Effects of occupational metallic mercury vapour exposure on suppressor-inducer (CD4+CD45RA+) T lymphocytes and CD57+CD16+ natural killer cells

Objectives: To examine the effects of metallic mercury vapour on the cellular and humoral immune system. Methods: We measured T lymphocyte and natural killer (NK) cell subpopulations, B lymphocytes, and serum immunoglobulins (i.e. IgG, IgA and IgM) together with total T (CD3+) lymphocytes and total lymphocytes in blood samples from 20 male, fluorescent-lamp makers (mercury workers) and the same number of gender-, age- and smoking-matched controls. Urinary concentrations of inorganic mercury (UHg) in the 20 workers ranged from 1.8 to 163.5 (mean 44.8) μg/l. They had been exposed to mercury vapour for 4 to 62 (mean 31) months. Results: Numbers of CD4+CD45RA+ (suppressor-inducer) T lymphocytes and total CD4+ T lymphocytes in the mercury workers were significantly smaller than those in the controls (paired-sample t-test, P < 0.01). The number of CD57+CD16+ NK cells was inversely correlated with UHg. Conclusion: It is suggested that numbers of CD4+CD45RA+ T lymphocytes and CD57+CD16+ NK cells are inversely affected by exposure to metallic mercury vapour in workers, with an average urinary inorganic mercury concentration of 45 μg/l being found. Received: 7 September 1999 / Accepted: 6 May 2000     

Changes in natural killer cell subpopulations in lead workers

To investigate the effects of lead on human immune system, we analyzed T cell subpopulations (CD4+, CD8+ and CD3+ cells), natural killer (NK) cell subpopulations (CD16+ and CD57+ cells) and B (CD19+) cells in peripheral blood in 29 male lead workers. All were engaged in manufacturing lead stearate in a chemical factory. They were aged 23–74 (mean 49) years. Their blood lead concentrations (PbB) were between 7 and 35 (mean 18) μg/dl. They were divided into two groups according to their PbB: a high-PbB group (?20?μg/dl), and a low-PbB group (<20?μg/dl). The control group consisted of 19 “healthy” male workers without a history of occupational exposure to lead or to other hazardous substances, aged 48–67 (mean 58) years. The number and percentage of CD16+ cells in the high-PbB group were significantly lower than those in the controls and in the low-PbB group. There was significant negative correlation between the number of CD16+ cells and PbB in the lead workers. The percentage of CD8+ cells in the high-PbB group was larger than that in the controls and in the low-PbB group. It is suggested that the CD16+ NK cell should be a major site of the effects of lead on lymphocyte subpopulations.     

Decreases of CD4- and CD8-positive T lymphocytes in retired chromate workers

To investigate the effects of chromates on the human immune system, we measured total T lymphocytes and their two major subpopulations (CD4 + and CD8 + T lymphocytes) in the peripheral blood of 19 retired male workers who had been exposed to chromate at a chemical plant. The results indicated that both CD4 + and CD8 + T lymphocytes were significantly decreased, resulting in decreases in total T lymphocytes and total lymphocytes.     

原因不明复发性流产与CD56CD16NK细胞的相关性研究

目的:探讨原因不明复发性流产(URSA)与外周血和蜕膜组织中CD56+CD16-、CD56+CD16+NK细胞水平及CD56+CD16-/CD56+CD16+平衡的相关性。方法:选取30例早孕原因不明复发流产患者为试验组,20例正常早孕人流妇女为对照组,采集两组病例的蜕膜组织及外周血标本,分离淋巴细胞,用流式细胞技术检测各组标本中CD56+CD16-、CD56+CD16-NK细胞的数量,计算ED56+ED16-/CD56+ED16+平衡偏移。结果:两组外周血中CD56+CD16-细胞和CD56+CD16+NK细胞水平以及CD56+CD16-/CD56+CD16+比值差异均无统计学意义(P>0.05);两组蜕膜组织中,URSA组CD56+CD16+NK细胞水平升高,ED56+CD16-/ED56+CD16+比值降低,差异均有统计学意义(P<0.05),CD56+CD16-细胞与对照组比较差异无统计学意义(P>0.05);对照组蜕膜组织中CD56+CD16-NK细胞数及CD56+CD16-/CD56+CD16+比值均高于其外周血相应值,差异有统计学意义(P<0.05),CD56+CD16+NK细胞数在两组间差异无统计学意义(P>0.05);在URSA组中,蜕膜组织中的CD56+CD16-和CD56+CD16+NK细胞数均显著高于其外周血,差异均有统计学意义(P<0.05),CD56+CD16-/CD56+CD16+比值蜕膜组织中虽高于外周血,但无统计学意义(P>0.05)。结论:蜕膜组织中CD56+CD16+NK细胞水平升高以及由此引起的CD56+CD16-/CD56+CD16+比值的变化可能是原因不明复发性流产发生的一个主要因素。     

