甲醛对从业工人外周血淋巴细胞的遗传学效应

甲醛(FA)是一种诱变剂,同时也是一种人类的可疑致癌剂。在多种体外诱变试验中都得到了阳性结果,在啮齿动物中,FA可以引起鼻腔部和鼻咽部癌。对上海石化总厂生产过程中接触FA的21名男性工人进行了染色体分析,14名非生产工人作为对照。FA生产环境中的空气浓度年平均为2.51mg/m3。结果与对照组比较,SCE没有显著改变,而染色体的畸变率明显高于对照组(P<0.05)。畸变类型包括单体型和染色体型两种,主要是单体断裂、无着丝点断片、双着丝点和非整倍体。证明FA是一种染色体断裂剂。我国1979年颁发的FA空气中最高容许浓度3mg/m3对长期职业接触FA的人群而言,仍是不安全的。     

Mutagen sensitivity in peripheral lymphocytes as a risk indicator

A total of 266 individuals were selected to represent the normal distribution of age, sex, and blood pressure in the general population of Dalby, Sweden. A method designed to estimate an individual's sensitivity to mutagenic exposures has been established and is based on in vitro N-acetoxy-2-acetylaminofluorene (NA-AAF) stimulation of unscheduled DNA synthesis (UDS) in resting peripheral lymphocytes. High levels of NA-AAF-induced UDS, or high mutagen sensitivity, correlated to old age and to high blood pressure. The general health status was described in relation to the estimated mutagen sensitivity by collecting, from the national health insurance records, information regarding all disease episodes during a five-year period. It was found that the incidence of cardiovascular, infectious, and malignant diseases was considerably higher among those individuals assigned high mutagen risk by the NA-AAF-induced UDS method. These data were taken as evidence in support of the hypothesis that lymphocyte sensitivity to the induction of DNA damage by NA-AAF indicates the relative risk of individuals' developing the major diseases important in general health care.     

氯化镉诱发大鼠血淋巴细胞HPRT基因位点突变频率的研究

目的了解氯化镉对大鼠外周血淋巴细胞HPRT基因位点的影响,寻找化学诱变物致机体损伤的早期检测的指标.方法采用多核细胞法研究化学诱变物氯化镉对大鼠血淋巴细胞HPRT基因位点的影响及突变频率.结果氯化镉可诱发大鼠血淋巴细胞HPRT基因位点突变,突变频率随着染毒浓度的增加而升高,突变频率Y(×10-3)与氯化镉浓度C(mg/kg)之间存在剂量-效应关系.结论氯化镉对大鼠血淋巴细胞HPRT基因位点及突变频率有影响,HPRT基因突变频率检测有望作为早期的效应标志物,用于接触环境致突变物人群的分子流行病学调查.     

Reduced benzo-a-pyrene activation potential in lymphocytes from chronic alcoholics

The effect of chronic ethanol consumption on the cellular metabolism of benzo-a-pyrene (BaP) is investigated in human peripheral lymphocytes obtained from 6 proven alcoholic addicts and 5 healthy donors. Lymphocytes convert BaP to dihydrodiols, diol-epoxides, phenols, quinone derivatives and polyhydroxylated forms. Sulfate, glucuronide and glutathione conjugates are also detected. The average production of metabolites is much lower in lymphocytes of alcoholics and a net global decrease of "active" metabolite production, i.e., diols and BPDE, is also observed. In contrast, conjugated metabolites are formed in increased amounts. The data indicate that the metabolism of BaP in lymphocytes from chronic alcoholics is characterized essentially by a lowered rate of metabolized BaP and a reduction of their BaP activation potential, as seen by the increased production of conjugated metabolites and the markedly decreased protein-bound active mutagen.     

