Airborne emissions at skin surfaces: a potential biological exposure index

 Dermal exposures of methanol were administered in a clinical study designed to compare several biological indicators. Four subjects were exposed in five exposure sessions of varying length. In each session, a sequence of measurements of methanol concentrations in blood, breath, and headspace samples of air at exposed and unexposed skin were collected before and after dermal exposures. Skin headspace samples, collected in gas sampling bags, were designed to reflect equilibrium skin: air partitioning. At exposed skin, headspace samples were highly elevated for at least 8 h following exposure, indicating the presence of a methanol reservoir in skin. After exposure, methanol concentrations at exposed skin showed a rapid initial decline, then a slower first-order decrease. Methanol concentrations were clearly detectable in headspace samples at unexposed skin. Substantial transfer from exposed skin occurred due to mechanical contact and washing. When transfer was restricted, surface concentrations at unexposed skin were similar to levels in breath and were strongly correlated to methanol concentrations in blood. While results are preliminary due to the small sample sizes and several unresolved experimental issues, the simple, rapid, and noninvasive skin headspace measurements appear useful as a biological exposure indicator that clearly shows the presence and site of a dermal exposure, and measurements at unexposed skin reflect concentrations in blood. Received: 14 March 1995/Accepted: 3 November 1995     

Biomonitoring of aromatic amines and alkylating agents by measuring hemoglobin adducts

Summary Analysis of hemoglobin adducts in blood samples is suitable for the biological monitoring of genotoxic chemicals. The method is specific because the compound to which the individual was exposed is identified. The sensitivity of the method depends on the analytical procedure applied, but is hardly limiting since large amounts of the protein can be obtained. The method provides not only information about the internal exposure to the environmental chemical, but also about the individual's capacity to generate ultimate genotoxic metabolites from it. Since macromolecular damage in blood cells is correlated to that in potential target tissues, this information is relevant to risk assessment, insofar as macromolecular damage produced by a specific chemical can be correlated with the development of tumors.     

Guidelines and recommendations for MR imaging safety and patient management III. Questionnaire for screening patients before MR procedures

The authors present the third installment of the guidelines and recommendations from the Safety Committee of the Society for Magnetic Resonance Imaging (now the Society of Magnetic Resonance) concerning various issues related to the safety and management of patients undergoing magnetic resonance (MR) procedures. This document was developed to provide standardized and consistent information for use by health practitioners involved in screening patients or other individuals for MR procedures.     

Comparison of self-reports and biological measures for alcohol, tobacco, and illicit drugs consumption in psychiatric inpatients

BACKGROUND: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures. METHODS: The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients' self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded. RESULTS: The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa=.47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa=.2), and 37% underreported when using the CDT+GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption. CONCLUSION: This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.     

rhTPO 对60Co 照射小鼠造血系统影响的研究

目的为了检测ＴＰＯ的体内活性及其对血小板减少的治疗作用，寻找用以治疗辐射及化学药物等所致骨髓损伤造成的血小板减少与缺乏，缓解临床上的出血症状，降低死亡率的一种新途径。方法本实验应用基因工程的方法重组了人的ＴＰＯ，取昆明种正常雄性，经一次５．０Ｇｙ６０Ｃｏγ射线全身照射小白鼠为动物模型，通过对外周血血象的观察，及小鼠骨髓造血祖细胞培养的检测，研究了ｒｈＴＰＯ在体内对６０Ｃｏ全身照射处理小鼠的造血系统的影响。结果实验表明，ｒｈＴＰＯ能够减轻照射对小鼠外周血血小板及骨髓造血祖细胞中巨核系祖细胞的影响，并有促进其早期恢复的作用，且这种作用是量效相关的。结论提示，ＴＰＯ是巨核细胞系统较特异的正调控因子，具有促进巨核细胞增殖发育和刺激血小板生成的作用，是临床治疗骨髓组织损伤引起的血小板减少和缺乏及贫血的有希望的生物治疗药物。     

Effect on fetal mouse development of exposure to MR imaging and gadopentetate dimeglumine

Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrifice and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed.     

Toluene in blood as a marker of choice for low-level exposure to toluene

The validity of two new biological exposure markers of toluene in blood (TOL-B) and toluene in urine (TOL-U) was examined in comparison with that of the traditional marker of hippuric acid in urine (HA-U) in 294 male workers exposed to toluene in workroom air (TOL-A), mostly at low levels. The exposure was such that the geometric mean for toluene was 2.3 ppm with a maximum of 132 ppm; the workers were also exposed to other solvents such as hexane, ethyl acetate, styrene, and methanol, but at lower levels. The chance of cutaneous absorption was remote. Higher correlation with TOL-A and better sensitivity in separating the exposed workers from the nonexposed subjects were taken as selection criteria. When workers exposed to TOL-A at lower concentrations (< 50 ppm, < 10 ppm, < 2 ppm, etc.) were selected and correlation with TOL-A was examined, TOL-B showed the largest correlation coefficient which was significant even at TOL-A of < 1 ppm, whereas correlation of HA-U was no longer significant when TOL-A was < 10 ppm. TOL-U was between the two extremes. The sensitivities of TOL-B and TOL-U were comparable; HA-U showed the lowest sensitivity. Thus, it was concluded that TOL-B is the indicator of choice for detecting toluene exposure at low levels.     

