Basal Energy Expenditure of Chinese Healthy Adults: Comparison of Measured and Predicted Values.

OBJECTIVE: This study aimed to measure the basal energy expenditure (BEE) of Chinese healthy adults and establish an accurate predictive equation for this population. METHODS: In total, 470 Chinese healthy adults had their BEE measured using the Cosmed K4b 2 portable metabolic system. Multiple linear regression analysis was applied to develop new optimal equations for predicting BEE. The bias, accuracy rate, concordance correlation coefficient (CCC), and root mean square error (RMSE) were used to evaluate the accuracy of the predictive equations. RESULTS: There was a significant difference in BEE between males and females, with 5,954 kJ/d and 5,089 kJ/d, respectively. People living in rural areas expended significantly higher BEE (5,885 kJ/d) than those in urban areas (5,279 kJ/d). Previous equations developed by Henry, Schofield, Harris-Benedict (H-B), and Liu overestimated the BEE of Chinese healthy adults. The new equations derived from the present study displayed the smallest average bias and RMSE from the measured basal energy expenditure (mBEE). The CCC of the new equations was higher than other predictive equations, but it was lower than 0.8. There was no significant difference in the accuracy rate among all predictive equations. CONCLUSIONS: Sex and regional differences in BEE were observed in Chinese healthy adults. Neither the widely used previous predictive equations nor the one derived in the present study were accurate enough for estimating the BEE of Chinese healthy adults. Further study is required to develop more accurate equations for predicting the BEE of Chinese healthy adults aged between 20-45 years.

Total energy expenditure of 16 Chinese young men measured by the doubly labeled water method.

OBJECTIVE: Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. METHODS: Sixteen healthy young men age 23±1 years with body mass index 22.0±1.4 kg/m2 were recruited. TEE was measured by the DLW method, and basal energy expenditure (BEE) was determined by indirect calorimetry. We also conducted 24-h activity, energy balance and factorial approach to estimate energy requirements of the subjects. RESULTS: TEE of subjects by DLW method was 9.45±0.57 MJ/day (2258±180 kcal/day). The 24-h activity was 10.80±0.33 MJ/day (2582±136 kcal/day). The energy requirement, derived from energy balance observations, was 9.93±1.32 MJ/day (2373±315 kcal/day). The BEE of 6.65±0.28 MJ/day (1589±67 kcal/day), calculated by the adjusted Schofield equation, was significantly higher (P<0.001) than that measured by indirect calorimetry, 5.99±0.66 MJ/day (1433±158 kcal/day). The TEE derived from the factorial approach was 10.31±0.43 MJ/day (2463±104 kcal/day). CONCLUSION: The TEE of Chinese young men measured by the DLW method was about 10% lower than the current recommended nutrient intake (RNI), suggesting that the RNI for Chinese men maybe overestimated. Further studies are warranted to determine the value of the estimated energy requirement.

[Characteristics and adaptation of seasonal drought in southern China under the background of climate change. V. Seasonal drought characteristics division and assessment in southern China].

Zoning seasonal drought based on the study of drought characteristics can provide theoretical basis for formulating drought mitigation plans and improving disaster reduction technologies in different arid zones under global climate change. Based on the National standard of meteorological drought indices and agricultural drought indices and the 1959-2008 meteorological data from 268 meteorological stations in southern China, this paper analyzed the climatic background and distribution characteristics of seasonal drought in southern China, and made a three-level division of seasonal drought in this region by the methods of combining comprehensive factors and main factors, stepwise screening indices, comprehensive disaster analysis, and clustering analysis. The first-level division was with the annual aridity index and seasonal aridity index as the main indices and with the precipitation during entire year and main crop growing season as the auxiliary indices, dividing the southern China into four primary zones, including semi-arid zone, sub-humid zone, humid zone, and super-humid zone. On this basis, the four primary zones were subdivided into nine second-level zones, including one semi-arid area-temperate-cold semi-arid hilly area in Sichuan-Yunnan Plateau, three sub-humid areas of warm sub-humid area in the north of the Yangtze River, warm-tropical sub-humid area in South China, and temperate-cold sub-humid plateau area in Southwest China, three humid areas of temperate-tropical humid area in the Yangtze River Basin, warm-tropical humid area in South China, and warm humid hilly area in Southwest China, and two super-humid areas of warm-tropical super-humid area in South China and temperate-cold super-humid hilly area in the south of the Yangtze River and Southwest China. According to the frequency and intensity of multiple drought indices, the second-level zones were further divided into 29 third-level zones. The distribution of each seasonal drought zone was illustrated, and the zonal drought characteristics and their impacts on the agricultural production were assessed. Accordingly, the drought prevention measures were proposed.

