分型,3＇UTR TGTG＋/del基因型病例组频率显著高于对照组,粗OR值（95%CI）为2.923（1.557～5.487）.病例组和对照组INT4各基因型频率比较差异均无统计学意义.对17个环境危险因素进行了单因素分析,在多因素分析中调整卡痕、体重指数、人均居住面积、家族史4个因素后,3＇UTR TGTG＋/del基因型仍与肺结核显著相关,调整OR值（95%CI）为2.955（1.369～6.381）.在INT4不同基因型中,病例组和对照组肺结核病变性质差异具有统计学意义（x2=9.634,P＜0.05）.结论 NRAMP1基因3＇UTR位点多态性可能是中国北方汉族成人肺结核的易感因素,而INT4多态性可能与肺结核的病变性质有关系.     

Risk of silicosis in cohorts of Chinese tin and tungsten miners, and pottery workers (I): an epidemiological study

BACKGROUND: Epidemiological evaluations of the risk of silicosis in relation to exposure to crystalline silica have raised the question of whether different types of silica dust exposures vary with respect to their ability to cause silicosis. The aim of this study is to compare the risk of silicosis among cohorts of silica dust-exposed Chinese tin miners, tungsten miners, and pottery workers and to assess whether gravimetric measurements of respirable silica dust sufficiently determine the risk of silicosis or whether other factors of exposure may play a significant role. METHODS: Cohorts were selected from 20 Chinese mines and potteries. Inclusion criteria were starting employment after January 1, 1950 and being employed for at least 1 year during 1960-1974 in one of the selected workplaces. Radiological follow-up for silicosis onset was from January 1, 1950 through December 31, 1994. Silicosis was assessed according to the Chinese radiological criteria for diagnosis of pneumoconiosis (as suspect, Stage I, II, or III). Exposure-response relationships were estimated for silicosis of Stage I or higher. Silica dust exposure was estimated in terms of cumulative total dust exposure, calculated from a workplace, job title, and calendar year exposure matrix, and individual occupational histories. Cumulative total dust exposure was converted in two steps into cumulative respirable dust exposure and cumulative respirable silica dust exposure using conversion factors estimated from side-by-side measurements conducted in 1988-89. RESULTS: The male cohorts included 4,028 tin miners, 14,427 tungsten miners, and 4,547 pottery workers who had similar onset of employment and duration of follow-up. For a given exposure level, the risk of silicosis was higher for the tin and tungsten than the pottery workers. CONCLUSION: The observed differences in the risk of silicosis among the three cohorts suggest that silica dust characteristics, in addition to cumulative respirable silica dust exposure, may affect the risk of silicosis.     

广西锡矿矿尘致矽肺的危险度评价

目的　探索锡矿矿尘的致病强度和最低无害作用水平。方法　选择广西锡矿 1 960～1 974年期间接触矿尘至少 1年的男性矿工 4 471名建立回顾性接尘队列 ,并用以同一方法建立的瓷厂接尘队列与其进行比较 ;采用SAS中的生存检验分析软件进行非参数估算 ,评价锡矿矿尘致矽肺的危险度。结果　随访到 1 994年底 ,锡矿队列工人矽肺发病 971例 (2 1 .7% ) ,其中 81 %的病例为 1 958年前接尘对象 ,累积接触总粉尘量 (CTD)与矽肺危险度明显相关 :当CTD <50mg·m- 3·年 - 1 时 ,矽肺危险度为 0 .0 1 2 ;CTD >40 0mg·m- 3·年 - 1 时 ,矽肺危险度上升到 0 .971。瓷厂接尘工人CTD >40 0mg·m- 3·年 - 1 时 ,矽肺危险度仅为 0 .369。结论　锡矿接触矿尘工人的矽肺发病与CTD明显相关 ;锡矿矿尘导致矽肺的危险性远比瓷厂的陶瓷尘严重     

NRAMP1 D543N and INT4 polymorphisms in susceptibility to pulmonary tuberculosis: A meta-analysis

