The effect of recombinant human lactoferrin from the milk of transgenic cows on Salmonella enterica serovar typhimurium infection in mice

Lactoferrin (LF) is a multifunctional protein with antibacterial and immunomodulatory activities. Given this beneficial effect, transgenic approaches have been used to produce lactoferrin. The aim of the current study was to investigate the in vivo effect of recombinant human lactoferrin (rhLF) from the milk of transgenic cows on Salmonella enterica serovar typhimurium (ST) infection in mice. Two hours before the infection with 0.3 ml at 2 × 10(5) CFU ml(-1) of ST, each animal in the ST + rhLF group received 0.3 ml of rhLF with 20 mg ml(-1) concentration while the ST group received PBS as placebos with the same volume through oral gavage. The mice were infected with ST once only on the first day. After the infection, the mice received 0.3 ml of rhLF with 20 mg ml(-1) (6 mg d(-1)) concentration or PBS, respectively, for 7 days. Mortality and weight were monitored daily. Bacterial enumeration in the blood, liver, and spleen and histopathological analysis of the liver, spleen, kidney and intestine were conducted. The results showed that rhLF decreased the bacterial load in the liver and spleen of mice, reduced the degree of mice hepatomegaly and splenomegaly, and attenuated infectious inflammation with less histopathological abnormalities in the liver, spleen and kidney of mice in the ST infection. This study showed that rhLF with 6 mg per day had antibacterial activity of alleviating the infection caused by ST bacteria, which indicated that rhLF could be used as a supplement in special products.

Serum Copper Status in School-Age Children and Pregnant Women in China Nutrition and Health Survey 2010-2012

Serum copper is an insensitive but reliable biomarker reflecting the change of copper nutritional status in both depleted and replete populations. The current study aimed to establish the reference values of serum copper in school-age children and pregnant women in China and to explore the adequate range of serum copper for both these two categories of people. A multistage, stratified, random sampling combined with probability proportionate to regional size sampling method was employed. A total of 4019 subjects (2736 school-age children and 1283 pregnant women) were selected from China Nutrition and Health Survey 2010-2012 (CNHS 2010-2012). The concentration of serum copper was determined by sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). The adequate range of serum copper was determined by the logistic sigmoid saturation curve of the median derivatives. The median concentration of serum copper was 1140.9 μg/L with a range of 746.7-1677.6 μg/L for school-age children and 1933.4 μg/L with a range of 947.4-3391.4 μg/L for pregnant women. The adequate range of serum copper was 905.7-1440.7 μg/L for school-age children and 1308.8-2537.8 μg/L for pregnant women. These parameters represent an essential prerequisite for the assessment of copper nutritional status, as well as nutrition interventions.

[Study on the anemia status of Chinese urban residents in 2010-2012]

OBJECTIVE

The level of blood hemoglobin and the anemia status of Chinese urban residents in 2010-2012 was analyzed.

METHODS

All the data in this study came from the China Nutrition and Health Survey in 2010-2012. By using multi-stage stratified sampling and population proportional stratified random sampling method, 74 276 residents aged above 6 from 34 metropolis and 41 middle-sized and small cities were included in this study. The concentration of blood hemoglobin was determined by cyanmethemoglobin method. Anemia was judged by the anemia standard recommended by WHO, combined with elevation correction standard. The level of blood hemoglobin, the prevalence of anemia and the 95%CI value were analyzed by using the complex sampling weighted processing, combined with the population figures released by the National Bureau of Statistics in 2009.

RESULTS

In 2010-2012, the level of blood hemoglobin of Chinese city population was(144.16 ± 0.78)g/L, (152.88 ± 0.94)g/L for male and(135.01 ± 0.71)g/L for female, while (145.65 ± 1.22)g/L for metropolis and (143.90 ± 0.89)g/L for small and medium-sized. The anemia prevalence of Chinese city population (pregnant women were not included) was 9.7%(95%CI: 9.4%-10.1%), 6.8%(95%CI: 6.4%-7.3%) for male and 12.8%(95%CI: 12.2%-13.4%) for female, while 8.5%(95% CI: 8.0%-9.0%) for metropolis and 10.0%(95%CI: 9.5%-10.4%) for small and medium-sized. The anemia prevalence of 18-44 women (15.4%, 95%CI: 14.3%-16.6%) was the highest among all the age-groups, and the average anemia prevalence of people more than 60 years-old (including) (12.5%, 95%CI: 11.8%-13.2%) was higher than the other age-groups.

