妊高征血清中MDA和SOD含量测定及意义

测定了３１例妊高征患者及２４例正常孕妇在孕３６～４１ｗ血清丙二醛（ＭＤＡ）和超氧化物歧化酶（ＳＯＤ）的含量。结果：妊高征组血清ＭＤＡ含量明显高于正常孕妇组（Ｐ＜０．０１），而ＳＯＤ含量明显低于正常孕妇组（Ｐ＜０．０１）。随着病情的加重，中、重度好高征患者ＭＤＡ含量升高与ＳＯＤ含量降低具有明显负相关性（ｒ＝－０．６．Ｐ＜０．０５）。提示：妊高征的发生发展与体内氧化抗氧化之间的平衡失调有密切关系，作者认为，测定血清ＭＤＡ和ＳＯＤ水平时好高征患者的病情判断和临床治疗新途径提供了理论依据。     

电焊作业臭氧对人体氧化应激作用研究

目的探讨电焊作业中产生的臭氧是否引起电焊作业者体内氧化应激和氧化损伤。方法采用分光光度法检测电焊作业者（WOs）血浆维生素C（VC）、维生素E（VE）含量，红细胞超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPX）活性和过氧化脂质（LPO）含量。结果与健康组比较，电焊作业者组的血浆VC和VE均值以及红细胞SOD、CAT和GPX平均值显著降低，而红细胞LPO均值显著升高。随着电焊作业者接触臭氧时间的延长，除CAT之外，VC、VE、SOD和GPX值均逐渐降低，LPO值逐渐升高。随着作业场所臭氧浓度的升高，电焊作业者VE、VE、SOD、CAT和GPX值逐渐降低，LPO值逐渐升高。实验参数的可靠性分析，可靠性系数为0．8021，P〈0．0001；标化可靠性系数0．9577，P〈0．001。结论电焊作业者体内存在由长期接触臭氧而引起的氧化应激，进而诱发潜在的氧化和脂质过氧化损伤。     

Cr（VI）对人胚肺细胞p53及抑癌基因p21（WAF1）表达的影响

目的研究人类致癌物Ｃｒ（ＶＩ）对抑癌基因ｐ５３及其下游的抑癌基因ｐ２１（ＷＡＦ１）在多阶段致癌中的作用。方法采用Ｎｏｒｔｈｅｒｎ杂交技术，观察不同浓度Ｋ２Ｃｒ２Ｏ７对人胚肺细胞内ｐ５３及ＷＡＦ１表达的影响。结果Ｃｒ（ＶＩ）对ｐ５３表达的影响呈双相作用，０～１．２５０μｍｏｌ／Ｌ范围内Ｋ２Ｃｒ２Ｏ７抑制ｐ５３的表达；１．２５０～５．０００μｍｏｌ／ＬＫ２Ｃｒ２Ｏ７可刺激ｐ５３的表达。ＷＡＦ１的变化趋势与ｐ５３相一致，即１．２５０μｍｏｌ／ＬＫ２Ｃｒ２Ｏ７可明显抑制ＷＡＦ１的表达，而随着Ｋ２Ｃｒ２Ｏ７浓度的增加，ＷＡＦ１的表达也呈升高趋势。结论低剂量Ｋ２Ｃｒ２Ｏ７影响下的ｐ５３及ＷＡＦ１的低表达可能在Ｃｒ（ＶＩ）多阶段致癌中起重要作用。     

