Investigations Of Serum Levels Of Zinc,Magnesium And Zinc/Copper And The Relationshiops With Some Correlative Factors In Healthy Adults Of Jinan

Objectives1. To investigate serum levels of Zinc, Magnesium and zinc/copper of healthy adults in Jinan for evaluating the reference intervals of serum Zinc, Magnesium and zinc/copper of healthy adults in Jinan.2. To evaluate the influences of some demographic factors such as sex, age, average home income, educational levels on serum levels of Zinc, Magnesium and zinc/copper of healthy adults in Jinan.3. To evaluate the influences of human behaviors such as smoking, drinking, frequency of drinking, frequency of physical exercise, and hours of night sleep on serum levels of Zinc, Magnesium and zinc/copper of healthy adults in Jinan.4. To screen primary influencing factors of serum levels of Zinc, Magnesium and zinc/copper of healthy adults in Jinan and further study single effect of each factor.5. To investigate the levels of Zinc, Magnesium and zinc/copper in someenvironmental mediums of Jinan city such as the soil and food in order to study the influences of environmental factors on serum Zinc, Magnesium and zinc/copper in healthy adults of Jinan.Methods1. The optimal working conditions of microwave digestion and atomic absorption spectrometer (AAS) were fixed through some experiments of evaluating the influences of electrical current, air flow rate and gas flow rate on the accuracy and precise of AAS by orthogonal experimental design and replication experiments ccording to similar literature researchs and s;2. The accuracy and precise of microwave digestion-AAS after 12h cold-wet digestion were evaluated by methodological studies such as the experinments of comparison and percent recovery rate;3. Healthy adults of Lixia and Huaiyin districts were chosen by sub-systematic sampling and the data of demographic factors and human behaviors were collected by questionnaires.And then serun Zinc and Magnesium concentrations of the whole samples were detected by AAS after cold wet and microwave digestion;4. The influences of demographic factors such as sex, age, average home income, educational levels and human behavioral factors such as smoking, drinking, frequency of drinking, frequency of physical exercise, and hours of night sleep on serum levels of Zinc, Magnesium and zinc/copper of healthy adults in Jinan were evaluated by single factor analysis and general linear analysis, and primary influencing factors were screened through establishing optimal linear regression equation;5. The concentrations of Zinc and Magnesium in some foods such as vegetable, fruit, bean, paddy, meat and the soil were detected by wet digestion-AAS and Zinc/Copper was counted for the results compared with the references promulgated by CDC of China in 2002.Results1. The optimal electronical current, air flow rate and gas flow rate for Zinc were 7.0mA, 2.5kg.cm^-2 and 1.4kg.cm, respectively.The optimal electronical current, air flow rate and gas flow rate for Magnesium were 5.0mA, 2.5kg.cm^-2 and 1.2kg.cm^-2, respectively.2. Serum levels of Zinc and Zinc/Copper were 1.32±0.49mg/l and 1.41±0.56 respectively, which were higher than that of other cities. Serum Magnesium concentration was 19.36±3.81mg/l, which was similar to others.3. According to single factor analysis, higher serum Zinc(P>0.05) and Magnesium (P>0.05) concentration and Zinc/Copper(P<0.05) were observed in the men than the women. No significantly(P>0.05) descending tendency of serum Zn and Zn/Cu was observed with age increasing,but ascending tendency was in the inteval of 50-60 years.And no clear relationships between social-economic status and educational levels serum Zn,Mg and Zn/Cu were observed.4. According to single factor analysis,no significantly(P>0.05) lower serum Zn concentration but higher Mg concentrations and Zn/Cu were observed in smokers than that in nonsmokers but not significant(P>0.05).Higher levels of serum Zn,Mg and Zn/Cu were observed in drinkers than that in nondrinkers and ascending with the frequency of drinking increasing.Ascending tendencies of serum Zn and Zn/Cu were observed with the frequency of physical exercise increasing but not significant(P>0.05). Serum Zn concentration and Zn/Cu kept normal only when hours of sleep a night were among 7-9 hours.5. According to general linear analysis, lower serun Zinc concentration was observed in men than that in women and no significantly serum Zn and Mg concentrations were in drinkers than that in nondrinkers, which were dissimiliar to the results by single factor analysis.Other results were similar to that by single factor analysis.6. It was observed that lowest Zinc concentration and Zinc/Copper were in the soil sample collected from central park of West schoolyard of Shandong University and highest Mg concentration was in that around moat of Wenhua west road. Zinc concentrations and Zinc/Copper were lower in the vegetables and higher in the fruits, beans, paddy, peanut and chicken.Conclusions1. The method of microwave digestion-AAS after 12h cold-wet digestion was suitable to detect serum Zinc and Mg concentrations.2. Higher serum concentrations of Zinc and Zinc/Copper were observed in healthy residents of Jinan, which may be associated with higher Zinc concentrations in local fruit, paddy, and bean, peanut and chicken and especially with the eating habit that Jinan residents preferring chicken and mutton. Lower Zinc concentration and Zn/Cu were observed in the vegetables of Jinan, which could suggest Jinan residents should take more vegetables in order to adjust higher serum Zn concentration and Zn/Cu.3. Higher Zinc concentration and Zn/Cu were detected in the men than that in the women, which may be associated with men's drinking habit and higher frequency. Serum Zn concentration and Zn/Cu were observed decreasing with age increasing but increasing when age over 50 years, which may be associated with different demand during each group period.4. Smoking behavior could cause lower Zinc concentration and higher Mg and Zinc/Copper in serum, which suggested moderate drinking and smoking forbidden were good for human health. Serum Zn concentration and Zn/Cu kept normal only when hours of sleep a night were among 7-9 hours. It suggested we need to increase Zn intake to make up the weak Zn absorption with age increasing and keep adequate night sleep time (7-9hours) and regular physical exercise to maintain the balance of serum Zn in human body and satisfy the need of keeping healthy.The main features and creative points of this thesis are as follows:1. Evaluate the influences of electrical current, air flow rate and gas flow rate on the accuracy and precise of AAS by orthogonal experimental design and replication experiments according to similar literature researchs, to make sure the optimal working conditions of microwave digestion and AAS, moreover, to reduce experimental workload.2. 500 healthy adults of Lixia and Huaiyin districts chosen by sub-systematic sampling, satisfy representative samples, and furthermore, reduce the worklord of the investigation.3. For the first time large-scale investigation of serum levels of Zinc, Magnesium and zinc/copper of healthy adults in Jinan.4. First time comprehensive evaluation of single and integral action of some demographic factors, behavioral factor and environmental factors and confound factors on serum Zinc, Magnesium and zinc/copper.5. Evaluating the relationships between such factors with serum levels of Zinc, Magnesium and zinc/copper by single factor analysis and general linear analysis at the same time.