The association of natural resistance associated macrophage protein 1 (NRAMP1) polymorphisms (D543N, INT4) with pulmonary tuberculosis (PTB) risk have been widely reported. However, the findings of previous studies were inconsistent. To clarify the role of these polymorphisms in PTB, we performed a meta-analysis of all available and relevant published studies. Based on comprehensive searches of the PubMed, Medline, Embase, Web of Science, Elsevier Science Direct and Cochrane Library database, we identified outcome data from all articles estimating the association between NRAMP1 polymorphisms and PTB risk. For D543NA/G polymorphism, no associations were found in all genetic models. For INT4C/G polymorphism, significant increased PTB risk was observed in recessive model (CC vs. GC + GG: P = 0.025, OR = 1.35, 95% CI = 1.04–1.75). In the subgroup analysis by ethnicity, significantly increased risk were observed for D543NA/G polymorphism in Americans (GA vs. GG: P = 0.03, OR = 1.31, 95% CI = 1.03–1.67; AA + AG vs. GG: P = 0.032, OR = 1.29, 95% CI = 1.02–1.63). Moreover, the INT4C/G polymorphism was also associated with increased risk of TB for Africans in allele model (A vs. G: P = 0.012, OR = 1.41, 95% CI = 1.08–1.85), heterozygous model (GA vs. GG: P = 0.004, OR = 1.53, 95% CI = 1.14–2.04) and dominant model (AA + AG vs. GG: P = 0.007, OR = 1.49, 95% CI = 1.12–1.98). This meta-analysis provides evidences that INT4C/G was associated with increased susceptibility to pulmonary tuberculosis in overall population in recessive model. D543NA/G polymorphism was associated with PTB increased risk in Americans, while INT4C/G polymorphism in Africans. Further well-designed, large scale studies are required to confirm this conclusion.     

锡矿工人接尘与矽肺危险度评价

目的探讨粉尘暴露与矽肺危险度之间的接触效应关系。方法选择广西４个锡矿１９６０～１９６５年间工作１年以上的３０１０名接尘工人进行队列研究。用生存分析法统计累积粉尘接触量和矽肺出现的关系。结果追访到１９９４年底,检出矽肺１０１５例（３３．７％）。矽肺平均潜伏期２１．３年。总粉尘浓度７．５ｍｇ／ｍ３（ＴＷＡ）。拟合生存分析模型表明：矽肺发病危险度与累积接尘量的关系适合Ｗｅｉｂｕｌ分布。累积总粉尘接触量低于１０ｍｇ·ｍ－３·ａ－１时,矽肺危险小于１％;累积总粉尘接触量超过２０ｍｇ·ｍ－３·ａ－１时,矽肺累积危险度升高加快;累积总粉尘接触量达１５０ｍｇ·ｍ－３·ａ－１时,矽肺危险超过６８％。接尘时间与接尘量和矽肺危险度呈正相关。结论矽肺危险度与累积接尘量之间存在接触效应关系。     

Exposure to silica and silicosis among tin miners in China: exposure-response analyses and risk assessment

OBJECTIVES—To investigate the risk of silicosis among tin miners and to investigate the relation between silicosis and cumulative exposure to dust (Chinese total dust and respirable crystalline silica dust).
METHODS—A cohort study of 3010 miners exposed to silica dust and employed for at least 1 year during 1960-5 in any of four Chinese tin mines was conducted. Historical total dust data from China were used to create a job exposure matrix for facility, job title, and calendar year. The total dust exposure data from China were converted to estimates of exposure to respirable crystalline silica for comparison with findings from other epidemiological studies of silicosis. Each worker''s work history was abstracted from the complete employment records in mine files. Diagnoses of silicosis were based on 1986 Chinese pneumoconiosis Roentgen diagnostic criteria, which classified silicosis as stages I-III—similar to an International Labour Organisation (ILO) classification of 1/1 or greater.
RESULTS—There were 1015 (33.7%) miners identified with silicosis, who had a mean age of 48.3 years, with a mean of 21.3 years after first exposure (equivalent to 11.0 net years in a dusty job). Among those who had silicosis, 684 miners (67.4%) developed silicosis after exposure ended (a mean of 3.7 years after). The risk of silicosis was strongly related to cumulative exposure to silica dust and was well fitted by the Weibull distribution, with the risk of silicosis less than 0.1% when the Chinese measure of cumulative exposure to total dust (CTD) was under 10 mg/m³-years (or 0.36 mg/m³-years of respirable crystalline silica), increasing to 68.7% when CTD exposure was 150 mg/m³-years (or 5.4 mg/m³-years of respirable crystalline silica). Latency period was not correlated to the risk of silicosis or cumulative dose of exposure. This study predicts about a 36% cumulative risk of silicosis for a 45 year lifetime exposure to these tin mine dusts at the CTD exposure standard of 2 mg/m³, and a 55% risk at 45 years exposure to the current United States Occupational Safety and Health Administration and Mine Safety and Health Administration standards of 0.1 mg/m³ 100% respirable crystalline silica dust.
CONCLUSIONS—A clear exposure-response relation was detected for silicosis in Chinese tin miners. The study results were similar to most, but not all, findings from other large scale exposure-response studies.


