The levels of neurotransmitters and receptors in brain tissue of aborted fetuses from areas of endemic fluorosis were tested. The results showed that in 10 fetuses from a high fluoride area ranging in age from 5 to 7 months, the levels of norepinephrine, 5-hydroxytryptamine, and alpha(1)-receptor were lower, and the level of epinephrine was higher as compared with levels seen in the control fetuses from a non-endemic fluorosis area; each of these differences was statistically significant (p < 0.05). Other monoamine neurotransmitters and metabolic products, such as dopamine, 5-hydroxyindoleacetic acid and 3,4-dihydroxybenzoic acid, showed nonsignificant differences (p > 0.05). The results suggest that the accumulation of fluoride in the brain tissue can disrupt the synthesis of certain neurotransmitters and receptors in nerve cells, leading to neural dysplasia or other damage.

目的研究慢性氟中毒大鼠肾脏自由基含量与形态学变化的关系.方法 Wistar大鼠随机分为三组.正常对照组,未作任何处理;染氟组,自由饮用含氟化钠132.6mg/L的含氟水;抗氧化中药-染氟组,自由饮用含氟化钠132.6mg/L的含氟水,同时每日经腹腔内注射抗氧化中药丹参绞股蓝复方3.125毫克/公斤/天,实验6个月时检查动物.用电子自旋共振的方法检测肾组织内自由基的含量,并观察肾脏的形态学变化.结果与正常对照组动物相比,染氟组自由基明显升高,电镜下见肾小管上皮细胞有巨大线粒体及髓鞘样结构形成,内质网扩张,粗面内质网上核糖体脱落,细胞浆内游离核糖体增加,胞核内异染色质有向核膜下聚集的趋势;光镜下呈颗粒性变,偶见坏死.抗氧化中药一染氟组肾组织中自由基含量不增高,光镜及电镜下均未见明显病变.结论慢性氟中毒时肾脏病变与自由基含量增多有密切关系.

Objective　To study the correlation between the free radicals and kidney injury in chronic fluorosis.Methods　30 Wistar rats were divided into three groups at random.Normal control group,drinking water containing sodium fluoride less than 1 mg/L.Fluoride exposed group,drinking water containing sodium fluoride,60 mg/ L.Antioxidant-fluoride exposed group,drinking water containing sodium fluoride, 60 mg/L,meanwhile daily intra-abdominal injection of Danshen-Gypenosides compo und,3.125 mg/kg.The animals were examined by the sixth month.Results　As compared with the normal controls,the fluori de exposed rats showed higher levels of free radicals and MDA,lower activity of SOD and GSH-Px in the blood and kidney tissues.The kidneys showed swelling of mitochondria and expansion of endoplasmic reticula.Whereas,the antioxidant herbs treated group showed no abnormal change.Conclusions　The fact indicated that kidney injury was closely correlated to free radicals.

Objective It was reported that a few cases of oral lichen planus (OLP) eventually developed into squamous cell carcinomas (SCC) and that mutanted P53 correlated closely with the malignant development of hyperplastic lesion of the oropharyngeal mucosa such as leukoplakia and OLP. In the present study, the malignant potential of OLP was detected by P53 protein expression and cell morphometry, compared with dysplastic leukoplakia (LK) and SCC. Methods Specimens of 28 cases of OLP were immunostained with monoclonal anti P53 by SABC method. Cell morphometric parameters were measured and analyzed in 16 of OLP specimens, normal buccal mucosa. LK and SCC serving as the controls. Results ① Prominent P53 protein expression was seen in 46.43% of OLP, 54.55% of LK and 60% of SCC biopsies. but negative in normal buccal mucosa. ② Cell morphometric parameters of OLP were compared with those of normal buccal mucosa, LK and SCC. The difference between SCC and OLP group was significant. Conclusion OLP has been found to be a benign lesion, exerting certain malignant potential, perhaps slighter than LK.

Objective To study the influence of experimental fluorosis on fatty acid composition of phospholipid in rat liver and kidney.Methods Wistar rats were fed with various amounts of fluoride in drinking water for seven months to produce the animal model with chronic fluorosis.Phospholipid in rat liver and kidney was extracted by the improved Falch method and fatty acid compositions of this lipid were analysed using gas chromatography.Results The results showed that all animals fed with high amount of fluoride suffered from chronic fluorosis,which manifested with dental fluorosis,the increase of fluoride level in urine,and the decrease of protein content in liver and kidney as compared to controls.The abnormal composition of fatty acids from phospholipids in liver and kidney was observed in the rats with chronic fluorosis.The proportion of unsaturated fatty acids was decreased and the saturated fatty acids increased.The species of unsaturated fatty acids influenced by fluorosis were 20:4 (arachidolic acid) and 22:6.Conclusions The study suggests that high amount of fluoride can induce modification of fatty acid compositions of phospholipid in liver and kidney,which might be the result from oxidative stress and the increased level of lipid peroxidation. [

目的研究慢性氟中毒时大脑损伤程度与染氟时间有无相关关系.方法实验用SD大鼠,分两组:正常组饮用普通自来水,实验组饮用氟水(48mg/L).于实验第3、6、12个月分枇处死动物,用电镜检查及体视学分析,观察大脑神经细胞线粒体等超微结构改变,并测脑氟及尿氟.结果脑氟蓄积量随染氟时间而增加,尿氟排除则不然,脑神经细胞线粒体等超微结构损伤程度随染氟时间、脑氟含量增加而加重,脑神经细胞线粒体平均周长(C)及体密度(Vv)与染氟时间之间有量效关系.结论慢性氟中毒时大脑损伤程度与染氟时间有关,二者间有一定量效关系.

