Reevaluation of the protein requirement in Chinese elderly adults without sarcopenia with the indicator amino acid oxidation technique.

It is now generally believed that elderly may have slightly higher dietary protein requirements than those of the young-middle-aged adults. We have previously conducted related studies by the indicator amino acid oxidation (IAAO) technique, but more research data are needed to revise the protein requirements of the elderly. The main objective was to reevaluate the dietary protein requirements of healthy Chinese adults (65-80 years) without sarcopenia by using the IAAO technique. Nine healthy adult men and seven healthy adult women participated in the study, with protein intakes ranging from 0·1 to 1·8 g/(kg·d). Diets that delivered energy at a 1·5 resting energy expenditure were isocaloric. The amounts of phenylalanine and tyrosine needed to remain constant for each protein dosage. By applying a nonlinear mixed-effects model analysis on the F13CO2 data, which revealed a breakpoint in F13CO2 in response to graded protein intakes, the mean protein requirement was calculated. The mean estimated average requirement (EAR) for healthy elderly Chinese adults without sarcopenia was determined to be 0·94 g/(kg·d). The protein recommended nutrient intake (RNI) determined using various derivation approaches ranged from 1·13 to 1·36 g/(kg·d). The EAR for Chinese adults without sarcopenia aged 65-80 years in this study is 6·8 % higher than the current recommended EAR (0·88 g/(kg·d)). The RNI derived using various derivation approaches are all greater than the current RNI (0·98 g/(kg·d)). This trial was registered with the Chinese clinical trial registry as ChiCTR2200061382.

[Changes in protein requirements of elderly people over 5 years assessed using the indicator amino acid oxidation method].

OBJECTIVE: To evaluate the changes in protein requirements of the elderly during the past five years. METHODS: Based on the previous study of protein requirements of 14 elderly in 2017, 4 of these elderly(70-80 y) were included as study participants and protein requirements were re-evaluated using the indicator amino acid oxidation method. There were seven protein levels: 0.1, 0.3, 0.6, 0.9, 1.2, 1.5 and 1.8 g/(kg·d). Maintenance diets were given for the first two days of each protein level. A stable isotope study was conducted on the day 3, using L-~(13)C-phenylalanine as an indicator on the basis of an amino acid rationed diet, which was orally ingested into the body along with the amino acid rationed diet, and breath and urine samples were collected when the metabolism of L-~(13)C-phenylalanine reached steady state in the body. By measuring the kinetic parameters of labeled amino acids in the samples, a nonlinear mixed-effects model was constructed for the protein intake to be tested and the oxidation rate of labeled amino acids. The mean protein requirement of the study population was determined by the protein intake corresponding to the inflection point of the curve. RESULTS: Based on the production rate of ~(13)CO_2 in exhaled breath of four elderly people at different protein levels, the mean protein requirement was 1.05(95%CI 0.51-1.60) g/(kg·d). The protein recommended nutrient intake was 1.31(95%CI 0.64-2.00) g/(kg·d) was estimated by applying the coefficient of variation of the mean protein requirement to derive the recommended nutrient intake. CONCLUSION: Protein requirements in the elderly have increased over a five-year period and sarcopenia may be the main cause of increased protein requirements.

Re-exploration of dietary iodine intake in Chinese adult males using a modified iodine balance study.