CONCLUSION

The anemia prevalence of Chinese city population in 2010-2012 was obviously decreased in comparison of 10 years ago, while, more attention and improvement measures should be take upon women at reproductive age and the elder people.

[Application of three different methods for estimating of the plasma volume in children]

OBJECTIVE

To investigate the difference between three methods for estimating the plasma volume in children.

METHODS

The blood volume of 57 children from 10 to 12 years old were estimated by weight, formula proposed by Woodhead, and by bioelectrical impedance analysis( BIA), the effect and consistency of three methods were also compared.

RESULTS

There was no difference between three methods in blood volume estimating( P > 0. 05). According to the results of Passing & Bablok regression regression analysis, the residual standard deviation( RSD) was 85. 88, 122. 83 and 111. 24. The regression equation were: y_(Woodhead)= 577. 356224 + 0. 800525x_(BW); y_(BIA)=1091. 590338 + 0. 653032x( BW); y( BIA)= 560. 545257 + 0. 843899x_(Woodhead), and there was no obvious departure from the linear correlation( P > 0. 05). After regrouping by the percent body fat, there were differences between three methods in weight in overweight and obese children group( P < 0. 05), the blood volume estimated by weight was thehighest, and by the BIA was the lowest. While in normal group there was no difference between three groups(P<0. 05).

CONCLUSION

Three methods in blood volume estimating has a good consistency, estimating by body weight and formula have the virtue of convenience. Method of BIA is extremely fit for application in children with higher body fat.

[Systemic evaluation of zinc nutritional status for children aged 2-5 years from rural areas of China in 2002]

OBJECTIVE

To perform zinc nutritional assessment of children aged 2- 5years in rural areas of China according to the joint recommendation by the WHO /UNICEF / IAEA / IZi NCG.

METHODS

Based on the project of China Nutrition and Health Survey 2002( CNHS 2002), a stratified sampling combined with the probability proportional to population size sampling method was employed. The concentration of plasma zinc was determined by high resolution inductively coupled plasm mass spectrometry, and the data of dietary zinc intake and the physical examination was collected. The assessment of zinc nutrition was obtained by 3 aspects of indicators involving plasma zinc, dietary zinc intake and the development of growth.

RESULTS

Plasma zinc concentration was 714. 9 μg / L, and 45. 5% of children with zinc deficiency. Dietary zinc intake was 5. 9 mg / d, and the prevalence of inadequate dietary zinc intake was 18. 1%. The height for age Z score was- 0. 8, with 18. 2% of children who were stunted.

CONCLUSION

Zinc nutritional status of children aged 2- 5 years in rural areas is poor in the CNHS 2002. The status of plasma zinc is utmost serious in comparison withother indicators. The status of zinc nutrition in children aged 2- 5 years from the 4th rural areas is required to be continuous attention. Zinc nutrional assessment provides an extremely useful information and technical reference for early childhood.

Comparison on the status of vitamin A in 6- to 13- year-old children between 2002 and 2012 in China

BACKGROUND

Vitamin A deficiency is recognized as a major public-health nutrition issue in the developing countries. Limited hospital sources and sample sizes are available in most of the existing studies associated with healthy school-age children. The aim of this study was to compare vitamin A status of 6- to 13-year-old healthy children in China between 2002 and 2012.

METHODS

According to China National Nutrition and Health Survey 2002 (CHNNS2002) and CHNNS2010-2013, we choose 6- to 13-year-old children as the research object. We measure the serum retinol concentrations of the children using high performance liquid chromatography (HPLC). The children were divided into two groups: 6- to 9-year-old and 10- to 13-year-old. The areas were divided into urban and rural area.