切尔诺贝利事故辐射受照人员淋巴细胞核的形态变化

目的观察受照射的切尔诺贝利事故清理工作者外周血淋巴细胞核特殊形态变化。方法选取切尔诺贝利事故清理工作者作为试验组,采用常规方法取指尖外周血制备涂片,空气干燥,对氨基苯甲酸混合,Giemsa法染色,光镜下计数每人500个细胞样本,观察记录不同特殊形态核发生率,进行统计学处理。结果大多数受照射对象都出现较多带有尾状突起的淋巴细胞。根据这些核上突起的尾状物形态特征将其分为16种类型并分别记录了每种尾状突起细胞的发生率并进行分布率分析。结论受照射淋巴细胞核尾状突起变化可能是一种有意义的受照射标记物,对于更加详尽获取辐射生物效应信息,回顾性研究辐射剂量效应可能具有理论和实践价值。     

A mathematical model and CD4+ lymphocyte dynamics in HIV infection.

The paper presents a model of CD4 + lymphocyte dynamics in HIV-infected persons. The model incorporates a feedback mechanism regulating the production of T lymphocytes and simulates the dynamics of CD8 + lymphocytes, whose production is assumed to be closely linked to that of CD4 + cells. Because CD4 + lymphocyte counts are a good prognostic indicator of HIV infection, the model was used to simulate such therapeutic interventions as chemotherapy and active and passive immunization. The model also simulated the therapeutic administration of anti-CD8 antibodies; this intervention was assumed to activate T-cell production by activating a feedback mechanism blocked by the high numbers of CD8 + lymphocytes present in HIV-infected persons. The character and implications of the model are discussed in the context of other mathematical models used in HIV infection.     

Adaptive response in human blood lymphocytes exposed to non-ionizing radiofrequency fields: resistance to ionizing radiation-induced damage

The aim of this preliminary investigation was to assess whether human peripheral blood lymphocytes which have been pre-exposed to non-ionizing radiofrequency fields exhibit an adaptive response (AR) by resisting the induction of genetic damage from subsequent exposure to ionizing radiation. Peripheral blood lymphocytes from four healthy donors were stimulated with phytohemagglutinin for 24 h and then exposed for 20 h to 1950 MHz radiofrequency fields (RF, adaptive dose, AD) at an average specific absorption rate of 0.3 W/kg. At 48 h, the cells were subjected to a challenge dose (CD) of 1.0 or 1.5 Gy X-irradiation (XR, challenge dose, CD). After a 72 h total culture period, cells were collected to examine the incidence of micronuclei (MN). There was a significant decrease in the number of MN in lymphocytes exposed to RF + XR (AD + CD) as compared with those subjected to XR alone (CD). These observations thus suggested a RF-induced AR and induction of resistance to subsequent damage from XR. There was variability between the donors in RF-induced AR. The data reported in our earlier investigations also indicated a similar induction of AR in human blood lymphocytes that had been pre-exposed to RF (AD) and subsequently treated with a chemical mutagen, mitomycin C (CD). Since XR and mitomycin-C induce different kinds of lesions in cellular DNA, further studies are required to understand the mechanism(s) involved in the RF-induced adaptive response.     

Immunomodulatory treatment of lymphopenia after infectious mononucleosis

Persistent lymphopenia of various intensity has been noted in 45% of persons who had a history of infectIous mononucleosis. The group consisted od 500 patients, (236 males and 264 females). In all of them the diagnosis of mononucleosis had been based on the characteristic clinical signs and symptoms and changes in the blood picture and confirmed by the non-specific and/or specific serologic tests. In 33 persons (10 males and 18 females) the total number of lymphocytes varied from 884 to 992 per 1 cmm, the distribution being as follows: B lymphocytes--146 to 198, CD4--482 to 645 and CD8--245 to 364 per 1 cmm. 18 persons (18 males and 10 females) were given thymosine (TFX) subcutaneously for 30 days in the dose of 0.02 g daily, the remaining 15 (7 males and 8 females) received 3.0 g of isoprinosine per day for the same period. The total lymphocytes count and that of B, CD4 and CD8 was performed before and after the treatment and then followed once a month until 180 days since the treatment had been started. The TFX therapy was repeated after 8-12 months since the end of the first course in 3 patients and that with isoprinosine in 4. The strategy and the examination pattern were the same as before, control examinations being performed every 6 months and final analysis was done after 5 years of follow-up. Among the 33 patients who received immunomodulating treatment, normalisation of the lymphocytes count appeared in 24 (64%). Among the 12 persons with less pronounced lymphopenia, who did not received any treatment, spontaneous normalisation appeared in 5 (40%). It may be therefore assumed, that in persons with the history of infectious mononucleosis with persistent marked lymphopenia, thymosine and isoprinosine may be used in the therapy as additional immunomodulators.     