足月妊娠分娩发动前后孕妇蜕膜中NK细胞及CD4~+CD25~+T细胞的变化

目的:检测足月妊娠分娩发动前后孕妇蜕膜中NK细胞及CD4+CD25+T细胞的变化情况,探讨它们与分娩发动的关系。方法:对40例健康足月孕妇按临产情况分为足月未临产组和足月临产组,收集孕妇蜕膜组织,密度梯度离心法分离出淋巴细胞,流式细胞术(FCM)检测两组中NK细胞、CD4+CD25+T细胞含量。结果:足月临产组的蜕膜NK细胞占蜕膜淋巴细胞的(36.3±6.5)%,足月未临产组蜕膜NK细胞占蜕膜淋巴细胞的(33.9±3.0)%,差异无统计学意义;足月临产组的蜕膜NK细胞表面CDl6的表达明显高于足月未临产组,两者分别为(8.9±1.1)%与(4.6±0.9)%(P<0.05);足月临产组的蜕膜CD4+CD25+T细胞含量明显小于足月未临产组CD4+CD25+T细胞的含量,两者分别为(4.5±0.7)%与(9.1±1.0)%(P<0.05)。结论:足月妊娠分娩发动前、后蜕膜中的NK细胞及CD4+CD25+T细胞发生变化,推测NK细胞与CD4+CD25+T细胞可能参与了分娩发动。     

核仁区嗜银蛋白作为多环芳烃暴露效应标志的研究

目的研究焦炉工人外周血T淋巴细胞核仁区嗜银蛋白(AgNOR)是否可作为多环芳烃暴露的效应标志。方法选取52名焦化厂职工(按焦炉逸散物暴露水平分为高、中、低暴露组)和10名非职业多环芳烃暴露人员(对照组)作为研究对象。采集外周血,经培养、制片、银染,用核仁银染面积/细胞核面积(I/S)衡量T淋巴细胞AgNOR相对含量;同时检测尿1羟基芘的水平,作为接触多环芳烃的内暴露标志。结果高、中、低暴露组和对照组工人尿1羟基芘的平均浓度分别为(16.56±2.77)、(7.17±3.05)、(3.30±2.77)和(3.04±1.58)μmol/mol肌酐,高暴露组与低暴露组和对照组比较,差异有统计学意义;高、中、低暴露组和对照组工人T淋巴细胞AgNOR的I/S值分别为0.056±0.010、0.065±0.013、0.067±0.008和0.076±0.007,高暴露组与其他3组比较以及中、低暴露组与对照组比较,差异均有统计学意义。结论职业多环芳烃暴露可导致尿1羟基芘水平上升和外周血T淋巴细胞AgNOR相对含量下降,提示多环芳烃暴露可损伤T细胞免疫功能,AgNOR有可能作为多环芳烃暴露的效应标志。     

Decreases in CD8+ T, naive (CD4+CD45RA+) T, and B (CD19+) lymphocytes by exposure to manganese fume

To examine the effects of exposure to manganese (Mn) on the cellular and humoral immune system in men, T lymphocyte subpopulations, B (CD19+) lymphocytes, natural killer (NK) cells, and serum immunoglobulins (i.e., IgG, IgA and IgM) together with total T (CD3+) lymphocytes and total lymphocytes were measured in blood samples from 21 welders mainly exposed to Mn fume with blood Mn (BMn) concentrations of 0.6-2.3 (mean 1.4) microg/dl and 21 healthy controls working in the same factory (BMn concentrations: 0.7 to 1.7, mean 1.1 microg/dl). The workers engaged in welding for 6 to 36 (mean 17) yr. All the study subjects were divided into 3 equally sized groups (n=14 for each group) according to BMn concentrations. Numbers of CD8+ T, total T (CD3+), B (CD19+), and total lymphocytes were significantly lower in high-BMn group than those in low-BMn group; the numbers of CD8+ T lymphocytes were significantly lower in moderate-BMn group compared to low-BMn group. After adjusting for age and smoking, significant inverse correlations between BMn concentrations and CD4+CD45RA+ T, CD4+ T, CD8+ T, CD3+ T, and total lymphocytes were found. We conclude that T lymphocytes, especially CD8+ and CD4+CD45RA+ T lymphocytes, as well as CD19+ B lymphocytes are affected by exposure to Mn fume.     