RESULTS

Total number of the children (6- to 13-year old) was 8170 in 2002 survey, and it was 6016 in 2012 survey. In 2012, the vitamin A level of the children was higher than that in 2002 (t = 39.26, p = 0.000). The level of vitamin A in 10- to 13-year-old group was higher than that in 6- to 9-year-old group across areas and genders between 2002 and 2012. There was no difference on the incidence of vitamin A deficiency in all the children between 2002 and 2012, but in 2012 the incidence of vitamin A deficiency in the urban children was higher than that in 2002 (x (2) = 45.456,p = 0.000). The incidence of vitamin A deficiency in 10- to 13-year-old group was lower than that in 10- to 13-year-old group across areas and genders between 2002 and 2012. In 2012, the incidence of marginal vitamin A deficiency in the children was lower than that in 2002 (x (2) = 861.604, p = 0.000). Similar phenomena were also found in across area groups. The incidence of marginal vitamin A deficiency in 10- to 13-year-old group was lower than that in 6- to 9-year-old group across areas and genders between 2002 and 2012. There was no difference in vitamin A status of the children across the area, gender and age groups between 2002 and 2012.

CONCLUSION

Vitamin A nutritional status of the children in 2012 has been significantly improved compared with that in 2002. However, vitamin A deficiency was still a moderate public health problem in Chinese children, especially in younger school-age children. Consequently, controlling the incidence of vitamin a deficiency is imperative for promoting Chinese children's health.

[Association of leptin receptor gene polymorphrism with metabolic syndrome in older Han adults from major cities in China]

OBJECTIVE

To investigate the relationship of leptin receptor gene rs1137100 and rs1137101 single nucleotide polymorphrism (SNP) with metabolic syndrome (MS) in older Han adults from major cities in China.

METHODS

A total of 2082 older Han adults were selected from 18 major cities including 15 provinces/municipalities of China National Nutrition and Health Survey in 2002. According to the MS definition proposed by Joint Interim Statement (JIS), the subjects were divided into MS and control groups. Plasma leptin and insulin levels were measured. The genotypes of rs1137100 and rs1137101 were detected by Taqman method. Association of genotypes of leptin receptor gene SNPs with MS was investigated.

RESULTS

The MS group showed higher body mass index (BMI), waist circumference, fasting serum glucose, systolic blood pressure (SBP) and diastolic blood pressure (DBP), triglycerides (TG), serum total cholesterol (TC), insulin, homeostasis model of assessment for insulin resistence index (HOMA-IR) and leptin levels than those of control individuals, while the high density lipoprotein cholesterol (HDL-c) was significantly lower than the control group. The, GG, AA, GA genotypes distribution and the A allele frequency of rs1137100 and rs1137101 were similar between the two groups. The DBP and SBP level were obviously higher in AA genotype. The HDL-c concentration Was significantly lower in AA and GA + AA genotype. The AA and GA genotypes carriers in rs1137100 had similar risk for MS when comparing with the GG genotypes, and the OR values were 1.23 (95% CI 0.90-1.67) and 2.23 (95% CI 0.83-6.44), respectively. The AA and GA genotypes carriers in rs1137101 had similar risk for MS when comparing with the GG genotypes, and the OR values were 1.23 (95% CI 0.90-1.67) and 2.23 (95% CI 0.83-6.44), respectively.

CONCLUSION

Leptin receptor genes rs1137100 and rs1137101 are not associated with pathogenesis of MS in older Han adults, but it may relate with hypertension or lipid abnormality.

Non-Heme Iron Absorption and Utilization from Typical Whole Chinese Diets in Young Chinese Urban Men Measured by a Double-Labeled Stable Isotope Technique

BACKGROUND

This study was to observe the non-heme iron absorption and biological utilization from typical whole Chinese diets in young Chinese healthy urban men, and to observe if the iron absorption and utilization could be affected by the staple food patterns of Southern and Northern China.

MATERIALS AND METHODS

Twenty-two young urban men aged 18-24 years were recruited and randomly assigned to two groups in which the staple food was rice and steamed buns, respectively. Each subject received 3 meals containing approximately 3.25 mg stable 57FeSO4 (the ratio of 57Fe content in breakfast, lunch and dinner was 1:2:2) daily for 2 consecutive days. In addition, approximately 2.4 mg 58FeSO4 was administered intravenously to each subject at 30-60 min after dinner each day. Blood samples were collected from each subject to measure the enrichment of the 57Fe and 58Fe. Fourteen days after the experimental diet, non-heme iron absorption was assessed by measuring 57Fe incorporation into red blood cells, and absorbed iron utilization was determined according to the red blood cell incorporation of intravenously infused 58Fe SO4.