Mutagen sensitivity, smoking habits and enzyme induction in healthy middle-aged men

Unscheduled DNA synthesis (UDS) (excision-repair) of N-acetoxy-2-acetylaminofluorene (NA-AAF) damage to the DNA of human lymphocytes and levels of ³H-labeled NA-AAF bound to the DNA (carcinogen binding) of lymphocytes after 18 hr of culturing were measured in a consecutive subsample of healthy middle-aged males attending a multiphasic health screening program at the Department of Preventive Medicine in Malmö during 3 weeks in November-December 1981, and compared relative to their smoking habits, body weight, serum cholesterol, and γ-glutamyltransferase levels as well as aryl hydrocarbon hydroxylase inducibility. This study group numbered 66 males and was uniform in sex, age, and investigation time. No case of significant arterial hypertension was present. The UDS and carcinogen binding results showed no correlation with the other factors measured, with the exception of smoking which was strongly (P < 0.01) associated with increasing levels of both the UDS and carcinogen binding values. It is concluded that under ordinary circumstances smoking may represent the most important exogenous factor which may modulate risk to cardiovascular disease and cancer by influencing individual mutagen sensitivity.     

Trout hepatic enzyme activation of aflatoxin B1 in a mutagen assay system and the inhibitory effect of PCBs

In summary, it was demonstrated that the trout PMF may be successfully employed in the Ames mutagen assay method by utilization of proper salts solution and a metabolic preincubation period at 25 degrees C. It has also been observed that, unlike the rat, pretreatment of rainbow trout with various PCBs decrease the mutagen assay response to AFB.     

The genoprotective activity of resveratrol on aflatoxin B₁-induced DNA damage in human lymphocytes in vitro

Aflatoxin B? (AFB?) has been consistently shown to be a potent mutagen and carcinogen in humans and animals. On the other hand, resveratrol (RSV), a polyphenol, has several positive biological actions such as protection of cells against DNA damage. In the present study, the antigenotoxic effect of RSV was studied against a genotoxic dose of AFB? using the damage parameters of chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) in cultured human lymphocytes. Whole blood samples from three healthy male donors were used for this experiment and the effects of various concentrations of RSV (0, 10, 15, 25, 40, 75 and 100 μM) and AFB? (10 μM) were tested. The results revealed that the frequencies of SCEs and CAs in lymphocytes were significantly (p < 0.05) increased by AFB? as compared to controls. The results also showed that RSV was not genotoxic. Moreover, the number of SCEs and micronuclei induced by AFB? could be significantly minimized by the presence of RSV. Our results suggest for the first time that RSV can antagonize the ability of AFB? to cause DNA damage that leads to the formation of SCEs and CAs.     

扬州市放射工作人员外周血淋巴细胞微核细胞率分析

目的 了解扬州市放射工作人员外周血淋巴细胞微核细胞率的总体水平,为放射工作人员职业健康监护提供依据。
方法 对2018年扬州市2 124名放射工作人员的外周血淋巴细胞微核细胞率进行统计分析和评价。
结果 2 124名放射工作人员外周血淋巴细胞微核细胞率均≤ 6‰,在正常范围内。上岗前放射工作人员微核自发率与年龄呈正相关关系（r_s=0.513,P < 0.01）,20~29岁和≥ 50岁年龄段上岗前人员的微核细胞率均低于在岗及离岗人员的微核细胞率（P < 0.05）。微核细胞率随着工龄增加有逐渐升高的趋势（r_s=0.239,P < 0.01）;不同工种放射工作人员的微核细胞率差异有统计学意义（P < 0.01）,其中从事工业应用和核医学的放射工作人员较高。不同级别放射工作单位之间微核细胞率差异也有统计学意义（P < 0.01）,其中一级医院及牙科门诊的放射工作人员略高。
结论 扬州市放射工作人员职业健康总体状况较好,放射工作人员外周血淋巴细胞微核细胞率较低,且与年龄、工龄和工种有关。
     