There is still controversy about optimal dietary iodine intake as the Universal Salt Iodization policy enforcement in China. A modified iodine balance study was thus conducted to explore the suitable iodine intake in Chinese adult males using the iodine overflow hypothesis. In this study, thirty-eight apparently healthy males (19·1 (sd 0·6) years) were recruited and provided with designed diets. After the 14-d iodine depletion, daily iodine intake gradually increased in the 30-d iodine supplementation, consisting of six stages and each of 5 d. All foods and excreta (urine, faeces) were collected to examine daily iodine intake, iodine excretion and the changes of iodine increment in relation to those values at stage 1. The dose-response associations of iodine intake increment with excretion increment were fitted by the mixed effects models, as well as with retention increment. Daily iodine intake and excretion were 16·3 and 54·3 µg/d at stage 1, and iodine intake increment increased from 11·2 µg/d at stage 2 to 118·0 µg/d at stage 6, while excretion increment elevated from 21·5 to 95·0 µg/d. A zero iodine balance was dynamically achieved as 48·0 µg/d of iodine intake. The estimated average requirement and recommended nutrient intake were severally 48·0 and 67·2 µg/d, which could be corresponded to a daily iodine intake of 0·74 and 1·04 µg/kg per d. The results of our study indicate that roughly half of current iodine intakes recommendation could be enough in Chinese adult males, which would be beneficial for the revision of dietary reference intakes.

Re-exploring the requirement of dietary iodine intake in Chinese female adults based on 'iodine overflow theory'.

PURPOSE: We re-explored the basal iodine requirement based on healthy Chinese female and a new iodine overflow theory was proposed for iodine balance study. METHODS: Thirty-six Chinese healthy female adults (age 20.7 ± 1.1) were recruited for this study, which included 40 days low iodine depletion period and six stages of 30 days supplementation period. Uniform diets with low iodine were provided and the content of iodine in the diet was regulated by dairy products. The total iodine intake from food and the total iodine excretion through 24-h urine and staged feces were completely gathered and monitored. The incremental (Δ) intake and excretion over the range were calculated. RESULTS: The iodine intake and excretion were 13.6 µg/day and 48.6 µg/day at the first stage, respectively. The incremental iodine intakes and excretions were 21.1 µg/day to 120.3 µg/day and 25.8 µg/day to 105.4 µg/day for the supplementation stages, respectively. According to the 'iodine overflow theory', the zero iodine balance (Δ iodine intake = Δ iodine excretion) derived from a mixed effect model indicated a mean iodine intake of 52.2 µg/d (1.0 µg/d kg). The RNI for iodine to healthy Chinese female adult was 73.1 µg/d (1.4 µg/d kg). CONCLUSION: A daily iodine intake of 52.2 µg/d may meet the basal iodine requirement for healthy Chinese female adults, and Chinese female may need more than 20% iodine intake than male based on the 'iodine overflow theory'. The trial was registered at the Chinese Clinical Trial Registry in May 2018 (No: ChiCTR1800016184).

[Plasma selenium level and its influencing factors in Chinese child-bearing-aged women in 2015].

OBJECTIVE: To assess the plasma selenium(Se) level of child-bearing-aged women and discuss the influence factor for low-Se level. METHODS: Using the muti-stage stratified and population proportional cluster random sampling method, 1881 child-bearing-aged women aged 18 to 44 years were selected from China Adult Chronic Disease and Nutrition Surveillance(2015) Data. The basic information of the subjects was collected by unified electronic questionnaires and equipments were used for field survey, measurement and record. Plasma Se concentration was detected by inductively coupled plasma mass spectrometry. Plasma low-Se level were assessed using lower limit of plasma/serum Se established by the Mayo Clinic Laboratory and our laboratory, respectively. Influence factors of low-Se level were analyzed by the multivariate logistic regression model. RESULTS: The M(P25, P75) plasma Se concentration for Chinese child-bearing-aged women was 89.52(74.21, 105.03)µg/L. Nationality, location, urban-rural type and education level difference had influence on plasma Se level in this population(P<0.05). According to the lower limit of plasma/serum Se concentration established by the Mayo clinical laboratories(<70 µg/L) and our laboratories(<73.81 µg/L), the low-Se rate were 20.47% and 24.51%, respectively. There were significantly differences in low-Se rate among nationality, location, urban-rural type, education level and marital status(P<0.05). The multivariate logistic regression model showed that location and urban-rural type had significant effects on low-Se rate of child-bearing-aged women(P<0.05). CONCLUSION: The plasma low-Se rate of Chinese women of childbearing age is relatively high and higher prevalence low-Se was found in western and central regions and rural areas in China.