An animal model of chronic fluorosis was produced by subjecting Wistar rats to high doses of fluoride in drinking water for a prolonged period. Phospholipid and neutral lipid contents in rat kidney were then analyzed by high-performance liquid chromatography (HPLC), and fatty acid compositions from individual phospholipids were measured by gas chromatography. Lipid peroxidation was detected by the thiobarbituric-acid-reactive substance assay. Results showed that the total phospholipid content significantly decreased in the kidney of the rats treated with high doses of fluoride and the main species influenced were phosphatidylethanolamine (PE) and phosphatidylcholine (PC). Decreased proportions of polyunsaturated fatty acids were observed in PE and PC in kidney of fluoride-treated animals compared to controls. No changes could be detected in the amounts of cholesterol and dolichol in kidneys between the rats treated with fluoride and controls. A significant decrease of ubiquinone in rat kidney was observed in the groups treated with excessive fluoride. High levels of lipid peroxidation were detected in kidney of the rats with fluorosis. It is plausible that the specific modification of lipid composition results from lipid peroxidation. The oxidative stress and modification of cellular membrane lipids may be involved in the pathogenesis of chronic fluorosis and provide a possible explanation for the gross system damage observed in the body, especially in soft tissues and organs.

Chronic fluorosis can severely damage many systems of human body, but its pathogenesis is unclear. Normal composition and structure of cellular membrane lipids are a basic factor to maintain cell function. In this investigation, cellular membrane lipids of the liver were analysed after a long term fluoride treatment for rats and the results are discussed in order to give an explanation for the pathogenesis of this disease. Wistar rats were supplied with drinking water containing either 30 or 100 ppm fluoride (NaF) for seven months. Contents of phospholipid and neutral lipid in rat liver were analyzed by high-performance liquid chromatography, and fatty acid composition from individual phospholipids was measured by gas chromatography. Results showed that the total liver phospholipid content decreased in the rats treated with high dose of fluoride due to a lower content of phosphatidylethanolamine (PE), phosphatidylcholine (PC) and phosphatidylserine (PS). Among the fatty acid compositions of PE and PC in the livers of fluoride poisoned animals, the proportion of polyunsaturated fatty acids (20:4 and 22:6) decreased, whereas saturated fatty acids (16:0 and 18:0) increased. No changes could be detected in the amounts of liver cholesterol and dolichol. Total ubiquinone contents in rat liver were reduced by 11% in the group treated with 30 ppm fluoride and by 42% in the group treated with 100 ppm fluoride. In the subclasses of ubiquinone, both ubiquinone-9 and ubiquinoine-10 amounts decreased after fluoride treatment. These modifications of membrane lipids might be induced by oxidative stress, which might be an important factor in the pathogenesis of chronic fluorosis.

Brain membrane lipid in rats were analyzed after being fed either 30 or 100 ppm fluoride for 3, 5, and 7 months. The protein content of brain with fluorosis decreased, whereas the DNA content remained stable during the entire period of investigation. After 7 months of fluoride treatment, the total brain phospholipid content decreased by 10% and 20% in the 30 and 100 ppm fluoride groups, respectively. The main species of phospholipid influenced by fluorosis were phosphatidylethanolamine, phosphatidylcholine, and phosphatidylserine. The fatty acid and aldehyde compositions of individual phospholipid classes were unchanged. No modifications could be detected in the amounts of cholesterol and dolichol. After 3 months of fluoride treatment, ubiquinone contents in brain were lower; however, at 7 months they were obviously increased in both groups of fluoride treatment. The results demonstrate that the contents of phospholipid and ubiquinone are modified in brains affected by chronic fluorosis and these changes of membrane lipids could be involved in the pathogenesis of this disease.

对矽肺、矽肺合并肺癌、无矽肺的肺癌及对照组各３～４例的肺组织进行扫描电镜及能量色散Ｘ线分析（ＳＥＭ－ＥＤＸＡ）。ＳＥＭ观察发现，矽肺组及矽肺合并肺癌组病变处的胶原纤维之间有矽尘颗粒结晶。ＥＤＸＡ发现，矽肺组及矽肺合并肺癌组Ｓｉ的含量明显高于其他元素及另外两组Ｓｉ的含量（Ｐ＜０．０１），无矽肺的肺癌组及对照组Ｓｉ的含量则较Ａｌ、Ｐ、Ｓ为低。

The spectrum of trace elements was determined in 19 cases of colon carcinoma with analytical electron microscope. Besides, the quantities of trace elements in the cancerous tissue and the mucosa beyond the site of cancer were measured in 31 cases by flameless atomic absorption spectrophotometry. A reprocessing technique was applied to convert the paraffin sections directly to resin sections in order to recover the assessment of elements in these tissues. Fe, Al and macro elements Ca, S were recovered in 100% of the cases in both the cancer tissue and the mucosa taken beyond the site of cancer. The recovery rates of Ni and macro elements including K, Mg, P, Cl were 50%. The recovery rates of Si in poorly-differentiated adenocarcinoma were higher than that in the mucosa far from the cancer site. The levels of Cu, Zn and Ni in the cancerous tissue were lower than those detected in the mucosa (P < 0.01). No significant difference was noticed between the cancerous tissue and the mucosa beyond the site of cancer on Fe, Mn, Pb, Co and Cr contents.