RESULTS

Non-heme iron intake values overall, and in the rice and steamed buns groups were 12.8 ±2.1, 11.3±1.3 and 14.3±1.5 mg, respectively; the mean 57Fe absorption rates were 11±7%, 13±7%, and 8±4%, respectively; and the mean infused 58Fe utilization rates were 85±8%, 84±6%, and 85±10%, respectively. There was no significantly difference in the iron intakes, and 57Fe absorption and infused 58Fe utilization rates between rice and steamed buns groups (all P>0.05).

CONCLUSION

We present the non-heme iron absorption and utilization rates from typical whole Chinese diets among young Chinese healthy urban men, which was not affected by the representative staple food patterns of Southern and Northern China. This study will provide a basis for the setting of Chinese iron DRIs.

Distribution of iron status among urban Chinese women

BACKGROUND AND OBJECTIVES

To assess the distribution of serum ferritin, serum soluble transferrin receptor and body iron among girls and women by age and anaemia.

METHODS AND STUDY DESIGN

Serum ferritin, serum soluble transferrin receptor and high sensitive C-reactive protein of 1625 and 1372 women in general and anaemic were measured in the National Health and Nutrition Survey commenced in 2010.

RESULTS

The distributions of serum ferritin, serum soluble transferrin receptor and body iron for 6-11-y, 12-17-y, 18-44-y, 45-59-y and >=60-y subgroups were significantly different. Both in population-representative women and those anaemic, the iron status of 18-44-y women was the lowest and that of 12-17-y girls the second lowest. The iron status of anaemic women was lower than that in representative women at ages 12-17 y, 18-44 y, 45-59 y and >=60 y.

CONCLUSION

Iron status in women of different ages and anaemic had different distributions, but consistently lower than that of population-representative women. The observed iron status of Chinese urban women supports program planning for iron nutrition promotion in women. Iron status information is also needed for men and to understand the pathogenesis which may be related to intake or loss.

Effect of NaFeEDTA-fortified soy sauce on zinc absorption in children

NaFeEDTA has been applied in many foods as an iron fortificant and is used to prevent iron deficiency in Fe-depleted populations. In China, soy sauce is fortified with NaFeEDTA to control iron deficiency. However, it is unclear whether Fe-fortified soy sauce affects zinc absorption. To investigate whether NaFeEDTA-fortified soy sauce affects zinc absorption in children, sixty children were enrolled in this study and randomly assigned to three groups (10 male children and 10 female children in each group). All children received daily 3 mg of (67)Zn and 1.2 mg of dysprosium orally, while the children in the three groups were supplemented with NaFeEDTA-fortified soy sauce (6 mg Fe, NaFeEDTA group), FeSO₄-fortified soy sauce (6 mg Fe, FeSO₄ group), and no iron-fortified soy sauce (control group), respectively. Fecal samples were collected during the experimental period and analyzed for the Zn content, (67)Zn isotope ratio and dysprosium content. The Fe intake from NaFeEDTA-fortified and FeSO₄-fortified groups was significantly higher than that in the control group (P < 0.0001). The daily total Zn intake was not significantly different among the three groups. There were no significant differences in fractional Zn absorption (FZA) (P = 0.3895), dysprosium recovery (P = 0.7498) and Zn absorption (P = 0.5940) among the three groups. Therefore, NaFeEDTA-fortified soy sauce does not affect Zn bioavailability in children.

Prevalence and influence factors of vitamin A deficiency of Chinese pregnant women

Background

Vitamin A plays an important role in the periods of rapid cellular growth and differentiation, especially during pregnancy, which is supplied by the mother to the fetus. The aim of this study is to assess the prevalence and potential influence factors of prenatal VAD of Chinese pregnant women.