[Protein efficiency ratio of genetically modified pork powder with fat-1 gene].

OBJECTIVE: To evaluate the protein efficiency ratio(PER) of genetically modified pork powder with fat-1 gene(GM group), and thus evaluate whether the nutritional evaluation value of fat-1 gene pork powder has changed. METHODS: Sixty weaned SD rats(60-80 g) were randomly divided into casein group, parental control group and GM group according to sex and weight, 20 rats in each group, half of each sex. The rats in the three groups were fed with corresponding formulated feed containing 10% protein for 28 days. The body weight and food intake of each group were recorded weekly. Blood was collected at the end of the experiment to determine hematology and blood biochemical indexes. The food utilization rate, organ/body weigh indexes, PER and corrected PER were calculated. RESULTS: The weight of rats in all groups increased steadily during the experimental period. Statistically significant differences were found in some hematology and blood biochemical indexes and organ/body weigh indexes. No biologically significant changes were found. The food utilization rate of GM group was higher than that of casein group(P<0.05), which was equivalent to that in the parental control group. The PER of both genetically modified pork powder with fat-1 gene and parental white pork powder were higher than that of casein(P<0.05). CONCLUSION: The PER of genetically modified pork powder with fat-1 gene was equal to that of its parental white pork powder.

Exploration of the lower threshold of iodine intake in Southern Chinese young adults based on 'overflow theory' in an iodine balance study.

BACKGROUND: Appropriate iodine intake for adults is essential to reduce the prevalence of thyroid diseases, but there is little research data on iodine requirement of Chinese population. This study aimed to explore the iodine requirement of young adults to maintain a healthy status based on 'overflow theory'. METHODS: Iodine-balance experiment has been performed in this project. We conducted an 18-day study consisted of a 6-day acclimation period and 3 consecutive experimental stages in 37 Chinese healthy young adults (23 female and 14 male). Each stage was consumed for 4 days. Strictly-controlled low-iodine intake diets were provided for adults in the first period, an egg or 125mL milk was added in the second and third period, respectively. The dietary samples, 24-h urine specimens and faeces of volunteers were collected daily for assessment of iodine intake and excretion in volunteers. RESULTS: Mean values of iodine intake (22.7±3.6, 35.1±3.7, and 52.2±3.8µg/d), excretion (64.7±13.9, 62.3±12.6, and 94.3±14.5µg/d) and iodine balance (-35.2±19.5, -21.0±19.8, and -33.5±26.9µg/d) were significantly different among three periods for male (P<0.001 for all); mean values of iodine intake (16.6±3.1, 29.7±2.7, and 48.0±2.7µg/d), and excretion (47.0±9.9, 55.5±8.1, and 75.7±12.4µg/d) were significantly different among three periods for female (P < 0.001 for all). No significant difference was observed among the 3 periods for female in the iodine balance (-30.5±9.3, -25.9±7.3, and -27.6±12.1µg/d). The linear regression equation of iodine excretion on iodine intake was Y=0.979X+37.04 (male) and Y=0.895X+31.48 (female). Compared with stage 2, iodine excretion increments in stage 3 had exceeded the iodine intake increment for men. The ratio of increment was 1.675 for male when the average iodine intake was 52.2µg/d in stage 3. When the iodine excretion increment equaled to the iodine intake increment, the daily iodine intake of men was 47.0µg. CONCLUSION: We have evaluated the iodine requirement of young adults in southern China based on overflow theory. Our results indicate the lower limit of iodine requirement for Chinese young men is 47.0µg/d. The trial was registered at www.chictr.org.cn as ChiCTR1800014877.

[Protein efficiency ratio of genetically modified corn with Cry1Ab-ma gene].

