2007 Vol. 20, No. 1

Special Focus on
Report on Childhood Obesity in China (4) Prevalence and Trends of Overweight and Obesity in Chinese Urban School-age Children and Adolescents, 1985-2000
2007, 20(1): 1-10.
Objective To describe the nationwide prevalence of childhood overweight/obesity, and their group variations and trends over the past 20 years in the Chinese urban population. Methods Data sets of boys and girls at the age of 7-18 years collected from the series of Chinese national surveillance on students' constitution and health (CNSSCH) between 1985 and 2000 were divided into five socioeconomic and demographic groups, while BMI classification reference proposed by Working Group on Obesity in China (WGOC) was used as screening reference to calculate the prevalence and trends of overweight/obesity in these groups. Results In 2000, the prevalence of obesity and overweight in boys aged 7-18 years was 11.3% and 6.5% in Beijing, 13.2% and 4.9% in Shanghai, 9.9% and 4.5% in coastal big cities, and 5.8% and 2.0% in coastal medium/small-sized cities, respectively, while the prevalence of of obesity and overweight in girls of the same age group was 8.2% and 3.7% in Beijing, 7.3% and 2.6% in Shanghai, 5.9% and 2.8% in coastal big cities, and 4.8% and 1.7% in coastal medium/small-sized cities, respectively. The prevalence of obesity was low in most of the inland cities at an early stage of epidemic overweight. The epidemic manifested a gradient distribution in groups, which was closely related to socioeconomic status (SES) of the study population. However, a dramatic and steady increasing trend was witnessed among all sex-age subgroups in the five urban groups, and such a trend was stronger in boys than in girls, and much stronger in children than in adolescents. Conclusion Although China is at an early stage of epidemic obesity by and large, the prevalence of obesity in her urban population, particularly in coastal big cities has reached the average level of developed countries. The increasing trend has been rapid since early 1990s, and the increments in obesity and overweight are exceptionally high. The prospect of epidemic obesity in China is in no way optimistic. Therefore, preventive program should be focused on the improvement of the balance between caloric intake and energy expenditure, and interventions aimed at changing children's life styles.
Report on Childhood Obesity in China (5) Body Weight, Body Dissatisfaction, and Depression Symptoms of Chinese Children Aged 9-10 Years
2007, 20(1): 11-18.
Objective To investigate the relationship between body weight, body dissatisfaction and depression symptoms among Chinese children. Methods The fasting body weight and height of the third and fourth grade students (n=3886, aged 9 or 10years) from 20 schools in Beijing, China, were measured, and the students were asked to choose the figures of body image and to complete the self-reported children's depression inventory (CDI) questionnaire. Results The CDI Cronbach's alpha was 0.81. The total CDI score was 9.60±7.50, 13.2% of children (boys 16.7% vs girls 9.5%) were at risk of developing depression symptoms. Overweight girls, but not boys, had significantly higher total CDI score than their normal weight counteparts. Both obese girls and boys showed a higher negative self-esteem score. More than one fifth underweight girls still wanted to be thinner while more than one third obese boys still wanted to be heavier. Children who wanted to be thinner showed slightly higher scores of ineffectiveness and negative self-esteem. After introducing the body dissatisfaction into the model, overweight was still associated with total CDI score among girls and obesity was still associated with negative self-esteem among both boys and girls. Conclusion Overweight girls show a significantly higher depression symptom score than their normal weight counterparts, which maybe partially explained by body dissatisfaction. Obese boys and girls are both more likely to suffer from low self-esteem, which is partially explained by body dissatisfaction.
Report on Childhood Obesity in China (6) Evaluation of a Classroom-based Physical Activity Promotion Program
2007, 20(1): 19-23.
