Impairment of neurobehavioral function and color vision loss among workers exposed to low concentration of styrene--a review of literatures

Recently many studies on the health effects of workers who exposed to low-concentration styrene have been published. In this paper firstly we mentioned the reasons why nervous system was critical organ for evaluating the toxicity of organic solvents both in the acute and chronic exposure phases. Then we indicated how neurobehavioral test batteries were useful to detect subclinical adverse health effects of workers exposed to organic solvents. Secondly we reviewed many epidemiological studies on the impairment of neurobehavioral function, i.e., perceptual speed, memory, cognition, personality and mood, and the loss of color vision among styrene workers. Finally, we showed our recent data on the relationship between color vision loss and the concentration of urine metabolites among styrene workers. It can conclude that styrene may cause damage on nervous system, even at the low exposure level such as 50 ppm which used to be the Threshold Limit Value (TLV) recommended by Japan Society for Occupational Health (until 1999) and American Conference of Industrial Hygienists (until 1997).     

Health care of workers engaged in waste water treatment. 1) The exposure conditions to organic solvents in workers engaged in waste water treatment

In the investigation of the exposure conditions to organic solvents of workers in 35 waste water treatment facilities, it was found that these workers treated various kinds of solvents. Almost all of the facilities treated chloroform, acetone, n-hexane, methanol and carbon tetrachloride. The average exposure concentration of the workers was, however, low. Exposure concentration to organic solvents (chloroform, xylene and carbon tetrachloride) was evaluated in one of the facilities. The average concentration of the respective solvents in the workers did not exceed the threshold limit value of Japan, but the concentration calculated on the basis of combined exposure exceeded the threshold limit value. On the other hand, high concentrations of organic solvents were detected in the room where the solvents were introduced but not in the working rooms, indicating that the workers engaged in waste water treatment were mainly exposed to organic solvents in the former room where they sorted and mixed the solvents and placed them in the incinerator. In conclusion, improvement in working conditions and health care for workers engaged in waste water treatment facilities should be made in order to prevent workers from becoming intoxicated by organic solvents.     

Influence of occupational exposure to organic solvents on kidney function

Exposure to nephrotoxic substances may cause renal tubular and glomerular dysfunction. The aim of the paper was to evaluate, based on literature reports, whether occupational exposure to organic solvents entails a risk of renal dysfunction. The results of the studies performed over the last twenty years are contradictory. In workers occupationally exposed to organic solvents, tubular, glomerular, or no effects were found. The lack of association between the renal effects and the intensity or duration of exposure was reported in most of the studies. It has been suggested that this can be attributed to an individual susceptibility. Available information points to a possibility of mild renal effects, but not to a serious influence on the kidney function at the current levels of occupational exposure to organic solvents. Biological monitoring of early effects can help identify individuals susceptible to nephrotoxicity of this group of chemicals.     

Follow-up of two patients with mesangial IgA glomerulonephritis exposed to cadmium and organic solvents

For several years we carried out a follow-up of two patients with IgA mesangial glomerulonephritis with antecedents of exposure to toxic substances (cadmium and organic solvents). The first case involved a 47 year old male who was diagnosed with mesangial IgA glomerulonephritis eight years ago; he had been working for twelve years as a solderer. He had used metal bars containing 25% cadmium as part of the soldering material. Very high levels of cadmium were detected in his blood and urine. The second case involved a 50 year male who was exposed to a wide number of organic dissolvents for 23 years. Three years ago he was diagnosed with a proliferative diffuse mesangial glomerulonephritis with IgA deposits; in spite of that, the patient continued working until one year ago, when was found to have a chronic stage 3 renal disease secondary to IgA nephropathy. Patients diagnosed with mesangial IgA glomerulonephritis should be kept apart from exposure to nephrotoxic substances.     

The Kidney in Lead Poisoning

Kidney damage due to lead is still an interesting problem of industrial toxicology. In spite of abundant literature data, much still remains to be explained. There are controversial opinions, not only on the type of renal lesions due to lead, but also on whether lead affects the kidney at all.