OBJECTIVE: To evaluate the protein efficiency ratio(PER) of genetically modified corn with Cry1Ab-Ma gene and parental corn. METHODS: Sixty SD rats(60-80 g) were randomly divided into genetically modified corn group, parental corn group and casein control group, with 20 rats in each group and half male and half female. Casein was added to 10% of the diet in casein control group. When the protein content of the diets in the genetically modified corn group and parental corn group was still less than 10% according to the principle of maximum incorporation, the defective part was supplemented with casein. Rats were free to drink and eat for 28 days. Food intake and body weight of each group were recorded every week. Blood was collected at the end of the experiment to determine hematology and blood biochemical indexes. The main organs were weighed and organ/body weigh indexes were calculated. PER and corrected PER were calculated. RESULTS: The body weight of all the animals in each group showed an increasing trend, and the weight growth was normal. Although there were statistical differences in the individual indexes of end-stage hematology and blood biochemical indexes, there was no biological significance. There were no significant change in the organ/body weigh indexes. PER of genetically modified corn, parental corn and casein were 2.01±0.22, 1.77±0.30 and 3.64±0.48, respectively. The corrected PER of genetically modified corn and parent corn were 1.38 and 1.22, respectively. CONCLUSION: The PER of this batch of genetically modified corn with Cry1Ab-ma gene was better than that of parental corn, but worse than that of casein.

M1 Macrophage exosomes MiR-21a-5p aggravates inflammatory bowel disease through decreasing E-cadherin and subsequent ILC2 activation.

Abnormal immune regulation is a key feature of the complex pathogenic mechanism of ulcerative colitis (UC). In particular, macrophages and group 2 innate lymphoid cells (ILC2s) are important components of natural immunity that have been shown to play important roles in the pathogenesis of UC, as well as decreased E-cadherin expression on the colonic mucosa. However, it remains unclear how these components interact with each other. In this study, we investigated the molecular mechanisms of UC mediated by macrophage-derived exosomes. We showed for the first time that miR-21a-5p expression is increased in the peritoneal exosomes of mice with dextran sulphate sodium induced enteritis and that miR-21a-5p expression correlates negatively with E-cadherin expression in enterocytes. Moreover, we confirmed that miR-21a-5p was mainly derived from M1 macrophages and demonstrated that KLRG1, a surface inhibitory receptor on ILC2s, participated in excessive ILC2 activation in UC by promoting GATA-3. In conclusion, our results suggest molecular targets and provide a theoretical basis for elucidating the pathogenesis of UC and improving its treatment.

Low selenium intake is associated with postpartum weight retention in Chinese women and impaired physical development of their offspring.

The aim of this study was to investigate the association between daily Se intake and postpartum weight retention (PPWR) among Chinese lactating women, and the impact of their Se nutritional status on infants' physical development. Se contents in breast milk and plasma collected from 264 lactating Chinese women at the 42nd day postpartum were analysed with inductively coupled plasma MS. Daily Se intake was calculated based on plasma Se concentration. The dietary data of 24-h records on three consecutive days were collected. Infant growth status was evaluated with WHO standards by Z-scores. Linear regression analyses and multinomial logistic regression were conducted to examine the impact of Se disequilibrium (including other factors) on PPWR and growth of infants, respectively. The results indicated that: (1) the daily Se intake of the subjects was negatively associated with their PPWR (B = -0·002, 95 % CI - 0·003, 0·000, P = 0·039); (2) both insufficient Se daily intake (B = -0·001, OR 0·999, 95 % CI 0·998, 1·000, P = 0·014) and low level of Se in milk (B = -0·025, OR 0·975, 95 % CI 0·951, 0·999, P = 0·021) had potential associations with their infants' wasting, and low level of Se in milk (B = -0·159, OR 0·853, 95 % CI 0·743, 0·980, P = 0·024) had a significant association with their infants' overweight. In conclusion, the insufficient Se nutritional status of lactating Chinese women was first found as one possible influencing factor of their PPWR as well as low physical development of their offspring.