Lymphocyte subpopulations in solvent-exposed workers

Summary To estimate the cellular immune response of workers highly exposed to mixtures of organic solvents, subpopulations of peripheral blood lymphocytes (PBLs) were analyzed. For this, the PBLs of nine floorers (aged 25–58 years, exposure time 8–35 years) were subsequently labelled with monoclonal antibodies OKT 4, OKT 8, OKT 11, anti-Leu 7 and anti-Leu 12. Analysis was made by a FACS IV cell sorter (Becton-Dickinson, USA). The control group consisted of matched pairs of healthy donors. In the exposed group we found a decrease in the OKT 11 (all) T cell fraction, a decrease in the OKT 4 helper cells, an increase in the anti-Leu 7 positive cells, mostly natural killer cells, an important increase in anti-Leu 12 labelled T cells, i.e., human B-lymphocytes, and no differences in the OKT8 suppressor cells. Total fluorescence intensity profiles between the exposed and the unexposed group did not differ, i.e., the marker density on the cell surfaces remained unchanged. Similar changes in lymphocyte subpopulations are found in states of immunodeficiency and immunogenetic forms of aplastic anemia, a disease whose etiological relationship may be due to long-term exposure to organic solvents.     

Decreases of Natural Killer Cells and T-Lymphocyte Subpopulations and Increases of B Lymphocytes Following a 5-Day Occupational Exposure to Mixed Organic Solvents

The authors examined the effects of organic solvents on lymphocyte subpopulations in blood. Natural killer and T-lymphocyte subpopulations and B (CD19+) -lymphocytes were measured with flow cytometry in 16 male rotogravure printers on a Friday and on the following Monday. Numbers of all 3 subpopulations of natural killer cells (i.e., CD57+ CD16+, CD57-CD16+ and CD57+CD16- cells), 2 subpopulations of T lymphocytes (CD4+ CD45RA+ and total CD8+ cells) and total lymphocytes on Friday were significantly fewer than those found on the following Monday. Conversely, the number of B lymphocytes on Friday was significantly larger than the number on Monday. The number of B lymphocytes was significantly correlated with blood toluene levels on Friday. The alteration in the number of CD57+CD16+ NK cells from Friday to the following Monday was correlated inversely with the corresponding change in exposure level of toluene on Friday. The authors suggest that the effects of mixed organic solvents (primarily toluene) are recoverable decreases of natural killer cells and T lymphocytes and increases in B lymphocytes.     

HIV感染者抗病毒治疗前后CD3+CD4+T及NK/NKT细胞变化的临床意义

目的 了解HIV感染者抗病毒治疗前后不同时期CD3+CD4+T和NK/NKT细胞的变化,探讨CD3+CD4+T、NK/NKT细胞作为抗病毒治疗后评价免疫状况指标的临床意义。方法 采用重复测量资料方差分析对40个HIV 感染者抗病毒治疗前、治疗后6个月和12个月的CD3+CD4+T、NK、NKT细胞绝对计数差异进行比较,分析治疗前后CD3+CD4+T细胞计数与NK、NKT细胞计数的相关性。结果 感染者不同时间测得的CD3+CD4+T细胞数量差异有统计学意义（F =68.16,P <0.001）,两两比较差异均有统计学意义（P <0.001）。NK和NKT细胞计数三次测量结果差异有统计学意义（F =10.701,P <0.001;F =44.177,P <0.001）,两两比较发现治疗前分别和治疗后6个月、12个月的绝对计数差异有统计学意义（P <0.001）;CD3+CD4+T与NK、NKT细胞绝对计数的相关性不具有统计学意义。结论 经过1年抗病毒治疗后,CD3+CD4+T淋巴细胞有明显的提高,提示患者免疫状况显著改善。NK和NKT细胞在前6个月增加明显,6个月到12个月期间无明显增加,说明NK和NKT细胞在早期抗病毒中同样发挥了重要作用。NK/NKT细胞的变化可以评价患者治疗后天然免疫状况,但与获得性免疫的CD3+CD4+T淋巴细胞变化没有相关性。     

Decreases of natural killer cells and T-lymphocyte subpopulations and increases of B lymphocytes following a 5-day occupational exposure to mixed organic solvents.

