Effects of a comprehensive nutrition education programme to change grade 4 primary-school students' eating behaviours in China.

OBJECTIVE: As part of a national initiative to reduce child obesity, a comprehensive school-based nutrition education intervention to change eating behaviours among grade 4 primary-school students was developed, implemented and evaluated. DESIGN: The intervention was developed by school staff, with technical assistance from outside health education specialists. The programme included school facility upgrades, school teacher/staff training, curriculum changes and activities for parents. Student scores on nine key eating behaviours were assessed prior to and after the programme. The quality of programme implementation in the schools was monitored by technical assistance teams. SETTING: Shandong Province (high household income) and Qinghai Province (low household income), China. Three programme schools and three control schools in each province.ParticipantsStudents in grade 4 (age 8-9 years). RESULTS: There were significant positive changes in self-reported eating behaviour scores from pre- to post-assessment in programme schools. At post-test students in programme schools had significantly higher scores than students in control schools after controlling for other variables. The programme was more effective in the high-income province. Observations by the technical assistance teams suggested the programme was implemented more completely in Shandong. The teams noted the challenges for implementing and evaluating programmes like these. CONCLUSIONS: This intervention increased healthy eating behaviours among 4th graders in both provinces and had more effect in the more affluent province. Results suggest that a scaled-up initiative using existing school and public health resources could change eating practices in a large population over time. The intervention also provided lessons for implementing and evaluating similar nutrition programmes.

Effects of selected socio-demographic characteristics on nutrition knowledge and eating behavior of elementary students in two provinces in China.

BACKGROUND: National and international child health surveys have indicated an increase in childhood obesity in China. The increase has been attributed to a rising standard of living, increasing availability of unhealthy foods, and a lack of knowledge about healthy diet. The objective of this study was to assess the effect of selected socio-demographic characteristics on the BMI, nutrition knowledge, and eating behavior of elementary school children. METHODS: Multistage stratified cluster sampling was used. Information on demographics, nutrition knowledge, and eating behavior was gathered by means of questionnaires. The schools' doctors provided the height and weight data. The study was set in one economically advantaged and one economically disadvantaged province in China. The participants were Grade 3 students, ages 8-10 years (N = 3922). RESULTS: A cluster analysis identified four socio-demographic variables distinguished by parental education and family living arrangement. A one-way ANOVA compared differences among the clusters in BMI, child nutrition knowledge, and child eating behavior. Students in the cluster with lowest parent education level had the lowest nutrition knowledge scores and eating behavior scores. There was no significant benefit from college education versus high school education of parents in the other three clusters. BMI was not affected by parent education level. CONCLUSION: The nutrition status of elementary school age children will benefit most by increasing the general level of education for those adults who are presently least educated.

Relationships of health literacy, health behavior, and health status regarding infectious respiratory diseases: application of a skill-based measure.

This study aimed to explain the relationships among health literacy, health behavior, and health status, using a newly developed skills-based measure of health literacy regarding respiratory infectious diseases. This instrument was designed to measure individuals' reading, understanding, and calculating ability, as well as their oral communication and Internet-based information-seeking abilities. A pilot survey was conducted with 489 residents in Beijing, China, to test the reliability and validity of the new measure. Next, a larger study with 3,222 residents in three cities with multistage stratified cluster sampling was implemented to validate a latent variable model (goodness of fit index=0.918, root mean square residual=0.076). In this model higher educational attainment (ß=0.356) and more health knowledge (ß=0.306) were positively and directly associated with greater health literacy skill, while age was negatively associated with it (ß=-0.341). Age (ß=0.201) and health knowledge (ß=0.246) had positive and direct relationship with health behavior, which was, in turn, positively associated with health status (ß=0.209). The results illustrate the complex relationships among these constructs and should be considered when developing respiratory intervention strategies to promote health behavior and health status.

Measuring health literacy regarding infectious respiratory diseases: a new skills-based instrument.