Objectives To evaluate the effect of Happy 10 program on the promotion of physical activity, physical growth and development of primary-school students, and on obesity control and prevention. Methods Two similar primary schools from one district of Beijing, China were selected, one as an intervention school and the other as a control school. Happy 10program was implemented at least once every school day in the intervention school for two semesters, whereas no intervention was adopted in the control school. The information on energy expenditure and duration of physical activity was collected by a validated 7-day physical activity questionnaire. Height and weight were measured by trained investigators following the standardized procedure. Energy expenditure and intensity of each Happy 10 session was measured by a physical activity monitor. Results The average energy expenditure and duration of total physical activity per day among students in the intervention school increased significantly from 15.0 to 18.2 kcal/kg, and 2.8 to 3.3 h respectively, whereas the figures significantly decreased in the control school. There was a significant difference in change of weight and BMI between girls in the intervention and control school (2.4 kg vs 4.6 kg, -0.47 kg/m2 vs 0.66 kg/m2). The prevalence of overweight and obesity in the intervention school decreased by 0.4%-5.6%, as compared to the increase by 0.6%-4.5% in the control school. The average energy expenditure and intensity per 10-minute session ranged from 25.0-35.1 kcal, 4.8-6.2 kcal/kg/h respectively in grades 1-5.Conclusion Happy 10 program provides a useful strategy to promote physical activity among school children and also plays a positive role in building up physical growth and development of girls.
Original Articles
Protein Profile of Human Lung Squamous Carcinoma Cell Line NCI-H226
2007, 20(1): 24-32.
Objective To construct a database of human lung squamous carcinoma cell line NCI-H226 and to facilitate discovery of novel subtypes markers of lung cancer. Method Proteomic technique was used to analyze human lung squamous carcinoma cell line NCI-H226. The proteins of the NCI-H226 cells were separated by two-dimensional gel electrophoresis and identified by mass spectrometry. Results The results showed that a good reproducibility of the 2-D gel pattern was attained. The position deviation of matched spots among three 2-D gels was 1.95±0.53 mm in the isoelectric focusing direction,and 1.73±0.45 mm in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis direction. One hundred and twenty-seven proteins, including enzymes, signal transduction proteins, structure proteins, transport proteins, etc. were characterized, of which, 29 identified proteins in NCI-H226 cells were reported for the first time to be involved in lung cancer carcinogenesis.Conclusion The information obtained from this study could provide some valuable clues for further study on the carcinogenetic mechanism of different types of lung cancer, and may help us to discover some potential subtype-specific biomarkers of lung cancer.
Serum Amyloid A Protein: A Potential Biomarker Correlated With Clinical Stage of Lung Cancer
2007, 20(1): 33-40.
Objective To identify serum diagnosis or progression biomarkers in patients with lung cancer using protein chip profiling analysis. Method Profiling analysis was performed on 450 sera collected from 213 patients with lung cancer, 19with pneumonia, 16 with pulmonary tuberculosis, 65 with laryngeal carcinoma, 55 with laryngopharyngeal carcinoma patients,and 82 normal individuals. A new strategy was developed to identify the biomarkers on chip by trypsin pre-digestion. Results Profiling analysis demonstrated that an 11.6kDa protein was significantly elevated in lung cancer patients, compared with the control groups (P<0.001). The level and percentage of 11.6kDa protein progressively increased with the clinical stages Ⅰ-Ⅳ and were also higher in patients with squamous cell carcinoma than in other subtypes. This biomarker could be decreased after operation or chemotherapy. On the other hand, 11.6kDa protein was also increased in 50% benign diseases of lung and 13% of other cancer controls. After trypsin pre-digestion, a set of new peptide biomarkers was noticed to appear only in the samples containing a 11.6kDa peak. Further identification showed that 2177Da was a fragment of serum amyloid A (SAA, MW 11.6kDa). Two of the new peaks, 1550Da and 1611Da, were defined from the same protein by database searching. This result was further confirmed by partial purification of 11.6kDa protein and MS analysis. Conclusion SAA is a useful biomarker to monitor the progression of lung cancer and can directly identify some biomarkers on chip.
Association of A Common Haplotype of Hepatocyte Nuclear Factor 1α With Type 2 Diabetes in Chinese Population
2007, 20(1): 41-46.