The authors examined the effects of organic solvents on lymphocyte subpopulations in blood. Natural killer and T-lymphocyte subpopulations and B (CD19+) -lymphocytes were measured with flow cytometry in 16 male rotogravure printers on a Friday and on the following Monday. Numbers of all 3 subpopulations of natural killer cells (i.e., CD57+ CD16+, CD57- CD16+, and CD57+ CD16- cells), 2 subpopulations of T lymphocytes (CD4+ CD45RA+ and total CD8+ cells), and total lymphocytes on Friday were significantly fewer than those found on the following Monday. Conversely, the number of B lymphocytes on Friday was significantly larger than the number on Monday. The number of B lymphocytes was significantly correlated with blood toluene levels on Friday. The alteration in the number of CD57+ CD16+ NK cells from Friday to the following Monday was correlated inversely with the corresponding change in exposure level of toluene on Friday. The authors suggest that the effects of mixed organic solvents (primarily toluene) are recoverable decreases of natural killer cells and T lymphocytes and increases in B lymphocytes.     

Association of low job control with a decrease in memory (CD4+ CD45RO+) T lymphocytes in Japanese middle-aged male workers in an electric power plant

To clarify the relationship between perceived job stress and lymphocyte subpopulations, a cross-sectional study was conducted in 231 male electric power plant workers (aged 40 to 60, mean 46 years). Job stress, i.e., job control, job demands, and social support at work, was assessed by means of the Japanese version of the Job Content Questionnaire. Blood samples were taken from all the workers, and numbers of CD4+ T lymphocyte subpopulations, total CD4+ T, T (CD3+) lymphocytes, CD16CD56+ natural killer (NK) cells, total lymphocytes, and white blood cells were determined. After controlling for age, number of cigarettes smoked per day, alcohol drinking, frequency of regular exercise, job demands, and social support at work by the partial correlation coefficients, numbers of memory (CD4+ CD45RO+) T, total CD4+ T, and total T (CD3+) lymphocytes were positively correlated with job control (p<0.05). Neither job demands nor social support at work showed significant correlations with lymphocyte subpopulations. It is suggested that lower job control is associated with a decrease in the number of CD4+ CD45RO+ T lymphocytes in male middle-aged workers.     

Biological monitoring of workers exposed to N-nitrosodiethanolamine in the metal industry.

Biological monitoring of occupational hazards was performed in workers using cutting fluids containing N-nitrosodiethanolamine (NDELA). The study involved a group of 25 male subjects from some metal factories in central Italy who used cutting fluids with an NDELA content of > or = 5 mg/l (high-exposure group) and a group of 37 males exposed to cutting fluids with an NDELA content < 5 mg/l (low-exposure group). For comparison, we recruited a control group consisting of 37 subjects living in the same area. For all subjects, internal dose (urinary excretion of NDELA, mutagens, and thioethers), early biological effects (sister chromatid exchanges in blood peripheral lymphocytes), and urinary excretion of D-glucaric acid (DGA) as an endpoint product in the glucuronidation pathway were assessed. The results showed that only the workers using cutting fluids with NDELA concentrations of > or = 5 mg/l excreted trace amounts of NDELA in their urine. Urine excretion of mutagens was similar in the two exposure groups and in the controls. High-exposure subjects had a higher mean value of urinary thioethers than low-exposure and control subjects, but no differences were found in urinary DGA or lymphocyte sister chromatid exchange among the three groups. Smoking status increased the mean values of all the biomarkers, and coffee drinking was associated with urinary DGA excretion.     