     

Association between lymph node silicosis and lung silicosis in 4,384 German uranium miners with lung cancer

This study investigates the association between lymph node-only and lung silicosis in uranium miners with lung cancer and exposure to quartz dust. Tissue slides of 4,384 German uranium miners with lung cancer were retrieved from an autopsy archive and reviewed by 3 pathologists regarding silicosis in the lungs and lymph nodes. Cumulative exposure to quartz dust was assessed with a quantitative job-exposure matrix. The occurrence of silicosis by site was investigated with regression models for exposure to quartz dust. Miners with lung silicosis had highest cumulative quartz exposure, followed by lymph node-only silicosis and no silicosis. At a cumulative quartz exposure of 40 mg/m(3) × years, the probability of lung silicosis was above 90% and the likelihood of lymph node-only silicosis and no silicosis do not differ anymore. The results support that lymph node silicosis can precede lung silicosis, at least in a proportion of subjects developing silicosis, and that lung silicosis strongly depends on the cumulative quartz dose.     

NRAMP1基因和人类对结核分枝杆菌的易感性

NRAMP1基因,又称SLC11A1基因,位于2号染色体长臂35区(2q35),包括15个外显子及内含子4中交替出现的1个外显子,长13 604 bp.NRAMP1的常见多态性基因有D543N、3′UTR、INT4和5′(GT)n等,和结核易感性相关.NRAMP1蛋白由巨噬细胞表达,是一种H+/二价阳离子的反向转运体,对巨噬细胞的功能有多效性.此文对NRAMP1基因及其和MTB的易感相关性的研究结果进行综述.     

铁矿工肺癌病因病例对照研究

本研究系在历史前瞻性队列研究基础上,采用同厂矿队列内病例:对照=1:4配比,对接尘、矽肺、吸烟与肺癌之间关系进行了对比分析。结果未发现肺癌发病与接尘、矽肺有直接关系;但结果说明吸烟与肺癌关系密切。     

吸烟与矽肺：某矿区的定群研究

通过对1077名井下矿工队列的28年回顾性定群研究,发现吸烟组矽肺发病率为13.02%,非吸烟组为6.85%。吸烟组矽肺的标化发病率比为171.43(95%CI=144.69～203.97)。以接尘工龄作时间变量,用Weibull回归模型分析累积接尘量和吸烟对矽肺的影响。结果表明在平衡了接尘工龄后,累积接尘量和吸烟对矽肺发病的影响有显著性意义,说明了有吸烟习惯的接尘工人发生矽肺的危险度比不吸烟者大。因此,在预防矽肺的措施上,应强调控制吸烟的重要性。     

FAS和FASL基因多态性与矽肺易感性的关系

目的 探讨FAS和FASL基因多态性与矿工矽肺遗传易感性的关系.方法 采用病例对照设计,以183例男性矽肺患者为病例组,111例无矽肺的男性接尘矿工为对照组,调查研究对象的一般情况及职业史,收集现场粉尘浓度资料,估算工人既往累积总粉尘接触量;应用聚合酶链反应一限制性片段长度多态性分析(PCR-RFLP)技术检测FAS-1377、FAS-670及FASL-844位点的多态性,分析多态性与矽肺患病及矽肺期别的关系,基因间以及基因与环境因素间的交互作用以及单倍型.结果 FAS-1377、FAS-670及FASL-844各位点基因型在病例组和对照组间的分布差异均无统计学意义(P》0.05);不同期别矽肺患者中FAS-1377、FAS-670及FASL-844位点多态分布差异无统计学意义(P》0.05);病例组中FAS-1377G/-670G单倍型分布频率为9.6%,明显高于对照组(3.6%),差异有统计学意义(P《0.05);各基因多态间、基因多态与累积总粉尘接触量以及基因多态与吸烟状况之间的交互作用分析结果均无统计学意义(P》0.05).结论 FAS-1377、FAS-670及FASL-844多态性在矽肺发病的遗传易感性中不起主要作用.单倍型FAS-1377G/-670G可能是矽肺发生的易感性标记.     

Risk of silicosis in a cohort of white South African gold miners

The risk of silicosis was investigated in a cohort of 2,235 white South African gold miners who had, on average, 24 years of net service from 1940 to the early 1970s and who were followed up to 1991 for radiological signs of onset of silicosis (ILO category 1/1 or more). There were 313 (14%) miners who developed signs of silicosis at an average age of 55.9 years. The latency period was largely independent of the cumulative dust exposure. In 57% of the silicotics, the radiological signs developed, on average, 7.4 years after mining exposure ceased. The risk of silicosis increased exponentially with the cumulative dust dose, the accelerated increase being after 7 mg/m³-years. At the highest exposure level of 15 mg/m³-years, which represents approximately 37 years of gold mining at an average respirable dust concentration of 0.4 mg/m³, the cumulative risk for silicosis reached 77%. In conclusion, the risk of silicosis was strongly dose dependent; however, the latency period was largely independent of the dose. © 1993 Wiley-Liss, Inc.