Objective To analyze the association of variants of hepatocyte nuclear factor-1α (HNF-1α) gene with type 2 diabetes in Chinese population. Methods In 152 unrelated type 2 diabetes patients and 93 unrelated controls, eleven single nucleotide polymorphisms (SNPs) were identified and genotyped. Statistical analyses were performed to investigate whether these SNPs were associated with diabetes status in our samples. Results In the individual SNP study, no SNP differed significantly in frequency between type 2 diabetes patients and controls. In the haplotype analysis, two haplotype blocks were identified. In haplotype block 1, no evidence was found between common HNF-1α haplotypes and type 2 diabetes. However, in haplotype block 2, a common haplotype GCGC formed by four tagging SNPs (tSNPs) was found to be associated with decreased risk of type 2 diabetes (odds ratio [OR] 0.6011, 95% confidence interval [CI] 0.4138-0.8732,P=0.0073, empirical P=0.0511, permutation test). A similar trend was also observed in the diplotype analysis, indicating that the increasing copy number of the haplotype GCGC was associated with the decreased frequency of diabetes (P=0.0193). Conclusion The results of this study provide evidence that the haplotype of HNF-1α decreases the risk of type 2 diabetes in Chinese individuals.
Action of Schwann Cells Implanted in Cerebral Hemorrhage Lesion
2007, 20(1): 47-51.
Objective To investigate whether there is neogenesis of myelin sheath and neuron after transplantation of Schwann cells into cerebral hemorrhage lesion. Methods Schwann cells were expanded, labeled with BrdU in vitro and transplanted into rat cerebral hemorrhage with blood extracted from femoral artery and then injected into the basal nuclei. Double immunohistochemistry staining and electron microscopy were used to detect the expression of BrdU/MBP and BrdU/GAP-43 and remyelination. Results BrdU/MBP double positive cells could be seen at 1 week up to 16 weeks after transplantation of Schwann cells. Thin remyelination was observed under electron microscope. GAP-43 positive cells appeared after 12 weeks and were found more in Hippocamp. Conclusions Grafted Schwann cells participate in remyelination and promoter nerve restore in rat cerebral hemorrhage.
Is KPNB3 Locus Associated With Schizophrenia
2007, 20(1): 52-55.
Objective To reconfirm the association of KPNB3 with schizophrenia in Chinese population. Methods Two single nucleotide polymorphisms (SNPs), rs2588014 and rs626716 at the KPNB3 locus, were genotyped in 304 Chinese Han family trios consisting of fathers, mothers, and affected offsprings with schizophrenia. These 2 SNPs were detected by PCR-based restriction fragment length polymorphism (RFLP) analysis. The Hardy-Weinberg equilibrium for genotypic distributions was estimated by the goodness-of-fit test. The UNPHASED program was used to perform transmission disequilibrium test (TDT),haplotype analysis, and pair-wise measure of linkage disequilibrium (LD) between these 2 SNPs. Results The genotypic distributions of both rs2588014 and rs626716 were in the Hardy-Weinberg equilibrium (P>0.05). The TDT revealed allelic association with rs626716 (χ2 =9.31, P=0.0023) but not with rs2588014 (χ2 =3.44, P=0.064). The global P-value was 0.0099 for 100 permutations. The haplotype analysis also showed a disease association (χ2 =25.97, df=3, P=0.0000097). Conclusion The present study provides further evidence in support of the KPNB3 association with schizophrenia in Chinese population.
Effect of Pre-treatment of α-Ketoglutarate on Cyanide-induced Toxicity and Alterations in Various Physiological Variables in Rodents
2007, 20(1): 56-63.