In this paper our clinical observations on the effect of lead upon the kidney in 53 patients suffering from lead poisoning are presented. In 44 patients (40 men and four women) lead poisoning was due to occupation, and in nine (five men and four women) to the use of lead-glazed pottery. The length of exposure varied from two months to 35 years. In all cases the diagnosis of lead poisoning was made clinically and confirmed by laboratory tests.

Permanent changes in the form of chronic nephropathy were observed in only two patients. These were the two cases in which exposure to lead was the longest and most intense. Twenty-three patients showed functional renal lesions tending to normalize. In addition to the cases of organic nephropathy, blood pressure was persistently raised in one further patient; in two patients a raised blood pressure was observed only in the acute stage of poisoning.

On the basis of these findings we consider that lead intoxication can cause renal lesions. These lesions are for the most part functional and temporary. In cases of long and severe exposure and repeated lead intoxication, organic renal lesions seem possible. The disturbances of renal function observed in this study may be ascribed to disordered intrarenal circulation, due to the spastic effect of lead on intrarenal blood vessels, and to a direct toxic or indirect hypoxic effect of lead on the tubules.

When investigating renal function, we have observed that the timing of individual tests is of paramount importance. Some lesions are subject to changes in the natural course of lead poisoning, and unless this is borne in mind, apparently contradictory results may be obtained.

     

普伐他汀在治疗慢性移植肾肾病的应用研究

目的探讨普伐他汀在治疗慢性移植肾肾病中的作用. 方法对38例慢性移植肾肾病在常规抗慢性排异基础上服用普伐他汀,观察患者肾功能指标以及测定尿蛋白和血浆内皮素的变化. 结果普伐他汀治疗组患者肾功能指标改善优于对照组(P＜0.05),且能够降低蛋白尿减少内皮素-1生成(P＜0.01). 结论普伐他汀能够延缓慢性移植肾肾病肾衰进展,保护肾功能.     

Early indicators of renal damage in workers exposed to organic solvents

In order to investigate the renal function, a cross-sectional study was carried out on four groups of workers significantly exposed to a mixture of alicyclic and aliphatic C5-C7 hydrocarbons, to styrene, to a mixture mostly composed of toluene and xylenes and to chlorinated hydrocarbons, respectively. The study involved 438 workers. Exposure was characterized by means of urinary metabolites, or by means of environmental measures, when biological indicators were not available. The renal function impairment indicators included total proteinuria, albuminuria and urinary excretion of muramidase (E.C. 3.2.1.17) and beta-glucuronidase (E.C. 3.2.1.31). The trend of these parameters provides some evidence of renal damage due to occupational exposure to organic solvents and suggests that the lesions are mild and tubular rather than glomerular.     

Renal disease and occupational exposure to organic solvents: a case referent approach.

Several recent studies have suggested that a relation may exist between exposure to occupational organic solvents and diseases of the kidney--particularly malignancy and glomerulonephritis. Two case referent studies were undertaken in the West Midlands to investigate these possibilities. In the case of renal cancer 54 live cases of biopsy proved adenocarcinoma of the kidney were compared with an equal number of community based healthy referents matched for age, sex, place of residence, and socioeconomic and ethnic grouping. For glomerulonephritis, 50 biopsy proved cases were matched in the same manner with 50 referents. Fourteen other patients were also reviewed who, on biopsy, proved not to have glomerulonephritis. For both sets of cases and their referents each individual was interviewed and a detailed account obtained of medical history and environmental exposures. Exposure to solvents was assessed independently and "blind" in a semiquantitative way by an experienced occupational hygienist. Past exposure was estimated for 10 different solvent types and 17 material types. No relation was found between exposure to solvents and renal cancer or glomerulonephritis. In the case of renal cancer the numbers studied only precluded a fourfold excess risk. For glomerulonephritis, the study, although methodologically superior to most other published studies and of similar size, was of similar power to the renal cancer investigation.     