手术前后卵巢癌患者外周血T细胞亚群及CD4~+CD25~+调节性T细胞表达及临床意义

目的:探讨手术前后卵巢癌患者外周血T细胞亚群及CD4+CD25+调节性T细胞的变化及其临床意义。方法:采用流式细胞术检测80例卵巢癌患者外周血T淋巴细胞亚群、NK细胞及CD4+CD25+调节性T细胞水平。结果:与对照组相比,卵巢癌患者外周血中CD3+,CD4+,CD4+/CD8+比值及NK细胞含量均降低(P0.05),CD8+升高(P0.05);随着疾病进展Ⅲ期+Ⅳ期与Ⅰ期+Ⅱ期比较CD3+,CD4+,CD4+/CD8+比值及NK细胞含量均降低(P0.05),CD8+升高(P0.05)。卵巢癌患者外周血CD4+CD25+细胞比例高于正常对照组(P0.05);手术后卵巢癌患者T细胞亚群比例与术前比较并未明显恢复(P0.05),但CD4+CD25+调节性T细胞水平有所恢复(P0.05)。结论:卵巢癌患者免疫功能低下,术后短期并不能恢复,CD4+CD25+调节性T细胞水平升高,术后明显恢复,提示其在免疫耐受中起重要作用。     

非孕与早孕妇女外周血及宫内膜和蜕膜组织自然杀伤细胞亚群的变化

目的:探讨非孕与早孕妇女的外周血、宫内膜和蜕膜组织之间的自然杀伤(NK)细胞亚群的差异,以及雌、孕激素对外周血、宫内膜和蜕膜组织NK细胞的影响。方法:用流式细胞仪检测非孕和早孕妇女外周血、宫内膜和蜕膜组织NK细胞表面标记CD56和CD16分子,以及用放射免疫沉淀法测定外周血清雌二醇(E2)和孕酮(P4)水平,并进行比较分析。结果:早孕外周血组NK细胞的CD56+CD16-、CD56+CD16+和CD56-CD16+3组亚群的百分率均明显高于非孕外周血组(分别为P≤0.013、P<0.001、P≤0.001);非孕宫内膜组的NK细胞以CD56+为主,为20.82%,且其CD56+CD16-的百分率明显高于其外周血组,而CD56-CD16+的百分率明显小于外周血组(P≤0.001),两组的CD56+CD16+的百分率无差异(P>0.05),非孕宫内膜组CD56+CD16-的百分率明显高于CD56+CD16+和CD56-CD16+(均为P<0.001),非孕外周血组的NK细胞以CD16+为主,且其CD56-CD16+的百分率明显高于CD56+CD16-和CD56+CD16+(均为P<0.001)。早孕蜕膜组的NK细胞以CD56+为优势,为62.42%。早孕蜕膜组NK细胞的CD56+CD16-、CD56+CD16+和CD56-CD16+3组亚群的百分率均明显高于非孕宫内膜组(均为P<0.001),而早孕周围血中的NK细胞以CD56+CD16+和CD16+为主,分别为9.93%和10.65%,且与CD56+CD16-比较均有显著性差异(均为P<0.001),早孕外周血组CD16+NK细胞的百分率明显高于蜕膜组(P≤0.001),且两组CD56+CD16+的百分率无差异(P>0.05)。结论:孕激素能明显促进宫内膜CD56+NK细胞的增殖和分化,雌、孕激素水平的协同升高可增加外周血和宫内膜组织的CD56+、CD56+CD16+、和CD16+NK细胞亚群的百分率;CD56+CD16+NK细胞在早孕外周血和蜕膜组织之间,以及在非孕外周血和宫内膜组织之间均可能起免疫调控作用。     

Increase in Memory (CD4+CD29+ and CD4+CD45RO+) T and Naive (CD4+CD45RA+)T-Cell Subpopulations in Smokers