Methods

China National Nutrition and Health Survey 2010–2013(CHNNS2010–2013) is a nationally representative cross-sectional study. It involved the random selection of 150 districts (urban) or counties (rural). Each site randomly selected 30 pregnant women. Because volume of blood and incomplete data was taken into consideration,the final sample was formed by 1209 participants. Serum retinol concentrations were measured by high performance liquid chromatography. Characteristics of the pregnant women were collected by a questionnaire. Comparing retinol level across categories of independent variables was tested by the Mann-Whitney U test. Logistic and linear regression analyses were used to identify influence factors of Chinese pregnant women.

Results

The mean serum retinol level of the pregnant women was 1.63 μmol/L (95 % CI 1.60–1.67) and 64[5.3 % (95 % CI 4.03–6.56)] had VAD. The odds of VAD were significantly higher among the pregnant women in the poor rural areas and without college or university education and low- income. Pregnant women in the second and third trimester had 2.40 (95 % CI 1.05–5.46) and 2.82 (95 % CI 1.34–5.93) times increased odds of VAD compared with those in the first trimester respectively. Pregnant women of drinker had 3.10(1.65–5.81) times increased odds of VAD compared with those no drinker. Pregnant smokers had 5.68 (95 % CI 2.23–14.49) times higher odds of VAD compared with pregnant with non-smoker without passive smoking.

Conclusions

VAD is of mild public-health issue in Chinese pregnant women. Such as : in the poor rural areas and without received college or university education and low- income and advanced gestational age and unhealthy lifestyles of pregnant women such as smoking and drinking. These were pertinent influence factors of VAD.

HPV16 E6 mutations and p53 codon72 polymorphism among women with cervical intraepithelial neoplasia 2 and 3 in China

OBJECTIVE

To study the distribution of HPV16 E6 gene mutations and p53 codon72 polymorphism among women with HPV16+ cervical precancerous lesions and explore their relationship with the risk of cervical intraepithelial neoplasia (CIN) 2, 3. Materials and Meth- ods: This study analyzed a total of 112 cases of exfoliated HPV16+ cervical cell specimens which were divided into group I (normal and CIN1, 55 cases) and group2 (CIN2, 3, 57 cases). Among the 112 specimens, 85 cases were successfully amplified for HPV E6 gene by PCR and the PCR products were sequenced directly. P53 codon72 region was also amplified from the 112 specimens and the PCR products were sequenced directly and compared with the standard sequence.

RESULTS

Among the 85 amplified HPV sequences, point mutations such as T178G, T350G, G132A, A442C, T310G, G94T, C551A, etc. were found, among which, T178G showed the highest rate (51.76%). The rate of HPV16 E6 mutation T178G in CIN2, 3 group was significantly higher than that in normal and CINI group, i.e., in the 112 amplified p53 codon72 sequences, the distribution of Pro/Pro genotype in normal, and CIN1 group was significantly different from that in CIN2, 3 groups, and the disease risk of Pro/Pro genotype was much higher than that of Arg/Arg and Arg/Pro genotypes.

CONCLUSION

HPV16 E6 T178G mutation increases the disease risk of CIN2, 3. Meanwhile, compared with Arg/Arg and Arg/Pro genotypes, p53 codon72 Pro/Pro genotype more associated with the disease risk of CIN2, 3.

Association of Vitamin A Status with Overnutrition in Children and Adolescents

This study was conducted to examine the possible association between vitamin A status and overnutrition in Chinese urban children and adolescents. Weight, height and serum retinol were assessed in total 3457 children (7–9.9 years of age) and adolescents (10–17 years of age), using urban region data from the China National Nutrition and Health Survey 2010–2013 (CHNNS2010-2013) which is a nationally representative cross-sectional study. Prevalence of low serum concentration of retinol was 26.8% and 12.24% for overweight. Retinol inadequacy was significantly higher in children (32.13%) than in adolescents (24.48%). The average of retinol was significantly higher in overnutrified 42.32 μg/dL versus non-overnutrified 41.05 μg/dL (p = 0.00) children and adolescents. Overnutrified children and adolescents presented a greater chance of an increase in serum concentration of retinol (odds ratio 1.34, 95% confidence interval 1.10–1.63, and 1.48, 95% confidence interval (1.26–1.74) when compared with non-overnutrified children. An important correspondence between vitamin A deficiency and overnutrition was found. Non-overnutrified children and adolescents may have a greater chance of presenting low concentrations of retinol. Future public health strategies focused on the overnutrified population and vitamin A supplements should consider the effect of retinol on urban children and adolescents in China.