[Pilot study on total energy expenditure by accelerometer and physical activity logs].

OBJECTIVE: Using accelerometer and physical activity logs to evaluate daily energy expenditure, as to providing a simple and convenient method to survey the total energy expenditure (TEE). METHODS: The different activity intensities recorded by accelerometer were distinguished into a certain different energy expenditure value by gas metabolism method. Forty-one participants wore the accelerometer for 7 days continuously and completed physical activity logs everyday at the same time. The total energy expenditure was evaluated by these methods. RESULTS: Total energy expenditure evaluated by accelerometer was (9761 +/- 866) kJ/d [(2332 +/- 207) kcal/d, PAL 1.46 +/- 0.11] for male and (7526 +/- 879) kJ/d [ (1798 +/- 210) kcal/d,P AL 1.43 +/- 0.09 for female; whereas combining accelerometer and physical activity logs data showed that the total energy expenditure was (10 573 +/- 804) kJ/d [(2526 +/- 192) kcal d, PAL 1.58 +/- 0.10] for male, and 8191 +/- 737 kJ/d [(1957 +/- 176) kcal/d, PAL 1.56 +/- 0.08] for female. CONCLUSIONS: Using accelerometer and physical activity logs to evaluate the total energy expenditure might be consistent with the existing data, so this method might be used to survey the individual energy expenditure and physical activity levels.

[Energy expenditure in reading and watching TV studied on 30 young females].

OBJECTIVE: To measure the energy expenditure of reading and watching TV for young women. METHODS: All 30 girls in the college were selected according to questionnaire, medical examination, blood test, liver function and thyroid gland level. Energy expenditure of reading and watching TV was measured respectively by the Cosmid K4b2 portable gas analysis system from Italy. Basic metabolic rate (BMR) and resting metabolic rate (RMR) were measured as to analyzing results conveniently. RESULTS: The energy expenditure in reading was (226.35 +/- 56.07) kJ/h and the heart rate was (69 +/- 5) bmp. For watching TV it was (220.79 +/- 65.69) kJ/h and the heart rate was (68 +/- 5) bmp. BMR was (178.53 +/- 53.51) kJ/h and the heart rate was (62 +/- 6) bmp. RMR was (214.76 +/- 44.56) kJ/h and the heart rate was (65 +/- 6) bpm. CONCLUSIONS: The energy expenditure in reading should be higher than that of watching TV, however, the difference was not obvious. The expenditure rates might get closer to those of RMR. It might be regarded as an expenditure of very light physical active in Chinese.

[Comparison of bioelectrical impedance analysis and isotope dilution method in assessment of body composition].

OBJECTIVE: To determine the validity of bioelectrical impedance analysis (BIA) in measuring body composition and to compare with the reference stable isotope dilution method. METHODS: According to the data from 150 students of Bethune Military Medical College, 16 female young adults with normal BMI were selected as the participants. The experimental period was 14 days. During the experimental period, the subjects were centralized on management. At the first day of the period, double labeled water was given to the subjects orally. The urine collection time-points were 2h, 4h, 6h, 8h and the 2nd to 14th day after the administration of isotope dose. All isotope measurements were made by using an isotope ratio mass spectrometer. From the isotope curing curve, the indexes of body composition were gained. At the same time, the body compositions were also measured by using BIA method every day (3 hours after dinner). The paired t test and Pearson correlations were used to measure the significance and the degree of correlation between the measurements determined by using the two methods. RESULTS: There were no significant differences between the measurements determined by using the two methods. TBW, FFM, BF and BF% measured with the BIA method were significantly correlated with those measured by using the isotope method (r = 0.556, 0.556, 0.817 and 0.606 respectively). CONCLUSION: BIA might provide an accurate and reliable assessment in body composition of the healthy Chinese adults.

[Comparison of assessment of food intakes by using 3 dietary survey methods].