Chronic occupational exposure to organic solvents

Summary Twenty-two persons (20 men and 2 women) were examined for their external and internal exposure to the glycol ether 1-methoxypropan-2-ol (PGME) during the production, leak testing and mounting of brake-hoses. For the measurement of external exposure, personal air monitoring was the method of choice. Average concentrations of PGME of 82.2 mg/m³ (22.3 ppm), 68.6 mg/m³ (18.6 ppm) and 11.3 mg/m³ (3.1 ppm) were found in the air of the brakehose production, leak test and mounting areas, respectively. For the estimation of internal exposure to PGME, this glycol ether was measured in both urine and blood. The biological samples were taken post-shift. The highest internal exposure levels were found in the brakehose production section and in the leak test area. The average post-shift concentrations for PGME in workers in the brakehose production section were 4.6 mg/l in urine and 13.5 mg/l in blood; the corresponding figures for workers in the leak test area were 4.2 mg/l in urine and 11.0 mg/l in blood. In blood and urine samples of workers engaged in the mounting area, PGME levels were below the detection limits. The elimination kinetics of PGME were also studied in three highly exposed persons, and mean excretion half-lives of PGME of approximately 4.4 h were found. On the basis of our results we made a rough calculation of a future biological tolerance value: we would except that concentrations of 38-109 mg per litre of blood and 10–31 mg per litre of urine would correspond to the German MAK value for PGME (375 mg/m³).     

临床肿瘤用药的统计分析

[目的]了解肿瘤用药的消费现状及发展趋势，为临床合理用药提供依据。[方法]对本院1996年-2002年抗肿瘤药、生物反应调节剂和升白细胞药的用药情况进行统计分析，以药品的年消耗金额作统计。[结果]抗肿瘤药、生物反应调节剂和升白细胞药分别占全部药品年消耗总金额的24．24％～33．73％、15．80％～23．33％和5．86％～9．11％。[结论]抗肿瘤药、生物反应调节剂和升白细胞药是用于肿瘤治疗的主要药品，尤其是抗肿瘤天然药物有着广阔的应用前景。     

部分创面外用抗菌药物与成纤维细胞生长因子2、表皮生长因子、重组人生长激素对成纤维细胞生物学特性影响的实验研究

目的观察部分创面外用抗菌药物与成纤维细胞生长因子(FGF)2、表皮生长因子 (EGF)、重组人生长激素(rhGH)对成纤维细胞生物学特性的影响。方法体外培养成纤维细胞, 按所加药物不同分为对照组(常规培养)、丁胺卡那霉素(0．021、0．210、2．100 mg/L)组、庆大霉素(5、 50、500 mg/L)组、氯霉素(0．01、0．10、1．00 mg/L)组、磺胺米隆(5、10 g/L)组、FGF2(2 400 U/ml)组、 EGF(2 000 U/ml)组及rhGH(0．016、0．160、1．600 g/L)组。用噻唑蓝(MTT)法测定各组成纤维细胞增殖活性[吸光度(A)值],用流式细胞仪检测细胞周期,并于显微镜下观察细胞形态的变化。结果 (1)MTT法检测:与对照组A值0．455 3±0．021 7比较,各种剂量丁胺卡那霉素组、庆大霉素组、氯霉素组、磺胺米隆组成纤维细胞A值均明显降低(P<0．05或0．01),其中磺胺米隆(5、10 g/L)组降低最明显,分别为0．101 3±0．001 1、0．095 0±0．004 1(P<0．01)。FGF2组及0．016 g/L rhGH 组细胞A值明显高于对照组(P<0．05),而EGF组及0.160、1．600 g/L rhGH组A值与对照组接近 (P>0．05)。(2)细胞周期检测:对照组细胞增殖指数(PI)为(9．63±0．45)％,与之比较,0．210 mg/L丁胺卡那霉素组细胞PI值无明显变化(P>0．05),FGF2组、EGF组及0．016 g/L rhGH组PI值均明显升高,分别为(46．76±2．33)％、(42．30±1．41)％、(13．29±0．47)％(P<0．05或0．01)。 (3)形态学观察:对照组、EGF组及0．160、1．600 g/L rhGH组成纤维细胞数目较多,呈长条形或梭形, 轮廓不清,透明度高;丁胺卡那霉素组、庆大霉素组、氯霉素组、磺胺米隆组细胞数目较少,形态不规则,轮廓清晰,透明度低,细胞内多有颗粒样物质及空泡;FGF2组、0．016 g/L rhGH组细胞分布均匀、密集,呈长条形或梭形,核分裂相多见,轮廓不清,透明度高。结论不同创面外用药物对成纤维细胞生物学特性的影响各异,在创面修复过程中应选择合适的创面外用药物,以促进愈合并抑制瘢痕增生。