Renal disease and occupational exposure to organic solvents: a case referent approach

Several recent studies have suggested that a relation may exist between exposure to occupational organic solvents and diseases of the kidney--particularly malignancy and glomerulonephritis. Two case referent studies were undertaken in the West Midlands to investigate these possibilities. In the case of renal cancer 54 live cases of biopsy proved adenocarcinoma of the kidney were compared with an equal number of community based healthy referents matched for age, sex, place of residence, and socioeconomic and ethnic grouping. For glomerulonephritis, 50 biopsy proved cases were matched in the same manner with 50 referents. Fourteen other patients were also reviewed who, on biopsy, proved not to have glomerulonephritis. For both sets of cases and their referents each individual was interviewed and a detailed account obtained of medical history and environmental exposures. Exposure to solvents was assessed independently and "blind" in a semiquantitative way by an experienced occupational hygienist. Past exposure was estimated for 10 different solvent types and 17 material types. No relation was found between exposure to solvents and renal cancer or glomerulonephritis. In the case of renal cancer the numbers studied only precluded a fourfold excess risk. For glomerulonephritis, the study, although methodologically superior to most other published studies and of similar size, was of similar power to the renal cancer investigation.     

原发性IgA肾病患儿肾组织免疫病理及CD44的表达

目的:探讨细胞表面糖蛋白(CD44)在儿童IgA肾病(IgAN)发病中的作用及其与肾小管间质损害的关系。方法:46例IgAN患儿按临床表现分为3组:孤立性血尿组14例,血尿蛋白尿组17例,肾病综合征组15例;按病理分级分为3组:病理Ⅰ+Ⅱ级组23例,Ⅲ级组14例,Ⅳ级组9例。设肾活检正常对照组4例。采用免疫组化SP法检测病例组与对照组肾组织CD44的表达,并分析其与肾小管间质病变程度的相关性。结果:①正常肾组织仅有少量CD44表达。②IgAN患儿肾组织中CD44的表达均较对照组明显增高,不同临床表现组中肾病综合征组最高,孤立性血尿组最低,且与IgAN患儿的病理分级密切相关。③IgAN患儿肾组织CD44的表达与肾小管间质损害程度呈正相关。结论:CD44参与了儿童IgAN的发病和肾小管间质损害,与IgAN的进展及预后有关。     

Membranous nephropathy following exposure to volatile hydrocarbons

Membranous nephropathy occurred in four male patients following exposure of 2, 11, 18, and 20 years, respectively, to various organic solvents. There was absorption through lungs and skin. It is impossible to identify the causative agent among the substantial number of solvents to which the individuals were exposed. There may be a causal relationship between membranous nephropathy and solvent exposure. Although the mechanism of production of membranous nephropathy in these cases is not known, an indirect immunological process mediated by endogenous tubular antigen is suggested. Exposed individuals may have proteinuria for long periods before onset of overt manifestations. Examination for proteinuria is a simple method of screening in these cases.     

Gender differences in risk of renal cell carcinoma and occupational exposures to chlorinated aliphatic hydrocarbons.

BACKGROUND: Organic solvents have been associated with renal cell cancer; however, the risk by gender and type of solvents is nuclear. METHODS: We evaluated the risk of renal cell carcinoma among men and women exposed to all organic solvents-combined, all chlorinated aliphatic hydrocarbons (CAHC)-combined, and nine individual CAHC using a priori job exposure matrices developed by NCI in a population-based case-control study in Minnesota, U.S. We interviewed 438 renal cell cancer cases (273 men and 165 women) and 687 controls (462 men and 225 women). RESULTS: Overall, 34% of male cases and 21% of female cases were exposed to organic solvents in general. The risk of renal cell carcinoma was significantly elevated among women exposed to all organic solvents combined (OR = 2.3; 95% CI = 1.3-4.2), to CAHC combined (OR = 2.1; 95% CI = 1.1-3.9), and to trichloroethylene (TCE) (OR = 2.0; 95% CI = 1.0-4.0). Among men, no significant excess risk was observed among men exposed to any of these nine individual CAHCs, all CAHCs-combined, or all organic solvents-combined. DISCUSSION: These observed gender differences in risk of renal cell carcinoma in relation to exposure to organic solvents may be explained by chance based on small numbers, or by the differences in body fat content, metabolic activity, the rate of elimination of xenobiotics from the body, or by differences in the level of exposure between men and women, even though they have the same job title.     

Endothelin and diabetic nephropathy: a new pathogenetic factor?