Microwaves from GSM mobile telephones affect 53BP1 and gamma-H2AX foci in human lymphocytes from hypersensitive and healthy persons

The data on biologic effects of nonthermal microwaves (MWs) from mobile telephones are diverse, and these effects are presently ignored by safety standards of the International Commission for Non-Ionizing Radiation Protection (ICNIRP). In the present study, we investigated effects of MWs of Global System for Mobile Communication (GSM) at different carrier frequencies on human lymphocytes from healthy persons and from persons reporting hypersensitivity to electromagnetic fields (EMFs). We measured the changes in chromatin conformation, which are indicative of stress response and genotoxic effects, by the method of anomalous viscosity time dependence, and we analyzed tumor suppressor p53-binding protein 1 (53BP1) and phosphorylated histone H2AX (gamma-H2AX), which have been shown to colocalize in distinct foci with DNA double-strand breaks (DSBs), using immunofluorescence confocal laser microscopy. We found that MWs from GSM mobile telephones affect chromatin conformation and 53BP1/gamma-H2AX foci similar to heat shock. For the first time, we report here that effects of MWs from mobile telephones on human lymphocytes are dependent on carrier frequency. On average, the same response was observed in lymphocytes from hypersensitive and healthy subjects.     

UDS and SCE in lymphocytes of persons occupationally exposed to low levels of ionizing radiation

Unscheduled DNA synthesis induced by in vitro UV irradiation was investigated in lymphocytes of persons occupationally exposed to low doses of ionizing radiation (maximum registered radiation dose: 98 mrad/month). For radiation exposures greater than 14 mrad/month above background level, increased rates of UDS after in vitro UV irradiation of lymphocytes were found. The bromodeoxyuridine differential chromatid labeling technique was applied to the examination of spontaneous and Mitomycin C (MMC)-induced sister chromatid exchanges (SCE) in the same population. No statistically significant difference could be determined in spontaneously occurring SCEs, while MMC induced SCEs were significantly reduced in persons exposed to radiation doses greater than 14 mrad/month, thus indicating increased repair capability for DNA lesions inflicted by a second insult after protracted low-dose irradiation.     

An evaluation of possible effects on health following exposure to ethylene oxide

A study was made of the effects of ethylene oxide (ETO) on the health of sterilizer workers and other personnel exposed while using ETO for sterilization of disposable medical devices. The only significant findings were obtained by chromosomal analysis of cultured lymphocytes harvested from the workers. There were significant differences in the numbers and types of chromosomal aberrations between the exposed workers and the nonexposed controls. Quadriradial and triradial chromosomal forms, which are rarely found in nonexposed populations, were increased in exposed workers. Increased numbers of sister chromatid exchanges (SCE) were found in the cultured lymphocytes of some, but not all, exposed persons during the 2 yr of study. Thirteen workers were removed from exposure in 1979 because of increased numbers of aberrant cells. Follow-up over 4 yr has not shown a significant improvement, except for a moderate reduction in SCE. Recommendations are given for a surveillance of persons working with or exposed to ethylene oxide.     

Analysis of genotoxic effects of individual factors on chemical industry workers

The article provides data on the study of occupational and non-occupational factors relating to the prevalence of early spontaneous abortions in couples engaged in fertilizer production. A higher degree prevalence of early spontaneous abortions was detected in several groups affected by specific factors. As this degree of prevalence was found in the groups in which it was only the father that had been exposed to the specific hazardous factors, it was considered that the factors in question either hindered the mutagen tolerance or were capable of their own germ cell mutagen action. It was established that lowered mutagen tolerance related to early abortions was markedly higher in groups exposed to organic substances' compounds and industrial noise.     