Thalidomide Attenuates Colitis and Is Associated with the Suppression of M1 Macrophage Polarization by Targeting the Transcription Factor IRF5.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease. The TNF-α inhibitor thalidomide is reported to be effective for inducing remission in pediatric Crohn's disease (CD) and adults with refractory CD. The mechanisms underlying the immunomodulatory and anti-inflammatory properties of thalidomide are unclear. METHODS: Histological assessments were firstly performed in thalidomide treated UC patients. Then the effect of thalidomide in vivo was detected in DSS-induced murine colitis. The mechanism involving IRF5, and M1 macrophage polarization was investigated by using plasmid transfection, western blotting, and real-time PCR. Finally, AOM/DSS model was used to detect the role of thalidomide in colitis associated cancer. RESULTS: We first found that treatment with thalidomide could ameliorate colon inflammation for 8 weeks and promote mucosal healing in human UC. Moreover, treatment with thalidomide protected mice from dextran sodium sulfate (DSS)-induced acute colitis, with treated mice presenting with a higher body weight, lower histological score, and lower DAI. Concomitantly, in comparison with control mice, mice treated with thalidomide showed accelerated recovery following colitis after 10 days of thalidomide treatment. Mechanistically, we observed that thalidomide could increase epithelial cell self-renewal capacity and modulate M1/M2 polarization by decreasing M1 markers CD86 and CCR7 and increasing M2 protein signatures CD206 and Arg-1. Thalidomide controls M1 macrophage polarization by targeting the transcription factor IRF5. Finally, by using the classical AOM/DSS model, we found that thalidomide-treated mice presented with a lower incidence and growth of colitis-associated carcinoma (CAC) than negative control mice. CONCLUSIONS: In summary, thalidomide suppresses M1 polarization in the inflammatory microenvironment, which not only attenuates colonic inflammation to facilitate mucosal healing after DSS-induced injury but also represses the progression of CAC.

Efficacy and safety of submucosal tunneling endoscopic resection for gastric submucosal tumors: a systematic review and meta-analysis.

INTRODUCTION: submucosal tunneling endoscopic resection (STER) can be an effective treatment for submucosal tumors (SMTs) in the esophagus and cardia. However, STER may be more difficult to perform in the stomach than in the esophagus due to special anatomical and physiological features. The feasibility of STER to remove gastric STMs has not been systematically investigated. Therefore, this meta-analysis aimed to evaluate the safety and efficacy of STER for gastric SMTs. MATERIAL AND METHODS: a comprehensive literature search of the Medline, Embase, PubMed, and Cochrane Library databases was conducted. Complete resection and en-bloc resection rates were considered as the primary outcome measures. The secondary outcome measure was the pooled estimate of complications. RESULTS: nine studies including 301 patients with 305 lesions were finally included. The pooled estimate of en-bloc resections was 95.1 % (95 % CI: 88.9-97.9 %), Cochran's Q-test, p = 0.151, and the weighted pooled rate (WPR) for complete resection was 97.9 % (95 % CI: 93.6-99.3 %), Cochran's Q-test, p = 0.778. In addition, the pooled estimate of gas-related complications was 8.7 % (95 % CI: 4.6-15.9 %), Cochran's Q-test, p = 0.057. The pooled estimate for mucosal laceration was 4.2 % (95 % CI: 2.2-7.9 %), Cochran's Q-test, p = 0.572. The pooled estimate for delayed bleeding was 2.1 % (95 % CI: 0.9-4.8 %), Cochran's Q-test, p = 0.985. The pooled estimate of inflammation-related complications was 8.6 % (95 % CI: 5.2-13.9 %), Cochran's Q-test, p = 0.308. CONCLUSION: STER is an effective and safe technique for removing gastric SMTs with low complications, and complications, when encountered, can be treated conservatively.

[Zinc status of 18-60 year-old adults in China in 2015].