BACKGROUND: There is no special instrument to measure skills-based health literacy where it concerns infectious respiratory diseases. This study aimed to explore and evaluate a new skills-based instrument on health literacy regarding respiratory infectious diseases. METHODS: This instrument was designed to measure not only an individual's reading and numeracy ability, but also their oral communication ability and their ability to use the internet to seek information. Sixteen stimuli materials were selected to enable measurement of the skills, which were sourced from the WHO, China CDC, and Chinese Center of Health Education. The information involved the distribution of epidemics, immunization programs, early symptoms, means of disease prevention, individual's preventative behavior, use of medications and thermometers, treatment plans and the location of hospitals. Multi-stage stratified cluster sampling was employed to collect participants. Psychometric properties were used to evaluate the reliability and validity of the instrument. RESULTS: The overall degree of difficulty and discrimination of the instrument were 0.693 and 0.482 respectively. The instrument demonstrated good internal consistency reliability with a Cronbach's alpha of 0.864. As for validity, six factors were extracted from 30 items, which together explained 47.3% of the instrument's variance. And based on confirmatory factor analysis, the items were grouped into five subscales representing prose, document, quantitative, oral and internet based information seeking skills (χ(2) = 9.200, P>0.05, GFI = 0.998, TLI = 0.988, AGFI = 0.992, RMSEA = 0.028). CONCLUSION: The new instrument has good reliability and validity, and it could be used to assess the health literacy regarding respiratory infectious disease status of different groups.

Determinants of health literacy and health behavior regarding infectious respiratory diseases: a pathway model.

BACKGROUND: Health literacy has been defined as the degree to which individuals have the capacity to obtain, process, and understand the basic health information and services needed to make appropriate health decisions. Currently, few studies have validated the causal pathways of determinants of health literacy through the use of statistical modeling. The purpose of the present study was to develop and validate a health literacy model at an individual level that could best explain the determinants of health literacy and the associations between health literacy and health behaviors even health status. METHODS: Skill-based health literacy test and a self-administrated questionnaire survey were conducted among 3222 Chinese adult residents. Path analysis was applied to validate the model. RESULTS: The model explained 38.6% of variance for health literacy, 11.7% for health behavior and 2.3% for health status: (GFI = 0.9990; RMR = 0.0521; χ(2) = 10.2151, P = 0.1159). Education has positive and direct effect on prior knowledge (ß = 0.324) and health literacy (ß = 0.346). Health literacy is also affected by prior knowledge (ß = 0.245) and age (ß = -0.361). Health literacy is a direct influencing factor of health behavior (ß = 0.101). The most important factor of health status is age (ß = 0.107). Health behavior and health status have a positive interaction effect. CONCLUSION: This model explains the determinants of health literacy and the associations between health literacy and health behaviors well. It could be applied to develop intervention strategies to increase individual health literacy, and then to promote health behavior and health status.

[Status of knowledge and behaviors about chronic diseases prevention for Chinese residents in 2008].

OBJECTIVE: To learn the status of knowledge and behaviors about chronic diseases prevention for Chinese residents, and to provide basis for developing health education strategy. METHODS: Using multi-stage stratified random cluster sampling, 79 542 residents aged 15-69 years old from 31 provinces (municipalities and autonomous regions) and Xinjiang Production and Construction Corps in Mainland China were investigated with the questionnaire of chronic diseases prevention. RESULTS: There were 78 429 valid questionnaires recovered. The effective questionnaire return rate reached 98.60%. For some questions such as how to face second hand smoking, diseases types caused by second hand smoking, milk daily intake, drink daily intake for adult and the correct cognition to weight control, the correct rates were all below 30%. There were only 3.87% respondents possessed knowledge and behaviors about chronic diseases prevention. The proportion possessed knowledge and behavior about chronic diseases prevention of the urban population was higher than that of the rural population. The proportion of respondents aged from 35 to 45 was higher than that of other respondents. The higher were educational levels, the higher was the proportion. These differences had all statistical significance (P < 0.01). CONCLUSION: The proportion possessed knowledge and behavior about chronic diseases prevention of respondents was low, especially to some specific prevention measurement such as how to control salt daily intake. In future, different health education strategies about chronic diseases prevention should be developed for different population.