To examine the effects of smoking on lymphocyte subpopulations, we measured the following cell subpopulations: CD4+ T-cell subpopulations (i.e., CD4+CD29+, CD4+ CD45RO+, and CD4+CD45RA+ cells); CD8+ T-cell subpopulations (i.e., CD8+CD11a+ and CD8+CD11b+ cells); and natural killer cell subpopulations (i.e., CD16+CD57-, CD16+CD57+, and CD16-CD57+ cells). We measured these subpopulations, together with total CD4+ T, total CD8+T, total CD3+T, B (CD19+), and total lymphocytes, in 10 male heavy smokers, 38 male light-to-moderate smokers, and 33 male nonsmokers. The mean ages were 30 y, 31 y, and 32 y, respectively, and ages did not vary significantly among the smokers. CD4+CD29+ and CD4+CD45RO+ (memory T) cells in heavy smokers were significantly more numerous than those in light-to-moderate smokers and nonsmokers. Also, these memory T-cell subpopulations were significantly more numerous in light-to-moderate smokers than in non-smokers. The number of CD4+CD45RA+ (naive T) cells was significantly larger in heavy smokers than nonsmokers; numbers of CD4+CD45RO+ T and CD4+CD29+ T cells (memory T cells) were significantly correlated with daily cigarette consumption. Numbers of CD3+ T, CD4+ T, CD19+ B, and total lymphocytes in heavy smokers were significantly larger than in nonsmokers. There were significantly more CD3+ T, CD4+ T, and total lymphocytes in light-to-moderate smokers than in nonsmokers. The numbers of CD4+ T lymphocytes in heavy smokers were significantly larger than in light-to-moderate smokers. Perhaps CD4+ T cell subpopulations, especially memory T cells, are most susceptible to the effects of smoking on lymphocyte sub-populations.     

焦炉工人外周血淋巴细胞热休克蛋白72水平及与DNA损伤的关系

目的研究焦炉逸散物对焦炉工人外周血淋巴细胞热休克蛋白72（Hsp72）水平的影响及与DNA损伤的关系，探讨Hsp72在细胞损伤保护中的意义。方法选取267名焦炉工人和30名对照，以Western blot法检测外周血淋巴细胞Hsp72的水平，彗星试验检测DNA损伤水平，个体采样采集作业环境空气样本，高效液相色谱法测定环境苯并[a]芘浓度。结果高暴露组工人外周血淋巴细胞Hsp72水平（G±SG）和Olive尾矩（G±SG）分别为1．24±0．42和4．49±1．24，明显高于低暴露组（1．01±0．35和2．99±1．10）和对照组（0．85±0．34和2．40±1．00），差异有统计学意义（P〈0．05）。以全体研究对象Hsp72中位数为界值，将研究对象分为Hsp72高表达组和低表达组，Hsp72高表达的人数相对比率在对照组、低暴露组、高暴露组分别为36．7％、43．1％和58．3％，呈逐渐增高趋势，差异有统计学意义（P=0．003）。在Hsp72高表达组，Hsp72表达水平随着暴露等级升高而升高，其中高暴露组与对照组的差异有统计学意义（P〈0．05），但各组之间Olive尾矩的差异无统计学意义（P〉0．05）。在Hsp72低表达组中，各组Hsp72水平的差异无统计学意义（P〉0．05），而Olive尾矩随暴露等级升高而升高，其中高暴露组与低暴露组和对照组比较，差异有统计学意义（P〈0．01），且明显高于Hsp72高表达组的高暴露组工人。高暴露组Hsp72水平与Olive尾矩呈负相关（r=0．503，P〈0．01）。结论焦炉逸散物可诱导焦炉工人外周血淋巴细胞Hsp72水平升高，Hsp72对细胞DNA损伤具有保护作用。     

Estimating the contribution of inhalation exposure to di-2-ethylhexyl phthalate (DEHP) for PVC production workers,using personal air sampling and urinary metabolite monitoring

Because of troubling reports of high urinary metabolite levels and adverse reproductive health effects in workers exposed to di(2-ethylhexyl)phthalate (DEHP) in occupational settings, concern about exposure to DEHP in occupational settings is increasing. However, the contributions of different routes of exposure to DEHP are unclear. We used personal air sampling and biomonitoring to determine the contribution of inhalation exposure to the body burden of DEHP in the workplace. Eighty-nine workers (high-exposure group: 66 raw-materials workers; low-exposure group: 23 administrative workers) were recruited from three polyvinyl chloride (PVC) factories. Urinary levels of mono(2-ethylhexyl) phthalate (MEHP), (mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) were measured in pre-shift and post-shift samples. The geometric means of airborne concentrations of DEHP were 5.3 μg/m³ (low-exposure group) and 32.7 μg/m³ (high-exposure group) (P < 0.01). Correlation analysis showed a consistently significant association between airborne DEHP concentration and urinary DEHP metabolite levels in the high-exposure group. Calculating daily DEHP intake based on total urinary metabolite levels showed that the geometric means of total daily urinary metabolite levels of DEHP were 9.2 μg/kg/day (low-exposure group) and 15.5 μg/kg/day (high-exposure group) (P < 0.01). A quartile analysis of all workers showed a significant trend toward an association between the individual contribution of inhalation exposure to DEHP and urinary DEHP metabolite levels, for which the mean inhalation contribution was 46.7% in the highest quartile. We conclude that inhalation-absorbed airborne DEHP significantly increased the total body burden of DEHP in these occupationally exposed workers.     

