Nonasbestos pulmonary mineral fibers in the general population

Total pulmonary nonasbestos mineral content was determined for a series of 20 patients who had no occupational dust exposure. To extract mineral fibers, lung tissue was dissolved in bleach and the treated sediment transferred to the electron microscope grid. Mineral fibers were identified using electron diffraction and energy dispersive x-ray spectroscopy. The mean number of nonasbestos fibers, 106 X 10(3)/g wet lung, was almost identical to the mean number of asbestos fibers, 102 X 10(3)/g. Thirteen different species or groups of nonasbestos minerals were found: apatite accounted for 18% of the total and talc for 16%. All other forms accounted for less than 8% each. Silica was found in every lung, and talc in 19 of 20 lungs. Of the fibers, 86% were shorter than 5 microns, and most of the fibers had aspect ratios less than 15. No correlations were seen between numbers or types of fibers and age, sex, or smoking. It is concluded that (1) substantial numbers of nonasbestos fibers are present in lungs of the general population. Most of these fibers are short and of low aspect ratio; and (2) by phase microscopy one is as likely to observe nonasbestos as asbestos fibers in these preparations, indicating that light microscopic methods are not suitable for this type of analysis. These data provide a baseline for comparison with patients believed to have a mineral fiber-related disease.     

Oxidative stress

Oxidative stress is defined by an imbalance between increased levels of reactive oxygen species (ROS) and a low activity of antioxidant mechanisms. An increased oxidative stress can induce damage to the cellular structure and potentially destroy tissues. However, ROS are needed for adequate cell function, including the production of energy by the mitochondria. Increased oxidative stress has been incriminated in physiological conditions, such as aging and exercise, and in several pathological conditions, including cancer, neurodegenerative diseases, cardiovascular diseases, diabetes, inflammatory diseases, and intoxications. However, prevention by antioxidants has been mostly inefficient. Therefore, a rigorous scientific evaluation in well-defined conditions is mandatory to define the appropriate place for manipulations of the oxidative pathways in human medicine.     

Environmental tobacco smoke exposure and pulmonary function among adults in NHANES III: impact on the general population and adults with current asthma

The impact of environmental tobacco smoke (ETS) exposure on adult pulmonary function has not been clearly determined. Because adults with asthma have chronic airway inflammation, they may be a particularly susceptible group. Using data from the Third National Health and Nutrition Examination Survey (NHANES III), I examined the cross-sectional relationship between serum cotinine, a biomarker of ETS exposure, and pulmonary function among 10,581 adult nonsmokers and 440 nonsmoking adults with asthma whose cotinine and spirometry data were available. I generated residuals, which are observed minus predicted values (based on Crapo equations), for forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio to adjust for age, sex, and height. In addition, I used multivariate linear regression to control for sociodemographic characteristics and previous smoking history. Most adults with and without asthma had detectable serum cotinine levels, indicating recent ETS exposure (85.7% and 83.4%, respectively). Among nonsmoking male participants, I found no evidence that ETS exposure was related to decreased pulmonary function. In the nonsmoking female stratum, the highest cotinine tertile was associated with a lower FEV1 [-100 mL; 95% confidence interval (CI), -143 to -56 mL], FVC (-119 mL; 95% CI, -168 to -69 mL), and FEV1/FVC ratio (-1.77%; 95% CI, -2.18% to -1.36%). Among women with asthma, the highest cotinine tertile was also associated with decreased FEV1 (-261 mL; 95% CI, -492 to -30 mL), FVC (-291 mL; 95% CI, -601 to 20 mL), and FEV1/FVC ratio (-1.6%; 95% CI, -3.3% to 0.19%). In conclusion, ETS exposure is associated with decreased pulmonary function in adult females, especially those with asthma. This analysis should provide further impetus for public policies that promote smoke-free environments.     

氧化作用与子宫内膜异位症

子宫内膜异位症是育龄妇女的常见疾病 ,近年来其发病率有上升趋势 ,研究认为EM发生发展与腹腔氧化作用有关。氧化作用是一种炎症反应 ,EM中巨噬细胞释放的氧化活性物 ,腹腔液中氧化低密度脂蛋白及其产物的增加 ,子宫内膜细胞氧化酶与抗氧化酶的异常表达 ,腹腔液中VitE的消耗 ,均说明EM与腹腔氧化作用有关。本文综述有关研究结果为用抗氧化剂和抗炎症制剂预防EM发生提供新的研究途径     

氧化应激与妊娠

氧化应激是指活性氧生成与抗氧化防御系统之间的不平衡状态。氧化应激可在活性氧生成超过抗氧化防御系统时或者在抗氧化剂活性降低时发生。近年来,氧化应激作为多种疾病的发病原因而备受关注。在产科,许多研究表明氧化应激和妊娠有关。     