OBJECTIVE: To estimate the distribution of serum zinc levels, zinc deficiency status and possible influencing factors in 18-60 year-old adults in China. METHODS: Based on the data of China Adult Chronic Disease and Nutrition Surveillance, 3903 blood samples were selected by stratified random sampling. The distribution of serum zinc in adults with different gender, age, regional type and regional distribution were analyzed by inductively coupled plasma mass spectrometry and body mass index(BMI), exercise, smoking, drinking, vitamin A level and other factors on serum zinc concentration and zinc deficiency rate. Multivariate logistic regression model was used to analyze the correlation between zinc deficiency and the influencing factors. RESULTS: In 2015, the median of serum zinc in Chinese adults aged 18-60 years was 103. 44(95%CI 64. 84-186. 12) µg/dL, and the overall zinc deficiency rate was 6. 04%. Serum zinc concentration had statistically significant difference(P<0. 05) in different genders, regional types, regional distribution, vitamin A status, smoking status, drinking status. In the comparison of zinc deficiency rates, ethnic minorities(10. 67 %) was higher than Han(5. 44%), rural area(7. 35%) was higher than urban area(4. 90%), vitamin A deficiency group(9. 12%) was higher than vitamin A normal group(5. 90%), non-exercise group(6. 29%) was higher than sports group(5. 09%). Among different regional distributions, the western region had the highest zinc deficiency rate(7. 33%), and among different BMI groups overweight group had the lowest rate(4. 81%). These differences were statistically significant(P<0. 05). In the analysis of multivariate logistic regression, the risk of zinc deficiency in the vitamin A deficiency group was 1. 89 higher than that of the normal group(OR=1. 89, 95%CI 1. 13-3. 18); and the overweight group had a lower risk of serum zinc deficiency than the normal group(OR=0. 71, 95%CI 0. 52-0. 96). CONCLUSION: The prevalence of serum zinc deficiency among adults aged 18-60 in China is relatively low. Vitamin A deficiency is a risk factor for zinc deficiency and overweight is a protective factor for zinc deficiency.

An iodine balance study to explore the recommended nutrient intake of iodine in Chinese young adults.

Data on average iodine requirements for the Chinese population are limited following implementation of long-term universal salt iodisation. We explored the minimum iodine requirements of young adults in China using a balance experiment and the 'iodine overflow' hypothesis proposed by our team. Sixty healthy young adults were enrolled to consume a sequential experimental diet containing low, medium and high levels of iodine (about 20, 40 and 60 µg/d, respectively). Each dose was consumed for 4 d, and daily iodine intake, excretion and retention were assessed. All participants were in negative iodine balance throughout the study. Iodine intake, excretion and retention differed among the three iodine levels (P < 0·01 for all groups). The zero-iodine balance derived from a random effect model indicated a mean iodine intake of 102 µg/d, but poor correlation coefficients between observed and predicted iodine excretion (r 0·538 for µg/d data) and retention (r 0·304 for µg/d data). As iodine intake increased from medium to high, all of the increased iodine was excreted ('overflow') through urine and faeces by males, and 89·5 % was excreted by females. Although the high iodine level (63·4 µg/d) might be adequate in males, the corresponding level of 61·6 µg/d in females did not meet optimal requirements. Our findings indicate that a daily iodine intake of approximately half the current recommended nutrient intake (120 µg/d) may satisfy the minimum iodine requirements of young male adults in China, while a similar level is insufficient for females based on the 'iodine overflow' hypothesis.

Breast milk selenocystine as a biomarker for selenium intake in lactating women at differential geographical deficiency risk in China.