艾叶燃烧物清除自由基作用的观察

  目的  了解吸入不同浓度艾烟对大鼠肺组织结构及血清中CD4⁺/CD8⁺的影响,探讨艾烟所导致的肺组织形态改变及免疫调节作用与其浓度的关系,为临床安全使用艾灸疗法提供理论依据。  方法  清洁级2月龄雄性Wistar大鼠40只,随机分为正常对照组及低、中、高浓度艾烟暴露组4组,每组10只,分别暴露于无艾烟环境及10、25、70 g艾绒完全燃烧后的艾烟中,每天2 h,持续30 d;采用显微镜观察大鼠肺组织形态变化,应用流式细胞术检测大鼠外周血中CD4⁺及CD8⁺ T淋巴细胞百分率,并计算CD4⁺/CD8⁺ 值。  结果  高浓度艾烟暴露组大鼠肺组织中出现炎症反应,低、中浓度艾烟暴露组大鼠肺组织无显著改变;高浓度艾烟暴露组大鼠CD8⁺ T淋巴细胞百分率为（37.13 ± 2.23）%,均高于正常对照组及低、中浓度艾烟暴露组CD8⁺ T淋巴细胞百分率的（34.45 ± 5.14）%、（33.84 ± 3.23）%、（34.19 ± 4.27）%（均P < 0.05）;高浓度艾烟暴露组CD4⁺/CD8⁺ 值为（1.46 ± 0.29）,均低于正常对照组及低、中浓度艾烟暴露组CD4⁺/CD8⁺ 值的（1.53 ± 0.43）、（1.55 ± 0.37）、（1.58 ± 0.41）（均P < 0.05）。  结论  不同浓度艾烟对大鼠的肺组织形态及免疫系统均有影响,其中低、中浓度的艾烟较高浓度的艾烟对肺脏损伤小,且能够更好地调节免疫水平,提高机体免疫功能。     

CD4+CD25+T细胞在溃疡性结肠炎患者中的表达及意义

目的研究溃疡性结肠炎（UC）患者外周血CD4＋CD25＋调节性T细胞和其特异性标志物Foxp3的表达及其在UC不同病期的变化,探讨其在UC发病机制中的意义。方法研究纳入2007年2月至2008年12月在我院就诊的UC患者40例,其中活动期23例,缓解期17例;同时选择33例肠易激综合征（IBS）患者及32名健康者作为对照。用流式细胞仪检测UC患者、IBS患者和正常对照者的外周血CD4＋CD25＋T细胞阳性率,用RT-PCR检测外周血单个核细胞（PBMC）中Foxp3mRNA的表达,用酶联免疫吸附实验检测血清中白细胞介素-10（IL-10）和转化生长因子-β（TGF—β）的浓度。结果活动期和缓解期UC患者、IBS患者、正常对照者外周血CD4＋T细胞总数相比差异无统计学意义（P=0．126）。CD4＋CD25＋T细胞在CD4＋T细胞中所占比例在活动期和缓解期UC患者中均明显低于IBS患者和正常对照组（P均〈0．01）,活动期患者较缓解期患者更低（P〈0．001）,并且与疾病活动指数（r=-0．660,P〈0．001）及红细胞沉降率（r=-0．572,P=0．001）均呈显著负相关,而IBS患者和正常对照者间差异没有统计学意义（P=0．343）。PBMC中Foxp3mRNA的表达在活动期和缓解期UC患者均明显低于IBS患者和正常对照组（P均〈0．001）。而血清IL-10和TGF—β的浓度在活动期和缓解期UC患者、IBS患者和正常对照者4组间无明显差异（P均〉0．05）。结论活动期UC患者外周血CD4＋CD25＋调节性T细胞明显降低,缓解期UC患者的表达有所升高,并且与临床疾病活动相关,提示这类细胞可能参与了UC疾病的发生发展,Foxp3表达降低可能是导致CD4＋CD25＋T细胞发育障碍的重要因素。