Molecular mechanism of icariin on rat asthmatic model.

BACKGROUND: Effects of icariin on airway inflammation in asthmatic rats and the intervention of LPS induced inflammation are interfered with the machanism of icariin. Our study aimed to observe the effect of icariin on ovalbumin-induced imbalance of Th1/Th2 cytokine expression and its mechanism. METHODS: Sixty male SD rats were randomly divided into control group (PBS), asthma group (ovalbumin (OVA)-induced), dexamethasone group, and OVA+icariin low, medium and high dose groups (5, 10, 20 mg/kg, respectively). Each group had ten rats. The model of OVA sensitization was a rat asthma model. Enzyme-linked immunosorbent assay (ELISA) method was used to observe the effects of icariin on interleukin-4 (IL-4) and inerferon γ (IFN-γ) in rats' lung tissue. Immunohistochemical staining was applied to detect the intervention effects of icariin on T cells (T-bet) and gatabinding protein 3 (GATA-3) in rat pulmonary tissue. Realtime RT-PCR was used to observe the intervention effects of icariin on T-bet and GATA-3 mRNA expression in rat pulmonary tissue and spleen lymphocytes. Western blotting was used to observe the icariin intervention effects on T-bet, GATA-3 and nuclear factor-Kappa B (NF-κB) p65 protein expressions in rat pulmonary tissue. RESULTS: The ELISA results from pulmonary tissue showed that IL-4 expression was significantly reduced (P < 0.05), while the IFN-γ expression increased but not significantly when we compared OVA+icariin medium and high dose groups with the asthma group. Immunohistochemical staining of pulmonary tissue showed that the GATA-3 decreased significantly while the T-bet staining did not change in the OVA+icariin high dose group. In pulmonary tissue and spleen lymphocytes T-bet and GATA-3 mRNA expressions were significantly reduced (P < 0.05) in icariin treatment groups compared with the asthma model group. GATA-3 and T-bet mRNA in rat spleen lymphocytes in the asthma group were higher than in the control group. GATA-3 mRNA expression in pulmonary tissue significantly decreased (P < 0.05) while T-bet mRNA expression decreased but not significantly in the icariin treatment group compared with the asthma group. T-bet and GATA-3 protein expressions in pulmonary tissue increased significantly compared with the asthma group, which meant that icariin could inhibit the increase of GATA-3 protein, but not of T-bet. The bronchus, blood vessels and periphery pulmonary tissue had infiltration of inflammatory cells in the OVA+icariin high dose group while NF-κB p65 cells were reduced, and expression of NF-κB p65 in this group was less than in the asthma group. The expression of total p65 protein decreased with icariin treatment while the expression of cytoplasmic p65 protein increased. CONCLUSIONS: Icariin could regulate the imbalance of Th1/Th2 cytokines in asthmatic rat pulmonary tissue. Icariin could regulate the imbalance of Th1/Th2 associated transcription factors T-bet and GATA-3 in asthmatic rat pulmonary tissue and spleen lymphocytes. Icariin could inhibit the activation of NF-κB p65 protein in asthmatic rat pulmonary tissue.

Calcium supplementation for 2 years improves bone mineral accretion and lean body mass in Chinese adolescents.

OBJECTIVE: to study the effects of different doses of calcium intake on bone health and body composition in Chinese adolescents. METHODS: a double-blind randomized controlled trial of calcium carbonate supplementation in 257 healthy adolescents aged 12-15 years old for 24 months. Subjects were randomly assigned to four groups receiving chewable calcium carbonate tablets providing elemental calcium at 63 mg/d, 354 mg/d, 660 mg/d, 966 mg/d, respectively. At the end of intervention, we reclassified 197 adolescents into 3 groups who had received actual doses of elemental calcium of 85 mg/d (Low dose), 230 mg/d (Medium dose) and 500 mg/d (High dose). We measured bone mineral content (BMC), bone mineral density (BMD) and body composition by dual-energy X-ray absorptiometry. RESULTS: BMC and BMD of total body and lumbar spine were increased significantly in both males and females after intervention at all doses (p<0.05). In males, after supplementation, total body BMC in the medium and high dose groups (2464 g and 2437 g, respectively) was significantly higher than that in the low dose group (2321 g) after adjusting for age, pubertal development, BMI, physical activity and energy intake; in addition, lean body mass in the medium and high dose groups (49.1 kg and 48.8 kg, respectively) was significantly higher than that in the low dose group (46.7 kg) (p<0.05). There was no significant effect of calcium supplementation on bone mass or body composition in females. CONCLUSIONS: calcium supplementation more than 230 mg/d for two years can improve bone mineral accretion and lean body mass in Chinese male adolescents.