Objective To investigate the effects of pre-treatment of α-ketoglutarate (αt-KG) on cyanide-induced lethality and changes in various physiological parameters in rodents. Methods The LD50 of potassium cyanide (KCN) given orally (po),intraperitoneally (ip), subcutaneously (sc) or intravenously (iv) was determined in male mice, in the presence or absence α-KG given po, ip or iv. α-KG was administered 10, 20 or 40 min prior to KCN at 0.50, 1.0 or 2.0 g/kg by po or ip route, and at 0.10,0.20 or 0.40 g/kg by iv route. Protection index (PI) was calculated as the ratio of LD50 of KCN in the presence of α-KG (protected animals) and LD50 of KCN in the absence of α-KG (unprotected animals). In a separate experiment, several physiological variables viz. mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), neuromuscular transmission (NMT) and rectal temperature (RT) were measured in anesthetized female rats pre-treated (-10 min) with po (2.0 g/kg) or iv (0.125 g/kg) α-KG and then administered sub-lethal (0.75 LD50) or lethal (2.0, 4.0 or 8.0 LD50) doses of KCN (po). Results PI of 4.52, 6.40 and 7.60 at -10 min, 3.20, 5.40 and 6.40 at -20 min, and 1.40, 3.20 and 5.40 at -40 min of po administration with α-KG was observed for 0.50, 1.0 and 2.0 g/kg doses, respectively, against KCN given by po route. When KCN was given ip, a PI of 3.38, 4.79 and 5.70 was observed for 0.50, 1.0 and 2.0 g/kg α-KG given ip (-10 min), respectively. A lower PI of 3.37,2.83 and 2.38 was observed when KCN given sc was challenged by 2.0 g/kg α-KG given ip at -10, -20 or -40 min, respectively.Similarly, a PI of 3.37, 2.83 and 2.0 was noted when KCN given sc was antagonized by 2.0 g/kg α-KG given po at -10, -20 or -40 min, respectively. No appreciable protection was observed when lower doses of α-KG (ip or po) challenged KCN given by sc route. Pre-treatment of iv or po administration of α-KG did not afford any protection against KCN given po or iv route. Oral treatment of 0.75 LD50 KCN caused significant decrease in MAP and HR after 15 min, RR after 30 min and NMT after 60 min.There was no effect on RT. No reduction in MAP, HR, RR and RT was observed when rats received 2.0 or 4.0 LD50 KCN after pre-treatment of α-KG (po; 2.0 g/kg). However, no protection was observed on NMT. Protective efficacy of α-KG was not observed on MAP, HR, RR, and NMT decreased by 8.0 LD50 KCN. Decrease in MAP and NMT caused by 2.0 LD50 KCN (po) was resolved by iv administration of α-KG. Conclusions Cyanide antagonism by α-KG is best exhibited when both α-KG and KCN are given by po route. The protective effect of α-KG on cyanide-induced changes in several physiological parameters also indicates a promising role of α-KG as an alternative cyanide antidote.
Specific Detection of Toxigenic Vibrio cholerae Based on in situ PCR in Combination With Flow Cytometry
2007, 20(1): 64-69.
Objective To develop an in situ PCR in combination with flow cytometry (ISPCR-FCM) for monitoring cholera toxin positive Vibrio cholerae. Methods In running this method, 4% paraformaldehyde was used to fix the Vibrio cholerae cells and 1 mg/mL lysozyme for 20 min to permeabilize the cells. Before the PCR thermal cycling, 2.5% glycerol was added into the PCR reaction mixture in order to protect the integrality of the cells. Results A length of 1037bp DNA sequence was amplified, which is specific for the cholera toxin gene (ctxAB gene). Cells subjected to ISPCR showed the presences of ctxAB gene both in epifiuorescence microscopy and in flow cytometric analysis. The specificity and sensitivity of the method were investigated. The sensitivity was relatively low (105 cells/mL), while the specificity was high. Conclusion We have successfully developed a new technique for detection of toxigenic Vibrio cholerae strains. Further study is needed to enhance its sensitivities. ISPCR-FCM shows a great promise in monitoring specific bacteria and their physiological states in environmental samples.
Effects of Wastewater Discharge on Heavy Metals Pollution in Fadama Soils in Kano City, Nigeria
2007, 20(1): 70-77.