BACKGROUND AND OBJECTIVES: A reliable biomarker for optimal selenium (Se) intake in lactating women is not currently available. METHODS AND STUDY DESIGN: Daily dietary Se intake in lactating women was calculated from a 24-hour meal record survey for over 3 days. Se levels in plasma and breast milk were measured through inductively coupled plasma mass spectrometry. Plasma selenoprotein P 1 levels and glutathione peroxidase 3 activity were measured using an enzyme-linked immunosorbent assay. Ultra-performance liquid chromatography-tandem mass spectrometry was used to analyze proteinaceous Se species in enzymatically digested breast milk. RESULTS: Dietary Se intakes of lactating women from Liangshan, Beijing, and Enshi were 41.6±21.2 ng/d, 51.1±22.6 ng/d, and 615±178 ng/d, respectively (p<0.05). The Se levels in the blood and breast milk were significantly associated with the dietary Se intake (p<0.05). The proteinaceous Se species in breast milk were SeMet and SeCys2. The levels of SeMet in the lactating women from Liangshan, Beijing, and Enshi were 3.31±2.44 ng Se/mL, 7.34±3.70 ng Se/mL, and 8.99±9.64 ng Se/mL, while that of SeCys2 were 13.7±12.0 ng Se/mL, 35.6±20.9 ng Se/mL, and 57.4±13.2 ng Se/mL, respectively. Notably, the concentration of SeCys2, the metabolite of unstable SeCys, reached a saturation platform, whereas no similar phenomenon were found for the total Se SeMet from Secontaining proteins. CONCLUSIONS: SeCys2 in breast milk is a potential biomarker for determining the optimal Se intake in lactating women.

[Blood copper, zinc, calcium, magnesium and iron distribution in rural China aged 6-12 in 2002 and 2012].

OBJECTIVE: To investigate the distribution and changes of blood copper, zinc, calcium, magnesium and iron in Chinese rural children aged 6 to 12 years in 2002 and 2012. METHODS: A total of 3420 blood samples were randomly selected from the China Nutrition and Health Survey 2002 and 2012. Metal concentrations in whole blood were determined by inductively coupled mass spectrometry(ICP-MS) after the dilution of 0. 5%(V/V) HNO_3 and 0. 05%(V/V) Triton-X-100. The changes between 2002 and 2012 of blood five elements concentration in children of 6-12 years in rural China were compared. RESULTS: The median of blood levels of copper, zinc, calcium, magnesium and iron in 2002 were 1. 02(95% CI 0. 79-1. 32), 4. 88(95% CI 3. 17-6. 77), 58. 59(95% CI 44. 97-74. 24), 41. 56(95% CI 33. 01-52. 28) and 423. 21(95% CI 338. 83-540. 69) mg/L, respectively. And in 2012, the median values were 1. 00(95% CI 0. 75-1. 31), 5. 12(95% CI 3. 17-7. 37), 63. 36(95% CI 41. 14-79. 16), 41. 78(95% CI 30. 89-52. 53) and 422. 06(95% CI 297. 83-522. 56) mg/L, respectively. There were significant differences in blood copper, zinc, calcium and iron levels in general, gender and age. There were also significant area differences in the distribution of copper, zinc, calcium, magnesium and iron, but the changes were opposite. CONCLUSION: In 2002 and 2012, there were differences in the blood distribution of Cu, Zn, Ca, Mg and Fe of children aged 6-12 in rural China in terms of general, gender, age and area.

Validated ¹H and 13C Nuclear Magnetic Resonance Methods for the Quantitative Determination of Glycerol in Drug Injections.

In the current study, we employed high-resolution proton and carbon nuclear magnetic resonance spectroscopy (¹H and 13C NMR) for quantitative analysis of glycerol in drug injections without any complex pre-treatment or derivatization on samples. The established methods were validated with good specificity, linearity, accuracy, precision, stability, and repeatability. Our results revealed that the contents of glycerol were convenient to calculate directly via the integration ratios of peak areas with an internal standard in ¹H NMR spectra, while the integration of peak heights were proper for 13C NMR in combination with an external calibration of glycerol. The developed methods were both successfully applied in drug injections. Quantitative NMR methods showed an extensive prospect for glycerol determination in various liquid samples.