Endothelin is a vasoconstrictor and a mitogenic peptide. It is able in vivo as well as in vitro to affect renal function and structure. Experiments conducted on animal models have shown that diabetes mellitus is associated with an increase in urinary and plasma endothelin levels. This increase, is probably correlated to renal damage progression and to characteristic alterations in diabetic nephropathy. Also studies conducted on diabetic patients have demonstrated an increase in plasma endothelin. The role of endothelin should therefore be considered because it could be involved in the pathogenesis of diabetic nephropathy.     

Renal biopsy findings in diabetes mellitus

BACKGROUND: The prevalence of diabetic patients with endstage renal disease is increased overall the word. Renal biopsy is sometimes necessary to precise the type of renal damage. AIM: To precise the type and the frequency of non diabetic nephropathy in diabetic patients. METHODS: We enrolled retrospectively during 17 years, 72 diabetic patients who had a renal biopsy. RESULTS: A non diabetic nephropathy was found in 69.5 % of them. Its presence was correlate to the presence of hematuria and the absence of diabetic retinopathy. We can successfully treated nine patients with minimal-change nephrotic syndrome and one patient with crescentic glomerulonephritis. CONCLUSION: Renal biopsy must be done in diabetic patient with hematuria or in the absence of diabetic retinopathy.     

己酮可可碱对糖尿病肾病疗效的观察

目的　观察己酮可可碱对糖尿病肾病患者蛋白尿的治疗以预防肾功能损害的发生、发展。方法　观察３３ 例己酮可可碱治疗组及３６ 例对照组的２ 型糖尿病合并糖尿病肾病患者参试前后血粘度与尿系列微量蛋白、２４ 小时尿蛋白的变化。结果　己酮可可碱能降低糖尿病患者全血高切、低切粘度及血浆粘度，并降低尿系列微量蛋白、２４ 小时尿蛋白，经统计学处理治疗前后的两组数据具有显著性差异，且血粘度的下降与尿系列微量蛋白、２４小时尿蛋白的减少呈正相关。结论　己酮可可碱可降低２ 型糖尿病患者高血粘度状态，降低尿系列微量蛋白、２４小时尿蛋白，治疗糖尿病肾病，以预防肾功能衰竭的发生、发展     

8-异前列腺素F2α与高血压肾损害

目的 8-异前列腺素F2α（8-iso-prostaglandin F2α,8-iso-PGF2α）是细胞膜上的花生四烯酸在自由基的攻击下发生脂质过氧化,经非酶途径产生的前列腺素的衍生物。是评价氧化应激（oxiditive stress,OS）和脂质过氧化反应理想的生物学指标。肾脏是高血压靶器官损害的主要脏器之一,且高血压肾损害易与高血压形成恶性循环,是临床治疗的难点。8-异前列腺素F2a可以敏感地反映高血压肾损害时体内的OS水平,并进一步反映肾损害的严重程度。作者就8-iso-PGF2α与高血压肾损害的相关性研究进展作一综述。     

Organic solvent use in enterprises in Japan

This study was initiated to elucidate possible changes in types of organic solvents (to be called solvents in short) used in enterprises in Japan through comparison of current solvent types with historical data since 1983. To investigate current situation in solvent use in enterprises, surveys were conducted during one year of 2009 to 2010. In total, workroom air samples in 1,497 unit workplaces with solvent use were analyzed in accordance with regulatory requirements. Typical use pattern of solvents was as mixtures, accounting for >70% of cases. Adhesives spreading (followed by adhesion) was relatively common in small-scale enterprises, whereas printing and painting work was more common in middle-scale ones, and solvent use for testing and research purpose was basically in large-scaled enterprises. Through-out printing, painting, surface coating and adhesive application, toluene was most common (being detected in 49 to 82% of workplaces depending on work types), whereas isopropyl alcohol was most common (49%) in degreasing, cleaning and wiping workplaces. Other commonly used solvents were methyl alcohol, ethyl acetate and acetone (33 to 37%). Comparison with historical data in Japan and literature-retrieved data outside of Japan all agreed with the observation that toluene is the most commonly used solvent. Application of trichloroethylene and 1,1,1-trichloroethane, once common in 1980s, has ceased to exist in recent years.     