类黄酮和维生素的抗突变研究

目的 :　比较类黄酮、维生素和咖啡碱等对不同致突变物的抗突变活性特征、作用及影响。方法 :　用改进型的 Ames试验方法、鼠伤寒沙门氏菌 (Salmonella tyhimurim)的变异种 TA系列菌株、直接致突变物的 1 -硝基芘 (1 -NP)和间接致突变物的色氨酸热解产物 (Trp-P-1 )对测试物进行抗突变效果的比较。结果 :　植物性食物中富含的黄烷醇 (儿茶素 )类、黄酮醇类、酚酸类对Trp-P-1比 1 -NP的抗突变活性高 ;维生素 C、B族和 A对 1 -NP的抗突变性高于类黄酮物质 ,而对Trp-P-1的抗突变性则较低 ,但均有抗突变的剂量效应关系 ;咖啡碱与儿茶素合并使用时对 Trp-P-1的致突变有拮抗现象作用。结论 :　类黄酮对抗突变有较好的作用 ;维生素有辅助和互补作用 ;而咖啡碱的抗突变性不明显     

HIV感染者和AIDS患者T淋巴细胞亚群的变化及其临床意义

目的探讨衡阳地区HIV感染者和AIDS患者T淋巴细胞亚群的免疫病理改变情况及其临床意义。方法收集59例HIV感染者（HIV组）、50例AIDS患者（AIDS组）、31例健康体检人员（正常对照组）的抗凝血,用流式细胞仪单平台技术检测外周血T4及T8淋巴细胞。结果正常对照组、HIV组、AIDS组外周血T4细胞计数分别为（673±362,337±278）、（129±124）（个/μl）,组间比较,正常对照组明显高于HIV组和AIDS组（P〈0.01）;T8细胞计数分别为（478±243）、（940±844）、（707±636）（个/μl）,HIV组明显高于对照组（P〈0.05）;T4细胞与T8细胞比值（TH/S）分别为（1.49±0.90）、（0.39±0.38）、（0.18±0.17）,正常对照组明显高于HIV组和AIDS组（P〈0.05）。结论综合分析T淋巴细胞不同亚群的改变,能反映HIV感染者和AIDS患者的免疫受损情况和疾病的严重程度。     

与SARS病例密切接触医务人员免疫水平分析

目的　分析SARS流行期间小汤山医疗队医务人员机体免疫水平 ,评价小汤山医院SARS防护措施。方法　采用流式细胞术和血细胞分析仪分别检测小汤山医疗队医务人员、SARS流行期间北京驻军某部健康官兵的外周血白细胞总数、淋巴细胞群CD3 T淋巴细胞 (包括CD4、CD8细胞 )、CD 56NK细胞、CD 19B细胞绝对数 ,并与SARS流行前健康人群正常值比较。结果　小汤山一线医务人员和SARS流行期间健康官兵的白细胞总数、淋巴细胞及其亚群CD 3 T淋巴细胞、CD 4 细胞、CD 8细胞、CD 19B细胞绝对数均降低 ,而CD 56NK细胞升高 ,与SARS流行前健康人群正常值比较 ,有显著性差异 (P <0 0 0 1,P <0 0 5 ) ,一线医务人员与同期健康官兵比较无显著性差异。结论　SARS流行后医务人员的免疫功能降低主要与心理应激有关 ;采取隔离防护措施可有效保护应激状态下医务人员的安全。     

Adsorption of direct-acting and indirect-acting mutagens by various dietary fibers

The protective effect of dietary fiber on human cancer has received great attention during the last decades. Because dietary fiber constitues a large group of complex polysaccharides with various solubilities, degrees of lignification, chemical compositions and structural arrangements, several mechanisms for their effects have been proposed. In this study, in vitro binding capacities of various dietary fibers (potato fiber and glucomannan) and dietary fiber constituents (pectic acid and cellulose) against indirect mutagen 2-amino-3-methyl-3H-imidazo (4,5-f) quinoline (IQ) and direct-acting mutagen sodium azide were investigated. Direct-acting mutagen sodium azide was not adsorbed to the dietary fiber and dietary fiber constituents at 0 C, pH 4.5 and 37 C, pH 7.0. However, indirect-acting mutagen 2-amino-3-methyl-3H-imidazo (4,5-f) quinoline (IQ) were sorbed by them in variable ratios at 0 C, pH 4.5 and 37 C, pH 7.0. The differences between the in vitro binding capacities of the samples at two experimental conditions were found to be statiscially significant (P < 0.01). IQ was not released from the dietary fibers and constituents in distilled water.