苯并[a]芘的细胞毒性及诱导IL-1β和IL-8表达作用研究

目的 探讨不同浓度苯并[a]芘（BaP）对人肺癌（淋巴结转移）NCI-H292的细胞毒性及其对NCI-H292细胞炎性因子分泌的影响。方法 取对数期生长的NCI-H292细胞，分别以不同剂量BaP（0、4、8、16和32 μmol/L） 染毒24、48和72 h后，采用实时无标记细胞分析系统（RTCA）法检测细胞存活率，ELISA法检测细胞内白介素-1β（IL-1β）和白介素-8（IL-8）水平。本实验按照5×3析因设计。结果 与对照组相比，各剂量BaP染毒组在24、48和72 h时间点细胞存活率均显著降低（P<0.001），细胞存活率与染毒剂量之间呈高度负相关关系（r1=-0.986、-0.974和-0.993，P<0.01）；与同剂量组24 h时比较，各实验组在染毒48 h和72 h细胞存活率均显著升高（P<0.001）， 细胞存活率与染毒时间之间呈高度正相关关系（r2=0.958、0.996、0.994、0.999和1.000，P<0.01）。NCI-H292细胞内IL-1β水平在染毒剂量和染毒时间上有交互效应（P<0.001），在48 h和72 h时BaP高剂量（8~32 μmol/L）染毒组IL-1β水平均呈随着染毒剂量升高而降低（P<0.01），72 h时低剂量BaP染毒组IL-1β水平则呈随着染毒剂量升高而升高的剂量-效应关系（P<0.01）；同时，各实验组细胞IL-1β水平在24、48和72 h均呈随着染毒时间增加而上升的时间-效应关系（P<0.01）。NCI-H292细胞内IL-8水平在染毒剂量和染毒时间上有交互效应（P<0.01）： 在染毒72 h，BaP染毒剂量为0~16 μmol/L时IL-8水平呈随着染毒剂量升高而升高的剂量-效应关系（P<0.01）；4、8 μmol/L染毒组细胞IL-8水平在24、48和72 h呈随着染毒时间增加而上升的时间-效应关系（P<0.01）。结论 BaP染毒可引起NCI-H292细胞的存活率下降，且随着染毒剂量增加毒性作用增强；BaP可刺激NCI-H292细胞分泌IL-1β和IL-8，其可能在BaP致肺肿瘤炎症过程中发挥重要作用。     

铅致小鼠睾丸DNA损伤与细胞增殖

目的研究慢性铅染毒对小鼠睾丸细胞毒性机制。方法应用单细胞凝胶电泳技术（SCGE），检测铅对雄性小鼠生殖细胞DNA损伤，四甲基偶氮噻唑蓝（MTT）实验检测睾丸细胞增殖功能，生化试剂检测细胞脂质过氧化损伤。结果从低剂量组到高剂量组铅均可引起睾丸生殖细胞DNA不同程度损伤；低（0．15％）、中（0．3％）、高（0．6％）DNA迁移长度及迁移率与对照组之间差异有统计学意义（P〈0．01）；中、高浓度铅具有抑制睾丸细胞增殖的作用，使睾丸丙二醛（MDA）升高、超氧化物歧化酶（SOD）、谷胱苷肽过氧化物酶（GSH-Px）活性降低。结论铅可致睾丸细胞脂质过氧化损伤，导致DNA链断裂损伤，且具有抑制睾丸细胞增殖作用。     

广州市市售葡萄酒甲醇、杂醇油、铁、铜分析与质量控制的探讨

目的：了解市售葡萄酒甲醇、杂醇油、铁、铜的含量情况，探讨影响葡萄酒质量的主要因素，提出控制国产葡萄酒质量的技术措施。方法：通过气相色谱法、原子吸收分光光度法对广州市市售的150种国产全汁葡萄酒和50种进口全汁葡萄酒进行甲醇、杂醇油、铁、铜分析，比较国产与进口葡萄酒不同档次的甲醇、杂醇油、铁、铜含量情况。结果：国产葡萄酒中甲醇、杂醇油、铜、铁含量随着档次降低而显著升高（P〈0．01），合格率随着档次的下降而显著降低（P〈0．05），国产比进口同档次葡萄酒的甲醇含量显著升高（P〈0．05），国产中档葡萄酒比进口中档葡萄酒的铁含量显著升高（P〈0．05），国产中档葡萄酒铜、铁合格率比进口中档明显降低（P〈0．05）。结论：国产中、低档葡萄酒中甲醇、杂醇油、铁、铜含量偏高，合格率偏低。     