[Spectral characteristics analysis and remote sensing inversion of water quality parameters in Han Shiqiao wetland].

The research object of the present paper is the water quality of Han Shiqiao wetland water. Water spectrum and quality parameters were measured on the site and in the lab. The authors simulated the relationships between water quality parameters and the best bands or combination, and built the multiple linear regression equation to obtain characteristic spectrum of the key water quality parameters. Besides, several key issues involved in applying ASTER satellite imagery to water quality include atmospheric correction, discussing methods for ASTER data bands analysis, and choosing the best bands and band combination. Results indicated that although the simulation model is not universal, the analysis of spectral characteristics based on ground spectrometer could provide foundations for the choice of remote sensing characteristics bands. The band ratio of water quality parameters simulated from ASTER spectral characteristics moves to relatively long-wave band. Finally, based on the analysis of ASTER remote sensing characteristics bands, the authors built water quality parameters regression model. The models for water quality parameters were recommended, and the accuracies of these models were analyzed. Making use of regression model, we executed spatial distribution map of water quality parameters to achieve wetland water monitoring with remote sensing in terms of variation in space and with time.

Factors affecting calcium balance in Chinese adolescents.

Chinese dietary reference intakes (DRIs) for calcium were developed mainly from studies conducted amongst Caucasians, yet a recent review showed that reference calcium intakes for Asians are likely to be different from those of Caucasians (Lee and Jiang, 2008). In order to develop calcium DRIs for Chinese adolescents, it is necessary to explore the characteristics and potential influencing factors of calcium metabolic balance in Chinese adolescents. A total of 80 students (15.1+/-0.8 years) were recruited stratified by gender from a 1-year calcium supplementation study. Subjects were randomly designed to four groups and supplemented with calcium carbonate tablets providing elemental calcium at 63, 354, 660, and 966 mg/day, respectively. Subjects consumed food from a 3-day cycle menu prepared by staff for 10 days. Elemental calcium in samples of foods, feces, and urine was determined in duplicates by inductively coupled plasma atomic emission spectrometry. The total calcium intake ranged from 352 to 1323 mg/day. The calcium apparent absorption efficiency and retention in boys were significantly higher than that in girls (68.7% vs. 46.4%, 480 mg/day vs. 204 mg/day, P<0.05). Calcium retention increased with calcium intakes, but did not reach a plateau. Calcium absorption efficiency in boys increased with calcium intake up to 665 mg/day, and decreased after that. In girls, calcium absorption efficiency decreased with calcium intake. Calcium absorption efficiency increased within 1 year after first spermatorrhea in boys, but decreased with pubertal development in girls. Sex, calcium intake, age, and pubertal development were the most important determinants of calcium absorption (R(2)=0.508, P<0.01) and retention (R(2)=0.745, P<0.05). This study indicates that sex, calcium intake, age, and pubertal development are important factors for calcium retention and absorption during growth, which should be considered for the development of calcium DRIs for Chinese adolescents.

Interactions between effects of estrogen receptor gene polymorphisms on BMD and experiences of the first spermorrhea in Chinese Han boys.

