Cognition Disorders ; chemically induced ; Humans ; Manganese ; toxicity ; Manganese Poisoning ; epidemiology

Long-term occupational exposure to manganese might cause manganese poisoning, which would had adverse effects on nervous system of workers. The basal nucleus was damaged and dopaminergic neuron was injuried by manganese. The mechanism could be related with interfering the energy metabolism of central nerve, changing neurotransmitters, activating oxidation system and so on. Genetic factors may also plays a significant role in the neurotoxicity caused by manganese. Study the effects of manganese exposure biomarker, the neurotoxicity of biomarkers and the genetic susceptibility to early and susceptibility biomarkers will contribute to the prevention and control of manganese neurotoxicity.
Biomarkers ; Disease Susceptibility ; Humans ; Manganese ; Manganese Poisoning ; Neurotoxicity Syndromes ; Occupational Exposure

Objective: To explore the changes of γ-GCS mRNA expression and GSH-PX in serum of workers exposed to manganese in order to provide scientific basis for early diagnosis of manganese poisoning. Methods: In June 2017, a total of 180 workers from a motorcycle manufacturer were selected by stratified random sampling, including 115 welders as the exposure group and 65 administrative office workers as the Control Group, the exposure group was divided into high exposure group (43 persons) and low exposure group (72 persons) according to whether the exposure group exceeded the standard limit. The levels of γ-gcs Mrna expression and GSH-Px activity in serum were determined by Occupational Health Survey, and the differences of γ-gcs Mrna expression and GSH-Px activity among different groups were analyzed. Results: Compared with the control group, the serum GSH-Px activity was lower and the serum γ-GCS mRNA expression level was higher in the exposed group (F=370.52, 275.95, P<0.01) . Compared with the control group, there was significant difference in γ-GCS mRNA expression level and GSH-Px activity (F=0.475、1.06, P<0.01; F=48.53、111.70, P<0.01) . The concentrations of manganese in air, welding dust and urine were positively correlated with the level of γ-GCS mRNA (r=0.71, 0.50, 0.31, P<0.01) The serum GSH-Px activity was negatively correlated with the concentrations of manganese in air, welding dust and urine (r=-0.80, -0.52, -0.30, P< 0.01) , There was no correlation between Serum γ-GSH-Px activity and age and years of exposure (P>0.05) . Conclusion: Serum γ-GCS mRNA expression level and GSH-Px activity level can be used as early biomarkers of manganese poisoning. The concentrations of manganese in workplace air, welding dust and urine manganese in workers are the influencing factors.
Air Pollutants, Occupational ; Dust ; Humans ; Ions ; Manganese ; Manganese Poisoning ; Occupational Exposure/analysis* ; RNA, Messenger/genetics* ; Welding

Adult ; Chronic Disease ; Electromyography ; Humans ; Magnetic Resonance Imaging ; Male ; Manganese Poisoning ; diagnosis ; Occupational Diseases ; diagnosis

Adult ; Aminosalicylic Acid ; therapeutic use ; Female ; Humans ; Manganese Poisoning ; drug therapy

Adult ; Aged ; Cohort Studies ; Dust ; analysis ; Female ; Humans ; Male ; Manganese ; analysis ; Manganese Poisoning ; diagnosis ; Middle Aged ; Occupational Exposure ; analysis ; Retrospective Studies ; Young Adult

OBJECTIVETo explore the biomarker of manganese exposure by analyzing the relationship between manganese exposure and concentration in some biomaterials.

METHODSThe air samples were collected through the individual air sample. According to the manganese levels in the air, workers were assigned to control group, low concentration group and high concentration group, and manganese in the hair, urine, serum, blood cell and saliva from different group were measured respectively. The correlations between concentration of external manganese exposure and manganese concentrations in biomaterials, and years of employment and concentrations in biomaterials were analyzed.

RESULTSIn the high concentration group, saliva manganese was 32.17 µg/L, hair manganese was 37.39 mg/kg, urine manganese was 2.50 µg/L, plasma manganese was 29.61 µg/L, blood manganese was 14.49 µg/L, were higher than those in the control group (10.40 µg/L, 1.60 mg/kg, 0.77 µg/L, 10.30 µg/L, 4.56 µg/L respectively) (P < 0.01). The manganese concentration in the saliva was significantly correlated with airborne manganese concentration (r = 0.649, P < 0.01), with the years of employment (r = 0.404, P < 0.01), with the total exposure of manganese (r = 0.342, P < 0.01), with the manganese concentration of plasma (r = 0.303, P < 0.01) and with the manganese concentration in blood cells (r = 0.359, P < 0.01), respectively.

CONCLUSIONSThe concentration of manganese in saliva could work as a biomarker of manganese internal exposure.