线粒体与氧化损伤

线粒体不仅是细胞内物质和能量代谢的主要细胞器,也参与调控细胞内氧化还原水平。文章基于近期研究总结了细胞内各种氧化损伤,以及线粒体与这些氧化损伤的关系。     

Oxidative stress in glomerulonephritis

The aim of this review is to focus on the possible role of reactive oxygen species (ROS) in the pathogenesis of glomerulonephritis (GN) and to review the potential mechanisms of this ROS-mediated renal injury. This paper examines the literature which demonstrates ROS as primary mediators in GN, responsible for modifications of glomerular permeability to proteins, development of morphologic lesions and alteration of glomerular haemodynamics (reduction in glomerular blood flow and glomerular filtration rate). In glomeruli, ROS are generated by both infiltrating cells (neutrophils, monocytes) and resident glomerular cells (mesangial and endothelial cells and podocytes). The participation of ROS in glomerular damage was proved in many experimental studies by detection of products of oxidant injury in renal tissue or urine and by demonstration of a protective effect of antioxidants in those lesions.     

Oxidative stress and cognitive impairment in the elderly

Cognitive impairment is a major component of age-related dementing diseases and it has been suggested that it could share the same pathological pathways with neurodegenerative processes and cerebrovascular lesions. The free radical theory of aging could be one of these pathways. Observational studies of relationships between cognitive impairment and antioxidant status are based on the evaluation of dietary intake or on the levels of carotenoids, selenium and vitamins A, C and E in plasma. More convincing results were obtained on vitamin C and carotenoids. Despite some limitations, the comparison between results obtained in various populations is becoming increasingly informative and these studies argue for a protective effect of antioxidants on cognitive performance.     

Oxidative stress in porphyria and carriers

We sought to establish a causal relationship between oxidative stress and porphyria in patients and carriers. We reported changes in urinary porphyrin concentrations related to 8-hydroxy-2'-deoxyguanosine. METHODS: We measured urinary 8-hydroxy-2'-deoxyguanosine concentration in porphyria patients and carriers with multifactorial inheritance as a possible marker of attack. The porphyria types included 10 patients with porphyria cutanea tarda, 5 with variegate porphyria, 8 with hereditary coproporphyria, 7 with congenital erythropoietic porphyria, 5 with erythropoietic protoporphyria, 5 with acute intermittent porphyria, 7 erythropoietic protoporphyria carriers, and 7 acute intermittent porphyria carriers. RESULTS: Urinary porphyrin concentrations in these patients were significantly higher than those in healthy subjects (p<0.001). Urinary 8-hydroxy-2'-deoxyguanosine concentrations were significantly high in dermatopathy porphyria types namely porphyria cutanea tarda (p<0.001), variegate porphyria (p<0.05), hereditary coproporphyria (p<0.05), congenital erythropoietic phyria (p<0.05), and erythropoietic protoporphyria (p<0.001). CONCLUSION: These results reveal that urinary 8-hydroxy-2'-deoxyguanosine concentration in cutis porphyria types is a good predictor of attack and abatement.     

Lung function and health status in metropolitan fire-fighters compared to general population controls

Purpose  

To assess health status of South Australian (SA) metropolitan fire-fighters in terms of lung function and health-related quality of life, compare these with general population controls, and explore associations between fire-fighters’ self-reported occupational exposure and health status.     