Objective To present the results of a research project on 6 heavy metals (Cd, Cu, Zn, Pb, Hg, and Cr) at 30 Fadama fields scattered around Kano. Methods Following a reconnaissance conducted, 30 representative Fadama lands being irrigated with wastewater were selected from zones of the city under residential, industrial, commercial, and mixed but argely residential landuses. Five additional Fadama lands not being irrigated with wastewater were selected to serve as control. Using grid sampling procedure, soil samples were selected from 0-15 cm and 20-30 cm depths and analyzed for the above listed heavy metals using atomic absorption spectrophotometry. T-test was used to compare the mean alues of the metals for the Fadama lands under different landuse zones with those of the control. Results Analyses of the soil data collected showed that the metals were concentrated in higher amounts in the lower (20-30 cm) than the upper (0-15 cm) depths, which was an indication of downward movement of the metals in profile of the soils. In the wosoil epths, Zn was generally the most abundant,followed by Cr, then Pb, Cu, and Cd while Hg was the least. The Fadama soils in areas of mixed landuses with industrial as the dominant ones maintained the highest concentrations of the various metals. Conclusions These results indicate clearly that the Fadama soils are significantly polluted by industrial and household wastewater and that there is a particular threat from Cr and Pb pollution. There is also evidence that the metals are accumulating at lower layers of the soil profile, suggesting that not only plants and soil, but even water bodies could be under the threat of heavy metal pollution in the area.
A Novel Biosensor for the Rapid Determination of Biochemical Oxygen Demand
2007, 20(1): 78-83.
Objective To investigate the function of a novel biosensor used for the rapid determination of biochemical oxygen demand (BOD) which is developed by our research group based on suspended immobilized microbial cell system in a completely mixed determining chamber as a substitute of the traditional membrane system. Methods Activated sludge was immobilized by PVA gel and used as a bio-sensing element. The novel biosensor was used to measure the short time BOD value and the conventional cultivation method was used for BOD5 measurement. Results A linear relationship was observed for the difference between the current and the concentration of glucose-glutamic acid (GGA) solution below 200mg/L with a correlation coefficient of 0.995. The optimal response of the sensor was obtained at pH 7.0 and 30℃. The sensor response was within 15 min and was reproducible within ±5% of the mean in a series of eight samples containing 75 mg/L BOD using standard GGA solution. The novel sensor response was found to be fairly constant over a period of 0days, with ±5% fluctuations. Conclusion A relatively good agreement is found between BOD estimated by the novel BOD biosensor and that determined by the conventional 5-day BOD method. This novel BOD biosensor has good sensitivity, stability and reproducibility.
Consumption of Mercury-contaminated Rice Induces Oxidative Stress and Free Radical Aggravation in Rats
2007, 20(1): 84-89.
Objective To study the oxidative stress induced by consumption of mercury-contaminated rice in rats, and to assess the possible public health risk of mercury contamination in Wanshan mining area. Methods Sprague Dawley rats were fed the mercury-contaminated rice produced from Wanshan area for 90 days. The antioxidant status and the free radicals in rat serum were evaluated. Results High mercury accumulation in organs of rats fed the mercury-contaminated rice confirmed the server pollution of mercury in Wanshan mining area. The intensity of electron spin resonance (ESR) signal increased by 87.38% in rats fed the rice from Wanshan compared with that in the control rats fed the rice from Shanghai, suggesting that chronic dietary consumption of rice from mercury mining area could induce an aggravation of free radicals. Feeding the mercury-contaminated rice was associated with significant decreases in the antioxidant enzymatic activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and concentration of serum nitric oxide (NO), but it had no effect on serum nitric oxide synthase (NOS) activity. Feeding the mercury-contaminated rice raised the level of serum malonyldialdehyde (MDA), indicating the occurrence of oxidative stress. Conclusion The long-term dietary consumption of mercury-contaminated rice induces the aggravation of free radicals and exerts oxidative stress.
Biomedical and Environmental Sciences INFORMATION FOR AUTHORS
2007, 20(1): 封3-封4.