催化吸光光度法测定人发中铁的研究

Ｆｅ（Ⅲ）在稀硫酸介质中，能催化过氧化氢氧化甲基红的褪色反应〔１〕。本文采取固定时间、恒定水浴温度，非催化反应和催化反应溶液的吸光值之差ΔＡ（Ａ０－Ａ）与Ｆｅ（Ⅲ）浓度在０～０４μｇ／２５ｍｌ范围内呈良好的线性关系，由此可建立测定生物样品中微量铁的新方法。本法的灵敏度为２．０×１０－１１ｇ／ｍｌ     

甲基维生素B_（12）、维生素B_（12）降低甲基汞含量及免疫与行为毒性作用的研究

研究发现２．０～３．０ｍｇ／ｋｇ甲基维生素Ｂ_（１２）、维生素Ｂ_（１２）均可使孕鼠脑、肝、肾中甲基汞含量明显低于甲基汞组，而对胎仔脑及胎盘中甲基汞含量有明显减少。甲基维生素Ｂ_（１２）、维生素Ｂ_（１２）并可增强机体特异性细胞免疫功能与机体非特异性免疫功能，可改善动物多种行为不良作用。     

氟硒镉致大鼠睾丸脂质过氧化及微量元素变化

目的 探讨氟硒镉对大鼠睾丸脂质过氧化及微量元素变化的影响。方法 将氟硒镉经饮水染毒大鼠，10周后检测睾丸中脂质过氧化物（LPO）和谷胱甘肽过氧化物酶（GSH—Px）及镉硒锌铁的含量。结果 与对照组比较，氟、镉组LPO含量明显增高，GSH—Px显著降低，硒组没有明显改变。任意二联及三联时LPO含量较氟硒镉单独组明显降低，GSH—Px明显增高。各实验组硒无明显变化，氟组的镉硒锌铁也无明显改变，镉组的镉、铁显著增高，硒组、氟硒组的锌、铁显著增高，镉硒、氟镉以及氯硒镉组的镉、铁里明显升高。结论 氟、镉可引起大鼠睾丸脂质过氧化作用增强。抗氧化酶活性降低，硒的影响甚微。当三者任意二联时可降低脂质过氧化作用，三联时作用更强。硒可降低镉在睾丸中的蓄积，同时提高硒、锌水平，氟硒镉均可引起睾丸中铁水平升高，并有协同作用。     

铅作业男工血中某些生殖激素水平的研究

本文对４８名铅作业男工血铅（ＰｂＢ）、精铅（ＰｂＳ）、血清黄体生成素（ＬＨ）、血清卵泡刺激素（ＦＳＨ）、血浆睾丸酮水平及其相互关系进行了研究，结果发现血铅、精铅明显高于对照组（Ｐ＜０．０５）；血清ＬＨ明显高于对照组（Ｐ＜０．０５）；ＦＳＨ、血浆睾丸酮含量明显低于对照组（Ｐ＜０．０５）；血铅高浓度组血清ＬＨ明显高于血铅低浓度组（Ｐ＜０．０１）；而ＦＳＨ、Ｔ明显降低（Ｐ＜０．０５）；精铅高浓度组ＬＨ明显高于精铅低浓度组（Ｐ＜０．０１），而Ｔ明显低于精铅低浓度组（Ｐ＜０．０５）；提示铅可损伤下丘脑－垂体－睾丸轴的正常生理功能；铅影响男性某些性激素的分泌功能可能是铅中毒的重要机制之一。     