[Study on iron store status for women in the poor rural areas in China from 2010 to 2012]

OBJECTIVE

To quantitatively assess the concentration and the distribution of the body iron (BI) for women in the poor rural areas.

METHODS

Resampling based on the blood sample of Nutrition and Health Survey in China from 2010 to 2012, serum ferritin (SF) and serum soluble transferrin receptor (sTfR) were measured for the selected blood samples by immunoturbidimetric assay. BI was calculated, and the concentrations and distribution in different aged subgroup were assessed. Distribution of BI subgrouped in different aged women was compared. The correlations of BI to hemoglobin (Hb), SF and sTfR were analyzed.

RESULTS

The average levels of BI were (7.35 ± 2.37) mg/kg for schoolgirls aged 6-11 years, (6.50 ± 3.59) mg/kg for adolescent girls aged 12-17 years, (6.07 ± 4.78) mg/kg for women of childbearing aged 18-44 years, (8.60 ± 4.45) mg/kg for women aged 45-59 years, and (10.35 ± 3.38) mg/kg for elderly female aged ≥ 60 years, respectively. The proportion of low BI in the 12-17 years and 18-44 years women was the highest. BI level was positively correlated to SF and negatively correlated to sTfR (P < 0.01). BI level was positively correlated to Hb in the BI < 0 mg/kg subgroup.

CONCLUSION

The BI methodology allows the full range of iron status of populations to be evaluated. The iron status for adolesecent girls aged 12-17 years and women of childbearing aged 18-44 years should be improved.

[Comparison for ELISA and CLIA of serum 25-hydroxy vitamin D determination]

OBJECTIVE

To estimate the bias between the enzyme linked immunosorbent assay (ELISA) and chemiluminescence immunoassay (CLIA) of serum 25-hydroxy vitamin D (25 (OH) D) determination, and to evaluate the correspondence of two methods.

METHODS

Forty human serum samples were collected, and the serum 25 (OH) D were determined by immunodiagnostic systems 25-hydroxy vitamin D EIA and immunodiagnostic systems iSYS analyser. According to the standards of NCCLS EP9-A2 files, the within and without outlier, test adequate range, used linear regression procedure, and compare average and maximum bias between these two methods were excluded.

RESULTS

In the linear regression analysis, the results of the two methods were correlated, y = 0.995x + 2.3928, r = 0.981. The relative standard deviation between these two methods was smaller with the higher serum 25(OH) D levels.

CONCLUSION

The correlation and repeatability of serum 25 (OH) D determination by ELISA and CLIA are fine.

[Effect of different dietary fat intake on blood lipids, body fat, adiponectin and leptin on energy balance status in rats]

OBJECTIVE

To investigate the effects of different dietary fat intake on body fat, adiponectin and leptin on energy balance status in rats.

METHODS

Forty male SD rats were randomly assigned to four groups. Rats in low fat, normal fat, medium fat and high fat group were fed equal energy diets of low fat diet (5% energy from fat), normal diet (15% energy from fat), medium fat diet (25% energy from fat) and high fat diet (40% energy from fat) respectively. Blood glucose and lipids were analyzed at 0, 5 and 10 weeks. The level of serum adiponectin and leptin was tested at 0 and 10 weeks. At the end of 10 weeks, the rats were sacrificed, the perirenal and periepididymis fat were separated and weighed. The mRNA of adiponectin and leptin in fat tissues were determined by realtime PCR.

RESULTS

After the 5 and 10 weeks, the levels of serum triglyceride of rats in medium fat group and high fat group were lower than those in low fat group and normal fat group. At the end of 10 weeks, the expression of adiponectin mRNA in fat tissues in medium fat group was lower than those in low fat group. There were no significant differences among four groups in body fat, blood glucose, blood cholesterol, serum adiponectin and leptin, and the expression of leptin mRNA in fat tissues.