[Assessment of iodine nutritional status for pregnant women using adjusted urine creatinine from spot and 24-hour urine].

OBJECTIVE: To establish a reliable method of iodine nutritional assessment for pregnant women using the adjusted urinary creatinine of spot urine and 24-hour urine samples. METHODS: The spot urine in the morning at 8 00-11:30 and the following 24-hour urine samples of pregnant women were collected in Peking Union Medical College Hospital during March to October in 2016. The urinary iodine and urinary creatinine concentrations were determined. The estimated 24-hour urinary iodine excretion( 24-h UIE) was calculated using the urinary iodine/urinary creatinine( UIC/Cr) ratio of spot urine, and 24-hour urinary creatinine excretion( 24-h UCr E). RESULTS: There was a significant difference in the UIC, UIC/Cr ratio between spot urine and 24-h urine( P <0. 05). The UIC, UIC/Cr ratio of spot urine, and the estimated 24-h UIE all were significantly correlated with the real 24-h UIE( P < 0. 01), especially the estimated 24-h UIE were taking up 70%-80% for the real 24-h UIE in the period of gestation. CONCLUSION: The UIC, UIC/Cr, and the estimated 24-h UIE cannot directly replace the relevant values derived of the 24-hour urine samples. But the estimated 24-h UIE can reflect the iodine nutritional status of pregnant women in recent days, and the method could be a reliable reference for the iodine nutritional assessment of the pregnant women in practice.

[Serum vitamin D levels of Chinese rural women of childbearing age in 2010-2012].

OBJECTIVE: To obtain the serum 25-hydroxyvitamin D status for women of child-bearing age aged 18-44 years from rural areas in China Health and Nutrition Survey2010-2012( CHNS 2010-2012). METHODS: We randomly selected the 1520 representative women of childbearing age from the 75 monitoring spots derived in the CNHS 2010-2012. The information of study population were collected using questionnaires and the serum 25-hydroxyvitamin D concentration was determinedusing the RIA kits. The vitamin D nutritional status was classified by the standards suggested by the America Endocrine Society. Multiple Logistic regression analysis was explored therelationship between vitamin D status with the potential relevant factors. RESULTS: The median serum 25-hydroxyvitamin D concentration was 22. 7 ng/m L ranged from 8. 2 to42. 0 ng/m L. The prevalence of vitamin D deficiency was 38. 7%, insufficiently 39. 5%and sufficiently 21. 8%. Multiple Logistic regression analysis showed that nationality, geographical regions and income per capita was the significant. CONCLUSION: s The nutritional status of vitamin D in women of child bearing-age is not better in the CNHS2010-2012. We suggest that it should be pay more attention on the women of childbearing age for the minority, north China, family income per year between 10000 and 30000 Yuan.

[Production effect comparison of SEPP and GPx between HepG2 and Hela cells with different selenocompounds].

OBJECTIVE: To compare the effect of several selenocompounds on the productions of SEPP and GPx in HepG2 and Hela cells. METHODS: The cultured HepG2 and Hela cells were divided into the control, Na2SeO3, SeMet and MeSeCys groups. After adding the selected selenocompounds (with the respective concentration 0.01 and 0.1 µmol/L), the experimental groups were then incubated for 48 h and 72 h. Finally, the cell culture supernatants and homogenates were collected for the SEPP and GPx concentrations detection by a double-antibody sandwich enyme-linked immuno-sorbent-assay (ELISA). RESULTS: The SEPP and GPx concentrations in Hela cells treated with 0.1 µmol/L SeMet and MeSeCys were significantly higher than that in the control group (P < 0.05). The SEPP and GPx concentrations in HepG2 cell treated with 0.1 µmol/L selenocompounds were significantly higher than that in Hela cells (P < 0.05). CONCLUSION: HepG2 cells are more beneficial to the production of selenoproteins than Hela cells.