Saliva cotinine levels in smokers and nonsmokers

The authors collected by mail self-reported data on smoking habits and saliva samples that were analyzed for cotinine concentration in 222 smokers and 97 nonsmokers. Participants were members of the University of Geneva (Switzerland) in 1995. The 207 cigarette-only smokers smoked on average 10.7 cigarettes/day and had a median concentration of cotinine of 113 ng/ml. The cotinine concentration was moderately associated with the number of cigarettes smoked per day (+14 ng/ml per additional cigarette, p < 0.001, R2 = 0.45) and was 54 ng/ml higher in men than in women after adjustment for cigarettes per day and for the Fagerstr?m Test for Nicotine Dependence. The cotinine level was not associated with the nicotine yield of cigarettes (r= 0.08). In nonsmokers, the median concentration of cotinine was 2.4 ng/ml. The cotinine concentration was 1.5 times higher in nonsmokers whose close friends/spouses were smokers than in nonsmokers whose close friends/spouses were nonsmokers (p = 0.05). A cutoff of 7 ng/ml of cotinine distinguished smokers from nonsmokers with a sensitivity of 92.3% and a specificity of 89.7%; a cutoff of 13 ng/ml provided equally satisfactory results (sensitivity, 86.5%; specificity, 95.9%). This study provides evidence for the construct validity of both questionnaires and saliva cotinine for the assessment of active and passive exposure to tobacco smoke.     

妊娠期脂质过氧化作用与围产儿预后的关系

目的 探讨脂质过氧化(LPO)作用与围产儿预后的关系。方法 选择正常晚期妊娠妇女102例和妊娠期肝内胆汁瘀积症(ICP)患者126例。分别测定LPO和红细胞超氧化物歧化酶(RBC-SOD)活性;比较新生儿出生体重、Apgar评分和羊水状况。结果 ICP组母血LPO和RBC-SOD均明显高于对照组,二者呈显著正相关。在ICP组,宫内生长受限(IUGR)、新生儿窒息和羊水异常时,脐血LPO浓度均明显增高,而脐血RBC-SOD活性均明显下降。脐血LPO与新生儿出生体重和Apagr评分呈明显负相关。结论 LPO与ICP围产儿不良预后密切相关。     

Determinants of salivary cotinine concentrations in Chinese male smokers

BACKGROUND: Identifying factors that affect cotinine levels in smokers may be useful for smoking cessation programs. Our aims were to characterize the distribution of salivary cotinine levels in Chinese smokers and to investigate factors that influence cotinine concentrations. METHODS: In a cross-sectional study, 600 Chinese adult smokers answered a questionnaire on smoking habits and provided a saliva sample for cotinine analysis. Modification of the relation between number of cigarettes smoked and cotinine concentration by individual characteristics, smoking behavior, and type of tobacco was evaluated. RESULTS: Quadratic model provided the best fit for the relation between number of cigarettes smoked in the previous 24 hours and salivary cotinine concentration. Among those smoking up to 20 cigarettes, the median cotinine concentration was higher among younger subjects, those smoking cigarettes without filter and regular rather than light cigarettes, and those inhaling frequently and deeply. Such trends were not observed among heavier smokers. The increase in cotinine per cigarette tended to be larger in those with lower median cotinine level. CONCLUSIONS: Our findings show that smoking behavior-related factors modify the relation between number of cigarettes smoked and salivary cotinine concentration. This suggests that smokers may regulate their smoking behavior to achieve a certain optimum nicotine level.     

Measures of maternal tobacco exposure and infant birth weight at term

This study was undertaken to determine the relation between self-reported number of cigarettes smoked per day and urine cotinine concentration during pregnancy and to examine the relations between these two measures of tobacco exposure and birth weight. Data were obtained from the Smoking Cessation in Pregnancy project, conducted between 1987 and 1991. Cigarette smoking information and urine cotinine concentration were collected for 3,395 self-reported smokers who were receiving prenatal care at public clinics in three US states (Colorado, Maryland, and Missouri) and who delivered term infants. General linear models were used to quantify urine cotinine variability explained by the number of cigarettes smoked per day and to generate mean adjusted birth weights for women with different levels of tobacco exposure. Self-reported number of cigarettes smoked per day explained only 13.9% of the variability in urine cotinine concentration. Birth weight declined as tobacco exposure increased; however, the relation was not linear. The sharpest declines in birth weight occurred at low levels of exposure. Furthermore, urine cotinine concentration did not explain more variability in birth weight than did number of cigarettes smoked. These findings should be considered by researchers studying the effects of smoking reduction on birth outcomes.     