常规肺通气功能测定在儿童哮喘诊治中的作用

目的 探讨常规肺功能检测在儿童哮喘诊断、治疗及疗效评价中的作用.方法 应用Master Screen系列肺功能测定系统,对40例不同病期哮喘患儿进行常规肺通气功能检测,因测定需要患儿配合,发作期患儿完成2l例,缓解期完成28例;选择发作期30例进行支气管舒张试验的患者肺功能资料进行研究.结果 常规肺通气功能测定发作期与缓解期结果比较,用力肺活量、1秒钟用力呼气量、1秒钟用力呼气量与用力肺活量比值、最大呼气流量、排出25%～75%肺活量后用力呼气量的差异有显著性(t=2.47～5.37,P＜0.01).发作期排出75%肺活量后用力呼气量总异常率达100.00%,缓解期排出75%肺活量后用力呼气量总异常率仍达53.57%,提示缓解期仍有小气道功能障碍.不同病期患儿肺功能测定结果用力肺活量、1秒钟用力呼气量、1秒钟用力呼气量与用力肺活量比值、最大呼气流量、排出25%肺活量后用力呼气量、排出50%肺活量后用力呼气量、排出75%肺活量后用力呼气量异常率的差异具有显著性(x2分别为45.23、34.71、lO.90、22.19、17.90、5.64、13.27,均P＜0.05).支气管舒张试验雾化吸入万托林后用力肺活量、1秒钟用力呼气量、1秒钟用力呼气量与用力肺活量比值、最大呼气流量、排出25%～75%肺活量后用力呼气量均明显增高(t=4.76～7.01,P＜0.01),表明雾化吸入万托林可迅速减低气道阻力,改善肺通气功能,进一步证明哮喘儿气道阻塞具有可逆性.结论 常规肺通气功能检测可用于儿童哮喘诊断及治疗. 力呼气量、排出75%肺活量后用力呼气量异常率的差异具有显著性(x2分别为45.23、34.71、lO.90、22.19、17.90、5.64、13.27,均P＜0.05).支气管舒张试验雾化吸入万托林后用力肺活量、 秒钟用力呼气量、1秒钟用力呼气量与用力肺活量比值、最大呼气流量、排出25%～75%肺活量后用力呼气量均明显增高(t=4.76～7.01,P＜0.01),表明雾化吸入万托林可迅速减低气道阻力,改善肺通气功能,进一步证明哮喘惠儿气道阻塞具有可逆性.结论 常规肺通气功能检测可用于儿童哮喘诊断及治疗. 力呼气量、排出75%肺活量后用力呼气量异常率的差异具有显著性(x2分别为45.23、34.71、lO.90、22.19、17.90、5.64、13.27,均P＜0.05).支气管舒张试验雾化吸入万托林后用力肺活量、 秒钟用力呼气量、1秒钟用力呼气量与用力肺活量比值、最大呼气流量、排出25%～75%肺活量后用力呼气量均明显增高(t=4.76～7.01,P＜0.01),表明雾化吸入万托林可迅速减低气道阻力,改善肺通气功能,进一步证明哮喘惠儿气道阻塞具有可逆性.结论 常     

Oxidative stress and liver disease

Several papers have been published on the important role of oxidative stress on living cells and cell responses e.g. apoptosis and necrosis, which leads to cell death. At the same time mild oxidative stress can modulate signal transduction cascades and redirect gene expression, and influence many cellular responses, e.g. proliferation, differentiation, reproduction. Regulations of the cell cycle depend on intracellular redox state. Critical steps in the signal transduction cascade are sensitive to oxidative stress and antioxidants. Heavy metal accumulation in higher concentration may inhibit enzyme activities influence the acute phase protein synthesis and gene expression, as well as the pro-oxidant and antioxidant forms of scavenger molecules. Polyphenols and flavonoid type antioxidants may influence the signal transduction routes as well. Ethanol inducible cytochrome P450 2EI isoenzyme oxidise ethanol and acetaldehyde and numerous potentially toxic xenobiotic and produce toxic oxygen free radicals, which are implicated in the pathogenesis of alcoholic liver diseases. Natural preparations, e.g. tea infusions contains trace elements and polyphenol type antioxidants in high concentration, therefore may influence the redox homeostasis, and especially dangerous with interaction of other medicines and alcohol.     

重症颅脑外伤患者肺部感染的氧化应激与TF和TFPI-1

目的探讨肺部感染对重症颅脑外伤患者氧化应激、组织因子(Tissue Factor,TF)、组织因子途径抑制物-1(Tissue factor pathway inhibitor-1,TFPI-1)的影响。方法选取2016年9月-2019年2月于山东省日照市中医医院住院治疗的156例重症颅脑外伤患者为研究对象,其中合并肺部感染的患者共计35例并设为感染组,未发生肺部感染的121例患者设为对照组。统计感染组患者病原学结果;测定并比较两组患者氧化应激(丙二醛(Malondialdehyde,MDA)、超氧化物歧化酶(Superoxide dismutase,SOD)以及过氧化氢酯(Catalase,CAT))、TF、TFPI-1、炎症因子指标水平变化。结果重症颅脑外伤伴肺部感染患者共检出病原菌41株,其中革兰阴性菌占65.85%(27/41),革兰阳性菌占26.83%(11/41),真菌占7.32%(3/41)。感染组患者MDA为(19.11±3.09)U/ml高于对照组,SOD和CAT为(17.68±2.89)U/L、(21.55±1.89)U/ml低于对照组(P<0.001)。感染组患者TF、TFPI-1分别为(47.09±9.08)ng/L、(40.95±8.16)μg/L高于对照组(P<0.001)。感染组患者IL-4、IL-6分别为(86.46.09±10.81)ng/L、(15.35±1.52)pg/ml高于对照组(P<0.001)。结论重症颅脑外伤肺部感染患者中的主要致病菌为革兰阴性菌,且肺部感染导致机体氧化应激状态紊乱,并能够对TF、TFPI-1水平变化造成不同程度的影响,而明确术后感染原因有利于患者预后效果的进一步提高。     