OBJECTIVE: To study the interaction between polymorphisms of estrogen receptor (ER) gene and puberty on bone mineral density (BMD). METHODS: One hundred and forty-six boys aged 13-17 years were divided into two groups according to their first spermorrhea. DNA was analyzed for Xba I and Pvu II genotypes by PCR-RFLP. BMD of the total body, forearm and lumbar spine was measured by dual-energy X-ray absorptiometry (DXA). The relationship between polymorphisms of ER gene and BMD in these two groups was analyzed. RESULTS: The BMD at all sites in the spermorrhea group was significantly higher than that in the un-spermorrhea group. The independent contribution of ER genotypes to BMD at two pubertal stages was analyzed after adjusting co-variables. In the un-spermorrhea group, the BMD at distal 1/10 and 1/3 forearm of those carrying pp genotype was significantly higher than that of the non-carries, whereas in the spermorrhea group BMD in those carrying the same genotype was significantly lower than that in the non-carriers. Similar results were obtained by haplotype analysis. Multiple stepwise regression analysis showed that body weight, age and the first spermorrehea were the dominant determinants for BMD. BMD at forearm might be influenced by interaction between ER genotype and the first spermorrehea. CONCLUSION: The polymorphisms of ER gene play a different role in BMD influenced by the first spermorrhea. Chinese boys carrying p or x allele should pay more attention to their bone mass.

[Effect of calcium supplementation on absorption rates of zinc and iron in 12-17 years old adolescents].

OBJECTIVE: To study the effect of calcium supplementation on absorption rate of zinc and iron by calcium metabolic balance study. METHODS: A total of 80 students (12-17 years old) were selected randomly from 320 subjects who had been supplemented with calcium supplementation for one year. 10 boys and 10 girls were randomly selected from each calcium supplementation group to attend a 10-day metabolic balance study. Samples of foods, feces and urine were collected. Calcium, zinc and iron in samples were measured with ICP-AES. RESULTS: There were significant differences of calcium intake, but were no differences of iron and zinc intake for 4 groups. The apparent absorption rate of calcium, iron and zinc in boys and girls were 69.4%, 12.5%, 29.9% and 46.4%, 20.9%, 35.3%, respectively. Absorption rates of iron were associated with pubertal stages. There were no significant differences of absorption of calcium, iron and zinc for 4 groups. Apparent absorption rates of calcium, iron and zinc seemed higher (75.3%, 23.2% and 36.4%) when the level of calcium intake were 600 - 800mg/d in boys. CONCLUSION: There were no significant effects on absorption rate of iron and zinc when the level of calcium intake was 1400mg/d in 12-17 years old Chinese adolescents. Absorption rates of calcium, iron and zinc seemed higher when the level of calcium intake was 600 - 800mg/d in boys.

[The relation between body mass index and percentage body fat among Chinese adolescent living in urban Beijing].

OBJECTIVE: To study the relation between body mass index (BMI) and percentage body fat (PBF) in Chinese adolescent, and to compare the prevalence of overweight and obesity using BMI or PBF standards. METHODS: BMI from 757 girls with an average aged of 10.1 years in the rural areas, 165 girls average aged 13.5 years in suburbs and 172 boys average aged 13.7 years in suburb of Beijing, were measured. Their body compositions were also measured by dual-energy X-ray absorptiometry (DEXA). RESULTS: BMI was found closely correlated with PBF in each age group of rural and suburb girls and suburb boys with the correlation coefficient(r) of 0.59 - 0.83. When age, height and pubertal development were controlled, r became 0.54 - 0.88. The prevalence rates of obesity in rural girls, suburb girls and suburb boys were 33.1%, 21.8% and 21.5%, when PBF cutoff values (girls: PBF >or= 35%, boys: PBF >or= 25%) were used. However, the rates became 2.4%, 3.0% and 4.0% when BMI cutoff values of International Obesity Task Force (IOTF) were used. Compared with PBF cutoff values for obesity, the IOTF recommended BMI cutoff values had relatively lower sensitivity (7.3% - 18.9%) and higher specificity (100%). CONCLUSION: BMI correlated well with PBF in Beijing adolescent. IOTF-BMI cutoff values showed low sensitivity and high specificity to Chinese adolescent which might be suitable for identifying obesity but not for the purpose of screening.