Association of self-reported passive smoking in pregnant women with cotinine level of maternal urine and umbilical cord blood at delivery

Passive smoking during pregnancy leads to adverse effects on mother and infant. The present investigation was designed to evaluate the association between maternal reported passive smoking with the cotinine concentration of maternal urine and umbilical cord blood at delivery and to determine the accuracy of maternal reporting of exposure to cigarette smoke during pregnancy. This was a cross-sectional study. From the 108 non-smoker pregnant women who were referred for delivery, 54 were passive smokers. Urine samples were collected from the mothers in the delivery room and blood samples after birth were taken from the umbilical cord. Passive smoking was evaluated through questionnaire and cotinine level of urine and umbilical cord blood. The geometric mean cotinine concentration of the maternal urine and the umbilical cord serum were, respectively, 27.4 ± 29.96 ng/mL and 3.71 ± 1.22 ng/mL in the exposed group (P < 0.001) and 0.75 ± 2.29 and 0.40 ± 0.63 in the non-exposed group (P < 0.001). There was a statistically significant correlation between maternal urinary and umbilical cord serum level of cotinine (P < 0.001, r = 0.58). Significant associations were shown between maternal reports of exposure to cigarette smoking with cotinine level of urine (kappa = 96%) and umbilical cord (kappa = 98%) (P < 0.001). This study shows that the pregnant woman's report of passive smoking during pregnancy in Iran is accurate. The questionnaire is an appropriate method to evaluate smoke exposure and could replace cotinine measurement.     

Saliva cotinine and recent smoking--evidence for a nonlinear relationship.

Cotinine concentration in various body fluids is considered to be among the most useful markers of nicotine exposure currently available. Despite the prevailing consensus concerning cotinine''s usefulness, cotinine''s large intrasubject variability has led some to question the value of a single-point measurement. Several individual differences (for example, age, race, sex, and so forth) may affect cotinine excretion, and a peculiar nonlinearity between the number of cigarettes smoked and cotinine concentration has been reported previously in the literature. The purpose of this investigation was to examine the nature of the association between cotinine and reported number of cigarettes smoked after adjustment for the relationship between cotinine and age, a key individual difference known to affect drug absorption, distribution, metabolism, excretion, and tissue sensitivity. The authors examined the relationship between saliva cotinine and daily cigarette consumption in 116 smokers (mean age = 37.4 years; average number of cigarettes smoked daily = 20.1) who logged each cigarette into a hand-held computer as part of a study on the accuracy of recall. The Pearson correlation between saliva cotinine and the logged number of cigarettes smoked in the previous 17 hours (the time window corresponding to the half-life of cotinine) accounted for significantly more of the variance in cotinine than did the average logged number of cigarettes smoked daily during 5 days. Age was also significantly associated with cotinine levels. Further examination of the relationship between cotinine and amount smoked in the previous 17 hours revealed evidence for a significant nonlinear component.(ABSTRACT TRUNCATED AT 250 WORDS)     

Urinary cotinine as a marker for passive tobacco smoking

To provide an objective measure of the hazard smoking parents represent to their children's health, continue concentration in urine was measured by the colorimetric method using barbituric acid (DBA). A total of 205 children, aged 10-12, were examined. The results of laboratory tests were correlated with the data collected by interview. A significant difference in the average value of cotinine concentration was demonstrated between the children whose parents did not smoke (3.2 mumol/L) and those whose one parent smoked (5.8 mumol/L). An even larger concentration was recorded when both parents smoked (7.8 mumol/L). The largest cotinine concentration was determined in the urine of children--passive smokers whose both parents smoked and who did not have a room of their own (9.2 mumol/L). The difference in cotinine concentration between girls and boys was not statistically significant.     