Oxidative stress and Alzheimer disease

Research in the field of molecular biology has helped to provide a better understanding of both the cascade of biochemical events that occurs with Alzheimer disease (AD) and the heterogeneous nature of the disease. One hypothesis that accounts for both the heterogeneous nature of AD and the fact that aging is the most obvious risk factor is that free radicals are involved. The probability of this involvement is supported by the fact that neurons are extremely sensitive to attacks by destructive free radicals. Furthermore, lesions are present in the brains of AD patients that are typically associated with attacks by free radicals (eg, damage to DNA, protein oxidation, lipid peroxidation, and advanced glycosylation end products), and metals (eg, iron, copper, zinc, and aluminum) are present that have catalytic activity that produce free radicals. beta-Amyloid is aggregated and produces more free radicals in the presence of free radicals; beta-amyloid toxicity is eliminated by free radical scavengers. Apolipoprotein E is subject to attacks by free radicals, and apolipoprotein E peroxidation has been correlated with AD. In contrast, apolipoprotein E can act as a free radical scavenger and this behavior is isoform dependent. AD has been linked to mitochondrial anomalies affecting cytochrome-c oxidase, and these anomalies may contribute to the abnormal production of free radicals. Finally, many free radical scavengers (eg, vitamin E, selegeline, and Ginkgo biloba extract EGb 761) have produced promising results in relation to AD, as has desferrioxamine-an iron-chelating agent-and antiinflammatory drugs and estrogens, which also have an antioxidant effect.     

Oxidative stress and Parkinson's disease

The etiology of Parkinson's disease (PD) is still unknown. Genetic factors and environmental exposure have been suggested in the etiopathogenesis of the disease. But the cause of dopaminergic cell loss in patients with PD remains unknown. During the last decade studies of the pathogenesis of PD have centred on the oxidative damage to the substantia nigra pars compacta. An increased free radical production and an inadequate antioxidant defence system have been reported, which could contribute to the biopathology of PD. The GSH levels in the brain are decreased, and iron levels in the substantia nigra are elevated. Moreover there are changes in SOD with an increased activity in the substantia nigra. The possible implication of oxidative stress in cell loss has encouraged research into the role of certain antioxidant agents, such as dietary compounds and drugs, as protective agents against PD.     

Oxidative stress and cognitive longevity

ObjectiveThe potential relation between metabolic activity within the central nervous system and retention of cognitive functioning capacity was assessed.MethodsA detailed literature review was conducted and summarized.ResultsA large body of scientific evidence describes the interactions among cognitive activity, oxidative stress, neurodegeneration, neuroprotection, cognitive aging, and retention of cognitive functioning ability.ConclusionMaintenance of redox balance within the central nervous system can forestall cognitive decline and promote cognitive longevity.     

Possible effects of environmental cadmium exposure on kidney function in the Japanese general population

Objectives: To examine whether the current level of environmental exposure to cadmium (Cd) is associated with kidney dysfunction among general populations in Japan. Methods: A nationwide survey was conducted in Japan from 1991 to 1997 at 30 survey sites (with no known environmental heavy metal pollution), by the collection of 24-h food-duplicate samples, peripheral blood specimens and morning spot urine samples. In practice, 607 non-smoking adult women provided these samples. After being wet-ashed, the samples were analyzed for Cd in food duplicates (Cd-F), in blood (Cd-B) and urine (Cd-U) by inductively-coupled plasma mass spectrometry (ICP-MS). Urine samples were also analyzed for α₁-microglobulin (α₁-MG), β₂-microglobulin (β₂-MG) and retinol-binding protein (RBP), creatinine (cr) and specific gravity. Possible tubular dysfunction in association with Cd exposure was examined by simple, multiple and logistic regression analyses, and comparison among three different Cd-dose groups. To minimize the confounding effects of aging, 367 women from 41 to 60 years old were selected and subjected to the same statistical analyses. Results: The analysis of a whole population of 607 women showed that α₁-MG and possibly β₂-MG increased as a function of Cd-F, Cd-B and Cd-U. When the analysis was repeated with the selected population of 367 women aged 41–60, the Cd dose-dependent changes in α₁-MG and β₂-MG became less evident. The distribution of the selected population with α₁-MG above two low cut-off values of >4.9 and >8.4 mg/g cr or with β₂-MG above the lowest cut-off value of >400 μg/g cr, was biased toward the group with higher Cd-Ucr, but such bias was not significant for both α₁-MG and β₂-MG when higher cut-off values were employed. No bias was detected with RBP. Logistic regression analysis with α₁-MG, β₂-MG and RBP (with cut-off values given above) in combination with age, Cd-F, Cd-B and Cd-Ucr gave essentially the same results. Conclusions: The evidence for kidney dysfunction was of borderline significance in the present study population for which geometric mean Cd-F, Cd-B and Cd-U were 24.7 μg/day, 1.76 μg/l, and 3.94 μg/g cr, respectively. The findings might suggest at the same time that the safety margin is small for the Japanese general population regarding environmental Cd exposure. Received: 26 February 1999 / Accepted: 24 July 1999