Adult ; Air Pollutants, Occupational ; analysis ; Biomarkers ; analysis ; Hair ; chemistry ; Humans ; Manganese ; analysis ; blood ; urine ; Manganese Poisoning ; prevention & control ; Middle Aged ; Occupational Exposure ; prevention & control ; Saliva ; chemistry ; Young Adult

OBJECTIVE: The accuracy of analytical results of blood and urine heavy metals came out to the main issue on occupational health from late eighties. The discrepancy of the results for same samples from different laboratories made the diagnosis for occupational diseases be unreliable. Therefore, a quality control program for analysis of samples taken from workplace had been introduced in Korea since 1992. This study aims to show the quality control program f'or analysis of blood and urine samples and its proficient rates from 1992 to 1999 and to know how they have been being used in occupational health. METHODS: The quality control program runs twice a year with mandatory items of blood lead and urine hippuvic acid and voluntary items of blood cadmium and manganese and urine mandellic acid and methyl hippuric acid. Participant laboratories are receiving three levels for each items and two out of three samples have to be qualified for being a proficient laboratory for the item. The acceptable range of blood lead and urine hippuric acid is +/-15% and that of the others is within 3 SD(standard deviation) from the reference values. RESULTS: The proficient rates of blood lead and urine hippuric acid was 89%, 90%, repectively, however those of the other voluntary items have been from 51% to 62%. The proficient rates of urine mercury and urine N-methylformamide(NMF), which are introduced since 1999, were very poor. Urine hippuric acid and blood lead were analyzed frequently for the purpose of biological monitoring conducting by special health examination organizations. Urine and blood manganese and urine metabolites of trichloroethylene, urine phenol, methylhippuric acid and cadmium were followed. CONCLUSIONS: In conclusion, the quality control program for biological monitoring has dramatically improve the ability of analysing blood and urine samples and eventually contributes to diagnose occupational diseases and to prevent occupational poisoning. However, some biological monitoring data, such as urine manganese, mercury and NMF, have been still reported from laboratories that were not accepted as a proficient laboratory.
Cadmium ; Diagnosis ; Environmental Monitoring ; Korea ; Manganese ; Metals, Heavy ; Occupational Diseases ; Occupational Health ; Phenol ; Poisoning ; Quality Control ; Reference Values ; Trichloroethylene

One of the most obvious effects of cadmium poisoning in experimental animals is induction of testicular necrosis. Many studies have been conducted, but the mechanism of the disturbance, which is peculiar to the testicle, has not been elucidated. Testicular damage due to cadmium exposure greatly differs depending upon strains of mice and methods of administration. As a preventive measure against testicular necrosis due to cadmium, pretreatment of small doses of cadmium and several kinds of metals have been found to be effective. In order to examine testicular damage by cadmium doses and protective effects by small doses of metals (Cd, Cu, Se, Mn) and phenobarbital which were administered before single challenge dose of cadmium, mature male I. C. R. mice, 16 weeks of age, weighing approximately 40g were used in this study. The weights of the body and the testicle, cadmium concentration in the testicle and results of histopathological findings of the experimental groups were as follows. 1. With regard to the body weight of each group that was injected intraperitoneally with single cadmium doses of 0.5, 1.O, 2.O and 3.Omg/kg the last two groups showed a significant decrease in one week. 2. Relative testicular weight (testicular weight ,body weight) one week after cadmium administration decreased significantly in the group of more than 1.Omg/kg administration. However, in the pretreatment groups, it was found that the group pretreated with cadmium did not decrease. 3. Cadmium concentration in the testicle in each group increased with the amount of cadmium doses. However, in the pretreatment group, the groups pretreated with cadmium and manganese did not increase. 4. In histopathological findings of the testicle on the 7the day after cadmium administration, the minimum dose of cadmium that induced edema in the interstitial tissue and inactive spermatogenesis in a few germinal epithelia was O.5 mg/kg, but the changes seemed to be due to inhibitory effect for spermatogenesis rather than direct injury to the testicular tissue. Necrosis was observed in the spermatogenic epithelium in the 2.O mg/kg group and severe necroses were extended to the interstitial tissue in the 3.O mg/kg group. The critical concentrations of cadmium for the histopathological change in the testicular tissue was 0.32ug/g and that for necrotic change was 0.60ug/g. 5. Protective effect in the pretreatment groups was noticeable in the cadmium pretreated group and moderate effect in the manganese group; however, in the other metal groups and the phenobarbital group little effect was observed. 6. Comparison of the histopathological findings between the group of pretreatment showing effect.
Animals ; Body Weight ; Cadmium Poisoning ; Cadmium* ; Edema ; Epithelium ; Humans ; Male ; Manganese ; Metals* ; Mice* ; Necrosis ; Phenobarbital ; Spermatogenesis ; Testis* ; Weights and Measures

OBJECTIVETo study the effect of Lycium barbarum polysaccharides (LBP) on neurogenesis and learning & memory of manganese poisoning mice.

METHODSHealthy adult Kunming mice were divided into 5 groups, the control group (A), the manganese poisoning (by manganese chloride peritoneal injection) group (B), the manganese poisoning and treated with gastric perfusion of high, medium, low dosage LBP groups (C, D and E). The spatial learning & memory capacity of mouse was determined by Morris water maze training test. The neurogenetic cells were labelled with bromodeoxyuridine (BrdU) and detected by immunohistochemistry.

RESULTSThe average escape latency was significantly higher and the times of passing through platform lower in group B than those in group A (P<0.05). BrdU positive cells in groups C, D and E were significantly more than those in group B (P<0.05).

CONCLUSIONLBP could enhance the learning & memory capability of the manganese poisoning mice by promoting neurogenesis in hippocampus.

Animals ; Drugs, Chinese Herbal ; pharmacology ; Learning ; drug effects ; Male ; Manganese Poisoning ; Memory ; drug effects ; Mice ; Mice, Inbred Strains ; Neurogenesis ; drug effects