Secondhand Smoke Exposure and Urine Cotinine Concentrations by Occupation among Korean Workers: Results from the 2008 Korea National Survey for Environmental Pollutants in the Human Body

This study aimed to estimate the status of secondhand smoke (SHS) exposure through urine cotinine analysis among nonsmoking workers in Korea and to analyze factors affecting urine cotinine concentrations. Data were based on “The 2008 Korea National Survey for Environmental Pollutants in the Human Body,” a cross-sectional study of the National Institute of Environmental Research of Korea. We selected 1448 nonsmoking adult workers from 200 localities to participate in this survey. Urine cotinine concentrations were analyzed using a gas chromatograph-mass selective detector. We calculated separate covariate-adjusted geometric means for socio-demographic variables for males, females, and total subjects by analysis of covariance (ANCOVA). Statistical analyses were performed using SPSS version 18.0 (SPSS Inc., Chicago, Ill.). The prevalence of self-reported exposure to SHS was 36.9%. The geometric mean (95% confidence interval) of urine cotinine concentrations among all participants was 16.50 (14.48–18.80) μg/L. Gender, living area, education, and SHS exposure showed significant differences in urine cotinine concentrations. The urine cotinine concentrations of farmworkers and blue-collar workers such as skilled agricultural, forestry, and fishery workers, and elementary occupations were higher than those of white-collar workers such as clerical support workers, technicians, and associate professionals. Such a high proportion of the population having high urine cotinine levels indicates widespread exposure to SHS among nonsmoking workers in Korea. Furthermore, the urine cotinine levels among nonsmoking workers exposed to SHS varied by occupation. The measured urine cotinine concentration is suggested to be a valuable indication of SHS exposure in Korea.     

Stages of change, smoking characteristics, and cotinine concentrations in smokers: setting priorities for smoking cessation

ObjectiveWe assessed whether the salivary cotinine content of daily smokers varied with the readiness to quit and smoking characteristics.MethodsThis cross-sectional study was conducted in Barcelona, Spain (n = 1245) in 2004–2005. We administered a questionnaire to assess smoking behaviour and collected saliva to determine the cotinine content. We determined the distribution of 278 adult daily smokers across different stages of change and categorised them by individual and smoking characteristics. We used medians and interquartile ranges (IQR) to relate cotinine concentrations to different stages of change, tobacco consumption, and nicotine dependence based on the Fagerström Test for Nicotine Dependence (FTND).ResultsAround 68%, 22%, and 11% of smokers were in precontemplation, contemplation, and preparation stages, respectively. A mean of 17.0 cigarettes was smoked daily, with no differences among stages of change. The median cotinine concentration was 151.3 ng/ml (IQR: 83.2–227.8 ng/ml), with no differences among stages of change. The cigarette consumption scores, FTND, and time to first cigarette of the day were positively associated with cotinine concentration.ConclusionsThe cotinine concentration was similar among the stages of change, but varied within each stage according to the number of cigarettes smoked, time to first cigarette of the day, and nicotine dependence.     

Estimating Cotinine Associations and a Saliva Cotinine Level to Identify Active Cigarette Smoking in Alaska Native Pregnant Women

Studies indicate nicotine metabolism varies by race and can change during pregnancy. Given high rates of tobacco use and limited studies among Alaska Native (AN) women, we estimated associations of saliva cotinine levels with cigarette use and second-hand smoke (SHS) exposure and estimated a saliva cotinine cutoff to distinguish smoking from non-smoking pregnant AN women. Using questionnaire data and saliva cotinine, we utilized multi-variable linear regression (n = 370) to estimate cotinine associations with tobacco use, SHS exposure, demographic, and pregnancy-related factors. Additionally, we estimated an optimal saliva cotinine cutoff for indication of active cigarette use in AN pregnant women using receiver operating characteristic (ROC) curve analysis (n = 377). Saliva cotinine significantly decreased with maternal age and significantly increased with cigarettes smoked per day, SHS exposure, and number of previous full term pregnancies. Using self-reported cigarette use in the past 7 days as indication of active smoking, the area under the ROC curve was 0.975 (95 % CI: 0.960–0.990). The point closest to 100 % specificity and sensitivity occurred with a cotinine concentration of 1.07 ng/mL, which corresponded to sensitivity of 94 % and specificity of 94 %. We recommend using a saliva cotinine cutoff of 1 ng/mL to distinguish active smoking in pregnant AN women. This cutoff is lower than used in other studies with pregnant women, most likely due to high prevalence of light or intermittent smoking in the AN population. Continued study of cotinine levels in diverse populations is needed.