OBJECTIVE: To analyze the difference and correlation of food intakes assessed by Food Weighted Record, 24 Hours Recall and Food Frequency Questionnaire (FFQ) methods. SUBJECTS: The data of 2002 China National Nutrition and Health Survey were used. All 23,198 subjects (male 11,107, female 12,091) finished all three dietary survey methods. Food Weighted Record method weighted all food items consumed at home by all family members in last 3 days; 24 Hours Recall recorded all food items the subjects consumed at and out home in last 3 days; FFQ recorded the main 33 categories food items that the subjects consumed at and out home in last year. RESULTS: Compared to Food Weighted Record method, food intakes assessed by 24 hours recall were similar, and the relative differences were less than 10% of most food items. The proportion of over-report and under-report (+/- 25%) by 24 Hours Recall were less than 40%. The correlation coefficients of food intakes between Food Weighted Record and 24 Hours Recall methods ranged from 0.58 to 0.88. The results from Food Weighted Record and FFQ were similar among the high frequently consumed food items. The relative differences of the food intakes investigated between Food Weighted Record and FFQ were less than 15% and the proportion of over-report and under-report (+/- 25%) by FFQ were more than 50%. The correlation coefficients of food intakes between Food Weighted Record and FFQ ranged from 0.08 to 0.76. CONCLUSION: Food intakes might be assessed accurately by the Food Weighted Record revised 24 Hours Recall method, and FFQ method be also used to assess the food intakes, especially for the frequently consumed food items, as to studying the relationship between food consumption and health.

[Assessment of the BALB/c mice as a suitable animal model for the investigation of food allergy].

OBJECTIVE: This study was to develop a suitable model for the investigation for food allergy. METHODS: BALB/c mice were dosed by intraperitoneally with Ovalbumin, Beef serum albumin, Trypsin inhibitor and Potato acid phosphatase respectively (0.25ml 20mg/mnl) on day 0 and again on day 7. Control group was dosed with PBS. Sera form individual animals were analysed for specific IgE and Passive cutaneous anaphylaxis tests. Additionally, the level of histamine in plasma were detected. RESULTS: The high titres of specific IgE (1: 32) could be provoked in test groups compared with control group. In addition, the level of histamine in plasma of test groups was higher than that in the control group. But there was no statistical significance between group food allergen and group Potato acid phosphatase. CONCLUSION: Although allergic action of BALB/c mice could be provoked, the situation of the allergic action of BALB/c mice to the proteins was very different with the human being. The BALB/c mice could not be a suitable model for the investigation for food allergy.

[Strategies for safety assessment of genetically modified crops: current and future development].

Gene recombinant technologies supply agriculture product with great vitality. But the risk of genetically modified crops cannot be ignored. The international organizations such as WHO, FAO and OECD have reached common agreement: the safety of transgenic crops should be thoroughly evaluated based on "substantial equivalence"principle. The relevant strategies including: substantial equivalent analysis, toxic tests, protein allergenic study, nutritional assessment, etc. With the development of new technologies, the approaches of genomic, proteomics, metabolomics would be applied to detect the unintended effects. The EU recently adopted legislation on the cultivation GM crops requiring the post market surveillance for any unanticipated adverse effects in the long term. In conclusion, the strategies of the safety assessment of GM crop are very strict and likely development.

Predicting membrane protein types using residue-pair models based on reduced similarity dataset.

An algorithm to predict the membrane protein types based on the multi-residue-pair effect in the Markov model is proposed. For a newly constructed dataset of 835 membrane proteins with very low sequence similarity, the overall prediction accuracy has been achieved as high as 81.1% and 71.7% in the resubstitution and jackknife test, respectively, for a prediction of type I single-pass, type II single-pass, multi-pass membrane proteins, lipid chain-anchored and GPI-anchored membrane proteins. The improvement of about 11% in the jackknife test can be achieved compared with the component-coupled algorithm merely based on the amino acid composition (AAC approach). The improvement is also confirmed on a high similarity dataset and the other extrapolating test. The result implies that designing more incisive analysis tools, one should develop algorithms based on the representative dataset with lower sequence similarity. The present algorithm is useful to expedite the determination of the types and functions of new membrane proteins and may be useful for the systematic analysis of functional genome data in a large scale. The computer program is available on request.