A study on the relative breakthrough time (RBT) of a respirator cartridge for forty-six kinds of organic solvent vapors

The breakthrough time of a commercially available respirator cartridge was measured for 46 kinds of organic solvents. The condition of the test air flow was set according to the Japanese government standard for the National Approval Test: at 300 ppm of an organic solvent vapor concentration, a temperature of 20 degrees C, a relative humidity of 50 percent, and a flow rate of 30 L/min. The interval between the start of passing the test flow through a cartridge and the time when the concentration of organic solvent vapors at the downstream of the cartridge reached 5 ppm was measured. The ratios of breakthrough times of organic solvents to that of cyclohexane which is designated as the standard test vapor in Japan, were calculated to obtain the relative breakthrough times (RBTs). Nine of the 46 organic solvents had breakthrough times shorter than that of cyclohexane, and these organic solvents with shorter RBTs were characterized by low boiling points and small molecular weights. The RBTs of 34 organic solvents were compared with the breakthrough times reported by Nelson et al. The relationship between the RBTs of this experiment and those reported by Nelson correlated well (correlation coefficient: 0.861).     

The Effects of Glomerular Endothelial Cell Autophagy on Diabetic Nephropathy

Diabetic nephropathy is one of the most common causes of end-stage renal disease worldwide and is associated with increased mortality in patients with type 1 and type 2 diabetes. Autophagy is a highly conserved"autophagy"pathway and is an important mechanism for maintaining glomerular and tubular homeostasis. Emerging evidence suggests that targeted autophagy pathway activation and restoration of autophagy activity may have renal protection. Glomerular endothelial cells are an important key factor in the development of diabetic nephropathy. Endothelial dysfunction is involved in the development of diabetic and non-diabetic glomerular injury and renal fibrosis. Evidence of glomerular endothelial dysfunction in the late stages of diabetic nephropathy, such as thrombotic microangiopathy,including impairment of glomerular capillary microaneurysms and glomerular membrane lysis autophagy, is related to the pathogenesis of diabetic nephropathy. Here, we mainly introduced the research progress of the effects of glomerular endothelial cell autophagy on diabetic nephropathy.     

Osteoporosis and renal dysfunction in a general population exposed to cadmium in China

Osteoporosis is a common metabolic disease characterized by low bone mass and microarchitectural deterioration of bone tissue. Many factors are involved in the occurrence of osteoporosis. Cadmium can cause both osteomalacia and osteoporosis and these effects have long been investigated through various epidemiological or experimental studies. The present study examines a possible relationship between cadmium nephropathy and its effects on the skeleton in populations living in a polluted area in southeast China. Monophoton absorptiometry was used to measure bone mineral density in the population and the Z score (the number of SD from the difference between the measured bone density of the individual and the group mean value for sex- and age-matched controls) was introduced to define osteoporosis (Z score < -2). Osteoporosis caused by cadmium exposure was demonstrated in this study on a general population environmentally exposed to cadmium in China. It was found that there were significant differences in the prevalence of osteoporosis among the different urinary cadmium groups (chi2 = 18.84, P = 0.0008). The linear trend test gave chi2 = 16.281, P = 0.00005. There was a dose-response relationship between cadmium exposure (urinary cadmium) and prevalence of osteoporosis. Of 31 subjects with osteoporosis, 23 subjects were suffering from renal dysfunction. The prevalence of renal dysfunction (74.19%) was significantly higher than that in those without osteoporosis (chi2 = 16.53, P < 0.001). Stratum analysis was performed to further assess the relationship between bone damage and renal impairment caused by cadmium. There was a significant difference between those with and without tubular damage (chi2 = 19.92, P = 0.000) but not in those with and without glomerular damage (chi2 = 0.08, P = 0.114). This showed that glomerular dysfunction plays a smaller role than tubular dysfunction in the causation of bone damage. It was found that the prevalence of osteoporosis increases with increasing values of parameters of tubular damage. Osteoporosis caused by cadmium is thus related to kidney dysfunction and especially to tubular damage and its severity but not to glomerular damage. The present study has thus demonstrated the combined adverse effects (osteoporosis and renal dysfunction) caused by environmental exposure to cadmium for the first time in Asia outside the endemic area in Japan.