CONCLUSION

In energy balance status, different dietary fat intake had no effects on body fat, blood glucose, blood cholesterol, serum adiponectin and leptin in rats.

[Study on IgE mediated food allergy of 3 -12 years urban children in China]

OBJECTIVE

To study the situation of IgE-mediated food allergy of Chinese urban children, including the rate of food allergy and the main food allergens in children.

METHODS

All the serum samples were selected from the serum bank built by the national nutrition and health survey of Chinese residents. Total IgE of all the samples were tested by enzyme linked immunosorbent assay, and the sIgE of TIgE-positive samples were then tested by immunoblotting.

RESULTS

A total of 5190 samples were selected from serum bank, and the rate of IgE-mediated food allergy was 3.20%. The rate of IgE-mediated food allergy was 2.70% in big cities, while it was 3.77% in small and medium-sized cities. The rate was gradually decreased with age grown.

CONCLUSION

The situation of food allergy in children and the main allergens could be preliminary determined by testing the serum total IgE level and specific IgE.

[Study on efficiency of iron utilization in prepubertal female children]

OBJECTIVE

To investigate the iron utilization of prepubertal female children.

METHODS

27 female children from 10 to 12 years old were selected and given 57Fe as a tracer, in conventional diet mode, the blood samples in 1 day before test, 14 days and 28 days after tracer given were taken, and were conducted into red blood cell sample. The iron content and changes of isotope abundance in samples were analyzed and combined with blood volume to get the utilization of iron in RBC.

RESULTS

The erythrocyte incorporation rate( of dose) in 14 days and 28 days were (19.84 +/- 0.53)% and (18.75 +/- 0.40)% (P > 0.05). The erythrocyte incorporation rate( of absorption) were (93.49 +/- 2.27)% and (88.73 +/- 0.43)% respectively, and there was a significantly difference (P < 0.05).

CONCLUSION

It is feasible and accurate to evaluate the iron utilization using erythrocyte incorporation rate, which is tested by single stable isotopes tracer technique. Prepubertal female children has a higher utilization of iron, and the 14 days after tracer given is a effective entry point in erythrocyte incorporation study.

[Evaluation on the iron absorption of prepubertal children using stable isotopic tracer]

OBJECTIVE

To investigate the iron absorption of prepubertal children using stable isotopic tracer.

METHODS

57 subjects were orally given 57FeSO4, in conventional diet mode, before breakfast and supper and totally for 5 days. All the fecal during the specified time were collected, pre-conducted and determined by AAS and MC-ICP-MS to evaluation the iron absorption of prepubertal children.

RESULTS

The iron absorption rate of male and female were (26.71 +/- 2.94)% and (29.76 +/- 2.20)%, and the correction absorption rate of iron were (27.45 +/- 2.83)% and (31.01 +/- 2.48)%, absorption of female were higher than that of male (P < 0.05).

CONCLUSION

In the condition of fasting oral SI, there is a high iron absorption rate of prepubertal children, and absorption rate of female is higher.

[Simultaneous determination of 12 trace elements in children plasma sample by high resolution inductively coupled plasma mass spectrometry]

OBJECTIVE

To establish a method of determination of 12 trace elements (B, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Sr, Mo) in children plasma for the fast,direct dilution by HR-ICP-MS.

METHODS

The plasma samples were reconstituted, centrifuged for 15 minutes, then were added the internal elements of Ga and Y, diluted with 0.5% HNO3 by 1 : 20 (V/V). HR-ICP-MS was optimized and applied for the analysis.

RESULTS

Detection limits were 0.001 - 0.035 microg/L, method detection limits of trace elements were 0.012 - 0.702 microg/L, coefficient of determination (R2) ranged from 0.9983 to 1. 0000 and the 3 levels of spiked recovery were between 85.86% and 121.34%, intra-day and inter-day precision were 0.52% - 5.62% and 1.21% - 10.21%, as well as bovine serum certified samples further verified the accuracy. 12 trace elements in plasma of the children aged 3 -12 years from poor rural in 2002 CNNHS, had been determined by Optimized HR-ICP-MS.

CONCLUSION

Preparation of plasma samples with 0.5% HNO3 combined with HR-ICP-MS were applied for a large scale of sample analysis.